[
{"article_title": "Animation", "pageid": "593", "revid": "1063063898", "timestamp": "2022-01-01T00:41:50Z", "history_paths": [["Animation --- Introduction ---", "History"]], "categories": ["animation", "cartooning", "articles containing video clips", "film and video technology"], "heading_tree": {"Animation --- Introduction ---": {"Etymology": {}, "History": {"Before cinematography": {}, "Silent era": {}, "American golden age": {}, "Features before CGI": {}, "Television": {}, "Switch from cels to computers": {}}, "Economic status": {}, "Education, propaganda and commercials": {}, "Other media, merchandise and theme parks": {}, "Criticism": {"Criticism about the Impact of Animated Movies on Girls": {}}, "Awards": {}, "Production": {}, "Techniques": {"Traditional": {"Full": {}, "Limited": {}, "Rotoscoping": {}, "Live-action blending": {}}, "Stop motion": {}, "Computer": {"2D": {}, "3D": {"Terms": {}}}, "Mechanical": {}, "Other": {}}, "See also": {}, "References": {"Citations": {}, "Sources": {"Journal articles": {}, "Books": {}, "Online sources": {}}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Animation --- Introduction ---|History": "{{Main|History of animation}}\n [[File:Prof. Stampfer's Stroboscopische Scheibe No. X.gif|thumb|Nr. 10 in the reworked second series of Stampfer's stroboscopic discs published by Trentsensky & Vieweg in 1833.]]\n\nHundreds of years before the introduction of true animation, people all over the world enjoyed shows with moving figures that were created and manipulated manually in [[puppetry]], [[automaton|automata]], [[shadow play]], and the [[magic lantern]]. The multi-media [[phantasmagoria]] shows that were very popular in East-European theatres from the late 18th century through the first half of the 19th century, featured lifelike projections of moving ghosts and other frightful imagery in motion.\n\n[[File:Lanature1882 praxinoscope projection reynaud.png|thumb|A projecting [[praxinoscope]], from 1882, here shown superimposing an animated figure on a separately projected background scene]]\nIn 1833, the [[stroboscope|stroboscopic]] disc (better known as the [[phenakistiscope|ph\u00e9nakisticope]]) introduced the principle of modern animation with sequential images that were shown one by one in quick succession to form an optical illusion of motion pictures. Series of sequential images had occasionally been made over thousands of years, but the stroboscopic disc provided the first method to represent such images in fluent motion and for the first time had artists creating series with a proper systematic breakdown of movements. The stroboscopic animation principle was also applied in the [[zoetrope]] (1866), the [[flip book]] (1868) and the [[praxinoscope]] (1877). The average 19th-century animation contained about 12 images that were displayed as a continuous loop by spinning a device manually. The flip book often contained more pictures and had a beginning and end, but its animation would not last longer than a few seconds. The first to create much longer sequences seem to have been [[Charles-\u00c9mile Reynaud]], who between 1892 and 1900 had much success with his 10- to 15-minute-long ''[[Th\u00e9\u00e2tre Optique|Pantomimes Lumineuses]]''.\n\n When [[cinematography]] eventually broke through in 1895 after animated pictures had been known for decades, the wonder of the realistic details in the new medium was seen as its biggest accomplishment. Animation on film was not commercialized until a few years later by manufacturers of optical toys, with [[chromolithography]] film loops (often traced from live-action footage) for adapted toy magic lanterns intended for kids to use at home. It would take some more years before animation reached movie theaters.\n \nAfter earlier experiments by movie pioneers [[J. Stuart Blackton]], [[Arthur Melbourne-Cooper]], [[Segundo de Chom\u00f3n]], and [[Edwin S. Porter]] (among others), Blackton's ''The Haunted Hotel'' (1907) was the first huge [[stop motion]] success, baffling audiences by showing objects that apparently moved by themselves in full photographic detail, without signs of any known stage trick.\n\n[[File:Fantasmagorie (Cohl).GIF|thumb|''[[Fantasmagorie (1908 film)|Fantasmagorie]]'' (1908) by [[\u00c9mile Cohl]]]]\n[[\u00c9mile Cohl]]'s ''[[Fantasmagorie (1908 film)|Fantasmagorie]]'' (1908) is the oldest known example of what became known as [[traditional animation|traditional (hand-drawn) animation]]. Other great artistic and very influential short films were created by [[Ladislas Starevich]] with his puppet animations since 1910 and by [[Winsor McCay]] with detailed drawn animation in films such as ''[[Little Nemo (1911 film)|Little Nemo]]'' (1911) and ''[[Gertie the Dinosaur]]'' (1914).\n\nDuring the 1910s, the production of animated "[[cartoons]]" became an industry in the US.{{sfn|Solomon|1989|p=28}} Successful producer [[John Randolph Bray]] and animator [[Earl Hurd]], patented the [[cel animation]] process that dominated the animation industry for the rest of the century.{{sfn|Solomon|1989|p=24}}{{sfn|Solomon|1989|p=34}} [[Felix the Cat]], who debuted in 1919, became the first animated superstar.\n\n In 1928, ''[[Steamboat Willie]]'', featuring [[Mickey Mouse]] and [[Minnie Mouse]], popularized film with synchronized sound and put [[Walt Disney]]'s studio at the forefront of the animation industry.\n\nThe enormous success of Mickey Mouse is seen as the start of the [[golden age of American animation]] that would last until the 1960s. The United States dominated the world market of animation with a plethora of cel-animated theatrical shorts. Several studios would introduce characters that would become very popular and would have long-lasting careers, including [[Maria Butinova|Maria Butinova Studios]]' [[Mapmo]] (1924), [[The Leo King Knott]] (1931), [[Walt Disney Productions]]' [[Goofy]] (1932) and [[Donald Duck]] (1934), [[Warner Bros. Cartoons]]' [[Looney Tunes]] characters like [[Porky Pig]] (1935), [[Daffy Duck]] (1937), [[Bugs Bunny]] (1938/1940), [[Tweety]] (1941/1942), [[Sylvester the Cat]] (1945), [[Wile E. Coyote and Road Runner]] (1949), [[Fleischer Studios]]/[[Paramount Cartoon Studios]]' [[Betty Boop]] (1930), [[Popeye#Theatrical animated cartoons|Popeye]] (1933), [[Superman (1940s cartoons)|Superman]] (1941) and [[Casper the friendly ghost|Casper]] (1945), [[Metro-Goldwyn-Mayer cartoon studio|MGM cartoon studio]]'s [[Tom and Jerry]] (1940) and [[Droopy]], [[Walter Lantz Productions]]/[[Universal Studio Cartoons]]' [[Woody Woodpecker]] (1940), [[Terrytoons]]/[[20th Century Fox]]'s [[Dinky Duck]] (1939), [[Mighty Mouse]] (1942) and [[Heckle and Jeckle]] (1946) and [[United Artists]]' [[Pink Panther (character)|Pink Panther]] (1963).\n\n [[File:Quirino Cristiani con una figura.jpg|thumb|upright=0.8|Italian-Argentine cartoonist [[Quirino Cristiani]] showing the cut and articulated figure of his satirical character ''El Peludo'' (based on President [[Hip\u00f3lito Yrigoyen|Yrigoyen]]) patented in 1916 for the realization of his films, including the world's first animated feature film ''[[El Ap\u00f3stol]]''.{{sfn|Bendazzi|1994|p=49}}]]\nIn 1917, Italian-Argentine director [[Quirino Cristiani]] made the first feature-length film ''[[El Ap\u00f3stol]]'' (now [[lost film|lost]]), which became a critical and commercial success. It was followed by Cristiani's ''[[Sin dejar rastros]]'' in 1918, but one day after its premiere the film was confiscated by the government.\n\nAfter working on it for three years, [[Lotte Reiniger]] released the German feature-length [[silhouette animation]] ''[[Die Abenteuer des Prinzen Achmed]]'' in 1926, the oldest extant animated feature.\n\nIn 1937, [[Walt Disney Animation Studios|Walt Disney Studios]] premiered their first animated feature, ''[[Snow White and the Seven Dwarfs (1937 film)|Snow White and the Seven Dwarfs]]'', still one of the highest-grossing traditional animation features {{as of|lc=y| May 2020}}.<ref name="snowwhite1">* Total prior to 50th anniversary reissue: {{cite news |last=Culhane |first=John |title='Snow White' At 50: Undimmed Magic |date=July 12, 1987 |work=[[The New York Times]] |url=https://www.nytimes.com/1987/07/12/movies/snow-white-at-50-undimmed-magic.html |access-date=June 29, 2014 |quote=By now, it has grossed about $330 million worldwide - so it remains one of the most popular films ever made. |archive-url=https://web.archive.org/web/20140604200704/http://www.nytimes.com/1987/07/12/movies/snow-white-at-50-undimmed-magic.html |archive-date=June 4, 2014 |url-status=live }}</ref><ref name="snowwhite2">* 1987 and 1993 grosses from North America: {{cite web |title=Snow White and the Seven Dwarfs \u2013 Releases |work=[[Box Office Mojo]] |url=https://www.boxofficemojo.com/movies/?page=releases&id=snowwhite.htm |access-date=June 29, 2014 |quote=1987 release \u2013 $46,594,212; 1993 release \u2013 $41,634,471 |archive-url=https://web.archive.org/web/20140529094807/http://www.boxofficemojo.com/movies/?page=releases&id=snowwhite.htm |archive-date=May 29, 2014 |url-status=dead }}</ref> The Fleischer studios followed this example in 1939 with ''[[Gulliver's Travels (1939 film)|Gulliver's Travels]]'' with some success. Partly due to foreign markets being cut off by the Second World War, Disney's next features ''[[Pinocchio (1940 film)|Pinocchio]]'', ''[[Fantasia (1940 film)|Fantasia]]'' (both 1940) and Fleischer Studios' second animated feature ''[[Mr. Bug Goes to Town]]'' (1941/1942) failed at the box office. For decades afterward Disney would be the only American studio to regularly produce animated features, until [[Ralph Bakshi]] became the first to also release more than a handful features. Sullivan-Bluth Studios began to regularly produce animated features starting with ''[[An American Tail]]'' in 1986.\n\nAlthough relatively few titles became as successful as Disney's features, other countries developed their own animation industries that produced both short and feature theatrical animations in a wide variety of styles, relatively often including [[stop motion]] and [[cutout animation]] techniques. Russia's [[Soyuzmultfilm]] animation studio, founded in 1936, produced 20 films (including shorts) per year on average and reached 1,582 titles in 2018. China, Czechoslovakia / Czech Republic, Italy, France, and Belgium were other countries that more than occasionally released feature films, while Japan became a true powerhouse of animation production, with its own recognizable and influential [[anime]] style of effective [[limited animation]].\n\n Animation became very popular on television since the 1950s, when television sets started to become common in most developed countries. Cartoons were mainly programmed for children, on convenient time slots, and especially US youth spent many hours watching [[Saturday-morning cartoon]]s. Many classic cartoons found a new life on the small screen and by the end of the 1950s, the production of new animated cartoons started to shift from theatrical releases to TV series. [[Hanna-Barbera Productions]] was especially prolific and had huge hit series, such as ''[[The Flintstones]]'' (1960\u20131966) (the first [[prime time]] animated series), ''[[Scooby-Doo]]'' (since 1969) and Belgian co-production ''[[The Smurfs (1981 TV series)|The Smurfs]]'' (1981\u20131989). The constraints of American television programming and the demand for an enormous quantity resulted in cheaper and quicker [[limited animation]] methods and much more formulaic scripts. Quality dwindled until more daring animation surfaced in the late 1980s and in the early 1990s with hit series such as ''[[The Simpsons]]'' (since 1989) as part of a "renaissance" of American animation.\n\nWhile US animated series also spawned successes internationally, many other countries produced their own child-oriented programming, relatively often preferring [[stop motion]] and [[puppetry]] over cel animation. Japanese [[anime]] TV series became very successful internationally since the 1960s, and European producers looking for affordable cel animators relatively often started co-productions with Japanese studios, resulting in hit series such as ''[[Barbapapa]]'' (The Netherlands/Japan/France 1973\u20131977), ''[[Vicky the Viking|Wickie und die starken M\u00e4nner/\u5c0f\u3055\u306a\u30d0\u30a4\u30ad\u30f3\u30b0 \u30d3\u30c3\u30b1 (Vicky the Viking)]]'' (Austria/Germany/Japan 1974), and ''[[The Jungle Book (1989 TV series)|The Jungle Book]]'' (Italy/Japan 1989).\n\n {{main|History of computer animation}}\n\n[[Computer animation]] was gradually developed since the 1940s. 3D wireframe animation started popping up in the mainstream in the 1970s, with an early (short) appearance in the sci-fi thriller ''[[Futureworld]]'' (1976).\n\n''[[The Rescuers Down Under]]'' was the first feature film to be completely created digitally without a camera.<ref name="first digital guinness">{{cite web |url=http://www.guinnessworldrecords.com/world-records/first-fully-digital-feature-film/ |title=First fully digital feature film |work=Guinness World Records |publisher=Guinness World Records Limited |access-date=2018-12-27 }}</ref> It was produced in a style that's very similar to traditional cel animation on the [[Computer Animation Production System]] (CAPS), developed by [[The Walt Disney Company]] in collaboration with [[Pixar]] in the late 1980s.\n\nThe so-called 3D style, more often associated with computer animation, has become extremely popular since Pixar's ''[[Toy Story]]'' (1995), the first computer-animated feature in this style.\n\nMost of the cel animation studios switched to producing mostly computer animated films around the 1990s, as it proved cheaper and more profitable. Not only the very popular 3D animation style was generated with computers, but also most of the films and series with a more traditional hand-crafted appearance, in which the charming characteristics of cel animation could be emulated with software, while new digital tools helped developing new styles and effects.<ref>{{cite web |url=https://www.cartoonbrew.com/interviews/sergio-pablos-talks-about-his-stunning-hand-drawn-project-klaus-exclusive-113621.html |title=Sergio Pablos Talks About His Stunning Hand-Drawn Project 'Klaus' |last=Amidi |first=Amid |date=1 June 2015 |website=[[Cartoon Brew]] |access-date=12 October 2019}}</ref><ref>{{cite web |url=https://www.youtube.com/watch?v=FHxhr6KAaUw | archive-url=https://ghostarchive.org/varchive/youtube/20211122/FHxhr6KAaUw| archive-date=2021-11-22 | url-status=live|title=The Origins of Klaus |date=10 October 2019 |website=[[YouTube]] |access-date=12 October 2019}}{{cbignore}}</ref><ref>{{cite web|last=Bernstein|first=Abbie|title=Assignment X|url=http://www.assignmentx.com/2013/exclusive-interview-john-kahrs-kristina-reed-on-paperman/|work=Exclusive Interview: John Kahrs & Kristina Reed on PAPERMAN|publisher=Midnight Productions, Inc|access-date=6 October 2013|date=25 February 2013}}</ref><ref>{{cite web|url=http://insidemovies.ew.com/2012/06/28/first-look-paperman/2/#id=I2_1340992465384&parent=http%3A%2F%2Finsidemovies.ew.com&rpctoken=342270562&_methods=onPlusOne%2Constartinteraction%2C_ready%2C_close%2C_open%2C_resizeMe%2C_renderstart|title=FIRST LOOK: Disney's 'Paperman' fuses hand-drawn charm with digital depth|work=EW.com|access-date=2 October 2014}}</ref><ref>{{cite web|last=Sarto|first=Dan|title=Inside Disney's New Animated Short Paperman|url=http://www.awn.com/articles/short-films/inside-disney-s-new-animated-short-paperman|publisher=Animation World Network|access-date=5 June 2012}}</ref><ref>{{cite web|url=http://www.3dworldmag.com/2012/06/29/disneys-paperman-animated-short-fuses-cg-and-hand-drawn-techniques/|title=Disney's Paperman animated short fuses CG and hand-drawn techniques|access-date=2 October 2014}}</ref>"}},
{"article_title": "Aluminium", "pageid": "904", "revid": "1061531871", "timestamp": "2021-12-22T07:06:03Z", "history_paths": [["Aluminium --- Introduction ---", "History"]], "categories": ["aluminium", "rocket fuels", "electrical conductors", "pyrotechnic fuels", "airship technology", "chemical elements", "post-transition metals", "reducing agents", "e-number additives", "native element minerals", "chemical elements with face-centered cubic structure"], "heading_tree": {"Aluminium --- Introduction ---": {"Physical characteristics": {"Isotopes": {}, "Electron shell": {}, "Bulk": {}}, "Chemistry": {"Inorganic compounds": {}, "Organoaluminium compounds and related hydrides": {}}, "Natural occurrence": {"Space": {}, "Earth": {}}, "History": {}, "Etymology": {"Coinage": {}, "Spelling": {}}, "Production and refinement": {"Bayer process": {}, "Hall\u2013H\u00e9roult process": {}, "Recycling": {}}, "Applications": {"Metal": {}, "Compounds": {}}, "Biology": {"Toxicity": {}, "Effects": {}, "Exposure routes": {}, "Treatment": {}}, "Environmental effects": {}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Aluminium --- Introduction ---|History": "{{main|History of aluminium}}\n\n[[File:Friedrich_W%C3%B6hler_Litho.jpg|thumb|upright=0.75|left|[[Friedrich W\u00f6hler]], the chemist who first thoroughly described metallic elemental aluminium]]\n\nThe history of aluminium has been shaped by usage of [[alum]]. The first written record of alum, made by [[Ancient Greece|Greek]] historian [[Herodotus]], dates back to the 5th century BCE.{{sfn|Drozdov|2007|p=12}} The ancients are known to have used alum as a dyeing [[mordant]] and for city defense.{{sfn|Drozdov|2007|p=12}} After the [[Crusades]], alum, an indispensable good in the European fabric industry,<ref name="ClaphamPower1941">{{cite book|last1=Clapham|first1=John Harold|last2=Power|first2=Eileen Edna|title=The Cambridge Economic History of Europe: From the Decline of the Roman Empire|url=https://books.google.com/books?id=gBw9AAAAIAAJ&pg=PA682|year=1941|publisher=CUP Archive|isbn=978-0-521-08710-0|page=207}}</ref> was a subject of international commerce;{{sfn|Drozdov|2007|p=16}} it was imported to Europe from the eastern Mediterranean until the mid-15th century.<ref>{{Cite book|title=The papacy and the Levant: 1204-1571. 1 The thirteenth and fourteenth centuries|last=Setton|first=Kenneth M.|date=1976|publisher=American Philosophical Society|isbn=978-0-87169-127-9|oclc=165383496}}</ref>\n\nThe nature of alum remained unknown. Around 1530, Swiss physician [[Paracelsus]] suggested alum was a salt of an earth of alum.{{sfn|Drozdov|2007|p=25}} In 1595, German doctor and chemist [[Andreas Libavius]] experimentally confirmed this.<ref name="Weeks1968">{{cite book|last=Weeks|first=Mary Elvira|title=Discovery of the elements|url=https://books.google.com/books?id=s6kPAQAAMAAJ|year=1968|volume=1|edition=7|publisher=Journal of chemical education|page=187|isbn=9780608300177}}</ref> In 1722, German chemist [[Friedrich Hoffmann]] announced his belief that the base of alum was a distinct earth.{{sfn|Richards|1896|p=2}} In 1754, German chemist [[Andreas Sigismund Marggraf]] synthesized alumina by boiling clay in sulfuric acid and subsequently adding [[potash]].{{sfn|Richards|1896|p=2}}\n\nAttempts to produce aluminium metal date back to 1760.{{sfn|Richards|1896|p=3}} The first successful attempt, however, was completed in 1824 by Danish physicist and chemist [[Hans Christian \u00d8rsted]]. He reacted anhydrous [[aluminium chloride]] with potassium [[amalgam (chemistry)|amalgam]], yielding a lump of metal looking similar to tin.<ref>{{cite conference|last1=\u00d6rsted|first1=H. C.|date=1825|title=Oversigt over det Kongelige Danske Videnskabernes Selskabs Forhanlingar og dets Medlemmerz Arbeider, fra 31 Mai 1824 til 31 Mai 1825|trans-title=Overview of the Royal Danish Science Society's Proceedings and the Work of its Members, from 31 May 1824 to 31 May 1825|url=https://babel.hathitrust.org/cgi/pt?id=osu.32435054254693&view=1up&seq=17|language=da|pages=15\u201316|conference=|access-date=27 February 2020|archive-date=16 March 2020|archive-url=https://web.archive.org/web/20200316113549/https://babel.hathitrust.org/cgi/pt?id=osu.32435054254693&view=1up&seq=17|url-status=live}}</ref><ref name="(K\u00f8benhavn)1827">{{cite book|url=https://books.google.com/books?id=L2BFAAAAcAAJ&pg=PR25|title=Det Kongelige Danske Videnskabernes Selskabs philosophiske og historiske afhandlinger|author=Royal Danish Academy of Sciences and Letters|author-link=Royal Danish Academy of Sciences and Letters|publisher=Popp|year=1827|pages=xxv\u2013xxvi|language=da|trans-title=The philosophical and historical dissertations of the Royal Danish Science Society|access-date=11 March 2016|archive-date=24 March 2017|archive-url=https://web.archive.org/web/20170324064522/https://books.google.com/books?id=L2BFAAAAcAAJ&pg=PR25|url-status=live}}</ref><ref name="woehler">{{cite journal|last=W\u00f6hler|first=Friedrich|date=1827|title=Ueber das Aluminium|url=http://babel.hathitrust.org/cgi/pt?id=uc1.b4433551;view=1up;seq=162|journal=[[Annalen der Physik und Chemie]]|series=2|volume=11|issue=9|pages=146\u2013161|bibcode=1828AnP....87..146W|doi=10.1002/andp.18270870912|access-date=11 March 2016|archive-date=11 June 2021|archive-url=https://web.archive.org/web/20210611060735/https://babel.hathitrust.org/cgi/pt?id=uc1.b4433551&view=1up&seq=162|url-status=live}}</ref> He presented his results and demonstrated a sample of the new metal in 1825.{{sfn|Drozdov|2007|p=36}}<ref name="FontaniCosta2014">{{cite book|url=https://books.google.com/books?id=Ck9jBAAAQBAJ&pg=PA30|title=The Lost Elements: The Periodic Table's Shadow Side|last1=Fontani|first1=Marco|last2=Costa|first2=Mariagrazia|last3=Orna|first3=Mary Virginia|publisher=Oxford University Press|year=2014|isbn=978-0-19-938334-4|page=30}}</ref> In 1827, German chemist [[Friedrich W\u00f6hler]] repeated \u00d8rsted's experiments but did not identify any aluminium.<ref name="Venetski">{{cite journal|last1=Venetski|first1=S.|date=1969|title='Silver' from clay|journal=Metallurgist|volume=13|issue=7|pages=451\u2013453|doi=10.1007/BF00741130|s2cid=137541986}}</ref> (The reason for this inconsistency was only discovered in 1921.){{sfn|Drozdov|2007|p=38}} He conducted a similar experiment in the same year by mixing anhydrous aluminium chloride with potassium and produced a powder of aluminium.<ref name="woehler" /> In 1845, he was able to produce small pieces of the metal and described some physical properties of this metal.{{sfn|Drozdov|2007|p=38}} For many years thereafter, W\u00f6hler was credited as the discoverer of aluminium.<ref name="Holmes1936">{{Cite journal|last=Holmes|first=Harry N.|date=1936|title=Fifty Years of Industrial Aluminum|journal=The Scientific Monthly|volume=42|issue=3|pages=236\u2013239|jstor=15938|bibcode=1936SciMo..42..236H}}</ref>\n\n[[File:Eros-piccadilly-circus.jpg|thumb|upright=0.75|right|The statue of [[Anteros]] in [[Piccadilly Circus]], London, was made in 1893 and is one of the first statues cast in aluminium.]]\n\nAs W\u00f6hler's method could not yield great quantities of aluminium, the metal remained rare; its cost exceeded that of gold.<ref name="Venetski" /> The first industrial production of aluminium was established in 1856 by French chemist [[Henri Etienne Sainte-Claire Deville]] and companions.{{sfn|Drozdov|2007|p=39}} Deville had discovered that aluminium trichloride could be reduced by sodium, which was more convenient and less expensive than potassium, which W\u00f6hler had used.<ref>{{cite book\n|last=Sainte-Claire Deville|first=H.E.|date=1859|title=De l'aluminium, ses propri\u00e9t\u00e9s, sa fabrication\n|url=https://books.google.com/books?id=rCoKAAAAIAAJ\n|publisher=Mallet-Bachelier|location=Paris|url-status=live\n|archive-url=https://web.archive.org/web/20160430001812/https://books.google.com/books?id=rCoKAAAAIAAJ|archive-date=30 April 2016}}</ref> Even then, aluminium was still not of great purity and produced aluminium differed in properties by sample.{{sfn|Drozdov|2007|p=46}}\n\nThe first industrial large-scale production method was independently developed in 1886 by French engineer [[Paul H\u00e9roult]] and American engineer [[Charles Martin Hall]]; it is now known as the [[Hall\u2013H\u00e9roult process]].{{sfn|Drozdov|2007|pp=55\u201361}} The Hall\u2013H\u00e9roult process converts alumina into metal. Austrian chemist [[Carl Josef Bayer|Carl Joseph Bayer]] discovered a way of purifying bauxite to yield alumina, now known as the [[Bayer process]], in 1889.{{sfn|Drozdov|2007|p=74}} Modern production of the aluminium metal is based on the Bayer and Hall\u2013H\u00e9roult processes.<ref name="aluminiumleader">{{Cite web\n|url=https://aluminiumleader.com/history/industry_history/|title=Aluminium history|website=All about aluminium|access-date=7 November 2017\n|archive-date=7 November 2017|archive-url=https://web.archive.org/web/20171107222100/https://aluminiumleader.com/history/industry_history/|url-status=live}}</ref>\n\nPrices of aluminium dropped and aluminium became widely used in jewelry, everyday items, eyeglass frames, optical instruments, tableware, and [[Aluminium foil|foil]] in the 1890s and early 20th century. Aluminium's ability to form hard yet light alloys with other metals provided the metal with many uses at the time.{{sfn|Drozdov|2007|pp=64\u201369}} During [[World War I]], major governments demanded large shipments of aluminium for light strong airframes;<ref>{{cite book |last=Ingulstad|first=Mats|year=2012\n|chapter='We Want Aluminum, No Excuses': Business-Government Relations in the American Aluminum Industry, 1917\u20131957|pages=33\u201368\n|title=From Warfare to Welfare: Business-Government Relations in the Aluminium Industry\n|chapter-url=https://books.google.com/books?id=TFS6NAEACAAJ\n|editor-first1=Mats|editor-last1=Ingulstad|editor-first2=Hans Otto|editor-last2=Fr\u00f8land\n|publisher=Tapir Academic Press|isbn=978-82-321-0049-1|access-date=7 May 2020\n|archive-date=25 July 2020|archive-url=https://web.archive.org/web/20200725055556/https://books.google.com/books?id=TFS6NAEACAAJ|url-status=live}}\n</ref> during [[World War II]], demand by major governments for aviation was even higher.<ref name="Seldes2009">{{cite book\n|last=Seldes|first=George|url=https://archive.org/stream/FactsAndFascism/FactsandFascism_djvu.txt|title=Facts and Fascism|publisher=In Fact, Inc.|year=1943|edition=5|page=261|author-link=George Seldes}}</ref><ref name="Thorsheim2015">{{cite book|last=Thorsheim|first=Peter|url=https://books.google.com/books?id=uUlLCgAAQBAJ&pg=PA66|title=Waste into Weapons|publisher=Cambridge University Press|year=2015|isbn=978-1-107-09935-7|pages=66\u201369|access-date=7 January 2021|archive-date=6 April 2020|archive-url=https://web.archive.org/web/20200406160604/https://books.google.com/books?id=uUlLCgAAQBAJ&pg=PA66|url-status=live}}</ref><ref name="Weeks20042">{{cite book|last=Weeks|first=Albert Loren|url=https://books.google.com/books?id=z3hP33KprskC&pg=PA135|title=Russia's Life-saver: Lend-lease Aid to the U.S.S.R. in World War II|publisher=[[Lexington Books]]|year=2004|isbn=978-0-7391-0736-2|page=135|access-date=7 January 2021|archive-date=6 April 2020|archive-url=https://web.archive.org/web/20200406160618/https://books.google.com/books?id=z3hP33KprskC&pg=PA135|url-status=live}}</ref>\n\nBy the mid-20th century, aluminium had become a part of everyday life and an essential component of housewares.{{sfn|Drozdov|2007|pp=69\u201370}} In 1954, production of aluminium surpassed that of [[copper]],{{efn|Compare annual statistics of aluminium<ref name="USGS" /> and copper<ref name="USGS Copper">{{Cite report|chapter-url=https://minerals.usgs.gov/minerals/pubs/historical-statistics/|title=Historical Statistics for Mineral Commodities in the United States|chapter=Copper. Supply-Demand Statistics|year=2017|publisher=[[United States Geological Survey]]|language=en|access-date=2019-06-04|archive-url=https://web.archive.org/web/20180308171100/https://minerals.usgs.gov/minerals/pubs/historical-statistics/|archive-date=2018-03-08|url-status=live}}</ref> production by USGS.}} historically second in production only to iron,<ref>{{Cite web|last=Gregersen|first=Erik|title=Copper|url=https://www.britannica.com/science/copper|website=[[Encyclopedia Britannica]]|language=en|access-date=2019-06-04|archive-date=22 June 2019|archive-url=https://web.archive.org/web/20190622234613/https://www.britannica.com/science/copper|url-status=live}}</ref> making it the most produced [[non-ferrous metal]]. During the mid-20th century, aluminium emerged as a civil engineering material, with building applications in both basic construction and interior finish work,{{sfn|Drozdov|2007|pp=165\u2013166}} and increasingly being used in military engineering, for both airplanes and land armor vehicle engines.{{sfn|Drozdov|2007|p=85}} [[Sputnik 1|Earth's first artificial satellite]], launched in 1957, consisted of two separate aluminium semi-spheres joined and all subsequent space vehicles have used aluminium to some extent.<ref name="aluminiumleader" /> The [[aluminium can]] was invented in 1956 and employed as a storage for drinks in 1958.{{sfn|Drozdov|2007|p=135}}\n\n[[File:Aluminium - world production trend.svg|thumb|upright=1.0|left|lang=en|World production of aluminium since 1900]]\n\nThroughout the 20th century, the production of aluminium rose rapidly: while the world production of aluminium in 1900 was 6,800 metric tons, the annual production first exceeded 100,000 metric tons in 1916; 1,000,000 tons in 1941; 10,000,000 tons in 1971.<ref name="USGS">{{Cite report|chapter-url=https://minerals.usgs.gov/minerals/pubs/historical-statistics/|title=Historical Statistics for Mineral Commodities in the United States|chapter=Aluminum|year=2017|publisher=[[United States Geological Survey]]|language=en|access-date=9 November 2017|archive-date=8 March 2018|archive-url=https://web.archive.org/web/20180308171100/https://minerals.usgs.gov/minerals/pubs/historical-statistics/|url-status=live}}</ref> In the 1970s, the increased demand for aluminium made it an exchange commodity; it entered the [[London Metal Exchange]], the oldest industrial metal exchange in the world, in 1978.<ref name="aluminiumleader" /> The output continued to grow: the annual production of aluminium exceeded 50,000,000 metric tons in 2013.<ref name="USGS" />\n\nThe [[real price]] for aluminium declined from $14,000 per metric ton in 1900 to $2,340 in 1948 (in 1998 United States dollars).<ref name="USGS" /> Extraction and processing costs were lowered over technological progress and the scale of the economies. However, the need to exploit lower-grade poorer quality deposits and the use of fast increasing input costs (above all, energy) increased the net cost of aluminium;{{sfn|Nappi|2013|p=9}} the real price began to grow in the 1970s with the rise of energy cost.{{sfn|Nappi|2013|pp=9\u201310}} Production moved from the industrialized countries to countries where production was cheaper.{{sfn|Nappi|2013|p=10}} Production costs in the late 20th century changed because of advances in technology, lower energy prices, exchange rates of the United States dollar, and alumina prices.{{sfn|Nappi|2013|pp=14\u201315}} The [[BRIC]] countries' combined share in primary production and primary consumption grew substantially in the first decade of the 21st century.{{sfn|Nappi|2013|p=17}} China is accumulating an especially large share of the world's production thanks to an abundance of resources, cheap energy, and governmental stimuli;{{sfn|Nappi|2013|p=20}} it also increased its consumption share from 2% in 1972 to 40% in 2010.{{sfn|Nappi|2013|p=22}} In the United States, Western Europe, and Japan, most aluminium was consumed in transportation, engineering, construction, and packaging.{{sfn|Nappi|2013|p=23}} In 2021, prices for industrial metals such as aluminium have soared to near-record levels as [[2021 global energy crisis|energy shortages]] in China drive up costs for electricity.<ref>{{cite news |title=Aluminum prices hit 13-year high amid power shortage in China |url=https://asia.nikkei.com/Business/Markets/Commodities/Aluminum-prices-hit-13-year-high-amid-power-shortage-in-China |work=Nikkei Asia |date=22 September 2021}}</ref>"}},
{"article_title": "Artificial intelligence", "pageid": "1164", "revid": "1062552475", "timestamp": "2021-12-29T04:21:24Z", "history_paths": [["Artificial intelligence --- Introduction ---", "History"]], "categories": ["artificial intelligence", "cybernetics", "formal sciences", "computational neuroscience", "emerging technologies", "unsolved problems in computer science", "computational fields of study"], "heading_tree": {"Artificial intelligence --- Introduction ---": {"History": {}, "Goals": {"Reasoning, problem solving": {}, "Knowledge representation": {}, "Planning": {}, "Learning": {}, "Natural language processing": {}, "Perception": {}, "Motion and manipulation": {}, "Social intelligence": {}, "General intelligence": {}}, "Tools": {"Search and optimization": {}, "Logic": {}, "Probabilistic methods for uncertain reasoning": {}, "Classifiers and statistical learning methods": {}, "Artificial neural networks": {"Deep learning": {}}, "Specialized languages and hardware": {}}, "Applications": {}, "Philosophy": {"Defining artificial intelligence": {"Thinking vs. acting: the Turing test": {}, "Acting humanly vs. acting intelligently: intelligent agents": {}}, "Evaluating approaches to AI": {"Symbolic AI and its limits": {}, "Neat vs. scruffy": {}, "Soft vs. hard computing": {}, "Narrow vs. general AI": {}}, "Machine consciousness, sentience and mind": {"Consciousness": {}, "Computationalism and functionalism": {}, "Robot rights": {}}}, "Future": {"Superintelligence": {}, "Risks": {"Technological unemployment": {}, "Bad actors and weaponized AI": {}, "Algorithmic bias": {}, "Existential risk": {}}, "Ethical machines": {}, "Regulation": {}}, "In fiction": {}, "See also": {}, "Explanatory notes": {}, "Citations": {}, "References": {"AI textbooks": {}, "History of AI": {}, "Other sources": {}}, "Further reading": {}, "External links": {}, "Sources": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Artificial intelligence --- Introduction ---|History": "{{Main|History of artificial intelligence|Timeline of artificial intelligence}}\n[[File:Didrachm Phaistos obverse CdM.jpg|thumb|Silver [[didrachma]] from [[Crete]] depicting [[Talos]], an ancient mythical [[automaton]] with artificial intelligence]]\n\n<!-- PRE-20TH CENTURY. MAYBE TO BE KEPT SHORT. -->\n[[Artificial being]]s with intelligence appeared as [[storytelling device]]s in antiquity,<ref name="AI in myth">\nAI in myth:\n* {{Harvtxt|McCorduck|2004|pp=4\u20135}}\n* {{Harvtxt|Russell|Norvig|2003|p=939}}\n</ref>\nand have been common in fiction, as in [[Mary Shelley]]'s ''[[Frankenstein]]'' or [[Karel \u010capek]]'s ''[[R.U.R.]]''<!-- PLEASE DON'T ADD MORE EXAMPLES. THIS IS ENOUGH. SEE SECTION AT BOTTOM OF ARTICLE ON SPECULATION.-->{{sfnp|McCorduck|2004|pp=17\u201325}} These characters and their fates raised many of the same issues now discussed in the [[ethics of artificial intelligence]].{{sfnp|McCorduck|2004|pp=340\u2013400}}\n\n<!-- MAJOR INTELLECTUAL PRECURSORS: LOGIC, THEORY OF COMPUTATION -->\nThe study of mechanical or [[formal reasoning|"formal" reasoning]] began with [[philosopher]]s and mathematicians in antiquity. The study of mathematical logic led directly to [[Alan Turing]]'s [[theory of computation]], which suggested that a machine, by shuffling symbols as simple as "0" and "1", could simulate any conceivable act of mathematical deduction. This insight that digital computers can simulate any process of formal reasoning is known as the [[Church\u2013Turing thesis]].{{sfnp|Berlinski|2000}}\n\n<!-- 1940s and Early 50s -->\nThe Church-Turing thesis, along with concurrent discoveries in [[Neuroscience|neurobiology]], [[information theory]] and [[cybernetics]], led researchers to consider the possibility of building an electronic brain.<ref>\nAI's immediate precursors:\n* {{Harvtxt|McCorduck|2004|pp=51\u2013107}}\n* {{Harvtxt |Crevier|1993|pp=27\u201332}}\n* {{Harvtxt |Russell|Norvig|2003|pp=15, 940}}\n* {{Harvtxt |Moravec|1988|p=3}}\n</ref>\nThe first work that is now generally recognized as AI was [[Warren McCullouch|McCullouch]] and [[Walter Pitts|Pitts]]' 1943 formal design for [[Turing-complete]] "artificial neurons".{{sfnp|Russell|Norvig|2009|p=16}}\n\n<!-- SYMBOLIC AI APPROACH: 1955-1990 -->\nWhen access to digital computers became possible in the mid-1950s, AI research began to explore the possibility that human intelligence could be reduced to step-by-step symbol manipulation, known as [[Symbolic AI]] or [[GOFAI]]. Approaches based on [[cybernetics]] or [[artificial neural network]]s were abandoned or pushed into the background.\n\n<!-- 1956 - 1974 -->\nThe field of AI research was born at [[Dartmouth workshop|a workshop]] at [[Dartmouth College]] in 1956.{{efn|\nDaniel Crevier wrote "the conference is generally recognized as the official birthdate of the new science."{{sfnp|Crevier|1993|pp=47\u201349}} [[Stuart J. Russell|Russell]] and [[Peter Norvig|Norvifg]] call the conference "the birth of artificial intelligence."{{sfnp|Russell|Norvig|2003|p=17}}}}<ref>\n[[Dartmouth workshop]]:\n* {{Harvtxt |Russell|Norvig|2003|p=17}}\n* {{Harvtxt|McCorduck|2004|pp=111\u2013136}}\n* {{Harvtxt|NRC||1999|pp=200\u2013201}}\nThe proposal:\n* {{Harvtxt|McCarthy|Minsky|Rochester|Shannon|1955}}\n</ref>\nThe attendees became the founders and leaders of AI research.{{efn|\n[[Stuart J. Russell|Russell]] and [[Peter Norvig|Norvig]] wrote "for the next 20 years the field would be dominated by these people and their students."{{sfnp|Russell|Norvig|2003|p=17}}\n}}\nThey and their students produced programs that the press described as "astonishing":{{efn|\n[[Stuart J. Russell|Russell]] and [[Peter Norvig|Norvig]] wrote "it was astonishing whenever a computer did anything kind of smartish".{{sfnp|Russell|Norvig|2003|p=18}}\n}}\ncomputers were learning [[draughts|checkers]] strategies, solving word problems in algebra, proving [[Theorem|logical theorems]] and speaking English.{{efn|\nThe programs described are [[Arthur Samuel]]'s checkers program for the [[IBM 701]], [[Daniel Bobrow]]'s [[STUDENT (computer program)|STUDENT]], [[Allen Newell|Newell]] and [[Herbert A. Simon|Simon]]'s [[Logic Theorist]] and [[Terry Winograd]]'s [[SHRDLU]].\n}}<ref>\nSuccessful [[Symbolic AI]] programs:\n* {{Harvtxt|McCorduck|2004|pp=243\u2013252}}\n* {{Harvtxt|Crevier|1993|pp=52\u2013107}}\n* {{Harvtxt|Moravec|1988|p=9}}\n* {{Harvtxt|Russell|Norvig|2003|pp=18\u201321}}\n</ref>\nBy the middle of the 1960s, research in the U.S. was heavily funded by the [[DARPA|Department of Defense]]<ref>\nAI heavily funded in 1960s:\n* {{Harvtxt|McCorduck|2004|p=131}}\n* {{Harvtxt|Crevier|1993|pp=51, 64\u201365}}\n* {{Harvtxt|NRC|1999|pp=204\u2013205}}\n</ref>\nand laboratories had been established around the world.{{sfnp|Howe|1994}}\n\n<!-- 1960s -->\nResearchers in the 1960s and the 1970s were convinced that symbolic approaches would eventually succeed in creating a machine with [[artificial general intelligence]] and considered this the goal of their field.{{sfnp|Newquist|1994|pp=86\u201386}}\n[[Herbert A. Simon|Herbert Simon]] predicted, "machines will be capable, within twenty years, of doing any work a man can do".<ref>\n{{Harvtxt|Simon|1965|p=96}} quoted in {{Harvtxt|Crevier|1993|p=109}}\n</ref>\n[[Marvin Minsky]] agreed, writing, "within a generation ... the problem of creating 'artificial intelligence' will substantially be solved".<ref>\n{{Harvtxt|Minsky|1967|p=2}} quoted in {{Harvtxt|Crevier|1993|p=109}}\n</ref>\n\n<!-- 1970s -->\nThey failed to recognize the difficulty of some of the remaining tasks. Progress slowed and in 1974, in response to the [[Lighthill report|criticism]] of [[Sir James Lighthill]]{{sfnp|Lighthill|1973}}\nand ongoing pressure from the US Congress to [[Mansfield Amendment|fund more productive projects]], both the U.S. and British governments cut off exploratory research in AI. The next few years would later be called an "[[AI winter]]", a period when obtaining funding for AI projects was difficult.\n<ref name="First AI winter">\nFirst [[AI Winter]], [[Lighthill report]], [[Mansfield Amendment]]\n* {{Harvtxt|Crevier|1993|pp=115\u2013117}}\n* {{Harvtxt|Russell|Norvig|2003|p=22}}\n* {{Harvtxt|NRC|1999|pp=212\u2013213}}\n* {{Harvtxt|Howe|1994}}\n* {{Harvtxt|Newquist|1994|pp=189\u2013201}}\n</ref>\n\n<!-- 1980s -->\nIn the early 1980s, AI research was revived by the commercial success of [[expert system]]s,<ref>\n[[Expert systems]]:\n* {{Harvtxt|Russell|Norvig|2003|pp=22\u201324}}\n* {{Harvtxt|Luger|Stubblefield|2004|pp=227\u2013331}}\n* {{Harvtxt|Nilsson|1998|loc=chpt. 17.4}}\n* {{Harvtxt|McCorduck|2004|pp=327\u2013335, 434\u2013435}}\n* {{Harvtxt|Crevier|1993|pp=145\u201362, 197\u2013203}}\n* {{Harvtxt|Newquist|1994|pp=155\u2013183}}\n</ref>\na form of AI program that simulated the knowledge and analytical skills of human experts. By 1985, the market for AI had reached over a billion dollars. At the same time, Japan's [[fifth generation computer]] project inspired the U.S and British governments to restore funding for [[academic research]].<ref name="AI in the 80s">\nFunding initiatives in the early 80s: [[Fifth Generation Project]] (Japan), [[Alvey]] (UK), [[Microelectronics and Computer Technology Corporation]] (US), [[Strategic Computing Initiative]] (US):\n* {{Harvtxt|McCorduck|2004|pp=426\u2013441}}\n* {{Harvtxt|Crevier|1993|pp=161\u2013162,197\u2013203, 211, 240}}\n* {{Harvtxt|Russell|Norvig|2003|p=24}}\n* {{Harvtxt|NRC|1999|pp=210\u2013211}}\n* {{Harvtxt|Newquist|1994|pp=235\u2013248}}\n</ref>\nHowever, beginning with the collapse of the [[Lisp Machine]] market in 1987, AI once again fell into disrepute, and a second, longer-lasting winter began.<ref name="Second AI winter">\nSecond [[AI Winter]]:\n* {{Harvtxt|McCorduck|2004|pp=430\u2013435}}\n* {{Harvtxt|Crevier|1993|pp=209\u2013210}}\n* {{Harvtxt|NRC|1999|pp=214\u2013216}}\n* {{Harvtxt|Newquist|1994|pp=301\u2013318}}\n</ref>\n\n<!-- SUBSYMBOLIC APPROACHES, 1980s -->\nMany researchers began to doubt that the [[Symbolic AI|symbolic approach]] would be able to imitate all the processes of human cognition, especially [[machine perception|perception]], robotics, [[machine learning|learning]] and [[pattern recognition]]. A number of researchers began to look into "sub-symbolic" approaches to specific AI problems.{{sfnp|Nilsson|1998|p=7}} [[Robotics]] researchers, such as [[Rodney Brooks]], rejected symbolic AI and focused on the basic engineering problems that would allow robots to move, survive, and learn their environment.{{efn|\n[[embodied mind|Embodied]] approaches to AI{{sfnp|McCorduck|2004|pp=454\u2013462}} were championed by [[Hans Moravec]]{{sfnp|Moravec|1988}} and [[Rodney Brooks]]{{sfnp|Brooks|1990}} and went by many names: [[Nouvelle AI]],{{sfnp|Brooks|1990}} [[Developmental robotics]],<ref name = "Developmental robotics">\n[[Developmental robotics]]:\n* {{Harvtxt|Weng|McClelland|Pentland|Sporns|2001}}\n* {{Harvtxt|Lungarella|Metta|Pfeifer|Sandini|2003}} \n* {{Harvtxt|Asada|Hosoda|Kuniyoshi|Ishiguro|2009}}\n* {{Harvtxt|Oudeyer|2010}}\n</ref>\n[[situated]] AI, [[behavior-based AI]] as well as others. A similar movement in cognitive science was the [[embodied mind thesis]].\n}}\nInterest in [[Artificial neural network|neural networks]] and "[[connectionism]]" was revived by [[Geoffrey Hinton]], [[David Rumelhart]] and others in the middle of the 1980s.<ref>\nRevival of connectionism:\n* {{Harvtxt|Crevier|1993|pp=214\u2013215}}\n* {{Harvtxt|Russell|Norvig|2003|p=25}}\n</ref>\n[[Soft computing]] tools were developed in the 80s, such as [[Artificial neural network|neural networks]], [[fuzzy system]]s, [[Grey system theory]], [[evolutionary computation]] and many tools drawn from [[statistics]] or [[mathematical optimization]].\n\n<!-- FORMAL METHODS RISING IN THE 1990s: "Statistical AI"  -->\nAI gradually restored its reputation in the late 1990s and early 21st century by finding specific solutions to specific problems. The narrow focus allowed researchers to produce verifiable results, exploit more  mathematical methods, and collaborate with other fields (such as [[statistics]], [[economics]] and [[mathematical optimization|mathematics]]).<ref name="AI 1990s">\n[[#Neats vs. scruffies|Formal]] and [[#Narrow vs. general AI|narrow]] methods adopted in the 1990s:\n* {{Harvtxt |Russell|Norvig|2003|pp=25\u201326}}\n* {{Harvtxt|McCorduck|2004|pp=486\u2013487}}\n</ref>\nBy 2000, solutions developed by AI researchers were being widely used, although in the 1990s they were rarely described as "artificial intelligence".<ref name="AI widely used 1990s">\nAI widely used in late 1990s:\n* {{Harvtxt|Russell|Norvig|2003|p=28}}\n* {{Harvtxt|Kurzweil|2005|p=265}}\n* {{Harvtxt|NRC|1999|pp=216\u2013222}}\n* {{Harvtxt|Newquist|1994|pp=189\u2013201}}\n</ref>\n\n<!--DEEP LEARNING, BIG DATA & MACHINE LEARNING IN THE 2010s-present -->\n[[Moore's law|Faster computers]], algorithmic improvements, and access to [[big data|large amounts of data]] enabled advances in [[machine learning]] and perception; data-hungry [[deep learning]] methods started to dominate accuracy benchmarks [[Deep learning#Deep learning revolution|around 2012]].{{sfnp|McKinsey|2018}}\nAccording to [[Bloomberg News|Bloomberg's]] Jack Clark, 2015 was a landmark year for artificial intelligence, with the number of software projects that use AI within [[Google]] increased from a "sporadic usage" in 2012 to more than 2,700 projects.{{efn|\nClark wrote: "After a half-decade of quiet breakthroughs in artificial intelligence, 2015 has been a landmark year. Computers are smarter and learning faster than ever."{{sfnp|Clark|2015b}}\n}} He attributes this to an increase in affordable [[Artificial neural network|neural networks]], due to a rise in cloud computing infrastructure and to an increase in research tools and datasets.{{sfnp|Clark|2015b}} In a 2017 survey, one in five companies reported they had "incorporated AI in some offerings or processes".<ref>{{Harvtxt|MIT Sloan Management Review|2018}}; {{Harvtxt|Lorica|2017}}</ref> The amount of research into AI (measured by total publications) increased by 50% in the years 2015–2019.{{sfnp|UNESCO|2021}}\n\n<!-- AGI, 2005-present -->\nNumerous academic researchers became concerned that AI was no longer pursuing the original goal of creating versatile, fully intelligent machines. Much of current research involves statistical AI, which is overwhelmingly used to solve specific problems, even highly successful techniques such as [[deep learning]]. This concern has led to the subfield [[artificial general intelligence]] (or "AGI"), which had several well-funded institutions by the 2010s.<ref name="Artificial General Intelligence">\n{{Harvtxt|Pennachin|Goertzel|2007}}; {{Harvtxt|Roberts|2016}}\n</ref>"}},
{"article_title": "Applet", "pageid": "1202", "revid": "1054298975", "timestamp": "2021-11-09T06:31:13Z", "history_paths": [["Applet --- Introduction ---", "History"]], "categories": ["technology neologisms", "component-based software engineering", "java (programming language) libraries"], "heading_tree": {"Applet --- Introduction ---": {"History": {}, "Applet as an extension of other software": {"Web-based Applets": {}, "Applet Vs. Subroutine": {}}, "Java applets": {}, "Security": {"Open platform applets": {}, "Java applets": {}, "Web-based applets": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Applet --- Introduction ---|History": "The word ''applet'' was first used in 1990 in PC Magazine.<ref name="Origin">{{cite web\n|url=http://www.oed.com\n|title=Oxford English Dictionary\n|year=2011\n|access-date=2011-08-23\n| archive-url= https://web.archive.org/web/20110720020117/http://www.oed.com//| archive-date= 20 July 2011 | url-status= live}}</ref> However, the concept of an applet, or more broadly a small interpreted program downloaded and executed by the user, dates at least to RFC 5 (1969) by [[Jeff Rulifson]], which described the [[Decode-Encode Language]] (DEL), which was designed to allow remote use of the [[NLS (computer system)|oN-Line System]] (NLS) over [[ARPANET]], by downloading small programs to enhance the interaction.<ref>{{citation |title= DEL |author= Jeff Rulifson |work= RFC 5 |date= June 2, 1969 |publisher= Network Working Group }}</ref> This has been specifically credited as a forerunner of Java's downloadable programs in RFC 2555.<ref>{{citation |title= 30 Years of RFCs |author= RFC Editor, et a. |work= RFC 2555 |date= April 7, 1999 |publisher= Network Working Group }}</ref>"}},
{"article_title": "Acetylene", "pageid": "1778", "revid": "1062720195", "timestamp": "2021-12-30T03:30:33Z", "history_paths": [["Acetylene --- Introduction ---", "Discovery"]], "categories": ["acetylene", "alkynes", "fuel gas", "industrial gases", "synthetic fuel technologies", "explosive chemicals", "explosive gases"], "heading_tree": {"Acetylene --- Introduction ---": {"Discovery": {}, "Preparation": {}, "Bonding": {}, "Physical properties": {"Changes of state": {}, "Other": {}}, "Applications": {"Welding": {}, "Portable lighting": {}, "Plastics and acrylic acid derivatives": {}, "Niche applications": {}}, "Natural occurrence": {}, "Reactions": {"Vinylation: hydration, hydrohalogenation, and related reactions": {}, "Addition to formaldehyde": {}, "Carbonylation": {}, "Organometallic chemistry": {}, "Acid-base reactions": {}}, "Safety and handling": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Acetylene --- Introduction ---|Discovery": "Acetylene was discovered in 1836 by [[Edmund Davy]], who identified it as a "new carburet of hydrogen".<ref>Edmund Davy (August 1836) [https://books.google.com/books?id=grtZAAAAcAAJ&pg=RA1-PA62#v=onepage&q&f=false "Notice of a new gaseous bicarburet of hydrogen"], ''Report of the Sixth Meeting of the British Association for the Advancement of Science \u2026'', '''5''' :  62\u201363.</ref><ref>{{cite book|title=Acetylene: Its Properties, Manufacture and Uses|last1=Miller|first1=S. A.|year=1965|publisher=Academic Press Inc.|volume=1|url=https://books.google.com/books?id=-u1GAQAAIAAJ}}</ref> It was an accidental discovery while attempting to isolate [[potassium]] metal. By heating potassium carbonate with carbon at very high temperatures, he produced a residue of what is now known as potassium carbide, (K<sub>2</sub>C<sub>2</sub>), which reacted with water to release the new gas. It was rediscovered in 1860 by French chemist [[Marcellin Berthelot]], who coined the name ''ac\u00e9tyl\u00e8ne''.<ref>Bertholet (1860) [http://gallica.bnf.fr/ark:/12148/bpt6k3007r/f817.image "Note sur une nouvelle s\u00e9rie de compos\u00e9s organiques, le quadricarbure d'hydrog\u00e8ne et ses d\u00e9riv\u00e9s"] (Note on a new series of organic compounds, tetra-carbon hydride and its derivatives), ''Comptes rendus'', series 3, '''50''' :  805\u2013808.</ref>\nBerthelot's empirical formula for acetylene (C<sub>4</sub>H<sub>2</sub>), as well as the alternative name "quadricarbure d'hydrog\u00e8ne" (''hydrogen quadricarbide''), were incorrect because many chemists at that time used the wrong atomic mass for carbon (6 instead of 12).<ref>{{cite journal |last1=Ihde |first1=Aaron J. |title=The Karlsruhe Congress: A centennial retrospective |journal=Journal of Chemical Education |date=1961 |volume=38 |issue=2 |page=83 |url=https://pubs.acs.org/doi/abs/10.1021/ed038p83 |access-date=29 December 2021 |quote=Atomic weights of both 6 and 12 were both in use for carbon.}}</ref>\nBerthelot was able to prepare this gas by passing vapours of organic compounds (methanol, ethanol, etc.) through a red hot tube and collecting the [[effluent]]. He also found that acetylene was formed by sparking electricity through mixed [[cyanogen]] and [[hydrogen]] gases. Berthelot later obtained acetylene directly by passing hydrogen between the poles of a [[arc lamp|carbon arc]].<ref>Berthelot (1862) [http://gallica.bnf.fr/ark:/12148/bpt6k30115/f640.image.langEN "Synth\u00e8se de l'ac\u00e9tyl\u00e8ne par la combinaison directe du carbone avec l'hydrog\u00e8ne"] (Synthesis of acetylene by the direct combination of carbon with hydrogen), ''Comptes rendus'', series 3, '''54''' :  640\u2013644.</ref><ref>[http://chestofbooks.com/crafts/metal/Welding-Cutting/Acetylene.html Acetylene].</ref>"}},
{"article_title": "Active Directory", "pageid": "2807", "revid": "1062066427", "timestamp": "2021-12-26T01:46:07Z", "history_paths": [["Active Directory --- Introduction ---", "History"]], "categories": ["active directory", "directory services", "microsoft server technology", "windows components", "windows 2000"], "heading_tree": {"Active Directory --- Introduction ---": {"History": {}, "Active Directory Services": {"Domain Services": {}, "{{anchor|ADAM}} Lightweight Directory Services": {}, "Certificate Services": {}, "Federation Services": {}, "Rights Management Services": {}}, "Logical structure": {"Objects": {}, "Forests, trees, and domains": {"Organizational units": {"Shadow groups": {}}}, "Partitions": {}}, "Physical structure": {"Replication": {}}, "Implementation": {}, "Database": {}, "Trusting": {"Terminology": {}}, "Management solutions": {}, "Unix integration": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Active Directory --- Introduction ---|History": "Like many information-technology efforts, originated out of a [[Democratization#Design, products and services|democratization of design]] using [[Request for Comments]] (RFCs). The [[Internet Engineering Task Force]] (IETF), which oversees the RFC process, has accepted numerous RFCs initiated by widespread participants. For example, LDAP underpins Active Directory. Also [[X.500]] directories and the [[Organizational Unit]] preceded the Active Directory concept that makes use of those methods. The LDAP concept began to emerge even before the founding of Microsoft in April 1975, with RFCs as early as 1971. RFCs contributing to LDAP include RFC 1823 (on the LDAP API, August 1995),<ref>{{cite web|title=The LDAP Application Program Interface|url=http://www.ietf.org/rfc/rfc1823.txt|last1=Howes|first1=T.|last2=Smith|first2=M.|date=August 1995|website=The Internet Engineering Task Force (IETF)|url-status=live|archive-url=https://web.archive.org/web/20200430164500/https://www.ietf.org/rfc/rfc1823.txt|archive-date=2020-04-30|access-date=2013-11-26}}</ref> RFC 2307, RFC 3062, and RFC 4533.<ref>{{cite web|title=An Approach for Using LDAP as a Network Information Service|url=http://www.ietf.org/rfc/rfc2307.txt|last=Howard|first=L.|date=March 1998|website=Internet Engineering Task Force (IETF)|url-status=live|archive-url=https://web.archive.org/web/20200430164234/https://www.ietf.org/rfc/rfc2307.txt|archive-date=30 April 2020|access-date=26 November 2013}}</ref><ref>{{cite web|title=LDAP Password Modify Extended Operation|url=http://www.ietf.org/rfc/rfc3062.txt|last=Zeilenga|first=K.|date=February 2001|website=The Internet Engineering Task Force (IETF)|url-status=live|archive-url=https://web.archive.org/web/20200430194523/https://www.ietf.org/rfc/rfc3062.txt|archive-date=30 April 2020|access-date=26 November 2013}}</ref><ref>{{cite web|title=The Lightweight Directory Access Protocol (LDAP) Content Synchronization Operation|url=http://www.ietf.org/rfc/rfc4533.txt|last1=Zeilenga|first1=K.|last2=Choi|first2=J.H.|date=June 2006|website=The Internet Engineering Task Force (IETF)|url-status=live|archive-url=https://web.archive.org/web/20200430194756/https://www.ietf.org/rfc/rfc4533.txt|archive-date=30 April 2020|access-date=26 November 2013}}</ref>\n\nMicrosoft previewed Active Directory in 1999, released it first with [[Windows 2000]] Server edition, and revised it to extend functionality and improve administration in [[Windows Server 2003]]. Active Directory support was also added to Windows 95, Windows 98 and Windows NT 4.0 via patch, with some features being unsupported.<ref>{{Cite web|title=Active Directory Client (dsclient) for Win98/NT|url=https://petri.com/dsclient_for_win98_nt|author=Daniel Petri|date=January 8, 2009}}</ref><ref>{{Cite web|title=Dsclient.exe connects Windows 9x/NT PCs to Active Directory|url=https://www.techrepublic.com/article/dsclientexe-connects-windows-9x-nt-pcs-to-active-directory/}}</ref> Additional improvements came with subsequent versions of [[Windows Server]]. In [[Windows Server 2008]], additional services were added to Active Directory, such as [[Active Directory Federation Services]].<ref name=":0">{{Cite web|title=Windows Server 2008 - New Features|url=http://www.computerperformance.co.uk/Longhorn/longhorn_new_features.htm|last=Thomas|first=Guy|date=29 November 2000|website=ComputerPerformance.co.uk|publisher=Computer Performance Ltd|url-status=live|archive-url=https://web.archive.org/web/20190902044655/https://www.computerperformance.co.uk/longhorn/longhorn-new-features/|archive-date=2 September 2019|access-date=30 April 2020}}</ref> The part of the directory in charge of management of domains, which was previously a core part of the operating system,<ref name=":0" /> was renamed Active Directory Domain Services (ADDS) and became a server role like others.<ref name=":1">{{Cite web|title=The Future of Windows: Directory Services in Windows Server "Longhorn"|url=https://technet.microsoft.com/en-us/magazine/2006.11.futureofwindows.aspx|last=Hynes|first=Byron|date=November 2006|website=[[TechNet Magazine]]|publisher=[[Microsoft]]|url-status=live|archive-url=https://web.archive.org/web/20200430162954/https://docs.microsoft.com/en-us/previous-versions/technet-magazine/cc160894(v=msdn.10)?redirectedfrom=MSDN|archive-date=30 April 2020|access-date=30 April 2020}}</ref> "Active Directory" became the umbrella title of a broader range of directory-based services.<ref>{{Cite web|url = https://technet.microsoft.com/en-us/library/dn268294.aspx|title = What's New in Active Directory in Windows Server|website = Windows Server 2012 R2 and Windows Server 2012 Tech Center|publisher = [[Microsoft]]}}</ref> According to Byron Hynes, everything related to identity was brought under Active Directory's banner.<ref name=":1" />"}},
{"article_title": "Active Server Pages", "pageid": "2883", "revid": "1061349664", "timestamp": "2021-12-21T05:06:20Z", "history_paths": [["Active Server Pages --- Introduction ---", "History"]], "categories": ["microsoft server technology"], "heading_tree": {"Active Server Pages --- Introduction ---": {"History": {}, "Architecture": {"The Server object": {}, "The Application object": {}, "The Session object": {}, "The Err object": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Active Server Pages --- Introduction ---|History": "Initially released as an add-on to [[Internet Information Services]] (IIS) via the [[Windows NT 4.0#Option Pack|Windows NT 4.0 Option Pack]] (ca. 1996), it is included as a component of [[Windows Server]] (since the initial release of [[Windows 2000 Server]]). There have been three versions of ASP, each introduced with different versions of IIS:\n\n* ASP 1.0 was released in December 1996 as part of IIS 3.0\n* ASP 2.0 was released in September 1997 as part of IIS 4.0\n* ASP 3.0 was released in November 2000 as part of IIS 5.0\n\nASP 2.0 provides six built-in [[Object (computer science)|objects]]: Application, ASPError, Request, Response, Server, and Session. <code>Session</code> object, for example, represents a [[Session (computer science)|session]] that maintains the state of [[Variable (programming)|variables]] from page to page.<ref>The session data is kept server-side, the ID is saved as a [[HTTP Cookie]]. Source: [http://msdn.microsoft.com/en-us/library/ms972338.aspx ASP and Web Session Management], Microsoft</ref> The [[Active Scripting]] engine's support of the [[Component Object Model]] (COM) enables ASP [[website]]s to access functionality in compiled [[Library (computing)|libraries]] such as [[Dynamic-link library|DLLs]].\n\nASP 3.0 does not differ greatly from ASP 2.0 but it does offer some additional enhancements such as Server.Transfer method, Server.Execute method, and an enhanced ASPError object. ASP 3.0 also enables buffering by default and optimized the engine for better performance.\n\nASP was supported until 14 January 2020 on [[Windows 7]].<ref name=":0">{{cite web|title=Active Server Pages (ASP) support in Windows|url=https://support.microsoft.com/en-us/kb/2669020|website=Support|publisher=[[Microsoft]]|access-date=11 August 2015|date=30 January 2012|edition=4.0}}</ref> The use of ASP pages will be supported on [[Windows 8]] for a minimum of 10 years from the [[Windows 8]] release date.<ref name=":0" /> ASP is currently supported in all available versions of IIS.<ref>Source: [https://support.microsoft.com/en-gb/help/2669020/active-server-pages-asp-support-in-windows], Microsoft</ref>"}},
{"article_title": "Atom probe", "pageid": "3211", "revid": "1062365142", "timestamp": "2021-12-28T01:24:24Z", "history_paths": [["Atom probe --- Introduction ---", "History"]], "categories": ["scientific techniques", "microscopes", "nanotechnology"], "heading_tree": {"Atom probe --- Introduction ---": {"Overview": {}, "History": {"Field ion microscopy": {}, "10-cm Atom Probe": {}, "Imaging Atom Probe": {}, "Atom Probe Tomography (APT)": {}}, "Theory": {"Field evaporation": {}, "Ion flight": {}, "Magnification": {}, "Reconstruction": {}, "Data features": {}}, "Systems": {"System layout": {}, "Performance": {}}, "Applications": {"Metallurgy": {}, "Semiconductors": {}}, "Limitations": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Atom probe --- Introduction ---|History": "{{main|Field ion microscopy}}\nField ion microscopy is a modification of [[field emission microscopy]] where a stream of tunneling electrons is emitted from the apex of a sharp needle-like ''tip'' cathode when subjected to a sufficiently high electric field (~3-6 V/nm).<ref name="Gomer">{{cite book|title=Field emission and field ionization|author=Gomer, R|publisher=Harvard University Press|year=1961|isbn=978-1-56396-124-3}}</ref> The needle is oriented towards a phosphor screen to create a projected image of the [[work function]] at the tip apex. The image resolution is limited to (2-2.5 nm), due to quantum mechanical effects and lateral variations in the electron velocity.<ref name="Tsong">{{cite book|author=Tsong, T| title=Atom probe field Ion Microscopy: Field Ion emission and Surfaces and interfaces at atomic resolution|year=1990|publisher=Cambridge University Press|isbn=978-0-521-36379-2}}</ref>\n\nIn field ion microscopy the tip is cooled by a cryogen and its polarity is reversed. When an ''imaging gas'' (usually hydrogen or helium) is introduced at low pressures (< 0.1 Pascal) gas ions in the high electric field at the tip apex are ''field ionized'' and produce a projected image of protruding atoms at the tip apex. The image resolution is determined primarily by the temperature of the tip but even at 78 Kelvin atomic resolution is achieved.<ref>{{cite journal|last1=M\u00fcller|first1=Erwin W.|first2=Kanwar|last2=Bahadur|year=1956|title= Field Ionization of gases at a metal surface and the resolution of the field ion microscope |journal= Phys. Rev. |volume=102|issue=1|pages=624\u2013631|bibcode = 1956PhRv..102..624M |doi = 10.1103/PhysRev.102.624 }}</ref>\n\n The '''10-cm Atom Probe''', invented in 1973 by [[J. A. Panitz]]<ref>{{cite journal |last=Panitz |first=John A. |year=1973 |title=The 10 cm Atom Probe |journal=Review of Scientific Instruments |volume=44 |issue=8 |pages=1034\u20131038 |doi=10.1063/1.1686295 |bibcode=1973RScI...44.1034P }}</ref> was a \u201cnew and simple atom probe which permits rapid, in depth species identification or the more usual atom-by atom analysis provided by its predecessors ... in an instrument having a volume of less than two liters in which tip movement is unnecessary and the problems of evaporation pulse stability and alignment common to previous designs have been eliminated.\u201d This was accomplished by combining a [[Time-of-flight mass spectrometry|time of flight (TOF) mass spectrometer]] with a proximity focussed, dual channel plate detector, an 11.8 cm drift region and a 38\u00b0 field of view. An FIM image or a desorption image of the atoms removed from the apex of a field emitter tip could be obtained. The 10-cm Atom Probe has been called the ''progenitor'' of later atom probes including the commercial instruments.<ref>{{cite journal |last=Seidman |first=David N. |year=2007 |title=Three-Dimensional Atom-Probe Tomography: Advances and Applications |journal=[[Annual Review of Materials Research]] |volume=37 |pages=127\u2013158 |doi=10.1146/annurev.matsci.37.052506.084200 |bibcode=2007AnRMS..37..127S }}</ref>\n\n The '''Imaging Atom-Probe''' ('''IAP''') was introduced in 1974 by [[J. A. Panitz]]. It incorporated the features of the 10-cm Atom-Probe yet \u201c... departs completely from [previous] atom probe philosophy. Rather than attempt to determine the identity of a surface species producing a preselected ion-image spot, we wish to determine the complete crystallographic distribution of a surface species of preselected mass-to-charge ratio. Now suppose that instead of operating the [detector] continuously, it is turned on for a short time coincidentally with the arrival of a preselected species of interest by applying a ''gate pulse'' a time T after the evaporation pulse has reached the specimen. If the duration of the gate pulse is shorter than the travel time between adjacent species, only that surface species having the unique travel time T will be detected and its complete crystallographic distribution displayed.\u201d <ref>{{cite journal|last=Panitz|first=John A.|author-link=J. A. Panitz|year=1974|title=The Crystallographic Distribution of Field-Desorbed Species|journal=Journal of Vacuum Science and Technology|volume=11|issue=1|pages=207\u2013210|issn=0022-5355|doi=10.1116/1.1318570|bibcode = 1974JVST...11..206P }}</ref> It was patented in 1975 as the '''Field Desorption Spectrometer'''.<ref>{{cite journal |last=Panitz |first=John A.|title=Field Desorption Spectrometer |journal=U.S. Patent 3,868,507 }}</ref> The Imaging Atom-Probe moniker was coined by A. J. Waugh in 1978 and the instrument was described in detail by J. A. Panitz in the same year.<ref>{{cite journal |last=Waugh |first=A. J. |year=1978 |title=An imaging atom probe using a single time-gated channel plate |journal=J. Phys. E: Sci. Instrum. |volume=11|issue=1 |pages=49\u201352|bibcode = 1978JPhE...11...49W |doi = 10.1088/0022-3735/11/1/012 }}</ref><ref>{{cite journal|last=Panitz|first=John A.|author-link=J. A. Panitz|year=1978|title=Imaging Atom-Probe Mass Spectroscopy|journal=Progress in Surface Science|volume=8|issue=6|pages=219\u2013263|issn=0079-6816|doi=10.1016/0079-6816(78)90002-3|bibcode = 1978PrSS....8..219P }}</ref>\n\n Modern day atom probe tomography (APT) uses a position-sensitive detector to deduce the lateral location of atoms. The idea of the APT, inspired by J. A. Panitz's ''Field Desorption Spectrometer'' patent, was developed by Mike Miller starting in 1983 and culminated with the first prototype in 1986.<ref name="Miller"/> Various refinements were made to the instrument, including the use of a so-called position-sensitive (PoS) detector by Alfred Cerezo, Terence Godfrey, and George D. W. Smith at Oxford University in 1988. The Tomographic Atom Probe (TAP), developed by researchers at the University of Rouen in France in 1993, introduced a multichannel timing system and multianode array. Both instruments (PoSAP and TAP) were commercialized by [[Oxford Instruments|Oxford Nanoscience]] and [[CAMECA]] respectively. Since then, there have been many refinements to increase the field of view, mass and position resolution, and data acquisition rate of the instrument. The Local Electrode Atom Probe was first introduced in 2003 by Imago Scientific Instruments. In 2005, the commercialization of the pulsed laser atom probe (PLAP) expanded the avenues of research from highly conductive materials (metals) to poor conductors (semiconductors like silicon) and even insulating materials.<ref>{{cite journal|last1=Bunton|first1=J.|last2=Lenz|first2=D|last3=Olson|first3=J|last4=Thompson|first4=K|last5=Ulfig|first5=R|last6=Larson|first6=D|last7=Kelly|first7=T|title=Instrumentation Developments in Atom Probe Tomography: Applications in Semiconductor Research|journal=Microscopy and Microanalysis |year=2006|volume=12|issue=2|pages=1730\u20131731|issn=1431-9276|doi=10.1017/S1431927606065809|bibcode = 2006MiMic..12.1730B |doi-access=free}}</ref> [[AMETEK]] acquired [[CAMECA]] in 2007 and [[Imago Scientific Instruments]] (Madison, WI) in 2010, making the company the sole commercial developer of APTs with more than 110 instruments installed around the world in 2019.\n\nThe first few decades of work with APT focused on metals. However, with the introduction of the laser pulsed atom probe systems applications have expanded to semiconductors, ceramic and geologic materials, with some work on biomaterials.<ref name=annrev>{{Cite journal \n| last1 = Kelly | first1 = T. F. \n| last2 = Larson | first2 = D. J. \n| doi = 10.1146/annurev-matsci-070511-155007 \n| title = Atom Probe Tomography 2012 \n| journal = [[Annual Review of Materials Research]] \n| volume = 42 \n| pages = 1\u201331 \n| year = 2012 \n|bibcode = 2012AnRMS..42....1K }}</ref> The most advanced study of biological material to date using APT<ref name=annrev/> involved analyzing the chemical structure of teeth of the [[radula]] of [[chiton]] ''[[Chaetopleura apiculata]]''.<ref name="Gordon 2011">{{cite journal | last1 = Gordon | first1 = L. M. | last2 = Joester | first2 = D. | year = 2011 | title = Nanoscale chemical tomography of buried organic\u2013inorganic interfaces in the chiton tooth | journal = [[Nature (journal)|Nature]] | volume = 469 | issue = 7329| pages = 194\u2013197 | doi = 10.1038/nature09686 |bibcode = 2011Natur.469..194G | pmid=21228873| s2cid = 4430261 }}</ref> In this study, the use of APT showed chemical maps of organic fibers in the surrounding nano-crystalline [[magnetite]] in the chiton teeth, fibers which were often co-located with [[sodium]] or [[magnesium]].<ref name="Gordon 2011"/> This has been furthered to study [[elephant tusks]], [[dentin]]<ref>{{cite journal|author=Gordon, L.M. |author2=Tran, L. |author3=Joester, D. |title=Atom Probe Tomography of Apatites and Bone-Type Mineralized Tissues|journal=ACS Nano|volume=6 |issue=12 |date=2012|doi=10.1021/nn3049957|pmid=23176319 |pages=10667\u201310675}}</ref> and human [[Tooth enamel|enamel]].<ref>{{Cite journal|last1=Fontaine|first1=Alexandre La|last2=Cairney|first2=Julie|date=July 2017|title=Atom Probe Tomography of Human Tooth Enamel and the Accurate Identification of Magnesium and Carbon in the Mass Spectrum|journal=Microscopy and Microanalysis|language=en|volume=23|issue=S1|pages=676\u2013677|doi=10.1017/S1431927617004044|bibcode=2017MiMic..23S.676L|issn=1431-9276|doi-access=free}}</ref>"}},
{"article_title": "Braille", "pageid": "3933", "revid": "1060167116", "timestamp": "2021-12-13T21:15:43Z", "history_paths": [["Braille --- Introduction ---", "History"]], "categories": ["braille", "1824 introductions", "assistive technology", "augmentative and alternative communication", "character sets", "digital typography", "french inventions", "latin-script representations", "writing systems introduced in the 19th century"], "heading_tree": {"Braille --- Introduction ---": {"History": {"Derivation": {}, "Assignment": {}}, "Form": {}, "Writing braille": {"Eight-dot braille": {}, "Letters": {}, "Formatting": {}, "Punctuation": {}, "Contractions": {}, "Page dimensions": {}, "Braille writing machine": {}}, "Braille reading": {}, "Literacy": {"U.S. braille literacy statistics": {}, "United Kingdom": {}}, "Braille transcription": {}, "Braille translation software": {}, "Braille reading techniques": {}, "International uniformity": {}, "Other braille conventions": {}, "Uses": {"Currency": {}}, "Unicode": {}, "Observation": {}, "Braille devices": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Braille --- Introduction ---|History": "[[File:DSC 4050-MR-Braille.jpg|thumb|The Braille code where the word {{lang|fr-Brai|{{bc|\u280f|\u2817|\u2811|\u280d|\u280a|\u2811|\u2817}}}} ({{wiktfr|premier}}, [[French language|French]] for "first") can be read.]]\nBraille was based on a tactile military [[code]] called [[night writing]], developed by [[Charles Barbier]] in response to [[Napoleon]]'s demand for a means for soldiers to communicate silently at night and without a light source.<ref>{{cite web |title=What is Braille|url=http://www.afb.org/info/living-with-vision-loss/braille/what-is-braille/123|website=American Foundation for the Blind}}</ref> In Barbier's system, sets of 12 embossed dots encoded 36 different sounds. It proved to be too difficult for soldiers to recognize by touch and was rejected by the military. In 1821 Barbier visited the Royal Institute for the Blind in [[Paris]], where he met Louis Braille. Braille identified three major defects of the code: first, the symbols represented phonetic sounds and not letters of the alphabet{{snd}}  thus the code was unable to render the orthography of the words. Second, the 12-dot symbols could not easily fit beneath the pad of the reading finger. This required the reading finger to move in order to perceive the whole symbol which slowed the reading process. Third, the code did not include symbols for numerals or punctuation. Braille's solution was to use 6-dot cells and to assign a specific pattern to each letter of the alphabet. Braille also  developed symbols for representing numerals and punctuation.<ref name=" No\u00eblle Roy ">{{Citation\n | url = http://www.avh.asso.fr/download.php?chemin=rubriques/association/dwnld/&filename=Bio_Br_Paris_GB_060109.pdf\n | title = Louis Braille 1809\u20131852, a French genius\n | last = Roy |first = No\u00eblle\n | website = Valentin Ha\u00fcy Association\n | access-date = 2011-02-05\n | url-status = dead\n | archive-url = https://web.archive.org/web/20101010054505/http://www.avh.asso.fr/download.php?chemin=rubriques%2Fassociation%2Fdwnld%2F&filename=Bio_Br_Paris_GB_060109.pdf\n | archive-date = 10 October 2010 }}</ref>\nAt first, Braille was a one-to-one transliteration of the French alphabet, but soon various abbreviations (contractions) and even [[logogram]]s were developed, creating a system much more like shorthand.<ref name=digital/> \n\nToday, there are braille codes for over 133 languages.<ref name="WorldBrailleUsage">{{Citation  \n|last1 = Perkins\n|last2 = International Council on English Braille \n|last3 = National Library Service for the Blind and Physically Handicapped, Library of Congress \n|last4 = UNESCO\n|year = 2013\n|title = World Braille Usage\n|edition = 3rd\n|publisher = Perkins\n|url = https://www.perkins.org/resource/world-braille-usage/}}</ref> \n\nIn English, some variations in the braille codes have traditionally existed among English-speaking countries. In 1991, work to standardize the braille codes used in the English speaking world began. [[Unified English Braille]] (UEB) has been adopted in all 7 member countries of the International Council on English Braille (ICEB) as well as Nigeria.<ref>{{cite web |title=Unified English Braille |url=http://www.iceb.org/ueb.html |website=International Council on English Braille |access-date=1 December 2021}}</ref>  \n\nFor blind readers, Braille is an independent writing system, rather than a code of printed orthography.<ref name="D&B"/>\n\n Braille is derived from the Latin alphabet, albeit indirectly. In Braille's original system, the dot patterns were assigned to letters according to their position within the [[collating sequence|alphabetic order]] of the French alphabet, with [[diacritic|accented]] letters and ''w'' sorted at the end.<ref>{{cite book |first=Madeleine Seymour |last=Loomis |date=1942 |title=The Braille Reference Book for Grades I, I.5, and II |location=New York and London |publisher=Harper & Bros. |oclc=13839990}}</ref>\n\nUnlike print which consists of mostly arbitrary symbols, the braille alphabet follows a logical sequence. The first ten letters of the alphabet, ''a\u2013j,'' use the upper four dot positions: {{Braille cell|type=text|\u2801|\u2803|\u2809|\u2819|\u2811|\u280b|\u281b|\u2813|\u280a|\u281a}} (black dots in the table below). These stand for the ten digits ''1\u20139'' and ''0'' in an [[alphabetic numeral system]] similar to [[Greek numerals]] (as well all derivations of it, including [[Hebrew numerals]], [[Cyrillic numerals]], [[Abjad numerals]], also Hebrew [[gematria]] and Greek [[isopsephy]]).\n\nThough the dots are assigned in no obvious order, the cells with the fewest dots are assigned to the first three letters (and lowest digits), ''abc = 123'' ({{Braille cell|type=text|\u2801|\u2803|\u2809}}), and to the three vowels in this part of the alphabet, ''aei'' ({{Braille cell|type=text|\u2801|\u2811|\u280a}}), whereas the even digits, ''4, 6, 8, 0'' ({{Braille cell|type=text|\u2819|\u280b|\u2813|\u281a}}), are corners/right angles.\n\nThe next ten letters, ''k\u2013t,'' are identical to ''a\u2013j,'' respectively, apart from the addition of a dot at position 3 (red dots in the table below): {{Braille cell|type=text|\u2805|\u2807|\u280d|\u281d|\u2815|\u280f|\u281f|\u2817|\u280e|\u281e}}:\n\n{|class=wikitable\n|+Derivation (colored dots) of the 26 braille letters of the [[ISO basic Latin alphabet|Basic Latin alphabet]]<br />from the 10 numeric digits (black dots)\n|- align=center\n|[[File:Braille A1.svg|40px]]||[[File:Braille B2.svg|40px]]||[[File:Braille C3.svg|40px]]||[[File:Braille D4.svg|40px]]||[[File:Braille E5.svg|40px]]||[[File:Braille F6.svg|40px]]||[[File:Braille G7.svg|40px]]||[[File:Braille H8.svg|40px]]||[[File:Braille I9.svg|40px]]||[[File:Braille J0.svg|40px]]\n|- align=center\n|[[a]]/[[1 (number)|1]]||[[b]]/[[2 (number)|2]]||[[c]]/[[3 (number)|3]]||[[d]]/[[4 (number)|4]]||[[e]]/[[5 (number)|5]]||[[f]]/[[6 (number)|6]]||[[g]]/[[7 (number)|7]]||[[h]]/[[8 (number)|8]]||[[i]]/[[9 (number)|9]]||[[j]]/[[0 (number)|0]]\n|- align=center\n|[[File:Braille K colored.svg|40px]]||[[File:Braille L colored.svg|40px]]||[[File:Braille M colored.svg|40px]]||[[File:Braille N colored.svg|40px]]||[[File:Braille O colored.svg|40px]]||[[File:Braille P colored.svg|40px]]||[[File:Braille Q colored.svg|40px]]||[[File:Braille R colored.svg|40px]]||[[File:Braille S colored.svg|40px]]||[[File:Braille T colored.svg|40px]]\n|- align=center\n|[[k]]||[[l]]||[[m]]||[[n]]||[[o]]||[[p]]||[[q]]||[[r]]||[[s]]||[[t]]\n|- align=center\n|[[File:Braille U colored.svg|40px]]||[[File:Braille V colored.svg|40px]]||[[File:Braille X colored.svg|40px]]||[[File:Braille Y colored.svg|40px]]||[[File:Braille Z colored.svg|40px]]|| colspan="4" rowspan="2" | ||[[File:Braille W colored.svg|40px]]\n|- align=center\n|[[u]]||[[v]]||[[x]]||[[y]]||[[z]]||[[w]]\n|}\n\nThe next ten letters (the next "[[wikt:decade#English|decade]]") are the same again, but with dots also at both position 3 and position 6 (green dots in the table above). Here ''w'' was initially left out as not being a part of the official French alphabet at the time of Braille's life; the French braille order is ''u v x y z \u00e7 \u00e9 \u00e0 \u00e8 \u00f9'' ({{Braille cell|type=text|\u2825|\u2827|\u282d|\u283d|\u2835|\u282f|\u283f|\u2837|\u282e|\u283e}}).{{NoteTag|The values of the Latin letters after ''z'' differ from language to language; these are Braille's assignments for rendering French.}}\n\nThe next ten letters, ending in ''w'', are the same again, except that for this series position 6 (purple dot in the table above) is used without a dot at position 3. In French braille these are the letters ''\u00e2 \u00ea \u00ee \u00f4 \u00fb \u00eb \u00ef \u00fc \u00f6 w'' ({{Braille cell|type=text|\u2821|\u2823|\u2829|\u2839|\u2831|\u282b|\u283b|\u2833|\u282a|\u283a}}). ''W'' had been tacked onto the end of 39 letters of the French alphabet to accommodate English.\n\nThe ''a\u2013j'' series shifted down by one dot space ({{Braille cell|type=text|\u2802|\u2806|\u2812|\u2832|\u2822|\u2816|\u2836|\u2826|\u2814|\u2834}}) is used for punctuation.  Letters ''a'' {{bc|a}} and ''c'' {{bc|c}}, which only use dots in the top row, were shifted two places for the apostrophe and hyphen: {{Braille cell|type=text|\u2804|\u2824}}. (These are also the decade diacritics, at left in the table below, of the second and third decade.)\n\nIn addition, there are ten patterns that are based on the first two letters ({{bc|a|b}}) with their dots shifted to the right; these were assigned to non-French letters (''\u00ec \u00e4 \u00f2'' {{Braille cell|type=text|\u280c|\u281c|\u282c}}), or serve non-letter functions: {{Braille cell|type=text|\u2808}} (superscript; in English the accent mark), {{Braille cell|type=text|\u2818}} (currency prefix), {{Braille cell|type=text|\u2828}} (capital, in English the [[decimal point]]), {{Braille cell|type=text|\u283c}} ([[number sign]]), {{Braille cell|type=text|\u2838}} (emphasis mark), {{Braille cell|type=text|\u2810}} (symbol prefix).\n\n:{| class=wikitable\n|+ The 64 modern braille cells{{anchor|upper-half cells}}{{NoteTag|The characters have been arranged by decade, with decade diacritics listed at left, and supplementary characters included on the right according to their diacritic. See [[1829 braille]], where the 12 characters listed in the first line are used for shorthand and are found in this order for the 12 notes of plainsong notation, and [[French Braille]], where the 'final' form of Braille's alphabet is laid out in the same way. However, modern tables often organize the supplementary characters differently: Those with a dot 3 are listed as a 6th group of 6 characters, and those with dots only on the right side are listed as a 7th group of 7, without anything in common with the other characters in the columns they are listed under.}}\n!colspan=2|decade|| ||colspan=10|numeric sequence || ||colspan=2|shift right\n|- align=center\n!1st\n|[[File:Braille NULL.svg|40px]] ||\n|[[File:Braille A1.svg|40px]]\n|[[File:Braille B2.svg|40px]]\n|[[File:Braille C3.svg|40px]]\n|[[File:Braille D4.svg|40px]]\n|[[File:Braille E5.svg|40px]]\n|[[File:Braille F6.svg|40px]]\n|[[File:Braille G7.svg|40px]]\n|[[File:Braille H8.svg|40px]]\n|[[File:Braille I9.svg|40px]]\n|[[File:Braille J0.svg|40px]] ||\n|[[File:Braille Accent.svg|40px]]\n|[[File:Braille Currency.svg|40px]]\n|- align=center\n!2nd\n|[[File:Braille Apostrophe colored.svg|40px|' (Apostrophe)]] ||\n|[[File:Braille K colored.svg|40px]]\n|[[File:Braille L colored.svg|40px]]\n|[[File:Braille M colored.svg|40px]]\n|[[File:Braille N colored.svg|40px]]\n|[[File:Braille O colored.svg|40px]]\n|[[File:Braille P colored.svg|40px]]\n|[[File:Braille Q colored.svg|40px]]\n|[[File:Braille R colored.svg|40px]]\n|[[File:Braille S colored.svg|40px]]\n|[[File:Braille T colored.svg|40px]] ||\n|[[File:Braille ST colored.svg|40px]]\n|[[File:Braille \u00c4 colored.svg|40px]]\n|- align=center\n!3rd\n|[[File:Braille Hyphen colored.svg|40px|- (Hyphen)]] ||\n|[[File:Braille U colored.svg|40px]]\n|[[File:Braille V colored.svg|40px]]\n|[[File:Braille X colored.svg|40px]]\n|[[File:Braille Y colored.svg|40px]]\n|[[File:Braille Z colored.svg|40px]]\n|[[File:Braille \u00c7 colored.svg|40px]]\n|[[File:Braille \u00c9 colored.svg|40px]]\n|[[File:Braille \u00c0 colored.svg|40px]]\n|[[File:Braille \u00c8 colored.svg|40px]]\n|[[File:Braille \u00d9 colored.svg|40px]] ||\n|[[File:Braille \u00d2 colored.svg|40px]]\n|[[File:Braille Number colored.svg|40px|# (Number)]]\n|- align=center\n!4th\n|[[File:Braille Capital colored.svg|40px|UPPERCASE (Capital)]] ||\n|[[File:Braille \u00c2 colored.svg|40px]]\n|[[File:Braille \u00ca colored.svg|40px]]\n|[[File:Braille \u00ce colored.svg|40px]]\n|[[File:Braille \u00d4 colored.svg|40px]]\n|[[File:Braille \u00db colored.svg|40px]]\n|[[File:Braille \u00cb colored.svg|40px]]\n|[[File:Braille \u00cf colored.svg|40px]]\n|[[File:Braille \u00dc colored.svg|40px]]\n|[[File:Braille \u00d6 colored.svg|40px]]\n|[[File:Braille W colored.svg|40px]] ||\n|[[File:Braille Decimal colored.svg|40px|. (Decimal Point)]]\n|[[File:Braille Cursive colored.svg|40px]]\n|- align=center\n!5th\n! <span style="color:#006060">shift<br />down</span>\n|\n|[[File:Braille Comma colored.svg|40px|, (Comma)]]\n|[[File:Braille Semicolon colored.svg|40px|; (Semicolon)]]\n|[[File:Braille Colon colored.svg|40px|: (Colon)]]\n|[[File:Braille Period colored.svg|40px|. (Period)]]\n|[[File:Braille QuestionMark colored.svg|40px|? (Question Mark)]]\n|[[File:Braille ExclamationPoint colored.svg|40px|! (Exclamation Point)]]\n|[[File:Braille Bracket colored.svg|40px]]\n|[[File:Braille QuoteOpen colored.svg|40px|\u201c (Quote Open)]]\n|[[File:Braille Asterisk colored.svg|40px|* (Asterisk)]]\n|[[File:Braille QuoteClose colored.svg|40px|\u201d (Quote Close)]] ||\n|[[File:Braille ContractionPrefix colored.svg|40px]]\n|[[File:Braille Correction colored.svg|40px]]\n|}\n\nThe first four decades are similar in respect that in those decades the decade dots are applied to the numeric sequence as a logical "inclusive OR" operation whereas the fifth decade applies a "shift down" operation to the numeric sequence.\n\nOriginally there had been nine decades. The fifth through ninth used dashes as well as dots, but proved to be impractical and were soon abandoned. These could be replaced with what we now know as the number sign ({{Braille cell|type=text|\u283c}}), though that only caught on for the digits (old 5th decade \u2192 modern 1st decade). The dash occupying the top row of the original sixth decade was simply dropped, producing the modern fifth decade. (See [[1829 braille]].)\n\n Historically, there have been three principles in assigning the values of a [[Linear writing|linear script]] (print) to Braille:  Using Louis Braille's original French letter values; reassigning the braille letters according to the [[sort order]] of the print alphabet being transcribed; and reassigning the letters to improve the efficiency of writing in braille.\n\nUnder international consensus, most braille alphabets follow the French sorting order for the 26 letters of the [[ISO basic Latin alphabet|basic Latin alphabet]], and there have been attempts at unifying the letters beyond these 26 (see [[international braille]]), though differences remain, for example in [[German Braille]]. This unification avoids the chaos of each nation reordering the braille code to match the sorting order of its print alphabet, as happened in [[Algerian Braille]], where braille codes were numerically reassigned to match the order of the Arabic alphabet and bear little relation to the values used in other countries (compare modern [[Arabic Braille]], which uses the French sorting order), and as happened in an early American version of English Braille, where the letters ''w, x, y, z'' were reassigned to match English alphabetical order.  A convention sometimes seen for letters beyond the basic 26 is to exploit the physical symmetry of braille patterns iconically, for example, by assigning a reversed ''n'' to ''\u00f1'' or an inverted ''s'' to ''sh''. (See [[Hungarian Braille]] and [[Bharati Braille]], which do this to some extent.)\n\nA third principle was to assign braille codes according to frequency, with the simplest patterns (quickest ones to write with a stylus) assigned to the most frequent letters of the alphabet. Such frequency-based alphabets were used in Germany and the United States in the 19th century (see [[American Braille]]), but with the invention of the braille typewriter their advantage disappeared, and none are attested in modern use \u2013 they had the disadvantage that the resulting small number of dots in a text interfered with following the alignment of the letters, and consequently made texts more difficult to read than Braille's more arbitrary letter-assignment. Finally, there are braille scripts which don't order the codes numerically at all, such as [[Japanese Braille]] and [[Korean Braille]], which are based on more abstract principles of syllable composition.\n\nTexts are sometimes written in a script of eight dots per cell rather than six, enabling them to encode a greater number of symbols. (See [[Gardner\u2013Salinas braille codes]].) [[Luxembourgish Braille]] has adopted eight-dot cells for general use; for example, it adds a dot below each letter to derive its capital variant."}},
{"article_title": "Biochemistry", "pageid": "3954", "revid": "1060508743", "timestamp": "2021-12-15T23:59:10Z", "history_paths": [["Biochemistry --- Introduction ---", "History"]], "categories": ["biochemistry", "biotechnology", "molecular biology", "genomics"], "heading_tree": {"Biochemistry --- Introduction ---": {"History": {}, "Starting materials: the chemical elements of life": {}, "Biomolecules": {"Carbohydrates": {}, "Lipids": {}, "Proteins": {}, "Nucleic acids": {}}, "Metabolism": {"Carbohydrates as energy source": {"Glycolysis (anaerobic)": {}, "Aerobic": {}, "Gluconeogenesis": {}}}, "Relationship to other \"molecular-scale\" biological sciences": {}, "See also": {"Lists": {}, "See also": {}}, "Notes": {}, "References": {"Cited literature": {}}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Biochemistry --- Introduction ---|History": "{{Main| History of biochemistry}}\n[[File:Gerty Theresa Radnitz Cori (1896-1957) and Carl Ferdinand Cori - restoration1.jpg|thumb|upright|[[Gerty Cori]] and [[Carl Cori]] jointly won the [[Nobel Prize in Physiology or Medicine|Nobel Prize]] in 1947 for their discovery of  the [[Cori cycle]] at RPMI.]]\n\nAt its most comprehensive definition, biochemistry can be seen as a study of the components and composition of living things and how they come together to become life. In this sense, the history of biochemistry may therefore go back as far as the [[Ancient Greece|ancient Greeks]].<ref name="history of science">[[#Helvoort|Helvoort]] (2000), p. 81.</ref> However, biochemistry as a specific [[scientific discipline]] began sometime in the 19th century, or a little earlier, depending on which aspect of biochemistry is being focused on. Some argued that the beginning of biochemistry may have been the discovery of the first [[enzyme]], [[diastase]] (now called [[amylase]]), in 1833 by [[Anselme Payen]],<ref>[[#Hunter|Hunter]] (2000), p. 75.</ref> while others considered [[Eduard Buchner]]'s first demonstration of a complex biochemical process [[Ethanol fermentation|alcoholic fermentation]] in cell-free extracts in 1897 to be the birth of biochemistry.<ref name=":0">{{Cite journal|last=Srinivasan|first=Bharath|date=2020-09-27|title=Words of advice: teaching enzyme kinetics|journal=The FEBS Journal|volume=288|issue=7|pages=2068\u20132083|doi=10.1111/febs.15537|pmid=32981225|issn=1742-464X|doi-access=free}}</ref><ref>[[#Hamblin|Hamblin]] (2005), p. 26.</ref><ref>[[#Hunter|Hunter]] (2000), pp. 96\u201398.</ref>  Some might also point as its beginning to the influential 1842 work by [[Justus von Liebig]], ''Animal chemistry, or, Organic chemistry in its applications to physiology and pathology'', which presented a chemical theory of metabolism,<ref name="history of science" /> or even earlier to the 18th century studies on [[fermentation]] and [[Cellular respiration|respiration]] by [[Antoine Lavoisier]].<ref>[[#Berg|Berg]] (1980), pp. 1\u20132.</ref><ref>[[#Holmes|Holmes]] (1987), p. xv.</ref> Many other pioneers in the field who helped to uncover the layers of complexity of biochemistry have been proclaimed founders of modern biochemistry. [[Hermann Emil Fischer|Emil Fischer]], who studied the chemistry of proteins,<ref>[[#Feldman|Feldman]] (2001), p. 206.</ref> and [[Frederick Gowland Hopkins|F. Gowland Hopkins]], who studied enzymes and the dynamic nature of biochemistry, represent two examples of early biochemists.<ref>[[#Rayner|Rayner-Canham]] (2005), p. 136.</ref>\n\nThe term "biochemistry" itself  is derived from a combination of [[biology]] and [[chemistry]]. In 1877, [[Felix Hoppe-Seyler]] used the term (''biochemie'' in German) as a synonym for [[physiological chemistry]] in the foreword to the first issue of ''[[Zeitschrift f\u00fcr Physiologische Chemie]]'' (Journal of Physiological Chemistry) where he argued for the setting up of institutes dedicated to this field of study.<ref>[[#Ziesak|Ziesak]] (1999), p. 169.</ref><ref>[[#Kleinkauf|Kleinkauf]] (1988), p. 116.</ref> The German [[chemist]] [[Carl Neuberg]] however is often cited to have coined the word in 1903,<ref name="Ben-Menahem 2009">[[#Ben|Ben-Menahem]] (2009), p. 2982.</ref><ref>[[#Amsler|Amsler]] (1986), p. 55.</ref><ref>[[#Horton|Horton]] (2013), p. 36.</ref> while some credited it to [[Franz Hofmeister]].<ref>[[#Kleinkauf|Kleinkauf]] (1988), p. 43.</ref>\n\n[[File:DNA orbit animated.gif|thumb|left|upright|DNA structure ({{PDB2|1D65}})<ref>[[#Edwards|Edwards]] (1992), pp. 1161\u20131173.</ref>]]\nIt was once generally believed that life and its materials had some essential property or substance (often referred to as the "[[vital principle]]") distinct from any found in non-living matter, and it was thought that only living beings could produce the molecules of life.<ref>[[#Fiske|Fiske]] (1890), pp. 419\u201320.</ref> In 1828, [[Friedrich W\u00f6hler]] published a paper on his serendipitous [[urea]] [[W\u00f6hler synthesis|synthesis]] from potassium cyanate and ammonium sulfate; some regarded that as a direct overthrow of vitalism and the establishment of organic chemistry.<ref>{{Cite journal|last=W\u00f6hler|first=F.|date=1828|title=Ueber k\u00fcnstliche Bildung des Harnstoffs|url=http://dx.doi.org/10.1002/andp.18280880206|journal=Annalen der Physik und Chemie|volume=88|issue=2|pages=253\u2013256|doi=10.1002/andp.18280880206|bibcode=1828AnP....88..253W|issn=0003-3804}}</ref> <ref name="Kauffman 20012">[[#Kauffman|Kauffman]] (2001), pp. 121\u2013133.</ref>  However, the W\u00f6hler synthesis has sparked controversy as some reject the death of vitalism at his hands.<ref>{{Cite journal|last=Lipman|first=Timothy O.|date=August 1964|title=Wohler's preparation of urea and the fate of vitalism|url=http://dx.doi.org/10.1021/ed041p452|journal=Journal of Chemical Education|volume=41|issue=8|pages=452|doi=10.1021/ed041p452|bibcode=1964JChEd..41..452L|issn=0021-9584}}</ref>  Since then, biochemistry has advanced, especially since the mid-20th century, with the development of new techniques such as [[chromatography]], [[X-ray diffraction]], [[dual polarisation interferometry]], [[protein nuclear magnetic resonance spectroscopy|NMR spectroscopy]], [[radioisotopic labeling]], [[electron microscope|electron microscopy]] and [[molecular dynamics]] simulations. These techniques allowed for the discovery and detailed analysis of many molecules and [[metabolic pathway]]s of the [[cell (biology)|cell]], such as [[glycolysis]] and the [[Krebs cycle]] (citric acid cycle), and led to an understanding of biochemistry on a molecular level.\n\nAnother significant historic event in biochemistry is the discovery of the [[gene]], and its role in the transfer of information in the cell. In the 1950s, [[James D. Watson]], [[Francis Crick]], [[Rosalind Franklin]] and [[Maurice Wilkins]] were instrumental in solving DNA structure and suggesting its relationship with the genetic transfer of information.<ref>[[#Tropp|Tropp]] (2012), pp. 19\u201320.</ref> In 1958, [[George Beadle]] and [[Edward Tatum]] received the [[Nobel Prize]] for work in fungi showing that [[one gene-one enzyme hypothesis|one gene produces one enzyme]].<ref name="Krebs 2012">[[#Krebs|Krebs]] (2012), p. 32.</ref> In 1988, [[Colin Pitchfork]] was the first person convicted of murder with [[DNA]] evidence, which led to the growth of [[forensic science]].<ref name="Butler 2009">[[#Butler|Butler]] (2009), p. 5.</ref> More recently, [[Andrew Z. Fire]] and [[Craig C. Mello]] received the [[Nobel Prize in Physiology or Medicine|2006 Nobel Prize]] for discovering the role of [[RNA interference]] ([[RNAi]]), in the silencing of [[gene expression]].<ref name="Sen 2007">[[#Chandan|Chandan]] (2007), pp. 193\u2013194.</ref>"}},
{"article_title": "Bicycle", "pageid": "3973", "revid": "1062365957", "timestamp": "2021-12-28T01:30:54Z", "history_paths": [["Bicycle --- Introduction ---", "History"], ["Bicycle --- Introduction ---", "Social and historical aspects"]], "categories": ["bicycles", "cycle types", "19th-century inventions", "appropriate technology", "articles containing video clips", "sustainable technologies", "sustainable transport", "german inventions"], "heading_tree": {"Bicycle --- Introduction ---": {"Etymology": {}, "History": {}, "Uses": {}, "Technical aspects": {"Types": {}, "Dynamics": {}, "Performance": {}}, "Parts": {"Frame": {}, "Drivetrain and gearing": {}, "Steering": {}, "Seating": {}, "Brakes": {}, "Suspension": {}, "Wheels and tires": {}, "Groupset": {}, "Accessories": {}, "Standards": {}}, "Maintenance and repair": {"Maintenance": {}, "Repair": {}, "Tools": {}}, "Social and historical aspects": {"In daily life": {}, "Poverty alleviation": {}, "Female emancipation": {}, "Economic implications": {}, "Environmental impact": {}, "Religious implications": {}, "Manufacturing": {}, "Legal requirements": {}, "Theft": {}}, "See also": {}, "Citations": {}, "General sources": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Bicycle --- Introduction ---|History": "{{Main|History of the bicycle}}\n{{Refimprove section|date=June 2021}} \n[[File:Draisine or Laufmaschine, around 1820. Archetype of the Bicycle. Pic 01.jpg|thumb|Wooden ''[[Dandy horse|draisine]]'' (around 1820), the first two-wheeler and as such the archetype of the bicycle]]\n\nThe "[[dandy horse]]", also called Draisienne or Laufmaschine, was the first human means of transport to use only two wheels in [[tandem]] and was invented by the German [[Freiherr|Baron]] [[Karl Drais|Karl von Drais]]. It is regarded as the first bicycle, but it did not have pedals;<ref>{{Cite web|url=https://www.irishtimes.com/culture/heritage/world-s-first-bicycle-ride-took-place-200-years-ago-1.3112354|title=World's first bicycle ride took place 200 years ago|last=Scally|first=Derek|date=10 June 2017|website=The Irish Times|language=en|access-date=29 March 2020}}</ref><ref>{{Cite web|url=http://www.exploratorium.edu/cycling/frames1.html|title=Frames & Materials|website=Science of Cycling|access-date=29 March 2020}}</ref><ref>{{Cite web|url=https://www.bikecitizens.net/200th-anniversary-bicycle-changed-society/|title=200th anniversary: How the bicycle changed society|last=Gliemann|first=Jennifer|date=21 March 2017|website=Bike Citizens|language=en-US|access-date=29 March 2020}}</ref><ref>{{Cite book|last1=Limebeer|first1=D. J. N.|title=Dynamics and Optimal Control of Road Vehicles|last2=Massaro|first2=Matteo|publisher=Oxford University Press|year=2018|isbn=9780192559814|pages=13\u201315}}</ref> Drais introduced it to the public in [[Mannheim]] in 1817 and in Paris in 1818.<ref name=csts>{{cite web |publisher=Canada Science and Technology Museum |title=Baron von Drais' Bicycle |url=http://www.sciencetech.technomuses.ca/english/collection/cycles2.cfm |access-date=10 February 2014 |archive-url=https://web.archive.org/web/20061229213036/http://www.sciencetech.technomuses.ca/english/collection/cycles2.cfm |archive-date=29 December 2006 |url-status=dead }}</ref>{{sfn|Herlihy|2004|p=26}} Its rider sat astride a wooden frame supported by two in-line wheels and pushed the vehicle along with his or her feet while steering the front wheel.<ref name=csts/>\n\n[[File:Michauxjun.jpg|thumb|upright=0.9|left|Michaux's son on a velocipede 1868]]\n\nThe first mechanically-propelled, two-wheeled vehicle may have been built by [[Kirkpatrick MacMillan]], a Scottish blacksmith, in 1839, although the claim is often disputed.{{sfn|Herlihy|2004|pp=66\u201367}} He is also associated with the first recorded instance of a cycling traffic offense, when a Glasgow newspaper in 1842 reported an accident in which an anonymous "gentleman from Dumfries-shire... bestride a velocipede... of ingenious design" knocked over a little girl in Glasgow and was fined five [[shilling]]s.<ref>{{cite news |url=https://www.bbc.co.uk/news/magazine-13040607 |title=Is dangerous cycling a problem? |publisher=[[BBC News]] |date=13 April 2011 |access-date=11 February 2014}}</ref>\n\nIn the early 1860s, Frenchmen [[Pierre Michaux]] and [[Pierre Lallement]] took bicycle design in a new direction by adding a mechanical [[Crank (mechanism)|crank]] drive with pedals on an enlarged front wheel (the [[velocipede]]). This was the first in mass production. Another French inventor named Douglas Grasso had a failed prototype of Pierre Lallement's bicycle several years earlier. Several inventions followed using rear-wheel drive, the best known being the rod-driven velocipede by Scotsman [[Thomas McCall (inventor)|Thomas McCall]] in 1869. In that same year, bicycle wheels with wire spokes were patented by [[Eug\u00e8ne Meyer (inventor)|Eug\u00e8ne Meyer]] of Paris.<ref>''Bulletin des lois de la R\u00e9publique fran\u00e7aise'' (1873) 12th series, vol. 6, [https://books.google.com/books?id=8S0UAAAAYAAJ&pg=PA648#v=onepage&q&f=false p. 648, patent no. 86,705: "Perfectionnements dans les roues de v\u00e9locip\u00e8des"] ("Improvements in the wheels of bicycles"), issued 4 August 1869.</ref> The French ''v\u00e9locip\u00e8de'', made of iron and wood, developed into the "[[penny-farthing]]" (historically known as an "ordinary bicycle", a [[retronym]], since there was then no other kind).{{sfn|Norcliffe|2001|p=50}} It featured a tubular steel frame on which were mounted wire-spoked wheels with solid rubber tires. These bicycles were difficult to ride due to their high seat and poor [[weight distribution]]. In 1868 Rowley Turner, a sales agent of the Coventry Sewing Machine Company (which soon became the [[Hillman#History|Coventry Machinists Company]]), brought a Michaux cycle to [[Coventry]], England. His uncle, Josiah Turner, and business partner [[James Starley]], used this as a basis for the 'Coventry Model' in what became Britain's first cycle factory.<ref>McGrory, David. ''A History of Coventry'' (Chichester: Phillimore, 2003), p. 221.</ref>\n\n[[File:1886 Starley 'Rover' Safety Cycle British Motor Museum 09-2016 (29928044262).jpg|thumb|1886 [[Rover Company#Before cars|Rover]] [[safety bicycle]] at the [[British Motor Museum]]. The first modern bicycle, it featured a rear-wheel-drive, [[chain-drive]]n cycle with two similar-sized wheels. Dunlop's [[Bicycle tire|pneumatic tire]] was added to the bicycle in 1888.]]\n\nThe ''dwarf ordinary'' addressed some of these faults by reducing the front wheel [[diameter]] and setting the [[bicycle seat|seat]] further back. This, in turn, required gearing\u2014effected in a variety of ways\u2014to efficiently use pedal power. Having to both pedal and steer via the front wheel remained a problem. Englishman [[John Kemp Starley|J.K. Starley]] (nephew of James Starley), J.H. Lawson, and Shergold solved this problem by introducing the [[chain drive]] (originated by the unsuccessful "bicyclette" of Englishman Henry Lawson),{{sfn|Norcliffe|2001|p=47}} connecting the frame-mounted cranks to the rear wheel. These models were known as [[safety bicycle]]s, dwarf safeties, or upright bicycles for their lower seat height and better weight distribution, although without pneumatic tires the ride of the smaller-wheeled bicycle would be much rougher than that of the larger-wheeled variety. Starley's 1885 [[Rover Company|Rover]], manufactured in Coventry<ref>McGrory, p. 222.</ref> is usually described as the first recognizably modern bicycle.<ref>{{cite news|title=Cycle market: Moving into the fast lane|url=https://www.independent.co.uk/news/business/analysis-and-features/cycle-market-moving-into-the-fast-lane-1702191.html |work=[[The Independent]] |location=London |date=26 February 2018}}</ref> Soon the ''seat tube'' was added, creating the modern bike's double-triangle ''diamond frame''.\n\n[[File:John Boyd Dunlop (c1915).jpg|thumb|upright|left|[[John Boyd Dunlop]] on a bicycle c. 1915]]\n\nFurther innovations increased comfort and ushered in a second [[bicycle craze]], the 1890s ''Golden Age of Bicycles''. In 1888, Scotsman [[John Boyd Dunlop]] introduced the first practical pneumatic tire, which soon became universal. [[Willie Hume]] demonstrated the supremacy of Dunlop's tyres in 1889, winning the tyre's first-ever races in Ireland and then England.<ref name="Gold Hume">Hume, William (1938). [http://www.thepedalclub.org/archives/goldenbook/u-z/WilliamHume.html ''The Golden Book of Cycling'']. Archive maintained by 'The Pedal Club'. {{webarchive|url=https://web.archive.org/web/20120403120845/http://www.thepedalclub.org/archives/goldenbook/u-z/WilliamHume.html |date=3 April 2012 }}</ref><ref name="Dunlop time">[http://www.dunlop.eu/dunlop_uk/what_sets_dunlop_apart/history/ Dunlop, What sets Dunlop apart, History, 1889]</ref> Soon after, the rear [[freewheel]] was developed, enabling the rider to coast. This refinement led to the 1890s invention<ref>{{cite web\n| url = http://www.sheldonbrown.com/coaster-brakes.html\n| title = One-Speed Bicycle Coaster Brakes\n| first = Sheldon | last = Brown\n| quote = Coaster brakes were invented in the 1890s.\n| access-date = 1 December 2010| archive-url= https://web.archive.org/web/20101129160301/http://sheldonbrown.com/coaster-brakes.html| archive-date= 29 November 2010 | url-status= live}}</ref> of [[coaster brake]]s. [[Derailleur gears|D\u00e9railleur gears]] and hand-operated [[Bowden cable]]-pull brakes were also developed during these years, but were only slowly adopted by casual riders.\n\nThe [[Svea Velocipede]] with vertical pedal arrangement and [[locking hubs]] was introduced in 1892 by the Swedish engineers [[Fredrik Ljungstr\u00f6m]] and [[Birger Ljungstr\u00f6m]]. It attracted attention at the [[World Fair]] and was produced in a few thousand units.\n\n[[File:Old CTC sign.jpg|thumb|[[Cycling UK|Cyclists' Touring Club]] sign on display at the [[National Museum of Scotland]]]]\n\nIn the 1870s many [[cycling club]]s flourished. They were popular in a time when there were not cars on the market and the principal mode of transportation was [[horse-drawn vehicle]]s, such the [[horse and buggy]] or the [[horsecar]]. Among the earliest clubs was [[Cycling UK|The Bicycle Touring Club]], which has operated since 1878. By the turn of the century, cycling clubs flourished on both sides of the Atlantic, and touring and racing became widely popular. The [[Raleigh Bicycle Company]] was founded in Nottingham, England in 1888. It became the biggest bicycle manufacturing company in the world, making over two million bikes per year.<ref>{{cite news|title=On Your Bike...|url=https://www.bbc.co.uk/insideout/eastmidlands/series2/raleigh_bikes_cycling.shtml|agency=BBC|date=26 February 2018}}</ref>\n\nBicycles and horse buggies were the two mainstays of private transportation just prior to the automobile, and the grading of smooth roads in the late 19th century was stimulated by the widespread advertising, production, and use of these devices.{{sfn|Herlihy|2004|p=280}} More than 1 billion bicycles have been manufactured worldwide as of the early 21st century.<ref name=Koeppel2007/><ref name=Economist2011/><ref name=worldmeters/> Bicycles are the most common vehicle of any kind in the world, and the most numerous model of any kind of vehicle, whether human-powered or [[motor vehicle]], is the Chinese [[Flying Pigeon]], with numbers exceeding 500 million.<ref name=Koeppel2007/> The next most numerous vehicle, the [[Honda Super Cub]] motorcycle, has more than 100 million units made,<ref name="SuperCub">{{cite web |url=https://www.honda.co.jp/supercub-anniv/ |title=Honda\uff5cSUPER CUB FANSITE\uff5c\u30b9\u30fc\u30d1\u30fc\u30ab\u30d6\u30d5\u30a1\u30f3\u306e\u305f\u3081\u306e\u30dd\u30fc\u30bf\u30eb\u30b5\u30a4\u30c8 |accessdate= May 20, 2021}}</ref> while most produced car, the [[Toyota Corolla]], has reached 44 million and counting.<ref name=Squatriglia2008/><ref name=AMA2006/><ref name=ABC/><ref name=FoxBusiness/>\n\n<gallery widths="200px" heights="200px">\nFile:Women on bicycles, late 19th Century USA.jpg|Women on bicycles on unpaved road, USA, late 19th century\nFile:Ordinary bicycle01.jpg|A ''[[penny-farthing]]'' or ''ordinary bicycle'' photographed in the [[\u0160koda Auto]] museum in the Czech Republic\nFile:Svea Velocipede.jpg|The [[Svea Velocipede]] by [[Fredrik Ljungstr\u00f6m]] and [[Birger Ljungstr\u00f6m]], exhibited at the [[Swedish National Museum of Science and Technology]]\nFile:BicyclePlymouth.jpg|Bicycle in [[Plymouth, England|Plymouth]], England at the start of the 20th century\nFile:I0002502.tif|Man with a bicycle in Glengarry County, Ontario [between 1895 and 1910\nFile:The first bicycle.png|The first bicycle\nFile:The London Hansom Cycle 1896.png|Drawing from an 1896 newspaper of The London Hansom Cycle]\n</gallery>", "Bicycle --- Introduction ---|Social and historical aspects": "{{Unreferenced section|date=June 2021}}\nThe bicycle has had a considerable effect on human society, in both the cultural and industrial realms.\n\n Around the turn of the 20th century, bicycles reduced crowding in inner-city tenements by allowing workers to commute from more spacious dwellings in the suburbs. They also reduced dependence on horses. Bicycles allowed people to travel for leisure into the country, since bicycles were three times as energy efficient as walking and three to four times as fast.\n\nIn built-up cities around the world, [[urban planning]] uses [[cycling infrastructure]] like bikeways to reduce [[traffic congestion]] and air pollution.<ref>{{cite journal | pmc = 3005092 | pmid=21174189 | doi=10.1007/s11524-010-9509-6 | volume=87 | issue=6 | title=Built environment influences on healthy transportation choices: bicycling versus driving | year=2010 | journal=J Urban Health | pages=969\u201393 | last1 = Winters | first1 = M | last2 = Brauer | first2 = M | last3 = Setton | first3 = EM | last4 = Teschke | first4 = K}}</ref> A number of cities around the world have implemented schemes known as [[bicycle sharing system]]s or community bicycle programs.<ref>{{cite journal |last1=Shaheen |first1=Susan |last2=Guzman |first2=Stacey |last3=Zhang |first3=Hua |title=Bikesharing in Europe, the Americas, and Asia |journal=Transportation Research Record |volume=2143 |year=2010 |pages=159\u201367 |doi=10.3141/2143-20|s2cid=40770008 }}</ref><ref>{{cite journal|last=Shaheen |first=Stacey |author2=Stacey Guzman |title=Worldwide Bikesharing |journal=Access Magazine |year=2011 |url=http://uctc.net/access/39/access39_bikesharing.shtml |url-status=dead |archive-url=https://web.archive.org/web/20120326063609/http://www.uctc.net/access/39/access39_bikesharing.shtml |archive-date=26 March 2012 }}</ref> The first of these was the White Bicycle plan in [[Amsterdam]] in 1965. It was followed by yellow bicycles in [[La Rochelle]] and green bicycles in Cambridge. These initiatives complement public transport systems and offer an alternative to motorized traffic to help reduce congestion and pollution.<ref>{{cite journal |last1=Shaheen |first1=Susan |last2=Zhang |first2=Hua |last3=Martin |first3=Elliot |last4=Guzman |first4=Stacey |title=China's Hangzhou Public Bicycle |journal=Transportation Research Record |volume=2247 |year=2011 |pages=33\u201341 |doi=10.3141/2247-05|s2cid=111120290 |url=https://escholarship.org/content/qt62d8f2g3/qt62d8f2g3.pdf?t=psbd9f }}</ref> In Europe, especially in the Netherlands and parts of Germany and Denmark, bicycle commuting is common. In Copenhagen, a cyclists' organization runs a Cycling Embassy that promotes biking for commuting and sightseeing. The United Kingdom has a tax break scheme (IR 176) that allows employees to buy a new bicycle tax free to use for commuting.<ref>{{cite web|url=http://www.cyclescheme.co.uk/|title=Tax free bikes for work through the Government's Green Transport Initiative |publisher=Cyclescheme}}{{psc|date=September 2015}}</ref>\n\nIn the [[Netherlands]] all train stations offer free [[bicycle parking]], or a more secure parking place for a small fee, with the larger stations also offering bicycle repair shops. Cycling is so popular that the parking capacity may be exceeded, while in some places such as Delft the capacity is usually exceeded.<ref>{{cite news\n| url = http://www.nrc.nl/international/article2482297.ece/So_many_bikes%2C_so_little_space\n| title = So many bikes, so little space\n| first1 = Joel | last1 = Broekaert\n| first2 = Reinier | last2 = Kist\n| name-list-style = amp\n| date = 12 February 2010\n| newspaper = NRC Handelsblad\n| access-date = 13 February 2010\n| archive-url = https://web.archive.org/web/20100213211227/http://www.nrc.nl/international/article2482297.ece/So_many_bikes%2C_so_little_space\n| archive-date = 13 February 2010\n| url-status = dead\n}}</ref> In [[Trondheim]] in Norway, the [[Trampe bicycle lift]] has been developed to encourage cyclists by giving assistance on a steep hill. Buses in many cities have [[bicycle carrier]]s mounted on the front.\n\nThere are towns in some countries where [[bicycle culture]] has been an integral part of the landscape for generations, even without much official support. That is the case of [[\u00cdlhavo Municipality|\u00cdlhavo]], in Portugal.\n\nIn cities where bicycles are not integrated into the public transportation system, commuters often use bicycles as elements of a [[mixed-mode commuting|mixed-mode commute]], where the bike is used to travel to and from train stations or other forms of rapid transit. Some students who commute several miles drive a car from home to a campus parking lot, then ride a bicycle to class. [[Folding bicycle]]s are useful in these scenarios, as they are less cumbersome when carried aboard. Los Angeles removed a small amount of seating on some trains to make more room for bicycles and wheel chairs.<ref>{{cite web\n| url = http://la.streetsblog.org/2008/10/16/metro-making-room-for-bikes-on-their-trains/\n| title = Metro Making Room for Bikes on Their Trains\n| author = Damien Newton\n| date = 16 October 2008\n| publisher = LA.StreetsBlog.Org\n| access-date = 12 February 2010}}</ref>\n[[File:Cyclists at red 2.jpg|left|thumb|Urban cyclists in [[Copenhagen]] in Denmark at a traffic light]]\n\nSome US companies, notably in the [[High tech#Technology sectors|tech sector]], are developing both innovative cycle designs and cycle-friendliness in the workplace. [[Foursquare (company)|Foursquare]], whose CEO [[Dennis Crowley]] "pedaled to pitch meetings ... [when he] was raising money from [[venture capitalists]]" on a two-wheeler, chose a new location for its New York headquarters "based on where biking would be easy". Parking in the office was also integral to HQ planning. Mitchell Moss, who runs the [[Rudin Center for Transportation Policy & Management]] at [[New York University]], said in 2012: "Biking has become the mode of choice for the educated high tech worker".<ref>Bernstein, Andrea, [https://web.archive.org/web/20120223233448/http://www.marketplace.org/topics/tech/transportation-nation/techies-cutting-edge-bike-commuting "Techies on the cutting edge... of bike commuting"], ''[[Marketplace (radio program)|Marketplace]]'', 22 February 2012. "Bernstein reports from the [http://transportationnation.org/ Transportation Nation] project at WNYC". Retrieved 22 February 2012.</ref>\n\nBicycles offer an important mode of transport in many developing countries. Until recently, bicycles have been a staple of everyday life throughout Asian countries. They are the most frequently used method of transport for commuting to work, school, shopping, and life in general. In Europe, bicycles are commonly used.<ref>{{cite news|url=https://www.npr.org/blogs/parallels/2013/10/24/240493422/in-most-every-european-country-bikes-are-outselling-cars|title=In Almost Every European Country, Bikes Are Outselling New Cars|date=24 October 2013|newspaper=NPR|last1=Calamur|first1=Krishnadev}}</ref> They also offer a degree of exercise to keep individuals healthy.<ref>{{cite book |url=https://archive.org/details/bicyclevehiclefo0000lowe |first=Marcia D. |last=Lowe |year=1989 |title=The Bicycle: Vehicle for a Small Planet |publisher=Worldwatch Institute |isbn=978-0-916468-91-0 |url-access=registration }}{{page needed|date=September 2015}}</ref>\n\nBicycles are also celebrated in the visual arts. An example of this is the [[Bicycle Film Festival]], a film festival hosted all around the world.\n\n [[File:Banana-bike.jpg|thumb|Men in Uganda using a bicycle to transport bananas]]{{Excerpt|Bicycle poverty reduction}}\n\n {{See also|Bicycling and feminism}}\n[[File:A wheel within a wheel page 56.jpg|thumb|upright| "Let go \u2013 but stand by"; [[Frances Willard (suffragist)|Frances Willard]] learning to ride a bicycle.<ref name=Willard1895/>]]\nThe safety bicycle gave women unprecedented mobility, contributing to [[Emancipation of women|their emancipation]] in Western nations. As bicycles became safer and cheaper, more women had access to the personal freedom that bicycles embodied, and so the bicycle came to symbolize the [[New Woman]] of the late 19th century, especially in Britain and the United States.{{sfn|Herlihy|2004|pp=266\u201371}}<ref name="Distillations">{{cite journal|last1=Roberts |first1=Jacob |title=Women's work |journal=Distillations |date=2017|volume=3|issue=1 |pages=6\u201311 |url=https://www.sciencehistory.org/distillations/magazine/womens-work|access-date=22 March 2018}}</ref> The [[Bike boom#1890s|bicycle craze in the 1890s]] also led to a movement for so-called [[Victorian dress reform|rational dress]], which helped liberate women from corsets and ankle-length skirts and other restrictive garments, substituting the then-shocking [[bloomers (clothing)|bloomers]].{{sfn|Herlihy|2004|pp=266\u201371}}\n\nThe bicycle was recognized by 19th-century feminists and [[suffragist]]s as a "freedom machine" for women. American [[Susan B. Anthony]] said in a ''[[New York World]]'' interview on 2 February 1896: "I think it has done more to emancipate woman than any one thing in the world. I rejoice every time I see a woman ride by on a wheel. It gives her a feeling of self-reliance and independence the moment she takes her seat; and away she goes, the picture of untrammelled womanhood."<ref name=HustedHarper1898/>{{rp|859}} In 1895 [[Frances Willard (suffragist)|Frances Willard]], the tightly laced president of the [[Woman's Christian Temperance Union]], wrote ''A Wheel Within a Wheel: How I Learned to Ride the Bicycle, with Some Reflections by the Way'', a 75-page illustrated memoir praising "Gladys", her bicycle, for its "gladdening effect" on her health and political optimism.<ref name=Willard1895/> Willard used a cycling metaphor to urge other suffragists to action.<ref name=Willard1895/>\n\nIn 1985, Georgena Terry started the first women-specific bicycle company. Her designs featured frame geometry and wheel sizes chosen to better fit women, with shorter top tubes and more suitable reach.<ref>{{Cite web |title=6 Questions for Women's Bicycling Pioneer Georgena Terry |url=https://velojoy.com/2012/07/04/6-questions-for-womens-bicycling-pioneer-georgena-terry/ |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20120825135522/https://velojoy.com/2012/07/04/6-questions-for-womens-bicycling-pioneer-georgena-terry/ |archive-date=25 August 2012 |publisher=Velojoy |date=4 July 2012 |access-date=14 July 2021}}</ref>\n\n [[File:Columbia Bicycles 1886 Advertisement.svg|left|thumb|upright|[[Columbia Bicycles]] advertisement from 1886]]\n\n[[Bicycle industry|Bicycle manufacturing]] proved to be a training ground for other industries and led to the development of advanced metalworking techniques, both for the frames themselves and for special components such as [[ball bearing]]s, [[washer (mechanical)|washers]], and sprockets. These techniques later enabled skilled metalworkers and mechanics to develop the components used in early automobiles and aircraft.\n\n[[Wright brothers|Wilbur and Orville Wright]], a pair of businessmen, ran the [[Wright Cycle Company]] which designed, manufactured and sold their bicycles during the [[bike boom]] of the 1890s.<ref name="WDL">{{cite web |url = http://www.wdl.org/en/item/11373/ |title = Wilbur Wright Working in the Bicycle Shop |website = [[World Digital Library]] |date = 1897 |access-date = 22 July 2013 }}</ref>\n\nThey also served to teach the industrial models later adopted, including mechanization and [[mass production]] (later copied and adopted by [[Ford Motor Company|Ford]] and [[General Motors]]),{{sfn|Norcliffe|2001|p=23}}{{sfn|Norcliffe|2001|p=106}}{{sfn|Norcliffe|2001|p=108}} vertical integration{{sfn|Norcliffe|2001|p=106}} (also later copied and adopted by Ford), aggressive advertising{{sfn|Norcliffe|2001|pp=142\u201347}} (as much as 10% of all advertising in U.S. periodicals in 1898 was by bicycle makers),{{sfn|Norcliffe|2001|p=145}} lobbying for better roads (which had the side benefit of acting as advertising, and of improving sales by providing more places to ride),{{sfn|Norcliffe|2001|p=108}} all first practiced by Pope.{{sfn|Norcliffe|2001|p=108}} In addition, bicycle makers adopted the annual model change{{sfn|Norcliffe|2001|p=23}}<ref>Babaian, Sharon. ''The Most Benevolent Machine: A Historical Assessment of Cycles in Canada'' (Ottawa: National Museum of Science and Technology, 1998), p. 97.</ref> (later derided as [[planned obsolescence]], and usually credited to General Motors), which proved very successful.<ref>Babaian, p. 98.</ref>\n\nEarly bicycles were an example of [[conspicuous consumption]], being adopted by the fashionable elites.{{sfn|Norcliffe|2001|p=8}}{{sfn|Norcliffe|2001|p=12}}{{sfn|Norcliffe|2001|p=14}}{{sfn|Norcliffe|2001|p=23}}{{sfn|Norcliffe|2001|pp=147\u201348}}{{sfn|Norcliffe|2001|pp=187\u201388}}{{sfn|Norcliffe|2001|p=208}}{{sfn|Norcliffe|2001|pp=243\u201345}} In addition, by serving as a platform for accessories, which could ultimately cost more than the bicycle itself, it paved the way for the likes of the [[Barbie doll]].{{sfn|Norcliffe|2001|p=23}}{{sfn|Norcliffe|2001|p=121}}{{sfn|Norcliffe|2001|p=123}}\n\nBicycles helped create, or enhance, new kinds of businesses, such as bicycle messengers,{{sfn|Norcliffe|2001|p=212}} traveling seamstresses,{{sfn|Norcliffe|2001|p=214}} riding academies,{{sfn|Norcliffe|2001|p=131}} and racing rinks.{{sfn|Norcliffe|2001|p=30}}{{sfn|Norcliffe|2001|p=131}} Their board tracks were later adapted to early [[motorcycle racing|motorcycle]] and [[automobile racing]]. There were a variety of new inventions, such as [[spoke]] tighteners,{{sfn|Norcliffe|2001|p=125}} and specialized lights,{{sfn|Norcliffe|2001|p=123}}{{sfn|Norcliffe|2001|p=125}} socks and shoes,{{sfn|Norcliffe|2001|pp=125\u201326}} and even cameras, such as the [[Eastman Kodak|Eastman Company]]'s Poco.{{sfn|Norcliffe|2001|p=238}} Probably the best known and most widely used of these inventions, adopted well beyond cycling, is Charles Bennett's Bike Web, which came to be called the [[jock strap]].{{sfn|Norcliffe|2001|p=128}}\n\n[[File:Person mit fahrrad feb07.jpg|thumb|upright|A man uses a bicycle to carry goods in [[Ouagadougou]], [[Burkina Faso]]]]\nThey also presaged a move away from public transit{{sfn|Norcliffe|2001|pp=214\u201315}} that would explode with the introduction of the automobile.\n\nJ. K. Starley's company became the Rover Cycle Company Ltd. in the late 1890s, and then simply the [[Rover Company]] when it started making cars. [[Morris Motors]] Limited (in [[Oxford]]) and [[\u0160koda Auto|\u0160koda]] also began in the bicycle business, as did the [[Wright brothers]].<ref>\n{{cite web\n| title = The Wrights' bicycle shop\n| year = 2007\n| url = http://www.nasm.si.edu/Wrightbrothers/who/1893/shop.cfm\n| access-date = 5 February 2007\n| archive-url = https://web.archive.org/web/20070125080218/http://www.nasm.si.edu/wrightbrothers/who/1893/shop.cfm\n| archive-date = 25 January 2007\n| url-status = dead\n}}</ref> Alistair Craig, whose company eventually emerged to become the engine manufacturers [[Ailsa Craig Engines|Ailsa Craig]], also started from manufacturing bicycles, in Glasgow in March 1885.\n\nIn general, U.S. and European cycle manufacturers used to assemble cycles from their own frames and components made by other companies, although very large companies (such as Raleigh) used to make almost every part of a bicycle (including bottom brackets, axles, etc.) In recent years, those bicycle makers have greatly changed their methods of production. Now, almost none of them produce their own frames.\n\nMany newer or smaller companies only design and market their products; the actual production is done by Asian companies. For example, some 60% of the world's bicycles are now being made in China. Despite this shift in production, as nations such as China and India become more wealthy, their own use of bicycles has declined due to the increasing affordability of cars and motorcycles.<ref>\n{{Cite news|author=Francois Bougo|date=26 May 2010|title=Beijing looks to revitalise bicycle culture|publisher=Agence France-Presse|url=https://www.google.com/hostednews/afp/article/ALeqM5iQeSSys_rKGJ7ve4u1ZsVyIA_LmQ|url-status=dead|archive-url=https://web.archive.org/web/20100531125628/https://www.google.com/hostednews/afp/article/ALeqM5iQeSSys_rKGJ7ve4u1ZsVyIA_LmQ|archive-date=31 May 2010}}</ref> One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the lower cost of labor in China.<ref>[[The Economist]], 15 February 2003</ref>\n\nIn line with the European financial crisis, in Italy in 2011 the number of bicycle sales (1.75 million) just passed the number of new car sales.<ref>{{cite news |url=https://www.bbc.co.uk/news/world-europe-19801599 |title=Italian bicycle sales 'surpass those of cars' |date=2 October 2012 |publisher=[[BBC News]]}}</ref>\n\n [[File:Utrecht - panoramio (2).jpg|thumb|Bicycles in [[Utrecht]], [[Netherlands]]]]\n\nOne of the profound economic implications of bicycle use is that it liberates the user from oil consumption. (Ballantine, 1972) The bicycle is an inexpensive, fast, healthy and environmentally friendly mode of transport. [[Ivan Illich]] stated that bicycle use extended the usable physical environment for people, while alternatives such as cars and motorways degraded and confined people's environment and mobility.<ref>Illich, I. (1974). ''Energy and equity''. New York, Harper & Row.</ref> Currently, two billion bicycles are in use around the world. Children, students, professionals, laborers, civil servants and seniors are pedaling around their communities. They all experience the freedom and the natural opportunity for exercise that the bicycle easily provides. Bicycle also has lowest carbon intensity of travel.<ref>[http://blogs.worldbank.org/publicsphere/global-cyclists-say-no-carbon-opt-cdm "Global cyclists say NO to carbon \u2013 opt for CDM"] {{Webarchive|url=https://web.archive.org/web/20171004035739/http://blogs.worldbank.org/publicsphere/global-cyclists-say-no-carbon-opt-cdm |date=4 October 2017 }}, The World Bank, 27 October 2015</ref>\n\n The proper [[Islamic bicycle]] for the Iranian women is a topic of heated discussion in both Sunni and Shia Islam.<ref>{{cite news|url=http://www.economist.com/node/21562945|title=Peddling religion: Why secular academics fret about an "Islamic bicycle"|date=15 September 2012|newspaper=The Economist}}</ref><ref>{{cite news|url=https://www.nytimes.com/2007/09/09/weekinreview/09slackman.html|title=Molding the Ideal Islamic Citizen|date=9 September 2007|author=Michael Slackman|newspaper=The New York Times}}</ref><ref>{{cite news|url=http://usatoday30.usatoday.com/news/opinion/2007-06-28-iranian-bicycle-women_N.htm|title='Islamic bicycle' can't slow Iranian women|author=Farzaneh Milani|date=28 June 2007|newspaper=USA Today}}</ref>\n\n {{See also|List of bicycle manufacturing companies}}\n\nThe global bicycle market is $61 billion in 2011.<ref>{{cite web|title=High Growth and Big Margins in the $61 Billion Bicycle Industry|url=http://seekingalpha.com/article/133109-high-growth-and-big-margins-in-the-61-billion-bicycle-industry|url-status=dead|archive-url=https://web.archive.org/web/20090428021811/http://seekingalpha.com/article/133109-high-growth-and-big-margins-in-the-61-billion-bicycle-industry|archive-date=28 April 2009|access-date=24 October 2011|publisher=Seeking Alpha}}</ref> {{As of|2009}} 130 million bicycles were sold every year globally and 66% of them were made in China.<ref>{{cite web|url=http://www.dare.co.in/opportunities/manufacturing/the-business-of-bicycles.htm |title=The Business of Bicycles | Manufacturing | Opportunities |publisher=DARE |date=1 June 2009 |access-date=24 October 2011 |url-status=dead |archive-url=https://web.archive.org/web/20111110153856/http://dare.co.in/opportunities/manufacturing/the-business-of-bicycles.htm |archive-date=10 November 2011 }}</ref>\n\n{| class="wikitable sortable"\n|+ EU28 Bicycle market 2000\u20132014<ref name=conebi2014/>\n|-\n! Year !! production (M) !! sales (M)\n|-\n| 2000 || 14.531 || 18.945\n|-\n| 2001 || 13.009 || 17.745\n|-\n| 2002 || 12.272 || 17.840\n|-\n| 2003 || 12.828 || 20.206\n|-\n| 2004 || 13.232 || 20.322\n|-\n| 2005 || 13.218 || 20.912\n|-\n| 2006 || 13.320 || 21.033\n|-\n| 2007 || 13.086 || 21.344\n|-\n| 2008 || 13.246 || 20.206\n|-\n| 2009 || 12.178 || 19.582\n|-\n| 2010 || 12.241 || 20.461\n|-\n| 2011 || 11.758 || 20.039\n|-\n| 2012 || 11.537 || 19.719\n|-\n| 2013 || 11.360 || 19.780\n|-\n| 2014 || 11.939 || 20.234\n|}\n\n{| class="wikitable sortable" style="text-align: right;"\n|+ EU28 Bicycle market 2014<ref name=conebi2014>{{cite web |url= http://www.conebi.eu/?wpdmdl=892 |title= 2014 European Bicycle Industry & Market Profile |publisher= Confederation of the European Bicycle Industry |date= 2015}}</ref>\n|-\n! Country !! Production (M) !! Parts !! Sales (M) !! Avg !! Sales (M\u20ac)\n|-\n| Italy || 2.729 || \u20ac491M || 1.696 || 288 || {{#expr:1.696*288round1}}\n|-\n| Germany || 2.139 || \u20ac286M || 4.100 || 528 || {{#expr:4.1*528round1}}\n|-\n| Poland || .991 || \u20ac58M || 1.094 || 380 || {{#expr:1.094*380round1}}\n|-\n| Bulgaria || .950 || \u20ac9M || .082 || 119 || {{#expr:.082*119round1}}\n|-\n| The Netherlands || .850 || \u20ac85M || 1.051 || 844 || {{#expr:1.051*844round1}}\n|-\n| Romania || .820 || \u20ac220M || .370 || 125 || {{#expr:.370*125round1}}\n|-\n| Portugal || .720 || \u20ac120M || .340 || 160 || {{#expr:.340*160round1}}\n|-\n| France || .630 || \u20ac170M || 2.978 || 307 || {{#expr:2.978*307round1}}\n|-\n| Hungary || .370 || \u20ac10M || .044 || 190 || {{#expr:.044*190round1}}\n|-\n| Spain || .356 || \u20ac10M || 1.089 || 451 || {{#expr:1.089*451round1}}\n|-\n| Czech Republic || .333 || \u20ac85M || .333 || 150 || {{#expr:.333*150round1}}\n|-\n| Lithuania || .323 || 0 || .050 || 110 || {{#expr:.050*110round1}}\n|-\n| Slovakia || .210 || \u20ac9M || .038 || 196 || {{#expr:.038*196round1}}\n|-\n| Austria || .138 || 0 || .401 || 450 || {{#expr:.401*450round1}}\n|-\n| Greece || .108 || 0 || .199 || 233 || {{#expr:.199*233round1}}\n|-\n| Belgium || .099 || \u20ac35M || .567 || 420 || {{#expr:.567*420round1}}\n|-\n| Sweden || .083 || 0 || .584 || 458 || {{#expr:.584*458round1}}\n|-\n| Great Britain || .052 || \u20ac34M || 3.630 || 345 || {{#expr:3.630*345round1}}\n|-\n| Finland || .034 || \u20ac32M || .300 || 320 || {{#expr:.300*320round1}}\n|-\n| Slovenia || .005 || \u20ac9M || .240 || 110 || {{#expr:.240*110round1}}\n|-\n| Croatia || 0 || 0 || .333 || 110 || {{#expr:.333*110round1}}\n|-\n| Cyprus || 0 || 0 || .033 || 110 || {{#expr:.033*110round1}}\n|-\n| Denmark || 0 || 0 || .470 || 450 || {{#expr:.470*450round1}}\n|-\n| Estonia || 0 || 0 || .062 || 190 || {{#expr:.062*190round1}}\n|-\n| Ireland || 0 || 0 || .091 || 190 || {{#expr:.091*190round1}}\n|-\n| Latvia || 0 || 0 || .040 || 110 || {{#expr:.040*110round1}}\n|-\n| Luxembourg || 0 || 0 || .010 || 450 || {{#expr:.010*450round1}}\n|-\n| Malta || 0 || 0 || .011 || 110 || {{#expr:.011*110round1}}\n|-\n! EU 28 !! 11.939 !! \u20ac1662M !! 20.234 || {{#expr:7941.2/20.234round0}} || 7941.2\n|}\n\n {{Main|Bicycle law}}\n\nEarly in its development, as with [[automobile]]s, there were restrictions on the operation of bicycles. Along with advertising, and to gain free publicity, [[Albert A. Pope]] litigated on behalf of cyclists.{{sfn|Norcliffe|2001|p=108}}\n\nThe 1968 [[Vienna Convention on Road Traffic]] of the United Nations considers a bicycle to be a vehicle, and a person controlling a bicycle (whether actually riding or not) is considered an operator. The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements before it can be used on public roads. In many [[jurisdiction]]s, it is an offense to use a bicycle that is not in a roadworthy condition.{{citation needed|date=September 2015}}\n\nIn most jurisdictions, bicycles must have functioning front and rear lights when ridden after dark. As some generator or [[dynamo]]-driven lamps operate only while moving, rear [[retroreflector|reflectors]] are frequently also mandatory. Since a moving bicycle makes little noise, some countries insist that bicycles have a warning bell for use when approaching pedestrians, equestrians, and other cyclists, though sometimes a [[car horn]] can be used when a 12 volt battery is available.{{citation needed|date=September 2015}}\n\nSome countries require child and/or adult cyclists to wear helmets, as this may protect riders from head trauma. Countries which require adult cyclists to wear helmets include Spain, [[Bicycle helmets in New Zealand|New Zealand]] and Australia. Mandatory helmet wearing is one of the most controversial topics in the cycling world, with proponents arguing that it reduces head injuries and thus is an acceptable requirement, while opponents argue that by making cycling seem more dangerous and cumbersome, it reduces cyclist numbers on the streets, creating an overall negative health effect (fewer people cycling for their own health, and the remaining cyclists being more exposed through a reversed [[safety in numbers]] effect).<ref>{{Cite news|date=5 April 2017|title=Want Safer Streets for Cyclists? Ditch the Helmet Laws.|language=en|work=Bloomberg.com|url=https://www.bloomberg.com/news/articles/2017-04-05/why-bike-helmet-laws-don-t-work|access-date=29 August 2020}}</ref>\n\n {{Main|Bicycle theft}}\n[[File:2008-09-06 Solitary bicycle wheel in a bike rack.jpg|thumb|upright|A bicycle wheel remains chained in a bike rack after the rest of the bicycle has been stolen at east campus of [[Duke University]] in [[Durham, North Carolina]].]]\n\nBicycles are popular targets for theft, due to their value and ease of resale.<ref>{{Cite journal|last1=Van Lierop|first1=Dea|last2=Grimsrud|first2=Michael|last3=El-Geneidy|first3=Ahmed|year=2014|title=Breaking into Bicycle Theft: Insights from Montreal, Canada|journal=International Journal of Sustainable Transportation|pages=490\u2013501}}</ref> The number of bicycles stolen annually is difficult to quantify as a large number of crimes are not reported.<ref>{{cite web |url=http://www.bicyclelaw.com/p.cfm/bicycle-safety/about-bike-theft |title=About Bicycle Theft |publisher=bicyclelaw.com |access-date=12 February 2014}}</ref> Around 50% of the participants in the Montreal International Journal of Sustainable Transportation survey were subjected to a bicycle theft in their lifetime as active cyclists.<ref>{{Cite journal|url = http://tram.mcgill.ca/Research/Publications/Cycling_theft.pdf|title = Breaking into bicycle theft: Insights from Montreal, Canada|last = van Lierop Grimsrud El-Geneidy|date = 2015|journal = International Journal of Sustainable Transportation|access-date = 30 September 2015}}</ref> Most bicycles have serial numbers that can be recorded to verify identity in case of theft.<ref>{{cite web\n| url = https://bikeindex.org/serials#fn-all-bikes-serials\n| title = Bike serial numbers\n| quote = Okay, fine, so maybe there are a few bikes without serial numbers, but this is rare and typical only on hand made bikes or really old bicycles.\n| access-date = 2 August 2017}}</ref>\n{{-}}"}},
{"article_title": "Banach space", "pageid": "3989", "revid": "1061485476", "timestamp": "2021-12-22T00:22:13Z", "history_paths": [["Banach space --- Introduction ---"]], "categories": ["banach spaces", "normed spaces", "science and technology in poland"], "heading_tree": {"Banach space --- Introduction ---": {"Definition": {"Topology": {}, "Completeness": {"Completions": {}}}, "General theory": {"Linear operators, isomorphisms": {"Continuous and bounded linear functions and seminorms": {}}, "Basic notions": {}, "Classical spaces": {}, "Banach algebras": {"Examples": {}}, "Dual space": {"Weak topologies": {}, "Examples of dual spaces": {}, "Bidual": {}}, "Banach's theorems": {}, "Reflexivity": {}, "Weak convergences of sequences": {"Results involving the  basis": {}, "Sequences, weak and weak* compactness": {}}}, "Schauder bases": {}, "Tensor product": {"Tensor products and the approximation property": {}}, "Some classification results": {"Characterizations of Hilbert space among Banach spaces": {}, "Metric classification": {}, "Topological classification": {}, "Spaces of continuous functions": {}}, "Examples": {}, "Derivatives": {}, "Generalizations": {}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Banach space --- Introduction ---": "{{short description|Normed vector space that is complete}}\nIn [[mathematics]], more specifically in [[functional analysis]], a '''Banach space''' (pronounced {{IPA-pl|\u02c8banax|}}) is a [[Complete metric space|complete]] [[normed vector space]]. Thus, a Banach space is a vector space with a [[Metric (mathematics)|metric]] that allows the computation of [[Norm (mathematics)|vector length]] and distance between vectors and is complete in the sense that a [[Cauchy sequence]] of vectors always converges to a well defined [[Limit of a sequence|limit]] that is within the space.\n\nBanach spaces are named after the Polish mathematician [[Stefan Banach]], who introduced this concept and studied it systematically in 1920\u20131922 along with [[Hans Hahn (mathematician)|Hans Hahn]] and [[Eduard Helly]].<ref>{{harvnb|Bourbaki|1987|loc=V.86}}<!--From French edition. Please check the "Historical Note" in the English edition.--></ref> \n[[Maurice Ren\u00e9 Fr\u00e9chet]] was the first to use the term "Banach space" and Banach in turn then coined the term "[[Fr\u00e9chet space]]."{{sfn|Narici|Beckenstein| 2011|p=93}}\nBanach spaces originally grew out of the study of [[function space]]s by [[David Hilbert|Hilbert]], [[Maurice Ren\u00e9 Fr\u00e9chet|Fr\u00e9chet]], and [[Frigyes Riesz|Riesz]] earlier in the century. Banach spaces play a central role in functional analysis. In other areas of [[analysis (mathematics)|analysis]], the spaces under study are often Banach spaces.\n\n \nA '''Banach space''' is a [[Complete metric space|complete]] [[normed space]] <math>(X, \\| \\cdot \\|).</math> \nA normed space is a pair<ref group=note>It is common to read "<math>X</math> is a normed space" instead of the more technically correct but (usually) pedantic "<math>(X, \\| \\cdot \\|)</math> is a normed space," especially if the norm is well known (for example, such as with [[Lp space|<math>L^p</math> spaces]]) or when there is no particular need to choose any one (equivalent) norm over any other (especially in the more abstract theory of [[topological vector space]]s), in which case this norm (if needed) is often automatically assumed to be denoted by <math>\\| \\cdot \\|.</math> However, in situations where emphasis is placed on the norm, it is common to see <math>(X, \\| \\cdot \\|)</math> written instead of <math>X.</math> The technically correct definition of normed spaces as pairs <math>(X, \\| \\cdot \\|)</math> may also become important in the context of [[category theory]] where the distinction between the categories of normed spaces, [[normable space]]s, [[metric space]]s, [[topological vector space|TVS]]s, [[topological space]]s, etc. is usually important.</ref> \n<math>(X, \\| \\cdot \\|)</math> consisting of a [[vector space]] <math>X</math> over a scalar field <math>\\mathbb{K}</math> (where <math>\\mathbb{K}</math> is <math>\\R</math> or <math>\\C</math>) together with a distinguished<ref group=note>This means that if the norm <math>\\| \\cdot \\|</math> is replaced with a different norm <math>\\|\\,\\cdot\\,\\|^{\\prime} \\text{ on } X,</math> then <math>(X, \\| \\cdot \\|)</math> is {{em|not}} the same normed space as <math>\\left(X, \\| \\cdot \\|^{\\prime}\\right),</math> even if the norms are equivalent. However, equivalence of norms on a given vector space does form an [[equivalence relation]].</ref> \n[[Norm (mathematics)|norm]] <math>\\| \\cdot \\| : X \\to \\R.</math> Like all norms, this norm induces a [[translation invariant]]<ref group=note name="translation invariant metric">A metric <math>D</math> on a vector space <math>X</math> is said to be '''translation invariant''' if <math>D(x, y) = D(x + z, y + z)</math> for all vectors <math>x, y, z \\in X.</math> This happens if and only if <math>D(x, y) = D(x - y, 0)</math> for all vectors <math>x, y \\in X.</math> A metric that is induced by a norm is always translation invariant.</ref> \n[[Metric (mathematics)|distance function]], called the '''canonical''' or [[Norm induced metric|('''norm''') '''induced metric''']], defined by<ref group=note>Because <math>\\|- z\\| = \\|z\\|</math> for all <math>z \\in X,</math> it is always true that <math>d(x, y) := \\|y - x\\| = \\|x - y\\|</math> for all <math>x, y \\in X.</math> So the order of <math>x</math> and <math>y</math> in this definition does not matter.</ref>\n<math display=block>d(x, y) := \\|y - x\\| = \\|x - y\\|</math>\nfor all vectors <math>x, y \\in X.</math> This makes <math>X</math> into a [[metric space]] <math>(X, d).</math> \nA sequence <math>x_{\\bull} = \\left(x_n\\right)_{n=1}^{\\infty}</math> is called {{nowrap|'''{{em|[[Cauchy sequence|<math>d</math>-Cauchy]]}}'''}} or {{nowrap|'''{{em|Cauchy in}} <math>(X, d)</math>'''}} or {{nowrap|'''{{em|<math>\\| \\cdot \\|</math>-Cauchy}}'''}} if for every real <math>r > 0,</math> there exists some index <math>N</math> such that\n<math display=block>d\\left(x_n, x_m\\right) = \\left\\|x_n - x_m\\right\\| < r</math>\nwhenever <math>m</math> and <math>n</math> are greater than <math>N.</math> \nThe canonical metric <math>d</math> is called a '''{{em|[[complete metric]]}}''' if the pair <math>(X, d)</math> is a {{em|[[complete metric space]]}}, which by definition means for every {{nowrap|<math>d</math>-[[Cauchy sequence]]}} <math>x_{\\bull} = \\left(x_n\\right)_{n=1}^{\\infty}</math> in <math>(X, d),</math> there exists some <math>x \\in X</math> such that\n<math display=block>\\lim_{n \\to \\infty} \\left\\|x_n - x\\right\\| = 0</math>\nwhere because <math>\\left\\|x_n - x\\right\\| = d\\left(x_n, x\\right),</math> this sequence's convergence to <math>x</math> can equivalently be expressed as:\n<math display=block>\\lim_{n \\to \\infty} x_n = x \\; \\text{ in } (X, d).</math>\n\nBy definition, the normed space <math>(X, \\| \\cdot \\|)</math> is a '''{{em|Banach space}}''' if the norm induced metric <math>d</math> is a [[complete metric]], or said differently, if <math>(X, d)</math> is a [[complete metric space]]. \nThe norm <math>\\| \\cdot \\|</math> of a normed space <math>(X, \\| \\cdot \\|)</math> is called a '''{{em|{{visible anchor|complete norm|Complete norm}}}}''' if <math>(X, \\| \\cdot \\|)</math> is a Banach space.\n\n'''L-semi-inner product'''\n\nFor any normed space <math>(X, \\| \\cdot \\|),</math> there exists an [[L-semi-inner product]] <math>\\langle \\cdot, \\cdot \\rangle</math> on <math>X</math> such that <math display=inline>\\|x\\| = \\sqrt{\\langle x, x \\rangle}</math> for all <math>x \\in X</math>; in general, there may be infinitely many L-semi-inner products that satisfy this condition. L-semi-inner products are a generalization of [[inner product]]s, which are what fundamentally distinguish [[Hilbert space]]s from all other Banach spaces. This shows that all normed spaces (and hence all Banach spaces) can be considered as being generalizations of (pre-)Hilbert spaces.\n\n'''Characterization in terms of series'''\n\nThe vector space structure allows one to relate the behavior of Cauchy sequences to that of converging [[Series (mathematics)#Generalizations|series of vectors]]. \nA normed space <math>X</math> is a Banach space if and only if each [[Absolute convergence|absolutely convergent]] series in <math>X</math> converges in <math>X,</math><ref>see Theorem 1.3.9, p. 20 in {{harvtxt|Megginson|1998}}.</ref>\n<math display=block>\\sum_{n=1}^{\\infty} \\|v_n\\| < \\infty \\quad \\text{ implies that } \\quad \\sum_{n=1}^{\\infty} v_n\\ \\ \\text{ converges in } \\ \\ X.</math>\n\n \nThe canonical metric <math>d</math> of a normed space <math>(X, \\|\\cdot\\|)</math> induces the usual [[metric topology]] <math>\\tau_d</math> on <math>X,</math> where this [[topology]], which is referred to as the '''canonical''' or '''norm induced topology'''. \nEvery normed space is automatically assumed to carry this [[Hausdorff space|Hausdorff]] topology, unless indicated otherwise. \nWith this topology, every Banach space is a [[Baire space]], although there exist normed spaces that are Baire but not Banach.{{sfn|Wilansky|2013|p=29}} The norm <math>\\|\\,\\cdot\\,\\| : \\left(X, \\tau_d\\right) \\to \\R</math> is always a [[continuous function]] with respect to the topology that it induces. \n\nThe open and closed balls of radius <math>r > 0</math> centered at a point <math>x \\in X</math> are, respectively, the sets \n<math display=block>B_r(x) := \\{z \\in X : \\|z - x\\| < r\\} \\qquad \\text{ and } \\qquad C_r(x) := \\{z \\in X : \\|z - x\\| \\leq r\\}.</math> \nAny such ball is a [[Convex set|convex]] and [[Bounded set (topological vector space)|bounded subset]] of <math>X,</math> but a [[Compact space|compact]] ball/[[Neighbourhood (topology)|neighborhood]] exists if and only if <math>X</math> is a [[finite-dimensional vector space]]. \nIn particular, no infinite\u2013dimensional normed space can be [[Locally compact space|locally compact]] or have the [[Montel space|Heine\u2013Borel property]]. \nIf <math>x_0</math> is a vector and <math>s \\neq 0</math> is a scalar then \n<math display=block>x_0 + s B_r(x) = B_{|s| r}\\left(x_0 + s x\\right) \\qquad \\text{ and } \\qquad x_0 + s C_r(x) = C_{|s| r}\\left(x_0 + s x\\right).</math> \nUsing <math>s := 1</math> shows that this norm-induced topology is [[Translation invariant topology|translation invariant]], which means that for any <math>x \\in X</math> and <math>S \\subseteq X,</math> the subset <math>S</math> is [[Open set|open]] (respectively, [[Closed set|closed]]) in <math>X</math> if and only if this is true of its translation <math>x + S := \\{x + s : s \\in S\\}.</math> \nConsequently, the norm induced topology is completely determined by any [[Neighbourhood system|neighbourhood basis]] at the origin. Some common neighborhood bases at the origin include:\n<math display=block>\\left\\{B_r(0) : r > 0\\right\\}, \\qquad \\left\\{C_r(0) : r > 0\\right\\}, \\qquad \\left\\{B_{r_n}(0) : n \\in \\N\\right\\}, \\qquad \\text{ or } \\qquad \\left\\{C_{r_n}(0) : n \\in \\N\\right\\}</math>\nwhere <math>\\left(r_n\\right)_{n=1}^{\\infty}</math> is a sequence in of positive real numbers that converges to <math>0</math> in <math>\\R</math> (such as <math>r_n := 1/n</math> or <math>r_n := 1/2^n</math> for instance). \nSo for example, every open subset <math>U</math> of <math>X</math> can be written as a union \n<math display=block>U = \\bigcup_{x \\in I} B_{r_x}(x) = \\bigcup_{x \\in I} x + B_{r_x}(0) = \\bigcup_{x \\in I} x + r_x B_1(0)</math>\nindexed by some subset <math>I \\subseteq U,</math> where every <math>r_x</math> is of the form <math>r_x = \\tfrac{1}{n_x}</math> for some integer <math>n_x > 0</math> (the closed ball can also be used instead of the open ball, although the indexing set <math>I</math> and radii <math>r_x</math> may need to be changed). \nAdditionally, <math>I</math> can always be chosen to be [[Countable set|countable]] if <math>X</math> is a {{em|[[separable space]]}}, which by definition means that <math>X</math> contains some countable [[Dense set|dense subset]]. \nThe [[Anderson\u2013Kadec theorem]] states that every infinite\u2013dimensional separable [[Fr\u00e9chet space]] is [[Homeomorphism|homeomorphic]] to the [[product space]] <math display=inline>\\prod_{i \\in \\N} \\R</math> of countably many copies of <math>\\R</math> (this homeomorphism need not be a [[linear map]]).<ref>{{harvnb|Bessaga|Pe\u0142czy\u0144ski|1975|p=189}}</ref> \nSince every Banach space is a Fr\u00e9chet space, this is also true of all infinite\u2013dimensional separable Banach spaces, including the separable [[Hilbert space|Hilbert]] [[L2-space|<math>\\ell</math><sup>2</sup> sequence space]] <math>\\ell^2(\\N)</math> with its usual norm <math>\\|\\cdot\\|_2,</math> where (in sharp contrast to finite\u2212dimensional spaces) <math>\\ell^2(\\N)</math> is also [[Homeomorphism|homeomorphic]] to its [[Unit sphere|unit {{em|sphere}}]] <math>\\left\\{x \\in \\ell^2(\\N) : \\|x\\|_2 = 1\\right\\}.</math>\n\nThis norm-induced topology also makes <math>\\left(X, \\tau_d\\right)</math> into what is known as a [[topological vector space]] (TVS), which by definition is a vector space endowed with a topology making the operations of addition and scalar multiplication continuous. It is emphasized that the TVS <math>\\left(X, \\tau_d\\right)</math> is {{em|only}} a vector space together with a certain type of topology; that is to say, when considered as a TVS, it is {{em|not}} associated with {{em|any}} particular norm or metric (both of which are "[[Forgetful functor|forgotten]]").\n\n'''Comparison of complete metrizable vector topologies'''\n\nThe [[Open mapping theorem (functional analysis)|open mapping theorem]] implies that if <math>\\tau \\text{ and } \\tau_2</math> are topologies on <math>X</math> that make both <math>(X, \\tau)</math> and <math>\\left(X, \\tau_2\\right)</math> into [[F-space|complete metrizable TVS]] (for example, Banach or [[Fr\u00e9chet space]]s) and if one topology is [[Comparison of topologies|finer or coarser]] than the other then they must be equal (that is, if <math>\\tau \\subseteq \\tau_2 \\text{ or } \\tau_2 \\subseteq \\tau \\text{ then } \\tau = \\tau_2</math>).{{sfn|Tr\u00e8ves|2006|pp=166\u2013173}}\nSo for example, if <math>(X, p) \\text{ and } (X, q)</math> are Banach spaces with topologies <math>\\tau_p \\text{ and } \\tau_q</math> and if one of these spaces has some open ball that is also an open subset of the other space (or equivalently, if one of <math>p : \\left(X, \\tau_q\\right) \\to \\R</math> or <math>q : \\left(X, \\tau_p\\right) \\to \\R</math> is continuous) then their topologies are identical and their [[Equivalent norm|norms are equivalent]]. \n\n \n'''Complete norms and equivalent norms'''\n\nTwo norms on a vector space are called '''[[Norm (mathematics)#Definition|{{em|equivalent}}]]''' if and only if they induce the same topology.<ref name="Conrad Equiv norms">{{cite web|url=https://kconrad.math.uconn.edu/blurbs/gradnumthy/equivnorms.pdf|title=Equivalence of norms|last=Conrad|first=Keith|website=kconrad.math.uconn.edu|access-date=September 7, 2020}}</ref> If <math>p</math> and <math>q</math> are two equivalent norms on a vector space <math>X</math> then <math>(X, p)</math> is a Banach space if and only if <math>(X, q)</math> is a Banach space. \nSee this footnote for an example of a continuous norm on a Banach space that is {{em|not}} equivalent to that Banach space's given norm.<ref group=note>Let <math>\\left(C([0, 1]), \\|\\cdot\\|_{\\infty}\\right)</math> denote the [[Continuous functions on a compact Hausdorff space|Banach space of continuous functions]] with the supremum norm and let <math>\\tau_{\\infty}</math> denote the topology on <math>C([0, 1])</math> induced by <math>\\|\\cdot\\|_{\\infty}.</math> The vector space <math>C([0, 1])</math> can be identified (via the [[inclusion map]]) as a proper [[Dense set|dense]] vector subspace <math>X</math> of the [[Lp-space|<math>L^1</math> space]] <math>\\left(L^1([0, 1]), \\|\\cdot\\|_1\\right),</math> which satisfies <math>\\|f\\|_1 \\leq \\|f\\|_{\\infty}</math> for all <math>f \\in X.</math> Let <math>p</math> denote the restriction of the [[Lp space|L<sup>1</sup>-norm]] to <math>X,</math> which makes this map <math>p : X \\to \\R</math> a norm on <math>X</math> (in general, the restriction of any norm to any vector subspace will necessarily again be a norm). The normed space <math>(X, p)</math> is {{em|not}} a Banach space since its completion is the proper superset <math>\\left(L^1([0, 1]), \\|\\cdot\\|_1\\right).</math> Because <math>p \\leq \\|\\cdot\\|_{\\infty}</math> holds on <math>X,</math> the map <math>p : \\left(X, \\tau_{\\infty}\\right) \\to \\R</math> is continuous. Despite this, the norm <math>p</math> is {{em|not}} equivalent to the norm <math>\\|\\cdot\\|_{\\infty}</math> (because <math>\\left(X, \\|\\cdot\\|_{\\infty}\\right)</math> is complete but <math>(X, p)</math> is not).</ref><ref name="Conrad Equiv norms"/> \nAll norms on a finite-dimensional vector space are equivalent and every finite-dimensional normed space is a Banach space.<ref>see Corollary 1.4.18, p. 32 in {{harvtxt|Megginson|1998}}.</ref>\n\n'''Complete norms vs complete metrics'''\n\nA metric <math>D</math> on a vector space <math>X</math> is induced by a norm on <math>X</math> if and only if <math>D</math> is [[translation invariant]]<ref group=note name="translation invariant metric"/> and '''{{em|absolutely homogeneous}}''', which means that <math>D(sx, sy) = |s| D(x, y)</math> for all scalars <math>s</math> and all <math>x, y \\in X,</math> in which case the function <math>\\|x\\| := D(x, 0)</math> defines a norm on <math>X</math> and the canonical metric induced by <math>\\|\\cdot\\|</math> is equal to <math>D.</math> \n\nSuppose that <math>(X, \\|\\cdot\\|)</math> is a normed space and that <math>\\tau</math> is the norm topology induced on <math>X.</math> Suppose that <math>D</math> is {{em|any}} [[Metric (mathematics)|metric]] on <math>X</math> such that the topology that <math>D</math> induces on <math>X</math> is equal to <math>\\tau.</math> If <math>D</math> is [[translation invariant]]<ref group=note name="translation invariant metric"/> then <math>(X, \\|\\cdot\\|)</math> is a Banach space if and only if <math>(X, D)</math> is a complete metric space.{{sfn|Narici|Beckenstein|2011|pp=47-66}} \nIf <math>D</math> is {{em|not}} translation invariant, then it may be possible for <math>(X, \\|\\cdot\\|)</math> to be a Banach space but for <math>(X, D)</math> to {{em|not}} be a complete metric space{{sfn|Narici|Beckenstein|2011|pp=47-51}} (see this footnote<ref group=note>The [[normed space]] <math>(\\R,|\\cdot |)</math> is a Banach space where the absolute value is a [[Norm (mathematics)|norm]] on the real line <math>\\R</math> that induces the usual [[Euclidean topology]] on <math>\\R.</math> Define a metric <math>D : \\R \\times \\R \\to \\R</math> on <math>\\R</math> by <math>D(x, y) =|\\arctan(x) - \\arctan(y)|</math> for all <math>x, y \\in \\R.</math> Just like {{nowrap|<math>|\\cdot|</math>{{hsp}}'s}} induced metric, the metric <math>D</math> also induces the usual Euclidean topology on <math>\\R.</math> However, <math>D</math> is not a complete metric because the sequence <math>x_{\\bull} = \\left(x_i\\right)_{i=1}^{\\infty}</math> defined by <math>x_i := i</math> is a [[Cauchy sequence|{{nowrap|<math>D</math>-Cauchy}} sequence]] but it does not converge to any point of <math>\\R.</math> As a consequence of not converging, this {{nowrap|<math>D</math>-Cauchy}} sequence cannot be a Cauchy sequence in <math>(\\R,|\\cdot |)</math> (that is, it is not a Cauchy sequence with respect to the norm <math>|\\cdot|</math>) because if it was {{nowrap|<math>|\\cdot|</math>-Cauchy,}} then the fact that <math>(\\R,|\\cdot |)</math> is a Banach space would imply that it converges (a contradiction).{{harvnb|Narici|Beckenstein|2011|pp=47\u201351}}</ref> for an example). In contrast, a theorem of Klee,{{sfn|Schaefer|Wolff|1999|p=35}}<ref name="Klee Inv metrics">{{Cite journal|last1=Klee|first1=V. L.|title=Invariant metrics in groups (solution of a problem of Banach)|year=1952|journal=Proc. Amer. Math. Soc.|volume=3|issue=3|pages=484\u2013487|url=https://www.ams.org/journals/proc/1952-003-03/S0002-9939-1952-0047250-4/S0002-9939-1952-0047250-4.pdf|doi=10.1090/s0002-9939-1952-0047250-4|doi-access=free}}</ref><ref group=note>The statement of the theorem is: Let <math>d</math> be {{em|any}} metric on a vector space <math>X</math> such that the topology <math>\\tau</math> induced by <math>d</math> on <math>X</math> makes <math>(X, \\tau)</math> into a topological vector space. If <math>(X, d)</math> is a [[complete metric space]] then <math>(X, \\tau)</math> is a [[complete topological vector space]].</ref> which also applies to all [[metrizable topological vector space]]s, implies that if there exists {{em|any}}<ref group=note>This metric <math>D</math> is {{em|not}} assumed to be translation-invariant. So in particular, this metric <math>D</math> does {{em|not}} even have to be induced by a norm.</ref> complete metric <math>D</math> on <math>X</math> that induces the norm topology <math>\\tau</math> on <math>X,</math> then <math>(X, \\|\\cdot\\|)</math> is a Banach space.\n\nA [[Fr\u00e9chet space]] is a [[locally convex topological vector space]] whose topology is induced by some translation-invariant complete metric. \nEvery Banach space is a Fr\u00e9chet space but not conversely; indeed, there even exist Fr\u00e9chet spaces on which no norm is a continuous function (such as the [[space of real sequences]] <math display=inline>\\R^{\\N} = \\prod_{i \\in \\N} \\R</math> with the [[product topology]]). \nHowever, the topology of every Fr\u00e9chet space is induced by some [[Countable set|countable]] family of real-valued (necessarily continuous) maps called [[seminorm]]s, which are generalizations of [[Norm (mathematics)|norm]]s. \nIt is even possible for a Fr\u00e9chet space to have a topology that is induced by a countable family of {{em|norms}} (such norms would necessarily be continuous)<ref group=note name=CharacterizationOfContinuityOfANorm>A norm (or [[seminorm]]) <math>p</math> on a topological vector space <math>(X, \\tau)</math> is continuous if and only if the topology <math>\\tau_p</math> that <math>p</math> induces on <math>X</math> is [[Comparison of topologies|coarser]] than <math>\\tau</math> (meaning, <math>\\tau_p \\subseteq \\tau</math>), which happens if and only if there exists some open ball <math>B</math> in <math>(X, p)</math> (such as maybe <math>\\{x \\in X : p(x) < 1\\}</math> for example) that is open in <math>(X, \\tau).</math></ref>{{sfn|Tr\u00e8ves|2006|pp=57\u201369}} \nbut to not be a Banach/[[normable space]] because its topology can not be defined by any {{em|single}} norm. \nAn example of such a space is the [[Fr\u00e9chet space]] <math>C^{\\infty}(K),</math> whose definition can be found in the article on [[spaces of test functions and distributions]]. \n\n'''Complete norms vs complete topological vector spaces'''\n\nThere is another notion of completeness besides metric completeness and that is the notion of a [[complete topological vector space]] (TVS) or TVS-completeness, which uses the theory of [[uniform space]]s. \nSpecifically, the notion of TVS-completeness uses a unique translation-invariant [[Uniformity (topology)|uniformity]], called the [[Complete topological vector space#Canonical uniformity|canonical uniformity]], that depends {{em|only}} on vector subtraction and the topology <math>\\tau</math> that the vector space is endowed with, and so in particular, this notion of TVS completeness is independent of whatever norm induced the topology <math>\\tau</math> (and even applies to TVSs that are {{em|not}} even metrizable). \nEvery Banach space is a complete TVS. Moreover, a normed space is a Banach space (that is, its norm-induced metric is complete) if and only if it is complete as a topological vector space. \nIf <math>(X, \\tau)</math> is a [[metrizable topological vector space]] (such as any norm induced topology, for example), then <math>(X, \\tau)</math> is a complete TVS if and only if it is a {{em|sequentially}} complete TVS, meaning that it is enough to check that every Cauchy {{em|sequence}} in <math>(X, \\tau)</math> converges in <math>(X, \\tau)</math> to some point of <math>X</math> (that is, there is no need to consider the more general notion of arbitrary Cauchy [[Net (mathematics)|nets]]). \n\nIf <math>(X, \\tau)</math> is a topological vector space whose topology is induced by {{em|some}} (possibly unknown) norm (such spaces are called {{em|[[Normable space|normable]]}} and [[Kolmogorov's normability criterion|they are characterized by]] being Hausdorff and having a [[Bounded set (topological vector space)|bounded]] [[Convex set|convex]] neighborhood of the origin), then <math>(X, \\tau)</math> is a complete topological vector space if and only if <math>X</math> may be assigned a [[Norm (mathematics)|norm]] <math>\\|\\cdot\\|</math> that induces on <math>X</math> the topology <math>\\tau</math> and also makes <math>(X, \\|\\cdot\\|)</math> into a Banach space. \nA [[Hausdorff space|Hausdorff]] [[locally convex topological vector space]] <math>X</math> is [[Normable space|normable]] if and only if its [[strong dual space]] <math>X^{\\prime}_b</math> is normable,{{sfn|Tr\u00e8ves|2006|p=201}} in which case <math>X^{\\prime}_b</math> is a Banach space (<math>X^{\\prime}_b</math> denotes the [[strong dual space]] of <math>X,</math> whose topology is a generalization of the [[dual norm]]-induced topology on the [[continuous dual space]] <math>X^{\\prime}</math>; see this footnote<ref group=note><math>X^{\\prime}</math> denotes the [[continuous dual space]] of <math>X.</math> When <math>X^{\\prime}</math> is endowed with the [[Strong topology (polar topology)|strong dual space topology]], also called the [[topology of uniform convergence]] on [[Bounded set (functional analysis)|bounded subsets]] of <math>X,</math> then this is indicated by writing <math>X^{\\prime}_b</math> (sometimes, the subscript <math>\\beta</math> is used instead of <math>b</math>). When <math>X</math> is a normed space with norm <math>\\|\\cdot\\|</math> then this topology is equal to the topology on <math>X^{\\prime}</math> induced by the [[dual norm]]. In this way, the [[Strong topology (polar topology)|strong topology]] is a generalization of the usual dual norm-induced topology on <math>X^{\\prime}.</math></ref> for more details). \nIf <math>X</math> is a [[Metrizable topological vector space|metrizable]] locally convex TVS, then <math>X</math> is normable if and only if <math>X^{\\prime}_b</math> is a [[Fr\u00e9chet\u2013Urysohn space]].<ref name="Gabriyelyan 2014">Gabriyelyan, S.S. [https://arxiv.org/pdf/1412.1497.pdf "On topological spaces and topological groups with certain local countable networks] (2014)</ref> \nThis shows that in the category of [[Locally convex topological vector space|locally convex TVSs]], Banach spaces are exactly those complete spaces that are both [[Metrizable topological vector space|metrizable]] and have metrizable [[strong dual space]]s. \n\n \nEvery normed space can be [[isometry|isometrically]] embedded onto a dense vector subspace of {{em|some}} Banach space, where this Banach space is called a '''[[Completion (metric space)|{{em|completion}}]]''' of the normed space. This Hausdorff completion is unique up to [[Isometry|isometric]] isomorphism.\n\nMore precisely, for every normed space <math>X,</math> there exist a Banach space <math>Y</math> and a mapping <math>T : X \\to Y</math> such that <math>T</math> is an [[Isometry|isometric mapping]] and <math>T(X)</math> is dense in <math>Y.</math> If <math>Z</math> is another Banach space such that there is an isometric isomorphism from <math>X</math> onto a dense subset of <math>Z,</math> then <math>Z</math> is isometrically isomorphic to <math>Y.</math>\nThis Banach space <math>Y</math> is the Hausdorff [[Complete metric space#Completion|'''{{em|completion}}''']] of the normed space <math>X.</math> The underlying metric space for <math>Y</math> is the same as the metric completion of <math>X,</math> with the vector space operations extended from <math>X</math> to <math>Y.</math> The completion of <math>X</math> is sometimes denoted by <math>\\widehat{X}.</math>\n\n \n <!-- This section is linked from [[Operator]] -->\n{{main|Bounded operator}}\nIf <math>X</math> and <math>Y</math> are normed spaces over the same [[ground field]] <math>\\mathbb{K},</math> the set of all [[Continuous function (topology)|continuous]] [[Linear transformation|<math>\\mathbb{K}</math>-linear maps]] <math>T : X \\to Y</math> is denoted by <math>B(X, Y).</math> In infinite-dimensional spaces, not all linear maps are continuous. A linear mapping from a normed space <math>X</math> to another normed space is continuous if and only if it is [[bounded operator|bounded]] on the closed [[Unit sphere|unit ball]] of <math>X.</math> Thus, the vector space <math>B(X, Y)</math> can be given the [[operator norm]]\n<math display=block>\\|T\\| = \\sup \\left\\{\\|Tx\\|_Y \\mid x\\in X,\\ \\|x\\|_X \\leq 1 \\right\\}.</math>\n\nFor <math>Y</math> a Banach space, the space <math>B(X, Y)</math> is a Banach space with respect to this norm.\n\nIf <math>X</math> is a Banach space, the space <math>B(X) = B(X, X)</math> forms a unital [[Banach algebra]]; the multiplication operation is given by the composition of linear maps.\n\nIf <math>X</math> and <math>Y</math> are normed spaces, they are '''isomorphic normed spaces''' if there exists a linear bijection <math>T : X \\to Y</math> such that <math>T</math> and its inverse <math>T^{-1}</math> are continuous. If one of the two spaces <math>X</math> or <math>Y</math> is complete (or [[Reflexive space|reflexive]], [[Separable space|separable]], etc.) then so is the other space. Two normed spaces <math>X</math> and <math>Y</math> are '''isometrically isomorphic''' if in addition, <math>T</math> is an [[isometry]], that is, <math>\\|T(x)\\| = \\|x\\|</math> for every <math>x</math> in <math>X.</math> The [[Banach\u2013Mazur distance]] <math>d(X, Y)</math> between two isomorphic but not isometric spaces <math>X</math> and <math>Y</math> gives a measure of how much the two spaces <math>X</math> and <math>Y</math> differ.\n\n \nEvery [[continuous linear operator]] is a [[bounded linear operator]] and if dealing only with normed spaces then the converse is also true. That is, a [[linear operator]] between two normed spaces is [[Bounded linear operator|bounded]] if and only if it is a [[continuous function]]. So in particular, because the scalar field (which is <math>\\R</math> or <math>\\C</math>) is a normed space, a [[linear functional]] on a normed space is a [[bounded linear functional]] if and only if it is a [[continuous linear functional]]. This allows for continuity-related results (like those below) to be applied to Banach spaces. Although boundedness is the same as continuity for linear maps between normed spaces, the term "bounded" is more commonly used when dealing primarily with Banach spaces. \n\nIf <math>f : X \\to \\R</math> is a [[subadditive function]] (such as a norm, a [[sublinear function]], or real linear functional), then{{sfn|Narici|Beckenstein|2011|pp=192-193}} <math>f</math> is [[Continuity at a point|continuous at the origin]] if and only if <math>f</math> is [[uniformly continuous]] on all of <math>X</math>; and if in addition <math>f(0) = 0</math> then <math>f</math> is continuous if and only if its [[absolute value]] <math>|f| : X \\to [0, \\infty)</math> is continuous, which happens if and only if <math>\\{x \\in X : |f(x)| < 1\\}</math> is an open subset of <math>X.</math>{{sfn|Narici|Beckenstein|2011|pp=192-193}}<ref group=note>The fact that <math>\\{x \\in X : |f(x)| < 1\\}</math> being open implies that <math>f : X \\to \\R</math> is continuous simplifies proving continuity because this means that it suffices to show that <math>\\{x \\in X : \\left|f(x) - f\\left(x_0\\right)\\right| < r\\}</math> is open for <math>r := 1</math> and at <math>x_0 := 0</math> (where <math>f(0) = 0</math>) rather than showing this for {{em|all}} real <math>r > 0</math> and {{em|all}} <math>x_0 \\in X.</math></ref> \nAnd very importantly for applying the [[Hahn-Banach theorem]],  a linear functional <math>f</math> is continuous if and only if this is true of its [[real part]] <math>\\operatorname{Re} f</math> and moreover, <math>\\|\\operatorname{Re} f\\| = \\|f\\|</math> and [[Real and imaginary parts of a linear functional|the real part <math>\\operatorname{Re} f</math> completely determines]] <math>f,</math> which is why the Hahn-Banach theorem is often stated only for real linear functionals.\nAlso, a linear functional <math>f</math> on <math>X</math> is continuous if and only if the [[seminorm]] <math>|f|</math> is continuous, which happens if and only if there exists a continuous seminorm <math>p : X \\to \\R</math> such that <math>|f| \\leq p</math>; this last statement involving the linear functional <math>f</math> and seminorm <math>p</math> is encountered in many versions of the Hahn-Banach theorem.\n\n \nThe Cartesian product <math>X \\times Y</math> of two normed spaces is not canonically equipped with a norm. However, several equivalent norms are commonly used,<ref>see {{harvtxt|Banach|1932}}, p. 182.</ref> such as\n<math display=block>\\|(x, y)\\|_1 = \\|x\\| + \\|y\\|, \\qquad \\|(x, y)\\|_\\infty = \\max (\\|x\\|, \\|y\\|)</math>\nand give rise to isomorphic normed spaces. In this sense, the product <math>X \\times Y</math> (or the direct sum <math>X \\oplus Y</math>) is complete if and only if the two factors are complete.\n\nIf <math>M</math> is a [[Closed set|closed]] [[linear subspace]] of a normed space <math>X,</math> there is a natural norm on the '''quotient space''' <math>X / M,</math>\n<math display=block>\\|x + M\\| = \\inf\\limits_{m \\in M} \\|x + m\\|.</math>\n\nThe quotient <math>X / M</math> is a Banach space when <math>X</math> is complete.<ref name="Caro17">see pp. 17\u201319 in {{harvtxt|Carothers|2005}}.</ref> The '''quotient map''' from <math>X</math> onto <math>X / M,</math> sending <math>x \\in X</math> to its class <math>x + M,</math> is linear, onto and has norm <math>1,</math> except when <math>M = X,</math> in which case the quotient is the null space.\n\nThe closed linear subspace <math>M</math> of <math>X</math> is said to be a '''[[complemented subspace]]''' of <math>X</math> if <math>M</math> is the [[Range of a function|range]] of a [[Surjection|surjective]] bounded linear [[Projection (linear algebra)|projection]] <math>P : X \\to M.</math> In this case, the space <math>X</math> is isomorphic to the direct sum of <math>M</math> and <math>\\ker P,</math> the kernel of the projection <math>P.</math>\n\nSuppose that <math>X</math> and <math>Y</math> are Banach spaces and that <math>T \\in B(X, Y).</math> There exists a '''canonical factorization''' of <math>T</math> as<ref name="Caro17" />\n<math display=block>T = T_1 \\circ \\pi, \\ \\ \\ T : X \\ \\overset{\\pi}{\\longrightarrow}\\ X / ker(T) \\ \\overset{T_1}{\\longrightarrow} \\ Y</math>\nwhere the first map <math>\\pi</math> is the quotient map, and the second map <math>T_1</math> sends every class <math>x + \\ker T</math> in the quotient to the image <math>T(x)</math> in <math>Y.,</math> This is well defined because all elements in the same class have the same image. The mapping <math>T_1</math> is a linear bijection from <math>X / \\ker T</math> onto the range <math>T(X),</math> whose inverse need not be bounded.\n\n \nBasic examples<ref>see {{harvtxt|Banach|1932}}, pp. 11-12.</ref> of Banach spaces include: the [[Lp space]]s <math>L^p</math> and their special cases, the [[sequence space (mathematics)|sequence spaces]] <math>\\ell^p</math> that consist of scalar sequences indexed by [[natural number]]s <math>\\N</math>; among them, the space <math>\\ell^1</math> of [[Absolute convergence|absolutely summable]] sequences and the space <math>\\ell^2</math> of square summable sequences; the space <math>c_0</math> of sequences tending to zero and the space <math>\\ell^{\\infty}</math> of bounded sequences; the space <math>C(K)</math> of continuous scalar functions on a compact Hausdorff space <math>K,</math> equipped with the max norm,\n<math display=block>\\|f\\|_{C(K)} = \\max \\{ |f(x)| : x \\in K \\}, \\quad f \\in C(K).</math>\n\nAccording to the [[Banach\u2013Mazur theorem]], every Banach space is isometrically isomorphic to a subspace of some <math>C(K).</math><ref>see {{harvtxt|Banach|1932}}, Th. 9 p. 185.</ref> For every separable Banach space <math>X,</math> there is a closed subspace <math>M</math> of <math>\\ell^1</math> such that <math>X := \\ell^1 / M.</math><ref>see Theorem 6.1, p. 55 in {{harvtxt|Carothers|2005}}</ref>\n\nAny [[Hilbert space]] serves as an example of a Banach space. A Hilbert space <math>H</math> on <math>\\mathbb{K} = \\R, \\C</math> is complete for a norm of the form\n<math display=block>\\|x\\|_H = \\sqrt{\\langle x, x \\rangle},</math>\nwhere\n<math display=block>\\langle \\cdot, \\cdot \\rangle : H \\times H \\to \\mathbb{K}</math>\nis the [[Inner product space|inner product]], linear in its first argument that satisfies the following:\n<math display=block>\\begin{align}\n\\langle y, x \\rangle &= \\overline{\\langle x, y \\rangle}, \\quad \\text{ for all } x, y \\in H \\\\\n\\langle x, x \\rangle & \\geq 0, \\quad \\text{ for all } x \\in H \\\\\n\\langle x,x \\rangle = 0 \\text{ if and only if } x &= 0.\n\\end{align}</math>\n\nFor example, the space <math>L^2</math> is a Hilbert space.\n\nThe [[Hardy space]]s, the [[Sobolev space]]s are examples of Banach spaces that are related to <math>L^p</math> spaces and have additional structure. They are important in different branches of analysis, [[Harmonic analysis]] and [[Partial differential equation]]s among others.\n\n \nA '''[[Banach algebra]]''' is a Banach space <math>A</math> over <math>\\mathbb{K} = \\R</math> or <math>\\Complex,</math> together with a structure of [[Algebra over a field|algebra over <math>\\mathbb{K}</math>]], such that the product map <math>A \\times A \\ni (a, b) \\mapsto ab \\in A</math> is continuous. An equivalent norm on <math>A</math> can be found so that <math>\\|ab\\| \\leq \\|a\\| \\|b\\|</math> for all <math>a, b \\in A.</math>\n\n \n* The Banach space <math>C(K)</math> with the pointwise product, is a Banach algebra.\n* The [[disk algebra]] <math>A(\\mathbf{D})</math> consists of functions [[Holomorphic function|holomorphic]] in the open unit disk <math>D \\subseteq \\Complex</math> and continuous on its [[Closure (topology)|closure]]: <math>\\overline{\\mathbf{D}}.</math> Equipped with the max norm on <math>\\overline{\\mathbf{D}},</math> the disk algebra <math>A(\\mathbf{D})</math> is a closed subalgebra of <math>C\\left(\\overline{\\mathbf{D}}\\right).</math>\n* The [[Wiener algebra]] <math>A(\\mathbf{T})</math> is the algebra of functions on the unit circle <math>\\mathbf{T}</math> with absolutely convergent Fourier series. Via the map associating a function on <math>\\mathbf{T}</math> to the sequence of its Fourier coefficients, this algebra is isomorphic to the Banach algebra <math>\\ell^1(Z),</math> where the product is the [[Convolution#Discrete convolution|convolution]] of sequences.\n* For every Banach space <math>X,</math> the space <math>B(X)</math> of bounded linear operators on <math>X,</math> with the composition of maps as product, is a Banach algebra.\n* A [[C*-algebra]] is a complex Banach algebra <math>A</math> with an [[Antilinear map|antilinear]] [[Involution (mathematics)|involution]] <math>a \\mapsto a^*</math> such that <math>\\left\\|a^* a\\right\\| = \\|a\\|^2.</math> The space <math>B(H)</math> of bounded linear operators on a Hilbert space <math>H</math> is a fundamental example of C*-algebra. The [[Gelfand\u2013Naimark theorem]] states that every C*-algebra is isometrically isomorphic to a C*-subalgebra of some <math>B(H).</math> The space <math>C(K)</math> of complex continuous functions on a compact Hausdorff space <math>K</math> is an example of commutative C*-algebra, where the involution associates to every function <math>f</math> its [[complex conjugate]] <math>\\overline{f}.</math>\n\n {{main|Dual space}}\nIf <math>X</math> is a normed space and <math>\\mathbb{K}</math> the underlying [[Field (mathematics)|field]] (either the [[Real number|real]] or the [[complex number]]s), the [[Dual space#Continuous dual space|'''continuous dual space''']] is the space of continuous linear maps from <math>X</math> into <math>\\mathbb{K},</math> or '''continuous linear functionals'''. \nThe notation for the continuous dual is <math>X^{\\prime} = B(X, \\mathbb{K})</math> in this article.<ref>Several books about functional analysis use the notation <math>X^*</math> for the continuous dual, for example {{harvtxt|Carothers|2005}}, {{harvtxt|Lindenstrauss|Tzafriri|1977}}, {{harvtxt|Megginson|1998}}, {{harvtxt|Ryan|2002}}, {{harvtxt|Wojtaszczyk|1991}}.</ref> \nSince <math>\\mathbb{K}</math> is a Banach space (using the [[absolute value]] as norm), the dual <math>X^{\\prime}</math> is a Banach space, for every normed space <math>X.</math>\n\nThe main tool for proving the existence of continuous linear functionals is the [[Hahn\u2013Banach theorem]].\n\n:'''Hahn\u2013Banach theorem.''' Let <math>X</math> be a [[vector space]] over the field <math>\\mathbb{K} = \\R, \\C.</math> Let further\n:* <math>Y \\subseteq X</math> be a [[linear subspace]],\n:* <math>p : X \\to \\R</math> be a [[sublinear function]] and\n:* <math>f : Y \\to \\mathbb{K}</math> be a [[linear functional]] so that <math>\\operatorname{Re}(f(y)) \\leq p(y)</math> for all <math>y \\in Y.</math> \n:Then, there exists a linear functional <math>F : X \\to \\mathbb{K}</math>} so that <math display=block>F\\big\\vert_Y = f, \\quad \\text{ and } \\quad \\text{ for all } x \\in X, \\ \\ \\operatorname{Re}(F(x)) \\leq p(x).</math>\n\nIn particular, every continuous linear functional on a subspace of a normed space can be continuously extended to the whole space, without increasing the norm of the functional.<ref>Theorem 1.9.6, p. 75 in {{harvtxt|Megginson|1998}}</ref> \nAn important special case is the following: for every vector <math>x</math> in a normed space <math>X,</math> there exists a continuous linear functional <math>f</math> on <math>X</math> such that\n<math display=block>f(x) = \\|x\\|_X, \\quad \\|f\\|_{X^{\\prime}} \\leq 1.</math>\n\nWhen <math>x</math> is not equal to the <math>\\mathbf{0}</math> vector, the functional <math>f</math> must have norm one, and is called a '''norming functional''' for <math>x.</math>\n\nThe [[Hahn\u2013Banach separation theorem]] states that two disjoint non-empty [[convex set]]s in a real Banach space, one of them open, can be separated by a closed [[Affine space|affine]] [[hyperplane]]. \nThe open convex set lies strictly on one side of the hyperplane, the second convex set lies on the other side but may touch the hyperplane.<ref>see also Theorem 2.2.26, p. 179 in {{harvtxt|Megginson|1998}}</ref>\n\nA subset <math>S</math> in a Banach space <math>X</math> is '''total''' if the [[linear span]] of <math>S</math> is [[Dense set|dense]] in <math>X.</math> The subset <math>S</math> is total in <math>X</math> if and only if the only continuous linear functional that vanishes on <math>S</math> is the <math>\\mathbf{0}</math> functional: this equivalence follows from the Hahn\u2013Banach theorem.\n\nIf <math>X</math> is the direct sum of two closed linear subspaces <math>M</math> and <math>N,</math> then the dual <math>X^{\\prime}</math> of <math>X</math> is isomorphic to the direct sum of the duals of <math>M</math> and <math>N.</math><ref name="Caro19">see p. 19 in {{harvtxt|Carothers|2005}}.</ref> \nIf <math>M</math> is a closed linear subspace in <math>X,</math> one can associate the {{em|orthogonal of}} <math>M</math> in the dual,\n<math display=block>M^{bot} = \\left\\{ x^{\\prime} \\in X : x^{\\prime}(m) = 0, \\ \\text{ for all } m \\in M \\right\\}.</math>\n\nThe orthogonal <math>M^{\\bot}</math> is a closed linear subspace of the dual. The dual of <math>M</math> is isometrically isomorphic to <math>X^{\\prime} / M^{\\bot}.</math> \nThe dual of <math>X / M</math> is isometrically isomorphic to <math>M^{\\bot}.</math><ref>Theorems 1.10.16, 1.10.17 pp.94\u201395 in {{harvtxt|Megginson|1998}}</ref>\n\nThe dual of a separable Banach space need not be separable, but:\n\n:'''Theorem.'''<ref>Theorem 1.12.11, p. 112 in {{harvtxt|Megginson|1998}}</ref> Let <math>X</math> be a normed space. If <math>X^{\\prime}</math> is [[Separable space|separable]], then <math>X</math> is separable.\n\nWhen <math>X^{\\prime}</math> is separable, the above criterion for totality can be used for proving the existence of a countable total subset in <math>X.</math>\n\n \nThe '''[[weak topology]]''' on a Banach space <math>X</math> is the [[Comparison of topologies|coarsest topology]] on <math>X</math> for which all elements <math>x^{\\prime}</math> in the continuous dual space <math>X^{\\prime}</math> are continuous. \nThe norm topology is therefore [[Comparison of topologies|finer]] than the weak topology. \nIt follows from the Hahn\u2013Banach separation theorem that the weak topology is [[Hausdorff space|Hausdorff]], and that a norm-closed [[Convex set|convex subset]] of a Banach space is also weakly closed.<ref>Theorem 2.5.16, p. 216 in {{harvtxt|Megginson|1998}}.</ref> \nA norm-continuous linear map between two Banach spaces <math>X</math> and <math>Y</math> is also '''weakly continuous''', that is, continuous from the weak topology of <math>X</math> to that of <math>Y.</math><ref>see II.A.8, p. 29 in {{harvtxt|Wojtaszczyk|1991}}</ref>\n\nIf <math>X</math> is infinite-dimensional, there exist linear maps which are not continuous. The space <math>X^*</math> of all linear maps from <math>X</math> to the underlying field <math>\\mathbb{K}</math> (this space <math>X^*</math> is called the [[Dual space#Algebraic dual space|algebraic dual space]], to distinguish it from <math>X^{\\prime}</math> also induces a topology on <math>X</math> which is [[finer topology|finer]] than the weak topology, and much less used in functional analysis.\n\nOn a dual space <math>X^{\\prime},</math> there is a topology weaker than the weak topology of <math>X^{\\prime},</math> called [[weak topology|'''weak* topology''']]. \nIt is the coarsest topology on <math>X^{\\prime}</math> for which all evaluation maps <math>x^{\\prime} \\in X^{\\prime} \\mapsto x^{\\prime}(x),</math> where <math>x</math> ranges over <math>X,</math> are continuous. \nIts importance comes from the [[Banach\u2013Alaoglu theorem]].\n\n:'''[[Banach\u2013Alaoglu theorem]].''' Let <math>X</math> be a [[normed vector space]]. Then the [[Closed set|closed]] [[Ball (mathematics)|unit ball]] <math>B = \\left\\{ x \\in X : \\|x\\| \\leq 1 \\right\\}</math> of the dual space is [[Compact space|compact]] in the weak* topology.\n\nThe Banach\u2013Alaoglu theorem can be proved using [[Tychonoff's theorem]] about infinite products of compact Hausdorff spaces. \nWhen <math>X</math> is separable, the unit ball <math>B^{\\prime}</math> of the dual is a [[Metrizable space|metrizable]] compact in the weak* topology.<ref name="DualBall">see Theorem 2.6.23, p. 231 in {{harvtxt|Megginson|1998}}.</ref>\n\n \nThe dual of <math>c_0</math> is isometrically isomorphic to <math>\\ell^1</math>: for every bounded linear functional <math>f</math> on <math>c_0,</math> there is a unique element <math>y = \\left\\{ y_n \\right\\} \\in \\ell^1</math> such that\n<math display=block>f(x) = \\sum_{n \\in \\N} x_n y_n, \\qquad x = \\{x_n\\} \\in c_0, \\ \\ \\text{and} \\ \\ \\|f\\|_{(c_0)'} = \\|y\\|_{\\ell_1}. </math>\n\nThe dual of <math>\\ell^1</math> is isometrically isomorphic to <math>\\ell^{\\infty}</math>}. \nThe dual of [[Lp space#Properties of Lp spaces|Lebesgue space]] <math>L^p([0, 1])</math> is isometrically isomorphic to <math>L^q([0, 1])</math> when <math>1 \\leq p < \\infty</math> and <math>\\frac{1}{p} + \\frac{1}{q} = 1.</math> \n\nFor every vector <math>y</math> in a Hilbert space <math>H,</math> the mapping\n<math display=block>x \\in H \\to f_y(x) = \\langle x, y \\rangle</math>\n\ndefines a continuous linear functional <math>f_y</math> on <math>H.</math>The [[Riesz representation theorem]] states that every continuous linear functional on <math>H</math> is of the form <math>f_y</math> for a uniquely defined vector <math>y</math> in <math>H.</math>\nThe mapping <math>y \\in H \\to f_y</math> is an [[Antilinear map|antilinear]] isometric bijection from <math>H</math> onto its dual <math>H^{\\prime}.</math> \nWhen the scalars are real, this map is an isometric isomorphism.\n\nWhen <math>K</math> is a compact Hausdorff topological space, the dual <math>M(K)</math> of <math>C(K)</math> is the space of [[Radon measure]]s in the sense of Bourbaki.<ref>see N. Bourbaki, (2004), "Integration I", Springer Verlag, {{ISBN|3-540-41129-1}}.</ref> \nThe subset <math>P(K)</math> of <math>M(K)</math> consisting of non-negative measures of mass 1 ([[probability measure]]s) is a convex w*-closed subset of the unit ball of <math>M(K).</math> \nThe [[extreme point]]s of <math>P(K)</math> are the [[Dirac measure]]s on <math>K.</math> \nThe set of Dirac measures on <math>K,</math> equipped with the w*-topology, is [[Homeomorphism|homeomorphic]] to <math>K.</math>\n\n:[[Banach\u2013Stone theorem|'''Banach\u2013Stone Theorem.''']] If <math>K</math> and <math>L</math> are compact Hausdorff spaces and if <math>C(K)</math> and <math>C(L)</math> are isometrically isomorphic, then the topological spaces <math>K</math> and <math>L</math> are [[homeomorphic]].<ref name= Eilenberg /><ref>see also {{harvtxt|Banach|1932}}, p. 170 for metrizable <math>K</math> and <math>L.</math></ref>\n\nThe result has been extended by Amir<ref>{{cite journal |first=Dan |last=Amir |title=On isomorphisms of continuous function spaces |journal=[[Israel Journal of Mathematics]] |volume=3 |year=1965 |issue=4 |pages=205\u2013210 |doi=10.1007/bf03008398 |doi-access=free |s2cid=122294213 }}</ref> and Cambern<ref>{{cite journal |first=M. |last=Cambern |title=A generalized Banach\u2013Stone theorem |journal=Proc. Amer. Math. Soc. |volume=17 |year=1966 |issue=2 |pages=396\u2013400 |doi=10.1090/s0002-9939-1966-0196471-9|doi-access=free}} And {{cite journal |first=M. |last=Cambern |title=On isomorphisms with small bound |journal=Proc. Amer. Math. Soc. |volume=18 |year=1967 |issue=6 |pages=1062\u20131066 |doi=10.1090/s0002-9939-1967-0217580-2|doi-access=free}}</ref> to the case when the multiplicative [[Banach\u2013Mazur compactum|Banach\u2013Mazur distance]] between <math>C(K)</math> and <math>C(L)</math> is <math>< 2.</math> \nThe theorem is no longer true when the distance is <math> = 2.</math><ref>{{cite journal |first=H. B. |last=Cohen |title=A bound-two isomorphism between <math>C(X)</math> Banach spaces |journal=Proc. Amer. Math. Soc. |volume=50 |year=1975 |pages=215\u2013217 |doi=10.1090/s0002-9939-1975-0380379-5|doi-access=free }}</ref>\n\nIn the commutative [[Banach algebra]] <math>C(K),</math> the [[Banach algebra#Ideals and characters|maximal ideals]] are precisely kernels of Dirac measures on <math>K,</math>\n<math display=block>I_x = \\ker \\delta_x = \\{f \\in C(K) : f(x) = 0\\}, \\quad x \\in K.</math>\n\nMore generally, by the [[Gelfand\u2013Mazur theorem]], the maximal ideals of a unital commutative Banach algebra can be identified with its [[Banach algebra#Ideals and characters|characters]]\u2014not merely as sets but as topological spaces: the former with the [[hull-kernel topology]] and the latter with the w*-topology. \nIn this identification, the maximal ideal space can be viewed as a w*-compact subset of the unit ball in the dual <math>A^{\\prime}.</math> \n\n:'''Theorem.''' If <math>K</math> is a compact Hausdorff space, then the maximal ideal space <math>\\Xi</math> of the Banach algebra <math>C(K)</math> is [[homeomorphic]] to <math>K.</math><ref name=Eilenberg>{{cite journal |last=Eilenberg |first=Samuel |title=Banach Space Methods in Topology |journal=[[Annals of Mathematics]] |date=1942 |volume=43 |issue=3 |pages=568\u2013579 |doi=10.2307/1968812|jstor=1968812 }}</ref>\n\nNot every unital commutative Banach algebra is of the form <math>C(K)</math> for some compact Hausdorff space <math>K.</math> However, this statement holds if one places <math>C(K)</math> in the smaller category of commutative [[C*-algebra]]s. \n[[Israel Gelfand|Gelfand's]] [[Gelfand representation|representation theorem]] for commutative C*-algebras states that every commutative unital ''C''*-algebra <math>A</math> is isometrically isomorphic to a <math>C(K)</math> space.<ref>See for example {{cite book |first=W. |last=Arveson |year=1976 |title=An Invitation to C*-Algebra |publisher=Springer-Verlag |isbn=0-387-90176-0 }}</ref> \nThe Hausdorff compact space <math>K</math> here is again the maximal ideal space, also called the [[Spectrum of a C*-algebra#Examples|spectrum]] of <math>A</math> in the C*-algebra context.\n\n {{See also|Bidual|Reflexive space|Semi-reflexive space}}\n\nIf <math>X</math> is a normed space, the (continuous) dual <math>X^{\\prime\\prime}</math> of the dual <math>X^{\\prime}</math> is called '''{{visible anchor|bidual}}''', or '''{{visible anchor|second dual}}''' of <math>X.</math> \nFor every normed space <math>X,</math> there is a natural map,\n<math display="block>\\begin{cases} F_X : X \\to X^{\\prime\\prime} \\\\ F_X(x) (f) = f(x) & \\text{ for all } x \\in X, \\text{ and for all } f \\in X^{\\prime}\\end{cases}</math>\n\nThis defines <math>F_X(x)</math> as a continuous linear functional on <math>X^{\\prime},</math> that is, an element of <math>X^{\\prime\\prime}.</math> The map <math>F_X : x \\to F_X(x)</math> is a linear map from <math>X</math> to <math>X^{\\prime\\prime}.</math> \nAs a consequence of the existence of a [[Banach space#Dual space|norming functional]] <math>f</math> for every <math>x \\in X,</math> this map <math>F_X</math> is isometric, thus [[injective]].\n\nFor example, the dual of <math>X = c_0</math> is identified with <math>\\ell^1,</math> and the dual of <math>\\ell^1</math> is identified with <math>\\ell^{\\infty},</math> the space of bounded scalar sequences. \nUnder these identifications, <math>F_X</math> is the inclusion map from <math>c_0</math> to <math>\\ell^{\\infty}.</math> It is indeed isometric, but not onto.\n\nIf <math>F_X</math> is [[surjective]], then the normed space <math>X</math> is called '''reflexive''' (see [[Banach space#Reflexivity|below]]). \nBeing the dual of a normed space, the bidual <math>X^{\\prime\\prime}</math> is complete, therefore, every reflexive normed space is a Banach space.\n\nUsing the isometric embedding <math>F_X,</math> it is customary to consider a normed space <math>X</math> as a subset of its bidual. \nWhen <math>X</math> is a Banach space, it is viewed as a closed linear subspace of <math>X^{\\prime\\prime}.</math> If <math>X</math> is not reflexive, the unit ball of <math>X</math> is a proper subset of the unit ball of <math>X^{\\prime\\prime}.</math> \nThe [[Goldstine theorem]] states that the unit ball of a normed space is weakly*-dense in the unit ball of the bidual. \nIn other words, for every <math>x^{\\prime\\prime}</math> in the bidual, there exists a [[Net (mathematics)|net]] <math>\\left(x_i\\right)_{i \\in I}</math> in <math>X</math> so that\n<math display="block>\\sup_{i \\in I} \\left\\|x_i\\right\\| \\leq \\|x^{\\prime\\prime}\\|, \\ \\ x^{\\prime\\prime}(f) = \\lim_i f\\left(x_i\\right), \\quad f \\in X^{\\prime}.</math>\n\nThe net may be replaced by a weakly*-convergent sequence when the dual <math>X^{\\prime}</math> is separable. \nOn the other hand, elements of the bidual of <math>\\ell^1</math> that are not in <math>\\ell^1</math> cannot be weak*-limit of {{em|sequences}} in <math>\\ell^1,</math> since <math>\\ell^1</math> is [[Banach space#Weak convergences of sequences|weakly sequentially complete]].\n\n \nHere are the main general results about Banach spaces that go back to the time of Banach's book ({{harvtxt|Banach|1932}}) and are related to the [[Baire category theorem]]. \nAccording to this theorem, a complete metric space (such as a Banach space, a [[Fr\u00e9chet space]] or an [[F-space]]) cannot be equal to a union of countably many closed subsets with empty [[Interior (topology)|interiors]]. \nTherefore, a Banach space cannot be the union of countably many closed subspaces, unless it is already equal to one of them; a Banach space with a countable [[Hamel basis]] is finite-dimensional.\n\n:'''[[Uniform boundedness principle|Banach\u2013Steinhaus Theorem.]]''' Let <math>X</math> be a Banach space and <math>Y</math> be a [[normed vector space]]. Suppose that <math>F</math> is a collection of continuous linear operators from <math>X</math> to <math>Y.</math> The uniform boundedness principle states that if for all <math>x</math> in <math>X</math> we have <math>\\sup_{T \\in F} \\|T(x)\\|_Y < \\infty,</math> then <math>\\sup_{T \\in F} \\|T\\|_Y < \\infty.</math>\n\nThe Banach\u2013Steinhaus theorem is not limited to Banach spaces. \nIt can be extended for example to the case where <math>X</math> is a [[Fr\u00e9chet space]], provided the conclusion is modified as follows: under the same hypothesis, there exists a neighborhood <math>U</math> of <math>\\mathbf{0}</math> in <math>X</math> such that all <math>T</math> in <math>F</math> are uniformly bounded on <math>U,</math>\n<math display=block>\\sup_{T \\in F} \\sup_{x \\in U} \\; \\|T(x)\\|_Y < \\infty.</math>\n\n:'''[[Open mapping theorem (functional analysis)|The Open Mapping Theorem.]]''' Let <math>X</math> and <math>Y</math> be Banach spaces and <math>T : X \\to Y</math> be a surjective continuous linear operator, then <math>T</math> is an open map.\n\n:'''Corollary.''' Every one-to-one bounded linear operator from a Banach space onto a Banach space is an isomorphism.\n\n:'''The First Isomorphism Theorem for Banach spaces.''' Suppose that <math>X</math> and <math>Y</math> are Banach spaces and that <math>T \\in B(X, Y).</math> Suppose further that the range of <math>T</math> is closed in <math>Y.</math> Then <math>X / \\ker T</math> is isomorphic to <math>T(X).</math> \n\nThis result is a direct consequence of the preceding ''Banach isomorphism theorem'' and of the canonical factorization of bounded linear maps.\n\n:'''Corollary.''' If a Banach space <math>X</math> is the internal direct sum of closed subspaces <math>M_1, \\ldots, M_n,</math> then <math>X</math> is isomorphic to <math>M_1 \\oplus \\cdots \\oplus M_n.</math>\n\nThis is another consequence of Banach's isomorphism theorem, applied to the continuous bijection from <math>M_1 \\oplus \\cdots \\oplus M_n</math> onto <math>X</math> sending <math>m_1, \\cdots, m_n</math> to the sum <math>m_1 + \\cdots + m_n.</math>\n\n:'''[[Closed graph theorem|The Closed Graph Theorem.]]''' Let <math>T : X \\to Y</math> be a linear mapping between Banach spaces. The graph of <math>T</math> is closed in <math>X \\times Y</math> if and only if <math>T</math> is continuous.\n\n {{main|Reflexive space}}\n\nThe normed space <math>X</math> is called '''[[Reflexive space|reflexive]]''' when the natural map\n<math display=block>\\begin{cases} F_X : X \\to X'' \\\\ F_X(x) (f) = f(x) & \\text{ for all } x \\in X, \\text{ and for all } f \\in X'\\end{cases}</math>\nis surjective. Reflexive normed spaces are Banach spaces.\n\n:'''Theorem.''' If <math>X</math> is a reflexive Banach space, every closed subspace of <math>X</math> and every quotient space of <math>X</math> are reflexive.\n\nThis is a consequence of the Hahn\u2013Banach theorem. \nFurther, by the open mapping theorem, if there is a bounded linear operator from the Banach space <math>X</math> onto the Banach space <math>Y,</math> then <math>Y</math> is reflexive.\n\n:'''Theorem.''' If <math>X</math> is a Banach space, then <math>X</math> is reflexive if and only if <math>X^{\\prime}</math> is reflexive.\n\n:'''Corollary.''' Let <math>X</math> be a reflexive Banach space. Then <math>X</math> is [[Separable space|separable]] if and only if <math>X^{\\prime}</math> is separable.\n\nIndeed, if the dual <math>Y^{\\prime}</math> of a Banach space <math>Y</math> is separable, then <math>Y</math> is separable. \nIf <math>X</math> is reflexive and separable, then the dual of <math>X^{\\prime}</math> is separable, so <math>X^{\\prime}</math> is separable.\n\n:'''Theorem.''' Suppose that <math>X_1, \\ldots, X_n</math> are normed spaces and that <math>X = X_1 \\oplus \\cdots \\oplus X_n.</math> Then <math>X</math> is reflexive if and only if each <math>X_j</math> is reflexive.\n\nHilbert spaces are reflexive. The <math>L^p</math> spaces are reflexive when <math>1 < p < \\infty.</math> More generally, [[uniformly convex space]]s are reflexive, by the [[Milman\u2013Pettis theorem]]. \nThe spaces <math>c_0, \\ell^1, L^1([0, 1]), C([0, 1])</math> are not reflexive. \nIn these examples of non-reflexive spaces <math>X,</math> the bidual <math>X^{\\prime\\prime}</math> is "much larger" than <math>X.</math> \nNamely, under the natural isometric embedding of <math>X</math> into <math>X^{\\prime\\prime}</math> given by the Hahn\u2013Banach theorem, the quotient <math>X^{\\prime\\prime} / X</math> is infinite-dimensional, and even nonseparable. \nHowever, Robert C. James has constructed an example<ref>{{cite journal|author = R. C. James|title=A non-reflexive Banach space isometric with its second conjugate space|journal=Proc. Natl. Acad. Sci. U.S.A.|volume=37|pages=174\u2013177|year=1951|issue=3|doi=10.1073/pnas.37.3.174| pmc=1063327|pmid=16588998|bibcode=1951PNAS...37..174J |doi-access=free}}</ref> of a non-reflexive space, usually called "''the James space''" and denoted by <math>J,</math><ref>see {{harvtxt|Lindenstrauss|Tzafriri|1977}}, p. 25.</ref> such that the quotient <math>J^{\\prime\\prime} / J</math> is one-dimensional. \nFurthermore, this space <math>J</math> is isometrically isomorphic to its bidual.\n\n:'''Theorem.''' A Banach space <math>X</math> is reflexive if and only if its unit ball is [[Compact space|compact]] in the [[weak topology]].\n\nWhen <math>X</math> is reflexive, it follows that all closed and bounded [[Convex set|convex subsets]] of <math>X</math> are weakly compact. \nIn a Hilbert space <math>H,</math> the weak compactness of the unit ball is very often used in the following way: every bounded sequence in <math>H</math> has weakly convergent subsequences.\n\nWeak compactness of the unit ball provides a tool for finding solutions in reflexive spaces to certain [[Infinite-dimensional optimization|optimization problems]]. \nFor example, every [[Convex function|convex]] continuous function on the unit ball <math>B</math> of a reflexive space attains its minimum at some point in <math>B.</math>\n\nAs a special case of the preceding result, when <math>X</math> is a reflexive space over <math>\\R,</math> every continuous linear functional <math>f</math> in <math>X^{\\prime}</math> attains its maximum <math>\\|f\\|</math> on the unit ball of <math>X.</math> \nThe following [[James' theorem|theorem of Robert C. James]] provides a converse statement.\n\n:'''James' Theorem.''' For a Banach space the following two properties are equivalent:\n:* <math>X</math> is reflexive.\n:* for all <math>f</math> in <math>X^{\\prime}</math> there exists <math>x \\in X</math> with <math>\\|x\\| \\leq 1,</math> so that <math>f(x) = \\|f\\|.</math>\n\nThe theorem can be extended to give a characterization of weakly compact convex sets.\n\nOn every non-reflexive Banach space <math>X,</math> there exist continuous linear functionals that are not ''norm-attaining''. \nHowever, the [[Errett Bishop|Bishop]]\u2013[[Robert Phelps|Phelps]] theorem<ref>{{cite journal|last1=bishop|first1=See E.|last2=Phelps|first2=R.|year=1961|title=A proof that every Banach space is subreflexive|journal=Bull. Amer. Math. Soc.|volume=67|pages=97\u201398|doi=10.1090/s0002-9904-1961-10514-4|doi-access=free }}</ref> states that norm-attaining functionals are norm dense in the dual <math>X^{\\prime}</math> of <math>X.</math>\n\n \nA sequence <math>\\left\\{ x_n \\right\\}</math> in a Banach space <math>X</math> is '''weakly convergent''' to a vector <math>x \\in X</math> if <math>\\left\\{ f\\left(x_n\\right) \\right\\}</math> converges to <math>f(x)</math> for every continuous linear functional <math>f</math> in the dual <math>X^{\\prime}.</math> The sequence <math>\\left\\{ x_n \\right\\}</math> is a '''weakly Cauchy sequence''' if <math>\\left\\{ f\\left(x_n\\right) \\right\\}</math> converges to a scalar limit <math>L(f),,</math> for every <math>f</math> in <math>X^{\\prime}.</math> \nA sequence <math>\\left\\{ f_n \\right\\}</math> in the dual <math>X^{\\prime}</math> is '''weakly* convergent''' to a functional <math>f \\in X^{\\prime}</math> if <math>f_n(x)</math> converges to <math>f(x)</math> for every <math>x</math> in <math>X.</math> \nWeakly Cauchy sequences, weakly convergent and weakly* convergent sequences are norm bounded, as a consequence of the [[Uniform boundedness principle|Banach\u2013Steinhaus]] theorem.\n\nWhen the sequence <math>\\left\\{ x_n \\right\\}</math> in <math>X</math> is a weakly Cauchy sequence, the limit <math>L</math> above defines a bounded linear functional on the dual <math>X^{\\prime},</math> that is, an element <math>L</math> of the bidual of <math>X,</math> and <math>L</math> is the limit of <math>\\left\\{ x_n \\right\\}</math> in the weak*-topology of the bidual. \nThe Banach space <math>X</math> is '''weakly sequentially complete''' if every weakly Cauchy sequence is weakly convergent in <math>X.</math> \nIt follows from the preceding discussion that reflexive spaces are weakly sequentially complete.\n\n:'''Theorem.''' <ref>see III.C.14, p. 140 in {{harvtxt|Wojtaszczyk|1991}}.</ref> For every measure <math>\\mu,</math> the space <math>L^1(\\mu)</math> is weakly sequentially complete.\n\nAn orthonormal sequence in a Hilbert space is a simple example of a weakly convergent sequence, with limit equal to the <math>\\mathbf{0}</math> vector. \nThe [[Schauder basis#Examples|unit vector basis]] of <math>\\ell^p</math> for <math>1 < p < \\infty,</math> or of <math>c_0,</math> is another example of a '''weakly null sequence''', that is, a sequence that converges weakly to <math>\\mathbf{0}.</math> \nFor every weakly null sequence in a Banach space, there exists a sequence of convex combinations of vectors from the given sequence that is norm-converging to <math>\\mathbf{0}.</math><ref>see Corollary 2, p. 11 in {{harvtxt|Diestel|1984}}.</ref>\n\nThe unit vector basis of <math>\\ell^1</math> is not weakly Cauchy. \nWeakly Cauchy sequences in <math>\\ell^1</math> are weakly convergent, since <math>L^1</math>-spaces are weakly sequentially complete. \nActually, weakly convergent sequences in <math>\\ell^1</math> are norm convergent.<ref>see p. 85 in {{harvtxt|Diestel|1984}}.</ref> This means that <math>\\ell^1</math> satisfies [[Schur's property]].\n\n \nWeakly Cauchy sequences and the <math>\\ell^1</math> basis are the opposite cases of the dichotomy established in the following deep result of H. P. Rosenthal.<ref>{{cite journal|last1=Rosenthal|first1=Haskell P|year=1974|title=A characterization of Banach spaces containing \u2113<sup>1</sup>|journal=Proc. Natl. Acad. Sci. U.S.A.|volume=71|issue=6| pages=2411\u20132413|doi=10.1073/pnas.71.6.2411|pmid=16592162|pmc=388466|arxiv=math.FA/9210205|bibcode=1974PNAS...71.2411R|doi-access=free}} Rosenthal's proof is for real scalars. The complex version of the result is due to L. Dor, in {{cite journal|last1=Dor|first1=Leonard E|year=1975|title=On sequences spanning a complex \u2113<sup>1</sup> space|journal=Proc. Amer. Math. Soc.|volume=47|pages=515\u2013516|doi=10.1090/s0002-9939-1975-0358308-x|doi-access=free}}</ref>\n\n:'''Theorem.'''<ref>see p. 201 in {{harvtxt|Diestel|1984}}.</ref> Let <math>\\left\\{x_n\\right\\}_{n \\in \\N}</math> be a bounded sequence in a Banach space. Either <math>\\left\\{ x_n \\right\\}_{n \\in \\N}</math> has a weakly Cauchy subsequence, or it admits a subsequence [[Schauder basis#Definitions|equivalent]] to the standard unit vector basis of <math>\\ell^1.</math>\n\nA complement to this result is due to Odell and Rosenthal (1975).\n\n:'''Theorem.'''<ref>{{citation|last1=Odell|first1=Edward W.|last2=Rosenthal|first2=Haskell P.|title=A double-dual characterization of separable Banach spaces containing \u2113<sup>1</sup>|journal=[[Israel Journal of Mathematics]]|volume=20|year=1975|issue=3\u20134 |pages=375\u2013384|doi=10.1007/bf02760341|doi-access=free|s2cid=122391702|url=http://dml.cz/bitstream/handle/10338.dmlcz/133414/CommentatMathUnivCarolRetro_50-2009-1_5.pdf}}.</ref> Let <math>X</math> be a separable Banach space. The following are equivalent:\n:*The space <math>X</math> does not contain a closed subspace isomorphic to <math>\\ell^1.</math>\n:*Every element of the bidual <math>X^{\\prime\\prime}</math> is the weak*-limit of a sequence <math>\\left\\{x_n\\right\\}</math> in <math>X.</math>\n\nBy the Goldstine theorem, every element of the unit ball <math>B^{\\prime\\prime}</math> of <math>X^{\\prime\\prime}</math> is weak*-limit of a net in the unit ball of <math>X.</math> When <math>X</math> does not contain <math>\\ell^1,</math> every element of <math>B^{\\prime\\prime}</math> is weak*-limit of a {{em|sequence}} in the unit ball of <math>X.</math><ref>Odell and Rosenthal, Sublemma p. 378 and Remark p. 379.</ref>\n\nWhen the Banach space <math>X</math> is separable, the unit ball of the dual <math>X^{\\prime},</math> equipped with the weak*-topology, is a metrizable compact space <math>K,</math><ref name="DualBall" /> and every element <math>x^{\\prime\\prime}</math> in the bidual <math>X^{\\prime\\prime}</math> defines a bounded function on <math>K</math>:\n<math display=block>x' \\in K \\mapsto x''(x'), \\quad \\left |x''(x')\\right| \\leq \\left \\|x''\\right \\|.</math>\n\nThis function is continuous for the compact topology of <math>K</math> if and only if <math>x^{\\prime\\prime}</math> is actually in <math>X,</math> considered as subset of <math>X^{\\prime\\prime}.</math> \nAssume in addition for the rest of the paragraph that <math>X</math> does not contain <math>\\ell^1.</math> \nBy the preceding result of Odell and Rosenthal, the function <math>x^{\\prime\\prime}</math> is the [[Pointwise convergence|pointwise limit]] on <math>K</math> of a sequence <math>\\left\\{x_n\\right\\} \\subseteq X</math> of continuous functions on <math>K,</math> it is therefore a [[Baire function|first Baire class function]] on <math>K.</math> \nThe unit ball of the bidual is a pointwise compact subset of the first Baire class on <math>K.</math><ref>for more on pointwise compact subsets of the Baire class, see {{citation|last1=Bourgain|first1=Jean|author1-link=Jean Bourgain|last2=Fremlin|first2=D. H.|last3=Talagrand |first3=Michel|title=Pointwise Compact Sets of Baire-Measurable Functions|journal=Am. J. Math.|volume=100|year=1978|issue=4|pages=845\u2013886|jstor=2373913|doi=10.2307/2373913}}.</ref>\n\n \nWhen <math>X</math> is separable, the unit ball of the dual is weak*-compact by the [[Banach\u2013Alaoglu theorem]] and metrizable for the weak* topology,<ref name="DualBall" /> hence every bounded sequence in the dual has weakly* convergent subsequences. \nThis applies to separable reflexive spaces, but more is true in this case, as stated below.\n\nThe weak topology of a Banach space <math>X</math> is metrizable if and only if <math>X</math> is finite-dimensional.<ref>see Proposition 2.5.14, p. 215 in {{harvtxt|Megginson|1998}}.</ref> If the dual <math>X^{\\prime}</math> is separable, the weak topology of the unit ball of <math>X</math> is metrizable. \nThis applies in particular to separable reflexive Banach spaces. \nAlthough the weak topology of the unit ball is not metrizable in general, one can characterize weak compactness using sequences.\n\n:'''[[Eberlein\u2013\u0160mulian theorem]]'''.<ref>see for example p. 49, II.C.3 in {{harvtxt|Wojtaszczyk|1991}}.</ref> A set <math>A</math> in a Banach space is relatively weakly compact if and only if every sequence <math>\\left\\{ a_n \\right\\}</math> in <math>A</math> has a weakly convergent subsequence.\n\nA Banach space <math>X</math> is reflexive if and only if each bounded sequence in <math>X</math> has a weakly convergent subsequence.<ref>see Corollary 2.8.9, p. 251 in {{harvtxt|Megginson|1998}}.</ref>\n\nA weakly compact subset <math>A</math> in <math>\\ell^1</math> is norm-compact. Indeed, every sequence in <math>A</math> has weakly convergent subsequences by Eberlein\u2013\u0160mulian, that are norm convergent by the Schur property of <math>\\ell^1.</math>\n\n {{main|Schauder basis}}\n\nA '''Schauder basis''' in a Banach space <math>X</math> is a sequence <math>\\left\\{ e_n \\right\\}_{n \\geq 0}</math> of vectors in <math>X</math> with the property that for every vector <math>x \\in X,</math> there exist {{em|uniquely}} defined scalars <math>\\left\\{ x_n \\right\\}_{n \\geq 0}</math> depending on <math>x,</math> such that\n<math display=block>x = \\sum_{n=0}^{\\infty} x_n e_n, \\quad \\textit{i.e.,} \\quad x = \\lim_n P_n(x), \\ P_n(x) := \\sum_{k=0}^n x_k e_k.</math>\n\nBanach spaces with a Schauder basis are necessarily [[Separable space|separable]], because the countable set of finite linear combinations with rational coefficients (say) is dense.\n\nIt follows from the Banach\u2013Steinhaus theorem that the linear mappings <math>\\left\\{P_n\\right\\}</math> are uniformly bounded by some constant <math>C.</math> \nLet <math>\\left\\{ e_n^* \\right\\}</math> denote the coordinate functionals which assign to every <math>x</math> in <math>X</math> the coordinate <math>x_n</math> of <math>x</math> in the above expansion. \nThey are called '''biorthogonal functionals'''. When the basis vectors have norm <math>1,</math> the coordinate functionals <math>\\left\\{e_n^*\\right\\}</math> have norm <math>\\,\\leq 2 C</math> in the dual of <math>X.</math>\n\nMost classical separable spaces have explicit bases. \nThe [[Haar wavelet|Haar system]] <math>\\left\\{ h_n \\right\\}</math> is a basis for <math>L^p([0, 1]), 1 \\leq p < \\infty.</math>  \nThe [[Schauder basis#Examples|trigonometric system]] is a basis in <math>L^p(\\mathbf{T})</math> when <math>1 < p < \\infty.</math> \nThe [[Haar wavelet#Haar system on the unit interval and related systems|Schauder system]] is a basis in the space <math>C([0, 1]).</math><ref>see {{harvtxt|Lindenstrauss|Tzafriri|1977}} p. 3.</ref> \nThe question of whether the disk algebra <math>A(\\mathbf{D})</math> has a basis<ref>the question appears p. 238, \u00a73 in Banach's book, {{harvtxt|Banach|1932}}.</ref> remained open for more than forty years, until Bo\u010dkarev showed in 1974 that <math>A(\\mathbf{D})</math> admits a basis constructed from the [[Haar wavelet#Haar system on the unit interval and related systems|Franklin system]].<ref>see S. V. Bo\u010dkarev, "Existence of a basis in the space of functions analytic in the disc, and some properties of Franklin's system". (Russian) Mat. Sb. (N.S.) 95(137) (1974), 3\u201318, 159.</ref>\n\nSince every vector <math>x</math> in a Banach space <math>X</math> with a basis is the limit of <math>P_n(x),</math> with <math>P_n</math> of finite rank and uniformly bounded, the space <math>X</math> satisfies the [[Approximation property|bounded approximation property]]. \nThe first example by [[Per Enflo|Enflo]] of a space failing the approximation property was at the same time the first example of a separable Banach space without a Schauder basis.<ref>see {{cite journal|last1=Enflo|first1=P.|year=1973|title=A counterexample to the approximation property in Banach spaces|journal=Acta Math.|volume=130|pages=309\u2013317|doi=10.1007/bf02392270|s2cid=120530273|doi-access=free}}</ref>\n\nRobert C. James characterized reflexivity in Banach spaces with a basis: the space <math>X</math> with a Schauder basis is reflexive if and only if the basis is both [[Schauder basis#Schauder bases and duality|shrinking and boundedly complete]].<ref>see R.C. James, "Bases and reflexivity of Banach spaces". Ann. of Math. (2) 52, (1950). 518\u2013527. See also {{harvtxt|Lindenstrauss|Tzafriri|1977}} p. 9.</ref> \nIn this case, the biorthogonal functionals form a basis of the dual of <math>X.</math>\n\n {{main|Tensor product|Topological tensor product}}\n[[File:Tensor-diagramB.jpg|thumb]]\nLet <math>X</math> and <math>Y</math> be two <math>\\mathbb{K}</math>-vector spaces. The [[tensor product]] <math>X \\otimes Y</math> of <math>X</math> and <math>Y</math> is a <math>\\mathbb{K}</math>-vector space <math>Z</math> with a bilinear mapping <math>T : X \\times Y \\to Z</math> which has the following [[universal property]]:\n\n:If <math>T_1 : X \\times Y \\to Z_1</math> is any bilinear mapping into a <math>\\mathbb{K}</math>-vector space <math>Z_1,</math> then there exists a unique linear mapping <math>f : Z \\to Z_1</math> such that <math>T_1 = f \\circ T.</math>\n\nThe image under <math>T</math> of a couple <math>(x, y)</math> in <math>X \\times Y</math> is denoted by <math>x \\otimes y,</math> and called a '''[[simple tensor]]'''. \nEvery element <math>z</math> in <math>X \\otimes Y</math> is a finite sum of such simple tensors.\n\nThere are various norms that can be placed on the tensor product of the underlying vector spaces, amongst others the [[Topological tensor product#Cross norms and tensor products of Banach spaces|projective cross norm]] and [[Topological tensor product#Cross norms and tensor products of Banach spaces|injective cross norm]] introduced by [[Alexander Grothendieck|A. Grothendieck]] in 1955.<ref>see A. Grothendieck, "Produits tensoriels topologiques et espaces nucl\u00e9aires". Mem. Amer. Math. Soc. 1955 (1955), no. 16, 140 pp., and A. Grothendieck, "R\u00e9sum\u00e9 de la th\u00e9orie m\u00e9trique des produits tensoriels topologiques". Bol. Soc. Mat. S\u00e3o Paulo 8 1953 1\u201379.</ref>\n\nIn general, the tensor product of complete spaces is not complete again. When working with Banach spaces, it is customary to say that the '''projective tensor product'''<ref>see chap. 2, p. 15 in {{harvtxt|Ryan|2002}}.</ref> of two Banach spaces <math>X</math> and <math>Y</math> is the {{em|[[Complete topological vector space|completion]]}} <math>X \\widehat{\\otimes}_\\pi Y</math> of the algebraic tensor product <math>X \\otimes Y</math> equipped with the projective tensor norm, and similarly for the '''injective tensor product'''<ref>see chap. 3, p. 45 in {{harvtxt|Ryan|2002}}.</ref> <math>X \\widehat{\\otimes}_\\varepsilon Y.</math> \nGrothendieck proved in particular that<ref>see Example. 2.19, p. 29, and pp. 49\u201350 in {{harvtxt|Ryan|2002}}.</ref>\n\n<math display=block>\\begin{align}\nC(K) \\widehat{\\otimes}_\\varepsilon Y &\\simeq C(K, Y), \\\\\nL^1([0, 1]) \\widehat{\\otimes}_\\pi Y &\\simeq L^1([0, 1], Y),\n\\end{align}</math>\n\nwhere <math>K</math> is a compact Hausdorff space, <math>C(K, Y)</math> the Banach space of continuous functions from <math>K</math> to <math>Y</math> and <math>L^1([0, 1], Y)</math> the space of Bochner-measurable and integrable functions from <math>[0, 1]</math> to <math>Y,</math> and where the isomorphisms are isometric. \nThe two isomorphisms above are the respective extensions of the map sending the tensor <math>f \\otimes y</math> to the vector-valued function <math>s \\in K \\to f(s) y \\in Y.</math>\n\n \nLet <math>X</math> be a Banach space. The tensor product <math>X' \\widehat \\otimes_\\varepsilon X</math> is identified isometrically with the closure in <math>B(X)</math> of the set of finite rank operators. \nWhen <math>X</math> has the [[approximation property]], this closure coincides with the space of [[compact operator]]s on <math>X.</math>\n\nFor every Banach space <math>Y,</math> there is a natural norm <math>1</math> linear map\n<math display=block>Y \\widehat\\otimes_\\pi X \\to Y \\widehat\\otimes_\\varepsilon X</math>\nobtained by extending the identity map of the algebraic tensor product. Grothendieck related the [[Approximation property|approximation problem]] to the question of whether this map is one-to-one when <math>Y</math> is the dual of <math>X.</math>\nPrecisely, for every Banach space <math>X,</math> the map\n<math display=block>X' \\widehat \\otimes_\\pi X \\ \\longrightarrow X' \\widehat \\otimes_\\varepsilon X</math>\nis one-to-one if and only if <math>X</math> has the approximation property.<ref>see Proposition 4.6, p. 74 in {{harvtxt|Ryan|2002}}.</ref>\n\nGrothendieck conjectured that <math>X \\widehat{\\otimes}_\\pi Y</math> and <math>X \\widehat{\\otimes}_\\varepsilon Y</math> must be different whenever <math>X</math> and <math>Y</math> are infinite-dimensional Banach spaces. \nThis was disproved by [[Gilles Pisier]] in 1983.<ref>see Pisier, Gilles (1983), "Counterexamples to a conjecture of Grothendieck", Acta Math. '''151''':181\u2013208.</ref> \nPisier constructed an infinite-dimensional Banach space <math>X</math> such that <math>X \\widehat{\\otimes}_\\pi X</math> and <math>X \\widehat{\\otimes}_\\varepsilon X</math> are equal. Furthermore, just as [[Per Enflo|Enflo's]] example, this space <math>X</math> is a "hand-made" space that fails to have the approximation property. On the other hand, Szankowski proved that the classical space <math>B\\left(\\ell^2\\right)</math> does not have the approximation property.<ref>see Szankowski, Andrzej (1981), "<math>B(H)</math> does not have the approximation property", Acta Math. '''147''': 89\u2013108. Ryan claims that this result is due to [[Per Enflo]], p. 74 in {{harvtxt|Ryan|2002}}.</ref>\n\n \n \nA necessary and sufficient condition for the norm of a Banach space <math>X</math> to be associated to an inner product is the [[parallelogram identity]]:\n\n:for all <math>x, y \\in X : \\qquad \\|x+y\\|^2 + \\|x-y\\|^2 = 2 \\left(\\|x\\|^2 + \\|y\\|^2\\right).</math>\n\nIt follows, for example, that the [[Lp space|Lebesgue space]] <math>L^p([0, 1])</math> is a Hilbert space only when <math>p = 2.</math> \nIf this identity is satisfied, the associated inner product is given by the [[polarization identity]]. In the case of real scalars, this gives:\n<math display=block>\\langle x, y\\rangle = \\tfrac{1}{4} \\left(\\|x+y\\|^2 - \\|x-y\\|^2 \\right).</math>\n\nFor complex scalars, defining the [[Inner product space|inner product]] so as to be <math>\\Complex</math>-linear in <math>x,</math> [[Antilinear map|antilinear]] in <math>y,</math> the polarization identity gives:\n<math display=block>\\langle x,y\\rangle = \\tfrac{1}{4} \\left(\\|x+y\\|^2 - \\|x-y\\|^2 + i \\left(\\|x+iy\\|^2 - \\|x-iy\\|^2\\right)\\right).</math>\n\nTo see that the parallelogram law is sufficient, one observes in the real case that <math>\\langle x, y \\rangle</math> is symmetric, and in the complex case, that it satisfies the [[Hermitian symmetry]] property and <math>\\langle i x, y \\rangle = i \\langle x, y \\rangle.</math> The parallelogram law implies that <math>\\langle x, y \\rangle</math> is additive in <math>x.</math> \nIt follows that it is linear over the rationals, thus linear by continuity.\n\nSeveral characterizations of spaces isomorphic (rather than isometric) to Hilbert spaces are available. \nThe parallelogram law can be extended to more than two vectors, and weakened by the introduction of a two-sided inequality with a constant <math>c \\geq 1</math>: Kwapie\u0144 proved that if\n<math display=block>c^{-2} \\sum_{k=1}^n \\left\\|x_k\\right\\|^2 \\leq \\operatorname{Ave}_{\\pm} \\left\\|\\sum_{k=1}^n \\pm x_k\\right\\|^2 \\leq c^2 \\sum_{k=1}^n \\left\\|x_k\\right\\|^2</math>\nfor every integer <math>n</math> and all families of vectors<math>\\left\\{ x_1, \\ldots, x_n \\right\\} \\subseteq X,</math> then the Banach space <math>X</math> is isomorphic to a Hilbert space.<ref>see Kwapie\u0144, S. (1970), "A linear topological characterization of inner-product spaces", Studia Math. '''38''':277\u2013278.</ref> \nHere, <math>\\operatorname{Ave}_{\\pm}</math> denotes the average over the <math>2^n</math> possible choices of signs <math>\\pm 1.</math>\nIn the same article, Kwapie\u0144 proved that the validity of a Banach-valued [[Parseval's theorem]] for the Fourier transform characterizes Banach spaces isomorphic to Hilbert spaces.\n\nLindenstrauss and Tzafriri proved that a Banach space in which every closed linear subspace is complemented (that is, is the range of a bounded linear projection) is isomorphic to a Hilbert space.<ref>{{cite journal\n|last1=Lindenstrauss|first1=Joram\n|last2=Tzafriri|first2=Lior\n|year=1971\n|title=On the complemented subspaces problem\n|journal=[[Israel Journal of Mathematics]]\n|volume=9\n|issue=2\n|pages=263\u2013269\n|doi=10.1007/BF02771592|doi-access=free}}</ref> The proof rests upon [[Dvoretzky's theorem]] about Euclidean sections of high-dimensional centrally symmetric convex bodies. In other words, Dvoretzky's theorem states that for every integer <math>n,</math> any finite-dimensional normed space, with dimension sufficiently large compared to <math>n,</math> contains subspaces nearly isometric to the <math>n</math>-dimensional Euclidean space.\n\nThe next result gives the solution of the so-called {{em|homogeneous space problem}}. An infinite-dimensional Banach space <math>X</math> is said to be '''homogeneous''' if it is isomorphic to all its infinite-dimensional closed subspaces. A Banach space isomorphic to <math>\\ell^2</math> is homogeneous, and Banach asked for the converse.<ref>see p. 245 in {{harvtxt|Banach|1932}}. The homogeneity property is called "propri\u00e9t\u00e9 (15)" there. Banach writes: "on ne conna\u00eet aucun exemple d'espace \u00e0 une infinit\u00e9 de dimensions qui, sans \u00eatre isomorphe avec <math>(L^2).</math> poss\u00e8de la propri\u00e9t\u00e9 (15)".</ref>\n\n:'''Theorem.'''<ref name="Gowers">Gowers, W. T. (1996), "A new dichotomy for Banach spaces", Geom. Funct. Anal. '''6''':1083\u20131093.</ref> A Banach space isomorphic to all its infinite-dimensional closed subspaces is isomorphic to a separable Hilbert space.\n\nAn infinite-dimensional Banach space is '''hereditarily indecomposable''' when no subspace of it can be isomorphic to the direct sum of two infinite-dimensional Banach spaces. \nThe [[Timothy Gowers|Gowers]] dichotomy theorem<ref name="Gowers" /> asserts that every infinite-dimensional Banach space <math>X</math> contains, either a subspace <math>Y</math> with [[Schauder basis#Unconditionality|unconditional basis]], or a hereditarily indecomposable subspace <math>Z,</math> and in particular, <math>Z</math> is not isomorphic to its closed hyperplanes.<ref>see {{cite journal|last1=Gowers|first1=W. T.|year=1994|title=A solution to Banach's hyperplane problem|journal=Bull. London Math. Soc.|volume=26|issue=6|pages=523\u2013530|doi=10.1112/blms/26.6.523}}</ref> \nIf <math>X</math> is homogeneous, it must therefore have an unconditional basis. It follows then from the partial solution obtained by Komorowski and [[Nicole Tomczak-Jaegermann|Tomczak\u2013Jaegermann]], for spaces with an unconditional basis,<ref>see {{cite journal|last1=Komorowski|first1=Ryszard A.|last2=Tomczak-Jaegermann|first2=Nicole|year=1995|title=Banach spaces without local unconditional structure|journal=[[Israel Journal of Mathematics]]|volume=89|issue=1\u20133|pages=205\u2013226|arxiv=math/9306211|doi=10.1007/bf02808201|doi-access=free|s2cid=5220304}} and also {{cite journal|last1=Komorowski|first1=Ryszard A.|last2=Tomczak-Jaegermann|first2=Nicole|year=1998|title=Erratum to: Banach spaces without local unconditional structure|journal=[[Israel Journal of Mathematics]]|volume=105|pages=85\u201392|arxiv=math/9607205|doi=10.1007/bf02780323|doi-access=free|s2cid=18565676}}</ref> that <math>X</math> is isomorphic to <math>\\ell^2.</math>\n\n \nIf <math>T : X \\to Y</math> is an [[isometry]] from the Banach space <math>X</math> onto the Banach space <math>Y</math> (where both <math>X</math> and <math>Y</math> are vector spaces over <math>\\R</math>), then the [[Mazur\u2013Ulam theorem]] states that <math>T</math> must be an affine transformation. \nIn particular, if <math>T(0_X) = 0_Y,</math> this is <math>T</math> maps the zero of <math>X</math> to the zero of <math>Y,</math> then <math>T</math> must be linear. This result implies that the metric in Banach spaces, and more generally in normed spaces, completely captures their linear structure.\n\n \nFinite dimensional Banach spaces are homeomorphic as topological spaces, if and only if they have the same dimension as real vector spaces.\n\n[[Anderson\u2013Kadec theorem]] (1965\u201366) proves<ref>{{cite book|author=C. Bessaga, A. Pe\u0142czy\u0144ski|title=Selected Topics in Infinite-Dimensional Topology|url=https://books.google.com/books?id=7n9sAAAAMAAJ|year=1975|publisher=Panstwowe wyd. naukowe|pages=177\u2013230}}</ref> that any two infinite-dimensional [[separable space|separable]] Banach spaces are homeomorphic as topological spaces. Kadec's theorem was extended by Torunczyk, who proved<ref>{{cite book|author=H. Torunczyk|title=Characterizing Hilbert Space Topology|year=1981|publisher=Fundamenta MAthematicae|pages=247\u2013262}}</ref> that any two Banach spaces are homeomorphic if and only if  they have the same [[Set-theoretic topology#Cardinal functions|density character]], the minimum cardinality of a dense subset.\n\n \nWhen two compact Hausdorff spaces <math>K_1</math> and <math>K_2</math> are [[Homeomorphism|homeomorphic]], the Banach spaces <math>C\\left(K_1\\right)</math> and <math>C\\left(K_2\\right)</math> are isometric. Conversely, when <math>K_1</math> is not homeomorphic to <math>K_2,</math> the (multiplicative) Banach\u2013Mazur distance between <math>C\\left(K_1\\right)</math> and <math>C\\left(K_2\\right)</math> must be greater than or equal to <math>2,</math> see above the [[Banach space#Examples of dual spaces|results by Amir and Cambern]]. \nAlthough uncountable compact metric spaces can have different homeomorphy types, one has the following result due to Milutin:<ref>Milyutin, Alekse\u012d A. (1966), "Isomorphism of the spaces of continuous functions over compact sets of the cardinality of the continuum". (Russian) Teor. Funkci\u012d Funkcional. Anal. i Prilo\u017een. Vyp. '''2''':150\u2013156.</ref>\n\n:'''Theorem.'''<ref>Milutin. See also Rosenthal, Haskell P., "The Banach spaces C(K)" in Handbook of the geometry of Banach spaces, Vol. 2, 1547\u20131602, North-Holland, Amsterdam, 2003.</ref> Let <math>K</math> be an uncountable compact metric space. Then <math>C(K)</math> is isomorphic to  <math>C([0, 1]).</math>\n\nThe situation is different for [[Countable set|countably infinite]] compact Hausdorff spaces. \nEvery countably infinite compact <math>K</math> is homeomorphic to some closed interval of [[ordinal number]]s\n<math display=block>\\langle 1, \\alpha \\rangle = \\{ \\gamma \\ :\\ 1 \\leq \\gamma \\leq \\alpha\\}</math>\nequipped with the [[order topology]], where <math>\\alpha</math> is a countably infinite ordinal.<ref>One can take {{math|''\u03b1'' {{=}} ''\u03c9<sup> \u03b2n</sup>''}}, where <math>\\beta + 1</math> is the [[Derived set (mathematics)#Cantor\u2013Bendixson rank|Cantor\u2013Bendixson rank]] of <math>K,</math> and <math>n > 0</math> is the finite number of points in the <math>\\beta</math>-th [[Derived set (mathematics)|derived set]] <math>K(\\beta)</math> of <math>K.</math> See [[Stefan Mazurkiewicz|Mazurkiewicz, Stefan]]; [[Wac\u0142aw Sierpi\u0144ski|Sierpi\u0144ski, Wac\u0142aw]] (1920), "Contribution \u00e0 la topologie des ensembles d\u00e9nombrables", Fundamenta Mathematicae 1: 17\u201327.</ref> \nThe Banach space <math>C(K)</math> is then isometric to {{math|''C''(<1, ''\u03b1'' >)}}. When <math>\\alpha, \\beta</math> are two countably infinite ordinals, and assuming <math>\\alpha \\leq \\beta,</math> the spaces {{math|''C''(<1, ''\u03b1'' >)}} and {{math|''C''(<1, ''\u03b2'' >)}} are isomorphic if and only if {{math|''\u03b2'' < ''\u03b1<sup>\u03c9</sup>''}}.<ref>Bessaga, Czes\u0142aw; Pe\u0142czy\u0144ski, Aleksander (1960), "Spaces of continuous functions. IV. On isomorphical classification of spaces of continuous functions", Studia Math. '''19''':53\u201362.</ref>\nFor example, the Banach spaces\n<math display=block>C(\\langle 1, \\omega\\rangle), \\ C(\\langle 1, \\omega^{\\omega} \\rangle), \\ C(\\langle 1, \\omega^{\\omega^2}\\rangle), \\ C(\\langle 1, \\omega^{\\omega^3} \\rangle), \\cdots, C(\\langle 1, \\omega^{\\omega^\\omega} \\rangle), \\cdots</math>\nare mutually non-isomorphic.\n\n \n{{main|List of Banach spaces}}\n\n{{ListOfBanachSpaces}}\n{{clear}}\n\n \nSeveral concepts of a derivative may be defined on a Banach space. See the articles on the [[Fr\u00e9chet derivative]] and the [[Gateaux derivative]] for details. \nThe Fr\u00e9chet derivative allows for an extension of the concept of a [[total derivative]] to Banach spaces. The Gateaux derivative allows for an extension of a [[directional derivative]] to [[locally convex]] [[topological vector space]]s. \nFr\u00e9chet differentiability is a stronger condition than Gateaux differentiability. \nThe [[quasi-derivative]] is another generalization of directional derivative that implies a stronger condition than Gateaux differentiability, but a weaker condition than Fr\u00e9chet differentiability.\n\n \nSeveral important spaces in functional analysis, for instance the space of all infinitely often differentiable functions <math>\\R \\to \\R,</math> or the space of all [[Distribution (mathematics)|distributions]] on <math>\\R,</math> are complete but are not normed vector spaces and hence not Banach spaces. \nIn [[Fr\u00e9chet space]]s one still has a complete [[Metric space|metric]], while [[LF-space]]s are complete [[Uniform space|uniform]] vector spaces arising as limits of Fr\u00e9chet spaces.\n\n \n* {{annotated link|Space (mathematics)}}\n** {{annotated link|Fr\u00e9chet space}}\n** {{annotated link|Hardy space}}\n** {{annotated link|Hilbert space}}\n** {{annotated link|L-semi-inner product}}\n** {{annotated link|Lp space|<math>L^p</math> space}}\n** {{annotated link|Sobolev space}}\n** {{annotated link|Banach lattice}}\n* {{annotated link|Banach manifold}}\n** {{annotated link|Banach bundle}}\n* {{annotated link|Distortion problem}}\n* {{annotated link|Interpolation space}}\n* {{annotated link|Locally convex topological vector space}}\n* {{annotated link|Smith space}}\n* {{annotated link|Topological vector space}}\n\n {{reflist|group=note}}\n\n {{reflist|30em}}\n\n \n* {{Bachman Narici Functional Analysis 2nd Edition}} <!--{{sfn|Bachman|Narici|2000|p=}}-->\n* {{Banach Th\u00e9orie des Op\u00e9rations Lin\u00e9aires}} <!-- {{sfn|Banach|1932|p=}} -->\n* {{citation|author=Beauzamy, Bernard|title=Introduction to Banach Spaces and their Geometry|year=1985|orig-year=1982|edition=Second revised|publisher=North-Holland}}.* {{Bourbaki Topological Vector Spaces}} <!-- {{sfn|Bourbaki|1987|p=}} -->\n* {{citation|last1=Bessaga|first1=C.|last2=Pe\u0142czy\u0144ski|first2=A.|title=Selected Topics in Infinite-Dimensional Topology|series=Monografie Matematyczne|publisher=Panstwowe wyd. naukowe|location=Warszawa|year=1975|url=https://books.google.com/books?id=7n9sAAAAMAAJ}}.\n* {{citation|last=Carothers|first=Neal L.|title=A short course on Banach space theory|series=London Mathematical Society Student Texts|volume=64|publisher=Cambridge University Press|location=Cambridge|year=2005|pages=xii+184|isbn=0-521-84283-2}}.\n* {{Conway A Course in Functional Analysis}} <!-- {{sfn|Conway|1990|p=}} -->\n* {{citation|last=Diestel|first=Joseph|title=Sequences and series in Banach spaces|series=Graduate Texts in Mathematics|volume=92|publisher=Springer-Verlag|location=New York|year=1984|pages=[https://archive.org/details/sequencesseriesi0000dies/page/ xii+261]|isbn=0-387-90859-5|url=https://archive.org/details/sequencesseriesi0000dies/page/ }}.\n* {{Citation|last1=Dunford|first1=Nelson|last2=Schwartz|first2=Jacob T. with the assistance of W. G. Bade and R. G. Bartle|title=Linear Operators. I. General Theory|publisher=Interscience Publishers, Inc.|location=New York|series=Pure and Applied Mathematics|volume=7|mr=0117523|year=1958}}\n* {{Edwards Functional Analysis Theory and Applications}} <!-- {{sfn|Edwards|1995|p=}} -->\n* {{Grothendieck Topological Vector Spaces}} <!-- {{sfn|Grothendieck|1973|p=}} -->\n* {{Khaleelulla Counterexamples in Topological Vector Spaces}} <!-- {{sfn|Khaleelulla|1982|p=}} -->\n* {{citation|last1=Lindenstrauss|first1=Joram|author1-link=Joram Lindenstrauss|last2=Tzafriri|first2=Lior|isbn=3-540-08072-4|location=Berlin|publisher=Springer-Verlag|series=Ergebnisse der Mathematik und ihrer Grenzgebiete|title=Classical Banach Spaces I, Sequence Spaces|volume=92|year=1977}}.\n* {{citation|last=Megginson|first=Robert E.|author-link=Robert Megginson|title=An introduction to Banach space theory|series=Graduate Texts in Mathematics|volume=183|publisher=Springer-Verlag|location=New York|year=1998|pages=xx+596|isbn=0-387-98431-3}}.\n* {{Narici Beckenstein Topological Vector Spaces|edition=2}} <!-- {{sfn|Narici|Beckenstein|2011|p=}} -->\n* {{Robertson Topological Vector Spaces}} <!-- {{sfn|Robertson|1964|p=}} -->\n* {{Rudin Walter Functional Analysis|edition=2}} <!-- {{sfn|Rudin|1991|p=}} -->\n* {{citation|last=Ryan|first=Raymond A.|year=2002|title=Introduction to Tensor Products of Banach Spaces|publisher=Springer-Verlag|series=Springer Monographs in Mathematics|location=London|isbn=1-85233-437-1|pages=xiv+225}}.\n* {{Schaefer Wolff Topological Vector Spaces|edition=2}} <!-- {{sfn|Schaefer|Wolff|1999|p=}} -->\n* {{Swartz An Introduction to Functional Analysis}} <!-- {{sfn|Swartz|1992|p=}} -->\n* {{Tr\u00e8ves Fran\u00e7ois Topological vector spaces, distributions and kernels}} <!-- {{sfn|Tr\u00e8ves|2006|p=}} -->\n* {{Wilansky Modern Methods in Topological Vector Spaces}} <!-- {{sfn|Wilansky|2013|p=}} -->\n* {{citation|last=Wojtaszczyk|first=Przemys\u0142aw|title=Banach spaces for analysts|series=Cambridge Studies in Advanced Mathematics|volume=25|publisher=Cambridge University Press|location=Cambridge|year=1991|pages=xiv+382|isbn=0-521-35618-0}}.\n\n \n{{Commons category|Banach spaces}}\n* {{springer|title=Banach space|id=p/b015190}}\n* {{MathWorld|BanachSpace|Banach Space}}\n\n{{Banach spaces}}\n{{Functional Analysis}}\n{{Authority control}}"}},
{"article_title": "Bacterial conjugation", "pageid": "4460", "revid": "1061045670", "timestamp": "2021-12-19T08:47:56Z", "history_paths": [["Bacterial conjugation --- Introduction ---", "History"]], "categories": ["antimicrobial resistance", "bacteriology", "biotechnology", "modification of genetic information", "molecular biology"], "heading_tree": {"Bacterial conjugation --- Introduction ---": {"History": {}, "Mechanism": {}, "Conjugal transfer in mycobacteria": {}, "Inter-kingdom transfer": {}, "Genetic engineering applications": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Bacterial conjugation --- Introduction ---|History": "The process was discovered by [[Joshua Lederberg]] and [[Edward Tatum]]<ref>{{cite journal | vauthors = Lederberg J, Tatum EL | title = Gene recombination in ''E. coli'' | journal = Nature | year = 1946 | volume = 158 | pages = 558 | doi = 10.1038/158558a0 | pmid = 21001945 | issue = 4016 | bibcode = 1946Natur.158..558L | s2cid = 1826960 }}</ref> in 1946."}},
{"article_title": "BIOS", "pageid": "4473", "revid": "1062905929", "timestamp": "2021-12-31T02:55:53Z", "history_paths": [["BIOS --- Introduction ---", "History"]], "categories": ["bios", "cp/m technology", "dos technology", "windows technology"], "heading_tree": {"BIOS --- Introduction ---": {"History": {}, "{{Anchor|BCU}}User interface": {}, "Operation": {"System startup": {}, "Boot process": {"Boot priority": {}, "Boot failure": {}}, "Boot environment": {}}, "Extensions (option ROMs)": {"Boot procedure": {}, "Initialization": {}, "Physical placement": {}}, "Operating system services": {"Processor microcode updates": {}, "{{Anchor|SLIC}}Identification": {}, "Overclocking": {}, "Modern use": {}}, "Configuration": {"Setup utility": {}, "Hardware monitoring": {}, "{{anchor|Flashing the BIOS}}Reprogramming": {}}, "Hardware": {}, "{{Anchor|COMPARISON}}Vendors and products": {}, "{{Anchor|MEBROMI}}Security": {}, "Alternatives and successors": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"BIOS --- Introduction ---|History": "{{rquote|right|\n<pre>/* C P / M   B A S I C   I / O    S Y S T E M    (B I O S)\n                    COPYRIGHT (C) GARY A. KILDALL\n                             JUNE, 1975 */\n[\u2026]\n/*  B A S I C   D I S K    O P E R A T I N G   S Y S T E M  (B D O S)\n                    COPYRIGHT (C) GARY A. KILDALL\n                            JUNE, 1975 */</pre>\n<!-- some whitespace removed from original citation -->\n| An excerpt from the BDOS.PLM file header in the [[PL/M]] source code of CP/M 1.1 or 1.2 for [[Lawrence Livermore Laboratories]] (LLL)<ref name="Kildall_1975_BDOS"/>\n}}\n\nThe term BIOS (Basic Input/Output System) was created by [[Gary Kildall]]<ref name="Swaine_1997_Entrepreneurship" /><ref name="IEEE_2014_BIOS"/> and first appeared in the [[CP/M]] operating system in 1975,<ref name="Kildall_1975_BDOS" /><ref name="Kildall_1980_CPM" /><ref name="IEEE_2014_BIOS"/><ref name="Shustek_2016"/><ref name="Fischer_2001_Ewing" /><ref name="Fraley_2007_Killian" /> describing the machine-specific part of CP/M loaded during boot time that interfaces directly with the [[computer hardware|hardware]].<ref name="Kildall_1980_CPM" /> (A CP/M machine usually has only a simple [[boot loader]] in its ROM.)\n\nVersions of [[MS-DOS]], [[PC DOS]] or [[DR-DOS]] contain a file called variously "[[IO.SYS]]", "[[IBMBIO.COM]]", "IBMBIO.SYS", or "DRBIOS.SYS"; this file is known as the "DOS BIOS" (also known as the "DOS I/O System") and contains the lower-level hardware-specific part of the operating system. Together with the underlying hardware-specific but operating system-independent "System BIOS", which resides in [[Read-only memory|ROM]], it represents the analogue to the "[[CP/M BIOS]]".\n\nThe BIOS originally [[Proprietary software|proprietary]] to the [[IBM PC]] has been [[reverse engineer]]ed by some companies (such as [[Phoenix Technologies]]) looking to create compatible systems.\n\nWith the introduction of PS/2 machines, IBM divided the System BIOS into real- and protected-mode portions. The real-mode portion was meant to provide backward compatibility with existing operating systems such as DOS, and therefore was named "CBIOS" (for "Compatibility BIOS"), whereas the "ABIOS" (for "Advanced BIOS") provided new interfaces specifically suited for multitasking operating systems such as [[OS/2]].<ref>{{cite journal |title=The IBM PC BIOS |journal=Byte |year=1989 |last=Glass |first=Brett |pages=303-310 |url=https://archive.org/details/eu_BYTE-1989-04_OCR/page/n373/mode/2up?view=theater |accessdate=2021-12-31 }}</ref>"}},
{"article_title": "Biotechnology", "pageid": "4502", "revid": "1062527806", "timestamp": "2021-12-29T00:51:57Z", "history_paths": [["Biotechnology --- Introduction ---", "History"]], "categories": ["biotechnology", "life sciences industry"], "heading_tree": {"Biotechnology --- Introduction ---": {"Definition": {}, "History": {}, "Examples": {"Medicine": {}, "Agriculture": {}, "{{visible anchor|Industrial|Industrial biotechnology}}": {}, "Environmental": {}, "Regulation": {}}, "Learning": {}, "References and notes": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Biotechnology --- Introduction ---|History": "[[File:The Brewer designed and engraved in the Sixteenth. Century by J Amman.png|upright|thumb|[[Brewing]] was an early application of biotechnology.]]\n\n{{Main|History of biotechnology}}\n\nAlthough not normally what first comes to mind, many forms of human-derived [[agriculture]] clearly fit the broad definition of "'utilizing a biotechnological system to make products". Indeed, the cultivation of plants may be viewed as the earliest biotechnological enterprise.\n\n[[Agriculture]] has been theorized to have become the dominant way of producing food since the [[Neolithic Revolution]]. Through early biotechnology, the earliest farmers selected and bred the best-suited crops, having the highest yields, to produce enough food to support a growing population. As crops and fields became increasingly large and difficult to maintain, it was discovered that specific organisms and their by-products could effectively [[fertilize]], [[nitrogen fixation|restore nitrogen]], and [[pesticide|control pests]]. Throughout the history of agriculture, farmers have inadvertently altered the genetics of their crops through introducing them to new environments and [[plant breeding|breeding]] them with other plants \u2014 one of the first forms of biotechnology.\n\nThese processes also were included in early [[Fermentation (biochemistry)|fermentation]] of [[beer]].<ref>See {{Cite book |last=Arnold |first=John P. |title=Origin and History of Beer and Brewing: From Prehistoric Times to the Beginning of Brewing Science and Technology |publisher=BeerBooks |year=2005 |isbn=978-0-9662084-1-2 |location=Cleveland, Ohio |page=34 |oclc=71834130 |name-list-style=vanc}}.</ref> These processes were introduced in early [[Mesopotamia]], [[Egypt]], [[China]] and [[India]], and still use the same basic biological methods.  In [[brewing]], malted grains (containing [[enzyme]]s) convert starch from grains into sugar and then adding specific [[yeast]]s to produce beer. In this process, [[carbohydrate]]s in the grains broke down into alcohols, such as ethanol. Later, other cultures produced the process of [[lactic acid fermentation]], which produced other preserved foods, such as [[soy sauce]]. Fermentation was also used in this time period to produce [[leavened bread]]. Although the process of fermentation was not fully understood until [[Louis Pasteur]]'s work in 1857, it is still the first use of biotechnology to convert a food source into another form.\n\nBefore the time of [[Charles Darwin]]'s work and life, animal and plant scientists had already used selective breeding. Darwin added to that body of work with his scientific observations about the ability of science to change species. These accounts contributed to Darwin's theory of natural selection.<ref>{{Cite journal |last=Cole-Turner |first=Ronald |date=2003 |title=Biotechnology |url=http://www.encyclopedia.com/doc/1G2-3404200058.html |journal=Encyclopedia of Science and Religion |access-date=December 7, 2014 |name-list-style=vanc}}</ref>\n\nFor thousands of years, humans have used selective breeding to improve the production of crops and livestock to use them for food. In selective breeding, organisms with desirable characteristics are mated to produce offspring with the same characteristics. For example, this technique was used with corn to produce the largest and sweetest crops.<ref name="Thieman">{{Cite book |title=Introduction to Biotechnology |vauthors=Thieman WJ, Palladino MA |publisher=Pearson/Benjamin Cummings |year=2008 |isbn=978-0-321-49145-9}}</ref>\n\nIn the early twentieth century scientists gained a greater understanding of [[microbiology]] and explored ways of manufacturing specific products. In 1917, [[Chaim Weizmann]] first used a pure microbiological culture in an industrial process, that of manufacturing [[corn starch]] using ''[[Clostridium acetobutylicum]],'' to produce [[acetone]], which the [[United Kingdom]] desperately needed to manufacture [[explosive]]s during [[World War I]].<ref name="Springham_biotechnology">{{Cite book |url=https://books.google.com/books?id=9GY5DCr6LD4C |title=Biotechnology: The Science and the Business |vauthors=Springham D, Springham G, Moses V, Cape RE |publisher=CRC Press |year=1999 |isbn=978-90-5702-407-8 |page=1}}</ref>\n\nBiotechnology has also led to the development of antibiotics. In 1928, [[Alexander Fleming]] discovered the mold ''[[Penicillium]]''. His work led to the purification of the antibiotic compound formed by the mold by Howard Florey, Ernst Boris Chain and Norman Heatley \u2013 to form what we today know as [[penicillin]]. In 1940, penicillin became available for medicinal use to treat bacterial infections in humans.<ref name=Thieman/>\n\nThe field of modern biotechnology is generally thought of as having been born in 1971 when Paul Berg's (Stanford) experiments in gene splicing had early success. [[Herbert Boyer|Herbert W. Boyer]] (Univ. Calif. at San Francisco) and [[Stanley Norman Cohen|Stanley N. Cohen]] (Stanford) significantly advanced the new technology in 1972 by transferring genetic material into a bacterium, such that the imported material would be reproduced. The commercial viability of a biotechnology industry was significantly expanded on June 16, 1980, when the [[United States Supreme Court]] ruled that a [[genetic engineering|genetically modified]] [[microorganism]] could be [[patent]]ed in the case of ''[[Diamond v. Chakrabarty]]''.<ref name="DiamondvChakrabarty">"[http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=us&vol=447&invol=303 Diamond v. Chakrabarty, 447 U.S. 303 (1980). No. 79-139]." ''[[United States Supreme Court]].'' June 16, 1980. Retrieved on May 4, 2007.</ref> Indian-born [[Ananda Mohan Chakrabarty|Ananda Chakrabarty]], working for [[General Electric]], had modified a bacterium (of the genus ''[[Pseudomonas]]'') capable of breaking down crude oil, which he proposed to use in treating oil spills. (Chakrabarty's work did not involve gene manipulation but rather the transfer of entire organelles between strains of the ''Pseudomonas'' bacterium.\n\nThe [[MOSFET]] (metal-oxide-semiconductor field-effect transistor) was invented by [[Mohamed M. Atalla]] and [[Dawon Kahng]] in 1959.<ref name="computerhistory">{{Cite journal |title=1960: Metal Oxide Semiconductor (MOS) Transistor Demonstrated |url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/ |journal=The Silicon Engine: A Timeline of Semiconductors in Computers |publisher=[[Computer History Museum]] |access-date=August 31, 2019}}</ref> Two years later, [[Leland C. Clark]] and Champ Lyons invented the first [[biosensor]] in 1962.<ref name="Park">{{Cite journal |last1=Park |first1=Jeho |last2=Nguyen |first2=Hoang Hiep |last3=Woubit |first3=Abdela |last4=Kim |first4=Moonil |s2cid=55557610 |date=2014 |title=Applications of Field-Effect Transistor (FET){{ndash}}Type Biosensors |journal=Applied Science and Convergence Technology |volume=23 |issue=2 |pages=61\u201371 |doi=10.5757/ASCT.2014.23.2.61 |issn=2288-6559|doi-access=free }}</ref><ref>{{Cite journal |last1=Clark |first1=Leland C. |last2=Lyons |first2=Champ |date=1962 |title=Electrode Systems for Continuous Monitoring in Cardiovascular Surgery |journal=Annals of the New York Academy of Sciences |volume=102 |issue=1 |pages=29\u201345 |bibcode=1962NYASA.102...29C |doi=10.1111/j.1749-6632.1962.tb13623.x |issn=1749-6632 |pmid=14021529 |s2cid=33342483 |author1-link=Leland Clark}}</ref> [[Bio-FET|Biosensor MOSFETs]] were later developed, and they have since been widely used to measure [[physics|physical]], [[chemistry|chemical]], [[biological]] and [[environmental]] parameters.<ref name="Bergveld">{{Cite journal |last=Bergveld |first=Piet |date=October 1985 |title=The impact of MOSFET-based sensors |url=https://core.ac.uk/download/pdf/11473091.pdf |journal=Sensors and Actuators |volume=8 |issue=2 |pages=109\u2013127 |bibcode=1985SeAc....8..109B |doi=10.1016/0250-6874(85)87009-8 |issn=0250-6874 |author1-link=Piet Bergveld}}</ref> The first BioFET was the [[ion-sensitive field-effect transistor]] (ISFET), invented by [[Piet Bergveld]] in 1970.<ref>{{Cite journal |last1=Chris Toumazou |last2=Pantelis Georgiou |date=December 2011 |title=40 years of ISFET technology:From neuronal sensing to DNA sequencing |url=https://www.researchgate.net/publication/260616066 |journal=[[Electronics Letters]] |access-date=May 13, 2016}}</ref><ref name="Bergveld1970">{{Cite journal |last=Bergveld |first=P. |date=January 1970 |title=Development of an Ion-Sensitive Solid-State Device for Neurophysiological Measurements |journal=[[IEEE Transactions on Biomedical Engineering]] |volume=BME-17 |issue=1 |pages=70\u201371 |doi=10.1109/TBME.1970.4502688 |pmid=5441220}}</ref> It is a special type of MOSFET,<ref name="Bergveld" /> where the [[metal gate]] is replaced by an [[ion]]-sensitive [[membrane]], [[electrolyte]] solution and [[reference electrode]].<ref name="Schoning">{{Cite journal |last1=Sch\u00f6ning |first1=Michael J. |last2=Poghossian |first2=Arshak |date=September 10, 2002 |title=Recent advances in biologically sensitive field-effect transistors (BioFETs) |url=http://juser.fz-juelich.de/record/16078/files/12968.pdf |journal=Analyst |volume=127 |issue=9 |pages=1137\u20131151 |bibcode=2002Ana...127.1137S |doi=10.1039/B204444G |issn=1364-5528 |pmid=12375833}}</ref> The ISFET is widely used in [[biomedical]] applications, such as the detection of [[DNA hybridization]], [[biomarker]] detection from [[blood]], [[antibody]] detection, [[glucose]] measurement, [[pH]] sensing, and [[genetic technology]].<ref name="Schoning" />\n\nBy the mid-1980s, other BioFETs had been developed, including the [[gas sensor]] FET (GASFET), [[pressure sensor]] FET (PRESSFET), [[chemical field-effect transistor]] (ChemFET), [[ISFET|reference ISFET]] (REFET), enzyme-modified FET (ENFET) and immunologically modified FET (IMFET).<ref name="Bergveld" /> By the early 2000s, BioFETs such as the [[DNA field-effect transistor]] (DNAFET), [[Genetically modified|gene-modified]] FET (GenFET) and [[Membrane potential|cell-potential]] BioFET (CPFET) had been developed.<ref name="Schoning" />\n\nA factor influencing the biotechnology sector's success is improved intellectual property rights legislation\u2014and enforcement\u2014worldwide, as well as strengthened demand for medical and pharmaceutical products to cope with an ageing, and ailing, [[United States|U.S.]] population.<ref>[https://web.archive.org/web/20080402034432/http://www.ibisworld.com/pressrelease/pressrelease.aspx?prid=115 VoIP Providers And Corn Farmers Can Expect To Have Bumper Years In 2008 And Beyond, According To The Latest Research Released By Business Information Analysts At IBISWorld]. Los Angeles (March 19, 2008)</ref>\n\nRising demand for biofuels is expected to be good news for the biotechnology sector, with the [[United States Department of Energy|Department of Energy]] estimating [[ethanol]] usage could reduce U.S. petroleum-derived fuel consumption by up to 30% by 2030. The biotechnology sector has allowed the U.S. farming industry to rapidly increase its supply of corn and soybeans\u2014the main inputs into biofuels\u2014by developing genetically modified seeds that resist pests and drought. By increasing farm productivity, biotechnology boosts biofuel production.<ref>{{Cite web |url=http://www.bio-medicine.org/biology-technology-1/The-Recession-List---Top-10-Industries-to-Fly-and-Flop-in-2008-4076-3/ |title=The Recession List - Top 10 Industries to Fly and Flop in 2008 |date=2008-03-19 |publisher=Bio-Medicine.org |access-date=May 19, 2008 |archive-date=June 2, 2008 |archive-url=https://web.archive.org/web/20080602160516/http://www.bio-medicine.org/biology-technology-1/The-Recession-List---Top-10-Industries-to-Fly-and-Flop-in-2008-4076-3/ |url-status=dead }}</ref>"}},
{"article_title": "Carbon nanotube", "pageid": "5320", "revid": "1061725212", "timestamp": "2021-12-23T14:49:56Z", "history_paths": [["Carbon nanotube --- Introduction ---", "History"]], "categories": ["allotropes of carbon", "carbon nanotubes", "emerging technologies", "transparent electrodes", "refractory materials", "space elevator"], "heading_tree": {"Carbon nanotube --- Introduction ---": {"Structure of single-walled tubes {{anchor|Structure}}": {"The zigzag and armchair configurations": {}, "The (''n'',''m'') notation": {}, "Nanotube types": {}, "Chirality and mirror symmetry": {}, "Circumference and diameter": {}}, "Physical limits": {"Narrowest nanotubes": {}, "Length": {}, "Density": {}}, "Variants": {"Multi-walled": {}, "Junctions and crosslinking": {}, "Other morphologies": {}}, "Properties": {"Mechanical": {}, "Electrical": {}, "Optical": {}, "Thermal": {}}, "Synthesis": {}, "Functionalization": {}, "Modeling": {}, "Metrology": {}, "Chemical modification": {}, "Applications": {"Current": {}, "Under development": {}, "Potential": {}}, "Safety and health": {}, "History": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Carbon nanotube --- Introduction ---|History": "{{See also|Timeline of carbon nanotubes|Fullerene#History}}\nThe true identity of the discoverers of carbon nanotubes is a subject of some controversy.<ref name="carbon1">{{cite book|title=Carbon Nanotubes as Platforms for Biosensors with Electrochemical and Electronic Transduction|first=Merc\u00e8|last=Pacios Pujad\u00f3|publisher=Springer Heidelberg|year=2012|pages=xx, 208|doi=10.1007/978-3-642-31421-6|isbn=978-3-642-31421-6|series=Springer Theses|hdl=10803/84001|url=http://ddd.uab.cat/record/101063}}</ref> A 2006 editorial written by Marc Monthioux and Vladimir Kuznetsov in the journal ''Carbon'' described the origin of the carbon nanotube.<ref name="carbon">{{cite journal |last1=Monthioux |first1=Marc |last2=Kuznetsov |first2=Vladimir L. |title=Who should be given the credit for the discovery of carbon nanotubes? |journal=Carbon |date=August 2006 |volume=44 |issue=9 |pages=1621\u20131623 |doi=10.1016/j.carbon.2006.03.019 |url=https://nanotube.msu.edu/HSS/2006/1/2006-1.pdf }}</ref> A large percentage of academic and popular literature attributes the discovery of hollow, nanometer-size tubes composed of graphitic carbon to [[Sumio Iijima]] of [[NEC]] in 1991. His paper initiated a flurry of excitement and could be credited with inspiring the many scientists now studying applications of carbon nanotubes. Though Iijima has been given much of the credit for discovering carbon nanotubes, it turns out that the timeline of carbon nanotubes goes back much further than 1991.<ref name="carbon1" />\n\nIn 1952, L. V. Radushkevich and V. M. Lukyanovich published clear images of 50 nanometer diameter tubes made of carbon in the ''Journal of Physical Chemistry Of Russia''.<ref name="CVD"/> This discovery was largely unnoticed, as the article was published in Russian, and Western scientists' access to Soviet press was limited during the [[Cold War]]. Monthioux and Kuznetsov mentioned in their ''Carbon'' editorial:<ref name="carbon" /> {{quote|text=The fact is, Radushkevich and Lukyanovich [...] should be credited for the discovery that carbon filaments could be hollow and have a nanometer- size diameter, that is to say for the discovery of carbon nanotubes.}}\n\nIn 1976, [[Morinobu Endo]] of [[Centre national de la recherche scientifique|CNRS]] observed hollow tubes of rolled up graphite sheets synthesised by a chemical vapour-growth technique.<ref name="endo1"/> The first specimens observed would later come to be known as single-walled carbon nanotubes (SWNTs).<ref name="carbon2">{{cite report|title=WTEC Panel Report on 'International Assessment of Research and Development of Carbon Nanotube Manufacturing and Applications' Final Report|author=Eklund, Peter C.|publisher=World Technology Evaluation Center (WTEC)|year=2007|url=http://www.wtec.org/cnm/CNM_final_report.pdf|access-date=5 August 2015|archive-url=https://web.archive.org/web/20170311174000/http://www.wtec.org/cnm/CNM_final_report.pdf|archive-date=11 March 2017|url-status=dead}}</ref> Endo, in his early review of vapor-phase-grown carbon fibers (VPCF), also reminded us that he had observed a hollow tube, linearly extended with parallel carbon layer faces near the fiber core.<ref>{{cite journal |last1=Oberlin |first1=A. |last2=Endo |first2=M. |last3=Koyama |first3=T. |title=Filamentous growth of carbon through benzene decomposition |journal=Journal of Crystal Growth |date=March 1976 |volume=32 |issue=3 |pages=335\u2013349 |doi=10.1016/0022-0248(76)90115-9 |bibcode=1976JCrGr..32..335O |url=http://www.kroto.info/wp-content/uploads/2015/10/1.M.ENdoJCrystalGrowth1976.pdf }}</ref> This appears to be the observation of multi-walled carbon nanotubes at the center of the fiber.<ref name="carbon2" /> The mass-produced MWCNTs today are strongly related to the VPGCF developed by Endo.<ref name="carbon2" /> In fact, they call it the "Endo-process", out of respect for his early work and patents.<ref name="carbon2" /><ref>Koyama, T. and Endo, M.T. (1983) "Method for Manufacturing Carbon Fibers by a Vapor Phase Process," Japanese Patent, 1982-58, 966.</ref>\n\nIn 1979, John Abrahamson presented evidence of carbon nanotubes at the 14th Biennial Conference of Carbon at [[Pennsylvania State University]]. The conference paper described carbon nanotubes as carbon fibers that were produced on carbon anodes during arc discharge. A characterization of these fibers was given, as well as hypotheses for their growth in a nitrogen atmosphere at low pressures.<ref>{{cite journal |last1=Abrahamson |first1=John |last2=Wiles |first2=Peter G. |last3=Rhoades |first3=Brian L |title=Structure of carbon fibres found on carbon arc anodes |journal=Carbon |date=January 1999 |volume=37 |issue=11 |pages=1873\u20131874 |doi=10.1016/S0008-6223(99)00199-2 }}</ref>\n\nIn 1981, a group of Soviet scientists published the results of chemical and structural characterization of carbon nanoparticles produced by a thermocatalytical disproportionation of carbon monoxide. Using TEM images and [[X-ray scattering techniques|XRD]] patterns, the authors suggested that their "carbon multi-layer tubular crystals" were formed by rolling graphene layers into cylinders. They speculated that via this rolling, many different arrangements of graphene hexagonal nets are possible. They suggested two such possible arrangements: circular arrangement (armchair nanotube); and a spiral, helical arrangement (chiral tube).<ref>Izvestiya Akademii Nauk SSSR, Metals. 1982, #3, pp. 12\u201317 (in Russian){{full citation needed|missing title and author|date=October 2021}}</ref>\n\nIn 1987, Howard G. Tennent of Hyperion Catalysis was issued a U.S. patent for the production of "cylindrical discrete carbon fibrils" with a "constant diameter between about 3.5 and about 70 nanometers..., length 10<sup>2</sup> times the diameter, and an outer region of multiple essentially continuous layers of ordered carbon atoms and a distinct inner core...."<ref>{{Ref patent|country=US|number=4663230|title=Carbon fibrils, method for producing same and compositions containing same|gdate=1987-05-05|fdate=1984-12-06|invent1=Tennent, Howard G.}}</ref>\n\nHelping to create the initial excitement associated with carbon nanotubes were Iijima's 1991 discovery of multi-walled carbon nanotubes in the insoluble material of arc-burned graphite rods;<ref name=Iijima1/> and Mintmire, Dunlap, and White's independent prediction that if single-walled carbon nanotubes could be made, they would exhibit remarkable conducting properties.<ref name=mintmire1/> Nanotube research accelerated greatly following the independent discoveries<ref name=Iijima2/><ref name=Bethune/> by Iijima and Ichihashi at NEC, and Bethune ''et al.'' at IBM, of ''single-walled'' carbon nanotubes, and methods to specifically produce them by adding transition-metal catalysts to the carbon in an arc discharge. The arc discharge technique was well known to produce the famed Buckminster fullerene {{clarify span |on a preparative scale |date=May 2021}},<ref name="Kratschmer-C60">{{cite journal|first1=W.|last1=Kr\u00e4tschmer|year=1990|title=Solid C60: a new form of carbon|journal=Nature|volume=347|pages=354\u2013358|doi=10.1038/347354a0|last2=Lamb|first2=Lowell D.|last3=Fostiropoulos|first3=K.|last4=Huffman|first4=Donald R.|issue=6291|bibcode = 1990Natur.347..354K|s2cid=4359360}}</ref> and these results appeared to extend the run of accidental discoveries relating to fullerenes. The discovery of nanotubes remains a contentious issue. Many believe that Iijima's report in 1991 is of particular importance because it brought carbon nanotubes into the awareness of the scientific community as a whole.<ref name="carbon1" /><ref name="carbon2" />\n\nIn 2020, during archaeological excavation of [[Keezhadi]] in [[Tamil Nadu]], [[India]], ~2500-year-old pottery was discovered whose coatings appear to contain carbon nanotubes.  The robust mechanical properties of the nanotubes are partially why the coatings have lasted for so many years, say the scientists.<ref>{{cite journal |last1=Kokarneswaran |first1=Manivannan |last2=Selvaraj |first2=Prakash |last3=Ashokan |first3=Thennarasan |last4=Perumal |first4=Suresh |last5=Sellappan |first5=Pathikumar |last6=Murugan |first6=Kandhasamy Durai |last7=Ramalingam |first7=Sivanantham |last8=Mohan |first8=Nagaboopathy |last9=Chandrasekaran |first9=Vijayanand |title=Discovery of carbon nanotubes in sixth century BC potteries from Keeladi, India |journal=Scientific Reports |date=13 November 2020 |volume=10 |issue=1 |pages=19786 |doi=10.1038/s41598-020-76720-z |pmid=33188244 |pmc=7666134 |bibcode=2020NatSR..1019786K }}</ref>"}},
{"article_title": "Clarke's three laws", "pageid": "5653", "revid": "1060947011", "timestamp": "2021-12-18T17:36:54Z", "history_paths": [["Clarke's three laws --- Introduction ---", "Origins"]], "categories": ["adages", "arthur c. clarke", "technology folklore", "technology forecasting", "principles"], "heading_tree": {"Clarke's three laws --- Introduction ---": {"The laws": {}, "Origins": {}, "Variants of the third law": {}, "Corollaries": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Clarke's three laws --- Introduction ---|Origins": "One account claimed that Clarke's "laws" were developed after the editor of his works in French started numbering the author's assertions.<ref>{{Cite book |title= The Quote Verifier: Who Said What, Where, and When |last= Keyes |first= Ralph |publisher= St. Martin's Press |year= 2006 |isbn= 978-0-31234004-9 |location= New York |page= [https://archive.org/details/quoteverifierwho00keye/page/217 217] |url= https://archive.org/details/quoteverifierwho00keye/page/217 }}</ref>  All three laws appear in Clarke's essay "Hazards of Prophecy: The Failure of Imagination", first published in ''Profiles of the Future'' (1962).<ref>"Hazards of Prophecy: The Failure of Imagination" in the collection ''Profiles of the Future: An Enquiry into the Limits of the Possible'' (1962, rev. 1973), pp. 14, 21, 36.</ref> However, they were not all published at the same time. Clarke's first law was proposed in the 1962 edition of the essay, as "Clarke's Law" in ''Profiles of the Future''.\n\nThe second law is offered as a simple observation in the same essay but its status as Clarke's second law was conferred by others. It was initially a derivative of the first law and formally became Clarke's second law where the author proposed the third law in the 1973 revision of ''Profiles of the Future'', which included an acknowledgement.<ref>{{Cite book |title= The Believing Brain: From Ghosts and Gods to Politics and Conspiracies \u2014 How We Construct Beliefs and Reinforce Them as Truths |last= Shermer |first= Michael |author-link= Michael Shermer |publisher= Henry Holt & Co. |year= 2011 |isbn= 978-0-80509125-0 |location= New York |page= [https://archive.org/details/believingbrainfr0000sher/page/358 358] |url= https://archive.org/details/believingbrainfr0000sher/page/358 }}</ref> It was also here that Clarke wrote about the third law in these words: "As three laws were good enough for [[Isaac Newton|Newton]], I have modestly decided to stop there".\n\nThe third law is the best known and most widely cited. It was published in a 1968 letter to ''[[Science (journal)|Science]]'' magazine<ref>{{Cite journal|last=Clarke|first=Arthur C.|date=1968-01-19|title=Clarke's Third Law on UFO's|url=https://science.sciencemag.org/content/159/3812/255.3|journal=Science|language=en|volume=159|issue=3812|pages=255|doi=10.1126/science.159.3812.255-b|issn=0036-8075}}</ref> and eventually added to the 1973 revision of the "Hazards of Prophecy" essay.<ref>{{Cite book |title=Profiles of the Future: An Inquiry into the Limits of the Possible |last=Clarke |first= Arthur C.|publisher= Popular Library |year=1973 |isbn= 978-0-33023619-5}}</ref> In 1952, Isaac Asimov in his book ''Foundation and Empire'' (part 1.1 ''Search for Magicians'') wrote down a similar phrase "... an uninformed public tends to confuse scholarship with magicians..."<ref>{{Cite book|last=Asimov|first=Isaac|title=Foundation and Empire|publisher=Bantam Dell, A Division of Random House, Inc.|year=1952|isbn=0-553-29337-0|location=New York|pages=10}}</ref> It also echoes a statement in a 1942 story by [[Leigh Brackett]]: "Witchcraft to the ignorant, \u2026 simple science to the learned".<ref>"The Sorcerer of Rhiannon", ''[[Astounding]]'' February 1942, p. 39.</ref> Even earlier examples of this sentiment may be found in ''[[Wild Talents (book)|Wild Talents]]'' (1932) by [[Charles Fort]]: "\u2026a performance that may someday be considered understandable, but that, in these primitive times, so transcends what is said to be the known that it is what I mean by magic," and in the short story ''[[The Hound of Death]]'' (1933) by [[Agatha Christie]]: "The supernatural is only the nature of which the laws are not yet understood." [[Virginia Woolf]]'s 1928 novel ''[[Orlando: A Biography]]'' explicitly compares advanced technology to magic:\n\n{{Blockquote\n| text   = Then she got into the lift, for the good reason that the door stood open; and was shot smoothly upwards. The very fabric of life now, she thought as she rose, is magic. In the eighteenth century, we knew how everything was done; but here I rise through the air; I listen to voices in America; I see men flying \u2013 but how it's done I can't even begin to wonder. So my belief in magic returns.\n}}\n\nClarke gave an example of the third law when he said that while he "would have believed anyone who told him back in 1962 that there would one day exist a book-sized object capable of holding the content of an entire library, he would never have accepted that the same device could find a page or word in a second and then convert it into any typeface and size from [[Albertus (typeface)|Albertus]] Extra Bold to [[Univers|Zurich]] [[Calligraphic]]", referring to his memory of "seeing and hearing [[Linotype machine]]s which slowly converted 'molten lead into front pages that required two men to lift them'".<ref name= "Gooden2015"/>"}},
{"article_title": "Cathode-ray tube", "pageid": "6014", "revid": "1063073466", "timestamp": "2022-01-01T02:04:14Z", "history_paths": [["Cathode-ray tube --- Introduction ---", "History"]], "categories": ["cathode ray tube", "consumer electronics", "display technology", "television technology", "vacuum tube displays", "audiovisual introductions in 1897", "telecommunications-related introductions in 1897"], "heading_tree": {"Cathode-ray tube --- Introduction ---": {"History": {"Demise": {}, "Current uses": {"Comparison with other technologies": {}}}, "Construction": {"Body": {}, "Size and weight": {}, "Anode": {}, "Electron gun": {"Construction and method of operation": {}, "Gamma": {}}, "Deflection": {"Magnetic deflection": {}, "Electrostatic deflection": {}}, "Burn-in": {}, "Evacuation": {}, "Rebuilding": {}, "Reactivation": {}, "Phosphors": {"Phosphor persistence": {}}, "Limitations and workarounds": {"Blooming": {}, "Doming": {}, "High voltage": {}, "Size": {}, "Limits imposed by deflection": {}}}, "Types": {"Monochrome CRTs": {}, "Color CRTs": {"Shadow mask": {}, "Screen manufacture": {}, "Convergence and purity in color CRTs": {}, "Magnetic shielding and degaussing": {}, "Resolution": {}}, "Projection CRTs": {}, "Beam-index tube": {}, "Flat CRTs": {}, "Radar CRTs": {}, "Oscilloscope CRTs": {"Microchannel plate": {}, "Graticules": {}, "Image storage tubes": {}}, "Vector monitors": {}, "Data storage tubes": {}, "Cat's eye": {}, "Charactrons": {}, "Nimo": {}, "Flood-beam CRT": {}, "Print-head CRT": {}, "Zeus \u2013 thin CRT display": {}, "Slimmer CRT": {}}, "Health concerns": {"Ionizing radiation": {}, "Toxicity": {}, "Flicker": {}, "High-frequency audible noise": {}, "Implosion": {"Implosion protection": {}}, "Electric shock": {}}, "Security concerns": {}, "Recycling": {}, "See also": {}, "References": {}, "Selected patents": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cathode-ray tube --- Introduction ---|History": "[[File:Braun cathode ray tube.jpg|thumb|upright=1.6|Braun's original cold-cathode CRT, 1897]]\nCathode rays were discovered by [[Julius Pl\u00fccker]] and [[Johann Wilhelm Hittorf]].<ref>{{Cite book\n | first =Andr\u00e9\n | last =Martin\n | chapter =Cathode Ray Tubes for Industrial and Military Applications\n | editor-last =Hawkes\n | editor-first =Peter\n | title =Advances in Electronics and Electron Physics\n | volume =67\n | publisher =[[Academic Press]]\n | year =1986\n | isbn =9780080577333\n |doi=10.1016/S0065-2539(08)60331-5\n | page =183-328\n | quote ="Evidence for the existence of "cathode-rays" was first found by Pl\u00fccker and Hittorf ..."\n}}</ref> Hittorf observed that some unknown rays were emitted from the [[cathode]] (negative electrode) which could cast shadows on the glowing wall of the tube, indicating the rays were traveling in straight lines. In 1890, [[Arthur Schuster]] demonstrated cathode rays could be deflected by [[electric field]]s, and [[William Crookes]] showed they could be deflected by magnetic fields. In 1897, [[J. J. Thomson]] succeeded in measuring the charge-mass-ratio of cathode rays, showing that they consisted of negatively charged particles smaller than atoms, the first "[[subatomic particle]]s", which had already been named ''[[electron]]s'' by Irish physicist, [[George Johnstone Stoney]] in 1891. The earliest version of the CRT was known as the "Braun tube", invented by the German physicist [[Ferdinand Braun]] in 1897.<ref>\n{{cite journal |author1-first=Ferdinand |author1-last=Braun |author-link1=Ferdinand Braun|title=Ueber ein Verfahren zur Demonstration und zum Studium des zeitlichen Verlaufes variabler Str\u00f6me|journal=[[Annalen der Physik und Chemie]]|volume=60|page=552\u2013559|trans-title=On a process for the display and study of the course in time of variable currents|url=https://archive.org/details/sim_annalen-der-physik_1897_60_3/page/552/mode/2up|date=1987|access-date=2021-11-10|issue=3}} </ref>\nIt was a [[cold cathode|cold-cathode]] [[diode]], a modification of the [[Crookes tube]] with a [[phosphor]]-coated screen. Braun was the first to conceive the use of a CRT as a display device.<ref>{{cite book|last1=Lehrer |first1=Norman, H. |chapter=The Challenge of the Cathode-Ray Tube|title=Flat-Panel Displays and CRTs|editor-first=Lawrence E. |editor-last=Tannas Jr.|doi=10.1007/978-94-011-7062-8_6|isbn=978-94-011-7062-8 |pages=138\u2013176 |publisher=[[Van_Nostrand_Reinhold|Van Nostrand Reinhold Company Inc.]]|location=New York|date=1985}}</ref>\n\nIn 1908, [[Alan Archibald Campbell-Swinton]], fellow of the [[Royal Society]] (UK), published a letter in the scientific journal ''[[Nature (journal)|Nature]]'' in which he described how "distant electric vision" could be achieved by using a cathode-ray tube (or "Braun" tube) as both a transmitting and receiving device.<ref name="Swinton_DEV1">\n{{cite journal\n | author1-first= A. A.\n | author1-last= Campbell-Swinton\n | author-link = Alan_Archibald_Campbell-Swinton\n | title = Distant Electric Vision\n | journal = [[Nature_(journal)|Nature]]\n | volume = 78\n | issue = 2016\n | page = 151\n | date = 1908-06-18\n | doi=10.1038/078151a0| url = https://zenodo.org/record/1429503\n | bibcode = 1908Natur..78..151S\n | s2cid = 3956737\n }}</ref>\nHe expanded on his vision in a speech given in London in 1911 and reported in ''[[The Times]]''<ref>{{cite news | author       =<!--Staff writer(s)/no by-line.-->\n| title        = Distant Electric Vision\n| work         = [[The Times]]\n| location     = London\n| date         = 1911-11-15\n| page         = 24b\n| access-date  =\n}}</ref> and the ''Journal of the [[British Institute of Radiology|R\u00f6ntgen Society]]''.<ref name="Swinton_Braid">\n{{cite journal\n| last1        = Campbell Swinton\n| first1       = Alan A.\n| author-link1 = Alan_Archibald_Campbell-Swinton\n| date         = 1909-05-01\n| title        = Some Vacuum Tube Phenomena\n| url          = https://babel.hathitrust.org/cgi/pt?id=coo.31924053226902\n| journal      = J. R\u00f6ntgen Soc.\n| volume       = 5\n| issue        = 20\n| pages        = 59\u201383\n| doi          = 10.1259/jrs.1909.0058\n| access-date = 2021-11-10\n}}\n</ref><ref name="Swinton-Rontgen">{{cite book\n |last1=Shiers\n |first1=George\n |last2=Shiers\n |first2=May\n |date=1997\n |title=Early Television: A Bibliographic Guide to 1940\n |url=https://books.google.com/books?id=OlXsZdT8HUQC&q=swinton+rontgen\n |location=New York\n |publisher=[[Routledge]]\n |page= 56\n |isbn=9781135819989\n |series=Garland Reference Library of Social Science\n |volume =582\n}}\n</ref>\n\nThe first cathode-ray tube to use a [[hot cathode]] was developed by [[John Bertrand Johnson]] (who gave his name to the term [[Johnson\u2013Nyquist noise|Johnson noise]]) and Harry Weiner Weinhart of [[Western Electric]], and became a commercial product in 1922.{{citation needed|date=February 2020}} The introduction of hot cathodes allowed for lower acceleration anode voltages and higher electron beam currents, since the anode now only accelerated the electrons emitted by the hot cathode, and no longer had to have a very high voltage to induce electron emission from the cold cathode.<ref name="auto68">{{Cite book|author=Thorn-AEI Radio Valves and Tubes Limited|authorlink=Thorn_Lighting|url=http://www.r-type.org/articles/art-004e.htm|title=Electrons in Picture Tubes|location= United Kingdom|date=1964}}</ref>\n\nIn 1926, [[Kenjiro Takayanagi]] demonstrated a CRT television that received images with a 40-line resolution.<ref name="nhk.or.jp">{{cite web\n |url=http://www.nhk.or.jp/strl/aboutstrl/evolution-of-tv-en/p05/\n |url-status= dead\n |title=Kenjiro Takayanagi: The Father of Japanese Television\n |date=2002\n |website=\n |publisher=[[NHK]] (Japan Broadcasting Corporation)\n |archive-url= https://web.archive.org/web/20160101180643/http://www.nhk.or.jp/strl/aboutstrl/evolution-of-tv-en/p05/\n |archive-date= 2013-02-01\n |access-date= 2021-11-10\n}}</ref> By 1927, he improved the resolution to 100 lines, which was unrivaled until 1931.<ref>{{cite book |last1=Forrester |first1=Chris |title=High Above: The untold story of Astra, Europe's leading satellite company |date=2011 |publisher=[[Springer Science & Business Media]]|location=Heidelberg |isbn=978-3-642-12009-1 |page=220 |url=https://books.google.com/books?id=wQhlFaxDwrsC&pg=PA220 }}</ref> By 1928, he was the first to transmit human faces in half-tones on a CRT display.<ref name="abramson">\n{{cite book\n |last=Abramson\n |first=Albert\n |date=1995\n |title=Zworykin, Pioneer of Television\n |url=https://books.google.com/books?id=tyurXyEBPxkC&pg=PA231\n |location=Urbana\n |publisher=[[University of Illinois Press]]\n |page= 231\n |isbn=0-252-02104-5\n}}</ref> By 1935, he had invented an early all-electronic CRT television.<ref>\n{{cite magazine\n| author      = <!--Staff writer(s); no by-line.--> \n| title       = TV's Japanese Dad?\n| url         = https://books.google.com/books?id=DJsbJq2_djkC&pg=PA5\n| magazine    = [[Popular Photography]]\n| page        = 5\n| volume      = 97\n| issue       = 11\n| location    = New York\n| publisher   = [[Diamandis_Communications|Diamandis Communications Inc.]]\n| date        = November 1990\n| access-date = 2021-11-10\n}}</ref>\nIn 1927, [[Philo Farnsworth]] created a television prototype.<ref>{{cite web |author-last=Pruitt |author-first=Sarah |title=Who Invented Television? |df=dmy-all |date=2021-06-29 |website=History Channel |publisher=A&E Television Networks, LLC. |url=https://www.history.com/news/who-invented-television |access-date=2021-11-03}}</ref><ref>{{US patent|1773980}}: Television system (filed January 7, 1927, issued August 26, 1930)</ref><ref>{{US patent|1773981}}: Television receiving system (filed January 7, 1927, issued August 26, 1930)</ref><ref>{{US patent|1758359}}: Electric oscillator system (filed January 7, 1927, issued May 13, 1930)</ref><ref>{{US patent|1806935}}: Light valve (filed January 7, 1927, issued May 26, 1931)</ref>\nThe CRT was named in 1929 by inventor [[Vladimir K. Zworykin]],<ref name="abramson"/>{{rp|84}} who was influenced by Takayanagi's earlier work.<ref name="abramson"/> [[RCA]] was granted a trademark for the term (for its cathode-ray tube) in 1932; it voluntarily released the term to the public domain in 1950.<ref>{{cite magazine |title=RCA Surrenders Rights to Four Trade-Marks |magazine=[[Television/Radio_Age_(magazine)|Radio Age]] |date=October 1950 |page=21 |url=https://www.americanradiohistory.com/Archive-Radio-Age/Radio-Age-1950-October.pdf| location = New York\n| publisher = [[Radio Corporation of America]] }}</ref>\n\nIn the 1930s, [[Allen B. DuMont]] made the first CRTs to last 1,000 hours of use, which was one of the factors that led to the widespread adoption of television.<ref>{{cite news |last1=Hart |first1=Hugh |title=Jan. 29, 1901: DuMont Will Make TV Work |url=https://www.wired.com/2010/01/jan-29-1901-dumont-will-make-tv-work-2/ |work=Wired |date=28 January 2010 }}</ref>\n\nThe first commercially made electronic television sets with cathode-ray tubes were manufactured by [[Telefunken]] in Germany in 1934.<ref>\n{{cite web\n |url=http://www.earlytelevision.org/telefunken.html\n |title=Early Electronic TV Gallery: Telefunken\n |website=Early Television Museum\n |publisher=Early Television Foundation\n |access-date=2021-11-10\n}}\n</ref><ref>\n{{cite web\n |url=http://www.tvhistory.tv/1934-35-Telefunken-FEIII.JPG\n |title=1934\u201335 Telefunken FE-III CRT (30cm) Germany\n |website=Television History: The First 75 Years\n |publisher=TVhistory.tv\n |access-date=2021-11-10\n}}</ref>\n\nIn 1947, the [[cathode-ray tube amusement device]], the earliest known [[Interactivity|interactive]] [[electronic game]] as well as the first to incorporate a cathode-ray tube screen was created.<ref>{{cite book\n |last=Ivory\n |first=James D.\n |author-link=\n|chapter=A brief history of video games\n|editor1-first=Rachel\n|editor1-last=Cowert\n|editor2-first=Thorsten\n|editor2-last=Quandt\n|editor-link2=Thorsten_Quandt\n |date= 2016\n |title= The Video Game Debate: Unravelling the Physical, Social, and Psychological Effects of Digital Games\n |chapter-url= https://books.google.com/books?id=Y-JzCgAAQBAJ&dq=The+Video+Game+Debate&pg=PR4\n |location= London\n |publisher= [[Routledge]]\n |page= 3\n |isbn= 978-1-138-83160-5\n}}</ref>\n\nFrom 1949 to the early 1960s, there was a shift from circular CRTs to rectangular CRTs, although the first rectangular CRTs were made in 1938 by Telefunken.<ref>{{Cite web|url=http://www.earlytelevision.org/telefunken_rfb_t2.html|website=www.earlytelevision.org |title=Pre-War CRTs: Telefunken RFB/T2 |publisher=Early Television Museum |access-date= 2021-11-11}}</ref><ref name="auto68"/><ref>\n{{cite magazine\n| last        = Codel\n| first       = Martin\n| title       = TV Digest<!-- unsure of which page originating wikipedian was using for reference, amend title if known-->\n| url         = https://worldradiohistory.com/Archive-TV-Digest/40s/TV-Digest-1949-01.pdf\n| magazine    = TV Digest\n| location    = Washington D.C.\n| publisher   = Radio News Bureau\n| date        = 1949\n| access-date = 2021-11-11\n}}</ref><ref name="auto42">\n{{cite magazine\n| author      = <!--Staff writer(s); no by-line.--> \n| title       = Electronic Age<!-- unsure of which page originating wikipedian was using for reference, amend title if known-->\n| url         = https://worldradiohistory.com/Archive-Radio-Age/ElectronicAge-1964-Autumn.pdf\n| magazine    = Electronic Age\n| location    = New York\n| publisher   = [[Radio Corporation of America]]\n| date        = Autumn 1964\n| access-date = 2021-11-10\n}}</ref><ref name="auto102">{{Cite web|url=https://www.earlytelevision.org/motorola_prototype_crt.html|title=Picture Tubes: Motorola Prototype Rectangular Color CRT|website=www.earlytelevision.org\n |last=Harland\n |first=Doug\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref><ref name="auto30">\n{{cite magazine\n| last        = Keller\n| first       = Peter A.\n| date        = October 2007\n| title       = Tektronic CRT History: Part 5: The hybrid years: 1961-64\n| url         = https://vintagetek.org/wp-content/uploads/2017/07/Tek-CRT-History-Keller-Oct-2007-Pt5.pdf\n| magazine    = The Tube Collector\n| volume      = 9\n| issue       = 5\n| page        = 5\n| location    = Ashland, Oregon\n| publisher   = Tube Collectors Association\n| access-date =2021-11-11\n}}</ref> While circular CRTs were the norm, European TV sets often blocked portions of the screen to make it appear somewhat rectangular while American sets often left the entire front of the CRT exposed or only blocked the upper and lower portions of the CRT.<ref>{{Cite web|url=https://collection.sciencemuseumgroup.org.uk/objects/co8067379/raytheon-model-m-1601-console-television-receiver-television-receiver|title=Raytheon Model M-1601 console television receiver|website=collection.sciencemuseumgroup.org.uk\n |publisher=[[Science_Museum,_London|Science Museum Group]]\n |access-date=2021-11-11\n}}</ref><ref>{{Cite web|url=https://www.earlytelevision.org/westinghouse_890cku19.html|title=Westinghouse 19 Inch Color TV Ad|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11}}</ref>\n\nIn 1954, RCA produced some of the first color CRTs, the 15GP22 CRTs used in the [[CT-100]],<ref name="auto90">{{Cite web|url=https://www.earlytelevision.org/15gp22.html|title=15GP22 Color CRT|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref>  the first color TV set to be \nmass produced.<ref>{{Cite web|url=https://lancasteronline.com/news/rca-pioneers-remember-making-the-first-color-tv-tube/article_2d5e6fb1-6c7d-55ce-82b8-255fe3c15497.html|title=RCA pioneers remember making the first color TV tube\n|author1-first=Tim\n|author1-last=Mekeel\n|author2-first=Laura\n|author2-last=Knowles\n|website=LancasterOnline\n|date=2013-09-12\n|publisher=LNP Media Group Inc.\n|access-date=2021-11-11\n|archive-url= https://web.archive.org/web/20210804052600/https://lancasteronline.com/news/rca-pioneers-remember-making-the-first-color-tv-tube/article_2d5e6fb1-6c7d-55ce-82b8-255fe3c15497.html\n|archive-date= 2021-08-04\n}}</ref> The first rectangular color CRTs were also made in 1954.<ref>{{cite web|url=https://www.earlytelevision.org/dumont_color_crt.html|title=DuMont Experimental Color \n |website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref><ref>\n{{cite book\n |author-link=Zenith_Electronics\n |date=1955\n |title=The Zenith Story: A History from 1918 to 1954\n |url=https://www.radiomuseum.org/dsp_multipage_pdf.cfm?pdf=zenith_story_radiomuseum_org.pdf\n |location=Chicago\n |publisher=Zenith Electronics Corporation\n |page= 24\n}}</ref> However, the first rectangular color CRTs to be offered to the public were made  in 1963. One of the challenges that had to be solved to produce the rectangular color CRT was convergence at the corners of the CRT.<ref name="auto102"/><ref name="auto42"/> In 1965, brighter rare earth phosphors began replacing dimmer and cadmium-containing red and green phosphors. Eventually blue phosphors were replaced as well.<ref>{{Cite patent |country=US | number=3989977 |title=Color picture tube |pubdate=1976-11-02|inventor1-first=Shigeya|inventor1-last=Ashizaki|assign=[[Matsushita_Electric|Matsushita Electronics Corp.]]}}</ref><ref>{{Cite patent |country=US |number=3394084 |title=Rare earth activated indium borate cathodoluminescent phosphors |pubdate=1968-07-23|inventor1-first=Frank J|inventor1-last=Avella|assign=[[GTE|General Telephone and Electronics Laboratories Inc.]]\n}}</ref><ref>{{Cite patent |country=US |number=3418246 |inventor-first=Martin R|inventor-last=Royce|title=Rare earth activated yttrium and gadolinium oxy-chalcogenide phosphors|pubdate=1968-12-24|assign=[[Radio Corporation of America]]}}</ref><ref name="auto93">\n{{cite report\n | author      = <!-- none, staff writers -->\n | date        = <!-- or |year= -->\n | title       = RCA Phosphors for Cathode-Ray Tubes, Black-and-White and Color Picture Tubes, and other Applications\n | url         = http://bitsavers.trailing-edge.com/components/rca/crt/TPM-1508A_RCA_Phosphors_Oct61.pdf\n | publisher   = Electron Tube Division, [[Radio Corporation of America]]\n | format      = booklet\n | location    = Harrison, NJ\n | docket      = TPM-1508A\n | access-date = 2021-11-11\n}}</ref><ref name="auto40">{{cite web|url=https://toshiba-mirai-kagakukan.jp/learn/history/ichigoki/1972cathode_ray/index_j.htm|title=\u6771\u829d\u672a\u6765\u79d1\u5b66\u9928\uff1a\u4e16\u754c\u521d\u306e\u30d6\u30e9\u30c3\u30af\u30fb\u30b9\u30c8\u30e9\u30a4\u30d7\u65b9\u5f0f\u30d6\u30e9\u30a6\u30f3\u7ba1|language=ja\n |trans-title=The world's first black stripe cathode-ray tube\n |date=1995\n |website=Toshiba Science Museum\n |publisher=Toshiba Corporation\n |access-date=}}</ref><ref>{{Cite patent |number=3440080 |inventor1-last=Tamura|inventor1-first= Michio|inventor2-last= Nakamura |inventor2-first=Mitsuyoshi |pubdate=1969-04-22|assign=[[Sony Corp.]]|country=US|title=Cathode ray tube color screen and method of producing same}}</ref>\n\nThe size of CRTs increased over time, from 20 inches in 1938,<ref>{{Cite web|url=https://www.crtsite.com/page3.html|title=Cathode Ray Tubes: The CRT History page|website=www.crtsite.com\n |publisher=The Cathode Ray Tube\n |access-date=2021-11-11\n}}</ref> to 21 inches in 1955,<ref name="auto59">{{Cite web|url=http://www.earlytelevision.org/21axp22.html|title=21AXP22|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref><ref>{{Cite web|url=https://www.earlytelevision.org/22_inch_color_tubes.html|title=CBS and Westinghouse 22 Inch Rectangular Color Tubes|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11}}</ref> 35 inches by 1985,<ref>{{Cite web|url=https://www.pcworld.com/article/142550/article.html|title=1988 vs. 2008: A Tech Retrospective|date= 2008-02-22|website=[[PC_World|PCWorld.com]]\n |archive-url=https://web.archive.org/web/20210506223854/https://www.pcworld.com/article/142550/article.html\n |last=Waring\n |first=Becky\n |publisher=[[International_Data_Group|IDG Communications Inc.]]\n |access-date=2021-11-11\n |url-status=dead\n |archive-date=2021-05-06\n}}</ref> and 43 inches by 1989.<ref>\n{{cite web\n |url=https://docs.sony.com/release/PVM4300.pdf\n |title= Sony Trinitron Color Video Monitor PVM-4300\n |date=1989\n |website=www.sony.com\n |publisher=[[Sony Corp.]]\n |access-date=2021-11-11\n |url-status=dead\n |archive-date=2020-10-28\n |archive-url=https://web.archive.org/web/20201028191204/https://www.docs.sony.com/release/PVM4300.pdf\n}} The Sony KX-45ED1, released in 1988 in Japan, was even larger, at 45 visible inches but a reliable source of information has not been located. \n<!--  2x catalogue pages are available here [https://www.zhihu.com/question/57752884] but will require translation from Japanese for verification --></ref> However, experimental 31 inch CRTs were made as far back as 1938.<ref>{{Cite web|url=https://www.earlytelevision.org/rca_31inch_crt.html|title=RCA 31 Inch CRT|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref>\n\nIn 1960, the [[Aiken tube]] was invented. It was a CRT in a flat-panel display format with a single electron gun.<ref>{{Cite web|url=https://www.earlytelevision.org/geer_color_crt.html|title=Geer Experimental Color CRT|website=www.earlytelevision.org\n |publisher=Early Television Museum\n |access-date=2021-11-11\n}}</ref><ref>{{Cite web|url=https://www.theatlantic.com/photo/2011/10/50-years-ago-the-world-in-1961/100172/|title=50 Years Ago: The World in 1961|first=Alan|last=Taylor|website=www.theatlantic.com\n |date=2011-10-19\n |publisher=[[The Atlantic Monthly Group]]\n |access-date=2021-11-11\n|quote= 24:TV viewers of the 1970s will see their programs on sets quite different from today's, if designs now being worked out are developed. At the Home Furnishings Market in Chicago, Illinois, on June 21, 1961, a thin TV screen is a feature of this design model. Another feature is an automatic timing device which would record TV programs during the viewers' absence to be played back later. The 32x22-inch color screen is four inches thick.\n}}</ref> Deflection was electrostatic and magnetic but due to patent problems it was never put into production. It was also envisioned as a [[head-up display]] in aircraft.<ref>\n{{cite magazine\n| author      = <!--Staff writer(s); no by-line.--> \n| date        = January 1958\n| title       = Thin Tube Foretells Wall TV and Sky view for Air Pilot\n| url         = https://archive.org/details/PopularMechanics1958/Popular_Mechanics_01_1958/page/n105/mode/2up\n| magazine    = [[Popular Mechanics]]\n| volume      = 109\n| issue       = 1\n| location    = Chicago\n| publisher   = Popular Mechanics Company\n| page        = 104\n| access-date = 2021-11-11\n}}\n</ref>  By the time patent issues were solved RCA had already invested heavily in conventional CRTs.<ref>\n{{cite interview \n|last = Aiken\n|first= William Ross\n|interviewer= Jaimeson Cobleigh\n|title= William Ross Aiken\n|type= telephone\n|date= 1996-10-30\n|publisher= [[Institute_of_Electrical_and_Electronics_Engineers|IEEE History Center]]\n|url= https://ethw.org/Oral-History:William_Ross_Aiken\n|access-date=2021-11-11\n}}</ref>\n\n1968 marks the release of Sony TRINITRON brand with the model KV-1310, which was based on Aperture Grille technology. It was acclaimed to have improved the output brightness. The Trinitron screen was identical with its upright cylindrical shape due to its unique triple cathode single gun construction.\n\nIn 1987, flat-screen CRTs were developed by [[Zenith Electronics|Zenith]] for computer monitors, reducing reflections and helping increase image contrast and brightness.<ref name="auto106">\n{{cite magazine\n| last        = Free\n| first       = John\n| title       = Flat-face tubes \u2014 crisp new look for computers, TVs\n| url         = https://books.google.com/books?id=Frbtc4mssNQC&q=flat+face+tubes\n| magazine    = [[Popular Science]]\n| location    = New York\n| publisher   = [[Times_Mirror_Company|Times Mirror Magazines Inc.]]\n| date        = August 1986\n| pages       = 22\u201324\n|volume=229\n|issue=4\n| access-date = 2021-11-11\n}}\n</ref><ref name="auto84">\n{{cite magazine\n| last        = Soviero\n| first       = Marcelle M.\n| title       = Truer-to-life TV: Flat-look CRTs\n| url         = https://books.google.com/books?id=kwEAAAAAMBAJ&q=flat-look+crts&pg=PA45\n| magazine    = [[Popular Science]]\n| location    = New York\n| publisher   = [[Times_Mirror_Company|Times Mirror Magazines Inc.]]\n| date        = April 1992\n| page        = 45\n|volume=240\n|issue=4\n| access-date = 2021-11-11\n}}\n</ref> Such CRTs were expensive which limited their use to computer monitors.<ref name="auto94">{{Cite web|url=https://www.chicagotribune.com/news/ct-xpm-1991-09-30-9103140692-story.html|title=TV makers tuning in to flat screens to help round out sales|first=Rich|last=Warren|website=chicagotribune.com\n |date=1991-09-30\n |publisher=[[Chicago Tribune]]\n |access-date=2021-11-11\n}}</ref> Attempts were made to produce flat-screen CRTs using inexpensive and widely available [[float glass]].<ref name="auto37">{{Cite web|url=https://www.crtsite.com/page3-3.html|title=Prototype CRTs|website=www.crtsite.com\n |publisher=The Cathode Ray Tube\n |access-date=2021-11-11\n}}</ref>\n\nIn 1990, the first CRTs with HD resolution were released to the market by Sony.<ref>{{Cite web|url=http://home.bt.com/tech-gadgets/television/retro-tech-the-crt-tv-11363858003032|title=History of the CRT TV|website=BT.com|url-status=dead <!-- not archived on Wayback Machine -->}}</ref>\n\nIn the mid 1990s, some 160 million CRTs were made per year.<ref name="auto27">{{Cite web|url=https://www.toshiba.co.jp/about/press/1995_12/pr2101.htm|title=Toshiba : Press Releases 21 December, 1995}}</ref>\n\n[[Flat-panel display]]s dropped in price and started significantly displacing cathode-ray tubes in the 2000s. After several predictions,<ref>{{Cite web|url=https://amp.smh.com.au/national/lcds-to-outsell-crt-monitors-soon-idc-20051007-gdm7ln.html|title=LCDs to outsell CRT monitors soon: IDC|website=amp.smh.com.au}}</ref><ref>{{Cite web|url=https://www.computerworld.com/article/2580706/idc--lcds-to-outsell-crt-monitors-in-2003.amp.html|title=IDC: LCDs to outsell CRT monitors in 2003 | Computerworld|website=www.computerworld.com}}</ref> LCD monitor sales began exceeding those of CRTs in 2003-2004<ref>{{Cite web|url=https://www.zdnet.com/article/lcds-outsell-crts-in-q4-2003/|title=LCDs outsell CRTs in Q4 2003|first=Kristyn|last=Maslog-Levis|website=ZDNet}}</ref><ref>{{Cite web|url=https://www.audioholics.com/news/lcds-overtake-and-outsell-crts-in-q3-2004|title=LCDs Overtake and Outsell CRTs in Q3 2004!|website=Audioholics Home Theater, HDTV, Receivers, Speakers, Blu-ray Reviews and News}}</ref><ref>{{Cite web|url=https://www.eetimes.com/lcd-monitors-outsold-crts-in-q3-says-displaysearch/|title=LCD monitors outsold CRTs in Q3, says DisplaySearch | EE Times}}</ref> and LCD TV sales started exceeding those of CRTs in the US in 2005,<ref>{{Cite web|url=https://www.tvtechnology.com/news/canada-daytek-adds-40inch-lcd-hd|title=Canada: Daytek Adds 40-Inch LCD HD|website=TVTechnology|date=28 September 2005}}</ref> in Japan in 2005-2006,<ref>{{Cite web|url=https://www.arnnet.com.au/article/149076/lcd_tv_shipments_beat_crt_japan_2005/|title=LCD TV shipments beat CRT in Japan in 2005|website=ARN}}</ref><ref>{{Cite web|url=https://www.macworld.com/article/1055675/bigscreen_crt_tv_business_in_j.html|title=Big-screen CRT TV business in Japan all but over|date=24 July 2006|website=Macworld}}</ref><ref>{{Cite web|url=https://www.cio.com/article/2445384/big-screen-crt-tv-biz-in-japan-all-but-finished.html|title=Big-Screen CRT TV Biz in Japan All But Finished|date=24 July 2006|website=CIO}}</ref> in Europe in 2006,<ref>{{Cite web|url=https://www.macworld.com/article/1054094/lcdsales.amp.html|title=LCDs outsell CRTs in Europe | Macworld|website=www.macworld.com}}</ref> globally in 2007-2008,<ref>{{Cite web|url=https://www.theregister.com/2008/02/22/displaysearch_crt_lcd_global_q4/|title=Global LCD TV sales overtake CRT|first=James|last=Sherwood|website=www.theregister.com}}</ref><ref>{{Cite web |url=http://graphics.thomsonreuters.com/10/04/GLB_TVTECH0410.gif |title=Archived copy |access-date=3 April 2018 |archive-url=https://web.archive.org/web/20131011135725/http://graphics.thomsonreuters.com/10/04/GLB_TVTECH0410.gif |archive-date=11 October 2013 |url-status=dead  }}</ref> and in India in 2013.<ref>{{Cite web|url=https://www.thehindubusinessline.com/news/Indians-switch-off-cathode-ray-TVs/article20802085.ece|title=Indians switch off cathode ray TVs|first=Amit|last=Mitra|website=@businessline}}</ref>\n\nIn the mid 2000s, Canon and Sony presented the [[surface-conduction electron-emitter display]] and [[field-emission display]]s, respectively. They both were flat-panel displays that had one (SED) or several (FED) electron emitters per subpixel in place of electron guns; the electron emitters were placed on a sheet of glass and the electrons were accelerated to a nearby sheet of glass with phosphors using an anode voltage; the electrons were not focused making each subpixel essentially a flood beam CRT. They were never put into mass production as LCD technology was significantly cheaper, eliminating the market for such displays.<ref>{{Cite web|url=https://www.goodgearguide.com.au/article/357585/canon_signals_end_road_sed_tv_dreams/|title=Canon signals end of the road for SED TV dreams|website=Good Gear Guide}}</ref>\n\nThe last known manufacturer of (in this case, recycled)<ref>{{Cite web|url=https://resource-recycling.com/e-scrap/2015/01/09/three-more-years-of-videocon-crt-demand/|title=Three more years of Videocon CRT demand?|date=9 January 2015}}</ref> CRTs, [[Videocon]], ceased in 2015.<ref name="auto88">{{Cite web|url=https://resource-recycling.com/e-scrap/2020/03/12/a-look-at-where-californias-crt-glass-is-going/|title=A look at where California's CRT glass is going|date=12 March 2020}}</ref><ref>{{Cite news|url=https://www.npr.org/sections/alltechconsidered/2016/08/15/489629491/saying-goodbye-to-old-technology-and-a-legendary-nyc-repair-shop|title=Saying Goodbye To Old Technology \u2014 And A Legendary NYC Repair Shop|website=NPR.org}}</ref> CRT TVs stopped being made around the same time.<ref>{{Cite news|url=https://www.business-standard.com/article/companies/onida-exits-dvd-business-aims-to-phase-out-crt-tv-manufacturing-by-2015-114012800284_1.html|title=Onida exits DVD business, aims to phase out CRT TV manufacturing by 2015|newspaper=Business Standard India|date=28 January 2014|last1=Narasimhan|first1=T. E.}}</ref>\n\nIn 2015, several CRT manufacturers were convicted in the US for [[price fixing]]. The same occurred in Canada in 2018.<ref>{{Cite web|url=https://globalnews.ca/news/4648296/price-fixing-settlement-old-tvs/|title=Price fixing settlement: If you owned a TV in 1995 you could get money back|website=Global News}}</ref><ref>{{cite news |last1=Levine |first1=Dan |title=Companies in cathode ray tube price fixing lawsuit reach $528 million deal |url=https://www.reuters.com/article/us-samsung-philips-settlement-idUSKBN0OH3BX20150601 |work=Reuters |date=1 June 2015 }}</ref>\n\n Worldwide sales of CRT computer monitors peaked in 2000, at 90 million units, while those of CRT TVs peaked in 2005 at 130 million units.<ref name="auto20">{{Cite web|url=https://news.mit.edu/2010/crt-recycle|title=CRTs going down the tubes? Hardly|website=MIT News | Massachusetts Institute of Technology}}</ref>\n\nBeginning in the late 90s to the early 2000s CRTs began to be replaced with LCDs, starting first with computer monitors smaller than 15 inches in size<ref>{{Cite web|url=http://edition.cnn.com/2002/TECH/ptech/02/15/crt.monitors.idg/|title=CNN.com - Are you looking at your last CRT? - February 15, 2002|website=edition.cnn.com}}</ref> largely because of their lower bulk.<ref>{{Cite web|url=https://fcw.com/articles/1999/07/25/flexscan-l66-a-sound-choice-in-flatpanel-displays.aspx|title=FlexScan L66: A sound choice in flat-panel displays|first1=Pat|last1=McClung|date=July 25, 1999|website=FCW}}</ref>  Among the first<ref>{{Cite web|url=https://apnews.com/article/e8298d721b0631753c8a451d73591073|title=GE Announces Tube Plant Closing; 790 Jobs Cut|website=AP NEWS}}</ref> manufacturers to stop CRT production was [[Hitachi]], in 2001,<ref>{{Cite web|url=https://www.extremetech.com/extreme/50240-hitachi-will-still-manufacture-crt-monitors|title=Hitachi Will Still Manufacture CRT Monitors - ExtremeTech|website=www.extremetech.com}}</ref><ref>{{Cite web|url=https://www.theregister.com/2001/07/26/hitachi_to_ditch_crt_monitors/|title=Hitachi to ditch CRT monitors|first=Robert|last=Blincoe|website=www.theregister.com}}</ref> followed by Sony in Japan in 2004,<ref name="auto62">{{Cite web|url=https://www.marketwatch.com/story/sony-to-stop-making-old-style-cathode-ray-tube-tvs|title=Sony to stop making old-style cathode ray tube TVs|website=MarketWatch}}</ref> [[Technicolor SA|Thomson]] in the US in 2004,<ref>{{Cite web|url=https://www.tvtechnology.com/amp/news/thomson-shuts-down-american-picture-tube-production|title=Thomson shuts down American picture tube production | TV Technology|website=www.tvtechnology.com|date=29 March 2004}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=wpatIq2M5FYC&q=asahi+closes+crt+plant&pg=SL8-PA23|title=Certain Color Television Receivers from China, Invs. 731-TA-1034 (Final)|publisher=DIANE Publishing|isbn=9781457820526|via=Google Books}}</ref> [[Matsushita Electric Industrial|Matsushita]] [[Toshiba]] picture display in 2005 in the US,<ref>{{Cite web|url=https://www.computerworld.com/article/2811895/hitachi--matsushita--toshiba-cement-lcd-venture-plan.amp.html|title=Hitachi, Matsushita, Toshiba cement LCD venture plan | Computerworld|website=www.computerworld.com}}</ref> 2006 in Malaysia<ref name="auto51">{{Cite web|url=https://www.networkworld.com/article/2305303/panasonic-toshiba-venture-to-shut-malaysia-crt-plant.html|title=Panasonic-Toshiba venture to shut Malaysia CRT plant|first=Martyn|last=Williams|date=27 July 2006|website=Network World}}</ref> and 2007 in China,<ref>{{Cite web|url=http://www.digitimes.com/news/a20070906PB203.html|title=Panasonic China stops CRT TV production at Shandong plant|website=DIGITIMES}}</ref> Sony in the US in 2006,<ref>{{Cite web|url=https://hackaday.com/2018/11/30/retrotechtacular-some-of-the-last-crts-from-the-factory-floor/|title=Retrotechtacular: Some Of The Last CRTs From The Factory Floor|date=30 November 2018}}</ref> Sony in Singapore and Malaysia for the Latin American and Asian markets in 2008,<ref name="auto62"/><ref>{{Cite web|url=https://spectrum.ieee.org/tech-talk/semiconductors/devices/sony_pulls_plug_on_historic_tr|title=Full Page Reload|website=IEEE Spectrum: Technology, Engineering, and Science News}}</ref>  Samsung SDI in 2007<ref>{{Cite web|url=https://m.koreatimes.co.kr/pages/article.asp?newsIdx=15271|title=Samsung SDI Struggles to Close CRT Lines|date=10 December 2007|website=m.koreatimes.co.kr}}</ref><ref>{{Cite web|url=http://world.kbs.co.kr/service/news_view.htm?lang=e&Seq_Code=49355|title=Samsung Hungary to Halt CRT Production|website=world.kbs.co.kr}}</ref> and 2012<ref>{{Cite web|url=https://m.pulsenews.co.kr/view.php?year=2012&no=206660|title=Samsung SDI halts CRT production in Malaysia plant - Pulse by Maeil Business News Korea|website=m.pulsenews.co.kr}}</ref><ref>{{Cite web|url=https://www.mk.co.kr/news/english/view/2012/04/206660/|title=Samsung SDI halts CRT production in Malaysia plant|date=3 April 2012|website=www.mk.co.kr}}</ref> and Cathode Ray Technology (formerly Philips) in 2012<ref>{{Cite web|url=https://www.crtsite.com/page3-2.html|title=Cathode Ray Technology|website=www.crtsite.com}}</ref><ref>{{Cite web|url=http://lampes-et-tubes.info/cr/cr131.php?l=e|title=Cathode Ray Technology B.V. Engineering Model Type D10-XXX|website=lampes-et-tubes.info}}</ref> and [[Videocon]] in 2015-16.<ref>{{Cite web|url=https://resource-recycling.com/e-scrap/2015/10/22/videocon-shuts-down-furnaces-and-stokes-concerns/|title=Videocon shuts down furnaces - and stokes concerns|date=22 October 2015}}</ref><ref name="auto43">{{Cite web|url=https://resource-recycling.com/e-scrap/2018/02/01/demand-dwindling-questions-swirl-around-videocon/|title=With demand dwindling, questions swirl around Videocon|date=1 February 2018}}</ref><ref name="auto72">{{Cite web|url=https://resource-recycling.com/e-scrap/2016/03/03/videocon-begins-accepting-crt-glass-again/|title=Videocon begins accepting CRT glass again|first=Bobby|last=Elliott|date=3 March 2016}}</ref><ref name="auto88"/> Ekranas in Lithuania<ref>{{Cite web|url=https://www.baltictimes.com/news/articles/15121/|title=Ekranas files for bankruptcy, Vilniaus Vingis braces for worst|website=www.baltictimes.com}}</ref> and LG.Philips Displays<ref>{{Cite web|url=https://www.electronicsweekly.com/news/products/led/lg-philips-seeks-bankruptcy-protection-in-europe-2006-01/|title=LG.Philips seeks bankruptcy protection in Europe|first=Steve|last=Bush|date=27 January 2006}}</ref> went bankrupt in 2005 and 2006 respectively. Matsushita Toshiba stopped in the US in 2004 due to losses of $109 million,<ref>{{Cite web|url=https://www.computerweekly.com/news/2240058540/LCD-plant-coming-soon-after-CRT-close-down|title=LCD plant coming soon after CRT close-down|website=ComputerWeekly.com}}</ref> and in Malaysia in 2006 due to losses that almost equaled their sales.<ref name="auto51"/> The last CRT TVs at CES were shown by Samsung in 2007<ref name="auto86">{{Cite web|url=https://www.engadget.com/2007-01-07-samsung-introduces-2007-lcd-plasma-dlp-and-crt-lineup.html|title=Samsung introduces 2007 LCD, plasma, DLP and CRT lineup|website=Engadget}}</ref> and the last mass produced model was introduced by LG in 2008 for developing markets due to its low price.<ref>{{Cite web|url=https://www.techradar.com/news/television/tv/world-s-thinnest-crt-tv-bucks-all-trends-167665|title=World's thinnest CRT TV bucks all trends|first=J. Mark|last=Lytle|website=TechRadar|date=9 March 2007}}</ref><ref name="auto101">{{Cite web|url=https://news.softpedia.com/news/LG-Presents-the-Slimmest-CRT-TV-Display-49012.shtml|title=LG Presents the Slimmest CRT TV Display|first=Bogdan|last=Solca|website=softpedia|date=9 March 2007}}</ref>{{better reference needed|date=December 2021}} The last CRT TV by a major manufacturer was introduced by LG in 2010.<ref>{{Cite web|url=https://www.engadget.com/amp/2010-01-25-lgs-classic-tv-gives-old-crt-new-legs.html|title=LG's Classic TV gives old CRT new legs|website=Engadget}}</ref><ref>{{Cite web|url=https://www.techhive.com/article/187656/Retro_LG_Introduce_CRT_TV.amp.html|title=LG Goes Retro, Introduces New CRT TV|website=www.techhive.com}}</ref>\n\nCRTs were first replaced by LCD in first world countries such as Japan and Europe in the 2000s and continued to be popular in third world countries such as Latin America,<ref>{{Cite web|url=https://amp.smh.com.au/technology/lg-samsung-try-to-save-the-crt-20050819-gdlwh2.html|title=LG, Samsung try to save the CRT|website=amp.smh.com.au}}</ref><ref name="auto20"/> China, Asia and the Middle East due to their low price compared to contemporary flat panel TVs,<ref>{{Cite web|url=https://www.techradar.com/news/television/what-s-happening-to-all-the-crt-tvs-525649|title=What's happening to all the CRT TVs?|first=Dean|last=Evans|website=TechRadar|date=6 February 2009}}</ref> and later in markets like rural India, however in around 2014 even rural markets started favoring LCD over CRT, leading to the demise of the technology.<ref>{{Cite web|url=https://www.thehindubusinessline.com/info-tech/Rise-of-flat-screen-televisions-lowers-the-curtain-on-the-bulky-box/article20921397.ece|title=Rise of flat-screen televisions lowers the curtain on the bulky box|first=R.|last=Ravikumar|website=@businessline}}</ref>\n\nDespite being a mainstay of display technology for decades, CRT-based computer monitors and televisions are now virtually a dead technology. Demand for CRT screens dropped in the late 2000s. The rapid advances and falling prices of [[liquid-crystal display|LCD]] [[flat panel]] technology \u2014 first for computer monitors, and then for televisions \u2014 spelled doom for competing display technologies such as CRT, [[rear-projection television|rear-projection]], and [[plasma display]].<ref>{{cite news |last=Wong|first=May|title=Flat Panels Drive Old TVs From Market |publisher=AP via USA Today |date= 22 October 2006 |url=https://www.usatoday.com/tech/products/gear/2006-10-22-crt-demise_x.htm |access-date=8 October 2006}}</ref> Despite efforts from Samsung and LG to make CRTs competitive with their LCD and plasma counterparts, offering slimmer and cheaper models to compete with similarly sized and more expensive LCDs,<ref>{{Cite web|url=https://www.cnet.com/news/lg-philips-displays-ups-production-of-slim-crts/|title=LG.Philips Displays ups production of slim CRTs|first=Richard|last=Shim|website=CNET}}</ref><ref>{{Cite web|url=https://www.smh.com.au/technology/lg-samsung-try-to-save-the-crt-20050819-gdlwh2.html|title=LG, Samsung try to save the CRT|date=19 August 2005|website=The Sydney Morning Herald}}</ref><ref>{{Cite web|url=https://m.hexus.net/ce/news/audio-visual/4947-samsung-unveils-hdtv-compatible-crt/|title=Samsung unveils HDTV-compatible CRT - Audio Visual - News - HEXUS.net|website=m.hexus.net}}</ref><ref name="auto9">{{cite web | title=Philips division launches slim CRTs | website=South China Morning Post | date=2003-01-28 | url=https://www.scmp.com/article/404922/philips-division-launches-slim-crts | language=id | access-date=2020-12-11}}</ref><ref>{{Cite web|url=https://amp.smh.com.au/world/worlds-slimmest-crt-digital-tv-built-20040720-gdjdmo.html|title=World's slimmest CRT digital TV built|website=amp.smh.com.au}}</ref> CRTs eventually became obsolete and were relegated to developing markets once LCDs fell in price, with their lower bulk, weight and ability to be wall mounted coming as pluses.\n\nMost high-end CRT production had ceased by around 2010,<ref>{{cite news |url=http://www.veritasetvisus.com/LCDTVA/LCDTVA-8,%20Spring-Summer%202009.pdf |title= The Standard TV|publisher= Veritas et Visus |access-date=12 June 2008}}</ref> including high-end Sony and Panasonic product lines.<ref>{{cite news |url=http://www.signonsandiego.com/uniontrib/20060120/news_1n20sony.html |title=End of an era |newspaper=The San Diego Union-Tribune |date=20 January 2006 |access-date=12 June 2008 |archive-url=https://web.archive.org/web/20080615135249/http://www.signonsandiego.com/uniontrib/20060120/news_1n20sony.html |archive-date=15 June 2008 |url-status=dead }}</ref><ref>{{cite news |url=http://www.engadgethd.com/2005/12/01/matsushita-says-good-bye-to-crts/ |title=Matsushita says good-bye to CRTs |publisher=engadgetHD |date=1 December 2005 |access-date=12 June 2008 |url-status=dead |archive-url=https://web.archive.org/web/20090114110526/http://www.engadgethd.com/2005/12/01/matsushita-says-good-bye-to-crts/ |archive-date=14 January 2009}}</ref> In Canada and the United States, the sale and production of high-end CRT TVs ({{Convert|30|in|cm|adj=on}} screens) in these markets had all but ended by 2007. Just a couple of years later, inexpensive "combo" CRT TVs ({{Convert|20|in|cm|adj=on}} screens with an integrated VHS player) disappeared from discount stores.\n\nElectronics retailers such as Best Buy steadily reduced store spaces for CRTs. In 2005, Sony announced that they would stop the production of CRT computer displays. Samsung did not introduce any CRT models for the 2008 model year at the 2008 Consumer Electronics Show; on 4 February 2008, they removed their 30" wide screen CRTs from their North American website and did not replace them with new models.<ref>{{cite news |url=http://www.samsung.com/us/consumer/subtype/subtype.do?group=televisions&type=televisions&subtype=slimfithdtv |title=SlimFit HDTV|publisher=Samsung |access-date=12 June 2008 |archive-url= https://web.archive.org/web/20080110164950/http://www.samsung.com/us/consumer/subtype/subtype.do?group=televisions&type=televisions&subtype=slimfithdtv <!-- Bot retrieved archive --> |archive-date= 10 January 2008}}</ref>\n\nIn the United Kingdom, [[DSG International (retailer)|DSG (Dixons)]], the largest retailer of domestic electronic equipment, reported that CRT models made up 80\u201390% of the volume of televisions sold at Christmas 2004 and 15\u201320% a year later, and that they were expected to be less than 5% at the end of 2006. Dixons ceased selling CRT televisions in 2006.<ref>{{cite news |title=The future is flat as Dixons withdraws sale of 'big box' televisions |newspaper=London Evening Standard |date=26 November 2006 |url=http://www.thisislondon.co.uk/news/article-23376023-details/The+future+is+flat+as+Dixons+withdraws+sale+of+'big+box'+televisions/article.do |archive-url=https://archive.today/20130505112036/http://www.thisislondon.co.uk/news/article-23376023-details/The+future+is+flat+as+Dixons+withdraws+sale+of+'big+box'+televisions/article.do |url-status=dead |archive-date=5 May 2013 |access-date=3 December 2006 }}</ref>\n\nCRTs' demise has made maintaining arcade machines made before the wide adoption of flat-panel displays difficult, due to a lack of spare replacement CRTs. (CRTs may need replacement due to wear as explained further below.) Repairing CRTs, although possible, requires a high level of skill.<ref name="auto65">{{Cite web|url=https://venturebeat.com/2017/03/03/what-the-death-of-the-crt-display-technology-means-for-classic-arcade-machines/|title=Donkey Kong's failing liver: What the death of the CRT display technology means for classic arcade machines|date=3 March 2017}}</ref>\n\n While CRTs had declined dramatically in the late 2000s, they are still widely used by consumers and some industries. CRTs do have some distinct advantages over other newer technologies.\n\nBecause a CRT doesn't need to draw a full image and instead uses [[Interlaced video|interlaced]] lines, a CRT is faster than an LCD which draws the entire image. CRTs are also able to correctly display certain [[Image resolution|resolutions]], such as the 256x224 resolution of the [[Nintendo Entertainment System]] (NES).<ref>{{Cite web|title=Nintendo Entertainment System Specs|url=https://www.cnet.com/products/nintendo-entertainment-system/|access-date=8 September 2020|website=CNET|language=en}}</ref> This is also an example of the most common usage of CRTs by consumers, retro video gaming. Some reasons for this include:\n\n*CRTs are able to correctly display the often 'oddball' resolutions that many older consoles use.\n*CRTs have the best quality when watching analog programming such as on VHS or through an RF signal.\n\nSome industries still use CRTs because it is either too much effort, downtime, and/or cost to replace them, or there is no substitute available; a notable example is the airline industry. Planes such as the [[Boeing 747-400]] and the [[Airbus A320 family|Airbus A320]] used CRT instruments in their [[glass cockpit]]s instead of mechanical instruments.<ref>{{Cite web|last=Pal|first=Soumyadeep|title=The Iconic Boeing 747 Heads Into The Sunset. An Enduring Legacy.|url=https://qnewshub.com/business/the-iconic-boeing-747-heads-into-the-sunset-an-enduring-legacy/|access-date=8 September 2020|website=QNewsHub|language=en-US}}</ref> Airlines such as [[Lufthansa]] still use CRT technology, which also uses [[floppy disk]]s for navigation updates.<ref>{{Cite web|date=11 August 2020|title=The Boeing 747-400 Is Still Updated With Floppy Disks - Here's Why|url=https://simpleflying.com/boeing-747-400-floppy-disk-updates/|access-date=8 September 2020|website=Simple Flying|language=en-US}}</ref>\n\nCRTs also tend to be more durable than their flat panel counterparts,<ref name="auto105"/> though specialised LCDs that have similar durability also exist.\n\n {{main|Comparison of CRT, LCD, Plasma, and OLED displays}}\n*LCD advantages over CRT: Lower bulk, power consumption and heat generation, higher refresh rates (up to 360hz),<ref>{{Cite web|url=https://www.pcmag.com/reviews/asus-rog-swift-360hz-pg259qn|title=Asus ROG Swift 360Hz PG259QN Review|website=PCMAG}}</ref> higher contrast ratios\n*CRT advantages over LCD: Better color reproduction, no motion blur, multisyncing available in many monitors, no input lag<ref name="eurogamer"/> \n*OLED advantages over CRT: Lower bulk, similar color reproduction,<ref name="eurogamer"/> higher contrast ratios, similar refesh rates (over 60Hz, up to 120hz)<ref>{{Cite web|url=https://www.cnet.com/news/best-tv-for-ps5-and-xbox-series-x-series-s-in-2020-lg-oled-samsung-qled-sony-tcl-and-vizio/|title=Which TV is best for PS5 and Xbox Series X?|first=Geoffrey|last=Morrison|website=CNET}}</ref><ref>{{Cite web|url=https://www.rtings.com/tv/reviews/lg/c9-oled|title=LG C9 OLED Review (OLED55C9PUA, OLED65C9PUA, OLED77C9PUA)|website=RTINGS.com}}</ref><ref>{{Cite web|url=https://www.gizchina.com/2020/11/07/lg-admits-that-oled-tvs-will-have-problems-with-variable-refresh-rate-vrr-below-120-hz/|title=LG admits that OLED TVs will have problems with variable refresh rate (VRR) below 120 Hz|date=November 7, 2020|website=Gizchina.com}}</ref> but not on computer monitors,<ref>{{Cite web|url=https://www.displayninja.com/best-oled-monitor/|title=OLED Monitors In 2020 : Current Market Status|date=23 November 2020|website=DisplayNinja}}</ref> also suffers from motion blur<ref>{{Cite web|url=https://www.cnet.com/how-to/to-120hz-and-beyond-the-pros-and-cons-of-how-4k-tvs-reduce-motion-blur/|title=Motion blur on 4K TVs: What it is and how to fight it|first=Geoffrey|last=Morrison|website=CNET}}</ref>\n\nOn CRTs, refresh rate depends on resolution, both of which are ultimately limited by the maximum horizontal scanning frequency of the CRT; motion blur also depends on the decay time of the phosphors; phosphors that decay too slowly for a given refresh rate may cause smearing or motion blur on the image. In practice CRTs are limited to a refresh rate of 160hz.<ref>{{Cite web|url=https://www.cnet.com/products/samsung-syncmaster-997mb-crt-monitor-19-series/|title=Samsung SyncMaster 997MB - CRT monitor - 19" Series Specs|website=CNET}}</ref> LCDs that can compete with OLED (Dual Layer, and mini-LED LCDs) are not available in high refresh rates, although quantum dot LCDs (QLEDs) are available in high refresh rates (up to 144Hz)<ref>{{Cite web|url=https://www.displayninja.com/samsung-c32hg70-review/|title=Samsung C32HG70 Review 2020: What You Need To Know|date=29 October 2020|website=DisplayNinja}}</ref> and are competitive in color reproduction with OLEDs.<ref>{{Cite web|url=https://www.cnet.com/news/samsung-qled-vs-lg-oled-how-the-two-best-tv-technologies-compare-in-2020/|title=QLED or OLED? We compare the two best TV technologies|first=David|last=Katzmaier|website=CNET}}</ref>\n\nCRT monitors can still outperform LCD and OLED monitors in input lag, as there is no signal processing between the CRT and the display connector of the monitor, since CRT monitors often use VGA which provides an analog signal that can be fed to a CRT directly. Video cards designed for use with CRTs may have a [[RAMDAC]] to generate the analog signals needed by the CRT.<ref>{{cite journal |last1=Kim |first1=Chul |title=Production of shadow-mask-improved technology |journal=Journal of Materials Processing Technology |date=3 October 2002 |volume=127 |issue=3 |pages=409\u2013418 |doi=10.1016/s0924-0136(02)00435-1 }}</ref><ref name="auto105"/> Also, CRT monitors are often capable of displaying sharp images at several resolutions, an ability known as [[Multisync monitor|multisyncing]].<ref>{{Cite web|url=https://www.nec-display.com/ap/en_display/25th/index.html|title=MultiSync 25th Anniversary - The Evolution of the MultiSync | NEC Display Solutions|website=www.nec-display.com}}</ref> Due to these reasons CRTs are sometimes preferred by PC gamers in spite of their bulk, weight and heat generation.<ref>{{cite web | last=Martindale | first=Jon | title=New Report States CRT Monitors Are Still Better Than Modern Gaming Displays | website=Digital Trends | date=2019-09-17 | url=https://www.digitaltrends.com/computing/crt-monitor-modern-gaming/ | access-date=2020-12-11}}</ref><ref name="eurogamer">{{Cite web|url=https://www.eurogamer.net/amp/digitalfoundry-2019-modern-games-look-beautiful-on-crt-monitors|title=We played modern games on a CRT monitor - and the results are phenomenal | Eurogamer|website=www.eurogamer.net}}</ref>"}},
{"article_title": "CD-R", "pageid": "6780", "revid": "1060864139", "timestamp": "2021-12-18T03:54:55Z", "history_paths": [["CD-R --- Introduction ---", "History"]], "categories": ["audiovisual introductions in 1988", "compact disc", "optical computer storage media", "audio storage", "video storage", "japanese inventions", "dutch inventions", "information technology in the netherlands", "science and technology in the netherlands", "information technology in japan", "science and technology in japan"], "heading_tree": {"CD-R --- Introduction ---": {"History": {}, "Physical characteristics": {}, "Speed": {}, "Writing methods": {}, "Lifespan": {}, "Labeling": {}, "Disposal": {"Data confidentiality": {}, "Recycling": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"CD-R --- Introduction ---|History": "[[File:CD-R.jpg|left|thumb|Assorted CD-Rs]]\nOriginally named CD [[Write once read many|'''W'''rite-'''O'''nce (WO)]], the CD-R specification was first published in 1988 by [[Philips]] and [[Sony]] in the [[Rainbow Books|Orange Book]], which consists of several parts that provide details of the CD-WO, CD-MO ('''M'''agneto-'''O'''ptic), and CD-RW ('''R'''e'''W'''ritable). The latest editions have abandoned the use of the term "CD-WO" in favor of "CD-R", while "[[CD-MO]]" was little used.  Written CD-Rs and CD-RWs are, in the aspect of low-level encoding and data format, fully compatible with the audio CD (''Red Book'' [[CD-DA]]) and data CD (''Yellow Book'' [[CD-ROM]]) standards. The Yellow Book standard for CD-ROM only specifies a high-level data format and refers to the Red Book for all physical format and low-level code details, such as track pitch, linear bit density, and bitstream encoding. This means they use [[Eight-to-Fourteen Modulation]], [[Cross-Interleaved Reed-Solomon Coding|CIRC]] error correction, and, for [[CD-ROM]], the third error correction layer defined in the Yellow Book. Properly written CD-R discs on blanks of less than 80 minutes in length are fully compatible with the audio CD and CD-ROM standards in all details including physical specifications. 80-minute CD-R discs marginally violate the Red Book physical format specifications, and longer discs are noncompliant.  CD-RW discs have lower reflectivity than CD-R or pressed (non-writable) CDs and for this reason cannot meet the Red Book standard. Some hardware compatible with Red Book CDs may have difficulty reading CD-Rs and, because of their lower reflectivity, especially CD-RWs. To the extent that CD hardware can read extended-length discs or CD-RW discs, it is because that hardware has capability beyond the minimum required by the Red Book and Yellow Book standards (the hardware is more capable than it needs to be to bear the Compact Disc logo).{{Citation needed|date=November 2021}}\n\nCD-R recording systems available in 1990 were similar to the washing machine-sized Meridian CD Publisher, based on the two-piece rack mount [[Yamaha]] PDS audio recorder costing $35,000, not including the required external [[Error correction code|ECC]] circuitry for data encoding, [[SCSI]] hard drive subsystem, and [[MS-DOS]] control computer. \n\nOn July 3, 1991, the first recording of a concert directly to CD was made using a [[Yamaha YPDR 601]]. The concert was performed by [[Claudio Baglioni]] at the Stadio Flaminio in Rome, Italy. At that time, it was generally anticipated that recordable CDs would have a lifetime of no more than 10 years. However, as of July 2020 the CD from this live recording still plays back with no uncorrectable errors.{{citation needed|date=July 2020}}\n\nAlso in 1991, the first company to successfully & professionally duplicate CD-R media was CDRM Recordable Media. With quality technical media being limited from [[Taiyo Yuden]]. Early CD-R Media had Phthalocyanine dye, which has a light aqua color was used for duplication. By 1992, the cost of typical recorders was down to $10,000\u201312,000, and in September 1995, [[Hewlett-Packard]] introduced its model 4020i manufactured by Philips, which, at $995, was the first recorder to cost less than $1000.<ref>[https://web.archive.org/web/20030202233907/http://www.roxio.com/en/support/cdr/historycdr.html Roxio history of CD-R] from Roxio Newsletter 17 January 2000. Retrieved 19 September 2009</ref> As of the 2010s, devices capable of writing to CD-Rs and other types of writable CDs could be found under $20.{{citation needed |date= October 2021}}\n\nThe dye materials developed by [[Taiyo Yuden]] made it possible for CD-R discs to be compatible with Audio CD and CD-ROM discs.\n\nIn the United States, there is a market separation between "music" CD-Rs and "data" CD-Rs, the former being notably more expensive than the latter due to industry [[copyright]] arrangements with the [[RIAA]].<ref>[https://web.archive.org/web/20110129215159/http://www.time.com/time/magazine/article/0,9171,988955,00.html "A New Spin"], ''[[Time (magazine)|Time]]'', August 24, 1998</ref> Specifically, the price of every music CD-R includes a mandatory [[Royalty payment|royalty]] disbursed to RIAA members by the disc manufacturer; this grants the disc an "application flag" indicating that the royalty has been paid. Consumer standalone music recorders refuse to burn CD-Rs that are missing this flag. Professional CD recorders are not subject to this restriction and can record music to data discs. The two types of discs are functionally and physically identical save for this, and computer CD burners can record data and/or music to either.<ref>{{cite web|url=http://www.cdrfaq.org/faq07.html#S7-17 |title=What's the difference between "data" and "music" blanks? |publisher=Cdrfaq.org |access-date=2011-12-16}}</ref> New music CD-Rs are still being manufactured as of the late 2010s, although demand for them has declined as CD-based music recorders have been supplanted by other devices incorporating the same or similar functionality.<ref>{{Cite news|last=Savage|first=Mark|date=3 January 2019|title=Is this the end of owning music?|work=[[BBC]]|url=https://www.bbc.com/news/entertainment-arts-46735093|access-date=27 November 2021}}</ref>"}},
{"article_title": "Chrominance", "pageid": "6945", "revid": "946497605", "timestamp": "2020-03-20T15:07:10Z", "history_paths": [["Chrominance --- Introduction ---", "History"]], "categories": ["film and video technology", "color"], "heading_tree": {"Chrominance --- Introduction ---": {"History": {}, "Television standards": {}, "Digital systems": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Chrominance --- Introduction ---|History": "The idea of transmitting a [[color television]] signal with distinct [[Luma (video)|luma]] and chrominance components originated with [[Georges Valensi]], who patented the idea in 1938.<ref>French patent 841335, issued Feb. 6, 1939; cited in U.S. Patent 2375966 [http://www.google.com/patents?id=dbhHAAAAEBAJ&printsec=abstract&zoom=4&dq=ininventor:valensi+color+television#PPA20,M1 "System of Television in Colors"], issued May 15, 1945.</ref> Valensi's patent application described:\n\n<blockquote>\nThe use of two channels, one transmitting the predominating color (signal T), and the other the mean brilliance (signal t) output from a single television transmitter to be received not only by color television receivers provided with the necessary more expensive equipment, but also by the ordinary type of television receiver which is more numerous and less expensive and which reproduces the pictures in black and white only.\n</blockquote>\n\nPrevious schemes for color television systems, which were incompatible with existing monochrome receivers, transmitted [[RGB]] signals in various ways."}},
{"article_title": "Catapult", "pageid": "7063", "revid": "1047033632", "timestamp": "2021-09-28T17:22:10Z", "history_paths": [["Catapult --- Introduction ---"], ["Catapult --- Introduction ---", "Greek and Roman catapults"], ["Catapult --- Introduction ---", "Other ancient catapults"], ["Catapult --- Introduction ---", "Medieval catapults"]], "categories": ["projectile weapons", "siege engines", "obsolete technologies"], "heading_tree": {"Catapult --- Introduction ---": {"Etymology": {}, "Greek and Roman catapults": {}, "Other ancient catapults": {}, "Medieval catapults": {}, "Modern use": {"Military": {}, "Entertainment": {}, "Other": {}}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Catapult --- Introduction ---": "{{Short description|Pre-gunpowder projectile-launching device}}\n{{About|the projectile-launching artillery weapon|the handheld weapon|Slingshot|equipment to launch aircraft|Aircraft catapult}}\n{{Other uses}}\n{{pp-vandalism |small =yes}}\n[[File:Mang2.png|thumb|Basic diagram of catapult]]\nA '''catapult''' is a [[ballistics|ballistic]] device used to launch a [[projectile]] a great distance without the aid of [[gunpowder]] or other [[propellant]]s \u2013 particularly various types of ancient and medieval [[siege engine]]s.<ref>{{cite book|title= The art of the catapult: build Greek ballista, Roman onagers, English trebuchets, and more ancient artillery|last= Gurstelle|first= William|author-link= William Gurstelle|year= 2004|publisher= Chicago Review Press|location= Chicago|isbn= 978-1-55652-526-1|oclc= 54529037|url-access= registration|url= https://archive.org/details/artofcatapult00will}}</ref> A catapult uses the sudden release of stored [[potential energy]] to propel its payload. Most convert [[Tension (mechanics)|tension]] or [[Torsion (mechanics)|torsion]] energy that was more slowly and manually built up within the device before release, via springs, bows, twisted rope, elastic, or any of numerous other materials and mechanisms. \n\nIn use since ancient times, the catapult has proven to be one of the most persistently effective mechanisms in warfare. In modern times the term can apply to devices ranging from a simple hand-held implement (also called a "[[slingshot]]") to a mechanism for [[Aircraft catapult|launching aircraft from a ship]].\n\nThe earliest catapults date to at least the 4th century BC with the advent of the [[mangonel]] in [[ancient China]], a type of [[trebuchet|traction trebuchet]] and catapult.<ref name="Chevedden"/><ref name=Trebuchet/> Early uses were also attributed to [[Ajatashatru]] of [[Magadha]] in his war against the [[Licchavi (kingdom)|Licchavi]]s.<ref name="google">{{cite book|title=A History of Ancient and Early Medieval India: From the Stone Age to the 12th Century|author=Singh, U.|date=2008|publisher=Pearson Education|isbn=9788131711200|url=https://books.google.com/books?id=H3lUIIYxWkEC|page=272|access-date=October 5, 2014|url-status=live|archive-url=https://web.archive.org/web/20140703065417/http://books.google.com/books?id=H3lUIIYxWkEC|archive-date=July 3, 2014}}</ref> Greek catapults were invented in the early 4th century BC, being attested by [[Diodorus Siculus]] as part of the equipment of a Greek army in 399 BC, and subsequently used at the [[siege of Motya]] in 397 BC.<ref name="Diod. Sic. 14.42.1">Diod. Sic. 14.42.1.</ref><ref>Campbell, Duncan (2003), Greek and Roman Artillery 399 BC \u2013 AD 363, p.3"</ref>\n\n The word 'catapult' comes from the [[Latin]] 'catapulta', which in turn comes from the [[Greek language|Greek]] {{Lang-grc|\u03ba\u03b1\u03c4\u03b1\u03c0\u03ad\u03bb\u03c4\u03b7\u03c2}}<ref>{{cite EB1911|wstitle=Catapult}}</ref> (''katapelt\u0113s''), itself from \u03ba\u03b1\u03c4\u03ac (''kata''), "downwards"<ref>\n{{citation |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dkata%2F1 |contribution=\u03ba\u03b1\u03c4\u03ac |publisher=Tufts |first1=Henry George |last1=Liddell |first2=Robert |last2=Scott |title=A Greek-English Lexicon |type=definition |series=Perseus |url-status=live |archive-url=https://web.archive.org/web/20120513155555/http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dkata%2F1 |archive-date=2012-05-13 }}</ref> and \u03c0\u03ac\u03bb\u03bb\u03c9 (''pall\u014d''), "to toss, to hurl".<ref>{{Citation |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dpa%2Fllw |contribution=\u03c0\u03ac\u03bb\u03bb\u03c9 |first1=Henry George |last1=Liddell |first2=Robert |last2=Scott |title=A Greek-English Lexicon |publisher=Tufts |series=Perseus |url-status=live |archive-url=https://web.archive.org/web/20131111192039/http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dpa%2Fllw |archive-date=2013-11-11 }}.</ref><ref>{{citation |url=http://oxforddictionaries.com/definition/catapult |contribution=catapult |publisher=Oxford |title=Dictionaries |type=definition |url-status=live |archive-url=https://web.archive.org/web/20120702092148/http://oxforddictionaries.com/definition/catapult |archive-date=2012-07-02 }}</ref> Catapults were invented by the [[ancient Greeks]]<ref>{{cite journal |last=Schellenberg |first=Hans Michael |year=2006 |url=http://s145739614.online.de/fera/ausgabe3/Schellenberg.pdf |title=Diodor von Sizilien 14,42,1 und die Erfindung der Artillerie im Mittelmeerraum |journal=Frankfurter Elektronische Rundschau zur Altertumskunde |volume=3 |pages=14\u201323 |url-status=live |archive-url=https://web.archive.org/web/20131103073739/http://s145739614.online.de/fera/ausgabe3/Schellenberg.pdf |archive-date=2013-11-03 }}</ref>{{Sfn | Marsden | 1969 | pp = 48\u201364}} and in [[ancient India]] where they were used by the [[Magadha]]n Emperor [[Ajatshatru]] around the early to mid 5th century BC.<ref>Singh, U. (2008). A History of Ancient and Early Medieval India: From the Stone Age to the 12th Century. Pearson Education. p. 272. {{ISBN|9788131711200}}. Retrieved October 5, 2014.</ref>\n\n {{Main article|Greek and Roman artillery}}\n[[File:Ancient Mechanical Artillery. Pic 01.jpg|thumb|Ancient mechanical artillery: Catapults (standing), the chain drive of [[Polybolos]] (bottom center), [[Gastraphetes]] (on wall)]]\n[[File:Ancient Roman catapult - Discours de la religion des anciens Romains (1581) (14763485952) (enhanced).jpg|thumb|Engraving illustrating a Roman catapult design, 1581]]\n[[File:047 Conrad Cichorius, Die Reliefs der Traianss\u00e4ule, Tafel XLVII (Ausschnitt 02).jpg|thumb|Roman "catapult-nest" in the [[Trajan's Dacian Wars]]]]\nThe catapult and [[crossbow]] in Greece are closely intertwined. Primitive catapults were essentially "the product of relatively straightforward attempts to increase the range and penetrating power of missiles by strengthening the bow which propelled them".<ref name = "Barton C. Hacker" /> The historian [[Diodorus Siculus]] (fl. 1st century BC), described the invention of a mechanical arrow-firing catapult (''katapeltikon'') by a Greek task force in 399 BC.<ref name="Diod. Sic. 14.42.1"/><ref name = "Duncan Campbell, p.3">\n{{Harvnb\n | Campbell\n | 2003\n | p = 3\n}}.</ref>  The weapon was soon after employed against [[Sicilian Wars#The Second Sicilian War (410 BC\u2013340 BC)|Motya]] (397 BC), a key [[Ancient Carthage|Carthaginian]] stronghold in [[Sicily]].<ref>Diod. Sic. 14.50.4</ref><ref name="Duncan Campbell, p.8">{{Harvnb | Campbell | 2003 | p = 8}}.</ref>  Diodorus is assumed to have drawn his description from the highly rated{{Sfn | Marsden | 1969 | pp = 48f}} history of [[Philistus]], a contemporary of the events then. The introduction of crossbows however, can be dated further back: according to the inventor [[Hero of Alexandria]] (fl. 1st century AD), who referred to the now lost works of the 3rd-century BC engineer [[Ctesibius]], this weapon was inspired by an earlier foot-held crossbow, called the ''[[gastraphetes]]'', which could store more energy than the Greek bows. A detailed description of the ''gastraphetes'', or the "belly-bow",<ref name= "Serafina Cuomo">\n{{Citation\n | last = Cuomo\n | first = Serafina\n | jstor = 3836219\n | title = The Sinews of War: Ancient Catapults\n| journal = Science\n | year = 2004\n | volume = 303\n | issue = 5659\n | pages = 771\u2013772\n | doi = 10.1126/science.1091066\n | pmid = 14764855\n | s2cid = 140749845\n | url = https://eprints.bbk.ac.uk/644/1/Binder1.pdf\n }}.</ref>{{Page needed | date = December 2013}} along with a watercolor drawing, is found in Heron's technical treatise ''Belopoeica''.<ref name= "Duncan Campbell, p.4">\n{{Harvnb\n | Campbell\n | 2003\n | p = 4\n}}.</ref><ref>\n{{Citation\n | first1 = Stanley M\n | last1 = Burstein\n | first2 = Walter\n | last2 = Donlan\n | first3 = Sarah B\n | last3 = Pomeroy\n | first4 = Jennifer Tolbert\n | last4 = Roberts\n | year = 1999\n | title = Ancient Greece: A Political, Social, and Cultural History\n | publisher = Oxford University Press\n | isbn = 0-19-509742-4\n | page = [https://archive.org/details/ancientgreecepol00sara/page/366 366]\n | url = https://archive.org/details/ancientgreecepol00sara/page/366\n }}.</ref>\n\nA third Greek author, [[Biton (writer)|Biton]] (fl. 2nd century BC), whose reliability has been positively reevaluated by recent scholarship,<ref name = "Duncan Campbell, p.3" />{{Sfn | Lewis | 1999}} described two advanced forms of the ''gastraphetes'', which he credits to [[Zopyrus of Tarentum|Zopyros]], an engineer from [[Taranto|southern Italy]]. Zopyrus has been plausibly equated with a [[Pythagoreanism|Pythagorean]] of that name who seems to have flourished in the late 5th century BC.<ref>{{Citation | url = http://plato.stanford.edu/entries/pythagoreanism/ | first = Peter | last = Kingsley | title = Ancient Philosophy, Mystery and Magic | publisher = Clarendon | place = Oxford | year = 1995 | pages = 150ff}}.</ref>{{Efn | Lewis established a lower date of no later than the mid-4th century.{{Sfn | Lewis | 1999 | p = 160}}  So did de Camp.<ref>{{Citation | first = L Sprague | last = de Camp | title = Master Gunner Apollonios | journal = [[Technology and Culture]] | volume = 2 | number = 3 | year = 1961 | pages = 240\u20134 (241) | doi=10.2307/3101024| jstor = 3101024 }}.</ref>}}  He probably designed his bow-machines on the occasion of the sieges of [[Cumae]] and [[Milet]] between 421 BC and 401 BC.<ref>Biton 65.1\u201367.4, 61.12\u201365.1.</ref><ref name= "Duncan Campbell, p.5">{{Harvnb | Campbell | 2003 | p = 5}}.</ref> The bows of these machines already featured a winched pull back system and could apparently throw two missiles at once.<ref name="Duncan Campbell, p.8" />\n\n[[Philo of Byzantium]] provides probably the most detailed account on the establishment of a theory of belopoietics (''belos'' = "projectile"; ''poietike'' = "(art) of making") circa 200 BC. The central principle to this theory was that "all parts of a catapult, including the weight or length of the projectile, were proportional to the size of the torsion springs". This kind of innovation is indicative of the increasing rate at which geometry and physics were being assimilated into military enterprises.<ref name="Serafina Cuomo" />{{Page needed | date = December 2013}}\n\nFrom the mid-4th century BC onwards, evidence of the Greek use of arrow-shooting machines becomes more dense and varied: arrow firing machines (''katapaltai'') are briefly mentioned by [[Aeneas Tacticus]] in his treatise on siegecraft written around 350 BC.<ref name="Duncan Campbell, p.8"/> An extant inscription from the [[Athens|Athenian]] arsenal, dated between 338 and 326 BC, lists a number of stored catapults with shooting bolts of varying size and springs of sinews.<ref name = "Eric William Marsden, p.57">{{Harvnb | Marsden | 1969 | p = 57}}.</ref>  The later entry is particularly noteworthy as it constitutes the first clear evidence for the switch to [[torsion (mechanics)|torsion]] catapults, which are more powerful than the more-flexible crossbows and which came to dominate Greek and [[Ancient Rome|Roman]] artillery design thereafter.<ref name = "Duncan Campbell, p.8ff">{{Harvnb | Campbell | 2003 | pp = 8ff}}.</ref> This move to torsion springs was likely spurred by the engineers of Philip II of Macedonia.<ref name= "Serafina Cuomo"/>{{Page needed | date = December 2013}} Another Athenian inventory from 330 to 329 BC includes catapult bolts with heads and flights.<ref name = "Eric William Marsden, p.57" /> As the use of catapults became more commonplace, so did the training required to operate them. Many Greek children were instructed in catapult usage, as evidenced by "a 3rd Century B.C. inscription from the island of Ceos in the Cyclades [regulating] catapult shooting competitions for the young".<ref name="Serafina Cuomo"/> Arrow firing machines in action are reported from [[Philip II of Macedon|Philip II]]'s siege of [[Perinth]] ([[Thrace]]) in 340 BC.<ref name="Eric William Marsden, p.60">{{Harvnb | Marsden | 1969 | p = 60}}.</ref>  At the same time, Greek fortifications began to feature high towers with shuttered windows in the top, which could have been used to house anti-personnel arrow shooters, as in [[Aigosthena]].<ref>{{Citation | first = Josiah | last = Ober | title = Early Artillery Towers: Messenia, Boiotia, Attica, Megarid | journal = American Journal of Archaeology | volume = 91 | number = 4 | year = 1987 | pages = 569\u2013604 (569) | doi=10.2307/505291| jstor = 505291 }}.</ref> Projectiles included both arrows and (later) stones that were sometimes lit on fire. [[Onomarchus]] of Phocis first used catapults on the battlefield against [[Philip II of Macedon]].{{Sfn | Ashley | 1998 | pp = 50, 446}}  Philip's son, [[Alexander the Great]], was the next commander in recorded history to make such use of catapults on the battlefield{{Sfn | Ashley | 1998 | p = 50}} as well as to use them during sieges.<ref>{{Citation | last1 = Skelton | first1 = Debra | first2 = Pamela | last2 = Dell | url = https://books.google.com/books?id=O8TDQG6jiG4C&pg=PA21 | title = Empire of Alexander the Great | place = New York | publisher = Facts on File | year = 2003 | isbn = 978-0-8160-5564-7 | access-date = January 31, 2013 | pages = 21, 26, 29 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=O8TDQG6jiG4C&pg=PA21 | archive-date = December 23, 2017 }}.</ref>\n\nThe Romans started to use catapults as arms for their wars against [[Syracuse, Italy|Syracuse]], Macedon, Sparta and Aetolia (3rd and 2nd centuries BC). The Roman machine known as an [[arcuballista]] was similar to a large crossbow.<ref>{{Citation | contribution = Arcuballista | place = [[France|FR]] | url = http://dagr.univ-tlse2.fr/sdx/dagr/feuilleter.xsp?tome=1&partie=1&numPage=400&filtre=arbal%C3%A8te%20&nomEntree=ARCUBALLISTA | language = fr | title = Dictionnaire des antiquit\u00e9s grecques et romaines | trans-title = Dictionary of Greek and Roman antiquities | publisher = Univ TLSE II | url-status = live | archive-url = https://web.archive.org/web/20081005121645/http://dagr.univ-tlse2.fr/sdx/dagr/feuilleter.xsp?tome=1&partie=1&numPage=400&filtre=arbal%C3%A8te%20&nomEntree=ARCUBALLISTA | archive-date = 2008-10-05 }}.</ref><ref>{{Citation | last = Bachrach | first = Bernard S | url = https://books.google.com/books?id=Is2WQyLMKV4C&pg=PA112 | title = Early Carolingian Warfare: Prelude to Empire | place = Philadelphia | publisher = University of Pennsylvania Press | year = 2001 | isbn = 978-0-8122-3533-3 | access-date = January 31, 2013 | pages = 110\u201312 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=Is2WQyLMKV4C&pg=PA112 | archive-date = December 23, 2017 }}.</ref><ref>{{Citation | last = Payne-Gallwey | first = Ralph | url = https://books.google.com/books?id=xCDK0twV82MC&pg=PA43 | title = The Crossbow: Its Military and Sporting History, Construction and Use | place = New York | publisher = Skyhorse | year = 2007 | isbn = 978-1-60239-010-2 | access-date = January 31, 2013 | pages = 43\u201344 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=xCDK0twV82MC&pg=PA43 | archive-date = December 23, 2017 }}.</ref> Later the Romans used [[ballista]] catapults on their warships.\n\n A catapult dating to the 19th century BC. was found on the walls of the fortress of [[Buhen]].<ref>{{Cite book|last1=Lewis|first1=Leo Richard|title=The Compendium of Weapons, Armor & Castles|last2=Tenney|first2=Charles R.|publisher=Nabu Press|year=2010|isbn=978-1146066846|pages=139}}</ref>\n\n[[Ajatshatru]] is recorded in Jaina texts as having used catapults in his campaign against the [[Licchavi (clan)|Licchavis]].<ref name="google"/>\n\nKing [[Uzziah]], who reigned in Judah until 750 BC, is documented as having overseen the construction of machines to "shoot great stones".<ref>{{bibleverse-lb|2|Chronicles|26:15|HE}}</ref>\n\nThe first recorded use of [[mangonel]]s was in ancient China.<ref name="Chevedden">Chevedden, Paul E.; et al. (July 1995). "The Trebuchet". Scientific American: 66\u201371. Original version.</ref><ref name=Trebuchet>[http://www.medievalists.net/2013/01/13/the-trebuchet/ The Trebuchet], Citation:"The trebuchet, invented in China between the fifth and third centuries B.C.E., reached the Mediterranean by the sixth century C.E. "</ref><ref name=PAUL>PAUL E. CHEVEDDEN, [http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf The Invention of the Counterweight Trebuchet: A Study in Cultural Diffusion] {{webarchive|url=https://web.archive.org/web/20140610032737/http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf |date=2014-06-10 }}, p.71, p.74, See citation:"The traction trebuchet, invented by the Chinese sometime before the fourth century B.C." in page 74</ref> They were probably used by the [[Mohist]]s as early as 4th century BC, descriptions of which can be found in the [[Mozi|''Mojing'']] (compiled in the 4th century BC).<ref name=Trebuchet/><ref name=PAUL/> In Chapter 14 of the ''Mojing'', the mangonel is described hurling hollowed out logs filled with burning charcoal at enemy troops.{{sfn|Liang|2006}} The mangonel was carried westward by the [[Pannonian Avars|Avars]] and appeared next in the eastern Mediterranean by the late 6th century AD, where it replaced torsion powered siege engines such as the ballista and onager due to its simpler design and faster rate of fire.{{sfn|Purton|2009|p=366}}<ref name="Chevedden"/>{{sfn|Graff|2016|p=141}} The Byzantines adopted the mangonel possibly as early as 587, the Persians in the early 7th century, and the Arabs in the second half of the 7th century.{{sfn|Graff|2016|p=86}} The [[Franks]] and [[Saxons]] adopted the weapon in the 8th century.{{sfn|Purton|2009|p=367}}\n\n [[File:Replica catapult.jpg|right|thumb|Replica of a Petraria Arcatinus]]\n[[File:Front of medieval catapult 2 in Mercato San Severino, Italy.JPG|thumb|Petraria Arcatinus catapult in Mercato San Severino, Italy]]\n[[File:Catapult 1 Mercato San Severino.jpg|thumb|Catapult 1 Mercato San Severino]]\n[[Castle]]s and fortified [[walled cities]] were common during this period and catapults were used as [[siege weapon]]s against them. As well as their use in attempts to breach walls, [[Early thermal weapons|incendiary missiles]], or diseased carcasses or garbage could be catapulted over the walls.\n\nDefensive techniques in the Middle Ages progressed to a point that rendered catapults largely ineffective. The [[Siege of Paris (885\u2013886)|Viking siege of Paris]] (885\u20136 A.D.) "saw the employment by both sides of virtually every instrument of siege craft known to the classical world, including a variety of catapults", to little effect, resulting in failure.<ref name="Barton C. Hacker">{{Citation | last = Hacker | first = Barton C | jstor = 3102042 | title = Greek Catapults and Catapult Technology: Science, Technology, and War in Ancient World| journal = Technology and Culture | year = 1968 | volume = 9 | issue = 1 | pages = 34\u201350 | doi = 10.2307/3102042 }}.</ref>\n\nThe most widely used catapults throughout the Middle Ages were as follows:<ref name="Middle Ages">{{Citation | url = http://www.middle-ages.org.uk/catapults.htm | title = Middle ages | contribution = Catapults | place = United Kingdom | url-status = live | archive-url = https://web.archive.org/web/20100924235615/http://middle-ages.org.uk/catapults.htm | archive-date = 2010-09-24 }}.</ref>\n\n; [[Ballista]]: Ballistae were similar to giant crossbows and were designed to work through torsion. The projectiles were large arrows or darts made from wood with an iron tip. These arrows were then shot "along a flat trajectory" at a target. Ballistae were accurate, but lacked firepower compared with that of a mangonel or trebuchet. Because of their immobility, most ballistae were constructed on site following a siege assessment by the commanding military officer.<ref name = "Middle Ages" />\n:\n; [[Springald]]: The springald's design resembles that of the ballista, being a crossbow powered by tension. The springald's frame was more compact, allowing for use inside tighter confines, such as the inside of a castle or tower, but compromising its power.<ref name="Middle Ages" />\n:\n; [[Mangonel]]: This machine was designed to throw heavy projectiles from a "bowl-shaped bucket at the end of its arm". Mangonels were mostly used for \u201cfiring various missiles at fortresses, castles, and cities,\u201d with a range of up to 1300 feet. These missiles included anything from stones to excrement to rotting carcasses. Mangonels were relatively simple to construct, and eventually wheels were added to increase mobility.<ref name = "Middle Ages" />\n:\n; [[Onager (siege weapon)|Onager]]: Mangonels are also sometimes referred to as Onagers. Onager catapults initially launched projectiles from a sling, which was later changed to a "bowl-shaped bucket". The word ''Onager'' is derived from the Greek word ''onagros'' for "wild ass", referring to the "kicking motion and force"<ref name = "Middle Ages"/> that were recreated in the Mangonel's design. Historical records regarding onagers are scarce. The most detailed account of Mangonel use is from \u201cEric Marsden's translation of a text written by Ammianus Marcellius in the 4th Century AD\u201d describing its construction and combat usage.<ref name="catapults.info">{{Citation|url=http://www.catapults.info/ |archive-url=https://web.archive.org/web/20020601094938/http://www.catapults.info/ |url-status=dead |archive-date=2002-06-01 |title=Catapults info }}.</ref>\n:\n; [[Trebuchet]]: [[File:MongolsBesiegingACityInTheMiddleEast13thCentury.jpg|thumb|left|Mongol warriors using trebuchet to besiege a city]] Trebuchets were probably the most powerful catapult employed in the Middle Ages. The most commonly used ammunition were stones, but "darts and sharp wooden poles" could be substituted if necessary. The most effective kind of ammunition though involved fire, such as "firebrands, and deadly [[Greek Fire]]". Trebuchets came in two different designs: Traction, which were powered by people, or Counterpoise, where the people were replaced with "a weight on the short end".<ref name= "Middle Ages"/>  The most famous historical account of trebuchet use dates back to the siege of [[Stirling Castle]] in 1304, when the army of Edward I constructed a giant trebuchet known as [[Warwolf]], which then proceeded to "level a section of [castle] wall, successfully concluding the siege".<ref name="catapults.info" />\n:\n; [[Trebuchet|Couillard]]: A simplified trebuchet, where the trebuchet's single counterweight is split, swinging on either side of a central support post.\n:\n; Leonardo da Vinci's catapult: [[Leonardo da Vinci]] sought to improve the efficiency and range of earlier designs. His design incorporated a large wooden [[leaf spring]] as an [[:wikt:accumulator|accumulator]] to power the catapult.{{citation needed |date=February 2011}} Both ends of the bow are connected by a rope, similar to the design of a [[bow and arrow]]. The leaf spring was not used to pull the catapult armature directly, rather the rope was wound around a drum. The catapult armature was attached to this drum which would be turned until enough potential energy was stored in the deformation of the spring. The drum would then be disengaged from the winding mechanism, and the catapult arm would snap around.{{citation needed | date = February 2011}} Though no records exist of this design being built during Leonardo's lifetime, contemporary enthusiasts have reconstructed it.{{citation needed|date=February 2011}}\n\n \n [[File:French grenade catapult.jpg|left|thumb|200px|French troops using a catapult to throw [[hand grenade]]s and other explosives during [[World War I]]]]\nThe last large scale military use of catapults was during the [[trench warfare]] of [[World War I]]. During the early stages of the war, catapults were used to throw [[hand grenade]]s across [[no man's land]] into enemy trenches. They were eventually replaced by small [[Mortar (weapon)|mortars]].\n\nIn the 1840s the invention of [[vulcanized]] [[natural rubber|rubber]] allowed the making of small hand-held catapults, either improvised from Y-shaped sticks or manufactured for sale; both were popular with children and teenagers. These devices were also known as [[slingshots]] in the USA.\n\nSpecial variants called [[aircraft catapult]]s are used to launch planes from land bases and sea carriers when the takeoff runway is too short for a powered takeoff or simply impractical to extend. Ships also use them to launch torpedoes and deploy bombs against submarines.{{dubious|date=June 2016}} Small catapults, referred to as "traps", are still widely used to launch [[clay target]]s into the air in the sport of [[clay pigeon shooting]].\n\n In the 1990s and into the early 2000s, a powerful catapult, a trebuchet, was used by thrill-seekers first on private property and in 2001-2002 at Middlemoor Water Park, Somerset, England, to experience being catapulted through the air for {{convert|100|ft|m|sp=us}}. The practice has been discontinued due to a fatality at the Water Park. There had been an injury when the trebuchet was in use on private property. Injury and death occurred when those two participants failed to land onto the safety net.<ref>{{cite journal |url=https://www.vanityfair.com/style/2004/02/oxford-university-dangerous-sports-club |title=Scandal: Extreme Oxford Sports |last=Martin |first=Brett |date=August 5, 2013 |journal=Vanity Fair |access-date=November 13, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170531102033/http://www.vanityfair.com/style/2004/02/oxford-university-dangerous-sports-club |archive-date=May 31, 2017 }}</ref> The operators of the trebuchet were tried, but found not guilty of manslaughter, though the jury noted that the fatality might have been avoided had the operators "imposed stricter safety measures."<ref>{{cite news |url=https://www.theguardian.com/education/2005/oct/31/highereducation.uk4 |title=Inquest told of student catapult death |newspaper=The Guardian |date=October 31, 2005 |access-date=December 8, 2014 |url-status=live |archive-url=https://web.archive.org/web/20150114133709/http://www.theguardian.com/education/2005/oct/31/highereducation.uk4 |archive-date=January 14, 2015 }}</ref><ref>{{cite web |url=http://news.bbc.co.uk/2/hi/uk_news/england/oxfordshire/4401024.stm |title=BBC NEWS UK England Oxfordshire - Safety doubts over catapult death |date=November 2, 2005 |access-date=December 8, 2014 |url-status=live |archive-url=https://web.archive.org/web/20141211151741/http://news.bbc.co.uk/2/hi/uk_news/england/oxfordshire/4401024.stm |archive-date=December 11, 2014 }}</ref> [[Human cannonball]] [[circus]] acts use a catapult launch mechanism, rather than gunpowder, and are risky ventures for the human cannonballs.<ref>{{cite news|url=http://www.straightdope.com/classics/a4_069.html|title=The Straight Dope: How do "human cannonballs" survive?|last=Adams|first=Cecil|date=1991-06-21|website=Straight Dope|publisher=Chicago Reader|access-date=November 13, 2017|url-status=live|archive-url=https://web.archive.org/web/20090106071839/http://www.straightdope.com/classics/a4_069.html|archive-date=January 6, 2009}}</ref>\n\nEarly [[launched roller coaster]]s used a catapult system powered by a diesel engine or a dropped weight to acquire their momentum,<ref>{{Cite book|url=https://books.google.com/books?id=OzZHAgAAQBAJ&pg=PA49|title=Coasters 101: An Engineer's Guide to Roller Coaster Design|last=Weisenberger|first=Nick|year=2013|isbn=9781468013559|pages=49\u201350|oclc=927712635|url-status=live|archive-url=https://web.archive.org/web/20171223060540/https://books.google.com/books?id=OzZHAgAAQBAJ&pg=PA49|archive-date=2017-12-23}}</ref> such as [[Shuttle Loop]] installations between 1977-1978. The catapult system for roller coasters has been replaced by [[flywheel]]s and later [[linear motor]]s.\n\n''[[Pumpkin chunking]]'' is another widely popularized use, in which people compete to see who can launch a pumpkin the farthest by mechanical means (although the world record is held by a pneumatic air cannon).\n\n In January 2011, a homemade catapult was discovered that was used to [[Smuggling|smuggle]] [[cannabis (drug)|cannabis]] into the United States from Mexico. The machine was found 20 feet from the border fence with {{convert|4.4|lb}} bales of cannabis ready to launch.<ref>{{Citation | url = http://www.popsci.com/diy/article/2011-01/mexican-authorities-seize-homemade-marijuana-hurling-catapult-border | newspaper = Pop Sci | date = Jan 2011 | title = Mexican authorities seize homemade marijuana hurling catapult at border | url-status = live | archive-url = https://web.archive.org/web/20110130043830/http://www.popsci.com/diy/article/2011-01/mexican-authorities-seize-homemade-marijuana-hurling-catapult-border | archive-date = 2011-01-30 }}.</ref>\n\n {{div col|colwidth=23em}}\n* [[Aircraft catapult]]\n* [[Mangonel]]\n* [[Mass driver]]\n* [[National Catapult Contest]]\n* [[Sling (weapon)]]\n* [[Trebuchet]]\n{{div col end}}\n\n {{Notelist}}\n\n {{Reflist|32em}}\n\n * {{Citation | last = Ashley | first = James R | url = https://books.google.com/books?id=nTmXOFX-wioC&pg=PA50 | title = The Macedonian Empire: The Era of Warfare Under Philip II and Alexander the Great, 359\u2013323 BC | place = Jefferson, NC | publisher = McFarland & Co | year = 1998 | isbn = 978-0-7864-1918-0 | access-date = January 31, 2013}}.\n* {{Citation | first = Duncan | last = Campbell | title = Greek and Roman Artillery 399 BC \u2013 AD 363 | publisher = Osprey | place = Oxford | year = 2003 | isbn = 1-84176-634-8}}.\n* {{Citation | first = MJT | last = Lewis | title = When was Biton? |journal = [[Mnemosyne (journal)|Mnemosyne]] | volume = 52 | number = 2 | year = 1999 | pages = 159\u201368 | doi=10.1163/1568525991528860}}.\n* {{Citation | first = Eric William | last = Marsden | title = Greek and Roman Artillery: Historical Development | publisher = Clarendon | place = Oxford | year = 1969 | isbn = 978-0-19-814268-3}}.\n\n {{Commons category |Catapults|Catapult}}\n{{Wiktionary |catapult}}\n* {{cite EB1911 |wstitle=Catapult |volume=5 |short=x}}\n* {{Citation | url = http://www.mlahanas.de/Greeks/war/CatapultTypes.htm | contribution = Types | title = Ancient Greek Artillery Technology | publisher = Mlahanas | place = [[Germany|DE]] | url-status = dead | archive-url = https://web.archive.org/web/20160112160714/http://www.mlahanas.de/Greeks/war/CatapultTypes.htm | archive-date = 2016-01-12 }}.\n* {{Citation | url = http://www.redstoneprojects.com/trebuchetstore/build_a_catapult.html | title = Trebuchet store | contribution = Catapult Plans and Design | publisher = Red stone projects}}.\n* {{Citation | url = http://www.redstoneprojects.com/trebuchetstore/catapultanimation.html | title = Trebuchet store | contribution = Animated Catapults | publisher = Red stone projects}}.\n* {{Citation | url = http://www.medieval-castle-siege-weapons.com/medieval-catapults.html | title = Medieval castle siege weapons | contribution = Medieval Catapult Articles | access-date = 2005-08-20 | archive-url = https://web.archive.org/web/20051027191657/http://www.medieval-castle-siege-weapons.com/medieval-catapults.html | archive-date = 2005-10-27 | url-status = dead }}.\n* {{Citation | url = http://www.fvc3.com/trebuchet | title = A Modern Spring Loaded Catapult in Action | publisher = FVC3 | access-date = 2009-10-10 | archive-url = https://web.archive.org/web/20100428232239/http://www.fvc3.com/trebuchet# | archive-date = 2010-04-28 | url-status = dead }}.\n\n{{Ancient mechanical artillery and hand-held missile weapons|state =collapsed}}\n{{Medieval mechanical artillery and hand-held missile weapons|state =collapsed}}\n{{Authority control}}", "Catapult --- Introduction ---|Greek and Roman catapults": "{{Main article|Greek and Roman artillery}}\n[[File:Ancient Mechanical Artillery. Pic 01.jpg|thumb|Ancient mechanical artillery: Catapults (standing), the chain drive of [[Polybolos]] (bottom center), [[Gastraphetes]] (on wall)]]\n[[File:Ancient Roman catapult - Discours de la religion des anciens Romains (1581) (14763485952) (enhanced).jpg|thumb|Engraving illustrating a Roman catapult design, 1581]]\n[[File:047 Conrad Cichorius, Die Reliefs der Traianss\u00e4ule, Tafel XLVII (Ausschnitt 02).jpg|thumb|Roman "catapult-nest" in the [[Trajan's Dacian Wars]]]]\nThe catapult and [[crossbow]] in Greece are closely intertwined. Primitive catapults were essentially "the product of relatively straightforward attempts to increase the range and penetrating power of missiles by strengthening the bow which propelled them".<ref name = "Barton C. Hacker" /> The historian [[Diodorus Siculus]] (fl. 1st century BC), described the invention of a mechanical arrow-firing catapult (''katapeltikon'') by a Greek task force in 399 BC.<ref name="Diod. Sic. 14.42.1"/><ref name = "Duncan Campbell, p.3">\n{{Harvnb\n | Campbell\n | 2003\n | p = 3\n}}.</ref>  The weapon was soon after employed against [[Sicilian Wars#The Second Sicilian War (410 BC\u2013340 BC)|Motya]] (397 BC), a key [[Ancient Carthage|Carthaginian]] stronghold in [[Sicily]].<ref>Diod. Sic. 14.50.4</ref><ref name="Duncan Campbell, p.8">{{Harvnb | Campbell | 2003 | p = 8}}.</ref>  Diodorus is assumed to have drawn his description from the highly rated{{Sfn | Marsden | 1969 | pp = 48f}} history of [[Philistus]], a contemporary of the events then. The introduction of crossbows however, can be dated further back: according to the inventor [[Hero of Alexandria]] (fl. 1st century AD), who referred to the now lost works of the 3rd-century BC engineer [[Ctesibius]], this weapon was inspired by an earlier foot-held crossbow, called the ''[[gastraphetes]]'', which could store more energy than the Greek bows. A detailed description of the ''gastraphetes'', or the "belly-bow",<ref name= "Serafina Cuomo">\n{{Citation\n | last = Cuomo\n | first = Serafina\n | jstor = 3836219\n | title = The Sinews of War: Ancient Catapults\n| journal = Science\n | year = 2004\n | volume = 303\n | issue = 5659\n | pages = 771\u2013772\n | doi = 10.1126/science.1091066\n | pmid = 14764855\n | s2cid = 140749845\n | url = https://eprints.bbk.ac.uk/644/1/Binder1.pdf\n }}.</ref>{{Page needed | date = December 2013}} along with a watercolor drawing, is found in Heron's technical treatise ''Belopoeica''.<ref name= "Duncan Campbell, p.4">\n{{Harvnb\n | Campbell\n | 2003\n | p = 4\n}}.</ref><ref>\n{{Citation\n | first1 = Stanley M\n | last1 = Burstein\n | first2 = Walter\n | last2 = Donlan\n | first3 = Sarah B\n | last3 = Pomeroy\n | first4 = Jennifer Tolbert\n | last4 = Roberts\n | year = 1999\n | title = Ancient Greece: A Political, Social, and Cultural History\n | publisher = Oxford University Press\n | isbn = 0-19-509742-4\n | page = [https://archive.org/details/ancientgreecepol00sara/page/366 366]\n | url = https://archive.org/details/ancientgreecepol00sara/page/366\n }}.</ref>\n\nA third Greek author, [[Biton (writer)|Biton]] (fl. 2nd century BC), whose reliability has been positively reevaluated by recent scholarship,<ref name = "Duncan Campbell, p.3" />{{Sfn | Lewis | 1999}} described two advanced forms of the ''gastraphetes'', which he credits to [[Zopyrus of Tarentum|Zopyros]], an engineer from [[Taranto|southern Italy]]. Zopyrus has been plausibly equated with a [[Pythagoreanism|Pythagorean]] of that name who seems to have flourished in the late 5th century BC.<ref>{{Citation | url = http://plato.stanford.edu/entries/pythagoreanism/ | first = Peter | last = Kingsley | title = Ancient Philosophy, Mystery and Magic | publisher = Clarendon | place = Oxford | year = 1995 | pages = 150ff}}.</ref>{{Efn | Lewis established a lower date of no later than the mid-4th century.{{Sfn | Lewis | 1999 | p = 160}}  So did de Camp.<ref>{{Citation | first = L Sprague | last = de Camp | title = Master Gunner Apollonios | journal = [[Technology and Culture]] | volume = 2 | number = 3 | year = 1961 | pages = 240\u20134 (241) | doi=10.2307/3101024| jstor = 3101024 }}.</ref>}}  He probably designed his bow-machines on the occasion of the sieges of [[Cumae]] and [[Milet]] between 421 BC and 401 BC.<ref>Biton 65.1\u201367.4, 61.12\u201365.1.</ref><ref name= "Duncan Campbell, p.5">{{Harvnb | Campbell | 2003 | p = 5}}.</ref> The bows of these machines already featured a winched pull back system and could apparently throw two missiles at once.<ref name="Duncan Campbell, p.8" />\n\n[[Philo of Byzantium]] provides probably the most detailed account on the establishment of a theory of belopoietics (''belos'' = "projectile"; ''poietike'' = "(art) of making") circa 200 BC. The central principle to this theory was that "all parts of a catapult, including the weight or length of the projectile, were proportional to the size of the torsion springs". This kind of innovation is indicative of the increasing rate at which geometry and physics were being assimilated into military enterprises.<ref name="Serafina Cuomo" />{{Page needed | date = December 2013}}\n\nFrom the mid-4th century BC onwards, evidence of the Greek use of arrow-shooting machines becomes more dense and varied: arrow firing machines (''katapaltai'') are briefly mentioned by [[Aeneas Tacticus]] in his treatise on siegecraft written around 350 BC.<ref name="Duncan Campbell, p.8"/> An extant inscription from the [[Athens|Athenian]] arsenal, dated between 338 and 326 BC, lists a number of stored catapults with shooting bolts of varying size and springs of sinews.<ref name = "Eric William Marsden, p.57">{{Harvnb | Marsden | 1969 | p = 57}}.</ref>  The later entry is particularly noteworthy as it constitutes the first clear evidence for the switch to [[torsion (mechanics)|torsion]] catapults, which are more powerful than the more-flexible crossbows and which came to dominate Greek and [[Ancient Rome|Roman]] artillery design thereafter.<ref name = "Duncan Campbell, p.8ff">{{Harvnb | Campbell | 2003 | pp = 8ff}}.</ref> This move to torsion springs was likely spurred by the engineers of Philip II of Macedonia.<ref name= "Serafina Cuomo"/>{{Page needed | date = December 2013}} Another Athenian inventory from 330 to 329 BC includes catapult bolts with heads and flights.<ref name = "Eric William Marsden, p.57" /> As the use of catapults became more commonplace, so did the training required to operate them. Many Greek children were instructed in catapult usage, as evidenced by "a 3rd Century B.C. inscription from the island of Ceos in the Cyclades [regulating] catapult shooting competitions for the young".<ref name="Serafina Cuomo"/> Arrow firing machines in action are reported from [[Philip II of Macedon|Philip II]]'s siege of [[Perinth]] ([[Thrace]]) in 340 BC.<ref name="Eric William Marsden, p.60">{{Harvnb | Marsden | 1969 | p = 60}}.</ref>  At the same time, Greek fortifications began to feature high towers with shuttered windows in the top, which could have been used to house anti-personnel arrow shooters, as in [[Aigosthena]].<ref>{{Citation | first = Josiah | last = Ober | title = Early Artillery Towers: Messenia, Boiotia, Attica, Megarid | journal = American Journal of Archaeology | volume = 91 | number = 4 | year = 1987 | pages = 569\u2013604 (569) | doi=10.2307/505291| jstor = 505291 }}.</ref> Projectiles included both arrows and (later) stones that were sometimes lit on fire. [[Onomarchus]] of Phocis first used catapults on the battlefield against [[Philip II of Macedon]].{{Sfn | Ashley | 1998 | pp = 50, 446}}  Philip's son, [[Alexander the Great]], was the next commander in recorded history to make such use of catapults on the battlefield{{Sfn | Ashley | 1998 | p = 50}} as well as to use them during sieges.<ref>{{Citation | last1 = Skelton | first1 = Debra | first2 = Pamela | last2 = Dell | url = https://books.google.com/books?id=O8TDQG6jiG4C&pg=PA21 | title = Empire of Alexander the Great | place = New York | publisher = Facts on File | year = 2003 | isbn = 978-0-8160-5564-7 | access-date = January 31, 2013 | pages = 21, 26, 29 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=O8TDQG6jiG4C&pg=PA21 | archive-date = December 23, 2017 }}.</ref>\n\nThe Romans started to use catapults as arms for their wars against [[Syracuse, Italy|Syracuse]], Macedon, Sparta and Aetolia (3rd and 2nd centuries BC). The Roman machine known as an [[arcuballista]] was similar to a large crossbow.<ref>{{Citation | contribution = Arcuballista | place = [[France|FR]] | url = http://dagr.univ-tlse2.fr/sdx/dagr/feuilleter.xsp?tome=1&partie=1&numPage=400&filtre=arbal%C3%A8te%20&nomEntree=ARCUBALLISTA | language = fr | title = Dictionnaire des antiquit\u00e9s grecques et romaines | trans-title = Dictionary of Greek and Roman antiquities | publisher = Univ TLSE II | url-status = live | archive-url = https://web.archive.org/web/20081005121645/http://dagr.univ-tlse2.fr/sdx/dagr/feuilleter.xsp?tome=1&partie=1&numPage=400&filtre=arbal%C3%A8te%20&nomEntree=ARCUBALLISTA | archive-date = 2008-10-05 }}.</ref><ref>{{Citation | last = Bachrach | first = Bernard S | url = https://books.google.com/books?id=Is2WQyLMKV4C&pg=PA112 | title = Early Carolingian Warfare: Prelude to Empire | place = Philadelphia | publisher = University of Pennsylvania Press | year = 2001 | isbn = 978-0-8122-3533-3 | access-date = January 31, 2013 | pages = 110\u201312 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=Is2WQyLMKV4C&pg=PA112 | archive-date = December 23, 2017 }}.</ref><ref>{{Citation | last = Payne-Gallwey | first = Ralph | url = https://books.google.com/books?id=xCDK0twV82MC&pg=PA43 | title = The Crossbow: Its Military and Sporting History, Construction and Use | place = New York | publisher = Skyhorse | year = 2007 | isbn = 978-1-60239-010-2 | access-date = January 31, 2013 | pages = 43\u201344 | url-status = live | archive-url = https://web.archive.org/web/20171223060540/https://books.google.com/books?id=xCDK0twV82MC&pg=PA43 | archive-date = December 23, 2017 }}.</ref> Later the Romans used [[ballista]] catapults on their warships.", "Catapult --- Introduction ---|Other ancient catapults": "A catapult dating to the 19th century BC. was found on the walls of the fortress of [[Buhen]].<ref>{{Cite book|last1=Lewis|first1=Leo Richard|title=The Compendium of Weapons, Armor & Castles|last2=Tenney|first2=Charles R.|publisher=Nabu Press|year=2010|isbn=978-1146066846|pages=139}}</ref>\n\n[[Ajatshatru]] is recorded in Jaina texts as having used catapults in his campaign against the [[Licchavi (clan)|Licchavis]].<ref name="google"/>\n\nKing [[Uzziah]], who reigned in Judah until 750 BC, is documented as having overseen the construction of machines to "shoot great stones".<ref>{{bibleverse-lb|2|Chronicles|26:15|HE}}</ref>\n\nThe first recorded use of [[mangonel]]s was in ancient China.<ref name="Chevedden">Chevedden, Paul E.; et al. (July 1995). "The Trebuchet". Scientific American: 66\u201371. Original version.</ref><ref name=Trebuchet>[http://www.medievalists.net/2013/01/13/the-trebuchet/ The Trebuchet], Citation:"The trebuchet, invented in China between the fifth and third centuries B.C.E., reached the Mediterranean by the sixth century C.E. "</ref><ref name=PAUL>PAUL E. CHEVEDDEN, [http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf The Invention of the Counterweight Trebuchet: A Study in Cultural Diffusion] {{webarchive|url=https://web.archive.org/web/20140610032737/http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf |date=2014-06-10 }}, p.71, p.74, See citation:"The traction trebuchet, invented by the Chinese sometime before the fourth century B.C." in page 74</ref> They were probably used by the [[Mohist]]s as early as 4th century BC, descriptions of which can be found in the [[Mozi|''Mojing'']] (compiled in the 4th century BC).<ref name=Trebuchet/><ref name=PAUL/> In Chapter 14 of the ''Mojing'', the mangonel is described hurling hollowed out logs filled with burning charcoal at enemy troops.{{sfn|Liang|2006}} The mangonel was carried westward by the [[Pannonian Avars|Avars]] and appeared next in the eastern Mediterranean by the late 6th century AD, where it replaced torsion powered siege engines such as the ballista and onager due to its simpler design and faster rate of fire.{{sfn|Purton|2009|p=366}}<ref name="Chevedden"/>{{sfn|Graff|2016|p=141}} The Byzantines adopted the mangonel possibly as early as 587, the Persians in the early 7th century, and the Arabs in the second half of the 7th century.{{sfn|Graff|2016|p=86}} The [[Franks]] and [[Saxons]] adopted the weapon in the 8th century.{{sfn|Purton|2009|p=367}}", "Catapult --- Introduction ---|Medieval catapults": "[[File:Replica catapult.jpg|right|thumb|Replica of a Petraria Arcatinus]]\n[[File:Front of medieval catapult 2 in Mercato San Severino, Italy.JPG|thumb|Petraria Arcatinus catapult in Mercato San Severino, Italy]]\n[[File:Catapult 1 Mercato San Severino.jpg|thumb|Catapult 1 Mercato San Severino]]\n[[Castle]]s and fortified [[walled cities]] were common during this period and catapults were used as [[siege weapon]]s against them. As well as their use in attempts to breach walls, [[Early thermal weapons|incendiary missiles]], or diseased carcasses or garbage could be catapulted over the walls.\n\nDefensive techniques in the Middle Ages progressed to a point that rendered catapults largely ineffective. The [[Siege of Paris (885\u2013886)|Viking siege of Paris]] (885\u20136 A.D.) "saw the employment by both sides of virtually every instrument of siege craft known to the classical world, including a variety of catapults", to little effect, resulting in failure.<ref name="Barton C. Hacker">{{Citation | last = Hacker | first = Barton C | jstor = 3102042 | title = Greek Catapults and Catapult Technology: Science, Technology, and War in Ancient World| journal = Technology and Culture | year = 1968 | volume = 9 | issue = 1 | pages = 34\u201350 | doi = 10.2307/3102042 }}.</ref>\n\nThe most widely used catapults throughout the Middle Ages were as follows:<ref name="Middle Ages">{{Citation | url = http://www.middle-ages.org.uk/catapults.htm | title = Middle ages | contribution = Catapults | place = United Kingdom | url-status = live | archive-url = https://web.archive.org/web/20100924235615/http://middle-ages.org.uk/catapults.htm | archive-date = 2010-09-24 }}.</ref>\n\n; [[Ballista]]: Ballistae were similar to giant crossbows and were designed to work through torsion. The projectiles were large arrows or darts made from wood with an iron tip. These arrows were then shot "along a flat trajectory" at a target. Ballistae were accurate, but lacked firepower compared with that of a mangonel or trebuchet. Because of their immobility, most ballistae were constructed on site following a siege assessment by the commanding military officer.<ref name = "Middle Ages" />\n:\n; [[Springald]]: The springald's design resembles that of the ballista, being a crossbow powered by tension. The springald's frame was more compact, allowing for use inside tighter confines, such as the inside of a castle or tower, but compromising its power.<ref name="Middle Ages" />\n:\n; [[Mangonel]]: This machine was designed to throw heavy projectiles from a "bowl-shaped bucket at the end of its arm". Mangonels were mostly used for \u201cfiring various missiles at fortresses, castles, and cities,\u201d with a range of up to 1300 feet. These missiles included anything from stones to excrement to rotting carcasses. Mangonels were relatively simple to construct, and eventually wheels were added to increase mobility.<ref name = "Middle Ages" />\n:\n; [[Onager (siege weapon)|Onager]]: Mangonels are also sometimes referred to as Onagers. Onager catapults initially launched projectiles from a sling, which was later changed to a "bowl-shaped bucket". The word ''Onager'' is derived from the Greek word ''onagros'' for "wild ass", referring to the "kicking motion and force"<ref name = "Middle Ages"/> that were recreated in the Mangonel's design. Historical records regarding onagers are scarce. The most detailed account of Mangonel use is from \u201cEric Marsden's translation of a text written by Ammianus Marcellius in the 4th Century AD\u201d describing its construction and combat usage.<ref name="catapults.info">{{Citation|url=http://www.catapults.info/ |archive-url=https://web.archive.org/web/20020601094938/http://www.catapults.info/ |url-status=dead |archive-date=2002-06-01 |title=Catapults info }}.</ref>\n:\n; [[Trebuchet]]: [[File:MongolsBesiegingACityInTheMiddleEast13thCentury.jpg|thumb|left|Mongol warriors using trebuchet to besiege a city]] Trebuchets were probably the most powerful catapult employed in the Middle Ages. The most commonly used ammunition were stones, but "darts and sharp wooden poles" could be substituted if necessary. The most effective kind of ammunition though involved fire, such as "firebrands, and deadly [[Greek Fire]]". Trebuchets came in two different designs: Traction, which were powered by people, or Counterpoise, where the people were replaced with "a weight on the short end".<ref name= "Middle Ages"/>  The most famous historical account of trebuchet use dates back to the siege of [[Stirling Castle]] in 1304, when the army of Edward I constructed a giant trebuchet known as [[Warwolf]], which then proceeded to "level a section of [castle] wall, successfully concluding the siege".<ref name="catapults.info" />\n:\n; [[Trebuchet|Couillard]]: A simplified trebuchet, where the trebuchet's single counterweight is split, swinging on either side of a central support post.\n:\n; Leonardo da Vinci's catapult: [[Leonardo da Vinci]] sought to improve the efficiency and range of earlier designs. His design incorporated a large wooden [[leaf spring]] as an [[:wikt:accumulator|accumulator]] to power the catapult.{{citation needed |date=February 2011}} Both ends of the bow are connected by a rope, similar to the design of a [[bow and arrow]]. The leaf spring was not used to pull the catapult armature directly, rather the rope was wound around a drum. The catapult armature was attached to this drum which would be turned until enough potential energy was stored in the deformation of the spring. The drum would then be disengaged from the winding mechanism, and the catapult arm would snap around.{{citation needed | date = February 2011}} Though no records exist of this design being built during Leonardo's lifetime, contemporary enthusiasts have reconstructed it.{{citation needed|date=February 2011}}"}},
{"article_title": "Cryogenics", "pageid": "7176", "revid": "1055671363", "timestamp": "2021-11-17T04:41:04Z", "history_paths": [["Cryogenics --- Introduction ---", "Industrial applications"]], "categories": ["cryogenics", "cooling technology", "industrial gases"], "heading_tree": {"Cryogenics --- Introduction ---": {"Definitions and distinctions": {}, "Etymology": {}, "Cryogenic fluids": {}, "Industrial applications": {"Cryogenic processing": {}, "Fuels": {}}, "Other applications": {}, "Production": {}, "Detectors": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Cryogenics --- Introduction ---|Industrial applications": "{{More citations needed section|date=March 2018}}\n[[Image:Cryogenic carbon steel socket weld globe valve.jpg|70px|thumb|Cryogenic valve]]\n{{Further|Timeline of low-temperature technology}}\n[[Liquefied gas]]es, such as [[liquid nitrogen]] and [[liquid helium]], are used in many cryogenic applications. Liquid nitrogen is the most commonly used element in cryogenics and is legally purchasable around the world. Liquid helium is also commonly used and allows for the [[boiling point|lowest attainable temperatures]] to be reached.\n\nThese liquids may be stored in [[Dewar flask]]s, which are double-walled containers with a high vacuum between the walls to reduce heat transfer into the liquid.  Typical laboratory Dewar flasks are spherical, made of glass and protected in a metal outer container.  Dewar flasks for extremely cold liquids such as liquid helium have another double-walled container filled with liquid nitrogen.  Dewar flasks are named after their inventor, [[James Dewar]], the man who first liquefied [[hydrogen]].  [[Thermos]] bottles are smaller [[vacuum flask]]s fitted in a protective casing.\n\nCryogenic barcode labels are used to mark Dewar flasks containing these liquids, and will not frost over down to \u2212195 degrees Celsius.<ref>{{cite web|last1=Thermal|first1=Timmy|title=Cryogenic Labels|url=http://www.midcomdata.com/cryogenic-labels/|website=MidcomData|access-date=11 August 2014}}</ref>\n\nCryogenic transfer pumps are the pumps used on [[LNG pier]]s to transfer [[liquefied natural gas]] from [[LNG carrier]]s to [[Storage tank|LNG storage tanks]], as are cryogenic valves.\n\n The field of cryogenics advanced during World War II when scientists found that metals frozen to low temperatures showed more resistance to wear.  Based on this theory of [[cryogenic hardening]], the commercial [[cryogenic processor|cryogenic processing]] industry was founded in 1966 by Ed Busch. With a background in the [[heat treatment|heat treating]] industry, Busch founded a company in [[Detroit, Michigan|Detroit]] called CryoTech in 1966 <ref>{{cite book|last1=Gantz|first1=Carroll|title=Refrigeration: A History|date=2015|publisher=McFarland & Company, Inc.|location=Jefferson, North Carolina|isbn=978-0-7864-7687-9|page=227|url=https://books.google.com/books?id=0UgjCgAAQBAJ&q=ed+busch+cryotech&pg=PA227}}</ref> which merged with [http://www.300below.com/ 300 Below] in 1999 to become the world's largest and oldest commercial cryogenic processing company.{{Citation needed|date=February 2013}} Busch originally experimented with the possibility of increasing the life of metal tools to anywhere between 200% and 400% of the original life expectancy using [[cryogenic tempering]] instead of heat treating.{{Citation needed|reason=Materials would re-age at room temperature.|date=March 2015}} This evolved in the late 1990s into the treatment of other parts.\n\nCryogens, such as liquid [[nitrogen]], are further used for specialty chilling and freezing applications.  Some chemical reactions, like those used to produce the active ingredients for the popular [[statin]] drugs, must occur at low temperatures of approximately {{convert|\u2212100|\u00b0C|\u00b0F}}. Special cryogenic [[chemical reactor]]s are used to remove reaction heat and provide a low temperature environment.  The freezing of foods and biotechnology products, like [[vaccine]]s, requires nitrogen in blast freezing or immersion freezing systems. Certain soft or elastic materials become hard and [[brittleness|brittle]] at very low temperatures, which makes cryogenic [[mill (grinding)|milling]] ([[cryomilling]]) an option for some materials that cannot easily be milled at higher temperatures.\n\nCryogenic processing is not a substitute for heat treatment, but rather an extension of the heating\u2013quenching\u2013tempering cycle. Normally, when an item is quenched, the final temperature is ambient. The only reason for this is that most heat treaters do not have cooling equipment. There is nothing metallurgically significant about ambient temperature. The cryogenic process continues this action from ambient temperature down to {{convert|-320|\u00b0F|\u00b0R K \u00b0C|0}}.\nIn most instances the cryogenic cycle is followed by a heat tempering procedure. As all alloys do not have the same chemical constituents, the tempering procedure varies according to the material's chemical composition, thermal history and/or a tool's particular service application.\n\nThe entire process takes 3\u20134 days.\n\n Another use of cryogenics is [[cryogenic fuel]]s for rockets with [[liquid hydrogen]] as the most widely used example. [[Liquid oxygen]] (LOX) is even more widely used but as an [[oxidizer]], not a fuel. [[NASA]]'s workhorse [[Space Shuttle]] used cryogenic hydrogen/oxygen propellant as its primary means of getting into [[orbit]]. LOX is also widely used with [[RP-1]] kerosene, a non-cryogenic hydrocarbon, such as in the rockets built for the [[Soviet space program]] by [[Sergei Korolev]].\n\nRussian aircraft manufacturer [[Tupolev]] developed a version of its popular design [[Tu-154]] with a cryogenic fuel system, known as the [[Tu-155]]. The plane uses a fuel referred to as  [[liquefied natural gas]] or LNG, and made its first flight in 1989."}},
{"article_title": "Common Gateway Interface", "pageid": "7220", "revid": "1062851374", "timestamp": "2021-12-30T22:32:58Z", "history_paths": [["Common Gateway Interface --- Introduction ---", "History"]], "categories": ["servers (computing)", "web 1.0", "web technology", "network protocols", "articles with example python (programming language) code"], "heading_tree": {"Common Gateway Interface --- Introduction ---": {"History": {}, "Purpose of the CGI specification": {}, "Using CGI scripts": {}, "Example": {}, "Deployment": {}, "Uses": {}, "Security": {}, "Alternatives": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Common Gateway Interface --- Introduction ---|History": "[[File:Common Gateway Interface logo.svg|thumbnail|The official CGI logo from the spec announcement]]\nIn 1993 the [[National Center for Supercomputing Applications]] (NCSA) team wrote the specification for calling command line executables on the www-talk mailing list.<ref>{{cite mailing list |url=http://1997.webhistory.org/www.lists/www-talk.1993q4/0485.html |title=Server Scripts |mailing-list=www-talk |date=1993-11-14 |last=McCool |first=Rob |author-link= Robert McCool |df=mdy |access-date=2019-05-15}}</ref><ref>{{cite web |title=The Common Gateway Interface |url=http://hoohoo.ncsa.uiuc.edu/cgi/ |website=Hoohoo [[NCSA HTTPd]] |publisher=[[National Center for Supercomputing Applications|NCSA]] |archive-url=https://web.archive.org/web/20100127161358/http://hoohoo.ncsa.illinois.edu/cgi/ |archive-date=2010-01-27}}</ref><ref>{{cite web |title=CGI: Common Gateway Interface |url=http://www.w3.org/CGI/ |website=[[World Wide Web Consortium|W3C]] |publisher=[[World Wide Web Consortium]] |df=mdy |access-date=2019-05-15}}</ref> The other Web server developers adopted it, and it has been a standard for Web servers ever since. A work group chaired by [[Ken Coar]] started in November 1997 to get the NCSA definition of CGI more formally defined.<ref>{{cite web |url=http://ken.coar.org/cgi/ |title=Common Gateway Interface RFC Project Page |archive-url=https://web.archive.org/web/20130825202222/http://ken.coar.org/cgi/ |archive-date=2013-08-25}}</ref> This work resulted in RFC 3875, which specified CGI Version 1.1. Specifically mentioned in the RFC are the following contributors:<ref name="rfc-3875"/>\n* [[Rob McCool]] (author of the [[NCSA HTTPd]] [[HTTP Server|Web Server]])\n* John Franks (author of the GN Web Server)\n* [[Ari Luotonen]] (the developer of the [[CERN httpd]] Web Server)\n* Tony Sanders (author of the Plexus Web Server)\n* George Phillips (Web server maintainer at the [[University of British Columbia]])\n\nHistorically CGI programs were often written using the C language. RFC 3875 "The Common Gateway Interface (CGI)" partially defines CGI using C,<ref name="rfc-3875"/> in saying that environment variables "are accessed by the C library routine getenv() or variable environ".\n\nThe name CGI comes from the early days of the Web, where ''Web masters'' wanted to connect legacy information systems such as databases to their Web servers. The CGI program was executed by the server that provided a common "gateway" between the Web server and the legacy information system."}},
{"article_title": "Crankshaft", "pageid": "7249", "revid": "1042681479", "timestamp": "2021-09-06T06:33:20Z", "history_paths": [["Crankshaft --- Introduction ---", "History"]], "categories": ["crankshafts", "arab inventions", "engine components", "engine technology", "linkages (mechanical)", "piston engines", "turkish inventions"], "heading_tree": {"Crankshaft --- Introduction ---": {"History": {"Crank mechanism": {"Han China": {}, "Roman Empire": {}, "Medieval Europe": {}}, "Crankshaft": {"Medieval Near East": {}, "Renaissance Europe": {}, "Modern Europe": {}}}, "Internal combustion engines": {"Bearings": {}, "Piston stroke": {}, "Engine configuration": {}, "Engine balance": {}, "Flying arms": {}, "Rotary aircraft engines": {}, "Radial engines": {}}, "Construction": {"Forging and casting, and machining": {}}, "Stress on crankshafts": {}, "Counter-rotating crankshafts": {}, "See also": {}, "References": {}, "Sources": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Crankshaft --- Introduction ---|History": "{{Main|Crank (mechanism)}}\n\n {{Main|Science and technology of the Han dynasty}}\n\n[[File:Bundesarchiv Bild 135-BB-152-11, Tibetexpedition, Tibeter mit Handm\u00fchle.jpg|thumb|upright|[[Tibetan people|Tibetan]] operating a [[Quern-stone|quern]] (1938). The upright handle of such rotary handmills, set at a distance from the centre of rotation, works as a crank.<ref name="Ritti, Grewe, Kessener 2007, 159">{{harvnb|Ritti|Grewe|Kessener|2007|p=159}}</ref><ref name="Lucas 2005, 5, fn. 9">{{harvnb|Lucas|2005|p=5, fn. 9}}</ref>]]\n\nThe earliest hand-operated cranks appeared in [[China]] during the [[Han Dynasty]] (202 BC-220 AD). They were used for silk-reeling, hemp-spinning, for the agricultural [[winnowing]] fan, in the water-powered flour-sifter, for hydraulic-powered metallurgic [[bellows]], and in the well [[windlass]].<ref name="needham volume 4 part 2 118">{{harvnb|Needham|1986|pp=118\u2013119}}</ref> The rotary winnowing fan greatly increased the efficiency of separating grain from husks and stalks.<ref>{{Cite book |title=A Brief Illustrated History of Machines and Mechanisms |last= Bautista Paz |first=Emilio |last2=Ceccarelli |first2=Marco  |last3= Otero |first3=Javier Ech\u00e1varri |last4= Sanz |first4=Jos\u00e9 Luis Mu\u00f1oz |publisher=Springer |year=2010 |isbn=978-9048125111 |publication-date=May 12, 2010 |page=19}}</ref><ref>{{Cite book |title=Understanding China: Dangerous Resentments |last= Du Bois  |first=George |publisher=Trafford on Demand |year= 2014 |isbn=978-1490745077}}</ref> However, the potential of the crank of converting circular motion into reciprocal motion never seems to have been fully realized in China, and the crank was typically absent from such machines until the turn of the 20th century.<ref>{{harvnb|White Jr.|1962|p=104}}: Yet a student of the Chinese technology of the early twentieth century remarks that even a generation ago the Chinese had not 'reached that stage where continuous rotary motion is substituted for reciprocating motion in technical contrivances such as the drill, lathe, saw, etc. To take this step familiarity with the crank is necessary. The crank in its simple rudimentary form we find in the [modern] Chinese windlass, which use of the device, however, has apparently not given the impulse to change reciprocating into circular motion in other contrivances'. In China the crank was known, but remained dormant for at least nineteen centuries, its explosive potential for applied mechanics being unrecognized and unexploited.</ref>\n\n {{Main|Roman technology|List of Roman watermills}}\nA crank in the form of an eccentrically-mounted handle of the rotary [[Quern-stone|handmill]] appeared in 5th century BC [[Celtiberians|Celtiberian]] [[Spain]] and ultimately spread across the [[Roman Empire]].<ref>{{harvnb|Frankel|2003|pp=17\u201319}}</ref><ref name="Ritti, Grewe, Kessener 2007, 159"/><ref name="Lucas 2005, 5, fn. 9"/> A Roman iron crank dating to the 2nd century AD was excavated in [[Augusta Raurica]], [[Switzerland]].<ref name="Schi\u00f6ler 2009, 113">{{harvnb|Schi\u00f6ler|2009|pp=113f.}}</ref><ref>{{harvnb|Laur-Belart|1988|pp=51\u201352, 56, fig. 42}}</ref> The crank-operated [[Roman Empire|Roman]] mill is dated to the late 2nd century.<ref>{{harvnb|Volpert|1997|pp=195, 199}}</ref>\n\n[[File:R\u00f6mische S\u00e4gem\u00fchle.svg|thumb|[[Hierapolis sawmill]] in [[Asia Minor]] (3rd century), a machine that combines a crank with a connecting rod.<ref name="Ritti, Grewe, Kessener 2007, 161"/>]]\n\nEvidence for the crank combined with a connecting rod appears in the [[Hierapolis mill]], dating to the 3rd century; they are also found in stone [[sawmill]]s in [[Roman Syria]] and [[Ephesus]] dating to the 6th century.<ref name="Ritti, Grewe, Kessener 2007, 161">{{harvnb|Ritti|Grewe|Kessener|2007|p=161}}: Because of the findings at Ephesus and Gerasa the invention of the crank and connecting rod system has had to be redated from the 13th to the 6th c; now the Hierapolis relief takes it back another three centuries, which confirms that water-powered stone saw mills were indeed in use when Ausonius wrote his Mosella.</ref> The [[pediment]] of the Hierapolis mill shows a [[waterwheel]] fed by a [[mill race]] powering via a [[gear train]] two [[frame saw]]s which cut blocks by the way of some kind of connecting rods and cranks.<ref>{{harvnb|Ritti|Grewe|Kessener|2007|pp=139\u2013141}}</ref> The crank and connecting rod mechanisms of the other two archaeologically-attested sawmills worked without a gear train.<ref>{{harvnb|Ritti|Grewe|Kessener|2007|pp=149\u2013153}}</ref><ref>{{harvnb|Mangartz|2010|pp=579f.}}</ref> Water-powered [[marble]] saws in [[Germany]] were mentioned by the late 4th century poet [[Ausonius]];<ref name="Ritti, Grewe, Kessener 2007, 161"/> about the same time, these mill types seem also to be indicated by [[Gregory of Nyssa]] from [[Anatolia]].<ref>{{harvnb|Wilson|2002|p=16}}</ref><ref name="Ritti, Grewe, Kessener 2007, 161"/><ref>{{harvnb|Ritti|Grewe|Kessener|2007|p=156, fn. 74}}</ref>\n\n {{Main|Medieval technology|Renaissance technology}}\nA rotary [[Grindstone (tool)|grindstone]]<ref name="White Jr. 1962, 110">{{harvnb|White Jr.|1962|p=110}}</ref> operated by a crank handle is shown in the [[Carolingian dynasty|Carolingian]] manuscript ''[[Utrecht Psalter]]''; the pen drawing of around 830 goes back to a late antique original.<ref>{{harvnb|H\u00e4germann|Schneider|1997|pp=425f.}}</ref> Cranks used to turn wheels are also depicted or described in various works dating from the tenth to thirteenth centuries.<ref name="White Jr. 1962, 110"/><ref>{{harvnb|Needham|1986|pp=112–113}}.</ref>\n\nThe first depictions of the compound crank in the carpenter's [[Brace (tool)|brace]] appear between 1420 and 1430 in northern European artwork.<ref name="White Jr. 1962, 112">{{harvnb|White Jr.|1962|p=112}}</ref> The rapid adoption of the compound crank can be traced in the works of an unknown German engineer writing on the state of military technology during the Hussite Wars: first, the connecting-rod, applied to cranks, reappeared; second, double-compound cranks also began to be equipped with connecting-rods; and third, the flywheel was employed for these cranks to get them over the 'dead-spot'.<ref name="White Jr. 1962, 113">{{harvnb|White Jr.|1962|p=113}}</ref> The concept was much improved by the Italian engineer and writer [[Roberto Valturio]] in 1463, who devised a boat with five sets, where the parallel cranks are all joined to a single power source by one connecting-rod, an idea also taken up by his compatriot Italian painter [[Francesco di Giorgio]].<ref name="White Jr. 1962, 114">{{harvnb|White Jr.|1962|p=114}}</ref>\n\nThe crank had become common in Europe by the early 15th century, as seen in the works of the military engineer [[Konrad Kyeser]] (1366–after 1405).<ref name="needham volume 4 part 2 113">{{harvnb|Needham|1986|p=113}}.</ref><ref name="White Jr. 1962, 111"/> Devices depicted in Kyeser's ''[[Bellifortis]]'' include cranked windlasses for spanning siege crossbows, cranked chain of buckets for water-lifting and cranks fitted to a wheel of bells.<ref name="White Jr. 1962, 111"/> Kyeser also equipped the [[Archimedes' screw]]s for water-raising with a crank handle, an innovation which subsequently replaced the ancient practice of working the pipe by treading.<ref>{{harvnb|White Jr.|1962|pp=105, 111, 168}}</ref>\n\n[[Pisanello]] painted a piston-pump driven by a water-wheel and operated by two simple cranks and two connecting-rods.<ref name="White Jr. 1962, 113"/>\n\nThe 15th also century saw the introduction of cranked rack-and-pinion devices, called cranequins, which were fitted to the [[crossbow]]'s stock as a means of exerting even more force while spanning the missile weapon.<ref>{{harvnb|Hall|1979|pp=74f.}}</ref> In the textile industry, cranked [[reel]]s for winding skeins of yarn were introduced.<ref name="White Jr. 1962, 111">{{harvnb|White Jr.|1962|p=111}}</ref>\n\n \n The non-manual crank appears in several of the hydraulic devices described by the [[Ban\u016b M\u016bs\u0101]] brothers in their 9th-century ''[[Book of Ingenious Devices]]''.<ref>{{citation|title=The Cambridge History of Arabic Literature|last=A. F. L. Beeston, M. J. L. Young|first=J. D. Latham, Robert Bertram Serjeant|publisher=[[Cambridge University Press]]|year=1990|isbn=0-521-32763-6|page=266}}</ref> These automatically operated cranks appear in several devices, two of which contain an action which approximates to that of a crankshaft, anticipating [[Al-Jazari]]'s invention by several centuries and its first appearance in Europe by over five centuries. However, the automatic crank described by the Banu Musa would not have allowed a full rotation, but only a small modification was required to convert it to a crankshaft.<ref name="Hill1979">{{citation|title=The book of ingenious devices (Kit\u0101b al-\u1e25iyal)|author=[[Banu Musa]] (authors), [[Donald Routledge Hill]] (translator)|publisher=[[Springer Science+Business Media|Springer]]|year=1979|isbn=90-277-0833-9|pages=23\u20134}}</ref>\n\nArab engineer [[Al-Jazari]] (1136–1206), in the [[Artuqids|Artuqid Sultanate]], described a crank and connecting rod system in a rotating machine in two of his water-raising machines.<ref name=Crank>[[Ahmad Y Hassan]]. [http://www.history-science-technology.com/Notes/Notes%203.htm The Crank-Connecting Rod System in a Continuously Rotating Machine].</ref> The author Sally Ganchy identified a crankshaft in his twin-cylinder [[pump]] mechanism,<ref name="Sally Ganchy 2009 41">{{citation|title=Islam and Science, Medicine, and Technology|last=Sally Ganchy|first=Sarah Gancher|publisher=The Rosen Publishing Group|year=2009|isbn=978-1-4358-5066-8|page=41|url-access=registration|url=https://archive.org/details/islamsciencemedi0000ganc}}</ref> including both the crank and [[Shaft (mechanical engineering)|shaft]] mechanisms.<ref name="books.google.co.uk">[[Donald Hill]] (2012), [https://books.google.co.uk/books?id=EUTqCAAAQBAJ&pg=PA273 ''The Book of Knowledge of Ingenious Mechanical Devices'', page 273], [[Springer Science + Business Media]]</ref> According to historian [[Donald Routledge Hill]], Al-Jazari invented the crankshaft.<ref name="Hill1979"/>\n\n [[File:Anonymous of the Hussite Wars. Clm 197, Part 1, Folio 17v Supra.jpg|thumb|left|15th century paddle-wheel boat whose paddles are turned by single-throw crankshafts (Anonymous of the [[Hussite Wars]])]]\n\nThe Italian physician [[Guido da Vigevano]] (c. 1280\u22121349), planning for a new crusade, made illustrations for a [[Paddle steamer#History|paddle boat]] and war carriages that were propelled by manually turned compound cranks and gear wheels,<ref>{{harvnb|Hall|1979|p=80}}</ref> identified as an early crankshaft prototype by [[Lynn Townsend White]].<ref>{{cite book|title=Medieval Religion and Technology: Collected Essays|page=335|last1=Townsend White|first1=Lynn|year=1978|publisher=University of California Press|isbn=9780520035669|url-access=registration|url=https://archive.org/details/medievalreligion00whit}}</ref> The ''[[Luttrell Psalter]]'', dating to around 1340, describes a grindstone which was rotated by two cranks, one at each end of its axle; the geared hand-mill, operated either with one or two cranks, appeared later in the 15th century.<ref name="White Jr. 1962, 111"/>\n\n[[File:Fotothek df tg 0006690 Mechanik ^ Wasserf\u00f6rderung ^ Pumpe.jpg|thumb|left|upright|Water-raising pump powered by crank and connecting rod mechanism ([[Georg Andreas B\u00f6ckler]], 1661)]]\n\nAround 1480, the early medieval rotary grindstone was improved with a treadle and crank mechanism. Cranks mounted on push-carts first appear in a German engraving of 1589.<ref>{{harvnb|White Jr.|1962|p=167}}</ref> Crankshafts were also described by [[Leonardo da Vinci]] (1452\u20131519)<ref name=Crank/> and a Dutch farmer and windmill owner by the name [[Cornelis Corneliszoon van Uitgeest]] in 1592. His wind-powered [[sawmill]] used a crankshaft to convert a windmill's circular motion into a back-and-forward motion powering the saw. Corneliszoon was granted a [[patent]] for his crankshaft in 1597.\n\n From the 16th century onwards, evidence of cranks and connecting rods integrated into machine design becomes abundant in the technological treatises of the period: [[Agostino Ramelli]]'s ''The Diverse and Artifactitious Machines'' of 1588 depicts eighteen examples, a number that rises in the ''Theatrum Machinarum Novum'' by [[Georg Andreas B\u00f6ckler]] to 45 different machines.<ref>{{harvnb|White Jr.|1962|p=172}}</ref> Cranks were formerly common on some machines in the early 20th century; for example almost all [[phonograph]]s before the 1930s were powered by [[clockwork]] motors wound with cranks. Reciprocating piston engines use cranks to convert the linear piston motion into rotational motion. [[Internal combustion engine]]s of early 20th century [[automobile]]s were usually started with hand cranks, before [[Automobile self starter|electric starters]] came into general use. The 1918 [[REO Motor Car Company|Reo]] owner's manual describes how to hand crank the automobile:\n\n* First: Make sure the gear shifting lever is in neutral position.\n* Second: The clutch pedal is unlatched and the clutch engaged. The brake pedal is pushed forward as far as possible setting brakes on the rear wheel.\n* Third: See that spark control lever, which is the short lever located on top of the steering wheel on the right side, is back as far as possible toward the driver and the long lever, on top of the steering column controlling the carburetor, is pushed forward about one inch from its retarded position.\n* Fourth: Turn ignition switch to point marked "B" or "M"\n* Fifth: Set the carburetor control on the steering column to the point marked "START." Be sure there is gasoline in the carburetor. Test for this by pressing down on the small pin projecting from the front of the bowl until the carburetor floods. If it fails to flood it shows that the fuel is not being delivered to the carburetor properly and the motor cannot be expected to start. See instructions on page 56 for filling the vacuum tank.\n* Sixth: When it is certain the carburetor has a supply of fuel, grasp the handle of starting crank, push in endwise to engage ratchet with crank shaft pin and turn over the motor by giving a quick upward pull. Never push down, because if for any reason the motor should kick back, it would endanger the operator."}},
{"article_title": "Capability Maturity Model", "pageid": "7492", "revid": "1012741504", "timestamp": "2021-03-18T01:54:05Z", "history_paths": [["Capability Maturity Model --- Introduction ---", "History"]], "categories": ["software development process", "maturity models", "information technology management"], "heading_tree": {"Capability Maturity Model --- Introduction ---": {"Overview": {}, "History": {"Prior need for software processes": {}, "Precursor": {}, "Development at Software Engineering Institute": {}, "Capability Maturity Model Integration": {}, "Adapted to other processes": {}}, "Model topics": {"Maturity models": {}, "Structure": {}, "Levels": {}, "Critique": {}, "Software process framework": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Capability Maturity Model --- Introduction ---|History": "{{Synthesis|section|date=August 2016}}\n\n In the 1980s, the use of computers grew more widespread, more flexible and less costly. Organizations began to adopt computerized information systems, and the demand for [[software development]] grew significantly. Many processes for software development were in their infancy, with few standard or "[[best practice]]" approaches defined.\n\nAs a result, the growth was accompanied by growing pains: project failure was common, the field of [[computer science]] was still in its early years, and the ambitions for project scale and complexity exceeded the market capability to deliver adequate products within a planned budget. Individuals such as [[Edward Yourdon]],<ref name=yourdon89msa>{{cite book\n |last1=Yourdon\n |first1=E.\n |title=1989. Modern Structured Analysis.\n |location=New York\n |publisher=[[Prentice Hall.]]\n |year=1989\n |isbn=978-0135986240\n |url-access=registration\n |url=https://archive.org/details/modernstructured00your\n }}</ref> [[Larry Constantine]], [[Gerald Weinberg]],<ref name=weinberg92qsm>{{cite book\n |last1=Weinberg |first1=G. M. |author-link1=Gerald M. Weinberg\n |title=Quality Software Management: Anticipating Change. Vol. 1: Systems Thinking.\n |location=New York\n |publisher=[[Dorset House Pub.]]\n |year=1992\n |isbn=978-0-932633-72-9\n}}</ref> [[Tom DeMarco]],<ref name=demarcolister97wwb>{{cite book\n |last1=DeMarco |first1=T. |last2=Lister |first2=T.\n |title=Waltzing with Bears: Managing Risk on Software Projects\n |location=New York\n |publisher=[[Dorset House Pub.]]\n |year=1997\n |isbn= 978-0-932633-60-6\n}}</ref> and [[David Parnas]] began to publish articles and books with research results in an attempt to professionalize the software-development processes.<ref name="McKay"/><ref>{{Cite news|url=http://pep-inc.com/2011/01/23/cmmi-six-sigma-their-roots/|title=CMMI-Six Sigma, their roots|date=2011-01-23|work=Process Enhancement Partners, Inc.|access-date=2018-05-11|language=en-US}}</ref>\n\nIn the 1980s, several US military projects involving software subcontractors ran over-budget and were completed far later than planned, if at all. In an effort to determine why this was occurring, the [[United States Air Force]] funded a study at the Software Engineering Institute (SEI).\n\n \nThe first application of a staged maturity model to IT was not by CMU/SEI, but rather by [[Richard L. Nolan]], who, in 1973 published the [[stages of growth model]] for IT organizations.<ref>{{Cite journal | last1 = Nolan | first1 = R. L. | title = Managing the computer resource: A stage hypothesis | doi = 10.1145/362280.362284 | journal = [[Communications of the ACM|Comm. ACM]] | volume = 16 | issue = 7 | pages = 399\u2013405 | date=July 1973 | s2cid = 14053595 }}</ref>\n\n[[Watts Humphrey]] began developing his process maturity concepts during the later stages of his 27-year career at IBM.<ref>{{Cite web|url=http://resources.sei.cmu.edu/library/asset-view.cfm?assetid=5329|title=People Capability Maturity Model (P-CMM) Version 2.0|website=resources.sei.cmu.edu|access-date=2017-01-17}}</ref>\n\n Active development of the model by the US Department of Defense Software Engineering Institute (SEI) began in 1986 when Humphrey joined the [[Software Engineering Institute]] located at Carnegie Mellon University in [[Pittsburgh, Pennsylvania]] after retiring from IBM. At the request of the U.S. Air Force he began formalizing his Process Maturity Framework to aid the U.S. Department of Defense in evaluating the capability of software contractors as part of awarding contracts.\n\nThe result of the Air Force study was a model for the military to use as an objective evaluation of software subcontractors' process capability maturity. Humphrey based this framework on the earlier [[Quality Management Maturity Grid]] developed by [[Philip B. Crosby]] in his book "Quality is Free".<ref name=crosby79qif>{{cite book\n |last1=Crosby |first1=P. B. |author-link1=Philip B. Crosby\n |title=Quality is Free\n |url=https://archive.org/details/qualityisfreeart00cros |url-access=registration |location=New York\n |publisher=[[New American Library]]\n |year=1979\n |isbn=0-451-62247-2\n}}</ref> Humphrey's approach differed because of his unique insight that organizations mature their processes in stages based on solving process problems in a specific order. Humphrey based his approach on the staged evolution of a system of software development practices within an organization, rather than measuring the maturity of each separate development process independently. The CMM has thus been used by different organizations as a general and powerful tool for understanding and then improving general business process performance.\n\nWatts Humphrey's Capability Maturity Model (CMM) was published in 1988<ref>{{Cite journal | last1 = Humphrey | first1 = W. S. | author-link1 = Watts Humphrey | title = Characterizing the software process: A maturity framework | doi = 10.1109/52.2014 | journal = [[IEEE Software]] | volume = 5 | issue = 2 | pages = 73\u201379 | date=March 1988 | s2cid = 1008347 | url = http://www.sei.cmu.edu/reports/87tr011.pdf }}</ref> and as a book in 1989, in ''Managing the Software Process''.<ref name=watts89msp>{{cite book\n |last1=Humphrey |first1=W. S. |author-link1=Watts Humphrey\n |title=Managing the Software Process\n |year=1989\n |location=Reading, Mass.\n |publisher=[[Addison-Wesley]]\n |series=SEI series in software engineering\n |isbn=0-201-18095-2\n}}</ref>\n\nOrganizations were originally assessed using a process maturity questionnaire and a Software Capability Evaluation method devised by Humphrey and his colleagues at the Software Engineering Institute.\n\nThe full representation of the Capability Maturity Model as a set of defined process areas and practices at each of the five maturity levels was initiated in 1991, with Version 1.1 being completed in January 1993.<ref name="sei93cmm"/> The CMM was published as a book<ref>{{Cite book |last1=Paulk |first1=Mark C. |last2=Weber |first2=Charles V |last3=Curtis |first3=Bill |author3-link=Dr Bill Curtis |last4=Chrissis |first4=Mary Beth |title=The Capability Maturity Model: Guidelines for Improving the Software Process |place=Reading, Mass. |publisher=[[Addison-Wesley]] |series=SEI series in software engineering |year=1995 |isbn=0-201-54664-7 |url-access=registration |url=https://archive.org/details/capabilitymaturi00paul }}</ref> in 1995 by its primary authors, Mark C. Paulk, Charles V. Weber, [[Dr Bill Curtis|Bill Curtis]], and Mary Beth Chrissis.\nUnited States of America\nNew York, USA.\n\n The CMM model's application in software development has sometimes been problematic. Applying multiple models that are not integrated within and across an organization could be costly in training, appraisals, and improvement activities. The [[Capability Maturity Model Integration]] (CMMI) project was formed to sort out the problem of using multiple models for software development processes, thus the CMMI model has superseded the CMM model, though the CMM model continues to be a general theoretical process capability model used in the public domain.<ref>{{Cite book|url=https://books.google.com/books?id=NJ0Apk1iNDAC&q=The+Capability+Maturity+Model+Integration+%28CMMI%29+project+was+formed+to+sort+out+the+problem+of+using+multiple+models+for+software+development+processes%2C+thus+the+CMMI+model+has+superseded+the+CMM+model%2C+though+the+CMM+model+continues+to+be+a+general+theoretical+process+capability+model+used+in+the+public+domain&pg=PA486|title=Juran'S Quality Hb 6E|last=Juran|date=2010-08-26|publisher=McGraw-Hill Education (India) Pvt Limited|isbn=9780071070898|language=en}}</ref>{{Citation needed|date=March 2012}}<ref>{{Cite book|title=Proceedings of the International Conference on Transformations in Engineering Education|last=Natarajan|first=R|publisher=Springer|year=2015}}</ref>\n\n The CMM was originally intended as a tool to evaluate the ability of government contractors to perform a contracted software project. Though it comes from the area of software development, it can be, has been, and continues to be widely applied as a general model of the maturity of ''process'' (e.g., [[IT service management]] processes) in IS/IT (and other) organizations."}},
{"article_title": "Cable car (railway)", "pageid": "7674", "revid": "1062731620", "timestamp": "2021-12-30T05:25:42Z", "history_paths": [["Cable car (railway) --- Introduction ---", "History"]], "categories": ["cable railways", "cable car railways", "rail technologies", "railways by type", "articles containing video clips"], "heading_tree": {"Cable car (railway) --- Introduction ---": {"History": {"Recent revival": {}}, "Operation": {}, "Relation to funiculars": {}, "List of cable car systems": {"Cities currently operating cable cars": {"Traditional cable car systems": {}, "Modern cable car systems": {}}, "Cities previously operating cable cars": {"Australia": {}, "Colombia": {}, "France": {}, "Lebanon": {}, "New Zealand": {}, "Philippines": {}, "Portugal": {}, "United Kingdom": {}, "Isle of Man": {}, "United States": {}}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cable car (railway) --- Introduction ---|History": "[[File:Minories stationLBR.jpg|thumb|left|Winding drums on the [[London and Blackwall Railway|London and Blackwall]] cable-operated railway, 1840]]\n\n[[File:Cable Driving Plant, Designed and Constructed by Poole and Hunt, Baltimore, MD.jpg|thumb|Cable Driving Plant, Designed and Constructed by Poole & Hunt, Baltimore, MD. Drawing by P.F. Goist, circa 1882. The powerhouse has two horizontal single-cylinder engines. The lithograph shows a hypothetical prototype of a cable powerhouse, rather than any actual built structure.<ref>{{cite book|last=Hilton|first=George W.|title=The Cable Car in America|year=1971|publisher=Howell NorthBooks|location=Berkeley, CA.}}</ref> Poole & Hunt, machinists and engineers, was a major cable industry designer and contractor and manufacturer of gearing, sheaves, shafting and wire rope drums. They did work for cable railways in Baltimore, Chicago, Hoboken, Kansas City, New York, and Philadelphia.<ref>{{cite news|title=The Cable in Chicago: Speeding along the Streets Rapid Transit there for Miles|newspaper=The Baltimore Sun, page 8|date=Nov 9, 1889}}</ref>]]\n\nThe first cable-operated railway, employing a moving rope that could be picked up or released by a grip on the cars was the [[Fawdon Wagonway]] in 1826, a [[colliery railway line]].<ref>Erskine Hazard, Observations upon Rail-roads, [https://books.google.com/books?id=yrgFAAAAYAAJ&pg=PA275 The Franklin Journal and American Mechanics' Magazine], Vol. III, No. 4 (April 1827); page 275.</ref><ref>Fawdon Wagonway, [http://sine.ncl.ac.uk/view_structure_information.asp?struct_id=722 Structural Images of the North East] {{webarchive|url=https://web.archive.org/web/20120902001020/http://sine.ncl.ac.uk/view_structure_information.asp?struct_id=722 |date=2012-09-02 }}, University of Newcastle upon Tyne, 26 Mar. 2004.</ref>  The [[London and Blackwall Railway]], which opened for passengers in east [[London]], England, in 1840 used such a system.<ref>{{cite journal|last=Robertson|first=Andrew|date=March 1848|title=Blackwall Railway Machinery|journal=The Civil Engineer and Architect's Journal|publisher=Wiley & Putnam|location=New York|volume=11}}</ref> The rope available at the time proved too susceptible to wear and the system was abandoned in favour of [[steam locomotive]]s after eight years. In America, the first cable car installation in operation probably was the [[IRT Ninth Avenue Line|West Side and Yonkers Patent Railway]] in [[New York City]], as its first-ever [[elevated railway]] which ran from 1 July 1868 to 1870. The cable technology used in this elevated railway involved collar-equipped cables and claw-equipped cars, proving cumbersome. The line was closed and rebuilt, reopening with [[steam locomotive]]s.\n\nIn 1869 [[P. G. T. Beauregard]] demonstrated a cable car at [[New Orleans]]<ref name="St. Charles Streetcar">{{Cite book |title=St. Charles Streetcar, The: Or, the New Orleans & Carrollton Railroad |author=James Guilbeau |date =2011 |publisher =Pelican Publishing Company |isbn=9781879714021 |pages =48\u201349 }}</ref><ref name="The Streetcars of New Orleans">{{Cite book |title=The Streetcars of New Orleans |author=Louis C. Hennick |author2=Elbridge Harper Charlton |date = 1965 |publisher =Pelican Publishing |isbn=9781455612598 |page =16 }}</ref><ref>{{Cite web |url=https://www.asme.org/getmedia/40ef6e7c-697d-4f77-8daa-059a37f698b3/101-St-Charles-Avenue-Streetcar-Line-1835.aspx |title=St. Charles Avenue Streetcar Line, 1835 |access-date=2016-03-29 |archive-url=https://web.archive.org/web/20161220072405/https://www.asme.org/getmedia/40ef6e7c-697d-4f77-8daa-059a37f698b3/101-St-Charles-Avenue-Streetcar-Line-1835.aspx |archive-date=2016-12-20 |url-status=dead }}</ref> and was issued {{US patent|97343}}.\n\nOther cable cars to use grips were those of the [[Clay Street Hill Railroad]], which later became part of the [[San Francisco cable car system]]. The building of this line was promoted by [[Andrew Smith Hallidie]] with design work by [[William Eppelsheimer]], and it was first tested in 1873. The success of these grips ensured that this line became the model for other cable car transit systems, and this model is often known as the ''Hallidie Cable Car''.\n\nIn 1881 the [[Dunedin cable tramway system]] opened in [[Dunedin]], [[New Zealand]] and became the first such system outside San Francisco. For Dunedin, [[George Smith Duncan]] further developed the Hallidie model, introducing the pull curve and the slot brake; the former was a way to pull cars through a curve, since Dunedin's curves were too sharp to allow coasting, while the latter forced a wedge down into the cable slot to stop the car. Both of these innovations were generally adopted by other cities, including San Francisco.\n\nIn Australia, the [[Melbourne cable tramway system]] operated from 1885 to 1940. It was one of the most extensive in the world with 1200 trams and trailers operating over 15 routes with 103 km (64 miles) of track. Sydney also had a couple of cable tram routes.\n\nCable cars rapidly spread to other cities, although the major attraction for most was the ability to displace [[horsecar]] (or [[mule]]-drawn) systems rather than the ability to climb hills. Many people at the time viewed horse-drawn transit as unnecessarily cruel, and the fact that a typical horse could work only four or five hours per day necessitated the maintenance of large [[stables]] of [[draft animals]] that had to be fed, housed, groomed, medicated and rested. Thus, for a period, economics worked in favour of cable cars even in relatively flat cities.\n\nFor example, the [[Chicago City Railway]], also designed by Eppelsheimer, opened in [[Chicago]] in 1882 and went on to become the largest and most profitable [[Cable cars in Chicago|cable car system]]. As with many cities, the problem in flat Chicago was not one of incline, but of transportation capacity. This caused a different approach to the combination of grip car and trailer. Rather than using a grip car and single trailer, as many cities did, or combining the grip and trailer into a single car, like San Francisco's ''California Cars'', Chicago used grip cars to pull trains of up to three trailers.\n\nIn 1883 the [[New York and Brooklyn Bridge Railway]] was opened, which had a most curious feature: though it was a cable car system, it used [[steam locomotive]]s to get the cars into and out of the terminals. After 1896 the system was changed to one on which a motor car was added to each train to maneuver at the terminals, while en route, the trains were still propelled by the cable.\n\n[[File:Cablecarpicjpg.jpg|thumb|right|A San Francisco cable car travels along California Street in the city's Financial District.]]\n\nOn 25 September 1883, a test of a cable car system was held by [[Liverpool Tramways Company]] in [[Kirkdale, Liverpool|Kirkdale]], [[Liverpool]]. This would have been the first cable car system in Europe, but the company decided against implementing it. Instead, the distinction went to the 1884 [[Highgate Hill Cable Tramway]], a route from [[Archway, London|Archway]] to [[Highgate]], north London, which used a continuous cable and grip system on the 1 in 11 (9%) climb of Highgate Hill. The installation was not reliable and was replaced by electric traction in 1909.<ref>{{cite book |last=Taylor |first=Sheila |title=The Moving Metropolis |publisher=Calmann and King |location=London |year=2001 |page=82 |isbn=1-85669-241-8}}</ref> Other cable car systems were implemented in Europe, though, among which was the [[Glasgow Subway|Glasgow District Subway]], the first underground cable car system, in 1896. ([[London]], England's first deep-level tube railway, the [[City & South London Railway]], had earlier also been built for cable haulage but had been converted to electric traction before opening in 1890.) A few more cable car systems were built in the [[United Kingdom]], [[Trams in Lisbon|Portugal]], and [[Belleville funicular tramway|France]]. European cities, having many more curves in their streets, were ultimately less suitable for cable cars than American cities.\n\nThough some new cable car systems were still being built, by 1890 the cheaper to construct and simpler to operate [[electricity|electrically]]-powered [[tram|trolley]] or tram started to become the norm, and eventually started to replace existing cable car systems. For a while hybrid cable/electric systems operated, for example in Chicago where electric cars had to be pulled by grip cars through the loop area, due to the lack of trolley wires there. Eventually, San Francisco became the only street-running manually operated system to survive\u2014Dunedin, the second city with such cars, was also the second-last city to operate them, closing down in 1957.\n\n In the last decades of the 20th-century, cable traction in general has seen a limited revival as [[people mover|automatic people movers]], used in resort areas, airports (for example, [[Link Train|Toronto Airport]]), huge hospital centers and some urban settings. While many of these systems involve cars permanently attached to the cable, the [[Minimetro]] system from [[Poma]]/[[Leitner Group]] and the [[Cable Liner]] system from [[DCC Doppelmayr Cable Car]] both have variants that allow the cars to be automatically decoupled from the cable under computer control, and can thus be considered a modern interpretation of the cable car."}},
{"article_title": "DNA", "pageid": "7955", "revid": "1060707694", "timestamp": "2021-12-17T05:26:36Z", "history_paths": [["DNA --- Introduction ---", "History"]], "categories": ["dna", "helices", "biotechnology", "nucleic acids"], "heading_tree": {"DNA --- Introduction ---": {"Properties": {"Nucleobase classification": {}, "Non-canonical bases": {}, "Listing of non-canonical bases found in DNA": {}, "Grooves": {}, "Base pairing": {"ssDNA vs. dsDNA": {}}, "Sense and antisense": {}, "Supercoiling": {}, "Alternative DNA structures": {}, "Alternative DNA chemistry": {}, "Quadruplex structures": {}, "Branched DNA": {}, "Artificial bases": {}}, "Chemical modifications and altered DNA packaging": {"Base modifications and DNA packaging": {}, "Damage": {}}, "Biological functions": {"Genes and genomes": {}, "Transcription and translation": {}, "Replication": {}, "Extracellular nucleic acids": {}, "Neutrophil extracellular traps": {}}, "Interactions with proteins": {"DNA-binding proteins": {}, "DNA-modifying enzymes": {"Nucleases and ligases": {}, "Topoisomerases and helicases": {}, "Polymerases": {}}}, "Genetic recombination": {}, "Evolution": {}, "Uses in technology": {"Genetic engineering": {}, "DNA profiling": {}, "DNA enzymes or catalytic DNA": {}, "Bioinformatics": {}, "DNA nanotechnology": {}, "History and anthropology": {}, "Information storage": {}}, "History": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"DNA --- Introduction ---|History": "{{further|History of molecular biology}}\n[[File:Maclyn McCarty with Francis Crick and James D Watson - 10.1371 journal.pbio.0030341.g001-O.jpg|thumb|[[Maclyn McCarty]]  (left) shakes hands with [[Francis Crick]] and [[James Watson]], co-originators of the double-helix model.]]\n[[File:Pencil sketch of the DNA double helix by Francis Crick Wellcome L0051225.jpg|thumb|right|Pencil sketch of the DNA double helix by Francis Crick in 1953]]\nDNA was first isolated by the Swiss physician [[Friedrich Miescher]] who, in 1869, discovered a microscopic substance in the [[pus]] of discarded surgical bandages. As it resided in the nuclei of cells, he called it "nuclein".<ref>{{cite journal | last = Miescher | first = Friedrich | name-list-style = vanc | year = 1871 | url = https://books.google.com/books?id=YJRTAAAAcAAJ&pg=PA441 | title = Ueber die chemische Zusammensetzung der Eiterzellen | language = de | trans-title = On the chemical composition of pus cells | journal = Medicinisch-chemische Untersuchungen | volume = 4 | pages = 441\u201360 | quote = [p. 456] ''Ich habe mich daher sp\u00e4ter mit meinen Versuchen an die ganzen Kerne gehalten, die Trennung der K\u00f6rper, die ich einstweilen ohne weiteres Pr\u00e4judiz als l\u00f6sliches und unl\u00f6sliches Nuclein bezeichnen will, einem g\u00fcnstigeren Material \u00fcberlassend.'' (Therefore, in my experiments I subsequently limited myself to the whole nucleus, leaving to a more favorable material the separation of the substances, that for the present, without further prejudice, I will designate as soluble and insoluble nuclear material ("Nuclein"))}}</ref><ref>{{cite journal | vauthors = Dahm R | s2cid = 915930 | title = Discovering DNA: Friedrich Miescher and the early years of nucleic acid research | journal = Human Genetics | volume = 122 | issue = 6 | pages = 565\u201381 | date = January 2008 | pmid = 17901982 | doi = 10.1007/s00439-007-0433-0 }}</ref> In 1878, [[Albrecht Kossel]] isolated the non-protein component of "nuclein", nucleic acid, and later isolated its five primary [[nucleobase]]s.<ref>See:\n* {{cite journal | vauthors = Kossel A | year = 1879 | url = https://books.google.com/books?id=4H5NAAAAYAAJ&pg=PA284 | title = Ueber Nucle\u00efn der Hefe | language = de| trans-title = On nuclein in yeast | journal = Zeitschrift f\u00fcr physiologische Chemie | volume = 3 | pages = 284\u201391 }}\n* {{cite journal | vauthors = Kossel A | year = 1880 | url = https://books.google.com/books?id=u4s1AQAAMAAJ&pg=PA290 | title = Ueber Nucle\u00efn der Hefe II | language = de | trans-title = On nuclein in yeast, Part 2 | journal = Zeitschrift f\u00fcr physiologische Chemie | volume = 4 | pages = 290\u201395 }}\n* {{cite journal | vauthors = Kossel A | year = 1881 | url = https://books.google.com/books?id=xYs1AQAAMAAJ&pg=PA267 | title = Ueber die Verbreitung des Hypoxanthins im Thier- und Pflanzenreich | language = de | trans-title = On the distribution of hypoxanthins in the animal and plant kingdoms | journal = Zeitschrift f\u00fcr physiologische Chemie | volume = 5 | pages = 267\u201371 }}\n* {{cite book | vauthors = Kossel A | title = Untersuchungen \u00fcber die Nucleine und ihre Spaltungsprodukte | language = de | trans-title = Investigations into nuclein and its cleavage products | location = Strassburg, Germany | veditors = Tr\u00fcbne KJ | year = 1881 | pages = 19 }}\n* {{cite journal | vauthors = Kossel A | year = 1882 | url = https://books.google.com/books?id=z4s1AQAAMAAJ&pg=PA422 | title = Ueber Xanthin und Hypoxanthin |trans-title= On xanthin and hypoxanthin | journal = Zeitschrift f\u00fcr physiologische Chemie | volume = 6 | pages = 422\u201331 }}\n* Albrect Kossel (1883) [https://books.google.com/books?id=2os1AQAAMAAJ&pg=PA7#v=onepage "Zur Chemie des Zellkerns"] {{webarchive|url=https://web.archive.org/web/20171117235430/https://books.google.com/books?id=2os1AQAAMAAJ&pg=PA7 |date=17 November 2017 }} (On the chemistry of the cell nucleus), ''Zeitschrift f\u00fcr physiologische Chemie'', '''7''' : 7\u201322.\n* {{cite journal | vauthors = Kossel A | year = 1886 | title = Weitere Beitr\u00e4ge zur Chemie des Zellkerns | language = de | trans-title = Further contributions to the chemistry of the cell nucleus | journal = Zeitschrift f\u00fcr Physiologische Chemie | volume = 10 | pages = 248\u201364 | url = http://vlp.mpiwg-berlin.mpg.de/library/data/lit16615/index_html?pn=1&ws=1.5 | quote = On p. 264, Kossel remarked presciently: Der Erforschung der quantitativen Verh\u00e4ltnisse der vier stickstoffreichen Basen, der Abh\u00e4ngigkeit ihrer Menge von den physiologischen Zust\u00e4nden der Zelle, verspricht wichtige Aufschl\u00fcsse \u00fcber die elementaren physiologisch-chemischen Vorg\u00e4nge. (The study of the quantitative relations of the four nitrogenous bases\u2014[and] of the dependence of their quantity on the physiological states of the cell\u2014promises important insights into the fundamental physiological-chemical processes.) }}</ref><ref name="Yale_Jones_1953">{{cite journal | vauthors = Jones ME | title = Albrecht Kossel, a biographical sketch | journal = The Yale Journal of Biology and Medicine | volume = 26 | issue = 1 | pages = 80\u201397 | date = September 1953 | pmid = 13103145 | pmc = 2599350 }}</ref>\n\nIn 1909, [[Phoebus Levene]] identified the base, sugar, and phosphate nucleotide unit of the RNA (then named "yeast nucleic acid").<ref>{{cite journal | vauthors = Levene PA, Jacobs WA | year = 1909 | title = \u00dcber Inosins\u00e4ure | language = de | journal = Berichte der Deutschen Chemischen Gesellschaft | volume = 42 | pages = 1198\u2013203 |url=https://babel.hathitrust.org/cgi/pt?id=iau.31858002459620&view=1up&seq=1054 | doi=10.1002/cber.190904201196}}</ref><ref>{{cite journal | vauthors = Levene PA, Jacobs WA | year = 1909 | title = \u00dcber die Hefe-Nucleins\u00e4ure | language = de | journal = Berichte der Deutschen Chemischen Gesellschaft | volume = 42 | issue = 2 | pages = 2474\u201378 | doi=10.1002/cber.190904202148| url = https://zenodo.org/record/2175598 }}</ref><ref>{{cite journal | vauthors = Levene P |title=The structure of yeast nucleic acid| journal=J Biol Chem |volume=40 |issue=2 |pages=415\u201324 |year=1919|doi=10.1016/S0021-9258(18)87254-4|doi-access=free }}</ref> In 1929, Levene identified deoxyribose sugar in "thymus nucleic acid" (DNA).<ref>{{cite journal | vauthors = Cohen JS, Portugal FH | year = 1974 | title = The search for the chemical structure of DNA | journal = Connecticut Medicine | volume = 38 | issue = 10 | pages = 551\u201352, 554\u201357 | pmid = 4609088 | url = https://profiles.nlm.nih.gov/ps/access/CCAAHW.pdf }}</ref> Levene suggested that DNA consisted of a string of four nucleotide units linked together through the phosphate groups ("tetranucleotide hypothesis"). Levene thought the chain was short and the bases repeated in a fixed order.\nIn 1927, [[Nikolai Koltsov]] proposed that inherited traits would be inherited via a "giant hereditary molecule" made up of "two mirror strands that would replicate in a semi-conservative fashion using each strand as a template".<ref>Koltsov proposed that a cell's genetic information was encoded in a long chain of amino acids. See:\n* {{cite speech | first = \u041d. \u041a. | last = \u041a\u043e\u043b\u044c\u0446\u043e\u0432 | title = \u0424\u0438\u0437\u0438\u043a\u043e-\u0445\u0438\u043c\u0438\u0447\u0435\u0441\u043a\u0438\u0435 \u043e\u0441\u043d\u043e\u0432\u044b \u043c\u043e\u0440\u0444\u043e\u043b\u043e\u0433\u0438\u0438 | trans-title = The physical-chemical basis of morphology | language = ru | event = 3rd All-Union Meeting of Zoologist, Anatomists, and Histologists | location = Leningrad, U.S.S.R. | date = 12 December 1927 }}\n* Reprinted in: {{cite journal | first = \u041d. \u041a. | last = \u041a\u043e\u043b\u044c\u0446\u043e\u0432 | title = \u0424\u0438\u0437\u0438\u043a\u043e-\u0445\u0438\u043c\u0438\u0447\u0435\u0441\u043a\u0438\u0435 \u043e\u0441\u043d\u043e\u0432\u044b \u043c\u043e\u0440\u0444\u043e\u043b\u043e\u0433\u0438\u0438 | trans-title = The physical-chemical basis of morphology | language = ru| journal = \u0423\u0441\u043f\u0435\u0445\u0438 \u044d\u043a\u0441\u043f\u0435\u0440\u0438\u043c\u0435\u043d\u0442\u0430\u043b\u044c\u043d\u043e\u0439 \u0431\u0438\u043e\u043b\u043e\u0433\u0438\u0438 (Advances in Experimental Biology) series B | volume = 7 | issue = 1 | pages = ? | date = 1928 }}\n* Reprinted in German as: {{cite journal | first = Nikolaj K. | last = Koltzoff | name-list-style = vanc | date = 1928 | title = Physikalisch-chemische Grundlagen der Morphologie | trans-title = The physical-chemical basis of morphology | language = de | journal = Biologisches Zentralblatt | volume = 48 | issue = 6 | pages = 345\u201369 }}\n* In 1934, Koltsov contended that the proteins that contain a cell's genetic information replicate. See: {{cite journal | vauthors = Koltzoff N | title = The structure of the chromosomes in the salivary glands of Drosophila | journal = Science | volume = 80 | issue = 2075 | pages = 312\u201313 | date = October 1934 | pmid = 17769043 | doi = 10.1126/science.80.2075.312 | quote = From page 313: "I think that the size of the chromosomes in the salivary glands [of Drosophila] is determined through the multiplication of ''genonemes''. By this term I designate the axial thread of the chromosome, in which the geneticists locate the linear combination of genes; \u2026 In the normal chromosome there is usually only one genoneme; before cell-division this genoneme has become divided into two strands."| bibcode = 1934Sci....80..312K }}</ref><ref name="Soyfer">{{cite journal | vauthors = Soyfer VN | s2cid = 46277758 | title = The consequences of political dictatorship for Russian science | journal = Nature Reviews Genetics | volume = 2 | issue = 9 | pages = 723\u201329 | date = September 2001 | pmid = 11533721 | doi = 10.1038/35088598 }}</ref> In 1928, [[Frederick Griffith]] in his [[Griffith's experiment|experiment]] discovered that [[trait (biology)|traits]] of the "smooth" form of ''Pneumococcus'' could be transferred to the "rough" form of the same bacteria by mixing killed "smooth" bacteria with the live "rough" form.<ref>{{cite journal | vauthors = Griffith F | title = The Significance of Pneumococcal Types | journal = The Journal of Hygiene | volume = 27 | issue = 2 | pages = 113\u201359 | date = January 1928 | pmid = 20474956 | pmc = 2167760 | doi = 10.1017/S0022172400031879 }}</ref><ref>{{cite journal | vauthors = Lorenz MG, Wackernagel W | title = Bacterial gene transfer by natural genetic transformation in the environment | journal = Microbiological Reviews | volume = 58 | issue = 3 | pages = 563\u2013602 | date = September 1994 | pmid = 7968924 | pmc = 372978 | doi = 10.1128/MMBR.58.3.563-602.1994 }}</ref> This system provided the first clear suggestion that DNA carries genetic information.\n\nIn 1933, while studying virgin [[sea urchin]] eggs, [[Jean Brachet]] suggested that DNA is found in the [[cell nucleus]] and that [[RNA]] is present exclusively in the [[cytoplasm]]. At the time, "yeast nucleic acid" (RNA) was thought to occur only in plants, while "thymus nucleic acid" (DNA) only in animals. The latter was thought to be a tetramer, with the function of buffering cellular pH.<ref>{{cite journal | vauthors = Brachet J | year = 1933 | title = Recherches sur la synthese de l'acide thymonucleique pendant le developpement de l'oeuf d'Oursin | language = it | journal = Archives de Biologie | volume = 44 | pages = 519\u201376 }}</ref><ref>{{cite book | vauthors = Burian R | year = 1994 | chapter = Jean Brachet's Cytochemical Embryology: Connections with the Renovation of Biology in France? | veditors = Debru C, Gayon J, Picard JF | title = Les sciences biologiques et m\u00e9dicales en France 1920\u20131950 | volume = 2 | series = Cahiers pour I'histoire de la recherche | location = Paris | publisher = CNRS Editions | pages = 207\u201320 | chapter-url = http://www.histcnrs.fr/ColloqDijon/Burian-Brachet.pdf }}</ref>\n\nIn 1937, [[William Astbury]] produced the first X-ray diffraction patterns that showed that DNA had a regular structure.<ref>See:\n* {{cite journal | vauthors = Astbury WT, Bell FO | year = 1938 | title = Some recent developments in the X-ray study of proteins and related structures | journal = Cold Spring Harbor Symposia on Quantitative Biology | volume = 6 | pages = 109\u201321 | url = http://www.leeds.ac.uk/heritage/Astbury/bibliography/CSHSQB_Astbury_and_Bell_1938.pdf | archive-url = https://web.archive.org/web/20140714204539/http://www.leeds.ac.uk/heritage/Astbury/bibliography/CSHSQB_Astbury_and_Bell_1938.pdf | archive-date = 14 July 2014 | doi=10.1101/sqb.1938.006.01.013}}\n* {{cite journal | vauthors = Astbury WT | title = X-ray studies of nucleic acids | journal = Symposia of the Society for Experimental Biology | issue = 1 | pages = 66\u201376 | year = 1947 | pmid = 20257017 | url = http://scarc.library.oregonstate.edu/coll/pauling/dna/papers/astbury-xray.html | archive-url = https://web.archive.org/web/20140705132403/http://scarc.library.oregonstate.edu/coll/pauling/dna/papers/astbury-xray.html | archive-date=5 July 2014 }}</ref>\n\nIn 1943, [[Oswald Avery]], along with co-workers [[Colin Munro MacLeod|Colin MacLeod]] and [[Maclyn McCarty]], identified DNA as the [[Griffith's experiment|transforming principle]], supporting Griffith's suggestion ([[Avery\u2013MacLeod\u2013McCarty experiment]]).<ref>{{cite journal | vauthors = Avery OT, Macleod CM, McCarty M | title = Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III | journal = The Journal of Experimental Medicine | volume = 79 | issue = 2 | pages = 137\u201358 | date = February 1944 | pmid = 19871359 | pmc = 2135445 | doi = 10.1084/jem.79.2.137 }}</ref> [[Erwin Chargaff]] developed and published observations now known as [[Chargaff's rules]], stating that in DNA from any species of any organism, the amount of [[guanine]] should be equal to [[cytosine]] and the amount of [[adenine]] should be equal to [[thymine]].<ref name="chargaff_1950">{{cite journal |last1=Chargaff |first1=Erwin |title=Chemical specificity of nucleic acids and mechanism of their enzymatic degradation |journal=Experientia |date=June 1950 |volume=6 |issue=6 |pages=201\u2013209 |doi=10.1007/BF02173653|pmid=15421335 |s2cid=2522535 }}</ref><ref name="kresge_2005">{{cite journal |last1=Kresge |first1=Nicole |last2=Simoni |first2=Robert D. |last3=Hill |first3=Robert L. |title=Chargaff's Rules: the Work of Erwin Chargaff |journal=Journal of Biological Chemistry |date=June 2005 |volume=280 |issue=24 |pages=172\u2013174 |doi=10.1016/S0021-9258(20)61522-8|doi-access=free }}</ref> Late in 1951, [[Francis Crick]] started working with [[James Watson]] at the [[Cavendish Laboratory]] within the [[University of Cambridge]]. DNA's role in [[heredity]] was confirmed in 1952 when [[Alfred Hershey]] and [[Martha Chase]] in the [[Hershey\u2013Chase experiment]] showed that DNA is the [[genetic material]] of the [[enterobacteria phage T2]].<ref>{{cite journal | vauthors = Hershey AD, Chase M | title = Independent functions of viral protein and nucleic acid in growth of bacteriophage | journal = The Journal of General Physiology | volume = 36 | issue = 1 | pages = 39\u201356 | date = May 1952 | pmid = 12981234 | pmc = 2147348 | doi = 10.1085/jgp.36.1.39 }}</ref>\n\n[[File:TheEaglePub-Cambridge-BluePlaque.jpg|thumb|left|A [[blue plaque]] outside [[The Eagle, Cambridge|The Eagle]] [[pub]] commemorating Crick and Watson]]  In May 1952, [[Raymond Gosling]], a graduate student working under the supervision of [[Rosalind Franklin]], took an [[X-ray diffraction]] image, labeled as "[[Photo 51]]",<ref>The B-DNA X-ray pattern [http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/dna/pictures/sci9.001.5.html on the right of this linked image] {{webarchive|url=https://archive.today/20120525030457/http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/dna/pictures/sci9.001.5.html |date=25 May 2012 }}</ref> at high hydration levels of DNA. This photo was given to Watson and Crick by [[Maurice Wilkins]] and was critical to their obtaining the correct structure of DNA. Franklin told Crick and Watson that the backbones had to be on the outside. Before then, Linus Pauling, and Watson and Crick, had erroneous models with the chains inside and the bases pointing outwards. Franklin's identification of the [[space group]] for DNA crystals revealed to Crick that the two DNA strands were [[Antiparallel (biochemistry)|antiparallel]].<ref name="ReferenceA">{{cite book|last=Schwartz|first=James | name-list-style = vanc |title=In pursuit of the gene : from Darwin to DNA|url=https://archive.org/details/inpursuitofgenef00schw|url-access=registration|year=2008|publisher=Harvard University Press|location=Cambridge, Mass.|isbn=9780674026704 }}</ref>\nIn February 1953, [[Linus Pauling]] and [[Robert Corey]] proposed a model for nucleic acids containing three intertwined chains, with the phosphates near the axis, and the bases on the outside.<ref name="pmid16578429">{{cite journal | vauthors = Pauling L, Corey RB | title = A Proposed Structure For The Nucleic Acids | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 39 | issue = 2 | pages = 84\u201397 | date = February 1953 | pmid = 16578429 | pmc = 1063734 | doi = 10.1073/pnas.39.2.84| url = http://scarc.library.oregonstate.edu/coll/pauling/dna/papers/1953p.9-084.html | bibcode = 1953PNAS...39...84P | doi-access = free }}</ref> \nWatson and Crick completed their model, which is now accepted as the first correct model of the double-helix of [[Molecular structure of Nucleic Acids|DNA]]. On 28 February 1953 Crick interrupted patrons' lunchtime at [[The Eagle, Cambridge|The Eagle]] [[pub]] in Cambridge to announce that he and Watson had "discovered the secret of life".<ref>{{cite book | last = Regis | first = Ed | name-list-style = vanc | date = 2009 | title = What Is Life?: investigating the nature of life in the age of synthetic biology | location = Oxford | publisher = [[Oxford University Press]] | isbn = 978-0-19-538341-6 | page = 52 }}</ref>\n\nThe 25 April 1953 issue of the journal ''Nature'' published a series of five articles giving the Watson and Crick double-helix structure DNA and evidence supporting it.<ref name=NatureDNA50>{{cite web | work = Nature Archives | url = http://www.nature.com/nature/dna50/archive.html | title = Double Helix of DNA: 50 Years | archive-url = https://web.archive.org/web/20150405140401/http://www.nature.com/nature/dna50/archive.html | archive-date=5 April 2015 | url-status=dead }}</ref> The structure was reported in a letter titled "''MOLECULAR STRUCTURE OF NUCLEIC ACIDS A  Structure for Deoxyribose Nucleic Acid''", in which they said, "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."<ref name="autogenerated2" /> This letter was followed by a letter from Franklin and Gosling, which was the first publication of their own X-ray diffraction data and of their original analysis method.<ref name=NatFranGos/><ref>{{cite web | url = http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/dna/pictures/franklin-typeBphoto.html | title = Original X-ray diffraction image | publisher = Oregon State Library | access-date = 6 February 2011 | url-status=live | archive-url = https://web.archive.org/web/20090130111849/http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/dna/pictures/franklin-typeBphoto.html | archive-date=30 January 2009 }}</ref> Then followed a letter by Wilkins and two of his colleagues, which contained an analysis of ''in vivo'' B-DNA X-ray patterns, and which supported the presence ''in vivo'' of the Watson and Crick structure.<ref name="NatWilk" />\n\nIn 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the [[Nobel Prize in Physiology or Medicine]].<ref>{{cite web | url = http://nobelprize.org/nobel_prizes/medicine/laureates/1962/ | title = The Nobel Prize in Physiology or Medicine 1962 | work = Nobelprize.org }}</ref> Nobel Prizes are awarded only to living recipients. A debate continues about who should receive credit for the discovery.<ref>{{cite journal | vauthors = Maddox B | s2cid = 4428347 | title = The double helix and the 'wronged heroine' | journal = Nature | volume = 421 | issue = 6921 | pages = 407\u201308 | date = January 2003 | pmid = 12540909 | doi = 10.1038/nature01399 | url = http://www.biomath.nyu.edu/index/course/hw_articles/nature4.pdf | bibcode = 2003Natur.421..407M | url-status=live | archive-url = https://web.archive.org/web/20161017011403/http://www.biomath.nyu.edu/index/course/hw_articles/nature4.pdf | archive-date = 17 October 2016 | df = dmy-all | doi-access = free }}</ref>\n\nIn an influential presentation in 1957, Crick laid out the [[central dogma of molecular biology]], which foretold the relationship between DNA, RNA, and proteins, and articulated the "adaptor hypothesis".<ref>{{cite speech |last= Crick |first= F.H.C. | name-list-style = vanc |title=A Note for the RNA Tie Club | date= 1955 | location = Cambridge, England |url= http://genome.wellcome.ac.uk/assets/wtx030893.pdf | archive-url = https://web.archive.org/web/20081001223217/http://genome.wellcome.ac.uk/assets/wtx030893.pdf | url-status=dead | archive-date = 1 October 2008 }}</ref> Final confirmation of the replication mechanism that was implied by the double-helical structure followed in 1958 through the [[Meselson\u2013Stahl experiment]].<ref>{{cite journal | vauthors = Meselson M, Stahl FW | title = The Replication of DNA in Escherichia Coli | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 44 | issue = 7 | pages = 671\u201382 | date = July 1958 | pmid = 16590258 | pmc = 528642 | doi = 10.1073/pnas.44.7.671 | bibcode = 1958PNAS...44..671M | doi-access = free }}</ref> Further work by Crick and co-workers showed that the genetic code was based on non-overlapping triplets of bases, called [[Genetic code#Codons|codons]], allowing [[Har Gobind Khorana]], [[Robert W. Holley]], and [[Marshall Warren Nirenberg]] to decipher the genetic code.<ref>{{cite web | url = http://nobelprize.org/nobel_prizes/medicine/laureates/1968/ | title = The Nobel Prize in Physiology or Medicine 1968 | work = Nobelprize.org }}</ref> These findings represent the birth of [[molecular biology]].<ref>{{cite journal | vauthors = Pray L | year = 2008 | title = Discovery of DNA structure and function: Watson and Crick. | journal = Nature Education | volume = 1 | issue = 1 | pages = 100 }}</ref>\n{{clear}}"}},
{"article_title": "Data warehouse", "pageid": "7990", "revid": "1062824276", "timestamp": "2021-12-30T19:21:35Z", "history_paths": [["Data warehouse --- Introduction ---", "History"]], "categories": ["business intelligence", "data management", "data warehousing", "information technology management"], "heading_tree": {"Data warehouse --- Introduction ---": {"ETL-based data warehousing": {}, "ELT-based data warehousing": {}, "Benefits": {}, "Generic": {}, "Related systems (data mart, OLAPS, OLTP, predictive analytics)": {}, "History": {}, "Information storage": {"Facts": {}, "Dimensional versus normalized approach for storage of data": {"Dimensional approach": {}, "Normalized approach": {}}}, "Design methods": {"Bottom-up design": {}, "Top-down design": {}, "Hybrid design": {}}, "Data warehouse characteristics": {"Subject-oriented": {}, "Integrated": {}, "Time-variant": {}, "Nonvolatile": {}}, "Data warehouse options": {"Aggregation": {}}, "Data warehouse architecture": {}, "Versus operational system": {}, "Evolution in organization use": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Data warehouse --- Introduction ---|History": "The concept of data warehousing dates back to the late 1980s<ref>{{cite web |url=http://www.computerworld.com/databasetopics/data/story/0,10801,70102,00.html |title=The Story So Far |date=2002-04-15 |access-date=2008-09-21 |url-status=dead |archive-url=https://web.archive.org/web/20080708182105/http://www.computerworld.com/databasetopics/data/story/0%2C10801%2C70102%2C00.html |archive-date=2008-07-08 }}</ref> when IBM researchers Barry Devlin and Paul Murphy developed the "business data warehouse". In essence, the data warehousing concept was intended to provide an architectural model for the flow of data from operational systems to [[decision support system|decision support environments]]. The concept attempted to address the various problems associated with this flow, mainly the high costs associated with it. In the absence of a data warehousing architecture, an enormous amount of redundancy was required to support multiple decision support environments. In larger corporations, it was typical for multiple decision support environments to operate independently. Though each environment served different users, they often required much of the same stored data. The process of gathering, cleaning and integrating data from various sources, usually from long-term existing operational systems (usually referred to as [[legacy system]]s), was typically in part replicated for each environment. Moreover, the operational systems were frequently reexamined as new decision support requirements emerged. Often new requirements necessitated gathering, cleaning and integrating new data from "[[data mart]]s" that was tailored for ready access by users.\n\nAdditionally, with the publication of The IRM Imperative (Wiley & Sons, 1991) by James M. Kerr, the idea of managing and putting a dollar value on an organization's data resources and then reporting that value as an asset on a balance sheet became popular. In the book, Kerr described a way to populate subject-area databases from data derived from transaction-driven systems to create a storage area where summary data could be further leveraged to inform executive decision-making. This concept served to promote further thinking of how a data warehouse could be developed and managed in a practical way within any enterprise.\n\nKey developments in early years of data warehousing:\n\n* 1960s \u2013 [[General Mills]] and [[Dartmouth College]], in a joint research project, develop the terms ''dimensions'' and ''facts''.<ref name="kimball16">Kimball 2013, pg. 15</ref>\n* 1970s \u2013 [[ACNielsen]] and IRI provide dimensional data marts for retail sales.<ref name="kimball16" />\n* 1970s \u2013 [[Bill Inmon]] begins to define and discuss the term Data Warehouse.{{citation needed|date=June 2014}}\n* 1975 \u2013 [[Sperry Univac]] introduces [[MAPPER]] (MAintain, Prepare, and Produce Executive Reports), a database management and reporting system that includes the world's first [[Fourth-generation programming language|4GL]]. It is the first platform designed for building Information Centers (a forerunner of contemporary data warehouse technology).\n* 1983 \u2013 [[Teradata]] introduces the [[DBC 1012|DBC/1012]] database computer specifically designed for decision support.<ref>{{Cite news |title= Will Teradata revive a market? |author= Paul Gillin |pages= 43, 48 |work= Computer World |date= February 20, 1984 |url= https://books.google.com/books?id=5pw6ePUC8YYC&pg=PA48 |access-date= 2017-03-13 }}</ref>\n* 1984 \u2013 [[Metaphor Computer Systems]], founded by [[David Liddle]] and Don Massaro, releases a hardware/software package and GUI for business users to create a database management and analytic system.\n* 1988 \u2013 Barry Devlin and Paul Murphy publish the article "An architecture for a business and information system" where they introduce the term "business data warehouse".<ref>{{cite journal|title=An architecture for a business and information system|journal=IBM Systems Journal | doi=10.1147/sj.271.0060|volume=27|pages=60\u201380|year=1988|last1=Devlin|first1=B. A.|last2=Murphy|first2=P. T.}}</ref>\n* 1990 \u2013 Red Brick Systems, founded by [[Ralph Kimball]], introduces Red Brick Warehouse, a database management system specifically for data warehousing.\n* 1991 - James M. Kerr authors The IRM Imperative, which suggests data resources could be reported as an asset on a balance sheet, furthering commercial interest in the establishment of data warehouses.\n* 1991 \u2013 Prism Solutions, founded by [[Bill Inmon]], introduces Prism Warehouse Manager, software for developing a data warehouse.\n* 1992 \u2013 [[Bill Inmon]] publishes the book ''Building the Data Warehouse''.<ref>{{cite book|last=Inmon|first=Bill|title=Building the Data Warehouse|year=1992|publisher=Wiley|isbn=0-471-56960-7|url=https://archive.org/details/buildingdataware00inmo_1}}</ref>\n* 1995 \u2013 The Data Warehousing Institute, a for-profit organization that promotes data warehousing, is founded.\n* 1996 \u2013 [[Ralph Kimball]] publishes the book ''The Data Warehouse Toolkit''.<ref name=":0">{{cite book|title=The Data Warehouse Toolkit|last=Kimball|first=Ralph|publisher=Wiley|year=2011|isbn=978-0-470-14977-5|page=237}}</ref>\n* 2000 \u2013 [[Dan Linstedt]] releases in the public domain the [[Data vault modeling]], conceived in 1990 as an alternative to Inmon and Kimball to provide long-term historical storage of data coming in from multiple operational systems, with emphasis on tracing, auditing and resilience to change of the source data model.\n* 2008 \u2013 [[Bill Inmon]], along with Derek Strauss and Genia Neushloss, publishes "DW 2.0: The Architecture for the Next Generation of Data Warehousing", explaining his top-down approach to data warehousing and coining the term, data-warehousing 2.0.\n* 2012 \u2013 [[Bill Inmon]] develops and makes public technology known as "textual disambiguation". Textual disambiguation applies context to raw text and reformats the raw text and context into a standard data base format. Once raw text is passed through textual disambiguation, it can easily and efficiently be accessed and analyzed by standard business intelligence technology. Textual disambiguation is accomplished through the execution of textual ETL. Textual disambiguation is useful wherever raw text is found, such as in documents, Hadoop, email, and so forth."}},
{"article_title": "Dysprosium", "pageid": "8102", "revid": "1055209305", "timestamp": "2021-11-14T15:02:24Z", "history_paths": [["Dysprosium --- Introduction ---", "History"]], "categories": ["dysprosium", "chemical elements", "lanthanides", "energy development", "ferromagnetic materials", "reducing agents", "renewable energy technology"], "heading_tree": {"Dysprosium --- Introduction ---": {"Characteristics": {"Physical properties": {}, "Chemical properties": {}, "Compounds": {}, "Isotopes": {}}, "History": {}, "Occurrence": {}, "Production": {}, "Applications": {}, "Precautions": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Dysprosium --- Introduction ---|History": "In 1878, [[erbium]] ores were found to contain the oxides of [[holmium]] and [[thulium]]. French chemist [[Paul \u00c9mile Lecoq de Boisbaudran]], while working with [[holmium oxide]], separated dysprosium oxide from it in [[Paris]] in 1886.<ref name="DeKosky">{{cite journal|title = Spectroscopy and the Elements in the Late Nineteenth Century: The Work of Sir William Crookes|first = Robert K.|last = DeKosky|journal = The British Journal for the History of Science|volume = 6|issue = 4|date = 1973|pages = 400\u2013423|jstor = 4025503|doi = 10.1017/S0007087400012553}}</ref><ref>{{cite journal|journal = Comptes Rendus|volume = 143|pages = 1003\u20131006|url = http://gallica.bnf.fr/ark:/12148/bpt6k3058f/f1001.chemindefer|title = L'holmine (ou terre X de M Soret) contient au moins deux radicaux m\u00e9tallique (Holminia contains at least two metal)|language = fr|year = 1886|author = de Boisbaudran, Paul \u00c9mile Lecoq}}</ref> His procedure for isolating the dysprosium involved dissolving dysprosium oxide in acid, then adding ammonia to precipitate the hydroxide. He was only able to isolate dysprosium from its oxide after more than 30 attempts at his procedure. On succeeding, he named the element ''dysprosium'' from the Greek ''dysprositos'' (\u03b4\u03c5\u03c3\u03c0\u03c1\u03cc\u03c3\u03b9\u03c4\u03bf\u03c2), meaning "hard to get". The element was not isolated in relatively pure form until after the development of ion exchange techniques by [[Frank Spedding]] at [[Iowa State University]] in the early 1950s.<ref name="nbb">{{cite book|last = Emsley| first = John| title = Nature's Building Blocks| publisher = Oxford University Press| year = 2001| location = Oxford|url=https://books.google.com/books?id=j-Xu07p3cKwC&pg=PA131|pages = 129\u2013132| isbn = 978-0-19-850341-5}}</ref><ref name="Weeks">{{cite book |last1=Weeks |first1=Mary Elvira |title=The discovery of the elements |date=1956 |publisher=Journal of Chemical Education |location=Easton, PA |url=https://archive.org/details/discoveryoftheel002045mbp |edition=6th }}</ref>\n\nDue to its role in permanent magnets used for wind turbines, it has been argued{{By whom|date=August 2021}} that dysprosium will be one of the main objects of geopolitical competition in a world running on renewable energy. But this perspective has been criticised for failing to recognise that most wind turbines do not use permanent magnets and for underestimating the power of economic incentives for expanded production.<ref>{{Cite journal|last=Overland|first=Indra|date=2019-03-01|title=The geopolitics of renewable energy: Debunking four emerging myths|journal=Energy Research & Social Science|volume=49|pages=36\u201340|doi=10.1016/j.erss.2018.10.018|issn=2214-6296|doi-access=free}}</ref><ref name="Klinger">{{cite book |last1=Klinger |first1=Julie Michelle |title=Rare earth frontiers : from terrestrial subsoils to lunar landscapes |date=2017 |publisher=Cornell University Press |location=Ithaca, NY |isbn=978-1501714603 |jstor=10.7591/j.ctt1w0dd6d }}</ref>\n\nIn 2021, Dy was turned into a 2-dimensional [[supersolid]] quantum gas.<ref>{{Cite journal|last1=Norcia|first1=Matthew A.|last2=Politi|first2=Claudia|last3=Klaus|first3=Lauritz|last4=Poli|first4=Elena|last5=Sohmen|first5=Maximilian|last6=Mark|first6=Manfred J.|last7=Bisset|first7=Russell N.|last8=Santos|first8=Luis|last9=Ferlaino|first9=Francesca|date=August 2021|title=Two-dimensional supersolidity in a dipolar quantum gas|url=https://www.nature.com/articles/s41586-021-03725-7|journal=Nature|language=en|volume=596|issue=7872|pages=357\u2013361|doi=10.1038/s41586-021-03725-7|pmid=34408330|arxiv=2102.05555|bibcode=2021Natur.596..357N|s2cid=231861397|issn=1476-4687}}</ref>"}},
{"article_title": "Digital data", "pageid": "8276", "revid": "1063089476", "timestamp": "2022-01-01T04:59:35Z", "history_paths": [["Digital data --- Introduction ---", "Historical digital systems"]], "categories": ["digital media", "digital systems", "digital technology", "consumer electronics"], "heading_tree": {"Digital data --- Introduction ---": {"Symbol to digital conversion": {}, "States": {}, "Properties of digital information": {}, "Historical digital systems": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Digital data --- Introduction ---|Historical digital systems": "Even though digital signals are generally associated with the binary electronic digital systems used in modern electronics and computing, digital systems are actually ancient, and need not be binary or electronic.\n* [[DNA]] [[genetic code]] is a naturally occurring form of digital data storage.\n* Written text (due to the limited character set and the use of discrete symbols \u2013 the alphabet in most cases)\n* The ''[[abacus]]'' was created sometime between 1000 BC and 500 BC, it later became a form of calculation frequency. Nowadays it can be used as a very advanced, yet basic digital calculator that uses beads on rows to represent numbers. Beads only have meaning in discrete up and down states, not in analog in-between states.\n* A ''[[beacon]]'' is perhaps the simplest non-electronic digital signal, with just two states (on and off). In particular, ''[[smoke signal]]s'' are one of the oldest examples of a digital signal, where an analog "carrier" (smoke) is [[modulated]] with a blanket to generate a digital signal (puffs) that conveys information.\n* [[Morse code]] uses six digital states\u2014dot, dash, intra-character gap (between each dot or dash), short gap (between each letter), medium gap (between words), and long gap (between sentences)\u2014to send messages via a variety of potential carriers such as electricity or light, for example using an [[electrical telegraph]] or a flashing light.\n* The [[Braille]] uses a six-bit code rendered as dot patterns.\n* [[Flag semaphore]] uses rods or flags held in particular positions to send messages to the receiver watching them some distance away.\n* [[International maritime signal flags]] have distinctive markings that represent letters of the alphabet to allow ships to send messages to each other.\n* More recently invented, a [[modem]] modulates an analog "carrier" signal (such as sound) to encode binary electrical digital information, as a series of binary digital sound pulses. A slightly earlier, surprisingly reliable version of the same concept was to bundle a sequence of audio digital "signal" and "no signal" information (i.e. "sound" and "silence") on [[compact audio cassette|magnetic cassette tape]] for use with early [[home computer]]s."}},
{"article_title": "Distillation", "pageid": "8301", "revid": "1062970720", "timestamp": "2021-12-31T13:41:27Z", "history_paths": [["Distillation --- Introduction ---", "History"]], "categories": ["distillation", "unit operations", "alchemical processes", "separation processes", "laboratory techniques", "phase transitions", "gas technologies", "ancient inventions"], "heading_tree": {"Distillation --- Introduction ---": {"History": {}, "Applications": {}, "Idealized model": {"Batch or differential distillation": {}, "Continuous distillation": {}, "General improvements": {}}, "Laboratory procedures": {"Simple distillation": {}, "Fractional distillation": {}, "Steam distillation": {}, "Vacuum distillation": {}, "Short path and molecular distillation": {}, "Air-sensitive vacuum distillation": {}, "Zone distillation": {}, "Other types": {}}, "Azeotropic process": {"Breaking an azeotrope with unidirectional pressure manipulation": {}, "Pressure-swing distillation": {}}, "Industrial process": {"Multi-effect distillation": {}}, "In food processing": {"Beverages": {}}, "Gallery": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Distillation --- Introduction ---|History": "{{See also|Distilled beverage}}\n[[File:Zosimos distillation equipment.jpg|thumb|Distillation equipment used by the 3rd century alchemist [[Zosimos of Panopolis]],<ref>{{cite book|page=203|url=https://books.google.com/books?id=earQAAAAMAAJ|title=The Volatile Oils|author1=Gildemeister, E. |author2=Hoffman, Fr. |author3=translated by Edward Kremers |volume=1|location=New York|publisher=Wiley|year=1913}}</ref><ref>{{cite book|page=[https://archive.org/details/isbn_9780618221233/page/88 88]|title=The History of Science and Technology|author1=Bryan H. Bunch|author2=Alexander Hellemans|publisher=Houghton Mifflin Harcourt|year=2004|isbn=978-0-618-22123-3|url-access=registration|url=https://archive.org/details/isbn_9780618221233/page/88}}</ref> from the [[Byzantine Greek]] manuscript ''Parisinus graces.''<ref>[[Marcelin Berthelot|Berthelot, Marcelin]] (1887\u20131888) [https://archive.org/details/collectiondesanc01bert ''Collection des anciens alchimistes grecs'']. 3 vol., Paris, p. 161</ref>]]\n\nEarly evidence of distillation was found on [[Akkadian language|Akkadian]] tablets dated c. 1200 BCE describing perfumery operations. The tablets provided textual evidence that an early primitive form of distillation was known to the [[Babylonia]]ns of ancient [[Mesopotamia]].<ref>{{cite book |last=Levey |first=Martin |title=Chemistry and Chemical Technology in Ancient Mesopotamia |date=1959 |publisher=[[Elsevier]] |page=36 |url=https://books.google.com/books?id=76ILAQAAIAAJ |quote=As already mentioned, the textual evidence for Sumero-Babylonian distillation is disclosed in a group of Akkadian tablets describing perfumery operations, dated ca. 1200 B.C.}}</ref> Early evidence of distillation was also found related to [[Alchemy|alchemists]] working in [[Alexandria, Egypt|Alexandria]] in [[Roman Egypt]] in the 1st century CE.<ref name="Forbes" />{{rp|pp=57,89}}\n\nDistillation was practiced in the ancient [[Indian subcontinent]], which is evident from baked clay [[retort]]s and receivers found at [[Taxila]], [[Shaikhan Dheri]], and [[Charsadda]] in modern [[Pakistan]], dating to the early centuries of the [[Common Era]].<ref>[[John Marshall (archaeologist)|John Marshall]], ''Taxila'', '''2''':[https://books.google.com/books?id=IOnUugEACAAJ&newbks=0&lpg=PP1&vq=water-condensers&pg=PA420 420], 1951</ref><ref>Frank Raymond Allchin, "India: the ancient home of distillation?" ''Man'', New Series '''14''':1:55-63 (1979) [https://www.samorini.it/doc1/alt_aut/ad/allchin-india-the-ancient-home-of-distillation.pdf full text]</ref><ref>Javed Husain, "The So-Called 'Distillery' at Shaikhan Dheri - A Case Study", ''Journal of the Pakistan Historical Society'' '''41''':3:289-314 (Jul 1, 1993)</ref> These "[[Gandhara]] stills" were only capable of producing very weak [[liquor]], as there was no efficient means of collecting the vapors at low heat.<ref name="habib">[[Irfan Habib|Habib, Irfan]] (2011), [https://books.google.com/books?id=K8kO4J3mXUAC&pg=PA55 ''Economic History of Medieval India, 1200\u20131500'']. [[Pearson Education]]. p. 55. {{ISBN|9788131727911}}</ref>  [[Distilled water]] has been in use since at least c. 200 CE, when [[Alexander of Aphrodisias]] described the process.<ref name=Taylor>{{cite journal|last1=Taylor|first1=F.|title=The evolution of the still|journal=Annals of Science|volume=5|page=185|year=1945|doi=10.1080/00033794500201451|issue=3}}</ref><ref>{{cite journal |first=M. P. E. M. |last=Berthelot |date=1893 |title=The Discovery of Alcohol and Distillation |journal=The Popular Science Monthly |volume=XLIII |url=https://books.google.com/books?id=IisDAAAAMBAJ&pg=PA85 |pages=85\u201394 |url-status=live |archive-url=https://web.archive.org/web/20171129151553/https://books.google.com/books?id=IisDAAAAMBAJ&pg=PA85 |archive-date=29 November 2017 |df=dmy-all }}</ref> Work on distilling other liquids continued in early [[Byzantine Egypt]] under [[Zosimus of Panopolis]] in the 3rd century. \n\nDistillation in China may have begun during the [[Eastern Han]] dynasty (1st\u20132nd centuries CE), but the distillation of beverages began in the [[Jin dynasty (1115\u20131234)|Jin]] (12th\u201313th centuries) and [[Southern Song dynasty|Southern Song]] (10th\u201313th centuries) dynasties, according to archaeological evidence.<ref name="Haw">{{cite book|author=Haw, Stephen G.|title=Marco Polo in China|chapter=Wine, women and poison|chapter-url=https://books.google.com/books?id=DSfvfr8VQSEC&pg=PA148|date=2012|publisher=Routledge|isbn=978-1-134-27542-7|pages=147\u2013148|quote=The earliest possible period seems to be the Eastern Han dynasty ... the most likely period for the beginning of true distillation of spirits for drinking in China is during the Jin and Southern Song dynasties}}</ref>\n\nMedieval [[Alchemy and chemistry in the medieval Islamic world|Muslim chemists]] such as [[Jabir ibn Hayyan|J\u0101bir ibn \u1e24ayy\u0101n]] (Latin: Geber, ninth century) and [[Abu Bakr al-Razi|Ab\u016b Bakr al-R\u0101z\u012b]] (Latin: Rhazes, {{circa|865\u2013925}}) experimented extensively with the distillation of various substances.\n\nThe distillation of wine is attested in Arabic works attributed to [[Al-Kindi|al-Kind\u012b]] (c. 801\u2013873 CE) and to [[Al-Farabi|al-F\u0101r\u0101b\u012b]] (c. 872\u2013950), and in the 28th book of [[Al-Zahrawi|al-Zahr\u0101w\u012b]]'s (Latin: Abulcasis, 936\u20131013) ''Kit\u0101b al-Ta\u1e63r\u012bf'' (later translated into Latin as ''Liber servatoris'').<ref>{{cite book|last1=al-Hassan|first1=Ahmad Y.|author-link=Ahmad Y. al-Hassan|year=2009|chapter=Alcohol and the Distillation of Wine in Arabic Sources from the 8th Century|title=Studies in al-Kimya': Critical Issues in Latin and Arabic Alchemy and Chemistry|location=Hildesheim|publisher=Georg Olms Verlag|pages=283\u2013298}} (same content also available on [http://www.history-science-technology.com/notes/notes7.html the author's website]); cf. {{cite book|last1=Berthelot|first1=Marcellin|author1-link=Marcellin Berthelot|last2=Houdas|first2=Octave V.|year=1893|title=La Chimie au Moyen \u00c2ge|volume=Vol. I\u2013III|location=Paris|publisher=Imprimerie nationale}} vol. I, pp. 141, 143.</ref> In the twelfth century, recipes for the production of ''aqua ardens'' ("burning water", i.e., ethanol) by distilling wine with salt started to appear in a number of Latin works, and by the end of the thirteenth century it had become a widely known substance among Western European chemists.<ref>{{cite book|last=Multhauf|first=Robert P.|author-link=Robert P. Multhauf|year=1966|title=The Origins of Chemistry|location=London|publisher=Oldbourne|isbn=9782881245947}} pp. 204\u2013206.</ref> The works of [[Taddeo Alderotti]] (1223\u20131296) describe a method for concentrating alcohol involving repeated distillation through a water-cooled still, by which an alcohol purity of 90% could be obtained.<ref>{{cite book|last1=Holmyard|first1=Eric John|author1-link=Eric John Holmyard|date=1957|title=Alchemy|location=Harmondsworth|publisher=Penguin Books|isbn=978-0-486-26298-7}} pp. 51\u201352.</ref>\n\nThe invention of [[steam distillation]] is attributed to the Persian physician [[Avicenna]].<ref>{{Cite book|last1=Fritz|first1=Sandy|url=https://books.google.com/books?id=BgjQDwAAQBAJ&dq=avicenna+steam+distillation+first+earliest&pg=PA21|title=Mosby's Fundamentals of Therapeutic Massage - E-Book|last2=Fritz|first2=Luke|date=2020-02-13|publisher=Elsevier Health Sciences|isbn=978-0-323-66184-3|language=en}}</ref><ref>{{Cite book|last=R\u00e4hse|first=Wilfried|url=https://books.google.com/books?id=VmFuAwAAQBAJ&dq=steam+distillation+avicenna&pg=PT445|title=Industrial Product Design of Solids and Liquids: A Practical Guide|date=2014-04-23|publisher=John Wiley & Sons|isbn=978-3-527-66761-1|language=en}}</ref><ref>{{Cite web|title=Distillation|url=https://www.chemeurope.com/en/encyclopedia/Distillation.html|access-date=2021-12-15|website=www.chemeurope.com|language=en}}</ref><ref>{{Cite book|last1=Oliveira|first1=Mozaniel Santana de|url=https://books.google.com/books?id=UJQtEAAAQBAJ&dq=steam+distillation+avicenna&pg=PA3|title=Essential Oils: Bioactive Compounds, New Perspectives and Applications|last2=Silva|first2=Sebasti\u00e3o|last3=Costa|first3=Wanessa Almeida Da|date=2020-09-09|publisher=BoD \u2013 Books on Demand|isbn=978-1-83962-697-5|language=en}}</ref>{{better source needed|date=December 2021}}\n\nThe [[fractional distillation]] of organic substances plays an important role in the works attributed to J\u0101bir ibn \u1e24ayy\u0101n, such as in the [[Seventy Books|{{transl|ar|Kit\u0101b al-Sab\u02bf\u012bn}}]] ('The Book of Seventy'), translated into Latin by [[Gerard of Cremona]] (c. 1114\u20131187) under the title {{lang|la|Liber de septuaginta}}.<ref>{{Cite book|last=Kraus|first=Paul|author-link=Paul Kraus (Arabist)|year=1942\u20131943|title=J\u00e2bir ibn Hayy\u00e2n: Contribution \u00e0 l'histoire des id\u00e9es scientifiques dans l'Islam. I. Le corpus des \u00e9crits j\u00e2biriens. II. J\u00e2bir et la science grecque|publisher=Institut Fran\u00e7ais d'Arch\u00e9ologie Orientale|location=Cairo|oclc=468740510|isbn=9783487091150}} Vol. II, p. 5. On the attribution of the Latin translation to Gerard of Cremona, see {{cite journal|last1=Burnett|first1=Charles|year=2001|title=The Coherence of the Arabic-Latin Translation Program in Toledo in the Twelfth Century|journal=Science in Context|volume=14|issue=1\u20132|pages=249\u2013288|doi=10.1017/S0269889701000096|s2cid=143006568}} p. 280; {{cite journal|last1=Moureau|first1=S\u00e9bastien|year=2020|title=Min al-k\u012bmiy\u0101\u02be ad alchimiam. The Transmission of Alchemy from the Arab-Muslim World to the Latin West in the Middle Ages|journal=Micrologus|volume=28|issue=|pages=87\u2013141|hdl=2078.1/211340|url=http://hdl.handle.net/2078.1/211340}} pp. 106, 111.</ref> The Jabirian experiments with fractional distillation of animal and vegetable substances, and to a lesser degree also of mineral substances, is the main topic of the {{lang|la|De anima in arte alkimiae}}, an originally Arabic work falsely attributed to [[Avicenna]] that was translated into Latin and would go on to form the most important alchemical source for [[Roger Bacon]] ({{circa|1220\u20131292}}).<ref>{{cite book|last1=Newman|first1=William R.|author1-link=William R. Newman|date=2000|chapter=Alchemy, Assaying, and Experiment|editor1-last=Holmes|editor1-first=Frederic L.|editor1-link=Frederic L. Holmes|editor2-last=Levere|editor2-first=Trevor H.|title=Instruments and Experimentation in the History of Chemistry|location=Cambridge|publisher=MIT Press|pages=35\u201354|isbn=9780262082822}} p. 44.</ref>\n\nA still was found in an archaeological site in Qinglong, [[Hebei]] province, in China, dating back to the 12th century. Distilled beverages were common during the [[Yuan dynasty]] (13th\u201314th centuries).<ref name="Haw"/>\n\nIn 1500, German alchemist [[Hieronymus Braunschweig]] published ''Liber de arte destillandi'' (''The Book of the Art of Distillation''),<ref>{{cite book |first=Hieronymus |last=Braunschweig |author-link=Hieronymus Braunschweig |date=1500 |title=Liber de arte destillandi, de Simplicibus |trans-title=The Book of the Art of Distillation |language=de |url=https://bildsuche.digitale-sammlungen.de/index.html?c=viewer&bandnummer=bsb00031146&pimage=7&v=2p&nav=&l=de}}</ref> the first book solely dedicated to the subject of distillation, followed in 1512 by a much expanded version. In 1651, [[John French (doctor)|John French]] published ''The Art of Distillation'',<ref>{{cite book |first=John |last=French |author-link=John French (doctor) |date=1651 |title=The Art of Distillation |publisher=Richard Cotes |location=London |url=http://www.levity.com/alchemy/jfren_ar.html}}</ref> the first major English compendium on the practice, but it has been claimed<ref>{{cite journal|doi=10.1021/ie50318a015|year=1936|title=Distillation|journal=Industrial & Engineering Chemistry|volume=28|issue=6|pages=677}}</ref> that much of it derives from Braunschweig's work. This includes diagrams with people in them showing the industrial rather than bench scale of the operation.\n[[File:Hieronymus Brunschwig Liber de arte Distillandi CHF AQ13x3.jpg|thumb|Hieronymus Brunschwig's ''Liber de arte Distillandi de Compositis'' (Strassburg, 1512) [https://www.sciencehistory.org/distillations/podcast/the-alchemical-quest Science History Institute]]]\n[[File:My retort.jpg|thumb|A [[retort]]]]\n[[File:Distillation by Retort.png|thumb|Distillation]]\n[[File:UkrainianVodkaStill.jpg|thumb|Old Ukrainian vodka still]]\n[[File:Dorf Lore - Schnaps-Destillation.jpg|thumb|Simple liqueur distillation in [[East Timor]]]]\n\nAs [[alchemy]] evolved into the science of [[chemistry]], vessels called [[retort]]s became used for distillations. Both [[alembic]]s and retorts are forms of [[Laboratory glassware|glassware]] with long necks pointing to the side at a downward angle to act as air-cooled [[Condenser (heat transfer)|condensers]] to [[Condensation|condense]] the distillate and let it drip downward for collection. Later, copper alembics were invented. Riveted joints were often kept tight by using various mixtures, for instance a dough made of rye flour.<ref>[https://web.archive.org/web/20121104173651/http://www.copper-alembic.com/manufacturing/specs_sealing.php Sealing Technique], accessed 16 November 2006.</ref> These alembics often featured a cooling system around the beak, using cold water, for instance, which made the condensation of alcohol more efficient. These were called [[pot still]]s. Today, the retorts and pot stills have been largely supplanted by more efficient distillation methods in most industrial processes. However, the pot still is still widely used for the elaboration of some fine alcohols, such as [[cognac (drink)|cognac]], [[Scotch whisky]], [[Irish whiskey]], [[tequila]], [[rum]], and some [[vodka]]s. Pot stills made of various materials (wood, clay, stainless steel) are also used by [[Rum-runner|bootleggers]] in various countries. Small pot stills are also sold for use in the domestic production<ref>[http://www.essentialoil.com/alembic5.html Traditional Alembic Pot Still] {{webarchive|url=https://web.archive.org/web/20061121163501/https://www.essentialoil.com/alembic5.html |date=21 November 2006 }}, accessed 16 November 2006.</ref> of flower water or [[essential oils]].\n\nEarly forms of distillation involved batch processes using one vaporization and one condensation. Purity was improved by further distillation of the condensate. Greater volumes were processed by simply repeating the distillation. Chemists reportedly carried out as many as 500 to 600 distillations in order to obtain a pure compound.<ref name=Othmer>Othmer, D. F. (1982) "Distillation \u2013 Some Steps in its Development", in W. F. Furter (ed) ''A Century of Chemical Engineering''. {{ISBN|0-306-40895-3}}</ref>\n\nIn the early 19th century, the basics of modern techniques, including pre-heating and [[reflux]], were developed.<ref name=Othmer/> In 1822, Anthony Perrier developed one of the first continuous stills, and then, in 1826, Robert Stein improved that design to make his [[column still|patent still]]. In 1830, [[Aeneas Coffey]] got a patent for improving the design even further.<ref>{{cite patent |inventor-first=A. |inventor-last=Coffey |inventor-link=Aeneas Coffey |title=Apparatus for Brewing and Distilling |country-code=GB |patent-number=5974 |publication-date=5 August 1830 |issue-date=5 February 1831}}; [http://www.kennetpans.info/index.php?option=com_content&view=article&id=231&Itemid=405 image] {{webarchive|url=https://web.archive.org/web/20170204221819/http://kennetpans.info/index.php?option=com_content&view=article&id=231&Itemid=405 |date=4 February 2017 }}</ref> Coffey's continuous still may be regarded as the [[archetype]] of modern petrochemical units. The French engineer Armand Savalle developed his steam regulator around 1846.<ref name="Forbes" />{{rp|p=323}} In 1877, [[Ernest Solvay]] was granted a U.S. Patent for a tray column for [[ammonia]] distillation,<ref>{{cite patent |inventor-first=Ernest |inventor-last=Solvay |inventor-link=Ernest Solvay |country-code=US |patent-number=198699 |title=Improvement in the Ammonia-Soda Manufacture |publication-date=2 June 1876 |issue-date=25 December 1877}}</ref> and the same and subsequent years saw developments in this theme for oils and spirits.\n\nWith the emergence of [[chemical engineering]] as a discipline at the end of the 19th century, scientific rather than empirical methods could be applied. The developing [[petroleum]] industry in the early 20th century provided the impetus for the development of accurate design methods, such as the [[McCabe\u2013Thiele method]] by [[Ernest Thiele]] and the [[Fenske equation]]. The first industrial plant in the United States to use distillation as a means of ocean desalination opened in [[Freeport, Texas]] in 1961 with the hope of bringing [[water security]] to the region.<ref name="Transcript">{{cite web |title=Making the Deserts Bloom: Harnessing nature to deliver us from drought, Distillations Podcast and transcript, Episode 239 |url=https://www.sciencehistory.org/distillations/podcast/making-the-deserts-bloom |website=Science History Institute|date=March 19, 2019 |access-date=27 August 2019}}</ref>\nThe availability of powerful computers has allowed direct [[computer simulation]]s of distillation columns."}},
{"article_title": "DNA ligase", "pageid": "8697", "revid": "1060773552", "timestamp": "2021-12-17T15:50:02Z", "history_paths": [["DNA ligase --- Introduction ---", "History"]], "categories": ["ec 6.5", "biotechnology", "dna replication", "enzymes", "genetics techniques", "molecular biology"], "heading_tree": {"DNA ligase --- Introduction ---": {"Enzymatic mechanism": {}, "Types": {"''E. coli''": {}, "T4": {}, "Mammalian": {}, "Thermostable": {}}, "Measurement of activity": {}, "Research applications": {}, "History": {}, "Disorders": {"Xeroderma pigmentosum": {}, "Ataxia-telangiectasia": {}, "Fanconi Anemia": {}, "Bloom syndrome": {}}, "As a drug target": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"DNA ligase --- Introduction ---|History": "The first DNA ligase was purified and characterized in 1967 by the Gellert, Lehman, Richardson, and Hurwitz laboratories.<ref name="Shuman 17365\u201317369">{{cite journal | vauthors = Shuman S | title = DNA ligases: progress and prospects | journal = The Journal of Biological Chemistry | volume = 284 | issue = 26 | pages = 17365\u20139 | date = June 2009 | pmid = 19329793 | pmc = 2719376 | doi = 10.1074/jbc.R900017200 | doi-access = free }}</ref> It was first purified and characterized by Weiss and Richardson using a six-step chromatographic-fractionation process beginning with elimination of cell debris and addition of streptomycin, followed by several Diethylaminoethyl (DEAE)-cellulose column washes and a final phosphocellulose fractionation. The final extract contained 10% of the activity initially recorded in the ''E. coli ''media; along the process it was discovered that ATP and Mg++ were necessary to optimize the reaction. The common commercially available DNA ligases were originally discovered in [[Enterobacteria phage T4|bacteriophage T4]], ''[[Escherichia coli|E. coli]]'' and other [[bacteria]].<ref name="WeissRichardson1967">{{cite journal | vauthors = Weiss B, Richardson CC | title = Enzymatic breakage and joining of deoxyribonucleic acid, I. Repair of single-strand breaks in DNA by an enzyme system from Escherichia coli infected with T4 bacteriophage | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 57 | issue = 4 | pages = 1021\u20138 | date = April 1967 | pmid = 5340583 | pmc = 224649 | doi = 10.1073/pnas.57.4.1021 | bibcode = 1967PNAS...57.1021W | doi-access = free }}</ref>"}},
{"article_title": "Digital video", "pageid": "8733", "revid": "1062451144", "timestamp": "2021-12-28T15:01:06Z", "history_paths": [["Digital video --- Introduction ---", "History"]], "categories": ["film and video technology", "video signal", "television terminology", "audiovisual introductions in 1986", "film and video terminology"], "heading_tree": {"Digital video --- Introduction ---": {"History": {"Digital video cameras": {}, "Digital video coding": {}, "Digital video production": {}, "Digital Video and Culture": {}, "Digital Television": {}}, "Overview": {"Interlacing": {}, "Bit rate and BPP": {"Constant bit rate versus variable bit rate": {}}}, "Technical overview": {}, "Technical Properties": {}, "Interfaces and cables": {}, "Storage formats": {"Encoding": {}, "Tapes": {}, "Discs": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Digital video --- Introduction ---|History": "{{See|Digital cinematography|Image sensor|Video camera}}\n\nThe basis for [[digital video camera]]s are [[metal-oxide-semiconductor]] (MOS) [[image sensors]].<ref name="Williams">{{cite book |last1=Williams |first1=J. B. |title=The Electronics Revolution: Inventing the Future |date=2017 |publisher=Springer |isbn=9783319490885 |pages=245\u20138 |url=https://books.google.com/books?id=v4QlDwAAQBAJ&pg=PA245}}</ref> The first practical [[semiconductor]] image sensor was the [[charge-coupled device]] (CCD), invented in 1969<ref>{{Cite book | title = Scientific charge-coupled devices | author = James R. Janesick | publisher = SPIE Press | year = 2001 | isbn = 978-0-8194-3698-6 | pages = 3\u20134 | url = https://books.google.com/books?id=3GyE4SWytn4C&pg=PA3 }}</ref> by Willard S. Boyle, who won a Nobel Prize for his work in physics.<ref>{{Cite journal|date=2009|title=2009 Nobel Prize in Physics awarded to Kao, Boyle, and Smith|url=http://dx.doi.org/10.1063/pt.5.023739|journal=Physics Today|doi=10.1063/pt.5.023739|issn=1945-0699}}</ref> based on [[MOS capacitor]] technology.<ref name="Williams"/> Following the commercialization of CCD sensors during the late 1970s to early 1980s, the [[entertainment industry]] slowly began transitioning to [[digital imaging]] and digital video over from analog video the next two decades.<ref>{{cite book |last1=Stump |first1=David |title=Digital Cinematography: Fundamentals, Tools, Techniques, and Workflows |date=2014 |publisher=[[CRC Press]] |isbn=978-1-136-04042-9 |pages=83\u20135 |url=https://books.google.com/books?id=c-MjAwAAQBAJ&pg=PA83}}</ref> The CCD was followed by the [[CMOS]] [[active-pixel sensor]] ([[CMOS sensor]]),<ref>{{cite book |last1=Stump |first1=David |title=Digital Cinematography: Fundamentals, Tools, Techniques, and Workflows |date=2014 |publisher=[[CRC Press]] |isbn=978-1-136-04042-9 |pages=19\u201322 |url=https://books.google.com/books?id=c-MjAwAAQBAJ&pg=PA19}}</ref> developed in the 1990s.<ref name="Fossum2014">{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |last2=Hondongwa |first2=D. B. |title=A Review of the Pinned Photodiode for CCD and CMOS Image Sensors |journal=IEEE Journal of the Electron Devices Society |date=2014 |volume=2 |issue=3 |pages=33\u201343 |doi=10.1109/JEDS.2014.2306412 |doi-access=free }}</ref><ref name=fossum93>{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |title=Active pixel sensors: are CCDs dinosaurs? |journal=SPIE Proceedings Vol. 1900: Charge-Coupled Devices and Solid State Optical Sensors III |volume=1900 |date=12 July 1993 |doi=10.1117/12.148585 |bibcode=1993SPIE.1900....2F |citeseerx=10.1.1.408.6558 |publisher=International Society for Optics and Photonics |pages=2\u201314 |s2cid=10556755 |editor1-last=Blouke |editor1-first=Morley M.}}</ref> CMOS are beneficial because of their small size, high speed, and low power usage. CMOS are most commonly found today in the digital cameras in iPhones, used as the image censor for the device.<ref>{{Cite web|title=The Heart of a Phone Camera: The CMOS Active Pixel Image Sensor|url=http://large.stanford.edu/courses/2012/ph250/lu2/|access-date=2021-03-26|website=large.stanford.edu}}</ref>\n[[File:Betacam_SP_camera.jpg|thumb|A Betacam SP camera, originally developed in 1986 by Sony.]]\n\n {{See|Video coding format#History}}\n\nThe earliest forms of digital [[video coding]] began in the 1970s, with uncompressed [[pulse-code modulation]] (PCM) video, requiring high [[bitrate]]s between 45{{ndash}}140 [[Mbps]] for [[standard definition]] (SD) content By the 1980s, the [[discrete cosine transform]] (DCT) became the standard for digital [[video compression]].\n\nThe first digital [[video coding standard]] was [[H.120]], created by the (International Telegraph and Telephone Consultative Committee) or [[ITU-T|CCITT]] (now ITU-T) in 1984. H.120 was not practical due to weak performance.<ref name="history">{{cite web |title=The History of Video File Formats Infographic |url=http://www.real.com/resources/digital-video-file-formats/ |website=[[RealNetworks]] |access-date=5 August 2019 |date=22 April 2012}}</ref> H.120 was based on [[differential pulse-code modulation]] (DPCM), a compression algorithm that was inefficient for video coding. During the late 1980s, a number of companies began experimenting with DCT, a much more efficient form of compression for video coding. The CCITT received 14 proposals for DCT-based video compression formats, in contrast to a single proposal based on [[vector quantization]] (VQ) compression. The [[H.261]] standard was developed based on DCT compression,<ref name="Ghanbari">{{cite book|last1=Ghanbari|first1=Mohammed|url=https://books.google.com/books?id=7XuU8T3ooOAC&pg=PA1|title=Standard Codecs: Image Compression to Advanced Video Coding|date=2003|publisher=[[Institution of Engineering and Technology]]|isbn=9780852967102|pages=1\u20132}}</ref> becoming first practical video coding standard.<ref name="history" /> Since H.261, DCT compression has been adopted by all the major video coding standards that followed.<ref name="Ghanbari"/>\n\n[[MPEG-1]], developed by the [[Motion Picture Experts Group]] (MPEG), followed in 1991, and it was designed to compress [[VHS]]-quality video. It was succeeded in 1994 by [[MPEG-2]]/[[H.262/MPEG-2 Part 2|H.262]],<ref name="history"/> which became the standard video format for [[DVD]] and [[Standard definition|SD]] [[digital television]].<ref name="history"/> It was followed by [[MPEG-4 Visual|MPEG-4]]/[[H.263]] in 1999, and then in 2003 it was followed by [[H.264/MPEG-4 AVC]], which has become the most widely used video coding standard.<ref name="history"/>\n\n Starting in the late 1970s to the early 1980s, [[video production]] equipment that was digital in its internal workings was introduced. These included [[time base corrector]]s (TBC){{efn|For example the [[Thomson-CSF]] 9100 Digital Video Processor, an internally all-digital full-frame TBC introduced in 1980.}} and [[digital video effects]] (DVE) units.{{efn|For example the [[Ampex]] ADO, and the [[Nippon Electric Corporation]] (NEC) DVE.}} They operated by taking a standard analog [[composite video]] input and digitizing it internally. This made it easier to either correct or enhance the video signal, as in the case of a TBC, or to manipulate and add effects to the video, in the case of a DVE unit. The digitized and processed video information was then converted back to standard analog video for output.\n\nLater on in the 1970s, manufacturers of professional video broadcast equipment, such as [[Robert Bosch GmbH|Bosch]] (through their [[Fernseh]] division) and [[Ampex]] developed prototype digital [[videotape recorder]]s (VTR) in their research and development labs. Bosch's machine used a modified [[1 inch type B videotape]] transport and recorded an early form of [[CCIR 601]] digital video. Ampex's prototype digital video recorder used a modified [[2-inch quadruplex videotape]] VTR (an Ampex AVR-3) fitted with custom digital video electronics and a special "octaplex" 8-head headwheel (regular analog 2" quad machines only used 4 heads). Like standard 2" quad, the audio on the Ampex prototype digital machine, nicknamed by its developers as "Annie," still recorded the audio in analog as linear tracks on the tape. None of these machines from these manufacturers were ever marketed commercially.\n\nDigital video was first introduced commercially in 1986 with the Sony [[D-1 (Sony)|D1]] format, which recorded an uncompressed [[standard definition]] [[component video]] signal in digital form. Component video connections required 3 cables, but most [[television]] facilities were wired for composite NTSC or PAL video using one cable. Due this incompatibility the cost of the recorder, D1 was used primarily by large [[television network]]s and other component-video capable video studios.\n[[File:A_todo_o_nada_Chile_Studio_(20200130_194157).jpg|thumb|A professional television studio set in Chile.]]\nIn 1988, Sony and Ampex co-developed and released the [[D-2 (video)|D2]] digital videocassette format, which recorded video digitally without compression in [[ITU-601]] format, much like D1. In comparison, D2 had the major difference of encoding the video in composite form to the NTSC standard, thereby only requiring single-cable composite video connections to and from a D2 VCR. This made it a perfect fit for the majority of television facilities at the time. D2 was a successful format in the [[television broadcast]] industry throughout the late '80s and the '90s. D2 was also widely used in that era as the master tape format for mastering [[laserdiscs]].{{efn|Prior to D2, most laserdiscs were mastered using analog [[1" Type C videotape]]}}\n\nD1 & D2 would eventually be replaced by cheaper systems using [[video compression]], most notably Sony's [[Digital Betacam]],{{efn|Digital Betacam is still heavily used as an [[electronic field production]] (EFP) recording format by professional television producers}} that were introduced into the network's [[television studio]]s. Other examples of digital video formats utilizing compression were Ampex's [[DCT (videocassette format)|DCT]] (the first to employ such when introduced in 1992), the industry-standard [[DV]] and MiniDV and its professional variations, Sony's [[DVCAM]] and Panasonic's [[DVCPRO]], and [[Betacam SX]], a lower-cost variant of Digital Betacam using [[MPEG-2]] compression.<ref>{{Cite book|last=Roger|first=Jennings|title=Special Edition Using Desktop Video|publisher=Que Books, Macmillan Computer Publishing|year=1997|isbn=978-0789702654}}</ref>\n[[File:Sony_logo.svg|thumb|The Sony logo, creator of the Betacam.]]\nOne of the first digital video products to run on personal computers was ''PACo: The PICS Animation Compiler'' from The Company of Science & Art in Providence, RI. It was developed starting in 1990 and first shipped in May 1991. PACo could stream unlimited-length video with synchronized sound from a single file (with the ".CAV" [[file extension]]) on CD-ROM. Creation required a Mac, and playback was possible on Macs, PCs, and Sun [[SPARCstation]]s.<ref>{{cite web |title=CoSA Lives: The Story of the Company Behind After Effects |url=http://www.motionworks.com.au/2009/11/cosa-lives/ |archive-url=https://web.archive.org/web/20110227132422/http://motionworks.com.au/2009/11/cosa-lives/ |archive-date=2011-02-27 |access-date=2009-11-16 |url-status=live }}</ref>\n\n[[QuickTime]], [[Apple Computer]]'s multimedia framework, was released in June 1991. [[Audio Video Interleave]] from [[Microsoft]] followed in 1992. Initial consumer-level content creation tools were crude, requiring an analog video source to be digitized to a computer-readable format. While low-quality at first, consumer digital video increased rapidly in quality, first with the introduction of playback standards such as [[MPEG-1]] and [[MPEG-2]] (adopted for use in television transmission and [[DVD]] media), and the introduction of the [[DV]] tape format allowing recordings in the format to be transferred directly to digital video files using a [[FireWire]] port on an editing computer. This simplified the process, allowing [[non-linear editing system]]s (NLE) to be deployed cheaply and widely on [[desktop computer]]s with no external playback or recording equipment needed.\n\nThe widespread adoption of digital video and accompanying compression formats has reduced the bandwidth needed for a [[high-definition video]] signal (with [[HDV]] and [[AVCHD]], as well as several commercial variants such as [[DVCPRO]]-HD, all using less bandwidth than a standard definition analog signal). These savings have increased the number of channels available on [[cable television]] and [[direct broadcast satellite]] systems, created opportunities for [[spectrum reallocation]] of [[terrestrial television]] broadcast frequencies, and made [[tapeless camcorder]]s based on [[flash memory]] possible, among other innovations and efficiencies.\n\n Culturally, digital video has allowed video and film to become widely available and popular, beneficial to entertainment, education, and research.<ref name=":1">{{Cite journal|last=Garrett|first=Bradley L.|date=2018|title=Videographic geographies: Using digital video for geographic research|url=http://journals.sagepub.com/doi/10.1177/0309132510388337|journal=Progress in Human Geography|language=en|volume=35|issue=4|pages=521\u2013541|doi=10.1177/0309132510388337|s2cid=131426433|issn=0309-1325}}</ref> Digital video is increasingly common in schools, with students and teachers taking an interest in learning how to use it in relevant ways.<ref>{{Cite journal|last1=Bruce|first1=David L.|last2=Chiu|first2=Ming Ming|date=2015|title=Composing With New Technology: Teacher Reflections on Learning Digital Video|url=http://journals.sagepub.com/doi/10.1177/0022487115574291|journal=Journal of Teacher Education|language=en|volume=66|issue=3|pages=272\u2013287|doi=10.1177/0022487115574291|s2cid=145361658|issn=0022-4871}}</ref> Digital video also has healthcare applications, allowing doctors to track infant heart rates and oxygen levels.<ref>{{Cite journal|last1=Wieler|first1=Matthew E.|last2=Murphy|first2=Thomas G.|last3=Blecherman|first3=Mira|last4=Mehta|first4=Hiral|last5=Bender|first5=G. Jesse|date=2021-03-01|title=Infant heart-rate measurement and oxygen desaturation detection with a digital video camera using imaging photoplethysmography|url=http://dx.doi.org/10.1038/s41372-021-00967-1|journal=Journal of Perinatology|volume=41|issue=7|pages=1725\u20131731|doi=10.1038/s41372-021-00967-1|pmid=33649437|s2cid=232070728|issn=0743-8346}}</ref>\n\nIn addition, the switch from analog to digital video impacted media in various ways, such as in how business use cameras for surveillance. [[Closed-circuit television|Closed circuit television]] (CCTV) switched to using [[digital video recorder]]s (DVR), presenting the issue of how to store recordings for evidence collection. Today, digital video is able to be [[Compressed video|compressed]] in order to save storage space.<ref>{{Cite journal|last1=Bruehs|first1=Walter E.|last2=Stout|first2=Dorothy|date=2020|title=Quantifying and Ranking Quality for Acquired Recordings on Digital Video Recorders|url=https://onlinelibrary.wiley.com/doi/10.1111/1556-4029.14307|journal=Journal of Forensic Sciences|language=en|volume=65|issue=4|pages=1155\u20131168|doi=10.1111/1556-4029.14307|pmid=32134510|s2cid=212417006|issn=0022-1198}}</ref>\n\n [[Digital television|Digital Television]], also known as DTV, is the production and transmission of digital video from networks to consumers. This technique uses digital encoding instead of analog signals used prior to the 1950s.<ref>{{Cite book|last=Kruger|first=Lennard G.|url=https://www.worldcat.org/oclc/50684535|title=Digital television : an overview|date=2002|publisher=Novinka Books|others=Peter F. Guerrero|isbn=1-59033-502-3|location=New York|oclc=50684535}}</ref> As compared to analog methods, DTV is faster and provides more capabilities and options for data to be transmitted and shared.<ref>{{Cite journal|last=Reimers|first=U.|date=1998|title=Digital video broadcasting|url=https://ieeexplore.ieee.org/document/685371|journal=IEEE Communications Magazine|volume=36|issue=6|pages=104\u2013110|doi=10.1109/35.685371}}</ref>"}},
{"article_title": "Digital cinema", "pageid": "8844", "revid": "1059823756", "timestamp": "2021-12-11T21:18:20Z", "history_paths": [["Digital cinema --- Introduction ---", "History"]], "categories": ["film and video technology", "digital media", "cinematography", "filmmaking"], "heading_tree": {"Digital cinema --- Introduction ---": {"History": {"Foundations": {}, "Initiatives": {}, "Worldwide deployment": {}}, "Elements": {}, "Technology and standards": {"Digital Cinema Initiatives": {}, "National Association of Theatre Owners": {}, "E-Cinema": {}}, "Projectors for digital cinema": {"DLP Cinema": {}, "Sony SXRD": {}, "Stereo 3D images": {}, "Laser": {}}, "LED screen for digital cinema": {}, "Effect on distribution": {"Telecommunication": {}, "Live broadcasting to cinemas": {}}, "Pros and cons": {"Pros": {}, "Cons": {}, "Costs": {"Pros": {}, "Cons": {}}}, "See also": {}, "References": {}, "Bibliography": {}, "Filmography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Digital cinema --- Introduction ---|History": "The transition from film to [[digital video]] was preceded by cinema's transition from analog to [[digital audio]], with the release of the [[Dolby Digital]] (AC-3) [[audio coding standard]] in 1991.<ref name="Britanak">{{cite journal |last1=Britanak |first1=V. |title=On Properties, Relations, and Simplified Implementation of Filter Banks in the Dolby Digital (Plus) AC-3 Audio Coding Standards |journal=IEEE Transactions on Audio, Speech, and Language Processing |date=2011 |volume=19 |issue=5 |pages=1231\u20131241 |doi=10.1109/TASL.2010.2087755|s2cid=897622 }}</ref> Its main basis is the [[modified discrete cosine transform]] (MDCT), a [[lossy compression|lossy]] [[audio compression (data)|audio compression]] algorithm.<ref>{{cite journal |last1=Andersen |first1=Robert Loring |last2=Crockett |first2=Brett Graham |last3=Davidson |first3=Grant A. |last4=Davis |first4=Mark Franklin |last5=Fielder |first5=Louis D. |last6=Turner |first6=Stephen C. |last7=Vinton |first7=Mark S. |last8=Williams |first8=Phillip |title=Introduction to Dolby Digital Plus, an Enhancement to the Dolby Digital Coding System |journal=[[Audio Engineering Society|Audio Engineering Society Convention]] |date=October 2004 |issue=117th AES Convention |pages=1\u201329 |url=https://www.dolby.com/in/en/technologies/aes-convention-paper-intro-to-dolby-digital-plus.pdf |access-date=17 October 2019}}</ref> It is a modification of the [[discrete cosine transform]] (DCT) algorithm, which was first proposed by [[N. Ahmed|Nasir Ahmed]] in 1972 and was originally intended for [[image compression]].<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I Came Up With the Discrete Cosine Transform |journal=[[Digital Signal Processing (journal)|Digital Signal Processing]] |date=January 1991 |volume=1 |issue=1 |pages=4\u20135 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform}}</ref> The DCT was adapted into the MDCT by J.P. Princen, A.W. Johnson and Alan B. Bradley at the [[University of Surrey]] in 1987,<ref>{{cite journal |last1=Princen |first1=J.P. |last2=Johnson |first2=A.W. |last3=Bradley |first3=Alan B. |title=Subband/Transform coding using filter bank designs based on time domain aliasing cancellation |journal=ICASSP '87. IEEE International Conference on Acoustics, Speech, and Signal Processing |date=1987 |volume=12 |pages=2161\u20132164 |doi=10.1109/ICASSP.1987.1169405|s2cid=58446992 }}</ref> and then [[Dolby Laboratories]] adapted the MDCT algorithm along with [[perceptual coding]] principles to develop the AC-3 audio format for cinema needs.<ref name="Britanak"/> [[1990s in film|Cinema in the 1990s]] typically combined analog video with digital audio.\n\nDigital media playback of high-resolution 2K files has at least a 20-year history. Early video data storage units ([[RAID]]s) fed custom frame buffer systems with large memories.  In early digital video units, content was usually restricted to several minutes of material. Transfer of content between remote locations was slow and had limited capacity. It was not until the late 1990s that feature-length films could be sent over the "wire" (Internet or dedicated fiber links). On October 23, 1998, [[Digital Light Processing]] (DLP) projector technology was publicly demonstrated with the release of ''[[The Last Broadcast (film)|The Last Broadcast]]'', the first feature-length movie, shot, edited and distributed digitally.<ref>{{cite web|url=http://www.upenn.edu/pennnews/current/1998-10-15/editors-pick/live-satellite-first-digital-premiere |title=Live via satellite: the first digital premiere | Penn Current |publisher=Upenn.edu |date=1998-10-15}}</ref><ref>{{cite news|url=http://www.indiewire.com/article/d_day_for_two_digital_movies_as_the_cruise_and_the_last_broadcast_debut_in_ |title=D Day for Two Digital Movies as "The Cruise" and "The Last Broadcast" Debut in Theaters Today | Filmmakers, Film Industry, Film Festivals, Awards & Movie Reviews |work=Indiewire }}</ref><ref>{{cite web|url=http://www.thelastbroadcastmovie.com/tlb99/filmmakersbios.htm |title=The Last Broadcast |publisher=Thelastbroadcastmovie.com }}</ref> In conjunction with Texas Instruments, the movie was publicly demonstrated in five theaters across the United States ([[Philadelphia]], [[Portland, Oregon|Portland (Oregon)]], [[Minneapolis]], [[Providence, Rhode Island|Providence]], and [[Orlando, Florida|Orlando]]).\n\n [[File:Texas Instruments, DLP Cinema Prototype System, Mark V, Paris, 2000 - Philippe Binant Archives.jpg|thumb|Texas Instruments, DLP Cinema Prototype Projector, Mark V, 2000]]\nIn the United States, on June 18, 1999, Texas Instruments' ''DLP Cinema'' projector technology was publicly demonstrated on two screens in Los Angeles and New York for the release of Lucasfilm's ''[[Star Wars: Episode I \u2013 The Phantom Menace|Star Wars Episode I: The Phantom Menace]]''.<ref>[[Charles S. Swartz]] (editor), ''Understanding digital cinema'', 2005, p. 159.</ref> In Europe, on February 2, 2000, Texas Instruments' ''DLP Cinema'' projector technology was publicly demonstrated, by Philippe Binant, on one screen in Paris for the release of ''[[Toy Story 2]]''.<ref>[[Jean-Michel Frodon]] and [[Dina Iordanova]] (editors), ''Cinemas of Paris'', University of St Andrews, Scotland, 2016, p. 149.</ref><ref>{{Cite web|url=http://www.silverscreens.com/ts2digit.php|title=Silver Screens - Toy Story en num\u00e9rique \u00e0 Paris|website=www.silverscreens.com}}</ref>\n\nFrom 1997 to 2000, the [[JPEG 2000]] [[image compression]] standard was developed by a [[Joint Photographic Experts Group]] (JPEG) committee chaired by Touradj Ebrahimi (later the JPEG president).<ref>{{cite book |last1=Taubman |first1=David |last2=Marcellin |first2=Michael |title=JPEG2000 Image Compression Fundamentals, Standards and Practice: Image Compression Fundamentals, Standards and Practice |date=2012 |publisher=[[Springer Science & Business Media]] |isbn=9781461507994 |url=https://books.google.com/books?id=y7HeBwAAQBAJ&pg=PA402}}</ref> In contrast to the original 1992 [[JPEG]] standard, which is a DCT-based [[lossy compression]] format for static [[digital images]], JPEG 2000 is a [[discrete wavelet transform]] (DWT) based compression standard that could be adapted for motion imaging [[video compression]] with the [[Motion JPEG 2000]] extension. JPEG 2000 technology was later selected as the [[video coding standard]] for digital cinema in 2004.<ref name="Swartz">{{cite book |last1=Swartz |first1=Charles S. |title=Understanding Digital Cinema: A Professional Handbook |date=2005 |publisher=[[Taylor & Francis]] |isbn=9780240806174 |page=147 |url=https://books.google.com/books?id=tYw3ehoBnjkC&pg=PA147}}</ref>\n\n On January 19, 2000, the [[Society of Motion Picture and Television Engineers]], in the United States, initiated the first standards group dedicated towards developing digital cinema.<ref>{{cite news |url=http://www.mkpe.com/publications/d-cinema/misc/dc28_takes_off.php |title=SMPTE's Digital Cinema Committee Takes Off Running |publisher=MKPE consulting |year=2000 |access-date=2011-10-25}}</ref> By December 2000, there were 15 digital cinema screens in the United States and Canada, 11 in Western Europe, 4 in Asia, and 1 in South America.<ref>{{cite journal|url=http://www.europa-distribution.org/files/bruxelles/digital_cinema_figures.pdf |title=DIGITAL CINEMA \u2013 KEY FIGURES & FACTS |date=2006-07-23}}</ref> [[Digital Cinema Initiatives]] (DCI) was formed in March 2002 as a joint project of many motion picture studios ([[Walt Disney Studios (division)|Disney]], [[20th Century Fox|Fox]], [[MGM]], [[Paramount Pictures|Paramount]], [[Sony Pictures Entertainment|Sony Pictures]], [[Universal Studios|Universal]] and [[Warner Bros. Studios|Warner Bros.]]) to develop a system specification for digital cinema.<ref>{{cite web|url=http://www.dcimovies.com/ |title=Digital Cinema Initiatives (DCI) - DIGITAL CINEMA SYSTEM SPECIFICATION, VERSION 1.2 |publisher=Dcimovies.com }}</ref>\n\nIn April 2004, in cooperation with the [[American Society of Cinematographers]], DCI created standard evaluation material (the ASC/DCI StEM material) for testing of 2K and 4K playback and compression technologies. DCI selected [[JPEG 2000]] as the basis for the compression in the system the same year.<ref>{{Cite web | url=https://www.imdb.com/title/tt1666288/trivia |title = ASC-DCI StEM (2004)|website = [[IMDb]]}}</ref> Initial tests with JPEG 2000 produced [[bit rate]]s of around 75{{ndash}}125 [[Mbit/s]] for [[2K resolution]] and 100{{ndash}}200 Mbit/s for [[4K resolution]].<ref name="Swartz"/>\n\n In China, in June 2005, an e-cinema system called "dMs" was established and was used in over 15,000 screens spread across China's 30 provinces. dMs estimated that the system would expand to 40,000 screens in 2009.<ref>[http://www.dmcc.gov.cn China Digital Cinema Development Center]</ref> In 2005 the UK Film Council Digital Screen Network launched in the UK by Arts Alliance Media creating a chain of 250 2K digital cinema systems. The roll-out was completed in 2006. This was the first mass roll-out in Europe. AccessIT/Christie Digital also started a roll-out in the United States and Canada. By mid 2006, about 400 theaters were equipped with 2K digital projectors with the number increasing every month. In August 2006, the [[Malayalam]] digital movie ''[[Moonnamathoral]]'', produced by Benzy Martin, was distributed via satellite to cinemas, thus becoming the first Indian digital cinema. This was done by Emil and Eric Digital Films, a company based at Thrissur using the end-to-end digital cinema system developed by Singapore-based DG2L Technologies.<ref name="The Hindu">{{cite news | url=http://www.hindu.com/2006/08/19/stories/2006081901860200.htm | archive-url=https://web.archive.org/web/20061210045041/http://www.hindu.com/2006/08/19/stories/2006081901860200.htm | url-status=dead | archive-date=2006-12-10 | title= Digital movie in Malayalam released | date=2006-08-19 | newspaper=[[The Hindu]] | access-date=2006-08-23 }}</ref>\n\nIn January 2007, ''[[Guru (2007 film)|Guru]]'' became the first [[Indian film]] mastered in the DCI-compliant JPEG 2000 Interop format and also the first Indian film to be previewed digitally, internationally, at the Elgin Winter Garden in Toronto. This film was digitally mastered at Real Image Media Technologies in India. In 2007, the UK became home to Europe's first DCI-compliant fully digital multiplex cinemas; Odeon Hatfield and Odeon Surrey Quays (in London), with a total of 18 digital screens, were launched on 9 February 2007. By March 2007, with the release of Disney's ''[[Meet the Robinsons]]'', about 600 screens had been equipped with digital projectors. In June 2007, Arts Alliance Media announced the first European commercial digital cinema [[Virtual Print Fee]] (VPF) agreements (with [[20th Century Fox]] and [[Universal Pictures]]). In March 2009 [[AMC Theatres]] announced that it closed a $315 million deal with [[Sony]] to replace all of its [[movie projector]]s with 4K digital projectors starting in the second quarter of 2009; it was anticipated that this replacement would be finished by 2012.<ref>{{Cite news   | last = Taub  | first = Eric A.  | title = AMC to Get Sony Digital Projectors  | newspaper = New York Times  | location = New York  | date = March 29, 2009  | url = https://www.nytimes.com/2009/03/30/technology/companies/30sony.html  | access-date = November 19, 2009}}</ref>\n[[Image:Ten Main Center-AMC Bldg-Kansas City MO.jpg|thumb|[[AMC Theatres]] former corporate headquarters in Kansas City, prior to their 2013 move to Leawood, Kansas.]]\n\nIn January 2011, the total number of digital screens worldwide was 36,242, up from 16,339 at end 2009 or a growth rate of 121.8 percent during the year.<ref>{{cite web | url=http://www.isuppli.com/media-research/marketwatch/pages/digital-screen-numbers-and-forecasts-to-2015-are-finalised.aspx | title=Digital Screen Numbers and Forecasts to 2015 are Finalised | work=IHS Technology | date=January 26, 2011 | access-date=September 1, 2016}}</ref> There were 10,083 d-screens in Europe as a whole (28.2 percent of global figure), 16,522 in the United States and Canada (46.2 percent of global figure) and 7,703 in Asia (21.6 percent of global figure). Worldwide progress was slower as in some territories, particularly Latin America and Africa.<ref>{{cite web|last=Romanek |first=Neal |url=http://www.screendaily.com/news/inaugural-uk-digital-cinema-conference-assesses-the-state-of-digital-cinema/5051676.article?blocktitle=ScreenTech&contentID=283 |title=Inaugural UK Digital Cinema Conference assesses the state of digital cinema | News | Screen |publisher=Screendaily.com |date=2013-02-07}}</ref><ref name="nj2012">{{cite web| title= Newtown's old-time movie house looks for revival in the digital age| url=http://www.nj.com/mercer/index.ssf/2012/03/newtowns_old-time_movie_house.html | date= March 19, 2012 | first=Joyce J. |last=Persico|work= [[The Times (Trenton)|The Times, Trenton]] | publisher= New Jersey On-Line LLC| access-date=2012-04-07}}</ref> As of 31 March 2015, 38,719 screens (out of a total of 39,789 screens) in the United States have been converted to digital, 3,007 screens in Canada have been converted, and 93,147 screens internationally have been converted.<ref name="natoonline.org">{{cite web|url=http://natoonline.org/initiatives/cinema-technologies/|title=Cinema Technologies|work=natoonline.org| access-date=September 1, 2016 |date=2013-07-20}}</ref> At the end of 2017, virtually all of the world's cinema screens were digital (98%).<ref>{{cite web |title=2017 THEME Report |url=https://www.mpaa.org/wp-content/uploads/2018/04/MPAA-THEME-Report-2017_Final.pdf |website=[[Motion Picture Association of America]]}}</ref>\n\nDespite the fact that today, virtually all global movie theaters have converted their screens to digital cinemas, some major motion pictures even as of 2019 are shot on film.<ref>{{Cite web|url=https://www.kodak.com/US/en/motion/customers/productions/default.htm|title=StackPath|website=www.kodak.com|access-date=2019-09-14}}</ref><ref>{{Cite web|url=https://filmmakermagazine.com/107353-23-films-35mm-released-in-2018/|title=24 Films Shot on 35mm Released in 2018|last=Rizov|first=Vadim|website=Filmmaker Magazine|language=en-US|access-date=2019-09-14}}</ref> For example, [[Quentin Tarantino]] released his latest film ''[[Once Upon a Time in Hollywood]]'' in 70 mm and 35 mm in selected theaters across the United States and Canada.<ref>{{Cite web|url=https://www.indiewire.com/2019/07/once-upon-a-time-in-hollywood-35-mm-70-mm-movie-theater-locations-quentin-tarantino-1202160721/|title=Where to See 'Once Upon a Time in Hollywood' on Celluloid, Quentin Tarantino's Preferred Format|last1=Brueggemann|first1=Tom|date=2019-07-24|website=IndieWire|access-date=2019-09-14}}</ref>"}},
{"article_title": "Electronic paper", "pageid": "9225", "revid": "1062503615", "timestamp": "2021-12-28T21:29:09Z", "history_paths": [["Electronic paper --- Introduction ---", "History"]], "categories": ["american inventions", "display technology", "electronic engineering", "electronic paper technology", "paper"], "heading_tree": {"Electronic paper --- Introduction ---": {"Technologies": {"Gyricon": {}, "Electrophoretic": {"Microencapsulated electrophoretic display": {}}, "Electrowetting": {"Electrofluidic": {}}, "Interferometric modulator (Mirasol)": {}, "Plasmonic electronic display": {}, "Other technologies": {}}, "History": {}, "Applications": {"Wristwatches": {}, "E-book readers": {}, "Newspapers": {}, "Displays embedded in smart cards": {}, "Status displays": {}, "Mobile phones": {}, "Electronic shelf labels": {}, "Public transport timetables": {}, "Digital signage": {}, "Computer monitor": {}, "Laptop": {}, "Electronic Tags": {}, "Other": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Electronic paper --- Introduction ---|History": "[[E Ink Corporation]] of E Ink Holdings Inc. released the first colored [[E Ink]] displays to be used in a marketed product. The [[Ectaco]] [[Ectaco jetBook|Jetbook Color]] was released in 2012 as the first colored electronic ink device, which used E Ink's Triton display technology.<ref name="jetbookk12.com">{{cite web|url=http://www.jetbookk12.com/|title=Ebook reader for education - ebook for schools, students, middle school. Educational ebook reader for learning - jetBook k-12 - ECTACO}}</ref><ref name="eink.com">{{cite web|url=https://www.eink.com/|title=E Ink}}</ref> E Ink in early 2015 also announced another color electronic ink technology called Prism.<ref name="gizmodo.com">{{cite web|url=https://gizmodo.com/color-changing-e-ink-is-here-but-not-in-ebook-readers-1677767392|title=Color-Changing E Ink Is Here, But Not In eBook Readers|first=Andrew|last=Liszewski}}</ref> This new technology is a color changing film that can be used for e-readers, but Prism is also marketed as a film that can be integrated into architectural design such as "wall, ceiling panel, or entire room instantly."<ref>{{cite web|url=https://www.eink.com/prism/about.html|title=About E Ink Prism|access-date=2015-11-28|archive-url=https://web.archive.org/web/20151208064955/http://www.eink.com/prism/about.html|archive-date=2015-12-08|url-status=dead}}</ref> The disadvantage of these current color displays is that they are considerably more expensive than standard E Ink displays. The JetBook Color costs roughly nine times more than other popular e-readers such as the Amazon Kindle.<ref name="jetbookk12.com"/><ref name="eink.com"/> As of January 2015, Prism had not been announced to be used in the plans for any e-reader devices.<ref name="gizmodo.com"/>"}},
{"article_title": "Engine", "pageid": "9640", "revid": "1058910146", "timestamp": "2021-12-06T09:17:47Z", "history_paths": [["Engine --- Introduction ---", "History"]], "categories": ["engine technology", "engines"], "heading_tree": {"Engine --- Introduction ---": {"Terminology": {}, "History": {"Antiquity": {}, "Medieval": {}, "Industrial Revolution": {}, "Automobiles": {"Horizontally opposed pistons": {}, "Advancement": {}, "Increasing power": {}, "Combustion efficiency": {}, "Engine configuration": {}}}, "Types": {"Heat engine": {"Combustion engine": {}, "Internal combustion engine": {}, "External combustion engine": {}, "Air-breathing combustion engines": {}, "Environmental effects": {}, "Air quality": {}, "Non-combusting heat engines": {}}, "Non-thermal chemically powered motor": {}, "Electric motor": {}, "Physically powered motor": {"Pneumatic motor": {}, "Hydraulic motor": {}, "Hybrid": {}}}, "Performance": {"Speed": {}, "Thrust": {}, "Torque": {}, "Power": {}, "Efficiency": {}, "Sound levels": {}}, "Engines by use": {}, "See also": {}, "References": {"Citations": {}, "Sources": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Engine --- Introduction ---|History": "[[Simple machine]]s, such as the [[Mace (bludgeon)|club]] and [[oar]] (examples of the [[lever]]), are [[Prehistory|prehistoric]]. More complex engines using [[human power]], [[Working animals|animal power]], [[Water wheel|water power]], [[Windmill|wind power]] and even steam power date back to antiquity. Human power was focused by the use of simple engines, such as the [[Capstan (nautical)|capstan]], [[windlass]] or [[Treadwheel|treadmill]], and with [[rope]]s, [[pulley]]s, and [[block and tackle]] arrangements; this power was transmitted usually with the forces [[mechanical advantage|multiplied]] and the speed [[gear reduction|reduced]]. These were used in [[Crane (machine)|cranes]] and aboard [[ship]]s in [[Ancient Greece]], as well as in [[Mining|mines]], [[Pump|water pumps]] and [[siege engines]] in [[Ancient Rome]]. The writers of those times, including [[Vitruvius]], [[Frontinus]] and [[Pliny the Elder]], treat these engines as commonplace, so their invention may be more ancient. By the 1st century AD, [[cattle]] and [[horse]]s were used in [[Mill (grinding)|mills]], driving machines similar to those powered by humans in earlier times.\n\nAccording to [[Strabo]], a water-powered mill was built in Kaberia of the [[Parthian Empire|kingdom of Mithridates]] during the 1st century BC. Use of [[water wheel]]s in mills spread throughout the [[Roman Empire]] over the next few centuries. Some were quite complex, with [[aqueduct (bridge)|aqueducts]], [[dam]]s, and [[sluice]]s to maintain and channel the water, along with systems of [[gears]], or toothed-wheels made of wood and metal to regulate the speed of rotation. More sophisticated small devices, such as the [[Antikythera Mechanism]] used complex trains of gears and dials to act as calendars or predict astronomical events. In a poem by [[Ausonius]] in the 4th century AD, he mentions a stone-cutting saw powered by water. [[Hero of Alexandria]] is credited with many such [[wind]] and [[steam]] powered machines in the 1st century AD, including the [[Aeolipile]] and the [[vending machine]], often these machines were associated with worship, such as animated altars and automated temple doors.\n\n Medieval Muslim engineers employed [[gear]]s in mills and water-raising machines, and used [[dam]]s as a source of water power to provide additional power to watermills and water-raising machines.<ref name="Hassan">{{cite book|first1=Ahmad Y. |last1=Hassan |author-link1=Ahmad Y. Hassan |url=http://www.history-science-technology.com/Articles/articles%2071.htm |work=Transfer Of Islamic Technology To The West, Part II |title=Transmission Of Islamic Engineering |url-status=dead |archive-url=https://web.archive.org/web/20080218171021/http://www.history-science-technology.com/Articles/articles%2071.htm |archive-date=2008-02-18 }}</ref> In the [[Islamic Golden Age|medieval Islamic world]], such advances made it possible to [[Mechanization|mechanize]] many industrial tasks previously carried out by [[manual labour]].\n\nIn 1206, [[al-Jazari]] employed a [[Crank (mechanism)|crank]]-[[conrod]] system for two of his water-raising machines. A rudimentary [[steam turbine]] device was described by [[Taqi al-Din Muhammad ibn Ma'ruf|Taqi al-Din]]<ref name="Hassan1">[[Ahmad Y Hassan|Hassan, Ahmad Y.]] (1976). ''Taqi al-Din and Arabic Mechanical Engineering'', pp. 34\u201335. Institute for the History of Arabic Science, [[University of Aleppo]].</ref> in 1551 and by [[Giovanni Branca]]<ref name="Giovanni">{{cite web|url=http://www.history.rochester.edu/steam/thurston/1878/Chapter1.html |title=University of Rochester, NY, ''The growth of the steam engine'' online history resource, chapter one |publisher=History.rochester.edu |access-date=2010-02-03 |url-status=dead |archive-url=https://web.archive.org/web/20120204034636/http://www.history.rochester.edu/steam/thurston/1878/Chapter1.html |archive-date=2012-02-04 }}</ref> in 1629.<ref>"''[https://books.google.com/books?id=Cv9LH4ckuEwC&pg=PA432&dq&hl=en#v=onepage&q=&f=false Power plant engineering]''". P.K. Nag (2002). [[Tata McGraw-Hill]]. p. 432. {{ISBN|0-07-043599-5}}</ref>\n\nIn the 13th century, the solid [[rocket motor]] was invented in China. Driven by gunpowder, this simplest form of internal combustion engine was unable to deliver sustained power, but was useful for propelling weaponry at high speeds towards enemies in battle and for [[fireworks]]. After invention, this innovation spread throughout Europe.\n\n [[Image:Boulton and Watt centrifugal governor-MJ.jpg|thumb|upright|Boulton & Watt engine of 1788]]\nThe [[Watt steam engine]] was the first type of steam engine to make use of steam at a pressure just above [[atmospheric pressure|atmospheric]] to drive the piston helped by a partial vacuum. Improving on the design of the 1712 [[Newcomen steam engine]], the Watt steam engine, developed sporadically from 1763 to 1775, was a great step in the development of the steam engine. Offering a dramatic increase in [[fuel efficiency]], [[James Watt]]'s design became synonymous with steam engines, due in no small part to his business partner, [[Matthew Boulton]]. It enabled rapid development of efficient semi-automated factories on a previously unimaginable scale in places where waterpower was not available. Later development led to [[steam locomotive]]s and great expansion of [[Rail transport|railway transportation]].\n\nAs for internal combustion piston engines, these were tested in France in 1807 by [[de Rivaz]] and independently, by the [[Nic\u00e9phore Ni\u00e9pce|Ni\u00e9pce brothers]]. They were theoretically advanced by [[Nicolas L\u00e9onard Sadi Carnot|Carnot]] in 1824.{{citation needed|date=May 2011}} In 1853\u201357 [[Eugenio Barsanti]] and [[Felice Matteucci]] invented and patented an engine using the free-piston principle that was possibly the first 4-cycle engine.<ref>{{cite web|title=La documentazione essenziale per l'attribuzione della scoperta|url=http://www.barsantiematteucci.it/inglese/documentiStorici.html|quote= A later request was presented to the Patent Office of the Reign of Piedmont, under No. 700 of Volume VII of that Office. The text of this patent request is not available, only a photo of the table containing a drawing of the engine. This may have been either a new patent or an extension of a patent granted three days earlier, on 30 December 1857, at Turin.}}</ref>\n\nThe invention of an [[internal combustion engine]] which was later commercially successful was made during 1860 by [[Etienne Lenoir]].<ref>Victor Albert Walter Hillier, Peter Coombes \u2013 [https://books.google.com/books?id=DoYaRsNFlEYC&pg=PA34&dq=cc+engine&hl=en&sa=X&ved=0ahUKEwjHtr7us63NAhVMIsAKHWeECxoQ6AEIIDAB#v=onepage&q=cc%20engine&f=false Hillier's Fundamentals of Motor Vehicle Technology, Book 1] Nelson Thornes, 2004  {{ISBN|0-7487-8082-3}} [Retrieved 2016-06-16]</ref>\n\nIn 1877 the [[Otto cycle]]  was capable of giving a far higher [[power to weight ratio]] than steam engines and worked much better for many transportation applications such as cars and aircraft.[[File:Mercedes V6 DTM Rennmotor 1996.jpg|thumb|upright=1.2|A V6 [[internal combustion engine]] from a [[Mercedes-Benz]]]]\n\n The first commercially successful automobile, created by [[Karl Benz]], added to the interest in light and powerful engines. The lightweight gasoline internal combustion engine, operating on a four-stroke Otto cycle, has been the most successful for light automobiles, while the more efficient [[Diesel engine]] is used for trucks and buses. However, in recent years, turbo Diesel engines have become increasingly popular, especially outside of the United States, even for quite small cars.\n\n In 1896, Karl Benz was granted a patent for his design of the first engine with horizontally opposed pistons. His design created an engine in which the corresponding pistons move in horizontal cylinders and reach top dead center simultaneously, thus automatically balancing each other with respect to their individual momentum. Engines of this design are often referred to as flat engines because of their shape and lower profile. They were used in the [[Volkswagen Beetle]], the [[Citro\u00ebn 2CV]], some Porsche and Subaru cars, many [[BMW]] and [[Honda]] [[motorcycle]]s, and propeller [[aircraft engine]]s.\n\n Continuance of the use of the internal combustion engine for automobiles is partly due to the improvement of engine control systems (onboard computers providing engine management processes, and electronically controlled fuel injection). Forced air induction by turbocharging and supercharging have increased power outputs and engine efficiencies. Similar changes have been applied to smaller diesel engines giving them almost the same power characteristics as gasoline engines. This is especially evident with the popularity of smaller diesel engine propelled cars in Europe. Larger diesel engines are still often used in trucks and heavy machinery, although they require special machining not available in most factories. Diesel engines produce lower [[hydrocarbon]] and {{CO2}} emissions, but greater [[Atmospheric particulate matter|particulate]] and {{NOx|link=yes}} pollution, than gasoline engines.<ref name=Harrison2001>{{Citation |title= Pollution: Causes, Effects and Control |first= Roy M. |last= Harrison |author-link=Roy M. Harrison|edition=4th |publisher= [[Royal Society of Chemistry]] |year= 2001 |isbn= 978-0-85404-621-8 }}</ref> Diesel engines are also 40% more fuel efficient than comparable gasoline engines.<ref name=Harrison2001/>\n\n In the first half of the 20th century, a trend of increasing engine power occurred, particularly in the U.S models.{{Clarify|reason=As opposed to what models?|date=June 2012}} Design changes incorporated all known methods of increasing engine capacity, including increasing the pressure in the cylinders to improve efficiency, increasing the size of the engine, and increasing the rate at which the engine produces work. The higher forces and pressures created by these changes created engine vibration and size problems that led to stiffer, more compact engines with V and opposed cylinder layouts replacing longer straight-line arrangements.\n\n Optimal combustion efficiency in passenger vehicles is reached with a coolant temperature of around {{convert|230|F|C|order=flip|0}}.<ref>{{Cite web|last=McKnight|first=Bill|date=August 2017|title=THE ELECTRICALLY ASSISTED THERMOSTAT|url=https://www.motor.com/magazine-summary/electrically-assisted-thermostat|url-status=live|access-date=2021-03-13|website=MOTOR|language=en-US}}</ref>\n\n Earlier automobile engine development produced a much larger range of engines than is in common use today. Engines have ranged from 1- to 16-cylinder designs with corresponding differences in overall size, weight, [[engine displacement]], and cylinder [[Bore (engine)|bores]]. Four cylinders and power ratings from 19 to 120 hp (14 to 90 kW) were followed in a majority of the models. Several three-cylinder, two-stroke-cycle models were built while most engines had straight or in-line cylinders. There were several V-type models and horizontally opposed two- and four-cylinder makes too. Overhead [[camshaft]]s were frequently employed. The smaller engines were commonly air-cooled and located at the rear of the vehicle; compression ratios were relatively low. The 1970s and 1980s saw an increased interest in improved [[Fuel economy in automobiles|fuel economy]], which caused a return to smaller V-6 and four-cylinder layouts, with as many as five valves per cylinder to improve efficiency. The [[Bugatti Veyron]] 16.4 operates with a [[W16 engine]], meaning that two [[V8 engine|V8]] cylinder layouts are positioned next to each other to create the W shape sharing the same crankshaft.\n\nThe largest internal combustion engine ever built is the [[W\u00e4rtsil\u00e4-Sulzer RTA96-C]], a 14-cylinder, 2-stroke turbocharged diesel engine that was designed to power the ''[[Emma M\u00e6rsk]]'', the largest container ship in the world when launched in 2006. This engine has a mass of 2,300 tonnes, and when running at 102 rpm (1.7 Hz) produces over 80 MW, and can use up to 250 tonnes of fuel per day."}},
{"article_title": "Fullerene", "pageid": "10628", "revid": "1061846068", "timestamp": "2021-12-24T10:28:14Z", "history_paths": [["Fullerene --- Introduction ---", "History"]], "categories": ["fullerenes", "emerging technologies"], "heading_tree": {"Fullerene --- Introduction ---": {"History": {"Predictions and limited observations": {}, "Discovery of {{chem|C|60}}": {}, "Further developments": {}}, "Types": {"Buckyballs": {"Buckminsterfullerene": {}, "Other fullerenes": {}}, "Carbon nanotubes": {}}, "Derivatives": {}, "Heterofullerenes and non-carbon fullerenes": {"Silicon": {}, "Boron": {}, "Other elements": {}}, "Main fullerenes": {}, "Properties": {"Topology": {}, "Bonding": {}, "Encapsulation": {}, "Research": {}, "Aromaticity": {}}, "Reactions": {"Polymerization": {}, "Chemistry": {}, "Solubility": {}, "Quantum mechanics": {}, "Superconductivity": {}, "Chirality": {}, "Stability": {}}, "Systematic naming": {}, "Production": {}, "Applications": {"Medical research": {}, "Tumor research": {}}, "Safety and toxicity": {}, "Popular culture": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Fullerene --- Introduction ---|History": "[[Image:Fullerene c540.png|thumb|The [[icosahedron|icosahedral]] fullerene {{chem|C|540}}, another member of the family of fullerenes]]\n\n The icosahedral {{chem|C|60|H|60}} cage was mentioned in 1965 as a possible topological structure.<ref name=schultz1965/> [[Eiji Osawa]] predicted the  existence of {{chem|C|60}} in 1970.<ref name=osawa1970/><ref name=half2006/> He noticed that the structure of a [[corannulene]] molecule was a subset of the shape of a football, and hypothesised that a full ball shape could also exist. Japanese scientific journals reported his idea, but neither it nor any translations of it reached Europe or the Americas.\n\nAlso in 1970, [[R. W. Henson]] (then of the [[United Kingdom|UK]] [[Atomic Energy Research Establishment]]) proposed the  {{chem|C|60}} structure and made a model of it. Unfortunately, the evidence for that new form of carbon was very weak at the time, so the proposal was met with skepticism, and was never published.  It was acknowledged only in 1999.<ref name=throw1999/><ref name=hens2013/>\n\nIn 1973, independently from Henson, a group of scientists from the USSR made a quantum-chemical analysis of the stability of {{chem|C|60}} and calculated its electronic structure. The paper was published in 1973,<ref name=boch1973/> but the scientific community did not give much importance to this theoretical prediction.\n\nAround 1980, [[Sumio Iijima]] identified the molecule of {{chem|C|60}} from an electron microscope image of [[carbon black]], where it formed the core of a particle with the structure of a "bucky onion".<ref name=iji1980/>\n\n In 1985, [[Harold Kroto]] of the [[University of Sussex]], working with [[James R. Heath]], [[Sean O'Brien (scientist)|Sean O'Brien]], [[Robert Curl]] and [[Richard Smalley]] from [[Rice University]], discovered fullerenes in the sooty residue created by vaporising carbon in a [[helium]] atmosphere.  In the [[mass spectrometry|mass spectrum]] of the product, discrete peaks appeared corresponding to molecules with the exact mass of sixty or seventy or more carbon atoms, namely {{chem|C|60}} and {{chem|C|70}}. The team identified their structure as the now familiar "buckyballs".<ref name=kroto1985/>\n\nThe name "buckminsterfullerene" was eventually chosen for {{chem|C|60}} by the discoverers as an homage to [[American people|American]] [[architect]] [[Buckminster Fuller]] for the vague similarity of the structure to the [[geodesic dome]]s which he popularized; which, if they were extended to a full sphere, would also have the icosahedral symmetry group.<ref name=webBris/> The "ene" ending was chosen to indicate that the carbons are [[saturated hydrocarbon|unsaturated]], being connected to only three other atoms instead of the normal four.  The shortened name "fullerene" eventually came to be applied to the whole family.\n\nKroto, Curl, and Smalley were awarded the 1996 [[Nobel Prize in Chemistry]]<ref name=nob1966/> for their roles in the discovery of this class of molecules.\n\n Kroto and the Rice team already discovered other fullerenes besides C<sub>60</sub>,<ref name=kroto1985/> and the list was much expanded in the following years.  Carbon nanotubes [[Carbon nanotubes#Discovery|were first discovered and synthesized]] in 1991.<ref name=mraz2005/><ref name=iji1991b/>\n\nAfter their discovery, minute quantities of fullerenes were found to be produced in [[soot|sooty flames]],<ref>{{Cite journal|last1=Reilly|first1=P. T. A.|last2=Gieray|first2=R. A.|last3=Whitten|first3=W. B.|last4=Ramsey|first4=J. M.|date=2000|title=Fullerene Evolution in Flame-Generated Soot|url=https://pubs.acs.org/doi/10.1021/ja003521v|journal=Journal of the American Chemical Society|language=en|volume=122|issue=47|pages=11596\u201311601|doi=10.1021/ja003521v|issn=0002-7863}}</ref> and by [[lightning]] discharges in the atmosphere.<ref name=invWeb2010/>  In 1992, fullerenes were found in a family of mineraloids known as [[shungite]]s in [[Karelia]], Russia.<ref name=buseck1992/>\n\nThe production techniques were improved by many scientists, including [[Donald Huffman]], [[Wolfgang Kr\u00e4tschmer]], [[Lowell D. Lamb]], and [[Konstantinos Fostiropoulos]].<ref>{{Cite journal|last1=Kr\u00e4tschmer|first1=W.|last2=Lamb|first2=Lowell D.|last3=Fostiropoulos|first3=K.|last4=Huffman|first4=Donald R.|date=1990|title=Solid C60: a new form of carbon|url=http://www.nature.com/articles/347354a0|journal=Nature|language=en|volume=347|issue=6291|pages=354\u2013358|doi=10.1038/347354a0|bibcode=1990Natur.347..354K|s2cid=4359360|issn=0028-0836}}</ref>  Thanks to their efforts, by 1990 it was relatively easy to produce gram-sized samples of fullerene powder. [[Fullerene purification]] remains a challenge to chemists and to a large extent determines fullerene prices.\n\nIn 2010, the [[spectrum|spectral signatures]] of C<sub>60</sub> and C<sub>70</sub> were observed by NASA's [[Spitzer Space Telescope|Spitzer]] infrared telescope in a cloud of cosmic dust surrounding a star 6500 light years away.<ref name=cami2010/>  Kroto commented: "This most exciting breakthrough provides convincing evidence that the buckyball has, as I long suspected, existed since time immemorial in the dark recesses of our galaxy."<ref name=bbc2010/> According to astronomer Letizia Stanghellini, "It\u2019s possible that buckyballs from outer space provided seeds for life on Earth."<ref name=atkin2010/>   In 2019, ionized C<sub>60</sub> molecules were detected with the [[Hubble Space Telescope]] in the space between those stars.<ref name="SA-20190429">{{cite news |last=Starr |first=Michelle |title=The Hubble Space Telescope Has Just Found Solid Evidence of Interstellar Buckyballs |url=https://www.sciencealert.com/the-hubble-space-telescope-has-found-evidence-of-interstellar-buckyballs |date=29 April 2019 |work=ScienceAlert.com |access-date=29 April 2019 }}</ref><ref name="AJL-20190422">{{cite journal |author=Cordiner, M.A. |display-authors=et al. |title=Confirming Interstellar C60 + Using the Hubble Space Telescope |date=22 April 2019 |journal=[[The Astrophysical Journal Letters]] |volume=875 |pages=L28 |number=2 |doi=10.3847/2041-8213/ab14e5 |arxiv=1904.08821 |bibcode=2019ApJ...875L..28C |s2cid=121292704 }}</ref>"}},
{"article_title": "Flying car", "pageid": "10773", "revid": "1058477298", "timestamp": "2021-12-03T19:31:14Z", "history_paths": [["Flying car --- Introduction ---", "History"]], "categories": ["roadable aircraft", "emerging technologies"], "heading_tree": {"Flying car --- Introduction ---": {"History": {"Early 20th century": {}, "Late 20th century": {}, "Early 21st century": {}}, "Design": {"Lift": {}, "Power": {}, "Safety": {}, "Control": {}, "Environment": {}, "Cost": {}}, "Industry groups": {}, "List of flying cars": {}, "Popular culture": {"Anticipation": {}, "Where's my flying car?": {}, "Fictional flying cars": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Flying car --- Introduction ---|History": "Aircraft designer [[Glenn Curtiss]] built his [[Curtiss Autoplane|Autoplane]] in 1917. It had a pusher propeller for flight, with removable flight surfaces including a triplane wing, canard foreplane and twin tails. It was able to hop, but not fly.<ref name="Time-never-come">{{cite news |url=https://www.nytimes.com/2009/04/12/weekinreview/12vinciguerra.html |work=[[The New York Times]] |title=Flying Cars: An Idea Whose Time Has Never Come |author=Thomas Vinciguerra |author-link=Thomas Vinciguerra |date=April 11, 2009}}</ref>\n\nIn 1935, inventor Constantinos Vlachos built a prototype of a 'tri-phibian' vehicle, but it caught fire after the engine exploded, while Vlachos was demonstrating it in [[Washington, D.C.]] Vlachos' prototype is most notable for a [[newsreel]] that captured the incident,<ref>{{YouTube|IuJMU2apQZo|Newsreel of flying car on fire}}</ref> which left him in hospital for several months.<ref>{{cite magazine|title=News Cameras Film Thrilling Rescue|url=https://archive.org/details/bub_gb_eyYDAAAAMBAJ\n|quote=constantinos vlachos popular science.|page=[https://archive.org/details/bub_gb_eyYDAAAAMBAJ/page/n38 29]|magazine=Popular Science|date=January 1936}}</ref><ref>{{cite journal|title=Hard-Luck Vlachos|url=http://blog.hemmings.com/index.php/2008/05/18/sia-flashback-a-day-with-the-scrapper-and-hard-luck-vlachos/|page=44|publisher=Special-Interest Autos|date=July 1974}}</ref>\n\nThe [[Autogiro Company of America AC-35]] was an early attempt at a roadable aircraft.  On March 26, 1936, the AC-35 was flown by test pilot James G. Ray with counter-rotating propellers. These were later replaced with a single conventional propeller arrangement.  On October 2, 1936, Ray landed the AC-35 in a downtown park in [[Washington, D.C.]] where it was displayed.  On October 26, 1936, the aircraft was converted to roadable configuration.<ref>{{cite book |title=Realizing the dream of flight: biographical essays in honor of the centennial of flight, 1903\u20132003 |last1=Dawson |first1=Virginia |first2=Mark D. |last2=Bowles  |year=2005 |publisher=National Aeronautics and Space Administration, NASA History Division, Office of External Relations |asin=B002Y26TM0  |page=70}}</ref>  Ray drove it to the main entrance of the Commerce Building, where it was accepted by John H. Geisse, chief of the Aeronautics Branch.  Although it was successfully tested, it did not enter production.\n\nThe first roadable fixed wing aircraft actually to fly was built by [[Waldo Waterman]]. Waterman was associated with Curtiss while Curtiss was pioneering [[amphibious aircraft]] at North Island on [[San Diego Bay]] in the 1910s. On March 21, 1937, Waterman's [[Waterman Arrowbile|Arrowbile]] first took to the air.<ref>{{cite journal|url= https://books.google.com/books?id=WScDAAAAMBAJ&q=%22Plane%20Sheds%20Wing%20To%20Run%20On%20Ground&pg=PA52 |title=Plane Sheds Wing To Run On Ground|journal=Popular Science|date=May 1937}}</ref> The Arrowbile was a development of Waterman's tailless aircraft, the [[Waterman Whatsit|Whatsit]].<ref>[https://books.google.com/books?id=wygDAAAAMBAJ&pg=PA39&dq=Popular+Science+1931+plane&hl=en&ei=cIEUTfeLIcienAf0wdWFDg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCIQ6AEwADge#v=onepage&q=Popular%20Science%201931%20plane&f=true "Tailless Flivver Plane Has Pusher Propeller"] ''Popular Science'', May 1934, rare photos in article</ref>  It had a wingspan of {{convert|38|ft|m}} and a length of {{convert|20|ft|6|in|m}}. On the ground and in the air it was powered by a [[Studebaker]] engine. It could fly at {{convert|112|mph|km/h|abbr=on}} and drive at {{convert|56|mph|km/h|abbr=on}}.\n\nIn 1942, the British army built the [[Hafner Rotabuggy]], an experimental roadable autogyro that was developed with the intention of producing a way of air-dropping off-road vehicles. Although initial tests showed that the Rotabuggy was prone to severe vibration at speeds greater than {{convert|45|mph|km/h|0}}, with improvements the Rotabuggy achieved a flight speed of {{convert|70|mph|km/h|0|abbr=on}}. However, the introduction of [[Military glider|gliders]] that could carry vehicles (such as the [[Waco CG-4|Waco Hadrian]] and [[Airspeed Horsa]]) led to the project's cancellation.<ref>{{cite book |title=Jeeps 1941\u201345 |first=Steven J. |last=Zaloga |pages=37\u201338 |url= https://books.google.com/books?id=I_fFkOS4b_4C&q=Rotabuggy+&pg=PA38 |publisher=Osprey Publishing |year=2005 |isbn=1-84176-888-X}}</ref>\n\n Although several designs (such as the ConVairCar) have flown, none have enjoyed commercial success, and those that have flown are not widely known by the general public. The most successful example, in that several were made and one is still flying, is the 1949 [[Taylor Aerocar]].\n\nIn 1946, the Fulton FA-2 [[Fulton Airphibian|Airphibian]] was an American made flying car designed by [[Robert Edison Fulton Jr.]], it was an aluminum-bodied car, built with independent suspension, aircraft-sized wheels, and a six-cylinder 165 hp engine. The fabric wings were easily attached to the fuselage, converting the car into a plane. Four prototypes were built. [[Charles Lindbergh]] flew it 1950 and, although it was not a commercial success (financial costs of [[airworthiness]] certification forced him to relinquish control of the company, which never developed it further), it is now in the [[Smithsonian]].\n\n[[File:Aerocar at EAA.jpg|thumb|1949 [[Aerocar]] with wings folded, at the [[EAA AirVenture Museum]]]]\nThe [[Aerocar]], designed and built by [[Molt Taylor]], made a successful flight in December 1949, and in following years versions underwent a series of road and flying tests. [[Chuck Berry]] featured the concept in his 1956 song "[[You Can't Catch Me]]", and in December 1956 the [[Civil Aviation Authority]] approved the design for mass production, but despite wide publicity and an improved version produced in 1989, Taylor did not succeed in getting the flying car into production. In total, six Aerocars were built. It is considered to be one of the first practical flying cars.<ref name="Glass2015">{{cite book|author=Andrew Glass|title=Flying Cars: The True Story|url=https://books.google.com/books?id=dFBVCgAAQBAJ&pg=PA84|date=25 August 2015|publisher=Houghton Mifflin Harcourt|isbn=978-0-547-53423-7|pages=84\u2013}}</ref>\n\nOne notable design was Henry Smolinski's [[AVE Mizar|Mizar]], made by mating the rear end of a [[Cessna Skymaster]] with a [[Ford Pinto]], but it disintegrated during test flights killing Smolinski and the pilot.\n\nMoller began developing VTOL craft in the late 1960s, but no Moller vehicle has ever achieved free flight out of ground effect. The [[Moller Skycar M400]]<ref>{{cite web|author=Category: Uncategorised |url=http://www.moller.com |title=Moller International Home |website=Moller.com |date=26 September 2012 |access-date=24 January 2014}}</ref><ref>{{cite web|url=https://www.flightglobal.com/pdfarchive/view/2002/2002%20-%203737.html?search=Flying%20car |title=''Flight'' 2002 |website=Flightglobal.com |access-date=19 October 2018}}</ref> was a project for a personal [[VTOL]] (vertical take-off and landing) aircraft which is powered by four pairs of in-tandem [[Wankel rotary engine]]s. The proposed Autovolantor model had an all-electric version powered by [[Altairnano]] batteries.<ref>{{cite web |url=http://blog.autoforsale.co.in/2014/07/rinspeed-squba-first-underwater-flying.html |archive-url=https://web.archive.org/web/20140718165427/http://blog.autoforsale.co.in/2014/07/rinspeed-squba-first-underwater-flying.html |url-status=dead |archive-date=18 July 2014 |title=Rinspeed Squba, The First Underwater Flying Car |website=autoforsale.co.in |access-date=13 August 2014 }}</ref> The company has been dormant since 2015.\n\nIn the mid-1980s, former [[Boeing]] engineer Fred Barker founded Flight Innovations Inc. and began the development of the Sky Commuter, a small duct fans-based VTOL aircraft. It was a compact, {{convert|14|ft|m|adj=mid|-long}} two-passenger and was made primarily of composite materials.<ref>{{cite web|url=http://www.highbeam.com/doc/1G1-9302266.html|archive-url=https://web.archive.org/web/20150323093810/http://www.highbeam.com/doc/1G1-9302266.html|url-status=dead|archive-date=23 March 2015|title=Vest-pocket VTOL. (vertical take-off-and-landing aircraft, Sky Commuter) (column)|publisher=Mechanical Engineering-CIME|date=1 December 1990|access-date=1 October 2014}}</ref> In 2008, the remaining prototype was sold for \u00a386k on [[eBay]].<ref>{{cite web|url=http://boingboing.net/2008/01/12/sky-commuter-vehicle.html|title=Sky Commuter vehicle prototype for sale|website=Urbanaero.com |date=12 January 2012|access-date=1 October 2014}}</ref>\n\n [[File:Parajet Skycar at NEC Birmingham.jpg|right|thumb|[[Parajet Skycar]] prototype seen at the Sport and Leisure Aviation Show (SPLASH), Birmingham, UK, November 2008]]\n[[File:Terrafugia_--_2012_NYIAS_cropped.jpg|thumb|Production prototype of [[Terrafugia Transition]] at the [[New York International Auto Show|N.Y. Int'l Auto Show]] in April 2012]]\n[[File:SuperSkyCycle.jpg|thumb|[[The Butterfly Super Sky Cycle|Super Sky Cycle]]]]\n[[File:Maverick Flying Car.jpg|thumb|[[I-TEC Maverick|Maverick Flying Dune Buggy]]]]\n[[File:PD-1 Roadable Glastar.jpg|thumb|[[Plane Driven PD-1 Roadable Glastar]]]]\n\nIn 2009 the U.S., the [[DARPA|Defense Advanced Research Projects Agency]] (DARPA) initiated the $65 million [[Transformer (flying car)|Transformer]] program to develop a four-person roadable aircraft by 2015.<ref>Warwick, Graham.  [http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog%3aa68cb417-3364-4fbf-a9dd-4feda680ec9c&plckPostId=Blog%3aa68cb417-3364-4fbf-a9dd-4feda680ec9cPost%3accef0189-116b-4626-a4a8-d26cbd2f7fa8 Leading Edge blog: DARPA's Transformer - a Humvee That Flies] {{Webarchive|url=https://web.archive.org/web/20131023115418/http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:a68cb417-3364-4fbf-a9dd-4feda680ec9c |date=2013-10-23 }}, AW&ST On Technology, ''[[Aviation Week]]'' online website, April 16, 2010. Retrieved May 10, 2013.</ref> The vehicle was to have had VTOL capability and a {{convert|280|mi|km|adj=mid}} range. [[AAI Corporation]] and [[Lockheed Martin]] were awarded contracts.<ref>{{cite magazine|last=Warwick|first=Graham|title=Is Darpa's Fly-Drive Transformer on the Right Road?|url=http://www.aviationweek.com/Blogs.aspx?plckBlogId=blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post:37ed3841-153e-4d86-950c-3b027e3d2ea2|magazine=Aviation Week|access-date=3 September 2013|archive-url=https://web.archive.org/web/20130910192542/http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7|archive-date=10 September 2013|url-status=dead|df=dmy-all}}</ref> The program was cancelled in 2013.\n\nThe [[Parajet Skycar]] utilises a [[paramotor]] for propulsion and a [[parafoil]] for lift. The main body consists of a modified dune buggy. It has a top speed of {{convert|80|mi/h|km/h|abbr=on}} and a maximum range of {{convert|180|mi|km}} in flight. On the ground it has a top speed of {{convert|112|mi/h|km/h|abbr=on}} and a maximum range of {{convert|249|mi|km}}. Parajet flew and drove its prototype from [[London]] to [[Timbuktu]] in January 2009.\n\nThe [[I-TEC Maverick|Maverick Flying Dune Buggy]] was designed by the [[Indigenous People's Technology and Education Center]] of Florida as an off-road vehicle that could unfurl an advanced parachute and then travel by air over impassable terrain when roadways were no longer usable. The {{convert|1100|lb|kg|adj=mid}} 'Maverick' vehicle is powered by a {{convert|128|hp|abbr=on}} engine that can also drive a five-bladed pusher [[Propeller (aircraft)|propeller]]. It was initially conceived in order to help [[Christian ministry|minister]] to remote [[Amazon Rainforest|Amazon rainforest]] communities, but will also be marketed for visual [[pipeline transport|pipeline inspection]] and other similar activities in desolate areas or difficult terrain.<ref>Logan Ward, [http://www.popularmechanics.com/automotive/new_cars/4332920.html 10 Most Brilliant Innovators of 2009: I-TEC\u2019s Flying Dune Buggy] {{Webarchive|url=https://web.archive.org/web/20100212152710/http://www.popularmechanics.com/automotive/new_cars/4332920.html |date=2010-02-12 }}, Popular Mechanics, November 2009. Retrieved 25 October 2009.</ref>\n\nThe [[Plane Driven PD-1 Roadable Glastar]] is a modification to the Glastar Sportsman GS-2 to make a practical roadable aircraft. The approach is novel in that it uses a mostly stock aircraft with a modified landing gear "pod" that carries the engine for road propulsion. The wings fold along the side, and the main landing gear and engine pod slide aft in driving configuration to compensate for the rearward center of gravity with the wings folded, and provide additional stability for road travel.<ref>{{cite journal|journal=Sport Aviation|title=The PD-1 Roadable Glastar|author=Budd Davisson|date=October 2010}}</ref><ref>{{cite web|title=Company Moves On Transformative Roadable Glasair|url=http://www.avweb.com/avwebflash/news/plane_driven_roadable_aircraft_pdx_203489-1.html|access-date=22 October 2010}}</ref>\n\nThe [[Butterfly Super Sky Cycle|Super Sky Cycle]] was an American [[Homebuilt aircraft|homebuilt]] roadable [[gyroplane]] designed and manufactured by [[The Butterfly Aircraft LLC]].<!-- Time Magazine Vol.116 No.16 dates back to October 20, 1980 <ref>{{cite journal|magazine=Time Magazine|volume=116|issue=16|page=16}}</ref>--><ref name=sscGiz>Blain, Loz. [http://www.gizmag.com/go/7135/ "The flying motorcycle - road-registered and available now"] ''GizMag'', 17 April 2007. Retrieved 4 April 2012.</ref> It is a registered [[motorcycle]].<ref name=sscTel>[https://www.telegraph.co.uk/news/picturegalleries/picturesoftheday/8878687/Pictures-of-the-day-9-November-2011.html?image=5 "Pictures of the day"] ''[[The Daily Telegraph]]'', 9 November 2011. Retrieved 4 April 2012.</ref>\n\nKitty Hawk Flyer by [[Kitty Hawk Corporation]] \u2014 [[Larry Page]]'s Zee.Aero and the [[Kitty Hawk Corporation]] (backed by Page) are developing flying cars.<ref>{{cite magazine|last1=Vance|first1=Ashlee|last2=Stone|first2=Brad|\ntitle=Welcome to Larry Page's Secret Flying-Car Factories|url=https://www.bloomberg.com/news/articles/2016-06-09/welcome-to-larry-page-s-secret-flying-car-factories|access-date=12 March 2017|magazine=Bloomberg Businessweek|date=9 June 2016}}</ref><ref>{{cite web|author=by \u0d38\u0d4d\u0d35\u0d28\u0d4d\u0d24\u0d02 \u0d32\u0d47\u0d16\u0d15\u0d7b |url=http://www.manoramaonline.com/news/just-in/2017/04/25/personal-flying-machine-maker-plans-deliveries-this-year.html |title=Flying Cars |website=Manoramaonline.com |date=25 April 2017 |access-date=19 October 2018}}</ref> In April 2017, Kitty Hawk unveiled its "Flyer" VTOL craft, which flies only over water. Part of Kitty Hawk was split off into [[Cora by Wisk]], a joint venture between Wisk Aero LLC and [[Boeing]], in 2019.<ref>{{Cite web|url=https://www.geekwire.com/2019/ups-downs-boeing-kitty-hawk-reboot-flying-car-venture-wisk/|title=After ups and downs, Boeing and Kitty Hawk reboot flying-car venture as Wisk|date=3 December 2019|website=GeekWire}}</ref><ref name=BI-2017/>\n\n[[Volocopter 2X]] by E-Volo, now [[Volocopter]]<ref name=BI-2017/> \u2014 in August 2019, the Volocopter 2X was successfully tested at [[Helsinki airport]] for integrate with air traffic management services for unpiloted aerial craft AirMap, Altitude Angel and [[Unifly]], a key element for commercial flight certification.<ref>{{Cite web|url=https://social.techcrunch.com/2019/08/30/volocopters-2x-evtol-records-a-first-with-flight-at-helsinki-international-airport/|title=Volocopter's 2X eVTOL records a first with flight at Helsinki International Airport}}</ref>\n\n[[EHang#EHang 216|EHang 216]] by [[EHang]]<ref name=BI-2017/> \u2014 the EHang 216 carried passengers in [[Changchun]], China during a demonstration flight at the 2019 China-Northeast Asia Expo in late August 2019<ref>{{Cite web|url=https://evtol.com/news/video-ehang-216-flying-passengers-in-china/|title=Watch the EHang 216 fly with passengers in China}}</ref>\n\n[[Uber]] \u2014 the international [[ride-sharing]] company is working with [[Karem Aircraft]]<ref>{{Cite web|url=https://social.techcrunch.com/2018/05/08/uberair-adds-another-flying-taxi-partner/|title=Uber adds another flying taxi partner}}</ref> to develop the electric eCRM-003 eVTOL, with first tests expected by 2020, and very limited UberAir service trials by 2023 (Los Angeles, Dallas-Fort Worth, and Melbourne), with 50 vehicles serving five skyports per city.<ref>{{Cite news|url=https://www.cnet.com/news/how-uber-is-getting-flying-cars-off-the-ground/|title=How Uber is getting flying cars off the ground|last=Reilly|first=Claire|date=25 September 2018|work=CNET|access-date=27 September 2018|language=en|ref=UberAir: 2023 3-city trials \u2013 Sep. 2018 CNET}}</ref><ref>{{Cite news|url=https://techcrunch.com/2019/06/12/uber-airs-plan-to-get-you-from-a-skyport-to-an-airport/|title=Uber Air's plan to get you from a skyport to an airport|last=Dickey|first=Megan|date=12 June 2019|work=TechCrunch|access-date=12 June 2019|language=en}}</ref>\n\nSky Drive by Cartivator \u2014 the [[start-up]] had announced its goal of a flight to ignite the [[2020 Summer Olympics]] [[Olympic torch|torch]] with its [[eVTOL]],<ref name=BI-2017>{{Cite web|url=https://www.businessinsider.com/flying-cars-companies-2020-2017-6|title=These 7 companies are looking to make 'flying cars' a reality by 2020|first=Danielle|last=Muoio|website=Business Insider}}</ref> postponed to due to the [[COVID-19 pandemic]].<ref>{{Cite web|url=https://www.olympic.org/news/ioc-ipc-tokyo-2020-organising-committee-and-tokyo-metropolitan-government-announce-new-dates-for-the-olympic-and-paralympic-games-tokyo-2020|title=IOC, IPC, Tokyo 2020 Organising Committee and Tokyo Metropolitan Government announce new dates for the Olympic and Paralympic Games Tokyo 2020 \u2013 Olympic News|date=30 March 2020|website=International Olympic Committee}}</ref> [[Toyota]] is a backer.<ref name=BI-2017/> In August 2020, a startup in Japan backed by Toyota tested its flying car prototype, which was a quadcopter with 2 propellers and motors per corner that flew for four minutes.<ref>{{Cite web|url=https://www.engadget.com/skydrive-flying-car-test-flight-195528927.html|title=Watch a Toyota-backed flying car's first public, piloted test flight|website=Engadget}}</ref><ref>{{Cite web|last=Johnson|first=Lauren M.|date=|title=Japanese company successfully tests a manned flying car for the first time|url=https://www.cnn.com/2020/08/29/us/flying-car-successful-test-in-japan-trnd/index.html|url-status=live|archive-url=|archive-date=|access-date=|website=CNN}}</ref>\n\nTurkey's top UAV producer Baykar is focusing on working on its flying car named Cezeri. It was first introduced on TEKNOFEST Istanbul in 2019.\n\nAt the 2014 Pioneers Festival at Wien (Austria) [[AeroMobil]] presented their version 3.0 of their flying car. The prototype was conceived as a vehicle that can be converted from an automobile to an aircraft. The version 2.5 proof-of-concept took 20 years to develop and first flew in 2013. CEO Juraj Vaculik said that the company planned to move flying cars to market: "the plan is that in 2017 we'll be able to announce\u2026 the first flying roadster."<ref>{{cite web|last1=Mack|first1=Eric|title=Finally! A Flying Car Could Go On Sale By 2017|url=https://www.forbes.com/sites/ericmack/2015/03/16/finally-a-flying-car-could-go-on-sale-as-soon-as-2017/|website=Forbes|access-date=17 March 2015}}</ref> In 2016, AeroMobil was test-flying a prototype that obtained Slovak [[Ultralight aviation|ultralight]] certification. When the final product will be available or how much it will cost is not yet specified.<ref name="aeromobil">{{cite web|url=http://aeromobil.com/ |title=AeroMobil: Flying car |website=aeromobil.com |access-date=9 August 2016}}</ref> In 2018, it unveiled a concept that resembled a flying sportscar with VTOL capability.<ref>\n{{Cite web|url=https://www.nbcnews.com/mach/science/will-futuristic-flying-car-ever-get-ground-ncna859171|title=Will this futuristic flying car ever get off the ground?|website=NBC News}}</ref> \nThe [[Aeromobil]] <!--not [[AeroMobile]]-->2.5 has folding wings and a Rotax 912 engine. It can travel at {{convert|124|mph|order=flip}} with a range of {{convert|430|mi|order=flip}}, and flew for the first time in 2013.<ref>ALYSSA DANIGELIS. "[http://news.discovery.com/autos/future-of-transportation/slovakian-flying-car-prototype-takes-off-131021.htm Slovakian Flying Car Prototype Takes Off]" ''[[Discovery News]]'', OCT 21, 2013. Accessed: 22 October 2013.</ref><ref>{{Cite web|url=https://www.nyteknik.se/popularteknik/har-lyfter-en-ny-flygbil-6401976|title=H\u00e4r lyfter en ny flygbil|first=Jan|last=Melin|website=Ny Teknik}}</ref> On October 29, 2014, Slovak startup AeroMobil s.r.o. unveiled [[AeroMobil s.r.o. AeroMobil|AeroMobil 3.0]]<ref name="aeromobil"/> \nat Vienna Pioneers Festival.<ref>{{cite web|url=https://venturebeat.com/2014/10/29/silicon-valley-can-keep-its-teslas-and-robotic-cars-slovakias-aeromobil-just-unveiled-a-flying-car |title=VB |website=venturebeat.com |access-date=2014-10-30}}</ref>\n\nKlein Vision in [[Slovakia]] have developed a prototype [[Klein Vision AirCar|AirCar]], which drives like a sports car and for flight has a pusher propeller with twin tailbooms, and foldout wings. In June 2021, the prototype carried out a 35-minute flight between airports.<ref>Zoe Kleinman; "[https://www.bbc.co.uk/news/technology-57651843 Flying car completes test flight between airports]", BBC, 30 June 2021.</ref><ref>{{Cite web|url=https://www.klein-vision.com/|title=Klein Vision \u2013 Flying Car}}</ref>\n\nThe [[Terrafugia Transition]] is under development by a private company founded by MIT graduates.<ref>{{cite web|url=http://www.terrafugia.com/ |title=Terrafugia, Inc |website=Terrafugia.com |access-date=2010-10-07}}</ref> It is a roadable aircraft that the company describes as a "Personal Air Vehicle". The aircraft can fold its wings in 30 seconds and drive the front wheels, enabling it to operate as a traditional road vehicle and as a general aviation aeroplane. The company planned to release its Transition "[[Personal Air Vehicle]]" to customers in late 2011. An operational prototype was displayed at [[EAA AirVenture Oshkosh|Oshkosh]] in 2008<ref>{{cite web|url=http://www.airventure.org/news/2008/7sat2/terrafugia.html |title=Terrafugia ready for road, flight testing |website=Airventure.org |date=2008-08-02 |access-date=2010-04-15}}</ref> and its first flight occurred on 2009-03-05.<ref>{{cite web|last=Haines |first=Thomas B. |url=http://www.aopa.org/aircraft/articles/2009/090319terrafugia.html |title=AOPA Online: First roadable airplane takes flight |website=Aopa.org |access-date=2010-04-15}}</ref> Owners will drive the car from their garage to an airport where they will then be able to fly within a range of {{convert|500|mi|km|abbr=on}}. It will carry two people plus luggage and its [[Rotax 912#Specifications (Rotax 912S ULS)|Rotax 912S]] engine operates on premium unleaded gas.<ref>{{citation|publisher=The New York Times|title=For $279,000, Terrafugia Transition Puts the Wind Beneath Your Wings|date=April 5, 2012|work=Wheels blog|author=Jerry Garrett|url=http://wheels.blogs.nytimes.com/2012/04/05/for-279000-terrafugia-transition-puts-the-wind-beneath-your-wings/|access-date=2013-04-20}}</ref> It was approved by the [[FAA]] in June 2010,<ref>{{cite news|last=O'Carroll|first=Eoin|title=Flying Car – just like the Jetsons – gets green light from FAA|url=http://www.csmonitor.com/Science/2010/0629/Flying-Car-just-like-the-Jetsons-gets-green-light-from-FAA-VIDEO|newspaper=The Christian Science Monitor|access-date=25 August 2013}}</ref> and its anticipated base purchase price is $279,000.<ref>{{cite web|title=The Transition|url= http://www.terrafugia.com/aircraft/transitionR|website=Terrafugia.com |access-date=25 August 2013|url-status=dead|archive-url= https://web.archive.org/web/20130829145905/http://www.terrafugia.com/aircraft/transitionR|archive-date=29 August 2013}}</ref> On 7 May 2013, [[Terrafugia]] announced the [[Terrafugia TF-X|TF-X]], a plug-in hybrid tilt-rotor vehicle that would be the first fully autonomous flying car. It would have a range of {{convert|500|miles|km}} per flight and batteries are rechargeable by the engine. Development of TF-X is expected to last many years.\n\nThe production-ready single-engine, roadable [[PAL-V Liberty]] autogyro, or [[gyrocopter]], debuted at the [[Geneva Motor Show]] in March 2018, then became the first flying car in production, and was set to launch in 2020,<ref>{{Cite web|url=https://www.scmp.com/magazines/style/tech-design/article/2156412/worlds-first-flying-car-two-seater-pal-v-liberty-track|title=World's first flying car on track for 2020 launch|date=25 July 2018|website=South China Morning Post}}</ref> with full production scheduled for 2021 in [[Gujarat, India]].<ref>{{Cite web|url=https://economictimes.indiatimes.com/industry/auto/auto-news/flying-car-pal-v-to-be-built-in-gujarat-mou-inked-with-dutch-firm/articleshow/74558020.cms|title=Flying car PAL-V to be built in Gujarat, MoU inked with Dutch firm|via=The Economic Times}}</ref> the [[PAL-V ONE]] is a hybrid of a gyrocopter with a leaning 3-wheel motorcycle. It has two seats and a 160 kW flight certified gasoline engine. It has a top speed of {{convert|180|km/h|mi/h|0|abbr=on}} on land and in air, and [[Maximum Takeoff Weight|weighs]] {{convert|910|kg|lb|abbr=on}} max.<ref name=palvGiz>Quick, Darren. [http://www.gizmag.com/pal-v-flying-car/22032/ "PAL-V flying car makes successful first test flight"] ''GizMag'', 2 April 2012. Retrieved 4 April 2012.</ref><ref>{{cite web|url=http://www.pal-v.com/|title=PAL-V |publisher=PAL-V |access-date=2010-10-07}}</ref>\n\nOn April 15, 2021, [[Los Altos, California]], became home to the world's first consumer flying car showroom.<ref>{{Cite web|url=https://www.suasnews.com/2021/04/announcing-aska-the-electric-take-off-and-landing-flying-car-for-consumers/|title=Announcing ASKA\u2122 The Electric Take Off And Landing Flying Car For Consumers|date=15 April 2021}}</ref>"}},
{"article_title": "Film editing", "pageid": "10775", "revid": "1051749197", "timestamp": "2021-10-25T11:26:09Z", "history_paths": [["Film editing --- Introduction ---", "History"]], "categories": ["film editing", "film theory", "film and video technology", "filmmaking", "film production", "cinematic techniques", "articles containing video clips"], "heading_tree": {"Film editing --- Introduction ---": {"History": {"Film editing technology": {}, "Women in film editing": {}}, "Post-production": {}, "Methods of montage": {}, "Continuity editing and alternatives": {}, "Significance": {}, "Assistant editors": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Film editing --- Introduction ---|History": "Early films were short films that were one long, static, and locked-down shot. Motion in the shot was all that was necessary to amuse an audience, so the first films simply showed activity such as traffic moving along a city street. There was no story and no editing. Each film ran as long as there was film in the camera.\n\n[[File:M\u00e9li\u00e8s, Un homme de t\u00eates (Star Film 167 1898).jpg|thumb|250px|Screenshot from ''[[The Four Troublesome Heads]]'', one of the first films to feature [[multiple exposure]]s.]]\n\nThe use of film editing to establish continuity, involving action moving from one sequence into another, is attributed to British film pioneer [[Robert W. Paul]]'s ''[[Come Along, Do!]]'', made in 1898 and one of the first films to feature more than one shot.<ref name="BFIso01">{{cite web |title=Come Along, Do! |first=Michael |last=Brooke |url=http://www.screenonline.org.uk/film/id/444430/ |work=BFI Screenonline Database |access-date=2011-04-24 }}</ref> In the first shot, an elderly couple is outside an [[art exhibition]] having lunch and then follow other people inside through the door. The second shot shows what they do inside. Paul's 'Cinematograph Camera No. 1' of 1896 was the first camera to feature reverse-cranking, which allowed the same film footage to be exposed several times and thereby to create super-positions and [[multiple exposure]]s. One of the first films to use this technique, [[Georges M\u00e9li\u00e8s]]'s ''[[The Four Troublesome Heads]]'' from 1898, was produced with Paul's camera.\n\nThe further development of action continuity in multi-shot films continued in 1899-1900 at the [[Brighton|Brighton School]] in England, where it was definitively established by [[George Albert Smith (film pioneer)|George Albert Smith]] and [[James Williamson (film pioneer)|James Williamson]]. In that year, Smith made ''[[As Seen Through a Telescope]]'', in which the main shot shows street scene with a young man tying the shoelace and then caressing the foot of his girlfriend, while an old man observes this through a telescope. There is then a cut to close shot of the hands on the girl's foot shown inside a black circular mask, and then a cut back to the continuation of the original scene.\n\n[[File:Williamson Fire.ogv|thumb|left|250px|Excerpt from the movie ''Fire!'' directed by [[James Williamson (film pioneer)|James Williamson]]]]\n\nEven more remarkable was [[James Williamson (film pioneer)|James Williamson]]'s ''Attack on a China Mission Station'', made around the same time in 1900. The first shot shows the gate to the mission station from the outside being attacked and broken open by Chinese [[Boxer rebellion|Boxer rebels]], then there is a cut to the garden of the [[Siege of the International Legations|mission station]] where a pitched battle ensues. An armed party of British sailors arrived to defeat the Boxers and rescue the missionary's family. The film used the first "[[reverse angle]]" cut in film history.\n\nJames Williamson concentrated on making films taking action from one place shown in one shot to the next shown in another shot in films like ''Stop Thief!'' and ''Fire!'', made in 1901, and many others. He also experimented with the close-up, and made perhaps the most extreme one of all in ''[[The Big Swallow]]'', when his character approaches the camera and appears to swallow it. These two filmmakers of the Brighton School also pioneered the editing of the film; they tinted their work with color and used trick photography to enhance the narrative. By 1900, their films were extended scenes of up to 5 minutes long.<ref>{{Cite web|url=http://www.bampfa.berkeley.edu/film/FN0552|title=The Brighton School|access-date=2012-12-17|url-status=dead|archive-url=https://web.archive.org/web/20131224113027/http://www.bampfa.berkeley.edu/film/FN0552|archive-date=2013-12-24}}</ref>\n\n[[File:The Great Train Robbery 0018.jpg|thumb|right|250px|Scene from ''[[The Great Train Robbery (1903 film)|The Great Train Robbery]]'' (1903), directed by [[Edwin Stanton Porter]]]]\nOther filmmakers then took up all these ideas including the American [[Edwin Stanton Porter|Edwin S. Porter]], who started making films for the Edison Company in 1901. Porter worked on a number of minor films before making ''[[Life of an American Fireman]]'' in 1903. The film was the first American film with a plot, featuring action, and even a closeup of a hand pulling a fire alarm. The film comprised a continuous narrative over seven scenes, rendered in a total of nine shots.<ref name="musser">Originally in ''Edison Films'' catalog, February 1903, 2\u20133; reproduced in Charles Musser, ''Before the Nickelodeon: Edwin S. Porter and the Edison Manufacturing Company'' (Berkeley: University of California Press, 1991), 216\u201318.</ref> He put a dissolve between every shot, just as [[Georges M\u00e9li\u00e8s]] was already doing, and he frequently had the same action repeated across the dissolves. His film, ''[[The Great Train Robbery (1903 film)|The Great Train Robbery]]'' (1903), had a running time of twelve minutes, with twenty separate shots and ten different indoor and outdoor locations. He used [[cross-cutting]] editing method to show simultaneous action in different places.\n\nThese early film directors discovered important aspects of motion picture language: that the screen image does not need to show a complete person from head to toe and that splicing together two shots creates in the viewer's mind a contextual relationship. These were the key discoveries that made all non-live or non live-on-videotape narrative motion pictures and television possible\u2014that shots (in this case, whole scenes since each shot is a complete scene) can be photographed at widely different locations over a period of time (hours, days or even months) and combined into a narrative whole.<ref>[[Arthur Knight (film critic)|Arthur Knight]] (1957). p. 25.</ref> That is, ''[[The Great Train Robbery (1903 film)|The Great Train Robbery]]'' contains scenes shot on sets of a telegraph station, a railroad car interior, and a dance hall, with outdoor scenes at a railroad water tower, on the train itself, at a point along the track, and in the woods. But when the robbers leave the telegraph station interior (set) and emerge at the water tower, the audience believes they went immediately from one to the other. Or that when they climb on the train in one shot and enter the baggage car (a set) in the next, the audience believes they are on the same train.\n\nSometime around 1918, [[Russians|Russian]] director [[Lev Kuleshov]] did an experiment that proves this point. (See [[Kuleshov Experiment]]) He took an old film clip of a headshot of a noted Russian actor and intercut the shot with a shot of a bowl of soup, then with a child playing with a teddy bear, then with a shot an elderly woman in a casket. When he showed the film to people they praised the actor's acting\u2014the hunger in his face when he saw the soup, the delight in the child, and the grief when looking at the dead woman.<ref>[[Arthur Knight (film critic)|Arthur Knight]] (1957). pp. 72\u201373.</ref> Of course, the shot of the actor was years before the other shots and he never "saw" any of the items. The simple act of juxtaposing the shots in a sequence made the relationship.\n\n[[Image:FirstMoviola.jpg|thumb|237px|The original editing machine: an upright [[Moviola]].]]\n\n Before the widespread use of digital [[non-linear editing system]]s, the initial editing of all films was done with a positive copy of the film negative called a film [[workprint]] (cutting copy in UK) by physically cutting and splicing together pieces of film.<ref>{{Cite web|url=http://www.adapttvhistory.org.uk/stories/objects/cutting-room-practice-and-procedure/|title=Cutting Room Practice and Procedure (BBC Film Training Text no. 58) \u2013 How television used to be made|language=en-US|access-date=2019-02-08}}</ref> Strips of footage would be hand cut and attached together with tape and then later in time, glue. Editors were very precise; if they made a wrong cut or needed a fresh positive print, it cost the production money and time for the lab to reprint the footage. Additionally, each reprint put the negative at risk of damage. With the invention of a splicer and threading the machine with a viewer such as a [[Moviola]], or [[Flatbed editor|"flatbed" machine]] such as a K.-E.-M. or [[Steenbeck]], the editing process sped up a little bit and cuts came out cleaner and more precise. The Moviola editing practice is non-linear, allowing the editor to make choices faster, a great advantage to editing episodic films for television which have very short timelines to complete the work. All film studios and production companies who produced films for television provided this tool for their editors. Flatbed editing machines were used for playback and refinement of cuts, particularly in feature films and films made for television because they were less noisy and cleaner to work with.  \nThey were used extensively for documentary and drama production within the BBC's Film Department. Operated by a team of two, an editor and assistant editor, this tactile process required significant skill but allowed for editors to work extremely efficiently.<ref>Ellis, John; Hall, Nick (2017): ADAPT. figshare. Collection.https://doi.org/10.17637/rh.c.3925603.v1</ref>\n\n[[File:16mm editing synchroniser 1980's 1.jpg|thumbnail|Acmade Picsynch for sound and picture coordination]]\nToday, most films are edited digitally (on systems such as [[Media Composer]], [[Final Cut Pro X]] or [[Premiere Pro]]) and bypass the film positive workprint altogether. In the past, the use of a film positive (not the original negative) allowed the editor to do as much experimenting as he or she wished, without the risk of damaging the original. With digital editing, editors can experiment just as much as before except with the footage completely transferred to a computer hard drive.\n\nWhen the film workprint had been cut to a satisfactory state, it was then used to make an edit decision list (EDL). The negative cutter referred to this list while processing the negative, splitting the shots into rolls, which were then contact printed to produce the final film print or [[answer print]]. Today, production companies have the option of bypassing negative cutting altogether. With the advent of digital intermediate ("DI"), the physical negative does not necessarily need to be physically cut and hot spliced together; rather the negative is optically scanned into the computer(s) and a cut list is confirmed by a DI editor.\n\n In the early years of film, editing was considered a technical job; editors were expected to "cut out the bad bits" and string the film together. Indeed, when the [[Motion Picture Editors Guild]] was formed, they chose to be "below the line", that is, not a creative guild, but a technical one. Women were not usually able to break into the "creative" positions; directors, cinematographers, producers, and executives were almost always men. Editing afforded creative women a place to assert their mark on the filmmaking process. The [[history of film]] has included many women editors such as [[Dede Allen]], [[Anne Bauchens]], [[Margaret Booth]], [[Barbara McLean]], [[Anne V. Coates]], [[Adrienne Fazan]], [[Verna Fields]], [[Blanche Sewell]] and [[Eda Warren]].<ref>{{Cite web|url=https://via.hypothes.is/http://critics-associated.com/a-tedious-job-women-and-film-editing/|title="A Tedious Job" \u2013 Women and Film Editing|last=Galv\u00e3o|first=Sara|date=March 15, 2015|website=Critics Associated via.hypothes.is|language=en-US|access-date=2018-01-15}}</ref>"}},
{"article_title": "Francium", "pageid": "10821", "revid": "1061281807", "timestamp": "2021-12-20T20:00:36Z", "history_paths": [["Francium --- Introduction ---", "History"]], "categories": ["francium", "chemical elements", "alkali metals", "eponyms", "science and technology in france", "chemical elements with body-centered cubic structure"], "heading_tree": {"Francium --- Introduction ---": {"Characteristics": {}, "Isotopes": {}, "Applications": {}, "History": {"Erroneous and incomplete discoveries": {}, "Perey's analysis": {}}, "Occurrence": {}, "Production": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Francium --- Introduction ---|History": "As early as 1870, chemists thought that there should be an alkali metal beyond [[caesium]], with an atomic number of 87.<ref name="andyscouse" /> It was then referred to by the provisional name ''[[Mendeleev's predicted elements|eka-caesium]]''.<ref name="chemeducator">\nAdloff, Jean-Pierre; Kaufman, George B. (September 25, 2005). [http://chemeducator.org/sbibs/s0010005/spapers/1050387gk.htm Francium (Atomic Number 87), the Last Discovered Natural Element] {{Webarchive|url=https://web.archive.org/web/20130604212956/http://chemeducator.org/sbibs/s0010005/spapers/1050387gk.htm |date=June 4, 2013 }} . ''The Chemical Educator'' '''10''' (5). Retrieved on 2007-03-26.\n</ref> Research teams attempted to locate and isolate this missing element, and at least four false claims were made that the element had been found before an authentic discovery was made.\n\n Soviet chemist [[Dmitry Dobroserdov]] was the first scientist to claim to have found eka-caesium, or francium. In 1925, he observed weak radioactivity in a sample of [[potassium]], another alkali metal, and incorrectly concluded that eka-caesium was contaminating the sample (the radioactivity from the sample was from the naturally occurring potassium radioisotope, [[potassium-40]]).<ref name="fontani">{{cite conference| first = Marco| last = Fontani |author-link= Marco Fontani | title = The Twilight of the Naturally-Occurring Elements: Moldavium (Ml), Sequanium (Sq) and Dor (Do)| book-title = International Conference on the History of Chemistry| pages = 1\u20138| date = September 10, 2005| location = Lisbon|url = http://5ichc-portugal.ulusofona.pt/uploads/PaperLong-MarcoFontani.doc| archive-url = https://web.archive.org/web/20060224090117/http://5ichc-portugal.ulusofona.pt/uploads/PaperLong-MarcoFontani.doc|archive-date=February 24, 2006|access-date = April 8, 2007}}</ref> He then published a thesis on his predictions of the properties of eka-caesium, in which he named the element ''russium'' after his home country.<ref name="vanderkroft">{{cite web| last = Van der Krogt| first = Peter| title = Francium| work = Elementymology & Elements Multidict| date = January 10, 2006| url = http://elements.vanderkrogt.net/element.php?sym=Fr| access-date = April 8, 2007}}</ref> Shortly thereafter, Dobroserdov began to focus on his teaching career at the Polytechnic Institute of [[Odessa]], and he did not pursue the element further.<ref name="fontani" />\n\nThe following year, English chemists [[Gerald J. F. Druce]] and [[Frederick H. Loring]] analyzed [[X-ray]] photographs of [[manganese(II) sulfate]].<ref name="vanderkroft" /> They observed spectral lines which they presumed to be of eka-caesium. They announced their discovery of element 87 and proposed the name ''alkalinium'', as it would be the heaviest alkali metal.<ref name="fontani" />\n\nIn 1930, [[Fred Allison]] of the [[Alabama Polytechnic Institute]] claimed to have discovered element 87 (in addition to 85) when analyzing [[pollucite]] and [[lepidolite]] using his [[magneto-optic effect|magneto-optical]] machine. Allison requested that it be named ''virginium'' after his home state of [[Virginia]], along with the symbols Vi and Vm<!--along with them how? and proposed the symbols Vi and Vm?-->.<ref name="vanderkroft" /><ref>{{cite magazine| title = Alabamine & Virginium| magazine = TIME| date = February 15, 1932|url = http://www.time.com/time/magazine/article/0,9171,743159,00.html|archive-url = https://web.archive.org/web/20070930015028/http://www.time.com/time/magazine/article/0,9171,743159,00.html|url-status = dead|archive-date = September 30, 2007| access-date = April 1, 2007}}</ref> In 1934, H.G. MacPherson of [[University of California, Berkeley|UC Berkeley]] disproved the effectiveness of Allison's device and the validity of his discovery.<ref>{{cite journal| last = MacPherson| first = H. G.| title = An Investigation of the Magneto-Optic Method of Chemical Analysis| journal = Physical Review| volume = 47| issue = 4| pages = 310\u2013315|date=1934|doi = 10.1103/PhysRev.47.310|bibcode = 1935PhRv...47..310M }}</ref>\n\nIn 1936, Romanian physicist [[Horia Hulubei]] and his French colleague [[Yvette Cauchois]] also analyzed pollucite, this time using their high-resolution X-ray apparatus.<ref name="fontani" /> They observed several weak emission lines, which they presumed to be those of element 87. Hulubei and Cauchois reported their discovery and proposed the name ''moldavium'', along with the symbol Ml, after [[Moldavia]], the Romanian province where Hulubei was born.<ref name="vanderkroft" /> In 1937, Hulubei's work was criticized by American physicist [[F. H. Hirsh Jr.]], who rejected Hulubei's research methods. Hirsh was certain that eka-caesium would not be found in nature, and that Hulubei had instead observed [[mercury (element)|mercury]] or [[bismuth]] X-ray lines. Hulubei insisted that his X-ray apparatus and methods were too accurate to make such a mistake. Because of this, [[Jean Baptiste Perrin]], [[Nobel Prize]] winner and Hulubei's mentor, endorsed moldavium as the true eka-caesium over [[Marguerite Perey]]'s recently discovered francium. Perey took pains to be accurate and detailed in her criticism of Hulubei's work, and finally she was credited as the sole discoverer of element 87.<ref name="fontani" /> All other previous purported discoveries of element 87 were ruled out due to francium's very limited half-life.<ref name="vanderkroft" />\n\n Eka-caesium was discovered on 7 January 1939 by [[Marguerite Perey]] of the [[Curie Institute (Paris)|Curie Institute]] in Paris,<ref>{{cite journal |doi=10.1333/s00897050956a |url=http://www.perey.org/genealogy/MP%202.pdf |title=Francium (Atomic Number 87), the Last Discovered Natural Element |first1=Jean-Pierre |last1=Adloff |first2=George B. |last2=Kauffman |journal=The Chemical Educator |year=2005 |volume=10 |issue=5 |pages=387\u2013394}}</ref> when she purified a sample of [[actinium]]-227 which had been reported to have a decay energy of 220 keV. Perey noticed decay particles with an energy level below 80 keV. Perey thought this decay activity might have been caused by a previously unidentified decay product, one which was separated during purification, but emerged again out of the pure actinium-227. Various tests eliminated the possibility of the unknown element being [[thorium]], radium, [[lead]], bismuth, or [[thallium]]. The new product exhibited chemical properties of an alkali metal (such as coprecipitating with caesium salts), which led Perey to believe that it was element 87, produced by the [[alpha decay]] of actinium-227.<ref name="chemeducator" /> Perey then attempted to determine the proportion of [[beta decay]] to alpha decay in actinium-227. Her first test put the alpha branching at 0.6%, a figure which she later revised to 1%.<ref name="mcgraw" />\n\nPerey named the new isotope ''actinium-K'' (it is now referred to as francium-223)<ref name="chemeducator" /> and in 1946, she proposed the name ''catium'' (Cm) for her newly discovered element, as she believed it to be the most [[electronegativity|electropositive]] [[cation]] of the elements. [[Ir\u00e8ne Joliot-Curie]], one of Perey's supervisors, opposed the name due to its connotation of ''cat'' rather than ''cation''; furthermore, the symbol coincided with that which had since been assigned to [[curium]].<ref name="chemeducator" /> Perey then suggested ''francium'', after France. This name was officially adopted by the [[International Union of Pure and Applied Chemistry]] (IUPAC) in 1949,<ref name="andyscouse" /> becoming the second element after [[gallium]] to be named after France. It was assigned the symbol Fa, but this abbreviation was revised to the current Fr shortly thereafter.<ref name="hackh">{{Cite book| last = Grant| first = Julius| contribution = Francium| date = 1969| title = Hackh's Chemical Dictionary| pages = 279\u2013280| publisher = McGraw-Hill| isbn = 978-0-07-024067-4}}</ref> Francium was the last element discovered in nature, rather than synthesized, following [[hafnium]] and [[rhenium]].<ref name="chemeducator" /> Further research into francium's structure was carried out by, among others, [[Sylvain Lieberman]] and his team at [[CERN]] in the 1970s and 1980s.<ref>{{cite web\n |title       = History\n |work        = Francium\n |publisher   = [[State University of New York at Stony Brook]]\n |date        = February 20, 2007\n |url         = http://fr.physics.sunysb.edu/francium_news/history.HTM\n |access-date  = March 26, 2007\n |url-status     = dead\n |archive-url  = https://archive.today/19990203121919/http://fr.physics.sunysb.edu/francium_news/history.HTM\n |archive-date = February 3, 1999\n |df          = mdy-all\n}}</ref>"}},
{"article_title": "Floppy disk", "pageid": "10891", "revid": "1062865677", "timestamp": "2021-12-30T23:26:07Z", "history_paths": [["Floppy disk --- Introduction ---", "History"]], "categories": ["1971 in computing", "1971 in technology", "american inventions", "computer-related introductions in 1971", "computer storage media", "floppy disk computer storage", "legacy hardware", "rotating disc computer storage media", "20th-century inventions"], "heading_tree": {"Floppy disk --- Introduction ---": {"History": {"Prevalence": {}, "Gradual transition to other formats": {}, "Use in the early 21st century": {}, "Legacy": {}}, "Design": {"Structure": {"8-inch and 5\u00bc-inch disks": {}, "3\u00bd-inch disk": {}}, "Operation": {"Formatting": {}, "Insertion and ejection": {}, "Finding track zero": {}, "Finding sectors": {}}}, "Sizes": {"{{anchor|8.0}}8-inch floppy disk": {}, "{{anchor|5.25|5.25-inch floppy disk}}5\u00bc-inch floppy disk": {}, "{{anchor|3.5|3.5-inch floppy disk|microfloppy}}3\u00bd-inch floppy disk": {}, "Other sizes": {}, "Sizes, performance and capacity": {}}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Floppy disk --- Introduction ---|History": "[[File:Floppy Disk Drive 8 inch.jpg|left|thumb|8-inch floppy disk,<br /> inserted in drive,<br />(3\u00bd-inch floppy diskette,<br /> in front, shown for scale)]]\n[[File:Floppy disc.jpg|thumb|3\u00bd-inch, high-density floppy diskettes with adhesive labels affixed]]\n{{Main|History of the floppy disk}}\n{{Memory types}}\n\nThe first commercial floppy disks, developed in the late 1960s, were {{convert|8|in|mm|1}} in diameter;<ref name="Teja_1985"/><ref name="Fletcher"/> they became commercially available in 1971 as a component of IBM products and then were sold separately starting in 1972 by [[Memorex]] and others.<ref>{{cite web |url=http://www.computerhistory.org/storageengine/floppy-disk-loads-mainframe-computer-data |title=1971: Floppy disk loads mainframe computer data |website=Computer History Museum |publisher=Computer History Museum |access-date=2015-12-01 |archive-url=https://web.archive.org/web/20151208080520/http://www.computerhistory.org/storageengine/floppy-disk-loads-mainframe-computer-data |archive-date=2015-12-08 |url-status=live}}</ref> These disks and associated drives were produced and improved upon by [[IBM]] and other companies such as Memorex, [[Shugart Associates]], and [[Burroughs Corporation]].<ref>{{cite web |url=http://www.disktrend.com/5decades2.htm |title=Five decades of disk drive industry firsts |access-date=2012-10-15 |url-status=dead |archive-url=https://web.archive.org/web/20110726102519/http://www.disktrend.com/5decades2.htm |archive-date=2011-07-26}}</ref> The term "floppy disk" appeared in print as early as 1970,<ref>IBM's 370/145 Uncovered; Interesting Curves Revealed, Datamation, November 1, 1970</ref> and although IBM announced its first media as the ''Type 1 Diskette'' in 1973, the industry continued to use the terms "floppy disk" or "floppy".\n\nIn 1976, Shugart Associates introduced the 5\u00bc-inch FDD. By 1978, there were more than ten manufacturers producing such FDDs.<ref>{{cite magazine |last=Watson |date=2010-05-24 |title=The Floppy Disk |magazine=[[Canadian Business]] |volume=83 |issue=8 |page=17}}</ref> There were competing [[floppy disk format]]s, with hard- and soft-sector versions and encoding schemes such as [[differential Manchester encoding]] (DM), [[modified frequency modulation]] (MFM), [[Modified frequency modulation#MMFM|M<sup>2</sup>FM]] and [[group coded recording]] (GCR). The 5\u00bc-inch format displaced the 8-inch one for most uses, and the hard-sectored disk format disappeared. The most common capacity of the 5\u00bc-inch format in DOS-based PCs was 360 KB, for the Double-Sided Double-Density (DSDD) format using MFM encoding. In 1984, IBM introduced with its PC-AT model the 1.2 MB dual-sided 5\u00bc-inch floppy disk, but it never became very popular. IBM started using the 720 KB [[double density]] 3\u00bd-inch microfloppy disk on its [[IBM PC Convertible|Convertible]] laptop computer in 1986 and the 1.44 MB [[High-density storage media|high-density]] version with the [[IBM Personal System/2]] (PS/2) line in 1987. These disk drives could be added to older PC models. In 1988, IBM introduced a drive for 2.88 MB Double-Sided Extended-Density (DSED) diskettes in its top-of-the-line PS/2 models, but this was a commercial failure.\n\nThroughout the early 1980s, limits of the 5\u00bc-inch format became clear. Originally designed to be more practical than the 8-inch format, it was becoming considered too large; as the quality of recording media grew, data could be stored in a smaller area.<ref name="Jarrett">"The Microfloppy\u2014One Key to Portability", Thomas R. Jarrett, Computer Technology Review, winter 1983 (Jan 1984), pp. 245\u20137</ref> Several solutions were developed, with drives at 2-, 2\u00bd-, 3-, 3\u00bc-,<ref>[http://www.retrotechnology.com/herbs_stuff/325_inch.jpg Picture of disk]<!-- https://web.archive.org/web/20170619124207/http://www.retrotechnology.com/herbs_stuff/325_inch.jpg --></ref> 3\u00bd- and 4-inches (and [[Sony]]'s {{convert|90|x|94|mm|in|2|abbr=on}} disk) offered by various companies.<ref name="Jarrett"/> They all had several advantages over the old format, including a rigid case with a sliding metal (or later, sometimes plastic) shutter over the head slot, which helped protect the delicate magnetic medium from dust and damage, and a sliding [[write protection]] tab, which was far more convenient than the adhesive tabs used with earlier disks. The large market share of the well-established 5\u00bc-inch format made it difficult for these diverse mutually-incompatible new formats to gain significant market share.<ref name="Jarrett"/> A variant on the Sony design, introduced in 1982 by many manufacturers, was then rapidly adopted. By 1988, the 3\u00bd-inch was outselling the 5\u00bc-inch.<ref>1991 Disk/Trend Report, Flexible Disk Drives, Figure 2</ref>\n\nGenerally, the term floppy disk persisted,<ref group="nb" name="NB_SA"/> even though later style floppy disks have a rigid case around an internal floppy disk.\n\nBy the end of the 1980s, 5\u00bc-inch disks had been superseded by 3\u00bd-inch disks. During this time, PCs frequently came equipped with drives of both sizes. By the mid-1990s, 5\u00bc-inch drives had virtually disappeared, as the 3\u00bd-inch disk became the predominant floppy disk. The advantages of the 3\u00bd-inch disk were its higher capacity, its smaller physical size, and its rigid case which provided better protection from dirt and other environmental risks. If a person touches the exposed disk surface of a 5\u00bc-inch disk through the drive hole, fingerprints may foul the disk—and later the disk drive head if the disk is subsequently loaded into a drive—and it is also easily possible to damage a disk of this type by folding or creasing it, usually rendering it at least partly unreadable. However, largely due to its simpler construction (with no metal parts) the 5\u00bc-inch disk [[unit price]] was lower throughout its history, usually in the range of a third to a half that of a 3\u00bd-inch disk.{{citation needed|date=October 2012}}\n<!-- Sales of 3\u00bd-inch superseded that of 5\u00bc-inch in 1988 -->\n\n [[File:Imation USB FDD 20060623.jpg|thumb|left|[[Imation]] USB floppy drive, model 01946: an external drive that accepts high-density disks]]\nFloppy disks became commonplace during the 1980s and 1990s in their use with [[personal computer]]s to distribute software, transfer data, and create [[backup]]s. Before hard disks became affordable to the general population,<ref group="nb" name="NB_Costs"/> floppy disks were often used to store a computer's [[operating system]] (OS). Most home computers from that time have an elementary OS and [[BASIC]] stored in [[read-only memory]] (ROM), with the option of loading a more advanced OS from a floppy disk.\n\nBy the early 1990s, the increasing software size meant large packages like [[Microsoft Windows|Windows]] or [[Adobe Photoshop]] required a dozen disks or more. In 1996, there were an estimated five billion standard floppy disks in use.<ref name="businessweek">{{cite magazine |last=Reinhardt |first=Andy |date=1996-08-12 |title=Iomega's Zip drives need a bit more zip |magazine=[[Business Week]] |publisher=[[The McGraw-Hill Companies]] |issue=33 |issn=0007-7135 |url=http://www.businessweek.com/1996/33/b3488114.htm |url-status=dead |archive-url=https://web.archive.org/web/20080706151833/http://www.businessweek.com/1996/33/b3488114.htm |archive-date=2008-07-06}}</ref> Then, distribution of larger packages was gradually replaced by [[CD-ROM]]s, [[DVD]]s, and online distribution.\n\nAn attempt to enhance the existing 3\u00bd-inch designs was the [[SuperDisk]] in the late 1990s, using very narrow data tracks and a high precision head guidance mechanism with a capacity of 120 [[Megabyte|MB]]<ref>{{cite web |url=http://linuxcommand.org/man_pages/floppy8.html |title=floppy |publisher=LinuxCommand.org |date=2006-01-04 |access-date=2011-06-22 |url-status=dead |archive-url=https://web.archive.org/web/20110727034443/http://linuxcommand.org/man_pages/floppy8.html |archive-date=2011-07-27}}</ref> and backward-compatibility with standard 3\u00bd-inch floppies; a [[format war]] briefly occurred between SuperDisk and other high-density floppy-disk products, although ultimately recordable CDs/DVDs, solid-state flash storage, and eventually online storage would render all these removable disk formats obsolete. External [[USB]]-based floppy disk drives are still available, and many modern systems provide firmware support for booting from such drives.\n\n [[File:Disk-cleaning-kit-front-and-rear.jpg|thumb|Front and rear of a retail 3\u00bd-inch and 5\u00bc-inch floppy disk cleaning kit, as sold in Australia at retailer Big W, circa early 1990s]]\nIn the mid-1990s, mechanically incompatible higher-density floppy disks were introduced, like the [[Zip drive|Iomega Zip disk]]. Adoption was limited by the competition between proprietary formats and the need to buy expensive drives for computers where the disks would be used. In some cases, failure in market penetration was exacerbated by the release of higher-capacity versions of the drive and media being not [[backward compatibility|backward-compatible]] with the original drives, dividing the users between new and old adopters. Consumers were wary of making costly investments into unproven and rapidly changing technologies, so none of the technologies became the established standard.\n\nApple introduced the [[iMac G3]] in 1998 with a CD-ROM drive but no floppy drive; this made USB-connected floppy drives popular accessories, as the iMac came without any writable removable media device.\n\n[[CD-R|Recordable CDs]] were touted as an alternative, because of the greater capacity, compatibility with existing CD-ROM drives, and\u2014with the advent of [[CD-RW|re-writeable CD]]s and packet writing\u2014a similar reusability as floppy disks.\nHowever, CD-R/RWs remained mostly an archival medium, not a medium for exchanging data or editing files on the medium itself, because there was no common standard for packet writing which allowed for small updates.\nOther formats, such as [[Magneto-optical drive|Magneto-optical discs]], had the flexibility of floppy disks combined with greater capacity, but remained niche due to costs.\nHigh-capacity backward compatible floppy technologies became popular for a while and were sold as an option or even included in standard PCs, but in the long run, their use was limited to professionals and enthusiasts.\n\nFlash-based USB-thumb drives finally were a practical and popular replacement, that supported traditional file systems and all common usage scenarios of floppy disks. As opposed to other solutions, no new drive type or special software was required that impeded adoption, since all that was necessary was an already common [[USB]] port.\n\n[[File:Different types of storage components.jpg|thumb|Different data storage media (Examples include: [[Flash drive]],  [[Cd|CD]], [[Tape drive]], and  [[CompactFlash]])]]\n\n [[File:Floppy hardware emulator.jpg|thumb|left|A [[Floppy disk hardware emulator|floppy hardware emulator]], same size as a 3\u00bd-inch drive, provides a USB interface to the user]]By 2002, most manufacturers still provided floppy disk drives as standard equipment to meet user demand for [[Sneakernet|file-transfer]] and an emergency boot device, as well as for the general secure feeling of having the familiar device.<ref>{{cite magazine |last=Spring |first=Tom |date=2002-07-24 |title=What Has Your Floppy Drive Done for You Lately? PC makers are still standing by floppy drives despite vanishing consumer demand |url=http://www.pcworld.com/article/103037/what_has_your_floppy_drive_done_for_you_lately.html |magazine=[[PC World]] |access-date=2012-04-04 |url-status=dead |archive-url=https://web.archive.org/web/20111224033044/http://www.pcworld.com/article/103037/what_has_your_floppy_drive_done_for_you_lately.html |archive-date=2011-12-24}}</ref> By this time, the retail cost of a floppy drive had fallen to around $20 ({{Inflation|US|20|2002|fmt=eq}}), so there was little financial incentive to omit the device from a system. Subsequently, enabled by the widespread support for USB flash drives and BIOS boot, manufacturers and retailers progressively reduced the availability of floppy disk drives as standard equipment. In February 2003, [[Dell]], a leading computer company at the time, announced that floppy drives would no longer be pre-installed on [[Dell Dimension]] home computers, although they were still available as a selectable option and purchasable as an aftermarket [[Original equipment manufacturer|OEM]] add-on.<ref>{{cite web |url=http://news.bbc.co.uk/1/hi/uk/2905953.stm |title=R.I.P. Floppy Disk |work=[[BBC News]] |date=2003-04-01 |access-date=2011-07-19 |archive-url=https://web.archive.org/web/20090216235741/http://news.bbc.co.uk/1/hi/uk/2905953.stm |archive-date=2009-02-16 |url-status=live}}</ref> By January 2007, only 2% of computers sold in stores contained built-in floppy disk drives.<ref name="PCW">{{cite news |last=Derbyshire |first=David |url=https://www.telegraph.co.uk/news/uknews/1540984/Floppy-disks-ejected-as-demand-slumps.html |title=Floppy disks ejected as demand slumps |publisher=[[The Daily Telegraph]] |date=2007-01-30 |access-date=2011-07-19 |archive-url=https://web.archive.org/web/20110522070711/http://www.telegraph.co.uk/news/uknews/1540984/Floppy-disks-ejected-as-demand-slumps.html |archive-date=2011-05-22 |url-status=live}}</ref>\n\nFloppy disks are used for emergency boots in aging systems lacking support for other [[boot disk|bootable media]] and for [[BIOS]] updates, since most BIOS and [[firmware]] programs can still be executed from [[Boot disk#Boot floppies|bootable floppy disks]]. If BIOS updates fail or become corrupt, floppy drives can sometimes be used to perform a recovery. The music and theatre industries still use equipment requiring standard floppy disks (e.g. synthesizers, samplers, drum machines, sequencers, and [[lighting control console|lighting consoles]]). Industrial automation equipment such as programmable [[Machine industry|machinery]] and [[industrial robot]]s may not have a USB interface; data and programs are then loaded from disks, damageable in industrial environments. This equipment may not be replaced due to cost or requirement for continuous availability; existing software emulation and [[virtualization]] do not solve this problem because a customized operating system is used that has no [[device driver|drivers]] for USB devices. [[Floppy disk hardware emulator|Hardware floppy disk emulators]] can be made to interface [[floppy-disk controller]]s to a USB port that can be used for flash drives.\n\nIn May 2016, the United States [[Government Accountability Office]] released a report that covered the need to upgrade or replace legacy computer systems within federal agencies. According to this document, old [[IBM Series/1]] minicomputers running on [[#8.0|8-inch floppy disk]]s are still [[nuclear command and control|used to coordinate]] "the operational functions of the United States' nuclear forces". The government planned to update some of the technology by the end of the 2017 fiscal year.<ref name=":0">{{Cite web |url=http://www.gao.gov/assets/680/677436.pdf |title=Federal Agencies Need to Address Aging Legacy Systems |date=May 2016 |website=Report to Congressional Requesters |publisher=United States Government Accountability Office |access-date=2016-05-26 |archive-url=https://web.archive.org/web/20160602113649/http://www.gao.gov/assets/680/677436.pdf |archive-date=2016-06-02 |url-status=live}}</ref><ref name="thehill-20160525">{{cite news |first=Mario |last=Trujillo |work=The Hill |date=2016-05-25 |url=http://thehill.com/policy/technology/281191-us-nuclear-emergency-messaging-system-still-uses-floppy-disks |title=US nuclear emergency messaging system still uses floppy disks |access-date=2016-05-30 |url-status=live |archive-url=https://web.archive.org/web/20160529100524/http://thehill.com/policy/technology/281191-us-nuclear-emergency-messaging-system-still-uses-floppy-disks |archive-date=2016-05-29}}</ref>\n\nExternal USB floppy drives function as a [[USB mass storage device class]]. Windows 10 removed the driver for internal floppy drives, which are a different device. External USB floppy drives continue to function.<ref>{{Cite web |url=https://www.thewindowsclub.com/use-floppy-disk-windows-10 |title=How to use Floppy Disk on Windows 10 |date=2016-03-09 |access-date=2019-06-11 |url-status=live |archive-url=https://web.archive.org/web/20181117134806/https://www.thewindowsclub.com/use-floppy-disk-windows-10 |archive-date=2018-11-17}}</ref>\n\nThe [[British Airways]] [[Boeing 747-400]] fleet, up to its retirement in 2020, used 3.5-inch floppy disks to load avionics software.<ref>{{cite news |last=Warren |first=Tom |date=August 11, 2020 |title=Boeing 747s still get critical updates via floppy disks: A rare look inside a 20-year-old airliner |url=https://www.theverge.com/2020/8/11/21363122/boeing-747s-floppy-disc-updates-critical-software |website=[[The Verge]] |publisher=Vox Media |access-date=2021-02-26}}</ref>\n\n [[File:Save Icon in Open Office.png|thumb|right|Screenshot depicting a floppy disk as "save" icon]]\nFor more than two decades, the floppy disk was the primary external writable storage device used. Most computing environments before the 1990s were non-networked, and floppy disks were the primary means to transfer data between computers, a method known informally as [[sneakernet]]. Unlike hard disks, floppy disks are handled and seen; even a novice user can identify a floppy disk. Because of these factors, a picture of a 3\u00bd-inch floppy disk became an [[interface metaphor]] for saving data. The floppy disk symbol is still used by software on user-interface elements related to saving files, such as the release of [[Microsoft Office 2019]], even though the physical floppy disks are largely obsolete, making it a [[skeuomorph]].<ref name="Landphair">{{cite news|last=Landphair|first=Ted|date=2007-03-10|title=So Long, Faithful Floppies|work=VOA News|publisher=Voice of America|url=http://www.voanews.com/content/a-13-2007-03-10-voa3-66771407/564323.html|url-status=dead|access-date=2008-12-25|archive-url=https://web.archive.org/web/20161010215401/http://www.voanews.com/a/a-13-2007-03-10-voa3-66771407/564323.html|archive-date=October 10, 2016}}</ref>"}},
{"article_title": "Film stock", "pageid": "11028", "revid": "1043890041", "timestamp": "2021-09-12T14:29:00Z", "history_paths": [["Film stock --- Introduction ---", "History"]], "categories": ["audiovisual introductions in 1889", "film and video technology", "storage media"], "heading_tree": {"Film stock --- Introduction ---": {"History": {"1888\u20131899: Before standardization": {}, "1900\u20131919: Toward the standard picture film": {}, "1920s: Diversification of film sensitivity": {}, "Colour films": {}}, "Classification and properties": {"Base": {}, "Emulsion": {}, "Chemistry": {}, "Image record": {}, "Physical characteristics": {}, "Responsivity": {}, "Colour temperature": {}}, "Deterioration": {}, "Intermediate and print stocks": {}, "Decline": {}, "See also": {}, "References": {"Bibliography": {}, "Further reading": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Film stock --- Introduction ---|History": "Early motion picture experiments in the 1880s were performed using a fragile [[paper]] roll film, with which it was difficult to view a single, continuously moving image without a complex apparatus. The first transparent and flexible [[film base]] material was [[celluloid]], which was discovered and refined for photographic use by [[John Carbutt]], [[Hannibal Goodwin]], and [[George Eastman]].<ref name="kodak.com">{{cite web |url=http://www.kodak.com/ek/US/en/Our_Company/History_of_Kodak/Milestones_-_chronology/1878-1929.htm |title=1878-1929 |website=www.kodak.com |access-date=8 August 2015 |url-status=dead |archive-url=https://web.archive.org/web/20150823030506/http://www.kodak.com/ek/US/en/Our_Company/History_of_Kodak/Milestones_-_chronology/1878-1929.htm |archive-date=23 August 2015 }}</ref> [[Eastman Kodak]] made celluloid film commercially available in 1889; [[Thomas Henry Blair]], in 1891, was his first competitor. The stock had a frosted base to facilitate easier viewing by transmitted light. Emulsions were [[orthochromatic]]. By November 1891 [[William Kennedy Dickson|William Dickson]], at [[Thomas Edison|Edison]]'s laboratory, was using Blair's stock for [[Kinetoscope]] experiments.<ref name="kodak.com"/> Blair's company supplied film to Edison for five years. Between 1892 and 1893, Eastman experienced problems with production. Because of patent lawsuits in 1893, Blair left his American company and established another in Britain. Eastman became Edison's supplier of film.\n\nBlair's new company supplied European filmmaking pioneers, including [[Birt Acres]], [[Robert W. Paul|Robert Paul]], [[George Albert Smith (film pioneer)|George Albert Smith]], [[Charles Urban]], and the [[Lumi\u00e8re Brothers]]. By 1896, the new [[movie projector]] required a fully transparent film base that Blair's American operation could not supply. Eastman shortly thereafter bought the company out and became the leading supplier of film stock. [[Louis Lumi\u00e8re]] worked with [[Victor Planchon]] to adapt the Lumi\u00e8re "Blue Label" (Etiquette Bleue) photographic plate emulsion for use on celluloid roll film, which began in early 1896.\n\nEastman's first motion picture film stock was offered in 1889.<ref name="aipcinema.com">{{Cite web|url=http://www.aipcinema.com/ficheiros/Conteudos/KODAK_FILM_HISTORY.pdf|title=KODAK FILM HISTORY Chronology of Motion Picture Films - 1889 to 1939|url-status=dead|archive-url=https://web.archive.org/web/20130515033307/http://www.aipcinema.com/ficheiros/Conteudos/KODAK_FILM_HISTORY.pdf|archive-date=15 May 2013|access-date=2 February 2013}}</ref> At first the film was the same as photographic film. By 1916, separate "Cine Type" films were offered.<ref name="aipcinema.com"/> From 1895, Eastman supplied their motion picture roll film in rolls of 65 feet, while Blair's rolls were 75 feet. If longer lengths were needed, the unexposed negative rolls could be cemented in a [[darkroom]], but this was largely undesirable by most narrative filmmakers. The makers of [[Actuality film]]s were much more eager to undertake this method, however, in order to depict longer actions. They created cemented rolls as long as 1,000 feet. [[American Mutoscope and Biograph]] was the first known company to use such film for the [[James J. Jeffries|Jeffries]]-[[Tom Sharkey|Sharkey]] fight on 3 November 1899.\n\n As the quantity of film and filmmakers grew, the demand for standardization increased. Between 1900 and 1910, [[list of film formats|film formats]] gradually became [[standardization|standardized]] and film stocks improved. A number of [[film gauge]]s were made. Eastman increased the length of rolls to 200 feet without major adjustments to the emulsion, retaining a large market share. Lumi\u00e8re reformulated its stock to match the speed of Eastman film, naming it 'Etiquette Violette' (Violet Label). Blair sold his English company to [[Path\u00e9]] in 1907 and retired to the US. Path\u00e9 began to supplement its operation in 1910 by purchasing film prints, stripping the emulsion from the film base and re-coating it. [[35 mm movie film|35mm film]] began to become the dominant gauge because of the commonality of Edison's and Lumi\u00e8re's [[cameras]]. Consumers usually purchased unperforated film and had to punch it by perforators that were often imprecise, causing difficulty in making prints for the opposite perforation format. In 1908, the perforators began to be made by [[Bell and Howell]]. Eastman Kodak used the Bell and Howell's machine to perforate its films. In 1909, Edison's organization of the [[Edison Trust|Motion Picture Patents Trust]] agreed to what would become the standard: 35 mm gauge, with Edison perforations and a 1.33 [[aspect ratio (image)|aspect ratio]].<ref>The gauge and perforations are almost identical to modern film stock; the full silent ratio is also used as the [[film gate]] in movie cameras, although portions of the image (excluding those shot with an [[anamorphic]] lens) are later cropped out in post-production and projection.</ref>\n[[Image:16mmBWrevDP.png|thumb|A silent home movie on [[16 mm film|16mm]] [[black-and-white]] reversal double perforation film stock]]\n[[Agfa]] began to produce motion picture film in 1913, but remained a largely local supplier until World War I boycotts of popular French, American and Italian film stocks allowed the [[Universum Film AG|UFA]] film studio to flourish, boosting Agfa's orders. All film stocks were manufactured on a [[Nitrate film|nitrate film base]], which is highly flammable. Nitrate film fires were virtually impossible to extinguish. A significant number of fatal accidents occurred in theatrical projection booths, where the heat of the projector lamp made ignition a possibility. Amateur [[filmmaking]] ([[home movies]]) slowly developed during this period. Kodak developed a heat-resistant 'safety base' for home projection.\n\nIn 1909, tests showed [[cellulose diacetate]] to be a viable replacement base, and Kodak began selling acetate-base films the following year in 22 mm widths for Edison's work on the [[Home Kinetoscope]], which was commercially released in 1912. Eastman Kodak introduced a non-flammable 35 mm film stock in 1909. The [[plasticizer]]s used to make the film flexible evaporated quickly, making the film dry and brittle, causing splices to part and perforations to tear. In 1911 the major American film studios returned to using nitrate stock.<ref>Eileen Bowser, ''The Transformation of Cinema 1907\u20131915'', Charles Scribner's Sons, 1990, p. 74\u201375. {{ISBN|0-684-18414-1}}.</ref> More amateur formats began to use acetate-based film, and several, including Kodak's own [[16 mm]] format, were designed specifically to be manufactured with safety base. Kodak released Cine Negative Film Type E in 1916 and Type F (later known as Negative Film Par Speed Type 1201) in 1917. As both of these orthochromatic films were no faster than previous offerings, the improvements were in granularity and sharpness.\n\n Film stock manufacturers began to diversify their products. Each manufacturer had previously offered one negative stock (usually orthochromatic) and one print stock. In 1920, a variant of Type F film known as X-back was introduced to counteract the effects of static electricity on the film, which can cause [[Electric spark|sparking]] and create odd [[exposure patterns]] on the film. A resin backing was used on the film, which rendered the film too opaque to allow focusing through the back of the film, a common technique for many cameras of that era. The X-back stock was popular on the east coast of the US. Other manufacturers were established in the 1920s, including American [[E.I. Dupont de Nemours]] in 1926 and Belgian [[Agfa-Gevaert|Gevaert]] in 1925. [[Panchromatic]] film stock became more common. Created in 1913 for use in early color film processes such as [[Kinemacolor]], panchromatic was first used in a black-and-white film for exterior sequences in ''[[Queen of the Sea (film)|Queen of the Sea]]'' (1918) and originally available as a special order product.<ref>Koszarski (1994). p. 140.</ref> The stock's increased sensitivity to red light made it an attractive option for [[day for night]] shooting. Kodak financed a feature in 1922, shot entirely with panchromatic stock, ''[[The Headless Horseman (1922 film)|The Headless Horseman]]'', to promote the film when Kodak introduced it as a standard option. Panchromatic film stock increased costs and no motion pictures were produced on it in their entirety for several years. The cross-cutting between panchromatic and orthochromatic stocks caused continuity problems with costume tones and [[panchromatic film]] was often avoided.\n\nOrthochromatic film remained dominant until the mid-1920s due to Kodak's lack of competition in the panchromatic market. In 1925, Gevaert introduced an orthochromatic stock with limited color sensitivity and a fully panchromatic stock, Pan-23. In 1926, Kodak lowered the price of panchromatic stock to parity with its orthochromatic offering and the panchromatic stock began to overtake the orthochromatic stock's market share within a few years.<ref>Salt (1992). p. 179. "There was apparently some question as to differences in relative contrast between the two stocks. As Barry Salt notes, "this claim is almost impossible to substantiate now, given the extreme difficulty there is in seeing a reasonable number of original prints of films shot on both stocks."</ref> As similar panchromatic film stocks were also manufactured by Agfa and Path\u00e9, making the shift to panchromatic stocks largely complete by 1928, Kodak discontinued orthochromatic stock in 1930.<ref>[https://www.kodak.com/US/en/motion/about/chronology_of_film/index.htm# Kodak: Chronology of Motion Picture Films, 1889 to 1939].</ref>\n\n {{further|Colour motion picture film}}\nExperiments with colour films were made as early as the late 19th century, but practical colour film was not commercially viable until 1908, and for amateur use when Kodak introduced [[Kodachrome]] for 16 mm in 1935 and [[8 mm film|8 mm]] in 1936. Commercially successful colour processes used special cameras loaded with black-and-white separation stocks rather than colour negative. [[Kinemacolor]] (1908\u20131914), [[Technicolor]] processes 1 through 4 (1917\u20131954), and [[Cinecolor]] used one, two or three strips of monochrome film stock sensitized to certain primary colours or exposed behind colour filters in special cameras. Technicolor introduced a colour [[reversal film|reversal]] stock, called Monopack, for location shooting in 1941; it was ultimately a 35 mm version of Kodachrome that could be used in standard motion picture cameras.\n\nEastman Kodak introduced their first [[35 mm format|35mm]] colour negative stock, Eastman Colour Negative film 5247, in 1950.<ref name=":0">{{Cite web|url=https://www.kodak.com/gb/en/motion/About/Chronology_Of_Film/1940-1959/default.htm|title=1940 - 1959 {{!}} Motion Picture Film|website=www.kodak.com|access-date=12 December 2019}}</ref> A higher quality version in 1952, Eastman Colour Negative film 5248, was quickly adopted by Hollywood for colour motion picture production, replacing both the expensive three-strip Technicolor process and Monopack.<ref name=":0" />\n<!-- 5247 was not invented in 1950 and 5248 was definitely not invented in 1952.<ref>eastman kodak</ref> -->"}},
{"article_title": "Fuel cell", "pageid": "11729", "revid": "1062835647", "timestamp": "2021-12-30T20:46:37Z", "history_paths": [["Fuel cell --- Introduction ---", "History"]], "categories": ["1838 introductions", "fuel cells", "bright green environmentalism", "energy conversion", "hydrogen economy", "hydrogen technologies", "energy storage"], "heading_tree": {"Fuel cell --- Introduction ---": {"History": {}, "Types of fuel cells; design": {"Proton-exchange membrane fuel cells": {"Proton-exchange membrane fuel cell design issues": {}}, "Phosphoric acid fuel cell": {}, "Solid acid fuel cell": {}, "Alkaline fuel cell": {}, "High-temperature fuel cells": {"Solid oxide fuel cell": {}, "Molten-carbonate fuel cell": {}}, "Electric storage fuel cell": {}, "Comparison of fuel cell types": {}}, "Efficiency of leading fuel cell types": {"Theoretical maximum efficiency": {}, "In practice": {}}, "Applications": {"Power": {}, "Cogeneration": {}, "Fuel cell electric vehicles (FCEVs)": {"Automobiles": {"Criticism": {}}, "Buses": {}, "Trucks": {}, "Forklifts": {}, "Motorcycles and bicycles": {}, "Airplanes": {}, "Boats": {}, "Submarines": {}}, "Portable power systems": {}, "Other applications": {}, "Fueling stations": {}}, "Markets and economics": {}, "Research and development": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Fuel cell --- Introduction ---|History": "{{Main|Timeline of hydrogen technologies}}\n[[File:1839 William Grove Fuel Cell.jpg|thumb|right|Sketch of Sir [[William Robert Grove|William Grove]]'s 1839 fuel cell]]\nThe first references to hydrogen fuel cells appeared in 1838. In a letter dated October 1838 but published in the December 1838 edition of ''The London and Edinburgh Philosophical Magazine and Journal of Science'', Welsh physicist and barrister Sir [[William Robert Grove|William Grove]] wrote about the development of his first crude fuel cells. He used a combination of sheet iron, copper and porcelain plates, and a solution of sulphate of copper and dilute acid.<ref>{{cite journal |title=Mr. W. R. Grove on a new Voltaic Combination |publisher=The London and Edinburgh Philosophical Magazine and Journal of Science | year=1838 |access-date=2 October 2013 |url=https://archive.org/stream/londonedinburghp13lond/londonedinburghp13lond_djvu.txt | doi=10.1080/14786443808649618}}</ref><ref>{{cite journal | last1 = Grove | first1 = William Robert | year = 1839 | title = On Voltaic Series and the Combination of Gases by Platinum | url = https://zenodo.org/record/1431021| journal = Philosophical Magazine and Journal of Science | volume = XIV | issue = 86\u201387| pages = 127\u2013130 | doi=10.1080/14786443908649684}}</ref> In a letter to the same publication written in December 1838 but published in June 1839, German physicist [[Christian Friedrich Sch\u00f6nbein]] discussed the first crude fuel cell that he had invented.  His letter discussed current generated from hydrogen and oxygen dissolved in water.<ref>{{cite web|title=On the Voltaic Polarization of Certain Solid and Fluid Substances |publisher=The London and Edinburgh Philosophical Magazine and Journal of Science |year=1839 |access-date=2 October 2013 |url=http://electrochem.cwru.edu/estir/hist/hist-14-Schoenbein.pdf |url-status=dead |archive-url=https://web.archive.org/web/20131005022402/http://electrochem.cwru.edu/estir/hist/hist-14-Schoenbein.pdf |archive-date= 5 October 2013 }}</ref> Grove later sketched his design, in 1842, in the same journal. The fuel cell he made used similar materials to today's [[phosphoric acid fuel cell]].<ref>{{cite journal | last1 = Grove | first1 = William Robert | year = 1842 | title = On a Gaseous Voltaic Battery | url = https://zenodo.org/record/1431031| journal = Philosophical Magazine and Journal of Science | volume = XXI | issue = 140| pages = 417\u2013420 | doi=10.1080/14786444208621600}}</ref><ref>{{cite book |last1=Larminie |first1=James |last2=Dicks |first2=Andrew |title=Fuel Cell Systems Explained |url=https://87eb298c-a-62cb3a1a-s-sites.googlegroups.com/site/senthilvssc/Home/fuel-cells/FuelCellSystemsExplained_Second.Edition_Wiley2003_.pdf?attachauth=ANoY7crX_IkVIPQ-acr5K0O8seJelGPHSyLjN0WxCGzldpUgBnBfXrPV2bzNvA7s8HDmRMeqPO5Okjy7ysDnw5-lT1tAidw1fwf8LULLQT98hybocX63JkBhjgIEDl_2v-GLGFkD5YebdMUrHjb-IwiM3okL2sGmqOMGQt514PAYjAiktAv1uHuh4izkW4R8-PjEXMD1lKTf1sH76F8Oy44uV1n2J0gDxtwd_HcLZhrzc86kzjcLfygo_hXPDdwCpI3kvb9gI-gPTMRjFTc-6S1upFRfxcBEMIG5Jn4osQqAgzO2BAseRjw%3D&attredirects=0 }}{{Dead link|date=December 2021 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>\n\n{{Quote box|width=26%|align=left|quote=In 1932, Francis Thomas Bacon invented a fuel cell which derived power from hydrogen and oxygen. This was used by NASA to power lights, air-conditioning and communications.| source=The Brits who bolstered the Moon landings, [[BBC Archives]].<ref name="BBC"/>}}\nIn 1932, English engineer [[Francis Thomas Bacon]] successfully developed a 5 kW stationary fuel cell.<ref name="BBC"/> The [[alkaline fuel cell]] (AFC), also known as the Bacon fuel cell after its inventor, is one of the most developed fuel cell technologies, which [[NASA]] has used since the mid-1960s.<ref name="BBC">{{cite news |title=The Brits who bolstered the Moon landings |url=https://www.bbc.co.uk/archive/the-brits-who-bolstered-the-moon-landings/zfcrscw |access-date=7 August 2019 |agency=BBC}}</ref><ref>{{cite news |title=Apollo 11 mission 50 years on: The Cambridge scientist who helped put man on the moon |url=https://www.cambridgeindependent.co.uk/news/apollo-11-mission-50-years-on-the-cambridge-scientist-who-helped-put-man-on-the-moon-9077166/ |access-date=7 August 2019 |work=Cambridge Independent}}</ref>\n\nIn 1955, W. Thomas Grubb, a chemist working for the [[General Electric]] Company (GE), further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane as the electrolyte. Three years later another GE chemist, Leonard Niedrach, devised a way of depositing platinum onto the membrane, which served as catalyst for the necessary hydrogen oxidation and oxygen reduction reactions. This became known as the "Grubb-Niedrach fuel cell".<ref>{{Cite web|url=https://americanhistory.si.edu/fuelcells/pem/pem2.htm|title=Fuel Cell Project: PEM Fuel Cells photo #2|website=americanhistory.si.edu}}</ref><ref>{{Cite web|url=https://americanhistory.si.edu/fuelcells/pem/pemmain.htm|title=Collecting the History of Proton Exchange Membrane Fuel Cells|website=americanhistory.si.edu}}</ref> GE went on to develop this technology with NASA and McDonnell Aircraft, leading to its use during [[Project Gemini]]. This was the first commercial use of a fuel cell. In 1959, a team led by Harry Ihrig built a 15 kW fuel cell tractor for [[Allis-Chalmers]], which was demonstrated across the U.S. at state fairs. This system used potassium hydroxide as the electrolyte and [[compressed hydrogen]] and oxygen as the reactants. Later in 1959, Bacon and his colleagues demonstrated a practical five-kilowatt unit capable of powering a welding machine. In the 1960s, [[Pratt & Whitney]] licensed Bacon's U.S. patents for use in the U.S. space program to supply electricity and drinking water (hydrogen and oxygen being readily available from the spacecraft tanks). In 1991, the first hydrogen fuel cell automobile was developed by [[Roger Billings]].<ref>{{cite web | title = Roger Billings Biography | publisher = International Association for Hydrogen Energy | url = http://www.iahe.org/advisory.asp?did=2 | access-date = 2011-03-08 | archive-date = 24 February 2021 | archive-url = https://web.archive.org/web/20210224145900/http://www.iahe.org/advisory.asp?did=2 | url-status = dead }}</ref><ref>{{cite web | title = Spotlight on Dr. Roger Billings | publisher = Computer Technology Review | url = http://wwpi.com/spotlight-on-dr-roger-billings-science-and-technology-luminary/ | access-date = 2015-09-21 | archive-date = 27 March 2016 | archive-url = https://web.archive.org/web/20160327053930/http://wwpi.com/spotlight-on-dr-roger-billings-science-and-technology-luminary | url-status = dead }}</ref>\n\n[[UTC Power]] was the first company to manufacture and commercialize a large, stationary fuel cell system for use as a [[co-generation]] power plant in hospitals, universities and large office buildings.<ref>{{cite web|title=The PureCell Model 400 \u2013 Product Overview |publisher=UTC Power |url=http://www.utcpower.com/products/purecell400 |access-date=2011-12-22 |url-status=dead |archive-url=https://web.archive.org/web/20111211055124/http://www.utcpower.com/products/purecell400 |archive-date=11 December 2011}}</ref>\n\nIn recognition of the fuel cell industry and America's role in fuel cell development, the US Senate recognized 8 October 2015 as [[National Hydrogen and Fuel Cell Day]], passing S. RES 217. The date was chosen in recognition of the atomic weight of hydrogen (1.008).<ref>{{cite web |url=http://r20.rs6.net/tn.jsp?f=001LqlfeaefMaMk1AcYFGQCVusor-20uN4bi7IpOZRAGd8c2aQviqrojcrnEQs9Qr1O3ieGWFl1xfZHONJLBsX6S9HVo2ecgD_fArmcivCZnzHUCwqVLPgje33ZJtGkTvadenmcAoDf_M1ryFfBtKLDwpzJ-zfyVMf11H40bbKa8EA5uWFsexBYhM0FeOY9ecsxsZUV2bqkJULCmD8bnp1eDI1bO34TGx924WTBTdi4LVgMm0LWfjxERzXbtjCwlOSSDhcyUr_gA-2hEM5aVTjOLnt--lFB-ICS-396bvf2OG0YyNqlaYj9fXJwbRJ0g7khuFCsDIiJ56M0T5Z8McCXxgyxDxP2r_ajDJLL907cOwA=&c=a-wZ-VeAmd_6WqH6NvbmTp4DGWAG1-DMmZ7xZ88XTUfW3137XIzlQg==&ch=Q0EdtWJhosSPKr8NtUOS9eED8QUTbl2Q3MOaaew988Z0dYRbHQKkYg== |title=S.Res.217 \u2013 A resolution designating October 8, 2015, as "National Hydrogen and Fuel Cell Day" |website=Congress.gov |date= 29 September 2015}}</ref>"}},
{"article_title": "Genetic engineering", "pageid": "12383", "revid": "1057572417", "timestamp": "2021-11-28T11:57:09Z", "history_paths": [["Genetic engineering --- Introduction ---", "History"]], "categories": ["genetic engineering", "1950s neologisms", "1972 introductions", "emerging technologies", "biological engineering", "biotechnology", "molecular biology", "engineering disciplines"], "heading_tree": {"Genetic engineering --- Introduction ---": {"Overview": {}, "History": {}, "Process": {"Gene isolation and cloning": {}, "Inserting DNA into the host genome": {}}, "Applications": {"Medicine": {}, "Research": {}, "Industrial": {}, "Agriculture": {}, "Other applications": {}}, "Regulation": {}, "Controversy": {}, "In popular culture": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Genetic engineering --- Introduction ---|History": "{{main|History of genetic engineering}}\n\nHumans have altered the genomes of species for thousands of years through [[selective breeding]], or artificial selection<ref name=Root>{{cite book|title=Domestication|url={{google books |plainurl=y |id=WGDYHvOHwmwC}}|first=Clive |last=Root| name-list-style = vanc |year=2007|publisher=Greenwood Publishing Groups}}</ref>{{rp|1}}<ref name=Zohary>{{cite book |title=Domestication of Plants in the Old World: The origin and spread of plants in the old world|url={{google books |plainurl=y |id=tc6vr0qzk_4C}}|first1=Daniel |last1=Zohary |first2=Maria |last2=Hopf |first3=Ehud |last3=Weiss | name-list-style = vanc |year=2012|publisher=Oxford University Press}}</ref>{{rp|1}} as contrasted with [[natural selection]]. More recently, [[mutation breeding]] has used exposure to chemicals or radiation to produce a high frequency of random mutations, for selective breeding purposes. Genetic engineering as the direct manipulation of DNA by humans outside breeding and mutations has only existed since the 1970s. The term "genetic engineering" was first coined by [[Jack Williamson]] in his [[science fiction]] novel ''Dragon's Island'', published in 1951<ref>{{cite book|last=Stableford|first=Brian M.| name-list-style = vanc |title=Historical dictionary of science fiction literature|page=133|year=2004|isbn=978-0-8108-4938-9|url={{google books |plainurl=y |id=nzmIPZg5xicC|page=9}}}}</ref> \u2013 one year before DNA's role in [[heredity]] was confirmed by [[Alfred Hershey]] and [[Martha Chase]],<ref>{{cite journal | vauthors = Hershey AD, Chase M | title = Independent functions of viral protein and nucleic acid in growth of bacteriophage | journal = The Journal of General Physiology | volume = 36 | issue = 1 | pages = 39\u201356 | date = May 1952 | pmid = 12981234 | pmc = 2147348 | doi = 10.1085/jgp.36.1.39 }}</ref> and two years before [[James D. Watson|James Watson]] and [[Francis Crick]] showed that the [[DNA]] molecule has a double-helix structure \u2013 though the general concept of direct genetic manipulation was explored in rudimentary form in [[Stanley G. Weinbaum]]'s 1936 science fiction story ''Proteus Island''.<ref>{{cite encyclopedia|url=http://www.sf-encyclopedia.com/entry/genetic_engineering|title=Genetic Engineering|date=2 April 2015|encyclopedia=Encyclopedia of Science Fiction}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=WJrvj0pOJx0C&pg=PA164 |title=Modern Concepts in Nanotechnology, Volume 5|year=2008|isbn=978-81-8356-296-6|publisher=Discovery Publishing House|authors=Shiv Kant Prasad, Ajay Dash}}</ref>\n\n[[File:Jaenisch 2003 by Sam Ogden.jpg|thumb|upright|In 1974 [[Rudolf Jaenisch]] created a [[genetically modified mouse]], the first GM animal.]]\n\nIn 1972, [[Paul Berg]] created the first [[recombinant DNA]] molecules by combining DNA from the monkey virus [[SV40]] with that of the [[Lambda phage|lambda virus]].<ref>{{cite journal | vauthors = Jackson DA, Symons RH, Berg P | title = Biochemical method for inserting new genetic information into DNA of Simian Virus 40: circular SV40 DNA molecules containing lambda phage genes and the galactose operon of Escherichia coli | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 69 | issue = 10 | pages = 2904\u20139 | date = October 1972 | pmid = 4342968 | pmc = 389671 | doi = 10.1073/pnas.69.10.2904 | first8 = David A. Jackson Robert H. Symons and Paul Berg | bibcode = 1972PNAS...69.2904J | doi-access = free }}</ref> In 1973 [[Herbert Boyer]] and [[Stanley Norman Cohen|Stanley Cohen]] created the first [[transgenic organism]] by inserting [[Antibiotic resistance#Applications|antibiotic resistance genes]] into the [[plasmid]] of an ''[[Escherichia coli]]'' bacterium.<ref>{{cite web|title=History of Genetics: Genetic Engineering Timeline|last=Arnold|first=Paul| name-list-style = vanc |year=2009|url=http://www.brighthub.com/science/genetics/articles/21983.aspx}}</ref><ref>{{cite journal | vauthors = Gutschi S, Hermann W, Stenzl W, Tscheliessnigg KH | title = [Displacement of electrodes in pacemaker patients (author's transl)] | journal = Zentralblatt f\u00fcr Chirurgie | volume = 104 | issue = 2 | pages = 100\u20134 | date = 1 May 1973  | pmid = 433482}}</ref> A year later [[Rudolf Jaenisch]] created a [[transgenic mouse]] by introducing foreign DNA into its embryo, making it the world's first [[transgenic animal]]<ref name="pmid4364530">{{cite journal | vauthors = Jaenisch R, Mintz B | title = Simian virus 40 DNA sequences in DNA of healthy adult mice derived from preimplantation blastocysts injected with viral DNA | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 71 | issue = 4 | pages = 1250\u20134 | date = April 1974 | pmid = 4364530 | pmc = 388203 | doi = 10.1073/pnas.71.4.1250| bibcode = 1974PNAS...71.1250J | doi-access = free }}</ref> These achievements led to concerns in the scientific community about potential risks from genetic engineering, which were first discussed in depth at the [[Asilomar Conference on Recombinant DNA|Asilomar Conference]] in 1975. One of the main recommendations from this meeting was that government oversight of recombinant DNA research should be established until the technology was deemed safe.<ref name="ReferenceA">{{cite journal | vauthors = Berg P, Baltimore D, Brenner S, Roblin RO, Singer MF | title = Summary statement of the Asilomar conference on recombinant DNA molecules | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 72 | issue = 6 | pages = 1981\u20134 | date = June 1975 | pmid = 806076 | pmc = 432675 | doi = 10.1073/pnas.72.6.1981 | bibcode = 1975PNAS...72.1981B | doi-access = free }}</ref><ref>{{cite web | title = NIH Guidelines for research involving recombinant DNA molecules | work = Office of Biotechnology Activities | publisher = U.S. Department of Health and Human Services | url = http://oba.od.nih.gov/rdna/nih_guidelines_oba.html | archive-url = https://web.archive.org/web/20120910070047/http://oba.od.nih.gov/rdna/nih_guidelines_oba.html | archive-date = 10 September 2012 | url-status=dead }}</ref>\n\nIn 1976 Genentech, the first genetic engineering company, was founded by Herbert Boyer and [[Robert A. Swanson|Robert Swanson]] and a year later the company produced a human protein ([[somatostatin]]) in ''E.coli''. Genentech announced the production of genetically engineered human [[insulin]] in 1978.<ref name=":0">{{cite journal | vauthors = Goeddel DV, Kleid DG, Bolivar F, Heyneker HL, Yansura DG, Crea R, Hirose T, Kraszewski A, Itakura K, Riggs AD | title = Expression in Escherichia coli of chemically synthesized genes for human insulin | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 76 | issue = 1 | pages = 106\u201310 | date = January 1979 | pmid = 85300 | pmc = 382885 | doi = 10.1073/pnas.76.1.106 | bibcode = 1979PNAS...76..106G | doi-access = free }}</ref> In 1980, the [[U.S. Supreme Court]] in the ''[[Diamond v. Chakrabarty]]'' case ruled that genetically altered life could be patented.<ref>{{cite journal|url=http://supreme.justia.com/us/447/303/case.html |title=Diamond V Chakrabarty|volume=447|author=US Supreme Court Cases from Justia & Oyez|publisher=Supreme.justia.com |date=16 June 1980 |access-date=17 July 2010 |issue=303}}</ref> The [[Insulin (medication)|insulin]] produced by bacteria was approved for release by the [[Food and Drug Administration]] (FDA) in 1982.<ref>{{cite news|url=http://www.time.com/time/magazine/article/0,9171,949646-1,00.html |archive-url=https://web.archive.org/web/20111027011602/http://www.time.com/time/magazine/article/0,9171,949646-1,00.html |url-status=dead |archive-date=27 October 2011 |title=Artificial Genes |work=TIME |date=15 November 1982 |access-date=17 July 2010}}</ref>\n\nIn 1983, a biotech company, Advanced Genetic Sciences (AGS) applied for U.S. government authorisation to perform field tests with the [[Ice-minus bacteria|ice-minus strain]] of ''[[Pseudomonas syringae]]'' to protect crops from frost, but environmental groups and protestors delayed the field tests for four years with legal challenges.<ref>{{cite journal | last1 = Bratspies | first1 = Rebecca | name-list-style = vanc | year = 2007 | title = Some Thoughts on the American Approach to Regulating Genetically Modified Organisms | ssrn = 1017832 | journal = Kansas Journal of Law & Public Policy | volume = 16 | issue = 3 | pages = 101\u201331 }}</ref> In 1987, the ice-minus strain of ''P. syringae'' became the first [[genetically modified organism]] (GMO) to be released into the environment<ref name=BBC2002>BBC News 14 June 2002 [http://news.bbc.co.uk/2/hi/science/nature/2045286.stm GM crops: A bitter harvest?]</ref> when a strawberry field and a potato field in California were sprayed with it.<ref>Thomas H. Maugh II for the Los Angeles Times. 9 June 1987.  [http://articles.latimes.com/1987-06-09/news/mn-6024_1_frost-damage Altered Bacterium Does Its Job : Frost Failed to Damage Sprayed Test Crop, Company Says]</ref> Both test fields were attacked by activist groups the night before the tests occurred: "The world's first trial site attracted the world's first field trasher".<ref name=BBC2002 />\n\nThe first field trials of [[transgenic plants|genetically engineered plants]] occurred in France and the US in 1986, tobacco plants were engineered to be resistant to [[herbicide]]s.<ref>{{cite web |last=James |first=Clive | name-list-style = vanc |title=Global Review of the Field Testing and Commercialization of Transgenic Plants: 1986 to 1995 |url=http://www.isaaa.org/kc/Publications/pdfs/isaaabriefs/Briefs%201.pdf |publisher=The International Service for the Acquisition of Agri-biotech Applications|access-date=17 July 2010 |year=1996}}</ref> The People's Republic of China was the first country to commercialise transgenic plants, introducing a virus-resistant tobacco in 1992.<ref name="James1997">{{cite journal|last=James |first=Clive | name-list-style = vanc |year=1997 |title=Global Status of Transgenic Crops in 1997 |journal=ISAAA Briefs No. 5. |page=31 |url=http://www.isaaa.org/resources/publications/briefs/05/download/isaaa-brief-05-1997.pdf}}</ref> In 1994 [[Monsanto#Spin-offs and mergers|Calgene]] attained approval to commercially release the first [[genetically modified food]], the [[Flavr Savr]], a tomato engineered to have a longer shelf life.<ref>{{cite journal |doi=10.3733/ca.v054n04p6 |title=The case of the FLAVR SAVR tomato |year=2000 | vauthors = Bruening G, Lyons JM |journal=California Agriculture |volume=54 |issue=4 |pages=6\u20137|doi-access=free }}</ref> In 1994, the European Union approved tobacco engineered to be resistant to the herbicide [[bromoxynil]], making it the first genetically engineered crop commercialised in Europe.<ref>{{cite magazine|title=Transgenic tobacco is European first|date=18 June 1994 |last=MacKenzie |first=Debora | name-list-style = vanc |url=https://www.newscientist.com/article/mg14219301.100-transgenic-tobacco-is-european-first.html|magazine=New Scientist}}</ref> In 1995, [[Genetically modified potato#NewLeaf|Bt Potato]] was approved safe by the [[Environmental Protection Agency]], after having been approved by the FDA, making it the first pesticide producing crop to be approved in the US.<ref>[https://news.google.com/newspapers?nid=2199&dat=19950506&id=A0YyAAAAIBAJ&sjid=jOYFAAAAIBAJ&pg=4631,1776980&hl=en Genetically Altered Potato Ok'd For Crops] Lawrence Journal-World \u2013 6 May 1995</ref> In 2009 11 transgenic crops were grown commercially in 25 countries, the largest of which by area grown were the US, Brazil, Argentina, India, Canada, China, Paraguay and South Africa.<ref>[http://www.isaaa.org/resources/publications/briefs/41/executivesummary/default.asp Global Status of Commercialized Biotech/GM Crops: 2009] ISAAA Brief 41-2009, 23 February 2010. Retrieved 10 August 2010</ref>\n\nIn 2010, scientists at the [[J. Craig Venter Institute]] created the first [[synthetic genome]] and inserted it into an empty bacterial cell. The resulting bacterium, named [[Mycoplasma laboratorium]], could [[replicate (biology)|replicate]] and produce proteins.<ref>{{cite journal | vauthors = Pennisi E | title = Genomics. Synthetic genome brings new life to bacterium | journal = Science | volume = 328 | issue = 5981 | pages = 958\u20139 | date = May 2010 | pmid = 20488994 | doi = 10.1126/science.328.5981.958 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Gibson DG, Glass JI, Lartigue C, Noskov VN, Chuang RY, Algire MA, Benders GA, Montague MG, Ma L, Moodie MM, Merryman C, Vashee S, Krishnakumar R, Assad-Garcia N, Andrews-Pfannkoch C, Denisova EA, Young L, Qi ZQ, Segall-Shapiro TH, Calvey CH, Parmar PP, Hutchison CA, Smith HO, Venter JC | display-authors = 6 | title = Creation of a bacterial cell controlled by a chemically synthesized genome | journal = Science | volume = 329 | issue = 5987 | pages = 52\u20136 | date = July 2010 | pmid = 20488990 | doi = 10.1126/science.1190719 | bibcode = 2010Sci...329...52G | citeseerx = 10.1.1.167.1455 | s2cid = 7320517 }}</ref> Four years later this was taken a step further when a bacterium was developed that replicated a [[plasmid]] containing a unique [[base pair]], creating the first organism engineered to use an expanded genetic alphabet.<ref>{{cite journal | vauthors = Malyshev DA, Dhami K, Lavergne T, Chen T, Dai N, Foster JM, Corr\u00eaa IR, Romesberg FE | title = A semi-synthetic organism with an expanded genetic alphabet | journal = Nature | volume = 509 | issue = 7500 | pages = 385\u20138 | date = May 2014 | pmid = 24805238 | pmc = 4058825 | doi = 10.1038/nature13314 | bibcode = 2014Natur.509..385M }}</ref><ref>{{cite journal | vauthors = Thyer R, Ellefson J | s2cid = 4399670 | title = Synthetic biology: New letters for life's alphabet | journal = Nature | volume = 509 | issue = 7500 | pages = 291\u20132 | date = May 2014 | pmid = 24805244 | doi = 10.1038/nature13335 | bibcode = 2014Natur.509..291T | doi-access = free }}</ref> In 2012, [[Jennifer Doudna]] and [[Emmanuelle Charpentier]] collaborated to develop the [[CRISPR|CRISPR/Cas9]] system,<ref>{{Cite news |url=https://www.nytimes.com/2015/05/12/science/jennifer-doudna-crispr-cas9-genetic-engineering.html |title=Jennifer Doudna, a Pioneer Who Helped Simplify Genome Editing|last=Pollack|first=Andrew | name-list-style = vanc |date=2015-05-11 |work=The New York Times |access-date=2017-11-15}}</ref><ref>{{cite journal | vauthors = Jinek M, Chylinski K, Fonfara I, Hauer M, Doudna JA, Charpentier E | title = A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity | journal = Science | volume = 337 | issue = 6096 | pages = 816\u201321 | date = August 2012 | pmid = 22745249 | pmc = 6286148 | doi = 10.1126/science.1225829 | bibcode = 2012Sci...337..816J }}</ref> a technique which can be used to easily and specifically alter the genome of almost any organism.<ref>{{cite journal | vauthors = Ledford H | title = CRISPR: gene editing is just the beginning | journal = Nature | volume = 531 | issue = 7593 | pages = 156\u20139 | date = March 2016 | pmid = 26961639 | doi = 10.1038/531156a | bibcode = 2016Natur.531..156L | doi-access = free }}</ref>"}},
{"article_title": "Gas mask", "pageid": "12772", "revid": "1060750865", "timestamp": "2021-12-17T12:34:30Z", "history_paths": [["Gas mask --- Introduction ---", "History and development"]], "categories": ["american inventions", "british inventions", "iranian inventions", "science and technology in the united kingdom", "military personal equipment", "1914 introductions", "riot control equipment", "gas masks"], "heading_tree": {"Gas mask --- Introduction ---": {"Principles of construction": {"Safety of old gas masks": {}, "Modern filter classification": {}}, "Use": {}, "Shortcomings": {}, "Reaction and exchange": {}, "History and development": {"Early breathing devices": {}, "First World War": {}, "Second World War": {}, "Modern mask": {}}, "In schools": {}, "See also": {}, "Notes": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Gas mask --- Introduction ---|History and development": "According to ''[[Popular Mechanics]]'', "The common sponge was used in [[ancient Greece]] as a gas mask..."<ref>"''[https://books.google.com/books?id=0uMDAAAAMBAJ&pg=PA163-IA2&dq&hl=en#v=onepage&q=&f=false Popular Mechanics]''". January 1984. p. 163</ref> In 1785, [[Jean-Fran\u00e7ois Pil\u00e2tre de Rozier]] invented a [[respirator]].\n\nPrimitive respirator examples were used by [[miner]]s and introduced by [[Alexander von Humboldt]] in 1799, when he worked as a mining engineer in [[Prussia]].<ref>{{Cite book | first=Alexander | last=Von Humboldt | year=1799 | title=Ueber die unterirdischen Gasarten und die Mittel, ihren Nachtheil zu vermindern: Ein Beytrag zur Physik der praktischen Bergbaukunde | publisher=Braunschweig, Friedrich Vieweg | url=https://books.google.com/books?id=LW1oAAAAcAAJ}}</ref> The forerunner to the modern gas mask was invented in 1847 by [[Lewis P. Haslett]], a device that contained elements that allowed breathing through a nose and mouthpiece, inhalation of air through a bulb-shaped filter, and a vent to exhale air back into the atmosphere.<ref>{{cite web|title=The invention of the gas mask|publisher=Ian Taggart|url=http://www33.brinkster.com/iiiii/gasmask/page.html|url-status=dead|archive-url=https://web.archive.org/web/20130502145330/http://www33.brinkster.com/iiiii/gasmask/page.html|archive-date=May 2, 2013}}</ref> ''First Facts'' states that a "gas mask resembling the modern type" was patented by Lewis Phectic Haslett of [[Louisville, Kentucky]], who received a patent on June 12, 1849.<ref name="disu">{{cite book |editor1-last=Su|editor1-first=Di |title=Evolution in Reference and Information Services: The Impact of the Internet |last1=Drobnicki|first1=John A.|last2=Asaro|first2=Richard|chapter=Historical Fabrications on the Internet |publisher=Haworth Information Press|location=Binghamton, New York |year=2001 |page= 144|isbn= 978-0-7890-1723-9 |chapter-url=https://books.google.com/books?id=IvqbuSm4sHYC&q=gas+mask+patent+1849&pg=PA144}}</ref> U.S. patent #6,529<ref>{{Cite patent|title=Lung Protector|inventor-first=Lewis P.|inventor-last=Haslett|gdate=1849-06-12|country=US|number=6529A|inventorlink=Lewis_Haslett}}</ref> issued to Haslett, described the first "Inhaler or Lung Protector" that filtered dust from the air.\n\nEarly versions were constructed by the Scottish chemist John Stenhouse in 1854<ref name="Benson2010">{{cite book|author=Alvin K. Benson|title=Inventors and inventions|url=https://books.google.com/books?id=JqVZAAAAYAAJ|year=2010|publisher=Salem Press|isbn=978-1-58765-526-5}}</ref> and the physicist John Tyndall in the 1870s.<ref>{{cite book|title=The Environment and Its Effect Upon Man: Symposium Held at Harvard School of Public Health, August 24-August 29, 1936, as Part of Harvard University Tercentenary Celebration, 1636-1936|url=https://books.google.com/books?id=WYsaAAAAMAAJ|year=1937|publisher=Harvard School of Public Health}}</ref> Another early design was the "Safety Hood and Smoke Protector" invented by [[Garrett Morgan]] in 1912, and patented in 1914. It was a simple device consisting of a cotton hood with two hoses which hung down to the floor, allowing the wearer to breathe the safer air found there. In addition, moist sponges were inserted at the end of the hoses in order to better filter the air. This was later modified to include its own air supply, leading to World War I era gas masks.<ref>{{Cite book|url=https://books.google.com/books?id=3dXw6gR2GgkC|title=African American Lives|last1=Jr|first1=Henry Louis Gates|last2=Higginbotham|first2=Evelyn Brooks|date=April 29, 2004|publisher=Oxford University Press|isbn=9780199882861|language=en|quote=By World War I, Morgan had modified the mask to carry its own air supply, creating the first gas mask, which by 1917 was standard equipment for the U.S. Army.}}</ref><ref name="pbs.org/wgbh/theymadeamerica2">{{cite web|url=https://www.pbs.org/wgbh/theymadeamerica/whomade/morgan_hi.html|title=Garrett Augustus Morgan|quote=He sold the hoods to the U.S. Navy, and the Army used them in World War I.|work=PBS Who Made America?}}</ref><ref name="encyclopedia.com/topic/Garrett_Morgan2">{{cite encyclopedia|url=http://www.encyclopedia.com/topic/Garrett_Morgan.aspx|title=Morgan, Garrett 1877\u20131963|quote=Morgan would later perfect his \u201cbreathing device\u201d into a gas mask that was used extensively in World War I.|encyclopedia=Encyclopedia.com Contemporary Black Biography}}</ref><ref name="biography.com/people/garrett-morgan2">{{cite web|url=http://www.biography.com/people/garrett-morgan-9414691|title=Garrett Morgan Biography|quote=Morgan's breathing device became the prototype and precursor for the gas masks used during World War I, protecting soldiers from toxic gas used in warfare.|work=Biography.com People}}</ref>\n\n [[Image:Bundesarchiv Bild 183-R52907, Mannschaft mit Gasmasken am Fla-MG.jpg|thumb|German soldiers with gas masks, 1916]]\n\nThe First World War brought about the first need for mass-produced gas masks on both sides because of [[Chemical weapons in World War I|extensive use of chemical weapons]]. The German army successfully used [[chemical weapon|poison gas]] for the first time against Allied troops at the [[Second Battle of Ypres]], Belgium on April 22, 1915.<ref>{{Cite web |url=https://www.history.com/this-day-in-history/second-battle-of-ypres-begins |title=Second Battle of Ypres Begins |website=history.com |access-date=April 22, 2018}}</ref> An immediate response was cotton wool wrapped in muslin, issued to the troops by May 1. This was followed by the [[Black Veil Respirator]], invented by [[John Scott Haldane]], which was a cotton pad soaked in an absorbent solution which was secured over the mouth using black cotton veiling.{{sfn|Wetherell|Mathers|2007|p=157}}\n\nSeeking to improve on the Black Veil respirator, [[Cluny MacPherson]] created a mask made of chemical-absorbing fabric which fitted over the entire head.<ref name="Lefebure">{{cite book | url = https://archive.org/details/riddleofrhineche00lefe | title = The Riddle of the Rhine: Chemical Strategy in Peace and War | year = 1923 | publisher = The Chemical Foundation Inc. | author = Victor Lefebure | isbn = 0-585-23269-5 | url-access = registration }}</ref> A {{cvt|50.5 x 48|cm|in}} canvas hood treated with chlorine-absorbing chemicals, and fitted with a transparent mica eyepiece.<ref name=rooms>{{cite web |url= http://www.rnr.therooms.ca/part3_a_soldiers_outfit.asp |title= Macpherson Gas Hood . Accession #980.222  |publisher=The Rooms Provincial Museum Archives (St. John's, NL) |access-date=August 5, 2017}}</ref> Macpherson presented his idea to the British War Office Anti-Gas Department on May 10, 1915; prototypes were developed soon after.{{sfn|Mayer-Maguire|Baker|2015}} The design was adopted by the British Army and introduced as the [[British Smoke Hood]] in June 1915; Macpherson was appointed to the War Office Committee for Protection against Poisonous Gases.<ref name="RCS">{{Cite web |url=https://livesonline.rcseng.ac.uk/biogs/E005916b.htm |title=Biographical entry Macpherson, Cluny (1879 - 1966)  |website=livesonline.rcseng.ac.uk |access-date=April 22, 2018}}</ref> More elaborate [[sorbent]] compounds were added later to further iterations of his helmet ([[PH helmet]]), to defeat other respiratory poison gases used such as [[phosgene]], [[diphosgene]] and [[chloropicrin]]. In summer and autumn 1915, [[Edward Harrison (chemist)|Edward Harrison]], [[Bertram Lambert]] and [[John Sadd]] developed the [[Large Box Respirator]].<ref name="gasmasknet">{{cite web| url = http://www.gasmasks.net/database/uk/uk.htm | title = The UK | work = The Gas Mask Database }}</ref> This canister gas mask had a tin can containing the absorbent materials by a hose and began to be issued in February 1916. A compact version, the [[Small Box Respirator]], was made a universal issue from August 1916.\n\nIn the first gas masks of World War I, it was initially found that wood charcoal was a good absorbent of poison gases. Around 1918, it was found that charcoals made from the shells and seeds of various fruits and nuts such as [[coconut]]s, [[chestnut]]s, [[horse-chestnut]]s, and [[peach]] stones performed much better than wood [[charcoal]]. These waste materials were collected from the public in recycling programs to assist the war effort.<ref>''Once Worthless Things that have Suddenly Become of Value'', [[Popular Science]] monthly, December 1918, page 80, scanned by [https://books.google.com/books?id=EikDAAAAMBAJ&pg=PA80 Google Books]</ref>\n\nThe first effective filtering [[activated charcoal]] gas mask in the world was invented in 1915 by Russian chemist [[Nikolay Zelinsky]].<ref>{{cite book|last=Kozhevnikov|first=A B|title=Stalin's great science: the times and adventures of Soviet physicists|url=https://books.google.com/books?id=l1Ha_opwB68C|access-date=April 28, 2009|edition=illustrated, reprint|year=2004|publisher=Imperial College Press|isbn= 978-1-86094-419-2|pages=10\u201311}}</ref>\n\n[[File:BunkArt-Horse-Gas-Mask.jpg|thumb|Gas mask for horses|alt=]]\n[[Image:Soldaty 267 Duhovshinskogo polka.jpg|thumb|1916, Russian soldiers]]\nAlso in World War I, since dogs were frequently used on the front lines, a special type of gas mask was developed that dogs were trained to wear.<ref>[https://books.google.com/books?id=EikDAAAAMBAJ&pg=PA75 "Gas-Masks for Dogs / Dumb Heroes of the Fighting Front"], ''[[Popular Science]]'' monthly, December 1918, page 75, Scanned by Google Books</ref> Other gas masks were developed during World War I and the time following for horses in the various mounted units that operated near the front lines.<ref>[https://books.google.com/books?id=LeADAAAAMBAJ&pg=PA75&dq=Popular+Science+1930+plane+%22Popular+Mechanics%22&hl=en&ei=JJlxTqniIc_AtgfAoMD-CQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCsQ6AEwADge#v=onepage&q&f=true "Gas Masks to Guard Horses and Dogs in War"] ''Popular Mechanics'', July 1934, bottom pg. 75</ref> In America, thousands of gas masks were produced for American as well as Allied troops. [[Mine Safety Appliances]] was a chief producer. This mask was later used widely in industry.<ref name="ReferenceA">Pittsburgh Post-Gazette, November 30, 1960</ref>\n\n [[File:Air Raid Precautions on the British Home Front- Anti-gas Instruction, c 1941 D3948.jpg|thumbnail|right|A British couple wearing gas masks in their home in 1941]]\n{{anchor|WWII gas mask}}\nThe British Respirator, Anti-Gas (Light) was developed in 1943 by the British.<ref>{{Cite web|url=https://www.iwm.org.uk/collections/item/object/30016346|title = Respirator, Anti-Gas (Light) MKII: With Haversack Carrier & contents}}</ref> It was made of plastic and rubber-like material that greatly reduced the weight and bulk compared to World War I gas masks, and fitted the user's face more snugly and comfortably. The main improvement was replacing the separate filter canister connected with a hose by an easily replaceable filter canister screwed on the side of the gas mask. Also, it had replaceable plastic lenses.\n\n Gas mask development since has mirrored the development of chemical agents in warfare, filling the need to protect against ever more deadly threats, biological weapons, and radioactive dust in the nuclear era. However, for agents that cause harm through contact or penetration of the skin, such as [[blister agent]] or [[nerve agent]], a gas mask alone is not sufficient protection, and full protective clothing must be worn in addition to protect from contact with the atmosphere. For reasons of civil defence and personal protection, individuals often buy gas masks since they believe that they protect against the harmful effects of an attack with nuclear, biological, or chemical ([[chemical, biological, radiological, and nuclear|NBC]]) agents, which is only partially true, as gas masks protect only against respiratory absorption. Most military gas masks are designed to be capable of protecting against all NBC agents, but they can have filter canisters proof against those agents (heavier) or only against [[riot control agent]]s and smoke (lighter and often used for training purposes). There are lightweight masks solely for protection against riot-control agents and not for NBC situations.{{citation needed|date=March 2017}}\n\nAlthough thorough training and the availability of gas masks and other protective equipment can nullify the casualty-causing effects of an attack by chemical agents, troops who are forced to operate in full protective gear are less efficient in completing tasks, tire easily, and may be affected psychologically by the threat of attack by those weapons. During the [[Cold War]], it was seen as inevitable that there would be a constant NBC threat on the battlefield and so troops needed protection in which they could remain fully functional; thus, protective gear and especially gas masks have evolved to incorporate innovations in terms of increasing user comfort and compatibility with other equipment (from drinking devices to artificial respiration tubes, to communications systems etc.).\n\n[[File:Chemical weapon1.jpg|thumb|Iranian soldier wearing a US M17 protective mask on the frontline of the [[Iran\u2013Iraq War]]]]\nDuring the [[Iran\u2013Iraq War]] (1980\u201388), Iraq developed [[Iraqi chemical weapons program|its chemical weapons program]] with the help of European countries such as Germany and France<ref>{{Cite web|title=Iraqi Scientist Reports on German, Other Help for Iraq Chemical Weapons Program|url=https://fas.org/nuke/guide/iraq/cw/az120103.html|access-date=2021-06-28|website=fas.org}}</ref> and used them in a large scale against Iranians and Iraqi Kurds. Iran was unprepared for chemical warfare. In 1984, Iran received gas masks from the [[Republic of Korea]] and [[East Germany]], but the Korean masks were not suited for the faces of non-[[East Asian people]], the filter lasted for only 15 minutes, and the 5,000 masks bought from East Germany proved to be not gas masks but spray-painting goggles. As late as 1986, Iranian diplomats still travelled in Europe to buy [[active charcoal]] and models of filters to produce defensive gear domestically. In April 1988, Iran started domestic production of gas masks by the Iran Yasa factories.<ref>{{Cite web|url=http://cns.miis.edu/archive/cns/programs/dc/briefs/030701.htm |title=Iranian Use of Chemical Weapons: A Critical Analysis of Past Allegations |last=Zanders |first=Jean Pascal |date=March 7, 2001 |website=CNS Briefings |publisher=James Martin Center for Nonproliferation Studies |access-date=March 27, 2016 |url-status=dead |archive-url=https://web.archive.org/web/20150320222016/http://cns.miis.edu/archive/cns/programs/dc/briefs/030701.htm |archive-date=March 20, 2015 }}</ref>"}},
{"article_title": "Greek fire", "pageid": "12822", "revid": "1058959893", "timestamp": "2021-12-06T16:34:27Z", "history_paths": [["Greek fire --- Introduction ---", "History"]], "categories": ["flamethrowers", "byzantine military equipment", "greek inventions", "incendiary weapons", "medieval artillery", "byzantine science", "byzantine navy", "technology in the middle ages", "naval weapons", "lost inventions"], "heading_tree": {"Greek fire --- Introduction ---": {"History": {}, "Manufacture": {"General characteristics": {}, "Theories on composition": {}}, "Methods of deployment": {"Projectors": {}, "Hand-held projectors": {}, "Grenades": {}}, "Effectiveness and countermeasures": {}, "In literature": {}, "See also": {}, "References": {"Citations": {}, "Sources": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Greek fire --- Introduction ---|History": "{{Further|Early thermal weapons|Byzantine navy}}\nIncendiary and flaming weapons were used in warfare for centuries before Greek fire was invented. They included a number of sulfur-, [[petroleum]]-, and [[bitumen]]-based mixtures.{{sfn|Leicester|1971|p=75}}{{sfn|Crosby|2002|pp=88\u201389}} Incendiary arrows and pots containing combustible substances surrounded by caltrops or spikes, or launched by catapults, were used as early as the 9th century BC by the [[Neo-Assyrian Empire|Assyrians]] and were extensively used in the Greco-Roman world as well. Furthermore, [[Thucydides]] mentions that in the [[Battle of Delium|siege of Delium]] in 424 BC a long tube on wheels was used which blew flames forward using a large [[bellows]].{{sfn|Partington|1999|pp=1\u20135}}{{sfn|Forbes|1959|pp=70\u201374}}<ref>Thuc. 4.100.1</ref> The Roman author [[Sextus Julius Africanus|Julius Africanus]], writing in the 3rd century AD, records a mixture that ignited from adequate heat and intense sunlight, used in grenades or night attacks:<blockquote>Automatic fire also by the following formula. This is the recipe: take equal amounts of sulphur, rock salt, ashes, thunder stone, and pyrite and pound fine in a black mortar at midday sun. Also in equal amounts of each ingredient mix together black mulberry resin and Zakynthian asphalt, the latter in a liquid form and free-flowing, resulting in a product that is sooty colored. Then add to the asphalt the tiniest amount of quicklime. But because the sun is at its zenith, one must pound it carefully and protect the face, for it will ignite suddenly. When it catches fire, one should seal it in some sort of copper receptacle; in this way you will have it available in a box, without exposing it to the sun. If you should wish to ignite enemy armaments, you will smear it on in the evening, either on the armaments or some other object, but in secret; when the sun comes up, everything will be burnt up.<ref>Julius Africanus, ''The Cestus'', D25, 116\u2013117.</ref></blockquote> In naval warfare, the Byzantine emperor [[Anastasius I (emperor)|Anastasius I]] ({{reign|491|518}}) is recorded by chronicler [[John Malalas]] to have been advised by a philosopher from [[Athens]] called Proclus to use sulfur to burn the ships of the rebel general [[Vitalian (general)|Vitalian]].{{sfn|Partington|1999|p=5}}\n\nGreek fire proper, however, was developed in {{circa|672}} and is ascribed by the chronicler [[Theophanes the Confessor]] to [[Callinicus of Heliopolis|Kallinikos]] (Latinized Callinicus), an architect from [[Heliopolis (Syria)|Heliopolis]] in the former [[Roman province|province]] of [[Phoenice (Roman province)|Phoenice]], by then overrun by the [[Muslim conquests]]:{{sfn|Pryor|Jeffreys|2006|pp=607\u2013609}}\n\n{{quote|At that time Kallinikos, an artificer from Heliopolis, fled to the Romans. He had devised a sea fire which ignited the Arab ships and burned them with all hands. Thus it was that the Romans returned with victory and discovered the sea fire.{{sfn|Theophanes|Turtledove|1982|p=53}}}}\n\nThe accuracy and exact chronology of this account is open to question: elsewhere, Theophanes reports the use of fire-carrying ships equipped with nozzles (''siph\u014dn'') by the Byzantines a couple of years before the supposed arrival of Kallinikos at Constantinople.{{sfn|Theophanes|Turtledove|1982|p=52}} If this is not due to chronological confusion of the events of the siege, it may suggest that Kallinikos merely introduced an improved version of an established weapon.{{sfn|Roland|1992|p=657}}{{sfn|Pryor|Jeffreys|2006|p=608}} The historian [[J. R. Partington|James Partington]] further thinks it likely that Greek fire was not in fact the creation of any single person but "invented by chemists in Constantinople who had inherited the discoveries of the [[Alexandria]]n chemical school."{{sfn|Partington |1999|pp=12\u201313}} Indeed, the 11th-century chronicler [[George Kedrenos]] records that Kallinikos came from [[Heliopolis (Ancient Egypt)|Heliopolis in Egypt]], but most scholars reject this as an error.{{sfn|Forbes|1959|p=80}} Kedrenos also records the story, considered rather implausible by modern scholars, that Kallinikos' descendants, a family called ''Lampros'', "brilliant," kept the secret of the fire's manufacture and continued doing so to Kedrenos' time.{{sfn|Pryor|Jeffreys|2006|p=608}}\n\nKallinikos' development of Greek fire came at a critical moment in the Byzantine Empire's history: weakened by its long [[Roman\u2013Persian Wars|wars]] with [[Sassanid Persia]], the Byzantines had been unable to effectively resist the onslaught of the [[Muslim conquests]]. Within a generation, Syria, Palestine, and Egypt had fallen to the Arabs, who in {{c.|lk=no|672}} set out to conquer the imperial capital of [[Constantinople]]. Greek fire was used to great effect against the Muslim fleets, helping to repel the Muslims at the [[Siege of Constantinople (674\u2013678)|first]] and [[Siege of Constantinople (718)|second]] Arab sieges of the city.{{sfn|Pryor|Jeffreys|2006|pp=26\u201327, 31\u201332}} Records of its use in later naval battles against the [[Saracen]]s are more sporadic, but it did secure a number of victories, especially in the phase of Byzantine expansion in the late 9th and early 10th centuries.{{sfn|Pryor|Jeffreys|2006|pp=61\u201362, 72}} Utilisation of the substance was prominent in Byzantine civil wars, chiefly the revolt of the thematic fleets in 727 and the large-scale rebellion led by [[Thomas the Slav]] in 821\u2013823. In both cases, the rebel fleets were defeated by the Constantinople-based central Imperial Fleet through the use of Greek fire.{{sfn|Pryor|Jeffreys|2006|pp=32, 46, 73}} The Byzantines also used the weapon to devastating effect against the various [[Rus' people|Rus']] raids on the [[Bosphorus|Bosporus]], especially those of [[Rus'\u2013Byzantine War (941)|941]] and [[Rus'\u2013Byzantine War (1043)|1043]], as well as during the [[Rus'\u2013Byzantine War (970\u2013971)|Bulgarian war of 970\u2013971]], when the fire-carrying Byzantine ships blockaded the Danube.{{sfn|Pryor|Jeffreys|2006|pp=86, 189}}\n\nThe importance placed on Greek fire during the Empire's struggle against the Arabs would lead to its discovery being ascribed to divine intervention. The Emperor [[Constantine VII|Constantine Porphyrogennetos]] ({{reign|945|959}}), in his book ''[[De Administrando Imperio]]'', admonishes his son and heir, [[Romanos II]] ({{reign|959|963}}), to never reveal the secrets of its composition, as it was "shown and revealed by an angel to the great and holy first Christian emperor [[Constantine I|Constantine]]" and that the angel bound him "not to prepare this fire but for Christians, and only in the imperial city." As a warning, he adds that one official, who was bribed into handing some of it over to the Empire's enemies, was struck down by a "flame from heaven" as he was about to enter a church.{{sfn|Moravcsik|Jenkins|1967|pp=68\u201371}}{{sfn|Forbes|1959|p=82}} As the latter incident demonstrates, the Byzantines could not avoid capture of their precious secret weapon: the Arabs captured at least one fireship intact in 827, and the Bulgars captured several ''siph\u014dn''s and much of the substance itself in 812/814. This, however, was apparently not enough to allow their enemies to copy it (see [[#General characteristics|below]]). The Arabs, for instance, employed a variety of incendiary substances similar to the Byzantine weapon, but they were never able to copy the Byzantine method of deployment by ''siph\u014dn'', and used catapults and grenades instead.{{sfn|Pryor|Jeffreys|2006|pp=609\u2013611}}{{sfn|Roland|1992|pages=660, 663\u2013664}}\n\nGreek fire continued to be mentioned during the 12th century, and [[Anna Komnene]] gives a vivid description of its use in a naval battle against the [[Pisa]]ns in 1099.{{sfn|Pryor|Jeffreys|2006|p=110}} However, although the use of hastily improvised [[fireships]] is mentioned during the [[Siege of Constantinople (1203)|1203 siege]] of Constantinople by the [[Fourth Crusade]], no report confirms the use of the actual Greek fire. This might be because of the general disarmament of the Empire in the 20 years leading up to the sacking, or because the Byzantines had lost access to the areas where the primary ingredients were to be found, or even perhaps because the secret had been lost over time.{{sfn|Pryor|Jeffreys|2006|pp=630\u2013631}}{{sfn|Haldon|2006|p=316}}\n\nRecords of a 13th-century event in which "Greek fire" was used by the Saracens against the Crusaders can be read through the Memoirs of the Lord of Joinville during the [[Seventh Crusade]].  One description of the memoir says "the tail of fire that trailed behind it was as big as a great spear; and it made such a noise as it came, that it sounded like the thunder of heaven. It looked like a dragon flying through the air. Such a bright light did it cast, that one could see all over the camp as though it were day, by reason of the great mass of fire, and the brilliance of the light that it shed."<ref>{{cite web|url=http://www.lordsandladies.org/greek-fire.htm|title=Greek Fire|website=The Middle Ages (www.lordsandladies.org)|first=Linda|last=Alchin}}</ref>\n\nIn the 19th century, it is reported that an [[Armenians|Armenian]] by the name of Kavafian approached the government of the [[Ottoman Empire]] with a new type of Greek fire he claimed to have developed. Kavafian refused to reveal its composition when asked by the government, insisting that he be placed in command of its use during naval engagements. Not long after this, he was poisoned by imperial authorities, without their ever having found out his secret.<ref>{{in lang|hy}} [[Hrachia Adjarian|Adjarian, Hrachia]]. "\u0540\u0561\u0575\u0578\u0581 \u0564\u0565\u0580\u0568 \u0555\u057d\u0574\u0561\u0576\u0575\u0561\u0576 \u056f\u0561\u0575\u057d\u0580\u0578\u0582\u0569\u0575\u0561\u0576 \u0574\u0565\u057b," [The role of Armenians in the Ottoman Empire] ''Banber Erevani Hamalsarani'' 1967; trans. in Charles Issawi, ''The Economic History of Turkey, 1800\u20131914'', Chicago: University of Chicago Press, 1980, p. 64.</ref>"}},
{"article_title": "Gene therapy", "pageid": "12891", "revid": "1062237676", "timestamp": "2021-12-27T06:19:24Z", "history_paths": [["Gene therapy --- Introduction ---", "History"]], "categories": ["gene therapy", "applied genetics", "bioethics", "biotechnology", "medical genetics", "molecular biology", "gene delivery", "emerging technologies", "1989 introductions", "1996 introductions", "1989 in biotechnology", "genetic engineering"], "heading_tree": {"Gene therapy --- Introduction ---": {"Background": {}, "Cell types": {"Somatic": {}, "Germline": {}}, "Vectors": {"Viruses": {}, "Non-viral": {}, "In vivo versus ex vivo therapies": {}}, "Gene doping": {}, "Human genetic engineering": {}, "Treatment of genetic diseases": {"List of gene therapies for treatment of disease": {}}, "Adverse effects, contraindications and hurdles for use": {"Deaths": {}}, "Regulations": {"United States": {}}, "History": {"1970s and earlier": {}, "1980s": {}, "1990s": {}, "2000s": {"2002": {}, "2003": {}, "2006": {}, "2007": {}, "2008": {}, "2009": {}}, "2010s": {"2010": {}, "2011": {}, "2012": {}, "2013": {}, "2014": {}, "2015": {}, "2016": {}, "2017": {}, "2019": {}}, "2020s": {"2020": {}, "2021": {}}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Gene therapy --- Introduction ---|History": "{{Summarize section|date=November 2018}}\n\n In 1972 Friedmann and Roblin authored a paper in ''[[Science (journal)|Science]]'' titled "Gene therapy for human genetic disease?".<ref name="Friedman 1972">{{cite journal | vauthors = Friedmann T, Roblin R | title = Gene therapy for human genetic disease? | journal = Science | volume = 175 | issue = 4025 | pages = 949\u2013955 | date = March 1972 | pmid = 5061866 | doi = 10.1126/science.175.4025.949 | bibcode = 1972Sci...175..949F | s2cid = 19952096 }}</ref> Rogers (1970) was cited for proposing that ''exogenous good DNA'' be used to replace the defective DNA in those who suffer from genetic defects.<ref>Rogers S, New Scientist 1970, p. 194</ref>\n\n In 1984 a retrovirus vector system was designed that could efficiently insert foreign genes into mammalian chromosomes.<ref>{{cite journal | vauthors = Cepko CL, Roberts BE, Mulligan RC | title = Construction and applications of a highly transmissible murine retrovirus shuttle vector. This Vector is used for entering a cell in the humans cell body. | journal = Cell | volume = 37 | issue = 3 | pages = 1053\u20131062 | date = July 1984 | pmid = 6331674 | doi = 10.1016/0092-8674(84)90440-9 | s2cid = 34544709 }}</ref>\n\n The first approved gene therapy clinical research in the US took place on 14 September 1990, at the [[National Institutes of Health]] (NIH), under the direction of [[William French Anderson]].<ref>{{cite web|url=http://www.lifesciencesfoundation.org/printer_events-The_first_gene_therapy.html |title=The first gene therapy |publisher=Life Sciences Foundation |date=21 June 2011 |access-date=7 January 2014 |url-status=dead |archive-url=https://web.archive.org/web/20121128203817/http://www.lifesciencesfoundation.org/printer_events-The_first_gene_therapy.html |archive-date=28 November 2012 }}</ref> Four-year-old Ashanti DeSilva received treatment for a genetic defect that left her with [[adenosine deaminase deficiency]] (ADA-SCID), a severe immune system deficiency. The defective gene of the patient's blood cells was replaced by the functional variant. Ashanti's immune system was partially restored by the therapy. Production of the missing enzyme was temporarily stimulated, but the new cells with functional genes were not generated. She led a normal life only with the regular injections performed every two months. The effects were successful, but temporary.<ref>{{cite journal | vauthors = Blaese RM, Culver KW, Miller AD, Carter CS, Fleisher T, Clerici M, Shearer G, Chang L, Chiang Y, Tolstoshev P, Greenblatt JJ, Rosenberg SA, Klein H, Berger M, Mullen CA, Ramsey WJ, Muul L, Morgan RA, Anderson WF | display-authors = 6 | title = T lymphocyte-directed gene therapy for ADA- SCID: initial trial results after 4 years | journal = Science | volume = 270 | issue = 5235 | pages = 475\u2013480 | date = October 1995 | pmid = 7570001 | doi = 10.1126/science.270.5235.475 | bibcode = 1995Sci...270..475B | s2cid = 46339645 | url = https://zenodo.org/record/1231045 }}</ref>\n\nCancer gene therapy was introduced in 1992/93 (Trojan et al. 1993).<ref>{{cite journal | vauthors = Trojan J, Johnson TR, Rudin SD, Ilan J, Tykocinski ML, Ilan J | title = Treatment and prevention of rat glioblastoma by immunogenic C6 cells expressing antisense insulin-like growth factor I RNA | journal = Science | volume = 259 | issue = 5091 | pages = 94\u201397 | date = January 1993 | pmid = 8418502 | doi = 10.1126/science.8418502 | bibcode = 1993Sci...259...94T }}</ref> The treatment of glioblastoma multiforme, the malignant brain tumor whose outcome is always fatal, was done using a vector expressing antisense IGF-I RNA (clinical trial approved by NIH protocol no.1602 24 November 1993,<ref name="pmid22400112">{{cite journal | vauthors = Trojan J, Pan YX, Wei MX, Ly A, Shevelev A, Bierwagen M, Ardourel MY, Trojan LA, Alvarez A, Andres C, Noguera MC, Briceno I, Aristizabal BH, Kasprzak H, Duc HT, Anthony DD | display-authors = 6 | title = Methodology for Anti-Gene Anti-IGF-I Therapy of Malignant Tumours | journal = Chemotherapy Research and Practice | volume = 2012 | pages = 1\u201312 | year = 2012 | pmid = 22400112 | pmc = 3287029 | doi = 10.1155/2012/721873 | doi-access = free }}</ref> and by the FDA in 1994). This therapy also represents the beginning of cancer immunogene therapy, a treatment which proves to be effective due to the anti-tumor mechanism of IGF-I antisense, which is related to strong immune and apoptotic phenomena.\n\nIn 1992 [[Claudio Bordignon]], working at the [[Vita-Salute San Raffaele University]], performed the first gene therapy procedure using [[hematopoietic stem cell]]s as vectors to deliver genes intended to correct [[hereditary diseases]].<ref>{{cite journal | vauthors = Abbott A | title = Gene therapy. Italians first to use stem cells | journal = Nature | volume = 356 | issue = 6369 | pages = 465 | date = April 1992 | pmid = 1560817 | doi = 10.1038/356465a0 | bibcode = 1992Natur.356..465A | s2cid = 4319842 }}</ref> In 2002 this work led to the publication of the first successful gene therapy treatment for ADA-SCID. The success of a multi-center trial for treating children with SCID ([[severe combined immune deficiency]] or "bubble boy" disease) from 2000 and 2002, was questioned when two of the ten children treated at the trial's Paris center developed a leukemia-like condition. Clinical trials were halted temporarily in 2002, but resumed after regulatory review of the protocol in the US, the United Kingdom, France, Italy, and Germany.<ref>{{cite journal | vauthors = Cavazzana-Calvo M, Thrasher A, Mavilio F | title = The future of gene therapy | journal = Nature | volume = 427 | issue = 6977 | pages = 779\u2013781 | date = February 2004 | pmid = 14985734 | doi = 10.1038/427779a | bibcode = 2004Natur.427..779C | s2cid = 4421364 }}</ref>\n\nIn 1993 Andrew Gobea was born with SCID following prenatal [[genetic screening]]. Blood was removed from his mother's [[placenta]] and [[umbilical cord]] immediately after birth, to acquire stem cells. The [[allele]] that codes for [[adenosine deaminase]] (ADA) was obtained and inserted into a retrovirus. Retroviruses and stem cells were mixed, after which the viruses inserted the gene into the stem cell chromosomes. Stem cells containing the working ADA gene were injected into Andrew's blood. Injections of the ADA enzyme were also given weekly. For four years [[T cell]]s (white blood cells), produced by stem cells, made ADA enzymes using the ADA gene. After four years more treatment was needed.<ref>{{Cite news|url=https://www.nytimes.com/1993/05/18/science/treatment-for-bubble-boy-disease.html|title=Treatment for 'Bubble Boy Disease'|last1=S|date=1993-05-18|work=The New York Times|access-date=2018-02-09|last2=Blakeslee|first2=Ra|issn=0362-4331}}</ref>\n\n[[Jesse Gelsinger]]'s death in 1999 impeded gene therapy research in the US.<ref>{{cite news|url=https://www.washingtonpost.com/wp-dyn/content/article/2010/10/11/AR2010101102946.html |title=First patient treated in stem cell study |newspaper=The Washington Post |date= 11 October 2010 | last = Stein | first = Rob | name-list-style = vanc | access-date = 10 November 2010 }}</ref><ref>{{cite web|url=http://www.medpagetoday.com/Genetics/GeneralGenetics/6275 |title=Death Prompts FDA to Suspend Arthritis Gene Therapy Trial |publisher=Medpage Today |date= 27 July 2007 |access-date=10 November 2010}}</ref> As a result, the FDA suspended several clinical trials pending the reevaluation of ethical and procedural practices.<ref>{{cite news|url=https://www.nytimes.com/2000/01/22/us/gene-therapy-ordered-halted-at-university.html | last = Stolberg | first = Sheryl Gay | name-list-style = vanc | title=Gene Therapy Ordered Halted At University |work=The New York Times |date=22 January 2000 |access-date=10 November 2010}}</ref>\n\n The modified cancer gene therapy strategy of antisense IGF-I RNA (NIH n\u02da 1602)<ref name="pmid22400112" /> using antisense / triple helix anti-IGF-I approach was registered in 2002 by Wiley gene therapy clinical trial - n\u02da 635 and 636. The approach has shown promising results in the treatment of six different malignant tumors: glioblastoma, cancers of liver, colon, prostate, uterus, and ovary (Collaborative NATO Science Programme on Gene Therapy USA, France, Poland n\u02da LST 980517 conducted by J. Trojan) (Trojan et al., 2012). This anti-gene antisense/triple helix therapy has proven to be efficient, due to the mechanism stopping simultaneously IGF-I expression on translation and transcription levels, strengthening anti-tumor immune and apoptotic phenomena.\n\n [[Sickle-cell disease]] can be treated in mice.<ref>{{cite web|url=http://www.the-scientist.com/article/display/12938/ |title=Murine Gene Therapy Corrects Symptoms of Sickle Cell Disease|work=The Scientist \u2013 Magazine of the Life Sciences| last = Wilson | first = Jennifer Fisher | name-list-style = vanc |date=18 March 2002 |access-date=17 August 2010}}</ref> The mice \u2013 which have essentially the same defect that causes human cases \u2013 used a viral vector to induce production of [[fetal hemoglobin]] (HbF), which normally ceases to be produced shortly after birth. In humans, the use of [[hydroxyurea]] to stimulate the production of HbF temporarily alleviates sickle cell symptoms. The researchers demonstrated this treatment to be a more permanent means to increase therapeutic HbF production.<ref name="St Jude">{{cite web|last=St. Jude Children's Research Hospital|title=Gene Therapy Corrects Sickle Cell Disease In Laboratory Study|url=https://www.sciencedaily.com/releases/2008/12/081203184643.htm|website=ScienceDaily|access-date=29 December 2012|date=4 December 2008}}</ref>\n\nA new gene therapy approach repaired errors in [[messenger RNA]] derived from defective genes. This technique has the potential to treat [[thalassaemia]], [[cystic fibrosis]] and some cancers.<ref>{{cite web|url=https://www.newscientist.com/article/dn2915-subtle-gene-therapy-tackles-blood-disorder.html |title=Subtle gene therapy tackles blood disorder |date= 11 October 2002| last = Penman | first = Danny | name-list-style = vanc |work=New Scientist |access-date=17 August 2010}}</ref>\n\nResearchers created [[liposomes]] 25 nanometers across that can carry therapeutic DNA through pores in the [[nuclear membrane]].<ref>{{cite web|url=https://www.newscientist.com/article/dn2257-dna-nanoballs-boost-gene-therapy.html |title=DNA nanoballs boost gene therapy |work=New Scientist |date=12 May 2002 |access-date=17 August 2010}}</ref>\n\n In 2003 a research team inserted genes into the brain for the first time. They used [[liposomes]] coated in a [[polymer]] called [[polyethylene glycol]], which unlike viral vectors, are small enough to cross the [[blood\u2013brain barrier]].<ref>{{cite web|url=https://www.newscientist.com/article/dn3520-undercover-genes-slip-into-the-brain.html | last = Ananthaswamy | first = Anil | name-list-style = vanc |title=Undercover genes slip into the brain |work=New Scientist |date=20 March 2003 |access-date=17 August 2010}}</ref>\n\nShort pieces of [[double-stranded RNA]] (short, interfering RNAs or [[siRNA]]s) are used by cells to degrade RNA of a particular sequence. If a siRNA is designed to match the RNA copied from a faulty gene, then the abnormal protein product of that gene will not be produced.<ref>{{cite web|url=https://www.newscientist.com/article/dn3493-gene-therapy-may-switch-off-huntingtons.html |title=Gene therapy may switch off Huntington's |work=New Scientist |date=13 March 2003 |access-date=17 August 2010| last = Holmes | first = Bob | name-list-style = vanc }}</ref>\n\n[[Gendicine]] is a cancer gene therapy that delivers the [[tumor suppressor]] gene [[p53]] using an engineered [[adenovirus]]. In 2003, it was approved in China for the treatment of [[Head and neck cancer|head and neck squamous cell carcinoma]].<ref name="Gend" />\n\n In March researchers announced the successful use of gene therapy to treat two adult patients for X-linked [[chronic granulomatous disease]], a disease which affects [[myeloid]] cells and damages the [[immune system]]. The study is the first to show that gene therapy can treat the [[myeloid]] system.<ref>{{cite journal | vauthors = Ott MG, Schmidt M, Schwarzwaelder K, Stein S, Siler U, Koehl U, Glimm H, K\u00fchlcke K, Schilz A, Kunkel H, Naundorf S, Brinkmann A, Deichmann A, Fischer M, Ball C, Pilz I, Dunbar C, Du Y, Jenkins NA, Copeland NG, L\u00fcthi U, Hassan M, Thrasher AJ, Hoelzer D, von Kalle C, Seger R, Grez M | display-authors = 6 | title = Correction of X-linked chronic granulomatous disease by gene therapy, augmented by insertional activation of MDS1-EVI1, PRDM16 or SETBP1 | journal = Nature Medicine | volume = 12 | issue = 4 | pages = 401\u2013409 | date = April 2006 | pmid = 16582916 | doi = 10.1038/nm1393 | s2cid = 7601162 | url = http://www.medscape.com/viewarticle/531129 }}</ref>\n\nIn May a team reported a way to prevent the immune system from rejecting a newly delivered gene.<ref>{{cite journal | vauthors = Brown BD, Venneri MA, Zingale A, Sergi Sergi L, Naldini L | title = Endogenous microRNA regulation suppresses transgene expression in hematopoietic lineages and enables stable gene transfer | journal = Nature Medicine | volume = 12 | issue = 5 | pages = 585\u2013591 | date = May 2006 | pmid = 16633348 | doi = 10.1038/nm1398 | s2cid = 11114427 }}</ref> Similar to [[organ transplant]]ation, gene therapy has been plagued by this problem. The [[immune system]] normally recognizes the new gene as foreign and rejects the cells carrying it. The research utilized a newly uncovered network of genes regulated by molecules known as [[microRNA]]s. This natural function selectively obscured their therapeutic gene in immune system cells and protected it from discovery. Mice infected with the gene containing an immune-cell microRNA target sequence did not reject the gene.\n\nIn August scientists successfully treated metastatic [[melanoma]] in two patients using [[Cytotoxic T cell|killer T cells]] genetically retargeted to attack the cancer cells.<ref>{{cite journal | vauthors = Morgan RA, Dudley ME, Wunderlich JR, Hughes MS, Yang JC, Sherry RM, Royal RE, Topalian SL, Kammula US, Restifo NP, Zheng Z, Nahvi A, de Vries CR, Rogers-Freezer LJ, Mavroukakis SA, Rosenberg SA | display-authors = 6 | title = Cancer regression in patients after transfer of genetically engineered lymphocytes | journal = Science | volume = 314 | issue = 5796 | pages = 126\u2013129 | date = October 2006 | pmid = 16946036 | pmc = 2267026 | doi = 10.1126/science.1129003 | bibcode = 2006Sci...314..126M }}</ref>\n\nIn November researchers reported on the use of VRX496, a gene-based [[immunotherapy]] for the treatment of [[HIV]] that uses a [[lentivirus|lentiviral]] [[viral vector|vector]] to deliver an [[Sense (molecular biology)|antisense]] gene against the [[HIV envelope]]. In a [[phase I clinical trial]], five subjects with chronic HIV infection who had failed to respond to at least two [[antiretroviral]] regimens were treated. A single intravenous infusion of [[autologous]] [[CD4]] T cells genetically modified with VRX496 was well tolerated. All patients had stable or decreased viral load; four of the five patients had stable or increased CD4 T cell counts. All five patients had stable or increased immune response to HIV [[antigen]]s and other [[pathogen]]s. This was the first evaluation of a lentiviral vector administered in a US human clinical trial.<ref>{{cite journal | vauthors = Levine BL, Humeau LM, Boyer J, MacGregor RR, Rebello T, Lu X, Binder GK, Slepushkin V, Lemiale F, Mascola JR, Bushman FD, Dropulic B, June CH | display-authors = 6 | title = Gene transfer in humans using a conditionally replicating lentiviral vector | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 103 | issue = 46 | pages = 17372\u201317377 | date = November 2006 | pmid = 17090675 | pmc = 1635018 | doi = 10.1073/pnas.0608138103 | bibcode = 2006PNAS..10317372L | doi-access = free }}</ref><ref>{{cite web|url=http://www.eurekalert.org/pub_releases/2009-02/uops-pmp021009.php|date=10 February 2009|title=Penn Medicine presents HIV gene therapy trial data at CROI 2009|access-date=19 November 2009|website=EurekAlert!}}</ref>\n\n In May researchers announced the first gene therapy trial for inherited [[retinal disease]]. The first operation was carried out on a 23-year-old British male, Robert Johnson, in early 2007.<ref>{{cite news| url=http://news.bbc.co.uk/1/hi/health/6609205.stm | work=BBC News | title=Gene therapy first for poor sight | date=1 May 2007 | access-date=3 May 2010}}</ref>\n\n {{Main|Gene therapy of the human retina}}\n\n[[Leber's congenital amaurosis]] is an inherited blinding disease caused by mutations in the [[RPE65]] gene. The results of a small clinical trial in children were published in April.<ref name="Maguire 2008"/> Delivery of recombinant [[adeno-associated virus]] (AAV) carrying RPE65 yielded positive results. In May two more groups reported positive results in independent clinical trials using gene therapy to treat the condition. In all three clinical trials, patients recovered functional vision without apparent side-effects.<ref name="Maguire 2008">{{cite journal | vauthors = Maguire AM, Simonelli F, Pierce EA, Pugh EN, Mingozzi F, Bennicelli J, Banfi S, Marshall KA, Testa F, Surace EM, Rossi S, Lyubarsky A, Arruda VR, Konkle B, Stone E, Sun J, Jacobs J, Dell'Osso L, Hertle R, Ma JX, Redmond TM, Zhu X, Hauck B, Zelenaia O, Shindler KS, Maguire MG, Wright JF, Volpe NJ, McDonnell JW, Auricchio A, High KA, Bennett J | display-authors = 6 | title = Safety and efficacy of gene transfer for Leber's congenital amaurosis | journal = The New England Journal of Medicine | volume = 358 | issue = 21 | pages = 2240\u20132248 | date = May 2008 | pmid = 18441370 | pmc = 2829748 | doi = 10.1056/NEJMoa0802315 }}</ref><ref name="Simonelli 2010">{{cite journal | vauthors = Simonelli F, Maguire AM, Testa F, Pierce EA, Mingozzi F, Bennicelli JL, Rossi S, Marshall K, Banfi S, Surace EM, Sun J, Redmond TM, Zhu X, Shindler KS, Ying GS, Ziviello C, Acerra C, Wright JF, McDonnell JW, High KA, Bennett J, Auricchio A | display-authors = 6 | title = Gene therapy for Leber's congenital amaurosis is safe and effective through 1.5 years after vector administration | journal = Molecular Therapy | volume = 18 | issue = 3 | pages = 643\u2013650 | date = March 2010 | pmid = 19953081 | pmc = 2839440 | doi = 10.1038/mt.2009.277 }}</ref><ref name="Cideciyan 2009">{{cite journal | vauthors = Cideciyan AV, Hauswirth WW, Aleman TS, Kaushal S, Schwartz SB, Boye SL, Windsor EA, Conlon TJ, Sumaroka A, Roman AJ, Byrne BJ, Jacobson SG | title = Vision 1 year after gene therapy for Leber's congenital amaurosis | journal = The New England Journal of Medicine | volume = 361 | issue = 7 | pages = 725\u2013727 | date = August 2009 | pmid = 19675341 | pmc = 2847775 | doi = 10.1056/NEJMc0903652 }}</ref><ref name="Bainbridge 2008">{{cite journal | vauthors = Bainbridge JW, Smith AJ, Barker SS, Robbie S, Henderson R, Balaggan K, Viswanathan A, Holder GE, Stockman A, Tyler N, Petersen-Jones S, Bhattacharya SS, Thrasher AJ, Fitzke FW, Carter BJ, Rubin GS, Moore AT, Ali RR | display-authors = 6 | title = Effect of gene therapy on visual function in Leber's congenital amaurosis | journal = The New England Journal of Medicine | volume = 358 | issue = 21 | pages = 2231\u20132239 | date = May 2008 | pmid = 18441371 | doi = 10.1056/NEJMoa0802268 }}</ref>\n\n In September researchers were able to give [[trichromatic vision]] to [[squirrel monkeys]].<ref>{{cite journal | last1 = Dolgin | first1 = E. | name-list-style = vanc | title = Colour blindness corrected by gene therapy | journal = Nature | year = 2009 | doi = 10.1038/news.2009.921 }}</ref> In November 2009, researchers halted a fatal [[genetic disorder]] called [[adrenoleukodystrophy]] in two children using a [[lentivirus]] vector to deliver a functioning version of [[ABCD1]], the gene that is mutated in the disorder.<ref name="pmid19892975">{{cite journal | vauthors = Cartier N, Hacein-Bey-Abina S, Bartholomae CC, Veres G, Schmidt M, Kutschera I, Vidaud M, Abel U, Dal-Cortivo L, Caccavelli L, Mahlaoui N, Kiermer V, Mittelstaedt D, Bellesme C, Lahlou N, Lefr\u00e8re F, Blanche S, Audit M, Payen E, Leboulch P, l'Homme B, Bougn\u00e8res P, Von Kalle C, Fischer A, Cavazzana-Calvo M, Aubourg P | s2cid = 27783 | display-authors = 6 | title = Hematopoietic stem cell gene therapy with a lentiviral vector in X-linked adrenoleukodystrophy | journal = Science | volume = 326 | issue = 5954 | pages = 818\u2013823 | date = November 2009 | pmid = 19892975 | doi = 10.1126/science.1171242 | bibcode = 2009Sci...326..818C }}</ref>\n\n  An April paper reported that gene therapy addressed [[achromatopsia]] (color blindness) in dogs by targeting [[Cone (vision)|cone]] photoreceptors. Cone function and day vision were restored for at least 33 months in two young specimens. The therapy was less efficient for older dogs.<ref name="Kom\u00e1romy">{{cite journal | vauthors = Kom\u00e1romy AM, Alexander JJ, Rowlan JS, Garcia MM, Chiodo VA, Kaya A, Tanaka JC, Acland GM, Hauswirth WW, Aguirre GD | display-authors = 6 | title = Gene therapy rescues cone function in congenital achromatopsia | journal = Human Molecular Genetics | volume = 19 | issue = 13 | pages = 2581\u20132593 | date = July 2010 | pmid = 20378608 | pmc = 2883338 | doi = 10.1093/hmg/ddq136 }}</ref>\n\nIn September it was announced that an 18-year-old male patient in France with [[beta-thalassemia]] major had been successfully treated.<ref>{{cite journal | vauthors = Cavazzana-Calvo M, Payen E, Negre O, Wang G, Hehir K, Fusil F, Down J, Denaro M, Brady T, Westerman K, Cavallesco R, Gillet-Legrand B, Caccavelli L, Sgarra R, Maouche-Chr\u00e9tien L, Bernaudin F, Girot R, Dorazio R, Mulder GJ, Polack A, Bank A, Soulier J, Larghero J, Kabbara N, Dalle B, Gourmel B, Socie G, Chr\u00e9tien S, Cartier N, Aubourg P, Fischer A, Cornetta K, Galacteros F, Beuzard Y, Gluckman E, Bushman F, Hacein-Bey-Abina S, Leboulch P | display-authors = 6 | title = Transfusion independence and HMGA2 activation after gene therapy of human \u03b2-thalassaemia | journal = Nature | volume = 467 | issue = 7313 | pages = 318\u2013322 | date = September 2010 | pmid = 20844535 | pmc = 3355472 | doi = 10.1038/nature09328 | bibcode = 2010Natur.467..318C }}</ref> Beta-thalassemia major is an inherited [[blood disease]] in which [[HBB|beta haemoglobin]] is missing and patients are dependent on regular lifelong [[blood transfusions]].<ref>{{cite journal | vauthors = Galanello R, Origa R | title = Beta-thalassemia | journal = Orphanet Journal of Rare Diseases | volume = 5 | pages = 11 | date = May 2010 | pmid = 20492708 | pmc = 2893117 | doi = 10.1186/1750-1172-5-11 }}</ref> The technique used a lentiviral vector to transduce the human \u03b2-globin gene into purified blood and [[Bone marrow|marrow]] cells obtained from the patient in June 2007.<ref name="medscape1">Beals, Jacquelyn K. (16 September 2010). [http://www.medscape.com/viewarticle/728656 Gene Therapy Frees Beta-Thalassemia Patient From Transfusions for 2+ Years]. Medscape.com (16 September 2010). Retrieved 15 December 2012.</ref> The patient's haemoglobin levels were stable at 9 to 10 g/dL. About a third of the hemoglobin contained the form introduced by the viral vector and blood transfusions were not needed.<ref name="medscape1"/><ref name="Leboulch">{{cite journal | vauthors = Leboulch P | date = 20 March 2013 | url = http://www.pagepressjournals.org/index.php/thal/article/view/thal.2013.s1.e43 | title = Five year outcome of lentiviral gene therapy for human beta-thalassemia, lessons and prospects | journal = Thalassemia Reports | volume =  3 | issue = 1s|page=108 | doi = 10.4081/thal.2013.s1.e43 | doi-access = free }}</ref> Further clinical trials were planned.<ref name = "NCT01639690">{{ClinicalTrialsGov|NCT01639690|\u03b2-Thalassemia Major With Autologous CD34+ Hematopoietic Progenitor Cells Transduced With TNS9.3.55 a Lentiviral Vector Encoding the Normal Human \u03b2-Globin Gene}}</ref> [[Bone marrow transplant]]s are the only cure for thalassemia, but 75% of patients do not find a matching donor.<ref name="Leboulch" />\n\nCancer immunogene therapy using modified antigene, antisense/triple helix approach was introduced in South America in 2010/11 in La Sabana University, Bogota (Ethical Committee 14 December 2010, no P-004-10). Considering the ethical aspect of gene diagnostic and gene therapy targeting IGF-I, the IGF-I expressing tumors i.e. lung and epidermis cancers were treated (Trojan et al. 2016).<ref>{{cite journal | vauthors = Trojan A, Aristizabal BH, Jay LM, Castillo T, Penagos PJ, Brice\u00f1o I, Trojan J | year = 2016| title = IGF-I biomarker testing in an ethical context | url =http://www.advmodoncolres.sg/index.php/amor/article/view/66 | journal = Adv Modern Oncol Res | volume =  2| issue = 4 | pages = 188\u2013200 | doi = 10.18282/amor.v2.i4.58 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Castillo T, Trojan A, Noguera MC, Jay LM, Crane C, Alvarez A, Kasprzak H, Melo G, Penagos PJ, Shevelev A, Aristizabal BH, Brice\u00f1o I, Ayala A, Duc HT, Trojan J | year = 2016 | title = Epistemol\u00f3gica experiencia en la elaboraci\u00f3n de tecnolog\u00eda biomolecular para estrategia de la inmunoterapia g\u00e9nica | trans-title = Epistemological experience in developing of molecular biology technology for immunogene therapy strategy | journal = Rev Cien | language = es | volume = 2 | issue = 25 | pages = 228\u2013240 | doi = 10.14483//udistrital.jour.RC.2016.25.a6 | doi-access = free }}</ref>\n\n In 2007 and 2008, a man ([[Timothy Ray Brown]]) was cured of HIV by repeated [[hematopoietic stem cell transplantation]] (see also [[allogeneic stem cell transplantation]], [[allogeneic bone marrow transplantation]], [[allotransplantation]]) with double-delta-32 mutation which disables the [[CCR5]] receptor. This cure was accepted by the medical community in 2011.<ref>Rosenberg, Tina (29 May 2011) [http://nymag.com/health/features/aids-cure-2011-6/ The Man Who Had HIV and Now Does Not], ''[[New York (magazine)|New York]]''.</ref> It required complete [[Ablation therapy|ablation]] of existing [[bone marrow]], which is very debilitating.\n\nIn August two of three subjects of a pilot study were confirmed to have been cured from [[chronic lymphocytic leukemia]] (CLL). The therapy used genetically modified [[T cells]] to attack cells that expressed the [[CD19]] protein to fight the disease.<ref name = "Porter">{{cite journal | last1 = Ledford | first1 = H. | name-list-style = vanc | title = Cell therapy fights leukaemia | journal = Nature | year = 2011 | doi = 10.1038/news.2011.472 }}</ref> In 2013, the researchers announced that 26 of 59 patients had achieved complete remission and the original patient had remained tumor-free.<ref>{{cite web|url=http://singularityhub.com/2014/01/06/gene-therapy-delivers-dramatic-success-in-treating-leukemia-will-it-work-for-other-cancers-too/ |title=Gene Therapy Turns Several Leukemia Patients Cancer Free. Will It Work for Other Cancers, Too? |publisher=Singularity Hub |access-date=7 January 2014|date=2014-01-06 }}</ref>\n\n[[Human HGF plasmid DNA therapy]] of [[cardiomyocytes]] is being examined as a potential treatment for [[coronary artery disease]] as well as treatment for the damage that occurs to the heart after [[myocardial infarction]].<ref name="YangZhang2008">{{cite journal | vauthors = Yang ZJ, Zhang YR, Chen B, Zhang SL, Jia EZ, Wang LS, Zhu TB, Li CJ, Wang H, Huang J, Cao KJ, Ma WZ, Wu B, Wang LS, Wu CT | display-authors = 6 | title = Phase I clinical trial on intracoronary administration of Ad-hHGF treating severe coronary artery disease | journal = Molecular Biology Reports | volume = 36 | issue = 6 | pages = 1323\u20131329 | date = July 2009 | pmid = 18649012 | doi = 10.1007/s11033-008-9315-3 | s2cid = 23419866 }}</ref><ref name="HahnPyun2011">{{cite journal | vauthors = Hahn W, Pyun WB, Kim DS, Yoo WS, Lee SD, Won JH, Shin GJ, Kim JM, Kim S | display-authors = 6 | title = Enhanced cardioprotective effects by coexpression of two isoforms of hepatocyte growth factor from naked plasmid DNA in a rat ischemic heart disease model | journal = The Journal of Gene Medicine | volume = 13 | issue = 10 | pages = 549\u2013555 | date = October 2011 | pmid = 21898720 | doi = 10.1002/jgm.1603 | s2cid = 26812780 }}</ref>\n\nIn 2011 [[Neovasculgen]] was registered in Russia as the first-in-class gene-therapy drug for treatment of [[peripheral artery disease]], including [[critical limb ischemia]]; it delivers the gene encoding for [[VEGF]].<ref>AdisInsight [http://adisinsight.springer.com/drugs/800041695 Vascular endothelial growth factor gene therapy \u2013 HSCI] Page accessed 5 June 2016</ref><ref name="Neuvasculgen" /> Neovasculogen is a [[plasmid]] encoding the [[Cytomegalovirus#Genetic engineering|CMV promoter]] and the 165 amino acid form of [[VEGF]].<ref>Eurolab. [http://www.eurolab.ua/medicine/drugs/5411/ Neovasculogen listing in Eurolab] Page accessed 4 August 2015</ref><ref>{{cite journal | vauthors = Deev RV, Bozo IY, Mzhavanadze ND, Voronov DA, Gavrilenko AV, Chervyakov YV, Staroverov IN, Kalinin RE, Shvalb PG, Isaev AA | display-authors = 6 | title = pCMV-vegf165 Intramuscular Gene Transfer is an Effective Method of Treatment for Patients With Chronic Lower Limb Ischemia | journal = Journal of Cardiovascular Pharmacology and Therapeutics | volume = 20 | issue = 5 | pages = 473\u2013482 | date = September 2015 | pmid = 25770117 | doi = 10.1177/1074248415574336 | s2cid = 13443907 }}</ref>\n\n The FDA approved Phase 1 clinical trials on [[thalassemia]] major patients in the US for 10 participants in July.<ref>{{cite web | url = http://www.mskcc.org/blog/launch-stem-cell-therapy-trial-offers-hope-patients-inherited-blood-disorder | title = On Cancer: Launch of Stem Cell Therapy Trial Offers Hope for Patients with Inherited Blood Disorder | publisher =  Memorial Sloan-Kettering Cancer Center | date = 16 July 2012 | access-date = 15 December 2012}}</ref> The study was expected to continue until 2015.<ref name = "NCT01639690" />\n\nIn July 2012, the [[European Medicines Agency]] recommended approval of a gene therapy treatment for the first time in either Europe or the United States. The treatment used [[Alipogene tiparvovec]] (Glybera) to compensate for [[lipoprotein lipase deficiency]], which can cause severe [[pancreatitis]].<ref>Pollack, Andrew (20 July 2012) [https://www.nytimes.com/2012/07/21/health/european-agency-recommends-approval-of-a-gene-therapy.html European Agency Backs Approval of a Gene Therapy], ''The New York Times''.</ref> The recommendation was endorsed by the [[European Commission]] in November 2012<ref name="Richards2012">{{cite web|last=Richards|first=Sabrina| name-list-style = vanc |title=Gene Therapy Arrives in Europe|url=http://www.the-scientist.com/?articles.view/articleNo/33166/title/Gene-Therapy-Arrives-in-Europe/|work=The Scientist|date=6 November 2012}}</ref><ref name="Gallagher">Gallagher, James. (2 November 2012) [https://www.bbc.co.uk/news/health-20179561 Gene therapy: Glybera approved by European Commission]. BBC News. Retrieved 15 December 2012.</ref><ref>[http://www.uniqure.com/news/167/182/uniQure-s-Glybera-First-Gene-Therapy-Approved-by-European-Commission.html First Gene Therapy Approved by European Commission] {{webarchive|url=https://web.archive.org/web/20121105033602/http://www.uniqure.com/news/167/182/uniQure-s-Glybera-First-Gene-Therapy-Approved-by-European-Commission.html |date=5 November 2012 }}. UniQure (2 November 2012). Retrieved 15 December 2012.</ref><ref>{{cite web | title = Chiesi and uniQure delay Glybera launch to add data | work = Biotechnology | publisher = [[The Pharma Letter]] | date = 4 August 2014 | url = http://www.thepharmaletter.com/article/chiesi-and-uniqure-delay-glybera-launch-to-add-data | access-date = 28 August 2014 }}</ref> and commercial rollout began in late 2014.<ref name="reuters">{{Cite news|url = https://www.reuters.com/article/us-health-genetherapy-price-idUSKCN0JA1TP20141126|title = First gene therapy drug sets million-euro price record|last1 = Burger|first1 = Ludwig| name-list-style = vanc |date = 26 November 2014|work = Reuters|access-date = 30 March 2015|last2 = Hirschler |first2 = Ben}}</ref>  Alipogene tiparvovec was expected to cost around $1.6 million per treatment in 2012,<ref>{{cite journal | journal=Wall Street Journal | first= Jeanne | last = Whalen | name-list-style = vanc | url = https://www.wsj.com/articles/SB10001424052970203707604578095091940871524 | date=2 November 2012 | title=Gene-Therapy Approval Marks Major Milestone}}</ref> revised to $1 million in 2015,<ref>{{cite journal |journal=TradeSecrets | first = Chris | last = Morrison | name-list-style = vanc | date= 3 March 2015 | title=$1-million price tag set for Glybera gene therapy}}</ref> making it the most expensive medicine in the world at the time.<ref>[http://www.bionews.org.uk/page_204696.asp Gene therapy approved in Europe for first time]</ref>  {{as of|2016}}, only the patients treated in clinical trials and a patient who paid the full price for treatment have received the drug.<ref name="MIT-TR2016">{{cite news|last1=Regalado|first1=Antonio| name-list-style = vanc |title=The World's Most Expensive Medicine Is a Bust|url=https://www.technologyreview.com/s/601165/the-worlds-most-expensive-medicine-is-a-bust/amp/|work=MIT Technology Review|date=4 May 2016}}</ref>\n\nIn December 2012, it was reported that 10 of 13 patients with [[multiple myeloma]] were in remission "or very close to it" three months after being injected with a treatment involving genetically engineered [[T cells]] to target proteins [[NY-ESO-1]] and [[LAGE-1]], which exist only on cancerous myeloma cells.<ref name="Adaptimmune" />\n\n In March researchers reported that three of five adult subjects who had [[acute lymphocytic leukemia]] (ALL) had been in remission for five months to two years after being treated with genetically modified [[T cells]] which attacked cells with [[CD19]] genes on their surface, i.e. all [[B-cells]], cancerous or not. The researchers believed that the patients' immune systems would make normal T-cells and B-cells after a couple of months. They were also given bone marrow. One patient relapsed and died and one died of a blood clot unrelated to the disease.<ref name="SloanKettering">{{cite web |vauthors=Coghlan A | date = 26 March 2013 | url = https://www.newscientist.com/article/mg21729104.100-gene-therapy-cures-leukaemia-in-eight-days.html | title = Gene therapy cures leukaemia in eight days | work = The New Scientist | access-date = 15 April 2013}}</ref>\n\nFollowing encouraging Phase 1 trials, in April, researchers announced they were starting Phase 2 clinical trials (called CUPID2 and SERCA-LVAD) on 250 patients<ref>{{cite web | last = Bosely | first = Sarah | date = 30 April 2013 | url =  https://www.theguardian.com/science/2013/apr/30/gene-therapy-trials-heart-patients | title = Pioneering gene therapy trials offer hope for heart patients | work = The Guardian | access-date = 28 April 2014 }}</ref> at several hospitals to combat [[heart disease]]. The therapy was designed to increase the levels of [[SERCA]]2, a protein in heart muscles, improving muscle function.<ref>[https://www.thephysiciansclinic.co.uk/first-gene-therapy-trial-for-heart-failure-begins-in-uk/ First gene therapy trial for heart failure begins in UK]. The Physicians Clinic (8 September 2013) {{webarchive |url=https://web.archive.org/web/20140429053945/https://www.thephysiciansclinic.co.uk/first-gene-therapy-trial-for-heart-failure-begins-in-uk/ |date=29 April 2014 }}</ref> The [[Food and Drug Administration|FDA]] granted this a [[FDA Fast Track Development Program|Breakthrough Therapy Designation]] to accelerate the trial and approval process.<ref>[http://ir.celladon.com/releasedetail.cfm?releaseid=839474 Celladon Receives Breakthrough Therapy Designation From FDA for MYDICAR(R), Novel, First-in-Class Therapy in Development to Treat Heart Failure] {{Webarchive|url=https://web.archive.org/web/20150710014412/http://ir.celladon.com/releasedetail.cfm?releaseid=839474 |date=10 July 2015 }}. New York Times (10 April 2014)</ref> In 2016 it was reported that no improvement was found from the CUPID 2 trial.<ref name="CUPID22016">{{cite journal | vauthors = Fern\u00e0ndez-Ruiz I | title = Gene therapy: No improvement in outcomes with gene therapy for heart failure | journal = Nature Reviews. Cardiology | volume = 13 | issue = 3 | pages = 122\u2013123 | date = March 2016 | pmid = 26843287 | doi = 10.1038/nrcardio.2016.14 | s2cid = 205472001 }}</ref>\n\nIn July researchers reported promising results for six children with two severe hereditary diseases had been treated with a partially deactivated lentivirus to replace a faulty gene and after 7\u201332 months. Three of the children had [[metachromatic leukodystrophy]], which causes children to lose cognitive and motor skills.<ref name="MLD">{{cite journal | vauthors = Biffi A, Montini E, Lorioli L, Cesani M, Fumagalli F, Plati T, Baldoli C, Martino S, Calabria A, Canale S, Benedicenti F, Vallanti G, Biasco L, Leo S, Kabbara N, Zanetti G, Rizzo WB, Mehta NA, Cicalese MP, Casiraghi M, Boelens JJ, Del Carro U, Dow DJ, Schmidt M, Assanelli A, Neduva V, Di Serio C, Stupka E, Gardner J, von Kalle C, Bordignon C, Ciceri F, Rovelli A, Roncarolo MG, Aiuti A, Sessa M, Naldini L | display-authors = 6 | title = Lentiviral hematopoietic stem cell gene therapy benefits metachromatic leukodystrophy | journal = Science | volume = 341 | issue = 6148 | pages = 1233158 | date = August 2013 | pmid = 23845948 | doi = 10.1126/science.1233158 | s2cid = 206546808 | url = https://zenodo.org/record/3445021 }}</ref> The other children had [[Wiskott\u2013Aldrich syndrome]], which leaves them to open to infection, autoimmune diseases, and cancer.<ref name="pmid23845947">{{cite journal | vauthors = Aiuti A, Biasco L, Scaramuzza S, Ferrua F, Cicalese MP, Baricordi C, Dionisio F, Calabria A, Giannelli S, Castiello MC, Bosticardo M, Evangelio C, Assanelli A, Casiraghi M, Di Nunzio S, Callegaro L, Benati C, Rizzardi P, Pellin D, Di Serio C, Schmidt M, Von Kalle C, Gardner J, Mehta N, Neduva V, Dow DJ, Galy A, Miniero R, Finocchi A, Metin A, Banerjee PP, Orange JS, Galimberti S, Valsecchi MG, Biffi A, Montini E, Villa A, Ciceri F, Roncarolo MG, Naldini L | display-authors = 6 | title = Lentiviral hematopoietic stem cell gene therapy in patients with Wiskott\u2013Aldrich syndrome | journal = Science | volume = 341 | issue = 6148 | pages = 1233151 | date = August 2013 | pmid = 23845947 | pmc = 4375961 | doi = 10.1126/science.1233151 }}</ref> Follow up trials with gene therapy on another six children with Wiskott\u2013Aldrich syndrome were also reported as promising.<ref>Gallagher, James (21 April 2015) [https://www.bbc.co.uk/news/health-32333161 Gene therapy: 'Tame HIV' used to cure disease] BBC News, Health, Retrieved 21 April 2015</ref><ref>{{cite journal | vauthors = Malech HL, Ochs HD | title = An emerging era of clinical benefit from gene therapy | journal = JAMA | volume = 313 | issue = 15 | pages = 1522\u20131523 | date = April 2015 | pmid = 25898049 | doi = 10.1001/jama.2015.2055 }}</ref>\n\nIn October researchers reported that two children born with [[Adenosine deaminase deficiency|adenosine deaminase severe combined immunodeficiency disease]] (ADA-SCID) had been treated with genetically engineered stem cells 18 months previously and that their immune systems were showing signs of full recovery. Another three children were making progress.<ref name="NewScientist1013" /> In 2014 a further 18 children with ADA-SCID were cured by gene therapy.<ref>[https://www.sciencedaily.com/releases/2014/11/141118141600.htm Gene therapy cure for children with 'bubble baby' disease]. ''Science Daily'' (18 November 2014)</ref> ADA-SCID children have no functioning immune system and are sometimes known as "bubble children".<ref name="NewScientist1013">Geddes, Linda (30 October 2013) [https://www.newscientist.com/article/mg22029413.200-bubble-kid-success-puts-gene-therapy-back-on-track.html#.UnUSrnC-068 'Bubble kid' success puts gene therapy back on track].  ''The New Scientist''. Retrieved 2 November 2013</ref>\n\nAlso in October researchers reported that they had treated six hemophilia sufferers in early 2011 using an adeno-associated virus. Over two years later all six were producing [[clotting factor]].<ref name="NewScientist1013" /><ref>[https://www.sciencedaily.com/releases/2014/11/141120113507.htm Gene therapy provides safe, long-term relief for patients with severe hemophilia B]. ''Science Daily'' (20 November 2014)</ref>\n\n In January researchers reported that six [[choroideremia]] patients had been treated with adeno-associated virus with a copy of [[Rab escort protein|REP1]]. Over a six-month to two-year period all had improved their sight.<ref name="pmid24439297">{{cite journal | vauthors = MacLaren RE, Groppe M, Barnard AR, Cottriall CL, Tolmachova T, Seymour L, Clark KR, During MJ, Cremers FP, Black GC, Lotery AJ, Downes SM, Webster AR, Seabra MC | title = Retinal gene therapy in patients with choroideremia: initial findings from a phase 1/2 clinical trial | journal = Lancet | volume = 383 | issue = 9923 | pages = 1129\u20131137 | date = March 2014 | pmid = 24439297 | pmc = 4171740 | doi = 10.1016/S0140-6736(13)62117-0 }}</ref><ref>Beali, Abigail (25 January 2014) [https://www.newscientist.com/article/dn24879-gene-therapy-restores-sight-in-people-with-eye-disease.html Gene therapy restores sight in people with eye disease] The New Scientist. Retrieved 25 January 2014</ref> By 2016, 32 patients had been treated with positive results and researchers were hopeful the treatment would be long-lasting.<ref name="BBC2016"/> Choroideremia is an inherited genetic eye disease with no approved treatment, leading to loss of sight.\n\nIn March researchers reported that 12 HIV patients had been treated since 2009 in a trial with a genetically engineered virus with a rare mutation ([[CCR5]] deficiency) known to protect against HIV with promising results.<ref>{{cite journal | vauthors = Tebas P, Stein D, Tang WW, Frank I, Wang SQ, Lee G, Spratt SK, Surosky RT, Giedlin MA, Nichol G, Holmes MC, Gregory PD, Ando DG, Kalos M, Collman RG, Binder-Scholl G, Plesa G, Hwang WT, Levine BL, June CH | display-authors = 6 | title = Gene editing of CCR5 in autologous CD4 T cells of persons infected with HIV | journal = The New England Journal of Medicine | volume = 370 | issue = 10 | pages = 901\u2013910 | date = March 2014 | pmid = 24597865 | pmc = 4084652 | doi = 10.1056/NEJMoa1300662 }}</ref><ref>Dvorsky, George (6 March 2014)  [http://io9.com/scientists-create-genetically-modified-cells-that-prote-1537710472 Scientists Create Genetically Modified Cells That Protect Against HIV] io9, Biotechnology. Retrieved 6 March 2014</ref>\n\nClinical trials of gene therapy for [[sickle cell disease]] were started in 2014.<ref>{{ClinicalTrialsGov|NCT02247843|Stem Cell Gene Therapy for Sickle Cell Disease}}</ref><ref>{{ClinicalTrialsGov|NCT00012545|Collection and Storage of Umbilical Cord Stem Cells for Treatment of Sickle Cell Disease}}</ref>\n\nIn February [[LentiGlobin BB305]], a gene therapy treatment undergoing clinical trials for treatment of [[beta thalassemia]] gained FDA "breakthrough" status after several patients were able to forgo the frequent blood transfusions usually required to treat the disease.<ref>{{cite news |date=3 February 2015|title=Ten things you might have missed Monday from the world of business|url=https://www.bostonglobe.com/business/2015/02/03/ten-things-you-might-have-missed-monday-from-world-business/VlQl4rdNeHZMxWlXJJcxEK/story.html|newspaper=[[Boston Globe]]|access-date=13 February 2015 }}</ref>\n\nIn March researchers delivered a [[recombinant gene]] encoding a [[broadly neutralizing antibody]] into monkeys infected with simian [[HIV/AIDS|HIV]]; the monkeys' cells produced the [[antibody]], which cleared them of HIV. The technique is named immunoprophylaxis by gene transfer (IGT). Animal tests for antibodies to ebola, malaria, influenza, and hepatitis were underway.<ref>{{cite news|title=Protection Without a Vaccine |first= Carl |last=Zimmer | name-list-style = vanc |date=9 March 2015 |work=[[The New York Times]] |access-date=30 March 2015 |url=https://www.nytimes.com/2015/03/10/health/protection-without-a-vaccine.html}}</ref><ref>{{cite journal | vauthors = Gardner MR, Kattenhorn LM, Kondur HR, von Schaewen M, Dorfman T, Chiang JJ, Haworth KG, Decker JM, Alpert MD, Bailey CC, Neale ES, Fellinger CH, Joshi VR, Fuchs SP, Martinez-Navio JM, Quinlan BD, Yao AY, Mouquet H, Gorman J, Zhang B, Poignard P, Nussenzweig MC, Burton DR, Kwong PD, Piatak M, Lifson JD, Gao G, Desrosiers RC, Evans DT, Hahn BH, Ploss A, Cannon PM, Seaman MS, Farzan M | display-authors = 6 | title = AAV-expressed eCD4-Ig provides durable protection from multiple SHIV challenges | journal = Nature | volume = 519 | issue = 7541 | pages = 87\u201391 | date = March 2015 | pmid = 25707797 | pmc = 4352131 | doi = 10.1038/nature14264 | bibcode = 2015Natur.519...87G }}</ref>\n\nIn March, scientists, including an inventor of [[CRISPR]], [[Jennifer Doudna]], urged a worldwide moratorium on germline gene therapy, writing "scientists should avoid even attempting, in lax jurisdictions, germline genome modification for clinical application in humans" until the full implications "are discussed among scientific and governmental organizations".<ref name="NYT-20150319">{{cite news |last=Wade |first=Nicholas | name-list-style = vanc |title=Scientists Seek Ban on Method of Editing the Human Genome |url=https://www.nytimes.com/2015/03/20/science/biologists-call-for-halt-to-gene-editing-technique-in-humans.html |date=19 March 2015 |work=[[The New York Times]] |access-date=20 March 2015 }}</ref><ref name="NYT-20150303-AP">{{cite news |last=Pollack |first=Andrew | name-list-style = vanc |title=A Powerful New Way to Edit DNA |url=https://www.nytimes.com/2014/03/04/health/a-powerful-new-way-to-edit-dna.html |date=3 March 2015 |work=[[The New York Times]] |access-date=20 March 2015 }}</ref><ref name="SCI-20150319">{{cite journal | vauthors = Baltimore D, Berg P, Botchan M, Carroll D, Charo RA, Church G, Corn JE, Daley GQ, Doudna JA, Fenner M, Greely HT, Jinek M, Martin GS, Penhoet E, Puck J, Sternberg SH, Weissman JS, Yamamoto KR | display-authors = 6 | title = Biotechnology. A prudent path forward for genomic engineering and germline gene modification | journal = Science | volume = 348 | issue = 6230 | pages = 36\u201338 | date = April 2015 | pmid = 25791083 | pmc = 4394183 | doi = 10.1126/science.aab1028 | bibcode = 2015Sci...348...36B }}</ref><ref name="NAT-20150312">{{cite journal | vauthors = Lanphier E, Urnov F, Haecker SE, Werner M, Smolenski J | title = Don't edit the human germ line | journal = Nature | volume = 519 | issue = 7544 | pages = 410\u2013411 | date = March 2015 | pmid = 25810189 | doi = 10.1038/519410a | bibcode = 2015Natur.519..410L | doi-access = free }}</ref>\n\nIn October, researchers announced that they had treated a baby girl, Layla Richards, with an experimental treatment using donor T-cells genetically engineered using [[Transcription activator-like effector nuclease|TALEN]] to attack cancer cells. One year after the treatment she was still free of her cancer (a highly aggressive form of [[acute lymphoblastic leukaemia]] [ALL]).<ref>{{Cite news|url=http://www.thetimes.co.uk/article/leukaemia-cure-hopes-rise-as-girl-is-gene-edited-n35md6k9s|title=Leukaemia cure hopes rise as girl is gene\u2011edited| last=Henry|first=Robin| name-list-style = vanc |date=2017-02-19|newspaper=The Times|access-date=2017-02-20|url-access=registration }}</ref> Children with highly aggressive ALL normally have a very poor prognosis and Layla's disease had been regarded as terminal before the treatment.<ref name="Layla">{{cite news|last1=Sample|first1=Ian| name-list-style = vanc |title=Baby girl is first in the world to be treated with 'designer immune cells'|url=https://www.theguardian.com/science/2015/nov/05/baby-girl-is-first-in-the-world-to-be-treated-with-designer-immune-cells|access-date=6 November 2015|newspaper=The Guardian|date=5 November 2015}}</ref>\n\nIn December, scientists of major world academies called for a moratorium on inheritable [[human genome]] edits, including those related to [[Gene drive#CRISPR/Cas9|CRISPR-Cas9]] technologies<ref name="NYT-20151203-nw">{{cite news |last=Wade |first=Nicholas |author-link=Nicholas Wade | name-list-style = vanc  |title=Scientists Place Moratorium on Edits to Human Genome That Could Be Inherited |url=https://www.nytimes.com/2015/12/04/science/crispr-cas9-human-genome-editing-moratorium.html |date=3 December 2015 |work=[[The New York Times]] |access-date=3 December 2015 }}</ref> but that basic research including embryo gene editing should continue.<ref name="BBC31Dec">{{cite news|last1=Walsh|first1=Fergus| name-list-style = vanc |title=Gene editing: Is era of designer humans getting closer?|url=https://www.bbc.co.uk/news/health-34994180|access-date=31 December 2015|publisher=BBC News Health|date=3 December 2015}}</ref>\n\n \nResearchers successfully treated a boy with [[epidermolysis bullosa]] using skin grafts grown from his own skin cells, genetically altered to repair the mutation that caused his disease.<ref>[https://www.npr.org/2017/11/08/562647401/genetically-altered-skin-saves-a-boy-dying-of-a-rare-disease Genetically Altered Skin Saves A Boy Dying Of A Rare Disease]</ref>\n\n In April the [[Committee for Medicinal Products for Human Use]] of the [[European Medicines Agency]] endorsed a gene therapy treatment called [[Strimvelis]]<ref name="StrimvelisEMA">{{cite web|title=Summary of opinion1 (initial authorisation) Strimvelis| url=http://www.ema.europa.eu/docs/en_GB/document_library/Summary_of_opinion_-_Initial_authorisation/human/003854/WC500203918.pdf| website=European Medicines Agency|access-date=13 April 2016|ref=EMA/CHMP/160482/2016|pages=1\u20132|date=1 April 2016}}</ref><ref name="Hirscheler">{{cite news|last1=Hirscheler|first1=Ben| name-list-style = vanc |title=Europe gives green light to first gene therapy for children|url=http://www.reuters.com/article/us-health-genetherapy-gsk-idUKKCN0WY4XF|access-date=13 April 2016|work=Reuters|date=1 April 2016}}</ref> and the European Commission approved it in June.<ref>{{Cite web|url=http://www.bionews.org.uk/page_656359.asp|title=Second gene therapy wins approval in Europe|last=Reeves|first=Rachel| name-list-style = vanc |date=2016-06-06|website=Bionews|access-date=2017-02-20}}</ref> This treats children born with [[adenosine deaminase deficiency]] and who have no functioning immune system. This was the second gene therapy treatment to be approved in Europe.<ref name="Strimvelis">{{cite magazine|last1=Coghlan|first1=Andy| name-list-style = vanc |title=Gene Therapy Approved|url=https://www.newscientist.com/article/2083180-gene-therapy-gets-approval-for-bubble-kids-in-world-first/|issue=3068|magazine=The New Scientist|date=9 April 2016|pages=8\u20139}}</ref>\n\nIn October, Chinese scientists reported they had started a trial to genetically modify T-cells from 10 adult patients with lung cancer and reinject the modified T-cells back into their bodies to attack the cancer cells. The T-cells had the [[Programmed cell death protein 1|PD-1 protein]] (which stops or slows the immune response) removed using CRISPR-Cas9.<ref>{{cite journal | vauthors = Cyranoski D | title = Chinese scientists to pioneer first human CRISPR trial | journal = Nature | volume = 535 | issue = 7613 | pages = 476\u2013477 | date = July 2016 | pmid = 27466105 | doi = 10.1038/nature.2016.20302 | bibcode = 2016Natur.535..476C | doi-access = free }}</ref><ref>{{cite news | first = Jay | last = Bennett | name-list-style = vanc | url = http://www.popularmechanics.com/science/health/a23898/crispr-gene-editing-tool-used-on-a-human/ | title = Chinese Scientists Become First to Use CRISPR Gene-Editing on Humans | date = 15 November 2016 | newspaper = Popular Mechanics |access-date = 16 November 2016 }}</ref>\n\nA 2016 [[Cochrane (organisation)|Cochrane systematic review]] looking at data from four trials on [[Cystic fibrosis transmembrane conductance regulator|topical cystic fibrosis transmembrane conductance regulator]] (CFTR) gene therapy does not support its clinical use as a mist inhaled into the lungs to treat cystic fibrosis patients with lung infections. One of the four trials did find weak evidence that liposome-based CFTR gene transfer therapy may lead to a small respiratory improvement for people with CF. This weak evidence is not enough to make a clinical recommendation for routine CFTR gene therapy.<ref>{{cite journal |vauthors=Lee TW, Southern KW, Perry LA, Penny-Dimri JC, Aslam AA | editor1-first = Kevin W | editor1-last = Southern | title = Topical cystic fibrosis transmembrane conductance regulator gene replacement for cystic fibrosis-related lung disease | journal = The Cochrane Database of Systematic Reviews | issue = 6 | pages = CD005599 | date = June 2016 | volume = 2016 | pmid = 27314455 | doi = 10.1002/14651858.CD005599.pub5 | pmc = 8682957 }}</ref>\n\n In February [[Kite Pharma]] announced results from a clinical trial of [[CAR-T]] cells in around a hundred people with advanced [[non-Hodgkin lymphoma]].<ref>{{Cite news|url=http://www.thetimes.co.uk/article/new-gene-therapy-offers-hope-for-cancer-patients-dl2m7zmzs|title=New gene therapy 'shrinks tumours like ice cubes'|last=Whipple|first=Tom| name-list-style = vanc |date=2017-03-01|work=The Times|access-date=2017-03-01|url-access=subscription }}</ref>\n\nIn March, French scientists reported on clinical research of gene therapy to treat [[sickle-cell disease]].<ref>{{cite news | url = https://www.newscientist.com/article/mg23331154-800-gene-therapy-breakthrough/ | title=Gene therapy 'cures' boy of blood disease that affects millions | last = Coghlan | first = Andy | name-list-style = vanc | date= March 2017 | work = New Scientist }}</ref>\n\nIn August, the FDA approved [[tisagenlecleucel]] for acute lymphoblastic leukemia.<ref>{{cite web | title = FDA approval brings first gene therapy to the United States | work = FDA News Release | publisher = U.S. Food and Drug Administration | date = 30 August 2017| url = https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm574058.htm}}</ref>  Tisagenlecleucel is an [[adoptive cell transfer]] therapy for [[B-cell]] [[acute lymphoblastic leukemia]]; [[T cells]] from a person with cancer are removed, [[genetically engineered]] to make a specific [[T-cell receptor]] (a chimeric T cell receptor, or "CAR-T") that reacts to the cancer, and are administered back to the person. The T cells are engineered to target a protein called [[CD19]] that is common on B cells. This is the first form of gene therapy to be approved in the United States. In October, a similar therapy called [[axicabtagene ciloleucel]] was approved for [[non-Hodgkin lymphoma]].<ref>{{Cite web|url=https://www.fda.gov/Drugs/InformationOnDrugs/ApprovedDrugs/ucm581296.htm|title=FDA approves axicabtagene ciloleucel for large B-cell lymphoma|last=Research|first=Center for Drug Evaluation and|website=www.fda.gov|access-date=2018-01-05}}</ref>\n\nIn October, [[Biophysics|biophysicist]] and [[Do-it-yourself biology|biohacker]] [[Josiah Zayner]] claimed to have performed the very first in-vivo human genome editing in the form of a self-administered therapy.<ref>{{Cite web|last=Zayner|first=Josiah|date=2017-10-06|title=DIY Human CRISPR Myostatin Knock-Out|url=https://www.youtube.com/watch?v=o6A9bbDI6fo&| archive-url=https://web.archive.org/web/20171111130250/https://www.youtube.com/watch?v=o6A9bbDI6fo| archive-date=2017-11-11 | url-status=dead|access-date=2020-05-20|website=Youtube}}</ref><ref>{{Cite web|last=Zayner|first=Josiah|title=The First Attempt At Human CRISPR Gene Editing|url=http://www.josiahzayner.com/2017/10/the-first-human-to-attempt-crispr-gene.html|access-date=2020-05-20}}</ref>\n\nOn November 13, medical scientists working with [[Sangamo Therapeutics]], headquartered in [[Richmond, California]], announced the first ever in-body [[human gene editing therapy]].<ref>{{Cite web|title=AP Exclusive: US scientists try 1st gene editing in the body|url=https://apnews.com/article/4ae98919b52e43d8a8960e0e260feb0a|access-date=2020-11-17|website=AP NEWS}}</ref><ref>{{Cite web|last1=KaiserNov. 15|first1=Jocelyn|last2=2017|last3=Pm|first3=6:00|date=2017-11-15|title=A human has been injected with gene-editing tools to cure his disabling disease. Here's what you need to know|url=https://www.sciencemag.org/news/2017/11/human-has-been-injected-gene-editing-tools-cure-his-disabling-disease-here-s-what-you|access-date=2020-11-17|website=Science {{!}} AAAS}}</ref>  The treatment, designed to permanently insert a healthy version of the flawed gene that causes [[Hunter syndrome]], was given to 44-year-old Brian Madeux and is part of the world's first study to permanently edit [[DNA]] inside the human body.<ref>{{Cite web|last=Zhang|first=Sarah|date=2017-11-15|title=The First Man to Have His Genes Edited Inside His Body|url=https://www.theatlantic.com/science/archive/2017/11/sangamo-first-gene-editing-in-body/545960/|access-date=2020-11-17|website=The Atlantic}}</ref>  The success of the gene insertion was later confirmed.<ref>{{Cite journal|last=Ledford|first=Heidi|date=2018-09-05|title=First test of in-body gene editing shows promise|url=https://www.nature.com/articles/d41586-018-06195-6|journal=Nature|doi=10.1038/d41586-018-06195-6|s2cid=92840885}}</ref><ref name="AP-20190207">{{cite news|last=Marchione|first=Marilyn|date=7 February 2019|title=Tests suggest scientists achieved 1st 'in body' gene editing|work=[[AP News]]|url=https://www.apnews.com/d728f86d70d94ce68dd4fedffe58d03f|access-date=7 February 2019}}</ref>  Clinical trials by Sangamo involving gene editing using [[Zinc finger nuclease|Zinc Finger Nuclease]] (ZFN) are ongoing.<ref name="CT-201902">{{cite web|author=Staff|date=2 February 2019|title=Ascending Dose Study of Genome Editing by the Zinc Finger Nuclease (ZFN) Therapeutic SB-913 in Subjects With MPS II|url=https://clinicaltrials.gov/ct2/show/NCT03041324|access-date=7 February 2019|website=[[ClinicalTrials.gov]]|publisher=[[U.S. National Library of Medicine]]}}</ref>\n\nIn December the results of using an adeno-associated virus with blood clotting [[factor VIII]] to treat nine [[haemophilia A]] patients were published. Six of the seven patients on the high dose regime increased the level of the blood clotting VIII to normal levels. The low and medium dose regimes had no effect on the patient's blood clotting levels.<ref>{{cite journal | vauthors = Rangarajan S, Walsh L, Lester W, Perry D, Madan B, Laffan M, Yu H, Vettermann C, Pierce GF, Wong WY, Pasi KJ | title = AAV5-Factor VIII Gene Transfer in Severe Hemophilia A | display-authors = 6 | journal = The New England Journal of Medicine | volume = 377 | issue = 26 | pages = 2519\u20132530 | date = December 2017 | pmid = 29224506 | doi = 10.1056/nejmoa1708483 | hdl = 10044/1/57163 | doi-access = free }}</ref><ref>{{cite journal | vauthors = van den Berg HM | title = A Cure for Hemophilia within Reach | journal = The New England Journal of Medicine | volume = 377 | issue = 26 | pages = 2592\u20132593 | date = December 2017 | pmid = 29224412 | doi = 10.1056/nejme1713888 }}</ref>\n\nIn December, the FDA approved [[Luxturna]], the first ''in vivo'' gene therapy, for the treatment of blindness due to [[Leber's congenital amaurosis]].<ref>{{Cite web|url=https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm589467.htm|title=FDA approves novel gene therapy to treat patients with a rare form of inherited vision loss|last=Office of the Commissioner|date=2017-12-19|website=FDA|access-date=2017-12-20}}</ref> The price of this treatment was 850,000 US dollars for both eyes.<ref>{{Cite news|url=https://www.forbes.com/sites/matthewherper/2018/01/03/spark-therapeutics-sets-price-of-blindness-curing-gene-therapy-at-850000/#355b36fc7dc3|title=Spark Therapeutics Sets Price Of Blindness-Treating Gene Therapy At $850,000|last=Herper|first=Matthew|date=2018-01-03|work=Forbes|access-date=2018-01-04}}</ref><ref>{{Cite news|url=http://www.newsweek.com/groundbreaking-approval-fda-signs-first-ever-gene-therapy-752711|title=The FDA approved a gene therapy to treat blindness in a groundbreaking moment for DNA-based medicine|last=Sheridan|first=Kate| name-list-style = vanc |date=2017-12-19|work=Newsweek|access-date=2017-12-20}}</ref>\n\n In May, the FDA approved [[onasemnogene abeparvovec]] (Zolgensma) for treating [[spinal muscular atrophy]] in children under two years of age. The list price of Zolgensma was set at {{US$|2.125 million}} per dose, making it the most expensive drug ever.<ref>{{cite news |last1=Stein |first1=Rob |title=At $2.1 Million, New Gene Therapy Is The Most Expensive Drug Ever |url=https://www.npr.org/sections/health-shots/2019/05/24/725404168/at-2-125-million-new-gene-therapy-is-the-most-expensive-drug-ever |access-date=24 May 2019 |work=[[NPR]] |date=24 May 2019}}</ref>\n\nIn May, the EMA approved [[betibeglogene autotemcel]] (Zynteglo) for treating [[beta thalassemia]] for people twelve years of age and older.<ref>{{cite news |last1=Tong |first1=Amber | title =EU stamps historic OK on bluebird's gene therapy for \u03b2-thalassemia \u2013 now sit back and wait for the price |url=https://endpts.com/eu-stamps-historic-ok-on-bluebirds-gene-therapy-for-%CE%B2-thalassemia-now-sit-back-and-wait-for-the-price/ | access-date=4 June 2019 |date=3 June 2019}}</ref><ref name="Zynteglo EPAR">{{cite web |title=Zynteglo EPAR |url=https://www.ema.europa.eu/en/medicines/human/EPAR/zynteglo |website=[[European Medicines Agency]] (EMA) |access-date=8 June 2020}} Text was copied from this source which is \u00a9 European Medicines Agency. Reproduction is authorized provided the source is acknowledged.</ref>\n\nIn July, [[Allergan]] and [[Editas Medicine]] announced phase 1/2 clinical trial of AGN-151587 for the treatment of [[Leber congenital amaurosis]] 10.<ref>{{cite web |title=Single Ascending Dose Study in Participants With LCA10 |url=https://clinicaltrials.gov/ct2/show/NCT03872479 |website=clinicaltrials.gov |access-date=20 August 2019 }}</ref>  This is the first study of a [[CRISPR]]-based ''[[in vivo]]'' [[human gene editing therapy]], where the editing takes place inside the human body.<ref>{{cite web |title=Allergan and Editas Medicine Initiate the Brilliance Phase 1/2 Clinical Trial of AGN-151587 (EDIT-101) for the Treatment of LCA10 |url=http://ir.editasmedicine.com/news-releases/news-release-details/allergan-and-editas-medicine-initiate-brilliance-phase-12 |website=Editas Medicine |access-date=20 August 2019 }}</ref> The first injection of the CRISPR-Cas System was confirmed in March 2020.<ref>{{Cite journal|last=Ledford|first=Heidi|date=2020-03-05|title=CRISPR treatment inserted directly into the body for first time|journal=Nature|volume=579|issue=7798|pages=185|doi=10.1038/d41586-020-00655-8|pmid=32157225|bibcode=2020Natur.579..185L|doi-access=free}}</ref>\n\n \n In May, onasemnogene abeparvovec (Zolgensma) was approved by the European Union for the treatment of spinal muscular atrophy in people who either have clinical symptoms of SMA type 1 or who have no more than 3 copies of the [[SMN2|''SMN2'' gene]], irrespective of body weight or age.<ref name="Zolgensma EPAR">{{cite web | title=Zolgensma EPAR | website=[[European Medicines Agency]] (EMA) | url=https://www.ema.europa.eu/en/medicines/human/EPAR/zolgensma | access-date=16 October 2020}}</ref>\n\nIn August, [[Astellas Pharma|Audentes Therapeutics]] reported that three out of 17 children with [[X-linked myotubular myopathy]] participating the clinical trial of a AAV8-based gene therapy treatment AT132 have died. It was suggested that the treatment, whose dosage is based on body weight, exerts a disproportionately toxic effect on heavier patients, since the three patients who died were heavier than the others.<ref>{{Cite web|date=10 August 2020|title=Audentes Therapeutics Provides Update on the ASPIRO Clinical Trial Evaluating AT132 in Patients with X-linked Myotubular Myopathy|url=https://www.audentestx.com/press_release/audentes-therapeutics-provides-update-on-the-aspiro-clinical-trial-evaluating-at132-in-patients-with-x-linked-myotubular-myopathy/|access-date=2020-09-21|website=Audentes Therapeutics}}</ref><ref>{{Cite web|title=Astellas' Audentes reports 3rd death in gene therapy trial|url=https://www.fiercebiotech.com/biotech/astellas-audentes-reports-third-death-gene-therapy-trial|access-date=2020-09-21|website=FierceBiotech}}</ref> The trial has been put on clinical hold.<ref>{{Cite journal|date=2020-08-01|title=High-dose AAV gene therapy deaths|journal=Nature Biotechnology|volume=38|issue=8|pages=910|doi=10.1038/s41587-020-0642-9|pmid=32760031|s2cid=220981004|issn=1546-1696|doi-access=free}}</ref>\n\nOn 15 October, the [[Committee for Medicinal Products for Human Use]] (CHMP) of the [[European Medicines Agency]] (EMA) adopted a positive opinion, recommending the granting of a marketing authorisation for the medicinal product [[Libmeldy]] (autologous CD34+ cell enriched population that contains hematopoietic stem and progenitor cells transduced ex vivo using a lentiviral vector encoding the human arylsulfatase A gene), a gene therapy for the treatment of children with the "late infantile" (LI) or "early juvenile" (EJ) forms of metachromatic leukodystrophy (MLD).<ref name="Libmeldy: Pending EC decision">{{cite web | title=Libmeldy: Pending EC decision | website=[[European Medicines Agency]] (EMA) | date=16 October 2020 | url=https://www.ema.europa.eu/en/medicines/human/summaries-opinion/libmeldy | access-date=16 October 2020}} Text was copied from this source which is \u00a9 European Medicines Agency. Reproduction is authorized provided the source is acknowledged.</ref> The active substance of Libmeldy consists of the child's own stem cells which have been modified to contain working copies of the ARSA gene.<ref name="Libmeldy: Pending EC decision" /> When the modified cells are injected back into the patient as a one-time infusion, the cells are expected to start producing the ARSA enzyme that breaks down the build-up of sulfatides in the nerve cells and other cells of the patient's body.<ref name="EMA PR">{{cite web|date=16 October 2020|title=New gene therapy to treat rare genetic disorder metachromatic leukodystrophy|url=https://www.ema.europa.eu/en/news/new-gene-therapy-treat-rare-genetic-disorder-metachromatic-leukodystrophy|access-date=16 October 2020|website=European Medicines Agency}} Text was copied from this source which is \u00a9 European Medicines Agency. Reproduction is authorized provided the source is acknowledged.</ref> Libmeldy was approved for medical use in the EU in December 2020.<ref name="Libmeldy EPAR">{{cite web | title=Libmeldy EPAR | website=[[European Medicines Agency]] (EMA) | url=https://www.ema.europa.eu/en/medicines/human/EPAR/libmeldy | access-date=22 December 2020}}</ref>\n\nOn 15 October, Lysogene, a French biotechnological company, reported the death of a patient in who has received LYS-SAF302, an experimental gene therapy treatment for [[Sanfilippo syndrome|mucopolysaccharidosis type IIIA]] (Sanfilippo syndrome type A).<ref>{{Cite web|last=Lysogene|title=Lysogene provides update on the AAVance Clinical Trial Evaluating LYS-SAF302 in Patients with MPS IIIA \u2013 Lysogene|date=15 October 2020|url=https://www.lysogene.com/lysogene-provides-update-on-the-aavance-clinical-trial-evaluating-lys-saf302-in-patients-with-mps-iiia/|access-date=2020-10-17}}</ref>\n\n \nIn May a new method using an altered version of the [[HIV]] virus as a [[Viral vector#Lentiviruses|lentivirus vector]] was reported in the treatment of 50 children with ADA-SCID obtaining positive results in 48 of them,<ref>{{Cite journal|last1=Kohn|first1=Donald B.|last2=Booth|first2=Claire|last3=Shaw|first3=Kit L.|last4=Xu-Bayford|first4=Jinhua|last5=Garabedian|first5=Elizabeth|last6=Trevisan|first6=Valentina|last7=Carbonaro-Sarracino|first7=Denise A.|last8=Soni|first8=Kajal|last9=Terrazas|first9=Dayna|last10=Snell|first10=Katie|last11=Ikeda|first11=Alan|date=2021-05-27|title=Autologous Ex Vivo Lentiviral Gene Therapy for Adenosine Deaminase Deficiency|url=https://doi.org/10.1056/NEJMoa2027675|journal=New England Journal of Medicine|volume=384|issue=21|pages=2002\u20132013|doi=10.1056/NEJMoa2027675|issn=0028-4793|pmc=8240285|pmid=33974366}}</ref><ref>{{Cite web|last=says|first=Chris|date=2021-05-11|title=AIDS virus used in gene therapy to fix 'bubble baby' disease|url=https://www.statnews.com/2021/05/11/aids-virus-used-in-gene-therapy-to-fix-bubble-baby-disease/|access-date=2021-07-19|website=STAT|language=en-US}}</ref><ref>{{Cite web|date=2021-05-11|title=Gene therapy restores immune function in children with rare immunodeficiency|url=https://www.nih.gov/news-events/news-releases/gene-therapy-restores-immune-function-children-rare-immunodeficiency|access-date=2021-07-19|website=National Institutes of Health (NIH)|language=EN}}</ref> this method is expected to be safer than [[Viral vector#Retroviruses|retroviruses vectors]] commonly used in previous studies of SCID where the development of [[leukemia]] was usually observed<ref>{{Cite web|title=Why Gene Therapy Caused Leukemia In Some 'Boy In The Bubble Syndrome' Patients|url=https://www.sciencedaily.com/releases/2008/08/080807175438.htm|access-date=2021-07-19|website=ScienceDaily|language=en}}</ref> and had already been used in 2019 but in a smaller group with X-SCID.<ref>{{Cite journal|last1=Mamcarz|first1=Ewelina|last2=Zhou|first2=Sheng|last3=Lockey|first3=Timothy|last4=Abdelsamed|first4=Hossam|last5=Cross|first5=Shane J.|last6=Kang|first6=Guolian|last7=Ma|first7=Zhijun|last8=Condori|first8=Jose|last9=Dowdy|first9=Jola|last10=Triplett|first10=Brandon|last11=Li|first11=Chen|date=2019-04-18|title=Lentiviral Gene Therapy Combined with Low-Dose Busulfan in Infants with SCID-X1|url=https://doi.org/10.1056/NEJMoa1815408|journal=New England Journal of Medicine|volume=380|issue=16|pages=1525\u20131534|doi=10.1056/NEJMoa1815408|issn=0028-4793|pmc=6636624|pmid=30995372}}</ref><ref>{{Cite news|date=2019-04-17|title=HIV used to cure 'bubble boy' disease|language=en-GB|work=BBC News|url=https://www.bbc.com/news/world-us-canada-47969367|access-date=2021-07-19}}</ref><ref>{{Cite web|last=Pittman|first=Jessica Ravitz,John David|title=These Scientists May Have Found a Cure for 'Bubble Boy' Disease|url=https://www.smithsonianmag.com/science-nature/scientists-found-cure-bubble-boy-disease-180973496/|access-date=2021-07-19|website=Smithsonian Magazine|language=en}}</ref><ref name=":02">{{Cite web|last=Rohr|first=Karen|date=2019-04-17|title=Gene therapy restores immunity in infants with rare immunodeficiency disease|url=https://www.nih.gov/news-events/news-releases/gene-therapy-restores-immunity-infants-rare-immunodeficiency-disease|access-date=2020-06-04|website=National Institutes of Health (NIH)|language=EN}}</ref>\n\nIn June a clinical trial on six patients affected with [[Familial amyloid polyneuropathy|transthyretin amyloidosis]] reported a reduction the concentration of missfolded [[Transthyretin|transthretin]] (TTR) protein in serum through [[CRISPR gene editing|CRISPR]]-based inactivation of the ''TTR'' gene in liver cells observing mean reductions of 52 % and 87 % among the lower and higher dose groups.This was done in vivo without taking cells out of the patient to edit them and reinfuse them later.<ref>{{Cite journal|last1=Gillmore|first1=Julian D.|last2=Gane|first2=Ed|last3=Taubel|first3=Jorg|last4=Kao|first4=Justin|last5=Fontana|first5=Marianna|last6=Maitland|first6=Michael L.|last7=Seitzer|first7=Jessica|last8=O\u2019Connell|first8=Daniel|last9=Walsh|first9=Kathryn R.|last10=Wood|first10=Kristy|last11=Phillips|first11=Jonathan|date=2021-08-05|title=CRISPR-Cas9 In Vivo Gene Editing for Transthyretin Amyloidosis|url=http://www.nejm.org/doi/10.1056/NEJMoa2107454|journal=New England Journal of Medicine|language=en|volume=385|issue=6|pages=493\u2013502|doi=10.1056/NEJMoa2107454|pmid=34215024|s2cid=235722446|issn=0028-4793}}</ref><ref>{{Cite web|title=News: Clinical Trial Update: Positive Data for First Ever In Vivo CRISPR Medicine|url=https://crisprmedicinenews.com/news/clinical-trial-update-positive-data-for-first-ever-in-vivo-crispr-medicine/|access-date=2021-12-16|website=CRISPR Medicine|language=en}}</ref><ref>{{Cite journal|date=2021-12-14|title=The science news that shaped 2021: Nature's picks|url=https://www.nature.com/articles/d41586-021-03734-6|journal=Nature|language=en|doi=10.1038/d41586-021-03734-6|pmid=34907370|s2cid=245144020}}</ref>\n\nIn July results of a small gene therapy [[Phases of clinical research#Phase I|phase 1]] study was published reporting observation of dopamine restoration on seven patients between 4 and 9 years old affected by [[aromatic L-amino acid decarboxylase deficiency]] (AADC deficiency).<ref>{{Cite journal|last1=Pearson|first1=Toni S.|last2=Gupta|first2=Nalin|last3=San Sebastian|first3=Waldy|last4=Imamura-Ching|first4=Jill|last5=Viehoever|first5=Amy|last6=Grijalvo-Perez|first6=Ana|last7=Fay|first7=Alex J.|last8=Seth|first8=Neha|last9=Lundy|first9=Shannon M.|last10=Seo|first10=Youngho|last11=Pampaloni|first11=Miguel|date=2021-07-12|title=Gene therapy for aromatic L-amino acid decarboxylase deficiency by MR-guided direct delivery of AAV2-AADC to midbrain dopaminergic neurons|journal=Nature Communications|language=en|volume=12|issue=1|pages=4251|doi=10.1038/s41467-021-24524-8|pmid=34253733|issn=2041-1723|pmc=8275582|bibcode=2021NatCo..12.4251P}}</ref><ref>{{Cite web|last1=IbrahimJul. 14|first1=Mennatalla|last2=2021|last3=Pm|first3=12:55|date=2021-07-14|title=Gene therapy restores missing dopamine in children with rare brain disease|url=https://www.sciencemag.org/news/2021/07/gene-therapy-restores-missing-dopamine-children-rare-brain-disease|access-date=2021-07-18|website=Science {{!}} AAAS|language=en}}</ref><ref>{{Cite web|date=2021-07-12|title=Gene therapy trial points to a wider window to alter course of rare disease|url=https://www.statnews.com/2021/07/12/gene-therapy-aadc-deficiency/|access-date=2021-07-18|website=STAT|language=en-US}}</ref>"}},
{"article_title": "Hydrogen", "pageid": "13255", "revid": "1062022793", "timestamp": "2021-12-25T18:23:49Z", "history_paths": [["Hydrogen --- Introduction ---", "History"]], "categories": ["hydrogen", "chemical elements", "reactive nonmetals", "diatomic nonmetals", "biology and pharmacology of chemical elements", "nuclear fusion fuels", "airship technology", "reducing agents", "refrigerants", "gaseous signaling molecules", "e-number additives"], "heading_tree": {"Hydrogen --- Introduction ---": {"Properties": {"Combustion": {"Flame": {}, "Reactants": {}}, "Electron energy levels": {}, "Spin isomers": {}, "Phases": {}, "Compounds": {"Covalent and organic compounds": {}, "Hydrides": {}, "Protons and acids": {}}, "Isotopes": {}}, "History": {"Discovery and use": {}, "Role in quantum theory": {}}, "Cosmic prevalence and distribution": {"States": {}}, "Production": {"Electrolysis of water": {}, "Methane pyrolysis (industrial method)": {}, "Industrial methods": {}, "Metal-acid": {}, "Thermochemical": {}, "Serpentinization reaction": {}}, "Applications": {"Petrochemical industry": {}, "Hydrogenation": {}, "Coolant": {}, "Energy carrier": {}, "Semiconductor industry": {}, "Rocket propellant": {}, "Niche and evolving uses": {}}, "Biological reactions": {}, "Safety and precautions": {}, "Notes": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Hydrogen --- Introduction ---|History": "{{Main|Timeline of hydrogen technologies}}\nIn 1671, [[Robert Boyle]] discovered and described the reaction between [[iron]] filings and dilute [[acid]]s, which results in the production of hydrogen gas.<ref>Boyle, R. (1672). "Tracts written by the Honourable Robert Boyle containing new experiments, touching the relation betwixt flame and air..." London.</ref><ref>{{cite web\n|first=M.\n|last=Winter\n|date=2007\n|url=http://education.jlab.org/itselemental/ele001.html\n|title=Hydrogen: historical information\n|publisher=WebElements Ltd\n|access-date=5 February 2008\n|archive-url=https://web.archive.org/web/20080410102154/http://education.jlab.org/itselemental/ele001.html\n|archive-date=10 April 2008\n|url-status=dead\n}}</ref> In 1766, [[Henry Cavendish]] was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a [[metal-acid reaction]] "inflammable air". He speculated that "inflammable air" was in fact identical to the hypothetical substance called "[[Phlogiston theory|phlogiston]]"<ref>{{cite book |last        = Musgrave\n |first       = A.\n |chapter     = Why did oxygen supplant phlogiston? Research programmes in the Chemical Revolution\n |title       = Method and appraisal in the physical sciences\n |series      = The Critical Background to Modern Science, 1800\u20131905\n |editor      = Howson, C.\n |year        = 1976\n |publisher   = Cambridge University Press\n |access-date  = 22 October 2011\n |chapter-url = http://ebooks.cambridge.org/chapter.jsf?bid=CBO9780511760013&cid=CBO9780511760013A009\n |doi         = 10.1017/CBO9780511760013\n |isbn        = 9780521211109\n |url-access  = registration\n |url         = https://archive.org/details/methodappraisali0000unse\n}}</ref><ref name="cav766">{{cite journal|last1=Cavendish|first1=Henry|title=Three Papers, Containing Experiments on Factitious Air, by the Hon. Henry Cavendish, F. R. S.|journal=Philosophical Transactions|date=12 May 1766|volume=56|pages=141\u2013184|jstor=105491|bibcode=1766RSPT...56..141C|doi=10.1098/rstl.1766.0019|doi-access=free}}</ref> and further finding in 1781 that the gas produces water when burned. He is usually given credit for the discovery of hydrogen as an element.<ref name="Nostrand">{{cite encyclopedia| title=Hydrogen| encyclopedia=Van Nostrand's Encyclopedia of Chemistry| pages=797\u2013799| publisher=Wylie-Interscience| year=2005| isbn=978-0-471-61525-5}}</ref><ref name="nbb">{{cite book| last=Emsley| first=John| title=Nature's Building Blocks| publisher=Oxford University Press| year=2001| location=Oxford| pages=183\u2013191| isbn=978-0-19-850341-5}}</ref> In 1783, [[Antoine Lavoisier]] gave the element the name hydrogen (from the Greek \u1f51\u03b4\u03c1\u03bf- ''hydro'' meaning "water" and -\u03b3\u03b5\u03bd\u03ae\u03c2 ''genes'' meaning "former")<ref>{{cite book| last=Stwertka| first=Albert| title=A Guide to the Elements| url=https://archive.org/details/guidetoelements00stwe| url-access=registration| publisher=Oxford University Press| year=1996| pages=[https://archive.org/details/guidetoelements00stwe/page/16 16\u201321]| isbn=978-0-19-508083-4}}</ref> when he and [[Pierre-Simon Laplace|Laplace]] reproduced Cavendish's finding that water is produced when hydrogen is burned.<ref name="nbb" />\n[[File:Antoine-Laurent Lavoisier (by Louis Jean Desire Delaistre)RENEW.jpg|thumb|upright=0.8|Antoine-Laurent de Lavoisier]]\nLavoisier produced hydrogen for his experiments on mass conservation by reacting a flux of steam with metallic [[iron]] through an incandescent iron tube heated in a fire. Anaerobic oxidation of iron by the protons of water at high temperature can be schematically represented by the set of following reactions:\n\n:1) <chem>Fe + H2O -> FeO + H2</chem>\n\n:2) <chem>Fe + 3 H2O -> Fe2O3 + 3 H2</chem>\n\n:3) <chem>Fe + 4 H2O -> Fe3O4 + 4 H2</chem>\n\nMany metals such as [[zirconium]] undergo a similar reaction with water leading to the production of hydrogen.\n\nHydrogen was [[Liquid hydrogen|liquefied]] for the first time by [[James Dewar]] in 1898 by using [[regenerative cooling]] and his invention, the [[vacuum flask]].<ref name="nbb" /> He produced [[solid hydrogen]] the next year.<ref name="nbb" /> [[Deuterium]] was discovered in December 1931 by [[Harold Urey]], and [[tritium]] was prepared in 1934 by [[Ernest Rutherford]], [[Mark Oliphant]], and [[Paul Harteck]].<ref name="Nostrand" /> [[Heavy water]], which consists of deuterium in the place of regular hydrogen, was discovered by Urey's group in 1932.<ref name="nbb" /> [[Fran\u00e7ois Isaac de Rivaz]] built the first [[de Rivaz engine]], an internal combustion engine powered by a mixture of hydrogen and oxygen in 1806. [[Edward Daniel Clarke]] invented the hydrogen gas blowpipe in 1819. The [[D\u00f6bereiner's lamp]] and [[limelight]] were invented in 1823.<ref name="nbb" />\n\nThe first hydrogen-filled [[balloon]] was invented by [[Jacques Charles]] in 1783.<ref name="nbb" /> Hydrogen provided the lift for the first reliable form of air-travel following the 1852 invention of the first hydrogen-lifted airship by [[Henri Giffard]].<ref name="nbb" /> German count [[Ferdinand von Zeppelin]] promoted the idea of rigid airships lifted by hydrogen that later were called [[Zeppelin]]s; the first of which had its maiden flight in 1900.<ref name="nbb" /> Regularly scheduled flights started in 1910 and by the outbreak of World War I in August 1914, they had carried 35,000 passengers without a serious incident. Hydrogen-lifted airships were used as observation platforms and bombers during the war.\n\nThe first non-stop transatlantic crossing was made by the British airship ''[[R34 (airship)|R34]]'' in 1919. Regular passenger service resumed in the 1920s and the discovery of [[helium]] reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H<sub>2</sub> was used in the [[LZ 129 Hindenburg|''Hindenburg'']] airship, which was destroyed in a midair fire over [[New Jersey]] on 6 May 1937.<ref name="nbb" /> The incident was broadcast live on radio and filmed. Ignition of leaking hydrogen is widely assumed to be the cause, but later investigations pointed to the ignition of the [[aluminium|aluminized]] fabric coating by [[static electricity]]. But the damage to hydrogen's reputation as a [[lifting gas]] was already done and commercial hydrogen airship travel [[Rigid airship#Demise|ceased]]. Hydrogen is still used, in preference to non-flammable but more expensive helium, as a lifting gas for [[Weather balloon#Materials and equipment|weather balloons]].\n\nIn the same year, the first [[hydrogen-cooled turbogenerator]] went into service with gaseous hydrogen as a [[coolant]] in the rotor and the stator in 1937 at [[Dayton, Ohio|Dayton]], Ohio, by the Dayton Power & Light Co.;<ref>{{cite book|url=https://archive.org/stream/chronologicalhis00natirich/chronologicalhis00natirich_djvu.txt|title=A chronological history of electrical development from 600 B.C|author=National Electrical Manufacturers Association|year=1946|page=102|publisher=New York, N.Y., National Electrical Manufacturers Association|access-date=9 February 2016|archive-url=https://web.archive.org/web/20160304141424/http://www.archive.org/stream/chronologicalhis00natirich/chronologicalhis00natirich_djvu.txt|archive-date=4 March 2016|url-status=live}}</ref> because of the thermal conductivity and very low viscosity of hydrogen gas, thus lower drag than air, this is the most common type in its field today for large generators (typically 60 MW and bigger; smaller generators are usually [[air cooling|air-cooled]]).\n\nThe [[nickel hydrogen battery]] was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2).<ref>{{Cite journal|title=NTS-2 Nickel-Hydrogen Battery Performance 31|journal=Journal of Spacecraft and Rockets|volume=17|pages=31\u201334|doi=10.2514/3.57704|year=1980|last1=Stockel|first1=J.F|last2=j.d. Dunlop|last3=Betz|first3=F|bibcode=1980JSpRo..17...31S}}</ref> For example, the [[International Space Station|ISS]],<ref>{{cite conference|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020070612_2002115777.pdf|work=IECEC '02. 2002 37th Intersociety Energy Conversion Engineering Conference, 2002|pages=45\u201350|date=July 2002|access-date=11 November 2011|doi=10.1109/IECEC.2002.1391972|title=Validation of international space station electrical performance model via on-orbit telemetry|last1=Jannette|first1=A. G.|last2=Hojnicki|first2=J. S.|last3=McKissock|first3=D. B.|last4=Fincannon|first4=J.|last5=Kerslake|first5=T. W.|last6=Rodriguez|first6=C. D.|isbn=0-7803-7296-4|archive-url=https://web.archive.org/web/20100514100504/http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020070612_2002115777.pdf|archive-date=14 May 2010|url-status=live|hdl=2060/20020070612|hdl-access=free}}</ref> [[2001 Mars Odyssey|Mars Odyssey]]<ref>{{cite book|doi=10.1109/AERO.2002.1035418 |title=A lightweight high reliability single battery power system for interplanetary spacecraft|journal=Aerospace Conference Proceedings|date=2002|last1=Anderson|first1=P. M.|last2=Coyne|first2=J. W.|isbn=978-0-7803-7231-3|volume=5|pages=5\u20132433|s2cid=108678345}}</ref> and the [[Mars Global Surveyor]]<ref>{{cite web|url=http://www.astronautix.com/craft/marveyor.htm|title=Mars Global Surveyor|publisher=Astronautix.com|access-date=6 April 2009|url-status=dead|archive-url=https://web.archive.org/web/20090810180658/http://www.astronautix.com/craft/marveyor.htm|archive-date=10 August 2009}}</ref> are equipped with nickel-hydrogen batteries. In the dark part of its orbit, the [[Hubble Space Telescope]] is also powered by nickel-hydrogen batteries, which were finally replaced in May 2009,<ref>{{cite web|url=http://www.nasa.gov/mission_pages/hubble/servicing/SM4/main/SM4_Essentials.html|title=Hubble servicing mission 4 essentials|date=7 May 2009|editor=Lori Tyahla|access-date=19 May 2015|publisher=NASA|archive-url=https://web.archive.org/web/20150313073737/http://www.nasa.gov/mission_pages/hubble/servicing/SM4/main/SM4_Essentials.html|archive-date=13 March 2015|url-status=live}}</ref> more than 19 years after launch and 13 years beyond their design life.<ref>{{cite web|url=http://www.nasa.gov/mission_pages/hubble/servicing/series/battery_story.html|title=Extending Hubble's mission life with new batteries|date=25 November 2008|first1=Susan|last1=Hendrix|editor=Lori Tyahla|access-date=19 May 2015|publisher=NASA|archive-url=https://web.archive.org/web/20160305002850/http://www.nasa.gov/mission_pages/hubble/servicing/series/battery_story.html|archive-date=5 March 2016|url-status=live}}</ref>\n\n [[File:Emission spectrum-H.svg|upright=2.25|thumb|Hydrogen emission spectrum lines in the visible range. These are the four visible lines of the [[Balmer series]]|alt=A line spectrum showing black background with narrow lines superimposed on it: one violet, one blue, one cyan, and one red.]]\nBecause of its simple atomic structure, consisting only of a proton and an electron, the [[hydrogen atom]], together with the spectrum of light produced from it or absorbed by it, has been central to the development of the theory of [[atom]]ic structure.<ref>{{cite book\n|last=Crepeau\n|first=R.\n|title=Niels Bohr: The Atomic Model\n|journal=Great Scientific Minds\n|date=1 January 2006\n|isbn=978-1-4298-0723-4}}</ref> Furthermore, study of the corresponding simplicity of the hydrogen molecule and the corresponding cation [[H2+|{{chem|H|2|+}}]] brought understanding of the nature of the [[chemical bond]], which followed shortly after the quantum mechanical treatment of the hydrogen atom had been developed in the mid-1920s.\n\nOne of the first quantum effects to be explicitly noticed (but not understood at the time) was a Maxwell observation involving hydrogen, half a century before full [[Quantum mechanics|quantum mechanical theory]] arrived. Maxwell observed that the [[specific heat capacity]] of H<sub>2</sub> unaccountably departs from that of a [[diatomic]] gas below room temperature and begins to increasingly resemble that of a monatomic gas at cryogenic temperatures. According to quantum theory, this behavior arises from the spacing of the (quantized) rotational energy levels, which are particularly wide-spaced in H<sub>2</sub> because of its low mass. These widely spaced levels inhibit equal partition of heat energy into rotational motion in hydrogen at low temperatures. Diatomic gases composed of heavier atoms do not have such widely spaced levels and do not exhibit the same effect.<ref name="Berman">{{cite journal\n|last1=Berman|first1=R.|last2=Cooke|first2=A. H.|last3=Hill|first3=R. W.\n|title=Cryogenics|journal=Annual Review of Physical Chemistry\n|date=1956|volume=7|pages=1\u201320\n|doi=10.1146/annurev.pc.07.100156.000245|bibcode = 1956ARPC....7....1B }}</ref>\n\n[[Antihydrogen]] ({{physics particle|anti=yes|H}}) is the [[antimatter]] counterpart to hydrogen. It consists of an [[antiproton]] with a [[positron]]. Antihydrogen is the only type of antimatter atom to have been produced {{as of|2015|lc=y}}.<ref name="char15">{{cite journal|last1=Charlton|first1=Mike|last2=Van Der Werf|first2=Dirk Peter|title=Advances in antihydrogen physics|journal=Science Progress|date=1 March 2015|volume=98|issue=1|pages=34\u201362|doi=10.3184/003685015X14234978376369|pmid=25942774|s2cid=23581065}}</ref><ref name="Keller15">{{cite journal|last1=Kellerbauer|first1=Alban|title=Why Antimatter Matters|journal=European Review|date=29 January 2015|volume=23|issue=1|pages=45\u201356|doi=10.1017/S1062798714000532|s2cid=58906869|url=https://semanticscholar.org/paper/351950a5c4cbf93bc51bfdcd646ab00b2e004677|access-date=11 January 2020|archive-date=29 January 2021|archive-url=https://web.archive.org/web/20210129015717/https://www.semanticscholar.org/paper/Why-Antimatter-Matters-Kellerbauer/351950a5c4cbf93bc51bfdcd646ab00b2e004677|url-status=live}}</ref>"}},
{"article_title": "Helium", "pageid": "13256", "revid": "1061532303", "timestamp": "2021-12-22T07:11:39Z", "history_paths": [["Helium --- Introduction ---", "History"]], "categories": ["airship technology", "helium", "chemical elements", "noble gases", "quantum phases", "coolants", "nuclear reactor coolants", "diving equipment", "e-number additives"], "heading_tree": {"Helium --- Introduction ---": {"History": {"Scientific discoveries": {}, "Extraction and use": {}}, "Characteristics": {"The helium atom": {"Helium in quantum mechanics": {}, "The related stability of the helium-4 nucleus and electron shell": {}}, "Gas and plasma phases": {}, "Liquid helium": {"Helium I": {}, "Helium II": {}}, "Isotopes": {}}, "Compounds": {}, "Occurrence and production": {"Natural abundance": {}, "Modern extraction and distribution": {}, "Conservation advocates": {}}, "Applications": {"Controlled atmospheres": {}, "Gas tungsten arc welding": {}, "Minor uses": {"Industrial leak detection": {}, "Flight": {}, "Minor commercial and recreational uses": {}, "Scientific uses": {}, "Medical uses": {}}}, "As a contaminant": {}, "Inhalation and safety": {"Effects": {}, "Hazards": {}}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Helium --- Introduction ---|History": "The first evidence of helium was observed on August 18, 1868, as a bright yellow line with a [[wavelength]] of 587.49 nanometers in the [[Emission spectrum|spectrum]] of the [[chromosphere]] of the [[Sun]]. The line was detected by French astronomer [[Pierre Janssen|Jules Janssen]] during [[Solar eclipse of August 18, 1868|a total solar eclipse]] in [[Guntur]], India.<ref name="frnch">{{Cite journal|title = French astronomers in India during the 17th \u2013 19th centuries |journal = Journal of the British Astronomical Association|volume =101|issue = 2|pages = 95\u2013100|bibcode = 1991JBAA..101...95K|author = Kochhar, R. K.|date=1991}}</ref><ref name="nbb" /> This line was initially assumed to be [[sodium]]. On October 20 of the same year, English astronomer, [[Norman Lockyer]], observed a yellow line in the solar spectrum, which, he named the D<sub>3</sub> because it was near the known D<sub>1</sub> and D<sub>2</sub> [[Fraunhofer line]] lines of sodium.<ref name="Lockyer 1868">{{cite journal |last1=Lockyer |first1=J. N. |title=Notice of an observation of the spectrum of a solar prominence |journal= Proceedings of the Royal Society of London |volume=17 |date=October 1868 |pages=91\u201392 |url= https://babel.hathitrust.org/cgi/pt?id=hvd.32044106279359;view=1up;seq=109 |jstor=112357 |access-date=3 June 2018 |bibcode=1868RSPS...17...91L |doi=10.1098/rspl.1868.0011|s2cid=163097539 }}</ref><ref name="enc">{{Cite book|title= The Encyclopedia of the Chemical Elements |pages =256\u2013268 |first = Clifford A. |last=Hampel |location=New York |isbn = 978-0-442-15598-8 |date = 1968 |publisher =Van Nostrand Reinhold}}</ref> He concluded that it was caused by an element in the Sun unknown on Earth. Lockyer and English chemist [[Edward Frankland]] named the element with the Greek word for the Sun, \u1f25\u03bb\u03b9\u03bf\u03c2 (''[[helios]]'').<ref>{{OEtymD|helium}}</ref><ref>{{Cite journal |last=Thomson |first=William |date=August 3, 1871 |volume=4 |pages=261\u2013278 [268] |doi=10.1038/004261a0 |title=Inaugural Address of Sir William Thomson |journal=Nature |url=https://books.google.com/books?id=IogCAAAAIAAJ&pg=PA268 |quote=Frankland and Lockyer find the yellow prominences to give a very decided bright line not far from D, but hitherto not identified with any terrestrial flame. It seems to indicate a new substance, which they propose to call Helium |bibcode=1871Natur...4..261. |issue=92 |pmc=2070380 |access-date=February 22, 2016 |archive-url=https://web.archive.org/web/20161202011154/https://books.google.com/books?id=IogCAAAAIAAJ&pg=PA268 |archive-date=December 2, 2016 |url-status=live }}</ref>\n[[File:Helium spectrum.jpg|left|thumb|Spectral lines of helium|alt=Picture of visible spectrum with superimposed sharp yellow and blue and violet lines]]\nIn 1881, Italian physicist [[Luigi Palmieri]] detected helium on Earth for the first time through its D<sub>3</sub> spectral line, when he analyzed a material that had been [[Sublimation (phase transition)|sublimated]] during a recent eruption of [[Mount Vesuvius]].<ref name="Palmieri 1881">{{cite journal |last1=Palmieri |first1=Luigi |title=La riga dell'Helium apparsa in una recente sublimazione vesuviana |trans-title=The line of helium appeared in a recently sublimated material [from Mt.] Vesuvius. |journal=Rendiconto dell'Accademia delle Scienze Fisiche e Matematiche (Naples, Italy) |volume=20 |date=1881 |page=223 |url=https://babel.hathitrust.org/cgi/pt?id=hvd.hnl7mr;view=1up;seq=251 |access-date=1 May 2017 |quote= ''Raccolsi alcun tempo fa una sostanza amorfa di consistenza butirracea e di colore giallo sbiadato sublimata sull'orlo di una fumarola prossima alla bocca di eruzione. Saggiata questa sublimazione allo spettroscopio, ho ravvisato le righe del sodio e del potassio ed una lineare ben distinta che corrisponde esattamente alla D<sub>3</sub> che \u00e8 quella dell'Helium. Do per ora il semplice annunzio del fatto, proponendomi di ritornare sopra questo argomento, dopo di aver sottoposta la sublimazione ad una analisi chimica.'' (I collected some time ago an amorphous substance having a buttery consistency and a faded yellow color which had sublimated on the rim of a fumarole near the mouth of the eruption. Having analyzed this sublimated substance with a spectroscope, I recognized the lines of sodium and potassium and a very distinct linear line which corresponds exactly to D<sub>3</sub>, which is that of helium. For the present, I'm making a mere announcement of the fact, proposing to return to this subject after having subjected the sublimate to a chemical analysis.) |archive-url= https://web.archive.org/web/20180901111504/https://babel.hathitrust.org/cgi/pt?id=hvd.hnl7mr;view=1up;seq=251 |archive-date=1 September 2018 |url-status=live }}</ref>\n\n[[File:William Ramsay working.jpg|thumb|upright|Sir [[William Ramsay]], the discoverer of terrestrial helium]]\n[[File:Clevite sample (35321726345).jpg|thumb|left|upright|The cleveite sample from which Ramsay first purified helium<ref name="Kirk">{{cite web| last1=Kirk|first1=Wendy L.| title= Cleveite [not Clevite] and helium| url=https://blogs.ucl.ac.uk/museums/2013/01/11/cleveite-and-helium-not-clevite/| website=Museums & Collections Blog| publisher=[[University College London]]| access-date=18 August 2017|archive-url= https://web.archive.org/web/20181018054313/http://blogs.ucl.ac.uk/museums/2013/01/11/cleveite-and-helium-not-clevite/| archive-date=18 October 2018|url-status= live}}</ref>]]\nOn March 26, 1895, Scottish chemist [[William Ramsay|Sir William Ramsay]] isolated helium on Earth by treating the mineral [[cleveite]] (a variety of [[uraninite]] with at least 10% [[rare-earth elements]]) with mineral [[acid]]s. Ramsay was looking for [[argon]] but, after separating [[nitrogen]] and [[oxygen]] from the gas, liberated by [[sulfuric acid]], he noticed a bright yellow line that matched the D<sub>3</sub> line observed in the spectrum of the Sun.<ref name="enc" /><ref>{{Cite journal|title = On a Gas Showing the Spectrum of Helium, the Reputed Cause of D<sub>3</sub>, One of the Lines in the Coronal Spectrum. Preliminary Note| last = Ramsay | first= William|author-link = William Ramsay| journal = Proceedings of the Royal Society of London|volume = 58|issue = 347\u2013352|pages = 65\u201367| date = 1895|doi = 10.1098/rspl.1895.0006| bibcode = 1895RSPS...58...65R| s2cid = 129872109| url = https://zenodo.org/record/1432083|doi-access = free}}</ref><ref>{{Cite journal| title = Helium, a Gaseous Constituent of Certain Minerals. Part I|last = Ramsay | first= William|journal = Proceedings of the Royal Society of London|volume = 58| issue = 347\u2013352|pages = 81\u201389|date = 1895 |doi = 10.1098/rspl.1895.0010| bibcode = 1895RSPS...58...80R|doi-access = free}}</ref><ref>{{Cite journal |title = Helium, a Gaseous Constituent of Certain Minerals. Part II \u2013 Density|last = Ramsay | first= William| journal = Proceedings of the Royal Society of London|volume = 59|issue = 1|pages = 325\u2013330|date = 1895 |doi = 10.1098/rspl.1895.0097|bibcode = 1895RSPS...59..325R|s2cid = 96589261}}</ref> These samples were identified as helium by Lockyer and British physicist [[William Crookes]].<ref>{{Cite journal|title = On the new gas obtained from uraninite. Preliminary note, part II|author = Lockyer, J. Norman|author-link = Norman Lockyer| journal = Proceedings of the Royal Society of London|volume = 58|issue = 347\u2013352| pages = 67\u201370|date = 1895|doi = 10.1098/rspl.1895.0008|doi-access = free}}</ref><ref>See:\n* {{cite journal| last= Crookes| first= William | year= 1895 | url= https://books.google.com/books?id=YCLOAAAAMAAJ&pg=PA151 | title= The spectrum of the gas from cl\u00e8veite | journal= Chemical News and Journal of Industrial Science| volume= 71 | number= 1844 | page= 151}}\n*  {{cite journal| last= Crookes| first= William | year= 1895 | url= https://books.google.com/books?id=lSLOAAAAMAAJ&pg=PA87 | title= The spectrum of helium | journal= Chemical News and Journal of Industrial Science | volume= 72 | number= 1865 | pages=87\u201389}}</ref> It was independently isolated from cleveite, in the same year, by chemists, [[Per Teodor Cleve]] and [[Abraham Langlet]], in [[Uppsala]], Sweden, who collected enough of the gas to accurately determine its [[atomic weight]].<ref name="nbb" /><ref>{{Cite journal|title = Das Atomgewicht des Heliums|author = Langlet, N. A.|journal = Zeitschrift f\u00fcr Anorganische Chemie|volume = 10|issue = 1| pages = 289\u2013292|date = 1895|url=https://books.google.com/books?id=sHcWAAAAIAAJ&pg=PA289|doi =10.1002/zaac.18950100130|language= de}}</ref><ref>{{Cite book| chapter= Bibliography of Helium Literature|author =Weaver, E. R.| title=Industrial & Engineering Chemistry|date=1919}}</ref> Helium was also isolated by the American geochemist, [[William Francis Hillebrand]], prior to Ramsay's discovery, when he noticed unusual spectral lines while testing a sample of the mineral uraninite. Hillebrand, however, attributed the lines to nitrogen.<ref>Hillebrand (1890) [https://babel.hathitrust.org/cgi/pt?id=uc1.b2968310&view=1up&seq=511 "On the occurrence of nitrogen in uraninite and on the composition of uraninite in general,"] ''Bulletin of the U.S. Geological Survey'', no. 78, pp. 43\u201379.</ref> His letter of congratulations to Ramsay offers an interesting case of discovery, and near-discovery, in science.<ref>{{Cite book|last=Munday|first=Pat|author-link=Pat Munday|date=1999|title=Biographical entry for W.F. Hillebrand (1853\u20131925), geochemist and U.S. Bureau of Standards administrator in American National Biography|editor=John A. Garraty|editor2=Mark C. Carnes|volume=10\u201311|publisher=Oxford University Press|pages= 808\u20139; 227\u20138|title-link=American National Biography}}</ref>\n\nIn 1907, [[Ernest Rutherford]] and [[Thomas Royds]] demonstrated that [[alpha particle]]s are helium [[atomic nucleus|nuclei]], by allowing the particles to penetrate the thin, glass wall of an evacuated tube, then creating a discharge in the tube, to study the spectrum of the new gas inside.<ref>{{Cite journal| doi = 10.1080/14786440808636511| title = XXIV.Spectrum of the radium emanation| journal = Philosophical Magazine| series = series 6| volume = 16| issue = 92| pages = 313\u2013317| year = 1908| last1 = Rutherford| first1 = E.| last2 = Royds| first2 = T.| url = https://babel.hathitrust.org/cgi/pt?id=umn.31951000614205r;view=1up;seq=349}}</ref> In 1908, helium was first liquefied by Dutch physicist [[Heike Kamerlingh Onnes]] by cooling the gas to less than {{convert|5|K|C F}}.<ref>Onnes, H. Kamerlingh (1908) [https://web.archive.org/web/20180809111624/https://babel.hathitrust.org/cgi/pt?id=uva.x002433831;view=1up;seq=309 "The liquefaction of helium,"] ''Communications from the Physical Laboratory at the University of Leiden'', '''9''' (108) : 1\u201323.</ref><ref>{{Cite journal|title = Little cup of Helium, big Science |author = van Delft, Dirk |journal = Physics Today |url = http://www-lorentz.leidenuniv.nl/history/cold/VanDelftHKO_PT.pdf |pages = 36\u201342 |date = 2008 |access-date = 2008-07-20|archive-url = https://web.archive.org/web/20080625064354/http://www-lorentz.leidenuniv.nl/history/cold/VanDelftHKO_PT.pdf |archive-date = June 25, 2008|url-status=dead|bibcode = 2008PhT....61c..36V|volume = 61|doi = 10.1063/1.2897948|issue = 3}}</ref> He tried to solidify it, by further reducing the temperature, but failed, because helium does not solidify at atmospheric pressure. Onnes' student [[Willem Hendrik Keesom]] was eventually able to solidify 1 cm<sup>3</sup> of helium in 1926 by applying additional external pressure.<ref>See:\n* Preliminary notice: Keesom, W. H. (17 July 1926) Letters to the Editor: "Solidification of helium," ''Nature'', '''118''' : 81.\n* Preliminary notice: Keesom, W. H. (1926) [https://archive.org/stream/ComptesRendusAcademieDesSciences0183/ComptesRendusAcadmieDesSciences-Tome183-Juillet-dcembre1926#page/n25/mode/2up "L'h\u00e9lium solidifi\u00e9,"] {{Webarchive|url=https://web.archive.org/web/20161022075647/https://archive.org/stream/ComptesRendusAcademieDesSciences0183/ComptesRendusAcadmieDesSciences-Tome183-Juillet-dcembre1926#page/n25/mode/2up |date=2016-10-22 }} ''Comptes rendus'' ... , '''183''' : 26.\n* Keesom, W. H. (1926) "Solid Helium," ''Communications from the Physical Laboratory at the University of Leiden'', '''17''' (184) .</ref><ref>{{Cite news| title = Coldest Cold| publisher = Time Inc.| date = 1929-06-10| url = http://www.time.com/time/magazine/article/0,9171,751945,00.html| access-date = 2008-07-27| archive-url = https://web.archive.org/web/20081206015739/http://www.time.com/time/magazine/article/0,9171,751945,00.html| archive-date = 2008-12-06| url-status = dead}}</ref>\n\nIn 1913, [[Niels Bohr]] published his "trilogy"<ref name = Hoyer>{{cite book|first = Ulrich|last = Hoyer|chapter = Constitution of Atoms and Molecules|pages = 103\u2013316 (esp. pp. 116\u2013122)|title = Niels Bohr \u2013 Collected Works: Volume 2 \u2013 Work on Atomic Physics (1912\u20131917)|chapter-url = https://books.google.com/books?id=zGczmJjSO6kC&pg=PA117|editor-first = Ulrich|editor-last = Hoyer|publisher = [[North Holland Publishing Company]]|location = Amsterdam|year = 1981|isbn = 978-0720418002}}</ref><ref>{{cite book|last = Kennedy|first = P. J.|year = 1985|chapter = A Short Biography|editor1-last = French|editor1-first = A. P.|editor2-last = Kennedy|editor2-first = P. J.|title = Niels Bohr: A Centenary Volume|pages = 3\u201315|publisher = [[Harvard University Press]]|isbn = 978-0-674-62415-3|chapter-url-access = registration|chapter-url = https://archive.org/details/nielsbohrcentena00bohr}}</ref> on atomic structure that included a reconsideration of the [[Pickering\u2013Fowler series]] as central evidence in support of his [[Bohr model|model of the atom]].<ref>{{cite journal|last = Bohr|first = N.|author-link = Niels Bohr|year = 1913|title = On the constitution of atoms and molecules, part I|journal = [[Philosophical Magazine]]|volume = 26|issue = 151|pages = 1\u201325|doi = 10.1080/14786441308634955|url = http://web.ihep.su/dbserv/compas/src/bohr13/eng.pdf|access-date = 2017-12-27|archive-url = https://web.archive.org/web/20190404184145/http://web.ihep.su/dbserv/compas/src/bohr13/eng.pdf|archive-date = 2019-04-04|url-status = live|bibcode = 1913PMag...26....1B}}<br />{{cite journal|last = Bohr|first = N.|author-link = Niels Bohr|year = 1913|title = On the constitution of atoms and molecules, part II: Systems Containing Only a Single Nucleus|journal = [[Philosophical Magazine]]|volume = 26|issue = 153|pages = 476\u2013502|url = http://web.ihep.su/dbserv/compas/src/bohr13b/eng.pdf|doi = 10.1080/14786441308634993|access-date = 2017-12-27|archive-url = https://web.archive.org/web/20171215041355/http://web.ihep.su/dbserv/compas/src/bohr13b/eng.pdf|archive-date = 2017-12-15|url-status = live|bibcode = 1913PMag...26..476B}}<br />{{cite journal|last = Bohr|first = N.|author-link = Niels Bohr|year = 1913|title = On the constitution of atoms and molecules, part III: Systems containing several nuclei|journal = [[Philosophical Magazine]]|volume = 26|issue = 155|pages = 857\u2013875|doi = 10.1080/14786441308635031|url = https://zenodo.org/record/1430922|bibcode = 1913PMag...26..857B}}</ref><ref name = Robotti>{{cite journal|title = The Spectrum of \u03b6 Puppis and the Historical Evolution of Empirical Data|first = Nadia|last = Robotti|journal = [[Historical Studies in the Physical Sciences]]|volume = 14|issue = 1|year = 1983|pages = 123\u2013145|doi = 10.2307/27757527|jstor = 27757527}}</ref> This series is named for [[Edward Charles Pickering]], who in 1896 published observations of previously unknown lines in the spectrum of the star [[Zeta Puppis|\u03b6 Puppis]]<ref>{{cite journal|last = Pickering|first = E. C.|author-link = Edward Charles Pickering|journal = [[Harvard College Observatory Circular]]|volume = 12|title = Stars having peculiar spectra. New variable stars in Crux and Cygnus|pages = 1\u20132|year = 1896|bibcode = 1896HarCi..12....1P}} Also published as: {{cite journal|title = Stars having peculiar spectra. New variable stars in Crux and Cygnus|last1 = Pickering|first1 = E. C.|author-link = Edward Charles Pickering|last2 = Fleming|first2 = W. P.|author-link2 = Williamina Fleming|journal = [[Astrophysical Journal]]|volume = 4|pages = 369\u2013370|year = 1896|doi = 10.1086/140291|bibcode = 1896ApJ.....4..369P}}</ref> (these are now known to occur with [[Wolf-Rayet star|Wolf\u2013Rayet]] and other hot stars).<ref>{{cite journal|title = The relation between the Wolf\u2013Rayet stars and the planetary nebulae|first = W. H.|last = Wright|journal = [[Astrophysical Journal]]|volume = 40|pages = 466\u2013472|year = 1914|doi = 10.1086/142138|bibcode = 1914ApJ....40..466W}}</ref> Pickering attributed the observation (lines at 4551, 5411, and 10123 [[\u00c5ngstr\u00f6m|\u00c5]]) to a new form of hydrogen with half-integer transition levels.<ref>{{cite journal|title = Stars having peculiar spectra. New variable Stars in Crux and Cygnus|first = E. C.|last = Pickering|author-link = Edward Charles Pickering|year = 1897|journal = [[Astronomische Nachrichten]]|volume = 142|issue = 6|pages = 87\u201390|doi = 10.1002/asna.18971420605|bibcode = 1896AN....142...87P|url = https://zenodo.org/record/1424755|access-date = 2019-08-24|archive-url = https://web.archive.org/web/20190824143848/https://zenodo.org/record/1424755/files/article.pdf|archive-date = 2019-08-24|url-status = live}}</ref><ref>{{cite journal|title = The spectrum of zeta Puppis|last = Pickering|first = E. C.|author-link = Edward Charles Pickering|year = 1897|journal = [[Astrophysical Journal]]|volume = 5|pages = 92\u201394|doi = 10.1086/140312|bibcode = 1897ApJ.....5...92P}}</ref> In 1912, [[Alfred Fowler]]<ref>{{cite book|title = The Methodology of Scientific Research Programmes|first = Imre|last = Lakatos|author-link = Imre Lakatos|publisher = [[Cambridge University Press]]|year = 1980|isbn = 9780521280310|editor1-first = John|editor1-last = Worrall|editor2-first = Gregory|editor2-last = Currie|chapter-url = https://books.google.com/books?id=RRniFBI8Gi4C&pg=PA62|chapter = Bohr: A Research Programme Progressing on Inconsistent Foundations|pages = 55\u201368}}</ref> managed to produce similar lines from a hydrogen-helium mixture, and supported Pickering's conclusion as to their origin.<ref>{{cite journal|title = Observations of the Principal and other Series of Lines in the Spectrum of Hydrogen|first = A.|last = Fowler|author-link = Alfred Fowler|journal = [[Monthly Notices of the Royal Astronomical Society]]|volume = 73|issue = 2|year = 1912|pages = 62\u201363|doi = 10.1093/mnras/73.2.62|bibcode = 1912MNRAS..73...62F|doi-access = free}}</ref> Bohr's model does not allow for half-integer transitions (nor does quantum mechanics) and Bohr concluded that Pickering and Fowler were wrong, and instead assigned these spectral lines to ionised helium, He<sup>+</sup>.<ref>{{cite journal|title = The Spectra of Helium and Hydrogen|first = N.|last = Bohr|author-link = Niels Bohr|journal = [[Nature (journal)|Nature]]|volume = 92|issue = 2295|year = 1913|pages = 231\u2013232|doi = 10.1038/092231d0|bibcode = 1913Natur..92..231B|s2cid = 11988018|url = https://zenodo.org/record/1429570}}</ref> Fowler was initially skeptical<ref>{{cite journal|title = The Spectra of Helium and Hydrogen|first = A.|last = Fowler|author-link = Alfred Fowler|journal = [[Nature (journal)|Nature]]|volume = 92|issue = 2291|year = 1913|pages = 95\u201396|doi = 10.1038/092095b0|bibcode = 1913Natur..92...95F|s2cid = 3972599|url = https://zenodo.org/record/1429568}}</ref> but was ultimately convinced<ref>{{cite journal|title = Reply to: The Spectra of Helium and Hydrogen|first = A.|last = Fowler|author-link = Alfred Fowler|journal = [[Nature (journal)|Nature]]|volume = 92|issue = 2295|year = 1913|pages = 232\u2013233|doi=10.1038/092232a0|bibcode = 1913Natur..92..232F|s2cid = 3981817|url = https://zenodo.org/record/1429568}}</ref> that Bohr was correct,<ref name = Hoyer /> and by 1915 "spectroscopists had transferred [the Pickering\u2013Fowler series] definitively [from hydrogen] to helium."<ref name = Robotti /><ref>{{cite journal|title = The Spectra of Hydrogen and Helium|first = N.|last = Bohr|author-link = Niels Bohr|journal = [[Nature (journal)|Nature]]|volume = 95|issue = 6\u20137|pages = 6\u20137|year = 1915|doi = 10.1038/095006a0|bibcode = 1915Natur..95....6B|s2cid = 3947572|url = https://zenodo.org/record/1429597}}</ref> Bohr's theoretical work on the Pickering series had demonstrated the need for "a re-examination of problems that seemed already to have been solved within classical theories" and provided important confirmation for his atomic theory.<ref name = Robotti />\n\nIn 1938, Russian physicist [[Pyotr Leonidovich Kapitsa]] discovered that [[helium-4]] has almost no [[viscosity]] at temperatures near [[absolute zero]], a phenomenon now called [[superfluidity]].<ref>{{Cite journal|title = Viscosity of Liquid Helium below the \u03bb-Point |author = Kapitza, P. |author-link = Pyotr Leonidovich Kapitsa |journal =Nature|volume = 141|issue = 3558 |page = 74 |doi = 10.1038/141074a0 |date = 1938|bibcode = 1938Natur.141...74K |s2cid = 3997900 |doi-access = free }}</ref> This phenomenon is related to [[Bose\u2013Einstein condensation]]. In 1972, the same phenomenon was observed in [[helium-3]], but at temperatures much closer to absolute zero, by American physicists [[Douglas D. Osheroff]], [[David M. Lee]], and [[Robert Coleman Richardson|Robert C. Richardson]]. The phenomenon in helium-3 is thought to be related to pairing of helium-3 [[fermion]]s to make [[boson]]s, in analogy to [[Cooper pairs]] of electrons producing [[superconductivity]].<ref>{{Cite journal|title = Evidence for a New Phase of Solid He<sup>3</sup> |author = Osheroff, D. D. |author2 = Richardson, R. C. |author3 = Lee, D. M. |journal = Phys. Rev. Lett. |volume = 28 |issue = 14 |pages = 885\u2013888 |doi = 10.1103/PhysRevLett.28.885 |date = 1972 |bibcode=1972PhRvL..28..885O|s2cid = 89609083 |doi-access = free }}</ref>\n\n [[File:Kansas Helium Marker.jpg|thumb|Historical marker, denoting a massive helium find near [[Dexter, Kansas]]]]\nAfter an oil drilling operation in 1903 in [[Dexter, Kansas]] produced a gas geyser that would not burn, Kansas state geologist [[Erasmus Haworth]] collected samples of the escaping gas and took them back to the [[University of Kansas]] at Lawrence where, with the help of chemists [[Hamilton Cady]] and David McFarland, he discovered that the gas consisted of, by volume, 72% nitrogen, 15% [[methane]] (a [[combustible]] percentage only with sufficient oxygen), 1% [[hydrogen]], and 12% an unidentifiable gas.<ref name="nbb" /><ref>{{Cite journal|author = McFarland, D. F. |title = Composition of Gas from a Well at Dexter, Kan |volume = 19|pages = 60\u201362 |date = 1903 |journal = Transactions of the Kansas Academy of Science |doi = 10.2307/3624173|jstor = 3624173}}</ref> With further analysis, Cady and McFarland discovered that 1.84% of the gas sample was helium.<ref>{{cite web | title = Discovery of Helium in Natural Gas at the University of Kansas | website = National Historic Chemical Landmarks | publisher = American Chemical Society | url = http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/heliumnaturalgas.html | access-date = 2014-02-21 | archive-url = https://web.archive.org/web/20140226053732/http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/heliumnaturalgas.html | archive-date = 2014-02-26 | url-status = live }}</ref><ref>{{Cite journal|author = Cady, H. P. |last2=McFarland|first2=D. F.|title = Helium in Natural Gas |journal = Science |volume = 24 |issue = 611|page = 344 |doi = 10.1126/science.24.611.344 |date = 1906 |pmid = 17772798|bibcode = 1906Sci....24..344D |url=https://zenodo.org/record/1447970}}</ref> This showed that despite its overall rarity on Earth, helium was concentrated in large quantities under the [[American Great Plains]], available for extraction as a byproduct of [[natural gas]].<ref>{{Cite journal|author = Cady, H. P.|author2 = McFarland, D. F.|title = Helium in Kansas Natural Gas |journal = Transactions of the Kansas Academy of Science |volume = 20 |pages = 80\u201381 |date = 1906|doi = 10.2307/3624645|jstor = 3624645}}</ref>\n\nThis enabled the United States to become the world's leading supplier of helium. Following a suggestion by Sir [[Richard Threlfall]], the [[United States Navy]] sponsored three small experimental helium plants during World War I. The goal was to supply [[barrage balloon]]s with the non-flammable, lighter-than-air gas. A total of {{convert|5700|m3|ft3|abbr=on}} of 92% helium was produced in the program even though less than a cubic meter of the gas had previously been obtained.<ref name="enc" /> Some of this gas was used in the world's first helium-filled airship, the U.S. Navy's [[C-class blimp]] C-7, which flew its maiden voyage from [[Hampton Roads, Virginia]], to [[Bolling Field]] in Washington, D.C., on December 1, 1921,<ref>{{Cite book|editor=Emme, Eugene M. comp. |editor-link=Eugene M. Emme |title=Aeronautics and Astronautics: An American Chronology of Science and Technology in the Exploration of Space, 1915\u20131960 |date=1961 |pages=11\u201319 |chapter=Aeronautics and Astronautics Chronology, 1920\u20131924 |chapter-url=http://www.hq.nasa.gov/office/pao/History/Timeline/1920-24.html |publisher=[[NASA]] |location=Washington, D.C. }}</ref> nearly two years before the Navy's first ''rigid'' helium-filled airship, the [[Naval Aircraft Factory]]-built [[USS Shenandoah (ZR-1)|''USS Shenandoah'']], flew in September 1923.\n\nAlthough the extraction process using low-temperature [[gas liquefaction]] was not developed in time to be significant during World War I, production continued. Helium was primarily used as a [[lifting gas]] in lighter-than-air craft. During World War II, the demand increased for helium for lifting gas and for shielded arc [[welding]]. The [[helium mass spectrometer]] was also vital in the atomic bomb [[Manhattan Project]].<ref>{{Cite book|chapter=Leak Detection|last=Hilleret|first=N.|publisher=[[CERN]]|title=CERN Accelerator School, vacuum technology: proceedings: Scanticon Conference Centre, Snekersten, Denmark, 28 May \u2013 3 June 1999 |editor=S. Turner |location=Geneva, Switzerland|chapter-url=http://cdsweb.cern.ch/record/455564 |chapter-format=PDF| date=1999 |pages=203\u2013212 |quote=At the origin of the helium leak detection method was the Manhattan Project and the unprecedented leak-tightness requirements needed by the uranium enrichment plants. The required sensitivity needed for the leak checking led to the choice of a mass spectrometer designed by Dr. A.O.C. Nier tuned on the helium mass.}}</ref>\n\nThe [[government of the United States]] set up the [[National Helium Reserve]] in 1925 at [[Amarillo, Texas]], with the goal of supplying military [[airship]]s in time of war and commercial airships in peacetime.<ref name="enc" /> Because of the [[Helium Act of 1925]], which banned the export of scarce helium on which the US then had a production monopoly, together with the prohibitive cost of the gas, the [[LZ 129 Hindenburg|Hindenburg]], like all German [[Zeppelin]]s, was forced to use hydrogen as the lift gas. The helium market after World War II was depressed but the reserve was expanded in the 1950s to ensure a supply of [[liquid helium]] as a coolant to create oxygen/hydrogen [[rocket fuel]] (among other uses) during the [[Space Race]] and [[Cold War]]. Helium use in the United States in 1965 was more than eight times the peak wartime consumption.<ref>{{Cite journal| doi = 10.2307/3627447| author = Williamson, John G.| title = Energy for Kansas| journal = Transactions of the Kansas Academy of Science| volume = 71| issue = 4| pages = 432\u2013438|date =1968| jstor = 3627447}}</ref>\n\nAfter the "Helium Acts Amendments of 1960" (Public Law 86\u2013777), the [[United States Bureau of Mines|U.S. Bureau of Mines]] arranged for five private plants to recover helium from natural gas. For this ''helium conservation'' program, the Bureau built a {{convert|425|mi|km|adj=on}} pipeline from [[Bushton, Kansas]], to connect those plants with the government's partially depleted Cliffside gas field near Amarillo, Texas. This helium-nitrogen mixture was injected and stored in the Cliffside gas field until needed, at which time it was further purified.<ref>{{Cite journal|journal = Federal Register|date = 2005-10-06|volume = 70|issue = 193|page = 58464|url = http://edocket.access.gpo.gov/2005/pdf/05-20084.pdf|title = Conservation Helium Sale|access-date = 2008-07-20|archive-url = https://web.archive.org/web/20081031082452/http://edocket.access.gpo.gov/2005/pdf/05-20084.pdf|archive-date = 2008-10-31|url-status = live}}</ref>\n\nBy 1995, a billion cubic meters of the gas had been collected and the reserve was US$1.4 billion in debt, prompting the [[Congress of the United States]] in 1996 to phase out the reserve.<ref name="nbb" /><ref name="stwertka">Stwertka, Albert (1998). ''Guide to the Elements: Revised Edition''. New York; Oxford University Press, p. 24. {{ISBN|0-19-512708-0}}</ref> The resulting [[Helium Privatization Act of 1996]]<ref>{{USPL|104|273|Helium Privatization Act of 1996}}</ref> (Public Law 104\u2013273) directed the [[United States Department of the Interior]] to empty the reserve, with sales starting by 2005.<ref>{{Cite book |url = http://www.nap.edu/openbook.php?isbn=0309070384 |title = Executive Summary |publisher = nap.edu |access-date = 2008-07-20 |archive-url = https://web.archive.org/web/20080327004306/http://www.nap.edu/openbook.php?isbn=0309070384 |archive-date = 2008-03-27 |url-status = live |doi = 10.17226/9860 |year = 2000 |isbn = 978-0-309-07038-6 }}</ref>\n\nHelium produced between 1930 and 1945 was about 98.3% pure (2% nitrogen), which was adequate for airships. In 1945, a small amount of 99.9% helium was produced for welding use. By 1949, commercial quantities of Grade A 99.95% helium were available.<ref>{{Cite book|publisher=Bureau of Mines / Minerals yearbook 1949|date=1951|last1=Mullins|first1=P. V.|last2=Goodling|first2=R. M.|title=Helium|pages=599\u2013602|url=http://digicoll.library.wisc.edu/cgi-bin/EcoNatRes/EcoNatRes-idx?type=div&did=ECONATRES.MINYB1949.PVMULLINS&isize=text|access-date=2008-07-20|archive-url=https://web.archive.org/web/20081206011210/http://digicoll.library.wisc.edu/cgi-bin/EcoNatRes/EcoNatRes-idx?type=div&did=ECONATRES.MINYB1949.PVMULLINS&isize=text|archive-date=2008-12-06|url-status=live}}</ref>\n\nFor many years, the United States produced more than 90% of commercially usable helium in the world, while extraction plants in Canada, Poland, Russia, and other nations produced the remainder. In the mid-1990s, a new plant in [[Arzew]], Algeria, producing 17 million cubic meters (600 million cubic feet) began operation, with enough production to cover all of Europe's demand. Meanwhile, by 2000, the consumption of helium within the U.S. had risen to more than 15 million kg per year.<ref>{{cite web|url=http://minerals.usgs.gov/ds/2005/140/helium-use.pdf|title=Helium End User Statistic|access-date=2008-07-20|publisher=U.S. Geological Survey|archive-url=https://web.archive.org/web/20080921114913/http://minerals.usgs.gov/ds/2005/140/helium-use.pdf|archive-date=2008-09-21|url-status=live}}</ref> In 2004\u20132006, additional plants in [[Ras Laffan Industrial City|Ras Laffan]], [[Qatar]], and [[Skikda]], Algeria were built. Algeria quickly became the second leading producer of helium.<ref name="wwsupply">{{Cite journal\n |title=Challenges to the Worldwide Supply of Helium in the Next Decade |last1=Smith|first1=E. M. |last2=Goodwin|first2=T. W. |last3=Schillinger|first3=J. |journal=Advances in Cryogenic Engineering |volume=A |issue=710 |pages=119\u2013138\n |series=49\n |date=2003 |doi=10.1063/1.1774674 |url=https://semanticscholar.org/paper/ab57e13785f1a8e11f8abd290341820bb7e590e3 |bibcode=2004AIPC..710..119S|s2cid=109060534}}</ref> Through this time, both helium consumption and the costs of producing helium increased.<ref name="Kaplan2007">{{cite journal\n |last=Kaplan |first=Karen H. |date = June 2007|title=Helium shortage hampers research and industry\n |periodical=[[Physics Today]] |publisher=[[American Institute of Physics]]\n |volume=60 |issue=6 |pages=31\u201332\n |doi=10.1063/1.2754594\n|bibcode = 2007PhT....60f..31K }}</ref> From 2002 to 2007 helium prices doubled.<ref name="Basu2007">{{Cite news |last=Basu |first=Sourish |editor-last=Yam |editor-first=Philip |date=October 2007 |title=Updates: Into Thin Air |access-date=2008-08-04 |periodical=Scientific American |publisher=Scientific American, Inc. |volume=297 |issue=4 |page=18 |url=http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=E0D18FB2-3048-8A5E-104115527CB01ADB |archive-url=https://web.archive.org/web/20081206032004/http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=E0D18FB2-3048-8A5E-104115527CB01ADB |archive-date=2008-12-06 |url-status=dead }}</ref>\n\n{{as of|2012}}, the [[National Helium Reserve|United States National Helium Reserve]] accounted for 30 percent of the world's helium.<ref name="Newcomb">{{cite news|first=Tim|last=Newcomb|url=http://newsfeed.time.com/2012/08/23/theres-a-helium-shortage-on-and-its-affecting-more-than-just-balloons/|title=There's a Helium Shortage On\u2014and It's Affecting More than Just Balloons|work=Time.com|date=21 August 2012|access-date=2013-09-16|archive-url=https://web.archive.org/web/20131229061210/http://newsfeed.time.com/2012/08/23/theres-a-helium-shortage-on-and-its-affecting-more-than-just-balloons/|archive-date=29 December 2013|url-status=live}}</ref> The reserve was expected to run out of helium in 2018.<ref name="Newcomb" /> Despite that, a proposed bill in the [[United States Senate]] would allow the reserve to continue to sell the gas. Other large reserves were in the [[Hugoton Natural Gas Area|Hugoton]] in [[Kansas]], United States, and nearby gas fields of Kansas and the [[panhandles]] of [[Texas]] and [[Oklahoma]]. New helium plants were scheduled to open in 2012 in [[Qatar]], Russia, and the US state of [[Wyoming]], but they were not expected to ease the shortage.<ref name="Newcomb" />\n\nIn 2013, Qatar started up the world's largest helium unit,<ref>{{cite web |url=http://www.airliquide.com/en/qatar-start-up-of-worlds-largest-helium-unit.html |title=Air Liquide | the world leader in gases, technologies and services for Industry and Health |access-date=2015-05-25 |url-status=dead |archive-url=https://web.archive.org/web/20140914141342/http://www.airliquide.com/en/qatar-start-up-of-worlds-largest-helium-unit.html |archive-date=2014-09-14 |date=19 February 2015 }} Air Liquide Press Release.</ref> although the [[2017 Qatar diplomatic crisis]] severely affected helium production there.<ref>{{Cite news|url=https://www.washingtonpost.com/news/wonk/wp/2017/06/26/middle-east-turmoil-is-disrupting-a-vital-resource-for-nuclear-energy-space-flight-and-birthday-balloons|title=Middle East turmoil is disrupting a vital resource for nuclear energy, space flight and birthday balloons|date=26 June 2017|work=washingtonpost.com|access-date=26 June 2017|archive-url=https://web.archive.org/web/20170626211653/https://www.washingtonpost.com/news/wonk/wp/2017/06/26/middle-east-turmoil-is-disrupting-a-vital-resource-for-nuclear-energy-space-flight-and-birthday-balloons/|archive-date=26 June 2017|url-status=live}}</ref> 2014 was widely acknowledged to be a year of over-supply in the helium business, following years of renowned shortages.<ref>{{cite web |url=http://www.gasworld.com/2015-what-lies-ahead-part-1/2004706.article |url-status=live |archive-url=https://web.archive.org/web/20150117012529/http://www.gasworld.com/2015-what-lies-ahead-part-1/2004706.article |archive-date=2015-01-17 |work=Gasworld |date=25 December 2014 |title=2015 \u2013 What lies ahead? Part 1 |last=Cockerill |first=Rob |access-date=15 September 2021}}</ref> Nasdaq reported (2015) that for [[Air Products & Chemicals|Air Products]], an international corporation that sells gases for industrial use, helium volumes remain under economic pressure due to feedstock supply constraints.<ref>{{Cite web|url=https://www.nasdaq.com/article/will-air-products-apd-earnings-surprise-estimates-in-q2-analyst-blog-cm470472|title=Will Air Products' (APD) Earnings Surprise Estimates in Q2? - Analyst Blog|date=April 28, 2015|website=NASDAQ.com|access-date=August 4, 2019|archive-url=https://web.archive.org/web/20190715085145/https://www.nasdaq.com/article/will-air-products-apd-earnings-surprise-estimates-in-q2-analyst-blog-cm470472|archive-date=July 15, 2019|url-status=live}}</ref>"}},
{"article_title": "Histology", "pageid": "13570", "revid": "1053158685", "timestamp": "2021-11-02T08:05:59Z", "history_paths": [["Histology --- Introduction ---", "History"]], "categories": ["histology", "histotechnology", "staining", "histochemistry", "anatomy"], "heading_tree": {"Histology --- Introduction ---": {"Biological tissues": {"Animal tissue classification": {}, "Plant tissue classification": {}}, "Medical histology": {"Occupations": {}}, "Sample preparation": {"Fixation": {}, "Selection and trimming": {}, "Embedding": {"Paraffin wax": {}, "Other materials": {}}, "Sectioning": {}, "Staining": {"Light microscopy": {}, "Historadiography": {}, "Immunohistochemistry": {}, "Electron microscopy": {}}, "Specialized techniques": {"Cryosectioning": {}, "Ultramicrotomy": {}}, "Artifacts": {}}, "History": {}, "Future directions": {"''In vivo'' histology": {}}, "Notes": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Histology --- Introduction ---|History": "[[File:Cajal-va.jpg|thumb|300px|left|[[Santiago Ram\u00f3n y Cajal]] in his laboratory.]]\nIn the 17th century the Italian [[Marcello Malpighi]] used microscopes to study tiny biological entities; some regard him as the founder of the fields of histology and microscopic pathology.<ref name="Bracegirdle, 1977" /><ref name="Motta 1998" /> Malpighi analyzed several parts of the organs of bats, frogs and other animals under the microscope. While studying the structure of the lung, Malpighi noticed its membranous alveoli and the hair-like connections between veins and arteries, which he named capillaries. His discovery established how the oxygen breathed in enters the blood stream and serves the body.<ref name="Adelmann and Malpighi, 1966" />\n\nIn the 19th century histology was an academic discipline in its own right. The French anatomist [[Xavier Bichat]] introduced the concept of [[Tissue (biology)|tissue]] in anatomy in 1801,<ref name="Bichat, 1801" /> and the term "histology" ({{lang-de | Histologie}}), coined to denote the "study of tissues", first appeared in a book by [[August Franz Josef Karl Mayer|Karl Meyer]] in 1819.<ref name="Mayer, 1891" /><ref name="bock" /><ref name="Bracegirdle, 1977" /> Bichat described twenty-one human tissues, which can be subsumed under the four categories currently accepted by histologists.<ref name="Rather, 1978" /> The usage of illustrations in histology, deemed as useless by Bichat, was promoted by [[Jean Cruveilhier]].<ref>\n{{cite book\n | last = Meli | first = Domenico Bertoloni\n | name-list-style = vanc | year = 2017\n | title = Visualizing disease: the art and history of pathological illustrations\n | location = Chicago\n | publisher = The University of Chicago Press\n}}{{page needed|date= August 2018}}\n</ref>{{when|date=June 2019}}\n\nIn the early 1830s [[Jan Evangelista Purkyn\u011b|Purkyn\u0115]] invented a microtome with high precision.<ref name=bock/>\n\nDuring the 19th century many [[Fixation (histology)|fixation]] techniques were developed by [[Adolph Hannover]] (solutions of [[Chromate and dichromate|chromate]]s and [[chromic acid]]), [[Franz Eilhard Schulze|Franz Schulze]] and [[Max Schultze]] ([[osmic acid]]), [[Alexander Butlerov]] ([[formaldehyde]]) and [[Benedikt Stilling]] ([[Frozen section procedure|freezing]]).<ref name=bock/>\n\n[[Microscope slide#Mounting|Mounting]] techniques were developed by [[Rudolf Heidenhain]] (1824-1898), who introduced [[gum Arabic]]; [[Salomon Stricker]] (1834-1898), who advocated a mixture of wax and oil; and [[Andrew Pritchard]] (1804-1884) who, in 1832, used a gum/[[isinglass]] mixture. In the same year, [[Canada balsam]] appeared on the scene, and in 1869 [[Edwin Klebs]] (1834-1913) reported that he had for some years embedded his specimens in paraffin.<ref>{{Cite journal|last=Bock|first=Ortwin|date=2015-01-05|title=A history of the development of histology up to the end of the nineteenth century|url=http://www.labome.org/research/A-history-of-the-development-of-histology-up-to-the-end-of-the-nineteenth-century.html|journal=Research}}</ref>\n\nThe 1906 [[Nobel Prize]] in Physiology or Medicine was awarded to histologists [[Camillo Golgi]] and [[Santiago Ramon y Cajal]]. They had conflicting interpretations of the neural structure of the brain based on differing interpretations of the same images. Ram\u00f3n y Cajal won the prize for his correct theory, and Golgi for the [[silver staining|silver-staining]] [[Golgi's method|technique]] that he invented to make it possible.<ref name="NobelPrize1906" />"}},
{"article_title": "Heat engine", "pageid": "13654", "revid": "1062806702", "timestamp": "2021-12-30T17:13:34Z", "history_paths": [["Heat engine --- Introduction ---", "History"]], "categories": ["energy conversion", "engine technology", "engines", "heating, ventilation, and air conditioning", "thermodynamics"], "heading_tree": {"Heat engine --- Introduction ---": {"Overview": {}, "Examples": {"Everyday examples": {}, "Earth's heat engine": {}, "Phase-change cycles": {}, "Gas-only cycles": {}, "Liquid-only cycles": {}, "Electron cycles": {}, "Magnetic cycles": {}, "Cycles used for refrigeration": {}, "Evaporative heat engines": {}, "Mesoscopic heat engines": {}}, "Efficiency": {"Endo-reversible heat-engines": {}}, "History": {}, "Enhancements": {}, "Heat engine processes": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Heat engine --- Introduction ---|History": "{{Main|Timeline of heat engine technology}}\n{{See also|History of the internal combustion engine|History of thermodynamics}}\n\nHeat engines have been known since antiquity but were only made into useful devices at the time of the industrial revolution in the 18th century. They continue to be developed today."}},
{"article_title": "Hydropower", "pageid": "14073", "revid": "1062910567", "timestamp": "2021-12-31T03:49:09Z", "history_paths": [["Hydropower --- Introduction ---", "History"]], "categories": ["hydropower", "power station technology", "energy conversion", "hydraulic engineering", "sustainable technologies"], "heading_tree": {"Hydropower --- Introduction ---": {"History": {}, "Calculating the amount of available power": {}, "Disadvantages and limitations": {}, "Applications": {"Mechanical power": {"Watermills": {}, "Compressed air": {}}, "Electricity": {}}, "Rain power": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Hydropower --- Introduction ---|History": "[[File:\u6c34\u51fb\u9762\u7f57.jpg|thumb|left|A water piston from the ''Nongshu'' by [[Wang Zhen (inventor)|Wang Zhen]] (fl. 1290\u20131333)]]\n[[File:SaintAnthonyFalls.jpg|thumb|[[Saint Anthony Falls]], [[United States]]; hydropower was used here to mill flour.]]\n[[File: WATER-POWERED ORE MILL, TAKEN FROM SOUTH - Liberty Historic District, Water Powered Ore Mill, Route 2, Cle Elum, Liberty, Kittitas County, WA HABS WASH,19-LIB,1W-1.tif|thumb|Directly water-powered ore mill, late nineteenth century]]\n\nEvidence suggests that the fundamentals of hydropower date to [[Ancient Greece|ancient Greek civilization]].<ref name=":3">{{cite book |last1=Munoz-Hernandez |first1=German Ardul |author-link1= |last2=Mansoor |first2=Sa'ad Petrous  |author-link2= |last3=Jones |first3=Dewi Ieuan |author-link3= |date=2013 |title=Modelling and Controlling Hydropower Plants |url=https://www.springer.com/gp/book/9781447122906 |location=London |publisher=Springer London |page= |isbn=978-1-4471-2291-3}}</ref> Other evidence indicates that the waterwheel independently emerged in China around the same period.<ref name=":3" /> Evidence of [[water wheel]]s and [[watermill]]s date to the [[ancient Near East]] in the 4th century BC.<ref name="Reynolds 1983">{{cite book |last=Reynolds |first=Terry S. |author-link= |date=1983 |title=Stronger than a Hundred Men: A History of the Vertical Water Wheel |url= |location=Baltimore |publisher=Johns Hopkins University Press |isbn=0-8018-7248-0}}</ref>{{rp|14}} Moreover, evidence indicates the use of hydropower using irrigation machines to ancient civilizations such as [[Sumer]] and [[Babylonia]].<ref name=":1">{{cite book |last=Breeze |first=Paul |author-link= |date=2018 |title=Hydropower |url=https://www.sciencedirect.com/book/9780128129067/hydropower |location=Cambridge, Massachusetts |publisher=Academic Press |page= |isbn=978-0-12-812906-7}}</ref> Studies suggest that the water wheel was the initial form of water power and it was driven by either humans or animals.<ref name=":1" />\n\nIn the [[Roman Empire]], water-powered mills were described by [[Vitruvius]] by the first century BC.<ref name="Oleson2">{{cite book|last=Oleson|first=John Peter|title=Greek and Roman mechanical water-lifting devices: the history of a technology|date=30 Jun 1984|publisher=Springer|isbn=90-277-1693-5|page=373|id={{ASIN|9027716935|country=uk}}|author-link=John Peter Oleson}}</ref> The [[Barbegal mill]], located in modern-day France, had 16 water wheels processing up to 28 tons of grain per day.<ref name=":2">{{cite book|last1=Hill|first1=Donald|url=https://books.google.com/books?id=oMceAgAAQBAJ&pg=PA163|title=A History of Engineering in Classical and Medieval Times|date=2013|publisher=[[Routledge]]|isbn=9781317761570|pages=163\u2013164|author-link1=Donald Hill}}</ref> Roman waterwheels were also used for sawing marble such as the [[Hierapolis sawmill]] of the late 3rd century AD.<ref>{{cite journal |last1=Greene |first1=Kevin |date=1990 |title=Perspectives on Roman technology |url=https://www.semanticscholar.org/paper/PERSPECTIVES-ON-ROMAN-TECHNOLOGY-Greene/042c5052b73e5deedf378d822686aa83fa3255f7 |journal=Oxford Journal of Archaeology |volume=9 |issue=2 |pages=209\u2013219 |doi=10.1111/j.1468-0092.1990.tb00223.x |s2cid=109650458 |access-date=}}</ref> Such sawmills had a waterwheel that drove two crank-and-connecting rods to power two saws. It also appears in two 6th century [[Byzantine Empire|Eastern Roman]] [[saw mill]]s excavated at [[Ephesus]] and [[Gerasa]] respectively. The [[Crank (mechanism)|crank]] and connecting rod mechanism of these [[List of Roman watermills|Roman watermills]] converted the rotary motion of the waterwheel into the linear movement of the saw blades.<ref>{{cite book |last=Magnusson |first=Roberta J. |author-link= |date=2002 |title=Water Technology in the Middle Ages: Cities, Monasteries, and Waterworks after the Roman Empire |url= |location=Baltimore |publisher=Johns Hopkins University Press |page= |isbn=978-0801866265}}</ref>\n\nWater-powered trip hammers and bellows in China, during the [[Han dynasty]] (202 BC - 220 AD), were initially thought to be powered by [[Water scoop (hydropower)|water scoops]].<ref name="Reynolds 1983" />{{rp|26\u201330}} However, some historians suggested that they were powered by waterwheels. This is since it was theorized that water scoops would not have had the motive force to operate their [[blast furnace]] bellows.<ref>{{cite book |last=Lucas |first=Adam |author-link= |date=2006 |title=Wind, Water, Work: Ancient and Medieval Milling Technology |url= |location=Leiden |publisher=Brill |page=55 |isbn=}}</ref> Many texts describe the Hun waterwheel; some of the earliest ones are the ''[[Jijiupian]]'' dictionary of 40 BC, [[Yang Xiong (author)|Yang Xiong]]'s text known as the ''[[Fangyan (book)|Fangyan]]'' of 15 BC, as well as ''Xin Lun,'' written by [[Huan Tan]] about 20 AD.<ref name=":4">{{cite book |last=Needham |first=Joseph |author-link=Joseph Needham |date=1986 |title=Science and Civilisation in China, Volume 4: Physics and Physical Technology, Part 2, Mechanical Engineering |url= |location=Taipei |publisher=Cambridge University Press |page=370 |isbn=0-521-05803-1}}</ref> It was also during this time that the engineer [[Du Shi]] (c. AD 31) applied the power of [[waterwheel]]s to [[piston]]-[[bellows]] in forging cast iron.<ref name=":4" />\n\nAnother example of the early use of hydropower is seen in [[hushing]]. Hushing is the use of the power of a wave of water released from a tank in the extraction of metal ores.{{citation needed|date=April 2021}} The method was first used at the [[Dolaucothi Gold Mines]] in [[Wales]] from 75 AD onwards. This method was further developed in Spain in mines such as [[Las M\u00e9dulas]]. Hushing was also widely used in [[Great Britain|Britain]] in the [[Middle Ages|Medieval]] and later periods to extract [[lead]] and [[tin]] ores. It later evolved into [[hydraulic mining]] when used during the [[California Gold Rush]] in the 19th century.<ref>{{cite journal |last1=Nakamura |first1=Tyler, K. |last2=Singer |first2=Michael Bliss |last3=Gabet |first3=Emmanuel J. |date=2018 |title=Remains of the 19th Century: Deep storage of contaminated hydraulic mining sediment along the Lower Yuba River, California |journal=Elem Sci Anth |volume=6 |issue=1 |pages=70 |doi=10.1525/elementa.333 |doi-access=free }}</ref>\n\nThe [[Islamic Empire]] spanned a large region, mainly in Asia and Africa, along with other surrounding areas.<ref>{{cite book |last=Hoyland |first=Robert G. |author-link=Robert G. Hoyland |date=2015 |title=In God's Path: The Arab Conquests and the Creation of an Islamic Empire |url= |location=Oxford |publisher=Oxford University Press |page= |isbn=9780199916368}}</ref> During the [[Islamic Golden Age]] and the [[Arab Agricultural Revolution]] (8th\u201313th centuries), hydropower was widely used and developed. Early uses of [[tidal power]] emerged along with large hydraulic [[factory]] complexes.<ref name=":5">{{cite journal |last1=al-Hassan |first1=Ahmad Y. |date=1976 |title=Taq\u012b-al-D\u012bn and Arabic Mechanical Engineering. With the Sublime Methods of Spiritual Machines. An Arabic Manuscript of the Sixteenth Century. |url= |journal=Institute for the History of Arabic Science, University of Aleppo |volume= |issue= |pages=34\u201335 |doi= |access-date=}}</ref>A wide range of water-powered industrial mills were used in the region including [[fulling]] mills, [[gristmill]]s, [[paper mill]]s, [[Rice huller|hullers]], [[sawmill]]s, [[ship mill]]s, [[stamp mill]]s, [[steel mill]]s, [[Sugar refinery|sugar mills]], and [[tide mill]]s. By the 11th century, every province throughout the Islamic Empire had these industrial mills in operation, from [[Al-Andalus]] and [[North Africa]] to the [[Middle East]] and [[Central Asia]].<ref name="Lucas2">{{cite journal |last1=Lucas |first1=Adam Robert |date=2005 |title=Indsutrial Milling in the Ancient and Medieval Worlds: A Survey of the Evidence for an Industrial Revolution in Medieval Europe |url=https://www.jstor.org/stable/40060793 |journal=Technology and Culture |volume=46 |issue=1 |pages=1\u201330 |doi= 10.1353/tech.2005.0026|jstor=40060793 |s2cid=109564224 |access-date=}}</ref>{{rp|10}} Muslim engineers also used [[water turbine]]s while employing [[gear]]s in watermills and water-raising machines. They also pioneered the use of [[dams]] as a source of water power, used to provide additional power to watermills and water-raising machines.<ref name="Hassan2">{{cite web |url=http://www.history-science-technology.com/Articles/articles%2071.htm |title=Transfer Of Islamic Technology To The West, Part II: Transmission Of Islamic Engineering |last=al-Hassan |first=Ahmad Y. |date= |website=History of Science and Technology in Islam |publisher= |access-date= |quote= |archive-url=https://web.archive.org/web/20080218171021/http://www.history-science-technology.com/Articles/articles%2071.htm |archive-date=18 February 2008}}</ref>\n\nFurthermore, in his book, ''The Book of Knowledge of Ingenious Mechanical Devices'', the Muslim mechanical engineer, [[Al-Jazari]] (1136\u20131206) described designs for 50 devices. Many of these devices were water-powered, including clocks, a device to serve wine, and five devices to lift water from rivers or pools, where three of them are animal-powered and one can be powered by animal or water. Moreover, they included an endless belt with jugs attached, a cow-powered [[shadoof]] (a crane-like irrigation tool), and a reciprocating device with hinged valves.<ref>{{cite journal |last1=Jones |first1=Reginald Victor |date=1974 |title=The Book of Knowledge of Ingenious Mechanical Devices by Ibn al-Razzaz Al-Jazari (translated and annotated by Donald R Hill) |url=https://iopscience.iop.org/article/10.1088/0031-9112/25/10/040 |journal=Physics Bulletin |volume=25 |issue=10 |pages=474 |doi= 10.1088/0031-9112/25/10/040|access-date=}}</ref>\n[[File:Beno\u00eet Fourneyron portrait.jpg|thumb|Beno\u00eet Fourneyron, the French engineer who developed the first hydropower turbine]]\n\nIn the 19th century, French engineer [[Beno\u00eet Fourneyron|Benoit Fourneyron]] developed the first hydropower turbine. This device was implemented in the commercial plant of [[Niagara Falls]] in 1895 and it is still operating.<ref name=":1" /> In the early 20th century, English engineer [[William Armstrong, 1st Baron Armstrong|William Armstrong]] built and operated the first private electrical power station which was located in his house in [[Cragside]] in [[Northumberland]], [[England]].<ref name=":1" /> In 1753, the French engineer [[Bernard Forest de B\u00e9lidor]] published his book, ''Architecture Hydraulique'', which described vertical- and horizontal-axis hydraulic machines.<ref name="doehis">{{cite web|title=History of Hydropower|url=http://www1.eere.energy.gov/windandhydro/hydro_history.html|url-status=dead|archive-url=https://web.archive.org/web/20100126001540/http://www1.eere.energy.gov/windandhydro/hydro_history.html|archive-date=26 January 2010|publisher=US Department of Energy}}</ref>\n\nThe growing demand for the [[Industrial Revolution]] would drive development as well.<ref name="watenc">{{cite web|title=Hydroelectric Power|url=http://www.waterencyclopedia.com/Ge-Hy/Hydroelectric-Power.html|publisher=Water Encyclopedia}}</ref> At the beginning of the Industrial Revolution in Britain, water was the main power source for new inventions such as [[Richard Arkwright]]'s [[water frame]].<ref name=":6">{{cite book |last=Perkin |first=Harold James |author-link=Harold Perkin |date=1969 |title=The Origins of Modern English Society, 1780-1880 |url= |location=London |publisher=Routledge & Kegan Paul PLC |page= |isbn=9780710045676}}</ref> Although water power gave way to steam power in many of the larger mills and factories, it was still used during the 18th and 19th centuries for many smaller operations, such as driving the bellows in small [[blast furnace]]s (e.g. the [[Dyfi Furnace]]) and [[gristmill]]s, such as those built at [[Saint Anthony Falls]], which uses the 50-foot (15 m) drop in the [[Mississippi River]].{{Citation needed|date=April 2021}}<ref name=":6" />\n\nTechnological advances moved the open water wheel into an enclosed [[turbine]] or [[Water engine|water motor]]. In 1848, the British-American engineer [[James B. Francis]], head engineer of Lowell's Locks and Canals company, improved on these designs to create a turbine with 90% efficiency.<ref>{{Cite journal|last1=Lewis|first1=B J|last2=Cimbala|last3=Wouden|title=Major historical developments in the design of water wheels and Francis hydroturbines|journal=Iop Conference Series: Earth and Environmental Science|year=2014|publisher=IOP|volume=22|issue=1|pages=5\u20137|doi=10.1088/1755-1315/22/1/012020|bibcode=2014E&ES...22a2020L|doi-access=free}}</ref> He applied scientific principles and testing methods to the problem of turbine design. His mathematical and graphical calculation methods allowed the confident design of high-efficiency turbines to exactly match a site's specific flow conditions. The [[Francis turbine|Francis reaction turbine]] is still in use. In the 1870s, deriving from uses in the California mining industry, [[Lester Allan Pelton]] developed the high-efficiency [[Pelton wheel|Pelton wheel impulse turbine]], which used hydropower from the high head streams characteristic of the [[Sierra Nevada]].{{Citation needed|date=April 2021}}"}},
{"article_title": "Human cloning", "pageid": "14094", "revid": "1062404269", "timestamp": "2021-12-28T07:34:34Z", "history_paths": [["Human cloning --- Introduction ---", "History"]], "categories": ["biotechnology", "cloning"], "heading_tree": {"Human cloning --- Introduction ---": {"History": {}, "Methods": {"Somatic cell nuclear transfer (SCNT)": {}, "Induced pluripotent stem cells (iPSCs)": {}, "Comparing SCNT to reprogramming": {}}, "Uses, actual and potential": {}, "Ethical implications": {}, "Current law": {}, "In popular culture": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Human cloning --- Introduction ---|History": "Although the possibility of [[cloning]] humans had been the subject of speculation for much of the 20th century, scientists and policymakers began to take the prospect seriously in 1969. [[J. B. S. Haldane]] was the first to introduce the idea of human cloning, for which he used the terms "clone" and "cloning",<ref>{{cite book|title=Should scientists pursue cloning?|last=Thomas|first=Isabel|publisher=Raintree|year=2013|isbn=978-1-4062-3391-9|location=London|page=5}}</ref> which had been used in agriculture since the early 20th century. In his speech on "Biological Possibilities for the Human Species of the Next Ten Thousand Years" at the ''[[Ciba Foundation]] Symposium on Man and his Future'' in 1963, he said:<ref>{{cite book|title=Man and his future|author=Haldane, J.B.S.|publisher=J. & A. Churchill|year=1963|isbn=978-0-470-71479-9|editor=Wolstenholme, Gordon|series=Novartis Foundation Symposia|location=London|pages=337\u2013361|chapter=Biological Possibilities for the Human Species in the Next Ten Thousand Years|doi=10.1002/9780470715291.ch22}}</ref>\n{{Quote|It is extremely hopeful that some human cell lines can be grown on a medium of precisely known chemical composition. Perhaps the first step will be the production of a clone from a single fertilized egg, as in ''[[Brave New World]]''...\n\nAssuming that cloning is possible, I expect that most clones would be made from people aged at least fifty, except for athletes and dancers, who would be cloned younger. They would be made from people who were held to have excelled in a socially acceptable accomplishment.}}\n\nNobel Prize-winning geneticist [[Joshua Lederberg]] advocated cloning and [[genetic engineering]] in an article in ''[[The American Naturalist]]'' in 1966 and again, the following year, in ''[[The Washington Post]]''.<ref>{{cite journal | author = Lederberg Joshua | year = 1966 | title = Experimental Genetics and Human Evolution | journal = The American Naturalist | volume = 100 | issue = 915| pages = 519\u2013531 | doi=10.1086/282446| bibcode = 1966BuAtS..22h...4L | s2cid = 222323744 }}</ref> He sparked a debate with conservative bioethicist [[Leon Kass]], who wrote at the time that "the programmed reproduction of man will, in fact, dehumanize him." Another [[Nobel Prize in Physiology or Medicine|Nobel Laureate]], [[James D. Watson]], publicized the potential and the perils of cloning in his ''[[Atlantic Monthly]]'' essay, "Moving Toward the Clonal Man", in 1971.<ref>Watson, James. [https://www.theatlantic.com/magazine/archive/1971/05/moving-toward-the-clonal-man/305435/ "Moving Toward a Clonal Man: Is This What We Want?"] The Atlantic Monthly (1971).</ref>\n\nWith the cloning of a sheep known as [[Dolly (sheep)|Dolly]] in 1996 by [[somatic cell nuclear transfer]] (SCNT), the idea of human cloning became a hot debate topic.<ref name=TIME>{{cite news|title=Researchers Clone Cells From Two Adult Men|first= Alice |last= Park| date= April 17, 2014|work=Time|url=http://time.com/65610/cloning-cells-from-two-adult-men/|access-date=April 18, 2014}}</ref> Many nations outlawed it, while a few scientists promised to make a clone within the next few years. The first [[Hybrid (biology)|hybrid]] human clone was created in November 1998, by [[Advanced Cell Technology]]. It was created using SCNT; a nucleus was taken from a man's leg cell and inserted into a cow's egg from which the nucleus had been removed, and the hybrid cell was cultured and developed into an [[embryo]]. The embryo was destroyed after 12 days.<ref>{{cite news| url=http://news.bbc.co.uk/2/hi/science/nature/371378.stm | work=BBC News | title=Details of hybrid clone revealed | date=June 18, 1999 | access-date= April 30, 2010}}</ref>\n\nIn 2004 and 2005, [[Hwang Woo-suk]], a professor at [[Seoul National University]], published two separate articles in the journal [[Science (journal)|'' Science'']] claiming to have successfully harvested pluripotent, [[embryonic stem cells]] from a cloned human blastocyst using SCNT techniques. Hwang claimed to have created eleven different patient-specific stem cell lines. This would have been the first major breakthrough in human cloning.<ref>Fischbak, Ruth L., John D. Loike, Janet Mindes, and Columbia Center for New Media Teaching & Learning. [http://stemcellbioethics.wikischolars.columbia.edu/The+Cloning+Scandal+of+Hwang+Woo-Suk The Cloning Scandal of Hwang Woo-Suk], part of the online course, [http://stemcellbioethics.wikischolars.columbia.edu/ Stem Cells: Biology, Ethics, and Applications]</ref> However, in 2006 ''Science'' retracted both of his articles on clear evidence that much of his data from the experiments was fabricated.<ref name="pmid17138870">{{cite journal|author=Kennedy D|year=2006|title=Responding to fraud|journal=Science|volume=314|issue=5804|pages=1353|doi=10.1126/science.1137840|pmid=17138870|s2cid=37403975|doi-access=free}}</ref>\n\nIn January 2008, Dr. Andrew French and [[Samuel H. Wood|Samuel Wood]] of the biotechnology company [[Stemagen]] announced that they successfully created the first five mature human embryos using SCNT. In this case, each embryo was created by taking a nucleus from a skin cell (donated by Wood and a colleague) and inserting it into a human egg from which the nucleus had been removed. The embryos were developed only to the [[blastocyst]] stage, at which point they were studied in processes that destroyed them.  Members of the lab said that their next set of experiments would aim to generate embryonic stem cell lines; these are the "holy grail" that would be useful for therapeutic or reproductive cloning.<ref>, Rick Weiss for the Washington Post January 18, 2008 [https://www.washingtonpost.com/wp-dyn/content/article/2008/01/17/AR2008011700324.html?hpid=topnews Mature Human Embryos Created From Adult Skin Cells]</ref><ref name="pmid18202077">{{cite journal |last1=French |first1=Andrew J. |last2=Adams |first2=Catharine A. |last3=Anderson |first3=Linda S. |last4=Kitchen |first4=John R. |last5=Hughes |first5=Marcus R. |last6=Wood |first6=Samuel H. |title=Development of Human Cloned Blastocysts Following Somatic Cell Nuclear Transfer with Adult Fibroblasts |journal=Stem Cells |date=February 2008 |volume=26 |issue=2 |pages=485\u2013493 |doi=10.1634/stemcells.2007-0252 |pmid=18202077 |s2cid=21251761 |doi-access=free }}</ref>\n\nIn 2011, scientists at the New York Stem Cell Foundation announced that they had succeeded in generating embryonic stem cell lines, but their process involved leaving the [[oocyte]]'s nucleus in place, resulting in [[triploid]] cells, which would not be useful for cloning.<ref name=TrounsonComment/><ref name="pmid21979046">{{cite journal |vauthors=Noggle S, Fung HL, Gore A, Martinez H, Satriani KC, Prosser R, Oum K, Paull D, Druckenmiller S, Freeby M, Greenberg E, Zhang K, Goland R, Sauer MV, Leibel RL, Egli D | title = Human oocytes reprogram somatic cells to a pluripotent state | journal = Nature | volume = 478 | issue = 7367 | pages = 70\u20135 | year = 2011 | pmid = 21979046 | doi = 10.1038/nature10397 | bibcode = 2011Natur.478...70N | s2cid = 4370078 }}</ref><ref name="pmid21979039">{{cite journal |vauthors=Daley GQ, Solbakk JH | title = Stem cells: Triple genomes go far | journal = Nature | volume = 478 | issue = 7367 | pages = 40\u20131 | year = 2011 | pmid = 21979039 | doi = 10.1038/478040a | bibcode = 2011Natur.478...40D | s2cid = 203897553 }}</ref>\n\nIn 2013, a group of scientists led by [[Shoukhrat Mitalipov]] published the first report of embryonic stem cells created using SCNT. In this experiment, the researchers developed a protocol for using SCNT in human cells, which differs slightly from the one used in other organisms.  Four embryonic stem cell lines from human fetal somatic cells were derived from those blastocysts. All four lines were derived using oocytes from the same donor, ensuring that all [[mitochondrial DNA]] inherited was identical.<ref name=TrounsonComment>{{cite journal |vauthors=Trounson A, DeWitt ND | title = Pluripotent stem cells from cloned human embryos: success at long last | journal = Cell Stem Cell | volume = 12 | issue = 6 | pages = 636\u20138 | year = 2013 | pmid = 23746970 | doi = 10.1016/j.stem.2013.05.022 | doi-access = free }}</ref> A year later, a team led by [[Robert Lanza]] at Advanced Cell Technology reported that they had replicated Mitalipov's results and further demonstrated the effectiveness by cloning adult cells using SCNT.<ref name=TIME /><ref name="pmid24746675">{{cite journal |vauthors=Chung YG, Eum JH, Lee JE, Shim SH, Sepilian V, Hong SW, Lee Y, Treff NR, Choi YH, Kimbrel EA, Dittman RE, Lanza R, Lee DR | title = Human somatic cell nuclear transfer using adult cells | journal = Cell Stem Cell | volume = 14 | issue = 6 | pages = 777\u201380 | year = 2014 | pmid = 24746675 | doi = 10.1016/j.stem.2014.03.015 | doi-access = free }}</ref>\n\nIn 2018, the first successful [[clone (cell biology)|cloning]] of [[primates]] using SCNT was reported with the birth of two live female clones, [[crab-eating macaques]] named [[Zhong Zhong and Hua Hua]].<ref name="CELL-20180124">{{cite journal |author=Liu, Zhen|display-authors=etal |title=Cloning of Macaque Monkeys by Somatic Cell Nuclear Transfer |date=24 January 2018 |journal=[[Cell (journal)|Cell]] |volume=172 |issue=4 |pages=881\u2013887.e7 |doi=10.1016/j.cell.2018.01.020 |pmid=29395327 |s2cid=206567964 |doi-access=free }}</ref><ref name="SCINAT-20180124">*{{cite journal |last=Normile |first=Dennis |title=These monkey twins are the first primate clones made by the method that developed Dolly |url=http://www.sciencemag.org/news/2018/01/these-monkey-twins-are-first-primate-clones-made-method-developed-dolly |date=24 January 2018 |journal=[[Science (journal)|Science]] |doi=10.1126/science.aat1066 |access-date=24 January 2018 }}\n*{{cite journal |last=Cyranoski |first=David |title=First monkeys cloned with technique that made Dolly the sheep \u2013 Chinese scientists create cloned primates that could revolutionize studies of human disease. |date=24 January 2018 |journal=[[Nature (journal)|Nature]] |volume=553 |issue=7689 |pages=387\u2013388 |doi=10.1038/d41586-018-01027-z |pmid=29368720 |bibcode=2018Natur.553..387C |s2cid=4391482 |doi-access=free }}</ref><ref name="SA-20180124">{{cite web |last=Maron |first=Dina Fine |title=First Primate Clones Produced Using the "Dolly" Method \u2013 The success with monkeys could ignite new ethical debates and medical research |url=https://www.scientificamerican.com/article/first-primate-clones-produced-using-the-ldquo-dolly-rdquo-method/ |date=24 January 2018 |work=[[Scientific American]] |access-date=24 January 2018 }}</ref><ref name="BBC-20180124">{{cite news |last=Briggs |first=Helen |title=First monkey clones created in Chinese laboratory |url=https://www.bbc.com/news/health-42809445 |date=24 January 2018 |work=[[BBC News]] |access-date=24 January 2018 }}</ref><ref name="NYT-20180124gk">{{cite news |last=Kolata |first=Gina |title=Yes, They've Cloned Monkeys in China. That Doesn't Mean You're Next. |url=https://www.nytimes.com/2018/01/24/science/cloned-monkeys-china.html |date=24 January 2018 |work=[[The New York Times]] |access-date=25 January 2018 }}</ref>"}},
{"article_title": "Lighthouse", "pageid": "17725", "revid": "1060924885", "timestamp": "2021-12-18T15:02:59Z", "history_paths": [["Lighthouse --- Introduction ---", "History"]], "categories": ["lighthouses", "heraldic charges", "articles containing video clips", "ancient greek technology", "egyptian inventions", "greek inventions"], "heading_tree": {"Lighthouse --- Introduction ---": {"History": {"Ancient lighthouses": {}, "Modern construction": {}, "Lighting improvements": {}, "Optical systems": {}, "Modern lighthouses": {}, "Famous lighthouse builders": {}}, "Technology": {"Power": {}, "Light source": {"Laser light": {}, "Light characteristics": {}}, "Lens": {}}, "Building": {"Components": {}, "Design": {}, "Range lights": {}, "Location": {}}, "Maintenance": {"English-speaking countries": {}, "Soviet Union": {}, "India": {}, "Other countries": {}}, "Preservation": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Lighthouse --- Introduction ---|History": "{{Main|History of lighthouses}}\n\n [[File:A coruna torre de hercules sunset edit.jpg|thumb|upright=0.9|The [[Tower of Hercules]] lighthouse in northwest Spain]]\nBefore the development of clearly defined [[port]]s, mariners were guided by fires built on hilltops. Since elevating the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse.<ref>Trethewey, K. R.:Ancient Lighthouses, Jazz-Fusion Books (2018), 326pp. {{ISBN|978-0-99265-736-9}}</ref> In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for [[reef]]s and [[promontory|promontories]], unlike many modern lighthouses. The most famous lighthouse structure from antiquity was the [[Lighthouse of Alexandria|Pharos]] of [[Alexandria]], [[Egypt]], which collapsed following a series of earthquakes between 956 CE and 1323 CE.\n\nThe intact [[Tower of Hercules]] at [[A Coru\u00f1a]], Spain gives insight into ancient lighthouse construction; other evidence about lighthouses exists in depictions on coins and mosaics, of which many represent the lighthouse at [[Ostia Antica (archaeological site)|Ostia]]. Coins from Alexandria, Ostia, and [[Latakia|Laodicea in Syria]] also exist.\n\n The modern era of lighthouses began at the turn of the 18th century, as the number of lighthouses being constructed increased significantly due to much higher levels of [[Atlantic Ocean|transatlantic]] commerce. Advances in structural engineering and new and efficient lighting equipment allowed for the creation of larger and more powerful lighthouses, including ones exposed to the sea. The function of lighthouses was gradually changed from indicating ports to the providing of a visible warning against shipping hazards, such as rocks or reefs.\n\n[[File:Edystone Winstanley lighthouse Smeaton 1813.jpg|thumb|Original [[Eddystone Lighthouse#Winstanley's Lighthouse|Winstanley lighthouse]], Eddystone Rock, by Jaaziell Johnston, 1813.]]\nThe [[Eddystone Rocks]] were a major shipwreck hazard for mariners sailing through the [[English Channel]].<ref>{{citation|first=Samuel|last=Smiles|title=The Lives of the Engineers|year=1861|volume=Vol 2|page=16|url=https://archive.org/stream/livesofengineers02smil#page/16/mode/2up}}</ref> The [[Eddystone Lighthouse#Winstanley's lighthouse|first lighthouse built there]] was an octagonal wooden structure, anchored by 12 iron stanchions secured in the rock, and was built by [[Henry Winstanley]] from 1696 to 1698. His lighthouse was the first tower in the world to have been fully exposed to the open sea.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/340721/lighthouse/72148/The-beginning-of-the-modern-era|title=lighthouse|access-date=17 December 2012}}</ref>\n\nThe [[civil engineer]], [[John Smeaton]], rebuilt the [[Smeaton's Tower|lighthouse]] from 1756 to 1759;<ref name="MAJ">Majdalany, Fred: ''The Eddystone Light''. 1960</ref> his tower marked a major step forward in the design of lighthouses and remained in use until 1877. He modeled the shape of his lighthouse on that of an oak tree, using granite blocks. He rediscovered and used "[[hydraulic lime]]", a form of concrete that will set under water used by the Romans, and developed a technique of securing the granite blocks together using [[dovetail joint]]s and marble [[dowels]].<ref name="TRI">{{cite web|url=http://www.trinityhouse.co.uk/interactive/gallery/eddystone.html |title=Eddystone \u2013 Gallery |publisher=Trinity House |access-date=3 May 2010 |url-status=dead |archive-url=https://web.archive.org/web/20060909043743/http://www.trinityhouse.co.uk/interactive/gallery/eddystone.html |archive-date=9 September 2006 }}</ref> The dovetailing feature served to improve the [[structural stability]], although Smeaton also had to taper the thickness of the tower towards the top, for which he curved the tower inwards on a gentle gradient. This profile had the added advantage of allowing some of the energy of the waves to dissipate on impact with the walls. His lighthouse was the prototype for the modern lighthouse and influenced all subsequent engineers.<ref>{{cite book|title=Minutes of proceedings of the Institution of Civil Engineers|chapter=Note on the Eddystone Lighthouse|author=Douglass, James Nicholas|location=London|publisher=Institution of Civil Engineers|year=1878|volume=vol. 53, part 3|pages=247\u2013248|chapter-url=https://books.google.com/books?id=cx4AAAAAMAAJ&pg=PA247}}</ref>\n\n[[File:Smeaton's Lighthouse00.jpg|thumb|right|upright=1.1|[[John Smeaton]]'s rebuilt version of the [[Eddystone Lighthouse]], 1759. This represented a great step forward in lighthouse design.]]\nOne such influence was [[Robert Stevenson (civil engineer)|Robert Stevenson]], himself a seminal figure in the development of lighthouse design and construction.<ref name="NLB">{{cite web|url=http://www.nlb.org.uk/HistoricalInformation/StevensonEngineers/Robert-Stevenson/|title=NLB \u2013 Robert Stevenson|access-date=28 January 2013}}</ref> His greatest achievement was the construction of the [[Bell Rock Lighthouse]] in 1810, one of the most impressive feats of engineering of the age.{{Citation needed|date=May 2021}} This structure was based upon Smeaton's design, but with several improved features, such as the incorporation of rotating lights, alternating between red and white.<ref>{{citation|title=John Rennie, 1761\u20131821: The Life and Work of a Great Engineer|first=Cyril Thomas Goodman|last=Boucher|page=61|year=1963|url=https://books.google.com/books?id=1wu8AAAAIAAJ&pg=PA59}}</ref> Stevenson worked for the [[Northern Lighthouse Board]] for nearly fifty years<ref name="NLB" /> during which time he designed and oversaw the construction and later improvement of numerous lighthouses. He innovated in the choice of light sources, mountings, reflector design, the use of [[Fresnel lens]]es, and in rotation and shuttering systems providing lighthouses with individual signatures allowing them to be identified by seafarers. He also invented the movable jib and the balance-crane as a necessary part for lighthouse construction.\n[[File:Marjaniemen majakka.jpg|thumb|upright=1.1|[[Marjaniemi Lighthouse]], the 19th-century lighthouse in the [[Hailuoto]] island, neighbouring municipality of [[Oulu]], [[Finland]]]]\n[[Alexander Mitchell (engineer)|Alexander Mitchell]] designed the first [[screw-pile lighthouse]] \u2013 his lighthouse was built on piles that were [[screw]]ed into the sandy or muddy seabed. Construction of his design began in 1838 at the mouth of the [[Thames]] and was known as the [[Maplin Sands]] lighthouse, and first lit in 1841.<ref name=Tomlinson>{{cite book|title=Tomlinson's Cyclopaedia of Useful Arts|year=1852\u20131854|publisher=Virtue & Co.|location=London|page=[https://archive.org/details/cyclopdiaofuse02tomlrich/page/177 177]|editor=Tomlinson|url=https://archive.org/details/cyclopdiaofuse02tomlrich|quote=[Maplin Sands] was not, however, the first screw-pile lighthouse actually erected, for during the long preparation process which was carried on at Maplin Sands, a structure of the same principle had been begun and completed at Port Fleetwood...}}</ref> Although its construction began later, the [[Wyre Light (Fleetwood)|Wyre Light]] in Fleetwood, Lancashire, was the first to be lit (in 1840).<ref name=Tomlinson />\n\n Until 1782 the source of illumination had generally been wood pyres or burning coal. The [[Argand lamp]], invented in 1782 by the Swiss scientist [[Aim\u00e9 Argand]] revolutionized lighthouse illumination with its steady smokeless flame. Early models used ground glass which was sometimes tinted around the wick. Later models used a [[Gas mantle|mantle]] of [[thorium dioxide]] suspended over the flame, creating a bright, steady light.<ref>{{cite web|url=http://www.johnmoncrieff.co.uk/shop-2/products.php?cat=32|title=Lamp Glass Replacement Glass Lamp Shades, Oil Lamp Shades, Oil Lamp Chimneys, Oil Lamp Spares|url-status=dead|archive-url=https://web.archive.org/web/20140106160403/http://www.johnmoncrieff.co.uk/shop-2/products.php?cat=32|archive-date=6 January 2014}}</ref> The Argand lamp used [[whale oil]], [[colza]], [[olive oil]]<ref>"Lamp." ''Encyclop\u00e6dia Britannica: or, a dictionary of Arts, Science, and Miscellaneous Literature.''  6th ed. 1823 [https://books.google.com/books?id=T8wnAAAAMAAJ&pg=PA505&lpg=PA505&dq=%22argand+lamp%22+%22olive+oil%22&source=bl&ots=K9CxKs3AJG&sig=9wwDAF6jlwx9zV-xjvALVg_EKEs&hl=en&ei=rxPdTuOVLMLX0QHpqvXWCg&sa=X&oi=book_result&ct=result&resnum=6&ved=0CFkQ6AEwBQ#v=onepage&q=%22argand%20lamp%22%20%22olive%20oil%22&f=false Web.] 5 December 2011</ref> or other [[vegetable oil]] as fuel, supplied by a [[gravity feed]] from a reservoir mounted above the burner. The lamp was first produced by [[Matthew Boulton]], in partnership with Argand, in 1784, and became the standard for lighthouses for over a century.<ref>{{cite web|url=https://www.britannica.com/technology/lighthouse/Modern-lighthouses#ref668277|title=Modern Lighthouses|website=Encyclopaedia Brittanica|access-date=4 August 2021}}</ref>\n\n[[South Foreland Lighthouse]] was the first tower to successfully use an electric light in 1875. The lighthouse's carbon [[arc lamp]]s were powered by a steam-driven [[magneto (generator)|magneto]].<ref>{{cite book |last=Baird |first=Spencer Fullerton|title=Annual record of science and industry |publisher=Harper & Brothers|location=New York|year=1876|pages=460}}</ref> [[John Richardson Wigham]] was the first to develop a system for [[coal gas|gas]] illumination of lighthouses. His improved gas 'crocus' burner at the [[Baily Lighthouse]] near Dublin was 13 times more powerful than the most brilliant light then known.<ref name=cil>{{cite journal| title=John Richardson Wigham 1829\u20131906 | url=http://www.commissionersofirishlights.com/media/35546/Beam_2006.PDF#page=23 | publisher=Commissioners of Irish Lights | journal=BEAM | volume=35 | date=2006\u20132007 | pages=21\u201322|archive-url=https://web.archive.org/web/20120312014229/http://www.commissionersofirishlights.com/media/35546/Beam_2006.PDF|archive-date=12 March 2012}}</ref>\n[[File:Sumburgh Lighthouse Lamp.jpg|thumb|An {{convert|85|mm|in}} Chance Brothers ''Incandescent Petroleum Vapour Installation'' which produced the light for the [[Sumburgh Head]] lighthouse until 1976. <!-- All text in this caption after this comment should be put somewhere in the article body instead. -->The lamp (made in approx. 1914) burned vaporized [[kerosene]] (paraffin); the vaporizer was heated by a [[denatured alcohol]] (methylated spirit) burner to light. When lit, some of the vaporised fuel was diverted to a [[Bunsen burner]] to keep the vaporizer warm and the fuel in vapor form. The fuel was forced up to the lamp by air; the keepers had to pump the air container up every hour or so, pressurizing the paraffin container to force the fuel to the lamp. The "white sock" pictured is  an unburnt mantle on which the vapor burned.]]\nThe vaporized [[oil burner]] was invented in 1901 by [[Arthur Kitson]], and improved by David Hood at [[Trinity House]]. The fuel was vaporized at high pressure and burned to heat the mantle, giving an output of over six times the luminosity of traditional oil lights. The use of gas as illuminant became widely available with the invention of the [[Dal\u00e9n light]] by Swedish engineer [[Gustaf Dal\u00e9n]]. He used [[Agamassan]] (Aga), a [[Substrate (materials science)|substrate]], to absorb the gas, allowing the gas to be stored, and hence used, safely. Dal\u00e9n also invented the '[[sun valve]]', which automatically regulated the light and turned it off during the daytime.{{Citation needed paragraph|date=May 2021}} The technology was the predominant light source in lighthouses from the 1900s to the 1960s, when electric lighting had become dominant.<ref>{{cite web|url=http://www.aga.com/web/web2000/com/WPPcom.nsf/pages/History_SunValve|title=The Linde Group - Gases Engineering Healthcare -|access-date=6 April 2017|archive-url=https://web.archive.org/web/20151018000926/http://www.aga.com/web/web2000/com/WPPcom.nsf/pages/History_SunValve|archive-date=18 October 2015|url-status=dead}}</ref>\n\n [[File:Fresnel lighthouse lens diagram.png|thumb|right|Diagram depicting how a spherical [[Fresnel lens]] collimates light]]\nWith the development of the steady illumination of the Argand lamp, the application of optical lenses to increase and focus the light intensity became a practical possibility. [[William Hutchinson (privateer)|William Hutchinson]] developed the first practical optical system in 1763, known as a [[catoptrics|catoptric]] system.{{Citation needed|date=May 2021}} This rudimentary system effectively collimated the emitted light into a concentrated beam, thereby greatly increasing the light's visibility.<ref>{{cite encyclopedia|url=http://www.britannica.com/EBchecked/topic/340721/lighthouse/72152/Oil-lamps|title=Lighthouse|encyclopedia=Encyclop\u00e6dia Britannica|access-date=6 January 2014}}</ref> The ability to focus the light led to the first revolving lighthouse beams, where the light would appear to the mariners as a series of intermittent flashes. It also became possible to transmit complex signals using the light flashes.\n\nFrench physicist and engineer [[Augustin-Jean Fresnel]] developed the multi-part [[Fresnel lens]] for use in lighthouses. His design allowed for the construction of lenses of large [[aperture]] and short [[focal length]], without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. A Fresnel lens can also capture more oblique light from a light source, thus allowing the light from a lighthouse equipped with one to be visible over greater distances.\n\nThe first Fresnel lens was used in 1823 in the [[Cordouan lighthouse]] at the mouth of the [[Gironde estuary]]; its light could be seen from more than {{convert|20|mi|km}} out.<ref>Watson, Bruce. "Science Makes a Better Lighthouse Lens." ''Smithsonian''. August 1999 v30 i5 p30.\nproduced in ''Biography Resource Center''. Farmington Hills, Mich.: Thomson Gale. 2005.</ref> Fresnel's invention increased the [[luminosity]] of the lighthouse lamp by a factor of four and his system is still in common use.\n\n The introduction of electrification and [[automatic lamp changer]]s began to make [[lighthouse keeper]]s obsolete. For many years, lighthouses still had keepers, partly because lighthouse keepers could serve as a [[emergency service|rescue service]] if necessary. Improvements in maritime navigation and safety such as [[satellite navigation]] systems such as [[GPS]] led to the phasing out of non-automated lighthouses across the world.<ref>{{cite web|url=http://www.nps.gov/history/maritime/keep/keep19th.htm|title=Maritime Heritage Program - National Park Service|access-date=6 April 2017}}</ref> In Canada, this trend has been stopped and there are still 50 staffed light stations, with 27 on the west coast alone.<ref>{{cite web|url=http://www.fogwhistle.ca/bclights|title=Lighthouses of British Columbia|access-date=3 November 2011|archive-url=https://web.archive.org/web/20111103070010/http://www.fogwhistle.ca/bclights/|archive-date=3 November 2011|url-status=dead}}</ref>\n\nRemaining modern lighthouses are usually illuminated by a single stationary flashing light powered by solar-charged batteries mounted on a steel skeleton tower.<ref name="Crompton"/> Where the power requirement is too great for solar power, ''cycle charging'' by diesel generator is used: to save fuel and to increase periods between maintenance the light is battery powered, with the generator only coming into use when the battery has to be charged.<ref>{{cite book |last1=Nicholson |first1=Christopher |title=Rock lighthouses of Britain : the end of an era? |date=2000 |publisher=Whittles |location=Caithness, Scotland |isbn=978-1870325417 |page=126}}</ref>\n\n [[John Smeaton]] is noteworthy for having designed the third and most famous [[Eddystone Lighthouse]], but some builders are well known for their work in building multiple lighthouses. The Stevenson family ([[Robert Stevenson (civil engineer)|Robert]], [[Alan Stevenson|Alan]], [[David Stevenson (engineer)|David]], [[Thomas Stevenson|Thomas]], [[David Alan Stevenson|David Alan]], and [[Charles Alexander Stevenson|Charles]]) made lighthouse building a three-generation profession in Scotland. \n[[Richard Henry Brunton]] designed and built 26 [[Template:Lighthouses of Japan|Japanese lighthouses]] in [[Meiji (era)|Meiji Era]] Japan, which became known as Brunton's "children".<ref>{{cite news | url=https://www.icevirtuallibrary.com/doi/abs/10.1680/imotp.1901.18577 |title=Obituary - Richard Henry Brunton | work=Minutes of the Proceedings of the Institution of Civil Engineers |volume=145 |issue=1901 |year=1901 |pages=340\u2013341 |doi=10.1680/imotp.1901.18577 |access-date=20 April 2018}}</ref> Blind Irishman [[Alexander Mitchell (engineer)|Alexander Mitchell]] invented and built a number of screw-pile lighthouses. Englishman [[James Nicholas Douglass|James Douglass]] was knighted for his work on the fourth Eddystone Lighthouse.<ref>{{cite DNBSupp|title=Douglass, James Nicholas |first=Thomas Hudson|last=Beare}}</ref>\n\n[[United States Army Corps of Engineers]] Lieutenant [[George Meade]] built numerous lighthouses along the Atlantic and Gulf coasts before gaining wider fame as the winning general at the [[Battle of Gettysburg]].  Colonel [[Orlando M. Poe]], engineer to [[General William Tecumseh Sherman]] in the Siege of Atlanta, designed and built some of the most exotic lighthouses in the most difficult locations on the U.S. [[Great Lakes]].<ref>{{cite web|url=http://www.nps.gov/history/maritime/keep/architect.htm|title=Maritime Heritage Program - National Park Service|access-date=6 April 2017}}</ref>\n\nFrench merchant navy officer [[Marius Michel Pasha]] built almost a hundred lighthouses along the coasts of the [[Ottoman Empire]] in a period of twenty years after the [[Crimean War]] (1853\u20131856).<ref name="hnet">{{cite web |url=http://www.h-net.org/reviews/showrev.php?id=11049 |publisher=Humanities and Social Sciences Net Online |title=Review of Thobie, Jacques, L'administration generale des phares de l'Empire ottoman et la societe Collas et Michel, 1860\u20131960. H-Mediterranean, H-Net Reviews. January, 2006 | author=Guigueno, Vincent |date=January 2006 |access-date=20 September 2010}}</ref>"}},
{"article_title": "Liquid-crystal display", "pageid": "17932", "revid": "1062807680", "timestamp": "2021-12-30T17:20:53Z", "history_paths": [["Liquid-crystal display --- Introduction ---", "History"]], "categories": ["liquid crystal displays", "american inventions", "display technology", "articles containing video clips"], "heading_tree": {"Liquid-crystal display --- Introduction ---": {"General characteristics": {}, "History": {"Background": {}, "1960s": {}, "1970s": {}, "1980s": {}, "1990s": {}, "2000s\u20132010s": {}}, "Illumination": {}, "Connection to other circuits": {}, "Passive-matrix": {}, "Active-matrix technologies": {"Twisted nematic (TN)": {}, "In-plane switching (IPS)": {"Super In-plane switching (S-IPS)": {}}, "M+ or RGBW controversy": {}, "IPS in comparison to AMOLED": {}, "Advanced fringe field switching (AFFS)": {}, "Vertical alignment (VA)": {}, "Blue phase mode": {}}, "Quality control": {}, "\"Zero-power\" (bistable) displays": {}, "Specifications": {}, "Advantages and disadvantages": {"Advantages": {}, "Disadvantages": {}}, "Chemicals used": {"Environmental impact": {}}, "See also": {}, "References": {}, "External links": {"General information": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Liquid-crystal display --- Introduction ---|History": "The origins and the complex history of liquid-crystal displays from the perspective of an insider during the early days were described by Joseph A. Castellano in ''Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry''.<ref>''Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry'', Joseph A. Castellano, 2005 World Scientific Publishing Co. Pte. Ltd., {{ISBN|981-238-956-3}}.</ref>\nAnother report on the origins and history of LCD from a different perspective until 1991 has been published by Hiroshi Kawamoto, available at the [[IEEE]] History Center.<ref>{{cite journal | last1=Kawamoto | first1=Hiroshi | year=2002 | title=The History of Liquid-Crystal Displays | url=http://ieee.org/portal/cms_docs_iportals/iportals/aboutus/history_center/LCD-History.pdf | journal=Proceedings of the IEEE | volume=90 | issue=4| pages=460\u2013500 | doi=10.1109/JPROC.2002.1002521}}</ref>\nA description of Swiss contributions to LCD developments, written by Peter J. Wild, can be found at the ''Engineering and Technology History Wiki''.<ref>{{cite web |url=http://ethw.org/First-Hand:Liquid_Crystal_Display_Evolution_-_Swiss_Contributions|title=First-Hand Histories: Liquid Crystal Display Evolution \u2014 Swiss Contributions |work=Engineering and Technology History Wiki |publisher=ETHW |access-date=June 30, 2017}}</ref>\n\n {{Main|Liquid crystal|Thin-film transistor}}\n\nIn 1888,<ref>\n{{Cite book\n | title = Supramolecular Chemistry\n | edition = 2nd\n | author1=Jonathan W. Steed |author2=Jerry L. Atwood\n | name-list-style=amp| publisher = John Wiley and Sons\n | year = 2009\n | isbn = 978-0-470-51234-0\n | page = 844\n | url = https://books.google.com/books?id=Jt1I74g6_28C&q=liquid-crystal%201888&pg=PA844\n}}</ref> [[Friedrich Reinitzer]] (1858\u20131927) discovered the liquid crystalline nature of cholesterol extracted from carrots (that is, two melting points and generation of colors) and published his findings at a meeting of the Vienna Chemical Society on May 3, 1888 (F. Reinitzer: ''Beitr\u00e4ge zur Kenntniss des Cholesterins, Monatshefte f\u00fcr Chemie (Wien) 9, 421\u2013441 (1888)'').<ref>Tim Sluckin: ''Ueber die Natur der kristallinischen Fl\u00fcssigkeiten und fl\u00fcssigen Kristalle'' (''About the Nature of Crystallised Liquids and Liquid Crystals''), Bunsen-Magazin, 7.Jahrgang, 5/2005</ref> In 1904, [[Otto Lehmann (physicist)|Otto Lehmann]] published his work ''"Fl\u00fcssige Kristalle"'' (Liquid Crystals). In 1911, [[Charles Mauguin]] first experimented with liquid crystals confined between plates in thin layers.\n\nIn 1922, [[Georges Friedel]] described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, [[Vsevolod Frederiks]] devised the electrically switched light valve, called the [[Fr\u00e9edericksz transition]], the essential effect of all LCD technology. In 1936, the [[Marconi Company|Marconi Wireless Telegraph company]] patented the first practical application of the technology, ''"The Liquid Crystal Light Valve"''. In 1962, the first major English language publication ''Molecular Structure and Properties of Liquid Crystals'' was published by Dr. [[George W. Gray]].<ref>{{Cite journal|doi=10.1039/a902682g |title=Liquid crystals for twisted nematic display devices |year=1999 |last1=Gray |first1=George W. |last2=Kelly |first2=Stephen M. |journal=Journal of Materials Chemistry |volume=9 |pages=2037\u20132050|issue=9}}</ref> In 1962, Richard Williams of [[RCA]] found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.<ref>{{cite journal | last1=Williams | first1=R. | year=1963 | title=Domains in liquid crystals | journal=J. Phys. Chem. | volume=39 | issue=2| pages=382\u2013388 | doi=10.1063/1.1734257| bibcode=1963JChPh..39..384W }}</ref>\n\nThe [[MOSFET]] (metal-oxide-semiconductor field-effect transistor) was invented by [[Mohamed M. Atalla]] and [[Dawon Kahng]] at [[Bell Labs]] in 1959, and presented in 1960.<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960 - Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]]|access-date=29 July 2019}}</ref><ref>{{cite journal |last1=Atalla |first1=M. |author1-link=Mohamed Atalla |last2=Kahng |first2=D. |author2-link=Dawon Kahng |title=Silicon-silicon dioxide field induced surface devices |journal=IRE-AIEE Solid State Device Research Conference |date=1960}}</ref> Building on their work with MOSFETs, [[Paul K. Weimer]] at [[RCA]] developed the [[thin-film transistor]] (TFT) in 1962.<ref>{{cite journal |last1=Weimer |first1=Paul K. |author1-link=Paul K. Weimer |title=The TFT A New Thin-Film Transistor |journal=[[Proceedings of the IRE]] |date=1962 |volume=50 |issue=6 |pages=1462\u20131469 |doi=10.1109/JRPROC.1962.288190 |s2cid=51650159 |issn=0096-8390}}</ref> It was a type of MOSFET distinct from the standard bulk MOSFET.<ref name="Kimizuka">{{cite book |last1=Kimizuka |first1=Noboru |last2=Yamazaki |first2=Shunpei |title=Physics and Technology of Crystalline Oxide Semiconductor CAAC-IGZO: Fundamentals |date=2016 |publisher=John Wiley & Sons |isbn=9781119247401 |page=217 |url=https://books.google.com/books?id=_iTRDAAAQBAJ&pg=PA217}}</ref>\n\n In 1964, [[George H. Heilmeier]], then working at the RCA laboratories on the effect discovered by Williams achieved the switching of colors by field-induced realignment of dichroic dyes in a homeotropically oriented liquid crystal. Practical problems with this new electro-optical effect made Heilmeier continue to work on scattering effects in liquid crystals and finally the achievement of the first operational liquid-crystal display based on what he called the ''[[Dynamic Scattering Mode|dynamic scattering mode]]'' (DSM). Application of a voltage to a DSM display switches the initially clear transparent liquid crystal layer into a milky turbid state. DSM displays could be operated in transmissive and in reflective mode but they required a considerable current to flow for their operation.<ref name="cast06">{{Cite journal| title=Modifying Light | first1=Joseph A. | last1=Castellano | journal=American Scientist | volume=94 | issue=5 | year=2006 | pages=438\u2013445 | doi=10.1511/2006.61.438}}</ref><ref>{{Cite journal|doi=10.1080/15421406908084910 |title=Guest-Host Interactions in Nematic Liquid Crystals |year=1969 |last1=Heilmeier |first1=George |last2=Castellano |first2=Joseph |last3=Zanoni |first3=Louis |journal=Molecular Crystals and Liquid Crystals |volume=8 |pages=293\u2013304}}</ref><ref>{{cite journal | last1=Heilmeier | first1=G. H. | last2=Zanoni | first2=L. A. | last3=Barton | first3=L. A. | year=1968 | title=Dynamic scattering: A new electrooptic effect in certain classes of nematic liquid crystals | journal=Proc. IEEE | volume=56 | issue=7| pages=1162\u20131171 | doi=10.1109/proc.1968.6513}}</ref><ref>{{cite journal|last=Gross|first=Benjamin|title=How RCA lost the LCD|journal=IEEE Spectrum|volume=49|issue=11|pages=38\u201344|date=November 2012|doi=10.1109/mspec.2012.6341205|s2cid=7947164}}</ref> [[George H. Heilmeier]] was inducted in the National Inventors Hall of Fame<ref>[http://seura.com/1_3_09_induction_heilmeier.html National Inventors Hall of Fame] {{Webarchive|url=https://web.archive.org/web/20140426233228/http://seura.com/1_3_09_induction_heilmeier.html |date=April 26, 2014 }} (Retrieved 2014-04-25)</ref> and credited with the invention of LCDs. Heilmeier's work is an [[List of IEEE milestones|IEEE Milestone]].<ref>{{cite web |url=http://www.ieeeghn.org/wiki/index.php/Milestones:Liquid_Crystal_Display,_1968 |title=Milestones: Liquid Crystal Display, 1968 |work=IEEE Global History Network |publisher=IEEE |access-date=August 4, 2011}}</ref>\n\nIn the late 1960s, pioneering work on liquid crystals was undertaken by the UK's [[Royal Radar Establishment]] at [[Malvern, Worcestershire|Malvern]], England. The team at RRE supported ongoing work by George William Gray and his team at the [[University of Hull]] who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.\n\nThe idea of a [[Thin-film transistor|TFT]]-based liquid-crystal display (LCD) was conceived by [[Bernard J. Lechner|Bernard Lechner]] of [[RCA Laboratories]] in 1968.<ref name="Kawamoto">{{cite journal |last1=Kawamoto |first1=H. |title=The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal |journal=Journal of Display Technology |date=2012 |volume=8 |issue=1 |pages=3\u20134 |doi=10.1109/JDT.2011.2177740 |bibcode=2012JDisT...8....3K |issn=1551-319X}}</ref> Lechner, F.J. Marlowe, E.O. Nester and J. Tults demonstrated the concept in 1968 with an 18x2 matrix [[dynamic scattering mode]] (DSM) LCD that used standard discrete [[MOSFET]]s.<ref>{{cite book |last1=Castellano |first1=Joseph A. |title=Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry |date=2005 |publisher=[[World Scientific]] |isbn=9789812389565 |pages=41\u20132 |url=https://books.google.com/books?id=vrtpDQAAQBAJ&pg=PA41}}</ref>\n\n On December 4, 1970, the [[twisted nematic field effect]] (TN) in liquid crystals was filed for patent by [[Hoffmann-LaRoche]] in Switzerland, ([http://www.lcd-experts.net/ Swiss patent No. 532 261]) with [[Wolfgang Helfrich]] and [[Martin Schadt]] (then working for the Central Research Laboratories) listed as inventors.<ref name="cast06" /> Hoffmann-La Roche licensed the invention to Swiss manufacturer [[Brown, Boveri & Cie]], its [[joint venture]] partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which soon produced the first digital [[Quartz watch|quartz wristwatches]] with TN-LCDs and numerous other products. [[James Fergason]], while working with Sardari Arora and [[Alfred Saupe]] at [[Kent State University]] [[Liquid Crystal Institute]], filed an identical patent in the United States on April 22, 1971.<ref>{{cite web | title=Modifying Light | work=American Scientist Online | url=http://www.americanscientist.org/template/AssetDetail/assetid/53321/page/4;jsessionid=aaa6J-GFIciRx2%3Ci%3ELive | access-date=December 28, 2007 | archive-url=https://web.archive.org/web/20081220055207/http://www.americanscientist.org/template/AssetDetail/assetid/53321/page/4;jsessionid=aaa6J-GFIciRx2%3Ci%3ELive | archive-date=December 20, 2008 | url-status=dead | df=mdy-all }}</ref> In 1971, the company of Fergason, [[ILIXCO]] (now [[LXD Incorporated]]), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of [[Seiko]] received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.<ref>{{cite web|url=https://patents.google.com/patent/US3881311A/en|title=Driving arrangement for passive time indicating devices|access-date=April 10, 2019}}</ref> In 1972, the first wristwatch with TN-LCD was launched on the market: The Gruen Teletime which was a four digit display watch.\n\nIn 1972, the concept of the [[Active matrix|active-matrix]] [[Thin-film transistor|thin-film transistor (TFT)]] liquid-crystal display panel was prototyped in the United States by [[T. Peter Brody]]'s team at [[Westinghouse Electric (1886)|Westinghouse]], in [[Pittsburgh, Pennsylvania]].<ref>Brody, T.P., ''"Birth of the Active Matrix"'', Information Display, Vol. 13, No. 10, 1997, pp. 28\u201332.</ref> In 1973, Brody, J. A. Asars and G. D. Dixon at [[Westinghouse Electric Corporation|Westinghouse Research Laboratories]] demonstrated the first [[thin-film-transistor liquid-crystal display]] (TFT LCD).<ref name="Kuo">{{cite journal |last1=Kuo |first1=Yue |title=Thin Film Transistor Technology\u2014Past, Present, and Future |journal=The Electrochemical Society Interface |date=1 January 2013 |volume=22 |issue=1 |pages=55\u201361 |doi=10.1149/2.F06131if |bibcode=2013ECSIn..22a..55K |url=https://www.electrochem.org/dl/interface/spr/spr13/spr13_p055_061.pdf |issn=1064-8208|doi-access=free }}</ref><ref>{{cite journal |last1=Brody |first1=T. Peter |author1-link=T. Peter Brody |last2=Asars |first2=J. A. |last3=Dixon |first3=G. D. |title=A 6 \u00d7 6 inch 20 lines-per-inch liquid-crystal display panel |journal=[[IEEE Transactions on Electron Devices]] |date=November 1973 |volume=20 |issue=11 |pages=995\u20131001 |doi=10.1109/T-ED.1973.17780 |bibcode=1973ITED...20..995B |issn=0018-9383}}</ref> {{As of|2013}}, all modern [[high-resolution]] and high-quality [[electronic visual display]] devices use TFT-based [[active matrix]] displays.<ref>{{cite book |last1=Brotherton |first1=S. D. |title=Introduction to Thin Film Transistors: Physics and Technology of TFTs |date=2013 |publisher=[[Springer Science & Business Media]] |isbn=9783319000022 |page=74 |url=https://books.google.com/books?id=E0x0Zghk7okC&pg=PT74}}</ref> Brody and Fang-Chen Luo demonstrated the first flat [[active-matrix liquid-crystal display]] (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.<ref name="Kawamoto"/>\n\nIn 1972 [[Rockwell International|North American Rockwell Microelectronics Corp]] introduced the use of DSM LCD displays for [[calculator]]s for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.<ref>{{cite journal |last1=Dale |first1=Rodney |last2=Millichamp |first2=David |date=28 September 1972 |title=Liquid Crystals Get Their Sparkle From Mass Market |journal=The Engineer |pages=34\u201336}}</ref> [[Sharp Corporation]] followed with DSM LCD displays for pocket-sized calculators in 1973<ref>{{cite journal |date=December 1973 |title=What's New In Electronics: 100-hour calculator |journal=Popular Science |pages=87}}</ref> and then mass-produced TN LCD displays for watches in 1975.<ref name="auburn">[https://web.archive.org/web/20051031052032/http://web6.duc.auburn.edu/~boultwr/lcdnote.pdf Note on the Liquid Crystal Display Industry], [[Auburn University]], 1995</ref> Other Japanese companies soon took a leading position in the wristwatch market, like [[Seiko]] and its first 6-digit TN-LCD quartz wristwatch. Color LCDs based on ''Guest-Host'' interaction were invented by a team at RCA in 1968.<ref>Heilmeier, G. H., Castellano, J. A. and Zanoni, L. A.: ''Guest-host interaction in nematic liquid crystals.'' Mol. Cryst. Liquid Cryst. vol. 8, p. 295, 1969</ref> A particular type of such a color LCD was developed by Japan's Sharp Corporation in the 1970s, receiving patents for their inventions, such as a patent by Shinji Kato and Takaaki Miyazaki in May 1975,<ref>{{cite web|url=https://patents.google.com/patent/JPS51139582A/en|title=Liquid crystal display units|access-date=April 10, 2019}}</ref> and then improved by Fumiaki Funada and Masataka Matsuura in December 1975.<ref>{{cite web|url=https://patents.google.com/patent/JPS5279948A/en|title=Liquid crystal color display device|access-date=April 10, 2019}}</ref> [[TFT LCD]]s similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,<ref>{{cite web|url=https://patents.google.com/patent/JPS5327390A/en|title=Liquid crystal display device|access-date=April 10, 2019}}</ref> then improved in 1977 by a Sharp team consisting of Kohei Kishi, Hirosaku Nonomura, Keiichiro Shimizu, and Tomio Wada.<ref>{{cite web|url=https://patents.google.com/patent/JPS5437697A/en|title=Liquid crystal display unit of matrix type|access-date=April 10, 2019}}</ref> However, these TFT-LCDs were not yet ready for use in products, as problems with the materials for the TFTs were not yet solved.\n\n In 1983, researchers at [[Brown, Boveri & Cie]] (BBC) Research Center, [[Switzerland]], invented the ''[[super-twisted nematic]] (STN) structure'' for [[passive matrix]]-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,<ref>European Patent No. EP 0131216: Amstutz H., Heimgartner D., Kaufmann M., Scheffer T.J., "Fl\u00fcssigkristallanzeige," Oct. 28, 1987.</ref> {{US patent|4634229}} and many more countries. In 1980, Brown Boveri started a 50/50 joint venture with the Dutch Philips company, called Videlec.<ref>G.H. Gessinger; Materials and Innovative Product development; Elsevier; 2009; page 204; https://books.google.com/books?id=-3Lu_bW2PZoC&pg=PA204&lpg=PA204&dq=videlec+Philips+Brown+Boveri&source=bl&ots=9M39YqQvpX&sig=xNwWmzGX0KK07VpzptMhdmtYGgA&hl=en&sa=X&ved=0ahUKEwiLhKeGk6jVAhXMblAKHWU2DAwQ6AEIJjAA#v=onepage&q=videlec%20Philips%20Brown%20Boveri&f=false</ref> Philips had the required know-how to design and build integrated circuits for the control of large LCD panels. In addition, Philips had better access to markets for electronic components and intended to use LCDs in new product generations of hi-fi, video equipment and telephones. In 1984, Philips researchers Theodorus Welzen and Adrianus de Vaan invented a video speed-drive scheme that solved the slow response time of STN-LCDs, enabling high-resolution, high-quality, and smooth-moving video images on STN-LCDs.<ref name="EP0175417B1">Liquid Crystal Display Device; T.L. Welzen; A.J.S.M. de Vaan; European patent EP0175417B1; 23 May 1990; filed 19 September 1984; https://worldwide.espacenet.com/publicationDetails/biblio?CC=EP&NR=0175417B1&KC=B1&FT=D&ND=4&date=19900523&DB=EPODOC&locale=en_EP#; US patent US4902105A; https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=US&NR=4902105A&KC=A&FT=D&ND=5&date=19900220&DB=EPODOC&locale=en_EP#</ref> In 1985, Philips inventors Theodorus Welzen and Adrianus de Vaan solved the problem of driving high-resolution STN-LCDs using low-voltage (CMOS-based) drive electronics, allowing the application of high-quality (high resolution and video speed) LCD panels in battery-operated portable products like notebook computers and mobile phones.<ref name="EP0221613B1">Low Drive Voltage Display Device; T.L. Welzen; A.J.S.M. de Vaan; European patent EP0221613B1; 10 July 1991, filed 4 November 1985; https://worldwide.espacenet.com/publicationDetails/biblio?CC=EP&NR=0221613B1&KC=B1&FT=D&ND=4&date=19910710&DB=EPODOC&locale=en_EP#; US patent US4783653A; https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=US&NR=4783653A&KC=A&FT=D&ND=5&date=19881108&DB=EPODOC&locale=en_EP#</ref> In 1985, Philips acquired 100% of the Videlec AG company based in Switzerland. Afterwards, Philips moved the Videlec production lines to the Netherlands. Years later, Philips successfully produced and marketed complete modules (consisting of the LCD screen, microphone, speakers etc.) in high-volume production for the booming mobile phone industry.\n\nThe first color [[LCD televisions]] were developed as [[handheld television]]s in Japan. In 1980, [[Hattori Seiko]]'s R&D group began development on color LCD pocket televisions.<ref name="spin">''[[Spin (magazine)|Spin]]'', [https://books.google.co.uk/books?id=ImJFcBcCvUoC&pg=PA55 Jul 1985, page 55]</ref> In 1982, [[Seiko Epson]] released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.<ref>{{cite web|url=http://global.epson.com/company/corporate_history/milestone_products/14_tv_watch.html|title=TV Watch - Epson|website=global.epson.com|access-date=April 10, 2019}}</ref><ref name="peres">Michael R. Peres, [https://books.google.co.uk/books?id=NMJxyAwGvKcC&pg=PA306 ''The Focal Encyclopedia of Photography'', page 306], [[Taylor & Francis]]</ref> Sharp Corporation introduced [[Dot matrix display|dot matrix]] TN-LCD in 1983.<ref name="auburn" /> In 1984, Epson released the ET-10, the first full-color, pocket LCD television.<ref>[https://www.epson.co.uk/viewcon/corporatesite/cms/index/28 A HISTORY OF CREATING INSPIRATIONAL TECHNOLOGY], [[Epson]]</ref> The same year, [[Citizen Watch]],<ref name="science">''[[Popular Science]]'', [https://books.google.co.uk/books?id=lgAAAAAAMBAJ&pg=PA150 May 1984, page 150]</ref> introduced the Citizen Pocket TV,<ref name="spin" /> a 2.7-inch color LCD TV,<ref name="science" /> with the first commercial [[TFT LCD]] display.<ref name="spin" /> In 1988, Sharp demonstrated a 14-inch, active-matrix, full-color, full-motion TFT-LCD. This led to Japan launching an LCD industry, which developed large-size LCDs, including TFT [[computer monitor]]s and LCD televisions.<ref name="kawamoto">Hirohisa Kawamoto (2013), [https://ieeexplore.ieee.org/document/6487587/ The history of liquid-crystal display and its industry], ''HISTory of ELectro-technology CONference (HISTELCON), 2012 Third IEEE'', [[Institute of Electrical and Electronics Engineers]], DOI 10.1109/HISTELCON.2012.6487587</ref> Epson developed the [[3LCD]] projection technology in the 1980s, and licensed it for use in projectors in 1988.<ref>[https://www.epson.co.uk/gb/en/viewcon/corporatesite/cms/index/11298 Find out what is an LCD Projector, how does it benefit you, and the difference between LCD and 3LCD here], Epson</ref> Epson's VPJ-700, released in January 1989, was the world's first [[Handheld projector|compact]], full-color [[LCD projector]].<ref name="peres" />\n\n In 1990, under different titles, inventors conceived electro optical effects as alternatives to ''twisted nematic field effect LCDs'' (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/biblio?locale=en_EP&CC=US&NR=3834794 |title=Espacenet \u2014 Bibliographic data |publisher=Worldwide.espacenet.com |date=1974-09-10 |access-date=August 15, 2014}}</ref><ref>{{US patent|3834794}}: R. Soref, ''Liquid crystal electric field sensing measurement and display device'', filed June 28, 1973.</ref> To take full advantage of the properties of this ''[[In Plane Switching]] (IPS) technology'' further work was needed. After thorough analysis, details of advantageous embodiments are filed in [[Germany]] by Guenter Baur ''et al.'' and patented in various countries.<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/biblio?locale=en_EP&CC=US&NR=5576867 |title=Espacenet \u2014 Bibliographic data |publisher=Worldwide.espacenet.com |date=1996-11-19 |access-date=August 15, 2014}}</ref><ref>{{US patent|5576867}}: G. Baur, W. Fehrenbach, B. Staudacher, F. Windscheid, R. Kiefer, ''Liquid crystal switching elements having a parallel electric field and beta<sub>o</sub> which is not 0 or 90 degrees'', filed Jan 9, 1990.</ref> The Fraunhofer Institute ISE in Freiburg, where the inventors worked, assigns these patents to Merck KGaA, Darmstadt, a supplier of LC substances. In 1992, shortly thereafter, engineers at [[Hitachi]] work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/biblio?locale=en_EP&CC=US&NR=5598285 |title=Espacenet \u2014 Bibliographic data |publisher=Worldwide.espacenet.com |date=1997-01-28 |access-date=August 15, 2014}}</ref><ref>{{US patent|5598285}}: K. Kondo, H. Terao, H. Abe, M. Ohta, K. Suzuki, T. Sasaki, G. Kawachi, J. Ohwada, ''Liquid crystal display device'', filed Sep 18, 1992 and Jan 20, 1993.</ref>\n\nHitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (''Super IPS''). [[NEC]] and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, [[Samsung]] developed the optical patterning technique that enables multi-domain LCD. Multi-domain and [[In Plane Switching]] subsequently remain the dominant LCD designs through 2006.<ref>{{cite journal|url=http://www.nature.com/nature/journal/v382/n6593/pdf/382666c0.pdf |title=Optical Patterning |journal=Nature |date=August 22, 1996 |access-date=June 13, 2008}}</ref> In the late 1990s, the LCD industry began shifting away from Japan, towards [[South Korea]] and [[Taiwan]],<ref name="kawamoto" /> which later shifted to China.\n\n In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.<ref>Competing display technologies for the best image performance; A.J.S.M. de Vaan; Journal of the society of information displays, Volume 15, Issue 9 September 2007 Pages 657\u2013666; http://onlinelibrary.wiley.com/doi/10.1889/1.2785199/abstract?</ref> In the fourth quarter of 2007, LCD televisions surpassed CRT TVs in worldwide sales for the first time.<ref>{{Cite news|url=https://www.engadget.com/2008/02/19/worldwide-lcd-tv-shipments-surpass-crts-for-first-time-ever/ |title=Worldwide LCD TV shipments surpass CRTs for first time ever |publisher=engadgetHD |date=February 19, 2008 |access-date=June 13, 2008}}</ref> [[LCD TV]]s were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to [[Displaybank]].<ref>{{Cite news|url=http://www.displaybank.com/eng/info/news/press_show.php?id=2996 |title=Displaybank's Global TV Market Forecasts for 2008 \u2013 Global TV market to surpass 200 million units |publisher=Displaybank |date=December 5, 2007 |access-date=June 13, 2008}}</ref><ref>{{cite web|url=https://technology.ihs.com/389494/ihs-acquires-displaybank-a-global-leader-in-research-and-consulting-in-the-flat-panel-display-industry|title=IHS Acquires Displaybank, a Global Leader in Research and Consulting in the Flat-Panel Display Industry \u2014 IHS Technology|website=technology.ihs.com}}</ref> In October 2011, [[Toshiba]] announced 2560 \u00d7 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a [[tablet computer]],<ref>{{cite web |url=http://www.intomobile.com/2011/10/24/toshiba-announces-61-inch-lcd-panel-insane-resolution-2560-x-1600-pixels/ |title=Toshiba announces 6.1 inch LCD panel with an insane resolution of 2560 x 1600 pixels |date=October 24, 2011 |access-date=October 26, 2011 |archive-url=https://web.archive.org/web/20111026135532/http://www.intomobile.com/2011/10/24/toshiba-announces-61-inch-lcd-panel-insane-resolution-2560-x-1600-pixels/ |archive-date=October 26, 2011 |url-status=dead }}</ref> especially for Chinese character display. The 2010s also saw the wide adoption of TGP (Tracking Gate-line in Pixel), which moves the driving circuitry from the borders of the display to in between the pixels, allowing for narrow bezels.<ref>{{Cite web|url=http://www.cptt.com.tw/cptt/english/index.php?option=com_content&task=view&id=530&Itemid=213|archive-url=https://archive.today/20191223071353/http://www.cptt.com.tw/cptt/english/index.php?option=com_content&task=view&id=530&Itemid=213|url-status=dead|archive-date=December 23, 2019|title=CHUNGHWA PICTURE TUBES, LTD. - intro_Tech|date=December 23, 2019|website=archive.ph}}</ref> LCDs can be made [[See-through display|transparent and flexible]], but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.<ref>{{Cite web|url=https://www.flexenable.com/technology/flexible-olcd/|title=Flexible OLCD | Technology | Flexible Electronics | FlexEnable - FlexEnable|website=www.flexenable.com}}</ref><ref>{{Cite web|url=https://monitorszone.com/4k-curved-gaming-monitors-2020/|title=Transparent LCD Screen | Curved 4k monitors Display Panel|website=Pro Display|access-date=March 18, 2020|archive-date=March 19, 2020|archive-url=https://web.archive.org/web/20200319225809/https://monitorszone.com/4k-curved-gaming-monitors-2020/|url-status=dead}}</ref><ref>{{Cite web|url=https://monitorszone.com/4k-curved-gaming-monitors-2020/|title=UCIC Curved 4k monitors LCD Displays|website=monitorzone|access-date=January 12, 2020|archive-url=https://web.archive.org/web/20200319225809/https://monitorszone.com/4k-curved-gaming-monitors-2020/|archive-date=March 19, 2020|url-status=dead}}</ref><ref>{{Cite web|url=https://www.edn.com/implementing-flexible-oled-and-olcd-display-technologies-in-consumer-electronics/|title=EDN - Implementing flexible OLED and OLCD display technologies in consumer electronics -|date=August 19, 2019}}</ref> Special films can be used to increase the viewing angles of LCDs.<ref>{{Cite web|url=http://and-fujifilm.jp/en/lcd/index.html|title=Illuminating LCD | FUJIFILM | Changing the world, one thing at a time.|website=and-fujifilm.jp}}</ref><ref>{{Cite web|url=https://www.fujifilm.com/about/profile/business_fields/highly_functional_materials/|title=Highly Functional Materials | Fujifilm Global|website=www.fujifilm.com}}</ref>\n\nIn 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.<ref>{{Cite web|url=https://www.cnet.com/news/are-dual-lcds-double-the-fun-new-tv-tech-aims-to-find-out/|title=Are dual-LCDs double the fun? New TV tech aims to find out|first=Geoffrey|last=Morrison|website=CNET}}</ref><ref>{{Cite web|url=https://www.displaydaily.com/article/display-daily/why-is-dual-panel-lcd-vs-oled-a-hot-topic|title=Why is Dual Panel LCD vs OLED a Hot Topic?|first=Bob|last=Raikes|date=July 22, 2019|website=DisplayDaily}}</ref><ref>{{Cite web|url=https://www.techhive.com/article/3505917/hisense-dual-cell-lcd-panel-at-ces-to-compete-with-oled-tech.amp.html|title=Hisense says it has a dual-cell LCD panel at CES that will compete with OLED tech\u2014for a lot less cash | TechHive|website=www.techhive.com}}</ref><ref>{{Cite web|url=https://www.androidauthority.com/panasonic-announces-1000000-contrast-ratio-lcd-733904/|title=Panasonic announces 1,000,000:1 contrast ratio LCD panel to rival OLED|date=December 5, 2016|website=Android Authority}}</ref><ref>{{Cite web|url=https://www.anandtech.com/show/10874/panasonic-develops-ips-panel-with-10000001-contrast-ratio-1000-nits-brightness|title=Panasonic Develops IPS Panel with 1,000,000:1 Contrast Ratio, 1000 Nits Brightness|first=Anton|last=Shilov|website=www.anandtech.com}}</ref><ref>{{Cite web|url=https://www.engadget.com/amp/2016-12-03-panasonic-s-oled-fighting-lcd-is-meant-for-professionals.html|title=Panasonic's OLED-fighting LCD is meant for professionals|website=Engadget}}</ref>"}},
{"article_title": "Leyden jar", "pageid": "18103", "revid": "1054092993", "timestamp": "2021-11-08T01:05:40Z", "history_paths": [["Leyden jar --- Introduction ---", "History"]], "categories": ["electrical instruments", "capacitors", "dielectrics", "dutch inventions", "energy storage", "glass jars", "historical scientific instruments", "science and technology in the dutch republic", "1746 introductions", "18th-century inventions", "german inventions"], "heading_tree": {"Leyden jar --- Introduction ---": {"History": {"Von Kleist": {}, "Musschenbroek and Cunaeus": {}, "Further developments": {}}, "Design": {}, "Storage of the charge": {}, "Quantity of charge": {}, "Residual charge": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Leyden jar --- Introduction ---|History": "[[Image:Andreas Cunaeus discovering the Leyden jar.png|thumb|upright=1.8|Discovery of the Leyden jar in Musschenbroek's lab.  The static electricity produced by the rotating glass sphere [[electrostatic generator]] was conducted by the chain through the suspended bar to the water in the glass held by assistant Andreas Cunaeus. A large charge accumulated in the water and an opposite charge in Cunaeus' hand on the glass.  When he touched the wire dipping in the water, he received a powerful shock. ]]\n[[File:Leidse flessen Museum Boerhave december 2003 2.jpg|thumb|upright|A [[battery (electricity)|battery]] of four water-filled Leyden jars, [[Museum Boerhaave]], Leiden]]\n\nThe [[Ancient Greeks]] already knew that pieces of [[amber]] could attract lightweight particles after being rubbed. The amber becomes electrified by [[triboelectric effect]],{{efn|The prefix ''tribo-'' (Greek for \u2018rub\u2019) refers to \u2018friction\u2019}} mechanical separation of charge in a [[dielectric]]. The Greek word for amber is \u1f24\u03bb\u03b5\u03ba\u03c4\u03c1\u03bf\u03bd ("\u0113lektron") and is the origin of the word "electricity".<ref>{{cite web|title=electric|url=https://www.merriam-webster.com/dictionary/electric|website=Merriam-Webster|access-date=12 May 2017|quote=Origin and Etymology of ''electric'': New Latin ''electricus'' 'produced from amber by friction, electric', from Medieval Latin, 'of amber', from Latin ''electrum'' 'amber, electrum', from Greek ''\u0113lektron''; akin to Greek ''\u0113lekt\u014dr'' 'beaming sun'. First Known Use: 1722}}</ref> Thales of Miletus, a pre-Socratic philosopher is thought to have accidentally commented on the phenomena of electrostatic charging, due to his belief that even lifeless things have a soul in them, hence the popular analogy of the spark.<ref>Iverson, Paul. 2012. A life of its own: The tenuous connection between Thales of Miletus and the study of electrostatic charging. Journal of Electrostatics. Volume 70, Issue 3, June 2012, Pages 309-311 </ref>  \n\nAround 1650, [[Otto von Guericke]] built a crude [[electrostatic generator]]: a [[sulfur|sulphur]] ball that rotated on a shaft. When Guericke held his hand against the ball and turned the shaft quickly, a static [[electric charge]] built up. This experiment inspired the development of several forms of "friction machines", that greatly helped in the study of electricity.\n\nThe Leyden jar was effectively discovered independently by two parties: German deacon [[Ewald Georg von Kleist]], who made the first discovery, and Dutch scientists [[Pieter van Musschenbroek]] and Andreas Cunaeus, who figured out how it worked only when held in the hand.<ref>{{Gutenberg |bullet=none |no=5641 |name=Man or Matter |first=Ernst |last=Lehrs |accessdate=2017-05-12 |authorlink=Ernst Lehrs |origyear=1951 |publisher=Klostermann |year=1953 |edition=3rd  |ISBN= 3-465-00285-7}}</ref>\n\nThe Leyden jar is a high voltage device; it is estimated that at a maximum the early Leyden jars could be charged to 20,000 to 60,000 volts.<ref>{{cite journal |last1=Anders |first1=A. |title=Tracking down the origin of arc plasma science I. Early pulsed and oscillating discharges |journal=IEEE Transactions on Plasma Science |date=2003 |volume=31 |issue=5 |page=1056 |doi=10.1109/tps.2003.815476|bibcode=2003ITPS...31.1052A |url=https://digital.library.unt.edu/ark:/67531/metadc785933/ |type=Submitted manuscript }}</ref> The center rod electrode has a metal ball on the end to prevent leakage of the charge into the air by [[corona discharge]].  It was first used in [[electrostatics]] experiments, and later in high voltage equipment such as [[spark gap transmitter|spark gap radio transmitter]]s and [[electrotherapy]] machines. \n\n [[Ewald Georg von Kleist]] discovered the immense storage capability of the Leyden jar while working under a theory that saw electricity as a fluid, and hoped a glass jar filled with alcohol would "capture" this fluid.<ref>Thomas S. Kuhn, ''The Structure of Scientific Revolutions'' (Chicago, Illinois: University of Chicago Press, 1996) p. 17.</ref> He was the deacon at the cathedral of Camin in Pomerania.\n\nIn October 1745 von Kleist tried to accumulate electricity in a small medicine bottle filled with alcohol with a nail inserted in the cork. He was following up on an experiment developed by [[Georg Matthias Bose]] where electricity had been sent through water to set alcoholic spirits alight. He attempted to charge the bottle from a large prime conductor (invented by Bose) suspended above his friction machine.\n\nKleist was convinced that a substantial electric charge could be collected and held within the glass which he knew would provide an obstacle to the escape of the 'fluid'. He received a significant shock from the device when he accidentally touched the nail through the cork while still cradling the bottle in his other hand. He communicated his results to at least five different electrical experimenters,<ref>{{Cite book | last = Heilbron| first = J.L.| author-link=John L. Heilbron | title = Electricity in the 17th and 18th Centuries: A Study of Early Modern Physics|publisher = [[University of California Press]]|year = 1979|page = 311|isbn= 978-0-520-03478-5|url= https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA311}}</ref> in several letters from November 1745 to March 1746, but did not receive any confirmation that they had repeated his results, until April 1746.<ref>{{cite journal|last1=Silva|first1=C.S.|last2=Heering|first2=P. | title=Re-examining the early history of the Leiden jar: Stabilization and variation in transforming a phenomenon into a fact| journal=History of Science|volume=56|issue=3|pages=314\u2013342| date=2018| doi=10.1177/0073275318768418|pmid=29683000|s2cid=5112189}}</ref> [[Daniel Gralath]] learned about Kleist's experiment from seeing the letter to Paul Swietlicki, written in November 1745. After Gralath's failed first attempt to reproduce the experiment in December 1745, he wrote to Kleist for more information (and was told that the experiment would work better if the tube half-filled with alcohol was used). Gralath (in collaboration with {{ill |Gottfried Reyger|de}}) succeeded in getting the intended effect on 5 March 1746, holding a small glass medicine bottle with a nail inside in one hand, moving it close to an electrostatic generator, and then moving the other hand close to the nail.<ref>{{cite journal|last1=Silva|first1=C.S.|last2=Heering|first2=P. | title=Re-examining the early history of the Leiden jar: Stabilization and variation in transforming a phenomenon into a fact| journal=History of Science|volume=56|issue=3|pages=314\u2013342| date=2018| doi=10.1177/0073275318768418 |pmid=29683000|s2cid=5112189}}</ref> Kleist didn't understand the significance of his conducting hand holding the bottle\u2014and both he and his correspondents were loath to hold the device when told that the shock could throw them across the room. It took some time before Kleist's student associates at Leyden worked out that the hand provided an essential element.{{cn|date=May 2018|reason=Kleist did not have student associates in Leiden}}\n\n {{refimprove section|date=July 2016}}\nThe Leyden jar's invention was long credited to [[Pieter van Musschenbroek]], the physics professor at [[University of Leiden]], who also ran a family foundry which cast brass cannonettes, and a small business (''De Oosterse Lamp'' \u2013 "The Eastern Lamp") which made scientific and medical instruments for the new university courses in physics and for scientific gentlemen keen to establish their own [[cabinet of curiosities|'cabinets' of curiosities and instruments]].\n\nEwald Kleist is credited with first using the fluid analogy for electricity and demonstrated this to Bose by drawing sparks from water with his finger.<ref>Sela, Andrea. 28 March 2017. Von Kleist's jar. Chemistry World, Royal Society of Chemistry 2021.</ref>\n\nLike Kleist, Musschenbroek was also interested in and attempting to repeat Bose's experiment.<ref>{{cite journal|last1=Heilbron|first1=John L.|author-link=John L. Heilbron |title=G. M. Bose: The prime mover in the invention of the Leyden jar?|journal=Isis|date=1966|volume=57|issue=2|pages=264\u2013267|jstor=227966|doi=10.1086/350120|s2cid=144694754}}</ref> During this time, Andreas Cunaeus, a lawyer, came to learn about this experiment from visiting Musschenbroek's laboratory and Cunaeus attempted to duplicate the experiment at home with household items.<ref>{{cite book  |title=Electricity in the 17th and 18th centuries: a study of early Modern physics |last=Heilbron |author-link=John L. Heilbron  |first=J.L. |year=1979 |publisher=[[University of California Press]] |isbn=978-0-520-03478-5 |page=313 |url=https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA313}}</ref> Using a glass of beer,{{cn|reason=water, not beer mentioned in Heilbron|date=April 2018}} Cunaeus was unable to make it work.{{cn|reason=Heilbron, p. 313 reports success|date=April 2018}}  \n\nCunaeus was the first to discover that such an experimental setup could deliver a severe shock when he held his jar in his hand while charging it rather than placing it on an insulated stand, not realizing that was the standard practice, thus making himself part of the circuit.<ref>Van Rogan A. An overview of dielectric measurements\nMarch 1990IEEE Transactions on Electrical Insulation 25(1):95 - 106.</ref> He reported his procedure and experience to [[Jean-Nicolas-S\u00e9bastien Allamand|Allamand]], Musschenbroek's colleague.  Allamand  and Musschenbroek also received severe shocks.  Musschenbroek communicated the experiment in a letter from 20 January 1746 to [[Ren\u00e9 Antoine Ferchault de R\u00e9aumur]],  who was Musschenbroek's appointed correspondent at the Paris Academy. [[Jean-Antoine Nollet|Abb\u00e9 Nollet]] read this report, confirmed the experiment, and then read Musschenbroek's letter in a public meeting of the Paris Academy in April 1746<ref>{{cite book  |title=Electricity in the 17th and 18th centuries: a study of early Modern physics |last=Heilbron |author-link=John L. Heilbron  |first=J.L. |year=1979 |publisher=[[University of California Press]] |isbn=978-0-520-03478-5 |pages=313\u2013314 |url=https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA313}}</ref> (translating from Latin to French).<ref> Here is Nollet's own account of the event. [http://gallica.bnf.fr/ark:/12148/bpt6k35444/f140 Observations sur quelques nouveaux ph\u00e9nom\u00e8nes d'\u00c9lectricit\u00e9]" ''M\u00e9moires de l' Acad\u00e9mie Royale des Sciences De l'Ann\u00e9e 1746'', Paris, 1751, pp. 1\u20133. The account from the Academy of Sciences only refers to the "Leyden experiment" (''l'exp\u00e9rience de Leyde''):  [https://www.biodiversitylibrary.org/item/87779#page/13/mode/1up Sur l'\u00c9lectricit\u00e9]" ''Histoire de l' Acad\u00e9mie Royale des Sciences De l'Ann\u00e9e 1746'', Paris, 1751, pp. 1\u201317.</ref>\n\nMusschenbroek's outlet in France for the sale of his company's  'cabinet' devices was the Abb\u00e9 Nollet (who started building and selling duplicate instruments in 1735<ref>{{cite encyclopedia|title=Nollet, Jean-Antoine|edition=2nd | date=2000 | publisher=Charles Scribner's Sons |work=Concise dictionary of scientific biography |page=652| url=https://archive.org/stream/concisedictionar00#page/652/mode/2up}}</ref>).  Nollet then gave the electrical storage device the name "Leyden jar" and promoted it as a special type of flask to his market of wealthy men with scientific curiosity.\nThe "Kleistian jar" was therefore promoted as the ''Leyden jar'', and as having been discovered by [[Pieter van Musschenbroek]] and his acquaintance Andreas Cunaeus.  Musschenbroek, however, never claimed that he had invented it,<ref>{{cite book  |title=Electricity in the 17th and 18th centuries: a study of early Modern physics |last=Heilbron |author-link=John L. Heilbron  |first=J.L. |year=1979 |publisher=[[University of California Press]] |isbn=978-0-520-03478-5 |page=314, fn. 18|url=https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA314}}</ref> and some think that Cunaeus was mentioned only to diminish credit to him.<ref>{{cite book|last1=Benjamin|first1=P. | author-link= Park Benjamin Jr.|title=A History of Electricity: the intellectual rise in electricity |date=1898|publisher=Wiley|page=521|url=https://archive.org/stream/cu31924004128686#page/n533/mode/2up/}} and {{cite book|last1=Abb\u00e9 de Mangin|title=Histoire g\u00e9n\u00e9rale et particuliere de l'\u00e9lectricit\u00e9|date=1752|publisher=Chez Rollin|page=30|url=https://archive.org/stream/histoiregnralee01manggoog#page/n48/mode/2up/}}</ref>\n\n Within months after Musschenbroek's report about how to reliably create a Leyden jar, other electrical researchers were making and experimenting with their own Leyden jars.<ref>{{cite book|last1=Priestley|first1=Joseph|title=The History and Present State of Electricity, with original experiments|date=1775|location=London|pages=108|edition=3rd|url=https://archive.org/stream/historyandprese00priegoog#page/n154/mode/2up/|access-date=25 April 2018|publisher=London : Printed for C. Bathurst, and T. Lowndes ... J. Rivington, and J. Johnson ... S. Crowder, G. Robinson, and R. Baldwin ... T. Becket, and T. Cadell ...}}</ref> One of his expressed original interests was to see if the total possible charge could be increased.<ref>Godoy, Luis & Elishakoff, Isaac. (2020). The Experimental Contribution of Petrus Van Musschenbroek to the Discovery of a Buckling Formula in the Early 18th Century. International Journal of Structural Stability and Dynamics.</ref>\n\n[[Johann Heinrich Winckler]], whose first experience with a single Leyden jar was reported in a letter to the [[Royal Society]] on 29 May 1746, had connected three Leyden jars together in a kind of electrostatic battery on 28 July 1746.<ref name=Allerhand>{{cite journal|last1=Allerhand|first1=A.|title=Who invented the earliest capacitor bank ("battery" of Leyden jars)? It's complicated|journal=[[Proceedings of the IEEE]] |date=2018 |volume=106 |issue=3|pages=498\u2013500|doi=10.1109/JPROC.2018.2795846}}</ref> In 1746, [[Abb\u00e9 Nollet]] performed two experiments for the edification of [[King Louis XV]] of France, in the first of which he discharged a Leyden jar through 180 [[Maison Militaire du Roi de France|royal guardsmen]], and in the second through a larger number of [[Carthusian monks]]; all of whom sprang into the air more or less simultaneously. The opinions of neither the king nor the experimental subjects have been recorded.<ref>{{cite book |title=[[The History and Present State of Electricity]] |first=Joseph |last=Priestley |author-link=Joseph Priestley |year=1769}}</ref>{{page needed|date=August 2021}} [[Daniel Gralath]] reported in 1747 that in 1746 he had conducted experiments with connecting two or three jars, probably in [[Series and parallel circuits#Series circuits|series]].<ref name=Allerhand /> In 1746-1748, [[Benjamin Franklin]] experimented with charging Leyden jars in series,<ref>{{EB1911|noprescript=1|wstitle=Leyden Jar |volume=16 |page=528}}</ref> and developed a system involving 11 panes of glass with thin lead plates glued on each side, and then connected together. He used the term "electrical battery" to describe his electrostatic battery in a 1749 letter about his electrical research in 1748.<ref>Benjamin Franklin (1961). [https://franklinpapers.org/framedVolumes.jsp?vol=3&page=352a To Peter Collinson, April 29, 1749] {{Webarchive|url=https://web.archive.org/web/20171217065533/http://franklinpapers.org/franklin/framedVolumes.jsp?vol=3&page=352a |date=December 17, 2017 }}. In Leonard W. Labaree, ed., ''The Papers of Benjamin Franklin'' vol. 3: 1745\u20131750. New Haven: Yale University Press,  p. 352: \u00a718.\nFor a discussion of the significance of this and other Franklin letters and how they express Franklin's explanation of "Muschenbroek\u2019s wonderful bottle" see: {{cite book|last1=Kuehn|first1=K| work=A student's guide through the great physics texts. Volume III. Electricity, magnetism and light|date=2016|publisher=Springer |title=M\u00fcschenbroek's Wonderful Bottle |isbn=978-3319218168 |pages=43\u201360| doi=10.1007/978-3-319-21816-8_4|series=Undergraduate Lecture Notes in Physics}}</ref> It is possible that Franklin's choice of the word ''battery'' was inspired by the humorous wordplay at the conclusion of his letter, where he wrote, among other things, about a salute to electrical researchers from a battery of [[cannon|guns]].<ref>{{cite web |author = Benjamin Franklin |title = To Peter Collinson, April 29, 1749 |url = https://franklinpapers.org/framedVolumes.jsp?vol=3&page=352a |access-date = July 19, 2012 |archive-url = https://web.archive.org/web/20171217065533/http://franklinpapers.org/franklin/framedVolumes.jsp?vol=3&page=352a |archive-date = December 17, 2017 |url-status = dead }}\n"Chagrin\u2019d a little that We have hitherto been able to discover Nothing in this Way of Use to Mankind, and the hot Weather coming on, when Electrical Experiments are not so agreable; \u2019tis proposed to put an End to them for this Season somewhat humorously in a Party of Pleasure on the Banks of SchuylKill, (where Spirits are at the same Time to be fired by a Spark sent from Side to Side thro\u2019 the River). A Turky is to be killed for our Dinners by the Electrical Shock; and roasted by the electrical Jack, before a Fire kindled by the Electrified Bottle; when the Healths of all the Famous Electricians in England, France and Germany, are to be drank in Electrified Bumpers, under the Discharge of Guns from the Electrical Battery." \u00a729.</ref> This is the first recorded use of the term ''electrical battery''.<ref name=Allerhand /> The multiple and rapid developments for connecting Leyden jars during the period 1746\u20131748 resulted in a variety of divergent accounts in secondary literature about who made the first "battery" by connecting Leyden jars, whether they were in series or parallel, and who first used the term "battery".<ref name=Allerhand /> The term was later used for combinations of multiple electrochemical cells, the modern meaning of the term "battery".\n\nThe Swedish physicist, chemist and meteorologist, Tobern Bergman translated much of Benjamin Franklin's writings on electricity into German and continued to study electrostatic properties.<ref>Muller-Hillebrand, D. "Torbern Bergman as a Lightening Scientist." A Bicentenary Memorial of Swedish Lightning Research in the Context of 18th-century Electrical Discoveries. Upsalla University. 42 pages, Pg. 6. Published 1964.</ref>\n\nStarting in late 1756, [[Franz Aepinus]], in a complicated interaction of cooperation and independent work with [[Johan Wilcke]],<ref>{{cite encyclopedia |last1=Home |first1=R.W.| work=Aepinus's Essay on the Theory of Electricity and Magnetism|date=2015|publisher=[[ Princeton University Press]]|title=The Electrical Background|isbn=978-1-4008-6952-7|orig-year=1979|pages=89\u201392}}</ref> developed an "air condenser", a variation on the Leyden jar, by using air rather than glass as the dielectric.  This functioning apparatus, without glass, created a problem for Benjamin Franklin's explanation of the Leyden jar, which maintained that the charge was located in the glass.<ref>{{Cite book | last = Heilbron| first = J.L.| author-link=John L. Heilbron | title = Electricity in the 17th and 18th Centuries: A Study of Early Modern Physics| publisher = [[University of California Press]]|year = 1979|page = 388|isbn= 978-0-520-03478-5|url= https://books.google.com/books?id=UlTLRUn1sy8C&pg=PA388}}</ref>\n\nBeginning in the late 18th century it was used in the Victorian medical field of [[electrotherapy]] to treat a variety of diseases by electric shock.   By the middle of the 19th century, the Leyden jar had become common enough for writers to assume their readers knew of and understood its basic operation.{{Citation needed|date=December 2011}}  Around the turn of the century it began to be widely used in [[spark-gap transmitter]]s and medical [[electrotherapy]] equipment. By the early 20th century, improved dielectrics and the need to reduce their size and undesired [[inductance]] and [[Electrical resistance|resistance]] for use in the new technology of [[radio]] caused the Leyden jar to evolve into the modern compact form of [[capacitor]]."}},
{"article_title": "Light-emitting diode", "pageid": "18290", "revid": "1061861349", "timestamp": "2021-12-24T13:20:16Z", "history_paths": [["Light-emitting diode --- Introduction ---", "History"]], "categories": ["light-emitting diodes", "led lamps", "optical diodes", "display technology", "signage", "20th-century inventions", "japanese inventions"], "heading_tree": {"Light-emitting diode --- Introduction ---": {"History": {"Discoveries and early devices": {}, "Initial commercial development": {}, "Blue LED": {}, "White LEDs and the illumination breakthrough": {}}, "Physics of light production and emission": {}, "Colors": {"Blue and ultraviolet": {}, "White": {"RGB systems": {}, "Phosphor-based LEDs": {}, "Other white LEDs": {}}}, "Organic light-emitting diodes (OLEDs)": {}, "Types": {"Miniature": {}, "High-power": {}, "AC-driven": {}, "Application-specific variations": {"Flashing": {}, "Bi-color": {}, "RGB tri-color": {}, "Decorative-multicolor": {}, "Alphanumeric": {}, "Digital RGB": {}, "Filament": {}, "Chip-on-board arrays": {}}}, "Considerations for use": {"Power sources": {}, "Electrical polarity": {}, "Safety and health": {}, "Advantages": {}, "Disadvantages": {}}, "Applications": {"Indicators and signs": {}, "Lighting": {}, "Data communication and other signalling": {}, "Machine vision systems": {}, "Biological detection": {}, "Other applications": {}}, "Research and development": {"Key challenges": {}, "Potential technology": {"Perovskite LEDs (PLEDs)": {}}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Light-emitting diode --- Introduction ---|History": "[[File:SiC LED historic.jpg|thumb|Green electroluminescence from a point contact on a crystal of [[silicon carbide|SiC]] recreates [[H. J. Round|Round]]'s original experiment from 1907.]]\n\n[[Electroluminescence]] as a phenomenon was discovered in 1907 by the English experimenter [[H. J. Round]] of [[Marconi Company|Marconi Labs]], using a crystal of [[silicon carbide]] and a [[cat's-whisker detector]].<ref>{{Cite journal|author=Round, H. J.|year=1907|title=A note on carborundum|journal=Electrical World|volume=19|page=309|url=https://books.google.com/books?id=TAZRAAAAYAAJ&pg=PA309}}</ref><ref>{{cite web|url=http://www.jmargolin.com/history/trans.htm|author=Margolin J|website=jmargolin.com|title=''The Road to the Transistor''}}</ref> Russian inventor [[Oleg Losev]] reported creation of the first LED in 1927.<ref name="Losev1927">{{cite journal|last1=Losev|first1=O. V.|title=\u0421\u0432\u0435\u0442\u044f\u0449\u0438\u0439\u0441\u044f \u043a\u0430\u0440\u0431\u043e\u0440\u0443\u043d\u0434\u043e\u0432\u044b\u0439 \u0434\u0435\u0442\u0435\u043a\u0442\u043e\u0440 \u0438 \u0434\u0435\u0442\u0435\u043a\u0442\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0441 \u043a\u0440\u0438\u0441\u0442\u0430\u043b\u043b\u0430\u043c\u0438|journal=\u0422\u0435\u043b\u0435\u0433\u0440\u0430\u0444\u0438\u044f \u0438 \u0422\u0435\u043b\u0435\u0444\u043e\u043d\u0438\u044f \u0431\u0435\u0437 \u041f\u0440\u043e\u0432\u043e\u0434\u043e\u0432 [Wireless Telegraphy and Telephony]|date=1927|volume=5|issue=44|pages=485\u2013494|trans-title=Luminous carborundum detector and detection with crystals|language=ru}} English translation:  {{cite journal|last1=Losev|first1=O. V.|title=Luminous carborundum detector and detection effect and oscillations with crystals|journal=Philosophical Magazine|date=November 1928|volume=5|issue=39|pages=1024\u20131044|doi=10.1080/14786441108564683|series=7th series}}</ref> His research was distributed in Soviet, German and British scientific journals, but no practical use was made of the discovery for several decades.<ref name="Zheludev_100yearhistory">{{Cite journal |author = Zheludev, N. |year = 2007 |title = The life and times of the LED: a 100-year history |journal = Nature Photonics |volume = 1 |issue = 4 |pages = 189\u2013192 |url = http://www.nanophotonics.org.uk/niz/publications/zheludev-2007-ltl.pdf |doi = 10.1038/nphoton.2007.34 |bibcode = 2007NaPho...1..189Z |access-date = April 11, 2007 |archive-url = https://web.archive.org/web/20110511132457/http://www.nanophotonics.org.uk/niz/publications/zheludev-2007-ltl.pdf |archive-date = May 11, 2011 |url-status     = dead |df = mdy-all}}</ref><ref>{{cite book|author=Lee, Thomas H. |title=The design of CMOS radio-frequency integrated circuits|url=https://archive.org/details/designcmosradiof00leet_307 |url-access=limited |publisher=[[Cambridge University Press]]|year=2004|isbn=978-0-521-83539-8|page=[https://archive.org/details/designcmosradiof00leet_307/page/n18 20]}}</ref>\n \nIn 1936, [[Georges Destriau]] observed that electroluminescence could be produced when [[zinc sulphide]] (ZnS) powder is suspended in an insulator and an alternating electrical field is applied to it. In his publications, Destriau often referred to luminescence as Losev-Light. Destriau worked in the laboratories of Madame [[Marie Curie]], also an early pioneer in the field of luminescence with research on [[radium]].<ref name="ChemiePhysique">{{Cite journal|author=Destriau, G.|year=1936|title=Recherches sur les scintillations des sulfures de zinc aux rayons|journal=Journal de Chimie Physique|volume=33|pages=587\u2013625|doi=10.1051/jcp/1936330587\n}}</ref><ref name="ConciseEncyclopediaOfPhysics">McGraw-Hill Concise Encyclopedia of Physics: electroluminescence. (n.d.) McGraw-Hill Concise Encyclopedia of Physics. (2002).</ref>\n\nHungarian [[Zolt\u00e1n Bay]]  together with [[Gy\u00f6rgy Szigeti]]  pre-empted [[LED lighting]] in Hungary in 1939 by patenting a lighting device based on SiC, with an option on boron carbide, that emitted white, yellowish white, or greenish white depending on impurities present.<ref>{{Cite web|url=https://www.iitk.ac.in/solarlighting/files/brief_history_of_LEDs.pdf|title=Brief history of LEDs}}</ref>\n\n[[Kurt Lehovec]], Carl Accardo, and Edward Jamgochian explained these first LEDs in 1951 using an apparatus employing [[silicon carbide|SiC]] crystals with a current source of a battery or a pulse generator and with a comparison to a variant, pure, crystal in 1953.<ref>{{Cite journal|year=1951|title=Injected Light Emission of Silicon Carbide Crystals|journal=Physical Review|volume=83|issue=3|pages=603\u2013607|url=http://www.campevans.org/_CE/html/tpr-08-01-1951p604-lehovec.html|doi=10.1103/PhysRev.83.603|url-status=dead|archive-url=https://web.archive.org/web/20141211015103/http://www.campevans.org/_CE/html/tpr-08-01-1951p604-lehovec.html|archive-date=December 11, 2014|df=mdy-all|bibcode=1951PhRv...83..603L|last1=Lehovec|first1=K|last2=Accardo|first2=C. A|last3=Jamgochian|first3=E}}</ref><ref>{{Cite journal|year=1953|title=Injected Light Emission of Silicon Carbide Crystals|journal=Physical Review|volume=89|issue=1|pages=20\u201325|doi=10.1103/PhysRev.89.20|bibcode=1953PhRv...89...20L|last1=Lehovec|first1=K|last2=Accardo|first2=C. A|last3=Jamgochian|first3=E}}</ref>\n\n[[Rubin Braunstein]]<ref>{{cite web |url=http://personnel.physics.ucla.edu/directory/faculty/braunstein/ |title=Rubin Braunstein |publisher=UCLA |archive-url=https://web.archive.org/web/20110311150933/http://personnel.physics.ucla.edu/directory/faculty/braunstein |archive-date=March 11, 2011 |access-date=January 24, 2012 |url-status=dead }}</ref> of the [[Radio Corporation of America]] reported on infrared emission from [[gallium arsenide]] (GaAs) and other semiconductor alloys in 1955.<ref>{{Cite journal|author=Braunstein, Rubin\n|year=1955 |title=Radiative Transitions in Semiconductors |journal=Physical Review|volume=99|pages=1892\u20131893 |doi=10.1103/PhysRev.99.1892 |issue=6 |bibcode = 1955PhRv...99.1892B }}</ref> Braunstein observed infrared emission generated by simple diode structures using [[gallium antimonide]] (GaSb), GaAs, [[indium phosphide]] (InP), and [[silicon-germanium]] (SiGe) alloys at room temperature and at 77 [[kelvin]]s<!-- lower-case and pluralized! See Kelvin#Usage_conventions -->.\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance.  As noted by Kroemer<ref>{{cite journal |last1=Kroemer |first1=Herbert |title=The Double-Heterostructure Concept: How It Got Started |journal=Proceedings of the IEEE|date=Sep 16, 2013 |volume=101 |issue=10 |pages=2183\u20132187 |doi=10.1109/JPROC.2013.2274914|s2cid=2554978 }}</ref> Braunstein "\u2026had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics to modulate the forward current of a GaAs diode. The emitted light was detected by a PbS diode some distance away. This signal was fed into an audio amplifier and played back by a loudspeaker. Intercepting the beam stopped the music. We had a great deal of fun playing with this setup." This setup presaged the use of LEDs for [[optical communication]] applications.\n\n[[File:SNX100.jpg|thumb|A 1962 Texas Instruments SNX-100 GaAs LED contained in a TO-18 transistor metal case]]\n\nIn September 1961, while working at [[Texas Instruments]] in [[Dallas]], [[Texas]], [[James R. Biard]] and Gary Pittman discovered near-infrared (900 nm) light emission from a [[tunnel diode]] they had constructed on a GaAs substrate.<ref name=FirstPracticalLED>{{cite web|author1=Okon, Thomas M. |author2=Biard, James R. |title=The First Practical LED|url=http://edisontechcenter.org/lighting/LED/TheFirstPracticalLED.pdf|website=EdisonTechCenter.org|publisher=[[Edison Tech Center]]|date=2015|access-date=2016-02-02}}</ref> By October 1961, they had demonstrated efficient light emission and signal coupling between a GaAs p-n junction light emitter and an electrically isolated semiconductor photodetector.<ref>Matzen, W. T. ed. (March 1963) [http://www.dtic.mil/dtic/tr/fulltext/u2/411614.pdf "Semiconductor Single-Crystal Circuit Development,"] Texas Instruments Inc., Contract No. AF33(616)-6600, Rept. No ASD-TDR-63-281.</ref> On August 8, 1962, Biard and Pittman filed a patent titled "Semiconductor Radiant Diode" based on their findings, which described a zinc-diffused [[p\u2013n junction]] LED with a spaced [[cathode]] contact to allow for efficient emission of infrared light under [[forward bias]]. After establishing the priority of their work based on engineering notebooks predating submissions from [[G.E.]] Labs, [[RCA]] Research Labs, [[IBM]] Research Labs, [[Bell Labs]], and [[Lincoln Lab]] at [[MIT]], the [[United States Patent and Trademark Office|U.S. patent office]] issued the two inventors the patent for the GaAs infrared light-emitting diode (U.S. Patent [http://www.freepatentsonline.com/3293513.pdf US3293513]), the first practical LED.<ref name=FirstPracticalLED /> Immediately after filing the patent, [[Texas Instruments]] (TI) began a project to manufacture infrared diodes. In October 1962, TI announced the first commercial LED product (the SNX-100), which employed a pure GaAs crystal to emit an 890 nm light output.<ref name=FirstPracticalLED /> In October 1963, TI announced the first commercial hemispherical LED, the SNX-110.<ref>{{cite journal| title=One-watt GaAs p-n junction infrared source |author1=Carr, W. N.  |author2=G. E. Pittman | journal=Applied Physics Letters |date=November 1963 | volume=3 | issue=10 | pages = 173\u2013175 | doi=10.1063/1.1753837|bibcode=1963ApPhL...3..173C }}</ref>\n\nThe first visible-spectrum (red) LED was demonstrated by J W Allen and R J Cherry in late 1961 at the SERL in Baldock, UK. This work was reported in Journal of Physics and Chemistry of Solids\nVolume 23, Issue 5, May 1962, Pages 509\u2013511. Another early device was demonstrated by [[Nick Holonyak|Nick Holonyak, Jr.]] on October 9, 1962, while he was working for [[General Electric]] in [[Syracuse, New York]].<ref>{{cite web |title=Nick Holonyak, Jr., six decades in pursuit of light |date=May 4, 2012 |last=Kubetz |first=Rick |publisher=University of Illinois |url=https://grainger.illinois.edu/news/2012-05-04-nick-holonyak-jr-six-decades-pursuit-light |access-date=2020-07-07}}</ref> Holonyak and Bevacqua reported this LED in the journal ''Applied Physics Letters'' on December 1, 1962.<ref>{{cite journal | url=http://apl.aip.org/resource/1/applab/v1/i4 | title=Coherent (Visible) Light Emission from Ga(As<sub>1\u2212x</sub> P<sub>x</sub>) Junctions | author=Holonyak Nick | journal=Applied Physics Letters | date=December 1962 | issue=4 | doi=10.1063/1.1753706 | last2=Bevacqua | first2=S. F. | volume=1 | page=82 | bibcode=1962ApPhL...1...82H | url-status=dead | archive-url=https://web.archive.org/web/20121014035733/http://apl.aip.org/resource/1/applab/v1/i4 | archive-date=October 14, 2012 | df=mdy-all }}</ref><ref name="chisuntimes">{{cite news| title = U. of I.'s Holonyak out to take some of Edison's luster| author = Wolinsky, Howard| date = February 5, 2005| url = http://findarticles.com/p/articles/mi_qn4155/is_20050202/ai_n9504926| archive-url = https://web.archive.org/web/20060328001535/http://findarticles.com/p/articles/mi_qn4155/is_20050202/ai_n9504926| url-status = dead| archive-date = March 28, 2006| newspaper = Chicago Sun-Times| access-date = July 29, 2007 }}</ref> [[M. George Craford]],<ref>{{Cite journal |year=1995 |volume=32 |pages= 52\u201355 |doi=10.1109/6.343989 |title=M. George Craford [biography] |last1=Perry |first1=T. S. |journal=IEEE Spectrum| issue=2}}</ref> a former graduate student of Holonyak, invented the first yellow LED and improved the brightness of red and red-orange LEDs by a factor of ten in 1972.<ref>{{cite web|url=http://www.technology.gov/Medal/2002/bios/Holonyak_Craford_Dupuis.pdf|title=Brief Biography \u2014 Holonyak, Craford, Dupuis|publisher=Technology Administration|access-date=May 30, 2007|url-status=dead|archive-url=https://web.archive.org/web/20070809062214/http://www.technology.gov/Medal/2002/bios/Holonyak_Craford_Dupuis.pdf|archive-date=August 9, 2007|df=mdy-all}}</ref> In 1976, T. P. Pearsall designed the first high-brightness, high-efficiency LEDs for optical fiber telecommunications by inventing new semiconductor materials specifically adapted to optical fiber transmission wavelengths.<ref>{{Cite journal |title=Efficient, Lattice-matched, Double Heterostructure LEDs at 1.1 mm from Ga<sub>''x''</sub>In<sub>1\u2212''x''</sub>As<sub>''y''</sub>P<sub>1\u2212''y''</sub> by Liquid-phase Epitaxy |journal=Appl. Phys. Lett. |volume=28 |page=499 |year=1976 |doi=10.1063/1.88831 |last1=Pearsall |first1=T. P. |last2=Miller |first2=B. I. |last3=Capik |first3=R. J. |last4=Bachmann |first4=K. J. |issue=9 |bibcode = 1976ApPhL..28..499P }}</ref>\n\n The first commercial visible-wavelength LEDs were commonly used as replacements for [[incandescence|incandescent]] and [[neon lamp|neon indicator lamps]], and in [[seven-segment display]]s,<ref>{{cite journal | url=http://www.datamath.org/Display/Monsanto.htm | title=LEDs cast Monsanto in Unfamiliar Role | author=Rostky, George | journal=Electronic Engineering Times |date=March 1997 | issue=944}}</ref> first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as calculators, TVs, radios, telephones,  as well as watches (see list of [[#Indicators and signs|signal uses]]).\nUntil 1968, visible and infrared LEDs were extremely costly, in the order of [[United States dollar|US$]]200 per unit, and so had little practical use.<ref name="Schubert" />\n\n[[Hewlett-Packard]] (HP) was engaged in [[research and development]] (R&D) on practical LEDs between 1962 and 1968, by a research team under Howard C. Borden, Gerald P. Pighini and [[Mohamed M. Atalla]] at HP Associates and [[HP Labs]].<ref name="Borden">{{cite journal |last1=Borden |first1=Howard C. |last2=Pighini |first2=Gerald P. |title=Solid-State Displays |journal=[[Hewlett-Packard Journal]] |date=February 1969 |pages=2\u201312 |url=http://hparchive.com/Journals/HPJ-1969-02.pdf}}</ref> During this time, Atalla launched a material science investigation program on [[gallium arsenide]] (GaAs), [[gallium arsenide phosphide]] (GaAsP) and [[indium arsenide]] (InAs) devices at HP,<ref>{{cite book |last1=House |first1=Charles H. |last2=Price |first2=Raymond L. |title=The HP Phenomenon: Innovation and Business Transformation |date=2009 |publisher=[[Stanford University Press]] |isbn=9780804772617 |pages=110\u20131 |url=https://books.google.com/books?id=OsTnDv6d2DwC&pg=PA110}}</ref> and they collaborated with [[Monsanto Company]] on developing the first usable LED products.<ref name="Kramer">{{cite book |last1=Kramer |first1=Bernhard |title=Advances in Solid State Physics |date=2003 |publisher=[[Springer Science & Business Media]] |isbn=9783540401506 |page=40 |url=https://books.google.com/books?id=oREQToB2q2UC&pg=PA40}}</ref> The first usable LED products were HP's [[LED display]] and Monsanto's [[LED lamp|LED indicator lamp]], both launched in 1968.<ref name="Kramer"/> Monsanto was the first organization to mass-produce visible LEDs, using GaAsP in 1968 to produce red LEDs suitable for indicators.<ref name="Schubert">{{Cite book|author=Schubert, E. Fred |title=Light-Emitting Diodes|publisher=Cambridge University Press|year=2003|chapter=1|isbn=978-0-8194-3956-7}}</ref> Monsanto had previously offered to supply HP with GaAsP, but HP decided to grow its own GaAsP.<ref name="Schubert"/> In February 1969, Hewlett-Packard introduced the HP Model 5082-7000 Numeric Indicator, the first LED device to use [[integrated circuit]] (integrated [[LED circuit]])  technology.<ref name="Borden"/> It was the first intelligent LED display, and was a revolution in [[digital display]] technology, replacing the [[Nixie tube]] and becoming the basis for later LED displays.<ref>{{cite web |title=Hewlett-Packard 5082-7000 |url=http://www.decadecounter.com/vta/articleview.php?item=1052 |website=The Vintage Technology Association |access-date=15 August 2019}}</ref>\n\nAtalla left HP and joined [[Fairchild Semiconductor]] in 1969.<ref name="Bassett">{{cite book |last1=Bassett |first1=Ross Knox |title=To the Digital Age: Research Labs, Start-up Companies, and the Rise of MOS Technology |date=2007 |publisher=[[Johns Hopkins University Press]] |isbn=9780801886393 |page=328 |url=https://books.google.com/books?id=UUbB3d2UnaAC&pg=PA328}}</ref> He was the vice president and general manager of the Microwave & Optoelectronics division,<ref>{{cite book |title=Annual Report |date=1969 |publisher=[[Fairchild Camera and Instrument Corporation]] |page=6 |url=http://corphist.computerhistory.org/corphist/documents/doc-45621ba5d2e49.pdf}}</ref> from its inception in May 1969 up until November 1971.<ref>{{cite journal |title=Solid State Technology |journal=Solid State Technology |year=1972 |volume=15 |page=79 |url=https://books.google.com/books?id=mCxKAQAAIAAJ |publisher=Cowan Publishing Corporation |quote=Dr. Atalla was general manager of the Microwave & Optoelectronics division from its inception in May 1969 until November 1971 when it was incorporated into the Semiconductor Components Group.}}</ref> He continued his work on LEDs, proposing they could be used for [[Automotive lighting|indicator lights]] and [[optical reader]]s in 1971.<ref>{{cite journal |title=Laser Focus with Fiberoptic Communications |journal=Laser Focus with Fiberoptic Communications |date=1971 |volume=7 |page=28 |url=https://books.google.com/books?id=e8QpAQAAMAAJ |publisher=Advanced Technology Publication |quote=Its chief, John Atalla \u2014 Greene's predecessor at Hewlett-Packard \u2014 sees early applications for LEDs in small displays, principally for indicator lights. Because of their compatibility with integrated circuits, these light emitters can be valuable in fault detection. \u201cReliability has already been demonstrated beyond any doubt,\u201d Atalla continues. \u201cNo special power supplies are required. Design takes no time, you just put the diode in. So introduction becomes strictly an economic question." '''Bright Outlook for Optical Readers''' Atalla is particularly sanguine about applications of diodes in high-volume optical readers.}}</ref> In the 1970s, commercially successful LED devices at less than five cents each were produced by Fairchild Optoelectronics. These devices employed compound [[semiconductor chip]]s fabricated with the [[planar process]] (developed by [[Jean Hoerni]],<ref>{{cite patent | title=Method of Manufacturing Semiconductor Devices |country=US |number=3025589 | inventor=Hoerni, J.A. |fdate=May 1, 1959 |gdate=Mar 20, 1962}}</ref><ref>[http://www.google.com/patents/US3025589 Patent number: 3025589] Retrieved May 17, 2013</ref> based on Atalla's [[surface passivation]] method<ref name="Lojek">{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |url=https://archive.org/details/historysemicondu00loje_697 |url-access=limited |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |pages=[https://archive.org/details/historysemicondu00loje_697/page/n128 120]& 321\u2013323}}</ref><ref name="Bassett46">{{cite book |last1=Bassett |first1=Ross Knox |title=To the Digital Age: Research Labs, Start-up Companies, and the Rise of MOS Technology |date=2007 |publisher=[[Johns Hopkins University Press]] |isbn=9780801886393 |page=46 |url=https://books.google.com/books?id=UUbB3d2UnaAC&pg=PA46}}</ref>). The combination of planar processing for [[chip fabrication]] and innovative [[Chip package|packaging]] methods enabled the team at Fairchild led by optoelectronics pioneer Thomas Brandt to achieve the needed cost reductions.<ref>{{Cite news| author=Bausch, Jeffrey |title =The Long History of Light Emitting Diodes |url=http://www.electronicproducts.com/Optoelectronics/LEDs/The_long_history_of_light-emitting_diodes.aspx|publisher =Hearst Business Communications  |date= December 2011 }}</ref>  LED producers continue to use these methods.<ref>{{Cite journal |last1 = Park |first1 = S. -I. |last2 = Xiong |first2 = Y. |last3 = Kim |first3 = R. -H. |last4 = Elvikis |first4 = P. |last5 = Meitl |first5 = M. |last6 = Kim |first6 = D. -H. |last7 = Wu |first7 = J. |last8 = Yoon |first8 = J. |last9 = Yu |first9 = C. -J. |last10 = Liu |doi = 10.1126/science.1175690 |first10 = Z. |last11 = Huang |first11 = Y. |last12 = Hwang |first12 = K. -C. |last13 = Ferreira |first13 = P. |last14 = Li |first14 = X. |last15 = Choquette |first15 = K. |last16 = Rogers |first16 = J. A. |title = Printed Assemblies of Inorganic Light-Emitting Diodes for Deformable and Semitransparent Displays |journal = Science |volume = 325 |issue = 5943 |pages = 977\u2013981 |year = 2009 |pmid = 19696346 |url = http://vcsel.mntl.illinois.edu/Pubs/Pubs+2009/2009+Sci+325+977+flex+substrate+LED.pdf |url-status = dead |archive-url = https://web.archive.org/web/20151024212822/http://vcsel.mntl.illinois.edu/Pubs/Pubs%202009/2009%20Sci%20325%20977%20flex%20substrate%20LED.pdf |archive-date = October 24, 2015 |df = mdy-all|bibcode= 2009Sci...325..977P |citeseerx = 10.1.1.660.3338|s2cid = 8062948 }}</ref>\n\n[[File:TI-30-LED-Display-3682e1.jpg|thumb|LED display of a [[TI-30]] scientific calculator (ca. 1978), which uses plastic lenses to increase the visible digit size]]\n[[File:8-digit-multiplex-7-segment-LED-X-Ray.tif|thumb|alt=Eight small rectangular blobs, which are the digits, connected by fine hair-like wires to tracks along a circuit board|X-Ray of a 1970s 8-digit LED calculator display]]\nThe early red LEDs were bright enough only for use as indicators, as the light output was not enough to illuminate an area. Readouts in calculators were so small that plastic lenses were built over each digit to make them legible. Later, other colors became widely available and appeared in appliances and equipment.\n\nEarly LEDs were packaged in metal cases similar to those of transistors, with a glass window or lens to let the light out. Modern indicator LEDs are packed in transparent molded plastic cases, tubular or rectangular in shape, and often tinted to match the device color. Infrared devices may be dyed, to block visible light. More complex packages have been adapted for efficient heat dissipation in  [[#High-power|high-power LEDs]]. Surface-mounted LEDs further reduce the package size. LEDs intended for use with [[fiber optics]] cables may be provided with an optical connector.\n\n The first blue-violet LED using magnesium-doped [[gallium nitride]] was made at [[Stanford University]] in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering.<ref>[https://spectrum.ieee.org/tech-talk/geek-life/history/rcas-forgotten-work-on-the-blue-led "Nobel Shocker: RCA Had the First Blue LED in 1972"]. ''IEEE Spectrum''. October 9, 2014</ref><ref>[http://www.oregonlive.com/silicon-forest/index.ssf/2014/10/oregon_tech_ceo_says_nobel_pri.html "Oregon tech CEO says Nobel Prize in Physics overlooks the actual inventors"]. ''The Oregonian''. October 16, 2014</ref> At the time Maruska was on leave from [[RCA|RCA Laboratories]], where he collaborated with Jacques Pankove on related work. In 1971, the year after Maruska left for Stanford, his RCA colleagues Pankove and Ed Miller demonstrated the first blue electroluminescence from zinc-doped gallium nitride, though the subsequent device Pankove and Miller built, the first actual gallium nitride light-emitting diode, emitted green light.<ref>Schubert, E. Fred (2006) ''Light-emitting diodes 2nd ed.'', Cambridge University Press. {{ISBN|0-521-86538-7}} pp. 16\u201317</ref><ref>Maruska, H. (2005). [http://www.sslighting.net/news/features/maruska_blue_led_history.pdf "A Brief History of GaN Blue Light-Emitting Diodes"]. ''LIGHTimes Online \u2013 LED Industry News''. {{webarchive |url=https://web.archive.org/web/20120611224723/http://www.sslighting.net/news/features/maruska_blue_led_history.pdf |date=June 11, 2012 }}</ref> In 1974 the [[U.S. Patent Office]] awarded Maruska, Rhines and Stanford professor David Stevenson a patent for their work in 1972 (U.S. Patent [http://www.google.com/patents/US3819974 US3819974 A]).  Today, magnesium-doping of gallium nitride remains the basis for all commercial blue LEDs and [[laser diode]]s. In the early 1970s, these devices were too dim for practical use, and research into gallium nitride devices slowed.\n\nIn August 1989, [[Cree Inc.|Cree]] introduced the first commercially available blue LED based on the [[Direct and indirect band gaps|indirect bandgap]] semiconductor, silicon carbide (SiC).<ref>[http://www.cree.com/about/milestones.asp Major Business and Product Milestones]. Cree.com. Retrieved on March 16, 2012. {{webarchive |url=https://web.archive.org/web/20110413031614/http://www.cree.com/about/milestones.asp |date=April 13, 2011 }}</ref> SiC LEDs had very low efficiency, no more than about 0.03%, but did emit in the blue portion of the visible light spectrum.<ref>{{Cite journal|last1=Edmond|first1=John A.|last2=Kong|first2=Hua-Shuang|last3=Carter|first3=Calvin H.|date=1993-04-01|title=Blue LEDs, UV photodiodes and high-temperature rectifiers in 6H-SiC|journal=Physica B: Condensed Matter|volume=185|issue=1|pages=453\u2013460|doi=10.1016/0921-4526(93)90277-D|issn=0921-4526|bibcode=1993PhyB..185..453E}}</ref><ref>{{cite web |title=History & Milestones |url=http://www.cree.com/About-Cree/History-and-Milestones |website=Cree.com |publisher=[[Cree Inc.|Cree]] |access-date=2015-09-14 |archive-date=February 16, 2017 |archive-url=https://web.archive.org/web/20170216121011/http://cree.com/About-Cree/History-and-Milestones |url-status=dead }}</ref>\n\nIn the late 1980s, key breakthroughs in GaN [[epitaxial]] growth and [[P-type semiconductor|p-type]] doping<ref>{{cite web|title = GaN-based blue light emitting device development by Akasaki and Amano|website = Takeda Award 2002 Achievement Facts Sheet|publisher = The Takeda Foundation|date = April 5, 2002|url = http://www.takeda-foundation.jp/en/award/takeda/2002/fact/pdf/fact01.pdf|access-date = November 28, 2007}}</ref> ushered in the modern era of GaN-based [[optoelectronic]] devices. Building upon this foundation, [[Theodore Moustakas]] at Boston University patented a method for producing high-brightness blue LEDs using a new two-step process in 1991.<ref>Moustakas, Theodore D. {{US patent|5686738A}} "Highly insulating monocrystalline gallium nitride thin films " Issue date: Mar 18, 1991</ref>\n\nTwo years later, in 1993, high-brightness blue LEDs were demonstrated by [[Shuji Nakamura]] of [[Nichia Corporation]] using a gallium nitride growth process.<ref name="Nakamura">{{cite journal | title=Candela-Class High-Brightness InGaN/AlGaN Double-Heterostructure Blue-Light-Emitting-Diodes | last1=Nakamura | first1=S. | last2=Mukai | first2=T. | last3=Senoh | first3=M. | journal=Appl. Phys. Lett. | year=1994 | volume=64 | page=1687 | bibcode=1994ApPhL..64.1687N | doi=10.1063/1.111832 | issue=13 }}</ref><ref>{{cite web |last1=Nakamura |first1=Shuji |title=Development of the Blue Light-Emitting Diode |url=http://spie.org/x115688.xml |publisher=SPIE Newsroom |access-date=28 September 2015}}</ref><ref>Iwasa, Naruhito; Mukai, Takashi and Nakamura, Shuji {{US patent|5578839}} "Light-emitting gallium nitride-based compound semiconductor device" Issue date: November 26, 1996</ref> In parallel, [[Isamu Akasaki]] and [[Hiroshi Amano]] of [[Nagoya University]] were working on developing the important [[Gallium nitride|GaN]] deposition on sapphire substrates and the demonstration of [[P-type semiconductor|p-type doping]] of GaN. This new development revolutionized LED lighting, making [[Blue laser|high-power blue light sources]] practical, leading to the development of technologies like [[Blu-ray]]{{Citation needed|reason=The article on Blu-ray never mentions blue LEDs and, moreover, claims that laser used is violet and not blue|date=October 2019}}.\n\nNakamura was awarded the 2006 [[Millennium Technology Prize]] for his invention.<ref>[https://www.news.ucsb.edu/2006/012148/2006-millennium-technology-prize 2006 Millennium technology prize awarded to UCSB's Shuji Nakamura]. Ia.ucsb.edu (June 15, 2006). Retrieved on August 3, 2019.</ref>\nNakamura, [[Hiroshi Amano]] and [[Isamu Akasaki]] were awarded the [[Nobel Prize in Physics]] in 2014 for the invention of the blue LED.<ref name="NYT-20141007-DO">{{cite news |last=Overbye |first=Dennis |author-link=Dennis Overbye |title=Nobel Prize in Physics |url=https://www.nytimes.com/2014/10/08/science/isamu-akasaki-hiroshi-amano-and-shuji-nakamura-awarded-the-nobel-prize-in-physics.html |date=7 October 2014 |work=[[The New York Times]] }}</ref> In 2015, a US court ruled that three companies had infringed Moustakas's prior patent, and ordered them to pay licensing fees of not less than US$13 million.<ref>{{cite news |last=Brown |first=Joel |author-link=Joel Brown |title=BU Wins $13 Million in Patent Infringement Suit |url=http://www.bu.edu/today/2015/bu-wins-13-million-in-patent-infringement-suit/ |date=7 December 2015 |work=BU Today |access-date=7 December 2015 }}</ref>\n\nIn 1995, [[Alberto Barbieri]] at the [[Cardiff University]] Laboratory (GB) investigated the efficiency and reliability of high-brightness LEDs and demonstrated a "transparent contact" LED using [[indium tin oxide]] (ITO) on (AlGaInP/GaAs).\n\nIn 2001<ref>{{Cite journal | last1 = Dadgar | first1 = A. | last2 = Alam | first2 = A. | last3 = Riemann | first3 = T. | last4 = Bl\u00e4sing | first4 = J. | last5 = Diez | first5 = A. | last6 = Poschenrieder | first6 = M. | last7 = Strassburg | first7 = M. | last8 = Heuken | first8 = M. | last9 = Christen | first9 = J. | last10 = Krost | first10 = A.| title = Crack-Free InGaN/GaN Light Emitters on Si(111) | doi = 10.1002/1521-396X(200111)188:1<155::AID-PSSA155>3.0.CO;2-P | journal = Physica Status Solidi A | volume = 188 | pages = 155\u2013158 | year = 2001 }}</ref> and 2002,<ref>\n{{Cite journal | last1 = Dadgar | first1 = A. | last2 = Poschenrieder | first2 = M. | last3 = Bl\u00e4Sing | first3 = J. | last4 = Fehse | first4 = K. | last5 = Diez | first5 = A. | last6 = Krost | first6 = A. | doi = 10.1063/1.1479455 | title = Thick, crack-free blue light-emitting diodes on Si(111) using low-temperature AlN interlayers and in situ Si\\sub x]N\\sub y] masking | journal = Applied Physics Letters | volume = 80 | issue = 20 | page = 3670 | year = 2002 |bibcode = 2002ApPhL..80.3670D }}</ref> processes for growing [[gallium nitride]] (GaN) LEDs on [[silicon]] were successfully demonstrated. In January 2012, [[Osram]] demonstrated high-power InGaN LEDs grown on silicon substrates commercially,<ref>{{cite web |url=http://www.osram-os.de/osram_os/EN/Press/Press_Releases/Company_Information/2012/_documents/OSRAM_PI_Production_GaNonSi_e.pdf |title=Success in research: First gallium-nitride LED chips on silicon in pilot stage |access-date=2012-09-15 |url-status=dead |archive-url=https://web.archive.org/web/20120915034646/http://www.osram-os.de/osram_os/EN/Press/Press_Releases/Company_Information/2012/_documents/OSRAM_PI_Production_GaNonSi_e.pdf |archive-date=September 15, 2012 |df=mdy }}. www.osram.de, January 12, 2012.</ref> and GaN-on-silicon LEDs are in production at [[Plessey#Plessey Semiconductors Ltd|Plessey Semiconductors]]. As of 2017, some manufacturers are using SiC as the substrate for LED production, but sapphire is more common, as it has the most similar properties to that of gallium nitride, reducing the need for patterning the sapphire wafer (patterned wafers are known as epi wafers). [[Samsung]], the [[University of Cambridge]], and [[Toshiba]] are performing research into GaN on Si LEDs. Toshiba has stopped research, possibly due to low yields.<ref>Lester, Steve (2014) [https://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/lester_substrate-pkg_tampa2014.pdf Role of Substrate Choice on LED Packaging]. Toshiba America Electronic Components.</ref><ref>[https://www.gan.msm.cam.ac.uk/projects/silicon GaN on Silicon \u2014 Cambridge Centre for Gallium Nitride]. Gan.msm.cam.ac.uk. Retrieved on 2018-07-31.</ref><ref>Bush, Steve. (2016-06-30) [https://www.electronicsweekly.com/blogs/led-luminaries/toshiba-gets-out-of-gan-on-si-leds-2016-06/ Toshiba gets out of GaN-on-Si leds]. Electronicsweekly.com. Retrieved on 2018-07-31.</ref><ref>{{Cite book |doi=10.1109/IEDM.2013.6724622|chapter=LED manufacturing issues concerning gallium nitride-on-silicon (GaN-on-Si) technology and wafer scale up challenges|title=2013 IEEE International Electron Devices Meeting |pages=13.2.1\u201313.2.4 |year=2013 |last1=Nunoue |first1=Shin-ya |last2=Hikosaka |first2=Toshiki |last3=Yoshida |first3=Hisashi |last4=Tajima |first4=Jumpei |last5=Kimura |first5=Shigeya |last6=Sugiyama |first6=Naoharu |last7=Tachibana |first7=Koichi |last8=Shioda |first8=Tomonari |last9=Sato |first9=Taisuke |last10=Muramoto |first10=Eiji |last11=Onomura |first11=Masaaki |isbn=978-1-4799-2306-9|s2cid=23448056}}</ref><ref>Wright, Maury (2 May 2016)  [https://www.ledsmagazine.com/articles/2016/05/samsung-s-tarn-reports-progress-in-csp-and-gan-on-si-leds.html Samsung's Tarn reports progress in CSP and GaN-on-Si LEDs]. LEDs Magazine.</ref><ref>[https://compoundsemiconductor.net/article/99020/Increasing_The_Competitiveness_Of_The_GaN-on-silicon_LED Increasing The Competitiveness Of The GaN-on-silicon LED]. compoundsemiconductor.net (30 March 2016).</ref><ref>[https://www.ledinside.com/news/2015/3/samsung_to_focus_on_silicon_based_led_chip_technology_in_2015 Samsung To Focus on Silicon-based LED Chip Technology in 2015]. LED Inside (17 March 2015).</ref> Some opt towards epitaxy, which is difficult on [[silicon]], while others, like the University of Cambridge, opt towards a multi-layer structure, in order to reduce (crystal) lattice mismatch and different thermal expansion ratios, in order to avoid cracking of the LED chip at high temperatures (e.g. during manufacturing), reduce heat generation and increase luminous efficiency. Sapphire substrate patterning can be carried out with [[nanoimprint lithography]].<ref>Keeping, Steven. (2013-01-15) [https://www.digikey.com/en/articles/techzone/2013/jan/material-and-manufacturing-improvements-enhance-led-efficiency Material and Manufacturing Improvements]. DigiKey. Retrieved on 2018-07-31.</ref><ref>Keeping, Steven. (2014-12-09) [https://www.digikey.com/en/articles/techzone/2014/dec/manufacturers-shift-attention-to-light-quality-to-further-led-market-share-gains Manufacturers Shift Attention to Light Quality to Further LED Market Share Gains]. DigiKey. Retrieved on 2018-07-31.</ref><ref>Keeping, Steven. (2013-09-24) [https://www.digikey.com/en/articles/techzone/2013/sep/will-silicon-substrates-push-led-lighting-into-the-mainstream Will Silicon Substrates Push LED Lighting]. DigiKey. Retrieved on 2018-07-31.</ref><ref>Keeping, Steven. (2015-03-24) [https://www.digikey.com/en/articles/techzone/2015/mar/improved-silicon-substrate-leds-address-high-solid-state-lighting-costs Improved Silicon-Substrate LEDs Address High Solid-State Lighting Costs]. DigiKey. Retrieved on 2018-07-31.</ref><ref>[http://www.toshiba-machine.co.jp/en/NEWS/product/20110518_04.html Development of the Nano-Imprint Equipment ST50S-LED for High-Brightness LED]. Toshiba Machine (2011-05-18). Retrieved on 2018-07-31.</ref><ref>[https://electroiq.com/2015/11/the-use-of-sapphire-in-mobile-device-and-led-industries-part-2/ The use of sapphire in mobile device and LED industries: Part 2 | Solid State Technology]. Electroiq.com (2017-09-26). Retrieved on 2018-07-31.</ref><ref>[http://www.appliedmaterials.com/semiconductor/products/epitaxy Epitaxy]. Applied Materials. Retrieved on 2018-07-31.</ref>\n\nGaN-on-Si is desirable since it takes advantage of existing semiconductor manufacturing infrastructure, however, it is difficult to achieve. It also allows for the wafer-level packaging of LED dies resulting in extremely small LED packages.<ref name="toshiba">https://web.archive.org/web/20140712100725/https://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/lester_substrate-pkg_tampa2014.pdf</ref>\n\nGaN is often deposited using [[Metalorganic vapour-phase epitaxy]] (MOCVD),<ref>Semiengineering: MOCVD vendors eye new apps<!--https://semiengineering.com/mocvd-vendors-eye-new-apps/--></ref> and it also utilizes [[Lift-off (microtechnology)|Lift-off]].\n\n Even though white light can be created using individual red, green and blue LEDs, this results in poor color rendering, since only three narrow bands of wavelengths of light are being emitted. The attainment of high efficiency blue LEDs was quickly followed by the development of the first [[#Phosphor-based LEDs|white LED]]. In this device a {{chem|Y|3|Al|5|O|12}}:Ce (known as "[[YAG]]" or Ce:YAG phosphor) [[cerium]]-doped phosphor coating produces yellow light through [[fluorescence]]. The combination of that yellow with remaining blue light appears white to the eye. Using different [[phosphor]]s produces green and red light through fluorescence. The resulting mixture of red, green and blue is perceived as white light, with improved [[color rendering]] compared to wavelengths from the blue LED/YAG phosphor combination.{{citation needed|date=October 2020}}\n\n[[File:Haitz-law.svg|thumb|upright=1.45|Illustration of [[Haitz's law]], showing improvement in light output per LED over time, with a logarithmic scale on the vertical axis]]\n\nThe first white LEDs were expensive and inefficient. However, the light output of LEDs has increased [[exponential growth|exponentially]]. The latest research and development has been propagated by Japanese manufacturers such as [[Panasonic]], and [[Nichia]], and by Korean and Chinese manufacturers such as [[Samsung]], Solstice, Kingsun, Hoyol and others. This trend in increased output has been called [[Haitz's law]] after Roland Haitz.<ref>{{Cite journal|doi=10.1038/nphoton.2006.78|title=Haitz's law|year=2007|journal=[[Nature Photonics]]|volume=1|page=23|issue=1|bibcode = 2007NaPho...1...23. |doi-access=free}}</ref><ref>{{Cite web | url=http://www.ledcornbulbs.com/LEDlightsapplication/List-of-Top-10-LED-light-manufacturer-in-China-19.html |title = List of Top 10 LED light manufacturer in China|archive-url = https://web.archive.org/web/20141009180039/http://www.ledcornbulbs.com/LEDlightsapplication/List-of-Top-10-LED-light-manufacturer-in-China-19.html|archive-date = 9 October 2014}}</ref>\n\nLight output and efficiency of blue and near-ultraviolet LEDs rose and the cost of reliable devices fell. This led to relatively high-power white-light LEDs for illumination, which are replacing incandescent and fluorescent lighting.<ref>{{cite web | url=http://www.electrooptics.com/features/junjul06/junjul06leds.html | title=LED there be light, Nick Morris predicts a bright future for LEDs | website=Electrooptics.com | date=1 June 2006 | first=Nick| last=Morris }}</ref><ref>{{Cite journal|url=https://www.forbes.com/2008/02/27/incandescent-led-cfl-pf-guru_in_mm_0227energy_inl.html|title=The LED Illumination Revolution|journal=[[Forbes]]|date=February 27, 2008}}</ref>\n\nExperimental white LEDs were demonstrated in 2014 to produce 303 lumens per watt of electricity (lm/W); some can last up to 100,000 hours.<ref>[https://www.nobelprize.org/nobel_prizes/physics/laureates/2014/press.html Press Release], Official Nobel Prize website, 7 October 2014</ref><ref>[http://www.cree.com/news-media/news/article/cree-first-to-break-300-lumens-per-watt-barrier Cree First to Break 300 Lumens-Per-Watt Barrier] {{Webarchive|url=https://web.archive.org/web/20180728221801/http://www.cree.com/news-media/news/article/cree-first-to-break-300-lumens-per-watt-barrier |date=July 28, 2018 }}. Cree.com (2014-03-26). Retrieved on 2018-07-31.</ref> However, commercially available LEDs have an efficiency of up to 223 lm/W as of 2018.<ref>[https://www.samsung.com/led/lighting/mid-power-leds/3030-leds/lm301b/ LM301B | SAMSUNG LED | Samsung LED Global Website]. Samsung.com. Retrieved on 2018-07-31.</ref><ref>[https://www.samsung.com/led/about-us/news-events/news/news-detail-37/ Samsung Achieves 220 Lumens per Watt with New Mid-Power LED Package]. Samsung.com (2017-06-16). Retrieved on 2018-07-31.</ref><ref>[http://luxreview.com/article/2018/01/led-breakthrough-promises-ultra-efficient-luminaires LED breakthrough promises ultra efficient luminaires | Lux Magazine] {{Webarchive|url=https://web.archive.org/web/20190803155806/https://luxreview.com/article/2018/01/led-breakthrough-promises-ultra-efficient-luminaires |date=August 3, 2019 }}. Luxreview.com (2018-01-19). Retrieved on 2018-07-31.</ref> A previous record of 135 lm/W was achieved by Nichia in 2010.<ref>{{Cite web|url=https://phys.org/news/2010-08-white-super-high-luminous-efficacy.html|title=White LEDs with super-high luminous efficacy could satisfy all general lighting needs|website=phys.org}}</ref> Compared to incandescent bulbs, this is a huge increase in electrical efficiency, and even though LEDs are more expensive to purchase, overall lifetime cost is significantly cheaper than that of incandescent bulbs.<ref>[https://www.eia.gov/todayinenergy/detail.cfm?id=15471 LED bulb efficiency expected to continue improving as cost declines]. U.S. Energy Information Administration (March 19, 2014)</ref>\n\nThe LED chip is encapsulated inside a small, plastic, white mold. It can be encapsulated using resin ([[polyurethane]]-based), silicone, or epoxy containing (powdered) Cerium-doped YAG phosphor. After allowing the solvents to evaporate, the LEDs are often tested, and placed on tapes for [[SMT placement equipment]] for use in LED light bulb production. Encapsulation is performed after probing, dicing, die transfer from wafer to package, and wire bonding or flip chip mounting, perhaps using [[Indium tin oxide]], a transparent electrical conductor. In this case, the bond wire(s) are attached to the ITO film that has been deposited in the LEDs.\nSome "remote phosphor" LED light bulbs use a single plastic cover with YAG phosphor for several blue LEDs, instead of using phosphor coatings on single-chip white LEDs.<ref>http://www.lamptech.co.uk/Spec%20Sheets/LEDi%20Philips%20806K58RP827-B22d%20Prince.htm</ref>\n\nThe temperature of the phosphor during operation and how it is applied limits the size of an LED die. [[Wafer-level packaging|Wafer-level packaged]] white LEDs allow for extremely small LEDs.<ref name="toshiba"/>"}},
{"article_title": "Legacy system", "pageid": "18295", "revid": "1060352220", "timestamp": "2021-12-15T00:25:43Z", "history_paths": [["Legacy system --- Introduction ---", "Overview"]], "categories": ["legacy systems", "legacy hardware", "technological change"], "heading_tree": {"Legacy system --- Introduction ---": {"Overview": {}, "Problems posed by legacy computing": {}, "Improvements on legacy software systems": {}, "NASA example": {}, "Perspectives on legacy code": {}, "Additional uses of the term ''Legacy'' in computing": {}, "Brownfield architecture": {}, "Alternative view": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Legacy system --- Introduction ---|Overview": "[[File:Windows XP sighted 'in the wild' on a cash point, 3 August 2018.jpg|thumb|right|Although off-support since April 2014, [[Windows XP]] has endured continued use in fields such as [[automated teller machine|ATM]] [[operating system]] software.]]\n\nThe first use of the term ''legacy'' to describe computer systems probably occurred in the 1970s.{{citation needed|date=January 2019}}  By the 1980s it was commonly used to refer to existing computer systems to distinguish them from the design and implementation of new systems. Legacy was often heard during a conversion process, for example, when moving data from the legacy system to a new database.\n\nWhile this term may indicate that some engineers may feel that a system is out of date, a legacy system can continue to be used for a variety of reasons. It may simply be that the system still provides for the users' needs. In addition, the decision to keep an old system may be influenced by economic reasons such as [[return on investment]] challenges or [[vendor lock-in]], the inherent challenges of [[change management]], or a variety of other reasons other than functionality. [[Backward compatibility]] (such as the ability of newer systems to handle legacy [[file format]]s and [[character encoding]]s) is a goal that [[software developer]]s often include in their work.\n\nEven if it is no longer used, a legacy system may continue to impact the organization due to its historical role. Historic data may not have been converted into the new system format and may exist within the new system with the use of a customized [[schema crosswalk]], or may exist only in a [[data warehouse]]. In either case, the effect on [[business intelligence]] and [[operational reporting]] can be significant.  A legacy system may include procedures or terminology which are no longer relevant in the current context, and may hinder or confuse understanding of the methods or technologies used.\n\nOrganizations can have compelling reasons for keeping a legacy system, such as:\n* The system works satisfactorily, and the owner sees no reason to change it.\n* The costs of redesigning or replacing the system are prohibitive because it is large, [[monolithic system|monolithic]], and/or complex.\n* Retraining on a new system would be costly in lost time and money, compared to the anticipated appreciable benefits of replacing it (which may be zero).\n* The system requires near-constant [[availability]], so it cannot be taken out of service, and the cost of designing a new system with a similar availability level is high. Examples include systems to handle customers' accounts in [[bank]]s, [[computer reservations system]]s, [[air traffic control]], energy distribution ([[power grid]]s), [[nuclear power plant]]s, military defense installations, and systems such as the [[TOPS]] database.\n* The way that the system works is not well understood. Such a situation can occur when the designers of the system have left the organization, and the system has either not been fully documented or documentation has been lost.\n* The user expects that the system can easily be replaced when this becomes necessary.\n* Newer systems perform undesirable (especially for individual or non-institutional users) secondary functions such as ''a'') tracking and reporting of user activity and/or ''b'') automatic updating that creates "[[Backdoor (computing)|back-door]]" security vulnerabilities and leaves end users dependent on the good faith and honesty of the vendor providing the updates.  This problem is especially acute when these secondary functions of a newer system cannot be disabled."}},
{"article_title": "Lightworks", "pageid": "18495", "revid": "1059839111", "timestamp": "2021-12-11T23:28:07Z", "history_paths": [["Lightworks --- Introduction ---", "History"]], "categories": ["film and video technology", "video editing software", "1989 software", "video editing software for linux"], "heading_tree": {"Lightworks --- Introduction ---": {"Features": {}, "Use in films and TV series": {}, "History": {"Gee Broadcast ownership, 2004\u20132009": {}, "EditShare ownership, 2009\u20132020": {"Windows version released at NAB 2012": {}, "Windows version 11.1 released 29 May 2013": {}, "Linux version announced at IBC 2012": {}, "Lightworks 12 beta released for Windows, Linux and Mac": {}, "Lightworks 12.6 released for Windows, Linux and Mac": {}, "Lightworks 12.7 released for Windows, Linux and Mac": {}, "Lightworks 14.5 released for Windows, Linux and Mac": {}}, "LWKS Software Ltd ownership, 2020-present": {}}, "Users": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Lightworks --- Introduction ---|History": "OLE Limited was founded in 1989 by Paul Bamborough, Nick Pollock and Neil Harris. In 1994 it was sold to [[Tektronix]],<ref>{{cite web|url=https://nytimes.com/1995/04/11/business/company-news-tektronix-to-buy-lightworks-editing-systems.html |title=Company News; Tektronix To Buy Lightworks Editing Systems - New York Times |work=Nytimes.com |date=1995-04-11 |access-date=2011-09-08}}</ref> who were not successful at developing the company's products. In 1999 it was sold on to the newly formed Lightworks Inc., then owned by [[Fairlight Japan]], and then purchased by [[Gee Broadcast]] in May 2004.<ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/Press_Releases/First%20major%20order%20for%20Lightworks%20under%20new%20ownership.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2012-05-04|archive-url=https://web.archive.org/web/20190517052020/https://www.interlab-net.com/docs/lightworks/Press_Releases/First%20major%20order%20for%20Lightworks%20under%20new%20ownership.pdf|archive-date=2019-05-17|url-status=dead}}</ref><ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/Press_Releases/LWKS_PR_version2.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2012-05-04|archive-url=https://web.archive.org/web/20190517055206/https://www.interlab-net.com/docs/lightworks/Press_Releases/LWKS_PR_version2.pdf|archive-date=2019-05-17|url-status=dead}}</ref>\n\n \nUnder Gee Broadcast ownership, new product releases resumed with the release of the Lightworks ''Touch'' range,<ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/Press_Releases/PR-1_Product_launch@IBC.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2012-05-04|archive-url=https://web.archive.org/web/20190517052101/https://www.interlab-net.com/docs/lightworks/Press_Releases/PR-1_Product_launch@IBC.pdf|archive-date=2019-05-17|url-status=dead}}</ref><ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/Press_Releases/PR-3_editors_feel_back.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2012-05-04|archive-url=https://web.archive.org/web/20190517051322/https://www.interlab-net.com/docs/lightworks/Press_Releases/PR-3_editors_feel_back.pdf|archive-date=2019-05-17|url-status=dead}}</ref> and the ''Alacrity''<ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/Lightworks_Alacrity_MR.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2012-05-04|archive-url=https://web.archive.org/web/20190517062338/https://www.interlab-net.com/docs/lightworks/Lightworks_Alacrity_MR.pdf|archive-date=2019-05-17|url-status=dead}}</ref> and ''Softworks''<ref>{{cite web|url=http://www.interlab-net.com/docs/lightworks/lw_user%20doc/Softworks&Alacrity_Manual_rev_4.pdf|title=Docs and software downloads|first=Alexandre Stein|last=Interlab|access-date=2020-02-27|archive-url=https://web.archive.org/web/20190517055715/https://www.interlab-net.com/docs/lightworks/lw_user%20doc/Softworks%26Alacrity_Manual_rev_4.pdf|archive-date=2019-05-17|url-status=dead}}</ref> ranges for SD & HD editing.<ref>{{cite web |url=http://broadcastengineering.com/products/lightworks-softworks-new-version/ |title=Lightworks ships Softworks Version 1.1 |publisher=broadcastengineering.com |date=2006-10-27 |access-date=2012-05-06 |url-status=dead |archive-url=https://web.archive.org/web/20080609023206/http://broadcastengineering.com/products/lightworks-softworks-new-version/ |archive-date=2008-06-09}}</ref> Softworks offered the Lightworks User Interface and toolset in a software only package for laptops or office workstations. Softworks and Alacrity supported mixed formats and resolutions in real time and project output in different resolutions without re-[[Rendering (computer graphics)|rendering]]. Alacrity supported dual outputs while the same facility was available for Softworks users as an option.<ref>{{cite web |url=http://www.interlab-net.com/docs/lightworks/lw_user%20doc/Softworks&Alacrity_Manual_rev_4.pdf |title=Lightworks Softworks User Manual v4 |access-date=2012-05-06 |archive-url=https://web.archive.org/web/20190517055715/https://www.interlab-net.com/docs/lightworks/lw_user%20doc/Softworks%26Alacrity_Manual_rev_4.pdf |archive-date=2019-05-17 |url-status=dead }}</ref>\n\n \nIn August 2009 the UK and US based company ''[[EditShare]]'' acquired Gee Broadcast and the Lightworks editing platform from, along with their video server system ''GeeVS''.<ref>{{cite web|url=http://www.editshare.com/index.php?option=com_content&view=article&id=126:editshare-acquires-geevs-and-lightworks-technology&catid=43:press-releases&Itemid=184|title=EditShare Ships New Version of Flow Media Asset Management Solution - Press - News & Events|last=EditShare}}</ref>\n\nAt the annual convention of the [[National Association of Broadcasters]], [[NAB Show]], on 11 April 2010, EditShare announced that they plan to transform Lightworks into Lightworks Open Source.<ref>{{cite web|url=http://www.editshare.com/index.php?option=com_content&task=view&id=164&Itemid=146|title=Welcome to EditShare|last=EditShare}}</ref> It was presented at [[International Broadcasting Convention|IBC]] in Amsterdam September 2010.<ref>{{cite web|url=http://editshare.com/?option=com_content&task=view&id=173&Itemid=54|title=EditShare|last=EditShare}}</ref>\n\nOn 9 November 2010, EditShare announced that Lightworks would be downloadable on 29 November of the same year, at first exclusively for the users who had registered during the initial announcement,<ref>[http://www.editshare.com/email/lightworks-nov10-online.html Lightworks News Nov 2010] {{webarchive|url=https://web.archive.org/web/20101112013052/http://www.editshare.com/email/lightworks-nov10-online.html |date=2010-11-12 }}</ref> but subsequently publishing the software as "public beta".<ref name="Lightworks">{{cite web|url=http://www.lightworksbeta.com/ |title=Lightworks |publisher=Lightworksbeta.com |access-date=2011-09-08}}</ref>\n\nEditShare planned the release of the open source version in Q4 of 2011, after they finished [[code review]].<ref name="Lightworks"/> They plan to make money from proprietary plugins offered in their associated online shop, including plugins needed to access professional video formats. Shortly before the scheduled release date of 29 November 2011, EditShare announced that an open source release of the software would be temporarily delayed, but did not announce a new release date. The announcement noted that they were not yet satisfied with the stability of the new version.<ref>{{cite web|url=http://www.golem.de/1111/87980.html|title=Lightworks: Freie Videoschnittsoftware wird etwas sp\u00e4ter aktualisiert - Golem.de}}</ref><ref>{{Cite web |url=http://www.lightworksbeta.com/index.php?option=com_content&view=article&id=122&Itemid=263 |title=Archived copy |access-date=2011-12-08 |archive-url=https://web.archive.org/web/20120525031007/http://www.lightworksbeta.com/index.php?option=com_content&view=article&id=122&Itemid=263 |archive-date=2012-05-25 |url-status=dead }}</ref>\n\n \nAfter an 18-month beta program, EditShare released Lightworks 11, for Windows only, on 28 May 2012. The non beta release of Lightworks includes a host of new features for editors, and runs on wide range of PC hardware. The software was re-designed and re-written for portability (versions for Linux and Mac OS X have also been released) and now supports many more codecs including AVCHD, H.264, AVC-Intra, DNxHD, ProRes, Red R3D, DPX, XDCAM HD 50, XDCAM EX, DVD, Blu-ray, and 4K, but only for the paid Pro version. The free version supports DV, MPEG, Uncompressed and other codecs for both import and export.<ref>{{cite web|url=http://www.lwks.com/index.php?option=com_content&view=article&id=57&Itemid=182 |title=Lightworks: Top Features |publisher=lwks.com |date=2012-05-28 |access-date=2012-05-29}}</ref><ref>{{cite web|url=http://www.lwks.com/index.php?option=com_content&view=article&id=24&Itemid=179 |title=Lightworks: All Features |publisher=lwks.com |date=2012-05-28 |access-date=2012-05-29}}</ref><ref>{{cite web|url=http://www.lwks.com/index.php?option=com_content&view=article&id=13&Itemid=174 |title=Lightworks: Tech Specs and Compatibility |publisher=lwks.com |date=2012-05-28 |access-date=2012-05-29}}</ref>\n\n \nOn 29 May 2013, v11.1 stable release was made available for download. A major development in the Pro version is much improved performance of the H.264/AVC codec in MP4 and MOV containers. This makes it possible to edit this format natively, even with less powerful CPUs. This should interest HDSLR and GoPro camera users. Native editing of H.264 MTS files has been possible since version 11.0.3.\n\nThis version of Lightworks has also replaced [[Aladdin Knowledge Systems#DRM|HASP]] with the new [[EditShare Licensing System]] (ELS), which eliminates some installation problems. Lightworks Free users can now download the 64 bit version, which was previously limited to Pro users. The Free version now also comes with a 30-day Pro Trial period.<ref>{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=47457&Itemid=81 |title=New EditShare Licensing System (ELS) |publisher=lwks.com |date=2013-06-28 |access-date=2013-06-04}}</ref>\n\n EditShare demonstrated the Linux version at the [[NAB Show|NAB]] in Las Vegas in April 2012, and posted a video of it running on Ubuntu on their YouTube channel.<ref>{{cite web|url=https://www.youtube.com/watch?v=ek5BvjHuHPg&hd=1| archive-url=https://web.archive.org/web/20120518154428/http://www.youtube.com/watch?v=ek5BvjHuHPg&gl=US&hl=en| archive-date=2012-05-18 | url-status=dead|title=Screen capture of Lightworks on Ubuntu Linux|last=EditShare|date=25 April 2012|via=YouTube}}</ref> At [[International Broadcasting Convention|IBC]] in Amsterdam in September, an updated Linux demo was presented, and EditShare announced that the initial Linux alpha version would become available on 30 October .<ref>{{cite web|url=http://editshare.posterous.com/at-last-lightworks-for-linux-will-be-availabl|title=Good night, Posterous}}</ref> Lightworks 11 alpha for Linux was released on 30 April 2012, but only to a limited audience.<ref name=linux-alpha>{{cite web|last=Sneddon|first=Joey-Elijah|title=LightWorks for Linux Opens Alpha Access For Limited Time|url=http://www.omgubuntu.co.uk/2013/01/lightworks-for-linux-opens-alpha-access-for-limited-time|work=OMG! Ubuntu!|publisher=Ohso Ltd|access-date=19 March 2013|date=10 January 2013}}</ref> The Linux version of Lightworks was made available as a Public Beta on 30 April 2013.<ref name="11.1">{{cite web |title=It's Here - Preview Lightworks for Mac at NAB 2013|url=http://prmac.com/release-id-56324.htm |work=EditShare |access-date=8 April 2013 |date=8 April 2013}}</ref><ref>{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=36286&Itemid=81|title=Forum}}</ref><ref name="linux beta">{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=44717&Itemid=81|title=Lightworks LinuxPublic Beta Is Now Available To Download|access-date=2013-05-01}}</ref>\n\n On 8 August 2014, the first beta of Lightworks version 12 working on Windows, Linux and Mac was released.<ref>{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=76403&Itemid=81|title=Lightworks Release 11.5.2 Now Available To Download}}</ref>\n\n On 29 August 2015, Lightworks version 12.5 for Windows, Linux and Mac was released.<ref>{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=101112&Itemid=81|title=Lightworks Version 12.5 Now Available on Windows Linux and Mac OS X!}}</ref>\n\n On 4 February 2016, Lightworks version 12.6 for Windows, Linux and Mac was released.<ref>{{cite web|url=http://www.lwks.com/index.php?option=com_kunena&func=view&catid=19&id=107714&Itemid=81|title=Lightworks Version 12.6.0 Now Available on Windows Linux and Mac OS X!}}</ref>\n\n In October 2018, Lightworks released version 14.5 for Windows, Linux and Mac platforms. 14.5 added a vast array of new features including variable frame rate support, a huge amount of codec support including Red Cinema R3D, Cineform and Blackmagic Q1 codecs.{{citation needed|date=January 2019}}\n\n \nIn September 2020, a new company, LWKS Software Ltd, founded in August of the same year<ref>{{Cite web|title=LWKS SOFTWARE LTD - Overview (free company information from Companies House)|url=https://beta.companieshouse.gov.uk/company/12792578|access-date=2020-09-21|website=beta.companieshouse.gov.uk|language=en}}</ref> by two members of the development team, took ownership of Lightworks, as well as QScan AQC software. the agreement also mentions Key member of the development teams of both software joining the new company.<ref>{{Cite web|title=Lightworks Editing System Relaunched with New Company {{!}} Hollywood Reporter|url=https://www.hollywoodreporter.com/behind-screen/lightworks-editing-system-relaunched-with-new-company|access-date=2020-09-21|website=www.hollywoodreporter.com|date=15 September 2020}}</ref>"}},
{"article_title": "Minix", "pageid": "18977", "revid": "1060634891", "timestamp": "2021-12-16T18:50:02Z", "history_paths": [["Minix --- Introduction ---", "Implementation"]], "categories": ["minix", "1987 software", "arm operating systems", "computer science in the netherlands", "dutch inventions", "educational operating systems", "free software operating systems", "information technology in the netherlands", "lightweight unix-like systems", "microkernel-based operating systems", "microkernels", "operating system distributions bootable from read-only media", "software using the bsd license", "unix variants"], "heading_tree": {"Minix --- Introduction ---": {"Implementation": {"Minix 1.0": {}, "Minix 1.5": {}, "Minix 2.0": {"Minix-vmd": {}}, "Minix 3": {}}, "Relationship with Linux": {"Early influence": {}, "''Samizdat'' claims": {}}, "Licensing": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Minix --- Introduction ---|Implementation": "[[Andrew S. Tanenbaum]] created MINIX at [[Vrije Universiteit]] in [[Amsterdam]] to exemplify the principles conveyed in his [[textbook]], ''[[Operating Systems: Design and Implementation]]'' (1987).\n\nAn abridged 12,000 lines of the [[C (programming language)|C]] [[source code]] of the [[kernel (operating system)|kernel]], [[memory management|memory manager]], and [[file system]] of MINIX 1.0 are printed in the book. [[Prentice-Hall]] also released MINIX source code and binaries on [[floppy disk]] with a reference manual. MINIX 1 was system-call compatible with [[Seventh Edition Unix]].<ref>{{cite book |url=https://archive.org/details/operatingsystems00tane |title=Operating Systems Design and Implementation |isbn=0-13-638677-6 |year=1997 |access-date=August 2, 2011 |first1=Andrew S. |last1=Tanenbaum |author-link1=Andrew S. Tanenbaum |first2=Albert S. |last2=Woodhull |edition=Second |orig-year=1986 |oclc=35792209 |url-access=registration }}</ref>\n\nTanenbaum originally developed MINIX for compatibility with the [[IBM PC]] and [[IBM PC/AT]] [[8088]] [[microcomputer]]s available at the time.\n\n MINIX 1.5, released in 1991, included support for [[MicroChannel]] [[IBM PS/2]] systems and was also [[Porting|ported]] to the [[Motorola 68000]] and [[SPARC]] architectures, supporting the [[Atari ST]], [[Commodore Amiga]], [[Apple Macintosh]]<ref>{{cite web|url=https://github.com/macminix|title=MacMinix}}</ref> and [[Sun Microsystems|Sun]] [[SPARCstation]] [[Platform (computing)|computer platforms]].  There were also unofficial ports to [[Intel 386]] [[PC compatible]]s (in [[32-bit]] [[protected mode]]), [[National Semiconductor]] [[NS320xx|NS32532]], [[ARM architecture|ARM]] and [[Inmos]] [[transputer]] processors. [[Meiko Scientific]] used an early version of MINIX as the basis for the [[MeikOS]] operating system for its transputer-based [[Computing Surface]] [[parallel computer]]s. A version of MINIX running as a user process under [[SunOS]] and [[Solaris (operating system)|Solaris]] was also available, a simulator named SMX (operating system) or just '''SMX''' for short.<ref>{{cite web|url=http://www.minix3.org/previous-versions/CD-ROM-2.0/README.TXT|title=Welcome to MINIX|format=TXT|date=July 22, 2005|access-date=August 2, 2011|first1=Andrew S. |last1=Tanenbaum |author-link1=Andrew S. Tanenbaum |first2=Albert S. |last2=Woodhull |first3=Kees |last3=Bot}}</ref><ref>{{cite web |url=http://www.csd.uoc.gr/~hy345/assignments/99b/smx_howto.html |title=Installing and running MINIX for Solaris (SMX) |access-date=August 2, 2011 |first=M. |last=Flouris}}</ref>\n\n [[File:MINIX 2.0.4 Startup Login.png|thumb|MINIX 2.0.4 system startup and login prompt]]\n[[File:MINIX 2.0.4 Shell Interaction.png|thumb|MINIX 2.0.4 [[Unix shell|shell]] interaction]]\n\nDemand for the 68k-based architectures waned, however, and MINIX 2.0, released in 1997, was only available for the [[x86]] and [[Solaris (operating system)|Solaris]]-hosted SPARC architectures.  It was the subject of the second edition of Tanenbaum's textbook, cowritten with Albert Woodhull and was distributed on a [[CD-ROM]] included with the book. MINIX 2.0 added [[POSIX]].1 compliance, support for 386 and later processors in 32-bit mode and replaced the [[Amoeba (operating system)|Amoeba]] network protocols included in MINIX 1.5 with a [[TCP/IP]] stack.\n\nVersion 2.0.3 was released in May 2001. It was the first version after MINIX had been relicensed under the [[BSD licenses|BSD-3-Clause]] license, which was retroactively applied to all previous versions.<ref name="bsd3clause">{{cite web|title=BSD-3-Clause|url=http://www.cs.vu.nl/pub/minix/LICENSE|access-date=2021-06-14|archive-date=2000-04-14|archive-url=https://web.archive.org/web/20000414094106/http://www.cs.vu.nl/pub/minix/LICENSE|url-status=dead}}</ref>\n\n {{main|Minix-vmd}}\n\n[[Minix-vmd]] is a variant of MINIX 2.0 for Intel [[IA-32]]-compatible processors, created by two Vrije Universiteit researchers, which adds [[virtual memory]] and support for the [[X Window System]].\n\n {{Main|MINIX 3}}\n[[File:MINIX 3.2 Top Command.png|thumb|Minix 3.2 running the "[[top (software)|top]]" system monitoring command]]\n[[File:Minix 3.png|thumb|Minix 3 running [[X Window System|X11]] with the [[twm]] window manager]]\n\nMinix 3 was publicly announced on 24 October 2005 by Tanenbaum during his keynote speech at the [[Association for Computing Machinery]] (ACM) Symposium on Operating Systems Principles (SOSP). Although it still serves as an example for the new edition of Tanenbaum's textbook -coauthored by Albert S. Woodhull-, it is comprehensively redesigned to be "usable as a serious system on resource-limited and embedded computers and for applications requiring high reliability."<ref>{{cite journal |last1=Herder |first1=J. N. |last2=Bos |first2=H. |last3=Gras |first3=B. |last4=Homburg |first4=P. |last5=Tanenbaum |first5=A. S. |title=Minix 3 |doi=10.1145/1151374.1151391 |journal=ACM SIGOPS Operating Systems Review |volume=40 |issue=3 |pages=80 |year=2006 |s2cid=30216714 }}</ref>\n\nMinix 3 currently supports [[IA-32]] and [[ARM architecture]] systems. It is available in a [[Live CD]] format that allows it to be used on a computer without installing it on the hard drive, and in versions compatible with hardware emulating and virtualizing systems, including [[Bochs]], [[QEMU]], [[VMware Workstation]]/[[VMware Fusion|Fusion]], [[VirtualBox]], and [[Microsoft Virtual PC]].\n\nVersion 3.1.2 was released on 18 April 2006. It was the first version after MINIX had been relicensed under the [[BSD licenses|BSD-3-Clause]] license with a new fourth clause.<ref name="3.1.2 license">{{cite web|title=LICENSE |url=https://github.com/Stichting-MINIX-Research-Foundation/minix/blob/v3.1.2/LICENSE|access-date=2021-06-15|archive-date=2021-06-15|archive-url=https://web.archive.org/web/20210615005833/https://github.com/Stichting-MINIX-Research-Foundation/minix/blob/v3.1.2/LICENSE|url-status=live}}</ref>\n\nVersion 3.1.5 was released on 5 November 2009. It contains [[X11]], [[emacs]], [[vi]], [[C compiler|cc]], [[GNU Compiler Collection|gcc]], [[perl]], [[Python (programming language)|python]], [[Almquist shell|ash]], [[Bash (Unix shell)|bash]], [[zsh]], [[ftp]], [[Secure Shell|ssh]], [[telnet]], [[Pine (e-mail client)|pine]], and over 400 other common [[Unix]] utility programs. With the addition of X11, this version marks the transition away from a text-only system. In many cases it can automatically restart a crashed driver without affecting running processes. In this way, MINIX is self-healing and can be used in applications demanding high reliability. MINIX 3 also has support for [[virtual memory]] management, making it suitable for desktop OS use.<ref>{{cite web|url=http://groups.google.com/group/minix3/msg/86c914a0c13376fe|title=New to minix|date=November 10, 2010|access-date=August 2, 2011|first=Ulrich|last=Schmidt}}</ref> Desktop applications such as [[Firefox]] and [[OpenOffice.org]] are not yet available for MINIX 3 however.\n\nAs of version 3.2.0, the [[User space|userland]] was mostly replaced by that of [[NetBSD]] and support from [[pkgsrc]] became possible, increasing the available software applications that MINIX can use. [[Clang]] replaced the prior compiler (with [[GNU Compiler Collection|GCC]] now having to be manually compiled), and [[GDB]], the GNU debugger, was ported.<ref name=wiki-releases>{{cite web|title=MINIX Releases|url=http://wiki.minix3.org/en/MinixReleases|work=wiki.minix3.org|access-date=29 February 2012|url-status=dead|archive-url=https://web.archive.org/web/20120531025416/http://wiki.minix3.org/en/MinixReleases|archive-date=31 May 2012}}</ref><ref>[https://lwn.net/Articles/485658/ MINIX 3.2: A microkernel with NetBSD applications [LWN.net]]</ref>\n\nMinix 3.3.0, released in September 2014, brought ARM support.\n\nMinix 3.4.0RC, Release Candidates became available in January 2016;<ref>{{Cite web|url=http://download.minix3.org/iso/snapshot/|title=Index of /iso/snapshot/|website=download.minix3.org|access-date=2016-10-14}}</ref> however, a stable release of MINIX 3.4.0 is yet to be announced.\n\nMinix supports many programming languages, including [[C (programming language)|C]], [[C++]], [[FORTRAN]], [[Modula-2]], [[Pascal (programming language)|Pascal]], [[Perl]], [[Python (programming language)|Python]], and [[Tcl]].\n\nMinix 3 still has an active development community with over 50 people attending MINIXCon 2016, a conference to discuss the history and future of MINIX.<ref>{{Cite web|url=http://www.minix3.org/conference/2016/program.html|title=MINIXCon 2016|website=www.minix3.org|access-date=2016-10-14}}</ref>\n\nAll Intel chipsets post-2015 are running MINIX 3 internally as the software component of the [[Intel Management Engine]].<ref>{{Cite web|url=http://blog.ptsecurity.com/2017/08/disabling-intel-me.html|title=Positive Technologies research|website=blog.ptsecurity.com|access-date=2017-09-06}}</ref><ref>[https://www.zdnet.com/article/minix-intels-hidden-in-chip-operating-system/ Minix: Intel's hidden in-chip operating system]</ref>"}},
{"article_title": "Microscopy", "pageid": "19567", "revid": "1054368957", "timestamp": "2021-11-09T16:58:37Z", "history_paths": [["Microscopy --- Introduction ---", "History"]], "categories": ["microscopy", "microbiology techniques", "laboratory techniques", "antonie van leeuwenhoek", "science and technology in the dutch republic", "dutch inventions", "17th century in science"], "heading_tree": {"Microscopy --- Introduction ---": {"History": {}, "Optical microscopy": {"Limitations": {}, "Techniques": {"Bright field": {}, "Oblique illumination": {}, "Dark field": {}, "Dispersion staining": {}, "Phase contrast": {}, "Differential interference contrast": {}, "Interference reflection": {}, "Fluorescence": {}, "Confocal": {}, "Two-photon microscopy": {}, "Single plane illumination microscopy and light sheet fluorescence microscopy": {}, "Wide-field multiphoton microscopy": {}, "Deconvolution": {}}, "Sub-diffraction techniques": {}, "Serial time-encoded amplified microscopy": {}, "Extensions": {}, "Other enhancements": {}, "X-ray": {}}, "Electron microscopy": {}, "Scanning probe microscopy": {"Ultrasonic force": {}}, "Ultraviolet microscopy": {}, "Infrared microscopy": {}, "Digital holographic microscopy": {}, "Digital pathology (virtual microscopy)": {}, "Laser microscopy": {}, "Photoacoustic microscopy": {}, "Amateur microscopy": {}, "Application in forensic science": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microscopy --- Introduction ---|History": "[[File:Anthonie van Leeuwenhoek (1632-1723). Natuurkundige te Delft Rijksmuseum SK-A-957.jpeg|thumb|250px|Often considered to be the first acknowledged [[list of microscopists|microscopist]] and [[microbiologist]], [[Antonie van Leeuwenhoek]] is best known for his pioneering work in the field of microscopy and for his contributions toward the establishment of [[microbiology]] as a scientific discipline.<ref name="BrianJFord_1992">{{cite journal |author=Ford, Brian J. |date=1992 |title=From Dilettante to Diligent Experimenter: a Reappraisal of Leeuwenhoek as microscopist and investigator |journal=Biology History |volume= 5 |issue=3 |url= http://www.brianjford.com/a-avl01.htm|author-link=Brian J. Ford }}</ref>]]\n\nThe field of microscopy ([[optical microscopy]]) dates back to at least the 17th-century. Earlier microscopes, single [[lens (optics)|lens]] [[magnifying glass]]es with limited magnification, date at least as far back as the wide spread use of lenses in [[eyeglasses]] in the 13th century<ref>Atti Della Fondazione Giorgio Ronchi E Contributi Dell'Istituto Nazionale Di Ottica, Volume 30, La Fondazione-1975, page 554</ref> but more advanced [[compound microscope]]s first appeared in Europe around 1620<ref>{{cite book|author1=Albert Van Helden|author2=Sven Dupr\u00e9|author3=Rob van Gent|title=The Origins of the Telescope|url=https://books.google.com/books?id=XguxYlYd-9EC&pg=PA24|year=2010|publisher=Amsterdam University Press|isbn=978-90-6984-615-6|page=24|url-status=live|archive-url=https://web.archive.org/web/20170215200146/https://books.google.com/books?id=XguxYlYd-9EC&pg=PA24|archive-date=15 February 2017|df=dmy-all}}</ref><ref>William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, page 391 - 392</ref> The earliest practitioners of microscopy include [[Galileo Galilei]], who found in 1610 that he could close focus his telescope to view small objects close up<ref>Robert D. Huerta, Giants of Delft: Johannes Vermeer and the Natural Philosophers : the Parallel Search for Knowledge During the Age of Discovery, Bucknell University Press - 2003, page 126</ref><ref>A. Mark Smith, From Sight to Light: The Passage from Ancient to Modern Optics, University of Chicago Press - 2014, page 387</ref> and [[Cornelis Drebbel]], who may have invented the compound microscope around 1620<ref name="Raymond J. Seeger 2016, page 24">Raymond J. Seeger, Men of Physics: Galileo Galilei, His Life and His Works, Elsevier - 2016, page 24</ref><ref name="J. William Rosenthal 1996, page 391">J. William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, page 391</ref> [[Antonie van Leeuwenhoek]] developed a very high magnification simple microscope in the 1670s and is often considered to be the first acknowledged [[list of microscopists|microscopist]] and [[microbiologist]].<ref name="BrianJFord_1992"/><ref>[[Nick Lane|Lane, Nick]] (6 March 2015). "The Unseen World: Reflections on Leeuwenhoek (1677) 'Concerning Little Animal'." ''Philos Trans R Soc Lond B Biol Sci''. 2015 Apr; 370 (1666): 20140344. [doi:10.1098/rstb.2014.0344]</ref>"}},
{"article_title": "Microscope", "pageid": "19568", "revid": "1059024357", "timestamp": "2021-12-07T00:17:06Z", "history_paths": [["Microscope --- Introduction ---", "History"]], "categories": ["microbiology equipment", "microscopes", "microscopy", "scientific instruments", "science and technology in the dutch republic", "1590s in the dutch republic", "1600s in the dutch republic", "17th-century introductions"], "heading_tree": {"Microscope --- Introduction ---": {"History": {"Rise of modern light microscopes": {}, "Electron microscopes": {}, "Scanning probe microscopes": {}, "Fluorescence microscopes": {}, "Super resolution microscopes": {}, "X-ray microscopes": {}}, "Types": {"Optical": {}, "Electron": {}, "Scanning probe": {}, "Other types": {"Mobile apps": {}}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microscope --- Introduction ---|History": "[[File:Old-microscopes.jpg|thumb|right|200px|18th-century microscopes from the [[Mus\u00e9e des Arts et M\u00e9tiers]], [[Paris]]]]\n{{See|Timeline of microscope technology|Optical microscope#History}}\nAlthough objects resembling lenses date back 4,000 years and there are [[Greeks|Greek]] accounts of the optical properties of water-filled spheres (5th century BC) followed by many centuries of writings on optics, the earliest known use of simple microscopes ([[magnifying glass]]es) dates back to the widespread use of lenses in [[eyeglasses]] in the 13th century.<ref name="Bardell2004">{{cite journal|last1=Bardell|first1=David|title=The Invention of the Microscope|journal=BIOS|date=May 2004|volume=75|issue=2|pages=78\u201384|jstor=4608700|doi=10.1893/0005-3155(2004)75<78:tiotm>2.0.co;2}}</ref><ref>''The history of the telescope'' by Henry C. King, Harold Spencer Jones Publisher Courier Dover Publications, 2003, pp. 25\u201327 {{ISBN|0-486-43265-3|978-0-486-43265-6}}</ref><ref>Atti Della Fondazione Giorgio Ronchi E Contributi Dell'Istituto Nazionale Di Ottica, Volume 30, La Fondazione-1975, p. 554</ref> The earliest known examples of compound microscopes, which combine an [[Objective (optics)|objective lens]] near the specimen with an [[eyepiece]] to view a [[real image]], appeared in Europe around 1620.<ref name="Murphy">{{cite book|last1=Murphy|first1=Douglas B.|last2=Davidson|first2=Michael W.|title=Fundamentals of light microscopy and electronic imaging|date=2011|publisher=Wiley-Blackwell|location=Oxford|isbn=978-0-471-69214-0|edition=2nd}}</ref> The inventor is unknown, even though many claims have been made over the years. Several revolve around the spectacle-making centers in the [[Netherlands]], including claims it was invented in 1590 by [[Zacharias Janssen]] (claim made by his son) or Zacharias' father, Hans Martens, or both,<ref>{{cite book|author=Sir Norman Lockyer|title=Nature Volume 14|url=https://books.google.com/books?id=yaNFAAAAYAAJ&q=Zacharias+Janssen+Inventor&pg=PA54|year=1876}}</ref><ref>{{cite book|author1=Albert Van Helden|author2=Sven Dupr\u00e9|author3=Rob van Gent|title=The Origins of the Telescope|url=https://books.google.com/books?id=XguxYlYd-9EC&pg=PA36|year=2010|publisher=Amsterdam University Press|isbn=978-90-6984-615-6|pages=32\u201336, 43}}</ref> claims it was invented by their neighbor and rival spectacle maker, [[Hans Lippershey]] (who applied for the first [[telescope]] patent in 1608),<ref>{{cite web|url=http://www.livescience.com/39649-who-invented-the-microscope.html|title=Who Invented the Microscope? |website=[[Live Science]] |date=14 September 2013 |access-date=31 March 2017}}</ref> and claims it was invented by [[expatriate]] [[Cornelis Drebbel]], who was noted to have a version in London in 1619.<ref>{{cite book|author1=Eric Jorink|title=Reading the Book of Nature in the Dutch Golden Age, 1575-1715|url=https://books.google.com/books?id=XAiEMHlll9QC&q=compound+microscope+Cornelis+Drebbel&pg=PA4|isbn=978-90-04-18671-2|date=2010-10-25}}</ref><ref>William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, pp. 391\u201392</ref> [[Galileo Galilei]] (also sometimes cited as compound microscope inventor) seems to have found after 1610 that he could close focus his telescope to view small objects and, after seeing a compound microscope built by Drebbel exhibited in Rome in 1624, built his own improved version.<ref>Raymond J. Seeger, Men of Physics: Galileo Galilei, His Life and His Works, Elsevier \u2013 2016, p. 24</ref><ref>J. William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, page 391</ref><ref>[http://abyss.uoregon.edu/~js/glossary/galileo.html uoregon.edu, Galileo Galilei (Excerpt from the Encyclopedia Britannica)]</ref> [[Giovanni Faber]] coined the name ''microscope'' for the compound microscope Galileo submitted to the [[Accademia dei Lincei]] in 1625<ref>{{cite book |author=Gould, Stephen Jay |title=The Lying Stones of Marrakech: Penultimate Reflections in Natural History |url=https://archive.org/details/isbn_9780095031417 |url-access=registration | chapter = Chapter 2: The Sharp-Eyed Lynx, Outfoxed by Nature |publisher=Harmony |location=New York |year=2000 |isbn=978-0-224-05044-9}}</ref> (Galileo had called it the ''occhiolino'' 'little eye').\n\n \n[[File:Binocular compound microscope, Carl Zeiss Jena, 1914 (6779276516).jpg|thumb|Carl Zeiss binocular compound microscope, 1914|upright]]\n\nThe first detailed account of the [[histology|microscopic anatomy]] of organic tissue based on the use of a microscope did not appear until 1644, in Giambattista Odierna's ''L'occhio della mosca'', or ''The Fly's Eye''.<ref name=Wootton>{{cite book |author=Wootton, David |title=Bad medicine: doctors doing harm since Hippocrates |publisher=Oxford University Press |location=Oxford [Oxfordshire] |year=2006 |page=110|isbn=978-0-19-280355-9 }}{{page needed|date=November 2013}}</ref>\n\nThe microscope was still largely a novelty until the 1660s and 1670s when naturalists in Italy, the Netherlands and England began using them to study biology. Italian scientist [[Marcello Malpighi]], called the father of [[histology]] by some historians of biology, began his analysis of biological structures with the lungs. The publication in 1665 of [[Robert Hooke]]'s ''[[Micrographia]]'' had a huge impact, largely because of its impressive illustrations. A significant contribution came from [[Antonie van Leeuwenhoek]] who achieved up to 300 times magnification using a simple single lens microscope.  He sandwiched a very small glass ball lens between the holes in two metal plates riveted together, and with an adjustable-by-screws needle attached to mount the specimen.<ref>{{cite web|url=http://www.smithsonianmag.com/science-nature/early-microscopes-revealed-new-world-tiny-living-things-180958912|title=Early Microscopes Revealed a New World of Tiny Living Things|author=Liz Logan|publisher=Smithsonian.com|date=27 April 2016|access-date=3 June 2016}}</ref> Then, Van Leeuwenhoek re-discovered [[red blood cell]]s (after [[Jan Swammerdam]]) and [[spermatozoon|spermatozoa]], and helped popularise the use of microscopes to view biological ultrastructure. On 9 October 1676, van Leeuwenhoek reported the discovery of micro-organisms.<ref name=Wootton/>\n\nThe performance of a light microscope depends on the quality and correct use of the [[Condenser (optics)|condensor]] lens system to focus light on the specimen and the objective lens to capture the light from the specimen and form an image.<ref name="Murphy" /> Early instruments were limited until this principle was fully appreciated and developed from the late 19th to very early 20th century, and until electric lamps were available as light sources. In 1893 [[August K\u00f6hler]] developed a key principle of sample illumination, [[K\u00f6hler illumination]], which is central to achieving the theoretical limits of resolution for the light microscope. This method of sample illumination produces even lighting and overcomes the limited contrast and resolution imposed by early techniques of sample illumination. Further developments in sample illumination came from the discovery of [[Phase-contrast microscopy|phase contrast]] by [[Frits Zernike]] in 1953, and [[Differential interference contrast microscopy|differential interference contrast]] illumination by [[Georges Nomarski]] in 1955; both of which allow imaging of unstained, transparent samples.\n\n {{See also|electron microscope}}\n[[File:Ernst Ruska Electron Microscope - Deutsches Museum - Munich-edit.jpg|thumb|Electron microscope constructed by [[Ernst Ruska]] in 1933]]\nIn the early 20th century a significant alternative to the light microscope was developed, an instrument that uses a beam of [[electron]]s rather than [[light]] to generate an image. The German physicist, [[Ernst Ruska]], working with electrical engineer [[Max Knoll]], developed the first prototype electron microscope in 1931, a [[transmission electron microscope]] (TEM). The transmission electron microscope works on similar principles to an optical microscope but uses electrons in the place of light and electromagnets in the place of glass lenses. Use of electrons, instead of light, allows for much higher resolution.\n\nDevelopment of the transmission electron microscope was quickly followed in 1935 by the development of the [[scanning electron microscope]] by [[Max Knoll]].<ref name="knoll">{{cite journal |last=Knoll |first=Max|year=1935 |title=Aufladepotentiel und Sekund\u00e4remission elektronenbestrahlter K\u00f6rper |journal=Zeitschrift f\u00fcr Technische Physik |volume=16|pages=467\u2013475}}</ref> Although TEMs were being used for research before WWII, and became popular afterwards, the SEM was not commercially available until 1965.\n\nTransmission electron microscopes became popular following the [[Second World War]]. Ernst Ruska, working at [[Siemens]], developed the first commercial transmission electron microscope and, in the 1950s, major scientific conferences on electron microscopy started being held. In 1965, the first commercial scanning electron microscope was developed by Professor Sir [[Charles Oatley]] and his postgraduate student Gary Stewart, and marketed by the [[Cambridge Instrument Company]] as the "Stereoscan".\n\nOne of the latest discoveries made about using an electron microscope is the ability to identify a virus.<ref>{{Cite journal|last1=Goldsmith|first1=Cynthia S.|last2=Miller|first2=Sara E.|date=2009-10-01|title=Modern Uses of Electron Microscopy for Detection of Viruses|journal=Clinical Microbiology Reviews|language=en|volume=22|issue=4|pages=552\u2013563|doi=10.1128/cmr.00027-09|issn=0893-8512|pmid=19822888|pmc=2772359}}</ref> Since this microscope produces a visible, clear image of small organelles, in an electron microscope there is no need for reagents to see the virus or harmful cells, resulting in a more efficient way to detect pathogens.\n\n {{See also|scanning probe microscope}}\nFrom 1981 to 1983 [[Gerd Binnig]] and [[Heinrich Rohrer]] worked at [[IBM]] in [[Zurich]], [[Switzerland]] to study the [[quantum tunnelling]] phenomenon. They created a practical instrument, a [[scanning probe microscope]] from quantum tunnelling theory, that read very small forces exchanged between a probe and the surface of a sample. The probe approaches the surface so closely that electrons can flow continuously between probe and sample, making a current from surface to probe. The microscope was not initially well received due to the complex nature of the underlying theoretical explanations.  In 1984 [[Jerry Tersoff]] and D.R. Hamann, while at AT&T's Bell Laboratories in [[Murray Hill, New Jersey]] began publishing articles that tied theory to the experimental results obtained by the instrument. This was closely followed in 1985 with functioning commercial instruments, and in 1986 with Gerd Binnig, Quate, and Gerber's invention of the [[atomic force microscope]], then Binnig's and Rohrer's Nobel Prize in Physics for the SPM.<ref name="Morita">{{cite book|last1=Morita|first1=Seizo|title=Roadmap of Scanning Probe Microscopy|date=2007|publisher=Springer-Verlag Berlin Heidelberg|location=Berlin, Heidelberg|isbn=978-3-540-34315-8}}</ref>\n\nNew types of scanning probe microscope have continued to be developed as the ability to machine ultra-fine probes and tips has advanced.\n\n \n{{See also|fluorescence microscope|immunofluorescence|confocal microscope}}\n\n[[File:Olympus-BX61-fluorescence microscope.jpg|thumb|upright|Fluorescence microscope with the filter cube turret above the objective lenses, coupled with a camera.]]\n\nThe most recent developments in light microscope largely centre on the rise of [[fluorescence microscope|fluorescence microscopy]] in [[biology]].<ref name=":0" /> During the last decades of the 20th century, particularly in the post-[[genome|genomic]] era, many techniques for fluorescent [[staining]] of [[cell (biology)|cellular]] structures were developed.<ref name=":0" /> The main groups of techniques involve targeted chemical staining of particular cell structures, for example, the chemical compound [[DAPI]] to label [[DNA]], use of antibodies conjugated to fluorescent reporters, see\n[[immunofluorescence]], and fluorescent proteins, such as [[green fluorescent protein]].<ref name=":1" /> These techniques use these different fluorophores for analysis of cell structure at a molecular level in both live and fixed samples.\n\nThe rise of fluorescence microscopy drove the development of a major modern microscope design, the [[confocal microscope]]. The principle was patented in 1957 by [[Marvin Minsky]], although [[laser]] technology limited practical application of the technique. It was not until 1978 when [[Thomas Cremer|Thomas]] and [[Christoph Cremer]] developed the first practical [[confocal laser scanning microscope]] and the technique rapidly gained popularity through the 1980s.\n\n {{Main|Super-resolution microscopy|Microscopy#Sub-diffraction techniques}}\nMuch current research (in the early 21st century) on optical microscope techniques is focused on development of [[superresolution]] analysis of fluorescently labelled samples. [[Microscopy#Structured illumination|Structured illumination]] can improve resolution by around two to four times and techniques like [[stimulated Emission Depletion microscopy|stimulated emission depletion (STED) microscopy]] are approaching the resolution of electron microscopes.<ref>{{Cite web|url=https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2014/advanced-chemistryprize2014.pdf|title=The Nobel Prize in Chemistry 2014 \u2013 Scientific Background|website=www.nobelprize.org|access-date=2018-03-20}}</ref>  This occurs because the diffraction limit is occurred from light or excitation, which makes the resolution must be doubled to become super saturated. Stefan Hell was awarded the 2014 Nobel Prize in Chemistry for the development of the STED technique, along with Eric Betzig and William Moerner who adapted fluorescence microscopy for single-molecule visualization.<ref>{{Cite web|url=https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2014/press.html|title=The Nobel Prize in Chemistry 2014|website=www.nobelprize.org|access-date=2018-03-20}}</ref>\n\n {{main|X-ray microscope}}\nX-ray microscopes are instruments that use electromagnetic radiation usually in the soft X-ray band to image objects. Technological advances in X-ray lens optics in the early 1970s made the instrument a viable imaging choice.<ref name="Erko">{{cite book|last1=Erko|first1=A.|title=Modern developments in X-ray and neutron optics|date=2008|publisher=Springer|location=Berlin|isbn=978-3-540-74561-7}}</ref> They are often used in tomography (see [[X-ray microtomography|micro-computed tomography]]) to produce three dimensional images of objects, including biological materials that have not been chemically fixed. Currently research is being done to improve optics for hard X-rays which have greater penetrating power.<ref name="Erko" />"}},
{"article_title": "Molecular nanotechnology", "pageid": "19637", "revid": "1053004390", "timestamp": "2021-11-01T10:15:00Z", "history_paths": [["Molecular nanotechnology --- Introduction ---"], ["Molecular nanotechnology --- Introduction ---", "Introduction"]], "categories": ["nanotechnology", "robotics", "emerging technologies", "self-replication"], "heading_tree": {"Molecular nanotechnology --- Introduction ---": {"Introduction": {}, "Projected applications and capabilities": {"Smart materials and nanosensors": {}, "Replicating nanorobots": {}, "Medical nanorobots": {}, "Utility fog": {}, "Phased-array optics": {}}, "Potential social impacts": {"Benefits": {}, "Risks": {}}, "Technical issues and criticism": {"Study and recommendations by the U.S. National Academy of Sciences": {}, "Assemblers versus nanofactories": {}, "Hard versus soft nanotechnology": {}, "The Smalley{{ndash}}Drexler debate": {}, "Redefining of the word \"nanotechnology\"": {}, "The feasibility of the proposals in ''Nanosystems''": {}, "Existing work on diamond mechanosynthesis": {}}, "Works of fiction": {}, "See also": {}, "References": {}, "Reference works": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Molecular nanotechnology --- Introduction ---": "{{Technical|article|date=March 2014}}\n{{short description|Technology}}\n{{Nanotech}}\n[[Image:Kinesin_walking.gif|thumb|300px| [[Kinesin]] is a [[protein complex]] functioning as a molecular [[biological machine]]. It uses [[protein dynamics#Global flexibility: multiple domains|protein domain dynamics]] on [[Nanoscopic scale|nanoscale]]s]]\n{{Molecular nanotechnology}}\n\n'''Molecular nanotechnology''' ('''MNT''') is a technology based on the ability to build structures to complex, atomic specifications by means of [[mechanosynthesis]].<ref>{{cite web|url=http://e-drexler.com/d/06/00/Nanosystems/glossary/glossary_n.html#Nanotechnology |title=Nanosystems Glossary |publisher=E-drexler.com }}</ref> This is distinct from [[Nanomaterials|nanoscale materials]].  Based on [[Richard Feynman]]'s vision of miniature factories using nanomachines to build complex products ([[self-replicating machine|including additional nanomachines]]), this advanced form of [[nanotechnology]] (or ''molecular manufacturing''<ref>{{cite web |url=http://wise-nano.org/w/Doing_MM |archive-url=https://web.archive.org/web/20051108122214/http://wise-nano.org/w/Doing_MM |url-status=dead |archive-date=2005-11-08 |title=Doing MM |publisher=Wise Nano |date=2008-09-24 |access-date=2010-09-05 }}</ref>) would make use of positionally-controlled mechanosynthesis guided by [[molecular machine]] systems. MNT would involve combining physical principles demonstrated by [[biophysics]], [[chemistry]], other nanotechnologies, and the [[Biological machine|molecular machinery of life]] with the systems engineering principles found in modern macroscale factories.\n[[Image:Protein translation.gif|thumb|300px| A [[ribosome]] is a [[biological machine]].]]\n\n While conventional chemistry uses inexact processes obtaining inexact results, and biology exploits inexact processes to obtain definitive results, molecular nanotechnology would employ original definitive processes to obtain definitive results. The desire in molecular nanotechnology would be to balance molecular reactions in positionally-controlled locations and orientations to obtain desired chemical reactions, and then to build systems by further assembling the products of these reactions.\n\nA roadmap for the development of MNT is an objective of a broadly based technology project led by [[Battelle Memorial Institute|Battelle]] (the manager of several U.S. National Laboratories) and the [[Foresight Institute]].<ref>{{cite web |url=http://www.foresight.org/cms/press_center/282 |title=Foresight Institute press release |publisher=Foresight.org |date=2008-01-29 |access-date=2010-09-05 |url-status=dead |archive-url=https://web.archive.org/web/20100923024525/http://foresight.org/cms/press_center/282 |archive-date=2010-09-23 }}</ref> The roadmap was originally scheduled for completion by late 2006, but was released in January 2008.<ref>{{cite web|last=Peterson |first=Christine |url=http://www.foresight.org/nanodot/?p=2478#more-2478 |title=Nanodot: Nanotechnology News and Discussion \u00bb Blog Archive \u00bb Nanotechnology Roadmap launch: Productive Nanosystems Conference, Oct 9-10 |publisher=Foresight.org |date=2007-05-08 |access-date=2010-09-05}}</ref> The Nanofactory Collaboration<ref name="autogenerated3">{{cite web|url=http://www.MolecularAssembler.com/Nanofactory |title=Nanofactory Collaboration |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> is a more focused ongoing effort involving 23 researchers from 10 organizations and 4 countries that is developing a practical research agenda<ref name="autogenerated2">{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/Challenges.htm |title=Nanofactory Technical Challenges |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> specifically aimed at positionally-controlled diamond mechanosynthesis and diamondoid nanofactory development. In August 2005, a task force consisting of 50+ international experts from various fields was organized by the [http://www.crnano.org/ Center for Responsible Nanotechnology] to study the societal implications of molecular nanotechnology.<ref>{{cite web|url=http://www.crnano.org|title=Global Task Force on Implications and Policy |publisher=Crnano.org |access-date=2010-09-05}}</ref>\n\n \n Any sort of material designed and engineered at the [[nanometer]] scale for a specific task is a [[smart material]].  If materials could be designed to respond differently to various molecules, for example, artificial drugs could recognize and render inert specific [[viruses]].  [[Self-healing material|self-healing structures]] would [[Regeneration (biology)|repair]] small tears in a surface naturally in the same way as human skin.\n\nA nanosensor would resemble a smart material, involving a small component within a larger machine that would react to its environment and change in some fundamental, intentional way.  A very simple example: a photosensor might passively measure the incident light and discharge its absorbed energy as electricity when the light passes above or below a specified threshold, sending a signal to a larger machine.  Such a sensor would supposedly cost less{{according to whom|date=June 2019}} and use less power than a conventional sensor, and yet function usefully in all the same applications — for example, turning on parking lot lights when it gets dark.\n\nWhile smart materials and nanosensors both exemplify useful applications of MNT, they pale in comparison with the complexity of the technology most popularly associated with the term: the replicating [[nanorobot]].\n\n \nMNT nanofacturing is popularly linked with the idea of [[swarm intelligence|swarm]]s of coordinated nanoscale robots working together, a popularization of an early proposal by [[K. Eric Drexler]] in his [[Engines of Creation|1986 discussions of MNT]], but [http://www.e-drexler.com/d/06/00/Nanosystems/toc.html superseded in 1992]. In this early proposal, sufficiently capable nanorobots would construct more nanorobots in an artificial environment containing special molecular building blocks.\n\nCritics have doubted both the feasibility of self-replicating [[nanorobot]]s and the feasibility of control if self-replicating nanorobots could be achieved: they cite the possibility of [[mutation]]s removing any control and favoring reproduction of mutant pathogenic variations.  Advocates address the first doubt by pointing out that the first macroscale autonomous machine replicator, made of [[Lego blocks]], was built and operated experimentally in 2002.<ref>{{cite web|url=http://www.MolecularAssembler.com/KSRM/3.23.4.htm |title=3.23.4 |publisher=Molecularassembler.com |date=2005-08-01 |access-date=2010-09-05}}</ref>  While there are sensory advantages present at the macroscale compared to the limited sensorium available at the nanoscale, proposals for positionally controlled nanoscale mechanosynthetic fabrication systems employ dead reckoning of tooltips combined with reliable reaction sequence design to ensure reliable results, hence a limited sensorium is no handicap;  similar considerations apply to the positional assembly of small nanoparts.  Advocates address the second doubt by arguing that [[bacterium|bacteria]] are (of necessity) evolved to evolve, while nanorobot mutation could be actively prevented by common [[Error-correction|error-correcting]] techniques. Similar ideas are advocated in the Foresight Guidelines on Molecular Nanotechnology,<ref name="autogenerated1">{{cite web|url=http://www.foresight.org/guidelines/index.html |title=Molecular Nanotechnology Guidelines |publisher=Foresight.org |access-date=2010-09-05}}</ref> and a map of the 137-dimensional replicator design space<ref>{{cite web|url=http://www.MolecularAssembler.com/KSRM/5.1.9.htm |title=5.1.9 |publisher=Molecularassembler.com |date=2005-08-01 |access-date=2010-09-05}}</ref> recently published by Freitas and Merkle provides numerous proposed methods by which replicators could, in principle, be safely controlled by good design.\n\nHowever, the concept of suppressing mutation raises the question: How can design evolution occur at the nanoscale without a process of random mutation and deterministic selection? Critics argue that MNT advocates have not provided a substitute for such a process of evolution in this nanoscale arena where conventional sensory-based selection processes are lacking.  The limits of the sensorium available at the nanoscale could make it difficult or impossible to winnow successes from failures.  Advocates argue that design evolution should occur deterministically and strictly under human control, using the conventional engineering paradigm of modeling, design, prototyping, testing, analysis, and redesign.\n\nIn any event, since 1992 [http://www.e-drexler.com/d/06/00/Nanosystems/toc.html technical proposals for MNT] do not include self-replicating nanorobots, and recent ethical guidelines put forth by MNT advocates prohibit unconstrained self-replication.<ref name="autogenerated1" /><ref>{{cite web|url=http://www.rfreitas.com/Nano/MMDangerous.pdf |title=N04FR06-p.15.pmd |access-date=2010-09-05}}</ref>\n\n \nOne of the most important applications of MNT would be medical [[nanorobotics]] or [[nanomedicine]], an area pioneered by [[Robert Freitas]] in numerous books<ref>{{cite web|url=http://www.nanomedicine.com |title=NanomedicineBookSite |publisher=Nanomedicine.com |access-date=2010-09-05}}</ref> and papers.<ref>{{cite web|url=http://www.rfreitas.com/NanoPubls.htm |title=NanoPubls |publisher=Rfreitas.com |access-date=2010-09-05}}</ref>  The ability to design, build, and deploy large numbers of medical nanorobots would, at a minimum, make possible the rapid elimination of disease and the reliable and relatively painless recovery from physical trauma.  Medical nanorobots might also make possible the convenient correction of genetic defects, and help to ensure a greatly expanded lifespan.  More controversially, medical nanorobots might be used to [[Human enhancement|augment natural human capabilities]]. One study has reported on how conditions like tumors, [[arteriosclerosis]], [[blood clots]] leading to stroke, accumulation of scar tissue and localized pockets of infection can possibly be addressed by employing medical nanorobots.<ref>{{cite web|url=http://www.foresight.org/Conferences/MNT8/Papers/Rubinstein/|title=NanoRobot for Treatment of Various Medical Problems|website=foresight.org|access-date=2017-09-12}}</ref><ref>{{cite journal|last1=Saadeh|first1=Yamaan|last2=Vyas|first2=Dinesh|date=June 2014|title=Nanorobotic Applications in Medicine: Current Proposals and Designs|journal=American Journal of Robotic Surgery|volume=1|issue=1|pages=4\u201311|doi=10.1166/ajrs.2014.1010|issn=2374-0612|pmc=4562685|pmid=26361635}}</ref>\n\n \n[[Image:Foglet.jpg|thumb|Diagram of a 100 micrometer foglet]]\nAnother proposed application of molecular nanotechnology is "[[utility fog]]"<ref>{{cite web |url=http://discuss.foresight.org/~josh/Ufog.html |title=Archived copy |access-date=2010-03-19 |url-status=dead |archive-url=https://web.archive.org/web/20061111094117/http://discuss.foresight.org/%7Ejosh/Ufog.html |archive-date=2006-11-11 }}</ref> — in which a cloud of networked microscopic robots (simpler than [[Molecular assembler|assembler]]s) would change its shape and properties to form macroscopic objects and tools in accordance with software commands.  Rather than modify the current practices of consuming material goods in different forms, utility fog would simply replace many physical objects.\n\n \nYet another proposed application of MNT would be [[phased-array optics]] (PAO).<ref>{{cite web|url=http://www.phased-array.com |title=Phased Array Optics |publisher=Phased-array.com |access-date=2010-09-05}}</ref>  However, this appears to be a problem addressable by ordinary nanoscale technology. PAO would use the principle of phased-array millimeter technology but at optical wavelengths.  This would permit the duplication of any sort of optical effect but virtually.  Users could request holograms, sunrises and sunsets, or floating lasers as the mood strikes.  PAO systems were described in BC Crandall's ''Nanotechnology:  Molecular Speculations on Global Abundance'' in the [[Brian Wowk]] article "Phased-Array Optics."<ref>{{cite web|url=http://www.phased-array.com/1996-Book-Chapter.html |title=Phased Array Optics |publisher=Phased-array.com |date=1991-10-03 |access-date=2010-09-05}}</ref>\n\n \n[[Molecular manufacturing]] is a potential future subfield of nanotechnology that would make it possible to  build complex structures at atomic precision.<ref name="Foresight nano FAQ">{{cite web|title=Frequently Asked Questions - Molecular Manufacturing|url=http://www.foresight.org/nano/whatismm.html|website=foresight.org|access-date=19 July 2014|url-status=dead|archive-url=https://web.archive.org/web/20140426045511/http://www.foresight.org/nano/whatismm.html|archive-date=26 April 2014}}</ref> Molecular manufacturing requires significant advances in nanotechnology, but once achieved could produce highly advanced products at low costs and in large quantities in nanofactories weighing a kilogram or more.<ref name="Foresight nano FAQ"/><ref name="GCRs nano-chapter"/> When nanofactories gain the ability to produce other nanofactories production may only be limited by relatively abundant factors such as input materials, energy and software.<ref name="GCRs nano-chapter"/>\n\nThe products of molecular manufacturing could range from cheaper, mass-produced versions of known high-tech products to novel products with added capabilities in many areas of application. Some applications that have been suggested are advanced [[smart materials]], nanosensors, medical nanorobots and space travel.<ref name="Foresight nano FAQ"/> Additionally, molecular manufacturing could be used to cheaply produce highly advanced, durable weapons, which is an area of special concern regarding the impact of nanotechnology.<ref name="GCRs nano-chapter">{{cite book|author1=Chris Phoenix|author2=Mike Treder|editor1-last=Bostrom|editor1-first=Nick|editor2-last=Cirkovic|editor2-first=Milan M.|title=Global catastrophic risks|date=2008|publisher=Oxford University Press|location=Oxford|isbn=978-0-19-857050-9|chapter=Chapter 21: Nanotechnology as global catastrophic risk}}</ref>  Being equipped with compact computers and motors these could be increasingly autonomous and have a large range of capabilities.<ref name="GCRs nano-chapter"/>\n\nAccording to Chris Phoenix and Mike Treder from the [[Center for Responsible Nanotechnology]] as well as Anders Sandberg from the [[Future of Humanity Institute]] molecular manufacturing is the application of nanotechnology that poses the most significant [[global catastrophic risk]].<ref name="GCRs nano-chapter"/><ref name = "Sandberg xrisk">{{cite web |last1=Sandberg |first1=Anders |title=The five biggest threats to human existence |url=http://theconversation.com/the-five-biggest-threats-to-human-existence-27053|website=theconversation.com/ |access-date=13 July 2014}}</ref> Several nanotechnology researchers state that the bulk of risk from nanotechnology comes from the potential to lead to war, arms races and destructive global government.<ref name="GCRs nano-chapter"/><ref name="Sandberg xrisk"/><ref>{{cite web|last1=Drexler|first1=Eric|title=A Dialog on Dangers |url=http://www.foresight.org/Updates/Background3.html#DangerDialog|website=foresight.org|access-date=19 July 2014}}</ref> Several reasons have been suggested why the availability of nanotech weaponry may with significant likelihood lead to unstable arms races (compared to e.g. nuclear arms races): (1) A large number of players may be tempted to enter the race since the threshold for doing so is low;<ref name="GCRs nano-chapter"/> (2) the ability to make weapons with molecular manufacturing will be cheap and easy to hide;<ref name="GCRs nano-chapter"/> (3) therefore lack of insight into the other parties' capabilities can tempt players to arm out of caution or to launch preemptive strikes;<ref name="GCRs nano-chapter"/><ref>{{cite web|last1=Drexler|first1=Eric|title=ENGINES OF DESTRUCTION (Chapter 11)|url=http://e-drexler.com/d/06/00/EOC/EOC_Chapter_11.html|website=e-drexler.com/|access-date=19 July 2014}}</ref> (4) molecular manufacturing may reduce dependency on international trade,<ref name="GCRs nano-chapter"/> a potential peace-promoting factor;<ref name="Tomasik promote compr">{{cite web|last1=Tomasik|first1=Brian|title=Possible Ways to Promote Compromise|url=http://foundational-research.org/publications/possible-ways-to-promote-compromise/#Democracy_trade_and_social_stability|website=foundational-research.org/|access-date=19 July 2014}}</ref> (5) [[wars of aggression]] may pose a smaller economic threat to the aggressor since manufacturing is cheap and humans may not be needed on the battlefield.<ref name="GCRs nano-chapter"/>\n\nSince self-regulation by all state and non-state actors seems hard to achieve,<ref>{{cite web|title=Dangers of Molecular Manufacturing|url=http://www.crnano.org/dangers.htm|website=crnano.org|access-date=19 July 2014}}</ref> measures to mitigate war-related risks have mainly been proposed in the area of [[Multilateralism|international cooperation]].<ref name="GCRs nano-chapter"/><ref name = "crnano int control">{{cite web|title=The Need for International Control|url=http://www.crnano.org/int_control.htm|website=crnano.org|access-date=19 July 2014}}</ref> International infrastructure may be expanded giving more sovereignty to the international level. This could help coordinate efforts for arms control.<ref name="Tomasik co-op vs arms race">{{cite web|last1=Tomasik|first1=Brian|title=International Cooperation vs. AI Arms Race|url=http://foundational-research.org/publications/international-cooperation-vs-ai-arms-race/#Nanotech_arms_races|website=foundational-research.org|access-date=19 July 2014}}</ref> International institutions dedicated specifically to nanotechnology (perhaps analogously to the International Atomic Energy Agency [[IAEA]]) or general arms control may also be designed.<ref name = "crnano int control"/> One may also jointly make [[Differential technological development|differential technological progress]] on defensive technologies, a policy that players should usually favour.<ref name="GCRs nano-chapter"/> The Center for Responsible Nanotechnology also suggest some technical restrictions.<ref>{{cite web|title=Technical Restrictions May Make Nanotechnology Safer|url=http://www.crnano.org/restrictions.htm|website=crnano.org|access-date=19 July 2014}}</ref> Improved transparency regarding technological capabilities may be another important facilitator for arms-control.<ref name="Tomasik promote compr 2">{{cite web|last1=Tomasik|first1=Brian|title=Possible Ways to Promote Compromise|url=http://foundational-research.org/publications/possible-ways-to-promote-compromise/#Transparency_social_capital_and_karma|website=foundational-research.org/|access-date=22 July 2014}}</ref>\n\nA [[grey goo]] is another catastrophic scenario, which was proposed by [[K. Eric Drexler|Eric Drexler]] in his 1986 book ''[[Engines of Creation]]'',<ref>{{cite book |title= Apocalypse 2012 |last= Joseph |first= Lawrence E. |year= 2007 |publisher= Broadway |location= New York |isbn= 978-0-7679-2448-1 |page= [https://archive.org/details/apocalypse2012sc00jose/page/6 6] |url= https://archive.org/details/apocalypse2012sc00jose/page/6 |url-access= registration }}</ref> has been analyzed by Freitas in "Some Limits to Global Ecophagy by Biovorous Nanoreplicators, with Public Policy Recommendations" <ref>{{Cite web | url=http://www.foresight.org/nano/Ecophagy.html | title=Some Limits to Global Ecophagy by Biovorous Nanoreplicators, with Public Policy Recommendations}}</ref> and has been a theme in mainstream media and fiction.<ref>{{cite news |url=http://news.bbc.co.uk/2/hi/science/nature/3788673.stm| title=Nanotech guru turns back on 'goo'| work= BBC News|access-date=2012-03-30|first=Paul|last=Rincon|date=2004-06-09}}</ref><ref>{{cite journal |last=Hapgood |first=Fred |date=November 1986 |title=Nanotechnology: Molecular Machines that Mimic Life |url=http://metamodern.com/b/wp-content/uploads/docs/OMNI_TINYTECH.pdf |journal=Omni |access-date=19 July 2014 }}</ref> This scenario involves tiny self-replicating robots that consume the entire biosphere using it as a source of energy and building blocks.  Nanotech experts including Drexler now discredit the scenario. According to  [[Chris Phoenix (nanotechnologist)|Chris Phoenix]] a "So-called grey goo could only be the product of a deliberate and difficult engineering process, not an accident".<ref>{{cite web|title=Leading nanotech experts put 'grey goo' in perspective|url=http://www.crnano.org/PR-IOP.htm|website=crnano.org|access-date=19 July 2014}}</ref> With the advent of nano-biotech, a different scenario called [[green goo]] has been forwarded. Here, the malignant substance is not nanobots but rather self-replicating biological [[organism]]s engineered through nanotechnology.\n\n \n<blockquote>\nNanotechnology (or molecular nanotechnology to refer more specifically to the goals discussed here) will let us continue the historical trends in manufacturing right up to the fundamental limits imposed by physical law. It will let us make remarkably powerful molecular computers. It will let us make materials over fifty times lighter than steel or aluminium alloy but with the same strength. We'll be able to make jets, rockets, cars or even chairs that, by today's standards, would be remarkably light, strong, and inexpensive. Molecular surgical tools, guided by molecular computers and injected into the blood stream could find and destroy cancer cells or invading bacteria, unclog arteries, or provide oxygen when the circulation is impaired.\n</blockquote>\n\n<blockquote>\nNanotechnology will replace our entire manufacturing base with a new, radically more precise, radically less expensive, and radically more flexible way of making products. The aim is not simply to replace today's computer chip making plants, but also to replace the assembly lines for cars, televisions, telephones, books, surgical tools, missiles, bookcases, airplanes, tractors, and all the rest. The objective is a pervasive change in manufacturing, a change that will leave virtually no product untouched. Economic progress and military readiness in the 21st Century will depend fundamentally on maintaining a competitive position in nanotechnology.\n\n<ref>{{cite web | url = http://www.merkle.com/papers/nanohearing1999.html \n  | title = Nanotechnology: the coming revolution in manufacturing, Testimony to the U.S. House of Representatives Committee on Science, Subcommittee on Basic Research\n  | first = Ralph\n  | last = Merkle\n  | date = 22 June 1999\n   }}</ref>\n\n</blockquote>\n\nDespite the current early developmental status of nanotechnology and molecular nanotechnology,  much concern surrounds MNT's anticipated impact on [[economics]]<ref>{{cite web|url=http://www.rfreitas.com/Nano/NoninflationaryPN.pdf |title=N20FR06-p._.pmd |access-date=2010-09-05}}</ref><ref>{{Cite web | url=http://lifeboat.com/ex/corporate.cornucopia | title=Corporate Cornucopia: Examining the Special Implications of Commercial MNT Development}}</ref> and on [[law]]. Whatever the exact effects, MNT, if achieved, would tend to reduce the [[scarcity]] of manufactured goods and make many more goods (such as food and health aids) manufacturable.\n\nMNT should make possible [[Nanomedicine|nanomedical]] capabilities able to cure any medical condition not already cured by advances in other areas. Good health would be common, and poor health of any form would be as rare as [[smallpox]] and [[scurvy]] are today. Even [[cryonics]] would be feasible, as [[cryopreserved]] tissue could be fully repaired.\n\n Molecular nanotechnology is one of the technologies that some analysts believe could lead to a [[technological singularity]], in which technological growth has accelerated to the point of having unpredictable effects. Some effects could be beneficial, while others could be detrimental, such as the utilization of molecular nanotechnology by an unfriendly [[artificial general intelligence]].<ref>{{Cite book|last=Yudkowsky|first=Eliezer|title=Global catastrophic risks|publisher=Oxford University Press|year=2008|isbn=978-0-19-960650-4|editor-last=Bostrom|editor-first=Nick|location=New York|pages=308\u2013345|chapter=Artificial Intelligence as a Positive and Negative Factor in Global Risk|oclc=993268361|editor-last2=\u0106irkovi\u0107|editor-first2=Milan M.}}</ref> \nSome feel that molecular nanotechnology would have daunting risks.<ref>{{cite web|url=http://www.crnano.org/dangers.htm |title=Nanotechnology: Dangers of Molecular Manufacturing |publisher=Crnano.org |access-date=2010-09-05}}</ref> It conceivably could enable cheaper and more destructive conventional [[weapon]]s.  Also, molecular nanotechnology might permit [[weapons of mass destruction]] that could self-replicate, as [[virus (biology)|virus]]es and [[cancer]] cells do when attacking the human body. Commentators generally agree that, in the event molecular nanotechnology were developed, its [[self-replication]] should be permitted only under very controlled or "inherently safe" conditions.\n\nA fear exists that nanomechanical robots, if achieved, and if designed to self-replicate using naturally occurring materials (a difficult task), could consume the entire planet in their hunger for raw materials,<ref>{{cite web|url=http://www.rfreitas.com/Nano/Ecophagy.htm |title=Some Limits to Global Ecophagy |publisher=Rfreitas.com |access-date=2010-09-05}}</ref> or simply crowd out natural life, out-competing it for energy (as happened historically when [[blue-green algae]] appeared and outcompeted earlier life forms).  Some commentators have referred to this situation as the "[[grey goo]]" or "[[ecophagy]]" scenario.  [[K. Eric Drexler]] considers an accidental "grey goo" scenario extremely unlikely and says so in later editions of ''Engines of Creation''.\n\nIn light of this perception of potential danger, the [[Foresight Institute]], founded by Drexler, has prepared a set of guidelines<ref>{{cite web|url=http://www.foresight.org/guidelines/current.html |title=Foresight Guidelines on Molecular Nanotechnology |publisher=Foresight.org |date=2006-04-06 |access-date=2010-09-05}}</ref> for the ethical development of nanotechnology.  These include the banning of free-foraging self-replicating pseudo-organisms on the Earth's surface, at least, and possibly in other places.\n\n The feasibility of the basic technologies analyzed in ''Nanosystems'' has been the subject of a formal scientific review by U.S. National Academy of Sciences, and has also been the focus of extensive debate on the internet and in the popular press.\n\n \nIn 2006, U.S. National Academy of Sciences released the report of a study of molecular manufacturing as part of a longer report, ''A Matter of Size: Triennial Review of the National Nanotechnology Initiative''<ref name="nanotechnology1">{{cite book|url=http://www.nap.edu/catalog/11752.html |title=A Matter of Size: Triennial Review of the National Nanotechnology Initiative |publisher=Nap.edu |access-date=2010-09-05|doi=10.17226/11752 |year=2006 |isbn=978-0-309-10223-0 }}</ref> The study committee reviewed the technical content of ''Nanosystems'', and in its conclusion states that no current theoretical analysis can be considered definitive regarding several questions of potential system performance, and that optimal paths for implementing high-performance systems cannot be predicted with confidence. It recommends experimental research to advance knowledge in this area:\n\n:"Although theoretical calculations can be made today, the eventually attainable range of chemical reaction cycles, error rates, speed of operation, and thermodynamic efficiencies of such bottom-up manufacturing systems cannot be reliably predicted at this time. Thus, the eventually attainable perfection and complexity of manufactured products, while they can be calculated in theory, cannot be predicted with confidence. Finally, the optimum research paths that might lead to systems which greatly exceed the thermodynamic efficiencies and other capabilities of biological systems cannot be reliably predicted at this time. Research funding that is based on the ability of investigators to produce experimental demonstrations that link to abstract models and guide long-term vision is most appropriate to achieve this goal."\n\n A section heading in Drexler's ''[[Engines of Creation]]'' reads<ref>{{cite web|url=http://www.e-drexler.com/d/06/00/EOC/EOC_Cover.html |title=Engines of Creation - K. Eric Drexler : Cover |publisher=E-drexler.com |access-date=2010-09-05}}</ref> "Universal Assemblers", and the following text speaks of multiple types of [[Assembler (nanotechnology)|assemblers]] which, collectively, could hypothetically "build almost anything that the laws of nature allow to exist." Drexler's colleague [[Ralph Merkle]] has noted that, contrary to widespread legend,<ref>{{cite web|url=http://www.foresight.org/impact/impossible.html#Fear |title=How good scientists reach bad conclusions |publisher=Foresight.org |access-date=2010-09-05}}</ref> Drexler never claimed that assembler systems could build absolutely any molecular structure. The endnotes in Drexler's book explain the qualification "almost": "For example, a delicate structure might be designed that, like a stone arch, would self-destruct unless all its pieces were already in place. If there were no room in the design for the placement and removal of a scaffolding, then the structure might be impossible to build. Few structures of practical interest seem likely to exhibit such a problem, however."\n\nIn 1992, Drexler published ''Nanosystems: Molecular Machinery, Manufacturing, and Computation'',<ref>{{cite web|url=http://www.e-drexler.com/d/06/00/Nanosystems/toc.html |title=Nanosystems TOC |publisher=E-drexler.com |date=2002-11-01 |access-date=2010-09-05}}</ref> a detailed proposal for synthesizing stiff covalent structures using a table-top factory. [[Diamondoid]] structures and other stiff covalent structures, if achieved, would have a wide range of possible applications, going far beyond current [[Microelectromechanical systems|MEMS]] technology. An outline of a path was put forward in 1992 for building a table-top factory in the absence of an assembler. Other researchers have begun advancing tentative, alternative proposed paths <ref name="autogenerated3" /> for this in the years since Nanosystems was published.\n\n In 2004 Richard Jones wrote Soft Machines (nanotechnology and life), a book for lay audiences published by [[Oxford University]]. In this book he describes radical nanotechnology (as advocated by Drexler) as a deterministic/mechanistic idea of nano engineered  machines that does not take into account the nanoscale challenges such as [[wetness]], [[Adhesion|stickiness]], [[Brownian motion]], and high [[viscosity]]. He also explains what is soft nanotechnology or more appropriately [[biomimetic]] nanotechnology which is the way forward, if not the best way, to design functional nanodevices that can cope with all the problems at a nanoscale. One can think of soft nanotechnology as the development of nanomachines that uses the lessons learned from biology on how things work, chemistry to precisely engineer such devices and stochastic physics to model the system and its natural processes in detail.\n\n {{main|Drexler\u2013Smalley debate on molecular nanotechnology}}\n\nSeveral researchers, including Nobel Prize winner [[Richard Smalley|Dr. Richard Smalley]] (1943\u20132005),<ref>{{cite journal| url=http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=F90C4210-C153-4B2F-83A1-28F2012B637| date=September 2001| journal=Scientific American| title=Of Chemistry, Love and Nanobots| first=Richard E.| last=Smalley| doi=10.1038/scientificamerican0901-76| pmid=11524973| volume=285| issue=3| pages=76\u201377| bibcode=2001SciAm.285c..76S| access-date=2007-04-15| archive-url=https://web.archive.org/web/20120723062135/http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=F90C4210-C153-4B2F-83A1-28F2012B637| archive-date=2012-07-23| url-status=dead}}</ref> attacked the notion of universal assemblers, leading to a rebuttal from Drexler and colleagues,<ref>{{cite web|url=http://www.imm.org/SciAmDebate2/smalley.php |title=Debate About Assemblers \u2014 Smalley Rebuttal |publisher=Imm.org |access-date=2010-09-05}}</ref> and eventually to an exchange of letters.<ref>{{cite web|url=http://pubs.acs.org/cen/coverstory/8148/8148counterpoint.html |title=C&En: Cover Story - Nanotechnology |publisher=Pubs.acs.org |date=2003-12-01 |access-date=2010-09-05}}</ref> Smalley argued that chemistry is extremely complicated, reactions are hard to control, and that a universal assembler is science fiction. Drexler and colleagues, however, noted that Drexler never proposed universal assemblers able to make absolutely anything, but instead proposed more limited assemblers able to make a very wide variety of things. They challenged the relevance of Smalley's arguments to the more specific proposals advanced in ''Nanosystems''.  Also, Smalley argued that nearly all of modern chemistry involves reactions that take place in a [[solvent]] (usually [[water]]), because the [[small molecules]] of a solvent contribute many things, such as lowering [[binding energies]] for transition states.  Since nearly all known chemistry requires a solvent, Smalley felt that Drexler's proposal to use a high vacuum environment was not feasible.  However, Drexler addresses this in Nanosystems by showing mathematically that well designed [[catalysts]] can provide the effects of a solvent and can fundamentally be made even more efficient than a solvent/[[enzyme]] reaction could ever be. It is noteworthy that, contrary to Smalley's opinion that enzymes require water, "Not only do enzymes work vigorously in anhydrous organic media, but in this unnatural milieu they acquire remarkable properties such as greatly enhanced stability, radically altered substrate and [[enantiomeric]] specificities, molecular memory, and the ability to catalyse unusual reactions."<ref>{{cite journal|title=Enzymatic catalysis in anhydrous organic solvents.|date=April 1989 | pmid=2658221 | doi=10.1016/0968-0004(89)90146-1|volume=14|issue=4 |journal=Trends Biochem Sci|pages=141\u20134 | last1 = Klibanov | first1 = AM}}"{{cite journal|title=Enzymatic catalysis in anhydrous organic solvents|date=April 1989 | pmc=397741|pmid=3858815|volume=82|issue = 10|journal=Proc. Natl. Acad. Sci. U.S.A.|pages=3192\u20136 | last1 = Zaks | first1 = A | last2 = Klibanov | first2 = AM|doi=10.1073/pnas.82.10.3192 |bibcode=1985PNAS...82.3192Z|doi-access=free }}</ref>\n\n For the future, some means have to be found for MNT design evolution at the nanoscale which mimics the process of biological evolution at the molecular scale. Biological evolution proceeds by random variation in ensemble averages of organisms combined with culling of the less-successful variants and reproduction of the more-successful variants, and macroscale engineering design also proceeds by a process of design evolution from simplicity to complexity as set forth somewhat satirically by [[John Gall (author)|John Gall]]: "A complex system that works is invariably found to have evolved from a simple system that worked.  . . . A complex system designed from scratch never works and can not be patched up to make it work. You have to start over, beginning with a system that works."<ref name="JohGall">\nGall, John, (1986) Systemantics: How Systems Really Work and How They Fail, 2nd ed. Ann Arbor, MI : The General Systemantics Press.</ref> A breakthrough in MNT is needed which proceeds from the simple atomic ensembles which can be built with, e.g., an STM to complex MNT systems via a process of design evolution. A handicap in this process is the difficulty of seeing and manipulation at the nanoscale compared to the macroscale which makes deterministic selection of successful trials difficult; in contrast biological evolution proceeds via action of what Richard Dawkins has called the "blind watchmaker"\n<ref name = "Dawkins">\nRichard Dawkins, The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe Without Design, W. W. Norton; Reissue edition (September 19, 1996)\n</ref> \ncomprising random molecular variation and deterministic reproduction/extinction.\n\nAt present in 2007 the practice of nanotechnology embraces both stochastic approaches (in which, for example, [[supramolecular chemistry]] creates waterproof pants) and deterministic approaches wherein single molecules (created by stochastic chemistry) are manipulated on substrate surfaces (created by stochastic deposition methods) by deterministic methods comprising nudging them with [[scanning tunneling microscope|STM]] or [[Atomic force microscope|AFM]] probes and causing simple binding or cleavage reactions to occur. The dream of a complex, deterministic molecular nanotechnology remains elusive.  Since the mid-1990s, thousands of surface scientists and thin film technocrats have latched on to the nanotechnology bandwagon and redefined their disciplines as nanotechnology.  This has caused much confusion in the field and has spawned thousands of "nano"-papers on the peer reviewed literature.  Most of these reports are extensions of the more ordinary research done in the parent fields.\n\n {{Multiple image\n|direction = vertical\n|image1 = Molecularpropeller.jpg\n|image2 = Nanob.jpg\n|footer = Top, a molecular propellor. Bottom, a molecular [[planetary gear]] system. The feasibility of devices like these has been questioned.}}\n\nThe feasibility of Drexler's proposals largely depends, therefore, on whether designs like those in ''Nanosystems'' could be built in the absence of a universal assembler to build them and would work as described. Supporters of molecular nanotechnology frequently claim that no significant errors have been discovered in ''Nanosystems'' since 1992. Even some critics concede<ref>{{cite web|url=http://www.softmachines.org/wordpress/index.php?p=50#comment-523 |title=Blog Archive \u00bb Is mechanosynthesis feasible? The debate moves up a gear |publisher=Soft Machines |date=2004-12-16 |access-date=2010-09-05}}</ref> that "Drexler has carefully considered a number of physical principles underlying the 'high level' aspects of the nanosystems he proposes and, indeed, has thought in some detail" about some issues.\n\nOther critics claim, however, that ''Nanosystems'' omits important chemical details about the low-level 'machine language' of molecular nanotechnology.<ref>{{cite magazine|url=https://www.wired.com/wired/archive/12.10/drexler.html |title=Smalley |magazine=Wired |date= October 2004|access-date=2010-09-05|last1=Regis |first1=Ed }}</ref><ref>{{cite web|url=http://www.nanotech-now.com/Atkinson-Phoenix-Nanotech-Debate.htm |title=Atkinson |publisher=Nanotech-now.com |access-date=2010-09-05}}</ref><ref>{{cite web|url=http://www.softmachines.org/wordpress/index.php?p=70 |title=Moriarty |publisher=Softmachines.org |date=2005-01-26 |access-date=2010-09-05}}</ref><ref>{{cite web|url=http://www.softmachines.org/wordpress/?p=175 |title=Jones |publisher=Softmachines.org |date=2005-12-18 |access-date=2010-09-05}}</ref> They also claim that much of the other low-level chemistry in ''Nanosystems'' requires extensive further work, and that Drexler's higher-level designs therefore rest on speculative foundations.  Recent such further work by Freitas and Merkle <ref>{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/Publications.htm |title=Nanofactory Collaboration Publications |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> is aimed at strengthening these foundations by filling the existing gaps in the low-level chemistry.\n\nDrexler argues that we may need to wait until our conventional [[nanotechnology]] improves before solving these issues: "Molecular manufacturing will result from a series of advances in molecular machine systems, much as the first Moon landing resulted from a series of advances in liquid-fuel [[rocket]] systems. We are now in a position like that of the [[British Interplanetary Society]] of the 1930s which described how multistage liquid-fueled rockets could reach the Moon and pointed to early rockets as illustrations of the basic principle."<ref>{{cite web|url=http://www.softmachines.org/PDFs/Moriarty_Phoenix_1.pdf |title=Moriarity Correspondence |access-date=2010-09-05}}</ref>  However, Freitas and Merkle argue <ref>{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/index.htm#NeedFund |title=Nanofactory Collaboration |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> that a focused effort to achieve diamond mechanosynthesis (DMS) can begin now, using existing technology, and might achieve success in less than a decade if their "direct-to-DMS approach is pursued rather than a more circuitous development approach that seeks to implement less efficacious nondiamondoid molecular manufacturing technologies before progressing to diamondoid".\n\nTo summarize the arguments against feasibility:  First, critics argue that a primary barrier to achieving molecular nanotechnology is the lack of an efficient way to create machines on a molecular/atomic scale, especially in the absence of a well-defined path toward a self-replicating assembler or diamondoid nanofactory. Advocates respond that a preliminary research path leading to a diamondoid nanofactory is being developed.<ref name="autogenerated2" />\n\nA second difficulty in reaching molecular nanotechnology is design.  Hand design of a gear or bearing at the level of atoms might take a few to several weeks. While Drexler, Merkle and others have created designs of simple parts, no comprehensive design effort for anything approaching the complexity of a Model T Ford has been attempted.  Advocates respond that it is difficult to undertake a comprehensive design effort in the absence of significant funding for such efforts, and that despite this handicap much useful design-ahead has nevertheless been accomplished with new software tools that have been developed, e.g., at Nanorex.<ref>{{cite web|url=http://nanoengineer-1.com/content/index.php?option=com_content&task=view&id=40&Itemid=50 |title=Nanorex, Inc. - Molecular Machinery Gallery |publisher=Nanoengineer-1.com |access-date=2010-09-05}}</ref>\n\nIn the latest report ''A Matter of Size: Triennial Review of the National Nanotechnology Initiative''<ref name="nanotechnology1"/> put out by the National Academies Press in December 2006 (roughly twenty years after Engines of Creation was published), no clear way forward toward molecular nanotechnology could yet be seen, as per the conclusion on page 108 of that report: "Although theoretical calculations can be made today, the eventually attainable\nrange of chemical reaction cycles, error rates, speed of operation, and thermodynamic\nefficiencies of such bottom-up manufacturing systems cannot be reliably\npredicted at this time. Thus, the eventually attainable perfection and complexity of\nmanufactured products, while they can be calculated in theory, cannot be predicted\nwith confidence. Finally, the optimum research paths that might lead to systems\nwhich greatly exceed the thermodynamic efficiencies and other capabilities of\nbiological systems cannot be reliably predicted at this time. Research funding that\nis based on the ability of investigators to produce experimental demonstrations\nthat link to abstract models and guide long-term vision is most appropriate to\nachieve this goal." This call for research leading to demonstrations is welcomed by groups such as the Nanofactory Collaboration who are specifically seeking experimental successes in diamond mechanosynthesis.<ref>{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/DMS.htm |title=Diamond Mechanosynthesis |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref>  The "Technology Roadmap for [[Productive nanosystems|Productive Nanosystems]]"<ref>{{cite web|url=http://www.foresight.org/roadmaps |title=Technology Roadmap for Productive Nanosystems |publisher=Foresight.org |access-date=2010-09-05}}</ref> aims to offer additional constructive insights.\n\nIt is perhaps interesting to ask whether or not most structures consistent with physical law can in fact be manufactured.  Advocates assert that to achieve most of the vision of molecular manufacturing it is not necessary to be able to build "any structure that is compatible with natural law." Rather, it is necessary to be able to build only a sufficient (possibly modest) subset of such structures\u2014as is true, in fact, of any practical manufacturing process used in the world today, and is true even in biology. In any event, as [[Richard Feynman]] once said, "It is scientific only to say what's more likely or less likely, and not to be proving all the time what's possible or impossible."<ref>[[Wikiquote:Richard Feynman]]</ref>\n\n \nThere is a growing body of peer-reviewed theoretical work on synthesizing diamond by mechanically removing/adding hydrogen atoms <ref>[http://www.MolecularAssembler.com/Papers/TemelsoHAbst.pdf High-level Ab Initio Studies of Hydrogen Abstraction from Prototype Hydrocarbon Systems]. Temelso, Sherrill, Merkle, and Freitas, ''J. Phys. Chem. A'' Vol. 110, pages 11160-11173, 2006.</ref> and depositing carbon atoms <ref>[http://www.rfreitas.com/Nano/JNNDimerTool.pdf Theoretical Analysis of a Carbon-Carbon Dimer Placement Tool for Diamond Mechanosynthesis]. Merkle and Freitas, ''J. Nanosci. Nanotech.'' Vol. 3, pages 319-324, 2003.</ref><ref>[http://www.MolecularAssembler.com/JCTNPengMar04.pdf Theoretical Analysis of Diamond Mechanosynthesis. Part I. Stability of C<sub>2</sub> Mediated Growth of Nanocrystalline Diamond C(110) Surface] {{webarchive|url=https://web.archive.org/web/20090316022613/http://www.molecularassembler.com/JCTNPengMar04.pdf |date=2009-03-16 }}. Peng, Freitas and Merkle. ''J. Comput. Theor. Nanosci.'' Vol. 1, pages 62-70, 2004.</ref><ref>[http://www.MolecularAssembler.com/JCTNMannMar04.pdf Theoretical Analysis of Diamond Mechanosynthesis. Part II. C<sub>2</sub> Mediated Growth of Diamond C(110) Surface via Si/Ge-Triadamantane Dimer Placement Tools] {{webarchive|url=https://web.archive.org/web/20090316022605/http://www.molecularassembler.com/JCTNMannMar04.pdf |date=2009-03-16 }}. Mann, Peng, Freitas and Merkle. ''J. Comput. Theor. Nanosci.'' Vol. 1, pages 71-80, 2004.</ref><ref>[http://e-drexler.com/d/05/00/DC10C-mechanosynthesis.pdf Design and Analysis of a Molecular Tool for Carbon Transfer in Mechanosynthesis]. Allis and Drexler. ''J. Comput. Theor. Nanosci.'' Vol. 2, pages 71-80, 2005.</ref><ref>[http://www.MolecularAssembler.com/Papers/JCTNPengFeb06.pdf Theoretical Analysis of Diamond Mechanosynthesis. Part III. Positional C<sub>2</sub> Deposition on Diamond C(110) Surface using Si/Ge/Sn-based Dimer Placement Tools]. Peng, Freitas, Merkle, Von Ehr, Randall and Skidmore. ''J. Comput. Theor. Nanosci.'' Vol. 3, pages 28-41, 2006.</ref><ref>[Horizontal Ge-Substituted Polymantane-Based C<sub>2</sub> Dimer Placement Tooltip Motifs for Diamond Mechanosynthesis]. Freitas, Allis and Merkle. ''J. Comput. Theor. Nanosci.'' Vol. 4, 2007, in press.</ref> (a process known as [[mechanosynthesis]]). This work is slowly permeating the broader nanoscience community and is being critiqued.  For instance, Peng et al. (2006)<ref>{{cite web|url=http://www.MolecularAssembler.com/Papers/JCTNPengFeb06.pdf |title=03CTN01-003 |access-date=2010-09-05}}</ref> (in the continuing research effort by Freitas, Merkle and their collaborators) reports that the most-studied mechanosynthesis tooltip motif (DCB6Ge) successfully places a C<sub>2</sub> carbon [[Dimer (chemistry)|dimer]] on a C(110) [[diamond]] surface at both 300 K (room temperature) and 80 K ([[liquid nitrogen]] temperature), and that the silicon variant (DCB6Si) also works at 80 K but not at 300 K. Over 100,000 CPU hours were invested in this latest study.  The DCB6 tooltip motif, initially described by Merkle and Freitas at a Foresight Conference in 2002, was the first complete tooltip ever proposed for diamond mechanosynthesis and remains the only tooltip motif that has been successfully simulated for its intended function on a full 200-atom diamond surface.\n\nThe tooltips modeled in this work are intended to be used only in carefully controlled environments (e. g., vacuum). Maximum acceptable limits for tooltip translational and rotational misplacement errors are reported in Peng et al. (2006) -- tooltips must be positioned with great accuracy to avoid bonding the dimer incorrectly.  Peng et al. (2006) reports that increasing the handle thickness from 4 support planes of C atoms above the tooltip to 5 planes decreases the resonance frequency of the entire structure from 2.0 THz to 1.8 THz.  More importantly, the vibrational footprints of a DCB6Ge tooltip mounted on a 384-atom handle and of the same tooltip mounted on a similarly constrained but much larger 636-atom "crossbar" handle are virtually identical in the non-crossbar directions. Additional computational studies modeling still bigger handle structures are welcome, but the ability to precisely position SPM tips to the requisite atomic accuracy has been repeatedly demonstrated experimentally at low temperature,<ref>{{cite web|url=http://www.physics.uci.edu/~wilsonho/stm-iets.html |title=Wilson Ho |publisher=Physics.uci.edu |access-date=2010-09-05}}</ref><ref>{{cite journal|journal=[[Physical Review Letters]]|volume=90|issue=17|page=176102|doi= 10.1103/PhysRevLett.90.176102|bibcode=2003PhRvL..90q6102O|title=Mechanical Vertical Manipulation of Selected Single Atoms by Soft Nanoindentation Using Near Contact Atomic Force Microscopy|pmid=12786084 | last1 = Oyabu | first1 = N | last2 = Custance | first2 = O | last3 = Yi | first3 = I | last4 = Sugawara | first4 = Y | last5 = Morita | first5 = S|year=2003| doi-access = free }}</ref> or even at room temperature<ref>{{cite journal|author=R. V. Lapshin|year=2004|title=Feature-oriented scanning methodology for probe microscopy and nanotechnology|journal=Nanotechnology|volume=15|issue=9|pages=1135\u20131151|issn=0957-4484|doi=10.1088/0957-4484/15/9/006|url=http://www.lapshin.fast-page.org/publications.htm#feature2004|format=PDF|bibcode=2004Nanot..15.1135L}}</ref><ref>{{cite book|author=R. V. Lapshin|year=2011|contribution=Feature-oriented scanning probe microscopy|title=Encyclopedia of Nanoscience and Nanotechnology|editor=H. S. Nalwa|volume=14|pages=105\u2013115|publisher=American Scientific Publishers|location=USA|isbn=978-1-58883-163-7|url=http://www.lapshin.fast-page.org/publications.htm#fospm2011|format=PDF}}</ref> constituting a basic existence proof for this capability.\n\nFurther research<ref>{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/AnnBibDMS.htm |title=DMS Bibliography |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> to consider additional tooltips will require time-consuming [[computational chemistry]] and difficult laboratory work.\n\nA working [[nanofactory]] would require a variety of well-designed tips for different reactions, and detailed analyses of placing atoms on more complicated surfaces. Although this appears a challenging problem given current resources, many tools will be available to help future researchers: [[Moore's law]] predicts further increases in computer power, [[Fabrication (semiconductor)|semiconductor fabrication]] techniques continue to approach the nanoscale, and researchers grow ever more skilled at using [[protein]]s, [[ribosome]]s and [[DNA]] to perform novel chemistry.\n\n *In ''[[The Diamond Age]]'' by [[Neal Stephenson]], diamond can be built directly out of carbon atoms. All sorts of devices from dust-size detection devices to giant diamond zeppelins are constructed atom by atom using only carbon, oxygen, nitrogen and chlorine atoms.\n*In the novel ''Tomorrow'' by Andrew Saltzman ({{ISBN|1-4243-1027-X}}), a scientist uses [[nanorobotics]] to create a liquid that when inserted into the [[bloodstream]], renders one nearly [[wikt:invincible|invincible]] given that the microscopic machines repair tissue almost instantaneously after it is damaged.\n*In the [[roleplaying game]] ''[[Splicers]]'' by [[Palladium Books]], humanity has succumbed to a "nanobot plague" that causes any object made of a non-[[precious metal]] to twist and change shape (sometimes into a type of [[robot]]) moments after being touched by a human.  The object will then proceed to attack the human.  This has forced humanity to develop "biotechnological" devices to replace those previously made of metal.\n* On the television show ''[[Mystery Science Theater 3000]]'', the [[Nanites]] (voiced variously by [[Kevin Murphy (actor)|Kevin Murphy]], [[Paul Chaplin (actor)|Paul Chaplin]], [[Mary Jo Pehl]], and [[Bridget Jones (actor)|Bridget Jones]]) \u2013 are self-replicating, bio-engineered organisms that work on the ship, they are microscopic creatures that reside in the Satellite of Love's computer systems. (They are similar to the creatures in ''[[Star Trek: The Next Generation]]'' episode "[[Evolution (TNG episode)|Evolution]]", which featured "nanites" taking over the ''Enterprise''.) The Nanites made their first appearance in season 8. Based on the concept of [[nanotechnology]], their comical ''[[deus ex machina]]'' activities included such diverse tasks as instant repair and construction, hairstyling, performing a Nanite variation of a [[flea circus]], conducting a microscopic war, and even destroying the Observers' planet after a dangerously vague request from Mike to "take care of [a] little problem". They also ran a [[microbrewery]].\n* Stargate Atlantis has an enemy made of self-assembling nanorobots, which also convert a planet into grey goo.\n* In the novel "Prey" by Michael Crichton, self replicating nanobots create autonomous nano-swarms with predatory behaviors. The protagonist must stop the swarm before it evolves into a grey goo plague.\n* In the films ''[[Avengers Infinity War]]'' and ''[[Avengers Endgame]]'' Tony Stark's Iron Man suit was constructed using nanotechnology.\n\n {{Portal|Science|Technology}}\n* [[Nanochemistry]]\n* [[Green nanotechnology]]\n* [[Technomimetics]]\n\n {{Reflist|30em}}\n\n *The primary technical reference work on this topic is [http://www.e-drexler.com/d/06/00/Nanosystems/toc.html ''Nanosystems: Molecular Machinery, Manufacturing, and Computation''], an in-depth, physics-based analysis of a particular class of potential nanomachines and molecular manufacturing systems, with extensive analyses of their feasibility and performance. ''Nanosystems'' is closely based on Drexler's MIT doctoral dissertation, [http://e-drexler.com/d/09/00/Drexler_MIT_dissertation.pdf "Molecular Machinery and Manufacturing with Applications to Computation"]. Both works also discuss technology development pathways that begin with scanning probe and biomolecular technologies.\n*Drexler and others extended the ideas of molecular nanotechnology with several other books. ''Unbounding the Future: the Nanotechnology Revolution'' <ref>{{cite web|url=http://www.foresight.org/UTF/Unbound_LBW/ |title=Unbounding the Future: Table of Contents |publisher=Foresight.org |access-date=2010-09-05}}</ref> and . ''Unbounding the Future'' is an easy-to-read book that introduces the ideas of molecular nanotechnology in a not-too-technical way. Other notable works in the same vein are [http://www.nanomedicine.com/ Nanomedicine Vol. I and Vol. IIA] by [[Robert Freitas]] and ''Kinematic Self-Replicating Machines'' {{cite web|url=http://www.MolecularAssembler.com/KSRM.htm |title=KSRM Table of Contents Page |publisher=Molecularassembler.com |access-date=2010-09-05}} by [[Robert Freitas]] and [[Ralph Merkle]].\n*''Nanotechnology:  Molecular Speculations on Global Abundance'' Edited by BC Crandall ({{ISBN|0-262-53137-2}}) offers interesting ideas for MNT applications.\n\n * [http://www.foresight.org Foresight Institute]\n* [https://web.archive.org/web/20041021010619/http://wise-nano.org/w/Main_Page Main Page - Wise-Nano] A [[wiki]] for MNT\n* [http://foresight.org/stage2/mechsynthbib.html Dr. Freitas's bibliography on mechanosynthesis] [http://www.MolecularAssembler.com/Nanofactory/AnnBibDMS.htm updated here] (also includes related techniques based on [[scanning probe microscopy]])\n* [http://www.MoleculArassembler.com/ The Molecular Assembler website of Robert A. Freitas Jr.]\n* [http://www.nanotech-now.com/ Nanotechnology Now] Nanotechnology basics, news, and general information\n* [http://www.e-drexler.com/ Eric Drexler's personal website and digital archive]\n* [http://www.nano.gov National Nanotechnology Initiative]\n* [http://www.imm.org/ Institute for Molecular Manufacturing]\n* [https://web.archive.org/web/20080608224707/http://www.acceleratingfuture.com/michael/blog/?cat=6 Accelerating Future's MNT articles]\n\n{{Molecular nanotechnology footer}}\n{{emerging technologies|topics=yes|robotics=yes|manufacture=yes|materials=yes}}", "Molecular nanotechnology --- Introduction ---|Introduction": "While conventional chemistry uses inexact processes obtaining inexact results, and biology exploits inexact processes to obtain definitive results, molecular nanotechnology would employ original definitive processes to obtain definitive results. The desire in molecular nanotechnology would be to balance molecular reactions in positionally-controlled locations and orientations to obtain desired chemical reactions, and then to build systems by further assembling the products of these reactions.\n\nA roadmap for the development of MNT is an objective of a broadly based technology project led by [[Battelle Memorial Institute|Battelle]] (the manager of several U.S. National Laboratories) and the [[Foresight Institute]].<ref>{{cite web |url=http://www.foresight.org/cms/press_center/282 |title=Foresight Institute press release |publisher=Foresight.org |date=2008-01-29 |access-date=2010-09-05 |url-status=dead |archive-url=https://web.archive.org/web/20100923024525/http://foresight.org/cms/press_center/282 |archive-date=2010-09-23 }}</ref> The roadmap was originally scheduled for completion by late 2006, but was released in January 2008.<ref>{{cite web|last=Peterson |first=Christine |url=http://www.foresight.org/nanodot/?p=2478#more-2478 |title=Nanodot: Nanotechnology News and Discussion \u00bb Blog Archive \u00bb Nanotechnology Roadmap launch: Productive Nanosystems Conference, Oct 9-10 |publisher=Foresight.org |date=2007-05-08 |access-date=2010-09-05}}</ref> The Nanofactory Collaboration<ref name="autogenerated3">{{cite web|url=http://www.MolecularAssembler.com/Nanofactory |title=Nanofactory Collaboration |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> is a more focused ongoing effort involving 23 researchers from 10 organizations and 4 countries that is developing a practical research agenda<ref name="autogenerated2">{{cite web|url=http://www.MolecularAssembler.com/Nanofactory/Challenges.htm |title=Nanofactory Technical Challenges |publisher=Molecularassembler.com |access-date=2010-09-05}}</ref> specifically aimed at positionally-controlled diamond mechanosynthesis and diamondoid nanofactory development. In August 2005, a task force consisting of 50+ international experts from various fields was organized by the [http://www.crnano.org/ Center for Responsible Nanotechnology] to study the societal implications of molecular nanotechnology.<ref>{{cite web|url=http://www.crnano.org|title=Global Task Force on Implications and Policy |publisher=Crnano.org |access-date=2010-09-05}}</ref>"}},
{"article_title": "Microelectromechanical systems", "pageid": "19638", "revid": "1062482319", "timestamp": "2021-12-28T18:49:26Z", "history_paths": [["Microelectromechanical systems --- Introduction ---", "History"]], "categories": ["transducers", "mechanical engineering", "electrical engineering", "microtechnology", "microelectronic and microelectromechanical systems", "articles containing video clips"], "heading_tree": {"Microelectromechanical systems --- Introduction ---": {"History": {}, "Types": {}, "Materials for MEMS manufacturing": {"Silicon": {}, "Polymers": {}, "Metals": {}, "Ceramics": {}}, "MEMS basic processes": {"Deposition processes": {"Physical deposition": {}, "Chemical deposition": {}}, "Patterning": {}, "Lithography": {"Electron beam lithography": {}, "Ion beam lithography": {}, "Ion track technology": {}, "X-ray lithography": {}, "Diamond patterning": {}}, "Etching processes": {"Wet etching": {"Isotropic etching": {}, "Anisotropic etching": {}, "HF etching": {}, "Electrochemical etching": {}}, "Dry etching": {"Vapor etching": {"Xenon difluoride": {}}, "Plasma etching": {"Sputtering": {}, "Reactive ion etching (RIE)": {}}}}, "Die preparation": {}}, "MEMS manufacturing technologies": {"Bulk micromachining": {}, "Surface micromachining": {}, "Thermal oxidation": {}, "High aspect ratio (HAR) silicon micromachining": {}}, "Applications": {}, "Industry structure": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microelectromechanical systems --- Introduction ---|History": "MEMS technology has roots in the [[silicon revolution]], which can be traced back to two important silicon [[semiconductor]] inventions from 1959: the [[monolithic integrated circuit]] (IC) chip by [[Robert Noyce]] at [[Fairchild Semiconductor]], and the [[MOSFET]] (metal-oxide-semiconductor field-effect transistor, or MOS transistor) by [[Mohamed M. Atalla]] and [[Dawon Kahng]] at [[Bell Labs]]. [[MOSFET scaling]], the miniaturisation of MOSFETs on IC chips, led to the miniaturisation of [[electronics]] (as predicted by [[Moore's law]] and [[Dennard scaling]]). This laid the foundations for the miniaturisation of mechanical systems, with the development of micromachining technology based on silicon semiconductor technology, as engineers began realizing that silicon chips and MOSFETs could interact and communicate with the surroundings and process things such as [[chemicals]], [[motions]] and [[light]]. One of the first silicon [[pressure sensor]]s was isotropically micromachined by [[Honeywell]] in 1962.<ref>{{cite book |last1=Rai-Choudhury |first1=P. |title=MEMS and MOEMS Technology and Applications |date=2000 |publisher=[[SPIE Press]] |isbn=9780819437167 |pages=ix, 3 |url=https://books.google.com/books?id=v6KOTaI2DhAC&pg=PR9}}</ref>\n\nAn early example of a MEMS device is the resonant-gate transistor, an adaptation of the MOSFET, developed by [[Harvey C. Nathanson]] in 1965.<ref>{{cite journal|vauthors=Nathanson HC, Wickstrom RA|date=1965|title=A Resonant-Gate Silicon Surface Transistor with High-Q Band-Pass Properties|journal=[[Applied Physics Letters|Appl. Phys. Lett.]]|volume=7|issue=4|pages=84\u201386|doi=10.1063/1.1754323|bibcode=1965ApPhL...7...84N}}</ref> Another early example is the resonistor, an electromechanical monolithic [[resonator]] patented by Raymond J. Wilfinger between 1966 and 1971.<ref>{{Cite patent|country=US|number=3614677A|title=Electromechanical monolithic resonator|status=patent|pubdate=|gdate=Oct 1971|invent1=Wilfinger RJ|inventor1-first=|assign1=International Business Machines Corp|url=https://patents.google.com/patent/US3614677A/en}}</ref><ref>{{cite journal|vauthors=Wilfinger RJ, Bardell PH, Chhabra DS|date=1968|title=The Resonistor: A Frequency Selective Device Utilizing the Mechanical Resonance of a Silicon Substrate|journal=[[IBM Journal of Research and Development|IBM J. Res. Dev.]]|volume=12|issue=1|pages=113\u20138|doi=10.1147/rd.121.0113}}</ref> During the 1970s to early 1980s, a number of MOSFET [[microsensor]]s were developed for measuring physical, chemical, biological and environmental parameters.<ref name="Bergveld">{{cite journal |last1=Bergveld |first1=Piet |author1-link=Piet Bergveld |title=The impact of MOSFET-based sensors |journal=Sensors and Actuators |date=October 1985 |volume=8 |issue=2 |pages=109\u2013127 |doi=10.1016/0250-6874(85)87009-8 |bibcode=1985SeAc....8..109B |url=https://core.ac.uk/download/pdf/11473091.pdf |issn=0250-6874}}</ref>"}},
{"article_title": "Maya numerals", "pageid": "19823", "revid": "1048246805", "timestamp": "2021-10-05T00:38:13Z", "history_paths": [["Maya numerals --- Introduction ---", "Origins"]], "categories": ["maya science and technology", "numerals", "numeral systems", "maya script", "vigesimal numeral systems"], "heading_tree": {"Maya numerals --- Introduction ---": {"Addition and subtraction": {}, "Modified vigesimal system in the Maya calendar": {}, "Origins": {}, "Unicode": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Maya numerals --- Introduction ---|Origins": "Several Mesoamerican cultures used similar numerals and base-twenty systems and the [[Mesoamerican Long Count calendar]] requiring the use of zero as a place-holder. The earliest long count date (on [[Chiapa de Corzo Stela 2#Notable finds|Stela 2]] at Chiapa de Corzo, [[Chiapas]]) is from 36 BC.<ref>No long count date actually using the number 0 has been found before the 3rd century, but since the long count system would make no sense without some placeholder, and since Mesoamerican glyphs do not typically leave empty spaces, these earlier dates are taken as indirect evidence that the concept of 0 already existed at the time.</ref>\n\nSince the eight earliest Long Count dates appear outside the Maya homeland,<ref>{{cite book|title=The Olmecs: America's First Civilization|last=Diehl|first=Richard|publisher=Thames & Hudson|year=2004|isbn=0-500-02119-8|location=London|page=[https://archive.org/details/olmecsamericasfi0000dieh/page/186 186]|oclc=56746987|author-link=Richard Diehl|url=https://archive.org/details/olmecsamericasfi0000dieh/page/186}}</ref> it is assumed that the use of zero and the Long Count calendar predated the Maya, and was possibly the invention of the [[Olmec]]. Indeed, many of the earliest Long Count dates were found within the Olmec heartland. However, the Olmec civilization had come to an end by the 4th century BC, several centuries before the earliest known Long Count dates\u2014which suggests that zero was ''not'' an Olmec discovery."}},
{"article_title": "Motorcycle", "pageid": "19876", "revid": "1062925889", "timestamp": "2021-12-31T06:02:56Z", "history_paths": [["Motorcycle --- Introduction ---", "History"]], "categories": ["motorcycle technology", "motorcycles", "motorcycling", "wheeled vehicles"], "heading_tree": {"Motorcycle --- Introduction ---": {"Types": {}, "History": {"Experimentation and invention": {"Summary of early inventions": {}}, "First motorcycle companies": {}, "First World War": {}, "Postwar": {}, "Today": {}}, "Technical aspects": {"Construction": {}, "Fuel economy": {"Electric motorcycles": {}}, "Reliability": {}, "Dynamics": {}, "Accessories": {}}, "Records": {}, "Safety": {}, "Motorcycle rider postures": {}, "Legal definitions and restrictions": {}, "Environmental impact": {"United States emissions limits": {}, "Europe": {}}, "See also": {}, "Citations": {}, "General references": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Motorcycle --- Introduction ---|History": "{{Main|History of the motorcycle}}\n\n [[File:Daimler-1-motorcycle-1.jpg|thumb|Replica of the Daimler-Maybach ''Reitwagen'']]\nThe first [[internal combustion engine|internal combustion]], [[petroleum]] fueled motorcycle was the [[Daimler Reitwagen|Daimler ''Reitwagen'']]. It was designed and built by the German inventors [[Gottlieb Daimler]] and [[Wilhelm Maybach]] in [[Bad Cannstatt]], Germany, in 1885.<ref name="ThePast1800s">{{cite web |title=The Past \u2013 1800s: First motorcycle |work=The History and Future of Motorcycles and motorcycling \u2013 From 1885 to the Future, Total Motorcycle Website |url=http://www.totalmotorcycle.com/future.htm#1800s |access-date=28 June 2007}}</ref> This vehicle was unlike either the [[safety bicycle]]s or the [[Boneshaker (bicycle)|boneshaker]] bicycles of the era in that it had zero degrees of [[Bicycle and motorcycle geometry#Steering axis angle|steering axis angle]] and no [[Bicycle and motorcycle geometry#Fork offset|fork offset]], and thus did not use the principles of [[bicycle and motorcycle dynamics]] developed nearly 70 years earlier. Instead, it relied on two outrigger wheels to remain upright while turning.{{sfn|Lienhard |2005|pp=120-121}}\n\nThe inventors called their invention the ''Reitwagen'' ("riding car"). It was designed as an expedient testbed for their new engine, rather than a true prototype vehicle.{{sfn|Setright |1979}}{{sfn|Falco|1999}}\n\n[[File:Butler's Patent Velocycle.jpg|thumb|Butler's Patent Velocycle]]\nThe first commercial design for a self-propelled cycle was a three-wheel design called the Butler Petrol Cycle, conceived of [[Edward Butler (inventor)|Edward Butler]] in [[England]] in 1884.<ref>{{cite encyclopedia|url=http://www.britannica.com/EBchecked/topic/394358/motorcycle|title=motorcycle (vehicle)|encyclopedia=Encyclop\u00e6dia Britannica}}</ref> He exhibited his plans for the vehicle at the [[Stanley Cycle Show]] in London in 1884. The vehicle was built by the [[Merryweather & Sons|Merryweather Fire Engine]] company in [[Greenwich, England|Greenwich]], in 1888.{{sfn|Georgano|2002|p=22}}\n\nThe Butler Petrol Cycle was a three-wheeled vehicle, with the rear wheel directly driven by a {{cvt|5/8|hp}}, {{cvt|40|cc}} displacement, {{cvt|2 + 1/4|\u00d7|5|in}} bore \u00d7 stroke, [[Flat twin engine|flat twin]] [[four-stroke engine]] (with [[magneto ignition]] replaced by coil and battery) equipped with [[rotary valves]] and a float-fed [[carburettor]] (five years before [[Wilhelm Maybach|Maybach]]) and [[Ackermann steering geometry|Ackermann steering]], all of which were state of the art at the time. Starting was by compressed air. The engine was liquid-cooled, with a [[radiator]] over the rear driving wheel. Speed was controlled by means of a [[throttle]] valve lever. No braking system was fitted; the vehicle was stopped by raising and lowering the rear driving wheel using a foot-operated lever; the weight of the machine was then borne by two small castor wheels. The driver was seated between the front wheels. It wasn't, however, a success, as Butler failed to find sufficient financial backing.{{sfn|Georgano|2002|pp=20-22}}\n\nMany authorities have excluded [[steam engine|steam powered]], [[electric motorcycles]] or diesel-powered two-wheelers from the definition of a 'motorcycle', and credit the Daimler ''Reitwagen'' as the world's first motorcycle.<ref name=OED>{{Cite book |title=Oxford English Dictionary Online |publisher=Oxford University Press |date=March 2009 |chapter=motorcycle, n. |quote= 1. A two-wheeled motor-driven road vehicle, resembling a bicycle but powered by an internal-combustion engine; (now) spec. one with an engine capacity, top speed, or weight greater than that of a moped.}}</ref><ref name=":0">{{Cite news |last=Long |first=Tony |date=30 August 2007 |title=Aug. 30, 1885: Daimler Gives World First 'True' Motorcycle |url=https://www.wired.com/2011/08/0830daimler-first-true-motorcycle/ |magazine=[[Wired (magazine)|Wired]] |issn=1059-1028 }}</ref>{{sfn|Kresnak|2008}} Given the rapid rise in use of electric motorcycles worldwide,<ref name=MotorBikeWriter.com>{{Cite web |url=http://motorbikewriter.com/electric-bikes-drive-global-sales/|title=Electric Bikes Drive Global Sales |date=24 December 2014 | access-date= 5 March 2015 }}</ref> defining only internal-combustion powered two-wheelers as 'motorcycles' is increasingly problematic. The first (petroleum fueled) internal-combustion motorcycles, like the German ''Reitwagen'', were, however, also the first practical motorcycles.<ref name=":0" /><ref>{{Cite journal|last=Barnum|first=Merritt H.|date=August 1963|title=New Image in Motorcycling|journal=American Motorcyclist|volume=17|pages=5|issn=0277-9358}}</ref><ref>{{Cite book|last=Wineland|first=Lynn|title=The Complete Book of Motorcycling|publisher=Petersen Publishing Company|year=1964|pages=7|asin=B0007E0SN8}}</ref>\n\nIf a two-wheeled vehicle with steam propulsion is considered a motorcycle, then the first motorcycles built seem to be the French [[Michaux-Perreaux steam velocipede]] which patent application was filled in December 1868,{{sfn|Setright |1979}}{{sfn|Falco|1999}} constructed around the same time as the American [[Roper steam velocipede]], built by [[Sylvester H. Roper]] [[Roxbury, Massachusetts]].{{sfn|Setright |1979}}{{sfn|Falco|1999}}\nwho demonstrated his machine at fairs and circuses in the eastern U.S. in 1867,<ref name="ThePast1800s"/> Roper built about 10 steam cars and cycles from the 1860s until his death in 1896.{{sfn|Kresnak|2008}}\n\n {| class="wikitable"\n|-\n! Year !! Vehicle !! Number of wheels !! Inventor !! Engine type !! Notes\n|-\n| 1867\u20131868 ||  [[Michaux-Perreaux steam velocipede]] || 2 || Pierre Michaux<br>Louis-Guillaume Perreaux || Steam || \n*One made\n|-\n| 1867\u20131868 || [[Roper steam velocipede]] || 2 || Sylvester Roper || Steam || \n*One made\n|-\n| 1885 || [[Daimler Reitwagen]] || 2 (plus 2 outriggers) || Gottlieb Daimler<br>Wilhelm Maybach || Petroleum internal-combustion || \n*One made\n|-\n| 1887 || [[Edward Butler (inventor)|Butler Petrol Cycle]] || 3 (plus 2 castors)|| Edward Butler || Petroleum internal-combustion ||\n|-\n| 1894 || [[Hildebrand & Wolfm\u00fcller]] || 2 || Heinrich Hildebrand<br>Wilhelm Hildebrand<br>Alois Wolfm\u00fcller || Petroleum internal-combustion || \n*Modern configuration\n*First mass-produced motorcycle\n*First machine to be called "motorcycle"\n|}\n\n [[File:1894 Hildebrand & Wolfm\u00fcller diagram.png|thumb|left|Diagram of 1894 Hildebrand & Wolfm\u00fcller]]\nIn 1894, [[Hildebrand & Wolfm\u00fcller]] became the first series production motorcycle, and the first to be called a motorcycle ({{lang-de|Motorrad}}).{{sfn|Setright |1979}}{{sfn|Falco|1999}}{{sfn|Kresnak|2008}}<ref name="Brief History of the Marque: Hildebrand & Wolfmuller">{{cite web |title=Brief History of the Marque: Hildebrand & Wolfmuller |work=Hildebrand & Wolfmuller Motorad, European Motorcycle Universe |url=http://www.cybermotorcycle.com/euro/brands/hildebrand_wolfmuller.htm |access-date=28 June 2007}}</ref> [[Excelsior Motor Company]], originally a bicycle manufacturing company based in [[Coventry]], [[England]], began production of their first motorcycle model in 1896. \n\nThe first production motorcycle in the US was the Orient-Aster, built by [[Metz Company|Charles Metz]] in 1898 at his factory in [[Waltham, Massachusetts]].\n\nIn the early period of motorcycle history, many producers of [[bicycle]]s adapted their designs to accommodate the new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers increased. Many of the nineteenth-century inventors who worked on early motorcycles often moved on to other inventions. Daimler and Roper, for example, both went on to develop automobiles.\n\n[[File:1902 Orient motocycle.jpg|thumb|1902 Orient motocycle]]\nAt the end of the 19th century the first major mass-production firms were set up. In 1898, [[Triumph Engineering|Triumph Motorcycles]] in England began producing motorbikes, and by 1903 it was producing over 500 bikes. Other British firms were [[Royal Enfield]], [[Norton Motorcycle Company|Norton]], [[Douglas (motorcycles)|Douglas Motorcycles]] and [[Birmingham Small Arms Company]] who began motorbike production in 1899, 1902, 1907 and 1910, respectively.<ref>{{Cite web|url=https://www.bikes4sale.in/wp/756/history-of-motorbikes/|title=History of Motorbikes|website=Bikes4Sale}}</ref> [[Indian (motorcycle)|Indian]] began production in 1901 and [[Harley-Davidson]] was established two years later. By the outbreak of World War I, the largest motorcycle manufacturer in the world was Indian,{{sfn|Walker|2006|p=66}}<ref>{{Cite book |publisher=The AMA Motorcycle Hall of Fame Museum |title=George Hendee |url=http://www.motorcyclemuseum.org/halloffame/detail.aspx?RacerID=68&lpos=-410px&letter=H&txtFname=&rblFname=S&txtLname=&rblLname=S&discipline=0 |access-date=8 August 2009 }}</ref>\nproducing over 20,000 bikes per year.<ref>{{Cite news |last=Youngblood |first=Ed |title=The Rise and Fall |periodical=American Motorcyclist |date=June 2001 |url=https://books.google.com/books?id=FPsDAAAAMBAJ&q=20,000&pg=PA30 |volume= 55 |issue=6 |publisher=American Motorcyclist Assoc}}</ref>\n\n [[File:Triumph 1922 H 1.jpg|thumb|[[Triumph Engineering|Triumph Motorcycles]] [[Triumph Type H|Model H]], mass-produced for the war effort and notable for its reliability]]\n\nDuring the First World War, motorbike production was greatly ramped up for the war effort to supply effective communications with front line troops. Messengers on horses were replaced with [[despatch rider]]s on motorcycles carrying messages, performing reconnaissance and acting as a military police. American company Harley-Davidson was devoting over 50% of its factory output toward military contract by the end of the war. The British company Triumph Motorcycles sold more than 30,000 of its [[Triumph Type H]] model to [[Triple Entente|allied forces]] during the war. With the rear wheel driven by a belt, the Model H was fitted with a {{Convert|499|cc|abbr=on}} air-cooled [[four-stroke]] single-cylinder engine. It was also the first Triumph without [[Bicycle pedal|pedals]].<ref>{{cite web |url=http://www.triumph1.com/triumph_history.htm|title=Triumph history |access-date=20 May 2009 |archive-url=https://web.archive.org/web/20080908002718/http://www.triumph1.com/triumph_history.htm |archive-date=8 September 2008 }}</ref>{{Better source|date=October 2014}}\n\nThe Model H in particular, is regarded by many as having been the first "modern motorcycle".<ref>{{cite web|url=http://www.motorcycle-usa.com/689/2598/Motorcycle-Article/Triumph-Motorcycle-History.aspx|title=Triumph Motorcycle History|access-date=18 November 2013|archive-url=https://web.archive.org/web/20150321013937/http://www.motorcycle-usa.com/689/2598/Motorcycle-Article/Triumph-Motorcycle-History.aspx|archive-date=21 March 2015|url-status=dead}}</ref> Introduced in 1915 it had a 550 cc side-valve four-stroke engine with a three-speed gearbox and belt transmission. It was so popular with its users that it was nicknamed the "Trusty Triumph".<ref>{{cite web|title=Triumph Motorcycles timeline|url=http://www.ianchadwick.com/motorcycles/triumph/time01.html |first=Ian |last=Chadwick}}</ref>\n\n [[File:Male Motorcycle rider posing with a Rudge racing bike, No. 45.jpg|thumb|Motorcycle rider on his [[Rudge-Whitworth]] motorbike, Australia, ca. 1935]]\nBy 1920, Harley-Davidson was the largest manufacturer,<ref>{{Cite web|url=https://pcmotors.com/harley.html|title=History of Harley-Davidson Motor Company|website=pcmotors.com}}</ref> with their motorcycles being sold by dealers in 67 countries.<ref>{{Cite news |title=HOG WILD; U of T professor Brendan Calder is one of the legions of baby boomers who have helped to ensure the success of the Harley-Davidson brand name, not to mention its bottom line.|first=Sharda |last=Prashad |periodical=Toronto Star |location=Toronto, Ont.|date=16 April 2006 |page=A.16 |url=https://pqasb.pqarchiver.com/thestar/doc/438968474.html?FMT=ABS&FMTS=ABS:FT&type=current&date=&author=&pub=&edition=&startpage=&desc=}}</ref><ref>{{Cite news |title=Harley-Davidson at 100 |first=Jeremy |last=Cato |periodical=Vancouver Sun|location=Vancouver, B.C. |date=8 August 2003 |page=E.1.Fro }}</ref>\n\nAmongst many British motorcycle manufacturers, Chater-Lea with its twin-cylinder models followed by its large singles in the 1920s stood out. Initially, using converted a Woodmann-designed ohv Blackburne engine it became the first 350 cc to exceed 100 mph (160 km/h), recording 100.81 mph (162.24 km/h) over the flying kilometre during April 1924.[7] Later, Chater-Lea set a world record for the flying kilometre for 350 cc and 500 cc motorcycles at 102.9 mph (165.6 km/h) for the firm. Chater-Lea produced variants of these world-beating sports models and became popular among racers at the Isle of Man TT. Today, the firm is probably best remembered for its long-term contract to manufacture and supply AA Patrol motorcycles and sidecars.{{citation needed|date=November 2019}}\n\nBy the late 1920s or early 1930s, [[DKW]] in Germany took over as the largest manufacturer.<ref>{{cite web |last=Vance |first=Bill |url=http://www.autos.ca/classic-cars/motoring-memories-dkw-auto-union-1928-1966/ |work=Canadian Driver |title=Motoring Memories: DKW/Auto Union, 1928\u20131966 |date=24 April 2009 }}</ref>{{sfn|de Cet |2002|p=128}}{{sfn|Walker|1999|p=61}}\n\n[[File:ZweiRadMuseumNSU NSU-SportMax 1955.JPG|thumb|left|NSU Sportmax streamlined motorcycle, 250 cc class winner of the [[1955 Grand Prix motorcycle racing season|1955 Grand Prix season]]]]\n\nIn the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and the "dustbin fairing" held out the possibility of radical changes to motorcycle design. [[NSU Motorenwerke|NSU]] and [[Moto Guzzi]] were in the vanguard of this development, both producing very radical designs well ahead of their time.{{sfn|Willoughby |1982}}\nNSU produced the most advanced design, but after the deaths of four NSU riders in the 1954\u20131956 seasons, they abandoned further development and quit [[Grand Prix motorcycle racing]].<ref>{{cite web |url=http://www.motorsportmemorial.org/focus.php?db=ms&n=1418 |work= Motorsport Memorial |title= Rupert Hollaus |access-date=3 April 2008}}</ref>\n\nMoto Guzzi produced competitive race machines, and until the end of 1957 had a succession of victories.<ref>{{cite web |title=Moto Guzzi History |url=http://www.motoguzzi.com/us_EN/passion/History/ |website=Moto Guzzi |access-date=23 February 2019}}</ref> The following year, 1958, full enclosure fairings were banned from racing by the [[F\u00e9d\u00e9ration Internationale de Motocyclisme|FIM]] in the light of the safety concerns.\n\nFrom the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of [[German Democratic Republic|East German]] [[MZ Motorrad- und Zweiradwerk|MZs]] Walter Kaaden's engine work in the 1950s.<ref name="Motocross goes International, 1947 through 1965">{{cite web |title=Motocross goes International, 1947 through 1965 |first=Ed |last=Youngblood |work=The History of Motocross, Part Two, Motorcycle Hall of Fame Museum |url=http://www.motorcyclemuseum.org/exhibits/mx/history2.asp |access-date=29 June 2007 |url-status=dead |archive-url=https://web.archive.org/web/20071113185300/http://www.motorcyclemuseum.org/exhibits/mx/history2.asp |archive-date=13 November 2007}}</ref>\n{{clear-right}}\n\n [[File:Royal Enfield Bullet, Rewalsar 2010.jpg|thumb|[[Royal Enfield Bullet]]]]\nIn the 21st century, the motorcycle industry is mainly dominated by Indian and Japanese motorcycle companies. In addition to the large capacity motorcycles, there is a large market in smaller capacity (less than 300 cc) motorcycles, mostly concentrated in Asian and African countries and produced in China and India.{{cn|date=July 2021}} A Japanese example is the 1958 [[Honda Super Cub]], which went on to become the biggest selling vehicle of all time, with its 60 millionth unit produced in April 2008.<ref>{{cite magazine|url=https://www.wired.com/2008/05/honda-sells-its/ |title=Honda Sells Its 60 Millionth \u2013 Yes, Millionth \u2013 Super Cub |magazine=Autopia |publisher=Wired |date=23 May 2008 |access-date=28 January 2010 |last=Squatriglia |first=Chuck }}</ref>\nToday, this area is dominated by mostly [[:Category:Motorcycle manufacturers of India|Indian companies]] with [[Hero MotoCorp]] emerging as the world's largest manufacturer of two wheelers. Its [[Hero Honda Splendor|Splendor]] model has sold more than 8.5 million to date.<ref>{{cite web|title=Hero Honda splendor sells more than 8.5 million units |url=http://www.indiacar.net/news/n60044.htm |publisher=indiacar.net |access-date=10 August 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080221200612/http://www.indiacar.net/news/n60044.htm |archive-date=21 February 2008 }}</ref> Other major producers are [[Bajaj Auto|Bajaj]] and [[TVS Motors]].<ref>{{cite web |last=O'Malley Greenburg |first=Zack |url=https://www.forbes.com/2007/08/05/india-autos-cheapest-oped-cz_zog_0813indiaauto.html |title=World's Cheapest Car |magazine=[[Forbes]] |date=13 August 2007 |access-date=28 January 2010}}</ref>"}},
{"article_title": "Mimeograph", "pageid": "19935", "revid": "1057110494", "timestamp": "2021-11-25T14:42:27Z", "history_paths": [["Mimeograph --- Introduction ---", "Origins"]], "categories": ["obsolete technologies", "office equipment", "printing devices", "copying"], "heading_tree": {"Mimeograph --- Introduction ---": {"Origins": {"Papyrograph": {}, "Electric pen": {}, "Cyclostyle": {}}, "Mimeography process": {"Preparing stencils": {}, "Limitations": {}}, "Durability": {}, "Contemporary use": {}, "Uses and art": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Mimeograph --- Introduction ---|Origins": "Use of [[stencil]]s is an ancient art, but{{emdash}}through chemistry, papers, and presses{{emdash}}techniques advanced rapidly in the late nineteenth century:\n\n A description of the Papyrograph method of duplication was published by David Owen:<ref> David Owen (2008) [https://books.google.ca/books?id=QbFobeCexgsC&pg=PA42 Copies in Seconds], page 42, [[Simon & Schuster]], Google book preview</ref> \n\n<blockquote>A major beneficiary of the invention of synthetic dyes was a document reproduction technique known as stencil duplicating. Its earliest form was invented in 1874 by Eugenio de Zuccato, a young Italian studying law in London, who called his device the Papyrograph.  Zuccato\u2019s system involved writing on a sheet of varnished paper with caustic ink, which ate through the varnish and paper fibers, leaving holes where the writing had been. This sheet \u2013 which had now become a stencil \u2013 was placed on a blank sheet of paper, and ink rolled over it so that the ink oozed through the holes, creating a duplicate on the second sheet.</blockquote>\n\nThe process was commercialized<ref>1878: [https://books.google.ca/books?id=tuLgAAAAMAAJ&pg=PA390 Library Journal 3:390] Advertisement via Google Books</ref><ref>[http://www.officemuseum.com/copy_machines.htm Antique Copying Machines] from Office Museum</ref> and Zuccato applied for a patent in 1895 having stencils prepared by typewriting.<ref>Eugenic de Zuccato (1895) [http://www.google.com/patents/US548116 Patent US548116]  Improvement for stencils from typewriting</ref>\n\n {{Main|Electric pen}}\n\n[[Thomas Edison]] received US patent 180,857 for '''Autographic Printing''' on August 8, 1876.<ref>http://edison.rutgers.edu/patents/00180857.PDF</ref>  The patent covered the '''electric pen''', used for making the stencil, and the flatbed duplicating press. In 1880 Edison obtained a further patent, US 224,665: "Method of Preparing Autographic Stencils for Printing," which covered the making of stencils using a file plate, a grooved metal plate on which the stencil was placed which perforated the stencil when written on with a blunt metal stylus.<ref>http://edison.rutgers.edu/patents/00224665.PDF</ref>\n\nThe word '''mimeograph''' was first used by [[Albert Blake Dick]]<ref>http://edison.rutgers.edu/NamesSearch/SingleDoc.php3?DocId=CA035A</ref> when he licensed Edison's patents in 1887.<ref>http://edison.rutgers.edu/NamesSearch/SingleDoc.php3?DocId=LB024149</ref>\n\nDick received [[Trademark]] Registration no. 0356815 for the term "Mimeograph" in the US Patent Office. It is currently listed as a dead entry, but shows the [[A.B. Dick Company]] of [[Chicago]] as the owner of the name.\n\nOver time, the term became generic and is now an example of a [[genericized trademark]].<ref>{{cite web|url=http://www.bartleby.com/61/68/M0306800.html|archive-url=https://web.archive.org/web/20080908113755/http://www.bartleby.com/61/68/M0306800.html|title=mimeograph. The American Heritage\u00ae Dictionary of the English Language: Fourth Edition. 2000.|archive-date=8 September 2008}}</ref> ("Roneograph," also "Roneo machine," was another trademark used for mimeograph machines, the name being a contraction of Rotary Neostyle.)\n\n {{Main|Cyclostyle (copier)}}\n \nIn 1891, [[David Gestetner]] patented his '''Automatic Cyclostyle'''.  This was one of the first rotary machines that retained the flatbed, which passed back and forth under inked rollers.  This invention provided for more automated, faster reproductions since the pages were produced and moved by rollers instead of pressing one single sheet at a time.\n\nBy 1900, two primary types of mimeographs had come into use: a single-drum machine and a dual-drum machine.  The single-drum machine used a single drum for ink transfer to the stencil, and the dual-drum machine used two drums and silk-screens to transfer the ink to the stencils. The single drum (example Roneo) machine could be easily used for multi-color work by changing the drum - each of which contained ink of a different color. This was spot color for mastheads. Colors could not be mixed.\n\nThe mimeograph became popular because it was much cheaper than traditional print - there was neither [[typesetting]] nor skilled labor involved. One individual with a [[typewriter]] and the necessary equipment became their own printing factory, allowing for greater circulation of printed material.\n\n<gallery widths="230" heights="170">\nFile:1889 Edison Mimeograph.jpg|Advertisement from 1889 for the Edison Mimeograph\nFile:Edison's* mimeograph box.jpg|A wooden Edison's mimeograph size 12"\nFile:Mimeograph, 1918.png|1918 illustration of a mimeograph machine\nFile:Mimeograph - The National Duplicator.JPG|Jackson & O'Sullivan's "The National" Duplicator. Produced in Brisbane, Queensland during WWII.\nFile:Resistance mimeograph machines.JPG|Mimeograph machines used by the [[Belgian resistance]] during World War II to produce underground newspapers and pamphlets\n</gallery>"}},
{"article_title": "Maser", "pageid": "19957", "revid": "1049422904", "timestamp": "2021-10-11T19:07:07Z", "history_paths": [["Maser --- Introduction ---", "History"]], "categories": ["american inventions", "laser types", "microwave technology", "optical devices", "emerging technologies"], "heading_tree": {"Maser --- Introduction ---": {"History": {}, "Technology": {"Some common types": {}, "21st-century developments": {}}, "Uses": {"Hydrogen maser": {}}, "Astrophysical masers": {}, "Terminology": {}, "In popular culture": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Maser --- Introduction ---|History": "The theoretical principles governing the operation of a maser were first described by [[Joseph Weber]] of the [[University of Maryland, College Park]] at the Electron Tube Research Conference in June 1952 in [[Ottawa]],<ref>[https://www.aip.org/history-programs/niels-bohr-library/oral-histories/4941 American Institute of Physics Oral History Interview with Weber]</ref> with a summary published in the June 1953 Transactions of the Institute of Radio Engineers Professional Group on Electron Devices,<ref>{{cite book |date=2004 |title=The History of the Laser |author=Mario Bertolotti |publisher=CRC Press |page=180|isbn=978-1420033403}}</ref> and simultaneously by [[Nikolay Basov]] and [[Alexander Prokhorov]] from [[Lebedev Physical Institute|Lebedev Institute of Physics]] at an ''All-Union Conference on Radio-Spectroscopy'' held by the [[USSR Academy of Sciences]] in May 1952, subsequently published in October 1954.\n\nIndependently, [[Charles H. Townes|Charles Hard Townes]], [[James P. Gordon]], and H. J. Zeiger built the first ammonia maser at [[Columbia University]] in 1953. This device used stimulated emission in a stream of energized [[ammonia]] molecules to produce amplification of microwaves at a frequency of about 24.0 [[hertz|gigahertz]].<ref>{{cite journal|last1=Gordon|first1=J. P.|last2=Zeiger|first2=H. J.|last3=Townes|first3=C. H.|title=The Maser\u2014New Type of Microwave Amplifier, Frequency Standard, and Spectrometer|journal=Phys. Rev.|date=1955|volume=99|issue=4|page=1264|bibcode=1955PhRv...99.1264G|doi=10.1103/PhysRev.99.1264|doi-access=free}}</ref> Townes later worked with [[Arthur Leonard Schawlow|Arthur L. Schawlow]] to describe the principle of the ''optical maser'', or ''laser'',<ref>{{cite journal |last1=Schawlow |first1=A.L. |last2=Townes |first2=C.H. |title=Infrared and Optical Masers |journal=Physical Review |date=15 December 1958 |volume=112 |issue=6 |pages=1940\u20131949 |doi=10.1103/PhysRev.112.1940 |doi-access=free |bibcode=1958PhRv..112.1940S }}</ref> of which [[Theodore Harold Maiman|Theodore H. Maiman]] created the first working model in 1960.\n\nFor their research in the field of stimulated emission, Townes, Basov and Prokhorov were awarded the [[Nobel Prize in Physics]] in 1964.<ref>{{Cite web|title=The Nobel Prize in Physics 1964|url=https://www.nobelprize.org/prizes/physics/1964/summary/|access-date=2020-08-27|website=NobelPrize.org|language=en-US}}</ref>"}},
{"article_title": "Microwave", "pageid": "20097", "revid": "1062124842", "timestamp": "2021-12-26T12:50:11Z", "history_paths": [["Microwave --- Introduction ---", "History"]], "categories": ["microwave technology", "electromagnetic spectrum", "radio technology"], "heading_tree": {"Microwave --- Introduction ---": {"Electromagnetic spectrum": {}, "Propagation": {"Troposcatter": {}}, "Antennas": {}, "Design and analysis": {}, "Microwave sources": {}, "Microwave uses": {"Communication": {}, "Navigation": {}, "Radar": {}, "Radio astronomy": {}, "Heating and power application": {}, "Spectroscopy": {}}, "Microwave frequency bands": {}, "Microwave frequency measurement": {}, "Effects on health {{anchor|Health effects}}": {}, "History": {"Hertzian optics": {}, "First microwave communication experiments": {}, "Radar": {}, "Post World War 2": {}, "Solid state microwave devices": {}, "Microwave integrated circuits": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microwave --- Introduction ---|History": "Microwaves were first generated in the 1890s in some of the earliest [[radio]] experiments by physicists who thought of them as a form of "invisible light".<ref name="Hong1">{{cite book\n | last1  = Hong\n | first1 = Sungook\n | title  = Wireless: From Marconi's Black-box to the Audion\n | publisher = MIT Press\n | date   = 2001\n | pages  = 5\u20139, 22\n | url    = https://archive.org/stream/WirelessFromMarconisBlack-boxToTheAudion/Hong_Sungook_Wireless_From_Marconis_Black-Box_to_the_Audion#page/n23/mode/2up\n | isbn   = 978-0262082983\n }}</ref>   [[James Clerk Maxwell]] in his 1873 theory of [[electromagnetism]], now called [[Maxwell's equations]], had predicted that a coupled [[electric field]] and [[magnetic field]] could travel through space as an [[electromagnetic wave]], and proposed that light consisted of electromagnetic waves of short wavelength.  In 1888, German physicist [[Heinrich Hertz]] was the first to demonstrate the existence of [[radio wave]]s using a primitive [[spark gap transmitter|spark gap radio transmitter]].<ref name="Roer">{{cite book\n | last1  = Roer\n | first1 = T.G.\n | title  = Microwave Electronic Devices\n | publisher = Springer Science and Business Media\n | date   = 2012\n | pages  = 1\u201312\n | url    = https://books.google.com/books?id=deDvBwAAQBAJ&pg=PA1\n | isbn   = 978-1461525004\n }}</ref>  Hertz and the other early radio researchers were interested in exploring the similarities between radio waves and light waves, to test Maxwell's theory.  They concentrated on producing short wavelength radio waves in the [[ultrahigh frequency|UHF]] and microwave ranges, with which they could duplicate classic [[optics]] experiments in their laboratories, using [[quasioptics|quasioptical]] components such as [[prism]]s and [[lens (optics)|lens]]es made of [[paraffin wax|paraffin]], [[sulfur]] and [[pitch (resin)|pitch]] and wire [[diffraction grating]]s, to refract and diffract radio waves like light rays.<ref name="Sarkar1">{{cite book\n | last1  = Sarkar\n | first1 = T. K.\n | last2  = Mailloux\n | first2 = Robert\n | last3  = Oliner\n | first3 = Arthur A.\n | title  = History of Wireless\n | publisher = John Wiley and Sons\n | date   = 2006\n | pages  = 474\u2013486\n | url    = https://archive.org/stream/HistoryOfWireless#page/n496/mode/2up\n | isbn   = 978-0471783015\n }}</ref>  Hertz produced waves up to 450 MHz; his directional 450 MHz transmitter consisted of a 26 cm brass rod [[dipole antenna]] with a spark gap between the ends, suspended at the focal line of a [[parabolic antenna]] made of a curved zinc sheet, powered by high voltage pulses from an [[induction coil]].<ref name="Roer" />  His historic experiments demonstrated that radio waves like light exhibited [[refraction]], [[diffraction]], [[polarization (waves)|polarization]], [[interference (wave motion)|interference]] and [[standing wave]]s,<ref name="Sarkar1" /> proving that radio waves and light waves were both forms of Maxwell's [[electromagnetic wave]]s.\n\n<gallery mode=packed heights=150>\nImage:Hertz spark gap transmitter and parabolic antenna.png|[[Heinrich Hertz]]'s 450 MHz spark transmitter, 1888, consisting of 23 cm dipole and spark gap at focus of parabolic reflector\nImage:Microwave Apparatus - Jagadish Chandra Bose Museum - Bose Institute - Kolkata 2011-07-26 4051.JPG|[[Jagadish Chandra Bose]] in 1894 was the first person to produce [[millimeter wave]]s; his spark oscillator ''(in box, right)'' generated 60 GHz (5 mm) waves using 3 mm metal ball resonators.\nImage:Refraction of Hertzian waves by paraffin prism.png|Microwave spectroscopy experiment by [[John Ambrose Fleming]] in 1897 showing refraction of 1.4 GHz microwaves by paraffin prism, duplicating earlier experiments by Bose and Righi.\nImage:Oscillatore di Righi con riflettore parabolico - Museo scienza tecnologia Milano 08757 1.jpg|[[Augusto Righi]]'s 12 GHz spark oscillator and receiver, 1895\n</gallery>\n[[Image:Marconi parabolic xmtr and rcvr 1895.jpg|thumb|upright=1.2|1.2 GHz microwave spark transmitter ''(left)'' and [[coherer]] receiver ''(right)'' used by [[Guglielmo Marconi]] during his 1895 experiments had a range of {{convert|6.5|km|mi|abbr=on|sigfig=2}} ]]\n\nBeginning in 1894 Indian physicist [[Jagadish Chandra Bose]] performed the first experiments with microwaves.  He was the first person to produce [[millimeter wave]]s, generating frequencies up to 60 GHz (5 millimeter) using a 3 mm metal ball spark oscillator.<ref name="Emerson">{{cite web |url=http://www.tuc.nrao.edu/~demerson/bose/bose.html |title=The work of Jagdish Chandra Bose: 100 years of MM-wave research |publisher=National Radio Astronomy Observatory |date=February 1998 |author=Emerson, D.T.}}</ref><ref name="Sarkar1" />  Bose also invented [[waveguide (electromagnetism)|waveguide]], [[horn antenna]]s, and [[semiconductor]] [[crystal detector]]s for use in his experiments.  Independently in 1894, [[Oliver Lodge]] and [[Augusto Righi]] experimented with 1.5 and 12 GHz microwaves respectively, generated by small metal ball spark resonators.<ref name="Sarkar1" />   Russian physicist [[Pyotr Lebedev]] in 1895 generated 50 GHz millimeter waves.<ref name="Sarkar1" />   In 1897 [[Lord Rayleigh]] solved the mathematical [[boundary-value problem]] of electromagnetic waves propagating through conducting tubes and dielectric rods of arbitrary shape.<ref name="Packard" /><ref name="Rayleigh">{{cite journal\n  | last1  = Strutt\n  | first1 = William (Lord Rayleigh)\n  | title =  On the passage of electric waves through tubes, or the vibrations of dielectric cylinders\n  | journal = Philosophical Magazine\n  | volume = 43\n  | issue = 261\n  | pages = 125\u2013132\n  | date = February 1897\n  | doi = 10.1080/14786449708620969\n  | url = https://zenodo.org/record/1431225\n  }}</ref><ref name="Kizer">{{cite book\n | last1  = Kizer\n | first1 = George\n | title  = Digital Microwave Communication: Engineering Point-to-Point Microwave Systems\n | publisher = John Wiley and Sons\n | date   = 2013\n | pages  = 7\n | url    = https://books.google.com/books?id=JVhGmjQ8TyoC&q=southworth+bose+lodge+waveguide\n | isbn   = 978-1118636800\n }}</ref><ref name="Lee3">{{cite book\n | last1  = Lee\n | first1 = Thomas H.\n | title  = Planar Microwave Engineering: A Practical Guide to Theory, Measurement, and Circuits, Vol. 1\n | publisher = Cambridge University Press\n | date   = 2004\n | pages  = 18, 118\n | url    = https://books.google.com/books?id=uoj3IWFxbVYC&pg=PA18\n | isbn   = 978-0521835268\n }}</ref> which gave the modes and [[cutoff frequency]] of microwaves propagating through a [[waveguide (electromagnetism)|waveguide]].<ref name="Roer" />\n\nHowever, since microwaves were limited to [[line-of-sight propagation|line of sight]] paths, they could not communicate beyond the visual horizon, and the low power of the spark transmitters then in use limited their practical range to a few miles.  The subsequent development of radio communication after 1896 employed lower frequencies, which could travel beyond the horizon as [[ground wave]]s and by reflecting off the [[ionosphere]] as [[skywave]]s, and microwave frequencies were not further explored at this time.\n\n Practical use of microwave frequencies did not occur until the 1940s and 1950s due to a lack of adequate sources, since the [[triode]] [[vacuum tube]] (valve) [[electronic oscillator]] used in radio transmitters could not produce frequencies above a few hundred [[megahertz]] due to excessive electron transit time and interelectrode capacitance.<ref name="Roer" />   By the 1930s, the first low-power microwave vacuum tubes had been developed using new principles; the [[Barkhausen-Kurz tube]] and the [[split-anode magnetron]].<ref name="Roer" />  These could generate a few watts of power at frequencies up to a few gigahertz and were used in the first experiments in communication with microwaves.\n<gallery mode=packed heights=150>\nImage:English Channel microwave relay antennas 1931.jpg|Antennas of 1931 experimental 1.7 GHz microwave relay link across the English Channel.\nImage:Westinghouse experimental 700 MHz transmitter 1932.jpg|Experimental 700 MHz transmitter 1932 at Westinghouse labs transmits voice over a mile.\nImage:Southworth demonstrating waveguide.jpg|Southworth ''(at left)'' demonstrating waveguide at [[Institute of Radio Engineers|IRE]] meeting in 1938, showing 1.5 GHz microwaves passing through the 7.5 m flexible metal hose registering on a diode detector.\nImage:Wilmer Barrow & horn antenna 1938.jpg|The first modern horn antenna in 1938 with inventor [[Wilmer L. Barrow]]\n</gallery>\nIn 1931 an Anglo-French consortium headed by [[Andre C. Clavier]] demonstrated the first experimental [[microwave relay]] link,  across the [[English Channel]] {{convert|40|mi|km}} between [[Dover]], UK and [[Calais]], France.<ref name="EC">{{cite magazine\n  | title = Microwaves span the English Channel\n  | magazine = Short Wave Craft\n  | volume = 6\n  | issue = 5\n  | pages = 262, 310\n  | publisher = Popular Book Co\n  | location = New York\n  | date = September 1935\n  | url = http://www.americanradiohistory.com/Archive-Short-Wave-Television/30s/SW-TV-1935-09.pdf\n  | access-date = March 24, 2015}}</ref><ref name="Free">{{cite magazine\n  | last1  = Free\n  | first1 = E.E.\n  | title = Searchlight radio with the new 7 inch waves\n  | magazine = Radio News\n  | volume = 8\n  | issue = 2\n  | pages = 107\u2013109\n  | publisher = Radio Science Publications\n  | location = New York\n  | date = August 1931\n  | url = http://www.americanradiohistory.com/Archive-Radio-News/30s/Radio-News-1931-08-R.pdf\n  | access-date = March 24, 2015}}</ref>  The system transmitted telephony, telegraph and [[facsimile]] data over bidirectional 1.7 GHz beams with a power of one-half watt, produced by miniature [[Barkhausen-Kurz tube]]s at the focus of {{convert|10|ft|m|0|adj=on}} metal dishes.\n\nA word was needed to distinguish these new shorter wavelengths, which had previously been lumped into the "[[short wave]]" band, which meant all waves shorter than 200 meters.  The terms ''quasi-optical waves'' and ''ultrashort waves'' were used briefly, but did not catch on.   The first usage of the word ''micro-wave'' apparently occurred in 1931.<ref name="Free" /><ref name="Ayto">{{cite book\n | last1  = Ayto\n | first1 = John\n | title  = 20th century words\n | date   = 2002\n | pages  = 269\n | url    = https://books.google.com/books?id=p0h5AAAAIAAJ&q=%22When+trials+with+wavelengths+as+low+as+18+cm+were+made+known,+there+was+undisguised+surprise+that+the+problem+of+the+micro-wave+had+been+solved+so+soon.%22\n | isbn   = 978-7560028743\n }}</ref>\n\n The development of [[radar]], mainly in secrecy, before and during [[World War 2]], resulted in the technological advances which made microwaves practical.<ref name="Roer" />  Wavelengths in the centimeter range were required to give the small radar antennas which were compact enough to fit on aircraft a narrow enough [[beamwidth]] to localize enemy aircraft.  It was found that conventional [[transmission line]]s used to carry radio waves had excessive power losses at microwave frequencies, and [[George Southworth]] at [[Bell Labs]] and [[Wilmer Barrow]] at [[Massachusetts Institute of Technology|MIT]] independently invented [[waveguide (electromagnetism)|waveguide]] in 1936.<ref name="Packard">{{cite journal\n  | last1  = Packard\n  | first1 = Karle S.\n  | title = The Origin of Waveguides: A Case of Multiple Rediscovery\n  | journal = IEEE Transactions on Microwave Theory and Techniques\n  | volume = MTT-32\n  | issue = 9\n  | pages = 961\u2013969\n  | date = September 1984\n  | url = http://www.ieeeghn.org/wiki/images/8/86/MTT_Waveguide_History.pdf\n  | doi = 10.1109/tmtt.1984.1132809\n  | access-date = March 24, 2015|bibcode = 1984ITMTT..32..961P | citeseerx = 10.1.1.532.8921\n  }}</ref>  Barrow invented the [[horn antenna]] in 1938 as a means to efficiently radiate microwaves into or out of a waveguide.  In a microwave [[radio receiver|receiver]], a [[linear circuit|nonlinear]] component was needed that would act as a [[detector (radio)|detector]] and [[frequency mixer|mixer]] at these frequencies, as vacuum tubes had too much capacitance.   To fill this need researchers resurrected an obsolete technology, the [[point contact diode|point contact]] [[crystal detector]] (cat whisker detector) which was used as a [[demodulator]] in [[crystal radio]]s around the turn of the century before vacuum tube receivers.<ref name="Roer" /><ref name="Riordan">{{Cite book | last = Riordan | first = Michael |author2=Lillian Hoddeson | title = Crystal fire: the invention of the transistor and the birth of the information age | publisher = W. W. Norton & Company | year = 1988 | location = US | pages = 89\u201392 | url = https://books.google.com/books?id=SZ6wm5ZSUmsC&pg=PA89 | isbn = 978-0-393-31851-7 }}</ref>  The low capacitance of [[semiconductor junction]]s allowed them to function at microwave frequencies.  The first modern [[silicon]] and [[germanium]] [[diode]]s were developed as microwave detectors in the 1930s, and the principles of [[semiconductor physics]] learned during their development led to [[semiconductor electronics]] after the war.<ref name="Roer" />\n\n<gallery mode=packed heights=150>\nImage:R&B Magnetron.jpg|thumb|[[John Randall (physicist)|Randall]] and [[Harry Boot|Boot]]'s prototype cavity magnetron tube at the [[University of Birmingham]], 1940. In use the tube was installed between the poles of an electromagnet\nImage:Prototype klystron cutaway.jpg|First commercial klystron tube, by General Electric, 1940, sectioned to show internal construction\nImage:AI Mk. VIIIA radar in Bristol Beaufighter VIF CH16665.jpg|[[AI Mk. VIII radar|British Mk. VIII]], the first microwave air intercept radar, in nose of British fighter.  Microwave radar, powered by the new [[magnetron|magnetron tube]], significantly shortened World War 2. \nImage:US Army Signal Corps AN-TRC-1, 5, 6, & 8 microwave relay station 1945.jpg|Mobile US Army microwave relay station 1945 demonstrating relay systems using frequencies from 100 MHz to 4.9 GHz which could transmit up to 8 phone calls on a beam.\n</gallery>\n\nThe first powerful sources of microwaves were invented at the beginning of World War 2: the [[klystron]] tube by [[Russell and Sigurd Varian]] at [[Stanford University]] in 1937, and the [[cavity magnetron]] tube by [[John Randall (physicist)|John Randall]] and [[Harry Boot]] at Birmingham University, UK in 1940.<ref name="Roer" />  Ten centimeter (3 GHz) microwave radar was in use on British warplanes in late 1941 and proved to be a game changer.  Britain's 1940 decision to share its microwave technology with its US ally (the [[Tizard Mission]]) significantly shortened the war.  The [[MIT Radiation Laboratory]] established secretly at [[Massachusetts Institute of Technology]] in 1940 to research radar, produced much of the theoretical knowledge necessary to use microwaves.   The first microwave relay systems were developed by the Allied military near the end of the war and used for secure battlefield communication networks in the European theater.\n\n After World War 2, microwaves were rapidly exploited commercially.<ref name="Roer" />  Due to their high frequency they had a very large information-carrying capacity ([[bandwidth (signal processing)|bandwidth]]); a single microwave beam could carry tens of thousands of phone calls.  In the 1950s and 60s transcontinental [[microwave transmission|microwave relay]] networks were built in the US and Europe to exchange telephone calls between cities and distribute television programs.  In the new [[television broadcasting]] industry, from the 1940s microwave dishes were used to transmit [[backhaul (broadcasting)|backhaul]] video feeds from mobile [[production truck]]s back to the studio, allowing the first [[remote broadcast|remote TV broadcasts]].  The first [[communications satellite]]s were launched in the 1960s, which relayed telephone calls and television between widely separated points on Earth using microwave beams.  In 1964, [[Arno Penzias]] and [[Robert Woodrow Wilson]] while investigating noise in a satellite horn antenna at [[Bell Labs]], Holmdel, New Jersey discovered [[cosmic microwave background radiation]].\n{{multiple image\n| align = right\n| direction = horizontal\n| header =\n| image1 = Hogg horn antennas.jpg\n| caption1 = C-band [[horn antenna]]s at a telephone switching center in Seattle, belonging to AT&T's Long Lines microwave relay network built in the 1960s.\n| width1 = 149\n| image2 = NIKE AJAX Anti-Aircraft Missile Radar3.jpg\n| caption2 = Microwave lens antenna used in the radar for the 1954 [[Nike Ajax]] anti-aircraft missile\n| width2 = 270\n| image3 = NS Savannah microwave oven MD8.jpg\n| caption3 = The first commercial microwave oven, Amana's [[Radarange]], in kitchen of US aircraft carrier Savannah in 1961\n| width3 = 120\n}}\nMicrowave radar became the central technology used in [[air traffic control]], maritime [[navigation]], [[anti-aircraft defense]], [[ballistic missile]] detection, and later many other uses.  Radar and satellite communication motivated the development of modern microwave antennas; the [[parabolic antenna]] (the most common type),  [[cassegrain antenna]], [[lens antenna]], [[slot antenna]], and [[phased array]].\n\nThe ability of [[short wave]]s to quickly heat materials and cook food had been investigated in the 1930s by  I. F. Mouromtseff at Westinghouse, and at the [[1933 Chicago World's Fair]] demonstrated cooking meals with a 60 MHz radio transmitter.<ref name="SWC">{{cite journal| title = Cooking with Short Waves| journal = Short Wave Craft| volume = 4| issue = 7| page = 394| date = November 1933| url = http://www.americanradiohistory.com/Archive-Short-Wave-Television/30s/SW-TV-1933-11.pdf| access-date = 23 March 2015}}</ref>  In 1945 [[Percy Spencer]], an engineer working on radar at [[Raytheon]], noticed that microwave radiation from a magnetron oscillator melted a candy bar in his pocket.  He investigated cooking with microwaves and invented the [[microwave oven]], consisting of a magnetron feeding microwaves into a closed metal cavity containing food, which was patented by Raytheon on 8 October 1945.  Due to their expense microwave ovens were initially used in institutional kitchens, but by 1986 roughly 25% of households in the U.S. owned one.   Microwave heating became widely used as an industrial process in industries such as plastics fabrication, and as a medical therapy to kill cancer cells in [[hyperthermy|microwave hyperthermy]].\n\nThe [[traveling wave tube]] (TWT) developed in 1943 by [[Rudolph Kompfner]] and [[John R. Pierce|John Pierce]] provided a high-power tunable source of microwaves up to 50 GHz, and became the most widely used microwave tube (besides the ubiquitous magnetron used in microwave ovens).  The [[gyrotron]] tube family developed in Russia could produce megawatts of power up into [[millimeter wave]] frequencies and is used in industrial heating and [[plasma (physics)|plasma]] research, and to power [[particle accelerator]]s and nuclear [[fusion reactor]]s.\n\n {{multiple image\n| align = right\n| direction = horizontal\n| image1 = Ganna gjenerators M31102-1.jpg\n| caption1 = Microwave oscillator consisting of a [[Gunn diode]] inside a [[cavity resonator]], 1970s\n| width1 = 120\n| image2 = Radar Gun Electronics.jpg\n| caption2 = Modern [[radar speed gun]].  At the right end of the copper [[horn antenna]] is the [[Gunn diode]] ''(grey assembly)'' which generates the microwaves.\n| width2 = 180\n}}\nThe development of [[semiconductor electronics]] in the 1950s led to the first [[solid state electronics|solid state]] microwave devices which worked by a new principle; [[negative resistance]] (some of the prewar microwave tubes had also used negative resistance).<ref name="Roer" />  The [[electronic oscillator|feedback oscillator]] and [[two-port]] amplifiers which were used at lower frequencies became unstable at microwave frequencies, and [[negative resistance]] oscillators and amplifiers based on [[one-port]] devices like [[diode]]s worked better.\n\nThe [[tunnel diode]] invented in 1957 by Japanese physicist [[Leo Esaki]] could produce a few milliwatts of microwave power.  Its invention set off a search for better negative resistance semiconductor devices for use as microwave oscillators, resulting in the invention of the [[IMPATT diode]] in 1956 by [[W.T. Read]] and Ralph L. Johnston and the [[Gunn diode]] in 1962 by [[J. B. Gunn]].<ref name="Roer" />  Diodes are the most widely used microwave sources today.  \n\nTwo low-noise [[Solid-state electronics|solid state]] negative resistance microwave [[amplifier]]s were developed; the ruby [[maser]] invented in 1953 by [[Charles H. Townes]], [[James P. Gordon]], and [[H. J. Zeiger]], and the [[varactor]] [[parametric amplifier]] developed in 1956 by Marion Hines.<ref name="Roer" />  These were used for low noise microwave receivers in radio telescopes and [[satellite ground station]]s.  The maser led to the development of [[atomic clock]]s, which keep time using a precise microwave frequency emitted by atoms undergoing an [[electron transition]] between two energy levels.  Negative resistance amplifier circuits required the invention of new [[Reciprocity (electrical networks)|nonreciprocal]] waveguide components, such as [[circulator]]s,  [[isolator (microwave)|isolator]]s, and [[directional coupler]]s.  In 1969 Kurokawa derived mathematical conditions for stability in negative resistance circuits which formed the basis of microwave oscillator design.<ref name="Kurokawa">{{cite journal\n  | last = Kurokawa\n  | first = K.\n  | title = Some Basic Characteristics of Broadband Negative Resistance Oscillator Circuits\n  | journal = Bell System Tech. J.\n  | volume = 48\n  | issue = 6\n  | pages = 1937\u20131955\n  | date = July 1969\n  | url = https://archive.org/details/bstj48-6-1937\n  | doi = 10.1002/j.1538-7305.1969.tb01158.x\n  | access-date = December 8, 2012}}</ref>\n\n [[Image:LNB dissassembled.JPG|thumb|upright=0.7|[[ku band|k<sub>u</sub> band]] [[microstrip]] circuit used in [[satellite television]] dish.]]\nPrior to the 1970s microwave devices and circuits were bulky and expensive, so microwave frequencies were generally limited to the output stage of transmitters and the [[RF front end]] of receivers, and signals were [[heterodyning|heterodyned]] to a lower [[intermediate frequency]] for processing.  The period from the 1970s to the present has seen the development of tiny inexpensive active solid-state microwave components which can be mounted on circuit boards, allowing circuits to perform significant [[signal processing]] at microwave frequencies.  This has made possible [[satellite television]], [[cable television]], [[GPS]] devices, and modern wireless devices, such as [[smartphone]]s, [[Wi-Fi]], and [[Bluetooth]] which connect to networks using microwaves.\n\n[[Microstrip]], a type of [[transmission line]] usable at microwave frequencies, was invented with [[printed circuit]]s in the 1950s.<ref name="Roer" />  The ability to cheaply fabricate a wide range of shapes on [[printed circuit board]]s allowed microstrip versions of [[capacitor]]s, [[inductor]]s, [[Stub (electronics)|resonant stubs]], [[Power dividers and directional couplers|splitters]], [[directional coupler]]s, [[diplexer]]s, [[electronic filter|filters]] and antennas to be made, thus allowing compact microwave circuits to be constructed.<ref name="Roer" />\n\n[[Transistor]]s that operated at microwave frequencies were developed in the 1970s.  The semiconductor [[gallium arsenide]] (GaAs) has a much higher [[electron mobility]] than silicon,<ref name="Roer" /> so devices fabricated with this material can operate at 4 times the frequency of similar devices of silicon.  Beginning in the 1970s GaAs was used to make the first microwave transistors,<ref name="Roer" /> and it has dominated microwave semiconductors ever since.  MESFETs ([[metal-semiconductor field-effect transistor]]s), fast GaAs [[field effect transistor]]s using [[Schottky diode|Schottky junctions]] for the gate, were developed starting in 1968 and have reached cutoff frequencies of 100 GHz, and are now the most widely used active microwave devices.<ref name="Roer" />  Another family of transistors with a higher frequency limit is the HEMT ([[high electron mobility transistor]]), a [[field effect transistor]] made with two different semiconductors, AlGaAs and GaAs, using [[heterojunction]] technology, and the similar HBT ([[heterojunction bipolar transistor]]).<ref name="Roer" />\n\nGaAs can be made semi-insulating, allowing it to be used as a [[wafer (electronics)|substrate]] on which circuits containing [[passive component]]s, as well as transistors, can be fabricated by lithography.<ref name="Roer" /> By 1976 this led to the first [[integrated circuit]]s (ICs) which functioned at microwave frequencies, called [[monolithic microwave integrated circuit]]s (MMIC).<ref name="Roer" />  The word "monolithic" was added to distinguish these from microstrip PCB circuits, which were called "microwave integrated circuits" (MIC).   Since then silicon MMICs have also been developed.  Today MMICs have become the workhorses of both analog and digital high-frequency electronics, enabling the production of single-chip microwave receivers, broadband [[amplifier]]s, [[modem]]s, and [[microprocessor]]s."}},
{"article_title": "MIPS architecture", "pageid": "20170", "revid": "1060570810", "timestamp": "2021-12-16T09:42:02Z", "history_paths": [["MIPS architecture --- Introduction ---", "History"]], "categories": ["mips architecture", "advanced risc computing", "computer-related introductions in 1985", "instruction set architectures", "mips technologies"], "heading_tree": {"MIPS architecture --- Introduction ---": {"History": {}, "Design": {}, "Versions": {"MIPS I": {"Registers": {}, "Instruction formats": {}, "CPU instructions": {}}, "MIPS II": {}, "MIPS III": {}, "MIPS IV": {}, "MIPS V": {}, "MIPS32/MIPS64": {}, "microMIPS": {}}, "Application-specific extensions": {}, "Calling conventions": {}, "Uses": {}, "Simulators": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"MIPS architecture --- Introduction ---|History": "{{expand section|date=February 2020}}\n{{See also|MIPS Technologies}}\n\nThe first version of the MIPS architecture was designed by [[MIPS Computer Systems]] for its [[R2000 (microprocessor)|R2000]] microprocessor, the first MIPS implementation. Both MIPS and the R2000 were introduced together in 1985.{{citation needed|date=June 2016}} When MIPS II was introduced, ''MIPS'' was renamed ''MIPS I'' to distinguish it from the new version.<ref name=Sweetman1999/>{{rp|32}}\n\n[[MIPS Computer Systems]]' [[R6000]] microprocessor (1989) was the first MIPS II implementation.<ref name=Sweetman1999/>{{rp|8}} Designed for servers, the R6000 was fabricated and sold by [[Bipolar Integrated Technology]], but was a commercial failure. During the mid-1990s, many new 32-bit MIPS processors for [[embedded system]]s were MIPS II implementations because the introduction of the 64-bit MIPS III architecture in 1991 left MIPS II as the newest 32-bit MIPS architecture until MIPS32 was introduced in 1999.<ref name=Sweetman1999/>{{rp|19}}\n\n[[MIPS Computer Systems]]' [[R4000]] microprocessor (1991) was the first MIPS III implementation. It was designed for use in personal, workstation, and server computers. MIPS Computer Systems aggressively promoted the MIPS architecture and R4000, establishing the [[Advanced Computing Environment]] (ACE) consortium to advance its [[Advanced RISC Computing]] (ARC) standard, which aimed to establish MIPS as the dominant personal computing platform. ARC found little success in personal computers, but the R4000 (and the R4400 derivative) were widely used in workstation and server computers, especially by its largest user, [[Silicon Graphics]]. Other uses of the R4000 included high-end embedded systems and supercomputers. MIPS III was eventually implemented by a number of embedded microprocessors. [[Quantum Effect Design]]'s [[R4600]] (1993) and its derivatives was widely used in high-end embedded systems and low-end workstations and servers. MIPS Technologies' [[R4200]] (1994), was designed for embedded systems, laptop, and personal computers. A derivative, the R4300i, fabricated by [[NEC Electronics]], was used in the [[Nintendo 64]] game console. The Nintendo 64, along with the [[PlayStation (console)|PlayStation]], were among the highest volume users of MIPS architecture processors in the mid-1990s.\n\nThe first MIPS IV implementation was the MIPS Technologies [[R8000]] microprocessor chipset (1994). The design of the R8000 began at Silicon Graphics, Inc. and it was only used in high-end workstations and servers for scientific and technical applications where high performance on large floating-point workloads was important. Later implementations were the MIPS Technologies [[R10000]] (1996) and the Quantum Effect Devices [[R5000]] (1996) and [[RM7000]] (1998). The R10000, fabricated and sold by NEC Electronics and Toshiba, and its derivatives were used by NEC, Pyramid Technology, Silicon Graphics, and Tandem Computers (among others) in workstations, servers, and supercomputers. The R5000 and R7000 found use in high-end embedded systems, personal computers, and low-end workstations and servers. A derivative of the R5000 from Toshiba, the R5900, was used in Sony Computer Entertainment's [[Emotion Engine]], which powered its [[PlayStation 2]] game console.\n\nAnnounced on October 21, 1996, at the Microprocessor Forum 1996 alongside the [[MDMX|MIPS Digital Media Extensions]] (MDMX) extension, MIPS V was designed to improve the performance of 3D graphics transformations.<ref>{{cite web|url=http://infopad.eecs.berkeley.edu/CIC/otherpr/enhanced_mips.html|title=Silicon Graphics Introduces Enhanced MIPS Architecture to Lead the Interactive Digital Revolution|publisher=[[Silicon Graphics, Inc.]]|date=October 21, 1996|url-status=dead|archive-url=https://archive.today/20120710115823/http://infopad.eecs.berkeley.edu/CIC/otherpr/enhanced_mips.html|archive-date=July 10, 2012}}</ref> In the mid-1990s, a major use of non-embedded MIPS microprocessors were graphics workstations from Silicon Graphics. MIPS V was completed by the integer-only MDMX extension to provide a complete system for improving the performance of 3D graphics applications.<ref name="MPR:1996-11-18">{{cite journal|last=Gwennap|first=Linley|date=November 18, 1996|url=http://studies.ac.upc.edu/ETSETB/SEGPAR/microprocessors/mdmx%20(mpr).pdf|title=Digital, MIPS Add Multimedia Extensions|journal=[[Microprocessor Report]]|volume=10|issue=15|pages=24\u201328|url-status=live|archive-url=https://web.archive.org/web/20110720095552/http://studies.ac.upc.edu/ETSETB/SEGPAR/microprocessors/mdmx%20(mpr).pdf|archive-date=July 20, 2011}}</ref> MIPS V implementations were never introduced. On May 12, 1997, Silicon Graphics announced the H1 ("Beast") and H2 ("Capitan") microprocessors. The former was to have been the first MIPS V implementation, and was due to be introduced in the first half of 1999.<ref>{{cite press release |title=Silicon Graphics Previews New High-Performance MIPS Microprocessor Roadmap |date=May 12, 1997}}</ref> The H1 and H2 projects were later combined and eventually canceled in 1998. While there have not been any MIPS V implementations, MIPS64 Release 1 (1999) was based on MIPS V and retains all of its features as an optional Coprocessor 1 (FPU) feature called Paired-Single.\n\nWhen MIPS Technologies was spun-out of Silicon Graphics in 1998, it refocused on the embedded market. Through MIPS V, each successive version was a strict superset of the previous version, but this property was found to be a problem,{{citation needed|date=June 2016}} and the architecture definition was changed to define a 32-bit and a 64-bit architecture: MIPS32 and MIPS64. Both were introduced in 1999.<ref name="mips32-and-mips64">{{cite press release|url=http://www.thefreelibrary.com/MIPS+Technologies,+Inc.+Enhances+Architecture+to+Support+Growing+Need...-a054531136|title=MIPS Technologies, Inc. Enhances Architecture to Support Growing Need for IP Re-Use and Integration|date=May 3, 1999|publisher=[[Business Wire]]}}</ref> MIPS32 is based on MIPS II with some additional features from MIPS III, MIPS IV, and MIPS V; MIPS64 is based on MIPS V.<ref name="mips32-and-mips64"/> [[Nippon Electric Corporation|NEC]], [[Toshiba]] and [[SiByte]] (later acquired by [[Broadcom Corporation|Broadcom]]) each obtained licenses for MIPS64 as soon as it was announced. [[Philips]], [[LSI Corporation|LSI Logic]], [[Integrated Device Technology|IDT]], [[RMI Corporation|Raza Microelectronics, Inc.]], [[Cavium]], [[Loongson|Loongson Technology]] and [[Ingenic Semiconductor]] have since joined them. MIPS32/MIPS64 Release 5 was announced on December 6, 2012.<ref>{{cite press release|url=http://www.mips.com/news-events/newsroom/newsindex/index.dot?id=79069 |title=Latest Release of MIPS Architecture Includes Virtualization and SIMD Key Functionality for Enabling Next Generation of MIPS-Based Products|publisher=[[MIPS Technologies]]|date=December 6, 2012|archive-url=https://web.archive.org/web/20121213115846/http://www.mips.com/news-events/newsroom/newsindex/index.dot?id=79069|archive-date=December 13, 2012 }}</ref> Release 4 was skipped because the number four is perceived as [[Tetraphobia|unlucky]] in many Asian cultures.<ref>{{cite magazine|url=http://www.eetasia.com/ART_8800679179_480100_NT_439c939b.HTM|title=MIPS skips Release 4 amid bidding war|date=December 10, 2012|magazine=[[EE Times]]|url-status=live|archive-url=https://archive.today/20140417002825/http://www.eetasia.com/ART_8800679179_480100_NT_439c939b.HTM|archive-date=April 17, 2014}}</ref>\n\n{{anchor|Open}}In December 2018, Wave Computing, the new owner of the MIPS architecture, announced that MIPS ISA would be open-sourced in a program dubbed the MIPS Open initiative.<ref>{{cite web|url=https://wavecomp.ai/wave-computing-extends-ai-lead-by-targeting-edge-of-cloud-through-acquisition-of-mips|title=Wave Computing Extends AI Lead by Targeting Edge of Cloud Through Acquisition of MIPS|date=June 15, 2018}}</ref> The program was intended to open up access to the most recent versions of both the 32-bit and 64-bit designs making them available without any licensing or royalty fees as well as granting participants licenses to existing MIPS patents.<ref>{{cite web|url=https://wavecomp.ai/wave-computing-launches-the-mips-open-initiative|title=Wave Computing\u00ae Launches the MIPS Open Initiative To Accelerate Innovation for the Renowned MIPS\u00ae Architecture|date=December 17, 2018}}</ref><ref>{{cite web |title=MIPS Processor ISA To Be Open-Sourced In 2019 - Phoronix |url=https://www.phoronix.com/scan.php?page=news_item&px=MIPS-Open-Source-2019}}</ref><ref>{{Cite web |url=https://www.eetimes.com/document.asp?doc_id=1334087 |title=MIPS Goes Open Source |last=Yoshida |first=Junko |date=December 17, 2018 |website=EE Times }}</ref>\n\nIn March 2019, one version of the architecture was made available under a royalty-free license,<ref>{{cite web|url=https://www.eetimes.com/mips-r6-architecture-now-available-for-open-use/|title=MIPS R6 Architecture Now Available for Open Use|date=March 28, 2019}}</ref> but later that year the program was shut down again.<ref>{{cite web|url=https://www.hackster.io/news/wave-computing-closes-its-mips-open-initiative-with-immediate-effect-zero-warning-e88b0df9acd0|title=Wave Computing Closes Its MIPS Open Initiative with Immediate Effect, Zero Warning|date=November 15, 2019}}</ref>\n\nIn March 2021, Wave Computing announced that the development of the MIPS architecture has ceased. The company has joined the RISC-V foundation and future processor designs will be based on the RISC-V architecture.<ref>[https://www.eejournal.com/article/wait-what-mips-becomes-risc-v/ MIPS becomes RISC-V] March 8, 2021. Retrieved March 11, 2021.</ref><ref>[https://www.prnewswire.com/news-releases/wave-computing-and-mips-emerge-from-chapter-11-bankruptcy-301237051.html Wave Computing and MIPS emerge from chapter 11 bankruptcy] March 1, 2021. Retrieved March 11, 2021.</ref> In spite of this, some licensees such as Longsoon continue with new extension of MIPS-compatible ISAs on their own.<ref>{{cite news |last1=Shilov |first1=Anton |title=Loongson Rips MIPS: Uses Old Code for New CPUs |url=https://www.tomshardware.com/uk/news/loongson-continues-to-use-mips-code-for-loongarch-cpus |access-date=1 December 2021 |work=Tom's Hardware |date=25 August 2021 |language=en}}</ref>"}},
{"article_title": "Cavity magnetron", "pageid": "20861", "revid": "1061384286", "timestamp": "2021-12-21T11:09:57Z", "history_paths": [["Cavity magnetron --- Introduction ---", "History"]], "categories": ["science and technology during world war ii", "english inventions", "microwave technology", "radar", "vacuum tubes", "world war ii british electronics", "world war ii american electronics"], "heading_tree": {"Cavity magnetron --- Introduction ---": {"Construction and operation": {"Conventional tube design": {}, "Hull or single-anode magnetron": {}, "Split-anode magnetron": {}, "Cavity magnetron": {}}, "Common features": {}, "Applications": {"Radar": {}, "Heating": {}, "Lighting": {}}, "History": {}, "Health hazards": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cavity magnetron --- Introduction ---|History": "In 1910 [[Hans Gerdien]] (1877\u20131951) of the Siemens Corporation invented a magnetron.<ref>See:\n*  Gerdien, H., Deutsches Reichspatent 276,528 (12 January 1910).\n*  {{cite book|editor1-last=Banneitz|editor1-first=F.|title=Taschenbuch der drahtlosen Telegraphie und Telephonie|trans-title=Pocket book of wireless telegraphy and telephony|date=1927|publisher=Springer Verlag|location=Berlin, Germany|page=514 footnote|url=https://books.google.com/books?id=nNaRBwAAQBAJ&pg=PA514|language=de|isbn=9783642507892}}</ref><ref>{{cite book|last1=Goerth|first1=Joachim|title=International Conference on the Origins and Evolution of the Cavity Magnetron (CAVMAG 2010), Bournemouth, England, UK, 19\u201320 April 2010|date=2010|publisher=IEEE|location=Piscataway, New Jersey|pages=17\u201322|chapter=Early magnetron development especially in Germany}}</ref> In 1912, Swiss physicist [[Heinrich Greinacher]] was looking for new ways to calculate the [[electron mass]]. He settled on a system consisting of a diode with a cylindrical anode surrounding a rod-shaped cathode, placed in the middle of a magnet. The attempt to measure the electron mass failed because he was unable to achieve a good vacuum in the tube. However, as part of this work, Greinacher developed mathematical models of the motion of the electrons in the crossed magnetic and electric fields.<ref>{{cite journal|last1=Greinacher|first1=H.|title=\u00dcber eine Anordnung zur Bestimmung von e/m|journal=Verhandlungen der Deutschen Physikalischen Gesellschaft|date=1912|volume=14|pages=856\u201364|url=http://babel.hathitrust.org/cgi/pt?id=coo.31924056112091;view=1up;seq=878|trans-title=On an apparatus for the determination of e/m|language=de}}</ref><ref>{{cite web|url=http://www.radartutorial.eu/04.history/hi80.en.html|title=Radar Basics|first=Dipl.-Ing. (FH) Christian|last=Wolff|website=www.radartutorial.eu|access-date=5 May 2018|url-status=live|archive-url=https://web.archive.org/web/20171223044102/http://www.radartutorial.eu/04.history/hi80.en.html|archive-date=23 December 2017}}</ref>\n\nIn the US, [[Albert Hull]] put this work to use in an attempt to bypass [[Western Electric]]'s patents on the triode. Western Electric had gained control of this design by buying [[Lee De Forest]]'s patents on the control of current flow using electric fields via the "grid". Hull intended to use a variable magnetic field, instead of an electrostatic one, to control the flow of the electrons from the cathode to the anode. Working at [[General Electric]]'s Research Laboratories in [[Schenectady, New York]], Hull built tubes that provided switching through the control of the ratio of the magnetic and electric field strengths. He released several papers and patents on the concept in 1921.<ref>See:\n*  {{cite journal|last1=Hull|first1=Albert W.|title=The effect of a uniform magnetic field on the motion of electrons between coaxial cylinders|journal=Physical Review|date=1921|volume=18|issue=1|pages=31\u201357|url=https://books.google.com/books?id=OrYWAAAAYAAJ&pg=PA31|doi=10.1103/PhysRev.18.31|bibcode=1921PhRv...18...31H}}\n*  {{cite journal|last1=Hull|first1=Albert W.|title=The magnetron|journal=Journal of the American Institute of Electrical Engineers|date=September 1921|volume=40|issue=9|pages=715\u201323|url=https://babel.hathitrust.org/cgi/pt?id=njp.32101048908923;view=1up;seq=729|doi=10.1109/JoAIEE.1921.6594005|s2cid=51641488}}</ref>\n\nHull's magnetron was not originally intended to generate VHF (very-high-frequency) electromagnetic waves.  However, in 1924, Czech physicist August \u017d\u00e1\u010dek<ref>Biographical information about August \u017d\u00e1\u010dek: \n*  {{cite journal|last1=F\u00fcrth|first1=R. H.|title=Prof. August \u017d\u00e1\u010dek|journal=Nature|date=1962|volume=193|issue=4816|page=625|doi=10.1038/193625b0|bibcode=1962Natur.193..625F|doi-access=free}}\n*  {{cite journal|last1=(Anon.)|title=The 70th birthday of Prof. Dr. August \u017d\u00e1\u010dek|journal=Czechoslovak Journal of Physics|date=1956|volume=6|issue=2|pages=204\u201305|doi=10.1007/BF01699894|bibcode=1956CzJPh...6..204.|s2cid=189766320}}  Available on-line at:  [http://resources.metapress.com/pdf-preview.axd?code=h05r1105157t7x38&size=largest Metapress.com] {{webarchive|url=https://web.archive.org/web/20120312052512/http://resources.metapress.com/pdf-preview.axd?code=h05r1105157t7x38&size=largest |date=2012-03-12 }}.</ref> (1886\u20131961) and German physicist Erich Habann<ref>Biographical information about Erich Habann:  \n*  G\u00fcnter Nagel, "Pionier der Funktechnik.  Das Lebenswerk des Wissenschaftlers Erich Habann, der in Hessenwinkel lebte, ist heute fast vergessen" (Pioneer in Radio Technology.  The life's work of scientist Erich Habann, who lived in Hessenwinkel, is nearly forgotten today.), ''Bradenburger Bl\u00e4tter'' (supplement of the ''M\u00e4rkische Oderzeitung'', a daily newspaper of the city of Frankfurt in the state of Brandenburg, Germany), 15 December 2006, page 9.\n*  {{cite book|editor1-last=Karlsch|editor1-first=Rainer|editor2-last=Petermann|editor2-first=Heiko|title=F\u00fcr und Wider "Hitlers Bombe": Studien zur Atomforschung in Deutschland|trans-title=For and Against "Hitler's Bomb": Studies on atomic research in Germany|date=2007|publisher=Waxmann Publishing Co.|location=New York|page=251 footnote|language=de}}</ref> (1892\u20131968) independently discovered that the magnetron could generate waves of 100 megahertz to 1 gigahertz.  \u017d\u00e1\u010dek, a professor at Prague's [[Charles University]], published first; however, he published in a journal with a small circulation and thus attracted little attention.<ref>See:\n*  {{cite journal|last1=\u017d\u00e1\u010dek|first1=A.|title=Nov\u00e1 metoda k vytvoren\u00ed netlumenych oscilac\u00ed|journal=\u010casopis Pro P\u011bstov\u00e1n\u00ed Matematiky a Fysiky|date=May 1924|volume=53|pages=378\u201380|doi=10.21136/CPMF.1924.121857|trans-title=New method of generating undamped oscillations|language=cs|doi-access=free}}  Available (in Czech) at: [http://dml.cz/bitstream/handle/10338.dmlcz/121857/CasPestMatFys_053-1924-3_4.pdf Czech Digital Mathematics Library] {{webarchive|url=https://web.archive.org/web/20110718171331/http://dml.cz/bitstream/handle/10338.dmlcz/121857/CasPestMatFys_053-1924-3_4.pdf |date=2011-07-18 }}.\n*  {{cite journal|last1=\u017d\u00e1\u010dek|first1=A.|title=\u00dcber eine Methode zur Erzeugung von sehr kurzen elektromagnetischen Wellen|journal=Zeitschrift f\u00fcr Hochfrequenztechnik|date=1928|volume=32|pages=172\u201380|trans-title=On a method for generating very short electromagnetic waves|language=de}}\n*  \u017d\u00e1\u010dek, A., "Spojen\u00ed pro v\u00fdrobu elektrick\u00fdch vln" [Circuit for the production of electrical waves], Czechoslovak patent no. 20,293 (filed: 31 May 1924; issued: 15 February 1926). Available (in Czech) at: [http://spisy.upv.cz/Patents/FirstPages/FPPV0020/0020293.pdf Czech Industrial Property Office] {{webarchive|url=https://web.archive.org/web/20110718185717/http://spisy.upv.cz/Patents/FirstPages/FPPV0020/0020293.pdf |date=2011-07-18 }}.</ref> Habann, a student at the [[University of Jena]], investigated the magnetron for his doctoral dissertation of 1924.<ref>{{cite journal|last1=Habann|first1=Erich|title=Eine neue Generatorr\u00f6hre|journal=Zeitschrift f\u00fcr Hochfrequenztechnik|date=1924|volume=24|pages=115\u201320, 135\u201341|trans-title=A new generator tube|language=de}}</ref> Throughout the 1920s, Hull and other researchers around the world worked to develop the magnetron.<ref name=Kaiser>{{cite book|last1=Kaiser|first1=W.|editor1-last=Blumtritt|editor1-first=O.|editor2-last=Petzold|editor2-first=H.|editor3-last=Aspray|editor3-first=W.|title=Tracking the History of Radar|date=1994|publisher=IEEE|location=Piscataway, NJ|pages=217\u201336|chapter=The Development of Electron Tubes and of Radar technology: The Relationship of Science and Technology}}</ref><ref>{{cite journal|last1=Brittain|first1=James E.|title=The magnetron and the beginnings of the microwave age|journal=Physics Today|date=1985|volume=38|issue=7|pages=60\u201367|doi=10.1063/1.880982|bibcode=1985PhT....38g..60B}}</ref><ref>See for example: \n*  Soviet physicists: \n:* {{cite journal|last1=Slutskin|first1=Abram A.|last2=Shteinberg|first2=Dmitry S.|title=[Obtaining oscillations in cathode tubes with the aid of a magnetic field]|journal=\u0416\u0443\u0440\u043d\u0430\u043b \u0420\u0443\u0441\u0441\u043a\u043e\u0433\u043e \u0424\u0438\u0437\u0438\u043a\u043e-\u0425\u0438\u043c\u0438\u0447\u0435\u0441\u043a\u043e\u0433\u043e \u041e\u0431\u0449\u0435\u0441\u0442\u0432\u0430 [Zhurnal Russkogo Fiziko-Khimicheskogo Obshchestva, Journal of the Russian Physico-Chemical Society]|date=1926|volume=58|issue=2|pages=395\u2013407|language=ru}} \n:* {{cite journal|last1=Slutskin|first1=Abram A.|last2=Shteinberg|first2=Dmitry S.|title=[Electronic oscillations in two-electrode tubes]|journal=\u0423\u043a\u0440\u0430\u0457\u043d\u0441\u044c\u043a\u0438\u0439 \u0444\u0456\u0437\u0438\u0447\u043d\u0438\u0439 \u0436\u0443\u0440\u043d\u0430\u043b [Ukrainski Fizychni Zapysky, Ukrainian Journal of Physics]|date=1927|volume=1|issue=2|pages=22\u201327|language=uk}}\n:* {{cite journal|last1=Slutzkin|first1=A. A.|last2=Steinberg|first2=D. S.|title=Die Erzeugung von kurzwelligen unged\u00e4mpften Schwingungen bei Anwendung des Magnetfeldes|journal=Annalen der Physik|date=May 1929|volume=393|issue=5|pages=658\u201370|trans-title=The generation of undamped shortwave oscillations by application of a magnetic field|language=de|doi=10.1002/andp.19293930504|bibcode=1929AnP...393..658S}}\n*  Japanese engineers: \n:* {{cite journal|last1=Yagi|first1=Hidetsugu|title=Beam transmission of ultra-short waves|journal=Proceedings of the Institute of Radio Engineers|date=1928|volume=16|issue=6|pages=715\u201341}} Magnetrons are discussed in Part II of this article.\n:* {{cite journal|last1=Okabe|first1=Kinjiro|journal=Journal of the Institute of Electrical Engineering of Japan|date=March 1928|pages=284ff|title=[Production of intense extra-short radio waves by a split-anode magnetron (Part 3)]|language=ja}}\n:* {{cite journal|last1=Okabe|first1=Kinjiro|title=On the short-wave limit of magnetron oscillations|journal=Proceedings of the Institute of Radio Engineers|date=1929|volume=17|issue=4|pages=652\u201359}}\n:* {{cite journal|last1=Okabe|first1=Kinjiro|title=On the magnetron oscillation of new type|journal=Proceedings of the Institute of Radio Engineers|date=1930|volume=18|issue=10|pages=1748\u201349}}</ref> Most of these early magnetrons were glass vacuum tubes with multiple anodes. However, the two-pole magnetron, also known as a split-anode magnetron, had relatively low efficiency.\n\nWhile [[radar]] was being developed during [[World War II]], there arose an urgent need for a high-power [[microwave]] generator that worked at shorter [[wavelength]]s, around 10 cm (3 GHz), rather than the 50 to 150 cm (200 MHz) that was available from tube-based generators of the time. It was known that a multi-cavity resonant magnetron had been developed and patented in 1935 by [[Hans Hollmann]] in [[Berlin]].<ref name=Hollmann>Hollmann, Hans Erich, [http://pdfpiw.uspto.gov/.piw?Docid=02123728 "Magnetron,"] {{webarchive|url=https://web.archive.org/web/20180114184047/http://pdfpiw.uspto.gov/.piw?Docid=02123728 |date=2018-01-14 }} U.S. patent no. 2,123,728 (filed:  1936 November 27 ; issued:  1938 July 12).</ref> However, the German military considered the frequency drift of Hollman's device to be undesirable, and based their radar systems on the [[klystron]] instead.  But klystrons could not at that time achieve the high power output that magnetrons eventually reached.  This was one reason that German [[night fighter]] radars, which never strayed beyond the [[Lichtenstein radar#FuG 202 Lichtenstein B/C|low-UHF band to start with]] for front-line aircraft, were not a match for their British counterparts.<ref name=Kaiser/>{{rp|229}} Likewise, in the UK, [[Albert Beaumont Wood]] proposed in 1937 a system with "six or eight small holes" drilled in a metal block, differing from the later production designs only in the aspects of vacuum sealing. However, his idea was rejected by the Navy, who said their valve department was far too busy to consider it.<ref>{{cite book |url=https://books.google.com/books?id=H9W-DAAAQBAJ |title=The Development of Radar Equipments for the Royal Navy, 1935\u201345 |first=F.A. |last=Kingsley |date=2016 |url-status=live |archive-url=https://web.archive.org/web/20180505184048/https://books.google.com/books?id=H9W-DAAAQBAJ |archive-date=2018-05-05 |isbn=9781349134571 }}</ref>\n\n[[File:R&B Magnetron.jpg|thumb|[[John Randall (physicist)|Sir John Randall]] and [[Harry Boot]]'s original cavity magnetron developed in 1940 at the [[University of Birmingham]], England]]\n[[File:Manetron Magnet.jpg|thumb|The electromagnet used in conjunction with Randall and Boot's original magnetron]]\n[[File:Original cavity magnetron, 1940 (9663811280).jpg|thumb|right|The anode block which is part of the cavity magnetron developed by Randall and Boot]]\nIn 1940, at the [[University of Birmingham]] in the UK, [[John Randall (physicist)|John Randall]] and [[Harry Boot]] produced a working prototype of a cavity magnetron that produced about 400 W.<ref name="Magnetron"/> Within a week this had improved to 1 kW, and within the next few months, with the addition of water cooling and many detail changes, this had improved to 10 and then 25 kW.<ref name="Magnetron"/> To deal with its drifting frequency, they sampled the output signal and synchronized their receiver to whatever frequency was actually being generated. In 1941, the problem of frequency instability was solved by [[James Sayers (physicist)|James Sayers]] coupling ("strapping") alternate cavities within the magnetron which reduced the instability by a factor of 5\u20136.<ref>{{cite web|url=http://www.radarpages.co.uk/oral/scanlan/cmr/scanlan3.htm|title=M.J.B.Scanlan; Early Centimetric Ground Radars \u2013 A Personal Reminiscence|first=Dick|last=Barrett|website=www.radarpages.co.uk|access-date=5 May 2018|url-status=live|archive-url=https://web.archive.org/web/20160304002432/http://www.radarpages.co.uk/oral/scanlan/cmr/scanlan3.htm|archive-date=4 March 2016}}</ref> (For an overview of early magnetron designs, including that of Boot and Randall, see <ref>{{cite journal|last=Willshaw|first=W. E.|author2=L. Rushforth |author3=A. G. Stainsby |author4=R. Latham |author5=A. W. Balls |author6=A. H. King |title=The high-power pulsed magnetron: development and design for radar applications|journal=Journal of the Institution of Electrical Engineers - Part IIIA: Radiolocation|year=1946|volume=93|issue=5|pages=985\u20131005|doi=10.1049/ji-3a-1.1946.0188|url=https://ieeexplore.ieee.org/document/5299321|access-date=22 June 2012}}</ref>) According to Andy Manning from the [[RAF Air Defence Radar Museum]], Randall and Boot's discovery was "a massive, massive breakthrough" and "deemed by many, even now, to be the most important invention that came out of the Second World War", while professor of military history at the [[University of Victoria]] in British Columbia, David Zimmerman, states:\n\n{{quote|The magnetron remains the essential radio tube for shortwave radio signals of all types. It not only changed the course of the war by allowing us to develop airborne radar systems, it remains the key piece of technology that lies at the heart of your microwave oven today. The cavity magnetron's invention changed the world.<ref name="Magnetron"/>}}\n\nBecause France had just fallen to the [[Nazi]]s and Britain had no money to develop the magnetron on a massive scale, [[Winston Churchill]] agreed that [[Henry Tizard|Sir Henry Tizard]] should offer the magnetron to the Americans in exchange for their financial and industrial help.<ref name="Magnetron"/> An early 10 [[Kilowatt|kW]] version, built in England by the [[General Electric Company plc|General Electric Company]] Research Laboratories, [[Wembley]], [[London]] (not to be confused with the similarly named American company General Electric), was taken on the [[Tizard Mission]] in September 1940. As the discussion turned to radar, the US Navy representatives began to detail the problems with their short-wavelength systems, complaining that their klystrons could only produce 10 W. With a flourish, [[Edward George Bowen|"Taffy" Bowen]] pulled out a magnetron and explained it produced 1000 times that.<ref name="Magnetron"/><ref>{{cite news|last1=Harford|first1=Tim|title=How the search for a 'death ray' led to radar|url=https://www.bbc.co.uk/news/business-41188464|access-date=9 October 2017|work=BBC World Service|date=9 October 2017|quote=The magnetron stunned the Americans. Their research was years off the pace.|url-status=live|archive-url=https://web.archive.org/web/20171009003404/http://www.bbc.co.uk/news/business-41188464|archive-date=9 October 2017}}</ref>\n\n[[Bell Telephone Laboratories]] took the example and quickly began making copies, and before the end of 1940, the [[Radiation Laboratory]] had been set up on the campus of the [[Massachusetts Institute of Technology]] to develop various types of radar using the magnetron. By early 1941, portable centimetric airborne radars were being tested in American and British aircraft.<ref name="Magnetron">{{cite news |url=http://news.bbc.co.uk/1/hi/sci/tech/6331897.stm |title=Briefcase 'that changed the world' |work=BBC News |author=Angela Hind |date=February 5, 2007 |access-date=2007-08-16 |url-status=live |archive-url=https://web.archive.org/web/20071115140606/http://news.bbc.co.uk/1/hi/sci/tech/6331897.stm |archive-date=November 15, 2007 }}</ref> In late 1941, the [[Telecommunications Research Establishment]] in the United Kingdom used the magnetron to develop a revolutionary airborne, ground-mapping radar codenamed H2S. The [[H2S radar]] was in part developed by [[Alan Blumlein]] and [[Bernard Lovell]].\n\nThe cavity magnetron was widely used during [[World War II]] in microwave radar equipment and is often credited with giving Allied radar a considerable performance advantage over [[Germany|German]] and [[Japan]]ese radars, thus directly influencing the outcome of the war. It was later described by American historian [[James Phinney Baxter III]] as "[t]he most valuable cargo ever brought to our shores".<ref>{{cite book|last1=Baxter|first1=James Phinney (III)|title=Scientists Against Time|date=1946|publisher=Little, Brown, and Co.|location=Boston, Massachusetts|page=142}} (Baxter was the official historian of the Office of Scientific Research and Development.)</ref>\n\nCentimetric radar, made possible by the cavity magnetron, allowed for the detection of much smaller objects and the use of much smaller antennas. The combination of small-cavity magnetrons, small antennas, and high resolution allowed small, high quality radars to be installed in aircraft. They could be used by maritime patrol aircraft to detect objects as small as a submarine periscope, which allowed aircraft to attack and destroy submerged submarines which had previously been undetectable from the air. Centimetric contour mapping radars like [[H2S radar|H2S]] improved the accuracy of Allied bombers used in the [[strategic bombing during World War II|strategic bombing campaign]], despite the existence of the German [[Naxos radar detector|FuG 350 ''Naxos'']] device to specifically detect it. Centimetric gun-laying radars were likewise far more accurate than the older technology. They made the big-gunned Allied battleships more deadly and, along with the newly developed [[proximity fuze]], made anti-aircraft guns much more dangerous to attacking aircraft. The two coupled together and used by anti-aircraft batteries, placed along the flight path of German [[V-1 flying bomb]]s on their way to [[London]], are credited with destroying many of the flying bombs before they reached their target.\n\nSince then, many millions of cavity magnetrons have been manufactured; while some have been for radar the vast majority have been for [[microwave oven]]s. The use in radar itself has dwindled to some extent, as more accurate signals have generally been needed and developers have moved to [[klystron]] and [[traveling-wave tube]] systems for these needs."}},
{"article_title": "Adobe Flash", "pageid": "20947", "revid": "1061668051", "timestamp": "2021-12-23T03:53:38Z", "history_paths": [["Adobe Flash --- Introduction ---", "History"]], "categories": ["adobe flash", "1993 software", "adobe software", "american inventions", "c++ software", "computing platforms", "cross-platform software", "discontinued adobe software", "macintosh multimedia software", "macos multimedia software", "macromedia software", "video game development software", "windows multimedia software", "obsolete technologies"], "heading_tree": {"Adobe Flash --- Introduction ---": {"Applications": {"Websites": {}, "Rich Web Applications": {}, "Video games": {}, "Film and animation": {}}, "History": {"FutureWave": {}, "Macromedia": {}, "Adobe": {}, "Open Source": {"Open Screen Project": {}}, "End of life": {"Post EOL support": {}}, "Content preservation projects": {}}, "Format": {"FLA": {}, "SWF": {}, "3D": {}, "Flash Video": {}, "Flash Audio": {}, "ActionScript": {}, "Specifications": {}}, "Animation tools": {"Official tools": {}, "Third-party tools": {}}, "Programming tools": {"Official tools": {}, "Third-party tools": {}}, "Players": {"Proprietary": {}, "Open source": {}}, "Availability": {"Desktop computers": {"Adobe Flash Player": {}, "Adobe AIR": {}}, "Mobile devices": {"Adobe Flash Player": {}, "Adobe AIR": {}}, "Portable electronic devices": {}}, "{{vanchor|Alternatives}} on the web": {"OpenFL": {}, "HTML5": {}, "Flash to HTML5": {}}, "Criticisms": {"Mobile support": {}, "Vendor lock-in": {}, "Accessibility and usability": {}, "Flash blocking in web browsers": {}, "Security": {}, "Flash cookies": {}}, "See also": {}, "Explanatory footnotes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Adobe Flash --- Introduction ---|History": "The precursor to Flash was SmartSketch, a product published by [[FutureWave Software]] in 1993. The company was founded by [[Charlie Jackson (software)|Charlie Jackson]], [[Jonathan Gay]], and Michelle Welsh.<ref name="hs">[http://www.coldhardflash.com/2008/02/grandmasters-of-flash-an-interview-with-the-creators-of-flash.html Grandmasters of Flash: An Interview with the Creators of Flash], Cold Hard Flash</ref><ref name="mfb">[http://digital-archaeology.org/flash-back/ MACROMEDIA FLASH BACK], Digital Archaeology</ref><ref name="bh1">[https://books.google.com/books?id=tnckAQAAMAAJ PC Graphics & Video, Volume 6, Issues 1\u20136], Advanstar Communications, 1997</ref><ref name="bh2">[https://books.google.com/books?id=Tn8qAQAAMAAJ Personal Computer Magazine], PC Communications Corporation, 1995</ref> SmartSketch was a vector drawing application for pen computers running the [[PenPoint OS]].<ref>{{cite web|url=http://www.flashmagazine.com/413.htm |title=The Flash History |access-date=June 18, 2001 |last=Waldron |first=Rick |date=August 27, 2006 |publisher=Flashmagazine }}</ref><ref>{{cite web\n |last=Gay\n |first=Jonathan\n |author-link=Jonathan Gay\n |title=The History of Flash\n |publisher=Adobe Systems Inc.\n |year=2001\n |url=https://www.adobe.com/macromedia/events/john_gay/page02.html\n |access-date=October 18, 2009\n |url-status=dead\n |archive-url=https://web.archive.org/web/20090204162951/http://www.adobe.com/macromedia/events/john_gay/page02.html\n |archive-date=February 4, 2009\n}}</ref> When PenPoint failed in the marketplace, SmartSketch was ported to [[Microsoft Windows]] and [[Classic Mac OS|Mac OS]].<ref name="mfb"/><ref name="Back to Graphics">[https://www.adobe.com/macromedia/events/john_gay/page03.html The History of Flash: Back to Graphics] {{webarchive|url=https://web.archive.org/web/20150101204138/https://www.adobe.com/macromedia/events/john_gay/page03.html |date=January 1, 2015 }}</ref>\n\nAs the Internet became more popular, FutureWave realized the potential for a vector-based web animation tool that might challenge [[Macromedia]] [[Adobe Shockwave|Shockwave]] technology.<ref name="hs"/><ref name="mfb"/> In 1995, FutureWave modified SmartSketch by adding frame-by-frame animation features and released this new product as FutureSplash Animator on Macintosh and PC.<ref name="hs"/><ref name="mfb"/><ref name="The Dawn of Web Animation">[https://www.adobe.com/macromedia/events/john_gay/page04.html The History of Flash: The Dawn of Web Animation] {{webarchive|url=https://web.archive.org/web/20080125045402/http://www.adobe.com/macromedia/events/john_gay/page04.html |date=January 25, 2008 }}</ref><ref>{{cite web| url=http://coldhardflash.com/2008/02/grandmasters-of-flash-an-interview-with-the-creators-of-flash.html | title=Grandmasters of Flash: An Interview with the Creators of Flash | access-date=February 12, 2008 | publisher=ColdHardFlash.com}}</ref>\n\nFutureWave approached [[Adobe Systems]] with an offer to sell them FutureSplash in 1995, but Adobe turned down the offer at that time.<ref name="mfb"/> Microsoft wanted to create an "online TV network" ([[MSN Dial-up#MSN 2.0|MSN 2.0]]) and adopted FutureSplash animated content as a central part of it.<ref name="mfb"/> [[Disney Online]] used FutureSplash animations for their subscription-based service Disney's Daily Blast.<ref name="hs"/><ref name="mfb"/> [[Fox Broadcasting Company]] launched [[The Simpsons]] using FutureSplash.<ref name="mfb"/>\n\n In November 1996, FutureSplash was acquired by Macromedia, and Macromedia re-branded and released ''FutureSplash Animator'' as ''Macromedia Flash 1.0''. Flash was a two-part system, a graphics and animation editor known as Macromedia Flash, and a player known as Macromedia Flash Player.{{Citation needed|date=January 2021}}\n\n''FutureSplash Animator'' was an animation tool originally developed for pen-based computing devices. Due to the small size of the ''FutureSplash Viewer'', it was particularly suited for download on the Web. Macromedia distributed Flash Player as a free browser [[Plug-in (computing)|plugin]] in order to quickly gain market share. By 2005, more computers worldwide had Flash Player installed than any other Web media format, including [[Java (software platform)|Java]], [[QuickTime]], [[RealNetworks]], and [[Windows Media Player]].<ref name="flash2005">{{cite news|url=http://news.zdnet.co.uk/internet/0,1000000097,39211831,00.htm |title=Flash Player in 2005 |work=[[ZDNet]] |access-date=2008-12-26 |archive-url=https://web.archive.org/web/20070516090612/http://news.zdnet.co.uk/internet/0%2C1000000097%2C39211831%2C00.htm |archive-date=May 16, 2007 |url-status=dead }}</ref>\n\nMacromedia upgraded the Flash system between 1996 and 1999 adding MovieClips, Actions (the precursor to ActionScript), Alpha transparency, and other features. As Flash matured, Macromedia's focus shifted from marketing it as a graphics and media tool to promoting it as a [[Web application]] platform, adding scripting and data access capabilities to the player while attempting to retain its small footprint.{{Citation needed|date=January 2021}}\n\nIn 2000, the first major version of ActionScript was developed, and released with ''Flash 5''. Actionscript 2.0 was released with ''Flash MX 2004'' and supported [[object-oriented programming]], improved UI components and other programming features. The last version of Flash released by Macromedia was ''Flash 8'', which focused on graphical upgrades such as filters (blur, drop shadow, etc.), blend modes (similar to [[Adobe Photoshop]]), and advanced features for [[Flash Video|FLV video]].{{Citation needed|date=January 2021}}\n\n On December 3, 2005, Adobe Systems acquired Macromedia<ref>{{Cite news|last=Flynn|first=Laurie J.|date=2005-04-19|title=Adobe Buys Macromedia for $3.4 Billion (Published 2005)|language=en-US|work=The New York Times|url=https://www.nytimes.com/2005/04/19/technology/adobe-buys-macromedia-for-34-billion.html|access-date=2021-03-04|issn=0362-4331}}</ref> along with the entire Macromedia product line including Flash, [[Adobe Dreamweaver|Dreamweaver]], [[Adobe Director|Director]]/[[Adobe Shockwave|Shockwave]], [[Adobe Fireworks|Fireworks]], and [[Authorware]].{{Citation needed|date=January 2021}}\n\nIn 2007, Adobe's first version release was ''Adobe Flash CS3 Professional'', the ninth major version of Flash. It introduced the ActionScript 3.0 programming language, which supported modern programming practices and enabled business applications to be developed with Flash. [[Adobe Flex Builder]] (built on [[Eclipse (software)|Eclipse]]) targeted the enterprise [[Software development|application development]] market, and was also released the same year. Flex Builder included the Flex SDK, a set of components that included charting, advanced UI, and data services (''Flex Data Services'').{{Citation needed|date=January 2021}}\n\nIn 2008, Adobe released the tenth version of Flash, ''Adobe Flash CS4''. Flash 10 improved animation capabilities within the Flash editor, adding a motion editor panel (similar to [[Adobe After Effects]]), [[inverse kinematics]] (bones), basic 3D object animation, object-based animation, and other text and graphics features. ''Flash Player 10'' included an in-built 3D engine (without GPU acceleration) that allowed basic object transformations in 3D space (position, rotation, scaling).{{Citation needed|date=January 2021}}\n\nAlso in 2008, Adobe released the first version of Adobe Integrated Runtime (later re-branded as ''Adobe AIR''), a runtime engine that replaced Flash Player, and provided additional capabilities to the ActionScript 3.0 language to build desktop and mobile applications. With AIR, developers could access the file system (the user's files and folders), and connected devices such as a joystick, gamepad, and sensors for the first time.{{Citation needed|date=January 2021}}\n\nIn 2011, ''Adobe Flash Player 11'' was released, and with it the first version of [[Stage3D]], allowing GPU-accelerated 3D rendering for Flash applications and games on desktop platforms such as [[Microsoft Windows]] and [[macOS|Mac OS X]].<ref name="Labrecque2011">{{cite book|author =Joseph Labrecque|title=What's New in Flash Player 11|url=https://books.google.com/books?id=UGD4zMFnK0QC&pg=PA17|year=2011|publisher=O'Reilly Media, Inc.|isbn=978-1-4493-1110-0|page=17}}</ref> Adobe further improved 3D capabilities from 2011 to 2013, adding support for 3D rendering on Android and iOS platforms, alpha-channels, compressed textures, [[texture atlas]]es, and other features.<ref name="fproadmap">[https://www.adobe.com/devnet/flashplatform/whitepapers/roadmap.html Adobe Flash Roadmap], Adobe</ref><ref>[http://www.bytearray.org/?p=4516] {{Webarchive|url=https://web.archive.org/web/20150707181514/http://www.bytearray.org/?p=4516 |date=July 7, 2015 }} Introducing Flash Player 11.4/AIR 3.4 beta!, by Thibault Imbert (Adobe employee), ByteArray</ref> Adobe AIR was upgraded to support 64-bit computers, and to allow developers to add additional functionality to the AIR runtime using ''AIR Native Extensions'' (ANE).\n\nIn May 2014, Adobe announced that Adobe AIR was used in over 100,000 unique applications and had over 1 billion installations logged worldwide.<ref>{{Cite web|date=2014-05-09|title=1 Billion AIR Installations|url=https://forta.com/2014/05/10/1-billion-air-installations/|access-date=2021-03-04|website=Ben Forta|language=en-US}}</ref> Adobe AIR was voted the ''Best Mobile Application Development'' product at the [[Consumer Electronics Show]] on two consecutive years (CES 2014 and CES 2015).<ref>[http://www.compassintelligence.com/?q=press/compass-intelligence-announces-winners-2014-mobility-awards-wireless-m2m-and-green-technology Compass Intelligence Announces Winners of the 2014 Mobility Awards], Compass Intelligence</ref><ref>[http://www.compassintelligence.com/?q=press/compass-intelligence-announces-winners-2015-mobility-awards-list-m2m-green-technology-and Compass Intelligence Announces Winners of the 2015 Mobility Awards], Compass Intelligence</ref>\n\nIn 2016, Adobe renamed Flash Professional, the primary authoring software for Flash content, to [[Adobe Animate]] to reflect its growing use for authoring HTML5 content in favor of Flash content.<ref>{{Cite news|url=https://www.wired.com/2015/12/adobe-flash-is-dead-in-name-only/|title=Sadly, Adobe Flash Isn't Dead. It Just Changed Its Name|last=Barrett|first=Brian|work=WIRED|access-date=2017-06-22|language=en-US}}</ref>\n\n Adobe has taken steps to reduce or eliminate Flash licensing costs. For instance, the [[SWF]] file format documentation is provided free of charge<ref>[https://www.adobe.com/devnet/swf.html SWF Technology Center | Adobe Developer Connection] {{Webarchive|url=https://web.archive.org/web/20140822131849/http://www.adobe.com/devnet/swf.html|date=August 22, 2014}}. Adobe.com (July 14, 2009). Retrieved on March 11, 2011.</ref> after they relaxed the requirement of accepting a [[non-disclosure agreement]] to view it in 2008.<ref>{{cite web|title=Adobe Open Screen Project|website=[[ZDNet]]|url=http://www.zdnet.com/blog/stewart/adobe-open-screen-project/828|url-status=live|archive-url=https://web.archive.org/web/20110811085142/http://www.zdnet.com/blog/stewart/adobe-open-screen-project/828|archive-date=August 11, 2011|access-date=March 21, 2012|quote=Starting today, there will be no restrictions on the use of the SWF specification or the FLV and F4V specifications that make up video in Flash. Formerly, to look at the SWF specification users had to sign a licensing agreement not to use it to create competing players}}</ref> Adobe also created the Open Screen Project which removes licensing fees and opens data protocols for Flash.\n\nAdobe has also open-sourced many components relating to Flash.\n\n* In 2006, the [[ActionScript Virtual Machine 2]] (AVM2) which implements [[ActionScript 3]] was donated as open-source to [[Mozilla Foundation]], to begin work on the [[Tamarin (software)|Tamarin]] virtual machine that would implement the [[ECMAScript 4]] language standard with the help of the [[Mozilla]] community.<ref>{{cite web|date=November 7, 2006|title=Adobe and Mozilla Foundation to Open Source Flash Player Scripting Engine|url=http://www.mozilla.com/en-US/press/mozilla-2006-11-07.html|url-status=live|archive-url=https://web.archive.org/web/20101021012819/http://www.mozilla.com/en-US/press/mozilla-2006-11-07.html|archive-date=October 21, 2010|access-date=September 3, 2010|work=Mozilla Foundation Press Center|location=San Francisco}}</ref> It was released under the terms of a [[Mozilla Public License|MPL]]/[[GPL]]/[[LGPL]] [[tri-license]] and includes the specification for the ActionScript [[bytecode]] format; [[Tamarin Project]] jointly managed by Mozilla and Adobe Systems<ref>[https://www.mozilla.org/projects/tamarin/ Tamarin Project] {{webarchive|url=https://web.archive.org/web/20070210002959/http://www.mozilla.org/projects/tamarin/|date=February 10, 2007}}. Mozilla.org (October 5, 2010). Retrieved on March 11, 2011.</ref> It is now considered obsolete by Mozilla.\n* In 2011, the [[Apache Flex|Adobe Flex Framework]] was donated as open-source to the [[Apache Software Foundation]] and rebranded as Apache Flex.<ref name="Adobe donates Flex to Apache">{{cite web|title=Adobe donates Flex to Apache|url=http://www.techworld.com.au/article/407714/adobe_donates_flex_apache|url-status=live|archive-url=https://web.archive.org/web/20111118101841/http://www.techworld.com.au/article/407714/adobe_donates_flex_apache/|archive-date=November 18, 2011|access-date=November 17, 2011|website=[[Techworld]]}}</ref> Some saw this move as Adobe abandoning Flex, and stepping away from the Flash Platform as a whole.<ref name="thereg1">{{cite web|author=Tim Anderson|date=November 15, 2015|title=Adobe Flex SDK bombshell STUNS developers|website=[[The Register]]|url=https://www.theregister.co.uk/2011/11/15/adobe_donates_flex_sdk_to_open_source/|url-status=live|archive-url=https://web.archive.org/web/20170810172248/https://www.theregister.co.uk/2011/11/15/adobe_donates_flex_sdk_to_open_source/|archive-date=August 10, 2017|access-date=August 10, 2017}}</ref><ref name="pcworld1">{{cite web|author=Joab Jackson, IDG News Service|date=November 16, 2011|title=Adobe Donates Flex to Apache|url=http://www.pcworld.com/article/244060/adobe_donates_flex_to_apache.html|url-status=live|archive-url=https://www.webcitation.org/6CfUBk4Pj?url=http://www.pcworld.com/article/244060/adobe_donates_flex_to_apache.html|archive-date=December 4, 2012|access-date=October 10, 2015|publisher=[[PCWorld]]}}</ref> Sources from Apache say that "Enterprise application development is no longer a focus at Adobe. At least as Flash is concerned, Adobe is concentrating on games and video.",<ref name="thereg1" /><ref name="printui1">[http://printui.com/blog/2013/01/flex-flash/ Flex != Flash] {{Webarchive|url=https://web.archive.org/web/20160110220042/http://printui.com/blog/2013/01/flex-flash/|date=January 10, 2016}}, PrintUI, January 27, 2013</ref> and they conclude that "Flex Innovation is Exploding!".<ref name="printui1" /> The donated source code included a partly developed AS3 compiler (dubbed "Falcon") and the [[BlazeDS]] set of technologies.<ref name="pcworld1" /><ref name="printui1" />\n* In 2013, the [[CrossBridge]] C++ [[cross-compilation]] toolset was open sourced by Adobe and released on [[GitHub]].<ref name="labsblog4">[http://blogs.adobe.com/flashplayer/2013/06/open-source-flash-c-compiler-crossbridge.html Open Source Flash C++ Compiler, CrossBridge] {{Webarchive|url=https://web.archive.org/web/20140325084106/http://blogs.adobe.com/flashplayer/2013/06/open-source-flash-c-compiler-crossbridge.html|date=March 25, 2014}}, Adobe Blogs, June 25, 2013</ref><ref>[https://adobe-flash.github.io/crossbridge/ CrossBridge] {{Webarchive|url=https://web.archive.org/web/20170920190506/http://adobe-flash.github.io/crossbridge/|date=September 20, 2017}}, Adobe Gaming GitHub Website</ref> The project was formerly termed "Alchemy" and "Flash Runtime C++ Compiler", and targeted the game development market to enable C++ video games to run in Adobe Flash Player.<ref>[https://www.phoronix.com/scan.php?page=news_item&px=MTM5NjA Adobe Open-Sources Flash C/C++ Compiler] {{Webarchive|url=https://web.archive.org/web/20170206072221/https://www.phoronix.com/scan.php?page=news_item&px=MTM5NjA|date=February 6, 2017}}, Phoronix, Michael Larabel, June 26, 2013</ref>\n\nAdobe has not been willing to make complete source code of the Flash Player available for [[free software]] development and even though [[free and open source]] alternatives such as [[Shumway (software)|Shumway]] and [[Gnash (software)|Gnash]] have been built, they are no longer under active development.<ref>{{cite web|title=Gnash Reference Manual|url=https://www.gnu.org/software/gnash/manual/gnashref.html#runs-on|url-status=live|archive-url=https://web.archive.org/web/20111125173326/http://www.gnu.org/software/gnash/manual/gnashref.html#runs-on|archive-date=November 25, 2011|access-date=November 12, 2011|website=gnu.org}}</ref> The only fully functional third-party Flash Player is the commercially available [[Scaleform GFx]] Player, which is game development [[middleware]] designed for integration into non-Flash [[video game]]s.{{Citation needed|date=October 2019}}\n\n On May 1, 2008, Adobe announced the ''Open Screen Project'', with the intent of providing a consistent application interface across devices such as personal computers, [[mobile device]]s, and [[consumer electronics]].<ref name="osppr">{{cite web|title=Adobe and Industry Leaders Establish Open Screen Project|url=https://www.adobe.com/aboutadobe/pressroom/pressreleases/200805/050108AdobeOSP.html|access-date=February 20, 2009|date=May 1, 2008|archive-url=https://web.archive.org/web/20090210215745/http://www.adobe.com/aboutadobe/pressroom/pressreleases/200805/050108AdobeOSP.html|archive-date=February 10, 2009|url-status=dead|df=mdy-all}}</ref> When the project was announced, seven goals were outlined: the abolition of licensing fees for Adobe Flash Player and [[Adobe AIR]], the removal of restrictions on the use of the [[Adobe Shockwave|Shockwave]] Flash ([[SWF]]) and Flash Video (FLV) [[file format]]s, the publishing of [[API|application programming interfaces]] for porting Flash to new devices, and the publishing of The Flash Cast protocol and Action Message Format (AMF), which let Flash applications receive information from remote databases.<ref name="osppr"/>\n\n{{As of|February 2009}}, the specifications removing the restrictions on the use of SWF and FLV/F4V specs have been published.<ref name="interview">{{cite web|url=http://www.uiresourcecenter.com/rich-internet-applications/articles/inside-the-open-screen-project.html?s=2_1 |title=Inside the Open Screen Project |first=Anup| last=Murarka|access-date=February 21, 2009| archive-url= https://web.archive.org/web/20090210122744/http://uiresourcecenter.com/rich-internet-applications/articles/inside-the-open-screen-project.html?s=2_1| archive-date= February 10, 2009 | url-status= live}}</ref> The Flash Cast protocol\u2014now known as the Mobile Content Delivery Protocol\u2014and AMF protocols have also been made available,<ref name="interview"/> with AMF available as an open source implementation, [[BlazeDS]].\n\nThe list of mobile device providers who have joined the project includes [[Palm, Inc.|Palm]], Motorola, and Nokia,<ref>{{cite web|url=http://www.openscreenproject.org/partners/current_partners.html| title=Open Screen Project partners|access-date=February 20, 2009| archive-url= https://web.archive.org/web/20090224150104/http://www.openscreenproject.org/partners/current_partners.html| archive-date= February 24, 2009 | url-status= live}}</ref> who, together with Adobe, have announced a $10 million Open Screen Project fund.<ref>{{cite web|title=Adobe and Nokia Announce $10 Million Open Screen Project Fund|url=https://www.adobe.com/aboutadobe/pressroom/pressreleases/200902/021609AdobeNokia.html|date=February 16, 2009|access-date=February 20, 2009|archive-url=https://web.archive.org/web/20090219070548/http://www.adobe.com/aboutadobe/pressroom/pressreleases/200902/021609AdobeNokia.html|archive-date=February 19, 2009|url-status=dead|df=mdy-all}}</ref> {{As of|2012}}, the Open Screen Project is no longer accepting new applications according to partner BSQuare. However, paid licensing is still an option for device makers who want to use Adobe software.{{citation needed|date=March 2016}}\n\n {{See also|Adobe Flash Player#End of life}}\nOne of Flash's primary uses on the Internet when it was first released was for building fully immersive, interactive websites. These were typically highly creative site designs that provided more flexibility over what the current HTML standards could provide as well as operate over dial-up connections.<ref name="bbc eol">{{cite web | url = https://www.bbc.com/news/technology-55497353 | title = Adobe Flash Player is finally laid to rest | first= Chris | last = Fox | date = December 31, 2020| access-date = December 31, 2020 | work = [[BBC News]] }}</ref> However, these sites limited accessibility by "breaking the [[Back button (hypertext)|Back Button]]", dumping visitors out of the Flash experience entirely by returning them to whatever page they had been on prior to first arriving at the site. Fully Flash-run sites fell out of favor for more strategic use of Flash plugins for video and other interactive features among standard HTML conventions, corresponding with the availability of HTML features like [[CSS|cascading style-sheets]] in the mid-00's.<ref>{{cite web | url = https://www.vice.com/en/article/d3awk7/flash-is-responsible-for-the-internets-most-creative-era | title = Flash Is Responsible for the Internet's Most Creative Era | first= Ernie | last = Smith | date= October 9, 2019 | access-date = November 24, 2020 | work = [[Vice (magazine)|Vice]] }}</ref> At the same time, this also led to Flash being used for new apps, including video games and animations.<ref name="gamasutra death">{{cite web | url = https://www.gamasutra.com/view/news/374253/The_forgotten_Flash_Website_movement_when_websites_were_the_new_emerging_artform.php | title = The forgotten Flash Website movement (when websites were 'the new emerging artform') | first= Nathalie | last = Lawhead | date = November 24, 2020 | access-date = November 24, 2020 | work = [[Gamasutra]] }}</ref> Precursors to [[YouTube]] but featuring user-generated Flash animations and games such as [[Newgrounds]] became popular destinations, further helping to spread the use of Flash.<ref name="bbc eol"/>\n\nToward the end of the millennium, the [[Wireless Application Protocol]] (WAP) was released, corresponding with development of [[Dynamic HTML]]. Fifteen years later, WAP had largely been replaced by full-capability implementations and the [[HTML5]] standard included more support for interactive and [[HTML5 video|video]] elements. Support for Flash in these mobile browsers was not included. In 2010, [[Apple, Inc.|Apple]]'s [[Steve Jobs]] famously wrote ''[[Thoughts on Flash]]'', an open letter to Adobe criticizing the closed nature of the Flash platform and the inherent security problems with the application to explain why Flash was not supported on [[iOS]].<ref>{{cite web |first=Jennifer |last=Valentino-Devries |title=Highlights: The Journal's Exclusive Interview With Adobe CEO |url=https://blogs.wsj.com/digits/2010/04/29/live-blogging-the-journals-interview-with-adobe-ceo/ |website=[[The Wall Street Journal]] |date=April 29, 2010 |access-date=June 19, 2017}}</ref><ref>{{cite web |first=Charles |last=Arthur |title=Adobe CEO hits back in row with Steve Jobs over Flash on Apple's iPhone |url=https://www.theguardian.com/technology/blog/2010/apr/29/adobe-chief-executive-flash-apple-reply |website=[[The Guardian]] |date=April 29, 2010 |access-date=June 19, 2017}}</ref> Adobe created the Adobe AIR environment as a means to appease Apple's concerns, and spent time legally fighting Apple over terms of its App Store to allow AIR to be used on the iOS. While Adobe eventually won, allowing for other third-party development environments to get access to the iOS, Apple's decision to block Flash itself was considered the "death blow" to the Flash application.<ref name="gamasutra death"/> In November 2011, about a year after Jobs' open letter, Adobe announced it would no longer be developing Flash and advised developers to switch to HTML5.<ref name="cnn jobs death blow">{{cite web | url = https://www.cnn.com/2011/11/09/tech/mobile/flash-steve-jobs/index.html | title = Did Steve Jobs kill Adobe Flash? | first = Doug | last = Gross | date = November 9, 2011 | access-date = February 4, 2021 | work = [[CNN]] }}</ref>\n\nIn 2011, Adobe ended support for Flash on Android.<ref name="cnn jobs death blow"/> Adobe stated that Flash platform was transitioning to Adobe AIR and [[OpenFL]], a multi-target open-source implementation of the Flash API.<ref name="intro">{{cite web|title=Introducing OpenFL|url=http://www.joshuagranick.com/blog/2013/05/30/introducing-openfl|website=Joshua Granick Blog|date=May 30, 2013}}</ref> In 2015, Adobe rebranded Flash Professional, the main Flash authoring environment, as [[Adobe Animate]] to emphasize its expanded support for HTML5 authoring, and stated that it would "encourage content creators to build with new web standards" rather than use Flash.<ref>{{Cite web|url=https://www.theverge.com/2015/12/1/9827778/stop-using-flash|title=Adobe is telling people to stop using Flash|last=Kastrenakes|first=Jacob|date=2015-12-01|website=The Verge|access-date=2017-07-25}}</ref>\n\nIn July 2017, Adobe [[deprecate]]d Flash, and announced its [[end-of-life (product)|End-Of-Life (EOL)]] at the end of 2020, and will cease support, distribution, and security updates for Flash Player.<ref name="Adobe Flash EOL"/>\n\nWith Flash's EOL announced, many browsers took steps to gradually restrict Flash content (caution users before launching it, eventually blocking all content without an option to play it). By January 2021, all major browsers were blocking all Flash content unconditionally. Only [[IE11]], niche browser forks, and some browsers built for [[China]] plan to continue support. Furthermore, excluding the China variant of Flash, Flash execution software has a built-in kill switch which prevents it from playing Flash after January 12, 2021.<ref>{{Cite web|last=Cimpanu|first=Catalin|title=Adobe to block Flash content from running on January 12, 2021|url=https://www.zdnet.com/article/adobe-to-block-flash-content-from-running-on-january-12-2021/|access-date=2021-02-18|website=ZDNet|language=en}}</ref> In January 2021, Microsoft released an optional update KB4577586 which removes Flash Player from Windows; in July 2021 this update was pushed out as a security update and applied automatically to all remaining systems.<ref>{{cite web | url = https://arstechnica.com/gadgets/2021/05/microsoft-will-remove-adobe-flash-from-windows-10-this-summer/ | title = Goodbye again, Flash\u2014Microsoft makes removal from Windows 10 mandatory | first = Jim | last=  Salter | date = May 5, 2021 | accessdate = May 5, 2021 | work = [[Ars Technica]] }}</ref>\n\n {{Main|Adobe Flash Player#Post-EOL support}}\nAdobe Flash will still be supported in China and worldwide on some specialized enterprise platforms beyond 2020.<ref name=Zhongcheng/>\n\n As early as 2014, around the same time that Adobe began encouraging Flash developers to transition their works to HTML5 standards, others began efforts to [[video game preservation|preserve]] existing Flash content through emulation of Flash in open standards. While some Flash applications were utilitarian, several applications had been shown to be experimental art, while others had laid the foundation of the [[independent game development|independent video game development]].<ref name="vice preservation"/> An early project was [[Mozilla]]'s [[Shumway (software)|Shumway]], an open source project that attempted to emulate the Flash standard in HTML5, but the project was shuttered as the team found that more developers were switching to HTML5 than seeking to keep their content in Flash, coupled with the difficulties in assuring full compatibility. Google had developed the [[Google Swiffy|Swiffy]] application, released in 2014, to convert Flash applications to HTML5-compatible scripts for viewing on mobile devices, but it was shut down in 2016.<ref name="vice preservation">{{cite web | url = https://www.vice.com/en/article/wx8y5y/tracing-the-sprawling-roots-of-flash-preservation | title = Tracing the Sprawling Roots of Flash Preservation | first= Khee Hoon | last=  Chan | date = March 18, 2021| access-date = March 18, 2021 |work = [[Vice (magazine)|Vice]] }}</ref>\n\nCloser to Flash's EOL date in 2020, there were more concentrated efforts simply to preserve existing Flash applications, including websites, video games, and animations beyond Flash's EOL.<ref name="gamasutra death" /><ref name="BlueMaxima">{{cite web|title=BlueMaxima's FlashPoint|url=http://bluemaxima.org/flashpoint/|access-date=18 July 2020|website=BlueMaxima|language=en}}</ref><ref name="FGA">{{cite web|title=Flash Game Archive - Preserve Flash Gaming|url=http://www.flashgamearchive.com/|access-date=18 July 2020|website=Flash Game Archive|language=en}}</ref> The [[Internet Archive]] introduced [[Ruffle (software)|Ruffle]] and Emularity Flash emulators to emulate Flash games and animations without the security holes in November 2020, opening a new collection for creators and users to save and preserve Flash content.<ref>{{cite web|last=Campbell|first=Ian Carlos|date=November 19, 2020|title=The Internet Archive is now preserving Flash games and animations|url=https://www.theverge.com/2020/11/19/21578616/internet-archive-preservation-flash-animations-games-adobe|access-date=November 19, 2020|work=[[The Verge]]}}</ref><ref>{{Cite web|last=Scott|first=Jason|date=2020-11-22|title=Flash Back! Further Thoughts on Flash at the Internet Archive|url=http://blog.archive.org/2020/11/22/flash-back-further-thoughts-on-flash-at-the-internet-archive/|access-date=2021-02-04|website=Internet Archive Blogs|language=en-US}}</ref> By January 2020, the [[BlueMaxima's Flashpoint|Flashpoint project]] collected more than 38,000 Flash applications, excluding those that were commercial products, and offered as a large freely available archive for users to download.<ref>{{cite web|last=Bailey|first=Dustin|date=February 1, 2020|title=Every Flash game disappears forever in 2020 \u2013 but this project has preserved 38,000 of them|url=https://www.pcgamesn.com/flash-games-2020-flashpoint|access-date=February 1, 2020|work=[[PCGamesN]]}}</ref><ref>{{cite news|last=Morton|first=Lauren|date=January 31, 2020|title=Flashpoint launcher is saving Flash games from impending extinction|url=https://www.rockpapershotgun.com/2020/01/31/flashpoint-launcher-is-saving-flash-games-from-impending-extinction/|access-date=February 1, 2020|website=[[Rock Paper Shotgun]]}}</ref> [[Kongregate]], one of the larger sites that offered Flash games, has been working with the [[The Strong|Strong Museum of Play]] to preserve its games.<ref name="vice preservation"/>"}},
{"article_title": "Brainwashing", "pageid": "20948", "revid": "1062854131", "timestamp": "2021-12-30T22:42:46Z", "history_paths": [["Brainwashing --- Introduction ---"], ["Brainwashing --- Introduction ---", "China and the Korean War"], ["Brainwashing --- Introduction ---", "In popular culture"], ["Brainwashing --- Introduction ---", "Legal cases and the \"brainwashing defense\""], ["Brainwashing --- Introduction ---", "Anti-cult movement"], ["Brainwashing --- Introduction ---", "Scientific research"], ["Brainwashing --- Introduction ---", "Other areas and studies"]], "categories": ["mind control", "anti-cult terms and concepts", "hypothetical technology", "paranormal terminology", "popular psychology", "psychological abuse"], "heading_tree": {"Brainwashing --- Introduction ---": {"China and the Korean War": {}, "In popular culture": {}, "Legal cases and the \"brainwashing defense\"": {}, "Anti-cult movement": {}, "Scientific research": {"American Psychological Association task force": {}, "Research by the US government": {}}, "Other areas and studies": {}, "See also": {}, "Further reading": {}, "Notes": {}, "External links": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Brainwashing --- Introduction ---": "{{Short description|Concept that the human mind can be altered or controlled}}\n{{Hatnote|Several terms redirect here. For other uses, see [[Brainwashing (disambiguation)]], [[Mind control (disambiguation)]], [[Re-education through labor]], [[indoctrination]], and [[Re-education camp (disambiguation)]]}}\n{{Use dmy dates|date=April 2015}}\n[[File:Brainwashing_1,_acr\u00edlico_sobre_lienzo,_100_x_80_cms.JPG|thumb|A satirical depiction of brainwashing]]\n'''Brainwashing''' (also known as '''mind control''', '''menticide''', '''coercive persuasion''',  '''thought control''', '''thought reform''', and '''re-education''') is the concept that the [[human mind]] can be altered or controlled by certain [[psychological]] techniques. Brainwashing is said to reduce its subjects' ability to [[think]] critically or independently, to allow the introduction of new, unwanted thoughts and ideas into their minds,<ref>{{cite book |title=Campbell's Psychiatric Dictionary |author=Campbell, Robert Jean |publisher=Oxford University Press |location=USA |year=2004 |page=403}}</ref> as well as to change their attitudes, values and beliefs.<ref>{{cite book |title=The Dictionary of Psychology |author=Corsini, Raymond J. |publisher=Psychology Press |year=2002 |page=127}}</ref><ref>{{cite book |author=Kowal, D.M. |year=2000 |contribution=Brainwashing |editor=Love, A.E. |title=Encyclopedia of Psychology |volume=1 |pages=463\u2013464 |publisher=American Psychological Association |doi=10.1037/10516-173}}</ref>\n\nThe term "brainwashing" was first used in English by [[Edward Hunter (U.S. journalist)|Edward Hunter]] in 1950 to describe how the [[Chinese government]] appeared to make people cooperate with them. Research into the concept also looked at [[Nazi Germany]], at some criminal cases in the United States, and at the actions of [[Human trafficking|human traffickers]]. In the late 1960s and 1970s, there was considerable [[scientific]] and [[legal]] debate, as well as media attention, about the possibility of brainwashing being a factor when [[Lysergic acid diethylamide]] (LSD) was used<ref>{{cite book |title=Encyclopaedic Dictionary of Religion |volume=2 |publisher=Gyan Publishing House |year=2005}}</ref> or in the conversion of young people to some [[new religious movements]], which were often referred to as [[cult]]s at the time.<ref>{{cite journal |last=Wright |first=Stuart |title=Media coverage of unconventional religion: Any "good news" for minority faiths? |journal=Review of Religious Research |date=December 1997 |volume=39 |issue=2 |pages=101\u2013115 |doi=10.2307/3512176 |jstor=3512176}}</ref><ref name="Melton">{{cite web |first=J. Gordon |last=Melton |author-link=J. Gordon Melton |title=Brainwashing and the Cults: The rise and fall of a theory |url=http://www.cesnur.org/testi/melton.htm |publisher=Center for Studies on New Religions (CESNUR) |date=10 December 1999 |access-date=5 September 2009 |quote=Since the late 1980s, though a significant public belief in cult-brainwashing remains, the academic community-including scholars from psychology, sociology, and religious studies-have shared an almost unanimous consensus that the coercive persuasion / brainwashing thesis proposed by Margaret Singer and her colleagues in the 1980s is without scientific merit.}}</ref>  The concept of brainwashing is sometimes involved in [[lawsuits]], especially regarding [[child custody]]. It can also be a theme in [[science fiction]] and in [[political]] and  [[corporate culture]], but is not generally accepted as a [[scientific fact|scientific term]].<ref>{{cite book |title=New Religious Movements: Challenge and Response |url=https://books.google.com/books?id=bvem38QO9y0C |publisher=Routledge |date=2012-12-06 |df=dmy-all |isbn=9781134636969 |language=en |first=Frank |last=Usarski |page=238 |quote=... there has been until now a lack of any convincing scientific evidence which can be applied in a generalised form to show that involvement in a New Religious Movement has any destructive consequences for the psyche of the individual concerned. ... The fact that, in all the ensuing years, no one has succeeded in verifying beyond reasonable doubt any of these claims, has however, never been regarded as a reason to exonerate the groups in any way. ... Thus, up to the time of writing, there has not been one single successful, legal conviction of the Scientology Church, even though this group has come to be regarded as the most dangerous of the new religious organisations. ... The fact that even long-term investigations have as yet failed to produce the desired results continues to be ignored. |editor-last1=Cresswell |editor-first1=Jamie |editor-last2=Wilson|editor-first2=Bryan}}</ref><ref>{{cite book |url=https://archive.org/details/DSM-5|title=DSM-5 |last=American Psychiatric Association}}</ref>\n\n {{See also|Thought reform in China}}\nThe Chinese term ''x\u01d0n\u0103o'' (\u6d17\u8166\uff0c"wash brain")<ref>{{cite web |url=http://www.mdbg.net/chindict/chindict.php?page=worddict&wdrst=0&wdqb=%E6%B4%97%E8%85%A6 |title=Word dictionary - \u6d17\u8166 - MDBG English to Chinese dictionary |website=mdbg.net}}</ref> was originally used to describe the coercive [[persuasion]] used under the [[Maoist]] government in China, which aimed to transform "reactionary" people into "right-thinking" members of the new Chinese social system.<ref>{{cite book |last=Taylor |first= Kathleen |author-link= Kathleen Taylor (biologist) |title=Brainwashing: The Science of Thought Control |url= https://books.google.com/books?id=D3tYeMLc4hQC |access-date=2010-07-02 |year=2006 |publisher=Oxford University Press |location=Oxford, UK |isbn=978-0-19-920478-6 |page=5}}</ref> The term [[pun]]ned on the [[Taoist]] custom of "cleansing / washing the heart / mind" (''x\u01d0x\u012bn''\uff0c\u6d17\u5fc3) before conducting ceremonies or entering holy places.<ref group=lower-alpha>'''Note:''' ''x\u012bn'' can mean "heart", "mind" or "centre" depending on context. For example, {{lang|zh-Latn|[[:zh:\u5fc3\u810f\u75c5|x\u012bn z\u00e0ng b\u00ecng]]}} means [[Cardiovascular disease]], but {{lang|zh-Latn|[[:zh:\u5fc3\u7406\u533b\u751f|x\u012bn l\u01d0 y\u012b sh\u0113ng]]}} means [[psychologist]], and {{lang|zh-Latn|[[:zh:\u5e02\u4e2d\u5fc3|sh\u00ec zh\u014dng x\u012bn]]}} means [[Central business district]].</ref>\n\nThe ''[[Oxford English Dictionary]]'' records the earliest known English-language usage of the word "brainwashing" in an article by a journalist [[Edward Hunter (U.S. journalist)|Edward Hunter]], in ''Miami News'', published on 24 September 1950. Hunter was an outspoken [[Anti-communism|anticommunist]] and was alleged to be a [[CIA]] agent working undercover as a journalist.<ref>{{cite book |last=Marks |first=John |author-link=John D. Marks |title=The Search for the Manchurian Candidate: The CIA and mind control |url=https://archive.org/details/searchformanchur00john |access-date=2008-12-30 |year=1979 |publisher=Times Books |location=New York |isbn=978-0-8129-0773-5 |chapter=Chapter 8. Brainwashing |chapter-url=http://www.druglibrary.org/schaffer/lsd/marks8.htm |quote=In September 1950, the ''[[The Miami News|Miami News]]'' published an article by Edward Hunter titled \u2018"Brain-Washing" Tactics Force Chinese into Ranks of Communist Party\u2019. It was the first printed use in any language of the term "brainwashing", Hunter, a CIA propaganda operator who worked undercover as a journalist, turned out a steady stream of books and articles on the subject. }}</ref> Hunter and others used the Chinese term to explain why, during the [[Korean War]] (1950-1953), some American [[prisoners of war]] (POWs) cooperated with their Chinese captors, and even in a few cases [[List of American and British defectors in the Korean War|defected to their side]].<ref>{{cite news |first=Michael |last=Browning |title=Was kidnapped Utah teen brainwashed? |work=[[Palm Beach Post]] |location=Palm Beach |issn=1528-5758 |date=2003-03-14 |quote=During the Korean War, captured American soldiers were subjected to prolonged interrogations and harangues by their captors, who often worked in relays and used the "good-cop, bad-cop" approach \u2013 alternating a brutal interrogator with a gentle one. It was all part of "Xi Nao" (''washing the brain''). The Chinese and Koreans were making valiant attempts to convert the captives to the communist way of thought.}}</ref> British radio operator [[Robert W. Ford]]<ref>{{cite book |author=Ford, R.C. |author-link=Robert W. Ford |title=Captured in Tibet |publisher=[[Oxford University Press]] |location=Oxford [Oxfordshire] |year=1990 |isbn=978-0-19-581570-2}}</ref><ref>{{cite book |author-link=Robert W. Ford |author=Ford, R.C. |title=Wind between the Worlds: Captured in Tibet |publisher=SLG Books |year=1997 |isbn=978-0-9617066-9-2 |url-access=registration |url=https://archive.org/details/windbetweenworld00ford }}</ref> and British army Colonel [[James Carne]] also claimed that the Chinese subjected them to brainwashing techniques during their imprisonment.<ref>{{cite news |newspaper=[[The New York Times]] |url=https://timesmachine.nytimes.com/timesmachine/1953/02/23/83712037.pdf |title=Red germ charges cite 2 U.S. Marines |date=23 February 1954 |access-date=16 February 2012}}</ref>\n\nThe U.S. military and government laid charges of brainwashing in an effort to undermine  confessions made by POWs to war crimes, including [[Allegations of biological warfare in the Korean War|biological warfare]].<ref>{{cite book |first1=Stephen|last1=Endicott|first2=Edward|last2=Hagerman|title=The United States and Biological Warfare: Secrets from the early Cold War |url=https://archive.org/details/unitedstatesbiol00endi  |url-access=registration  |publisher=Indiana University Press |year=1998|isbn=9780253334725}}</ref> After Chinese radio broadcasts claimed to quote [[Frank Schwable]], Chief of Staff of the [[1st Marine Aircraft Wing|First Marine Air Wing]] admitting to participating in germ warfare, United Nations commander Gen. [[Mark W. Clark]] asserted:<ref>{{cite news |newspaper=The New York Times |url=https://timesmachine.nytimes.com/timesmachine/1953/02/24/93602632.pdf |title=Clark denounces germ war charges |date=24 February 1953 |access-date=16 February 2012}}</ref>\n:'' Whether these statements ever passed the lips of these unfortunate men is doubtful. If they did, however, too familiar are the mind-annihilating methods of these Communists in extorting whatever words they want... The men themselves are not to blame, and they have my deepest sympathy for having been used in this abominable way.''\n\nBeginning in 1953, [[Robert Jay Lifton]] interviewed American servicemen who had been POWs during the [[Korean War]] as well as priests, students, and teachers who had been held in prison in China after 1951. In addition to interviews with 25 Americans and Europeans, Lifton interviewed 15 Chinese citizens who had fled after having been subjected to indoctrination in Chinese universities. (Lifton's 1961 book ''[[Thought Reform and the Psychology of Totalism: A Study of "Brainwashing" in China]]'', was based on this research.)<ref>{{cite book |author=Wilkes, A.L. |title=Knowledge in Minds |page=323 |publisher=Psychology Press |year=1998 |isbn=978-0-86377-439-3}}</ref> Lifton found that when the POWs returned to the United States their thinking soon returned to normal, contrary to the popular image of "brainwashing."<ref name="Home_by_Ship">{{cite journal |title=Home by Ship: Reaction patterns of American prisoners of war repatriated from North Korea |journal=American Journal of Psychiatry |date=April 1954 |first=Robert J. |last=Lifton |volume=110 |issue=10 |pages=732\u2013739 |pmid=13138750 |doi=10.1176/ajp.110.10.732}}</ref>\n\nIn 1956, after reexamining the concept of brainwashing following the Korean War, the U.S. Army published a report entitled ''Communist Interrogation, Indoctrination, and Exploitation of Prisoners of War'', which called brainwashing a "popular misconception". The report concludes that  "exhaustive research of several government agencies failed to reveal even one conclusively documented case of 'brainwashing' of an American prisoner of war in Korea."<ref>{{cite book |author=U.S Department of the Army |title=Communist Interrogation, Indoctrination, and Exploitation of Prisoners of War. |publisher=U.S. Government Printing Office |id=Pamphlet number 30-101 |date=15 May 1956 |location=Washington, DC |url = http://palmm.digital.flvc.org/islandora/object/fau%3A32574/datastream/OBJ/view/Communist_interrogation_indoctrination__and_exploitation_of_prisoners_of_war.pdf| pages=17, 51}}</ref>\n\n {{Main|Mind control in popular culture}}\n[[File:Sinatra and Harvey in Manchurian Candidate NYWTS.jpg|thumb|left|150px|[[Laurence Harvey]] and [[Frank Sinatra]] in ''[[The Manchurian Candidate (1962 film)|The Manchurian Candidate]]'']]\nIn [[George Orwell]]'s 1949 [[dystopian]] novel ''[[Nineteen Eighty-Four]]'', the main character is subjected to imprisonment, [[isolation to facilitate abuse|isolation]], and torture in order to conform his thoughts and emotions to the wishes of the rulers of Orwell's fictional future [[totalitarian]] society. Orwell's vision influenced [[Edward Hunter (journalist)|Hunter]] and is still reflected in the popular understanding of the concept of brainwashing.<ref>{{cite book |title=Psychiatry and Public Affairs |author=Leo H. Bartemeier |publisher=Aldine Transaction |date=1 August 2011 |page=246}}</ref><ref>{{cite book |title=Encyclopedia of New Religious Movements |author=Clarke, Peter |publisher=Routledge |date=1 March 2004 |page=76}}</ref>\n\nIn the 1950s, some American films were made that featured brainwashing of POWs, including [[The Rack (1956 film)|''The Rack'']], ''[[The Bamboo Prison]]'', ''[[Toward the Unknown]]'', and ''[[The Fearmakers]]''. ''[[Forbidden Area]]'' told the story of Soviet secret agents who had been brainwashed through [[classical conditioning]] by their own government so they wouldn't reveal their identities. In 1962, [[The Manchurian Candidate (1962 film)|''The Manchurian Candidate'']] (based on the 1959 novel by [[Richard Condon]]) "put brainwashing front and center" by featuring a plot by the Soviet government to take over the United States by using a brainwashed [[sleeper agent]] for political assassination.<ref>{{cite book |title=Screen Enemies of the American Way: Political paranoia about Nazis, Communists, Saboteurs, Terrorists and Body Snatching Aliens in Film and Television |author=Sherman, Fraser A. |publisher=McFarland |date=13 December 2010}}</ref><ref>{{cite book |title=Brainwashing: A study in Cold War demonology |last=Seed |first=David |year=2004 |publisher=Kent State University Press |isbn=978-0-87338-813-9 |page=[https://archive.org/details/brainwashingfict0000seed/page/51 51] |url=https://archive.org/details/brainwashingfict0000seed/page/51 }}</ref><ref>{{cite web |url=http://www.listal.com/list/mind-control-movies-tv |title=Mind-control movies and TV |author=Steven a.k.a. Superant |website=listal.com |access-date=12 March 2016}}</ref>  The concept of brainwashing became popularly associated with the research of Russian psychologist [[Ivan Pavlov]], which mostly involved dogs as subjects.<ref>{{cite book |title=Judicial Policy Making and the Modern State: How the courts reformed America's prisons |author1=Feeley, Malcolm M. |author2=Rubin, Edward L. |publisher=Cambridge University Press |date=28 March 2000 |page=268}}</ref> In [[The Manchurian Candidate (1962 film)|''The Manchurian Candidate'']], the head brainwasher is "Dr. Yen Lo, of the Pavlov Institute."<ref>{{cite book |title=Asian Diaspora and East-West Modernity |author=Ma, Sheng-mei |publisher=Purdue University Press |year=2012 |page=129}}</ref>\n\nThe [[science fiction]] stories of [[Cordwainer Smith]] (pen name of Paul Myron Anthony Linebarger (1913-1966), a US Army officer who specialized in [[military intelligence]] and [[psychological warfare]] during the Second World War and the Korean War) depict brainwashing to remove memories of traumatic events as a normal and benign part of future medical practice.<ref>{{cite book |author1=Wolfe, Gary K. |author2=Williams, Carol T. |contribution=The Majesty of Kindness: The dialectic of Cordwainer Smith |title=Voices for the Future: Essays on major science fiction writers |volume=3 |editor=Clareson, Thomas D. |publisher=Popular Press |year=1983 |pages=53\u201372}}</ref>  In 1971, a film "A Clockwork Orange" positions institutional brainwashing as an option for violent convicts looking to shorten their sentences and in 1997's film "Conspiracy Theory," a mentally unstable, government-brainwashed assassin seeks to prove that some very powerful people have been tampering with his mind.<ref>{{Cite web|date=2006-05-10|title=How Brainwashing Works|url=https://science.howstuffworks.com/life/inside-the-mind/human-brain/brainwashing.htm|access-date=2021-09-13|website=HowStuffWorks|language=en}}</ref> \n\nA comedy movie to include brainwashing is the 1985 film [[Volunteers (1985 film)|Volunteers]] with [[Tom Hanks]] and [[John Candy]], where the latter's character is brainwashed by Communist guerillas while serving in the [[Peace Corps]].\n\nMind control remains an important theme in science fiction.  A subgenre is ''corporate mind control'', in which a future society is run by one or more business [[corporations]] that dominate society using [[advertising]] and [[mass media]] to control the population's thoughts and feelings.<ref>{{cite book |author=Schelde, Per |title=Androids, Humanoids, and other Science Fiction Monsters: Science and soul in science fiction films |url=https://archive.org/details/androidshumanoid00sche |url-access=limited |publisher=NYU Press |date=1 July 1994 |pages=[https://archive.org/details/androidshumanoid00sche/page/n180 169]\u2013175|isbn=9780585321172 }}</ref>  Terry O'Brien commented: "Mind control is such a powerful image that if [[hypnotism]] did not exist, then something similar would have to have been invented: The plot device is too useful for any writer to ignore. The fear of mind control is equally as powerful an image."<ref>{{cite book |author=O'Brien, Terry |title=The Greenwood Encyclopedia of Science Fiction and Fantasy: Themes, Works, and Wonders |volume=1 |editor=Westfahl, Gary |publisher=Greenwood Publishing Group |year=2005}}</ref>\n\n [[File:Hearst-hibernia-yell.jpg|200 px|alt=|thumb|Bank robbery by [[Patty Hearst]] and [[Symbionese Liberation Army]] members<ref name="Famous Pictures Magazine">{{cite web |date= May 14, 2013 |url= http://www.famouspictures.org/patty-hearst/ |title= Patty Hearst |publisher= Famous Pictures Magazine |access-date= January 21, 2016 |last= Lucas |first=Dean}}</ref>]]\nThe concept of brainwashing has been raised in the defense of criminal charges.  It has also been raised in child custody cases.<ref>[[Richard Warshak|Warshak, R. A.]] (2010). ''Divorce Poison: How to Protect Your Family from Bad-mouthing and Brainwashing''. New York: Harper Collins.</ref><ref>Richardson, James T. ''Regulating Religion: Case Studies from Around the Globe'', Kluwer Academic/Plenum Publishers 2004, p. 16, {{ISBN|978-0-306-47887-1}}.</ref>  The 1969 to 1971 case of [[Charles Manson]], who was said to have brainwashed his followers to commit murder and other crimes, brought the issue to renewed public attention.<ref>''Minds on Trial: Great Cases in Law and Psychology'', by Charles Patrick Ewing, Joseph T. McCann pp. 34\u201336</ref><ref>Shifting the Blame: How Victimization Became a Criminal Defense, Saundra Davis Westervelt, Rutgers University Press, 1998. page 158</ref>\n\nIn 1974, [[Patty Hearst]], a member of the wealthy [[William Randolph Hearst|Hearst family]], was [[Kidnapping|kidnapped]] by the [[Symbionese Liberation Army]], a left-wing militant organization. After several weeks of captivity she agreed to join the group and took part in their activities.  In 1975, she was arrested and charged with bank robbery and use of a gun in committing a felony.  Her attorney, [[F. Lee Bailey]], argued in her trial that she should not be held responsible for her actions since her treatment by her captors was the equivalent of the alleged brainwashing of Korean War POWs (see also [[Diminished responsibility]]).<ref name="Regreligion">Regulating Religion: Case Studies from Around the Globe, James T. Richardson, Springer Science & Business Media, 6 December 2012, page 518</ref>  Bailey developed his case in conjunction with psychiatrist [[Louis Jolyon West]] and psychologist [[Margaret Singer]].  They had both studied the experiences of Korean War POWs. (In 1996 Singer published her theories in her best-selling book ''[[Cults in Our Midst]]''.<ref name="refocus.org">[http://www.refocus.org/singerne.html ''Cults in Our Midst: The Continuing Fight Against Their Hidden Menace''] {{webarchive|url=https://web.archive.org/web/20150202034934/http://www.refocus.org/singerne.html|date=2 February 2015}}, Margaret Thaler Singer, Jossey-Bass, publisher, April 2003, {{ISBN|0-7879-6741-6}}</ref><ref name="clarke">{{Cite book|last1=Clarke|first1=Peter|url=https://books.google.com/books?id=DouBAgAAQBAJ|title=Encyclopedia of New Religious Movements|last2=Clarke|first2=Reader in Modern History Fellow Peter|date=March 2004|isbn=9781134499700}}</ref><ref>{{Cite news|last=Hilts|first=Philip J.|date=9 January 1999|title=Louis J. West, 74, Psychiatrist Who Studied Extremes, Dies|newspaper=The New York Times|url=https://www.nytimes.com/1999/01/09/us/louis-j-west-74-psychiatrist-who-studied-extremes-dies.html|access-date=31 December 2016}}</ref>)   Despite this defense Hearst was found guilty.<ref name="Regreligion"/>\n\nIn 1990 [[Steven Fishman]], who was a member of the [[Church of Scientology]], was charged with [[mail fraud]] for conducting a scheme to sue large corporations via conspiring with minority stockholders in shareholder class action lawsuits. Afterwards, he would sign settlements that left those stockholders empty-handed. Fishman's attorneys notified the court that they intended to rely on an [[insanity defense]], using the theories of brainwashing and the expert witnesses of Singer and [[Richard Ofshe]] to claim that Scientology had practiced brainwashing on him which left him unsuitable to make independent decisions. The court ruled that the use of brainwashing theories is inadmissible in expert witnesses, citing the [[Frye standard]], which states that scientific theories utilized by expert witnesses must be generally accepted in their respective fields.<ref>{{cite news|title=United States v. Fishman (1990)|url=https://law.justia.com/cases/federal/district-courts/FSupp/743/713/2593631/|newspaper=Justia Law}}</ref>\n\nIn 2003, the brainwashing defense was used unsuccessfully in the defense of [[Lee Boyd Malvo]], who was charged with murder for his part in the [[D.C. sniper attacks]].<ref>Mental Condition Defences and the Criminal Justice System: Perspectives from Law and Medicine, Ben Livings, Alan Reed, Nicola Wake, Cambridge Scholars Publishing, 27 February 2015, Page 98</ref><ref name="Oldenburg">Oldenburg, Don (2003-11-21). [http://www.crimlaw.org/defbrief269.html "Stressed to Kill: The Defense of Brainwashing; Sniper Suspect's Claim Triggers More Debate"] {{webarchive|url=https://web.archive.org/web/20110501144721/http://www.crimlaw.org/defbrief269.html|date=1 May 2011}}, ''[[The Washington Post]]'', reproduced in ''Defence Brief'', issue 269, published by Steven Skurka & Associates</ref>\n\nSome legal scholars have argued that the brainwashing defense undermines the law's  fundamental premise of [[free will]].<ref>Freedom and Criminal Responsibility in American Legal Thought, Thomas Andrew Green, Cambridge University Press, 27 Oct 2014, page 391</ref><ref>LaFave's Criminal Law, 5th (Hornbook Series), Wayne LaFave, West Academic, 18 March 2010, pages 208-210</ref> In 2003, forensic psychologist [[Dick Anthony]] said that "no reasonable person would question that there are situations where people can be influenced against their best interests, but those arguments are evaluated on the basis of fact, not bogus expert testimony."<ref name="Oldenburg"/>\n\n {{Main|Anti-cult movement}}\n\n[[File:Philip_Zimbardo_(cropped).jpg|thumb|left|150px|[[Phillip Zimbardo]]]]\nIn the 1970s and 1980s, the anti-cult movement applied the concept of brainwashing to explain seemingly sudden and dramatic [[religious conversion]]s to various [[new religious movement]]s (NRMs) and other groups that they considered [[cults]].<ref>{{cite web |first=J. Gordon |last=Melton |author-link=J. Gordon Melton |title=Brainwashing and the Cults: The Rise and Fall of a Theory |url=http://www.cesnur.org/testi/melton.htm |publisher=CESNUR: Center for Studies on New Religions |date=1999-12-10 |access-date=2009-06-15 |quote=In the United States at the end of the 1970s, brainwashing emerged as a popular theoretical construct around which to understand what appeared to be a sudden rise of new and unfamiliar religious movements during the previous decade, especially those associated with the hippie street-people phenomenon.}}</ref><ref name="BromleyEncy">{{cite book |chapter=Brainwashing |last=Bromley |first= David G. |year=1998 |pages=61\u201362 |title=Encyclopedia of Religion and Society |editor=William H. Swatos Jr. |publisher=AltaMira |location=Walnut Creek, CA |isbn=978-0-7619-8956-1}}</ref><ref>Barker, Eileen: ''New Religious Movements: A Practical Introduction''. London: Her Majesty's Stationery office, 1989.</ref>  News media reports tended to support the brainwashing view<ref name="Wright">{{cite journal |author=Wright, Stewart A. |year=1997 |title=Media Coverage of Unconventional Religion: Any 'Good News' for Minority Faiths? |journal=Review of Religious Research |volume=39 |issue=2 |pages=101\u2013115 |doi=10.2307/3512176 |jstor=3512176}}</ref> and [[social scientists]] sympathetic to the anti-cult movement, who were usually [[psychologists]], developed revised models of mind control.<ref name="BromleyEncy" /> While some psychologists were receptive to the concept, sociologists were for the most part skeptical of its ability to explain conversion to NRMs.<ref name="BarkerAReview">{{cite journal |author=Barker, Eileen |year=1986 |title=Religious Movements: Cult and Anti-Cult Since Jonestown |journal=Annual Review of Sociology |volume=12 |pages=329\u2013346 |doi=10.1146/annurev.so.12.080186.001553}}</ref>\n\n[[Philip Zimbardo]] defined mind control as "the process by which individual or collective freedom of choice and action is compromised by agents or agencies that modify or distort perception, motivation, affect, cognition or behavioral outcomes,"<ref name="Zimbardo 2002">{{cite journal |last=Zimbardo |first=Philip G. |author-link=Philip Zimbardo |date=November 2002 |title=Mind Control: Psychological Reality or Mindless Rhetoric? |journal=Monitor on Psychology |url=http://www.icsahome.com/articles/mind-control-zimbardo |access-date=2016-06-02 |quote=Mind control is the process by which individual or collective freedom of choice and action is compromised by agents or agencies that modify or distort perception, motivation, affect, cognition or behavioral outcomes. It is neither magical nor mystical, but a process that involves a set of basic social psychological principles. Conformity, compliance, persuasion, dissonance, reactance, guilt and fear arousal, modeling and identification are some of the staple social influence ingredients well studied in psychological experiments and field studies. In some combinations, they create a powerful crucible of extreme mental and behavioral [[Psychological manipulation|manipulation]] when synthesized with several other real-world factors, such as charismatic, authoritarian leaders, dominant ideologies, social isolation, physical debilitation, induced phobias, and extreme threats or promised rewards that are typically deceptively orchestrated, over an extended time period in settings where they are applied intensively. A body of social science evidence shows that when systematically practiced by state-sanctioned police, military or destructive cults, mind control can induce false confessions, create converts who willingly torture or kill 'invented enemies,' and engage indoctrinated members to work tirelessly, give up their money\u2014and even their lives\u2014for 'the cause.' |archive-date=4 July 2016 |archive-url=https://web.archive.org/web/20160704120313/http://www.icsahome.com/articles/mind-control-zimbardo |url-status=dead }}</ref> and he suggested that any human being is susceptible to such manipulation.<ref name="Zimbardo 1997 14">{{cite journal |last=Zimbardo |first=P |author-link=Philip Zimbardo |url=http://www.csj.org/studyindex/studycult/study_zimbar.htm |page=14 |title=What messages are behind today's cults? |journal=Monitor on Psychology |year=1997 |access-date=1 October 2009 |archive-date=2 May 1998 |archive-url=https://web.archive.org/web/19980502070642/http://csj.org/studyindex/studycult/study_zimbar.htm |url-status=dead }}</ref>\n\n[[Benjamin Zablocki]] asserted that brainwashing is not "a process that is directly observable,"<ref name="linfran">{{cite web |last1=Allen |first1=Charlotte |title=Brainwashed! Scholars of Cults Accuse Each Other of Bad Faith |url=http://linguafranca.com/9812/allen.html |archive-url=https://web.archive.org/web/20001203192600/http://linguafranca.com/9812/allen.html |website=Lingua Franca |archive-date=2000-12-03 |date=December 1998 |publisher=linguafranca.com |access-date=2014-06-16}}</ref> and that the "real sociological issue" is whether "brainwashing occurs frequently enough to be considered an important social problem."<ref name="Zablocki1997" />  According to Zablocki other scholars commonly mistook brainwashing for both a recruiting and a retaining process, when it is merely the latter.<ref name="Zablocki2001">{{cite book |last=Zablocki|first=Benjamin |title=Misunderstanding Cults: Searching for Objectivity in a Controversial Field |year=2001 |publisher=U of Toronto Press |isbn=978-0-8020-8188-9 |page=176}}</ref> He also asserted that the number of people who attest to brainwashing in interviews (performed in accordance with guidelines of the [[National Institute of Mental Health]] and [[National Science Foundation]]) is too large to result from anything other than a genuine phenomenon.<ref name="zablocki-p194-201">{{cite book |last=Zablocki|first=Benjamin |title=Misunderstanding Cults: Searching for Objectivity in a Controversial Field |year=2001 |publisher=U of Toronto Press |isbn=978-0-8020-8188-9 |pages=194\u2013201}}</ref>  Zablocki also pointed out that in the two most prestigious journals dedicated to the [[sociology of religion]] there have been no articles "supporting the brainwashing perspective," while over one hundred such articles have been published in other journals "marginal to the field."<ref name="Zablocki1998">{{cite journal |title=TReply to Bromley |journal=Nova Religio |date=April 1998 |first=Benjamin. |last=Zablocki |volume=1 |issue=2 |pages=267\u2013271 |doi=10.1525/nr.1998.1.2.267}}</ref> He concluded that the concept of brainwashing had been unfairly [[blacklisted]].<ref name="Melton" /><ref name="Zablocki1997">{{cite journal |journal=Nova Religio |date=October 1997 |first=Benjamin. |last=Zablocki |volume=1 |issue=1 |pages=96\u2013121 |doi=10.1525/nr.1997.1.1.96|title=The Blacklisting of a Concept: The Strange History of the Brainwashing Conjecture in the Sociology of Religion }}</ref><ref name="Zablocki1998" /><ref>Phil Zuckerman. Invitation to the Sociology of Religion. Psychology Press, 24 July 2003 p. 28</ref>\n\n[[Eileen Barker]] criticized the concept of mind control because it functioned to justify costly interventions such as [[deprogramming]] or exit counseling.<ref name="Rusher">[https://web.archive.org/web/20050415093632/http://www.findarticles.com/p/articles/mi_m1282/is_v38/ai_4580948 Review], [[William Rusher]], ''[[National Review]]'', 19 December 1986.</ref> She has also criticized some mental health professionals, including Singer, for accepting expert witness jobs in court cases involving NRMs.<ref name="BarkerJoke">{{cite journal |author=Barker, Eileen |year=1995 |title=The Scientific Study of Religion? You Must Be Joking! |journal=Journal for the Scientific Study of Religion |volume=34 |issue=3 |pages=287\u2013310 |doi=10.2307/1386880 |jstor=1386880}}</ref> Her 1984 book, ''[[The Making of a Moonie: Choice or Brainwashing?]]''<ref>[[Eileen Barker]], ''The Making of a Moonie: Choice or Brainwashing?'', [[Blackwell's|Blackwell Publishers]], Oxford, United Kingdom, {{ISBN|0-631-13246-5}}.</ref> describes the religious conversion process to the [[Unification Church]] (whose members are sometimes informally referred to as ''[[Moonie (nickname)|Moonies]]''), which had been one of the best known groups said to practice brainwashing.<ref name="Barker2012">[http://religion.blogs.cnn.com/2012/09/03/my-take-moons-death-marks-end-of-an-era/ Moon\u2019s death marks end of an era], [[Eileen Barker]], [[CNN]], 3 September 2012, Although Moon is likely to be remembered for all these things \u2013 mass weddings, accusations of brainwashing, political intrigue and enormous wealth \u2013 he should also be remembered as creating what was arguably one of the most comprehensive and innovative theologies embraced by a new religion of the period.</ref><ref name="usatoday2012-09-02a">{{cite news|url=http://usatoday30.usatoday.com/news/world/story/2012-09-02/unification-church-rev-moon-dies/57537454/1|title=Unification Church founder Rev. Sun Myung Moon dies at 92|author=Hyung-Jin Kim|work=USA Today|issn=0734-7456|date=2 September 2012|access-date=2 September 2012|quote=The Rev. Sun Myung Moon was a self-proclaimed messiah who built a global business empire. He called both North Korean leaders and American presidents his friends, but spent time in prisons in both countries. His followers around the world cherished him, while his detractors accused him of brainwashing recruits and extracting money from worshippers.|archive-date=29 September 2012|archive-url=https://web.archive.org/web/20120929230011/http://usatoday30.usatoday.com/news/world/story/2012-09-02/unification-church-rev-moon-dies/57537454/1|url-status=dead}}</ref> Barker spent close to seven years studying Unification Church members and wrote that she rejects the "brainwashing" theory, because it explains neither the many people who attended a recruitment meeting and did not become members, nor the voluntary disaffiliation of members.<ref name="Rusher" /><ref>[https://web.archive.org/web/20060618211708/http://web.uni-marburg.de/religionswissenschaft/journal/diskus/chryssides.html New Religious Movements - Some Problems of Definition] [[George Chryssides]], ''Diskus'', 1997.</ref><ref>[http://faculty.arec.umd.edu/cmcausland/RALi/The%20Market%20for%20Martyrs.pdf The Market for Martyrs] {{webarchive|url=https://web.archive.org/web/20120111212356/http://faculty.arec.umd.edu/cmcausland/RALi/The%20Market%20for%20Martyrs.pdf |date=11 January 2012 }}, [[Laurence Iannaccone]], [[George Mason University]], 2006, "One of the most comprehensive and influential studies was The Making of a Moonie: Choice or Brainwashing? by Eileen Barker (1984). Barker could find no evidence that Moonie recruits were ever kidnapped, confined, or coerced. Participants at Moonie retreats were not [[deprived of sleep]]; the lectures were not "trance-inducing" and there was not much chanting, no drugs or alcohol, and little that could be termed "frenzy" or "ecstatic" experience. People were free to leave, and leave they did. Barker\u2019s extensive enumerations showed that among the recruits who went so far as to attend two-day retreats (claimed to beMoonie\u2019s most effective means of "brainwashing"), fewer than 25% joined the group for more than a week and only 5% remained full-time members one year later. And, of course, most contacts dropped out before attending a retreat. Of all those who visited a Moonie centre at least once, not one in two-hundred remained in the movement two years later. With failure rates exceeding 99.5%, it comes as no surprise that full-time Moonie membership in the U.S. never exceeded a few thousand. And this was one of the most New Religious Movements of the era!"</ref><ref>Oakes, Len "By far the best study of the conversion process is Eileen Barker\u2019s The Making of a Moonie [...]" from ''Prophetic Charisma: The Psychology of Revolutionary Religious Personalities'', 1997, {{ISBN|0-8156-0398-3}}</ref><ref>Storr, Anthony ''Feet of clay: a study of gurus'' 1996 {{ISBN|0-684-83495-2}}</ref>\n\n[[James Richardson (sociologist)|James Richardson]] observed that if the new religious movements had access to powerful brainwashing techniques, one would expect that they would have high growth rates, yet in fact most have not had notable success in recruiting or retaining members<ref name="Richardson1985">{{cite journal |title=The active vs. passive convert: paradigm conflict in conversion/recruitment research |journal=Journal for the Scientific Study of Religion |date=June 1985 |first=James T. |last=Richardson |volume=24 |issue=2 |pages=163\u2013179 |doi=10.2307/1386340 |jstor=1386340}}</ref> For this and other reasons, sociologists of religion including [[David G. Bromley|David Bromley]] and [[Anson Shupe]] consider the idea that "cults" are brainwashing American youth to be "implausible."<ref name="brain_wash">{{cite web|url=http://www.religioustolerance.org/brain_wa.htm|title=Brainwashing by Religious Cults|work=religioustolerance.org}}</ref> [[Thomas Robbins (sociologist)|Thomas Robbins]], [[Massimo Introvigne]], [[Lorne Dawson]], [[Gordon Melton]], [[Marc Galanter (psychiatrist)|Marc Galanter]], and [[Saul Levine]], amongst other scholars researching NRMs, have argued and established to the satisfaction of courts, relevant professional associations and scientific communities that there exists no generally accepted scientific theory, based upon methodologically sound research, that supports the concept of brainwashing.<ref>Richardson, James T. 2009. "Religion and The Law" in The Oxford Handbook of the Sociology of Religion. Peter Clarke. (ed) Oxford Handbooks Online. p. 426</ref>\n\nIn 1999 [[forensic psychologist]] [[Dick Anthony]] criticized another adherent to this view, [[Jean-Marie Abgrall]], for allegedly employing a [[pseudo-scientific]] approach and lacking any evidence that anyone's [[worldview]] was substantially changed by these coercive methods. He claimed that the concept and the fear surrounding it was used as a tool for the anti-cult movement to rationalize the persecution of minority religious groups.<ref>{{cite journal | doi=10.1023/A:1022081411463 | volume=12 | issue=4 | title=Pseudoscience and Minority Religions: An Evaluation of the Brainwashing Theories of Jean-Marie Abgrall | journal=Social Justice Research | pages=421\u2013456|year = 1999|last1 = Anthony|first1 = Dick| s2cid=140454555 }}</ref>\n\nIn 2016, Israeli anthropologist of religion and fellow at the [[Van Leer Jerusalem Institute]] Adam Klin-Oron said about then-proposed "anti-cult" legislation: \n{{Quote|In the 1980s there was a wave of \u2018brainwashing\u2019 claims, and then parliaments around the world examined the issue, courts around the world examined the issue, and reached a clear ruling: That there is no such thing as cults\u2026that the people making these claims are often not experts on the issue. And in the end courts, including in Israel, rejected expert witnesses who claimed there is "brainwashing."<ref>[http://www.timesofisrael.com/will-israels-first-anti-cult-legislation-harm-religious-freedom], ''[[Times of Israel]]<nowiki>''</nowiki>''</ref>''}}\n\n [[File:ProjectMKULTRA Senate Report.pdf|thumb|1977 United States Senate report on [[Project MKUltra]], the [[Central Intelligence Agency]]'s program of research into brainwashing]]\n\n {{Main|APA Task Force on Deceptive and Indirect Methods of Persuasion and Control}}\n\nIn 1983, the [[American Psychological Association]] (APA) asked Singer to chair a [[taskforce]] called the APA Task Force on Deceptive and Indirect Techniques of Persuasion and Control (DIMPAC) to investigate whether brainwashing or coercive persuasion did indeed play a role in recruitment by NRMs.\n<ref>\nAs archived at http://www.cesnur.org/testi/DIMPAC.htm, retrieved 2008-06-23\n</ref> It came to the following conclusion:<ref>\n{{cite web\n| url         = http://www.cesnur.org/testi/APA.htm\n| title       = Memorandum\n| access-date  = 2008-11-18\n| author      = American Psychological Association Board of Social and Ethical Responsibility for Psychology (BSERP)\n| date        = 1987-05-11\n| work        = CESNUR: APA Memo of 1987 with Enclosures\n| publisher   = CESNUR Center for Studies on New Religions\n| quote       = BSERP requests that Task Force members not distribute or publicize the report without indicating that the report was unacceptable to the Board.\n}}\n</ref>\n\n<blockquote>\n''Cults and [[large group awareness training]]s have generated considerable controversy because of their widespread use of deceptive and indirect techniques of persuasion and control. These techniques can compromise individual freedom, and their use has resulted in serious harm to thousands of individuals and families. This report reviews the literature on this subject, proposes a new way of conceptualizing influence techniques, explores the ethical ramifications of deceptive and indirect techniques of persuasion and control, and makes recommendations addressing the problems described in the report.''\n</blockquote>\n\nOn 11 May 1987, the APA's Board of Social and Ethical Responsibility for Psychology (BSERP) rejected the DIMPAC report because the report "lacks the scientific rigor and evenhanded critical approach necessary for APA imprimatur", and concluded that "after much consideration, BSERP does not believe that we have sufficient information available to guide us in taking a position on this issue."<ref>{{cite web |url=http://www.cesnur.org/testi/APA.htm |title=Memorandum |access-date=2008-11-18 |author=American Psychological Association Board of Social and Ethical Responsibility for Psychology (BSERP) |date=1987-05-11 |work=CESNUR: APA Memo of 1987 with Enclosures |publisher=CESNUR Center for Studies on New Religion |quote=BSERP thanks the Task Force on Deceptive and Indirect Methods of Persuasion and Control for its service but is unable to accept the report of the Task Force. In general, the report lacks the scientific rigor and evenhanded critical approach necessary for APA imprimatur.}}</ref>\n\n {{Main|Project MKUltra}}\nFor 20 years starting in the early 1950s, the [[United States Central Intelligence Agency]] (CIA) and the [[United States Department of Defense]] conducted secret research, including [[Project MKUltra]], in an attempt to develop practical brainwashing techniques; These experiments ranged "from [[electroshock]] to high doses of [[Lysergic acid diethylamide|LSD]]".<ref name=":0">{{Cite news|url=https://www.npr.org/2019/09/09/758989641/the-cias-secret-quest-for-mind-control-torture-lsd-and-a-poisoner-in-chief|title = The CIA's Secret Quest for Mind Control: Torture, LSD and A 'Poisoner in Chief'|newspaper = NPR.org}}</ref> The full extent of the results are unknown. The director [[Sidney Gottlieb]] and his team, however, were apparently able to "blast away the existing mind" of a human being by using torture techniques<ref name=":0" /> \u2013 reprogramming, however, in terms of finding "a way to insert a new mind into that resulting void"<ref name=":0" /> was not so successful at least at the time.<ref name="Anthony">{{cite journal |author=Anthony, Dick |year=1999 |title=Pseudoscience and Minority Religions: An evaluation of the brainwashing theories of Jean-Marie |journal=Social Justice Research |volume=12 |issue=4 |pages=421\u2013456 |doi=10.1023/A:1022081411463|s2cid=140454555 }}</ref><ref>{{cite web|url=http://www.eh.doe.gov/ohre/roadmap/achre/chap3_4.html |title=Chapter 3, part 4: Supreme Court Dissents Invoke the Nuremberg Code: CIA and DOD Human Subjects Research Scandals |work=Advisory Committee on Human Radiation Experiments Final Report |access-date=24 August 2005 |url-status=dead |archive-url=https://web.archive.org/web/20041109061412/http://www.eh.doe.gov/ohre/roadmap/achre/chap3_4.html |archive-date=9 November 2004 }} "MKUltra, began in 1950 and was motivated largely in response to alleged Soviet, Chinese, and North Korean uses of mind-control techniques on U.S. prisoners of war in Korea."</ref> Some scholars such as the controversial psychiatrist [[Colin A. Ross]] claim, however, that the CIA was successful in creating programmable so-called "''[[The Manchurian Candidate|Manchurian Candidates]]"'' even at the time.<ref>{{Cite journal|url=https://doi.org/10.1300/J229v02n03_08|doi = 10.1300/J229v02n03_08|title = Book Review|journal = Journal of Trauma & Dissociation|year = 2001|volume = 2|issue = 3|pages = 123\u2013128|s2cid = 220439052}}</ref> The CIA experiments using various psychedelic drugs such as LSD and [[Mescaline]] drew from previous [[Nazi human experimentation]].<ref>The Search for the Manchurian Candidate: The CIA and Mind Control: By John Marks.  P 93 (c)1979 by John Marks Published by Times Books {{ISBN|0-8129-0773-6}}</ref>\n\nA bipartisan Senate Armed Services Committee report, released in part in December 2008 and in full in April 2009, reported that US military trainers who came to [[Guant\u00e1namo Bay]] in December 2002 had based an interrogation class on a chart copied from a 1957 Air Force study of "Chinese Communist"  brainwashing techniques. The report showed how the Secretary of Defense's 2002 authorization of the aggressive techniques at Guant\u00e1namo led to their use in [[Afghanistan]] and in [[Iraq]], including at [[Abu Ghraib]].<ref>{{cite news |last=Chaddock |first=Gail Russell |url=https://www.csmonitor.com/USA/Politics/2009/0422/report-says-top-officials-set-tone-for-detainee-abuse |title=Report says top officials set tone for detainee abuse |work=[[The Christian Science Monitor]] |date=April 22, 2009 |access-date=2020-01-03 }}</ref>\n\n [[File:Joost-a-m-meerloo.jpg|thumb|right|150px|[[Joost Meerloo]]]]\n[[Joost Meerloo]], a Dutch psychiatrist, was an early proponent of the concept of brainwashing. ("Menticide" is a [[neologism]] coined by him meaning: "killing of the mind.") Meerloo's view was influenced by his experiences during the German occupation of his country and his work with the Dutch government and the American military in the [[interrogation]] of accused [[Nazi war criminals]]. He later emigrated to the United States and taught at [[Columbia University]].<ref>The Oxford Handbook of Propaganda Studies, Jonathan Auerbach, Russ Castronovo, Oxford University Press, 2014, page 114</ref> His best-selling 1956 book, ''The Rape of the Mind'', concludes by saying: \n:''The modern techniques of brainwashing and menticide\u2014those perversions of psychology\u2014can bring almost any man into submission and surrender. Many of the victims of thought control, brainwashing, and menticide that we have talked about were strong men whose minds and wills were broken and degraded. But although the totalitarians use their knowledge of the mind for vicious and unscrupulous purposes, our democratic society can and must use its knowledge to help man to grow, to guard his freedom, and to understand himself.'' <ref>*{{cite web |author= Meerloo, Joost |url=http://www.lermanet.com/scientology/mc-ch1.html |title=The Rape of the Mind: The Psychology of Thought Control, Menticide, and Brainwashing |year=1956 |publisher=World Publishing Company|author-link=Joost Meerloo }}</ref>\n\nRussian historian [[Daniel Romanovsky]], who interviewed survivors and eyewitnesses in the 1970s, reported on what he called "[[Nazi]] brainwashing" of the people of [[Belarus]] by the occupying Germans during the [[Second World War]], which took place through both mass [[propaganda]] and intense re-education, especially in schools. Romanovsky noted that very soon most people had adopted the Nazi view that the Jews were an inferior race and were closely tied to the [[Soviet]] government, views that had not been at all common before the German occupation.<ref>''Nazi Europe and the Final Solution'', David Bankier, Israel Gutman, Berghahn Books, 2009, page 282-285.</ref><ref>Gray Zones: Ambiguity and Compromise in the Holocaust and its Aftermath, Jonathan Petropoulos, John Roth, Berghahn Books, 15 July 2005, page 209</ref><ref>The Minsk Ghetto 1941-1943: Jewish Resistance and Soviet Internationalism, Barbara Epstein, University of California Press, 2008, page 295</ref><ref>Bringing the Dark Past to Light: The Reception of the Holocaust in Postcommunist Europe, John-Paul Himka, Joanna Beata Michlic, University of Nebraska Press, 1 July 2013, pages 74, 78</ref><ref>{{cite web|url=http://www.angelfire.com/sc3/soviet_jews_exodus/English/Interview_s/InterviewRomanovsky.shtml |title=Interview |publisher=Angelfire.com |access-date=2019-08-05}}</ref><ref>*{{citation|chapter-url=https://books.google.com/books?id=oU6WielZ_VoC&pg=PA276|chapter=The Soviet Person as a Bystander of the Holocaust: The case of eastern Belorussia|first=Daniel|last=Romanovsky|page=276|title=Nazi Europe and the Final Solution|editor-first=David|editor-last=Bankier|editor2-first=Israel|editor2-last=Gutman|year=2009|publisher=Berghahn Books|isbn=9781845454104}}\n*{{cite journal|title=The Holocaust in the Eyes of Homo Sovieticus: A Survey Based on Northeastern Belorussia and Northwestern Russia|journal=Holocaust and Genocide Studies|year=1999|volume=13|issue=3|pages=355\u2013382|doi=10.1093/hgs/13.3.355|last1=Romanovsky|first1=D.}}\n*{{citation|first=Daniel|last=Romanovsky|chapter=Soviet Jews Under Nazi Occupation in Northeastern Belarus and Western Russia|title=Bitter Legacy: Confronting the Holocaust in the USSR|editor-first=Zvi|editor-last=Gitelman|year=1997|publisher=Indiana University Press|page=241}}</ref>\n\n[[Italy]] has had controversy over the concept of ''[[plagio]]'', a crime consisting in an absolute psychological\u2014and eventually physical\u2014domination of a person. The effect is said to be the annihilation of the subject's [[freedom]] and [[self-determination]] and the consequent negation of his or her [[personality]]. The crime of plagio has rarely been prosecuted in Italy, and only one person was ever convicted. In 1981, an Italian court found that the concept is imprecise, lacks coherence and is liable to arbitrary application.<ref>Alessandro Usai "Profili penali dei condizionamenti mentali, Milano, 1996 {{ISBN|88-14-06071-1}}.</ref>\n\nRecent scientific book publications in the field of the [[mental disorder]] "[[dissociative identity disorder]]" (DID) mention [[torture]]-based brainwashing by criminal networks and malevolent actors as a deliberate means to create multiple "programmable" personalities in a person to exploit this individual for sexual and financial reasons.<ref>{{Citation|last=Schwartz|first=Rachel Wingfield|title="An evil cradling"? Cult practices and the manipulation of attachment needs in ritual abuse|date=2018-03-22|url=http://dx.doi.org/10.4324/9780429479700-2|work=Ritual Abuse and Mind Control|pages=39\u201355|publisher=Routledge|doi=10.4324/9780429479700-2|isbn=978-0-429-47970-0|access-date=2021-07-11}}</ref><ref>{{Citation|last=Miller|first=Alison|chapter=Becoming Yourself|date=2018-05-11|chapter-url=http://dx.doi.org/10.4324/9780429472251-21|pages=347\u2013370|publisher=Routledge|doi=10.4324/9780429472251-21|isbn=978-0-429-47225-1|access-date=2021-07-11}}</ref><ref>{{Cite book|last=Miller|first=Alison|date=2018-05-08|title=Healing the Unimaginable|url=http://dx.doi.org/10.4324/9780429475467|doi=10.4324/9780429475467|isbn=9780429475467}}</ref><ref>Alayarian, A. (2018). Trauma, Torture and Dissociation: A Psychoanalytic View. (n.p.): Taylor & Francis.</ref><ref>Schwartz, H. L. (2013). The Alchemy of Wolves and Sheep: A Relational Approach to Internalized Perpetration in Complex Trauma Survivors. USA: Taylor & Francis.</ref> Earlier scientific debates in the 1980s and 1990s about torture-based ritual abuse in cults was known as "[[satanic ritual abuse]]" which was mainly viewed as a "[[moral panic]]."<ref>{{Cite journal|last1=Goode|first1=Erich|last2=Ben-Yehuda|first2=Nachman|date=1994|title=Moral Panics: Culture, Politics, and Social Construction|url=https://www.jstor.org/stable/2083363|journal=Annual Review of Sociology|volume=20|pages=149\u2013171|doi=10.1146/annurev.so.20.080194.001053|jstor=2083363|issn=0360-0572}}</ref>\n\n[[Kathleen Barry]], co-founder of  the [[United Nations]] NGO, the [[Coalition Against Trafficking in Women]] (CATW),<ref name="A Distinctive Style Article">{{cite web |url=http://www.adistinctivestyle.com/i/73080/96 |title=A Distinctive Style Article |access-date=21 January 2018 |archive-url=https://web.archive.org/web/20131021043933/http://www.adistinctivestyle.com/i/73080/96 |archive-date=21 October 2013 |url-status=dead }}</ref><ref name="On the Issues Article">{{cite web|url=http://www.ontheissuesmagazine.com/1995summer/pimping.php |title=On the Issues Article |publisher=Ontheissuesmagazine.com |access-date=2019-08-05}}</ref> prompted international awareness of human sex trafficking in her 1979 book ''Female Sexual Slavery''.<ref name="Biography at The People Speak Radio">[http://www.thepeoplespeakradio.net/2011/kathleen-barry/ Biography at The People Speak Radio] {{webarchive|url=https://web.archive.org/web/20120615092814/http://www.thepeoplespeakradio.net/2011/kathleen-barry/ |date=15 June 2012 }}</ref>  In his 1986 book ''Woman Abuse: Facts Replacing Myths,'' Lewis Okun reported that: "Kathleen Barry shows in ''Female Sexual Slavery'' that forced female prostitution involves coercive control practices very similar to thought reform."<ref>\nWoman Abuse: Facts Replacing Myths, Lewis Okun, SUNY Press, 1986, page 133</ref> In their 1996 book, ''Casting Stones: Prostitution and Liberation in Asia and the United States'', Rita Nakashima Brock and [[Susan Brooks Thistlethwaite]] report that the methods commonly used by [[pimps]] to control their victims "closely resemble the brainwashing techniques of terrorists and paranoid cults."<ref>Casting Stones: Prostitution and Liberation in Asia and the United States, Rita Nakashima Brock, Susan Brooks Thistlethwaite, Fortress Press, 1996, page 166</ref>\n\nIn his 2000 book, ''Destroying the World to Save It: Aum Shinrikyo, Apocalyptic Violence, and the New Global Terrorism'', Robert Lifton applied his original ideas about thought reform to [[Aum Shinrikyo]] and the [[War on Terrorism]], concluding that in this context thought reform was possible without violence or physical coercion. He also pointed out that in their efforts against terrorism Western governments were also using some alleged mind control techniques.<ref>Destroying the ''World to Save It: Aum Shinrikyo, Apocalyptic Violence, and the New Global Terrorism'', Owl Books, 2000.</ref>\n\nIn her 2004 [[popular science]] book, ''[[Brainwashing: The Science of Thought Control]]'', [[neuroscientist]] and [[physiologist]] [[Kathleen Taylor (biologist)|Kathleen Taylor]] reviewed the history of mind control theories, as well as notable incidents. In it she wrote that persons under the influence of brainwashing may have more rigid [[neurological]] pathways, and that can make it more difficult to rethink situations or to be able to later reorganize these pathways.<ref name="szimhart">{{cite journal | last =Szimhart | first =Joseph | title =Thoughts on thought control | journal =[[Skeptical Inquirer]] | volume =29 | issue =4 | pages =56\u201357 | date =July\u2013August 2005 }}</ref> Some reviewers praised the book for its clear presentation, while others criticized it for oversimplification.<ref name="lefanu">{{cite news | last =Le Fanu | first =James | title =Make up your mind | work =[[The Daily Telegraph]] | date =20 December 2004 | url =https://www.telegraph.co.uk/arts/main.jhtml?xml=/arts/2004/12/19/botay19.xml&sSheet=/arts/2004/12/19/bomain.html | access-date = 2008-11-02 }}{{dead link|date=July 2021|bot=medic}}{{cbignore|bot=medic}}</ref><ref name="hawkes">{{cite news | last =Hawkes | first =Nigel | title =Brainwashing by Kathleen Taylor | work =[[The Times]] | publisher =Times Newspapers Ltd | date =27 November 2004 | url =http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/books/article395436.ece | access-date = 2008-11-02 | location=London}}</ref><ref>{{cite news | last =Caterson | first =Simon | title =Hell to pay when man bites God | work =[[The Australian]] | page =4 | date =2 May 2007 }}</ref><ref>{{cite book |last=Taylor |first=Kathleen Eleanor |author-link=Kathleen Taylor (biologist) |title=Brainwashing: The Science of Thought Control |url=https://books.google.com/books?id=BIuju20yhDkC |access-date=2009-07-30 |date=December 2004 |publisher=Oxford University Press |isbn=978-0-19-280496-9 |page=215}}</ref>\n\nSome scholars have said that modern [[business corporation]]s practice mind control to create a work force that shares common values and culture.<ref>''Exploring Leadership: Individual, Organizational, and Societal Perspectives'', Richard Bolden, Beverley Hawkins, Jonathan Gosling, Scott Taylor, Oxford University Press, 30 June 2011, page 95.</ref> They have linked "corporate brainwashing" with [[globalization]], saying that corporations are attempting to create a worldwide [[Cultural homogenization|monocultural]] network of producers, consumers, and managers.<ref>''The Rise of the Anti-corporate Movement: Corporations and the People who Hate Them'', Evan Osborne, Greenwood Publishing Group, 2007, page 14</ref> Modern educational systems have also been criticized, by both the left and the right, for contributing to corporate brainwashing.<ref>''More Money Than Brains: Why School Sucks, College is Crap, & Idiots Think They're Right'', [[Laura Penny]], McClelland & Stewart, 20 April 2010, page 63.</ref> In his 1992 book, ''Democracy in an Age of Corporate Colonization'', [[Stanley A. Deetz]] says that modern "[[self awareness]]" and "[[self improvement]]" programs provide corporations with even more effective tools to control the minds of employees than traditional brainwashing was said to have been.<ref>''Democracy in an Age of Corporate Colonization: Developments in Communication and the Politics of Everyday Life'', Stanley Deetz, SUNY Press, 1 January 1992, page 257.</ref>\n\n {{Columns-list|colwidth=24em|\n* [[Abusive power and control]] \n* [[Behavior modification]]\n* [[Diminished responsibility]]\n* [[German-occupied Europe]]\n* [[Homo Sovieticus]]\n* [[Hypnosis]]\n* [[Indoctrination]] \n* [[Pedagogy]]\n* [[Political abuse of psychiatry]]\n* [[Manipulation (psychology)]]\n* [[Psychological warfare]]\n* [[Reality distortion field]]\n* [[Stockholm syndrome]]\n* ''[[Thought Reform and the Psychology of Totalism]]''\n* [[Unethical human experimentation in the United States]]\n}}\n{{clear}}\n\n * {{Cite book |author=Lifton, Robert J. |author-link=Robert Jay Lifton |title=Thought Reform and the Psychology of Totalism: A Study of "Brainwashing" in China |publisher=Norton |location=New York |year=1961 |isbn=978-0-8078-4253-9| ref = none}}; Reprinted, with a new preface: University of North Carolina Press, 1989 ([https://archive.org/details/ThoughtReformAndThePsychologyOfTotalism Online] at [[Internet Archive]]).\n* {{Cite book |author=Lifton, Robert J. |author-link=Robert Jay Lifton |title=Destroying the World to Save It: Aum Shinrikyo, Apocalyptic Violence, and the New Global Terrorism |year=2000 |publisher=Owl Books}}\n*{{cite web |author= Meerloo, Joost |url=http://www.lermanet.com/scientology/mc-ch1.html |title=The Rape of the Mind: The Psychology of Thought Control, Menticide, and Brainwashing |year=1956 |publisher=World Publishing Company|author-link=Joost Meerloo }}\n* {{cite web |author=Singer M |url=http://www.culteducation.com/reference/apologist/apologist23.html |title=Report of the APA Task Force on Deceptive and Indirect Techniques of Persuasion and Control (DIMPAC report) |publisher=[[American Psychological Association]] |date=1986-11-01 |access-date=2008-10-10|display-authors=etal|author-link=Margaret Singer }}\n* {{Cite book |author=Taylor, Kathleen |author-link=Kathleen Taylor (biologist) |title=Brainwashing: The Science of Thought Control |year=2004 |publisher=Oxford University Press}}\n* {{Cite journal |last=Zablocki |first=B. |title=The Blacklisting of a Concept. The Strange History of the Brainwashing Conjecture in the Sociology of Religion |journal=Nova Religio |volume=1 |issue=1 |pages=96\u2013121 |year=1997 |doi=10.1525/nr.1997.1.1.96 |author-link=Benjamin Zablocki}}\n* {{Cite journal |title=Exit Cost Analysis: A New Approach to the Scientific Study of Brainwashing |doi= 10.1525/nr.1998.1.2.216 |volume=2 |issue=1 |pages=216\u2013249 |last=Zablocki |first=B |author-link=Benjamin Zablocki |journal=Nova Religio |year=1998}}\n* {{Cite journal |author-link=Philip Zimbardo |last=Zimbardo |first=P. |title=Mind Control: Psychological Reality or Mindless Rhetoric? |journal=Monitor on Psychology |date=2002-11-01 |url=http://www.icsahome.com/articles/mind-control-zimbardo |access-date=2 June 2016 |archive-date=4 July 2016 |archive-url=https://web.archive.org/web/20160704120313/http://www.icsahome.com/articles/mind-control-zimbardo |url-status=dead }}\n\n {{Notelist}}\n\n {{Wikiquote}}\n{{Wiktionary|mind control}}\n{{Commons category-inline}}\n\n {{Commons|File:JOHN_L._McCLELLAN,.pdf|Communist Interrogation, Indoctrination, and Exploitation of Prisoners of War}}\n{{Reflist}}\n\n{{Manipulation (psychology)}}\n{{Opposition to NRMs}}\n{{Authority control}}\n\n\n[[es:Control mental]]\n[[it:Controllo mentale]]\n[[pt:Controle mental]]", "Brainwashing --- Introduction ---|China and the Korean War": "{{See also|Thought reform in China}}\nThe Chinese term ''x\u01d0n\u0103o'' (\u6d17\u8166\uff0c"wash brain")<ref>{{cite web |url=http://www.mdbg.net/chindict/chindict.php?page=worddict&wdrst=0&wdqb=%E6%B4%97%E8%85%A6 |title=Word dictionary - \u6d17\u8166 - MDBG English to Chinese dictionary |website=mdbg.net}}</ref> was originally used to describe the coercive [[persuasion]] used under the [[Maoist]] government in China, which aimed to transform "reactionary" people into "right-thinking" members of the new Chinese social system.<ref>{{cite book |last=Taylor |first= Kathleen |author-link= Kathleen Taylor (biologist) |title=Brainwashing: The Science of Thought Control |url= https://books.google.com/books?id=D3tYeMLc4hQC |access-date=2010-07-02 |year=2006 |publisher=Oxford University Press |location=Oxford, UK |isbn=978-0-19-920478-6 |page=5}}</ref> The term [[pun]]ned on the [[Taoist]] custom of "cleansing / washing the heart / mind" (''x\u01d0x\u012bn''\uff0c\u6d17\u5fc3) before conducting ceremonies or entering holy places.<ref group=lower-alpha>'''Note:''' ''x\u012bn'' can mean "heart", "mind" or "centre" depending on context. For example, {{lang|zh-Latn|[[:zh:\u5fc3\u810f\u75c5|x\u012bn z\u00e0ng b\u00ecng]]}} means [[Cardiovascular disease]], but {{lang|zh-Latn|[[:zh:\u5fc3\u7406\u533b\u751f|x\u012bn l\u01d0 y\u012b sh\u0113ng]]}} means [[psychologist]], and {{lang|zh-Latn|[[:zh:\u5e02\u4e2d\u5fc3|sh\u00ec zh\u014dng x\u012bn]]}} means [[Central business district]].</ref>\n\nThe ''[[Oxford English Dictionary]]'' records the earliest known English-language usage of the word "brainwashing" in an article by a journalist [[Edward Hunter (U.S. journalist)|Edward Hunter]], in ''Miami News'', published on 24 September 1950. Hunter was an outspoken [[Anti-communism|anticommunist]] and was alleged to be a [[CIA]] agent working undercover as a journalist.<ref>{{cite book |last=Marks |first=John |author-link=John D. Marks |title=The Search for the Manchurian Candidate: The CIA and mind control |url=https://archive.org/details/searchformanchur00john |access-date=2008-12-30 |year=1979 |publisher=Times Books |location=New York |isbn=978-0-8129-0773-5 |chapter=Chapter 8. Brainwashing |chapter-url=http://www.druglibrary.org/schaffer/lsd/marks8.htm |quote=In September 1950, the ''[[The Miami News|Miami News]]'' published an article by Edward Hunter titled \u2018"Brain-Washing" Tactics Force Chinese into Ranks of Communist Party\u2019. It was the first printed use in any language of the term "brainwashing", Hunter, a CIA propaganda operator who worked undercover as a journalist, turned out a steady stream of books and articles on the subject. }}</ref> Hunter and others used the Chinese term to explain why, during the [[Korean War]] (1950-1953), some American [[prisoners of war]] (POWs) cooperated with their Chinese captors, and even in a few cases [[List of American and British defectors in the Korean War|defected to their side]].<ref>{{cite news |first=Michael |last=Browning |title=Was kidnapped Utah teen brainwashed? |work=[[Palm Beach Post]] |location=Palm Beach |issn=1528-5758 |date=2003-03-14 |quote=During the Korean War, captured American soldiers were subjected to prolonged interrogations and harangues by their captors, who often worked in relays and used the "good-cop, bad-cop" approach \u2013 alternating a brutal interrogator with a gentle one. It was all part of "Xi Nao" (''washing the brain''). The Chinese and Koreans were making valiant attempts to convert the captives to the communist way of thought.}}</ref> British radio operator [[Robert W. Ford]]<ref>{{cite book |author=Ford, R.C. |author-link=Robert W. Ford |title=Captured in Tibet |publisher=[[Oxford University Press]] |location=Oxford [Oxfordshire] |year=1990 |isbn=978-0-19-581570-2}}</ref><ref>{{cite book |author-link=Robert W. Ford |author=Ford, R.C. |title=Wind between the Worlds: Captured in Tibet |publisher=SLG Books |year=1997 |isbn=978-0-9617066-9-2 |url-access=registration |url=https://archive.org/details/windbetweenworld00ford }}</ref> and British army Colonel [[James Carne]] also claimed that the Chinese subjected them to brainwashing techniques during their imprisonment.<ref>{{cite news |newspaper=[[The New York Times]] |url=https://timesmachine.nytimes.com/timesmachine/1953/02/23/83712037.pdf |title=Red germ charges cite 2 U.S. Marines |date=23 February 1954 |access-date=16 February 2012}}</ref>\n\nThe U.S. military and government laid charges of brainwashing in an effort to undermine  confessions made by POWs to war crimes, including [[Allegations of biological warfare in the Korean War|biological warfare]].<ref>{{cite book |first1=Stephen|last1=Endicott|first2=Edward|last2=Hagerman|title=The United States and Biological Warfare: Secrets from the early Cold War |url=https://archive.org/details/unitedstatesbiol00endi  |url-access=registration  |publisher=Indiana University Press |year=1998|isbn=9780253334725}}</ref> After Chinese radio broadcasts claimed to quote [[Frank Schwable]], Chief of Staff of the [[1st Marine Aircraft Wing|First Marine Air Wing]] admitting to participating in germ warfare, United Nations commander Gen. [[Mark W. Clark]] asserted:<ref>{{cite news |newspaper=The New York Times |url=https://timesmachine.nytimes.com/timesmachine/1953/02/24/93602632.pdf |title=Clark denounces germ war charges |date=24 February 1953 |access-date=16 February 2012}}</ref>\n:'' Whether these statements ever passed the lips of these unfortunate men is doubtful. If they did, however, too familiar are the mind-annihilating methods of these Communists in extorting whatever words they want... The men themselves are not to blame, and they have my deepest sympathy for having been used in this abominable way.''\n\nBeginning in 1953, [[Robert Jay Lifton]] interviewed American servicemen who had been POWs during the [[Korean War]] as well as priests, students, and teachers who had been held in prison in China after 1951. In addition to interviews with 25 Americans and Europeans, Lifton interviewed 15 Chinese citizens who had fled after having been subjected to indoctrination in Chinese universities. (Lifton's 1961 book ''[[Thought Reform and the Psychology of Totalism: A Study of "Brainwashing" in China]]'', was based on this research.)<ref>{{cite book |author=Wilkes, A.L. |title=Knowledge in Minds |page=323 |publisher=Psychology Press |year=1998 |isbn=978-0-86377-439-3}}</ref> Lifton found that when the POWs returned to the United States their thinking soon returned to normal, contrary to the popular image of "brainwashing."<ref name="Home_by_Ship">{{cite journal |title=Home by Ship: Reaction patterns of American prisoners of war repatriated from North Korea |journal=American Journal of Psychiatry |date=April 1954 |first=Robert J. |last=Lifton |volume=110 |issue=10 |pages=732\u2013739 |pmid=13138750 |doi=10.1176/ajp.110.10.732}}</ref>\n\nIn 1956, after reexamining the concept of brainwashing following the Korean War, the U.S. Army published a report entitled ''Communist Interrogation, Indoctrination, and Exploitation of Prisoners of War'', which called brainwashing a "popular misconception". The report concludes that  "exhaustive research of several government agencies failed to reveal even one conclusively documented case of 'brainwashing' of an American prisoner of war in Korea."<ref>{{cite book |author=U.S Department of the Army |title=Communist Interrogation, Indoctrination, and Exploitation of Prisoners of War. |publisher=U.S. Government Printing Office |id=Pamphlet number 30-101 |date=15 May 1956 |location=Washington, DC |url = http://palmm.digital.flvc.org/islandora/object/fau%3A32574/datastream/OBJ/view/Communist_interrogation_indoctrination__and_exploitation_of_prisoners_of_war.pdf| pages=17, 51}}</ref>", "Brainwashing --- Introduction ---|In popular culture": "{{Main|Mind control in popular culture}}\n[[File:Sinatra and Harvey in Manchurian Candidate NYWTS.jpg|thumb|left|150px|[[Laurence Harvey]] and [[Frank Sinatra]] in ''[[The Manchurian Candidate (1962 film)|The Manchurian Candidate]]'']]\nIn [[George Orwell]]'s 1949 [[dystopian]] novel ''[[Nineteen Eighty-Four]]'', the main character is subjected to imprisonment, [[isolation to facilitate abuse|isolation]], and torture in order to conform his thoughts and emotions to the wishes of the rulers of Orwell's fictional future [[totalitarian]] society. Orwell's vision influenced [[Edward Hunter (journalist)|Hunter]] and is still reflected in the popular understanding of the concept of brainwashing.<ref>{{cite book |title=Psychiatry and Public Affairs |author=Leo H. Bartemeier |publisher=Aldine Transaction |date=1 August 2011 |page=246}}</ref><ref>{{cite book |title=Encyclopedia of New Religious Movements |author=Clarke, Peter |publisher=Routledge |date=1 March 2004 |page=76}}</ref>\n\nIn the 1950s, some American films were made that featured brainwashing of POWs, including [[The Rack (1956 film)|''The Rack'']], ''[[The Bamboo Prison]]'', ''[[Toward the Unknown]]'', and ''[[The Fearmakers]]''. ''[[Forbidden Area]]'' told the story of Soviet secret agents who had been brainwashed through [[classical conditioning]] by their own government so they wouldn't reveal their identities. In 1962, [[The Manchurian Candidate (1962 film)|''The Manchurian Candidate'']] (based on the 1959 novel by [[Richard Condon]]) "put brainwashing front and center" by featuring a plot by the Soviet government to take over the United States by using a brainwashed [[sleeper agent]] for political assassination.<ref>{{cite book |title=Screen Enemies of the American Way: Political paranoia about Nazis, Communists, Saboteurs, Terrorists and Body Snatching Aliens in Film and Television |author=Sherman, Fraser A. |publisher=McFarland |date=13 December 2010}}</ref><ref>{{cite book |title=Brainwashing: A study in Cold War demonology |last=Seed |first=David |year=2004 |publisher=Kent State University Press |isbn=978-0-87338-813-9 |page=[https://archive.org/details/brainwashingfict0000seed/page/51 51] |url=https://archive.org/details/brainwashingfict0000seed/page/51 }}</ref><ref>{{cite web |url=http://www.listal.com/list/mind-control-movies-tv |title=Mind-control movies and TV |author=Steven a.k.a. Superant |website=listal.com |access-date=12 March 2016}}</ref>  The concept of brainwashing became popularly associated with the research of Russian psychologist [[Ivan Pavlov]], which mostly involved dogs as subjects.<ref>{{cite book |title=Judicial Policy Making and the Modern State: How the courts reformed America's prisons |author1=Feeley, Malcolm M. |author2=Rubin, Edward L. |publisher=Cambridge University Press |date=28 March 2000 |page=268}}</ref> In [[The Manchurian Candidate (1962 film)|''The Manchurian Candidate'']], the head brainwasher is "Dr. Yen Lo, of the Pavlov Institute."<ref>{{cite book |title=Asian Diaspora and East-West Modernity |author=Ma, Sheng-mei |publisher=Purdue University Press |year=2012 |page=129}}</ref>\n\nThe [[science fiction]] stories of [[Cordwainer Smith]] (pen name of Paul Myron Anthony Linebarger (1913-1966), a US Army officer who specialized in [[military intelligence]] and [[psychological warfare]] during the Second World War and the Korean War) depict brainwashing to remove memories of traumatic events as a normal and benign part of future medical practice.<ref>{{cite book |author1=Wolfe, Gary K. |author2=Williams, Carol T. |contribution=The Majesty of Kindness: The dialectic of Cordwainer Smith |title=Voices for the Future: Essays on major science fiction writers |volume=3 |editor=Clareson, Thomas D. |publisher=Popular Press |year=1983 |pages=53\u201372}}</ref>  In 1971, a film "A Clockwork Orange" positions institutional brainwashing as an option for violent convicts looking to shorten their sentences and in 1997's film "Conspiracy Theory," a mentally unstable, government-brainwashed assassin seeks to prove that some very powerful people have been tampering with his mind.<ref>{{Cite web|date=2006-05-10|title=How Brainwashing Works|url=https://science.howstuffworks.com/life/inside-the-mind/human-brain/brainwashing.htm|access-date=2021-09-13|website=HowStuffWorks|language=en}}</ref> \n\nA comedy movie to include brainwashing is the 1985 film [[Volunteers (1985 film)|Volunteers]] with [[Tom Hanks]] and [[John Candy]], where the latter's character is brainwashed by Communist guerillas while serving in the [[Peace Corps]].\n\nMind control remains an important theme in science fiction.  A subgenre is ''corporate mind control'', in which a future society is run by one or more business [[corporations]] that dominate society using [[advertising]] and [[mass media]] to control the population's thoughts and feelings.<ref>{{cite book |author=Schelde, Per |title=Androids, Humanoids, and other Science Fiction Monsters: Science and soul in science fiction films |url=https://archive.org/details/androidshumanoid00sche |url-access=limited |publisher=NYU Press |date=1 July 1994 |pages=[https://archive.org/details/androidshumanoid00sche/page/n180 169]\u2013175|isbn=9780585321172 }}</ref>  Terry O'Brien commented: "Mind control is such a powerful image that if [[hypnotism]] did not exist, then something similar would have to have been invented: The plot device is too useful for any writer to ignore. The fear of mind control is equally as powerful an image."<ref>{{cite book |author=O'Brien, Terry |title=The Greenwood Encyclopedia of Science Fiction and Fantasy: Themes, Works, and Wonders |volume=1 |editor=Westfahl, Gary |publisher=Greenwood Publishing Group |year=2005}}</ref>", "Brainwashing --- Introduction ---|Legal cases and the \"brainwashing defense\"": "[[File:Hearst-hibernia-yell.jpg|200 px|alt=|thumb|Bank robbery by [[Patty Hearst]] and [[Symbionese Liberation Army]] members<ref name="Famous Pictures Magazine">{{cite web |date= May 14, 2013 |url= http://www.famouspictures.org/patty-hearst/ |title= Patty Hearst |publisher= Famous Pictures Magazine |access-date= January 21, 2016 |last= Lucas |first=Dean}}</ref>]]\nThe concept of brainwashing has been raised in the defense of criminal charges.  It has also been raised in child custody cases.<ref>[[Richard Warshak|Warshak, R. A.]] (2010). ''Divorce Poison: How to Protect Your Family from Bad-mouthing and Brainwashing''. New York: Harper Collins.</ref><ref>Richardson, James T. ''Regulating Religion: Case Studies from Around the Globe'', Kluwer Academic/Plenum Publishers 2004, p. 16, {{ISBN|978-0-306-47887-1}}.</ref>  The 1969 to 1971 case of [[Charles Manson]], who was said to have brainwashed his followers to commit murder and other crimes, brought the issue to renewed public attention.<ref>''Minds on Trial: Great Cases in Law and Psychology'', by Charles Patrick Ewing, Joseph T. McCann pp. 34\u201336</ref><ref>Shifting the Blame: How Victimization Became a Criminal Defense, Saundra Davis Westervelt, Rutgers University Press, 1998. page 158</ref>\n\nIn 1974, [[Patty Hearst]], a member of the wealthy [[William Randolph Hearst|Hearst family]], was [[Kidnapping|kidnapped]] by the [[Symbionese Liberation Army]], a left-wing militant organization. After several weeks of captivity she agreed to join the group and took part in their activities.  In 1975, she was arrested and charged with bank robbery and use of a gun in committing a felony.  Her attorney, [[F. Lee Bailey]], argued in her trial that she should not be held responsible for her actions since her treatment by her captors was the equivalent of the alleged brainwashing of Korean War POWs (see also [[Diminished responsibility]]).<ref name="Regreligion">Regulating Religion: Case Studies from Around the Globe, James T. Richardson, Springer Science & Business Media, 6 December 2012, page 518</ref>  Bailey developed his case in conjunction with psychiatrist [[Louis Jolyon West]] and psychologist [[Margaret Singer]].  They had both studied the experiences of Korean War POWs. (In 1996 Singer published her theories in her best-selling book ''[[Cults in Our Midst]]''.<ref name="refocus.org">[http://www.refocus.org/singerne.html ''Cults in Our Midst: The Continuing Fight Against Their Hidden Menace''] {{webarchive|url=https://web.archive.org/web/20150202034934/http://www.refocus.org/singerne.html|date=2 February 2015}}, Margaret Thaler Singer, Jossey-Bass, publisher, April 2003, {{ISBN|0-7879-6741-6}}</ref><ref name="clarke">{{Cite book|last1=Clarke|first1=Peter|url=https://books.google.com/books?id=DouBAgAAQBAJ|title=Encyclopedia of New Religious Movements|last2=Clarke|first2=Reader in Modern History Fellow Peter|date=March 2004|isbn=9781134499700}}</ref><ref>{{Cite news|last=Hilts|first=Philip J.|date=9 January 1999|title=Louis J. West, 74, Psychiatrist Who Studied Extremes, Dies|newspaper=The New York Times|url=https://www.nytimes.com/1999/01/09/us/louis-j-west-74-psychiatrist-who-studied-extremes-dies.html|access-date=31 December 2016}}</ref>)   Despite this defense Hearst was found guilty.<ref name="Regreligion"/>\n\nIn 1990 [[Steven Fishman]], who was a member of the [[Church of Scientology]], was charged with [[mail fraud]] for conducting a scheme to sue large corporations via conspiring with minority stockholders in shareholder class action lawsuits. Afterwards, he would sign settlements that left those stockholders empty-handed. Fishman's attorneys notified the court that they intended to rely on an [[insanity defense]], using the theories of brainwashing and the expert witnesses of Singer and [[Richard Ofshe]] to claim that Scientology had practiced brainwashing on him which left him unsuitable to make independent decisions. The court ruled that the use of brainwashing theories is inadmissible in expert witnesses, citing the [[Frye standard]], which states that scientific theories utilized by expert witnesses must be generally accepted in their respective fields.<ref>{{cite news|title=United States v. Fishman (1990)|url=https://law.justia.com/cases/federal/district-courts/FSupp/743/713/2593631/|newspaper=Justia Law}}</ref>\n\nIn 2003, the brainwashing defense was used unsuccessfully in the defense of [[Lee Boyd Malvo]], who was charged with murder for his part in the [[D.C. sniper attacks]].<ref>Mental Condition Defences and the Criminal Justice System: Perspectives from Law and Medicine, Ben Livings, Alan Reed, Nicola Wake, Cambridge Scholars Publishing, 27 February 2015, Page 98</ref><ref name="Oldenburg">Oldenburg, Don (2003-11-21). [http://www.crimlaw.org/defbrief269.html "Stressed to Kill: The Defense of Brainwashing; Sniper Suspect's Claim Triggers More Debate"] {{webarchive|url=https://web.archive.org/web/20110501144721/http://www.crimlaw.org/defbrief269.html|date=1 May 2011}}, ''[[The Washington Post]]'', reproduced in ''Defence Brief'', issue 269, published by Steven Skurka & Associates</ref>\n\nSome legal scholars have argued that the brainwashing defense undermines the law's  fundamental premise of [[free will]].<ref>Freedom and Criminal Responsibility in American Legal Thought, Thomas Andrew Green, Cambridge University Press, 27 Oct 2014, page 391</ref><ref>LaFave's Criminal Law, 5th (Hornbook Series), Wayne LaFave, West Academic, 18 March 2010, pages 208-210</ref> In 2003, forensic psychologist [[Dick Anthony]] said that "no reasonable person would question that there are situations where people can be influenced against their best interests, but those arguments are evaluated on the basis of fact, not bogus expert testimony."<ref name="Oldenburg"/>", "Brainwashing --- Introduction ---|Anti-cult movement": "{{Main|Anti-cult movement}}\n\n[[File:Philip_Zimbardo_(cropped).jpg|thumb|left|150px|[[Phillip Zimbardo]]]]\nIn the 1970s and 1980s, the anti-cult movement applied the concept of brainwashing to explain seemingly sudden and dramatic [[religious conversion]]s to various [[new religious movement]]s (NRMs) and other groups that they considered [[cults]].<ref>{{cite web |first=J. Gordon |last=Melton |author-link=J. Gordon Melton |title=Brainwashing and the Cults: The Rise and Fall of a Theory |url=http://www.cesnur.org/testi/melton.htm |publisher=CESNUR: Center for Studies on New Religions |date=1999-12-10 |access-date=2009-06-15 |quote=In the United States at the end of the 1970s, brainwashing emerged as a popular theoretical construct around which to understand what appeared to be a sudden rise of new and unfamiliar religious movements during the previous decade, especially those associated with the hippie street-people phenomenon.}}</ref><ref name="BromleyEncy">{{cite book |chapter=Brainwashing |last=Bromley |first= David G. |year=1998 |pages=61\u201362 |title=Encyclopedia of Religion and Society |editor=William H. Swatos Jr. |publisher=AltaMira |location=Walnut Creek, CA |isbn=978-0-7619-8956-1}}</ref><ref>Barker, Eileen: ''New Religious Movements: A Practical Introduction''. London: Her Majesty's Stationery office, 1989.</ref>  News media reports tended to support the brainwashing view<ref name="Wright">{{cite journal |author=Wright, Stewart A. |year=1997 |title=Media Coverage of Unconventional Religion: Any 'Good News' for Minority Faiths? |journal=Review of Religious Research |volume=39 |issue=2 |pages=101\u2013115 |doi=10.2307/3512176 |jstor=3512176}}</ref> and [[social scientists]] sympathetic to the anti-cult movement, who were usually [[psychologists]], developed revised models of mind control.<ref name="BromleyEncy" /> While some psychologists were receptive to the concept, sociologists were for the most part skeptical of its ability to explain conversion to NRMs.<ref name="BarkerAReview">{{cite journal |author=Barker, Eileen |year=1986 |title=Religious Movements: Cult and Anti-Cult Since Jonestown |journal=Annual Review of Sociology |volume=12 |pages=329\u2013346 |doi=10.1146/annurev.so.12.080186.001553}}</ref>\n\n[[Philip Zimbardo]] defined mind control as "the process by which individual or collective freedom of choice and action is compromised by agents or agencies that modify or distort perception, motivation, affect, cognition or behavioral outcomes,"<ref name="Zimbardo 2002">{{cite journal |last=Zimbardo |first=Philip G. |author-link=Philip Zimbardo |date=November 2002 |title=Mind Control: Psychological Reality or Mindless Rhetoric? |journal=Monitor on Psychology |url=http://www.icsahome.com/articles/mind-control-zimbardo |access-date=2016-06-02 |quote=Mind control is the process by which individual or collective freedom of choice and action is compromised by agents or agencies that modify or distort perception, motivation, affect, cognition or behavioral outcomes. It is neither magical nor mystical, but a process that involves a set of basic social psychological principles. Conformity, compliance, persuasion, dissonance, reactance, guilt and fear arousal, modeling and identification are some of the staple social influence ingredients well studied in psychological experiments and field studies. In some combinations, they create a powerful crucible of extreme mental and behavioral [[Psychological manipulation|manipulation]] when synthesized with several other real-world factors, such as charismatic, authoritarian leaders, dominant ideologies, social isolation, physical debilitation, induced phobias, and extreme threats or promised rewards that are typically deceptively orchestrated, over an extended time period in settings where they are applied intensively. A body of social science evidence shows that when systematically practiced by state-sanctioned police, military or destructive cults, mind control can induce false confessions, create converts who willingly torture or kill 'invented enemies,' and engage indoctrinated members to work tirelessly, give up their money\u2014and even their lives\u2014for 'the cause.' |archive-date=4 July 2016 |archive-url=https://web.archive.org/web/20160704120313/http://www.icsahome.com/articles/mind-control-zimbardo |url-status=dead }}</ref> and he suggested that any human being is susceptible to such manipulation.<ref name="Zimbardo 1997 14">{{cite journal |last=Zimbardo |first=P |author-link=Philip Zimbardo |url=http://www.csj.org/studyindex/studycult/study_zimbar.htm |page=14 |title=What messages are behind today's cults? |journal=Monitor on Psychology |year=1997 |access-date=1 October 2009 |archive-date=2 May 1998 |archive-url=https://web.archive.org/web/19980502070642/http://csj.org/studyindex/studycult/study_zimbar.htm |url-status=dead }}</ref>\n\n[[Benjamin Zablocki]] asserted that brainwashing is not "a process that is directly observable,"<ref name="linfran">{{cite web |last1=Allen |first1=Charlotte |title=Brainwashed! Scholars of Cults Accuse Each Other of Bad Faith |url=http://linguafranca.com/9812/allen.html |archive-url=https://web.archive.org/web/20001203192600/http://linguafranca.com/9812/allen.html |website=Lingua Franca |archive-date=2000-12-03 |date=December 1998 |publisher=linguafranca.com |access-date=2014-06-16}}</ref> and that the "real sociological issue" is whether "brainwashing occurs frequently enough to be considered an important social problem."<ref name="Zablocki1997" />  According to Zablocki other scholars commonly mistook brainwashing for both a recruiting and a retaining process, when it is merely the latter.<ref name="Zablocki2001">{{cite book |last=Zablocki|first=Benjamin |title=Misunderstanding Cults: Searching for Objectivity in a Controversial Field |year=2001 |publisher=U of Toronto Press |isbn=978-0-8020-8188-9 |page=176}}</ref> He also asserted that the number of people who attest to brainwashing in interviews (performed in accordance with guidelines of the [[National Institute of Mental Health]] and [[National Science Foundation]]) is too large to result from anything other than a genuine phenomenon.<ref name="zablocki-p194-201">{{cite book |last=Zablocki|first=Benjamin |title=Misunderstanding Cults: Searching for Objectivity in a Controversial Field |year=2001 |publisher=U of Toronto Press |isbn=978-0-8020-8188-9 |pages=194\u2013201}}</ref>  Zablocki also pointed out that in the two most prestigious journals dedicated to the [[sociology of religion]] there have been no articles "supporting the brainwashing perspective," while over one hundred such articles have been published in other journals "marginal to the field."<ref name="Zablocki1998">{{cite journal |title=TReply to Bromley |journal=Nova Religio |date=April 1998 |first=Benjamin. |last=Zablocki |volume=1 |issue=2 |pages=267\u2013271 |doi=10.1525/nr.1998.1.2.267}}</ref> He concluded that the concept of brainwashing had been unfairly [[blacklisted]].<ref name="Melton" /><ref name="Zablocki1997">{{cite journal |journal=Nova Religio |date=October 1997 |first=Benjamin. |last=Zablocki |volume=1 |issue=1 |pages=96\u2013121 |doi=10.1525/nr.1997.1.1.96|title=The Blacklisting of a Concept: The Strange History of the Brainwashing Conjecture in the Sociology of Religion }}</ref><ref name="Zablocki1998" /><ref>Phil Zuckerman. Invitation to the Sociology of Religion. Psychology Press, 24 July 2003 p. 28</ref>\n\n[[Eileen Barker]] criticized the concept of mind control because it functioned to justify costly interventions such as [[deprogramming]] or exit counseling.<ref name="Rusher">[https://web.archive.org/web/20050415093632/http://www.findarticles.com/p/articles/mi_m1282/is_v38/ai_4580948 Review], [[William Rusher]], ''[[National Review]]'', 19 December 1986.</ref> She has also criticized some mental health professionals, including Singer, for accepting expert witness jobs in court cases involving NRMs.<ref name="BarkerJoke">{{cite journal |author=Barker, Eileen |year=1995 |title=The Scientific Study of Religion? You Must Be Joking! |journal=Journal for the Scientific Study of Religion |volume=34 |issue=3 |pages=287\u2013310 |doi=10.2307/1386880 |jstor=1386880}}</ref> Her 1984 book, ''[[The Making of a Moonie: Choice or Brainwashing?]]''<ref>[[Eileen Barker]], ''The Making of a Moonie: Choice or Brainwashing?'', [[Blackwell's|Blackwell Publishers]], Oxford, United Kingdom, {{ISBN|0-631-13246-5}}.</ref> describes the religious conversion process to the [[Unification Church]] (whose members are sometimes informally referred to as ''[[Moonie (nickname)|Moonies]]''), which had been one of the best known groups said to practice brainwashing.<ref name="Barker2012">[http://religion.blogs.cnn.com/2012/09/03/my-take-moons-death-marks-end-of-an-era/ Moon\u2019s death marks end of an era], [[Eileen Barker]], [[CNN]], 3 September 2012, Although Moon is likely to be remembered for all these things \u2013 mass weddings, accusations of brainwashing, political intrigue and enormous wealth \u2013 he should also be remembered as creating what was arguably one of the most comprehensive and innovative theologies embraced by a new religion of the period.</ref><ref name="usatoday2012-09-02a">{{cite news|url=http://usatoday30.usatoday.com/news/world/story/2012-09-02/unification-church-rev-moon-dies/57537454/1|title=Unification Church founder Rev. Sun Myung Moon dies at 92|author=Hyung-Jin Kim|work=USA Today|issn=0734-7456|date=2 September 2012|access-date=2 September 2012|quote=The Rev. Sun Myung Moon was a self-proclaimed messiah who built a global business empire. He called both North Korean leaders and American presidents his friends, but spent time in prisons in both countries. His followers around the world cherished him, while his detractors accused him of brainwashing recruits and extracting money from worshippers.|archive-date=29 September 2012|archive-url=https://web.archive.org/web/20120929230011/http://usatoday30.usatoday.com/news/world/story/2012-09-02/unification-church-rev-moon-dies/57537454/1|url-status=dead}}</ref> Barker spent close to seven years studying Unification Church members and wrote that she rejects the "brainwashing" theory, because it explains neither the many people who attended a recruitment meeting and did not become members, nor the voluntary disaffiliation of members.<ref name="Rusher" /><ref>[https://web.archive.org/web/20060618211708/http://web.uni-marburg.de/religionswissenschaft/journal/diskus/chryssides.html New Religious Movements - Some Problems of Definition] [[George Chryssides]], ''Diskus'', 1997.</ref><ref>[http://faculty.arec.umd.edu/cmcausland/RALi/The%20Market%20for%20Martyrs.pdf The Market for Martyrs] {{webarchive|url=https://web.archive.org/web/20120111212356/http://faculty.arec.umd.edu/cmcausland/RALi/The%20Market%20for%20Martyrs.pdf |date=11 January 2012 }}, [[Laurence Iannaccone]], [[George Mason University]], 2006, "One of the most comprehensive and influential studies was The Making of a Moonie: Choice or Brainwashing? by Eileen Barker (1984). Barker could find no evidence that Moonie recruits were ever kidnapped, confined, or coerced. Participants at Moonie retreats were not [[deprived of sleep]]; the lectures were not "trance-inducing" and there was not much chanting, no drugs or alcohol, and little that could be termed "frenzy" or "ecstatic" experience. People were free to leave, and leave they did. Barker\u2019s extensive enumerations showed that among the recruits who went so far as to attend two-day retreats (claimed to beMoonie\u2019s most effective means of "brainwashing"), fewer than 25% joined the group for more than a week and only 5% remained full-time members one year later. And, of course, most contacts dropped out before attending a retreat. Of all those who visited a Moonie centre at least once, not one in two-hundred remained in the movement two years later. With failure rates exceeding 99.5%, it comes as no surprise that full-time Moonie membership in the U.S. never exceeded a few thousand. And this was one of the most New Religious Movements of the era!"</ref><ref>Oakes, Len "By far the best study of the conversion process is Eileen Barker\u2019s The Making of a Moonie [...]" from ''Prophetic Charisma: The Psychology of Revolutionary Religious Personalities'', 1997, {{ISBN|0-8156-0398-3}}</ref><ref>Storr, Anthony ''Feet of clay: a study of gurus'' 1996 {{ISBN|0-684-83495-2}}</ref>\n\n[[James Richardson (sociologist)|James Richardson]] observed that if the new religious movements had access to powerful brainwashing techniques, one would expect that they would have high growth rates, yet in fact most have not had notable success in recruiting or retaining members<ref name="Richardson1985">{{cite journal |title=The active vs. passive convert: paradigm conflict in conversion/recruitment research |journal=Journal for the Scientific Study of Religion |date=June 1985 |first=James T. |last=Richardson |volume=24 |issue=2 |pages=163\u2013179 |doi=10.2307/1386340 |jstor=1386340}}</ref> For this and other reasons, sociologists of religion including [[David G. Bromley|David Bromley]] and [[Anson Shupe]] consider the idea that "cults" are brainwashing American youth to be "implausible."<ref name="brain_wash">{{cite web|url=http://www.religioustolerance.org/brain_wa.htm|title=Brainwashing by Religious Cults|work=religioustolerance.org}}</ref> [[Thomas Robbins (sociologist)|Thomas Robbins]], [[Massimo Introvigne]], [[Lorne Dawson]], [[Gordon Melton]], [[Marc Galanter (psychiatrist)|Marc Galanter]], and [[Saul Levine]], amongst other scholars researching NRMs, have argued and established to the satisfaction of courts, relevant professional associations and scientific communities that there exists no generally accepted scientific theory, based upon methodologically sound research, that supports the concept of brainwashing.<ref>Richardson, James T. 2009. "Religion and The Law" in The Oxford Handbook of the Sociology of Religion. Peter Clarke. (ed) Oxford Handbooks Online. p. 426</ref>\n\nIn 1999 [[forensic psychologist]] [[Dick Anthony]] criticized another adherent to this view, [[Jean-Marie Abgrall]], for allegedly employing a [[pseudo-scientific]] approach and lacking any evidence that anyone's [[worldview]] was substantially changed by these coercive methods. He claimed that the concept and the fear surrounding it was used as a tool for the anti-cult movement to rationalize the persecution of minority religious groups.<ref>{{cite journal | doi=10.1023/A:1022081411463 | volume=12 | issue=4 | title=Pseudoscience and Minority Religions: An Evaluation of the Brainwashing Theories of Jean-Marie Abgrall | journal=Social Justice Research | pages=421\u2013456|year = 1999|last1 = Anthony|first1 = Dick| s2cid=140454555 }}</ref>\n\nIn 2016, Israeli anthropologist of religion and fellow at the [[Van Leer Jerusalem Institute]] Adam Klin-Oron said about then-proposed "anti-cult" legislation: \n{{Quote|In the 1980s there was a wave of \u2018brainwashing\u2019 claims, and then parliaments around the world examined the issue, courts around the world examined the issue, and reached a clear ruling: That there is no such thing as cults\u2026that the people making these claims are often not experts on the issue. And in the end courts, including in Israel, rejected expert witnesses who claimed there is "brainwashing."<ref>[http://www.timesofisrael.com/will-israels-first-anti-cult-legislation-harm-religious-freedom], ''[[Times of Israel]]<nowiki>''</nowiki>''</ref>''}}", "Brainwashing --- Introduction ---|Scientific research": "[[File:ProjectMKULTRA Senate Report.pdf|thumb|1977 United States Senate report on [[Project MKUltra]], the [[Central Intelligence Agency]]'s program of research into brainwashing]]\n\n {{Main|APA Task Force on Deceptive and Indirect Methods of Persuasion and Control}}\n\nIn 1983, the [[American Psychological Association]] (APA) asked Singer to chair a [[taskforce]] called the APA Task Force on Deceptive and Indirect Techniques of Persuasion and Control (DIMPAC) to investigate whether brainwashing or coercive persuasion did indeed play a role in recruitment by NRMs.\n<ref>\nAs archived at http://www.cesnur.org/testi/DIMPAC.htm, retrieved 2008-06-23\n</ref> It came to the following conclusion:<ref>\n{{cite web\n| url         = http://www.cesnur.org/testi/APA.htm\n| title       = Memorandum\n| access-date  = 2008-11-18\n| author      = American Psychological Association Board of Social and Ethical Responsibility for Psychology (BSERP)\n| date        = 1987-05-11\n| work        = CESNUR: APA Memo of 1987 with Enclosures\n| publisher   = CESNUR Center for Studies on New Religions\n| quote       = BSERP requests that Task Force members not distribute or publicize the report without indicating that the report was unacceptable to the Board.\n}}\n</ref>\n\n<blockquote>\n''Cults and [[large group awareness training]]s have generated considerable controversy because of their widespread use of deceptive and indirect techniques of persuasion and control. These techniques can compromise individual freedom, and their use has resulted in serious harm to thousands of individuals and families. This report reviews the literature on this subject, proposes a new way of conceptualizing influence techniques, explores the ethical ramifications of deceptive and indirect techniques of persuasion and control, and makes recommendations addressing the problems described in the report.''\n</blockquote>\n\nOn 11 May 1987, the APA's Board of Social and Ethical Responsibility for Psychology (BSERP) rejected the DIMPAC report because the report "lacks the scientific rigor and evenhanded critical approach necessary for APA imprimatur", and concluded that "after much consideration, BSERP does not believe that we have sufficient information available to guide us in taking a position on this issue."<ref>{{cite web |url=http://www.cesnur.org/testi/APA.htm |title=Memorandum |access-date=2008-11-18 |author=American Psychological Association Board of Social and Ethical Responsibility for Psychology (BSERP) |date=1987-05-11 |work=CESNUR: APA Memo of 1987 with Enclosures |publisher=CESNUR Center for Studies on New Religion |quote=BSERP thanks the Task Force on Deceptive and Indirect Methods of Persuasion and Control for its service but is unable to accept the report of the Task Force. In general, the report lacks the scientific rigor and evenhanded critical approach necessary for APA imprimatur.}}</ref>\n\n {{Main|Project MKUltra}}\nFor 20 years starting in the early 1950s, the [[United States Central Intelligence Agency]] (CIA) and the [[United States Department of Defense]] conducted secret research, including [[Project MKUltra]], in an attempt to develop practical brainwashing techniques; These experiments ranged "from [[electroshock]] to high doses of [[Lysergic acid diethylamide|LSD]]".<ref name=":0">{{Cite news|url=https://www.npr.org/2019/09/09/758989641/the-cias-secret-quest-for-mind-control-torture-lsd-and-a-poisoner-in-chief|title = The CIA's Secret Quest for Mind Control: Torture, LSD and A 'Poisoner in Chief'|newspaper = NPR.org}}</ref> The full extent of the results are unknown. The director [[Sidney Gottlieb]] and his team, however, were apparently able to "blast away the existing mind" of a human being by using torture techniques<ref name=":0" /> \u2013 reprogramming, however, in terms of finding "a way to insert a new mind into that resulting void"<ref name=":0" /> was not so successful at least at the time.<ref name="Anthony">{{cite journal |author=Anthony, Dick |year=1999 |title=Pseudoscience and Minority Religions: An evaluation of the brainwashing theories of Jean-Marie |journal=Social Justice Research |volume=12 |issue=4 |pages=421\u2013456 |doi=10.1023/A:1022081411463|s2cid=140454555 }}</ref><ref>{{cite web|url=http://www.eh.doe.gov/ohre/roadmap/achre/chap3_4.html |title=Chapter 3, part 4: Supreme Court Dissents Invoke the Nuremberg Code: CIA and DOD Human Subjects Research Scandals |work=Advisory Committee on Human Radiation Experiments Final Report |access-date=24 August 2005 |url-status=dead |archive-url=https://web.archive.org/web/20041109061412/http://www.eh.doe.gov/ohre/roadmap/achre/chap3_4.html |archive-date=9 November 2004 }} "MKUltra, began in 1950 and was motivated largely in response to alleged Soviet, Chinese, and North Korean uses of mind-control techniques on U.S. prisoners of war in Korea."</ref> Some scholars such as the controversial psychiatrist [[Colin A. Ross]] claim, however, that the CIA was successful in creating programmable so-called "''[[The Manchurian Candidate|Manchurian Candidates]]"'' even at the time.<ref>{{Cite journal|url=https://doi.org/10.1300/J229v02n03_08|doi = 10.1300/J229v02n03_08|title = Book Review|journal = Journal of Trauma & Dissociation|year = 2001|volume = 2|issue = 3|pages = 123\u2013128|s2cid = 220439052}}</ref> The CIA experiments using various psychedelic drugs such as LSD and [[Mescaline]] drew from previous [[Nazi human experimentation]].<ref>The Search for the Manchurian Candidate: The CIA and Mind Control: By John Marks.  P 93 (c)1979 by John Marks Published by Times Books {{ISBN|0-8129-0773-6}}</ref>\n\nA bipartisan Senate Armed Services Committee report, released in part in December 2008 and in full in April 2009, reported that US military trainers who came to [[Guant\u00e1namo Bay]] in December 2002 had based an interrogation class on a chart copied from a 1957 Air Force study of "Chinese Communist"  brainwashing techniques. The report showed how the Secretary of Defense's 2002 authorization of the aggressive techniques at Guant\u00e1namo led to their use in [[Afghanistan]] and in [[Iraq]], including at [[Abu Ghraib]].<ref>{{cite news |last=Chaddock |first=Gail Russell |url=https://www.csmonitor.com/USA/Politics/2009/0422/report-says-top-officials-set-tone-for-detainee-abuse |title=Report says top officials set tone for detainee abuse |work=[[The Christian Science Monitor]] |date=April 22, 2009 |access-date=2020-01-03 }}</ref>", "Brainwashing --- Introduction ---|Other areas and studies": "[[File:Joost-a-m-meerloo.jpg|thumb|right|150px|[[Joost Meerloo]]]]\n[[Joost Meerloo]], a Dutch psychiatrist, was an early proponent of the concept of brainwashing. ("Menticide" is a [[neologism]] coined by him meaning: "killing of the mind.") Meerloo's view was influenced by his experiences during the German occupation of his country and his work with the Dutch government and the American military in the [[interrogation]] of accused [[Nazi war criminals]]. He later emigrated to the United States and taught at [[Columbia University]].<ref>The Oxford Handbook of Propaganda Studies, Jonathan Auerbach, Russ Castronovo, Oxford University Press, 2014, page 114</ref> His best-selling 1956 book, ''The Rape of the Mind'', concludes by saying: \n:''The modern techniques of brainwashing and menticide\u2014those perversions of psychology\u2014can bring almost any man into submission and surrender. Many of the victims of thought control, brainwashing, and menticide that we have talked about were strong men whose minds and wills were broken and degraded. But although the totalitarians use their knowledge of the mind for vicious and unscrupulous purposes, our democratic society can and must use its knowledge to help man to grow, to guard his freedom, and to understand himself.'' <ref>*{{cite web |author= Meerloo, Joost |url=http://www.lermanet.com/scientology/mc-ch1.html |title=The Rape of the Mind: The Psychology of Thought Control, Menticide, and Brainwashing |year=1956 |publisher=World Publishing Company|author-link=Joost Meerloo }}</ref>\n\nRussian historian [[Daniel Romanovsky]], who interviewed survivors and eyewitnesses in the 1970s, reported on what he called "[[Nazi]] brainwashing" of the people of [[Belarus]] by the occupying Germans during the [[Second World War]], which took place through both mass [[propaganda]] and intense re-education, especially in schools. Romanovsky noted that very soon most people had adopted the Nazi view that the Jews were an inferior race and were closely tied to the [[Soviet]] government, views that had not been at all common before the German occupation.<ref>''Nazi Europe and the Final Solution'', David Bankier, Israel Gutman, Berghahn Books, 2009, page 282-285.</ref><ref>Gray Zones: Ambiguity and Compromise in the Holocaust and its Aftermath, Jonathan Petropoulos, John Roth, Berghahn Books, 15 July 2005, page 209</ref><ref>The Minsk Ghetto 1941-1943: Jewish Resistance and Soviet Internationalism, Barbara Epstein, University of California Press, 2008, page 295</ref><ref>Bringing the Dark Past to Light: The Reception of the Holocaust in Postcommunist Europe, John-Paul Himka, Joanna Beata Michlic, University of Nebraska Press, 1 July 2013, pages 74, 78</ref><ref>{{cite web|url=http://www.angelfire.com/sc3/soviet_jews_exodus/English/Interview_s/InterviewRomanovsky.shtml |title=Interview |publisher=Angelfire.com |access-date=2019-08-05}}</ref><ref>*{{citation|chapter-url=https://books.google.com/books?id=oU6WielZ_VoC&pg=PA276|chapter=The Soviet Person as a Bystander of the Holocaust: The case of eastern Belorussia|first=Daniel|last=Romanovsky|page=276|title=Nazi Europe and the Final Solution|editor-first=David|editor-last=Bankier|editor2-first=Israel|editor2-last=Gutman|year=2009|publisher=Berghahn Books|isbn=9781845454104}}\n*{{cite journal|title=The Holocaust in the Eyes of Homo Sovieticus: A Survey Based on Northeastern Belorussia and Northwestern Russia|journal=Holocaust and Genocide Studies|year=1999|volume=13|issue=3|pages=355\u2013382|doi=10.1093/hgs/13.3.355|last1=Romanovsky|first1=D.}}\n*{{citation|first=Daniel|last=Romanovsky|chapter=Soviet Jews Under Nazi Occupation in Northeastern Belarus and Western Russia|title=Bitter Legacy: Confronting the Holocaust in the USSR|editor-first=Zvi|editor-last=Gitelman|year=1997|publisher=Indiana University Press|page=241}}</ref>\n\n[[Italy]] has had controversy over the concept of ''[[plagio]]'', a crime consisting in an absolute psychological\u2014and eventually physical\u2014domination of a person. The effect is said to be the annihilation of the subject's [[freedom]] and [[self-determination]] and the consequent negation of his or her [[personality]]. The crime of plagio has rarely been prosecuted in Italy, and only one person was ever convicted. In 1981, an Italian court found that the concept is imprecise, lacks coherence and is liable to arbitrary application.<ref>Alessandro Usai "Profili penali dei condizionamenti mentali, Milano, 1996 {{ISBN|88-14-06071-1}}.</ref>\n\nRecent scientific book publications in the field of the [[mental disorder]] "[[dissociative identity disorder]]" (DID) mention [[torture]]-based brainwashing by criminal networks and malevolent actors as a deliberate means to create multiple "programmable" personalities in a person to exploit this individual for sexual and financial reasons.<ref>{{Citation|last=Schwartz|first=Rachel Wingfield|title="An evil cradling"? Cult practices and the manipulation of attachment needs in ritual abuse|date=2018-03-22|url=http://dx.doi.org/10.4324/9780429479700-2|work=Ritual Abuse and Mind Control|pages=39\u201355|publisher=Routledge|doi=10.4324/9780429479700-2|isbn=978-0-429-47970-0|access-date=2021-07-11}}</ref><ref>{{Citation|last=Miller|first=Alison|chapter=Becoming Yourself|date=2018-05-11|chapter-url=http://dx.doi.org/10.4324/9780429472251-21|pages=347\u2013370|publisher=Routledge|doi=10.4324/9780429472251-21|isbn=978-0-429-47225-1|access-date=2021-07-11}}</ref><ref>{{Cite book|last=Miller|first=Alison|date=2018-05-08|title=Healing the Unimaginable|url=http://dx.doi.org/10.4324/9780429475467|doi=10.4324/9780429475467|isbn=9780429475467}}</ref><ref>Alayarian, A. (2018). Trauma, Torture and Dissociation: A Psychoanalytic View. (n.p.): Taylor & Francis.</ref><ref>Schwartz, H. L. (2013). The Alchemy of Wolves and Sheep: A Relational Approach to Internalized Perpetration in Complex Trauma Survivors. USA: Taylor & Francis.</ref> Earlier scientific debates in the 1980s and 1990s about torture-based ritual abuse in cults was known as "[[satanic ritual abuse]]" which was mainly viewed as a "[[moral panic]]."<ref>{{Cite journal|last1=Goode|first1=Erich|last2=Ben-Yehuda|first2=Nachman|date=1994|title=Moral Panics: Culture, Politics, and Social Construction|url=https://www.jstor.org/stable/2083363|journal=Annual Review of Sociology|volume=20|pages=149\u2013171|doi=10.1146/annurev.so.20.080194.001053|jstor=2083363|issn=0360-0572}}</ref>\n\n[[Kathleen Barry]], co-founder of  the [[United Nations]] NGO, the [[Coalition Against Trafficking in Women]] (CATW),<ref name="A Distinctive Style Article">{{cite web |url=http://www.adistinctivestyle.com/i/73080/96 |title=A Distinctive Style Article |access-date=21 January 2018 |archive-url=https://web.archive.org/web/20131021043933/http://www.adistinctivestyle.com/i/73080/96 |archive-date=21 October 2013 |url-status=dead }}</ref><ref name="On the Issues Article">{{cite web|url=http://www.ontheissuesmagazine.com/1995summer/pimping.php |title=On the Issues Article |publisher=Ontheissuesmagazine.com |access-date=2019-08-05}}</ref> prompted international awareness of human sex trafficking in her 1979 book ''Female Sexual Slavery''.<ref name="Biography at The People Speak Radio">[http://www.thepeoplespeakradio.net/2011/kathleen-barry/ Biography at The People Speak Radio] {{webarchive|url=https://web.archive.org/web/20120615092814/http://www.thepeoplespeakradio.net/2011/kathleen-barry/ |date=15 June 2012 }}</ref>  In his 1986 book ''Woman Abuse: Facts Replacing Myths,'' Lewis Okun reported that: "Kathleen Barry shows in ''Female Sexual Slavery'' that forced female prostitution involves coercive control practices very similar to thought reform."<ref>\nWoman Abuse: Facts Replacing Myths, Lewis Okun, SUNY Press, 1986, page 133</ref> In their 1996 book, ''Casting Stones: Prostitution and Liberation in Asia and the United States'', Rita Nakashima Brock and [[Susan Brooks Thistlethwaite]] report that the methods commonly used by [[pimps]] to control their victims "closely resemble the brainwashing techniques of terrorists and paranoid cults."<ref>Casting Stones: Prostitution and Liberation in Asia and the United States, Rita Nakashima Brock, Susan Brooks Thistlethwaite, Fortress Press, 1996, page 166</ref>\n\nIn his 2000 book, ''Destroying the World to Save It: Aum Shinrikyo, Apocalyptic Violence, and the New Global Terrorism'', Robert Lifton applied his original ideas about thought reform to [[Aum Shinrikyo]] and the [[War on Terrorism]], concluding that in this context thought reform was possible without violence or physical coercion. He also pointed out that in their efforts against terrorism Western governments were also using some alleged mind control techniques.<ref>Destroying the ''World to Save It: Aum Shinrikyo, Apocalyptic Violence, and the New Global Terrorism'', Owl Books, 2000.</ref>\n\nIn her 2004 [[popular science]] book, ''[[Brainwashing: The Science of Thought Control]]'', [[neuroscientist]] and [[physiologist]] [[Kathleen Taylor (biologist)|Kathleen Taylor]] reviewed the history of mind control theories, as well as notable incidents. In it she wrote that persons under the influence of brainwashing may have more rigid [[neurological]] pathways, and that can make it more difficult to rethink situations or to be able to later reorganize these pathways.<ref name="szimhart">{{cite journal | last =Szimhart | first =Joseph | title =Thoughts on thought control | journal =[[Skeptical Inquirer]] | volume =29 | issue =4 | pages =56\u201357 | date =July\u2013August 2005 }}</ref> Some reviewers praised the book for its clear presentation, while others criticized it for oversimplification.<ref name="lefanu">{{cite news | last =Le Fanu | first =James | title =Make up your mind | work =[[The Daily Telegraph]] | date =20 December 2004 | url =https://www.telegraph.co.uk/arts/main.jhtml?xml=/arts/2004/12/19/botay19.xml&sSheet=/arts/2004/12/19/bomain.html | access-date = 2008-11-02 }}{{dead link|date=July 2021|bot=medic}}{{cbignore|bot=medic}}</ref><ref name="hawkes">{{cite news | last =Hawkes | first =Nigel | title =Brainwashing by Kathleen Taylor | work =[[The Times]] | publisher =Times Newspapers Ltd | date =27 November 2004 | url =http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/books/article395436.ece | access-date = 2008-11-02 | location=London}}</ref><ref>{{cite news | last =Caterson | first =Simon | title =Hell to pay when man bites God | work =[[The Australian]] | page =4 | date =2 May 2007 }}</ref><ref>{{cite book |last=Taylor |first=Kathleen Eleanor |author-link=Kathleen Taylor (biologist) |title=Brainwashing: The Science of Thought Control |url=https://books.google.com/books?id=BIuju20yhDkC |access-date=2009-07-30 |date=December 2004 |publisher=Oxford University Press |isbn=978-0-19-280496-9 |page=215}}</ref>\n\nSome scholars have said that modern [[business corporation]]s practice mind control to create a work force that shares common values and culture.<ref>''Exploring Leadership: Individual, Organizational, and Societal Perspectives'', Richard Bolden, Beverley Hawkins, Jonathan Gosling, Scott Taylor, Oxford University Press, 30 June 2011, page 95.</ref> They have linked "corporate brainwashing" with [[globalization]], saying that corporations are attempting to create a worldwide [[Cultural homogenization|monocultural]] network of producers, consumers, and managers.<ref>''The Rise of the Anti-corporate Movement: Corporations and the People who Hate Them'', Evan Osborne, Greenwood Publishing Group, 2007, page 14</ref> Modern educational systems have also been criticized, by both the left and the right, for contributing to corporate brainwashing.<ref>''More Money Than Brains: Why School Sucks, College is Crap, & Idiots Think They're Right'', [[Laura Penny]], McClelland & Stewart, 20 April 2010, page 63.</ref> In his 1992 book, ''Democracy in an Age of Corporate Colonization'', [[Stanley A. Deetz]] says that modern "[[self awareness]]" and "[[self improvement]]" programs provide corporations with even more effective tools to control the minds of employees than traditional brainwashing was said to have been.<ref>''Democracy in an Age of Corporate Colonization: Developments in Communication and the Politics of Everyday Life'', Stanley Deetz, SUNY Press, 1 January 1992, page 257.</ref>"}},
{"article_title": "Nanotechnology", "pageid": "21488", "revid": "1059603745", "timestamp": "2021-12-10T13:00:53Z", "history_paths": [["Nanotechnology --- Introduction ---", "Origins"]], "categories": ["nanotechnology", "1960 introductions", "1985 introductions", "articles containing video clips", "emerging technologies", "1986 neologisms", "1970s neologisms"], "heading_tree": {"Nanotechnology --- Introduction ---": {"Origins": {}, "Fundamental concepts": {"Larger to smaller: a materials perspective": {}, "Simple to complex: a molecular perspective": {}, "Molecular nanotechnology: a long-term view": {}}, "Current research": {"Nanomaterials": {}, "Bottom-up approaches": {}, "Top-down approaches": {}, "Functional approaches": {}, "Biomimetic approaches": {}, "Speculative": {}, "Dimensionality in nanomaterials": {}}, "Tools and techniques": {}, "Research and development": {}, "Applications": {"Nanoelectronics": {}}, "Implications": {"Health and environmental concerns": {}}, "Regulation": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Nanotechnology --- Introduction ---|Origins": "{{Main|History of nanotechnology}}\nThe concepts that seeded nanotechnology were first discussed in 1959 by renowned physicist [[Richard Feynman]] in his talk ''[[There's Plenty of Room at the Bottom]]'', in which he described the possibility of synthesis via direct manipulation of atoms.\n\n[[File:Comparison of nanomaterials sizes.jpg|thumb|upright=1.8|right|Comparison of Nanomaterials Sizes]]\n\nThe term "nano-technology" was first used by [[Norio Taniguchi]] in 1974, though it was not widely known. Inspired by Feynman's concepts, [[K. Eric Drexler]] used the term "nanotechnology" in his 1986 book ''[[Engines of creation|Engines of Creation: The Coming Era of Nanotechnology]]'', which proposed the idea of a nanoscale "assembler" which would be able to build a copy of itself and of other items of arbitrary complexity with atomic control. Also in 1986, Drexler co-founded [[The Foresight Institute]] (with which he is no longer affiliated) to help increase public awareness and understanding of nanotechnology concepts and implications.\n\nThe emergence of nanotechnology as a field in the 1980s occurred through convergence of Drexler's theoretical and public work, which developed and popularized a conceptual framework for nanotechnology, and high-visibility experimental advances that drew additional wide-scale attention to the prospects of atomic control of matter. In the 1980s, two major breakthroughs sparked the growth of nanotechnology in the modern era. First, the invention of the [[scanning tunneling microscope]] in 1981 which provided unprecedented visualization of individual atoms and bonds, and was successfully used to manipulate individual atoms in 1989. The microscope's developers [[Gerd Binnig]] and [[Heinrich Rohrer]] at [[IBM Zurich Research Laboratory]] received a [[Nobel Prize in Physics]] in 1986.<ref name="Binnig">{{Cite journal|first1=G. |last1=Binnig |first2=H. |last2=Rohrer|title=Scanning tunneling microscopy|journal=IBM Journal of Research and Development|volume=30|issue=4|year=1986|pages=355\u201369}}</ref><ref>{{cite web|title=Press Release: the 1986 Nobel Prize in Physics|url=http://nobelprize.org/nobel_prizes/physics/laureates/1986/press.html|publisher=Nobelprize.org|access-date=12 May 2011|date=15 October 1986|url-status=live|archive-url=https://web.archive.org/web/20110605005907/http://nobelprize.org/nobel_prizes/physics/laureates/1986/press.html|archive-date=5 June 2011}}</ref> Binnig, [[Calvin F. Quate|Quate]] and Gerber also invented the analogous [[atomic force microscope]] that year.\n\n[[File:C60a.png|thumb|upright=0.8|left|Buckminsterfullerene C<sub>60</sub>, also known as the [[buckyball]], is a representative member of the [[Allotropes of carbon|carbon structures]] known as [[fullerene]]s. Members of the fullerene family are a major subject of research falling under the nanotechnology umbrella.]]\n\nSecond, [[fullerenes]] were discovered in 1985 by [[Harry Kroto]], [[Richard Smalley]], and [[Robert Curl]], who together won the 1996 [[Nobel Prize in Chemistry]].<ref>{{Cite journal | doi = 10.1038/318162a0| title = C<sub>60</sub>: Buckminsterfullerene| journal = Nature| volume = 318| issue = 6042| pages = 162\u2013163| year = 1985| last1 = Kroto | first1 = H. W.| last2 = Heath | first2 = J. R.| last3 = O'Brien | first3 = S. C.| last4 = Curl | first4 = R. F.| last5 = Smalley | first5 = R. E.| s2cid = 4314237| bibcode = 1985Natur.318..162K}}</ref><ref>{{Cite journal | last1 = Adams | first1 = W. W. | last2 = Baughman | first2 = R. H. | doi = 10.1126/science.1122120 | title = RETROSPECTIVE: Richard E. Smalley (1943-2005) | journal = Science | volume = 310 | issue = 5756 | page = 1916 | year = 2005 | pmid = 16373566| doi-access = free }}</ref> C<sub>60</sub> was not initially described as nanotechnology; the term was used regarding subsequent work with related [[carbon nanotube]]s (sometimes called [[graphene]] tubes or Bucky tubes) which suggested potential applications for nanoscale electronics and devices. The discovery of [[carbon nanotubes]] is largely attributed to [[Sumio Iijima]] of [[NEC]] in 1991,<ref name="carbon">{{Cite journal|title=Who should be given the credit for the discovery of carbon nanotubes?|doi=10.1016/j.carbon.2006.03.019|first1=Marc|last1=Monthioux|journal=Carbon|volume=44|year=2006|url=http://www.cemes.fr/fichpdf/GuestEditorial.pdf |pages=1621\u20131623|last2=Kuznetsov|first2=V|issue=9}}</ref> for which Iijima won the inaugural 2008 [[Kavli Prize]] in Nanoscience.\n\nA nanolayer-base [[metal\u2013semiconductor junction]] (M\u2013S junction) [[transistor]] was initially proposed by A. Rose in 1960, and [[Semiconductor device fabrication|fabricated]] by L. Geppert, [[Mohamed Atalla]] and [[Dawon Kahng]] in 1962.<ref>{{cite book |last1=Pasa |first1=Andr\u00e9 Avelino |chapter=Chapter 13: Metal Nanolayer-Base Transistor |title=Handbook of Nanophysics: Nanoelectronics and Nanophotonics |date=2010 |publisher=[[CRC Press]] |isbn=9781420075519 |pages=13-1, 13-4 |chapter-url=https://books.google.com/books?id=a3kJAMALo0MC&pg=SA13-PA1}}</ref> Decades later, advances in [[multi-gate]] technology enabled the [[MOSFET scaling|scaling]] of [[metal\u2013oxide\u2013semiconductor field-effect transistor]] (MOSFET) devices down to [[List of semiconductor scale examples|nano-scale]] levels smaller than [[20 nm]] gate length, starting with the [[FinFET]] (fin field-effect transistor), a three-dimensional, non-planar, double-gate MOSFET. At [[University of California, Berkeley|UC Berkeley]], a team of researchers including Digh Hisamoto, [[Chenming Hu]], [[Tsu-Jae King Liu]], Jeffrey Bokor and others fabricated FinFET devices down to a [[16 nanometer|17{{nbsp}}nm]] process in 1998, then [[16 nanometer|15{{nbsp}}nm]] in 2001, and then [[10 nanometer|10{{nbsp}}nm]] in 2002.<ref name="Liu">{{cite web |last1=Tsu\u2010Jae King |first1=Liu |author-link1=Tsu-Jae King Liu |title=FinFET: History, Fundamentals and Future |url=https://people.eecs.berkeley.edu/~tking/presentations/KingLiu_2012VLSI-Tshortcourse |website=[[University of California, Berkeley]] |publisher=Symposium on VLSI Technology Short Course |date=June 11, 2012 |access-date=9 July 2019}}</ref>\n\nIn the early 2000s, the field garnered increased scientific, political, and commercial attention that led to both controversy and progress. Controversies emerged regarding the definitions and potential implications of nanotechnologies, exemplified by the [[Royal Society]]'s report on nanotechnology.<ref name="royalsociety">{{cite web |publisher=Royal Society and Royal Academy of Engineering |title=Nanoscience and nanotechnologies: opportunities and uncertainties |date=July 2004 |url=http://www.nanotec.org.uk/finalReport.htm |access-date=13 May 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110526060835/http://www.nanotec.org.uk/finalReport.htm |archive-date=26 May 2011 }}</ref> Challenges were raised regarding the feasibility of applications envisioned by advocates of molecular nanotechnology, which culminated in a public debate between Drexler and Smalley in 2001 and 2003.<ref name="counterpoint">{{cite journal |url=http://pubs.acs.org/cen/coverstory/8148/8148counterpoint.html |title=Nanotechnology: Drexler and Smalley make the case for and against 'molecular assemblers' |journal=Chemical & Engineering News |volume=81 |issue=48 |pages=37\u201342 |date=1 December 2003 |access-date=9 May 2010 |doi=10.1021/cen-v081n036.p037|doi-access=free }}</ref>\n\nMeanwhile, commercialization of products based on advancements in nanoscale technologies began emerging. These products are limited to bulk applications of [[nanomaterials]] and do not involve atomic control of matter. Some examples include the [[Silver Nano]] platform for using [[silver nanoparticles]] as an antibacterial agent, [[nanoparticle]]-based transparent sunscreens, [[Carbon fibers|carbon fiber]] strengthening using silica nanoparticles, and carbon nanotubes for stain-resistant textiles.<ref name="americanelements">{{cite web|title=Nanotechnology Information Center: Properties, Applications, Research, and Safety Guidelines|url=http://www.americanelements.com/nanomaterials-nanoparticles-nanotechnology.html|publisher=[[American Elements]]|access-date=13 May 2011|url-status=live|archive-url=https://web.archive.org/web/20141226011154/http://www.americanelements.com/nanomaterials-nanoparticles-nanotechnology.html|archive-date=26 December 2014}}</ref><ref name="emergingnano">{{cite web |year=2008 |url=http://www.nanotechproject.org/inventories/consumer/analysis_draft/ |publisher=The Project on Emerging Nanotechnologies |title=Analysis: This is the first publicly available on-line inventory of nanotechnology-based consumer products |access-date=13 May 2011 |url-status=live |archive-url=https://web.archive.org/web/20110505011238/http://www.nanotechproject.org/inventories/consumer/analysis_draft/ |archive-date=5 May 2011 }}</ref>\n\nGovernments moved to promote and [[Funding of science|fund research]] into nanotechnology, such as in the U.S. with the [[National Nanotechnology Initiative]], which formalized a size-based definition of nanotechnology and established funding for research on the nanoscale, and in Europe via the European [[Framework Programmes for Research and Technological Development]].\n\nBy the mid-2000s new and serious scientific attention began to flourish.  Projects emerged to produce nanotechnology roadmaps<ref name=PNRoadmap>{{cite web|title=Productive Nanosystems Technology Roadmap|url=http://www.productivenanosystems.com/docs/Nanotech_Roadmap_2007_main.pdf|url-status=live|archive-url=https://web.archive.org/web/20130908014630/http://www.productivenanosystems.com/docs/Nanotech_Roadmap_2007_main.pdf|archive-date=2013-09-08}}</ref><ref name=NASAroadmap>{{cite web|title=NASA Draft Nanotechnology Roadmap|url=http://www.nasa.gov/pdf/501325main_TA10-Nanotech-DRAFT-Nov2010-A.pdf|url-status=live|archive-url=https://web.archive.org/web/20130122114146/http://www.nasa.gov/pdf/501325main_TA10-Nanotech-DRAFT-Nov2010-A.pdf|archive-date=2013-01-22}}</ref>  which center on atomically precise manipulation of matter and discuss existing and projected capabilities, goals, and applications.\n\nIn 2006, a team of Korean researchers from the [[KAIST|Korea Advanced Institute of Science and Technology]] (KAIST) and the National Nano Fab Center developed a [[3 nm]] MOSFET, the world's smallest [[nanoelectronic]] device. It was based on [[gate-all-around]] (GAA) FinFET technology.<ref>{{citation |url=http://www.highbeam.com/doc/1G1-145838158.html|archive-url=https://web.archive.org/web/20121106011401/http://www.highbeam.com/doc/1G1-145838158.html|url-status=dead|archive-date=6 November 2012|title=Still Room at the Bottom (nanometer transistor developed by Yang-kyu Choi from the Korea Advanced Institute of Science and Technology)|date=1 April 2006|work = Nanoparticle News }}</ref><ref>{{citation |first=Hyunjin |last=Lee |s2cid=26482358 |year=2006 |title=Sub-5nm All-Around Gate FinFET for Ultimate Scaling |journal=Symposium on VLSI Technology, 2006 |pages=58\u201359 |doi=10.1109/VLSIT.2006.1705215 |display-authors=etal|isbn=978-1-4244-0005-8 |hdl=10203/698 |hdl-access=free }}</ref>\n\nOver sixty countries created nanotechnology [[research and development]] (R&D) government programs between 2001 and 2004. Government funding was exceeded by corporate spending on nanotechnology R&D, with most of the funding coming from corporations based in the United States, Japan and Germany. The top five organizations that filed the most intellectual [[patent]]s on nanotechnology R&D between 1970 and 2011 were [[Samsung Electronics]] (2,578 first patents), [[Nippon Steel]] (1,490 first patents), [[IBM]] (1,360 first patents), [[Toshiba]] (1,298 first patents) and [[Canon Inc.|Canon]] (1,162 first patents). The top five organizations that published the most scientific papers on nanotechnology research between 1970 and 2012 were the [[Chinese Academy of Sciences]], [[Russian Academy of Sciences]], [[Centre national de la recherche scientifique]], [[University of Tokyo]] and [[Osaka University]].<ref name="wipo"/>"}},
{"article_title": "Nanoengineering", "pageid": "21561", "revid": "1021871027", "timestamp": "2021-05-07T04:08:17Z", "history_paths": [["Nanoengineering --- Introduction ---", "History"]], "categories": ["nanotechnology", "engineering disciplines"], "heading_tree": {"Nanoengineering --- Introduction ---": {"History": {}, "Degree programs": {}, "Techniques": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Nanoengineering --- Introduction ---|History": "* 4th Century Rome: The Lycurgus Cup was crafted using [[dichroic glass]] which is a product of nanoengineering\n* 6th-15th Centuries: Stained glass windows were created in European cathedrals which contained nanoparticles of gold chloride or other metal oxides or chlorides. These nanoparticles give the glass its vibrant colors.\n* 9th-17th Centuries: A sparkling layer on the outside of ceramics was used containing silver, copper, or other metallic nanoparticles.\n* 13th-18th Centuries: "Damascus" saber blades were crafted using techniques that resulted in nanotubes and cementite nanowires.\n* 1950: Victor La Mer and Robert Dinegar created a process that was used to create specialized papers, paints, and thin films on an industrial level by growing monodisperse colloidal materials.\n* 1959: Richard Feynman gave the first lecture on molecular technology and engineering or just nanoengineering.\n* 1981: Gerd Binnig and Heinrich Rohrer invented the first atomic level microscope called a [[scanning tunneling microscope]] that allowed scientists to see individual atoms\n* 1991: The [[carbon nanotube]] was discovered by [[Sumio Iijima]] which became important due to their strength, and electrical and [[thermal conductivity]]\n* 2004: SUNY Albany started the first college program that focused on nanoengineering in the United States. It was called the College of Nanoscale Science and Engineering\n* 2009-2010: Robotic nanoscale assembly devices were created by Nadrian Seeman and his colleagues. These devices would be used to create 3D DNA structures using DNA crystals<ref>{{Cite web|url=https://www.nano.gov/timeline|title=Nanotechnology Timeline {{!}} Nano|website=www.nano.gov|access-date=2019-03-17}}</ref>"}},
{"article_title": "Nuclear reactor", "pageid": "22151", "revid": "1062090947", "timestamp": "2021-12-26T06:08:01Z", "history_paths": [["Nuclear reactor --- Introduction ---", "Early reactors"], ["Nuclear reactor --- Introduction ---", "Reactor types"]], "categories": ["energy conversion", "nuclear technology", "power station technology", "nuclear reactors", "pressure vessels", "nuclear research reactors", "nuclear power reactor types", "neutron sources"], "heading_tree": {"Nuclear reactor --- Introduction ---": {"Operation": {"Fission": {}, "Heat generation": {}, "Cooling": {}, "Reactivity control": {}, "Electrical power generation": {}}, "Early reactors": {}, "Reactor types": {"Classifications": {"By type of nuclear reaction": {}, "By moderator material": {}, "By coolant": {}, "By generation": {}, "By phase of fuel": {}, "By shape of the core": {}, "By use": {}}, "Current technologies": {}, "Future and developing technologies": {"Advanced reactors": {}, "Generation IV reactors": {}, "Generation V+ reactors": {}, "Fusion reactors": {}}}, "Nuclear fuel cycle": {"Fueling of nuclear reactors": {}}, "Nuclear safety": {}, "Nuclear accidents": {}, "Natural nuclear reactors": {}, "Emissions": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Nuclear reactor --- Introduction ---|Early reactors": "{{See also|Nuclear fission#History}}\n[[File:Stagg Field reactor.jpg|thumb|The [[Chicago Pile-1|Chicago Pile]], the first nuclear reactor, built in secrecy at the University of Chicago in 1942 during World War II as part of the US's [[Manhattan project]]. ]]\n[[File:Otto Hahn und Lise Meitner.jpg|thumb|upright=0.75|[[Lise Meitner]] and [[Otto Hahn]] in their laboratory.]]\n[[File:ChicagoPileTeam.png|right|thumb|Some of the [[Chicago Pile-1|Chicago Pile Team]], including [[Enrico Fermi]] and [[Le\u00f3 Szil\u00e1rd]].]]\nThe [[neutron]] was discovered in 1932 by British physicist [[James Chadwick]]. The concept of a nuclear chain reaction brought about by [[nuclear reaction]]s mediated by neutrons was first realized shortly thereafter, by [[Hungary|Hungarian]] scientist [[Le\u00f3 Szil\u00e1rd]], in 1933. He filed a patent for his idea of a simple reactor the following year while working at the [[British Admiralty|Admiralty]] in London.<ref>L. Szil\u00e1rd, [http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=GB630726 "Improvements in or relating to the transmutation of chemical elements,"] British patent number: GB630726 (filed: 28 June 1934; published: 30 March 1936).</ref> However, Szil\u00e1rd's idea did not incorporate the idea of nuclear fission as a neutron source, since that process was not yet discovered. Szil\u00e1rd's ideas for nuclear reactors using neutron-mediated nuclear chain reactions in light elements proved unworkable.\n\nInspiration for a new type of reactor using uranium came from the discovery by [[Lise Meitner]], [[Fritz Strassmann]] and [[Otto Hahn]] in 1938 that bombardment of uranium with neutrons (provided by an alpha-on-beryllium fusion reaction, a "[[neutron howitzer]]") produced a [[barium]] residue, which they reasoned was created by the fissioning of the uranium nuclei. Subsequent studies in early 1939 (one of them by Szil\u00e1rd and Fermi) revealed that several neutrons were also released during the fissioning, making available the opportunity for the nuclear [[chain reaction]] that Szil\u00e1rd had envisioned six years previously.\n\nOn 2 August 1939 [[Albert Einstein]] signed a letter to President [[Franklin D. Roosevelt]] (written by Szil\u00e1rd) suggesting that the discovery of uranium's fission could lead to the development of "extremely powerful bombs of a new type", giving impetus to the study of reactors and fission. Szil\u00e1rd and Einstein knew each other well and had worked together years previously, but Einstein had never thought about this possibility for nuclear energy until Szilard reported it to him, at the beginning of his quest to produce the [[Einstein-Szil\u00e1rd letter]] to alert the U.S. government.\n\nShortly after, [[Hitler]]'s Germany invaded Poland in 1939, starting [[World War II]] in Europe. The U.S. was not yet officially at war, but in October, when the Einstein-Szil\u00e1rd letter was delivered to him, Roosevelt commented that the purpose of doing the research was to make sure "the Nazis don't blow us up." The U.S. nuclear project followed, although with some delay as there remained skepticism (some of it from Fermi) and also little action from the small number of officials in the government who were initially charged with moving the project forward.\n\nThe following year the U.S. Government received the [[Frisch\u2013Peierls memorandum]] from the UK, which stated that the amount of [[uranium]] needed for a [[chain reaction]] was far lower than had previously been thought. The memorandum was a product of the [[MAUD Committee]], which was working on the UK atomic bomb project, known as [[Tube Alloys]], later [[British contribution to the Manhattan Project|to be subsumed]] within the [[Manhattan Project]].\n\nEventually, the first artificial nuclear reactor, [[Chicago Pile-1]], was constructed at the [[University of Chicago]], by a team led by [[Italians|Italian]] physicist [[Enrico Fermi]], in late 1942. By this time, the program had been pressured for a year by U.S. entry into the war. The Chicago Pile achieved [[critical mass|criticality]] on 2 December 1942<ref>The First Reactor, U.S. Atomic Energy Commission, Division of Technical Information</ref> at 3:25 PM. The reactor support structure was made of wood, which supported a pile (hence the name) of graphite blocks, embedded in which was natural uranium oxide 'pseudospheres' or 'briquettes'.\n\nSoon after the Chicago Pile, the U.S. military developed a number of nuclear reactors for the [[Manhattan Project]] starting in 1943. The primary purpose for the largest reactors (located at the [[Hanford Site]] in [[Washington (state)|Washington]]), was the mass production of [[plutonium]] for nuclear weapons. Fermi and Szilard applied for a patent on reactors on 19 December 1944. Its issuance was delayed for 10 years because of wartime secrecy.<ref>Enrico, Fermi and Leo, Szilard {{US Patent|2708656}} "Neutronic Reactor" issued 17 May 1955</ref>\n\n"World's first nuclear power plant" is the claim made by signs at the site of the [[EBR-I]], which is now a museum near [[Arco, Idaho]]. Originally called "Chicago Pile-4", it was carried out under the direction of [[Walter Zinn]] for [[Argonne National Laboratory]].<ref>{{cite web|url=http://www.ne.anl.gov/About/hn/news960320.shtml|title=Chicago Pile reactors create enduring research legacy \u2013 Argonne's Historical News Releases|work=anl.gov}}</ref> This experimental [[LMFBR]] operated by the [[U.S. Atomic Energy Commission]] produced 0.8 kW in a test on 20 December 1951<ref>[https://inlportal.inl.gov/portal/server.pt/gateway/PTARGS_0_200_816_259_0_43/http%3B/inlpublisher%3B7087/publishedcontent/publish/communities/inl_gov/about_inl/home_page_fact_sheets/sheets/experimental_breeder_reactor___i_4.pdf Experimental Breeder Reactor 1 factsheet], Idaho National Laboratory {{webarchive |url=https://web.archive.org/web/20081029200744/https://inlportal.inl.gov/portal/server.pt/gateway/PTARGS_0_200_816_259_0_43/http%3B/inlpublisher%3B7087/publishedcontent/publish/communities/inl_gov/about_inl/home_page_fact_sheets/sheets/experimental_breeder_reactor___i_4.pdf |date=29 October 2008 }}</ref> and 100 kW (electrical) the following day,<ref>{{cite web | url=http://www.ans.org/pubs/magazines/nn/docs/2001-11-2.pdf | title=Fifty years ago in December: Atomic reactor EBR-I produced first electricity | publisher=American Nuclear Society Nuclear news | date=November 2001 | access-date=18 June 2008 | archive-url=https://web.archive.org/web/20080625035749/http://www.ans.org/pubs/magazines/nn/docs/2001-11-2.pdf | archive-date=25 June 2008 | url-status=dead }}</ref> having a design output of 200 kW (electrical).\n\nBesides the military uses of nuclear reactors, there were political reasons to pursue civilian use of atomic energy. U.S. President [[Dwight Eisenhower]] made his famous [[Atoms for Peace]] speech to the [[UN General Assembly]] on 8 December 1953. This diplomacy led to the dissemination of reactor technology to U.S. institutions and worldwide.<ref>{{Cite web|url=https://www.pbs.org/wgbh/nova/tech/the-nuclear-option.html|title=The Nuclear Option \u2014 NOVA {{!}} PBS|website=www.pbs.org|access-date=2017-01-12}}</ref>\n\nThe first nuclear power plant built for civil purposes was the AM-1 [[Obninsk Nuclear Power Plant]], launched on 27 June 1954 in the [[Soviet Union]]. It produced around 5 MW (electrical). It was built after the [[F-1 (nuclear reactor)]] which was the first reactor to go critical in Europe, and was also built by the Soviet Union.\n\nAfter World War II, the U.S. military sought other uses for nuclear reactor technology. Research by the Army led to the power stations for Camp Century, Greenland and McMurdo Station, Antarctica [[Army Nuclear Power Program]]. The Air Force Nuclear Bomber project resulted in the [[Molten-Salt Reactor Experiment]]. The U.S. Navy succeeded when they steamed the [[USS Nautilus (SSN-571)|USS ''Nautilus'']] (SSN-571) on nuclear power 17 January 1955.\n\nThe first commercial nuclear power station, [[Calder Hall nuclear power station|Calder Hall]] in [[Sellafield]], England was opened in 1956 with an initial capacity of 50 MW (later 200 MW).<ref name=Kragh>{{cite book |last=Kragh|first=Helge |title=Quantum Generations: A History of Physics in the Twentieth Century |url=https://archive.org/details/quantumgeneratio0000krag|url-access=registration|publisher=Princeton University Press |location=Princeton NJ |year=1999 |page=[https://archive.org/details/quantumgeneratio0000krag/page/286 286] |isbn=0-691-09552-3}}</ref><ref name="bbc17oct">{{cite news |url= http://news.bbc.co.uk/onthisday/hi/dates/stories/october/17/newsid_3147000/3147145.stm |title=On This Day: 17 October|access-date=9 November 2006 |work=BBC News | date=17 October 1956}}</ref>\n\nThe first portable nuclear reactor "Alco PM-2A" was used to generate electrical power (2 MW) for [[Camp Century]] from 1960 to 1963.<ref>{{cite web | url=http://gombessa.tripod.com/scienceleadstheway/id9.html | title=Science Leads the Way | publisher=Camp Century, Greenland | first=Frank J. | last=Leskovitz}}</ref>\n\n[[File:HPR1000, reactor coolant system.png|thumb|Primary coolant system showing [[reactor pressure vessel]] (red), [[Steam generator (nuclear power)|steam generators]] (purple), [[pressurizer]] (blue), and pumps (green) in the three coolant loop [[Hualong One]] [[pressurized water reactor]] design]]", "Nuclear reactor --- Introduction ---|Reactor types": "{{image frame\n|width=210\n|caption=Number of reactors by type (end 2014)<ref name="IAEA_reactors_stats">{{cite web|title=Nuclear Power Reactors in the World \u2013 2015 Edition|url=http://www-pub.iaea.org/MTCD/Publications/PDF/rds2-35web-85937611.pdf|publisher=International Atomic Energy Agency (IAEA)|access-date=26 October 2017}}</ref>\n|content=<div style="text-align:left">\n{{#invoke:Chart|pie chart\n| radius = 100\n| slices = \n    ( 277 : PWR : : [[Pressurized Water Reactor]]) \n    ( 80 : BWR : : [[Boiling Water Reactor]] ) \n    ( 15 : GCR : : [[Gas Cooled Reactor]] ) \n    ( 49 : PHWR : : [[Pressurized Heavy Water Reactor]] )\n    ( 15 : LWGR : : [[LWGR]] )\n    ( 2 : FBR : : [[Fast Breeder Reactor]] )\n| units suffix = \n| percent = true\n}}</div>\n}}\n{{image frame\n|width=210\n|caption=Net power capacity (GWe) by type (end 2014)<ref name="IAEA_reactors_stats" />\n|content=<div style="text-align:left">\n{{#invoke:Chart|pie chart\n| radius = 100\n| slices = \n    ( 257.2: PWR : : [[Pressurized Water Reactor]]) \n    ( 75.5 : BWR : : [[Boiling Water Reactor]]  ) \n    ( 8.2 : GCR : : [[Gas Cooled Reactor]] ) \n    ( 24.6 : PHWR : : [[Pressurized Heavy Water Reactor]] )\n    ( 10.2 : LWGR  : : [[LWGR]] )\n    ( 0.6 : FBR  : : [[Fast Breeder Reactor]] )\n| units suffix = \n| percent = true\n}}</div>\n}}\n\n[[File:Pulstar2.jpg|thumb|upright|[[North Carolina State University|NC State]]'s PULSTAR Reactor is a 1 MW pool-type [[research reactor]] with 4% enriched, pin-type fuel consisting of '''UO<sub>2</sub>''' pellets in [[zircaloy]] cladding.]]\n\n \n \nAll commercial power reactors are based on [[nuclear fission]]. They generally use [[uranium]] and its product [[plutonium]] as [[nuclear fuel]], though a [[thorium fuel cycle]] is also possible. Fission reactors can be divided roughly into two classes, depending on the energy of the neutrons that sustain the fission [[chain reaction]]:\n* [[Thermal reactor|Thermal neutron reactor]]s (the most common type of nuclear reactor) use slowed or [[thermal neutron]]s to keep up the fission of their fuel. Almost all current reactors are of this type. These contain [[neutron moderator]] materials that slow neutrons until their [[neutron temperature]] is ''thermalized'', that is, until their [[kinetic energy]] approaches the average kinetic energy of the surrounding particles. Thermal neutrons have a far higher [[Nuclear cross section|cross section]] (probability) of fissioning the [[fissile]] nuclei [[uranium-235]], [[plutonium-239]], and [[plutonium-241]], and a relatively lower probability of [[neutron capture]] by [[uranium-238]] (U-238) compared to the faster neutrons that originally result from fission, allowing use of [[low-enriched uranium]] or even [[natural uranium]] fuel. The moderator is often also the [[coolant]], usually water under high pressure to increase the [[boiling point]]. These are surrounded by a [[reactor vessel]], instrumentation to monitor and control the reactor, [[radiation shielding]], and a [[containment building]].\n* [[Fast neutron reactor]]s use [[fast neutron]]s to cause fission in their fuel. They do not have a [[neutron moderator]], and use less-moderating coolants. Maintaining a chain reaction requires the fuel to be more highly [[isotope separation|enriched]] in [[fissile]] material (about 20% or more) due to the relatively lower probability of fission versus capture by U-238. Fast reactors have the potential to produce less [[transuranic]] waste because all [[actinides]] are fissionable with fast neutrons,<ref>{{Cite journal | doi = 10.1007/BF00750983| title = Fast-reactor actinoid transmutation| journal = Atomic Energy| volume = 74| page = 83| year = 1993| last1 = Golubev | first1 = V. I.| last2 = Dolgov | first2 = V. V.| last3 = Dulin | first3 = V. A.| last4 = Zvonarev | first4 = A. V.| last5 = Smetanin | first5 = \u00c9. Y. | last6 = Kochetkov | first6 = L. A.| last7 = Korobeinikov | first7 = V. V.| last8 = Liforov | first8 = V. G.| last9 = Manturov | first9 = G. N.| last10 = Matveenko | first10 = I. P.| last11 = Tsibulya | first11 = A. M.| s2cid = 95704617}}</ref> but they are more difficult to build and more expensive to operate. Overall, fast reactors are less common than thermal reactors in most applications. Some early power stations were fast reactors, as are some Russian naval propulsion units. Construction of prototypes is continuing (see [[fast breeder]] or [[Generation IV reactor#Fast reactors|generation IV reactors]]).\n\nIn principle, [[fusion power]] could be produced by [[nuclear fusion]] of elements such as the [[deuterium]] isotope of [[hydrogen]].  While an ongoing rich research topic since at least the 1940s, no self-sustaining fusion reactor for any purpose has ever been built.\n\n Used by thermal reactors:\n* [[Graphite-moderated reactor]]s\n* Water moderated reactors\n**[[Heavy-water reactor]]s (Used in Canada,<ref name="hyperphysics">{{cite web|last1=Nave|first1=R|title=Light Water Nuclear Reactors|url=http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/ligwat.html |website=Hyperphysics |publisher = Georgia State University|access-date=5 March 2018}}</ref> India, Argentina, China, Pakistan, Romania and South Korea).<ref>{{Cite book|last=Joyce|first=Malcolm|date=2018|title=Nuclear Engineering|publisher=Elsevier|chapter=10.6|doi=10.1016/c2015-0-05557-5|isbn=9780081009628}}</ref>\n** [[Light-water reactor|Light-water-moderated reactors]] (LWRs). Light-water reactors (the most common type of thermal reactor) use ordinary water to moderate and cool the reactors.<ref name ="hyperphysics"/> Because the light hydrogen isotope is a slight neutron poison these reactors need artificially enriched fuels. When at [[operating temperature]], if the temperature of the water increases, its density drops, and fewer neutrons passing through it are slowed enough to trigger further reactions. That [[negative feedback]] stabilizes the reaction rate. Graphite and heavy-water reactors tend to be more thoroughly thermalized than light water reactors. Due to the extra thermalization, and the absence of the light hydrogen poisoning effects these types can use [[natural uranium]]/unenriched fuel.\n* Light-element-moderated reactors.\n** [[Molten salt reactor]]s (MSRs) are moderated by light elements such as lithium or beryllium, which are constituents of the coolant/fuel matrix salts [[Lithium fluoride |"LiF"]] and [[Beryllium fluoride |"BeF<sub>2</sub>]]", [[Lithium chloride|"LiCh"]] and [[Beryllium chloride|"BeCh<sub>2</sub>]]" and other light element containing salts can all cause a moderating effect.\n** [[Liquid metal cooled reactor]]s, such as those whose coolant is a mixture of lead and bismuth, may use BeO as a moderator.\n* [[Organic nuclear reactor|Organically moderated reactors]] (OMR) use [[biphenyl]] and [[terphenyl]] as moderator and coolant.\n\n [[File:RIAN archive 450312 Treatment of interior part of reactor frame.jpg|thumb|Treatment of the interior part of a [[VVER|VVER-1000]] reactor frame at [[Atommash]].]]\n[[File:Thermal reactor diagram.png|thumb|In thermal nuclear reactors (LWRs in specific), the coolant acts as a moderator that must slow down the neutrons before they can be efficiently absorbed by the fuel.]]\n* Water cooled reactor. These constitute the great majority of operational nuclear reactors: as of 2014, 93% of the world's nuclear reactors are water cooled, providing about 95% of the world's total nuclear generation capacity.<ref name="IAEA_reactors_stats" />\n** [[Pressurized water reactor]] (PWR) Pressurized water reactors constitute the large majority of all Western nuclear power plants.\n*** A primary characteristic of PWRs is a pressurizer, a specialized [[pressure vessel]]. Most commercial PWRs and naval reactors use pressurizers. During normal operation, a pressurizer is partially filled with water, and a steam bubble is maintained above it by heating the water with submerged heaters. During normal operation, the pressurizer is connected to the primary reactor pressure vessel (RPV) and the pressurizer "bubble" provides an expansion space for changes in water volume in the reactor. This arrangement also provides a means of pressure control for the reactor by increasing or decreasing the steam pressure in the pressurizer using the pressurizer heaters.\n*** [[Pressurized heavy water reactor]]s are a subset of pressurized water reactors, sharing the use of a pressurized, isolated heat transport loop, but using [[heavy water]] as coolant and moderator for the greater neutron economies it offers.\n** [[Boiling water reactor]] (BWR)\n*** BWRs are characterized by boiling water around the fuel rods in the lower portion of a primary reactor pressure vessel. A boiling water reactor uses <sup>235</sup>U, enriched as uranium dioxide, as its fuel. The fuel is assembled into rods housed in a steel vessel that is submerged in water. The nuclear fission causes the water to boil, generating steam. This steam flows through pipes into turbines. The turbines are driven by the steam, and this process generates electricity.<ref name="nuclear_energy">{{cite web|last1=Lipper |first1=Ilan |first2=Jon |last2=Stone |url=http://www.umich.edu/~gs265/society/nuclear.htm |title=Nuclear Energy and Society |publisher=University of Michigan |access-date=3 October 2009 |url-status=dead |archive-url=https://web.archive.org/web/20090401172451/http://www.umich.edu/~gs265/society/nuclear.htm |archive-date=1 April 2009 }}</ref> During normal operation, pressure is controlled by the amount of steam flowing from the reactor pressure vessel to the turbine.\n** [[Supercritical water reactor]] (SCWR)\n*** SCWRs are a [[Generation IV reactor]] concept where the reactor is operated at supercritical pressures and water is heated to a supercritical fluid, which never undergoes a transition to steam yet behaves like saturated steam, to power a [[Steam generator (boiler)|steam generator]].\n** [[Reduced moderation water reactor]] [RWMR] which use more highly enriched fuel with the fuel elements set closer together to allow a faster neutron spectrum sometimes called an [[Epithermal neutron]] Spectrum.\n** Pool-type reactor can refer to unpressurized water cooled [[open pool reactor]]s,<ref>{{Cite web|url=https://www.ans.org/news/article-2066/pool-reactors-1-an-introduction/|title = Pool Reactors 1: An Introduction -- ANS / Nuclear Newswire}}</ref> but not to be confused with [[pool type LMFBR]]s which are sodium cooled\n** Some reactors have been cooled by [[heavy water]] which also served as a moderator. Examples include:\n***Early [[CANDU]] reactors (later ones use heavy water moderator but light water coolant)\n***[[DIDO (nuclear reactor)|DIDO]] class research reactors \n* [[Liquid metal cooled reactor]]. Since water is a moderator, it cannot be used as a coolant in a fast reactor. Liquid metal coolants have included [[sodium]], [[NaK]], lead, [[lead-bismuth eutectic]], and in early reactors, [[mercury (element)|mercury]].\n** [[Sodium-cooled fast reactor]]\n** [[Lead-cooled fast reactor]]\n* [[Gas cooled reactor]]s are cooled by a circulating gas.  In commercial nuclear power plants carbon dioxide has usually been used, for example in current British AGR nuclear power plants and formerly in a number of first generation British, French, Italian, & Japanese plants.   [[Nitrogen]]<ref>{{cite journal |title=Emergency and Back-Up Cooling of Nuclear Fuel and Reactors and Fire-Extinguishing, Explosion Prevention Using Liquid Nitrogen. |journal=USPTO Patent Applications |date=2018-05-24 |volume=Document number 20180144836 }}</ref> and helium  have also been used, helium being considered particularly suitable for high temperature designs.   Utilization of the heat varies, depending on the reactor.  Commercial nuclear power plants run the gas through a [[heat exchanger]] to make steam for a steam turbine.  Some experimental designs run hot enough that the gas can directly power a gas turbine.\n* [[Molten salt reactor]]s (MSRs) are cooled by circulating a molten salt, typically a eutectic mixture of fluoride salts, such as [[FLiBe]]. In a typical MSR, the coolant is also used as a matrix in which the fissile material is dissolved. Other eutectic salt combinations used include [[Zirconium tetrafluoride| "ZrF<sub>4</sub>"]] with [[Sodium Fluoride|"NaF"]] and [[Lithium chloride|"LiCh"]] with [[Beryllium chloride|"BeCh<sub>2</sub>"]]\n* [[Organic nuclear reactor]]s use organic fluids such as biphenyl and terphenyl as coolant rather than water.\n\n * Generation I reactor (early prototypes such as [[Shippingport Atomic Power Station]], research reactors, non-commercial power producing reactors)\n* [[Generation II reactor]] (most current [[nuclear power plant]]s, 1965\u20131996)\n* [[Generation III reactor]] (evolutionary improvements of existing designs, 1996\u20132016)\n*[[Generation III reactor#Generation III+ reactors|Generation III+ reactor]] (evolutionary development of Gen III reactors, offering improvements in safety over Gen III reactor designs, 2017\u20132021)<ref>{{Cite web|url=https://analysis.nuclearenergyinsider.com/russia-completes-worlds-first-gen-iii-reactor-china-start-five-reactors-2017|title=Russia completes world's first Gen III+ reactor; China to start up five reactors in 2017|date=8 February 2017|website=Nuclear Energy Insider|access-date=10 July 2019}}</ref>\n* [[Generation IV reactor]] (technologies still under development; unknown start date, possibly 2030)<ref>{{cite web|title=Generation IV Nuclear Reactors|url=http://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-power-reactors/generation-iv-nuclear-reactors.aspx|publisher=World Nuclear Association}}</ref>\n\nIn 2003, the French [[Commissariat \u00e0 l'\u00c9nergie Atomique]] (CEA) was the first to refer to "Gen II" types in ''Nucleonics Week''.<ref>''Nucleonics Week'', Vol. 44, No. 39; p. 7, 25 September 2003 Quote: "Etienne Pochon, CEA director of nuclear industry support, outlined EPR's improved performance and enhanced safety features compared to the advanced Generation II designs on which it was based."</ref>\n\nThe first mention of "Gen III" was in 2000, in conjunction with the launch of the [[Generation IV International Forum]] (GIF) plans.\n\n"Gen IV" was named in 2000, by the [[United States Department of Energy]] (DOE), for developing new plant types.<ref>{{cite web |url=http://www.euronuclear.org/info/generation-IV.htm |title=Generation IV |publisher=Euronuclear.org |access-date=18 March 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110317125012/http://www.euronuclear.org/info/generation-IV.htm |archive-date=17 March 2011 }}</ref>\n\n * Solid fueled\n* Fluid fueled\n** [[Aqueous homogeneous reactor]]\n** [[Molten salt reactor]]\n* [[Gaseous fission reactor|Gas fueled]] (theoretical)\n\n * Cubical\n* Cylindrical\n* Octagonal\n* Spherical\n* Slab\n* Annulus\n\n * Electricity\n** [[Nuclear power plant]]s including [[small modular reactor]]s\n* Propulsion, see [[nuclear propulsion]]\n** [[Nuclear marine propulsion]]\n** Various proposed forms of [[rocket propulsion]]\n* Other uses of heat\n** [[Desalination]]\n** Heat for domestic and industrial heating\n** [[Hydrogen production]] for use in a [[hydrogen economy]]\n* Production reactors for [[Nuclear transmutation|transmutation]] of elements\n** [[Breeder reactor]]s are capable of producing more [[fissile material]] than they consume during the fission chain reaction (by converting [[Fertile material|fertile]] U-238 to Pu-239, or Th-232 to U-233). Thus, a uranium breeder reactor, once running, can be refueled with [[natural uranium|natural]] or even [[depleted uranium]], and a thorium breeder reactor can be refueled with [[thorium]]; however, an initial stock of fissile material is required.<ref name="Gen4">{{cite web |url= http://www.gen-4.org/PDFs/GenIVRoadmap.pdf |title= A Technology Roadmap for Generation IV Nuclear Energy Systems |url-status= dead |archive-url= https://web.archive.org/web/20061005211316/http://www.gen-4.org/PDFs/GenIVRoadmap.pdf |archive-date= 5 October 2006 |df= dmy-all }} {{small|(4.33 MB)}}; see "Fuel Cycles and Sustainability"</ref>\n** Creating various [[radiation|radioactive]] [[isotope]]s, such as [[americium]] for use in [[smoke detector]]s, and cobalt-60, molybdenum-99 and others, used for imaging and medical treatment.\n** Production of materials for [[nuclear weapon]]s such as [[weapons-grade]] [[plutonium]]\n* Providing a source of [[neutron radiation]] (for example with the pulsed [[Godiva device]]) and [[positron radiation]]{{Clarify|date=March 2008|reason=Neither linked article mentions reactors used to generate positrons. Needs explanation.}} (e.g. [[neutron activation analysis]] and [[potassium-argon dating]]{{Clarify|date=March 2008}}<!-- how are reactors used for dating? Linked article makes no mention of positron sources -->)\n* [[Research reactor]]: Typically reactors used for research and training, materials testing, or the production of radioisotopes for medicine and industry. These are much smaller than power reactors or those propelling ships, and many are on university campuses. There are about 280 such reactors operating, in 56 countries. Some operate with high-enriched uranium fuel, and international efforts are underway to substitute low-enriched fuel.<ref>{{cite web | url=http://www.world-nuclear.org/info/inf61.htm | title=World Nuclear Association Information Brief -Research Reactors | url-status=dead | archive-url=https://web.archive.org/web/20061231105602/http://www.world-nuclear.org/info/inf61.htm | archive-date=31 December 2006 | df=dmy-all }}</ref>\n\n {{unreferenced section|date=June 2015}}\n[[File:Diablo canyon nuclear power plant.jpg|thumb|[[Diablo Canyon Power Plant|Diablo Canyon]] \u2014 a PWR]]\n* [[Pressurized water reactor]]s (PWR) [moderator: high-pressure water; coolant: high-pressure water]\n\n:: These reactors use a pressure vessel to contain the nuclear fuel, control rods, moderator, and coolant. The hot radioactive water that leaves the pressure vessel is looped through a steam generator, which in turn heats a secondary (nonradioactive) loop of water to steam that can run turbines. They represent the majority (around 80%) of current reactors. This is a [[thermal neutron]] reactor design, the newest of which are the Russian [[VVER-1200]], Japanese [[Advanced Pressurized Water Reactor]], American [[AP1000]], Chinese [[Hualong One|Hualong Pressurized Reactor]] and the Franco-German [[European Pressurized Reactor]]. All the [[United States Naval reactor]]s are of this type.\n* [[Boiling water reactor]]s (BWR) [moderator: low-pressure water; coolant: low-pressure water]\n\n:: A BWR is like a PWR without the steam generator. The lower pressure of its cooling water allows it to boil inside the pressure vessel, producing the steam that runs the turbines. Unlike a PWR, there is no primary and secondary loop. The thermal efficiency of these reactors can be higher, and they can be simpler, and even potentially more stable and safe. This is a thermal neutron reactor design, the newest of which are the [[Advanced Boiling Water Reactor]] and the [[Economic Simplified Boiling Water Reactor]].\n[[File:CANDU at Qinshan.jpg|thumb|The [[CANDU]] [[Qinshan Nuclear Power Plant]]]]\n* [[Pressurised heavy water reactor|Pressurized Heavy Water Reactor]] (PHWR) [moderator: high-pressure heavy water; coolant: high-pressure heavy water]\n\n:: A Canadian design (known as [[CANDU]]), very similar to PWRs but using [[heavy water]]. While heavy water is significantly more expensive than ordinary water, it has greater [[neutron economy]] (creates a higher number of thermal neutrons), allowing the reactor to operate without [[Isotope separation|fuel enrichment facilities]]. Instead of using a single large pressure vessel as in a PWR, the fuel is contained in hundreds of pressure tubes. These reactors are fueled with natural [[uranium]] and are thermal neutron reactor designs. PHWRs can be refueled while at full power, ([[online refueling]]) which makes them very efficient in their use of uranium (it allows for precise flux control in the core). CANDU PHWRs have been built in Canada, [[Argentina]], China, [[India]], [[Pakistan]], [[Romania]], and [[South Korea]]. India also operates a number of PHWRs, often termed 'CANDU derivatives', built after the Government of Canada halted nuclear dealings with India following the 1974 [[Smiling Buddha]] nuclear weapon test.\n:[[File:Elektrownia Ignalina.jpg|thumb|The [[Ignalina Nuclear Power Plant]] \u2014 a RBMK type (closed 2009)]]\n* Reaktor Bolshoy Moschnosti Kanalniy (High Power Channel Reactor) ([[RBMK]]) [moderator: graphite; coolant: high-pressure water]\n\n:: A Soviet design, RBMKs are in some respects similar to CANDU in that they are refuelable during power operation and employ a pressure tube design instead of a PWR-style pressure vessel. However, unlike CANDU they are very unstable and large, making [[containment building]]s for them expensive. A series of critical safety flaws have also been identified with the RBMK design, though some of these were corrected following the [[Chernobyl disaster]]. Their main attraction is their use of light water and unenriched uranium. As of 2021, 9 remain open, mostly due to safety improvements and help from international safety agencies such as the DOE. Despite these safety improvements, RBMK reactors are still considered one of the most dangerous reactor designs in use. RBMK reactors were deployed only in the former [[Soviet Union]].\n[[File:Sizewell A.jpg|thumb|The [[Magnox]] [[Sizewell A]] nuclear power station]]\n[[File:Torness Nuclear Power Station, Scotland.JPG|thumb|The [[Torness nuclear power station]] \u2014 an AGR]]\n* [[Gas-cooled reactor]] (GCR) and [[advanced gas-cooled reactor]] (AGR) [moderator: graphite; coolant: carbon dioxide]\n\n:: These designs an have a high thermal efficiency compared with PWRs due to higher operating temperatures. There are a number of operating reactors of this design, mostly in the United Kingdom, where the concept was developed. Older designs (i.e. [[Magnox]] stations) are either shut down or will be in the near future. However, the AGRs have an anticipated life of a further 10 to 20 years. This is a thermal neutron reactor design. Decommissioning costs can be high due to large volume of reactor core.\n* [[Breeder reactor|Liquid metal]] [[Fast breeder reactor#Fast breeder reactor|fast-breeder reactor]] (LMFBR) [moderator: none; coolant: liquid metal]\n[[File:Topaz nuclear reactor.jpg|thumb|right| Scaled \u2013 down model of [[TOPAZ nuclear reactor]]]]\n\n:: This totally unmoderated reactor design produces more fuel than it consumes. They are said to "breed" fuel, because they produce fissionable fuel during operation because of [[neutron capture]]. These reactors can function much like a PWR in terms of efficiency, and do not require much high-pressure containment, as the liquid metal does not need to be kept at high pressure, even at very high temperatures. These reactors are [[fast neutron]], not thermal neutron designs. These reactors come in two types:\n[[File:Superph\u00e9nix.jpg|thumb|The [[Superph\u00e9nix]], closed in 1998, was one of the few FBRs]]\n\n:::[[Lead-cooled fast reactor|Lead-cooled]]\n:::: Using lead as the liquid metal provides excellent radiation shielding, and allows for operation at very high temperatures. Also, lead is (mostly) transparent to neutrons, so fewer neutrons are lost in the coolant, and the coolant does not become radioactive. Unlike sodium, lead is mostly inert, so there is less risk of explosion or accident, but such large quantities of lead may be problematic from toxicology and disposal points of view. Often a reactor of this type would use a [[lead-bismuth eutectic]] mixture. In this case, the bismuth would present some minor radiation problems, as it is not quite as transparent to neutrons, and can be transmuted to a radioactive isotope more readily than lead. The Russian [[Alfa class submarine]] uses a lead-bismuth-cooled fast reactor as its main power plant.\n::: [[Sodium-cooled fast reactor|Sodium-cooled]]\n:::: Most LMFBRs are of this type. The [[TOPAZ nuclear reactor|TOPAZ]], [[BN-350]] and [[BN-600]] in USSR; [[Superph\u00e9nix]] in France; and [[Enrico Fermi Nuclear Generating Station|Fermi-I]] in the United States were reactors of this type. The sodium is relatively easy to obtain and work with, and it also manages to actually prevent corrosion on the various reactor parts immersed in it. However, sodium explodes violently when exposed to water, so care must be taken, but such explosions would not be more violent than (for example) a leak of superheated fluid from a pressurized-water reactor. The [[Monju Nuclear Power Plant|Monju reactor]] in Japan suffered a sodium leak in 1995 and could not be [[Monju Nuclear Power Plant#2010 Restart|restarted]] until May 2010. The [[EBR-I]], the first reactor to have a core meltdown, in 1955, was also a sodium-cooled reactor. \n* [[Pebble-bed reactor]]s (PBR) [moderator: graphite; coolant: helium]\n:: These use fuel molded into ceramic balls, and then circulate gas through the balls. The result is an efficient, low-maintenance, very safe reactor with inexpensive, standardized fuel. The prototype was the [[AVR reactor|AVR]] and the [[HTR-10]] is operating in China, where the [[HTR-PM]] is being developed. The HTR-PM is expected to be the first generation IV reactor to enter operation.<ref name="WNN2018">{{cite news|url=https://www.neimagazine.com/features/featurehtr-pm-making-dreams-come-true-7009889/|title=HTR-PM: Making dreams come true|work=Nuclear Engineering International}}</ref>\n*[[Molten salt reactor]]s (MSR) [moderator: graphite, or none for fast spectrum MSRs; coolant: molten salt mixture]\n::These dissolve the fuels in [[fluoride]] or [[chloride]] salts, or use such salts for coolant. MSRs potentially have many safety features, including the absence of high pressures or highly flammable components in the core.  They were initially designed for aircraft propulsion due to their high efficiency and high power density. One prototype, the [[Molten-Salt Reactor Experiment]], was built to confirm the feasibility of the [[Liquid fluoride thorium reactor]], a thermal spectrum reactor which would breed fissile uranium-233 fuel from thorium.\n* [[Aqueous homogeneous reactor]] (AHR) [moderator: high-pressure light or heavy water; coolant: high-pressure light or heavy water]\n\n:: These reactors use as fuel soluble nuclear salts (usually [[uranium sulfate]] or [[uranium nitrate]]) dissolved in water and mixed with the coolant and the moderator. As of April 2006, only five AHRs were in operation.<ref>{{Cite web|url=https://nucleus.iaea.org/RRDB/RR/ReactorSearch.aspx|title=RRDB Search|website=nucleus.iaea.org}}</ref>\n\n \n More than a dozen advanced reactor designs are in various stages of development.<ref name="UIC">{{cite web |title=Advanced Nuclear Power Reactors |publisher=[[World Nuclear Association]] |url= http://world-nuclear.org/info/inf08.html |access-date=29 January 2010}}</ref> Some are evolutionary from the [[pressurized water reactor|PWR]], [[boiling water reactor|BWR]] and [[Pressurised Heavy Water Reactor|PHWR]] designs above, some are more radical departures. The former include the [[advanced boiling water reactor]] (ABWR), two of which are now operating with others under construction, and the planned [[passively safe]] [[Economic Simplified Boiling Water Reactor]] (ESBWR) and [[AP1000]] units (see [[Nuclear Power 2010 Program]]).\n* The [[Integral fast reactor]] (IFR) was built, tested and evaluated during the 1980s and then retired under the Clinton administration in the 1990s due to nuclear non-proliferation policies of the administration. Recycling spent fuel is the core of its design and it therefore produces only a fraction of the waste of current reactors.<ref name="pbs">{{cite web |url= https://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html |title=Nuclear Reaction: Why Do Americans Fear Nuclear Power? |access-date=9 November 2006 |publisher=Public Broadcasting Service (PBS) |author=Till, Charles }}</ref>\n* The [[pebble-bed reactor]], a [[high-temperature gas-cooled reactor]] (HTGCR), is designed so high temperatures reduce power output by [[Doppler broadening]] of the fuel's neutron cross-section. It uses ceramic fuels so its safe operating temperatures exceed the power-reduction temperature range. Most designs are cooled by inert helium. Helium is not subject to steam explosions, resists neutron absorption leading to radioactivity, and does not dissolve contaminants that can become radioactive. Typical designs have more layers (up to 7) of passive containment than light water reactors (usually 3). A unique feature that may aid safety is that the fuel balls actually form the core's mechanism, and are replaced one by one as they age. The design of the fuel makes fuel reprocessing expensive.\n* The [[Small, sealed, transportable, autonomous reactor]] (SSTAR) is being primarily researched and developed in the US, intended as a fast breeder reactor that is passively safe and could be remotely shut down in case the suspicion arises that it is being tampered with.\n* The [[Clean and Environmentally Safe Advanced Reactor]] (CAESAR) is a nuclear reactor concept that uses steam as a moderator \u2013 this design is still in development.\n* The [[Reduced moderation water reactor]] builds upon the [[Advanced boiling water reactor]](ABWR) that is presently in use, it is not a complete fast reactor instead using mostly [[epithermal neutron]]s, which are between thermal and fast neutrons in speed.\n* The [[hydrogen-moderated self-regulating nuclear power module]] (HPM) is a reactor design emanating from the [[Los Alamos National Laboratory]] that uses [[uranium hydride]] as fuel.\n* [[Subcritical reactor]]s are designed to be safer and more stable, but pose a number of engineering and economic difficulties. One example is the [[Energy amplifier]].\n* Thorium-based reactors. It is possible to convert Thorium-232 into U-233 in reactors specially designed for the purpose. In this way, thorium, which is four times more abundant than uranium, can be used to breed U-233 nuclear fuel.<ref name=NASA>{{cite journal|last1=Juhasz|first1=Albert J.|last2=Rarick|first2=Richard A.|last3=Rangarajan|first3=Rajmohan|title=High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090038711.pdf|website=NASA|date=October 2009|access-date=27 October 2014}}</ref> U-233 is also believed to have favourable nuclear properties as compared to traditionally used U-235, including better neutron economy and lower production of long lived transuranic waste.\n** [[Advanced heavy-water reactor]] (AHWR)\u2014 A proposed heavy water moderated nuclear power reactor that will be the next generation design of the PHWR type. Under development in the [[Bhabha Atomic Research Centre]] (BARC), India.\n** [[KAMINI]] \u2014 A unique reactor using Uranium-233 isotope for fuel. Built in India by [[Bhabha Atomic Research Centre|BARC]] and Indira Gandhi Center for Atomic Research ([[IGCAR]]).\n** India is also planning to build fast breeder reactors using the thorium \u2013 Uranium-233 fuel cycle. The FBTR (Fast Breeder Test Reactor) in operation at [[Kalpakkam]] (India) uses Plutonium as a fuel and liquid sodium as a coolant.\n** China, which has control of the [[Cerro Impacto]] deposit, has a reactor and hopes to replace [[coal energy]] with nuclear energy.<ref name=sch>{{Cite web|url=https://supchina.com/2019/01/14/venezuela-china-explained-2/|title=The Venezuela-China relationship, explained: Belt and Road {{!}} Part 2 of 4|date=14 January 2019|website=SupChina|language=en-US|access-date=24 June 2019|archive-url=https://web.archive.org/web/20190624005848/https://supchina.com/2019/01/14/venezuela-china-explained-2/|archive-date=24 June 2019|url-status=live}}</ref>\n\nRolls-Royce aims to sell nuclear reactors for the production of [[synfuel]] for aircraft.<ref>{{Cite web |url=https://www.bloomberg.com/amp/news/articles/2019-12-06/rolls-royce-pitches-nuclear-reactors-as-key-to-clean-jet-fuel |title=Archived copy |website=[[Bloomberg News]] |access-date=19 December 2019 |archive-date=19 December 2019 |archive-url=https://web.archive.org/web/20191219210954/https://www.bloomberg.com/amp/news/articles/2019-12-06/rolls-royce-pitches-nuclear-reactors-as-key-to-clean-jet-fuel |url-status=dead }}</ref>\n\n [[Generation IV reactors]] are a set of theoretical nuclear reactor designs currently being researched. These designs are generally not expected to be available for commercial construction before 2030. Current reactors in operation around the world are generally considered second- or third-generation systems, with the first-generation systems having been retired some time ago. Research into these reactor types was officially started by the Generation IV International Forum (GIF) based on eight technology goals. The primary goals being to improve nuclear safety, improve proliferation resistance, minimize waste and natural resource utilization, and to decrease the cost to build and run such plants.<ref name="UIC1">{{cite web |title=Generation IV Nuclear Reactors |publisher=[[World Nuclear Association]] |url= http://world-nuclear.org/info/inf77.html |access-date=29 January 2010}}</ref>\n* [[Gas-cooled fast reactor]]\n* [[Lead-cooled fast reactor]]\n* [[Molten salt reactor]]\n* [[Sodium-cooled fast reactor]]\n* [[Supercritical water reactor]]\n* [[Very-high-temperature reactor]]\n\n Generation V reactors are designs which are theoretically possible, but which are not being actively considered or researched at present. Though some generation V reactors could potentially be built with current or near term technology, they trigger little interest for reasons of economics, practicality, or safety.\n* Liquid-core reactor. A closed loop [[Nuclear thermal rocket#Liquid core|liquid-core nuclear reactor]], where the fissile material is molten uranium or uranium solution cooled by a working gas pumped in through holes in the base of the containment vessel.\n* [[Gaseous fission reactor|Gas-core reactor]]. A closed loop version of the [[Nuclear lightbulb|nuclear lightbulb rocket]], where the fissile material is gaseous uranium hexafluoride contained in a fused silica vessel. A working gas (such as hydrogen) would flow around this vessel and absorb the UV light produced by the reaction. This reactor design could also function [[Gas core reactor rocket|as a rocket engine]], as featured in Harry Harrison's 1976 science-fiction novel ''Skyfall''. In theory, using UF<sub>6</sub> as a working fuel directly (rather than as a stage to one, as is done now) would mean lower processing costs, and very small reactors. In practice, running a reactor at such high power densities would probably produce unmanageable [[neutron flux]], weakening most [[IFMIF|reactor materials]], and therefore as the flux would be similar to that expected in fusion reactors, it would require similar materials to those selected by the [[IFMIF|International Fusion Materials Irradiation Facility]].\n** Gas core EM reactor. As in the gas core reactor, but with [[photovoltaic]] arrays converting the [[UV light]] directly to electricity.<ref>{{cite web |url=http://isjaee.hydrogen.ru/pdf/AEE04-07_Prelas.pdf |title=International Scientific Journal for Alternative Energy and Ecology, DIRECT CONVERSION OF NUCLEAR ENERGY TO ELECTRICITY, Mark A. Prelas |url-status=dead |archive-url=https://web.archive.org/web/20160304024833/http://isjaee.hydrogen.ru/pdf/AEE04-07_Prelas.pdf |archive-date=4 March 2016  }}</ref> This approach is similar to the experimentally proved [[photoelectric effect]] that would convert the X-rays generated from [[aneutronic fusion]] into electricity, by passing the high energy photons through an array of conducting foils to transfer some of their energy to electrons, the energy of the photon is captured electrostatically, similar to a [[capacitor]]. Since X-rays can go through far greater material thickness than electrons, many hundreds or thousands of layers are needed to absorb the X-rays.<ref>Quimby, D.C., High Thermal Efficiency X-ray energy conversion scheme for advanced fusion reactors, ASTM Special technical Publication, v.2, 1977, pp. 1161\u20131165</ref>\n* [[Fission fragment reactor]]. A fission fragment reactor is a nuclear reactor that generates electricity by decelerating an ion beam of fission byproducts instead of using nuclear reactions to generate heat. By doing so, it bypasses the [[Carnot cycle]] and can achieve efficiencies of up to 90% instead of 40\u201345% attainable by efficient turbine-driven thermal reactors. The fission fragment ion beam would be passed through a [[magnetohydrodynamic generator]] to produce electricity.\n* [[Hybrid nuclear fusion]]. Would use the neutrons emitted by fusion to fission a [[breeder reactor|blanket]] of [[fertile material]], like [[Uranium-238|U-238]] or [[thorium|Th-232]] and [[Nuclear transmutation|transmute]] other reactor's [[spent nuclear fuel]]/nuclear waste into relatively more benign isotopes.\n\n {{Main|Fusion power}}\nControlled [[nuclear fusion]] could in principle be used in [[fusion power]] plants to produce power without the complexities of handling [[actinides]], but significant scientific and technical obstacles remain. Several fusion reactors have been built, but reactors have never been able to release more energy than the amount of energy used in the process. Despite research having started in the 1950s, no commercial fusion reactor is expected before 2050. The [[ITER]] project is currently leading the effort to harness fusion power."}},
{"article_title": "Nuclear power", "pageid": "22153", "revid": "1062411450", "timestamp": "2021-12-28T08:41:47Z", "history_paths": [["Nuclear power --- Introduction ---", "History"]], "categories": ["nuclear power", "energy conversion", "nuclear power stations", "nuclear technology", "power station technology", "articles containing video clips", "global issues"], "heading_tree": {"Nuclear power --- Introduction ---": {"History": {"Origins": {}, "First power generation": {}, "Early accidents": {}, "Expansion and first opposition": {}, "Chernobyl and renaissance": {}, "Fukushima and current prospects": {}}, "Nuclear power plants": {}, "Life cycle of nuclear fuel": {"Uranium resources": {}, "Nuclear waste": {"High-level waste": {}, "Low-level waste": {}, "Waste relative to other types": {}, "Waste disposal": {}}, "Reprocessing": {}, "Breeding": {}}, "Nuclear decommissioning": {}, "Installed capacity and electricity production": {}, "Economics": {}, "Use in space": {}, "Safety": {}, "Accidents and attacks": {"Accidents": {}, "Attacks and sabotage": {}}, "Nuclear proliferation": {}, "Environmental impact{{anchor|Environmental_issues}}": {"Carbon emissions": {}, "Radiation": {}}, "Debate on nuclear power": {"Comparison with renewable energy": {"Speed of transition and investment needed": {}, "Land use": {}}}, "Research": {"Advanced fission reactor designs": {}, "Hybrid nuclear fusion-fission": {}, "Nuclear fusion": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Nuclear power --- Introduction ---|History": "{{main|History of nuclear power}}\n\n [[File:First four nuclear lit bulbs.jpeg|thumb|The first light bulbs ever lit by electricity generated by nuclear power at [[EBR-1]] at [[Argonne National Laboratory]]-West, December 20, 1951.<ref>{{cite web |title=Reactors: Modern-Day Alchemy - Argonne's Nuclear Science and Technology Legacy |url=https://www.ne.anl.gov/About/modern-day-alchemy/ |website=www.ne.anl.gov |access-date=24 March 2021}}</ref>]]\nThe discovery of nuclear fission occurred in 1938 following over four decades of work on the science of [[radioactivity]] and the elaboration of new [[nuclear physics]] that described the components of [[atom]]s.\nSoon after the discovery of the fission process, it was realized that a fissioning nucleus can induce further nucleus fissions, thus inducing a self-sustaining chain reaction.<ref name="Inside the Atomic Patent Office">{{cite journal | doi = 10.2968/064002008 | volume=64 | issue=2 | title=Inside the atomic patent office | year=2008 | journal=Bulletin of the Atomic Scientists | pages=26\u201331 | last1 = Wellerstein | first1 = Alex| bibcode=2008BuAtS..64b..26W }}</ref>\nOnce this was experimentally confirmed in 1939, scientists in many countries petitioned their governments for support of nuclear fission research, just on the cusp of [[World War II]], for the development of a [[nuclear weapon]].<ref>{{cite web|url=http://www.atomicarchive.com/History/mp/introduction.shtml |title=The Einstein Letter |publisher=Atomicarchive.com |access-date=2013-06-22}}</ref>\n\nIn the United States, these research efforts led to the creation of the first man-made nuclear reactor, the [[Chicago Pile-1]], which achieved [[Criticality (status)|criticality]] on December 2, 1942. The reactor's development was part of the [[Manhattan Project]], the [[Allies of World War II|Allied]] effort to create [[atomic bombs]] during World War II. It led to the building of larger single-purpose [[production reactor]]s for the production of [[weapons-grade plutonium]] for use in the first nuclear weapons. The United States tested the first nuclear weapon in July 1945, the [[Trinity test]], with the [[atomic bombings of Hiroshima and Nagasaki]] taking place one month later.\n\n[[File:Nautiluscore.jpg|thumb| The launching ceremony of the {{USS|Nautilus|SSN-571|6}} January 1954. In 1958 it would become the first vessel to reach the [[North Pole]].<ref>{{cite web |title=Nautilus (SSN-571) |url=https://www.history.navy.mil/browse-by-topic/ships/uss-nautilus.html |publisher=US Naval History and Heritage Command (US Navy)}}</ref>]]\n[[File:HD.15.019 (11823864155).jpg|thumb|The [[Calder Hall nuclear power station]] in the United Kingdom, the world's first commercial nuclear power station.]]\nDespite the military nature of the first nuclear devices, the 1940s and 1950s were characterized by strong optimism for the potential of nuclear power to provide cheap and endless energy.<ref>{{cite book |last1=Wendt |first1=Gerald |last2=Geddes |first2=Donald Porter |title=The Atomic Age Opens |date=1945 |publisher=Pocket Books |location=New York |url=http://alsos.wlu.edu/information.aspx?id=279}}</ref> \nElectricity was generated for the first time by a nuclear reactor on December 20, 1951, at the [[EBR-I]] experimental station near [[Arco, Idaho]], which initially produced about 100 [[kW]].<ref>{{cite web |url=http://www.ne.anl.gov/About/reactors/frt.shtml |title=Reactors Designed by Argonne National Laboratory: Fast Reactor Technology |publisher=U.S. Department of Energy, Argonne National Laboratory |year=2012 |access-date=2012-07-25}}</ref><ref>{{cite magazine| url=https://books.google.com/books?id=yNwDAAAAMBAJ&q=1954+Popular+Mechanics+January&pg=PA105 |title=Reactor Makes Electricity |magazine=Popular Mechanics |date= March 1952| page= 105|publisher=Hearst Magazines }}</ref>\nIn 1953, American President [[Dwight Eisenhower]] gave his "[[Atoms for Peace]]" speech at the [[United Nations]], emphasizing the need to develop "peaceful" uses of nuclear power quickly. This was followed by the [[Atomic Energy Act of 1954]] which allowed rapid declassification of U.S. reactor technology and encouraged development by the private sector.\n\n The first organization to develop practical nuclear power was the [[United States Navy|U.S. Navy]], with the [[S1W reactor]] for the purpose of propelling [[submarine]]s and [[aircraft carrier]]s. The first nuclear-powered submarine, {{USS|Nautilus|SSN-571|6}}, was put to sea in January 1954.<ref name="iaeapdf" /><ref>{{cite web |url=http://www.ne.anl.gov/About/reactors/lwr3.shtml#fragment-2 |title=STR (Submarine Thermal Reactor) in "Reactors Designed by Argonne National Laboratory: Light Water Reactor Technology Development" |publisher=U.S. Department of Energy, Argonne National Laboratory |year=2012 |access-date=2012-07-25}}</ref> \nThe [[S1W reactor]] was a [[Pressurized Water Reactor]]. This design was chosen because it was simpler, more compact, and easier to operate compared to alternative designs, thus more suitable to be used in submarines. This decision would result in the PWR being the reactor of choice also for power generation, thus having a lasting impact on the civilian electricity market in the years to come.<ref>{{cite book|last=Rockwell|first=Theodore|title=The Rickover Effect|publisher=Naval Institute Press|year=1992|pages=162|isbn=978-1-55750-702-0}}</ref>\n\nOn June 27, 1954, the [[Obninsk Nuclear Power Plant]] in the [[USSR]] became the world's first nuclear power plant to generate electricity for a [[power grid]], producing around 5 megawatts of electric power.<ref name="IAEANews">{{cite web |url= http://www.iaea.org/NewsCenter/News/2004/obninsk.html |title=From Obninsk Beyond: Nuclear Power Conference Looks to Future |website=[[International Atomic Energy Agency]] | access-date = 2006-06-27|date=2004-06-23 }}</ref> \nThe world's first commercial nuclear power station, [[Calder Hall nuclear power station|Calder Hall]] at Windscale, England was connected to the national power grid on 27 August 1956. In common with a number of other [[generation I reactor]]s, the plant had the dual purpose of producing [[electricity]] and [[plutonium-239]], the latter for the nascent [[Nuclear weapons and the United Kingdom|nuclear weapons program in Britain]].<ref>{{cite book |last1=Hill |first1=C. N. |title=An atomic empire : a technical history of the rise and fall of the British atomic energy programme |date=2013 |publisher=Imperial College Press |location=London |isbn=9781908977434}}</ref>\n\n The first major nuclear accidents were the [[Kyshtym disaster]] in the Soviet Union and the [[Windscale fire]] in the United Kingdom, both in 1957.  The first major accident at a nuclear reactor in the USA occurred in 1961 at the [[SL-1]], a [[U.S. Army]] experimental nuclear power reactor at the [[Idaho National Laboratory]]. An uncontrolled chain reaction resulted in a [[steam explosion]] which killed the three crew members and caused a [[nuclear meltdown|meltdown]].<ref name=ido19313>''[http://www.id.doe.gov/foia/PDF/IDO-19313.pdf IDO-19313: Additional Analysis of the SL-1 Excursion] {{webarchive|url=https://web.archive.org/web/20110927065809/http://www.id.doe.gov/foia/PDF/IDO-19313.pdf |date=2011-09-27 }} Final Report of Progress July through October 1962'', November 21, 1962, Flight Propulsion Laboratory Department, General Electric Company, Idaho Falls, Idaho, U.S. Atomic Energy Commission, Division of Technical Information.</ref><ref>{{cite book |last=McKeown |first=William |title=Idaho Falls: The Untold Story of America's First Nuclear Accident |isbn=978-1-55022-562-4 |year=2003 |publisher=ECW Press |location=Toronto}}</ref> \nAnother serious accident happened in 1968, when one of the two [[liquid-metal-cooled reactor]]s on board the {{ship|Soviet submarine|K-27}} underwent a [[fuel element failure]], with the emission of gaseous [[fission product]]s into the surrounding air, resulting in 9 crew fatalities and 83 injuries.<ref name=johnston2007>{{cite web |url=http://www.johnstonsarchive.net/nuclear/radevents/radevents1.html |title=Deadliest radiation accidents and other events causing radiation casualties |author=Johnston, Robert |date=2007-09-23 |publisher=Database of Radiological Incidents and Related Events }}</ref>\n\n The total global installed nuclear capacity initially rose relatively quickly, rising from less than 1 [[gigawatt]] (GW) in 1960 to 100 GW in the late 1970s.<ref name="iaeapdf">{{cite web |url= http://www.iaea.org/About/Policy/GC/GC48/Documents/gc48inf-4_ftn3.pdf |title=50 Years of Nuclear Energy |access-date=2006-11-09 |publisher=International Atomic Energy Agency }}</ref>\nDuring the 1970s and 1980s rising economic costs (related to extended construction times largely due to regulatory changes and pressure-group litigation)<ref name="Bernard L. Cohen 1990">{{cite book |author=Bernard L. Cohen |date=1990 |title=The Nuclear Energy Option: An Alternative for the 90s |url=https://archive.org/details/nuclearenergyopt0000cohe |location=New York |publisher=Plenum Press |isbn=978-0-306-43567-6 |url-access=registration }}</ref> and falling fossil fuel prices made nuclear power plants then under construction less attractive. In the 1980s in the U.S. and 1990s in Europe, the flat electric grid growth and [[electricity liberalization]] also made the addition of large new [[baseload]] energy generators economically unattractive.\n\nThe [[1973 oil crisis]] had a significant effect on countries, such as [[France]] and [[Japan]], which had relied more heavily on oil for electric generation to invest in nuclear power.<ref>{{cite web| author=Sharon Beder| url=http://www.herinst.org/sbeder/privatisation/japan.html |title=The Japanese Situation, English version of conclusion of Sharon Beder, "Power Play: The Fight to Control the World's Electricity"|publisher= Soshisha, Japan|date= 2006}}</ref>\nFrance would construct 25 nuclear power plants over the next 15 years,<ref name="palfreman">{{Cite news| last = Palfreman| first = Jon| title = Why the French Like Nuclear Energy| work = [[Frontline (U.S. TV series)|Frontline]]| publisher = [[Public Broadcasting Service]]| access-date = 25 August 2007| year = 1997| url = https://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/french.html}}</ref><ref name="de preneuf">{{cite web| last = Rene de Preneuf| title = Nuclear Power in France \u2013 Why does it Work? | access-date = 25 August 2007| url = http://www.npcil.nic.in/nupower_vol13_2/npfr_.htm |archive-url = https://web.archive.org/web/20070813233335/http://www.npcil.nic.in/nupower_vol13_2/npfr_.htm <!-- Bot retrieved archive --> |archive-date = 13 August 2007}}</ref> and as of 2019, 71% of French electricity was generated by nuclear power, the highest percentage by any nation in the world.<ref name=":0" />\n\nSome local opposition to nuclear power emerged in the United States in the early 1960s.<ref name=well>{{cite journal | author = Garb Paula | title = Review of Critical Masses : Opposition to Nuclear Power in California, 1958-1978 | url = http://jpe.library.arizona.edu/volume_6/wellockvol6.htm | journal = Journal of Political Ecology | volume = 6 | year = 1999 }}</ref> In the late 1960s some members of the scientific community began to express pointed concerns.<ref name=wolfgang /> These [[anti-nuclear]] concerns related to [[nuclear accidents]], [[nuclear proliferation]], [[nuclear terrorism]] and [[High-level radioactive waste management|radioactive waste disposal]].<ref name=bm>{{cite journal| author=[[Brian Martin (social scientist)|Brian Martin]]| url= http://www.bmartin.cc/pubs/07sa.html | title=Opposing nuclear power: past and present| journal= Social Alternatives| volume= 26| number=2| date=2007|pages= 43\u201347}}</ref> \nIn the early 1970s, there were large protests about a proposed nuclear power plant in [[Wyhl]], Germany. The project was cancelled in 1975. The anti-nuclear success at Wyhl inspired opposition to nuclear power in other parts of [[Europe]] and [[North America]].<ref name=pub>{{cite book |author1=Stephen Mills |author2=Roger Williams |title=Public acceptance of new technologies : an international review |date=1986 |publisher=Croom Helm |location=London |isbn=9780709943198 |url=https://books.google.com/books?id=SeMNAAAAQAAJ&q=%22public+acceptance+of+new+technologies%22 |pages=375\u2013376}}</ref><ref name=got>Robert Gottlieb (2005). [https://books.google.com/books?id=lR0n6oqMNPkC&dq=transofrmation+of+the+american+environmental+gottlieb+revised&pg=PP1#PPA237,M1 Forcing the Spring: The Transformation of the American Environmental Movement], Revised Edition, Island Press, p. 237.</ref>\n\nBy the mid-1970s [[anti-nuclear]] activism gained a wider appeal and influence, and nuclear power began to become an issue of major public protest.<ref name=jimfalk>{{cite book |last=Falk |first=Jim |date=1982|title=Global Fission: The Battle Over Nuclear Power |url=https://archive.org/details/globalfissionbat00falk |url-access=registration |location = Melbourne |publisher=Oxford University Press |pages=[https://archive.org/details/globalfissionbat00falk/page/95 95\u201396] |isbn=978-0-19-554315-5}}</ref><ref name=eleven>Walker, J. Samuel (2004). ''[https://books.google.com/books?id=tf0AfoynG-EC&dq=Three+Mile+Island:+A+Nuclear+Crisis+in+Historical+Perspective&printsec=frontcover#v=onepage&q=&f=false Three Mile Island: A Nuclear Crisis in Historical Perspective]'' (Berkeley: University of California Press), pp. 10\u201311.</ref> \nIn some countries, the [[Nuclear power debate|nuclear power conflict]] "reached an intensity unprecedented in the history of technology controversies".<ref name="marcuse.org">{{cite journal |author=Herbert P. Kitschelt |date=1986 |title=Political Opportunity and Political Protest: Anti-Nuclear Movements in Four Democracies |url=http://www.marcuse.org/harold/hmimages/seabrook/861KitscheltAntiNuclear4Democracies.pdf |journal=British Journal of Political Science |volume=16 |issue=1 |page=57 |doi=10.1017/s000712340000380x}}</ref><ref name=kits>{{cite journal |author=Herbert P. Kitschelt |date=1986 |title=Political Opportunity and Political Protest: Anti-Nuclear Movements in Four Democracies |url=http://www.marcuse.org/harold/hmimages/seabrook/861KitscheltAntiNuclear4Democracies.pdf |journal=British Journal of Political Science |volume=16 |issue=1 |page=71|doi=10.1017/s000712340000380x}}</ref> The increased public hostility to nuclear power led to a longer license procurement process, regulations and increased requirements for safety equipment, which made new construction much more expensive.<ref name="phyast.pitt.edu">{{cite web |title=Costs of Nuclear Power Plants \u2013 What Went Wrong? |url=http://www.phyast.pitt.edu/~blc/book/chapter9.html |website=www.phyast.pitt.edu}}</ref><ref>{{cite news |url=https://www.washingtonexaminer.com/nuclear-energy-may-soon-be-free-from-its-tangled-regulatory-web | author1=Vance Ginn |author2= Elliott Raia|date= August 18, 2017 |title=nuclear energy may soon be free from its tangled regulatory web |work=Washington Examiner}}</ref>\nIn the United States, over [[List of cancelled nuclear reactors in the United States|120 LWR reactor proposals were ultimately cancelled]]<ref>{{cite web| url=https://fas.org/sgp/crs/misc/RL33442.pdf | title=Nuclear Power: Outlook for New U.S. Reactors | page= 3}}</ref> and the construction of new reactors ground to a halt.<ref name="ReferenceA">{{cite journal |date=1985-02-11 |title=Nuclear Follies |journal=Forbes Magazine|last=Cook|first=James}}</ref>\nThe 1979 [[Three Mile Island accident|accident at Three Mile Island]] with no fatalities, played a major part in the reduction in the number of new plant constructions in many countries.<ref name=wolfgang>{{cite book|editor1-first=Wolfgang |editor1-last=R\u00fcdig|title=Anti-nuclear Movements: A World Survey of Opposition to Nuclear Energy|url=https://books.google.com/books?id=ZXwfAQAAIAAJ|year=1990|publisher=Longman Current Affairs|location=Detroit, MI|isbn=978-0-8103-9000-3|page=1}}</ref>\n\n [[File:\u0426\u0435\u043d\u0442\u0440 \u0433\u043e\u0440\u043e\u0434\u0430 \u041f\u0440\u0438\u043f\u044f\u0442\u044c \u043d\u0430 \u0444\u043e\u043d\u0435 4 \u044d\u043d\u0435\u0440\u0433\u043e\u0431\u043b\u043e\u043a\u0430\u0430 \u0427\u0410\u042d\u0421.jpg|thumb|The town of [[Pripyat (city)|Pripyat]] abandoned since 1986, with the Chernobyl plant and the [[Chernobyl New Safe Confinement]] arch in the distance.]]\n[[File:OL3.jpg|thumb|[[Olkiluoto 3]] under construction in 2009. It was the first [[EPR (nuclear reactor)|EPR]], a modernized PWR design, to start construction. ]]\nDuring the 1980s one new nuclear reactor started up every 17 days on average.<ref>{{cite book |last1=Thorpe, M.S. |first1=Gary S. |title=AP Environmental Science, 6th ed. |date=2015 |publisher=Barrons Educational Series |isbn=978-1-4380-6728-5}} {{ISBN|1-4380-6728-3}}</ref> By the end of the decade, global installed nuclear capacity reached 300 GW. Since the late 1980s, new capacity additions slowed down significantly, with the installed nuclear capacity reaching 366 GW in 2005.\n\nThe 1986 [[Chernobyl disaster]] in the [[USSR]], involving an [[RBMK]] reactor, altered the development of nuclear power and led to a greater focus on meeting international safety and regulatory standards.<ref>{{cite web |url= https://www.iaea.org/newscenter/focus/chernobyl|title=Chernobyl Nuclear Accident|date=14 May 2014|website=www.iaea.org | publisher=IAEA}}</ref> \nIt is considered the worst nuclear disaster in history both in total casualties, with 56 direct deaths, and financially, with the cleanup and the cost estimated at 18 billion [[Soviet ruble]]s (US$68 billion in 2019, adjusted for inflation).<ref name="OECD02-Ch2">{{cite web|url=https://www.oecd-nea.org/rp/reports/2003/nea3508-chernobyl.pdf|title=Chernobyl: Assessment of Radiological and Health Impact, 2002 update; Chapter II \u2013 The release, dispersion and deposition of radionuclides|year=2002|publisher=OECD-NEA|access-date=3 June 2015|archive-url=https://web.archive.org/web/20150622010856/https://www.oecd-nea.org/rp/reports/2003/nea3508-chernobyl.pdf|archive-date=22 June 2015|url-status=live}}</ref><ref name="GorbachevBoC">{{cite AV media |people=Johnson, Thomas (author/director) |date=2006 |title=The battle of Chernobyl |url=https://www.andanafilms.com/catalogueFiche.php?idFiche=255&rub=Toutes%20les%20fiches%20films |publisher=Play Film / Discovery Channel}} (see 1996 interview with Mikhail Gorbachev)</ref> The international organization to promote safety awareness and the professional development of operators in nuclear facilities, the [[World Association of Nuclear Operators]] (WANO), was created as a direct outcome of the 1986 Chernobyl accident.\nThe Chernobyl disaster played a major part in the reduction in the number of new plant constructions in the following years.<ref name=wolfgang/> Influenced by these events, Italy voted against nuclear power in a 1987 referendum, becoming the first country to completely phase out nuclear power in 1990.\n\nIn the early 2000s, nuclear energy was expecting a [[nuclear renaissance]], an increase in the construction of new reactors, due to concerns about [[carbon dioxide emissions]].<ref name=":1" /> \nDuring this period, newer [[generation III reactor]]s, such as the [[EPR (nuclear reactor)|EPR]] began construction, although encountering problems and delays, and going significantly over budget.<ref>{{cite news |title=Areva's Finland reactor to start in 2019 after another delay |url=https://www.reuters.com/article/us-finland-nuclear-olkiluoto/arevas-finland-reactor-to-start-in-2019-after-another-delay-idUSKBN1CE1ND |access-date=3 August 2019 |work=Reuters |date=9 October 2017 |language=en}}</ref>\n{{clear}}\n<gallery mode="packed" heights=100px style="text-align:left">\nAnnual world electricity net generation.svg|Net [[electrical generation]] by source and growth from 1980. In terms of energy generated between 1980 and 2010, the contribution from fission grew the fastest.\nElectricity in France.svg|[[Electricity sector in France|Electricity production in France]], showing the shift to nuclear power. {{legend|#D55E00|thermofossil}}{{legend|#0072B2|hydroelectric}}{{legend|#F0E442|nuclear}}{{legend|#009E73|Other renewables}}\nNuclear power history.svg|The rate of new reactor constructions essentially halted in the late 1980s. Increased [[capacity factor]] in existing reactors was primarily responsible for the continuing increase in electrical energy produced during this period.\nTop 5 Nuclear Energy Producing Countries.png|Electricity generation trends in the top five fission-energy producing countries (US EIA data)\n</gallery>\n\n {{Image frame\n |width = 520\n |align=right\n |pos=bottom\n |content={{Graph:Chart\n | width = 180\n | height = 150\n | type=area \n | interpolate=step-before\n | y= 2263.79 , 2298.27 , 2378.93 , 2443.85 , 2511.09 , 2553.18 , 2504.78 , 2616.24 , 2626.34 , 2660.85 , 2608.18 , 2597.81 , 2558.06 , 2629.82 , 2517.98 , 2346.19 , 2358.86 , 2410.37 , 2441.33 , 2477.30 , 2502.82 , 2562.76 , 2586.16\n | xAxisTitle=Year\n | xAxisAngle = -45\n | xType=date\n | yType=number\n | yAxisTitle=Generation (TWh)\n | x = 1997 ,1998 ,1999 , 2000 ,2001 ,2002 ,2003 ,2004 , 2005 ,2006 ,2007 ,2008 ,2009 , 2010 ,2011 ,2012 ,2013 ,2014 , 2015 , 2016, 2017, 2018, 2019\n}}{{Graph:Chart\n | width = 180\n | height = 150\n | type=area \n | interpolate=step-before\n | y = 441 , 438 , 434 , 438 , 438 , 444 , 443 , 443 , 443 , 443 , 439 , 439 , 440 , 442 , 448 , 440 , 441 , 439 , 448 , 451 , 451 , 457 , 456\n | xAxisTitle=Year\n | xAxisAngle = -45\n | xType=date\n | yType=number\n | yAxisTitle=Number of reactors\n | x = 1997 ,1998 ,1999 , 2000 ,2001 ,2002 ,2003 ,2004 , 2005 ,2006 ,2007 ,2008 ,2009 , 2010 ,2011 ,2012 ,2013 ,2014 , 2015 , 2016, 2017, 2018, 2019\n}}\n|caption = Nuclear power generation (TWh) and operational nuclear reactors since 1997<ref name="pris-supplied" />\n}}\nPlans for a nuclear renaissance were ended by another nuclear accident.<ref name=carbonbrief_2016>{{cite news |title=Analysis: The legacy of the Fukushima nuclear disaster |url=https://www.carbonbrief.org/analysis-the-legacy-of-the-fukushima-nuclear-disaster |access-date=24 March 2021 |work=Carbon Brief |date=10 March 2016 |language=en}}</ref><ref name=":1">{{cite news|url=https://www.reuters.com/article/us-japan-quake-nuclear-analysis-idUSTRE72C41W20110314 |title= Analysis: Nuclear renaissance could fizzle after Japan quake |work= Reuters|date=2011-03-14| access-date= 2011-03-14}}</ref>\nThe 2011 [[Fukushima Daiichi nuclear accident]] was caused by a large tsunami triggered by the [[2011 T\u014dhoku earthquake and tsunami|T\u014dhoku earthquake]], one of the largest earthquakes ever recorded. The [[Fukushima Daiichi Nuclear Power Plant]] suffered three core meltdowns due to failure of the emergency cooling system for lack of electricity supply. This resulted in the most serious nuclear accident since the Chernobyl disaster. The accident prompted a re-examination of [[nuclear safety]] and [[nuclear energy policy]] in many countries.<ref name=sciamer2011>{{cite journal |author1=Sylvia Westall |author2=Fredrik Dahl |name-list-style=amp |date=2011-06-24 |title=IAEA Head Sees Wide Support for Stricter Nuclear Plant Safety |url=http://www.scientificamerican.com/article.cfm?id=iaea-head-sees-wide-support |archive-url=https://archive.today/20110625042535/http://www.scientificamerican.com/article.cfm?id=iaea-head-sees-wide-support |url-status=dead |archive-date=2011-06-25 |journal=Scientific American }}</ref>\nGermany approved plans to close all its reactors by 2022, and many other countries reviewed their nuclear power programs.<ref>{{cite news |author=Jo Chandler |date=2011-03-19 |title=Is this the end of the nuclear revival? |url=https://www.smh.com.au/world/is-this-the-end-of-the-nuclear-revival-20110318-1c0i9.html |newspaper=The Sydney Morning Herald|author-link=Jo Chandler }}</ref><ref>{{cite news |author=Aubrey Belford |date=2011-03-17 |title=Indonesia to Continue Plans for Nuclear Power |url=https://www.nytimes.com/2011/03/18/business/global/18atomic.html?partner=rss&emc=rss |newspaper=The New York Times}}</ref><ref name="piersmorgan.blogs.cnn.com">{{cite news|url=http://piersmorgan.blogs.cnn.com/2011/03/17/israel-prime-minister-netanyahu-japan-situation-has-caused-me-to-reconsider-nuclear-power/ |title=Israel Prime Minister Netanyahu: Japan situation has "caused me to reconsider" nuclear power|author= Piers Morgan |work=CNN|date=2011-03-17| access-date= 2011-03-17}}</ref><ref name="news.xinhuanet.com">{{cite news|url=http://news.xinhuanet.com/english2010/world/2011-03/18/c_13784578.htm |title=Israeli PM cancels plan to build nuclear plant|work= xinhuanet.com|date=2011-03-18| access-date= 2011-03-17}}</ref>\nFollowing the disaster, Japan shut down all of its nuclear power reactors, some of them permanently, and in 2015 began a gradual process to restart the remaining 40 reactors, following safety checks and based on revised criteria for operations and public approval.<ref>{{cite web |url=http://www.kyuden.co.jp/en_information_150811.html |title=Startup of Sendai Nuclear Power Unit No.1 |date=2015-08-11 |website=Kyushu Electric Power Company Inc. |access-date=2015-08-12 |archive-url=https://web.archive.org/web/20170525170529/http://www.kyuden.co.jp/en_information_150811.html |archive-date=2017-05-25 |url-status=dead }}</ref>\n\nBy 2015, the IAEA's outlook for nuclear energy had become more promising, recognizing the importance of low-carbon generation for mitigating climate change.<ref>{{cite web|url=http://www.iea.org/newsroomandevents/news/2015/january/taking-a-fresh-look-at-the-future-of-nuclear-power.html|title=January: Taking a fresh look at the future of nuclear power|website=www.iea.org}}</ref>\n{{As of|2015}}, the global trend was for new nuclear power stations coming online to be balanced by the number of old plants being retired.<ref>{{cite web|publisher=[[World Nuclear Association]] |url=http://www.world-nuclear.org/info/current-and-future-generation/plans-for-new-reactors-worldwide/ |title=Plans for New Reactors Worldwide |date=October 2015}}</ref> \nIn 2016, the [[U.S. Energy Information Administration]] projected for its "base case" that world nuclear power generation would increase from 2,344 [[terawatt hour]]s (TWh) in 2012 to 4,500 TWh in 2040. Most of the predicted increase was expected to be in Asia.<ref>{{cite web| url=http://www.eia.gov/forecasts/aeo/data/browser/#/?id=31-IEO2016&sourcekey=0 | title=International Energy outlook 2016 | publisher= US Energy Information Administration |access-date= 17 August 2016}}</ref> As of 2018, there are over 150 nuclear reactors planned including 50 under construction.<ref>{{Cite web|title=Plans for New Nuclear Reactors Worldwide|url=http://www.world-nuclear.org/information-library/current-and-future-generation/plans-for-new-reactors-worldwide.aspx|access-date=2018-09-29|website=www.world-nuclear.org|publisher=World Nuclear Association}}</ref> In January 2019, China had 45 reactors in operation, 13 under construction, and plans to build 43 more, which would make it the world's largest generator of nuclear electricity.<ref name=china19>{{cite magazine|title=Can China become a scientific superpower? - The great experiment|url=https://www.economist.com/science-and-technology/2019/01/12/can-china-become-a-scientific-superpower|magazine=The Economist|date=12 January 2019|access-date=25 January 2019}}</ref> As of 2021, 17 reactors were reported to be under construction. China built significantly fewer reactors than originally planned, its share of electricity from nuclear power was 5% in 2019<ref name="dwfrance">{{cite news |title=A global nuclear phaseout or renaissance? {{!}} DW {{!}} 04.02.2021 |url=https://www.dw.com/en/germany-looking-for-final-repository-for-nuclear-waste-global-outlook/a-56449115 |access-date=25 November 2021 |work=Deutsche Welle (www.dw.com)}}</ref> and observers have cautioned that, along with the risks, the changing economics of energy generation may cause new nuclear energy plants to "no longer make sense in a world that is leaning toward cheaper, more reliable renewable energy".<ref name="cnnchina">{{cite news |last1=Griffiths |first1=James |title=China's gambling on a nuclear future, but is it destined to lose? |url=https://edition.cnn.com/2019/09/13/business/china-nuclear-climate-intl-hnk/index.html |access-date=25 November 2021 |work=CNN}}</ref><ref name="francere">{{cite news |title=Building new nuclear plants in France uneconomical -environment agency |url=https://www.reuters.com/article/france-nuclearpower/building-new-nuclear-plants-in-france-uneconomical-environment-agency-idUSL8N1YF5HC |access-date=25 November 2021 |work=Reuters |date=10 December 2018 |language=en}}</ref>"}},
{"article_title": "Penicillin", "pageid": "23312", "revid": "1061490129", "timestamp": "2021-12-22T01:04:35Z", "history_paths": [["Penicillin --- Introduction ---", "History"]], "categories": ["penicillins", "1928 in biology", "eli lilly and company brands", "gabaa receptor negative allosteric modulators", "hepatotoxins", "microbiology", "penicillium", "pfizer brands", "science and technology during world war ii", "scottish inventions", "secondary metabolites"], "heading_tree": {"Penicillin --- Introduction ---": {"Nomenclature": {"Penicillin units": {}}, "Types": {"Natural penicillins": {}, "Semi-synthetic penicillin": {}, "Antibiotics created from 6-APA": {"Antistaphylococcal antibiotics": {}, "Broad-spectrum antibiotics": {}, "Antipseudomonal antibiotics": {"Carboxypenicillins": {}, "Ureidopenicillins": {}}}, "\u03b2-lactamase inhibitors": {}}, "Medical usage": {"Penicillin G": {}, "Penicillin V": {}, "Bacterial susceptibility": {}}, "Side effects": {}, "Structure": {}, "Pharmacology": {"Entry into bacteria": {}, "Mechanism of action": {}, "Pharmacokinetics": {}}, "Resistance": {}, "History": {"Discovery": {}, "Medical application": {}, "Mass production": {}, "Structure determination and total synthesis": {}, "Developments from penicillin": {}}, "Production": {"Biosynthesis": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Penicillin --- Introduction ---|History": "{{Main|History of penicillin}}\n\n [[File:Alexander Fleming.jpg|thumb|[[Alexander Fleming]], who is credited with discovering penicillin in 1928.]]\n[[File:Sample of penicillin mould presented by Alexander Fleming to Douglas Macleod, 1935 (9672239344).jpg|thumb|Sample of ''[[penicillium]]'' mould presented by Alexander Fleming to Douglas Macleod, 1935]]\n\nStarting in the late 19th century there had been reports of the antibacterial properties of ''Penicillium'' mould, but scientists were unable to discern what process was causing the effect.<ref>{{cite book | vauthors = Dougherty TJ, Pucci MJ | title = Antibiotic Discovery and Development | publisher = Springer Science & Business Media | date = 2011 | pages = 79\u201380 }}</ref> Scottish physician Alexander Fleming at [[St Mary's Hospital, London|St Mary's Hospital]] in London (now part of [[Imperial College]]) was the first to show that ''[[Penicillium rubens]]'' had antibacterial properties.<ref>{{cite book | vauthors = Landau R, Achilladelis B, Scriabine A | title = Pharmaceutical Innovation: Revolutionizing Human Health | publisher = Chemical Heritage Foundation | date = 1999 | page = 162 }}</ref> On 3 September 1928 he observed that fungal contamination of a bacterial culture (''[[Staphylococcus aureus]]'') appeared to kill the bacteria. He confirmed this observation with a new experiment on 28 September 1928.<ref>{{cite book | vauthors = Haven KF |title=Marvels of Science: 50 Fascinating 5-Minute Reads |publisher=Libraries Unlimited |location=Littleton, CO |year=1994 |pages=182 |isbn=978-1-56308-159-0 }}</ref> He published his experiment in 1929, and called the antibacterial substance (the fungal extract) penicillin.<ref name="Fleming1929">{{cite journal |title=On the Antibacterial Action of Cultures of a Penicillium, with Special Reference to their Use in the Isolation of B. influenz\u00e6 | vauthors = Fleming A | journal = British Journal of Experimental Pathology |year=1929 |volume=10|issue=3|pages=226\u2013236|pmc=2048009}}\nReprinted as {{cite journal | vauthors = Fleming A | title = Classics in infectious diseases: on the antibacterial action of cultures of a penicillium, with special reference to their use in the isolation of B. influenzae by Alexander Fleming, Reprinted from the British Journal of Experimental Pathology 10:226-236, 1929 | journal = Reviews of Infectious Diseases | volume = 2 | issue = 1 | pages = 129\u201339 | year = 1980 | pmid = 6994200 | pmc = 2041430 | doi = 10.1093/clinids/2.1.129 }}</ref>\n\nC. J. La Touche identified the fungus as ''Penicillium rubrum'' (later reclassified by [[Charles Thom]] as ''P. notatum'' and ''P. chrysogenum'', but later corrected as ''[[Penicillium rubens|P. rubens]]'').<ref>{{cite journal | vauthors = Houbraken J, Frisvad JC, Samson RA | title = Fleming's penicillin producing strain is not Penicillium chrysogenum but P. rubens | journal = IMA Fungus | volume = 2 | issue = 1 | pages = 87\u201395 | date = June 2011 | pmid = 22679592 | pmc = 3317369 | doi = 10.5598/imafungus.2011.02.01.12 }}</ref> Fleming expressed initial optimism that penicillin would be a useful antiseptic, because of its high potency and minimal toxicity in comparison to other antiseptics of the day, and noted its laboratory value in the isolation of ''Bacillus influenzae'' (now called ''[[Haemophilus influenzae]]'').<ref name="Lax2004">{{cite book| vauthors = Lax E  |url= https://archive.org/details/moldindrfloreysc00eric |title=The Mold in Dr. Florey's Coat: The Story of the Penicillin Miracle |publisher=Holt Paperbacks |year=2004 |isbn=978-0-8050-7778-0 }}</ref><ref name=Krylov1991>{{cite journal | vauthors = Krylov AK | title = [Gastroenterologic aspects of the clinical picture of internal diseases] | journal = Terapevticheskii Arkhiv | volume = 63 | issue = 2 | pages = 139\u201341 | year = 1991 | pmid = 2048009 }}</ref>\n<!--Reprinted in {{cite journal | vauthors = Fleming A | title = On the antibacterial action of cultures of a penicillium, with special reference to their use in the isolation of B. influenzae. 1929 | journal = Bulletin of the World Health Organization | volume = 79 | issue = 8 | pages = 780\u201390 | year = 2001 | pmid = 11545337 | pmc = 2566493 }}   This made absolutely no sense at all. The Russian paper is from 1991, and could not have been reprinted in Fleming's original 1929 paper. The ''Bulletin'' link is to an image PDF of of Fleming's paper. There is another link above to a reprint of Fleming's paper in ''Reviews of Infectious Diseases''-->\n\nFleming did not convince anyone that his discovery was important.<ref name=Lax2004 /> This was largely because penicillin was so difficult to isolate that its development as a drug seemed impossible. It is speculated that had Fleming been more successful at making other scientists interested in his work, penicillin would possibly have been developed years earlier.<ref name=Lax2004 />\n\nThe importance of his work has been recognized by the placement of an [[International Historic Chemical Landmark]] at the Alexander Fleming Laboratory Museum in London on 19 November 1999.<ref name="Landmark">{{cite web |title=Discovery and Development of Penicillin |url=https://www.acs.org/content/acs/en/education/whatischemistry/landmarks/flemingpenicillin.html |publisher = American Chemical Society |work = International Historic Chemical Landmarks |access-date = August 21, 2018 }}</ref>\n\n [[File:Howard Walter Florey 1945.jpg|thumb|[[Howard Florey]] (pictured), Alexander Fleming and [[Ernst Chain]] shared a [[Nobel Prize in Physiology or Medicine]] in 1945 for their work on penicillin.]]\nIn 1930, Cecil George Paine, a [[pathologist]] at the [[Sheffield Royal Infirmary|Royal Infirmary]] in [[Sheffield]], successfully treated [[Neonatal conjunctivitis|ophthalmia neonatorum]], a gonococcal infection in infants, with penicillin (fungal extract) on November 25, 1930.<ref name="Wainwright, M & Swan, HT 1986 42\u201356">{{cite journal | vauthors = Wainwright M, Swan HT | title = C.G. Paine and the earliest surviving clinical records of penicillin therapy | journal = Medical History | volume = 30 | issue = 1 | pages = 42\u201356 | date = January 1986 | pmid = 3511336 | pmc = 1139580 | doi = 10.1017/S0025727300045026 }}</ref><ref>{{cite journal | vauthors = Howie J | title = Penicillin: 1929-40 | journal = British Medical Journal | volume = 293 | issue = 6540 | pages = 158\u20139 | date = July 1986 | pmid = 3089435 | pmc = 1340901 | doi = 10.1136/bmj.293.6540.158 }}</ref><ref>{{cite journal | vauthors = Wainwright M | title = The history of the therapeutic use of crude penicillin | journal = Medical History | volume = 31 | issue = 1 | pages = 41\u201350 | date = January 1987 | pmid = 3543562 | pmc = 1139683 | doi = 10.1017/s0025727300046305 }}</ref>\n\nIn 1940, Australian scientist [[Howard Walter Florey|Howard Florey]] (later Baron Florey) and a team of researchers ([[Ernst Boris Chain|Ernst Chain]], [[Edward Abraham]], [[Arthur Duncan Gardner]], [[Norman Heatley]], [[Margaret Jennings (scientist)|Margaret Jennings]], Jean Orr-Ewing and Arthur Gordon Sanders) at the Sir William Dunn School of Pathology, [[University of Oxford]] made progress in making concentrated penicillin from fungal culture broth that showed both ''in vitro'' and ''[[in vivo]]'' bactericidal action.<ref name=":0" /><ref>{{Cite web|url=https://www.nobelprize.org/nobel_prizes/medicine/laureates/1945/chain-lecture.html|title=Ernst B. Chain \u2013 Nobel Lecture: The Chemical Structure of the Penicillins|website=www.nobelprize.org|access-date=2017-05-10}}</ref> In 1941, they treated a policeman, [[Albert Alexander (police officer)|Albert Alexander]], with a severe face infection; his condition improved, but then supplies of penicillin ran out and he died. Subsequently, several other patients were treated successfully.<ref name="SW" /> In December 1942, survivors of the [[Cocoanut Grove fire]] in Boston were the first burn patients to be successfully treated with penicillin.<ref>{{cite book | vauthors = Levy SB | title = The Antibiotic Paradox: How the Misuse of Antibiotics Destroys Their Curative Powers | publisher = Da Capo Press | year = 2002 | pages = 5\u20137 | isbn = 978-0-7382-0440-6 }}</ref>\n\nThe first successful use of pure penicillin was when Fleming treated Harry Lambert of fatal infection of the nervous system (streptococcal [[meningitis]]) in 1942. By that time the Oxford team could produce only a small amount. Florey willingly gave the only available sample to Fleming. Lambert showed improvement from the very next day of the treatment, and was completely cured within a week.<ref name=":42">{{cite journal | vauthors = Bennett JW, Chung KT | title = Alexander Fleming and the discovery of penicillin | journal = Advances in Applied Microbiology | volume = 49 | pages = 163\u201384 | date = 2001 | pmid = 11757350 | doi = 10.1016/s0065-2164(01)49013-7 | publisher = Elsevier | isbn = 978-0-12-002649-4 }}</ref><ref>{{Cite journal| vauthors = Cairns H, Lewin WS, Duthie ES, Smith H |date=1944|title=Pneumococcal Meningitis Treated with Penicillin |journal=The Lancet|language=en|volume=243|issue=6299|pages=655\u2013659|doi=10.1016/S0140-6736(00)77085-1}}</ref> Fleming published his clinical trial in ''[[The Lancet]]'' in 1943.<ref name="Fleming 1943 434\u2013438"/> Following the medical breakthrough the British [[War Cabinet]] set up the Penicillin Committee on 5 April 1943 that led to projects for [[mass production]].<ref>{{Cite journal| vauthors = Mathews JA |date=2008|title=The Birth of the Biotechnology Era: Penicillin in Australia, 1943\u201380 |journal=Prometheus|volume=26|issue=4|pages=317\u2013333|doi=10.1080/08109020802459306|s2cid=143123783}}</ref><ref>{{Cite book| vauthors = Baldry P |url=https://books.google.com/books?id=rvs8AAAAIAAJ|title=The Battle Against Bacteria: A Fresh Look|date=1976|publisher=CUP Archive|isbn=978-0-521-21268-7|pages=115|language=en}}</ref>\n\n As the medical application was established, the Oxford team found that it was impossible to produce usable amounts in their laboratory.<ref name=SW /> Failing to persuade the British government,  Florey and Heatley travelled to the US in June 1941 with their mould samples in order to interest the US government for large-scale production.<ref name=":10">{{cite journal | vauthors = Boucher HW, Talbot GH, Benjamin DK, Bradley J, Guidos RJ, Jones RN, Murray BE, Bonomo RA, Gilbert D | display-authors = 6 | title = 10 x '20 Progress--development of new drugs active against gram-negative bacilli: an update from the Infectious Diseases Society of America | journal = Clinical Infectious Diseases | volume = 56 | issue = 12 | pages = 1685\u201394 | date = June 2013 | pmc = 5403050 | doi = 10.3201/eid2305.161556 | pmid = 23599308 }}</ref> They approached the [[USDA]] Northern Regional Research Laboratory (NRRL, now the [[National Center for Agricultural Utilization Research]]) at Peoria, Illinois, where facilities for large-scale fermentations were established.<ref name=":12">{{Cite web| vauthors = Carroll A |date=2014-06-02|title=Here is Where: Penicillin Comes to Peoria|url=https://www.historynet.com/here-is-where-penicillin-comes-to-peoria.htm|access-date=2021-01-04|website=HistoryNet|language=en-US}}</ref> Mass culture of the mould and search for better moulds immediately followed.<ref name=":10" />\n\nOn March 14, 1942, the first patient was treated for streptococcal sepsis with US-made penicillin produced by [[Merck & Co.]]<ref name="pmid18626052">{{cite journal | vauthors = Grossman CM | title = The first use of penicillin in the United States | journal = Annals of Internal Medicine | volume = 149 | issue = 2 | pages = 135\u20136 | date = July 2008 | pmid = 18626052 | doi = 10.7326/0003-4819-149-2-200807150-00009 | s2cid = 40197907 }}</ref> Half of the total supply produced at the time was used on that one patient, Anne Miller.<ref>{{cite news|url=http://time.com/4250235/penicillin-1942-history/|title=Penicillin history: what happened to first American patient|work=[[Time (magazine)|Time]]|date=14 March 2016| vauthors = Rothman L |access-date=12 March 2019}}</ref> By June 1942, just enough US penicillin was available to treat ten patients.<ref>{{cite web | vauthors = Mailer JS, Mason B |url=http://www.lib.niu.edu/2001/iht810139.html |title=Penicillin : Medicine's Wartime Wonder Drug and Its Production at Peoria, Illinois | publisher=lib.niu.edu | access-date=February 11, 2008}}</ref> In July 1943, the [[War Production Board]] drew up a plan for the mass distribution of penicillin stocks to Allied troops fighting in Europe.<ref name="JParas" /> The results of fermentation research on [[corn steep liquor]] at the NRRL allowed the United States to produce 2.3 million doses in time for the [[invasion of Normandy]] in the spring of 1944. After a worldwide search in 1943, a mouldy [[cantaloupe]] in a [[Peoria, Illinois]] market was found to contain the best strain of mould for production using the corn steep liquor process.<ref>{{cite web| vauthors = Bellis M |title=The History of Penicillin |url=http://inventors.about.com/od/pstartinventions/a/Penicillin.htm| work=Inventors |publisher=About.com |access-date=October 30, 2007}}</ref> [[Pfizer]] scientist [[Jasper H. Kane]] suggested using a deep-tank fermentation method for producing large quantities of pharmaceutical-grade penicillin.<ref name="Lehrer2006">{{cite book| vauthors = Lehrer S |title=Explorers of the Body: Dramatic Breakthroughs in Medicine from Ancient Times to Modern Science|date=2006|publisher=iUniverse|location=New York|isbn=978-0-595-40731-6|pages=329\u2013330|edition=2nd}}</ref><ref name="Greenwood_2008" />{{rp|109}} Large-scale production resulted from the development of a deep-tank fermentation plant by [[chemical engineer]] [[Margaret Hutchinson Rousseau]].<ref name="Madhavan">{{cite book| vauthors = Madhavan G |title=Think Like an Engineer|date=Aug 20, 2015|publisher=Oneworld Publications|isbn=978-1-78074-637-1|pages=83\u201385, 91\u201393|url=https://books.google.com/books?id=GNAfCgAAQBAJ&pg=PT44|access-date=20 November 2016}}</ref> As a direct result of the war and the War Production Board, by June 1945, over 646 billion units per year were being produced.<ref name="JParas">{{cite book| vauthors = Parascandola J |author-link=John Parascandola |title=The History of antibiotics: a symposium| publisher=American Institute of the History of Pharmacy No. 5 |year=1980 |isbn=978-0-931292-08-8 }}</ref>\n\nG. Raymond Rettew made a significant contribution to the American war effort by his techniques to produce commercial quantities of penicillin, wherein he combined his knowledge of mushroom spawn with the function of the Sharples Cream Separator.<ref>{{cite web|title=G. Raymond Rettew Historical Marker|url=http://explorepahistory.com/hmarker.php?markerId=1-A-2F2|website=ExplorePAhistory.com|access-date=June 27, 2019}}</ref>\nBy 1943, Rettew's lab was producing most of the world's penicillin.  During [[World War II]], penicillin made a major difference in the number of deaths and amputations caused by infected wounds among [[Allies of World War II|Allied]] forces, saving an estimated 12%\u201315% of lives.<ref>{{Cite journal| vauthors = Goyotte D |date=2017 |title=The Surgical Legacy of World War II. Part II: The age of antibiotics|url=https://www.ast.org/ceonline/articles/402/files/assets/common/downloads/publication.pdf|journal=The Surgical Technologist|volume=109|pages=257\u2013264|via=}}</ref> Availability was severely limited, however, by the difficulty of manufacturing large quantities of penicillin and by the rapid [[clearance (medicine)|renal clearance]] of the drug, necessitating frequent dosing. Methods for mass production of penicillin were patented by [[Andrew Jackson Moyer]] in 1945.<ref>{{cite patent | country = US | number = 2442141 | inventor = Moyer AJ | assign1 = US Agriculture | title = Method for Production of Penicillin | gdate = 25 March 1948 }}</ref><ref>{{cite patent | country = US | number = 2443989 | inventor = Moyer AJ | assign1 = US Agriculture | title = Method for Production of Penicillin | gdate = 22 June 1948 }}</ref><ref>{{cite patent | country = US | number = 2476107 | inventor = Moyer AJ | assign1 = US Agriculture | title = Method for Production of Penicillin | gdate = 12 July 1949 }}</ref> Florey had not patented penicillin, having been advised by Sir [[Henry Hallett Dale|Henry Dale]] that doing so would be unethical.<ref name="SW">{{cite web | title = Making Penicillin Possible: Norman Heatley Remembers | access-date = 2007-02-13 | year = 2007 | work = ScienceWatch | publisher = [[Thomson Scientific]]| url=http://www.sciencewatch.com/interviews/norman_heatly.htm | archive-url= https://web.archive.org/web/20070221041204/http://www.sciencewatch.com/interviews/norman_heatly.htm| archive-date=February 21, 2007}}</ref>\n\nPenicillin is actively excreted, and about 80% of a penicillin dose is cleared from the body within three to four hours of administration. Indeed, during the early penicillin era, the drug was so scarce and so highly valued that it became common to collect the urine from patients being treated, so that the penicillin in the urine could be isolated and reused.<ref name=Silverthorn2004>{{cite book | vauthors=Silverthorn DU | title=Human physiology: an integrated approach. | edition=3rd | location=Upper Saddle River (NJ) | publisher=Pearson Education | year=2004 | isbn=978-0-8053-5957-2 | url-access=registration | url=https://archive.org/details/humanphysiology00deeu }}</ref> This was not a satisfactory solution, so researchers looked for a way to slow penicillin excretion. They hoped to find a molecule that could compete with penicillin for the organic acid transporter responsible for excretion, such that the transporter would preferentially excrete the competing molecule and the penicillin would be retained. The [[uricosuric]] agent [[probenecid]] proved to be suitable. When probenecid and penicillin are administered together, probenecid competitively inhibits the excretion of penicillin, increasing penicillin's concentration and prolonging its activity. Eventually, the advent of mass-production techniques and semi-synthetic penicillins resolved the supply issues, so this use of probenecid declined.<ref name=Silverthorn2004 /> Probenecid is still useful, however, for certain infections requiring particularly high concentrations of penicillins.<ref>{{cite journal | vauthors = Luque Paz D, Lakbar I, Tattevin P | title = A review of current treatment strategies for infective endocarditis | journal = Expert Review of Anti-Infective Therapy | volume = 19 | issue = 3 | pages = 297\u2013307 | date = March 2021 | pmid = 32901532 | doi = 10.1080/14787210.2020.1822165 | s2cid = 221572394 }}</ref>\n\nAfter World War II, Australia was the first country to make the drug available for civilian use. In the U.S., penicillin was made available to the general public on March 15, 1945.<ref name="DR">{{cite web | url = http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/flemingpenicillin.html | title = Discovery and development of penicillin | publisher = [[American Chemical Society]]|year=1999}}</ref>\n\nFleming, Florey, and Chain shared the 1945 Nobel Prize in Physiology or Medicine for the development of penicillin.\n\n<gallery widths="200px" heights="200px">\nFile:Penicillin Past, Present and Future- the Development and Production of Penicillin, England, 1943 D16959.jpg|A technician preparing penicillin in 1943\nFile:PenicillinPSAedit.jpg|Penicillin was being mass-produced in 1944.\nFile:Penicillin poster 5.40.tif|World War II poster extolling use of penicillin\nFile:Dorothy Hodgkin Nobel.jpg|[[Dorothy Hodgkin]] determined the chemical structure of penicillin.\n</gallery>\n\n [[File:Molecular model of Penicillin by Dorothy Hodgkin (9663803982).jpg|thumb|Dorothy Hodgkin's model of penicillin's structure.]]\nThe [[chemical structure]] of penicillin was first proposed by [[Edward Abraham]] in 1942<ref name=":0">{{Cite journal| vauthors = Jones DS, Jones JH | date=2014-12-01|title=Sir Edward Penley Abraham CBE. 10 June 1913 \u2013 9 May 1999|url=http://rsbm.royalsocietypublishing.org/content/60/5.1|journal=Biographical Memoirs of Fellows of the Royal Society|volume=60|pages=5\u201322|doi=10.1098/rsbm.2014.0002|issn=0080-4606|doi-access=free}}</ref> and was later confirmed in 1945 using [[X-ray crystallography]] by [[Dorothy Hodgkin|Dorothy Crowfoot Hodgkin]], who was also working at Oxford.<ref>[https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1964/perspectives.html The Nobel Prize in Chemistry 1964, Perspectives]. Retrieved July 14, 2012.</ref> She later in 1964 received the Nobel Prize for Chemistry for this and other structure determinations.\n\nChemist [[John C. Sheehan]] at the [[Massachusetts Institute of Technology]] (MIT) completed the first chemical [[total synthesis|synthesis]] of penicillin in 1957.<ref name=Sheehan1957>{{cite journal| vauthors = Sheehan JC, Henery-Logan KR |title=The Total Synthesis of Penicillin V|journal=Journal of the American Chemical Society|date=March 5, 1957|volume=79|issue=5|pages=1262\u20131263|doi=10.1021/ja01562a063}}</ref><ref name=Sheehan1959>{{cite journal| vauthors = Sheehan JC, Henery-Loganm KR |title=The Total Synthesis of Penicillin V|journal=Journal of the American Chemical Society|date=June 20, 1959|volume=81|issue=12|pages=3089\u20133094|doi=10.1021/ja01521a044}}</ref><ref name=NAPSheehan>{{cite web|title=Biographical Memoirs: John Clark Sheehan|url=http://www.nap.edu/readingroom.php?book=biomems&page=jsheehan.html|publisher=The National Academy Press|access-date=January 28, 2013| vauthors = Corey EJ, Roberts JD |author-link1=Elias James Corey|author-link2=John D. Roberts }}</ref> Sheehan had started his studies into penicillin synthesis in 1948, and during these investigations developed new methods for the synthesis of [[peptides]], as well as new [[protecting group]]s\u2014groups that mask the reactivity of certain functional groups.<ref name=NAPSheehan /><ref name=ArtTotalSyn>{{cite journal | vauthors = Nicolaou KC, Vourloumis D, Winssinger N, Baran PS | title = The Art and Science of Total Synthesis at the Dawn of the Twenty-First Century | journal = Angewandte Chemie | volume = 39 | issue = 1 | pages = 44\u2013122 | date = January 2000 | pmid = 10649349 | doi = 10.1002/(SICI)1521-3773(20000103)39:1<44::AID-ANIE44>3.0.CO;2-L | author-link4 = Phil S. Baran | author-link1 = K. C. Nicolaou }}</ref> Although the initial synthesis developed by Sheehan was not appropriate for mass production of penicillins, one of the intermediate compounds in Sheehan's synthesis was 6-aminopenicillanic acid (6-APA), the nucleus of penicillin.<ref name="Sheehan1957" /><ref name="Sheehan1959" /><ref name=NAPSheehan /><ref name=MITSheehan>{{cite news|title=Professor John C. Sheehan Dies at 76|url=http://web.mit.edu/newsoffice/1992/sheehan-0401.html|access-date=January 28, 2013|newspaper=MIT News|date=April 1, 1992}}</ref>\n\n6-APA was discovered by researchers at the Beecham Research Laboratories (later the [[Beecham Group]]) in Surrey in 1957 (published in 1959).<ref>{{cite journal | vauthors = Batchelor FR, Doyle FP, Nayler JH, Rolinson GN | title = Synthesis of penicillin: 6-aminopenicillanic acid in penicillin fermentations | journal = Nature | volume = 183 | issue = 4656 | pages = 257\u20138 | date = January 1959 | pmid = 13622762 | doi = 10.1038/183257b0 | s2cid = 4268993 | bibcode = 1959Natur.183..257B }}</ref> Attaching different groups to the 6-APA 'nucleus' of penicillin allowed the creation of new forms of penicillins which are more versatile and better in activity.<ref>{{cite journal | vauthors = Rolinson GN, Geddes AM | title = The 50th anniversary of the discovery of 6-aminopenicillanic acid (6-APA) | journal = International Journal of Antimicrobial Agents | volume = 29 | issue = 1 | pages = 3\u20138 | date = January 2007 | pmid = 17137753 | doi = 10.1016/j.ijantimicag.2006.09.003 }}</ref>\n\n The narrow range of treatable diseases or "spectrum of activity" of the penicillins, along with the poor activity of the orally active phenoxymethylpenicillin, led to the search for derivatives of penicillin that could treat a wider range of infections. The isolation of 6-APA, the nucleus of penicillin, allowed for the preparation of semisynthetic penicillins, with various improvements over benzylpenicillin (bioavailability, spectrum, stability, tolerance).\n\nThe first major development was ampicillin in 1961. It offered a broader spectrum of activity than either of the original penicillins. Further development yielded \u03b2-lactamase-resistant penicillins, including flucloxacillin, dicloxacillin, and methicillin. These were significant for their activity against \u03b2-lactamase-producing bacterial species, but were ineffective against the [[methicillin-resistant Staphylococcus aureus|methicillin-resistant ''Staphylococcus aureus'']] (MRSA) strains that subsequently emerged.<ref>{{cite journal | vauthors = Colley EW, Mcnicol MW, Bracken PM | title = Methicillin-Resistant Staphylococci in a General Hospital | journal = Lancet | volume = 1 | issue = 7385 | pages = 595\u20137 | date = March 1965 | pmid = 14250094 | doi = 10.1016/S0140-6736(65)91165-7 }}</ref>\n\nAnother development of the line of true penicillins was the antipseudomonal penicillins, such as carbenicillin, ticarcillin, and piperacillin, useful for their activity against Gram-negative bacteria. However, the usefulness of the \u03b2-lactam ring was such that related antibiotics, including the mecillinams, the carbapenems, and, most important, the cephalosporins, still retain it at the center of their structures.<ref>{{cite journal | vauthors = James CW, Gurk-Turner C | title = Cross-reactivity of beta-lactam antibiotics | journal = Proceedings | volume = 14 | issue = 1 | pages = 106\u20137 | date = January 2001 | pmid = 16369597 | pmc = 1291320 | doi = 10.1080/08998280.2001.11927741 }}</ref>"}},
{"article_title": "Polonium", "pageid": "23325", "revid": "1062392753", "timestamp": "2021-12-28T05:35:54Z", "history_paths": [["Polonium --- Introduction ---", "History"]], "categories": ["polonium", "chemical elements", "chalcogens", "post-transition metals", "element toxicology", "iarc group 1 carcinogens", "science and technology in poland", "marie curie", "pierre curie"], "heading_tree": {"Polonium --- Introduction ---": {"Characteristics": {"Solid state form": {}, "Chemistry": {"Compounds": {}}, "Isotopes": {}}, "History": {}, "Occurrence and production": {}, "Applications": {}, "Biology and toxicity": {"Overview": {}, "Acute effects": {}, "Long term (chronic) effects": {}, "Regulatory exposure limits and handling": {}, "Cases of poisoning": {"20th century": {}, "21st century": {}}, "Treatment": {}, "Detection in biological specimens": {}, "Occurrence in humans and the biosphere": {}, "Tobacco": {}, "Food": {}}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Polonium --- Introduction ---|History": "Tentatively called "[[Radium#History|radium F]]", polonium was discovered by [[Marie Curie|Marie]] and Pierre Curie in July 1898,<ref name="c1">{{cite journal|author1=Curie, P. |author2=Curie, M. |title=Sur une substance nouvelle radio-active, contenue dans la pechblende |trans-title=On a new radioactive substance contained in pitchblende |language=fr |journal=Comptes Rendus |volume=127 |pages=175\u2013178 |date=1898 |url=http://www.academie-sciences.fr/activite/archive/dossiers/Curie/Curie_pdf/CR1898_p175_178.pdf |url-status=unfit |archive-url=https://web.archive.org/web/20130723022419/http://www.academie-sciences.fr/activite/archive/dossiers/Curie/Curie_pdf/CR1898_p175_178.pdf |archive-date=July 23, 2013 }} [http://web.lemoyne.edu/~giunta/curiespo.html English translation.]</ref><ref>{{Cite web|url=http://elements.vanderkrogt.net/element.php?sym=po|title=84. Polonium - Elementymology & Elements Multidict|last=Krogt|first=Peter van der|website=elements.vanderkrogt.net|access-date=2017-04-26}}</ref> and was named after Marie Curie's native land of [[Poland]] ({{lang-la|Polonia}}).<ref>{{cite journal\n| title = Borders of the Nuclear World \u2013 100 Years After Discovery of Polonium\n| last = Pf\u00fctzner | first =M.\n| journal = Acta Physica Polonica B\n| volume = 30\n| issue = 5 | date = 1999\n| page= 1197\n| bibcode =1999AcPPB..30.1197P}}</ref><ref>{{cite journal\n| title = The centennial of the 1903 Nobel Prize for physics\n| last = Adloff | first = J. P.\n| journal =  Radiochimica Acta\n| volume = 91\n| issue = 12\u20132003\n| pages=681\u2013688\n| date=2003\n| doi = 10.1524/ract.91.12.681.23428| s2cid = 120150862 }}</ref> Poland at the time was under [[Russian Empire|Russian]], [[German Empire|German]], and [[Austro-Hungarian Empire|Austro-Hungarian]] [[Partitions of Poland|partition]], and did not exist as an independent country. It was Curie's hope that naming the element after her native land would publicize its lack of independence.<ref name="Przemysl" /> Polonium may be the first element named to highlight a political controversy.<ref name="Przemysl">{{cite journal\n| title = Chemical and Polish aspects of polonium and radium discovery\n| last = Kabzinska | first =K.\n| journal = Przemys\u0142 Chemiczny\n| volume = 77\n| date = 1998\n| pages = 104\u2013107\n| issue = 3}}</ref>\n\nThis element was the first one discovered by the Curies while they were investigating the cause of [[uraninite|pitchblende]] [[radioactivity]]. Pitchblende, after removal of the radioactive elements [[uranium]] and [[thorium]], was more radioactive than the uranium and thorium combined. This spurred the Curies to search for additional radioactive elements. They first separated out polonium from pitchblende in July 1898, and five months later, also isolated [[radium]].<ref name="nbb" /><ref name="c1" /><ref name="c2">{{cite journal|author1=Curie, P. |author2=Curie, M. |author3=B\u00e9mont, G. |title=Sur une nouvelle substance fortement radio-active contenue dans la pechblende |trans-title=On a new, strongly radioactive substance contained in pitchblende |language=fr |journal=Comptes Rendus |volume=127 |pages=1215\u20131217 |date=1898 |url=http://www.academie-sciences.fr/activite/archive/dossiers/Curie/Curie_pdf/CR1898_p1215_1217.pdf |url-status=unfit |archive-url=https://web.archive.org/web/20130722232602/http://www.academie-sciences.fr/activite/archive/dossiers/Curie/Curie_pdf/CR1898_p1215_1217.pdf |archive-date=July 22, 2013 }} [http://www.aip.org/history/curie/discover.htm English translation]</ref> German scientist [[Willy Marckwald]] successfully isolated 3 milligrams of polonium in 1902, though at the time he believed it was a new element, which he dubbed "radio-tellurium", and it was not until 1905 that it was demonstrated to be the same as polonium.<ref>{{cite journal | title = Polonium and Radio-Tellurium | journal = Nature | volume = 73 | issue = 549 | pages = 549 |date = 1906 | doi = 10.1038/073549b0| bibcode = 1906Natur..73R.549. | doi-access = free }}</ref><ref>{{cite book |last = Neufeldt |first = Sieghard | title = Chronologie Chemie: Entdecker und Entdeckungen | publisher = John Wiley & Sons | year = 2012 | isbn = 9783527662845 | url = {{Google books|0lFQjLAlgC0C|plainurl=y|page=115}} }}</ref>\n\nIn the United States, polonium was produced as part of the [[Manhattan Project]]'s [[Dayton Project]] during [[World War II]]. Polonium and [[beryllium]] were the key ingredients of the '[[Modulated neutron initiator#Urchin|Urchin]]' initiator at the center of the bomb's spherical [[Pit (nuclear weapon)|pit]].<ref name="nwfaq41">[http://nuclearweaponarchive.org/Nwfaq/Nfaq4-1.html Nuclear Weapons FAQ, Section 4.1, Version 2.04: 20 February 1999]. Nuclearweaponarchive.org. Retrieved on 2013-04-28.</ref> 'Urchin' initiated the [[Nuclear fission|nuclear chain reaction]] at the moment of [[prompt-critical]]ity to ensure that the weapon did not [[Fizzle (nuclear test)|fizzle]]. 'Urchin' was used in early U.S. weapons; subsequent U.S. weapons utilized a pulse neutron generator for the same purpose.<ref name="nwfaq41" />\n\nMuch of the basic physics of polonium was [[classified information|classified]] until after the war. The fact that it was used as an initiator was classified until the 1960s.<ref>[https://fas.org/sgp/othergov/doe/rdd-7.html#I16 RESTRICTED DATA DECLASSIFICATION DECISIONS, 1946 TO THE PRESENT (RDD-7)], January 1, 2001, U.S. Department of Energy Office of Declassification, via fas.org</ref>\n\nThe [[United States Atomic Energy Commission|Atomic Energy Commission]] and the [[Manhattan Project]] funded [[human experimentation in the United States|human experiments]] using polonium on five people at the [[University of Rochester]] between 1943 and 1947. The people were administered between {{convert|9|and|22|\u00b5Ci|kBq|lk=on}} of polonium to study its [[excretion]].<ref name="congress1986">[http://contentdm.library.unr.edu/cdm4/item_viewer.php?CISOROOT=/conghear&CISOPTR=102&CISOBOX=1&REC=1#metajump American nuclear guinea pigs: three decades of radiation experiments on U.S. citizens] {{Webarchive|url=https://web.archive.org/web/20130730200210/http://contentdm.library.unr.edu/cdm4/item_viewer.php?CISOROOT=%2Fconghear&CISOPTR=102&CISOBOX=1&REC=1#metajump |date=2013-07-30 }}. United States. Congress. House. of the Committee on Energy and Commerce. Subcommittee on Energy Conservation and Power, published by U.S. Government Printing Office, 1986, Identifier Y 4.En 2/3:99-NN, Electronic Publication Date 2010, at the University of Nevada, Reno, unr.edu</ref><ref name="nes1950">"Studies of polonium metabolism in human subjects", Chapter 3 in ''Biological Studies with Polonium, Radium, and Plutonium'', National, Nuclear Energy Series, Volume VI-3, McGraw-Hill, New York, 1950, cited in "American Nuclear Guinea Pigs ...", 1986 House Energy and Commerce committee report</ref><ref>Moss, William and Eckhardt, Roger (1995) [https://fas.org/sgp/othergov/doe/lanl/pubs/00326640.pdf "The Human Plutonium Injection Experiments"], Los Alamos Science, Number 23.</ref>"}},
{"article_title": "Polymerase chain reaction", "pageid": "23647", "revid": "1062816088", "timestamp": "2021-12-30T18:27:50Z", "history_paths": [["Polymerase chain reaction --- Introduction ---", "History"]], "categories": ["polymerase chain reaction", "molecular biology", "laboratory techniques", "dna profiling techniques", "amplifiers", "roche", "biotechnology", "molecular biology techniques", "american inventions"], "heading_tree": {"Polymerase chain reaction --- Introduction ---": {"Principles": {"Procedure": {}, "Stages": {}}, "Optimization": {}, "Applications": {"Selective DNA isolation": {}, "Amplification and quantification of DNA": {}, "Medical and diagnostic applications": {}, "Infectious disease applications": {}, "Forensic applications": {}, "Research applications": {}}, "Advantages": {}, "Limitations": {}, "Variations": {}, "History": {"Patent disputes": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Polymerase chain reaction --- Introduction ---|History": "[[File:Primers RevComp.svg|thumb|Diagrammatic representation of an example primer pair. The use of primers in an in vitro assay to allow DNA synthesis was a major innovation that allowed the development of PCR.]]\n{{Main|History of polymerase chain reaction}}\n\nThe heat-resistant enzymes that are a key component in polymerase chain reaction were discovered in the 1960s as a product of a microbial life form that lived in the superheated waters of [[Yellowstone National Park|Yellowstone]]'s Mushroom Spring.<ref>{{Cite web|title=Key ingredient in coronavirus tests comes from Yellowstone's lakes|url=https://www.nationalgeographic.com/science/2020/03/key-ingredient-in-coronavirus-tests-comes-from-yellowstone/|date=2020-03-31|website=Science|language=en|access-date=2020-05-13}}</ref>\n\nA 1971 paper in the ''[[Journal of Molecular Biology]]'' by [[Kjell Kleppe]] and co-workers in the laboratory of [[Har Gobind Khorana|H. Gobind Khorana]] first described a method of using an enzymatic assay to replicate a short DNA template with primers ''in vitro''.<ref>{{cite journal | vauthors = Kleppe K, Ohtsuka E, Kleppe R, Molineux I, Khorana HG | title = Studies on polynucleotides. XCVI. Repair replications of short synthetic DNA's as catalyzed by DNA polymerases | journal = Journal of Molecular Biology | volume = 56 | issue = 2 | pages = 341\u201361 | date = March 1971 | pmid = 4927950 | doi = 10.1016/0022-2836(71)90469-4 }}</ref> However, this early manifestation of the basic PCR principle did not receive much attention at the time and the invention of the polymerase chain reaction in 1983 is generally credited to [[Kary Mullis]].<ref>{{cite book|last=Rabinow|first=Paul|author-link=Paul Rabinow|year=1996|title=Making PCR: A Story of Biotechnology|publisher=University of Chicago Press|location=Chicago|isbn=978-0-226-70146-2|url-access=registration|url=https://archive.org/details/makingpcrstoryof00rabi/mode/1up}}</ref>{{Page needed|date=December 2021|reason=Rabinow in fact distinguishes between the "invention" of PCR and the "concept" of PCR in the introduction}}\n\n[[File:Baby Blue - a prototype polymerase chain reaction (PCR), c 1986. (9663810586).jpg|thumb|right|"Baby Blue", a 1986 prototype machine for doing PCR]]\nWhen Mullis developed the PCR in 1983, he was working in [[Emeryville, California|Emeryville]], California for [[Cetus Corporation]], one of the first [[biotechnology]] companies, where he was responsible for synthesizing short chains of DNA. Mullis has written that he conceived the idea for PCR while cruising along the [[California State Route 1|Pacific Coast Highway]] one night in his car.<ref name=Mullis>{{cite book|last=Mullis|first=Kary|author-link=Kary Mullis|year=1998|title=Dancing Naked in the Mind Field|publisher=Pantheon Books|location=New York|isbn=978-0-679-44255-4|url-access=registration|url=https://archive.org/details/dancingnakedinmi00mull}}</ref> He was playing in his mind with a new way of analyzing changes (mutations) in DNA when he realized that he had instead invented a method of amplifying any DNA region through repeated cycles of duplication driven by DNA polymerase. In ''[[Scientific American]]'', Mullis summarized the procedure: "Beginning with a single molecule of the genetic material DNA, the PCR can generate 100 billion similar molecules in an afternoon. The reaction is easy to execute. It requires no more than a test tube, a few simple reagents, and a source of heat."<ref>{{cite journal | vauthors = Mullis KB | title = The unusual origin of the polymerase chain reaction | journal = Scientific American | volume = 262 | issue = 4 | pages = 56\u201361, 64\u201365 | date = April 1990 | pmid = 2315679 | doi = 10.1038/scientificamerican0490-56 | bibcode = 1990SciAm.262d..56M }}</ref> DNA fingerprinting was first used for [[paternity testing]] in 1988.<ref>{{cite journal | vauthors = Patidar M, Agrawal S, Parveen F, Khare P | title = Molecular insights of saliva in solving paternity dispute | journal = Journal of Forensic Dental Sciences | volume = 7 | issue = 1 | pages = 76\u201379 | date = 2015 | pmid = 25709326 | pmc = 4330625 | doi = 10.4103/0975-1475.150325 }}</ref>\n\nMullis has credited his use of [[LSD]] as integral to his development of PCR: "Would I have invented PCR if I hadn't taken LSD?  I seriously doubt it.  I could sit on a DNA molecule and watch the polymers go by.  I learnt that partly on psychedelic drugs."<ref>{{cite journal | vauthors = Nichols D, Barker E| title = Psychedelics | journal = Pharmacological Reviews | volume = 68 | issue = 2 | pages = 264\u2013355 | date = 2016 | pmid = 26841800 | pmc = 4813425 | doi = 10.1124/pr.115.011478 }}</ref>\n\nMullis and biochemist [[Michael Smith (chemist)|Michael Smith]], who had developed other essential ways of manipulating DNA,<ref>{{Cite web|url=https://www.nobelprize.org/prizes/chemistry/1993/press-release/|title=The Nobel Prize in Chemistry 1993|website=NobelPrize.org}}</ref> were jointly awarded the [[Nobel Prize in Chemistry]] in 1993, seven years after Mullis and his colleagues at Cetus first put his proposal to practice.<ref name="Kary Mullis Nobel Lecture">{{Cite web|url=https://www.nobelprize.org/prizes/chemistry/1993/mullis/lecture/|title=The Nobel Prize in Chemistry 1993|website=NobelPrize.org}}</ref> Mullis's 1985 paper with R. K. Saiki and H. A. Erlich, "Enzymatic Amplification of \u03b2-globin Genomic Sequences and Restriction Site Analysis for Diagnosis of Sickle Cell Anemia"\u2014the polymerase chain reaction invention (PCR)\u2014was honored by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society in 2017.<ref name="breakthrough">{{cite web|title=Citations for Chemical Breakthrough Awards 2017 Awardees|url=http://www.scs.illinois.edu/~mainzv/HIST/awards/CCB-2017_Awardees.php|website=Division of the History of Chemistry|access-date=12 March 2018}}</ref><ref name="Saiki1"/>\n\nAt the core of the PCR method is the use of a suitable [[DNA polymerase]] able to withstand the high temperatures of >{{convert|90|\u00b0C|\u00b0F|abbr=on}} required for separation of the two DNA strands in the [[DNA double helix]] after each [[DNA replication|replication]] cycle. The DNA polymerases initially employed for [[in vitro]] experiments presaging PCR were unable to withstand these high temperatures.<ref name="Saiki1"/> So the early procedures for DNA replication were very inefficient and time-consuming, and required large amounts of DNA polymerase and continuous handling throughout the process.\n\nThe discovery in 1976 of [[Taq polymerase|''Taq'' polymerase]]\u2014a DNA polymerase purified from the [[Thermophile|thermophilic bacterium]], ''[[Thermus aquaticus]]'', which naturally lives in hot ({{convert|50|to|80|C|F}}) environments<ref name="Chien et al."/> such as hot springs\u2014paved the way for dramatic improvements of the PCR method. The DNA polymerase isolated from ''T. aquaticus'' is stable at high temperatures remaining active even after DNA denaturation,<ref name="Lawyer et al."/> thus obviating the need to add new DNA polymerase after each cycle.<ref name="Saiki2"/> This allowed an automated thermocycler-based process for DNA amplification.\n\n The PCR technique was patented by [[Kary Mullis]] and assigned to [[Cetus Corporation]], where Mullis worked when he invented the technique in 1983. The ''Taq'' polymerase enzyme was also covered by patents. There have been several high-profile lawsuits related to the technique, including an unsuccessful lawsuit brought by [[DuPont]]. The Swiss pharmaceutical company [[Hoffmann-La Roche]] purchased the rights to the patents in 1992 and currently{{when|date=October 2020}} holds those that are still protected.\n\nA related patent battle over the ''Taq'' polymerase enzyme is still ongoing in several jurisdictions around the world between Roche and [[Promega]]. The legal arguments have extended beyond the lives of the original PCR and ''Taq'' polymerase patents, which expired on 28 March 2005.<ref>{{cite journal|url=https://www.genengnews.com/magazine/49/advice-on-how-to-survive-the-taq-wars/ |title=Advice on How to Survive the Taq Wars|journal=GEN Genetic Engineering News \u2013 Biobusiness Channel|date=1 May 2006 |volume=26|issue= 9}}</ref>"}},
{"article_title": "Plug-in (computing)", "pageid": "23659", "revid": "1039455044", "timestamp": "2021-08-18T20:17:23Z", "history_paths": [["Plug-in (computing) --- Introduction ---", "History"]], "categories": ["application programming interfaces", "software add-ons", "technology neologisms"], "heading_tree": {"Plug-in (computing) --- Introduction ---": {"Purpose and examples": {}, "Mechanism": {}, "Mozilla definition": {}, "History": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Plug-in (computing) --- Introduction ---|History": "In the mid 1970s, the [[EDT (Univac)|EDT]] [[text editor]] ran on the [[Unisys]] [[VS/9]] [[operating system]] using the [[UNIVAC Series 90]] mainframe computer. It allowed a program from the editor and access the in-memory edit buffer.<ref>''EDT Text Editor Reference Manual'', [[Cinnaminson, New Jersey]]: [[Unisys Corporation]], 1975</ref>  The plug-in executable could call the editor to inspect and change the text. The [[University of Waterloo]] Fortran compiler used this to allow interactive compilation of [[Fortran]] programs.\n\nEarly personal computer software with plug-in capability included HyperCard and [[QuarkXPress]] on the [[Apple Macintosh]], both released in 1987. In 1988, [[Silicon Beach Software]] included plug-in capability in [[Digital Darkroom]] and [[SuperPaint]], and Ed Bomke coined the term ''plug-in''.{{citation needed|date=September 2014}}"}},
{"article_title": "Photolithography", "pageid": "23748", "revid": "1059672269", "timestamp": "2021-12-10T21:49:06Z", "history_paths": [["Photolithography --- Introduction ---", "History"]], "categories": ["lithography (microfabrication)", "microtechnology"], "heading_tree": {"Photolithography --- Introduction ---": {"History": {}, "Basic procedure": {"Cleaning": {}, "Preparation": {}, "Photoresist application": {}, "Exposure and developing": {}, "Etching": {}, "Photoresist removal": {}}, "Exposure (\"printing\") systems": {"Contact and proximity": {}, "Projection": {}}, "Photomasks": {}, "Resolution in projection systems": {}, "Stochastic effects": {}, "Light sources": {}, "Experimental methods": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Photolithography --- Introduction ---|History": "The root words ''photo'', ''litho'', and ''graphy'' all have Greek origins, with the meanings 'light', 'stone' and 'writing' respectively. As suggested by the name compounded from them, ''photolithography'' is a printing method (originally based on the use of limestone printing plates) in which light plays an essential role. In the 1820s, [[Nicephore Niepce]] invented a [[Photography|photographic]] process that used [[Bitumen of Judea]], a natural asphalt, as the first [[photoresist]]. A thin coating of the bitumen on a sheet of metal, glass or stone became less soluble where it was exposed to light; the unexposed parts could then be rinsed away with a suitable solvent, baring the material beneath, which was then chemically etched in an acid bath to produce a printing plate. The light-sensitivity of bitumen was very poor and very long exposures were required, but despite the later introduction of more sensitive alternatives, its low cost and superb resistance to strong acids prolonged its commercial life into the early 20th century. In 1940, Oskar S\u00fc\u00df created a ''positive'' photoresist by using [[diazonaphthoquinone]], which worked in the opposite manner: the coating was initially insoluble and was rendered soluble where it was exposed to light.<ref>{{cite journal|author =Willson, C. G., Dammel, R. R., and Reiser, A|title=Photoresist materials: a historical perspective|journal= [[Proc. SPIE 3049|Advances in Resist Technology and Processing XIV]]|volume=3049|page=28|year=1997|doi=10.1117/12.275826|bibcode=1997SPIE.3049...28W|s2cid=136616549|editor1-last=Tarascon-Auriol|editor1-first=Regine G}}</ref> In 1954, Louis Plambeck Jr. developed the Dycryl polymeric letterpress plate, which made the platemaking process faster.<ref>{{cite web | title=Lithography | url=http://www.lib.udel.edu/ud/spec/exhibits/color/lithogr.htm}}</ref>\n\nIn 1952, the U.S. military assigned Jay W. Lathrop and James R. Nall at the [[National Bureau of Standards]] (later the [[Harry Diamond Laboratories|U.S. Army Diamond Ordnance Fuze Laboratory]], which eventually merged to form the now-present [[United States Army Research Laboratory|Army Research Laboratory]]) with the task of finding a way to reduce the size of electronic circuits in order to better fit the necessary circuitry in the limited space available inside a [[proximity fuze]].<ref name=":0">{{Cite journal|title=The Diamond Ordnance Fuze Laboratory's Photolithographic Approach to Microcircuits - IEEE Journals & Magazine|journal=IEEE Annals of the History of Computing|volume=35|pages=48\u201355|language=en-US|doi=10.1109/MAHC.2011.83|year=2013|last1=Lathrop|first1=Jay W.|s2cid=2562671}}</ref> Inspired by the application of photoresist, a photosensitive liquid used to mark the boundaries of rivet holes in metal aircraft wings, Nall determined that a similar process can be used to protect the germanium in the transistors and even pattern the surface with light.<ref name=":1">{{Cite book|title=Eureka: How Invention Happens|last=Weightman|first=Gavin|publisher=Yale University Press|year=2015|isbn=978-0300192087|pages=[https://archive.org/details/eurekahowinventi0000weig/page/178 178\u2013179]|url=https://archive.org/details/eurekahowinventi0000weig/page/178}}</ref> During development, Lathrop and Nall were successful in creating a 2D miniaturized hybrid integrated circuit with transistors using this technique.<ref name=":0" /> In 1958, during the IRE Professional Group on Electron Devices (PGED) conference in Washington, D.C., they presented the first paper to describe the fabrication of transistors using photographic techniques and adopted the term "photolithography" to describe the process, marking the first published use of the term to describe semiconductor device patterning.<ref name=":1" /><ref name=comus2018>{{Cite web|url=http://www.computerhistory.org/events/bio/Jay,Lathrop|title=Jay W. Lathrop {{!}} Computer History Museum|website=www.computerhistory.org|language=en|access-date=2018-06-18}}</ref>\n\nDespite the fact that photolithography of electronic components concerns etching metal duplicates, rather than etching stone to produce a "master" as in conventional lithographic printing, Lathrop and Nall chose the term "photolithography" over "photoetching" because the former sounded "high tech."<ref name=":0" /> A year after the conference, Lathrop and Nall's patent on photolithography was formally approved on June 9, 1959.<ref>{{Cite book|title=Makers of the Microchip: A Documentary History of Fairchild Semiconductor|last=L\u00e9cuyer|first=Christophe|publisher=The MIT Press|year=2010|isbn=978-0262014243}}</ref> Photolithography would later contribute to the development of the first semiconductor ICs as well as the first microchips.<ref name=":0" />"}},
{"article_title": "Python (programming language)", "pageid": "23862", "revid": "1062820388", "timestamp": "2021-12-30T18:55:29Z", "history_paths": [["Python (programming language) --- Introduction ---", "History"]], "categories": ["python (programming language)", "articles with example python (programming language) code", "class-based programming languages", "computational notebook", "computer science in the netherlands", "concurrent programming languages", "cross-platform free software", "cross-platform software", "dutch inventions", "dynamically typed programming languages", "educational programming languages", "high-level programming languages", "information technology in the netherlands", "multi-paradigm programming languages", "object-oriented programming languages", "programming languages", "programming languages created in 1991", "scripting languages", "text-oriented programming languages"], "heading_tree": {"Python (programming language) --- Introduction ---": {"History": {}, "Design philosophy and features": {}, "Syntax and semantics": {"Indentation": {}, "Statements and control flow": {}, "Expressions": {}, "Methods": {}, "Typing": {}, "Arithmetic operations": {}}, "Programming examples": {}, "Libraries": {}, "Development environments": {}, "Implementations": {"Reference implementation": {}, "Other implementations": {}, "Unsupported implementations": {}, "Cross-compilers to other languages": {}, "Performance": {}}, "Development": {}, "API documentation generators": {}, "Naming": {}, "Popularity": {}, "Uses": {}, "Languages influenced by Python": {}, "See also": {}, "References": {"Sources": {}}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Python (programming language) --- Introduction ---|History": "[[File:Guido van Rossum OSCON 2006 cropped.png|thumb|150px|The designer of Python, [[Guido van Rossum]], at [[O'Reilly Open Source Convention|OSCON]] 2006]]\n{{Main|History of Python}}\n\nPython was conceived in the late 1980s<ref name="venners-interview-pt-1" /> by [[Guido van Rossum]] at [[Centrum Wiskunde & Informatica]] (CWI) in the [[Netherlands]] as a successor to  the [[ABC (programming language)|ABC programming language]], which was inspired by [[SETL]],<ref name="AutoNT-12" /> capable of [[exception handling]] and interfacing with the [[Amoeba (operating system)|Amoeba]] operating system.<ref name="faq-created" /> Its implementation began in December 1989.<ref name="timeline-of-python" /> Van Rossum shouldered sole responsibility for the project, as the lead developer, until 12 July 2018, when he announced his "permanent vacation" from his responsibilities as Python's "[[benevolent dictator for life]]", a title the Python community bestowed upon him to reflect his long-term commitment as the project's chief decision-maker.<ref name="lj-bdfl-resignation" /> In January 2019, active Python core developers elected a five-member "Steering Council" to lead the project.<ref>{{cite web |title=PEP 8100 |url=https://www.python.org/dev/peps/pep-8100/ |publisher=Python Software Foundation |access-date=4 May 2019 |archive-date=4 June 2020 |archive-url=https://web.archive.org/web/20200604235027/https://www.python.org/dev/peps/pep-8100/ |url-status=live }}</ref><ref>{{Cite web|title=PEP 13 -- Python Language Governance|url=https://www.python.org/dev/peps/pep-0013/|access-date=2021-08-25|website=Python.org|language=en|archive-date=27 May 2021|archive-url=https://web.archive.org/web/20210527000035/https://www.python.org/dev/peps/pep-0013/|url-status=live}}</ref>\n\nPython 2.0 was released on 16 October 2000, with many major new features, including a [[cycle detection|cycle-detecting]] [[garbage collection (computer science)|garbage collector]] (in addition to [[reference counting]]) for [[memory management]] and support for [[Unicode]].<ref name="newin-2.0" />\n\nPython 3.0 was released on 3 December 2008. It was a major revision of the language that is not completely [[backward compatibility|backward-compatible]].<ref name="3.0-release" /> Many of its major features were [[backporting|backported]] to Python 2.6.x<ref name="pep-3000" /> and 2.7.x version series.  Releases of Python 3 include the <code>2to3</code> utility, which automates the translation of Python 2 code to Python 3.<ref>{{Cite web|title=2to3 \u2013 Automated Python 2 to 3 code translation|url=https://docs.python.org/3/library/2to3.html|access-date=2021-02-02|website=docs.python.org|archive-date=4 June 2020|archive-url=https://web.archive.org/web/20200604232823/https://docs.python.org/3/library/2to3.html|url-status=live}}</ref>\n\nPython 2.7's [[end-of-life (product)|end-of-life]] date was initially set at 2015 then postponed to 2020 out of concern that a large body of existing code could not easily be forward-ported to Python 3.<ref>{{cite web |url=https://legacy.python.org/dev/peps/pep-0373/ |title=PEP 373 -- Python 2.7 Release Schedule |work=python.org |access-date=9 January 2017 |archive-date=19 May 2020 |archive-url=https://web.archive.org/web/20200519075520/https://legacy.python.org/dev/peps/pep-0373/ |url-status=live }}</ref><ref>{{cite web |url=https://www.python.org/dev/peps/pep-0466/ |title=PEP 466 -- Network Security Enhancements for Python 2.7.x |work=python.org |access-date=9 January 2017 |archive-date=4 June 2020 |archive-url=https://web.archive.org/web/20200604232833/https://www.python.org/dev/peps/pep-0466/ |url-status=live }}</ref>  No more security patches or other improvements will be released for it.<ref>{{Cite web|url=https://www.python.org/doc/sunset-python-2/|title=Sunsetting Python 2|website=Python.org|language=en|access-date=22 September 2019|archive-date=12 January 2020|archive-url=https://web.archive.org/web/20200112080903/https://www.python.org/doc/sunset-python-2/|url-status=live}}</ref><ref>{{Cite web|url=https://www.python.org/dev/peps/pep-0373/|title=PEP 373 -- Python 2.7 Release Schedule|website=Python.org|language=en|access-date=22 September 2019|archive-date=13 January 2020|archive-url=https://web.archive.org/web/20200113033257/https://www.python.org/dev/peps/pep-0373/|url-status=live}}</ref> With Python 2's [[end-of-life (product)|end-of-life]], only  Python 3.6.x<ref>{{Cite web|url=https://devguide.python.org/#status-of-python-branches|title=Python Developer's Guide \u2014 Python Developer's Guide|website=devguide.python.org|access-date=17 December 2019|archive-date=9 November 2020|archive-url=https://web.archive.org/web/20201109032501/https://devguide.python.org/#status-of-python-branches|url-status=live}}</ref> and later are supported.\n\nPython 3.9.2 and 3.8.8 were expedited<ref>{{Cite web|last=Langa|first=\u0141ukasz|date=2021-02-19|title=Python Insider: Python 3.9.2 and 3.8.8 are now available|url=https://pythoninsider.blogspot.com/2021/02/python-392-and-388-are-now-available.html|access-date=2021-02-26|website=Python Insider|archive-date=25 February 2021|archive-url=https://web.archive.org/web/20210225043834/https://pythoninsider.blogspot.com/2021/02/python-392-and-388-are-now-available.html|url-status=live}}</ref> as all versions of Python (including 2.7<ref>{{Cite web|title=Red Hat Customer Portal - Access to 24x7 support and knowledge|url=https://access.redhat.com/security/cve/cve-2021-3177|access-date=2021-02-26|website=access.redhat.com|archive-date=6 March 2021|archive-url=https://web.archive.org/web/20210306183700/https://access.redhat.com/security/cve/cve-2021-3177|url-status=live}}</ref>) had security issues, leading to possible [[remote code execution]]<ref>{{Cite web|title=CVE - CVE-2021-3177|url=https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3177|access-date=2021-02-26|website=cve.mitre.org|archive-date=27 February 2021|archive-url=https://web.archive.org/web/20210227192918/https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3177|url-status=live}}</ref> and [[cache poisoning|web cache poisoning]].<ref>{{Cite web|title=CVE - CVE-2021-23336|url=https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23336|access-date=2021-02-26|website=cve.mitre.org|archive-date=24 February 2021|archive-url=https://web.archive.org/web/20210224160700/https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23336|url-status=live}}</ref>"}},
{"article_title": "Public-key cryptography", "pageid": "24222", "revid": "1059388010", "timestamp": "2021-12-09T04:32:14Z", "history_paths": [["Public-key cryptography --- Introduction ---", "History"]], "categories": ["public-key cryptography", "anonymity networks", "cryptographic software", "cryptographic protocols", "cryptography", "banking technology", "public key infrastructure", "network architecture"], "heading_tree": {"Public-key cryptography --- Introduction ---": {"Description": {}, "Applications": {"Hybrid Cryptosystems": {}}, "Weaknesses": {"Algorithms": {}, "Alteration of public keys": {}, "Public key infrastructure": {}}, "Examples": {}, "History": {"Anticipation": {}, "Classified discovery": {}, "Public discovery": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Public-key cryptography --- Introduction ---|History": "During the early [[history of cryptography]], two parties would rely upon a key that they would exchange by means of a secure, but non-cryptographic, method such as a face-to-face meeting, or a trusted courier. This key, which both parties must then keep absolutely secret, could then be used to exchange encrypted messages. A number of significant practical difficulties arise with this approach to [[key distribution|distributing keys]].\n\n In his 1874 book ''The Principles of Science'', [[William Stanley Jevons]]<ref>Jevons, William Stanley, [https://archive.org/stream/principlesofscie00jevorich#page/n166/mode/1up ''The Principles of Science: A Treatise on Logic and Scientific Method''] p. 141, Macmillan & Co., London, 1874, 2nd ed. 1877, 3rd ed. 1879. Reprinted with a foreword by [[Ernst Nagel]], Dover Publications, New York, NY, 1958.</ref> wrote:<blockquote>\nCan the reader say what two numbers multiplied together will produce the number [[William Stanley Jevons#Jevons's number|8616460799]]?<ref>This came to be known as "Jevons's number". The only nontrivial factor pair is 89681 \u00d7 96079.</ref> I think it unlikely that anyone but myself will ever know.<ref>[https://archive.org/stream/principlesofscie00jevorich#page/n165/mode/2up ''Principles of Science''], Macmillan & Co., 1874, p. 141.</ref></blockquote>\nHere he described the relationship of [[one-way function]]s to cryptography, and went on to discuss specifically the [[factorization]] problem used to create a [[trapdoor function]]. In July 1996, mathematician [[Solomon W. Golomb]] said: "Jevons anticipated a key feature of the RSA Algorithm for public key cryptography, although he certainly did not invent the concept of public key cryptography."<ref>{{cite journal |doi=10.1080/0161-119691884933 |year=1996 |last=Golob |first=Solomon W. |journal=Cryptologia |volume=20 |issue=3 |page=243|title=On Factoring Jevons' Number |s2cid=205488749 |url=https://semanticscholar.org/paper/0b3e9a0c0e8bf84413f49d3a4585c207f58da70e }}</ref>\n\n In 1970, [[James H. Ellis]], a British cryptographer at the UK [[Government Communications Headquarters]] (GCHQ), conceived of the possibility of "non-secret encryption", (now called public key cryptography), but could see no way to implement it.<ref>{{cite journal |last=Ellis |first=James H. |title=THE POSSIBILITY OF SECURE NON-SECRET DIGITAL ENCRYPTION |date=January 1970 |url=https://cryptocellar.org/cesg/possnse.pdf}}</ref><ref>{{cite news |last=Sawer |first=Patrick |title=The unsung genius who secured Britain's computer defences and paved the way for safe online shopping |journal=The Telegraph |date=11 March 2016 |url=https://www.newindianexpress.com/world/2016/mar/12/The-Anonymous-Researcher-Who-Held-the-Key-to-Cyber-Security-910751.html}}</ref> In 1973, his colleague [[Clifford Cocks]] implemented what has become known as the [[RSA (cryptosystem)|RSA encryption algorithm]], giving a practical method of "non-secret encryption", and in 1974 another GCHQ mathematician and cryptographer, [[Malcolm J. Williamson]], developed what is now known as [[Diffie\u2013Hellman key exchange]]. \nThe scheme was also passed to the USA's [[National Security Agency]].<ref name="zdnet"/> Both organisations had a military focus and only limited computing power was available in any case;  the potential of public key cryptography remained unrealised by either organization:\n<blockquote>\nI judged it most important for military use ... if you can share your key rapidly and electronically, you have a major advantage over your opponent. Only at the end of the evolution from [[Tim Berners-Lee|Berners-Lee]] designing an open internet architecture for [[CERN]], its adaptation and adoption for the [[Arpanet]] ... did public key cryptography realise its full potential.\n\n\u2014[[Ralph Benjamin]]<ref name="zdnet">{{cite web |url=http://www.zdnet.com/article/gchq-pioneers-on-birth-of-public-key-crypto/ |title=GCHQ pioneers on birth of public key crypto |first=Tom |last=Espiner |date=26 October 2010 |website=www.zdnet.com}}</ref>\n</blockquote>\nThese discoveries were not publicly acknowledged for 27 years, until the research was declassified by the British government in 1997.<ref name=singh>{{cite book |last=Singh |first=Simon |author-link=Simon Singh |title=The Code Book |publisher=Doubleday |year=1999 |pages=[https://archive.org/details/codebookevolutio00sing/page/279 279]\u2013292|title-link=The Code Book }}</ref>\n\n In 1976, an asymmetric key cryptosystem was published by [[Whitfield Diffie]] and [[Martin Hellman]] who, influenced by [[Ralph Merkle]]'s work on public key distribution, disclosed a method of public key agreement. This method of key exchange, which uses [[Finite field#Applications|exponentiation in a finite field]], came to be known as [[Diffie\u2013Hellman key exchange]].<ref name="Diffie 1976">{{Cite journal|last1=Diffie|first1=Whitfield|last2=Hellman|first2=Martin E.|author-link2=Martin Hellman|date=November 1976|title=New Directions in Cryptography|url=//ee.stanford.edu/%7Ehellman/publications/24.pdf|url-status=live|journal=[[IEEE Transactions on Information Theory]]|volume=22|issue=6|pages=644\u2013654|doi=10.1109/TIT.1976.1055638|archive-url=https://web.archive.org/web/20141129035850/https://ee.stanford.edu/%7Ehellman/publications/24.pdf|archive-date=2014-11-29|author-link1=Whitfield Diffie|citeseerx=10.1.1.37.9720}}</ref> This was the first published practical method for establishing a shared secret-key over an authenticated (but not confidential) communications channel without using a prior shared secret. Merkle's "public key-agreement technique" became known as [[Ralph Merkle puzzle cryptographic system|Merkle's Puzzles]], and was invented in 1974 and only published in 1978.\n\nIn 1977, a generalization of Cocks' scheme was independently invented by [[Ron Rivest]], [[Adi Shamir]] and [[Leonard Adleman]], all then at [[Massachusetts Institute of Technology|MIT]]. The latter authors published their work in 1978 in [[Martin Gardner]]'s [[Scientific American]] column, and the algorithm came to be known as [[RSA (cryptosystem)|RSA]], from their initials.<ref name="rsa">{{cite journal\n | last1 = Rivest | first1 = R.\n | last2 = Shamir | first2 = A.\n | last3 = Adleman | first3 = L.\n | url = http://people.csail.mit.edu/rivest/Rsapaper.pdf\n | title = A Method for Obtaining Digital Signatures and Public-Key Cryptosystems\n | journal = [[Communications of the ACM]]\n | volume = 21  | issue = 2 | pages = 120\u2013126 | date = February 1978\n | doi = 10.1145/359340.359342| citeseerx = 10.1.1.607.2677\n | s2cid = 2873616\n }}</ref> RSA uses [[modular exponentiation|exponentiation modulo]] a product of two very large [[prime number|primes]], to encrypt and decrypt, performing both public key encryption and public key digital signatures. Its security is connected to the extreme difficulty of [[integer factorization|factoring large integers]], a problem for which there is no known efficient general technique (though prime factorization may be obtained through brute-force attacks; this grows much more difficult the larger the prime factors are). A description of the algorithm was published in the [[List of Martin Gardner Mathematical Games columns|Mathematical Games]] column in the August 1977 issue of [[Scientific American]].<ref>{{cite journal |url=http://www.msri.org/people/members/sara/articles/rsa.pdf |journal=SIAM News |volume=36 |issue=5 |date=June 2003 |title=Still Guarding Secrets after Years of Attacks, RSA Earns Accolades for its Founders |first=Sara |last=Robinson }}</ref>\n\nSince the 1970s, a large number and variety of encryption, digital signature, key agreement, and other techniques have been developed, including the [[Rabin cryptosystem]], [[ElGamal encryption]], [[Digital Signature Algorithm|DSA]] - and [[elliptic curve cryptography]]."}},
{"article_title": "PAL", "pageid": "24438", "revid": "1062838412", "timestamp": "2021-12-30T21:06:34Z", "history_paths": [["PAL --- Introduction ---", "History"]], "categories": ["itu-r recommendations", "television technology", "television terminology", "television transmission standards", "video formats"], "heading_tree": {"PAL --- Introduction ---": {"Geographic reach": {}, "History": {}, "Colour encoding": {"PAL signal details": {}}, "PAL broadcast systems": {"System A": {}, "PAL-B/G/D/K/I": {}, "PAL-M (Brazil)": {}, "PAL-N (Argentina, Paraguay and Uruguay){{anchor|PALN}}": {"VHS and DVD players": {}}, "PAL-L": {}}, "Multisystem TVs": {}, "Home devices and PAL 60": {}, "PAL vs. NTSC": {}, "PAL vs. SECAM": {}, "Countries and territories using PAL": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"PAL --- Introduction ---|History": "{{Refimprove-sect|date=May 2021}}\nIn the 1950s, the Western European countries began plans to introduce colour television, and were faced with the problem that the [[NTSC]] standard demonstrated several weaknesses, including colour tone shifting under poor transmission conditions, which became a major issue considering Europe's geographical and weather-related particularities. To overcome NTSC's shortcomings, alternative standards were devised, resulting in the development of the PAL and SECAM standards. The goal was to provide a colour TV standard for the European picture frequency of 50 [[field (video)|fields]] per second (50 [[hertz]]), and finding a way to eliminate the problems with NTSC.\n\nPAL was developed by [[Walter Bruch]] at [[Telefunken]] in Hanover, [[West Germany]], with important input from {{Interlanguage link multi|Gerhard Mahler|de|3=Gerhard Mahler (Fernsehtechniker)|lt=Gerhard Mahler}}. The format was patented by Telefunken in 1962, citing Bruch as inventor, and unveiled to members of the [[European Broadcasting Union]] (EBU) on 3 January 1963. When asked why the system was named "PAL" and not "Bruch" the inventor answered that a "Bruch system" would probably not have sold very well ("Bruch" is the German word for "breakage"). The first broadcasts began in the [[United Kingdom]] in July 1967, followed by West Germany later that year.<ref name="ITU">The standard that defines the PAL system was last published by the [[International Telecommunication Union]] in 1998 and has the title [https://www.itu.int/rec/R-REC-BT.470/en ''Recommendation ITU-R BT.470, Conventional Television Systems'']</ref> The one BBC channel initially using the broadcast standard was [[BBC Two|BBC2]], which had been the first UK TV service to introduce "625-lines" in 1964. Telefunken PALcolour 708T was the first PAL commercial TV set. It was followed by Loewe-Farbfernseher S 920 & F 900.\n\nTelefunken was later bought by the French electronics manufacturer [[Technicolor SA|Thomson]]. Thomson also bought the ''Compagnie G\u00e9n\u00e9rale de T\u00e9l\u00e9vision'' where [[Henri de France]] developed SECAM, the first [[European Committee for Standardization|European Standard]] for colour television. Thomson, now called Technicolour SA, also owns the [[RCA (trademark)|RCA brand]] and licences it to other companies; [[RCA|Radio Corporation of America]], the originator of that brand, created the NTSC colour TV standard before Thomson became involved.\n\nWith the introduction of digital broadcasts and signal sources (ex: DVDs, game consoles), the term PAL was used imprecisely to refer to the 625-line/50 Hz ([[576i]]) television system in general, to differentiate from the 525-line/60 Hz ([[480i]]) system generally used with NTSC. For example, [[DVD]]s were labelled as PAL or NTSC (referring to the line count and frame rate) even though technically the discs carry neither PAL nor NTSC encoded signal. These devices would still have analog outputs (ex; composite video output), and would convert the digital signals (576i or 480i) to the analog standards to assure compatibility. CCIR 625/50 and EIA 525/60 are the proper names for these (line count and field rate) standards; PAL and NTSC on the other hand are methods of encoding colour information in the signal."}},
{"article_title": "Pendulum clock", "pageid": "24989", "revid": "1060793234", "timestamp": "2021-12-17T18:09:31Z", "history_paths": [["Pendulum clock --- Introduction ---", "History"]], "categories": ["clocks", "clock designs", "pendulums", "inventions by christiaan huygens", "oscillators", "science and technology in the dutch republic"], "heading_tree": {"Pendulum clock --- Introduction ---": {"History": {}, "Mechanism": {}, "Gravity-swing pendulum": {"Temperature compensation": {}, "Atmospheric drag": {}, "Leveling and \"beat\"": {}, "Local gravity": {}}, "Torsion pendulum": {}, "Escapement": {}, "Time indication": {}, "Styles": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Pendulum clock --- Introduction ---|History": "{{multiple image\n| footer   = The first pendulum clock, invented by [[Christiaan Huygens]] in 1656\n| image1   = Huygens first pendulum clock - front view.png\n| width1   = 120\n| image2   = Huygens first pendulum clock.png\n| width2   = 112\n}}\n\nThe first pendulum clock was invented in 1656 by [[Dutch (ethnic group and nation)|Dutch]] scientist and inventor [[Christiaan Huygens]], and patented the following year.  Huygens contracted the construction of his clock designs to clockmaker [[Salomon Coster]], who actually built the clock.  Huygens was inspired by investigations of pendulums by [[Galileo Galilei]] beginning around 1602.  Galileo discovered the key property that makes pendulums useful timekeepers: [[wikt:isochronous|isochronism]], which means that the [[Frequency|period]] of swing of a pendulum is approximately the same for different sized swings.<ref>{{cite web\n|title=Huygens' Clocks\n|work=Stories\n|publisher=Science Museum, London, UK\n|url=http://www.sciencemuseum.org.uk/onlinestuff/stories/huygens_clocks.aspx \n|access-date=2007-11-14}}</ref><ref>{{cite web\n|title=Pendulum Clock\n|work=The Galileo Project\n|publisher=Rice Univ.\n|url=http://galileo.rice.edu/sci/instruments/pendulum.html\n|access-date=2007-12-03}}</ref>  Galileo in 1637 described to his son a mechanism which could keep a pendulum swinging, which has been called the first pendulum clock design ''(picture at top)''.  It was partly constructed by his son in 1649, but neither lived to finish it.<ref>A modern reconstruction can be seen at {{cite web\n|title=Pendulum clock designed by Galileo, Item #1883-29\n|work=Time Measurement\n|publisher=Science Museum, London, UK|url=http://www.sciencemuseum.org.uk/objects/time_measurement/1883-29.aspx \n|access-date=2007-11-14}}</ref>   The introduction of the pendulum, the first [[harmonic oscillator]] used in timekeeping, increased the accuracy of clocks enormously, from about 15 minutes per day to 15 seconds per day<ref>{{cite web\n|last=Bennet\n|first=Matthew\n|title=Huygens' Clocks\n|year=2002\n|publisher=Georgia Institute of Technology\n|url=http://www.physics.gatech.edu/research/schatz/pubs/royclocks2.pdf\n|access-date=2007-12-04 |archive-url = https://web.archive.org/web/20080410084732/http://www.physics.gatech.edu/research/schatz/pubs/royclocks2.pdf <!-- Bot retrieved archive --> |archive-date = 2008-04-10|display-authors=etal}}, p.3, also published in ''Proceedings of the Royal Society of London, ''A'' '''458''', 563\u2013579</ref> leading to their rapid spread as existing '[[verge and foliot]]' clocks were retrofitted with pendulums.\n\n[[Image:Edward East winged lantern clock.jpg|thumb|left|upright|A [[lantern clock]] that has been converted to use a pendulum. To accommodate the wide pendulum swings caused by the [[verge escapement]], "wings" have been added on the sides]]\n[[File:Grandfather clock q.jpg|thumb|upright=0.6|Grandfather clock]]\n{{multiple image\n| align = right\n| direction = horizontal\n| header   =\n| image1   = Riefler clock NIST.jpg \n| width1   = 72\n| image2   = Shortt Synchronome free pendulum clock.jpg\n| width2   = 200\n| footer   = Some of the most accurate pendulum clocks: ''(left)'' [[Riefler clock|Riefler regulator clock]], that served as the US time standard from 1909 to 1929, ''(right)'' [[Shortt-Synchronome clock]], the most accurate pendulum clock ever manufactured, which served as the time standard during the 1930s. \n}}\n\nThese early clocks, due to their [[verge escapement]]s, had wide pendulum swings of 80\u2013100\u00b0.  In his 1673 analysis of pendulums, ''[[Horologium Oscillatorium]]'',  Huygens showed that wide swings made the pendulum inaccurate, causing its period, and thus the rate of the clock, to vary with unavoidable variations in the driving force provided by the [[movement (clockwork)|movement]].  Clockmakers' realization that only pendulums with small swings of a few degrees are [[isochronous (horology)|isochronous]] motivated the invention of the [[anchor escapement]] by [[Robert Hooke]] around 1658, which reduced the pendulum's swing to 4\u20136\u00b0.<ref>{{cite journal\n |last        = Headrick\n |first       = Michael\n |year        = 2002\n |title       = Origin and Evolution of the Anchor Clock Escapement\n |journal     = Control Systems Magazine\n |publisher   = Inst. of Electrical and Electronic Engineers\n |volume      = 22\n |issue       = 2\n |url         = http://www.geocities.com/mvhw/anchor.html\n |access-date  = 2007-06-06\n |archive-url  = https://web.archive.org/web/20091025120920/http://geocities.com/mvhw/anchor.html\n |archive-date = October 25, 2009\n |url-status     = dead\n}}</ref>  The anchor became the standard escapement used in pendulum clocks.  In addition to increased accuracy, the anchor's narrow pendulum swing allowed the clock's case to accommodate longer, slower pendulums, which needed less power and caused less wear on the movement.  The [[seconds pendulum]] (also called the Royal pendulum),  0.994 m (39.1 in) long,  in which the time period is two seconds, became widely used in quality clocks.  The long narrow clocks built around these pendulums, first made by William Clement around 1680, became known as [[grandfather clock]]s.  The increased accuracy resulting from these developments caused the minute hand, previously rare, to be added to clock faces beginning around 1690.<ref>Milham 1945, p. 190</ref>\n\nThe 18th and 19th century wave of [[horological]] innovation that followed the invention of the pendulum brought many improvements to pendulum clocks.  The [[deadbeat escapement]] invented in 1675 by [[Richard Towneley]] and popularized by [[George Graham (clockmaker)|George Graham]] around 1715 in his precision "regulator" clocks gradually replaced the anchor escapement<ref>Milham 1945, p.181, 441</ref> and is now used in most modern pendulum clocks.  Observation that pendulum clocks slowed down in summer brought the realization that [[thermal expansion]] and contraction of the pendulum rod with changes in temperature was a source of error. This was solved by the invention of temperature-compensated pendulums; the [[mercury pendulum]] by Graham in 1721 and the [[gridiron pendulum]] by [[John Harrison]] in 1726.<ref>Milham 1945, pp. 193\u2013195</ref>  With these improvements, by the mid-18th century precision pendulum clocks achieved accuracies of a few seconds per week.\n\nUntil the 19th century, clocks were handmade by individual craftsmen and were very expensive.  The rich ornamentation of pendulum clocks of this period indicates their value as status symbols of the wealthy.  The [[clockmaker]]s of each country and region in Europe developed their own distinctive styles.  By the 19th century, factory production of clock parts gradually made pendulum clocks affordable by middle-class families.\n\nDuring the [[Industrial Revolution]], the faster pace of life and scheduling of shifts and public transportation like trains depended on the more accurate timekeeping made possible by the pendulum.  Daily life was organized around the home pendulum clock.  More accurate pendulum clocks, called ''regulators'', were installed in places of business and [[railroad station]]s and used to schedule work and set other clocks.  The need for extremely accurate timekeeping in [[celestial navigation]] to determine [[longitude]] on ships during long sea voyages drove the development of the most accurate pendulum clocks, called ''astronomical regulators''.  These precision instruments, installed in [[naval observatory|naval observatories]] and kept accurate within a second by observation of [[star transit]]s overhead, were used to set [[marine chronometer]]s on naval and commercial vessels.  Beginning in the 19th century, astronomical regulators in naval observatories served as primary standards for national [[Time signal|time distribution services]] that distributed time signals over [[telegraph]] wires.<ref>Milham 1945, p.83</ref>  From 1909, US National Bureau of Standards (now [[NIST]]) based the US time standard on [[Riefler escapement|Riefler]] pendulum clocks, accurate to about 10 milliseconds per day.  In 1929 it switched to the [[Shortt-Synchronome clock|Shortt-Synchronome free pendulum clock]] before phasing in [[Quartz clock|quartz]] standards in the 1930s.<ref>{{cite web\n | date=April 30, 2002\n | url=http://physics.nist.gov/GenInt/Time/revol.html\n | title=A Revolution in Timekeeping\n | publisher=Time and Frequency Services, NIST \n | access-date=2007-05-29 |archive-url = https://web.archive.org/web/20070528005441/http://physics.nist.gov/GenInt/Time/revol.html <!-- Bot retrieved archive --> |archive-date = 2007-05-28}}</ref>\n<ref>{{cite conference\n |last        = Sullivan\n |first       = D.B.\n |title       = Time and frequency measurement at NIST: The first 100 years\n |year        = 2001\n |book-title   = 2001 IEEE Int'l Frequency Control Symp.\n |publisher   = National Institute of Standards and Technology\n |url         = http://tf.nist.gov/timefreq/general/pdf/1485.pdf\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20110927062444/http://tf.nist.gov/timefreq/general/pdf/1485.pdf\n |archive-date = 2011-09-27\n}}</ref>  With an error of less than one second per year, the Shortt was the most accurate commercially produced pendulum clock.<ref name="Jones">{{cite book   \n  | last = Jones\n  | first = Tony\n  | title = Splitting the Second: The Story of Atomic Time\n  | publisher = CRC Press\n  | year = 2000\n  | location = US\n  | pages = 30\n  | url = https://books.google.com/books?id=krZBQbnHTY0C&pg=PA30\n  | isbn = 978-0-7503-0640-9}}</ref><ref>{{cite book   \n  | last = Milham\n  | first = Willis I.\n  | title = Time and Timekeepers\n  | publisher = MacMillan\n  | year = 1945\n  | location = New York\n  | pages = 615\n  }}</ref><ref name="Marrison">{{cite journal\n |last        = Marrison\n |first       = Warren\n |title       = The Evolution of the Quartz Crystal Clock\n |journal     = Bell System Technical Journal\n |year        = 1948\n |volume      = 27\n |issue = 3\n |pages       = 510\u2013588\n |url         = http://www.ieee-uffc.org/main/history.asp?file=marrison\n |doi         = 10.1002/j.1538-7305.1948.tb01343.x\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20110717061023/http://www.ieee-uffc.org/main/history.asp?file=marrison\n |archive-date = 2011-07-17\n}}</ref><ref>{{cite web\n  | title = The Reifler and Shortt clocks\n  | publisher = JagAir Institute of Time and Technology\n  | url = http://www.clockvault.com/heritage/index.htm\n  | access-date = 2009-12-29}}</ref><ref name="Betts">{{cite web\n |last        = Betts\n |first       = Jonathan\n |title       = Expert's Statement, Case 6 (2008-09) William Hamilton Shortt regulator\n |work        = Export licensing hearing, Reviewing Committee on the Export of Works of Art and Objects of Cultural Interest\n |publisher   = UK Museums, Libraries, and Archives Council\n |date        = May 22, 2008\n |url         = http://www.mla.gov.uk/what/cultural/export/reviewing_cttee/~/media/Files/word/2009/RCEWA/Cases%202008-09/Case%206%202008-09%20Regulator/internet%20experts%20statement%20shortt.ashx\n |format      = DOC\n |access-date  = 2009-12-29\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20091025180404/http://www.mla.gov.uk/what/cultural/export/reviewing_cttee/~/media/Files/word/2009/RCEWA/Cases%202008-09/Case%206%202008-09%20Regulator/internet%20experts%20statement%20shortt.ashx\n |archive-date = October 25, 2009\n}}</ref>\n\nPendulum clocks remained the world standard for accurate timekeeping for 270 years, until the invention of the [[quartz clock]] in 1927, and were used as time standards through [[World War 2]].  The French Time Service included pendulum clocks in their ensemble of standard clocks until 1954.<ref>{{cite book\n  | last = Audoin\n  | first = Claude\n  |author2=Bernard Guinot |author3=Stephen Lyle\n   | title = The Measurement of Time: Time, Frequency, and the Atomic Clock\n  | publisher = Cambridge Univ. Press\n  | year = 2001\n  | location = UK\n  | pages = 83\n  | url = https://books.google.com/books?id=LqdgUcm03A8C\n  | isbn = 0-521-00397-0}}</ref>  The home pendulum clock began to be replaced as domestic timekeeper during the 1930s and 1940s by the synchronous [[electric clock]], which kept more accurate time because it was synchronized to the oscillation of the [[electric power grid]]. {{anchor|Littlemore clock}}The most accurate experimental pendulum clock ever made<ref name="Kennedy">{{Cite news \n  | last = Kennedy\n  | first = Maev \n  | title = Scientist's historic clock collection for sale\n  | newspaper = The Guardian\n  | location = London\n  | publisher = Scott Trust Ltd.\n  | date = May 7, 2003\n  | url = https://www.theguardian.com/uk/2003/may/07/arts.science\n  | access-date = March 18, 2017}}</ref><ref name="Mumford">{{cite journal\n  | last1  = Mumford\n  | first1 = Bryan \n  | title = Some thoughts on the Littlemore clock\n  | journal = Horological Science Newsletter\n  | pages = 20\u201322\n  | publisher = National Assoc. of Watch and Clock Collectors\n  | date = November 2005\n  | url = http://www.cleyet.org/Pendula,%20Horological%20and%20Otherwise/The%20Littlemore%20clock%202.pdf\n  | access-date = March 18, 2017}}</ref> may be the Littlemore Clock built by [[Edward Thomas Hall|Edward T. Hall]] in the 1990s<ref>{{cite web\n|last=Hall\n|first=E.T.\n|title=The Littlemore Clock\n|date=June 1996\n|work=Horological Science\n|publisher=Nat'l Assoc. of Watch and Clock Collectors\n|pages=fig. 7b\n|url=http://www.hsn161.com/HSN/hsn_article.php}}</ref>\n(donated in 2003 to the [[National Watch and Clock Museum]], Columbia, Pennsylvania, USA)."}},
{"article_title": "Pauli effect", "pageid": "25018", "revid": "1043418856", "timestamp": "2021-09-10T01:21:55Z", "history_paths": [["Pauli effect --- Introduction ---", "Background"]], "categories": ["technology folklore", "experimental physics", "psychokinesis", "parapsychology"], "heading_tree": {"Pauli effect --- Introduction ---": {"Background": {}, "Anecdotal evidence": {}, "Cultural references": {}, "See also": {}, "Further reading": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Pauli effect --- Introduction ---|Background": "Since the 20th century, the work in some subfields of [[physics]] research has been divided between theorists and experimentalists. Those theorists who lack an aptitude or interest in experimental work have on occasion earned a reputation for accidentally breaking experimental equipment. Pauli was exceptional in this regard: it was postulated that he was such a good theorist that any experiments would be compromised by virtue of his presence in the vicinity. For fear of the Pauli effect, experimental physicist [[Otto Stern]] banned Pauli from his laboratory located in [[Hamburg]] despite their friendship.<ref>Enz (2009), p. 152.</ref> Pauli was convinced that the effect named after him was real.<ref name="Enz2002-150">Enz (2002), p. 150.</ref> He corresponded with [[Carl Jung]] and [[Marie-Louise von Franz]] about the concept of [[synchronicity]] and did so as well with [[Hans Bender]], lecturer at Freiburg university Institut f\u00fcr Grenzgebiete der Psychologie und Psychohygiene, the only [[parapsychology]] chair in Germany.<ref>Hans Bender und die Gr\u00fcndung des "Instituts f\u00fcr Grenzgebiete der Psychologie und Psychohygiene"Eberhard Bauer, September 1997. published in Jahnke, J., Fahrenberg, J., Stegie, R., & Bauer, E. (Hrsg.): Psychologiegeschichte: Beziehungen zu Philosophie und Grenzgebieten (Passauer Schriften zur Psychologiegeschichte; Bd. 12). M\u00fcnchen; Wien: Profil, 1998.</ref>\n\nJung and Pauli saw some parallels between physics and [[depth psychology]].<ref>Institut f\u00fcr Grenzgebiete der Psychologie und Psychohygiene, Bibliothek, Frei122-Z60 Zeitschrift f\u00fcr Parapsychologie und Grenzgebiete der Psychologie Band 4.1960/61, p.13</ref> Pauli was among the honored guests at the foundation festivities  of the [[C.G. Jung Institute]] in Z\u00fcrich 1948. A famous Pauli effect at the ceremony\u2014 as he entered, a china flower vase fell on the floor without any obvious reason\u2014caused Pauli to write his article "Background-Physics", in which he tries to find complementary relationships between physics and depth psychology.<ref name="meier2001-179">{{cite book |title=Atom and Archetype: the Pauli/Jung Letters, 1932-1958 |publisher=Princeton University Press |location=[[Princeton, New Jersey|Princeton]] |author1=Pauli, Wolfgang |author2=Jung, C G |author2-link=Carl Jung |others=ed. C.A. Meier |year=2001 |pages=179\u2013196 |isbn=0-691-01207-5 |oclc=45757717}}</ref>"}},
{"article_title": "Polish notation", "pageid": "25056", "revid": "1061596821", "timestamp": "2021-12-22T17:42:32Z", "history_paths": [["Polish notation --- Introduction ---", "History"]], "categories": ["mathematical notation", "polish inventions", "science and technology in poland", "operators (programming)", "logical expressions"], "heading_tree": {"Polish notation --- Introduction ---": {"History": {}, "Explanation": {}, "Evaluation algorithm": {}, "Polish notation for logic": {}, "Implementations": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Polish notation --- Introduction ---|History": "A quotation from a paper by [[Jan \u0141ukasiewicz]], ''Remarks on Nicod's Axiom and on "Generalizing Deduction"'', page 180, states how the notation was invented:\n<blockquote>I came upon the idea of a parenthesis-free notation in 1924. I used that notation for the first time in my article \u0141ukasiewicz(1), p. 610, footnote.</blockquote>\n\nThe reference cited by \u0141ukasiewicz is apparently a lithographed report in [[Polish language|Polish]]. The referring paper by \u0141ukasiewicz ''Remarks on Nicod's Axiom and on "Generalizing Deduction"'' was reviewed by [[Henry Pogorzelski|Henry A. Pogorzelski]] in the ''Journal of Symbolic Logic'' in 1965.<ref name="Pogorzelski_1965"/> [[Heinrich Behmann]], editor in 1924 of the article of [[Moses Sch\u00f6nfinkel]],<ref name="Mengelberg"/> already had the idea of eliminating parentheses in logic formulas.\n\n[[Alonzo Church]] mentions this notation in his classic book on [[mathematical logic]] as worthy of remark in notational systems even contrasted to [[Alfred North Whitehead|Alfred Whitehead]] and [[Bertrand Russell]]'s logical notational exposition and work in [[Principia Mathematica]].<ref name="Church_1944"/>\n\nIn \u0141ukasiewicz's 1951 book, ''Aristotle's Syllogistic from the Standpoint of Modern Formal Logic'', he mentions that the principle of his notation was to write the [[Function symbol|functor]]s before the [[Argument of a function|argument]]s to avoid brackets and that he had employed his notation in his logical papers since 1929.<ref name="\u0141ukasiewicz_1951"/> He then goes on to cite, as an example, a 1930 paper he wrote with [[Alfred Tarski]] on the [[Propositional calculus|sentential calculus]].<ref name="\u0141ukasiewicz_1930"/>\n\nWhile no longer used much in logic,<ref name="Mart\u00ednez_2011"/> Polish notation has since found a place in [[computer science]]."}},
{"article_title": "Quantum computing", "pageid": "25220", "revid": "1062976107", "timestamp": "2021-12-31T14:27:25Z", "history_paths": [["Quantum computing --- Introduction ---", "Developing physical quantum computers"]], "categories": ["quantum computing", "quantum information science", "models of computation", "quantum cryptography", "information theory", "computational complexity theory", "classes of computers", "theoretical computer science", "open problems", "computer-related introductions in 1980", "emerging technologies"], "heading_tree": {"Quantum computing --- Introduction ---": {"Quantum circuit": {"Definition": {}, "Quantum algorithms": {}}, "Potential applications": {"Cryptography": {}, "Search problems": {}, "Simulation of quantum systems": {}, "Quantum annealing and adiabatic optimization": {}, "Machine learning": {}, "Computational biology": {}, "Computer-aided drug design and generative chemistry": {}}, "Developing physical quantum computers": {"Challenges": {"Quantum decoherence": {}}, "Quantum supremacy": {}, "Skepticism": {}, "Candidates for physical realizations": {}}, "Relation to computability and complexity theory": {"Computability theory": {}, "Quantum complexity theory": {}}, "See also": {}, "References": {}, "Further reading": {"Textbooks": {}, "Academic papers": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Quantum computing --- Introduction ---|Developing physical quantum computers": "There are a number of technical challenges in building a large-scale quantum computer.<ref>{{cite journal |last=Dyakonov |first=Mikhail |url=https://spectrum.ieee.org/computing/hardware/the-case-against-quantum-computing |title=The Case Against Quantum Computing |journal=[[IEEE Spectrum]] |date=15 November 2018}}</ref> Physicist [[David P. DiVincenzo|David DiVincenzo]] has listed these [[DiVincenzo's criteria|requirements]] for a practical quantum computer:<ref>{{cite journal| arxiv=quant-ph/0002077|title=The Physical Implementation of Quantum Computation|last=DiVincenzo |first=David P.|date=13 April 2000|doi=10.1002/1521-3978(200009)48:9/11<771::AID-PROP771>3.0.CO;2-E|volume=48|issue=9\u201311|journal=Fortschritte der Physik|pages=771\u2013783|bibcode=2000ForPh..48..771D}}</ref>\n* Physically scalable to increase the number of qubits\n* Qubits that can be initialized to arbitrary values\n* Quantum gates that are faster than [[decoherence]] time\n* Universal gate set\n* Qubits that can be read easily\n\nSourcing parts for quantum computers is also very difficult. Many quantum computers, like those constructed by [[Google]] and [[IBM]], need [[helium-3]], a [[Nuclear physics|nuclear]] research byproduct, and special [[superconducting]] cables made only by the Japanese company Coax Co.<ref>{{cite news |last1=Giles |first1=Martin |title=We'd have more quantum computers if it weren't so hard to find the damn cables |url=https://www.technologyreview.com/s/612760/quantum-computers-component-shortage/ |publisher=MIT Technology Review |date=17 January 2019}}</ref>\n\nThe control of multi-qubit systems requires the generation and coordination of a large number of electrical signals with tight and deterministic timing resolution. This has led to the development of [[quantum controllers]] which enable interfacing with the qubits. Scaling these systems to support a growing number of qubits is an additional challenge.<ref>{{cite paper|authors=S. J. Pauka, K. Das, R. Kalra, A. Moini, Y. Yang, M. Trainer, A. Bousquet, C. Cantaloube, N. Dick, G. C. Gardner, M. J.|journal=[[Nature Electronics]]|title=A cryogenic CMOS chip for generating control signals for multiple qubits|year=2021|volume=4|issue=4|pages=64\u201370|doi=10.1038/s41928-020-00528-y|url=https://www.nature.com/articles/s41928-020-00528-y|arxiv=1912.01299|s2cid=231715555}}</ref>\n\n {{Main|Quantum decoherence}}\n\nOne of the greatest challenges involved with constructing quantum computers is controlling or removing [[quantum decoherence]]. This usually means isolating the system from its environment as interactions with the external world cause the system to decohere. However, other sources of decoherence also exist. Examples include the quantum gates, and the lattice vibrations and background thermonuclear spin of the physical system used to implement the qubits. Decoherence is irreversible, as it is effectively non-unitary, and is usually something that should be highly controlled, if not avoided. Decoherence times for candidate systems in particular, the transverse relaxation time ''T''<sub>2</sub> (for [[Nuclear magnetic resonance|NMR]] and [[MRI]] technology, also called the ''dephasing time''), typically range between nanoseconds and seconds at low temperature.<ref name="DiVincenzo 1995">{{cite journal |last=DiVincenzo |first=David P. |title=Quantum Computation |journal=Science |year=1995 |volume=270 |issue=5234 |pages=255\u2013261 |doi= 10.1126/science.270.5234.255 |bibcode = 1995Sci...270..255D |citeseerx=10.1.1.242.2165 |s2cid=220110562 }} {{subscription required}}</ref> Currently, some quantum computers require their qubits to be cooled to 20 millikelvin (usually using a [[dilution refrigerator]]<ref>{{Cite journal | doi = 10.1016/j.cryogenics.2021.103390| title = Development of Dilution refrigerators \u2013 A review | journal = Cryogenics| volume = 121| year = 2022| last1 = Zu | first1 = H.| last2 = Dai | first2 = W.| last3 = de Waele | first3 = A.T.A.M.| bibcode = 2022Cryo..121....1Z| s2cid = 244005391 }}</ref>) in order to prevent significant decoherence.<ref>{{cite journal|last1=Jones|first1=Nicola|title=Computing: The quantum company|journal=Nature|date=19 June 2013|volume=498|issue=7454|pages=286\u2013288|doi=10.1038/498286a|pmid=23783610|bibcode=2013Natur.498..286J|doi-access=free}}</ref> A 2020 study argues that [[ionizing radiation]] such as [[cosmic rays]] can nevertheless cause certain systems to decohere within milliseconds.<ref>{{cite journal |last1=Veps\u00e4l\u00e4inen |first1=Antti P. |last2=Karamlou |first2=Amir H. |last3=Orrell |first3=John L. |last4=Dogra |first4=Akshunna S. |last5=Loer |first5=Ben |last6=Vasconcelos |first6=Francisca |last7=Kim |first7=David K. |last8=Melville |first8=Alexander J. |last9=Niedzielski |first9=Bethany M. |last10=Yoder |first10=Jonilyn L. |last11=Gustavsson |first11=Simon |last12=Formaggio |first12=Joseph A. |last13=VanDevender |first13=Brent A. |last14=Oliver |first14=William D. |display-authors=5 |title=Impact of ionizing radiation on superconducting qubit coherence |journal=Nature |date=August 2020 |volume=584 |issue=7822 |pages=551\u2013556 |doi=10.1038/s41586-020-2619-8 |pmid=32848227 |url=https://www.nature.com/articles/s41586-020-2619-8 |language=en |issn=1476-4687|arxiv=2001.09190 |bibcode=2020Natur.584..551V |s2cid=210920566 }}</ref>\n\nAs a result, time-consuming tasks may render some quantum algorithms inoperable, as maintaining the state of qubits for a long enough duration will eventually corrupt the superpositions.<ref>{{cite arxiv|last1=Amy|first1=Matthew|last2=Matteo|first2=Olivia|last3=Gheorghiu|first3=Vlad|last4=Mosca|first4=Michele|last5=Parent|first5=Alex|last6=Schanck|first6=John|title=Estimating the cost of generic quantum pre-image attacks on SHA-2 and SHA-3|date=30 November 2016|eprint=1603.09383|class=quant-ph}}</ref>\n\nThese issues are more difficult for optical approaches as the timescales are orders of magnitude shorter and an often-cited approach to overcoming them is optical [[pulse shaping]]. Error rates are typically proportional to the ratio of operating time to decoherence time, hence any operation must be completed much more quickly than the decoherence time.\n\nAs described in the [[Quantum threshold theorem]], if the error rate is small enough, it is thought to be possible to use [[quantum error correction]] to suppress errors and decoherence. This allows the total calculation time to be longer than the decoherence time if the error correction scheme can correct errors faster than decoherence introduces them. An often cited figure for the required error rate in each gate for fault-tolerant computation is 10<sup>\u22123</sup>, assuming the noise is depolarizing.\n\nMeeting this scalability condition is possible for a wide range of systems. However, the use of error correction brings with it the cost of a greatly increased number of required qubits. The number required to factor integers using Shor's algorithm is still polynomial, and thought to be between ''L'' and ''L''<sup>2</sup>, where ''L'' is the number of digits in the number to be factored; error correction algorithms would inflate this figure by an additional factor of ''L''. For a 1000-bit number, this implies a need for about 10<sup>4</sup> bits without error correction.<ref>{{cite journal |title=Is Fault-Tolerant Quantum Computation Really Possible? |last=Dyakonov |first=M. I. |date=14 October 2006 |pages=4\u201318 |journal=Future Trends in Microelectronics. Up the Nano Creek |editor1=S. Luryi |editor2=J. Xu |editor3=A. Zaslavsky | arxiv=quant-ph/0610117|bibcode=2006quant.ph.10117D }}</ref> With error correction, the figure would rise to about 10<sup>7</sup> bits. Computation time is about ''L''<sup>2</sup> or about 10<sup>7</sup> steps and at 1 MHz, about 10 seconds.\n\nA very different approach to the stability-decoherence problem is to create a [[topological quantum computer]] with [[anyon]]s, [[quasi-particle]]s used as threads and relying on [[braid theory]] to form stable logic gates.<ref>{{cite journal\n | last1 = Freedman | first1 = Michael H. | author1-link = Michael Freedman\n | last2 = Kitaev | first2 = Alexei | author2-link = Alexei Kitaev\n | last3 = Larsen | first3 = Michael J. | author3-link = Michael J. Larsen\n | last4 = Wang | first4 = Zhenghan\n | arxiv = quant-ph/0101025\n | doi = 10.1090/S0273-0979-02-00964-3\n | issue = 1\n | journal = Bulletin of the American Mathematical Society\n | mr = 1943131\n | pages = 31\u201338\n | title = Topological quantum computation\n | volume = 40\n | year = 2003}}</ref><ref>{{cite journal |last=Monroe |first=Don |url=https://www.newscientist.com/channel/fundamentals/mg20026761.700-anyons-the-breakthrough-quantum-computing-needs.html |title=Anyons: The breakthrough quantum computing needs? |journal=[[New Scientist]] |date=1 October 2008}}</ref>\n\n {{Main|Quantum supremacy}}\n''[[Quantum supremacy]]'' is a term coined by [[John Preskill]] referring to the engineering feat of demonstrating that a programmable quantum device can solve a problem beyond the capabilities of state-of-the-art classical computers.<ref>{{cite arxiv |last=Preskill |first=John |date=2012-03-26 |title=Quantum computing and the entanglement frontier |eprint=1203.5813 |class=quant-ph}}</ref><ref>{{Cite journal|last=Preskill|first=John|date=2018-08-06|title=Quantum Computing in the NISQ era and beyond|journal=Quantum|volume=2|pages=79|doi=10.22331/q-2018-08-06-79|doi-access=free}}</ref><ref>{{Cite journal|title=Characterizing Quantum Supremacy in Near-Term Devices|journal=Nature Physics|volume=14|issue=6|pages=595\u2013600|first1=Sergio|last1=Boixo|first2=Sergei V.|last2=Isakov|first3=Vadim N.|last3=Smelyanskiy|first4=Ryan|last4=Babbush|first5=Nan|last5=Ding|first6=Zhang|last6=Jiang|first7=Michael J.|last7=Bremner|first8=John M.|last8=Martinis|first9=Hartmut|last9=Neven|year=2018|arxiv=1608.00263|doi=10.1038/s41567-018-0124-x|bibcode=2018NatPh..14..595B|s2cid=4167494}}</ref> The problem need not be useful, so some view the quantum supremacy test only as a potential future benchmark.<ref>{{cite web|url=https://www.scientificamerican.com/article/quantum-computers-compete-for-supremacy/|title=Quantum Computers Compete for "Supremacy"|first=Neil|last=Savage|work=Scientific American|date=5 July 2017}}</ref>\n\nIn October 2019, Google AI Quantum, with the help of NASA, became the first to claim to have achieved quantum supremacy by performing calculations on the [[Sycamore processor|Sycamore quantum computer]] more than 3,000,000 times faster than they could be done on [[Summit (supercomputer)|Summit]], generally considered the world's fastest computer.<ref>{{cite journal|last1=Arute|first1=Frank|last2=Arya|first2=Kunal|last3=Babbush|first3=Ryan|last4=Bacon|first4=Dave|last5=Bardin|first5=Joseph C.|last6=Barends|first6=Rami|last7=Biswas|first7=Rupak|last8=Boixo|first8=Sergio|last9=Brandao|first9=Fernando G. S. L.|last10=Buell|first10=David A.|last11=Burkett|first11=Brian|date=23 October 2019|title=Quantum supremacy using a programmable superconducting processor|journal=Nature|volume=574|issue=7779|first15=Roberto|first57=Murphy Yuezhen|last64=Rubin|first63=Pedram|last63=Roushan|first62=Eleanor G.|last62=Rieffel|first61=Chris|last61=Quintana|first60=John C.|last60=Platt|first59=Andre|last59=Petukhov|first58=Eric|last58=Ostby|last57=Niu|last65=Sank|first56=Charles|last56=Neill|first55=Matthew|last55=Neeley|first54=Ofer|last54=Naaman|first53=Josh|last53=Mutus|first52=Masoud|last52=Mohseni|first51=Kristel|last51=Michielsen|first50=Xiao|last50=Mi|first64=Nicholas C.|first65=Daniel|last49=Megrant|last74=Yeh|last12=Chen|first12=Yu|last13=Chen|first13=Zijun|last14=Chiaro|first14=Ben|first77=John M.|last77=Martinis|first76=Hartmut|last76=Neven|first75=Adam|last75=Zalcman|first74=Ping|first73=Z. Jamie|last66=Satzinger|last73=Yao|first72=Theodore|last72=White|first71=Benjamin|last71=Villalonga|first70=Amit|last70=Vainsencher|first69=Matthew D.|last69=Trevithick|first68=Kevin J.|last68=Sung|first67=Vadim|last67=Smelyanskiy|first66=Kevin J.|first49=Anthony|first48=Matthew|last16=Courtney|last24=Guerin|first30=Trent|last30=Huang|first29=Markus|last29=Hoffman|first28=Alan|last28=Ho|first27=Michael J.|last27=Hartmann|first26=Matthew P.|last26=Harrigan|first25=Steve|last25=Habegger|first24=Keith|first23=Rob|first31=Travis S.|last23=Graff|first22=Marissa|last22=Giustina|first21=Craig|last21=Gidney|first20=Austin|last20=Fowler|first19=Brooks|last19=Foxen|first18=Edward|last18=Farhi|first17=Andrew|last17=Dunsworsth|first16=William|last31=Humble|last32=Isakov|last48=McEwen|first40=Alexander|first47=Jarrod R.|last47=McClean|first46=Salvatore|last46=Mandr\u00e0|first45=Dmitry|last45=Lyakh|first44=Erik|last44=Lucero|first43=Mike|last43=Lindmark|first42=David|last42=Landhuis|first41=Fedor|last15=Collins|last40=Korotov|first32=Sergei V.|first39=Sergey|last39=Knysh|first38=Paul V.|last38=Klimov|first37=Julian|last37=Kelly|first36=Kostyantyn|last36=Kechedzhi|first35=Dvir|last35=Kafri|first34=Zhang|last34=Jiang|first33=Evan|last33=Jeffery|last41=Kostritsa|doi=10.1038/s41586-019-1666-5|pmid=31645734|pages=505\u2013510|bibcode=2019Natur.574..505A|arxiv=1910.11333|s2cid=204836822}}</ref><ref>{{cite web|url=https://www.technologyreview.com/f/614416/google-researchers-have-reportedly-achieved-quantum-supremacy/|title=Google researchers have reportedly achieved 'quantum supremacy'|website=MIT Technology Review}}</ref><ref>{{Cite web|last=Tavares|first=Frank|date=2019-10-23|title=Google and NASA Achieve Quantum Supremacy|url=http://www.nasa.gov/feature/ames/quantum-supremacy|access-date=2021-11-16|website=NASA}}</ref> This claim has been subsequently challenged: IBM has stated that Summit can perform samples much faster than claimed,<ref>{{cite arxiv|last1=Pednault|first1=Edwin|last2=Gunnels|first2=John A.|last3=Nannicini|first3=Giacomo|last4=Horesh|first4=Lior|last5=Wisnieff|first5=Robert|date=2019-10-22|title=Leveraging Secondary Storage to Simulate Deep 54-qubit Sycamore Circuits|class=quant-ph|eprint=1910.09534}}</ref><ref>{{Cite journal|last=Cho|first=Adrian|date=2019-10-23|title=IBM casts doubt on Google's claims of quantum supremacy|url=https://www.sciencemag.org/news/2019/10/ibm-casts-doubt-googles-claims-quantum-supremacy|journal=Science|doi=10.1126/science.aaz6080|s2cid=211982610|issn=0036-8075}}</ref> and researchers have since developed better algorithms for the sampling problem used to claim quantum supremacy, giving substantial reductions to or the closing of the gap between Sycamore and classical supercomputers.<ref>{{Cite journal|last1=Liu|first1=Yong (Alexander)|last2=Liu|first2=Xin (Lucy)|last3=Li|first3=Fang (Nancy)|last4=Fu|first4=Haohuan|last5=Yang|first5=Yuling|last6=Song|first6=Jiawei|last7=Zhao|first7=Pengpeng|last8=Wang|first8=Zhen|last9=Peng|first9=Dajia|last10=Chen|first10=Huarong|last11=Guo|first11=Chu|date=2021-11-14|title=Closing the "quantum supremacy" gap: achieving real-time simulation of a random quantum circuit using a new Sunway supercomputer|url=https://doi.org/10.1145/3458817.3487399|journal=Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis|series=SC '21|location=New York, NY, USA|publisher=Association for Computing Machinery|pages=1\u201312|doi=10.1145/3458817.3487399|arxiv=2110.14502|isbn=978-1-4503-8442-1|s2cid=239036985}}</ref><ref>{{cite arxiv|last1=Pan|first1=Feng|last2=Chen|first2=Keyang|last3=Zhang|first3=Pan|date=2021-11-04|title=Solving the sampling problem of the Sycamore quantum supremacy circuits|class=quant-ph|eprint=2111.03011}}</ref>\n\nIn December 2020, a group at [[University of Science and Technology of China|USTC]] implemented a type of [[Boson sampling]] on 76 photons with a [[Linear optical quantum computing|photonic quantum computer]] [[Jiuzhang (quantum computer)|Jiuzhang]] to demonstrate quantum supremacy.<ref>{{Cite journal|last=Ball|first=Philip|date=2020-12-03|title=Physicists in China challenge Google's 'quantum advantage'|journal=Nature|volume=588|issue=7838|page=380|language=en|doi=10.1038/d41586-020-03434-7|pmid=33273711|bibcode=2020Natur.588..380B|doi-access=free}}</ref><ref>{{Cite web|last=Garisto|first=Daniel|title=Light-based Quantum Computer Exceeds Fastest Classical Supercomputers|url=https://www.scientificamerican.com/article/light-based-quantum-computer-exceeds-fastest-classical-supercomputers/|access-date=2020-12-07|website=Scientific American|language=en}}</ref><ref>{{Cite web|last=Conover|first=Emily|date=2020-12-03|title=The new light-based quantum computer Jiuzhang has achieved quantum supremacy|url=https://www.sciencenews.org/article/new-light-based-quantum-computer-jiuzhang-supremacy|access-date=2020-12-07|website=Science News|language=en-US}}</ref> The authors claim that a classical contemporary supercomputer would require a computational time of 600 million years to generate the number of samples their quantum processor can generate in 20 seconds.<ref name=":6">{{Cite journal|last1=Zhong|first1=Han-Sen|last2=Wang|first2=Hui|last3=Deng|first3=Yu-Hao|last4=Chen|first4=Ming-Cheng|last5=Peng|first5=Li-Chao|last6=Luo|first6=Yi-Han|last7=Qin|first7=Jian|last8=Wu|first8=Dian|last9=Ding|first9=Xing|last10=Hu|first10=Yi|last11=Hu|first11=Peng|date=2020-12-03|title=Quantum computational advantage using photons|url=https://science.sciencemag.org/content/early/2020/12/02/science.abe8770|journal=Science|volume=370|issue=6523|pages=1460\u20131463|language=en|doi=10.1126/science.abe8770|issn=0036-8075|pmid=33273064|arxiv=2012.01625|bibcode=2020Sci...370.1460Z|s2cid=227254333}}</ref>\nOn November 16, 2021 at the quantum computing summit IBM presented a 127-qubit microprocessor named [[IBM Eagle]].<ref>{{Cite web|date=2021-11-15|title=IBM's Eagle -- 127-Qubit Quantum Processor -- Takes Flight|url=https://thequantumdaily.com/2021/11/15/ibms-eagle-127-qubit-quantum-processor-takes-flight-another-step-toward-frictionless-quantum-in-2025/|access-date=2021-11-18|website=The Quantum Daily|language=en-US}}</ref>\n\n \nSome researchers have expressed skepticism that scalable quantum computers could ever be built, typically because of the issue of maintaining coherence at large scales.\n\n[[Bill Unruh]] doubted the practicality of quantum computers in a paper published back in 1994.<ref>{{Cite journal|last1=Unruh|first1=Bill|title=Maintaining coherence in Quantum Computers|journal=Physical Review A|volume=51|issue=2|pages=992\u2013997|arxiv=hep-th/9406058|bibcode=1995PhRvA..51..992U|year=1995|doi=10.1103/PhysRevA.51.992|pmid=9911677|s2cid=13980886}}</ref> [[Paul Davies]] argued that a 400-qubit computer would even come into conflict with the cosmological information bound implied by the [[holographic principle]].<ref>{{cite web|last1=Davies|first1=Paul|title=The implications of a holographic universe for quantum information science and the nature of physical law|url=https://arxiv.org/ftp/quant-ph/papers/0703/0703041.pdf|publisher=Macquarie University}}</ref> Skeptics like [[Gil Kalai]] doubt that quantum supremacy will ever be achieved.<ref>{{cite web|url=https://rjlipton.wordpress.com/2016/04/22/quantum-supremacy-and-complexity/|title=Quantum Supremacy and Complexity|date=23 April 2016}}</ref><ref>{{cite web|last1=Kalai|first1=Gil|title=The Quantum Computer Puzzle|url=https://www.ams.org/journals/notices/201605/rnoti-p508.pdf|publisher=AMS}}</ref><ref>{{cite arxiv|last1=Rinott|first1=Yosef|last2=Shoham|first2=Tomer|last3=Kalai|first3=Gil|date=2021-07-13|title=Statistical Aspects of the Quantum Supremacy Demonstration|class=quant-ph|eprint=2008.05177}}</ref> Physicist [[Mikhail Dyakonov]] has expressed skepticism of quantum computing as follows:\n:"So the number of continuous parameters describing the state of such a useful quantum computer at any given moment must be... about 10<sup>300</sup>... Could we ever learn to control the more than 10<sup>300</sup> continuously variable parameters defining the quantum state of such a system? My answer is simple. ''No, never.''"<ref>{{cite web |last1=Dyakonov |first1=Mikhail |title=The Case Against Quantum Computing |url=https://spectrum.ieee.org/computing/hardware/the-case-against-quantum-computing |website=IEEE Spectrum |date=15 November 2018 |access-date=3 December 2019}}</ref><ref>{{cite book |last1=Dyakonov |first1=Mikhail |title=Will We Ever Have a Quantum Computer? |date=24 March 2020 |url=https://www.springer.com/gp/book/9783030420185 |publisher=Springer |isbn=9783030420185 |access-date=22 May 2020}}{{page needed|date=May 2020}}</ref>\n\n For physically implementing a quantum computer, many different candidates are being pursued, among them (distinguished by the physical system used to realize the qubits):\n\n*[[Superconducting quantum computing]]<ref name="ClarkeWilhelm2008">{{cite journal |last1=Clarke |first1=John |last2=Wilhelm |first2=Frank K. |title=Superconducting quantum bits |journal=Nature |date=18 June 2008 |volume=453 |issue=7198 |pages=1031\u20131042 |doi=10.1038/nature07128 |pmid=18563154 |bibcode=2008Natur.453.1031C |s2cid=125213662 |url=https://www.semanticscholar.org/paper/7ee1053ce63f33a62f2ea555547c514ce5f21054 }}</ref><ref>{{cite journal |last1=Kaminsky |first1=William M. |last2=Lloyd |first2=Seth |last3=Orlando |first3=Terry P. |title=Scalable Superconducting Architecture for Adiabatic Quantum Computation |arxiv=quant-ph/0403090 |date=12 March 2004 |bibcode=2004quant.ph..3090K }}</ref> (qubit implemented by the state of small superconducting circuits [<nowiki/>[[Josephson junctions]]])\n*[[Trapped ion quantum computer]] (qubit implemented by the internal state of trapped ions)\n*Neutral atoms in [[optical lattice]]s (qubit implemented by internal states of neutral atoms trapped in an optical lattice)<ref>{{Cite journal|last1=Khazali|first1=Mohammadsadegh|last2=M\u00f8lmer|first2=Klaus|date=11 June 2020|title=Fast Multiqubit Gates by Adiabatic Evolution in Interacting Excited-State Manifolds of Rydberg Atoms and Superconducting Circuits|journal=Physical Review X|volume=10|issue=2|page=021054|doi=10.1103/PhysRevX.10.021054|bibcode=2020PhRvX..10b1054K|doi-access=free}}</ref><ref>{{Cite journal|last1=Henriet|first1=Loic|last2=Beguin|first2=Lucas|last3=Signoles|first3=Adrien|last4=Lahaye|first4=Thierry|last5=Browaeys|first5=Antoine|last6=Reymond|first6=Georges-Olivier|last7=Jurczak|first7=Christophe|date=22 June 2020|title=Quantum computing with neutral atoms|journal=Quantum|volume=4|page=327|doi=10.22331/q-2020-09-21-327|arxiv=2006.12326|s2cid=219966169}}</ref>\n*[[Quantum dot]] computer, spin-based (e.g. the [[Loss-DiVincenzo quantum computer]]<ref>{{cite journal |last1=Imamog\u00aflu |first1=A. |last2=Awschalom |first2=D. D. |last3=Burkard |first3=G. |last4=DiVincenzo |first4=D. P. |last5=Loss |first5=D. |last6=Sherwin |first6=M. |last7=Small |first7=A. |title=Quantum Information Processing Using Quantum Dot Spins and Cavity QED |journal=Physical Review Letters |date=15 November 1999 |volume=83 |issue=20 |pages=4204\u20134207 |doi=10.1103/PhysRevLett.83.4204 |bibcode=1999PhRvL..83.4204I |arxiv=quant-ph/9904096 |s2cid=18324734 }}</ref>) (qubit given by the spin states of trapped electrons)\n*Quantum dot computer, spatial-based (qubit given by electron position in double quantum dot)<ref>{{cite journal |last1=Fedichkin |first1=L. |last2=Yanchenko |first2=M. |last3=Valiev |first3=K. A. |title=Novel coherent quantum bit using spatial quantization levels in semiconductor quantum dot |journal=Quantum Computers and Computing |date=June 2000 |volume=1 |page=58 |bibcode=2000quant.ph..6097F |arxiv=quant-ph/0006097 }}</ref>\n* Quantum computing using engineered quantum wells, which could in principle enable the construction of quantum computers that operate at room temperature<ref>{{cite journal |last1=Iv\u00e1dy |first1=Viktor |last2=Davidsson |first2=Joel |last3=Delegan |first3=Nazar |last4=Falk |first4=Abram L. |last5=Klimov |first5=Paul V. |last6=Whiteley |first6=Samuel J. |last7=Hruszkewycz |first7=Stephan O. |last8=Holt |first8=Martin V. |last9=Heremans |first9=F. Joseph |last10=Son |first10=Nguyen Tien |last11=Awschalom |first11=David D. |last12=Abrikosov |first12=Igor A. |last13=Gali |first13=Adam |title=Stabilization of point-defect spin qubits by quantum wells |journal=Nature Communications |date=6 December 2019 |volume=10 |issue=1 |page=5607 |doi=10.1038/s41467-019-13495-6 |pmid=31811137 |pmc=6898666 |arxiv=1905.11801 |bibcode=2019NatCo..10.5607I }}</ref><ref>{{cite news |title=Scientists Discover New Way to Get Quantum Computing to Work at Room Temperature |url=https://interestingengineering.com/scientists-discover-new-way-to-get-quantum-computing-to-work-at-room-temperature |work=interestingengineering.com |date=24 April 2020 }}</ref>\n*Coupled [[quantum wire]] (qubit implemented by a pair of quantum wires coupled by a [[quantum point contact]])<ref>{{cite journal |last1=Bertoni |first1=A. |last2=Bordone |first2=P. |last3=Brunetti |first3=R. |last4=Jacoboni |first4=C. |last5=Reggiani |first5=S. |title=Quantum Logic Gates based on Coherent Electron Transport in Quantum Wires |journal=Physical Review Letters |date=19 June 2000 |volume=84 |issue=25 |pages=5912\u20135915 |doi=10.1103/PhysRevLett.84.5912 |pmid=10991086 |bibcode=2000PhRvL..84.5912B |hdl=11380/303796|hdl-access=free }}</ref><ref>{{cite journal |last1=Ionicioiu |first1=Radu |last2=Amaratunga |first2=Gehan |last3=Udrea |first3=Florin |title=Quantum Computation with Ballistic Electrons |journal=International Journal of Modern Physics B |date=20 January 2001 |volume=15 |issue=2 |pages=125\u2013133 |doi=10.1142/S0217979201003521 |arxiv=quant-ph/0011051 |bibcode=2001IJMPB..15..125I |citeseerx=10.1.1.251.9617 |s2cid=119389613 }}</ref><ref>{{cite journal |last1=Ramamoorthy |first1=A |last2=Bird |first2=J P |last3=Reno |first3=J L |title=Using split-gate structures to explore the implementation of a coupled-electron-waveguide qubit scheme |journal=Journal of Physics: Condensed Matter |date=11 July 2007 |volume=19 |issue=27 |page=276205 |doi=10.1088/0953-8984/19/27/276205 |bibcode=2007JPCM...19A6205R }}</ref>\n*[[Nuclear magnetic resonance quantum computer]] (NMRQC) implemented with the [[nuclear magnetic resonance]] of molecules in solution, where qubits are provided by [[nuclear spin]]s within the dissolved molecule and probed with radio waves\n*Solid-state NMR [[Kane quantum computer]]s (qubit realized by the nuclear spin state of [[phosphorus]] [[Electron donor|donors]] in [[silicon]])\n*[[Electron-on-Helium Qubit|Electrons-on-helium quantum computers]] (qubit is the electron spin)\n*[[Cavity quantum electrodynamics]] (CQED) (qubit provided by the internal state of trapped atoms coupled to high-finesse cavities)\n*[[Single-molecule magnet|Molecular magnet]]<ref>{{cite journal |last1=Leuenberger |first1=Michael N. |last2=Loss |first2=Daniel |title=Quantum computing in molecular magnets |journal=Nature |date=April 2001 |volume=410 |issue=6830 |pages=789\u2013793 |doi=10.1038/35071024 |pmid=11298441 |arxiv=cond-mat/0011415 |bibcode=2001Natur.410..789L |s2cid=4373008 }}</ref> (qubit given by spin states)\n*[[Fullerene]]-based [[Electron paramagnetic resonance|ESR]] quantum computer (qubit based on the electronic spin of [[Endohedral fullerene|atoms or molecules encased in fullerenes]])<ref>{{cite journal |last1=Harneit |first1=Wolfgang |title=Fullerene-based electron-spin quantum computer |journal= Physical Review A|date=27 February 2002 |volume=65 |issue=3 |page=032322 |doi=10.1103/PhysRevA.65.032322 |bibcode=2002PhRvA..65c2322H |url=https://www.researchgate.net/publication/257976907}}</ref>\n*[[Optical quantum computing|Nonlinear optical quantum computer]] (qubits realized by processing states of different [[Normal mode|modes]] of light through both linear and [[Nonlinear optics|nonlinear]] elements)<ref name="qc1988">{{cite conference |first1=K. |last1=Igeta |first2=Y. |last2=Yamamoto |title=Quantum mechanical computers with single atom and photon fields |conference=International Quantum Electronics Conference |year=1988 |url=https://www.osapublishing.org/abstract.cfm?uri=IQEC-1988-TuI4}}</ref><ref name="chuang1995">{{cite journal |first1=I.L. |last1=Chuang |first2=Y. |last2=Yamamoto |title=Simple quantum computer |journal=Physical Review A |volume=52 |issue=5 |year=1995 |pages=3489\u20133496 |doi=10.1103/PhysRevA.52.3489|pmid=9912648 |arxiv=quant-ph/9505011 |bibcode=1995PhRvA..52.3489C |s2cid=30735516 }}</ref>\n*[[Linear optical quantum computing|Linear optical quantum computer]] (qubits realized by processing states of different [[Normal mode|modes]] of light through linear elements e.g. mirrors, [[beam splitter]]s and [[phase shift module|phase shifters]])<ref name="KLM2001">{{cite journal |last1=Knill |first1=G. J. |last2=Laflamme |last3=Milburn |title=A scheme for efficient quantum computation with linear optics |journal=Nature |year=2001 |volume=409 |doi=10.1038/35051009 |bibcode = 2001Natur.409...46K |first2=R. |first3=G. J. |issue=6816 |pmid=11343107 |pages=46\u201352 |s2cid=4362012 |url=https://www.semanticscholar.org/paper/054b680165a7325569ca6e63028ca9cee7f3ac9a }}</ref>\n*[[Diamond-based quantum computer]]<ref name="Nizovtsevetal2004">{{cite journal\n|journal = Optics and Spectroscopy\n|date = August 2005\n|title = A quantum computer based on NV centers in diamond: Optically detected nutations of single electron and nuclear spins\n|author = Nizovtsev, A. P.\n|volume = 99 |issue = 2\n|pages = 248\u2013260\n|doi = 10.1134/1.2034610\n|bibcode = 2005OptSp..99..233N |s2cid = 122596827\n|url = https://www.semanticscholar.org/paper/a7598ca24265e5537f14dc61b7c3a1d5b5953162\n}}</ref><ref>{{cite journal |last1=Dutt |first1=M. V. G. |last2=Childress |first2=L. |last3=Jiang |first3=L. |last4=Togan |first4=E. |last5=Maze |first5=J. |last6=Jelezko |first6=F. |last7=Zibrov |first7=A. S. |last8=Hemmer |first8=P. R. |last9=Lukin |first9=M. D. |title=Quantum Register Based on Individual Electronic and Nuclear Spin Qubits in Diamond |journal=Science |date=1 June 2007 |volume=316 |issue=5829 |pages=1312\u20131316 |doi=10.1126/science.1139831 |pmid=17540898 |lay-url=https://news.harvard.edu/gazette/story/2007/06/single-spinning-nuclei-in-diamond-offer-a-stable-quantum-computing-building-block/ |bibcode=2007Sci...316.....D |s2cid=20697722 }}</ref><ref name="Neumannetal2008">{{cite journal\n|journal = Science\n|date = 6 June 2008\n|title = Multipartite Entanglement Among Single Spins in Diamond\n|author = Neumann, P.\n|volume = 320\n|issue = 5881\n|pages = 1326\u20131329\n|doi = 10.1126/science.1157233\n|pmid = 18535240\n|bibcode = 2008Sci...320.1326N\n|display-authors = 1\n|last2 = Mizuochi\n|first2 = N.\n|last3 = Rempp\n|first3 = F.\n|last4 = Hemmer\n|first4 = P.\n|last5 = Watanabe\n|first5 = H.\n|last6 = Yamasaki\n|first6 = S.\n|last7 = Jacques\n|first7 = V.\n|last8 = Gaebel\n|first8 = T.\n|last9 = Jelezko\n|first9 = F. |s2cid = 8892596\n}}</ref> (qubit realized by the electronic or nuclear spin of [[nitrogen-vacancy center]]s in diamond)\n*[[Bose\u2013Einstein condensate|Bose-Einstein condensate]]-based quantum computer<ref>{{cite journal |last1=Anderlini |first1=Marco |last2=Lee |first2=Patricia J. |last3=Brown |first3=Benjamin L. |last4=Sebby-Strabley |first4=Jennifer |last5=Phillips |first5=William D. |last6=Porto |first6=J. V. |title=Controlled exchange interaction between pairs of neutral atoms in an optical lattice |journal=Nature |date=July 2007 |volume=448 |issue=7152 |pages=452\u2013456 |doi=10.1038/nature06011 |pmid=17653187 |lay-url=https://www.nist.gov/news-events/news/2007/07/thousands-atoms-swap-spins-partners-quantum-square-dance |arxiv=0708.2073 |bibcode=2007Natur.448..452A |s2cid=4410355 }}</ref>\n*Transistor-based quantum computer \u2013 string quantum computers with entrainment of positive holes using an electrostatic trap\n*Rare-earth-metal-ion-doped inorganic crystal based quantum computers<ref name="Ohlsson2002">{{cite journal\n|journal = Opt. Commun.\n|date = 1 January 2002\n|title = Quantum computer hardware based on rare-earth-ion-doped inorganic crystals\n|first1 = N.\n|last1 = Ohlsson\n|first2 = R. K.\n|last2 = Mohan\n|first3 = S.\n|last3 = Kr\u00f6ll\n|volume = 201\n|issue = 1\u20133\n|pages = 71\u201377\n|doi = 10.1016/S0030-4018(01)01666-2\n|bibcode = 2002OptCo.201...71O }}</ref><ref name="Longdell2004">{{cite journal\n|journal = Phys. Rev. Lett.\n|date = 23 September 2004\n|title = Demonstration of conditional quantum phase shift between ions in a solid\n|first1 = J. J.\n|last1 = Longdell\n|first2 = M. J.\n|last2 = Sellars\n|first3 = N. B.\n|last3 = Manson\n|volume = 93\n|issue = 13\n|page = 130503\n|doi = 10.1103/PhysRevLett.93.130503\n|pmid = 15524694\n|arxiv = quant-ph/0404083 |bibcode = 2004PhRvL..93m0503L |s2cid = 41374015\n}}</ref> (qubit realized by the internal electronic state of [[dopant]]s in [[optical fiber]]s)\n*Metallic-like carbon nanospheres-based quantum computers<ref name="Nafradi2016">{{cite journal |last1=N\u00e1fr\u00e1di |first1=B\u00e1lint |last2=Choucair |first2=Mohammad |last3=Dinse |first3=Klaus-Peter |last4=Forr\u00f3 |first4=L\u00e1szl\u00f3 |title=Room temperature manipulation of long lifetime spins in metallic-like carbon nanospheres |journal=Nature Communications |date=18 July 2016 |volume=7 |issue=1 |page=12232 |doi=10.1038/ncomms12232 |pmid=27426851 |pmc=4960311 |arxiv=1611.07690 |bibcode=2016NatCo...712232N }}</ref>\n\nThe large number of candidates demonstrates that quantum computing, despite rapid progress, is still in its infancy.{{citation needed|date=May 2020}}\n\nThere are a number of quantum computing models, distinguished by the basic elements in which the computation is decomposed. For practical implementations, the four relevant models of computation are:\n* [[quantum circuit|Quantum gate array]] (computation decomposed into a sequence of few-qubit [[quantum gate]]s)\n* [[One-way quantum computer]] (computation decomposed into a sequence of one-qubit measurements applied to a highly entangled initial state or [[cluster state]])\n* [[Adiabatic quantum computation|Adiabatic quantum computer]], based on [[quantum annealing]] (computation decomposed into a slow continuous transformation of an initial [[Hamiltonian (quantum mechanics)|Hamiltonian]] into a final Hamiltonian, whose ground states contain the solution)<ref name="Das 2008 1061\u20131081">{{cite journal|last1=Das|first1=A.|last2=Chakrabarti|first2=B. K.|year=2008|title=Quantum Annealing and Analog Quantum Computation|journal=[[Reviews of Modern Physics|Rev. Mod. Phys.]]|volume=80|issue=3|pages=1061\u20131081|arxiv=0801.2193|bibcode=2008RvMP...80.1061D|citeseerx=10.1.1.563.9990|doi=10.1103/RevModPhys.80.1061|s2cid=14255125}}</ref>\n* [[Topological quantum computer]]<ref name="Nayaketal2008">{{cite journal|last1=Nayak|first1=Chetan|last2=Simon|first2=Steven|last3=Stern|first3=Ady|last4=Das Sarma|first4=Sankar|year=2008|title=Nonabelian Anyons and Quantum Computation|journal=Reviews of Modern Physics|volume=80|issue=3|pages=1083\u20131159|arxiv=0707.1889|bibcode=2008RvMP...80.1083N|doi=10.1103/RevModPhys.80.1083|s2cid=119628297}}</ref> (computation decomposed into the braiding of [[anyon]]s in a 2D lattice)\nThe [[quantum Turing machine]] is theoretically important but the physical implementation of this model is not feasible. All four models of computation have been shown to be equivalent; each can simulate the other with no more than polynomial overhead."}},
{"article_title": "Quantum teleportation", "pageid": "25280", "revid": "1059027835", "timestamp": "2021-12-07T00:44:20Z", "history_paths": [["Quantum teleportation --- Introduction ---", "Experimental results and records"]], "categories": ["quantum information science", "quantum computing", "emerging technologies", "teleportation"], "heading_tree": {"Quantum teleportation --- Introduction ---": {"Non-technical summary": {}, "Protocol": {}, "Experimental results and records": {"Quantum teleportation over 143 km": {}, "Quantum teleportation across the Danube River": {}, "Deterministic quantum teleportation with atoms": {}, "Ground-to-satellite quantum teleportation": {}}, "Formal presentation": {}, "Alternative notations": {}, "Entanglement swapping": {"Algorithm for swapping Bell pairs": {}}, "Generalizations of the teleportation protocol": {"''d''-dimensional systems": {}, "Multipartite versions": {}}, "Logic gate teleportation": {"General description": {}, "Further details": {}}, "Local explanation of the phenomenon": {}, "Recent developments": {"Higher dimensions": {}, "Information quality": {}}, "See also": {}, "References": {"Specific": {}, "General": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Quantum teleportation --- Introduction ---|Experimental results and records": "Work in 1998 verified the initial predictions,<ref name="Rome1998">{{cite journal\n|journal=[[Physical Review Letters]]\n|volume=80\n|issue=6\n|pages=1121\u20131125\n|doi= 10.1103/PhysRevLett.80.1121\n|title=Experimental Realization of Teleporting an Unknown Pure Quantum State via Dual Classical and Einstein-Podolsky-Rosen Channels\n|author=D. Boschi\n|author2=S. Branca |author3=F. De Martini |author4=L. Hardy |author5=S. Popescu\n |date=1998\n|arxiv = quant-ph/9710013 |bibcode = 1998PhRvL..80.1121B |s2cid=15020942\n}}</ref> and the distance of teleportation was increased in August 2004 to 600 meters, using [[optical fiber]].<ref name="Danube2004">{{cite journal\n|title=Quantum teleportation across the Danube\n|author=Rupert Ursin\n|date=August 2004\n|journal=Nature\n|volume=430\n|issue=7002\n|doi=10.1038/430849a\n|pmid=15318210\n|page=849\n|bibcode=2004Natur.430..849U\n|s2cid=4426035\n}}</ref> Subsequently, the record distance for quantum teleportation has been gradually increased to {{convert|16|km}},<ref>{{cite journal|title=Experimental free-space quantum teleportation|first1=Xian-Min|last1=Jin|first2=Ji-Gang|last2=Ren|first3=Bin|last3=Yang|first4=Zhen-Huan|last4=Yi|first5=Fei|last5=Zhou|first6=Xiao-Fan|last6=Xu|first7=Shao-Kai|last7=Wang|first8=Dong|last8=Yang|first9=Yuan-Feng|last9=Hu|first10=Shuo|last10=Jiang|first11=Tao|last11=Yang|first12=Hao|last12=Yin|first13=Kai|last13=Chen|first14=Cheng-Zhi|last14=Peng|first15=Jian-Wei|last15=Pan|date=16 May 2010|journal=Nature Photonics|volume=4|issue=6|pages=376|doi=10.1038/nphoton.2010.87|bibcode=2010NaPho...4..376J}}</ref> then to {{cvt|97|km}},<ref name=":1">{{cite journal|title=Quantum teleportation over 143 kilometres using active feed-forward|first1=Xiao-Song|last1=Ma|first2=Thomas|last2=Herbst|first3=Thomas|last3=Scheidl|first4=Daqing|last4=Wang|first5=Sebastian|last5=Kropatschek|first6=William|last6=Naylor|first7=Bernhard|last7=Wittmann|first8=Alexandra|last8=Mech|first9=Johannes|last9=Kofler|first10=Elena|last10=Anisimova|first11=Vadim|last11=Makarov|first12=Thomas|last12=Jennewein|first13=Rupert|last13=Ursin|first14=Anton|last14=Zeilinger|date=5 September 2012|journal=Nature|volume=489|issue=7415|pages=269\u201373|doi=10.1038/nature11472|pmid=22951967|bibcode=2012Natur.489..269M|arxiv=1205.3909|s2cid=209109}}</ref> and is now {{cvt|143|km}}, set in open air experiments in the [[Canary Islands]], done between the two [[Astronomical observatory|astronomical observatories]] of the [[Instituto de Astrof\u00edsica de Canarias]].<ref name="ReferenceA">{{Cite journal|last2=Herbst|first2=T.|last3=Scheidl|first3=T.|last4=Wang|first4=D.|last5=Kropatschek|first5=S.|last6=Naylor|first6=W.|last7=Wittmann|first7=B.|last8=Mech|first8=A.|last9=Kofler|first9=J.|display-authors=8|date=2012|title=Quantum teleportation over 143 kilometres using active feed-forward|journal=Nature|volume=489|issue=7415|pages=269\u2013273|bibcode=2012Natur.489..269M|doi=10.1038/nature11472|pmid=22951967|last1=Ma|first1=X. S.|arxiv=1205.3909|s2cid=209109}}</ref>  There has been a recent record set ({{As of|2015|September|lc=y}}) using superconducting nanowire detectors that reached the distance of {{cvt|102|km|mi}} over optical fiber.<ref>{{cite journal|last1=Takesue|first1=Hiroki|display-authors=etal|title=Quantum teleportation over 100 km of fiber using highly efficient superconducting nanowire single-photon detectors|journal=Optica|date=2015-10-20|volume=2|issue=10|pages=832\u2013835|doi=10.1364/OPTICA.2.000832|arxiv=1510.00476|bibcode=2015Optic...2..832T|s2cid=55109707}}</ref>  For material systems, the record distance is {{convert|21|m}}.<ref>{{Cite journal|arxiv=1212.3127|last1=N\u00f6lleke|first1=Christian|title=Efficient Teleportation between Remote Single-Atom Quantum Memories|journal=Physical Review Letters|volume=110|issue=14|pages=140403|last2=Neuzner|first2=Andreas|last3=Reiserer|first3=Andreas|last4=Hahn|first4=Carolin|last5=Rempe|first5=Gerhard|last6=Ritter|first6=Stephan|year=2013|doi=10.1103/PhysRevLett.110.140403|pmid=25166964|bibcode=2013PhRvL.110n0403N|s2cid=6597459}}</ref>\n\nA variant of teleportation called "open-destination" teleportation, with receivers located at multiple locations, was demonstrated in 2004 using five-photon entanglement.<ref>{{Cite journal | doi=10.1038/nature02643| pmid=15229594| title=Experimental demonstration of five-photon entanglement and open-destination teleportation| journal=Nature| volume=430| issue=6995| pages=54\u201358| year=2004| last1=Zhao| first1=Zhi| last2=Chen| first2=Yu-Ao| last3=Zhang| first3=An-Ning| last4=Yang| first4=Tao| last5=Briegel| first5=Hans J.| last6=Pan| first6=Jian-Wei| bibcode=2004Natur.430...54Z| arxiv=quant-ph/0402096| s2cid=4336020}}</ref> Teleportation of a composite state of two single qubits has also been realized.<ref>{{Cite journal |arxiv = quant-ph/0609129|doi = 10.1038/nphys417|title = Experimental quantum teleportation of a two-qubit composite system|journal = Nature Physics|volume = 2|issue = 10|pages = 678\u2013682|year = 2006|last1 = Zhang|first1 = Qiang|last2 = Goebel|first2 = Alexander|last3 = Wagenknecht|first3 = Claudia|last4 = Chen|first4 = Yu-Ao|last5 = Zhao|first5 = Bo|last6 = Yang|first6 = Tao|last7 = Mair|first7 = Alois|last8 = Schmiedmayer|first8 = J\u00f6rg|last9 = Pan|first9 = Jian-Wei|bibcode = 2006NatPh...2..678Z|s2cid = 18201599}}</ref> In April 2011, experimenters reported that they had demonstrated teleportation of wave packets of light up to a bandwidth of 10 MHz while preserving strongly nonclassical superposition states.<ref name="Lee2011">{{cite journal|last=Lee|first=Noriyuki|author2=Hugo Benichi|author3=Yuishi Takeno|author4=Shuntaro Takeda|author5=James Webb|author6-link=Elanor Huntington|author6=Elanor Huntington|author7=Akira Furusawa|date=April 2011|title=Teleportation of Nonclassical Wave Packets of Light|journal=Science|volume=332|issue=6027|pages=330\u2013333|arxiv=1205.6253|bibcode=2011Sci...332..330L|citeseerx=10.1.1.759.1059|doi=10.1126/science.1201034|pmid=21493853|s2cid=206531447}}</ref><ref name=NewQuantTelep>{{cite web|last=Trute|first=Peter|title=Quantum teleporter breakthrough|url=http://www.unsw.edu.au/news/pad/articles/2011/apr/Quantum_teleport_paper.html|publisher=The University Of New South Wales|access-date=17 April 2011}}</ref>  In August 2013, the achievement of "fully deterministic" quantum teleportation, using a hybrid technique, was reported.<ref>Takeda et al., [http://www.nature.com/nature/journal/v500/n7462/abs/nature12366.html "Deterministic quantum teleportation of photonic quantum bits by a hybrid technique"], ''Nature'', August 2013.</ref> On 29 May 2014, scientists announced a reliable way of transferring data by quantum teleportation. Quantum teleportation of data had been done before but with highly unreliable methods.<ref name="NYT-20140529">{{cite news |last=Markoff |first=John |title=Scientists Report Finding Reliable Way to Teleport Data |url=https://www.nytimes.com/2014/05/30/science/scientists-report-finding-reliable-way-to-teleport-data.html |date=29 May 2014 |work=[[The New York Times]] |access-date=29 May 2014 }}</ref><ref name="SCI-20140529">{{cite journal |author=Pfaff, W. |title=Unconditional quantum teleportation between distant solid-state quantum bits |date=29 May 2014 |journal=[[Science (journal)|Science]] |doi=10.1126/science.1253512 |arxiv = 1404.4369 |bibcode = 2014Sci...345..532P |display-authors=etal |volume=345 |issue=6196 |pages=532\u2013535 |pmid=25082696|s2cid=2190249 }}</ref> On 26 February 2015, scientists at the [[University of Science and Technology of China]] in Hefei, led by [[Chao-yang Lu]] and [[Jian-Wei Pan]] carried out the first experiment teleporting multiple degrees of freedom of a quantum particle. They managed to teleport the quantum information from ensemble of rubidium atoms to another ensemble of rubidium atoms over a distance of {{convert|150|m}} using entangled photons.<ref>{{cite web|title=Two quantum properties teleported together for first time|url=http://physicsworld.com/cws/article/news/2015/feb/27/two-quantum-properties-teleported-together-for-first-time|publisher=PhysicsWorld.com|date=27 February 2015}}</ref><ref name=nature-20150226>{{cite journal |last=Wang |first=Xi-Lin |author2=Xin-Dong Cai |author3=Zu-En Su |author4=Ming-Cheng Chen |author5=Dian Wu |author6=Li Li |author7=Nai-Le Liu | author8=Chao-Yang Lu | author9=Jian-Wei Pan |date=26 February 2015 |title=Quantum teleportation of multiple degrees of freedom of a single photon |journal=Nature |volume=518 |issue=7540 |pages=516\u2013519 |doi=10.1038/nature14246 |pmid=25719668 |bibcode=2015Natur.518..516W |s2cid=4448594 }}</ref><ref name="Quantum Science and Technology">{{cite journal |last=Xia |first=Xiu-Xiu |author2=Qi-Chao Sun |author3=Qiang Zhang |author4=Jian-Wei Pan |date=2018 |title=Long distance quantum teleportation |journal=Quantum Science and Technology |volume=3 |issue= 1|pages=014012 |doi=10.1088/2058-9565/aa9baf |bibcode=2018QS&T....3a4012X }}</ref> In 2016, researchers demonstrated quantum teleportation with two independent sources which are separated by {{cvt|6.5|km}} in Hefei optical fiber network.<ref>{{Cite journal|last1=Sun|first1=Qi-Chao|last2=Mao|first2=Ya-Li|last3=Chen|first3=Sijing|last4=Zhang|first4=Wei|last5=Jiang|first5=Yang-Fan|last6=Zhang|first6=Yanbao|last7=Zhang|first7=Weijun|last8=Miki|first8=Shigehito|last9=Yamashita|first9=Taro|last10=Terai|first10=Hirotaka|last11=Jiang|first11=Xiao|last12=Chen|first12=Teng-Yun|last13=You|first13=Lixing|last14=Chen|first14=Xianfeng|last15=Wang|first15=Zhen|last16=Fan|first16=Jingyun|last17=Zhang|first17=Qiang|last18=Pan|first18=Jian-Wei|date=2016-09-19|title=Quantum teleportation with independent sources and prior entanglement distribution over a network|journal=Nature Photonics|language=En|volume=10|issue=10|pages=671\u2013675|doi=10.1038/nphoton.2016.179|issn=1749-4893|arxiv=1602.07081|bibcode=2016NaPho..10..671S}}</ref> In September 2016, researchers at the University of Calgary demonstrated quantum teleportation over the Calgary metropolitan fiber network over a distance of {{cvt|6.2|km}}.<ref>{{Cite journal|last1=Valivarthi|first1=Raju|last2=Puigibert|first2=Marcel.li Grimau|last3=Zhou|first3=Qiang|last4=Aguilar|first4=Gabriel H.|last5=Verma|first5=Varun B.|last6=Marsili|first6=Francesco|last7=Shaw|first7=Matthew D.|last8=Nam|first8=Sae Woo|last9=Oblak|first9=Daniel|date=2016-09-19|title=Quantum teleportation across a metropolitan fibre network|journal=Nature Photonics|volume=10|issue=10|pages=676\u2013680|doi=10.1038/nphoton.2016.180|issn=1749-4885|arxiv=1605.08814|bibcode=2016NaPho..10..676V|s2cid=119163338}}</ref> In December of 2020, as part of the INQNET collaboration, researchers achieved quantum teleportation over a total distance of 44 km (27.3 mi) with fidelities exceeding 90%.<ref>{{Cite journal|last=Valivarthi|first=Raju|last2=Davis|first2=Samantha I.|last3=Pe\u00f1a|first3=Cristi\u00e1n|last4=Xie|first4=Si|last5=Lauk|first5=Nikolai|last6=Narv\u00e1ez|first6=Lautaro|last7=Allmaras|first7=Jason P.|last8=Beyer|first8=Andrew D.|last9=Gim|first9=Yewon|last10=Hussein|first10=Meraj|last11=Iskander|first11=George|date=2020-12-04|title=Teleportation Systems Toward a Quantum Internet|url=https://link.aps.org/doi/10.1103/PRXQuantum.1.020317|journal=PRX Quantum|language=en|volume=1|issue=2|pages=020317|doi=10.1103/PRXQuantum.1.020317|issn=2691-3399}}</ref><ref>{{Cite web|title=Researchers achieve first "sustained" long distance quantum teleportation|url=https://futurism.com/researchers-achieve-first-sustained-long-distance-quantum-teleportation|access-date=2021-06-06|website=Futurism}}</ref>\n\nResearchers have also successfully used quantum teleportation to transmit information between clouds of gas atoms, notable because the clouds of gas are macroscopic atomic ensembles.<ref>{{cite web|title=Quantum teleportation between atomic systems over long distances|url=http://phys.org/news/2013-06-quantum-teleportation-atomic-distances.html|publisher=Phys.Org}}</ref><ref>{{cite journal|title=Deterministic quantum teleportation between distant atomic objects|first1=H.|last1=Krauter|first2=D.|last2=Salart|first3=C. A.|last3=Muschik|first4=J. M.|last4=Petersen|first5=Heng|last5=Shen|first6=T.|last6=Fernholz|first7=E. S.|last7=Polzik|date=2 June 2013|journal=Nature Physics|volume=9|issue=7|pages=400|doi=10.1038/nphys2631|arxiv=1212.6746|bibcode=2013NatPh...9..400K|s2cid=118724313}}</ref>\n\nIt is also possible to teleport ''logical operations'', see [[quantum gate teleportation]]. In 2018, physicists at Yale demonstrated a deterministic teleported [[Controlled NOT gate|CNOT]] operation between [[Quantum error correction#Bosonic codes|logically encoded]] qubits.<ref>{{Cite journal |arxiv = 1801.05283|doi = 10.1038/s41586-018-0470-y|pmid = 30185908|title = Deterministic teleportation of a quantum gate between two logical qubits|journal = Nature|volume = 561|issue = 7723|pages = 368\u2013373|year = 2018|last1 = Chou|first1 = Kevin S.|last2 = Blumoff|first2 = Jacob Z.|last3 = Wang|first3 = Christopher S.|last4 = Reinhold|first4 = Philip C.|last5 = Axline|first5 = Christopher J.|last6 = Gao|first6 = Yvonne Y.|last7 = Frunzio|first7 = L.|last8 = Devoret|first8 = M. H.|last9 = Jiang|first9 = Liang|last10 = Schoelkopf|first10 = R. J.|bibcode = 2018Natur.561..368C|s2cid = 3820071}}</ref>\n\nFirst proposed theoretically in 1993, quantum teleportation has since been demonstrated in many different guises. It has been carried out using two-level states of a single photon, a single atom and a trapped ion \u2013 among other quantum objects \u2013 and also using two photons. In 1997, two groups experimentally achieved quantum teleportation. The first group, led by [[Sandu Popescu]], was based out Italy. An experimental group led by [[Anton Zeilinger]] followed a few months later.\n\nThe results obtained from experiments done by Popescu's group concluded that classical channels alone could not replicate the teleportation of linearly polarized state and an elliptically polarized state. The Bell state measurement distinguished between the four Bell states, which can allow for a 100% success rate of teleportation, in an ideal representation.<ref>{{Cite journal|last=Boschi|first=D.|last2=Branca|first2=S.|last3=De Martini|first3=F.|last4=Hardy|first4=L.|last5=Popescu|first5=S.|date=1998-02-09|title=Experimental Realization of Teleporting an Unknown Pure Quantum State via Dual Classical and Einstein-Podolsky-Rosen Channels|url=https://link.aps.org/doi/10.1103/PhysRevLett.80.1121|journal=Physical Review Letters|volume=80|issue=6|pages=1121\u20131125|doi=10.1103/PhysRevLett.80.1121|arxiv=quant-ph/9710013}}</ref>\n\nZeilinger's group produced a pair of entangled photons by implementing the process of parametric down-conversion. In order to ensure that the two photons cannot be distinguished by their arrival times, the photons were generated using a pulsed pump beam. The photons were then sent through narrow-bandwidth filters to produce a coherence time that is much longer than the length of the pump pulse. They then used a two-photon interferometry for analyzing the entanglement so that the quantum property could be recognized when it is transferred from one photon to the other.<ref name=":02">{{Cite journal|last=Bouwmeester|first=Dik|last2=Pan|first2=Jian-Wei|last3=Mattle|first3=Klaus|last4=Eibl|first4=Manfred|last5=Weinfurter|first5=Harald|last6=Zeilinger|first6=Anton|date=1997-12-11|title=Experimental quantum teleportation|url=https://www.nature.com/articles/37539|journal=Nature|language=en|volume=390|issue=6660|pages=575\u2013579|doi=10.1038/37539|issn=1476-4687|arxiv=1901.11004}}</ref>\n\nPhoton 1 was polarized at 45\u00b0 in the first experiment conducted by Zeilinger's group. Quantum teleportation is verified when both photons are detected in the <math>|\\Psi^-\\rangle_{12}</math> state, which has a probability of 25%. Two detectors, f1 and f2, are placed behind the beam splitter, and recording the coincidence will identify the <math>|\\Psi^-\\rangle_{12}</math> state. If there is a coincidence between detectors f1 and f2, then photon 3 is predicted to be polarized at a 45\u00b0 angle. Photon 3 is passed through a polarizing beam splitter that selects +45\u00b0 and -45\u00b0 polarization. If quantum teleportation has happened, only detector d2, which is at the +45\u00b0 output, will register a detection. Detector d1, located at the -45\u00b0 output, will not detect a photon. If there is a coincidence between d2f1f2, with the 45\u00b0 analysis, and a lack of a d1f1f2 coincidence, with -45\u00b0 analysis, it is proof that the information from the polarized photon 1 has been teleported to photon 3 using quantum teleportation.<ref name=":02" />\n\n \nZeilinger's group developed an experiment using active feed-forward in real time and two free-space optical links, quantum and classical, between the Canary Islands of La Palma and Tenerife, a distance of over 143 kilometers. In order to achieve teleportation, a frequency-uncorrelated polarization-entangled photon pair source, ultra-low-noise single-photon detectors and entanglement assisted clock synchronization were implemented. The two locations were entangled to share the auxiliary state:<ref name=":1" />\n\n:<math>|\\Psi^-\\rangle_{23}=\\frac{1}{\\surd2}((|H\\rangle_2|V\\rangle_3)-(|V\\rangle_2|H\\rangle_3))</math>\n\nLa Palma and Tenerife can be compared to the quantum characters Alice and Bob. Alice and Bob share the entangled state above, with photon 2 being with Alice and photon 3 being with Bob. A third party, Charlie, provides photon 1 (the input photon) which will be teleported to Alice in the generalized polarization state:\n\n:<math>|\\phi\\rangle_1=\\alpha|H\\rangle_1+\\beta|V\\rangle_1</math>\n\nwhere the complex numbers <math>\\alpha</math> and <math>\\beta</math> are unknown to Alice or Bob.\n\nAlice will perform a Bell-state measurement (BSM) that randomly projects the two photons onto one of the four Bell states with each one having a probability of 25%. Photon 3 will be projected onto <math>|\\phi\\rangle</math>, the input state. Alice transmits the outcome of the BSM to Bob, via the classical channel, where Bob is able to apply the corresponding unitary operation to obtain photon 3 in the initial state of photon 1. Bob will not have to do anything if he detects the <math>|\\psi^-\\rangle_{12}</math> state. Bob will need to apply a <math>\\pi</math> phase shift to photon 3 between the horizontal and vertical component if the <math>|\\psi^+\\rangle_{12}</math> state is detected.<ref name=":1" />\n\nThe results of Zeilinger's group concluded that the average fidelity (overlap of the ideal teleported state with the measured density matrix) was 0.863 with a standard deviation of 0.038. The link attenuation during their experiments varied between 28.1 dB and 39.0 dB, which was a result of strong winds and rapid temperature changes. Despite the high loss in the quantum free-space channel, the average fidelity surpassed the classical limit of 2/3. Therefore, Zeilinger's group successfully demonstrated quantum teleportation over a distance of 143 km.<ref name=":1" />\n\n In 2004, a quantum teleportation experiment was conducted across the Danube River in Vienna, a total of 600 meters. An 800-meter-long optical fiber wire was installed in a public sewer system underneath the Danube River, and it was exposed to temperature changes and other environmental influences. Alice must perform a joint Bell state measurement (BSM) on photon b, the input photon, and photon c, her part of the entangled photon pair (photons c and d). Photon d, Bob's receiver photon, will contain all of the information on the input photon b, except for a phase rotation that depends on the state that Alice observed. This experiment implemented an active feed-forward system that sends Alice's measurement results via a classical microwave channel with a fast electro-optical modulator in order to exactly replicate Alice's input photon. The teleportation fidelity obtained from the linear polarization state at 45\u00b0 varied between 0.84 and 0.90, which is well above the classical fidelity limit of 0.66.<ref name="Danube2004" />\n\n Three qubits are required for this process: the source qubit from the sender, the ancillary qubit, and the receiver's target qubit, which is maximally entangled with the ancillary qubit. For this experiment, <chem>^{40}Ca+</chem> ions were used as the qubits. Ions 2 and 3 are prepared in the Bell state <math>|\\psi^+\\rangle_{23}=\\frac{1}{\\sqrt{2}}(|0\\rangle_2|1\\rangle_3+|1\\rangle_2|0\\rangle_3)</math>. The state of ion 1 is prepared arbitrarily. The quantum states of ions 1 and 2 are measured by illuminating them with light at a specific wavelength. The obtained fidelities for this experiment ranged between 73% and 76%. This is larger than the maximum possible average fidelity of 66.7% that can be obtained using completely classical resources.<ref>{{Cite journal|last=Riebe|first=M.|last2=H\u00e4ffner|first2=H.|last3=Roos|first3=C. F.|last4=H\u00e4nsel|first4=W.|last5=Benhelm|first5=J.|last6=Lancaster|first6=G. P. T.|last7=K\u00f6rber|first7=T. W.|last8=Becher|first8=C.|last9=Schmidt-Kaler|first9=F.|last10=James|first10=D. F. V.|last11=Blatt|first11=R.|date=2004|title=Deterministic quantum teleportation with atoms|url=https://www.nature.com/articles/nature02570|journal=Nature|language=en|volume=429|issue=6993|pages=734\u2013737|doi=10.1038/nature02570|issn=1476-4687}}</ref>\n\n The quantum state being teleported in this experiment is <math>|\\chi\\rangle_1=\\alpha|H\\rangle_1+\\beta|V\\rangle_1</math>, where <math>\\alpha</math> and <math>\\beta</math> are unknown complex numbers, <math>|H\\rangle</math> represents the horizontal polarization state, and <math>|V\\rangle</math> represents the vertical polarization state. The qubit prepared in this state is generated in a laboratory in Ngari, Tibet. The goal was to teleport the quantum information of the qubit to the Micius satellite that was launched on August 16, 2016 at an altitude of around 500 km. When a Bell state measurement is conducted on photons 1 and 2 and the resulting state is <math>|\\phi^+\\rangle_{12}=\\frac{1}{\\sqrt{2}}(|H\\rangle_1|H\\rangle_2+|V\\rangle_1|V\\rangle_2))</math>, photon 3 carries this desired state. If the Bell state detected is <math>|\\phi^-\\rangle_{12}=\\frac{1}{\\sqrt{2}}(|H\\rangle_1|H\\rangle_2-|V\\rangle_1|V\\rangle_2)</math>, then a phase shift of <math>\\pi</math> is applied to the state to get the desired quantum state. The distance between the ground station and the satellite changes from as little as 500 km to as large as 1,400 km. Because of the changing distance, the channel loss of the uplink varies between 41 dB and 52 dB. The average fidelity obtained from this experiment was 0.80 with a standard deviation of 0.01. Therefore, this experiment successfully established a ground-to-satellite uplink over a distance of 500-1,400 km using quantum teleportation. This is an essential step towards creating a global-scale quantum internet.<ref>{{Cite journal|last=Ren|first=Ji-Gang|last2=Xu|first2=Ping|last3=Yong|first3=Hai-Lin|last4=Zhang|first4=Liang|last5=Liao|first5=Sheng-Kai|last6=Yin|first6=Juan|last7=Liu|first7=Wei-Yue|last8=Cai|first8=Wen-Qi|last9=Yang|first9=Meng|last10=Li|first10=Li|last11=Yang|first11=Kui-Xing|date=2017-08-09|title=Ground-to-satellite quantum teleportation|url=https://www.nature.com/articles/nature23675/|journal=Nature|language=en|volume=549|issue=7670|pages=70\u201373|doi=10.1038/nature23675|issn=1476-4687|arxiv=1707.00934}}</ref>"}},
{"article_title": "Radar", "pageid": "25676", "revid": "1062226222", "timestamp": "2021-12-27T04:12:40Z", "history_paths": [["Radar --- Introduction ---", "History"]], "categories": ["radar", "avionics", "aircraft instruments", "microwave technology", "measuring instruments", "navigational equipment", "air traffic control", "science and technology during world war ii", "targeting (warfare)", "radio stations and systems itu", "1940s neologisms", "wireless communication systems"], "heading_tree": {"Radar --- Introduction ---": {"History": {"First experiments": {}, "Just before World War II": {}, "During World War II": {}}, "Applications": {}, "Principles": {"Radar signal": {}, "Illumination": {}, "Reflection": {}, "Radar range equation": {}, "Doppler effect": {}, "Polarization": {}, "Limiting factors": {"Beam path and range": {}, "Noise": {}, "Interference": {}, "Clutter": {}, "Jamming": {}}}, "Radar signal processing": {"Distance measurement": {"Transit time": {}, "Frequency modulation": {}, "Pulse compression": {}}, "Speed measurement": {}, "Pulse-Doppler signal processing": {}, "Reduction of interference effects": {}, "Plot and track extraction": {}}, "Engineering": {"Antenna design": {"Parabolic reflector": {}, "Types of scan": {}, "Slotted waveguide": {}, "Phased array": {}}, "Frequency bands": {}, "Modulators": {}, "Coolant": {}}, "Regulations": {}, "Configurations": {}, "See also": {}, "Notes and references": {}, "Bibliography": {"References": {}, "General": {}, "Technical reading": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Radar --- Introduction ---|History": "{{Main|History of radar}}\n\n As early as 1886, German physicist [[Heinrich Hertz]] showed that radio waves could be reflected from solid objects. In 1895, [[Alexander Stepanovich Popov|Alexander Popov]], a physics instructor at the [[Imperial Russian Navy]] school in [[Kronstadt]], developed an apparatus using a [[coherer]] tube for detecting distant lightning strikes. The next year, he added a [[spark-gap transmitter]]. In 1897, while testing this equipment for communicating between two ships in the [[Baltic Sea]], he took note of an [[interference beat]] caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, but he did nothing more with this observation.<ref>Kostenko, A.A., A.I. Nosich, and I.A. Tishchenko, "Radar Prehistory, Soviet Side," ''Proc. of IEEE APS International Symposium 2001,'' vol. 4. p. 44, 2003</ref>\n\nThe German inventor [[Christian H\u00fclsmeyer]] was the first to use radio waves to detect "the presence of distant metallic objects". In 1904, he demonstrated the feasibility of detecting a ship in dense fog, but not its distance from the transmitter.<ref name="RadarWorld">{{cite web|url=http://www.radarworld.org/huelsmeyer.html|title=Christian Huelsmeyer, the inventor|work=radarworld.org}}</ref> He obtained a patent<ref>[//upload.wikimedia.org/wikipedia/commons/1/11/DE165546.pdf ''Patent DE165546; Verfahren, um metallische Gegenst\u00e4nde mittels elektrischer Wellen einem Beobachter zu melden.'']</ref> for his detection device in April 1904 and later a patent<ref>[//upload.wikimedia.org/wikipedia/commons/e/e9/DE169154.pdf ''Verfahren zur Bestimmung der Entfernung von metallischen Gegenst\u00e4nden (Schiffen o. dgl.), deren Gegenwart durch das Verfahren nach Patent 16556 festgestellt wird.'']</ref> for a related amendment for estimating the distance to the ship. He also obtained a British patent on September 23, 1904<ref>{{patent|GB|13170|''Telemobiloscope''}} {{Dead link|date=June 2020}}</ref> for a full radar system, that he called a ''telemobiloscope''. It operated on a 50 cm wavelength and the pulsed radar signal was created via a spark-gap. His system already used the classic antenna setup of horn antenna with parabolic reflector and was presented to German military officials in practical tests in [[Cologne]] and [[Rotterdam]] harbour but was rejected.<ref>{{cite web|url=http://100-jahre-radar.fraunhofer.de/img/gdr_zeichnungpatent.jpg | title= gdr_zeichnungpatent.jpg | access-date= February 24, 2015}}</ref>\n\nIn 1915, [[Robert Watson-Watt]] used radio technology to provide advance warning to airmen<ref>{{cite news|title=Making waves: Robert Watson-Watt, the pioneer of radar|url=https://www.bbc.co.uk/news/uk-scotland-tayside-central-27393558|publisher=BBC|date=16 February 2017}}</ref> and during the 1920s went on to lead the U.K. research establishment to make many advances using radio techniques, including the probing of the [[ionosphere]] and the detection of [[lightning]] at long distances. Through his lightning experiments, Watson-Watt became an expert on the use of [[radio direction finding]] before turning his inquiry to [[shortwave]] transmission. Requiring a suitable receiver for such studies, he told the "new boy" [[Arnold Frederic Wilkins]] to conduct an extensive review of available shortwave units. Wilkins would select a [[General Post Office]] model after noting its manual's description of a "fading" effect (the common term for interference at the time) when aircraft flew overhead.\n\nAcross the Atlantic in 1922, after placing a transmitter and receiver on opposite sides of the [[Potomac River]], U.S. Navy researchers [[A. Hoyt Taylor]] and [[Leo C. Young]] discovered that ships passing through the beam path caused the received signal to fade in and out. Taylor submitted a report, suggesting that this phenomenon might be used to detect the presence of ships in low visibility, but the Navy did not immediately continue the work. Eight years later, [[Lawrence A. Hyland]] at the [[Naval Research Laboratory]] (NRL) observed similar fading effects from passing aircraft; this revelation led to a patent application<ref>Hyland, L.A, A.H. Taylor, and L.C. Young; "System for detecting objects by radio," U.S. Patent No. 1981884, granted 27 Nov. 1934</ref> as well as a proposal for further intensive research on radio-echo signals from moving targets to take place at NRL, where Taylor and Young were based at the time.<ref>{{cite book|last=Howeth|first=Linwood S.|chapter=Ch. XXXVIII Radar|title=History of Communications-Electronics in the United States Navy|date=1963|publisher=Washington|chapter-url=https://babel.hathitrust.org/cgi/pt?id=uiug.30112064674325;view=1up;seq=475}}</ref>\n\nSimilarly, in the UK, L. S. Alder took out a secret provisional patent for Naval radar in 1928.\n<ref>{{cite book |last1=Coales |first1=J.F. |title=The Origins and Development of Radar in the Royal Navy, 1935\u201345 with Particular Reference to Decimetric Gunnery Equipments |date=1995 |publisher=Springer |isbn=978-1-349-13457-1 |pages=5\u201366}}</ref>\n[[W. A. S. Butement|W.A.S. Butement]] and P. E. Pollard developed a breadboard test unit, operating at 50 cm (600 MHz) and using pulsed modulation which gave successful laboratory results. In January 1931, a writeup on the apparatus was entered in the ''Inventions Book'' maintained by the Royal Engineers. This is the first official record in Great Britain of the technology that was used in Coastal Defence and was incorporated into [[Chain Home]] as [[Chain Home Low|Chain Home (low)]].<ref>Butement, W. A. S., and P. E. Pollard; "Coastal Defence Apparatus", ''Inventions Book of the Royal Engineers Board'', Jan. 1931</ref><ref>Swords, S. S.; ''tech. History of the Beginnings of Radar'', Peter Peregrinus, Ltd, 1986, pp. 71\u201374</ref>\n\n [[File:Early radar antenna - US Naval Research Laboratory Anacostia.jpg|thumb|upright=0.8|Experimental radar antenna, US [[Naval Research Laboratory]], Anacostia, D. C., late 1930s]]\nBefore the [[Second World War]], researchers in the [[United Kingdom]], [[French Third Republic|France]], [[Nazi Germany|Germany]], [[Kingdom of Italy|Italy]], [[Japanese Empire|Japan]], the [[Netherlands]], the [[Soviet Union]], and the [[United States]], independently and in great secrecy, developed technologies that led to the modern version of radar. [[Australia]], [[Canada]], [[New Zealand]], and [[South Africa]] followed prewar Great Britain's radar development, and [[Regency of Hungary|Hungary]] generated its radar technology during the war.<ref>{{cite book| last= Watson |first=Raymond C., Jr.| title = Radar Origins Worldwide: History of Its Evolution in 13 Nations Through World War II| url = https://books.google.com/books?id=g-rQQgAACAAJ| date = 2009-11-25| publisher = Trafford Publishing| isbn = 978-1-4269-2111-7 }}</ref>\n\nIn France in 1934, following systematic studies on the [[Cavity Magnetron#Split-anode magnetron|split-anode magnetron]], the research branch of the [[Thomson-CSF|Compagnie G\u00e9n\u00e9rale de T\u00e9l\u00e9graphie Sans Fil]] (CSF) headed by Maurice Ponte with Henri Gutton, Sylvain Berline and M. Hugon, began developing an obstacle-locating radio apparatus, aspects of which were installed on the ocean liner [[SS Normandie|''Normandie'']] in 1935.<ref>{{cite magazine|title= Radio Waves Warn Liner of Obstacles in Path|magazine= Popular Mechanics|url= https://books.google.com/books?id=x98DAAAAMBAJ&pg=PA844|date= December 1935|publisher= Hearst Magazines|page= 844}}</ref><ref>Frederick Seitz, Norman G. Einspruch, Electronic Genie: The Tangled History of Silicon  - 1998 - page 104</ref>\n\nDuring the same period, Soviet military engineer [[Pavel K. Oshchepkov|P.K. Oshchepkov]], in collaboration with the [[Saint Petersburg State Electrotechnical University|Leningrad Electrotechnical Institute]], produced an experimental apparatus, RAPID, capable of detecting an aircraft within 3 km of a receiver.<ref>John Erickson. Radio-Location and the Air Defence Problem: The Design and Development of Soviet Radar. ''Science Studies'', vol. 2, no. 3 (Jul., 1972), pp. 241\u2013263</ref> The Soviets produced their first mass production radars RUS-1 and RUS-2 Redut in 1939 but further development was slowed following the arrest of Oshchepkov and his subsequent [[gulag]] sentence. In total, only 607 Redut stations were produced during the war. The first Russian airborne radar, [[Gneiss-2]], entered into service in June 1943 on [[Petlyakov Pe-2|Pe-2]] dive bombers. More than 230 Gneiss-2 stations were produced by the end of 1944.<ref>{{cite web | url=http://kret.com/en/news/3657/ | title=The history of radar, from aircraft radio detectors to airborne radar | work=kret.com | date=February 17, 2015 | access-date=April 28, 2015 | url-status=dead | archive-url=https://web.archive.org/web/20150620161506/http://kret.com/en/news/3657/ | archive-date=20 June 2015 | df=dmy-all }}</ref> The French and Soviet systems, however, featured continuous-wave operation that did not provide the full performance ultimately synonymous with modern radar systems.\n\nFull radar evolved as a pulsed system, and the first such elementary apparatus was demonstrated in December 1934 by the American [[Robert Morris Page|Robert M. Page]], working at the [[Naval Research Laboratory]].<ref>Page, Robert Morris, ''The Origin of Radar'', Doubleday Anchor, New York, 1962, p. 66</ref> The following year, the [[United States Army]] successfully tested a primitive surface-to-surface radar to aim [[Coastal artillery|coastal battery]] [[searchlight]]s at night.<ref>{{cite magazine|title= Mystery Ray Locates 'Enemy'|magazine= Popular Science|url= https://books.google.com/books?id=bygDAAAAMBAJ&pg=PA29|date= October 1935|publisher= Bonnier Corporation|page= 29}}</ref> This design was followed by a pulsed system demonstrated in May 1935 by [[Rudolf K\u00fchnhold]] and the firm {{ill|Gesellschaft f\u00fcr elektroakustische und mechanische Apparate|lt=GEMA|de|GEMA (Radar)}} in Germany and then another in June 1935 by an [[Air Ministry]] team led by [[Robert Watson-Watt]] in Great Britain.\n\n[[File:Watson Radar.jpg|thumb|left|The first workable unit built by [[Robert Watson-Watt]] and his team]]\nIn 1935, Watson-Watt was asked to judge recent reports of a German radio-based [[death ray]] and turned the request over to Wilkins. Wilkins returned a set of calculations demonstrating the system was basically impossible. When Watson-Watt then asked what such a system might do, Wilkins recalled the earlier report about aircraft causing radio interference. This revelation led to the [[Daventry Experiment]] of 26 February 1935, using a powerful [[BBC]] shortwave transmitter as the source and their GPO receiver setup in a field while a bomber flew around the site. When the plane was clearly detected, [[Hugh Dowding]], the [[Air Member for Supply and Research]] was very impressed with their system's potential and funds were immediately provided for further operational development.<ref name="dora">{{cite web|url=http://www.doramusic.com/Radar.htm |title=The story of RADAR Development |author=Alan Dower Blumlein |year=2002 |access-date=2011-05-06 |url-status=dead |archive-url=https://web.archive.org/web/20110710144447/http://www.doramusic.com/Radar.htm |archive-date=10 July 2011 }}</ref> Watson-Watt's team patented the device in GB593017.<ref name="radar net">{{cite web|language=fr|url=http://www.radar-france.fr/brevet%20radar1934.htm|title=Nouveau syst\u00e8me de rep\u00e9rage d'obstacles et ses applications|trans-title=New obstacle detection system and its applications|url-status=dead|archive-url=https://web.archive.org/web/20090116093441/http://www.radar-france.fr/brevet%20radar1934.htm|archive-date=16 January 2009|work=BREVET D'INVENTION|date=20 July 1934|via=www.radar-france.fr}}</ref><ref>{{cite press release|url=http://www.patent.gov.uk/media/pressrelease/2001/1009.htm|title=British man first to patent radar|date=10 September 2001|website=Media Centre|publisher=The Patent Office|url-status=dead|archive-url=https://web.archive.org/web/20060719224405/http://www.patent.gov.uk/media/pressrelease/2001/1009.htm|archive-date=19 July 2006}}</ref><ref>{{patent|GB|593017|''Improvements in or relating to wireless systems''}}</ref>\n\n[[File:Chain home.jpg|thumb|upright=0.65|A [[Chain Home]] tower in Great Baddow, Essex, United Kingdom]]\n[[File:Watson watt 02 fr.jpg|thumb|left|Memorial plaque commemorating Robert Watson-Watt and [[Arnold Wilkins]]]]\nDevelopment of radar greatly expanded on 1 September 1936 when Watson-Watt became Superintendent of a new establishment under the British [[Air Ministry]], Bawdsey Research Station located in [[Bawdsey Manor]], near Felixstowe, Suffolk. Work there resulted in the design and installation of aircraft detection and tracking stations called "[[Chain Home]]" along the East and South coasts of England in time for the outbreak of World War II in 1939. This system provided the vital advance information that helped the Royal Air Force win the [[Battle of Britain]]; without it, significant numbers of fighter aircraft, which Great Britain did not have available, would always need to be in the air to respond quickly. If enemy aircraft detection had relied solely on the observations of ground-based individuals, Great Britain might have lost the Battle of Britain. Also vital was the "[[Dowding system]]" of reporting and coordination to provide the best use of radar information during the tests of early radar [[Chain Home#Deployment|deployment]] during 1936 and 1937.\n\nGiven all required funding and development support, the team produced working radar systems in 1935 and began deployment. By 1936, the first five [[Chain Home]] (CH) systems were operational and by 1940 stretched across the entire UK including Northern Ireland. Even by standards of the era, CH was crude; instead of broadcasting and receiving from an aimed antenna, CH broadcast a signal floodlighting the entire area in front of it, and then used one of Watson-Watt's own radio direction finders to determine the direction of the returned echoes. This fact meant CH transmitters had to be much more powerful and have better antennas than competing systems but allowed its rapid introduction using existing technologies.\n\n {{main|Radar in World War II}}\nA key development was the [[cavity magnetron]] in the UK, which allowed the creation of relatively small systems with sub-meter resolution. Britain shared the technology with the U.S. during the 1940 [[Tizard Mission]].<ref name=Hind>{{cite news|url=http://news.bbc.co.uk/1/hi/sci/tech/6331897.stm |title=Briefcase 'that changed the world' |work=BBC News |author=Angela Hind |date=February 5, 2007 |access-date=2007-08-16 |quote=It not only changed the course of the war by allowing us to develop airborne radar systems, it remains the key piece of technology that lies at the heart of your microwave oven today. The cavity magnetron's invention changed the world.}}</ref><ref>{{cite news|last1=Harford|first1=Tim|title=How the search for a 'death ray' led to radar|url=https://www.bbc.co.uk/news/business-41188464|access-date=9 October 2017|work=BBC World Service|date=9 October 2017|quote=But by 1940, it was the British who had made a spectacular breakthrough: the resonant cavity magnetron, a radar transmitter far more powerful than its predecessors.... The magnetron stunned the Americans. Their research was years off the pace.}}</ref>\n\nIn April 1940, ''[[Popular Science]]'' showed an example of a radar unit using the Watson-Watt patent in an article on air defence.<ref>{{cite magazine|title= Night Watchmen of the Skies|magazine= Popular Science|url= https://books.google.com/books?id=hCcDAAAAMBAJ&pg=PA56|date= December 1941|publisher= Bonnier Corporation|page= 56}}</ref> Also, in late 1941 ''Popular Mechanics'' had an article in which a U.S. scientist speculated about the British early warning system on the English east coast and came close to what it was and how it worked.<ref name="Hearst Magazines 26">{{cite magazine|title=Odd-shaped Boats Rescue British Engineers|magazine= Popular Mechanics|url= https://archive.org/details/bub_gb_mtkDAAAAMBAJ/page/n67|date= September 1941|publisher= Hearst Magazines|page= 26}}</ref> Watson-Watt was sent to the U.S. in 1941 to advise on air defense after Japan's [[attack on Pearl Harbor]].<ref>{{cite news|title=Scotland's little-known WWII hero who helped beat the Luftwaffe with invention of radar set to be immortalised in film|url=http://www.dailyrecord.co.uk/news/real-life/scotlands-little-known-wwii-hero-who-3882904|newspaper=Daily Record|date=16 February 2017}}</ref> [[Alfred Lee Loomis]] organized the secret [[MIT Radiation Laboratory]] at [[Massachusetts Institute of Technology]], Cambridge, Massachusetts which developed microwave radar technology in the years 1941\u201345. Later, in 1943, Page greatly improved radar with the [[Monopulse radar|monopulse technique]] that was used for many years in most radar applications.<ref>{{cite web | last=Goebel | first=Greg | title=The Wizard War: WW2 & The Origins Of Radar | url=http://www.vectorsite.net/ttwiz_01.html | date=2007-01-01 | access-date=2007-03-24}}</ref>\n\nThe war precipitated research to find better resolution, more portability, and more features for radar, including complementary navigation systems like [[Oboe (navigation)|Oboe]] used by the [[Pathfinder (RAF)|RAF's Pathfinder]]."}},
{"article_title": "RNA", "pageid": "25758", "revid": "1061716387", "timestamp": "2021-12-23T13:18:05Z", "history_paths": [["RNA --- Introduction ---", "Key discoveries in RNA biology"]], "categories": ["rna", "rna splicing", "molecular biology", "biotechnology", "nucleic acids"], "heading_tree": {"RNA --- Introduction ---": {"Comparison with DNA": {}, "Structure": {}, "Synthesis": {}, "Types of RNA": {"Overview": {}, "In length": {}, "In translation": {}}, "Regulatory RNA": {"RNA interference by miRNAs": {}, "Long non-coding RNAs": {}, "Enhancer RNAs": {}, "Regulatory RNA in prokaryotes": {}}, "In RNA processing": {}, "RNA genomes": {"In reverse transcription": {}}, "Double-stranded RNA": {}, "Circular RNA": {}, "Key discoveries in RNA biology": {"Relevance for prebiotic chemistry and abiogenesis": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"RNA --- Introduction ---|Key discoveries in RNA biology": "{{further|History of RNA biology}}\n[[File:R Holley.jpg|thumb|210px|Robert W. Holley, left, poses with his research team.]]\nResearch on RNA has led to many important biological discoveries and numerous [[Nobel Prize|Nobel Prizes]]. [[Nucleic acid]]s were discovered in 1868 by [[Friedrich Miescher]], who called the material 'nuclein' since it was found in the [[Cell nucleus|nucleus]].<ref>{{cite journal | vauthors = Dahm R | title = Friedrich Miescher and the discovery of DNA | journal = Developmental Biology | volume = 278 | issue = 2 | pages = 274\u201388 | date = February 2005 | pmid = 15680349 | doi = 10.1016/j.ydbio.2004.11.028 | doi-access = free }}</ref> It was later discovered that prokaryotic cells, which do not have a nucleus, also contain nucleic acids. The role of RNA in protein synthesis was suspected already in 1939.<ref>{{cite journal|journal=Nature | vauthors = Caspersson T, Schultz J | title = Pentose nucleotides in the cytoplasm of growing tissues|date=1939|volume=143|doi=10.1038/143602c0|pages=602\u201303|issue=3623|bibcode=1939Natur.143..602C| s2cid = 4140563 }}</ref> [[Severo Ochoa]] won the 1959 [[Nobel Prize in Medicine]] (shared with [[Arthur Kornberg]]) after he discovered an enzyme that can synthesize RNA in the laboratory.<ref>{{cite web | vauthors = Ochoa S | title = Enzymatic synthesis of ribonucleic acid|work=Nobel Lecture|date=1959|url=http://nobelprize.org/nobel_prizes/medicine/laureates/1959/ochoa-lecture.pdf}}</ref> However, the enzyme discovered by Ochoa ([[polynucleotide phosphorylase]]) was later shown to be responsible for RNA degradation, not RNA synthesis. In 1956 Alex Rich and David Davies hybridized two separate strands of RNA to form the first crystal of RNA whose structure could be determined by X-ray crystallography.<ref>{{cite journal | vauthors = Rich A, Davies D |title=A New Two-Stranded Helical Structure: Polyadenylic Acid and Polyuridylic Acid|journal=Journal of the American Chemical Society|date=1956|volume=78|issue=14|doi=10.1021/ja01595a086|pages=3548\u201349}}</ref>\n\nThe sequence of the 77 nucleotides of a yeast tRNA was found by [[Robert W. Holley]] in 1965,<ref>{{cite journal | vauthors = Holley RW, Apgar J, Everett GA, Madison JT, Marquisee M, Merrill SH, Penswick JR, Zamir A | title = Structure of a ribonucleic acid | journal = Science | volume = 147 | issue = 3664 | pages = 1462\u201365 | date = March 1965 | pmid = 14263761 | doi = 10.1126/science.147.3664.1462 | bibcode = 1965Sci...147.1462H | s2cid = 40989800 | display-authors = 1 }}</ref> winning Holley the [[List of Nobel laureates in Physiology or Medicine|1968 Nobel Prize in Medicine]] (shared with [[Har Gobind Khorana]] and [[Marshall Nirenberg]]).\n\nIn the early 1970s, [[retrovirus]]es and [[reverse transcriptase]] were discovered, showing for the first time that enzymes could copy RNA into DNA (the opposite of the usual route for transmission of genetic information). For this work, [[David Baltimore]], [[Renato Dulbecco]] and [[Howard Temin]] were awarded a Nobel Prize in 1975.\nIn 1976, [[Walter Fiers]] and his team determined the first complete nucleotide sequence of an RNA virus genome, that of [[bacteriophage MS2]].<ref>{{cite journal | vauthors = Fiers W, Contreras R, Duerinck F, Haegeman G, Iserentant D, Merregaert J, Min Jou W, Molemans F, Raeymaekers A, Van den Berghe A, Volckaert G, Ysebaert M | title = Complete nucleotide sequence of bacteriophage MS2 RNA: primary and secondary structure of the replicase gene | journal = Nature | volume = 260 | issue = 5551 | pages = 500\u201307 | date = April 1976 | pmid = 1264203 | doi = 10.1038/260500a0 | bibcode = 1976Natur.260..500F | s2cid = 4289674 | display-authors = 1 }}</ref>\n\nIn 1977, [[intron]]s and [[RNA splicing]] were discovered in both mammalian viruses and in cellular genes, resulting in a 1993 Nobel to [[Philip A. Sharp|Philip Sharp]] and [[Richard J. Roberts|Richard Roberts]].\nCatalytic RNA molecules ([[ribozyme]]s) were discovered in the early 1980s, leading to a 1989 Nobel award to [[Thomas Cech]] and [[Sidney Altman]]. In 1990, it was found in ''[[Petunia]]'' that introduced genes can silence similar genes of the plant's own, now known to be a result of [[RNA interference]].<ref>{{cite journal | vauthors = Napoli C, Lemieux C, Jorgensen R | title = Introduction of a Chimeric Chalcone Synthase Gene into Petunia Results in Reversible Co-Suppression of Homologous Genes in trans | journal = The Plant Cell | volume = 2 | issue = 4 | pages = 279\u201389 | date = April 1990 | pmid = 12354959 | pmc = 159885 | doi = 10.1105/tpc.2.4.279 }}</ref><ref>{{cite journal | vauthors = Dafny-Yelin M, Chung SM, Frankman EL, Tzfira T | title = pSAT RNA interference vectors: a modular series for multiple gene down-regulation in plants | journal = Plant Physiology | volume = 145 | issue = 4 | pages = 1272\u201381 | date = December 2007 | pmid = 17766396 | pmc = 2151715 | doi = 10.1104/pp.107.106062 }}</ref>\n\nAt about the same time, 22 nt long RNAs, now called [[microRNA]]s, were found to have a role in the [[developmental biology|development]] of ''[[Caenorhabditis elegans|C. elegans]]''.<ref>{{cite journal | vauthors = Ruvkun G | s2cid = 83506718 | title = Molecular biology. Glimpses of a tiny RNA world | journal = Science | volume = 294 | issue = 5543 | pages = 797\u201399 | date = October 2001 | pmid = 11679654 | doi = 10.1126/science.1066315 }}</ref>\nStudies on RNA interference gleaned a Nobel Prize for [[Andrew Z. Fire|Andrew Fire]] and [[Craig Mello]] in 2006, and another Nobel was awarded for studies on the transcription of RNA to [[Roger Kornberg]] in the same year. The discovery of gene regulatory RNAs has led to attempts to develop drugs made of RNA, such as [[siRNA]], to silence genes.<ref>{{cite journal | vauthors = Fichou Y, F\u00e9rec C | title = The potential of oligonucleotides for therapeutic applications | journal = Trends in Biotechnology | volume = 24 | issue = 12 | pages = 563\u201370 | date = December 2006 | pmid = 17045686 | doi = 10.1016/j.tibtech.2006.10.003 }}</ref> Adding to the Nobel prizes awarded for research on RNA in 2009 it was awarded for the elucidation of the atomic structure of the ribosome to Venki Ramakrishnan, Tom Steitz, and Ada Yonath.\n\n In 1968, [[Carl Woese]] hypothesized that RNA might be catalytic and suggested that the earliest forms of life (self-replicating molecules) could have relied on RNA both to carry genetic information and to catalyze biochemical reactions\u2014an [[RNA world hypothesis|RNA world]].<ref>{{cite web|url=http://deposit.ddb.de/cgi-bin/dokserv?idn=982323891&dok_var=d1&dok_ext=pdf&filename=982323891.pdf|title=Common sequence structure properties and stable regions in RNA secondary structures|date=2006|work=Dissertation, Albert-Ludwigs-Universit\u00e4t, Freiburg im Breisgau|page=1|archive-url=https://web.archive.org/web/20120309212648/http://deposit.ddb.de/cgi-bin/dokserv?idn=982323891&dok_var=d1&dok_ext=pdf&filename=982323891.pdf|archive-date=March 9, 2012|url-status=dead|vauthors=Siebert S}}</ref><ref>{{cite journal | vauthors = Szathm\u00e1ry E | title = The origin of the genetic code: amino acids as cofactors in an RNA world | journal = Trends in Genetics | volume = 15 | issue = 6 | pages = 223\u201329 | date = June 1999 | pmid = 10354582 | doi = 10.1016/S0168-9525(99)01730-8 }}</ref>\n\nIn March 2015, complex [[DNA]] and RNA [[nucleotide]]s, including [[uracil]], [[cytosine]] and [[thymine]], were reportedly formed in the laboratory under [[outer space]] conditions, using starter chemicals, such as [[pyrimidine]], an [[organic compound]] commonly found in [[meteorite]]s. [[Pyrimidine]], like [[polycyclic aromatic hydrocarbons]] (PAHs), is one of the most carbon-rich compounds found in the [[Universe]] and may have been formed in [[red giant]]s or in [[Cosmic dust|interstellar dust]] and gas clouds.<ref name="NASA-20150303">{{cite web|url=http://www.nasa.gov/content/nasa-ames-reproduces-the-building-blocks-of-life-in-laboratory|title=NASA Ames Reproduces the Building Blocks of Life in Laboratory|last=Marlaire|first=Ruth | name-list-style = vanc |date=3 March 2015|work=[[NASA]]|access-date=5 March 2015}}</ref>"}},
{"article_title": "Real-time computing", "pageid": "25767", "revid": "1061594050", "timestamp": "2021-12-22T17:22:14Z", "history_paths": [["Real-time computing --- Introduction ---", "History"]], "categories": ["real-time computing", "real-time technology"], "heading_tree": {"Real-time computing --- Introduction ---": {"History": {}, "{{anchor|Hard|Firm|Require|Soft}}Criteria for real-time computing": {"Real-time in digital signal processing": {"Live vs. real-time": {}}}, "Real-time and high-performance": {}, "{{Anchor|Near real-time}}Near real-time": {}, "Design methods": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Real-time computing --- Introduction ---|History": "The term ''real-time'' derives from its use in early [[simulation]], in which a real-world process is simulated at a rate that matched that of the real process (now called [[real-time simulation]] to avoid ambiguity). [[Analog computer]]s, most often, were capable of simulating at a much faster pace than real-time, a situation that could be just as dangerous as a slow simulation if it were not also recognized and accounted for. <!-- What does this mean? Where did "dangerous" become an issue? --><!-- The historical origins of the term has no bearing on its current, correct, technical definition. ''Real-time'' does not refer to either fast or slow processing. In fact, the speed of processing is independent of whether it is considered ''real-time'' or not. For a system to be defined as ''real-time'' it must meet its time constraints \u2014 whether those constraints require extremely fast processing or can be met at a more leisurely pace has no bearing on the matter. -->\n\nMinicomputers, particularly in the 1970s onwards, when built into dedicated [[embedded system]]s such as DOG ([[Digital on-screen graphic]]) scanners, increased the need for low-latency priority-driven responses to important interactions with incoming data and so operating systems such as [[Data General]]'s [[Data General RDOS|RDOS (Real-Time Disk Operating System)]] and RTOS with [[Foreground-background|background and foreground scheduling]] as well as [[Digital Equipment Corporation]]'s [[RT-11]] date from this era. Background-foreground scheduling allowed low priority tasks CPU time when no foreground task needed to execute, and gave absolute priority within the foreground to threads/tasks with the highest priority. Real-time operating systems would also be used for [[time-sharing]] multiuser duties. For example, [[Data General Business Basic]] could run in the foreground or background of RDOS and would introduce additional elements to the scheduling algorithm to make it more appropriate for people interacting via [[dumb terminal]]s.\n\n{{Disputed section|The 68000 Was a CPU, not a Computer|date=October 2020}}\nOnce when the [[MOS Technology 6502]] (used in the [[Commodore 64]] and [[Apple II]]), and later when the [[Motorola 68000]] (used in the [[Macintosh]], [[Atari ST]], and [[Commodore Amiga]]) were popular, anybody could use their home computer as a real-time system. The possibility to deactivate other interrupts allowed for hard-coded loops with defined timing, and the low [[interrupt latency]] allowed the implementation of a real-time operating system, giving the user interface and the disk drives lower priority than the real-time thread. Compared to these the [[programmable interrupt controller]] of the Intel CPUs (8086..80586) generates a very large latency and the Windows operating system is neither a real-time operating system nor does it allow a program to take over the CPU completely and use its own [[Scheduling (computing)|scheduler]], without using native machine language and thus surpassing all interrupting Windows code. However, several coding libraries exist which offer real time capabilities in a high level language on a variety of operating systems, for example [[Real time Java|Java Real Time]]. The [[Motorola 68000]] and subsequent family members (68010, 68020 etc.) also became popular with manufacturers of industrial control systems. This application area is one in which real-time control offers genuine advantages in terms of process performance and safety.{{citation needed|date=September 2013|reason=This whole paragraph contains several questionable statements in regard to MOS, AMD and Motorola CPUs and their interrupt handling, and therefore needs to be rewritten and sourced by reliable sources.}}"}},
{"article_title": "Renewable energy", "pageid": "25784", "revid": "1063009966", "timestamp": "2021-12-31T18:52:16Z", "history_paths": [["Renewable energy --- Introduction ---", "History"]], "categories": ["renewable energy", "renewable energy technology", "low-carbon economy", "technological change", "bright green environmentalism"], "heading_tree": {"Renewable energy --- Introduction ---": {"Overview": {}, "History": {}, "Mainstream technologies": {"Hydropower": {}, "Wind power": {}, "Solar energy": {}, "Bioenergy": {}, "Geothermal energy": {}}, "Emerging technologies": {"Enhanced geothermal system": {}, "Cellulosic ethanol": {}, "Marine energy": {}, "Solar energy developments": {"Experimental solar power": {}, "Floating solar arrays": {}, "Perovskite solar cells": {}, "Solar-assisted heat pump": {}, "Solar aircraft": {}, "Solar updraft tower": {}, "Space-based solar power": {}}, "Artificial photosynthesis": {}, "Others": {"Algae fuels": {}, "Water vapor": {}, "Crop wastes": {}}}, "Integration into the energy system": {"Electrical energy storage": {}}, "Market and industry trends{{anchor|Economic_trends}}": {"Growth of renewables": {"Future projections": {}}, "Demand": {}, "Trends for individual technologies": {"Hydroelectricity": {}, "Wind power development": {}, "Solar thermal": {}, "Photovoltaic development": {}, "Biofuel development": {}, "Geothermal development": {}}, "Developing countries": {}}, "Policy": {"Policy trends": {}, "Full renewable energy": {}}, "Debate": {}, "Geopolitics of renewable energy": {}, "Environmental impact": {"Biomass": {}, "Conservation areas, recycling and rare-earth elements": {}}, "Gallery": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Renewable energy --- Introduction ---|History": "Prior to the development of coal in the mid 19th century, nearly all energy used was renewable. The oldest known use of renewable energy, in the form of traditional [[biomass]] to [[Control of fire by early humans|fuel fires]], dates from more than a million years ago. The use of biomass for fire did not become commonplace until many hundreds of thousands of years later.<ref name=Fire>{{cite web|title=The Discovery of Fire|url=http://archaeology.about.com/od/ancientdailylife/qt/fire_control.htm|publisher=[[About.com]]|access-date=15 January 2013|author=K. Kris Hirst|archive-date=12 January 2013|archive-url=https://web.archive.org/web/20130112213352/http://archaeology.about.com/od/ancientdailylife/qt/fire_control.htm|url-status=live}}</ref> Probably the second oldest usage of renewable energy is harnessing the wind in order to drive ships over water. This practice can be traced back some 7000 years, to ships in the Persian Gulf and on the Nile.<ref>{{cite encyclopedia|title=wind energy|encyclopedia=[[The Encyclopedia of Alternative Energy and Sustainable Living]]|url=http://www.daviddarling.info/encyclopedia/W/AE_wind_energy.html|access-date=15 January 2013|archive-date=26 January 2013|archive-url=https://web.archive.org/web/20130126061929/http://www.daviddarling.info/encyclopedia/W/AE_wind_energy.html|url-status=live}}</ref> From [[hot spring]]s, geothermal energy has been used for bathing since [[Paleolithic]] times and for space heating since ancient Roman times.<ref>{{cite web|url=http://faculty.fairfield.edu/mediacenter/nm_webdesign/s_zandan/sz_alt_energy/geothermal_energy.html|title=Geothermal Energy|website=faculty.fairfield.edu|access-date=17 January 2017|archive-date=25 March 2017|archive-url=https://web.archive.org/web/20170325214438/http://faculty.fairfield.edu/mediacenter/nm_webdesign/s_zandan/sz_alt_energy/geothermal_energy.html|url-status=live}}</ref> Moving into the time of recorded history, the primary sources of traditional renewable energy were human [[Manual labour|labor]], [[animal power]], [[water power]], wind, in grain crushing [[windmill]]s, and [[firewood]], a traditional biomass.\n\nIn the 1860s and 1870s, there were already fears that civilization would run out of fossil fuels and the need was felt for a better source. In 1873 [[Augustin Mouchot]] wrote:\n{{quote|\ntext=\nThe time will arrive when the industry of Europe will cease to find those natural resources, so necessary for it. Petroleum springs and coal mines are not inexhaustible but are rapidly diminishing in many places.  Will man, then, return to the power of water and wind? Or will he emigrate where the most powerful source of heat sends its rays to all?  History will show what will come.<ref>{{Cite web|last=Kovarik|first=Bill|date=2011-03-29|title=The surprising history of sustainable energy|url=https://sustainablehistory.wordpress.com/2011/03/29/the-surprising-history-of-sustainable-energy/|access-date=2020-12-11|website=History of sustainable energy|language=en|archive-date=28 February 2021|archive-url=https://web.archive.org/web/20210228232639/https://sustainablehistory.wordpress.com/2011/03/29/the-surprising-history-of-sustainable-energy/|url-status=live}}</ref>}}\nIn 1885, [[Werner von Siemens]], commenting on the discovery of the [[photovoltaic effect]] in the solid state, wrote:\n{{quote|\ntext=In conclusion, I would say that however great the scientific importance of this discovery may be, its practical value will be no less obvious when we reflect that the supply of solar energy is both without limit and without cost, and that it will continue to pour down upon us for countless ages after all the coal deposits of the earth have been exhausted and forgotten.<ref>{{Cite journal|last=Siemens|first=Werner|date=June 1885|title=On the electro motive action of illuminated selenium, discovered by Mr. Fritts, of New York|journal=Journal of the Franklin Institute|language=en|volume=119|issue=6|pages=453\u2013IN6|doi=10.1016/0016-0032(85)90176-0|url=https://zenodo.org/record/1779030|access-date=26 February 2021|archive-date=6 May 2021|archive-url=https://web.archive.org/web/20210506135319/https://zenodo.org/record/1779030|url-status=live}}</ref>}}\n[[Max Weber]] mentioned the end of fossil fuel in the concluding paragraphs of his [[Die protestantische Ethik und der Geist des Kapitalismus]] (The Protestant Ethic and the Spirit of Capitalism), published in 1905.<ref>Weber suggests that the modern economic world will determine the lifestyle of everyone born into it "until the last [[hundredweight]] of fossil fuel is burned" (''[http://www.zeno.org/Soziologie/M/Weber,+Max/Schriften+zur+Religionssoziologie/Die+protestantische+Ethik+und+der+Geist+des+Kapitalismus/II.+Die+Berufsethik+des+asketischen+Protestantismus/2.+Askese+und+kapitalistischer+Geist bis der letzte Zentner fossilen Brennstoffs vergl\u00fcht ist] {{Webarchive|url=https://web.archive.org/web/20180825212624/http://www.zeno.org/Soziologie/M/Weber,+Max/Schriften+zur+Religionssoziologie/Die+protestantische+Ethik+und+der+Geist+des+Kapitalismus/II.+Die+Berufsethik+des+asketischen+Protestantismus/2.+Askese+und+kapitalistischer+Geist |date=25 August 2018 }}'').</ref> Development of solar engines continued until the outbreak of World War I. The importance of solar energy was recognized in a 1911 ''[[Scientific American]]'' article: "in the far distant future, [[Fossil fuel|natural fuels]] having been exhausted [solar power] will remain as the only means of existence of the human race".<ref>[http://www.hbs.edu/research/pdf/12-105.pdf "Power from Sunshine": A Business History of Solar Energy] {{Webarchive|url=https://web.archive.org/web/20121010213555/http://www.hbs.edu/research/pdf/12-105.pdf |date=10 October 2012 }} 25 May 2012</ref>\n\nThe theory of [[peak oil]] was published in 1956.<ref>{{cite web |url=http://www.hubbertpeak.com/hubbert/1956/1956.pdf |title=Nuclear Energy and the Fossil Fuels |author=Hubbert, M. King |author-link=M. King Hubbert |publisher=[[Shell Oil Company]]/[[American Petroleum Institute]] |date=June 1956 |access-date=10 November 2014 |url-status=dead |archive-url=https://web.archive.org/web/20080527233843/http://www.hubbertpeak.com/hubbert/1956/1956.pdf |archive-date=27 May 2008 }}</ref> In the 1970s environmentalists promoted the development of renewable energy both as a replacement for the eventual [[depletion of oil]], as well as for an escape from dependence on oil, and the first electricity-generating [[wind turbine]]s appeared. Solar had long been used for heating and cooling, but solar panels were too costly to build solar farms until 1980.<ref>{{cite web|url=http://www.solarstartechnologies.com/id69.html |title=History of PV Solar |publisher=Solarstartechnologies.com |access-date=1 November 2012| archive-date=6 December 2013|url-status=dead| archive-url= https://web.archive.org/web/20131206133548/http://solarstartechnologies.com/id69.html}}</ref>"}},
{"article_title": "Code refactoring", "pageid": "25871", "revid": "1062411853", "timestamp": "2021-12-28T08:46:09Z", "history_paths": [["Code refactoring --- Introduction ---", "History"]], "categories": ["code refactoring", "extreme programming", "technology neologisms"], "heading_tree": {"Code refactoring --- Introduction ---": {"Motivation": {}, "Benefits": {}, "Challenges": {}, "Testing": {}, "Techniques": {}, "Hardware refactoring": {}, "History": {}, "Automated code refactoring": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Code refactoring --- Introduction ---|History": "The first known use of the term "refactoring" in the published literature was in a September, 1990 article by [[William Opdyke]] and [[Ralph Johnson (computer scientist)|Ralph Johnson]].<ref name="opdyke90">{{cite conference\n  | first = William F.\n  | last = Opdyke\n  | author-link = William Opdyke\n  |author2=Johnson, Ralph E.\n  | title = Refactoring: An Aid in Designing Application Frameworks and Evolving Object-Oriented Systems\n  | book-title = Proceedings of the Symposium on Object Oriented Programming Emphasizing Practical Applications (SOOPPA)\n  | publisher = ACM\n  |date=September 1990\n}}</ref>\nGriswold's Ph.D. thesis,<ref name="griswold-thesis">{{cite thesis\n  | first = William G\n  | last = Griswold\n  | author-link = Bill Griswold\n  | title = Program Restructuring as an Aid to Software Maintenance\n  | degree = Ph.D.\n  | publisher = University of Washington\n  |date=July 1991\n  | url = http://cseweb.ucsd.edu/~wgg/Abstracts/gristhesis.pdf\n  | access-date = 2011-12-24\n}}</ref>\nOpdyke's Ph.D. thesis,<ref name="opdyke-thesis">{{cite thesis\n  | first = William F\n  | last = Opdyke\n  | author-link = William Opdyke\n  | title = Refactoring Object-Oriented Frameworks\n  | degree = Ph.D.\n  | publisher = University of Illinois at Urbana-Champaign\n  | date = June 1992\n  | url = http://dl.acm.org/citation.cfm?id=169783\n  | archive-url = https://dl.acm.org/citation.cfm?id=169783\n  | archive-date = 2019-12-16\n  | format = compressed Postscript\n  | access-date = 2008-02-12\n  }}</ref> published in 1992, also used this term.<ref name="etymology" /> Although refactoring code has been done informally for decades, [[Bill Griswold|William Griswold]]'s 1991 Ph.D. dissertation<ref name="griswold-thesis" /> is one of the first major academic works on refactoring functional and procedural programs, followed by [[William Opdyke]]'s 1992 dissertation<ref name="opdyke-thesis" /> on the refactoring of object-oriented programs,<ref name="etymology">[http://martinfowler.com/bliki/EtymologyOfRefactoring.html Martin Fowler, "MF Bliki: EtymologyOfRefactoring"]</ref> although all the theory and machinery have long been available as [[program transformation]] systems. All of these resources provide a catalog of common methods for refactoring; a refactoring method has a description of how to apply the [[Scientific method|method]] and indicators for when you should (or should not) apply the method.\n\n[[Martin Fowler (software engineer)|Martin Fowler]]'s book ''Refactoring: Improving the Design of Existing Code'' is the canonical reference. {{According to whom|date=July 2018}}\n\nThe terms "factoring" and "factoring out" have been used in this way in the [[Forth (programming language)|Forth]] community since at least the early 1980s. Chapter Six of [[Leo Brodie (programmer)|Leo Brodie]]'s book ''[[Thinking Forth]]'' (1984)<ref>{{cite book \n |last1=Brodie \n |first1=Leo \n |title=Thinking Forth \n |year=2004 \n |isbn=0-9764587-0-5 \n |pages=171\u2013196 \n |url=http://thinking-forth.sourceforge.net \n |access-date=3 May 2020 \n |archive-url=https://web.archive.org/web/20051216163615/http://thinking-forth.sourceforge.net/ \n |archive-date=16 December 2005 \n |url-status=dead \n }}</ref> is dedicated to the subject.\n\nIn extreme programming, the Extract Method refactoring technique has essentially the same meaning as factoring in Forth; to break down a "word" (or [[Function (programming)|function]]) into smaller, more easily maintained functions.\n\nRefactorings can also be reconstructed<ref name="What-is-code-refactoring?">{{cite news\n  | first = Andriy\n  | last = Sokolov\n  | title = What is code refactoring?\n  | url = https://duecode.io/blog/what-is-code-refactoring/\n  }}</ref> posthoc to produce concise descriptions of complex software changes recorded in software repositories like CVS or SVN."}},
{"article_title": "Reciprocating engine", "pageid": "25995", "revid": "1057783145", "timestamp": "2021-11-29T17:09:02Z", "history_paths": [["Reciprocating engine --- Introduction ---", "History"]], "categories": ["piston engines", "engine technology"], "heading_tree": {"Reciprocating engine --- Introduction ---": {"Common features in all types": {}, "History": {}, "Engine capacity": {}, "Power": {}, "Other modern non-internal combustion types": {}, "Reciprocating quantum heat engine": {}, "Miscellaneous engines": {}, "See also": {}, "Notes": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Reciprocating engine --- Introduction ---|History": "{{further information|History of the steam engine|History of the internal combustion engine}}\n\nAn early known example of rotary to reciprocating motion is the [[Crank (mechanism)|crank]] mechanism. The earliest hand-operated cranks appeared in [[China]] during the [[Han Dynasty]] (202 BC\u2013220 AD).<ref name="needham volume 4 part 2 118">Needham, Joseph. (1986). Science and Civilization in China: Volume 4, Part 2, Mechanical Engineering. Taipei: Caves Books, Ltd. Pages 118\u2013119.</ref> The Chinese used the crank-and-connecting rod for operating querns as far back as the Western Han dynasty (202 BC - 9 AD). Eventually crank-and-connecting rods were used in the inter-conversion of rotary and reciprocating motion for other applications such as flour-sifting, silk-reeling machines, treadle spinning wheels, and furnace bellows driven either by horses or waterwheels. <ref name="Yan">{{cite book |author=Hong-Sen Yan, Marco Ceccarelli |title=International Symposium on History of Machines and Mechanisms |url=https://books.google.com/books?id=Dkq6_mdW43IC&q=han+dynasty+crank+and+connecting+rod&pg=PA249 |publisher=Springer Science and Business Media|isbn=978-1-4020-9484-2|page=235\u2013249|year=2009 }}</ref><ref name="needham volume 4 part 2 118" /> Several [[saw mill]]s in [[Roman Asia]] and [[Byzantine Syria]] during the 3rd\u20136th centuries AD had a crank and [[connecting rod]] mechanism which converted the rotary motion of a [[water wheel]] into the linear movement of saw blades.<ref name="Tullia et al. (2007) 161">{{citation|last1=Ritti|first1=Tullia|last2=Grewe|first2= Klaus|last3=Kessener|first3=Paul|title=A Relief of a Water-powered Stone Saw Mill on a Sarcophagus at Hierapolis and its Implications|journal=Journal of Roman Archaeology|pages=138\u2013163|volume=20| year=2007|doi=10.1017/S1047759400005341|s2cid=161937987}}</ref> In 1206, Arab engineer [[Al-Jazari]] invented a [[crankshaft]].<ref name=Ganchy>{{citation|title=Islam and Science, Medicine, and Technology|last=Sally Ganchy|first=Sarah Gancher|publisher=The Rosen Publishing Group|year=2009|isbn=978-1-4358-5066-8|page=[https://archive.org/details/islamsciencemedi0000ganc/page/41 41]|url-access=registration|url=https://archive.org/details/islamsciencemedi0000ganc/page/41}}</ref>\n\nThe reciprocating engine developed in Europe during the 18th century, first as the [[atmospheric engine]] then later as the [[steam engine]]. These were followed by the [[Stirling engine]] and [[internal combustion engine]] in the 19th century. Today the most common form of reciprocating engine is the internal combustion engine running on the combustion of [[petrol]], [[Diesel fuel|diesel]], [[Liquefied petroleum gas]] (LPG) or [[compressed natural gas]] (CNG) and used to power [[motor vehicle]]s and [[engine power plant]]s.\n\nOne notable reciprocating engine from the World War II Era was the 28-cylinder, {{convert|3500|hp|kW|lk=in|abbr=on}} [[Pratt & Whitney R-4360 Wasp Major]] radial engine. It powered the last generation of large piston-engined planes before jet engines and turboprops took over from 1944 onward. It had a total engine capacity of {{convert|71.5|L|cuin|abbr=on}}, and a high power-to-weight ratio.\n\nThe largest reciprocating engine in production at present, but not the largest ever built, is the [[W\u00e4rtsil\u00e4-Sulzer RTA96-C]]  turbocharged two-stroke diesel engine of 2006 built by [[W\u00e4rtsil\u00e4]]. It is used to power the largest modern container ships such as the [[Emma M\u00e6rsk]]. It is five stories high ({{convert|13.5|m|ft|disp=or|abbr=on}}), {{convert|27|m|ft|0|abbr=on}} long, and weighs over {{convert|2,300|metric ton|short ton}} in its largest 14 cylinders version producing more than 84.42 MW (114,800 bhp). Each cylinder has a capacity of {{convert|1,820|L|cuft|0|abbr=on}}, making a total capacity of {{convert|25,480|L|cuft|0|abbr=on}} for the largest versions."}},
{"article_title": "Rotary engine", "pageid": "26103", "revid": "1062308369", "timestamp": "2021-12-27T17:37:55Z", "history_paths": [["Rotary engine --- Introduction ---", "History"]], "categories": ["engine technology", "piston engine configurations", "motorcycle engines", "rotary engines"], "heading_tree": {"Rotary engine --- Introduction ---": {"Description": {"Distinction between \"rotary\" and \"radial\" engines": {}, "Arrangement": {}, "Advantages and drawbacks": {}}, "Rotary engine control": {"Monosoupape rotaries": {}, "\"Normal\" rotaries": {}}, "History": {"Millet": {}, "Hargrave": {}, "Balzer": {}, "De Dion-Bouton": {}, "Adams-Farwell": {}, "Gnome": {}, "World War I": {"Siemens-Halske bi-rotary designs": {}}, "Postwar": {}}, "Use in cars and motorcycles": {}, "Other rotary engines": {}, "See also": {}, "Notes": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Rotary engine --- Introduction ---|History": "[[File:Felix Millet.jpg|right|thumb|An 1897 F\u00e9lix Millet motorcycle.]]\n[[F\u00e9lix Millet]] showed a 5-cylinder rotary engine built into a bicycle wheel at the [[Exposition Universelle (1889)|Exposition Universelle]] in Paris in 1889. Millet had patented the engine in 1888, so must be considered the pioneer of the internal combustion rotary engine. A machine powered by his engine took part in the Paris-Bordeaux-Paris race of 1895 and the system was put into production by [[Darracq and Company London]] in 1900.<ref name="nahum20">{{cite book| last = Nahum| first = Andrew| title = The Rotary Aero Engine| year = 1999| publisher = NMSI Trading Ltd| isbn = 1-900747-12-X| pages = 20 }}</ref>\n\n \n[[Lawrence Hargrave]] first developed a rotary engine in 1889 using compressed air, intending to use it in powered flight. Materials weight and lack of quality machining prevented it becoming an effective power unit.<ref>[http://www.adb.online.anu.edu.au/biogs/A090194b.htm Hargrave, Lawrence (1850 \u2013 1915)] {{Webarchive|url=https://web.archive.org/web/20110524142500/http://www.adb.online.anu.edu.au/biogs/A090194b.htm |date=2011-05-24 }}. Australian Dictionary of Biography Online.</ref>\n\n \n[[Stephen M. Balzer]] of New York, a former watchmaker, constructed rotary engines in the 1890s.<ref>{{cite web|title=Balzer automobile patents|url=http://americanhistory.si.edu/onthemove/collection/object_1282.html|publisher=National Museum of American History|date=2016-11-02|access-date=2011-06-29|archive-date=2011-06-30|archive-url=https://web.archive.org/web/20110630214015/http://www.americanhistory.si.edu/onthemove/collection/object_1282.html|url-status=live}}</ref>  He was interested in the rotary layout for two main reasons:\n* To generate {{convert|100|hp|abbr=on}} at the low [[Revolutions per minute|rpm]] at which the engines of the day ran, the pulse resulting from each combustion stroke was quite large. To damp out these pulses, engines needed a large [[flywheel]], which added weight. In the rotary design the engine acted as its own flywheel, thus rotaries could be lighter than similarly sized conventional engines.\n* The cylinders had good cooling airflow over them, even when the aircraft was at rest\u2014which was important, as the low airspeed of aircraft of the time provided limited cooling airflow, and alloys of the day were less advanced. Balzer's early designs even dispensed with cooling fins, though subsequent rotaries did have this common feature of [[air cooling|air-cooled]] engines.\n\nBalzer produced a 3-cylinder, rotary engined car in 1894, then later became involved in [[Samuel Pierpont Langley|Langley]]'s ''Aerodrome'' attempts, which bankrupted him while he tried to make much larger versions of his engines. Balzer's rotary engine was later converted to static radial operation by Langley's assistant, [[Charles M. Manly]], creating the notable [[Manly-Balzer engine]].\n\n \nThe famous [[De Dion-Bouton]] company produced an experimental 4-cylinder rotary engine in 1899. Though intended for aviation use, it was not fitted to any aircraft.<ref name=nahum20/>\n\n {{main|Adams-Farwell}}\n\n[[File:Adams-Farwell Gyro Motor Rotary 5.jpg|thumb|right|An Adams-Farwell five cylinder rotary adapted for helicopter experimentation]]\nThe [[Adams-Farwell]] firm's automobiles, with the firm's first rolling prototypes using 3-cylinder rotary engines designed by Fay Oliver Farwell in 1898, led to production Adams-Farwell cars with first the 3-cylinder, then very shortly thereafter 5-cylinder rotary engines later in 1906, as another early American automaker utilizing rotary engines expressly manufactured for automotive use. [[Emil Berliner]] sponsored its development of the 5-cylinder Adams-Farwell rotary engine design concept as a lightweight power unit for his unsuccessful helicopter experiments. Adams-Farwell engines later powered fixed-wing aircraft in the US after 1910. It has also been asserted that the Gn\u00f4me design was derived from the Adams-Farwell, since an Adams-Farwell car is reported to have been demonstrated to the French Army in 1904. In contrast to the later Gn\u00f4me engines, and much like the later [[Clerget 9B]] and [[Bentley BR1]] aviation rotaries, the Adams-Farwell rotaries had conventional exhaust and inlet valves mounted in the cylinder heads.<ref name=nahum20/>\n\n [[File:Gnome-GA section.png|thumb|Sectional views of Gnome engine]]\nThe Gnome engine was the work of the three Seguin brothers, Louis, Laurent and Augustin. They were talented engineers and the grandsons of famous French engineer [[Marc Seguin]]. In 1906 the eldest brother, Louis, had formed the [[Gnome et Rh\u00f4ne|Soci\u00e9t\u00e9 des Moteurs Gnome]]<ref>{{cite web |title=SAFRAN |url=http://www.safran-group.com/site-safran/groupe/histoire/ |language=fr |quote=Le 6 juin 1905, Louis et Laurent Seguin fondent la soci\u00e9t\u00e9 des moteurs Gnome \u00e0 Gennevilliers |access-date=2009-09-14 |archive-date=2011-02-28 |archive-url=https://web.archive.org/web/20110228085617/http://www.safran-group.com/site-safran/groupe/histoire/ |url-status=live }}</ref><!-- for Gnome spelling see also: http://www.lincolnbeachey.com/gno2.jpg, http://en.wikipedia.org/wiki/File:Salon_de_locomotion_aerienne_1909_Grand_Palais_Paris.jpg, http://img.allposters.com/images/pic/VAS/0000-6164-4_b~Gnome-Rohne-Motorcycle-Posters.jpg--> to build [[stationary engine]]s for industrial use, having licensed production of the '''Gnom''' single-cylinder stationary engine from [[Motorenfabrik Oberursel]]\u2014who, in turn, built licensed Gnome engines for German aircraft during World War I.\n\nLouis was joined by his brother Laurent who designed a rotary engine specifically for aircraft use, using '''Gnom''' engine cylinders. The brothers' first experimental engine is said to have been a 5-cylinder model that developed {{convert|34|hp|abbr=on}}, and was a radial rather than rotary engine, but no photographs survive of the five-cylinder experimental model. The Seguin brothers then turned to rotary engines in the interests of better cooling, and the world's first production rotary engine, the 7-cylinder, air-cooled {{convert|50|hp|abbr=on}} "[[Gnome Omega|Omega]]" was shown at the 1908 Paris automobile show. The first Gnome Omega built still exists, and is now in the collection of the Smithsonian's [[National Air and Space Museum]].<ref>{{cite web|url=http://www.nasm.si.edu/collections/artifact.cfm?id=A19990069000|publisher=Smithsonian Institution|title=Gnome Omega No. 1 Rotary Engine|access-date=14 April 2012|archive-date=19 April 2012|archive-url=https://web.archive.org/web/20120419071116/http://www.nasm.si.edu/collections/artifact.cfm?id=A19990069000|url-status=live}}</ref> The Seguins used the highest strength material available - recently developed nickel steel alloy - and kept the weight down by machining components from solid metal, using the best American and German machine tools to create the engine's components; the cylinder wall of a 50 hp Gnome was only 1.5 mm (0.059 inches) thick, while the connecting rods were milled with deep central channels to reduce weight. While somewhat low powered in terms of units of power per litre, its power-to-weight ratio was an outstanding {{convert|1|hp|abbr=on}} per kg.\n\nThe following year, 1909, the inventor [[Roger Ravaud]] fitted one to his ''A\u00e9roscaphe'', a combination [[hydrofoil]]/aircraft, which he entered in the motor boat and aviation contests at Monaco. [[Henry Farman]]'s use of the Gnome at the famous Rheims aircraft meet that year brought it to prominence, when he won the Grand Prix for the greatest non-stop distance flown\u2014{{convert|180|km|mi}}\u2014and also set a world record for endurance flight.  The very first successful seaplane flight, of [[Henri Fabre]]'s ''[[Fabre Hydravion|Le Canard]]'', was powered by a Gnome Omega on March 28, 1910 near [[Marseille]].\n\nProduction of Gnome rotaries increased rapidly, with some 4,000 being produced before World War I, and Gnome also produced a two-row version (the 100 h.p. Double Omega), the larger 80 hp [[Gnome Lambda]]  and the 160 hp two-row Double Lambda. By the standards of other engines of the period, the Gnome was considered not particularly temperamental, and was credited as the first engine able to run for ten hours between overhauls.{{citation needed|date=April 2012}}\n\nIn 1913 the Seguin brothers introduced the new [[Monosoupape engine|Monosoupape]] ("single valve") series, which replaced inlet valves in the pistons by using a single valve in each cylinder head, which doubled as inlet and exhaust valve. The engine speed was controlled by varying the opening time and extent of the exhaust valves using levers acting on the valve tappet rollers, a system later abandoned due to valves burning. The weight of the Monosoupape was slightly less than the earlier two-valve engines, and it used less lubricating oil. The 100 hp Monosoupape was built with 9 cylinders, and developed its rated power at 1,200 rpm.<ref>{{cite book| last = Vivian| first = E. Charles| title = A History of Aeronautics| year = 2004| publisher = Kessinger Publishing| isbn = 1-4191-0156-0| pages = 255 }}</ref>  The later 160 hp nine-cylinder Gnome 9N rotary engine used the Monosoupape valve design while adding the safety factor of a [[dual ignition]] system, and was the last known rotary engine design to use such a cylinder head valving format. The 9N also featured an unusual ignition setup that allowed output values of one-half, one-quarter and one-eighth power levels to be achieved through use of the coupe-switch and a special five-position rotary switch that selected which of the trio of alternate power levels would be selected when the coupe-switch was depressed, allowing it to cut out all spark voltage to all nine cylinders, at evenly spaced intervals to achieve the multiple levels of power reduction.<ref>{{cite web |url=http://www.kozaero.com/look-at-the-gnocircme-9n-rotary-engine.html |title=(A) Look at the Gn\u00f4me 9N Rotary Engine |last1=Murrin |first1=Fred |last2=Phillips |first2=Terry |date= |website=kozaero.com |publisher=KozAero |access-date=August 13, 2021 |quote=In order to keep the engine running smoothly on reduced power settings, it was necessary for the selector switch to cut out all cylinders at evenly spaced intervals. It was also beneficial to have all cylinders firing periodically to keep them warm and to prevent the spark plugs from fouling with oil.  The selector switch has five positions, zero (0) for off and four running positions, one through four (1-4) (see Photo 5). The Gn\u00f4me 9N had two magnetos (and two spark plugs per cylinder) and the selector switch was wired to the right magneto only, so it was necessary for the pilot to turn off the left magneto if he wanted to change the speed of the engine. |archive-date=June 9, 2021 |archive-url=https://web.archive.org/web/20210609142716/http://www.kozaero.com/look-at-the-gnocircme-9n-rotary-engine.html |url-status=live }}</ref> The airworthy reproduction Fokker D.VIII parasol monoplane fighter at Old Rhinebeck Aerodrome, uniquely powered with a Gnome 9N, often demonstrates the use of its Gnome 9N's four-level output capability in both ground runs<ref>{{cite AV media |people= |date=August 4, 2019 |title=Old Rhinebeck Fokker D.VIII Startup and Takoff |medium=YouTube |language=English |url=https://www.youtube.com/watch?v=EzdjWP0-mnM |access-date=August 13, 2021 |url-status=live |archive-url=https://web.archive.org/web/20210813130952/https://www.youtube.com/watch?v=EzdjWP0-mnM |archive-date=2021-08-13 |format=YouTube |time=0:12 to 2:00  |location=Old Rhinebeck Aerodrome |publisher=Sholom |id= |isbn= |oclc= |quote= |ref=}}</ref> and in flight. \n[[File:Oberursel U.III.jpg|right|thumb|A German Oberursel U.III engine on museum display]]\nRotary engines produced by the [[Clerget]] and [[Le Rh\u00f4ne]] companies used conventional pushrod-operated valves in the cylinder head, but used the same principle of drawing the fuel mixture through the crankshaft, with the Le Rh\u00f4nes having prominent copper intake tubes running from the crankcase to the top of each cylinder to admit the intake charge.\n\nThe 80 hp (60 kW) seven-cylinder Gnome was the standard at the outbreak of World War I, as the Gnome Lambda, and it quickly found itself being used in a large number of aircraft designs. It was so good that it was licensed by a number of companies, including the German [[Motorenfabrik Oberursel]] firm who designed the original Gnom engine. Oberursel was later purchased by [[Fokker]], whose 80 hp Gnome Lambda copy was known as the Oberursel U.0. It was not at all uncommon for French Gn\u00f4me Lambdas, as used in the earliest examples of the [[Bristol Scout]] biplane, to meet German versions, powering [[Fokker E.I]] Eindeckers in combat, from the latter half of 1915 on.\n\nThe only attempts to produce twin-row rotary engines in any volume were undertaken by Gnome, with their Double Lambda fourteen-cylinder 160 hp design, and with the German Oberursel firm's early World War I clone of the Double Lambda design, the U.III of the same power rating.  While an example of the Double Lambda went on to power one of the Deperdussin Monocoque racing aircraft to a world-record speed of nearly 204 km/h (126 mph) in September 1913, the Oberursel U.III is only known to have been fitted into a few German production military aircraft, the [[Fokker E.IV]] fighter monoplane and [[Fokker D.III]] fighter biplane, both of whose failures to become successful combat types were partially due to the poor quality of the German powerplant, which was prone to wearing out after only a few hours of combat flight.\n\n [[File:Siemens-Halske Sh.III 07.jpg|thumb|right|A [[Siemens-Halske Sh.III]] preserved at the ''[[Technisches Museum Wien]]'' (Vienna Museum of Technology). This engine powered a number of German fighter aircraft types towards the end of World War I]]\nThe favourable [[power-to-weight ratio]] of the rotaries was their greatest advantage. While larger, heavier aircraft relied almost exclusively on conventional in-line engines, many fighter aircraft designers preferred rotaries right up to the end of the war.\n\nRotaries had a number of disadvantages, notably very high fuel consumption, partially because the engine was typically run at full throttle, and also because the valve timing was often less than ideal. Oil consumption was also very high. Due to primitive carburetion and absence of a true [[sump]], the lubricating oil was added to the fuel/air mixture. This made engine fumes heavy with smoke from partially burnt oil. [[Castor oil]] was the lubricant of choice, as its lubrication properties were unaffected by the presence of the fuel, and its gum-forming tendency was irrelevant in a total-loss lubrication system.  An unfortunate side-effect was that World War I pilots inhaled and swallowed a considerable amount of the oil during flight, leading to persistent [[diarrhoea]].<ref>{{cite book| author = Arthur Gould Lee| title = Open Cockpit: A Pilot of the Royal Flying Corps| year = 2012| publisher = Grub Street| isbn = 978-1-908117-25-0 }}</ref> Flying clothing worn by rotary engine pilots was routinely soaked with oil.\n\nThe rotating mass of the engine also made it, in effect, a large [[gyroscope]].  During level flight the effect was not especially apparent, but when turning the [[gyroscopic precession]] became noticeable. Due to the direction of the engine's rotation, left turns required effort and happened relatively slowly, combined with a tendency to nose up, while right turns were almost instantaneous, with a tendency for the nose to drop.<ref name="AEHS">{{cite web |url=http://www.enginehistory.org/Gnome%20Monosoupape.pdf |title=Gnome Monosoupape Type N Rotary |access-date=2008-05-01 |last=McCutcheon |first=Kimble D. |publisher=Aircraft Engine Historical Society |url-status=dead |archive-url=https://web.archive.org/web/20080706041104/http://www.enginehistory.org/Gnome%20Monosoupape.pdf |archive-date=2008-07-06 }}</ref>  In some aircraft, this could be advantageous in situations such as dogfights. The [[Sopwith Camel]] suffered to such an extent that it required left rudder for both left and right turns, and could be extremely hazardous if the pilot applied full power at the top of a loop at low airspeeds. Trainee Camel pilots were warned to attempt their first hard right turns only at altitudes above {{convert|1000|ft|abbr=on}}.<ref>{{cite book |author2=E. Eugene Larrabee |last=Abzug |first=Malcolm J. | title = Airplane Stability and Control|url=https://archive.org/details/airplanestabilit00abzu |url-access=limited | year = 2002| publisher = Cambridge University Press| isbn = 0-521-80992-4| pages = [https://archive.org/details/airplanestabilit00abzu/page/n30 9] }}</ref> The Camel's most famous German foe, the [[Fokker Dr.I]] [[triplane]], also used a rotary engine, usually the Oberursel Ur.II clone of the French-built [[Le Rhone 9J]] 110 hp powerplant.\n\nEven before the First World War, attempts were made to overcome the inertia problem of rotary engines. As early as 1906 [[Charles Benjamin Redrup]] had demonstrated to the [[Royal Flying Corps]] at [[Hendon]] a 'Reactionless' engine in which the [[crankshaft]] rotated in one direction and the cylinder block in the opposite direction, each one driving a propeller. A later development of this was the 1914 reactionless 'Hart' engine designed by Redrup in which there was only one propeller connected to the crankshaft, but it rotated in the opposite direction to the cylinder block, thereby largely cancelling out negative effects. This proved too complicated for reliable operation and Redrup changed the design to a static radial engine, which was later tried in the experimental [[Vickers F.B.12]]b and [[Vickers F.B.16|F.B.16]] aircraft,<ref>{{cite book| last = Fairney| first = William| title = The Knife and Fork Man - The Life and Works of Charles Benjamin Redrup| year = 2007| publisher = Diesel Publishing| isbn = 978-0-9554455-0-7 }}</ref> unfortunately without success.\n\nAs the war progressed, aircraft designers demanded ever-increasing amounts of power. Inline engines were able to meet this demand by improving their upper rev limits, which meant more power. Improvements in valve timing, ignition systems, and lightweight materials made these higher revs possible, and by the end of the war the average engine had increased from 1,200 rpm to 2,000. The rotary was not able to do the same due to the drag of the rotating cylinders through the air. For instance, if an early-war model of 1,200 rpm increased its revs to only 1,400, the drag on the cylinders increased 36%, as air drag increases with the square of velocity. At lower rpm, drag could simply be ignored, but as the rev count rose, the rotary was putting more and more power into spinning the engine, with less remaining to provide useful thrust through the propeller.\n[[File:Gegenl\u00e4ufer Umlaufmotor.gif|thumb|right|Animation of the Siemens-Halske Sh.III's internal operation]]\n\n One clever attempt to rescue the design, in a similar manner to Redrup's British "reactionless" engine concept, was made by [[Siemens AG]]. The crankcase (with the propeller still fastened directly to the front of it) and cylinders spun counterclockwise at 900 rpm, as seen externally from a "nose on" viewpoint, while the crankshaft (which unlike other designs, never "emerged" from the crankcase) and other internal parts spun clockwise at the same speed, so the set was effectively running at 1800 rpm. This was achieved by the use of bevel gearing at the rear of the crankcase, resulting in the eleven-cylindered [[Siemens-Halske Sh.III]], with less drag and less net torque.<ref name="Gray_Profile">{{cite book |last=Gray |first=Peter L. |title=Aircraft in Profile No.86 \u2014 The Siemens Schuckert D.III & IV |url=https://www.amazon.com/Aircraft-Profile-No-86-Schuckert/dp/B0007JXD1W |access-date=August 7, 2013 |year=1966 |publisher=Profile Publications, Ltd. |location=Leatherhead, Surrey, England |archive-date=July 4, 2013 |archive-url=https://web.archive.org/web/20130704200414/http://www.amazon.com/Aircraft-Profile-No-86-Schuckert/dp/B0007JXD1W |url-status=live }}</ref>{{rp|4-5}} Used on several late war types, notably the [[Siemens-Schuckert D.IV]] fighter, the new engine's low running speed, coupled with large, coarse pitched propellers that sometimes had four blades (as the SSW D.IV used), gave types powered by it outstanding rates of climb, with some examples of the late production Sh.IIIa powerplant even said to be delivering as much as 240 hp.<ref name="Gray_Profile" />{{rp|12}}\n\nOne new rotary powered aircraft, Fokker's own [[Fokker D.VIII|D.VIII]], was designed at least in part to provide some use for the Oberursel factory's backlog of otherwise redundant {{convert|110|hp|abbr=on}} [[Oberursel Ur.II|Ur.II]] engines, themselves clones of the [[Le Rh\u00f4ne 9J]] rotary.\n\nBecause of the Allied blockade of shipping, the Germans were increasingly unable to obtain the castor oil necessary to properly lubricate their rotary engines. Substitutes were never entirely satisfactory - causing increased running temperatures and reduced engine life.<ref>{{cite book| last = Guilmartin| first = John F. Jr.| title = Two Historians in Technology and War| year = 1994| publisher = United States Army War College, Strategic Studies Institute| isbn = 1428915222| page = 10| chapter = Technology and Strategy: What Are the Limits? }}</ref><ref>{{cite book| last = Fisher| first = Suzanne Hayes| title = The European Powers in the First World War: An Encyclopedia| year = 1999| publisher = Taylor & Francis| isbn = 081533351X| page = 10| chapter = Aircraft, production during the war| editor = Spencer C. Tucker |editor2=Laura Matysek Wood |editor3=Justin D. Murphy }}</ref><ref>{{cite book |title=Tariff Information Surveys on the Articles in Paragraphs 44 and 45 of the Tariff Act of 1913 |year=1921 |author=U.S. Tariff Commission |page=40 |publisher=Government Printing Office |location=Washington, D.C. }}</ref>\n\n \nBy the time the war ended, the rotary engine had become obsolete, and it disappeared from use quite quickly. The British [[Royal Air Force]] probably used rotary engines for longer than most other operators.  The RAF's standard post-war fighter, the [[Sopwith Snipe]], used the [[Bentley BR2]] rotary as the most powerful (at some {{convert|230|hp|abbr=on}}) rotary engine ever built by the [[Allies of World War I]].  The standard RAF training aircraft of the early post-war years, the 1914-origin [[Avro 504]]K, had a universal mounting to allow the use of several different types of low powered rotary, of which there was a large surplus supply. Similarly, the Swedish [[FVM \u00d61 Tummelisa]] advanced training aircraft, fitted with a Le-Rhone-Thulin {{convert|90|hp|abbr=on}} rotary engine, served until the mid thirties.\n\nDesigners had to balance the cheapness of war-surplus engines against their poor [[fuel efficiency]] and the operating expense of their total-loss lubrication system, and by the mid-1920s, rotaries had been more or less completely displaced even in British service, largely by the new generation of air-cooled "stationary" radials such as the [[Armstrong Siddeley Jaguar]] and [[Bristol Jupiter]].\n\nExperiments with the concept of the rotary engine continued.\n\nThe first version of the 1921 [[Michel engine]], an unusual opposed-piston [[cam engine]], used the principle of a rotary engine, in that its "cylinder block" rotated. This was soon replaced by a version with the same cylinders and cam, but with stationary cylinders and the cam track rotating in lieu of a crankshaft. A later version abandoned the cam altogether and used three coupled crankshafts.\n\nBy 1930 the Soviet helicopter pioneers, Boris N. Yuriev and Alexei M. Cheremukhin, both employed by ''[[TsAGI|Tsentralniy Aerogidrodinamicheskiy Institut]]'' (TsAGI, the Central Aerohydrodynamic Institute), constructed one of the first practical single-lift rotor machines with their TsAGI 1-EA single rotor helicopter, powered by two Soviet-designed and built M-2 rotary engines, themselves up-rated copies of the [[Gnome Monosoupape]] rotary engine of World War I. The TsAGI 1-EA set an unofficial altitude record of 605 meters (1,985 ft) with Cheremukhin piloting it on 14 August 1932 on the power of its twinned M-2 rotary engines.<ref>Savine, Alexandre. [http://www.ctrl-c.liu.se/misc/ram/1-ea.html "TsAGI 1-EA."] {{Webarchive|url=https://web.archive.org/web/20090126202112/http://www.ctrl-c.liu.se/misc/ram/1-ea.html |date=2009-01-26 }} ''ctrl-c.liu.se,'' 24 March 1997. Retrieved 12 December 2010.</ref>\n\nThe same-layout radial cylinder arrangement as the rotaries used, began to be used in true "stationary" [[radial engine]]s meant for aviation purposes as early as 1912; the first year that the Swiss engineers Georges Canton and Pierre Unne's [[Salmson water-cooled aero-engines|designs for liquid-cooled Salmson radial engines]] were built for test - by 1917, the Salmson 9Z water-cooled nine-cylinder radial engine design of some 250 CV output was powering Allied frontline combat aircraft, partly beginning the end of rotary engines for military aviation use."}},
{"article_title": "Restriction enzyme", "pageid": "26194", "revid": "1047337819", "timestamp": "2021-09-30T09:44:16Z", "history_paths": [["Restriction enzyme --- Introduction ---", "History"]], "categories": ["molecular biology", "biotechnology", "restriction enzymes", "ec 3.1", "life sciences industry"], "heading_tree": {"Restriction enzyme --- Introduction ---": {"History": {}, "Origins": {}, "Recognition site": {}, "Types": {"Type l": {}, "Type II": {}, "Type III": {}, "Type IV": {}, "Type V": {}, "Artificial restriction enzymes": {}}, "Nomenclature": {}, "Applications": {}, "Examples": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Restriction enzyme --- Introduction ---|History": "The term restriction enzyme originated from the studies of [[lambda phage|phage \u03bb]], a virus that infects bacteria, and the phenomenon of host-controlled restriction and modification of such bacterial phage or [[bacteriophage]].<ref>{{cite book |title=From Genes to Clones |author=Winnacker E-L |publisher=VCH |year=1987 |chapter=Chapter 2: Isolation, Identification, and Characterisation of DNA fragments |isbn=0-89573-614-4 |chapter-url=https://archive.org/details/fromgenestoclone0000winn }}</ref> The phenomenon was first identified in work done in the laboratories of [[Salvador Luria]], [[Jean Weigle]] and Giuseppe Bertani in the early 1950s.<ref name="Luria_Human_1952">{{cite journal | vauthors = Luria SE, Human ML | title = A nonhereditary, host-induced variation of bacterial viruses | journal = Journal of Bacteriology | volume = 64 | issue = 4 | pages = 557\u201369 | date = October 1952 | pmid = 12999684 | pmc = 169391 | doi = 10.1128/JB.64.4.557-569.1952 }}</ref><ref name="pmid13034700">{{cite journal | vauthors = Bertani G, Weigle JJ | title = Host controlled variation in bacterial viruses | journal = Journal of Bacteriology | volume = 65 | issue = 2 | pages = 113\u201321 | date = February 1953 | pmid = 13034700 | pmc = 169650 | doi = 10.1128/JB.65.2.113-121.1953 }}</ref>  It was found that, for a bacteriophage \u03bb that can grow well in one strain of ''Escherichia coli'', for example ''E. coli'' C, when grown in another strain, for example ''E. coli'' K, its yields can drop significantly, by as much as 3-5 orders of magnitude. The host cell, in this example ''E. coli'' K, is known as the restricting host and appears to have the ability to reduce the biological activity of the phage \u03bb. If a phage becomes established in one strain, the ability of that phage to grow also becomes restricted in other strains. In the 1960s, it was shown in work done in the laboratories of [[Werner Arber]] and [[Matthew Meselson]] that the restriction is caused by an enzymatic cleavage of the phage DNA, and the enzyme involved was therefore termed a restriction enzyme.<ref name="pmid4897066" /><ref name="pmid4868368">{{cite journal | vauthors = Meselson M, Yuan R | title = DNA restriction enzyme from E. coli | journal = Nature | volume = 217 | issue = 5134 | pages = 1110\u20134 | date = March 1968 | pmid = 4868368 | doi = 10.1038/2171110a0 | bibcode = 1968Natur.217.1110M | s2cid = 4172829 }}</ref><ref name="pmid13888713">{{cite journal | vauthors = Dussoix D, Arber W | title = Host specificity of DNA produced by Escherichia coli. II. Control over acceptance of DNA from infecting phage lambda | journal = Journal of Molecular Biology | volume = 5 | issue = 1 | pages = 37\u201349 | date = July 1962 | pmid = 13888713 | doi = 10.1016/S0022-2836(62)80059-X }}</ref><ref name="pmid14187389">{{cite journal | vauthors = Lederberg S, Meselson M | title = Degradation of non-replicating bacteriophage dna in non-accepting cells | journal = Journal of Molecular Biology | volume = 8 | issue = 5 | pages = 623\u20138 | date = May 1964 | pmid = 14187389 | doi = 10.1016/S0022-2836(64)80112-1 }}</ref>\n\nThe restriction enzymes studied by Arber and Meselson were type I restriction enzymes, which cleave DNA randomly away from the recognition site.<ref name="pmid15840723">{{cite journal | vauthors = Roberts RJ | title = How restriction enzymes became the workhorses of molecular biology | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 102 | issue = 17 | pages = 5905\u20138 | date = April 2005 | pmid = 15840723 | pmc = 1087929 | doi = 10.1073/pnas.0500923102 | bibcode = 2005PNAS..102.5905R | doi-access = free }}</ref> In 1970, [[Hamilton O. Smith]], [[Thomas J. Kelly (scientist)|Thomas Kelly]] and Kent Wilcox isolated and characterized the first type II restriction enzyme, [[HindII|''Hind''II]], from the bacterium ''[[Haemophilus influenzae]]''.<ref name="pmid5312500">{{cite journal | vauthors = Smith HO, Wilcox KW | title = A restriction enzyme from Hemophilus influenzae. I. Purification and general properties | journal = Journal of Molecular Biology | volume = 51 | issue = 2 | pages = 379\u201391 | date = July 1970 | pmid = 5312500 | doi = 10.1016/0022-2836(70)90149-X }}</ref><ref name="pmid5312501">{{cite journal | vauthors = Kelly TJ, Smith HO | title = A restriction enzyme from Hemophilus influenzae. II | journal = Journal of Molecular Biology | volume = 51 | issue = 2 | pages = 393\u2013409 | date = July 1970 | pmid = 5312501 | doi = 10.1016/0022-2836(70)90150-6 }}</ref> Restriction enzymes of this type are more useful for laboratory work as they cleave DNA at the site of their recognition sequence and are the most commonly used as a molecular biology tool.<ref>{{cite journal | vauthors = Loenen WA, Dryden DT, Raleigh EA, Wilson GG, Murray NE | title = Highlights of the DNA cutters: a short history of the restriction enzymes | journal = Nucleic Acids Research | volume = 42 | issue = 1 | pages = 3\u201319 | date = January 2014 | pmid = 24141096 | pmc = 3874209 | doi = 10.1093/nar/gkt990 }}</ref> Later, [[Daniel Nathans]] and Kathleen Danna showed that cleavage of [[simian virus 40]] (SV40) DNA by restriction enzymes yields specific fragments that can be separated using [[polyacrylamide gel electrophoresis]], thus showing that restriction enzymes can also be used for mapping DNA.<ref name="pmid4332003">{{cite journal | vauthors = Danna K, Nathans D | title = Specific cleavage of simian virus 40 DNA by restriction endonuclease of Hemophilus influenzae | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 68 | issue = 12 | pages = 2913\u20137 | date = December 1971 | pmid = 4332003 | pmc = 389558 | doi = 10.1073/pnas.68.12.2913 | bibcode = 1971PNAS...68.2913D | doi-access = free }}</ref> For their work in the discovery and characterization of restriction enzymes, the 1978 [[Nobel Prize for Physiology or Medicine]] was awarded to [[Werner Arber]], [[Daniel Nathans]], and [[Hamilton O. Smith]].<ref name="urlMedicine 1978">{{cite web | url = http://nobelprize.org/nobel_prizes/medicine/laureates/1978/ | title = The Nobel Prize in Physiology or Medicine | year = 1978 | publisher = The Nobel Foundation | quote = for the discovery of restriction enzymes and their application to problems of molecular genetics | access-date = 2008-06-07}}</ref> The discovery of restriction enzymes allows DNA to be manipulated, leading to the development of [[recombinant DNA]] technology that has many applications, for example, allowing the large scale production of proteins such as human [[insulin]] used by [[diabetes|diabetic]] patients.<ref name="Luria_Human_1952"/><ref name="pmid358198">{{cite journal | vauthors = Villa-Komaroff L, Efstratiadis A, Broome S, Lomedico P, Tizard R, Naber SP, Chick WL, Gilbert W | display-authors = 6 | title = A bacterial clone synthesizing proinsulin | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 75 | issue = 8 | pages = 3727\u201331 | date = August 1978 | pmid = 358198 | pmc = 392859 | doi = 10.1073/pnas.75.8.3727 | bibcode = 1978PNAS...75.3727V | doi-access = free }}</ref>"}},
{"article_title": "Superconductivity", "pageid": "26884", "revid": "1055345720", "timestamp": "2021-11-15T09:42:25Z", "history_paths": [["Superconductivity --- Introduction ---", "History of superconductivity"]], "categories": ["superconductivity", "phases of matter", "exotic matter", "unsolved problems in physics", "magnetic levitation", "physical phenomena", "spintronics", "phase transitions", "articles containing video clips", "science and technology in the netherlands", "dutch inventions", "1911 in science"], "heading_tree": {"Superconductivity --- Introduction ---": {"Classification": {"Response to a magnetic field": {}, "By theory of operation": {}, "By critical temperature": {}, "By material": {}}, "Elementary properties of superconductors": {"Zero electrical DC resistance": {}, "Phase transition {{anchor|Superconducting phase transition}}": {}, "Meissner effect": {}, "London moment": {}}, "History of superconductivity": {"London constitutive equations": {}, "Conventional theories (1950s)": {}, "Further history": {}}, "High-temperature superconductivity": {}, "Applications": {}, "Nobel Prizes for superconductivity": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Superconductivity --- Introduction ---|History of superconductivity": "[[File:Ehrenfest Lorentz Bohr Kamerlingh Onnes.jpg|thumb|Heike Kamerlingh Onnes (right), the discoverer of superconductivity.  [[Paul Ehrenfest]], [[Hendrik Lorentz]], [[Niels Bohr]] stand to his left.]]\n{{Main|History of superconductivity}}\n\nSuperconductivity was discovered on April 8, 1911 by [[Heike Kamerlingh Onnes]], who was studying the resistance of solid [[mercury (element)|mercury]] at [[cryogenic]] temperatures using the recently produced [[liquid helium]] as a [[refrigerant]].<ref>{{Cite journal|last1=van Delft|first1=Dirk|last2=Kes|first2=Peter|date=2010-09-01|title=The discovery of superconductivity|url=https://physicstoday.scitation.org/doi/10.1063/1.3490499|journal=[[Physics Today]]|volume=63|issue=9|pages=38\u201343|doi=10.1063/1.3490499|bibcode=2010PhT....63i..38V|issn=0031-9228}}</ref> At the temperature of 4.2 K, he observed that the resistance abruptly disappeared.<ref>{{cite journal\n |last1=Kamerlingh Onnes\n |first1=Heike\n |title=Further experiments with liquid helium. C. On the change of electric resistance of pure metals at very low temperatures etc. IV. The resistance of pure mercury at helium temperatures\n |journal=Proceedings of the Section of Sciences\n |date=1911\n |volume=13\n |pages=1274\u20131276\n |url=http://www.dwc.knaw.nl/toegangen/digital-library-knaw/?pagetype=publDetail&pId=PU00013358&lang=en|bibcode=1910KNAB...13.1274K\n }}</ref> In the same experiment, he also observed the [[superfluid]] transition of helium at 2.2 K, without recognizing its significance. The precise date and circumstances of the discovery were only reconstructed a century later, when Onnes's notebook was found.<ref>{{cite journal |author=Dirk vanDelft |author2=Peter Kes |date=September 2010 |journal=Physics Today |url=http://ilorentz.org/history/cold/DelftKes_HKO_PT.pdf |title=The Discovery of Superconductivity |doi=10.1063/1.3490499 |volume=63 |issue=9 |pages=38\u201343 |bibcode=2010PhT....63i..38V}}</ref> In subsequent decades, superconductivity was observed in several other materials. In 1913, [[lead]] was found to superconduct at 7 K, and in 1941 [[niobium nitride]] was found to superconduct at 16 K.\n\nGreat efforts have been devoted to finding out how and why superconductivity works; the important step occurred in 1933, when [[Walther Meissner|Meissner]] and [[Robert Ochsenfeld|Ochsenfeld]] discovered that superconductors expelled applied magnetic fields, a phenomenon which has come to be known as the [[Meissner effect]].<ref name=MeissnerOchsenfeld>{{cite journal\n |author = W. Meissner\n |author2 = R. Ochsenfeld\n |name-list-style = amp\n |date = 1933\n |title = Ein neuer Effekt bei Eintritt der Supraleitf\u00e4higkeit\n |journal = [[Naturwissenschaften]]\n |volume = 21 |issue = 44 |pages = 787\u2013788\n |doi = 10.1007/BF01504252\n|bibcode = 1933NW.....21..787M |s2cid = 37842752\n }}</ref> In 1935, [[Fritz London|Fritz]] and [[Heinz London]] showed that the Meissner effect was a consequence of the minimization of the electromagnetic [[thermodynamic free energy|free energy]] carried by superconducting current.<ref>{{cite journal\n |author = F. London\n |author2 = H. London\n |name-list-style = amp\n |date = 1935\n |title = The Electromagnetic Equations of the Supraconductor\n |journal = [[Proceedings of the Royal Society of London A]]\n |volume = 149 |issue = 866 |pages = 71\u201388\n |doi = 10.1098/rspa.1935.0048\n |jstor=96265\n|bibcode = 1935RSPSA.149...71L |doi-access = free\n }}</ref>\n\n The theoretical model that was first conceived for superconductivity was completely classical: it is summarized by [[London equations|London constitutive equations]]. \nIt was put forward by the brothers Fritz and Heinz London in 1935, shortly after the discovery that magnetic fields are expelled from superconductors. A major triumph of the equations of this theory is their ability to explain the [[Meissner effect]],<ref name=MeissnerOchsenfeld /> wherein a material exponentially expels all internal magnetic fields as it crosses the superconducting threshold. By using the London equation, one can obtain the dependence of the magnetic field inside the superconductor on the distance to the surface.<ref>{{cite web\n|url = http://openlearn.open.ac.uk/mod/oucontent/view.php?id=398540&section=3.3\n|title = The London equations\n|publisher = The Open University\n|access-date  = 2011-10-16}}</ref>\n\nThe two constitutive equations for a superconductor by London are:\n:<math>\\frac{\\partial \\mathbf{j}}{\\partial t} = \\frac{n e^2}{m}\\mathbf{E}, \\qquad \\mathbf{\\nabla}\\times\\mathbf{j} =-\\frac{n e^2}{m}\\mathbf{B}. </math>\nThe first equation follows from [[Newton's second law]] for superconducting electrons.\n\n During the 1950s, theoretical [[condensed matter physics|condensed matter]] physicists arrived at an understanding of "conventional" superconductivity, through a pair of remarkable and important theories: the phenomenological [[Ginzburg\u2013Landau theory]] (1950) and the microscopic [[BCS theory]] (1957).<ref>{{cite journal\n |author = J. Bardeen\n |author2 = L. N. Cooper\n |author3 = J. R. Schrieffer\n |name-list-style = amp\n |date = 1957\n |title = Microscopic Theory of Superconductivity\n |journal = [[Physical Review]]\n |volume = 106 |issue = 1 |pages = 162\u2013164\n |doi = 10.1103/PhysRev.106.162\n|bibcode = 1957PhRv..106..162B |doi-access = free\n }}</ref><ref name=BardeenCooperSchrieffer>{{cite journal\n |author = J. Bardeen\n |author2 = L. N. Cooper\n |author3 = J. R. Schrieffer\n |name-list-style = amp\n |date = 1957\n |title = Theory of Superconductivity\n |journal = [[Physical Review]]\n |volume = 108 |issue = 5 |pages = 1175\u20131205\n |doi = 10.1103/PhysRev.108.1175|bibcode = 1957PhRv..108.1175B |doi-access = free\n }}</ref>\n\nIn 1950, the [[Phenomenology (particle physics)|phenomenological]] [[Ginzburg\u2013Landau theory]] of superconductivity was devised by [[Lev Landau|Landau]] and [[Vitaly Ginzburg|Ginzburg]].<ref>{{cite journal\n |author = V. L. Ginzburg\n |author2 = L.D. Landau\n |name-list-style = amp\n |date = 1950\n |title = On the theory of superconductivity\n |journal = [[Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki]]\n |volume = 20 |page = 1064\n}}</ref> This theory, which combined Landau's theory of second-order [[phase transition]]s with a [[Schr\u00f6dinger equation|Schr\u00f6dinger]]-like wave equation, had great success in explaining the macroscopic properties of superconductors. In particular, [[Alexei Alexeyevich Abrikosov|Abrikosov]] showed that Ginzburg\u2013Landau theory predicts the division of superconductors into the two categories now referred to as Type I and Type II. Abrikosov and Ginzburg were awarded the 2003 Nobel Prize for their work (Landau had received the 1962 Nobel Prize for other work, and died in 1968). The four-dimensional extension of the Ginzburg\u2013Landau theory, the [[Coleman\u2013Weinberg potential|Coleman-Weinberg model]], is important in [[quantum field theory]] and [[cosmology]].\n\nAlso in 1950, Maxwell and Reynolds ''et al.'' found that the critical temperature of a superconductor depends on the [[isotope|isotopic mass]] of the constituent [[chemical element|element]].<ref>{{cite journal\n |author = E. Maxwell\n |date = 1950\n |title = Isotope Effect in the Superconductivity of Mercury\n |journal = [[Physical Review]]\n |volume = 78 |issue = 4 |page = 477\n |doi =10.1103/PhysRev.78.477\n|bibcode = 1950PhRv...78..477M }}</ref><ref>{{cite journal\n |author = C. A. Reynolds\n |author2 = B. Serin\n |author3 = W. H. Wright\n |author4 = L. B. Nesbitt\n |name-list-style = amp\n |date = 1950\n |title = Superconductivity of Isotopes of Mercury\n |journal = [[Physical Review]]\n |volume = 78 |issue = 4 |page = 487\n |doi = 10.1103/PhysRev.78.487\n|bibcode = 1950PhRv...78..487R }}</ref> This important discovery pointed to the [[electron]]-[[phonon]] interaction as the microscopic mechanism responsible for superconductivity.\n\nThe complete microscopic theory of superconductivity was finally proposed in 1957 by [[John Bardeen|Bardeen]], [[Leon Neil Cooper|Cooper]] and [[John Robert Schrieffer|Schrieffer]].<ref name=BardeenCooperSchrieffer /> This BCS theory explained the superconducting current as a [[superfluid]] of [[Cooper pair]]s, pairs of electrons interacting through the exchange of phonons. For this work, the authors were awarded the Nobel Prize in 1972.\n\nThe BCS theory was set on a firmer footing in 1958, when [[N. N. Bogolyubov]] showed that the BCS wavefunction, which had originally been derived from a variational argument, could be obtained using a canonical transformation of the electronic [[Hamiltonian (quantum mechanics)|Hamiltonian]].<ref>{{cite journal\n |author = N. N. Bogoliubov\n |date = 1958\n |title = A new method in the theory of superconductivity\n |journal = [[Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki]]\n |volume = 34 |page = 58\n}}</ref> In 1959, [[Lev Gor'kov]] showed that the BCS theory reduced to the Ginzburg\u2013Landau theory close to the critical temperature.<ref>{{cite journal\n |author = L. P. Gor'kov\n |date = 1959\n |title = Microscopic derivation of the Ginzburg\u2014Landau equations in the theory of superconductivity\n |journal = [[Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki]]\n |volume = 36 |page = 1364\n}}</ref><ref name=BCS-boboliubov>{{cite journal |author=M. Combescot |author2=W.V. Pogosov |author3=O. Betbeder-Matibet|title=BCS ansatz for superconductivity in the light of the Bogoliubov approach and the Richardson\u2013Gaudin exact wave function|journal=Physica C: Superconductivity|date=2013|volume=485|pages=47\u201357|doi=10.1016/j.physc.2012.10.011|arxiv=1111.4781|bibcode = 2013PhyC..485...47C }}</ref>\n\nGeneralizations of BCS theory for conventional superconductors form the basis for the understanding of the phenomenon of [[superfluidity]], because they fall into the [[lambda transition]] universality class. The extent to which such generalizations can be applied to [[unconventional superconductor]]s is still controversial.\n\n The first practical application of superconductivity was developed in 1954 with [[Dudley Allen Buck]]'s invention of the [[cryotron]].<ref name=mit-memo>{{cite web|last1=Buck|first1=Dudley A.|title=The Cryotron \u2013 A Superconductive Computer Component|url=http://dome.mit.edu/bitstream/handle/1721.3/40618/MC665_r15_M-3843.pdf|publisher=Lincoln Laboratory, Massachusetts Institute of Technology|access-date=10 August 2014}}</ref> Two superconductors with greatly different values of the critical magnetic field are combined to produce a fast, simple switch for computer elements.\n\nSoon after discovering superconductivity in 1911, Kamerlingh Onnes attempted to make an electromagnet with superconducting windings but found that relatively low magnetic fields destroyed superconductivity in the materials he investigated. Much later, in 1955, G. B. Yntema <ref>{{cite journal\n  | author = G.B.Yntema\n  | date = 1955\n  | title = Superconducting Winding for Electromagnet\n  | journal = [[Physical Review]]\n  | volume = 98\n  | issue = 4\n  | page = 1197\n  | doi =  10.1103/PhysRev.98.1144|bibcode = 1955PhRv...98.1144. }}</ref>  succeeded in constructing a small 0.7-tesla iron-core electromagnet with superconducting niobium wire windings. Then, in 1961, J. E. Kunzler, E. Buehler, F. S. L. Hsu, and J. H. Wernick <ref>{{cite journal\n  |author=J. E. Kunzler |author2=E. Buehler |author3=F. L. S. Hsu |author4=J. H. Wernick\n  | date = 1961\n  | title = Superconductivity in Nb3Sn at High Current Density in a Magnetic Field of 88 kgauss\n  | journal = Physical Review Letters\n  | volume = 6\n  | issue = 3\n  | pages = 89\u201391\n  | doi = 10.1103/PhysRevLett.6.89|bibcode = 1961PhRvL...6...89K }}</ref> made the startling discovery that, at 4.2 kelvin [[niobium\u2013tin]], a compound consisting of three parts niobium and one part tin, was capable of supporting a current density of more than 100,000 amperes per square centimeter in a magnetic field of 8.8 tesla. Despite being brittle and difficult to fabricate, niobium\u2013tin has since proved extremely useful in supermagnets generating magnetic fields as high as 20 tesla. In 1962 T. G. Berlincourt and R. R. Hake <ref>{{cite journal\n  | author = T. G. Berlincourt and R. R. Hake\n  | date = 1962\n  | title = Pulsed-Magnetic-Field Studies of Superconducting Transition Metal Alloys at High and Low Current Densities\n  | journal = Bulletin of the American Physical Society\n  | volume = II-7\n  | page = 408}}</ref><ref>{{cite journal\n  | author = T. G. Berlincourt\n  | date = 1987\n  | title = Emergence of Nb-Ti as Supermagnet Material\n  | journal = Cryogenics\n  | volume = 27\n  | issue = 6\n  | pages = 283\u2013289\n  | doi = 10.1016/0011-2275(87)90057-9|bibcode = 1987Cryo...27..283B\n  | url=http://fs.magnet.fsu.edu/~lee/superconductor-history_files/Centennial_Supplemental/11_2_Nb-Ti_from_beginnings_to_perfection-fullreferences.pdf}}</ref> discovered that more ductile alloys of niobium and titanium are suitable for applications up to 10 tesla.\nPromptly thereafter, commercial production of [[niobium\u2013titanium]] supermagnet wire commenced at [[Westinghouse Electric Corporation]] and at [[Wah Chang Corporation]]. Although niobium\u2013titanium boasts less-impressive superconducting properties than those of niobium\u2013tin, niobium\u2013titanium has, nevertheless, become the most widely used "workhorse" supermagnet material, in large measure a consequence of its very high [[ductility]] and ease of fabrication. However, both niobium\u2013tin and niobium\u2013titanium find wide application in MRI medical imagers, bending and focusing magnets for enormous high-energy-particle accelerators, and a host of other applications. Conectus, a European superconductivity consortium, estimated that in 2014, global economic activity for which superconductivity was indispensable amounted to about five billion euros, with MRI systems accounting for about 80% of that total.\n\nIn 1962, [[Brian David Josephson|Josephson]] made the important theoretical prediction that a supercurrent can flow between two pieces of superconductor separated by a thin layer of insulator.<ref>{{cite journal\n |author = B. D. Josephson\n |date = 1962\n |title = Possible new effects in superconductive tunnelling\n |journal = [[Physics Letters]]\n |volume = 1 |issue=7 |pages = 251\u2013253\n |doi = 10.1016/0031-9163(62)91369-0\n|bibcode = 1962PhL.....1..251J }}</ref> This phenomenon, now called the [[Josephson effect]], is exploited by superconducting devices such as [[SQUID]]s. It is used in the most accurate available measurements of the [[magnetic flux quantum]] ''\u03a6''<sub>0</sub> = ''h''/(2''e''), where ''h'' is the [[Planck constant]]. Coupled with the [[quantum Hall effect|quantum Hall resistivity]], this leads to a precise measurement of the Planck constant. Josephson was awarded the Nobel Prize for this work in 1973.<ref>{{Cite web|title=The Nobel Prize in Physics 1973|url=https://www.nobelprize.org/prizes/physics/1973/summary/|url-status=live|access-date=2021-03-30|website=[[Nobel Foundation|NobelPrize.org]]|language=en-US}}</ref>\n\nIn 2008, it was proposed that the same mechanism that produces superconductivity could produce a [[superinsulator]] state in some materials, with almost infinite [[electrical resistance]].<ref>{{cite web\n | title = Newly discovered fundamental state of matter, a superinsulator, has been created.\n | website = Science Daily\n | date = April 9, 2008\n | url = https://www.sciencedaily.com/releases/2008/04/080408160614.htm\n | access-date = 2008-10-23\n}}</ref> The first development and study of superconducting [[Bose\u2013Einstein condensate]] (BEC) in 2020 suggests that there is a "smooth transition between" BEC and [[BCS theory|Bardeen-Cooper-Shrieffer]] regimes.<ref>{{cite news |title=Researchers demonstrate a superconductor previously thought impossible |url=https://phys.org/news/2020-11-superconductor-previously-thought-impossible.html |access-date=8 December 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Hashimoto |first1=Takahiro |last2=Ota |first2=Yuichi |last3=Tsuzuki |first3=Akihiro |last4=Nagashima |first4=Tsubaki |last5=Fukushima |first5=Akiko |last6=Kasahara |first6=Shigeru |last7=Matsuda |first7=Yuji |last8=Matsuura |first8=Kohei |last9=Mizukami |first9=Yuta |last10=Shibauchi |first10=Takasada |last11=Shin |first11=Shik |last12=Okazaki |first12=Kozo |title=Bose\u2013Einstein condensation superconductivity induced by disappearance of the nematic state |journal=Science Advances |date=1 November 2020 |volume=6 |issue=45 |pages=eabb9052 |doi=10.1126/sciadv.abb9052 |pmid=33158862 |pmc=7673702 |bibcode=2020SciA....6.9052H |url=|language=en |issn=2375-2548}}</ref>"}},
{"article_title": "Split screen (video production)", "pageid": "27487", "revid": "1052150986", "timestamp": "2021-10-27T17:30:25Z", "history_paths": [["Split screen (video production) --- Introduction ---", "Popularisation"], ["Split screen (video production) --- Introduction ---", "Influences"], ["Split screen (video production) --- Introduction ---", "Usage"], ["Split screen (video production) --- Introduction ---", "Notable uses of split screen"]], "categories": ["cinematic techniques", "film and video technology", "film and video terminology", "special effects"], "heading_tree": {"Split screen (video production) --- Introduction ---": {"Popularisation": {}, "Influences": {}, "Digital technology": {}, "Usage": {"In films": {}, "By filmmakers": {}, "In technology": {}, "In music video": {}, "In television": {}}, "Notable uses of split screen": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Split screen (video production) --- Introduction ---|Popularisation": "Several studio-made films in the 1960s popularized the use of split screen. They include [[Indiscreet (1958 film)|''Indiscreet'']] (1958), [[John Frankenheimer]]'s ''[[Grand Prix (1966 film)|Grand Prix]]'' (1966), [[Richard Fleischer]]'s ''[[The Boston Strangler (film)|The Boston Strangler]]'' (1968), [[Norman Jewison]]'s ''[[The Thomas Crown Affair (1968 film)|The Thomas Crown Affair]]'' (1968), ''[[Airport (1970 film)|Airport]]'' (1970), ''[[Woodstock (film)|Woodstock]]'' (1970), ''[[The Andromeda Strain (film)|The Andromeda Strain]]'' (1971), ''[[Sisters (1973 film)|Sisters]]'' (1972), ''[[Carrie (1976 film)|Carrie]]'' (1976) and ''[[More American Graffiti]]'' (1979).\n\nIn ''[[Indiscreet (1958 film)|Indiscreet]]'', the technique was famously used to bypass the censors and allow [[Cary Grant]] and [[Ingrid Bergman]] to be in bed together, and even to appear to pat her on the bottom.<ref>{{cite book | last=Glitre  | first=Kathrina | date=October 31, 2006 | page=196 | location=Manchester | publisher=[[Manchester University Press]] | title=Hollywood Romantic Comedy: States of the Union, 1934-1965 | url=https://books.google.com/books?id=Hb5rBgAAQBAJ&pg=PT196 | access-date=April 9, 2018 | isbn=0-719-07078-3 }}</ref>", "Split screen (video production) --- Introduction ---|Influences": "An influential arena for the great split screen movies of the 1960s were two [[world's fair]]s - the [[1964 New York World's Fair]], where [[Ray and Charles Eames]] had a 17-screen film they created for IBM's "Think" Pavilion (it included sections with race car driving) and the 3-division film ''[[To Be Alive!|To Be Alive]],'' by [[Francis Thompson]], which won the Academy Award that year for Best Short.  [[John Frankenheimer]] made ''Grand Prix'' after his visit to the [[1964 New York World's Fair]]. The success of these pavilions further influenced the 1967 [[Universal exhibition]] in Montreal, commonly referred to as [[Expo 67]], where multi-screen highlights included ''[[In the Labyrinth (film)|In the Labyrinth]]'', hailed by ''[[Time (magazine)|Time]]'' magazine as a "stunning visual display," their review concluding: "such visual delights as Labyrinth ... suggest that cinema\u2014the most typical of 20th century arts\u2014has just begun to explore its boundaries and possibilities," as well as ''[[A Place to Stand (film)|A Place to Stand]]'', which displayed [[Christopher Chapman]]'s pioneering [[Multi-Dynamic Image Technique|"multi-dynamic image technique"]] of shifting multiple images. Directors [[Norman Jewison]]  and [[Richard Fleischer]] conceived their ambitious split-screen films of 1968 after visiting Expo '67.<ref>[https://web.archive.org/web/20070516215313/http://www.time.com/time/magazine/article/0,9171,899606-2,00.html "Cinema: Magic in Montreal: The Films of Expo"]. ''[[Time (magazine)|Time]]''. July 07, 1967. Retrieved 2012-01-14.</ref>\n\nIt's also common to use this technique to simultaneously portray both participants in a telephone conversation, a long-standing convention which dates back to early silents, as in  [[Lois Weber]]'s triangular frames in her 1913 ''Suspense'', and culminating in ''[[Pillow Talk (film)|Pillow Talk]]'', where [[Doris Day]] and [[Rock Hudson]] share a party line.  So linked to this convention are the [[Doris Day]]/[[Rock Hudson]] movies that ''[[Down With Love]]'', the only slightly tongue-in-cheek homage, used split screen in several phone calls, explicitly parodying this use. In the 1971 Emmy Award-winning TV movie "Brian's Song" which portrays the story of former Chicago Bears running backs Brian Piccolo and Hall of Famer Gale Sayers, it's the night after Piccolo's second surgery and Piccolo (James Caan) is talking to Sayers (Billy Dee Williams) on the phone. There is a diagonal split screen from upper left corner to lower right corner (Piccolo on the right side and Sayers on the left). The [[BBC]] series ''[[Coupling (UK TV series)|Coupling]]'' made extensive use of split screen as one of several techniques that are unconventional for TV series, often to a humorous effect. One episode, 'Split', was even named after the use of the effect. The acclaimed Fox TV series ''[[24 (TV series)|24]]'' used split-screen extensively to depict the many simultaneous events, enhancing the show's real-time element as well as connecting its multiple storylines.\n\nAn unusual and revolutionary use of split screen as an extension to the cinematic vocabulary was invented by film director [[Roger Avary]] in ''[[The Rules of Attraction (film)|The Rules of Attraction]]'' (2002) where two separate halves of a split screen are folded together into one seamless shot through the use of [[motion control photography]]. The much acclaimed shot was examined and detailed in Bravo Television's ''Anatomy of a Scene''.", "Split screen (video production) --- Introduction ---|Usage": "Early use of split screen can be seen in [[Lois Weber]] and [[Phillips Smalley]]\u2019s ''[[Suspense (1913 film)|Suspense]]'' (1913), where it is used to portray simultaneous actions, and in [[Yakov Protazanov]]\u2019s ''[[The Queen of Spades (1916 film)|The Queen of Spades]]'' (1916), where one screen depicts reality and the other a character's inner desires.<ref>{{Cite web|url=https://www.bfi.org.uk/films-tv-people/4ce2b6b313a76|title=PIKOVAYA DAMA (1916)|website=BFI}}</ref> This technique has been used to portray twins in such films as ''[[Wonder Man (film)|Wonder Man]]'' (1945), ''[[The Dark Mirror (1946 film)|The Dark Mirror]]'' (1946), ''The Parent Trap'' (both [[The Parent Trap (1961 film)|the 1961 original]] and [[The Parent Trap (1998 film)|the 1998 remake]]), and ''[[Adaptation (film)|Adaptation]]'' (2002). In the 1961 version of ''The Parent Trap'', conversations between the twins were simulated by filming the actress ([[Hayley Mills]]) as she stood at the left of the frame facing right, then filming her again, standing at the right and facing left. The negative of the first action was placed into a printer and copied onto another negative, the composite, but this other negative was masked so that only the right part of the original picture is copied. Then the composite was rewound and the negative of the second action was copied onto the right side of each frame. On this second pass, the left side was masked to prevent double exposure. This technique is then carefully hidden by background lines, such as windows, doors, etc. to disguise the split.\n\n[[Hans Canosa]]'s 2005 film ''[[Conversations with Other Women]]'' made extensive use of split screens. ''Conversations'' juxtaposed shot and reverse shot of two actors in the same take, captured with two cameras, for the entire movie. The film was designed to enlist the audience as perceptual editors, as they can choose to watch either character act and react in real time. While the shot/reverse shot function of split screen comprises most of the running time of the film, the filmmakers also used split screen for other spatial, temporal and emotional effects. ''Conversations''' split screen sometimes showed flashbacks of the recent or distant past juxtaposed with the present; moments imagined or hoped by the characters juxtaposed with present reality; present experience fractured into more than one emotion for a given line or action, showing an actor performing the same moment in different ways; and present and near future actions juxtaposed to accelerate the narrative in temporal overlap.\n\n The visionary French director, [[Abel Gance]], used the term "[[Polyvision]]" to describe his three-camera, three-projector technique for both widening and dividing the screen in his 1927 silent epic, ''[[Napol\u00e9on (1927 film)|Napol\u00e9on]]''. The filmmaker [[Brian De Palma]] has incorporated split screens into many of his films, most notably in ''[[Sisters (1973 film)|Sisters]]'' (1973) and they have since become synonymous with his filmmaking style (Specifically 1981's ''Blow Out'' and 1998's ''Snake Eyes'').\n\n The "Interactive Olaf" bonus feature from the [[DVD]] release of ''[[Lemony Snicket's A Series of Unfortunate Events]]'' shows [[Jim Carrey]]'s makeup tests from the movie in a four-way split-screen. Viewers can split the audio by selecting which one to listen to, then pressing "ENTER" on their DVD remote. The split screen has also been simulated in video games, most notably ''[[Fahrenheit (2005 video game)|Fahrenheit]]'' where it is used to allow a player to keep track of multiple simultaneous elements relevant to the gameplay.\n\n A number of music videos have made creative use of split screen presentations. In [[Michael Jackson]]'s "[[Billie Jean]]" video a number of freeze frames are shown in split screen.  Video and film director [[Michel Gondry]] has made extensive use of split screen techniques in his videos. One notable example is "Sugar Water" - [[Cibo Matto]] (1996), where one side of the screen shows the video played normally, and the other side shows the same video played backwards. Through careful and creative staging the two sides appear to interact directly - passing objects from side to side and visually referencing each other. The music video for "[[Doo Wop (That Thing)]]" by [[Lauryn Hill]] was filmed using a split screen technique, the video features Lauryn, performing the song at block parties in two different eras: the mid-1960s (The year 1967 is shown on the left of the video) and the late-1990s (The year 1998 is shown on the right).\n\n The split screen has also been used extensively in television programs. Newscasts often show two reporters in a split screen frame. The sitcom ''[[That '70s Show]]'', [[Nickelodeon]] teen sitcom ''[[Drake & Josh]]'', [[Disney Channel]] teen sitcom ''[[Lizzie McGuire]]'', [[USA Network]]'s ''[[Burn Notice]]'' and Fox's ''[[24 (TV series)|24]]'' made extensive use of split screens. It is sometimes used in [[game show]]s to show two contestants simultaneously, and on cable news shows, when participants in a discussion are in different locations.\n\nSplit screens are frequently used in motor racing, especially during [[safety car]] [[pit stop]]s in the [[IndyCar Series]] and [[NASCAR]], where four way splits are used, most often with three leading cars or trucks' pit stops shown on the left and a shot of the pit exit (where restart order is determined after pit stops) on the right, with some featuring just four different cars or trucks making pit stops. Often these pit stops can change the entire outcome of a race. In sports, an instant replay, highlights package, or featurette on a specific subject relating to the play may be shown in a corner while the main play is happening.\n\nIn 2019, Snapchat's original content arm, Snap Originals, released a series called 'Two Sides', which followed a young couple as they navigated a breakup, told from both perspectives at the same time.<ref>https://snaporiginals.snapchat.com/two-sides</ref> Season Two and Season Three will be released in 2021. \n\nSplit screens are sometimes used during commercial breaks, as in ESPN's "[[Side-By-Side (graphic)|Side-By-Side]]" coverage of racing, where one side of the screen shows race footage and the other shows advertising. This allows commercial to be shown while not interrupting coverage of race action.\n\nSplit screens are also common in [[advertising]], often to show [[comparative advertising|comparison]].", "Split screen (video production) --- Introduction ---|Notable uses of split screen": "<!-- Please limit this to examples with visible division of images, not "invisible" split screens for special effects purposes (i.e., ''The Parent Trap'', ''Back to the Future Part II'') -->\n\n{| class="wikitable"\n|-\n! Title\n! Year\n! Director\n! Notes\n|-\n| style=white-space:nowrap | ''[[Santa Claus (1898 film)|Santa Claus]]''\n| 1898\n| [[George Albert Smith (film pioneer)|George Albert Smith]]\n|\n|-\n| ''[[Life of an American Fireman]]''\n| 1903\n|[[Edwin S. Porter]]\n|\n|-\n| ''[[Suspense (1913 film)|Suspense]]''\n| 1913\n| [[Lois Weber]]\n|\n|-\n| ''[[The Queen of Spades (1916 film)|The Queen of Spades]]''\n| 1916\n| [[Yakov Protazanov]]\n|\n|-\n| ''[[Napol\u00e9on (movie)|Napol\u00e9on]]''\n| 1927\n| [[Abel Gance]]\n| Presented with three projectors in [[Polyvision]]\n|-\n| ''[[Pillow Talk (film)|Pillow Talk]]''\n| 1959\n| [[Michael Gordon (film director)|Michael Gordon]]\n|\n|-\n| ''[[The Patty Duke Show]]''\n| 1963\u20131966\n| Various\n| Television series in which the actress, [[Patty Duke]], played twin characters \u2014 identical cousins, Patty and Cathy \u2014 throughout the 105-episode run of the programme.\n|-\n| ''[[To Be Alive!]]''\n| 1964\n| {{plainlist|\n* [[Alexandr Hackenschmied|Alexander Hammid]]\n* Francis Thompson}}\n| Short film produced for the [[1964 New York World's Fair]], presented on multiple screens\n|-\n| ''[[Chelsea Girls]]''\n| 1966\n| {{plainlist|\n* [[Paul Morrissey]]\n* [[Andy Warhol]]\n}}\n| Presented side by side with two projectors for film's entirety\n|-\n| ''[[Grand Prix (1966 film)|Grand Prix]]''\n| 1966\n| [[John Frankenheimer]]\n|\n|-\n| ''[[A Place to Stand (film)|A Place to Stand]]''\n| 1967\n| [[Christopher Chapman]]\n| Originally presented at [[Expo 67]]\n|-\n| ''[[In the Labyrinth (film)|In the Labyrinth]]''\n| 1967\n| {{plainlist|\n* [[Roman Kroitor]]\n* [[Colin Low (filmmaker)|Colin Low]]\n* [[Hugh O'Connor (filmmaker)|Hugh O'Connor]]}}\n| Originally presented on multiple screens at [[Expo 67]]; later reissued in a single-screen format\n|-\n| ''[[Col cuore in gola]]''\n| 1967\n| [[Tinto Brass]]\n| \n|-\n| ''[[Charly]]''\n| 1968\n| [[Ralph Nelson]]\n| \n|-\n| ''[[The Thomas Crown Affair (1968 film)|The Thomas Crown Affair]]''\n| 1968\n| [[Norman Jewison]]\n|\n|-\n| ''[[The Boston Strangler (film)|The Boston Strangler]]''\n| 1968\n| [[Richard Fleischer]]\n|\n|-\n| ''[[Eagles Over London]]''\n| 1969\n| [[Enzo G. Castellari]]\n|\n|-\n| ''[[Airport (1970 film)|Airport]]''\n| 1970\n| [[George Seaton]]\n|\n|-\n| ''[[Dionysus in '69]]''\n| 1970\n| [[Brian De Palma]]\n| Presented side by side through optical printing for film's entirety\n|-\n| ''[[Multiple Sidosis]]''\n| 1970\n| Sid Lavarents\n| Short film\n|-\n| ''[[Woodstock (film)|Woodstock]]''\n| 1970\n| [[Michael Wadleigh]]\n| Documentary of the [[Woodstock]] Festival\n|-\n| ''[[The Andromeda Strain (film)|The Andromeda Strain]]''\n| 1971\n| [[Robert Wise]]\n| \n|-\n| ''[[Sisters (1973 film)|Sisters]]''\n| 1973\n| [[Brian De Palma]]\n|\n|-\n| ''[[Wicked, Wicked]]''\n| 1973\n| [[Richard L. Bare]]\n| Presented side by side through optical printing for film's entirety\n|-\n| ''[[Phantom of the Paradise]]''\n| 1974\n| [[Brian De Palma]]\n| \n|-\n| ''[[Carrie (1976 film)|Carrie]]''\n| 1976\n| [[Brian De Palma]]\n| \n|-\n| ''[[Twilight's Last Gleaming]]''\n| 1977\n| [[Robert Aldrich]]\n| \n|-\n| ''[[Dressed to Kill (1980 film)|Dressed to Kill]]''\n| 1980\n| [[Brian De Palma]]\n|\n|-\n| ''[[Blow Out]]''\n| 1981\n| [[Brian De Palma]]\n|\n|-\n| ''[[Sammy and Rosie Get Laid]]''\n| 1987\n| Stephen Frears\n|\n|-\n| ''[[Wall Street (1987 film)|Wall Street]]''\n| 1987\n| [[Oliver Stone]]\n| \n|-\n| ''[[The Bonfire of the Vanities (film)|The Bonfire of the Vanities]]''\n| 1990\n| [[Brian De Palma]]\n|\n|-\n|''[[Repossessed (film)|Repossessed]]''\n|1992\n|[[Bob Logan (film director)|Bob Logan]]\n|Used for comedic effect in a telephone conversation scene where one character crosses the "split" after the other person leave their phone off the hook.\n|-\n| ''[[Boogie Nights]]''\n| 1997\n| style=white-space:nowrap| [[Paul Thomas Anderson]]\n|\n|-\n| ''[[Jackie Brown (film)|Jackie Brown]]''\n| 1997\n| [[Quentin Tarantino]]\n|\n|-\n| "[[Closing Time (Semisonic song)#Music video|Closing Time]]"\n| 1998\n| Chris Applebaum\n| Music video for the Semisonic song\n|-\n| ''[[Snake Eyes (1998 film)|Snake Eyes]]''\n| 1998\n| [[Brian De Palma]]\n|\n|-\n| ''[[Run Lola Run]]''\n| 1998\n| [[Tom Tykwer]]\n|\n|-\n| ''[[The X-Files]]''\n| 1998\n| Chris Carter\n| Episode "[[Triangle (The X-Files)|Triangle]]"\n|-\n| ''[[The Virgin Suicides (film)|The Virgin Suicides]]''\n| 1999\n| [[Sofia Coppola]]\n|-\n| ''[[SpongeBob SquarePants]]''\n| 1999\n| [[Stephen Hillenburg]]\n| Used on '''Missing Identity''' episode.\n|-\n| ''[[The Boy Who Saw the Iceberg]]''\n| 2000\n| [[Paul Driessen (animator)|Paul Driessen]]\n| Animated short\n|-\n| ''[[Requiem for a Dream]]''\n| 2000\n| [[Darren Aronofsky]]\n|\n|-\n| ''[[Snatch (film)|Snatch]]''\n| 2000\n| [[Guy Ritchie]]\n|\n|-\n| ''[[Timecode (film)|Timecode]]''\n| 2000\n| [[Mike Figgis]]\n| Screen is split into quadrants, each showing a different sequence\n|-\n| ''[[24 (TV series)|24]]''\n| 2001\u201310, 2014\n| [[Stephen Hopkins (director)|Stephen Hopkins]], Various\n| Television series\n|-\n| ''[[Femme Fatale (2002 film)|Femme Fatale]]''\n| 2002\n| [[Brian De Palma]]\n|\n|-\n| ''[[Adaptation (film)|Adaptation]]''\n| 2002\n| [[Spike Jonze]]\n|\n|-\n| ''[[The Rules of Attraction (film)|The Rules of Attraction]]''\n| 2002\n| [[Roger Avary]]\n|\n|-\n| ''[[Spooks (TV series)|Spooks]]''\n| 2002\n| Various\n| Television series<ref>{{cite web|url=http://film.thedigitalfix.com/content/id/5519/spooks-season-one.html|title=Film @ The Digital Fix - Spooks: Season One|work=Film @ The Digital Fix|access-date=1 February 2016}}</ref>\n|-\n| ''[[Down with Love]]''\n| 2003\n| [[Peyton Reed]]\n|\n|-\n| ''[[Kill Bill]]''\n| 2003\n| [[Quentin Tarantino]]\n|\n|-\n| ''Pretend''\n| 2003\n| [[Julie Talen]]\n|\n|-\n| ''[[Hulk (film)|Hulk]]''\n| 2003\n| [[Ang Lee]]\n|\n|-\n| ''[[Sexual Dependency (film)|Sexual Dependency]]''\n| 2003\n| Rodrigo Bellott\n|\n|-\n| ''[[Sideways]]''\n| 2004\n| [[Alexander Payne]]\n|\n|-\n| ''[[Conversations with Other Women]]''\n| 2005\n| [[Hans Canosa]]\n|\n|-\n| ''[[The Tracey Fragments (film)|The Tracey Fragments]]''\n| 2007\n| [[Bruce McDonald (director)|Bruce McDonald]]\n|\n|-\n| ''[[A Wednesday!]]''\n| 2008\n| [[Neeraj Pandey]]\n| Hindi film\n|\n|-\n|''[[OSS 117: Lost in Rio]]\n|2009\n|[[Michel Hazanavicius]]\n|\n|-\n| ''[[500 Days of Summer]]''\n| 2009\n| [[Marc Webb]]\n|\n|-\n| ''[[127 Hours]]''\n| 2010\n| [[Danny Boyle]]\n| \n|-\n| ''[[Scott Pilgrim vs. the World]]''\n| 2010\n| [[Edgar Wright]]\n| \n|-\n| ''[[The Social Network]]''\n| 2010\n| [[David Fincher]]\n|\n|-\n| ''[[Love, Chunibyo & Other Delusions]]''\n| 2012\n| [[Tatsuya Ishihara]]\n| [[Anime]] series<ref>{{cite web|url=http://www.fandompost.com/2014/01/09/love-chunibyo-other-delusions-ren-episode-01-anime-review/|title=Love, Chunibyo & Other Delusions! REN Episode #01 Anime Review|author=Kestrel Swift|date=9 January 2014|work=The Fandom Post|access-date=1 February 2016}}</ref>\n|-\n| [[Dhoom 3]]\n| 2013\n| [[Vijay Krishna Acharya]]\n| [[Bollywood|Hindi Film]]\n|-\n| ''[[R... Rajkumar]]''\n| 2013\n| [[Prabhu Deva]]\n| One Scene / [[Bollywood|Hindi Film]]\n|-\n| ''[[Kalyeserye]]''\n| 2015–2016\n| Bert de Leon, Poochie Rivera, Rich Ilustre\n| A soap opera parody aired live during the "Juan for All, All for Juan" segment of Philippine noontime variety show ''[[Eat Bulaga!]]'' on [[GMA Network]] in the Philippines.<ref>{{cite web|url=http://entertainment.inquirer.net/176591/split-screen-tv-fairy-tale-aldub-hit-in-old-new-media|title=Split-screen TV fairy tale 'AlDub' hit in old, new media|author=Bayani San Diego Jr.|work=inquirer.net|access-date=1 February 2016}}</ref>\n|-\n| ''[[The Man from U.N.C.L.E. (film)|The Man from U.N.C.L.E.]]''\n| 2015\n| [[Guy Ritchie]]\n| \n|-\n| ''[[Fargo (TV series)|Fargo]]''\n| 2015\n| [[Randall Einhorn]]\n| Season 2\n|-\n| ''[[The Mindy Project]]''\n| 2017\n| Various\n| Final Season\n|-\n| ''[[The Indian Detective]]''\n| 2017\n| Various\n| Mini-series\n|}"}},
{"article_title": "Superfluid helium-4", "pageid": "27573", "revid": "1036631436", "timestamp": "2021-08-01T19:31:26Z", "history_paths": [["Superfluid helium-4 --- Introduction ---", "History"]], "categories": ["liquid helium", "bose\u2013einstein condensates", "fluid dynamics", "emerging technologies", "superfluidity"], "heading_tree": {"Superfluid helium-4 --- Introduction ---": {"History": {}, "Applications": {}, "Properties": {"Film flow": {}, "Rotation": {}, "Comparison with helium-3": {}}, "Macroscopic theory": {"Thermodynamics": {}, "Superfluid hydrodynamics": {}, "Fountain pressure": {}, "Heat transport": {}}, "Microscropic theory": {"Landau two-fluid approach": {}, "Vortex ring model": {}, "Hard-sphere models": {}, "Gaussian cluster approach": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Superfluid helium-4 --- Introduction ---|History": "Known as a major facet in the study of [[quantum hydrodynamics]] and [[macroscopic quantum phenomena]], the [[superfluidity]] effect was discovered by [[Pyotr Kapitsa]]<ref>{{cite journal|last1=Kapitza|first1=P.|date=1938|title=Viscosity of Liquid Helium Below the \u03bb-Point|journal=Nature|volume=141|issue=3558|page=74|bibcode=1938Natur.141...74K|doi=10.1038/141074a0|s2cid=3997900|doi-access=free}}</ref> and [[John F. Allen]], and [[Don Misener]]<ref>{{cite journal|last1=Allen|first1=J. F.|last2=Misener|first2=A. D.|date=1938|title=Flow of Liquid Helium II|journal=Nature|volume=142|issue=3597|page=643|bibcode=1938Natur.142..643A|doi=10.1038/142643a0|s2cid=4135906}}</ref> in 1937. It has since been described through [[Phenomenology (particle physics)|phenomenological]] and microscopic theories. \n\nIn the 1950s, Hall and Vinen performed experiments establishing the existence of [[quantized vortex]] lines in superfluid helium.<ref>{{cite journal|last1=Hall|first1=H. E.|last2=Vinen|first2=W. F.|date=1956|title=The Rotation of Liquid Helium II. II. The Theory of Mutual Friction in Uniformly Rotating Helium II|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=238|issue=1213|page=215|bibcode=1956RSPSA.238..215H|doi=10.1098/rspa.1956.0215|s2cid=120738827}}</ref> In the 1960s, Rayfield and Reif established the existence of quantized vortex rings.<ref>{{cite journal|last1=Rayfield|first1=G.|last2=Reif|first2=F.|date=1964|title=Quantized Vortex Rings in Superfluid Helium|journal=Physical Review|volume=136|issue=5A|pages=A1194|bibcode=1964PhRv..136.1194R|doi=10.1103/PhysRev.136.A1194}}</ref> Packard has observed the intersection of vortex lines with the free surface of the fluid,<ref>{{cite journal|last1=Packard|first1=Richard E.|date=1982|title=Vortex photography in liquid helium|url=http://physics.berkeley.edu/sites/default/files/_/vortexphotography1982_0.pdf|journal=Physica B|volume=109\u2013110|pages=1474\u20131484|bibcode=1982PhyBC.109.1474P|citeseerx=10.1.1.210.8701|doi=10.1016/0378-4363(82)90510-1}}</ref>\nand Avenel and Varoquaux have studied the [[Josephson effect]] in superfluid helium-4.<ref>{{cite journal|last1=Avenel|first1=O.|last2=Varoquaux|first2=E.|date=1985|title=Observation of Singly Quantized Dissipation Events Obeying the Josephson Frequency Relation in the Critical Flow of Superfluid ^{4}He through an Aperture|journal=Physical Review Letters|volume=55|issue=24|pages=2704\u20132707|bibcode=1985PhRvL..55.2704A|doi=10.1103/PhysRevLett.55.2704|pmid=10032216}}{{Dead link|date=June 2018|bot=InternetArchiveBot|fix-attempted=no}}</ref> In 2006, a group at the University of Maryland visualized quantized vortices by using small tracer particles of [[solid hydrogen]].<ref>{{cite journal|last1=Bewley|first1=Gregory P.|last2=Lathrop|first2=Daniel P.|last3=Sreenivasan|first3=Katepalli R.|date=2006|title=Superfluid helium: Visualization of quantized vortices|url=http://users.ictp.it/~krs/pdf/2006_001.pdf|journal=Nature|volume=441|issue=7093|page=588|bibcode=2006Natur.441..588B|doi=10.1038/441588a|pmid=16738652|s2cid=4429923|doi-access=free}}</ref>\n\nIn the early 2000s, physicists created a [[Fermionic condensate]] from pairs of ultra-cold fermionic atoms. Under certain conditions, fermion pairs form [[diatomic molecule]]s and undergo [[Bose\u2013Einstein condensation]]. At the other limit, the fermions (most notably superconducting electrons) form [[Cooper pairs]] which also exhibit superfluidity. This work with ultra-cold atomic gases has allowed scientists to study the region in between these two extremes, known as the [[BEC-BCS crossover]].\n\n[[Supersolid]]s may also have been discovered in 2004 by physicists at [[Penn State University]]. When helium-4 is cooled below about 200 mK under high pressures, a fraction (\u22481%) of the solid appears to become superfluid.<ref>{{Cite journal|author=[[Kim Eunseong|E. Kim]] and [[Moses H. W. Chan|M. H. W. Chan]]|date=2004|title=Probable Observation of a Supersolid Helium Phase|journal=Nature|volume=427|issue=6971|pages=225\u2013227|bibcode=2004Natur.427..225K|doi=10.1038/nature02220|pmid=14724632|s2cid=3112651}}</ref><ref>Moses Chan's Research Group. "[http://www.phys.psu.edu/~chan/index_files/Page526.htm Supersolid] {{webarchive|url=https://web.archive.org/web/20130408065008/http://www.phys.psu.edu/~chan/index_files/Page526.htm|date=2013-04-08}}." ''Penn State University,'' 2004.</ref> By quench cooling or lengthening the [[annealing (metallurgy)|annealing]] time, thus increasing or decreasing the defect density respectively, it was shown, via torsional oscillator experiment, that the supersolid fraction could be made to range from 20% to completely non-existent. This suggested that the supersolid nature of helium-4 is not intrinsic to helium-4 but a property of helium-4 and disorder.<ref>{{Cite journal|last=Sophie|first=A|author2=Rittner C|date=2006|title=Observation of Classical Rotational Inertia and Nonclassical Supersolid Signals in Solid 4 He below 250 mK|journal=Phys. Rev. Lett.|volume=97|issue=16|page=165301|arxiv=cond-mat/0604528|bibcode=2006PhRvL..97p5301R|doi=10.1103/PhysRevLett.97.165301|pmid=17155406|s2cid=45453420}}</ref><ref>{{Cite journal|last=Sophie|first=A|author2=Rittner C|date=2007|title=Disorder and the Supersolid State of Solid 4 He|journal=Phys. Rev. Lett.|volume=98|issue=17|page=175302|arxiv=cond-mat/0702665|bibcode=2007PhRvL..98q5302R|doi=10.1103/PhysRevLett.98.175302|s2cid=119469548}}</ref> Some emerging theories posit that the supersolid signal observed in helium-4 was actually an observation of either a [[superglass]] state<ref>{{Cite journal|last=Boninsegni|first=M|author2=Prokofev|date=2006|title=Superglass Phase of 4 He|journal=Phys. Rev. Lett.|volume=96|issue=13|page=135301|arxiv=cond-mat/0603003|bibcode=2006PhRvL..96m5301W|doi=10.1103/PhysRevLett.96.135301|pmid=16711998|s2cid=41657202}}</ref> or intrinsically superfluid grain boundaries in the helium-4 crystal.<ref>{{Cite journal|last=Pollet|first=L|author2=Boninsegni M|date=2007|title=Superfuididty of Grain Boundaries in Solid 4 He|journal=Phys. Rev. Lett.|volume=98|issue=13|page=135301|arxiv=cond-mat/0702159|bibcode=2007PhRvL..98m5301P|doi=10.1103/PhysRevLett.98.135301|pmid=17501209|s2cid=20038102}}</ref>"}},
{"article_title": "Steam engine", "pageid": "27692", "revid": "1062910019", "timestamp": "2021-12-31T03:42:31Z", "history_paths": [["Steam engine --- Introduction ---", "History"]], "categories": ["steam engines", "steam power", "18th-century inventions", "energy conversion", "english inventions", "gas technologies", "piston engines"], "heading_tree": {"Steam engine --- Introduction ---": {"History": {"Early experiments": {}, "Pumping engines": {}, "Piston steam engines": {}, "High-pressure engines": {}, "Horizontal stationary engine": {}, "Road vehicles": {}, "Marine engines": {}, "Steam locomotives": {}, "Steam turbines": {}, "Present development": {}}, "Components and accessories of steam engines": {"Heat source": {}, "Boilers": {}, "Motor units": {}, "Cold sink": {}, "Water pump": {}, "Monitoring and control": {}, "Governor": {}}, "Engine configuration": {"Simple engine": {}, "Compound engines": {}, "Multiple-expansion engines": {}}, "Types of motor units": {"Reciprocating piston": {"Compression": {}, "Lead": {}}, "Uniflow (or unaflow) engine": {}, "Turbine engines": {}, "Oscillating cylinder steam engines": {}, "Rotary steam engines": {}, "Rocket type": {}}, "Safety": {}, "Steam cycle": {}, "Efficiency": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Steam engine --- Introduction ---|History": "{{main|History of the steam engine}}\n\n The first recorded rudimentary steam-powered "engine" was the [[aeolipile]] described by [[Hero of Alexandria]], a Greek mathematician and engineer in [[Egypt (Roman province)|Roman Egypt]] in the first century AD.<ref>{{cite encyclopedia |url=http://www.britannica.com/eb/article-45691 |title=turbine |encyclopedia=Encyclop\u00e6dia Britannica Online |date=18 July 2007}}</ref> In the following centuries, the few steam-powered "engines" known were, like the aeolipile,<ref name="Vitruvius">''"De Architectura"'': Chapter VI (paragraph 2)<br />from "Ten Books on Architecture" by [[Vitruvius]] (1st century BC), published 17, June, 08 [https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Vitruvius/1*.html] accessed 2009-07-07</ref> essentially experimental devices used by inventors to demonstrate the properties of steam. A rudimentary [[steam turbine]] device was described by [[Taqi al-Din Muhammad ibn Ma'ruf|Taqi al-Din]]<ref name=Hassan>[[Ahmad Y Hassan]] (1976). ''Taqi al-Din and Arabic Mechanical Engineering'', pp. 34\u201335. Institute for the History of Arabic Science, [[University of Aleppo]].</ref> in [[Ottoman Egypt]] in 1551 and by [[Giovanni Branca]]<ref name= Giovanni>{{cite web\n  |url=http://himedo.net/TheHopkinThomasProject/TimeLine/Wales/Steam/URochesterCollection/Thurston/index.html<!-- http://www.history.rochester.edu/steam/thurston/1878/Chapter1.html -->\n  |title= University of Rochester, NY, ''The growth of the steam engine'' online history resource, chapter one\n  |publisher=History.rochester.edu |access-date=2010-02-03\n}}</ref> in Italy in 1629.{{sfn|Nag|2002|p=432\u2013}} The Spanish inventor [[Jer\u00f3nimo de Ayanz y Beaumont]] received patents in 1606  for 50 steam-powered inventions, including a water pump for draining inundated mines.<ref>{{cite book|last=Garcia|first=Nicholas|title=Mas alla de la Leyenda Negra|year=2007|publisher=Universidad de Valencia|location=Valencia|isbn=978-84-370-6791-9|pages=443\u201354}}</ref> [[Denis Papin]], a [[Huguenot]], did some useful work on the [[steam digester]] in 1679, and first used a piston to raise weights in 1690.{{sfn|Hills|1989|pp=15, 16, 33}}<!-- Ref back to Farey- Dates need checking-->\n\n The first commercial steam-powered device was a water pump, developed in 1698 by [[Thomas Savery]].<ref name=Lira>{{cite web|last=Lira|first=Carl T.|title=The Savery Pump |work=Introductory Chemical Engineering Thermodynamics |publisher=Michigan State University|url=http://www.egr.msu.edu/~lira/supp/steam/savery.htm |access-date=11 April 2014|date=21 May 2013}}</ref> It used condensing steam to create a vacuum which raised water from below and then used steam pressure to raise it higher. Small engines were effective though larger models were problematic. They had a very limited lift height and were prone to [[boiler explosion]]s. Savery's engine was used in mines, [[pumping station]]s and supplying water to [[water wheel]]s powering textile machinery.<ref name=Hills16-20>{{Harvnb|Hills|1989|pp=16\u201320}}</ref> Savery's engine was of low cost. [[Bento de Moura Portugal]] introduced an improvement of Savery's construction "to render it capable of working itself", as described by [[John Smeaton]] in the Philosophical Transactions published in 1751.<ref>{{cite journal|doi=10.1098/rstl.1751.0073|title=LXXII. An engine for raising water by fire; being on improvement of saver'y construction, to render it capable of working itself, invented by Mr. De Moura of Portugal, F. R. S. Described by Mr. J. Smeaton|journal=Philosophical Transactions of the Royal Society of London|volume=47|pages=436\u2013438|year=1752|s2cid=186208904}}</ref> It continued to be manufactured until the late 18th century.{{sfn|Landes|1969|p=}} At least one engine was still known to be operating in 1820.<ref>{{cite book\n|title=Links in the History of Engineering and Technology from Tudor Times\n|last=Jenkins\n|first= Ryhs\n|year=1971 |orig-year=First published 1936 |publisher =The Newcomen Society at the Cambridge University Press\n|location= Cambridge \n|isbn= 978-0-8369-2167-0\n}}. Collected Papers of Rhys Jenkins, Former Senior Examiner in the British Patent Office.</ref>\n\n \n[[File:Jacob Leupold Steam engine 1720.jpg|thumb|right|[[Jacob Leupold]]'s steam engine, 1720]]\n\nThe first commercially successful engine that could transmit continuous power to a machine was the [[atmospheric engine]], invented by [[Thomas Newcomen]] around 1712.{{efn|Landes{{sfn|Landes|1969|p=101}} refers to Thurston's definition of an engine and Thurston's calling Newcomen's the "first true engine."}}{{sfn|Brown|2002|pp=60-}} It improved on Savery's steam pump, using a piston as proposed by Papin. Newcomen's engine was relatively inefficient, and mostly used for pumping water. It worked by creating a partial vacuum by condensing steam under a piston within a cylinder. It was employed for draining mine workings at depths originally impractical using traditional means, and for providing reusable water for driving waterwheels at factories sited away from a suitable "head". Water that passed over the wheel was pumped up into a storage reservoir above the wheel.{{sfn|Hunter|1985|p=}}<ref>{{cite document\n  | last1=Nuvolari | first1=A\n  | last2=Verspagen | first2=Bart\n  | last3=Tunzelmann | first3=Nicholas\n  | date=2003\n  | title=The Diffusion of the Steam Engine in Eighteenth-Century Britain. Applied Evolutionary Economics and the Knowledge-based Economy\n  | publisher=Eindhoven Centre for Innovation Studies (ECIS)\n  | location=Eindhoven, The Netherlands\n  | page=3\n}}  (Paper to be presented at 50th Annual North American Meetings of the Regional Science Association International 20\u201322 November 2003)</ref>\nIn 1780 James Pickard patented the use of a flywheel and crankshaft to provide rotative motion from an improved Newcomen engine.{{sfn|Nuvolari|Verspagen|Tunzelmann|2003|p=4}}\n\nIn 1720, [[Jacob Leupold]] described a two-cylinder high-pressure steam engine.<ref>{{cite book\n  |last= Galloway |first= Elajah\n  |title= History of the Steam Engine\n  |publisher =B. Steill, Paternoster-Row |year=1828 |location=London\n  |pages=23\u201324\n}}</ref> The invention was published in his major work "Theatri Machinarum Hydraulicarum".<ref>{{cite book\n  |last= Leupold |first= Jacob\n  |title= Theatri Machinarum Hydraulicarum\n  |publisher= Christoph Zunkel |year=1725 |location=Leipzig\n}}</ref> The engine used two heavy pistons to provide motion to a water pump. Each piston was raised by the steam pressure and returned to its original position by gravity. The two pistons shared a common four-way [[rotary valve]] connected directly to a steam boiler.\n\n[[File:Watt steam pumping engine.JPG|thumb|Early [[Watt steam engine|Watt]] pumping engine]]\nThe next major step occurred when [[James Watt (inventor)|James Watt]] developed (1763\u20131775) [[Watt steam engine|an improved version]] of Newcomen's engine, with a [[History of the steam engine#Watt's separate condenser|separate condenser]]. [[Boulton and Watt]]'s early engines used half as much coal as [[John Smeaton]]'s improved version of Newcomen's.<ref name=HB>{{Harvnb|Hunter|Bryant|1991}} Duty comparison was based on a carefully conducted trial in 1778.</ref> Newcomen's and Watt's early engines were "atmospheric". They were powered by air pressure pushing a piston into the partial [[vacuum]] generated by [[condensation|condensing]] steam, instead of the [[pressure]] of expanding steam. The engine [[Cylinder (engine)|cylinders]] had to be large because the only usable force acting on them was [[atmospheric pressure]].{{sfn|Hunter|1985|p=}}<ref name="Rosen" />\n\nWatt developed his engine further, modifying it to provide a rotary motion suitable for driving machinery. This enabled factories to be sited away from rivers, and accelerated the pace of the Industrial Revolution.<ref name="Rosen">{{cite book\n|title=The Most Powerful Idea in the World: A Story of Steam, Industry and Invention\n|last1=Rosen\n|first1= William\n|year= 2012\n|publisher = University of Chicago Press\n|isbn= 978-0-226-72634-2 |page=185\n}}</ref>{{sfn|Hunter|1985|p=}}<ref name="Thomson 2009" />\n\n The meaning of high pressure, together with an actual value above ambient, depends on the era in which the term was used. For early use of the term Van Reimsdijk<ref>"The Pictorial History of Steam Power" J.T. Van Reimsdijk and Kenneth Brown, Octopus Books Limited 1989, {{ISBN|0-7064-0976-0}}, p. 30</ref> refers to steam being at a sufficiently high pressure that it could be exhausted to atmosphere without reliance on a vacuum to enable it to perform useful work. {{harvnb|Ewing|1894|p=22}} states that Watt's condensing engines were known, at the time, as low pressure compared to high pressure, non-condensing engines of the same period.\n\nWatt's patent prevented others from making high pressure and compound engines. Shortly after Watt's patent expired in 1800, [[Richard Trevithick]] and, separately, [[Oliver Evans]] in 1801<ref name="Thomson 2009">{{cite book |title     = Structures of Change in the Mechanical Age: Technological Invention in the United States 1790\u20131865\n |last      = Thomson\n |first     = Ross\n |year      = 2009\n |publisher = The Johns Hopkins University Press\n |location  = Baltimore, MD\n |isbn      = 978-0-8018-9141-0\n |page      = [https://archive.org/details/structuresofchan0000thom/page/34 34]\n |url       = https://archive.org/details/structuresofchan0000thom/page/34\n}}</ref><ref>{{Citation\n  |last=Cowan |first=Ruth Schwartz\n  |title=A Social History of American Technology\n  |publisher=Oxford University Press |place=New York\n  |year=1997\n  |page=74\n  |isbn=978-0-19-504606-9\n}}</ref> introduced engines using high-pressure steam; Trevithick obtained his high-pressure engine patent in 1802,<ref>{{cite book|last1=Dickinson|first1=Henry W|last2=Titley|first2=Arthur|title=Richard Trevithick, the engineer and the man|year=1934|publisher=Cambridge University Press|location=Cambridge, England|page=xvi|chapter=Chronology|oclc=637669420}}</ref> and Evans had made several working models before then.<ref>The American Car since 1775, Pub. L. Scott. Baily, 1971, p. 18</ref> These were much more powerful for a given cylinder size than previous engines and could be made small enough for transport applications. Thereafter, technological developments and improvements in manufacturing techniques (partly brought about by the adoption of the steam engine as a power source) resulted in the design of more efficient engines that could be smaller, faster, or more powerful, depending on the intended application.{{sfn|Hunter|1985|p=}}\n\nThe [[Cornish engine]] was developed by Trevithick and others in the 1810s.{{sfn|Hunter|1985|pp=601\u2013628}} It was a compound cycle engine that used high-pressure steam expansively, then condensed the low-pressure steam, making it relatively efficient. The Cornish engine had irregular motion and torque though the cycle, limiting it mainly to pumping. Cornish engines were used in mines and for water supply until the late 19th century.{{sfn|Hunter|1985|p=601}}\n\n {{Main|Stationary steam engine}}\n\nEarly builders of stationary steam engines considered that horizontal cylinders would be subject to excessive wear. Their engines were therefore arranged with the piston axis in vertical position. In time the horizontal arrangement became more popular, allowing compact, but powerful engines to be fitted in smaller spaces.\n\nThe acme of the horizontal engine was the [[Corliss steam engine]], patented in 1849, which was a four-valve counter flow engine with separate steam admission and exhaust valves and automatic variable steam cutoff. When Corliss was given the [[Rumford Medal]], the committee said that "no one invention since Watt's time has so enhanced the efficiency of the steam engine".<ref name="NE Manufacturers 1879">{{cite book\n  |title=New England Manufacturers and Manufactories\n  |author=Van Slyck, J.D.\n  |others=volume 1\n  |series=New England Manufacturers and Manufactories\n  |url=https://books.google.com/books?id=wAs4AQAAMAAJ\n  |year=1879\n  |publisher=Van Slyck\n  |page=198}}</ref> In addition to using 30% less steam, it provided more uniform speed due to variable steam cut off, making it well suited to manufacturing, especially cotton spinning.{{sfn|Hunter|1985|p=}}<ref name="Thomson 2009" />\n\n {{Main|History of steam road vehicles}}\n[[File:Steam powered road-locomotive from England.png|thumb|Steam powered road-locomotive from England]]\nThe first experimental road-going steam-powered vehicles were built in the late 18th century, but it was not until after [[Richard Trevithick]] had developed the use of high-pressure steam, around 1800, that mobile steam engines became a practical proposition. The first half of the 19th century saw great progress in steam vehicle design, and by the 1850s it was becoming viable to produce them on a commercial basis. This progress was dampened by legislation which limited or prohibited the use of steam-powered vehicles on roads. Improvements in vehicle technology continued from the 1860s to the 1920s. Steam road vehicles were used for many applications. In the 20th century, the rapid development of [[internal combustion engine]] technology led to the demise of the steam engine as a source of propulsion of vehicles on a commercial basis, with relatively few remaining in use beyond the [[Second World War]]. Many of these vehicles were acquired by enthusiasts for preservation, and numerous examples are still in existence. In the 1960s, the air pollution problems in California gave rise to a brief period of interest in developing and studying steam-powered vehicles as a possible means of reducing the pollution. Apart from interest by steam enthusiasts, the occasional replica vehicle, and experimental technology, no steam vehicles are in production at present.\n\n \n[[File:Triple expansion marine steam engine.jpg|thumb|right|A triple-expansion [[marine steam engine]] on the 1907 oceangoing tug [[Hercules (1907)|''Hercules'']]]]\n\n{{Main|Marine steam engine}}\n\nNear the end of the 19th century, compound engines came into widespread use. [[Compound steam engine|Compound engines]] exhausted steam into successively larger cylinders to accommodate the higher volumes at reduced pressures, giving improved efficiency. These stages were called expansions, with double- and triple-expansion engines being common, especially in shipping where efficiency was important to reduce the weight of coal carried.{{sfn|Hunter|1985|p=}} Steam engines remained the dominant source of power until the early 20th century, when advances in the design of the [[steam turbine]], [[electric motor]]s and [[internal combustion engine]]s gradually resulted in the replacement of reciprocating (piston) steam engines, with merchant shipping relying increasingly upon [[diesel engine]]s, and warships on the steam turbine.{{sfn|Hunter|1985|p=}}<ref Name="Wiser"/>\n\n {{Main|Steam locomotive|Traction engine|Steam tractor}}\n\nAs the development of steam engines progressed through the 18th century, various attempts were made to apply them to road and railway use.{{sfn|Payton|2004}}<!--Cugnot is probably ''not'' relevant here. However it is very likely that Murdoch influenced Trevithick.--> In 1784, [[William Murdoch]], a [[Scotland|Scottish]] inventor, built a model steam road locomotive.<ref>{{cite book\n  | last =Gordon\n  | first =W.J.\n  | title =Our Home Railways, volume one\n  | publisher =Frederick Warne and Co\n  | year =1910\n  | location =London\n  | pages =7\u20139\n  }}</ref> An early working model of a steam rail locomotive was designed and constructed by steamboat pioneer [[John Fitch (inventor)|John Fitch]] in the United States probably during the 1780s or 1790s.<ref>{{cite web|url=http://www.nps.gov/history/history/online_books/steamtown/shs2.htm |title=Nation Park Service Steam Locomotive article with photo of Fitch Steam model and dates of construction as 1780\u20131790 |publisher=Nps.gov |date=2002-02-14 |access-date=2009-11-03}}</ref>\nHis steam locomotive used interior bladed wheels {{clarify|date=August 2020}} guided by rails or tracks.\n[[File:Union Pacific 844, Painted Rocks, NV, 2009 (crop).jpg|thumb|[[Union Pacific 844]] a "FEF-3" 4-8-4 "Northern" type steam locomotive]]\nThe first full-scale working railway steam locomotive was built by [[Richard Trevithick]] in the [[United Kingdom of Great Britain and Ireland|United Kingdom]] and, on 21 February 1804, the world's first railway journey took place as Trevithick's unnamed steam locomotive hauled a train along the [[Rail transport|tramway]] from the [[Penydarren|Pen-y-darren]] ironworks, near [[Merthyr Tydfil]] to [[Abercynon]] in south [[Wales]].{{sfn|Payton|2004}}<ref>{{cite web |url=http://www.museumwales.ac.uk/en/rhagor/article/trevithic_loco/ |title=Richard Trevithick's steam locomotive | Rhagor |publisher=Museumwales.ac.uk |access-date=2009-11-03 |url-status=dead |archive-url=https://web.archive.org/web/20110415125004/http://www.museumwales.ac.uk/en/rhagor/article/trevithic_loco |archive-date=15 April 2011}}</ref><ref>{{cite news\n| title       = Steam train anniversary begins\n| url         = http://news.bbc.co.uk/1/hi/wales/3509961.stm\n| publisher   = [[BBC]]\n| access-date  = 2009-06-13\n| quote       = A south Wales town has begun months of celebrations to mark the 200th anniversary of the invention of the steam locomotive. Merthyr Tydfil was the location where, on 21 February 1804, Richard Trevithick took the world into the railway age when he set one of his high-pressure steam engines on a local iron master's tram rails\n| date=2004-02-21}}</ref> The design incorporated a number of important innovations that included using high-pressure steam which reduced the weight of the engine and increased its efficiency. Trevithick visited the Newcastle area later in 1804 and the [[Industrial railway|colliery railways]] in north-east England became the leading centre for experimentation and development of steam locomotives.<ref name="Garnett,2005">{{cite book |last=Garnett |first=A.F. |title=Steel Wheels |publisher=Cannwood Press |year=2005| pages=18\u201319}}</ref>\n\nTrevithick continued his own experiments using a trio of locomotives, concluding with the [[Catch Me Who Can]] in 1808. Only four years later, the successful twin-cylinder locomotive ''[[The Salamanca|Salamanca]]'' by [[Matthew Murray]] was used by the [[Wagonway#Edgeway, edge rails|edge railed]] [[rack and pinion]] [[Middleton Railway]].<ref name="Young,1923">{{cite book\n  |last=Young |first=Robert\n  |title=Timothy Hackworth and the Locomotive \n  |publisher=the Book Guild Ltd\n  |location=Lewes, UK\n  |year=2000\n  |edition=reprint of 1923\n}}</ref> In 1825 [[George Stephenson]] built the ''[[Locomotion No 1|Locomotion]]'' for the [[Stockton and Darlington Railway]]. This was the first public steam railway in the world and then in 1829, he built ''[[Stephenson's Rocket|The Rocket]]'' which was entered in and won the [[Rainhill Trials]].<ref name="Ellis,1968">{{cite book |title=The Pictorial Encyclopedia of Railways |author=Hamilton Ellis |publisher=The Hamlyn Publishing Group |year=1968 |pages=24\u201330}}</ref> The [[Liverpool and Manchester Railway]] opened in 1830 making exclusive use of steam power for both passenger and freight trains.\n\nSteam locomotives continued to be manufactured until the late twentieth century in places such as [[List of locomotives in China|China]] and the former [[East Germany]] (where the [[DR Class 52.80]] was produced).<ref>Michael Reimer, Dirk Endisch: ''Baureihe 52.80 \u2013 Die rekonstruierte Kriegslokomotive'', GeraMond, {{ISBN|3-7654-7101-1}}</ref>\n\n {{Main|Steam turbine}}\n\nThe final major evolution of the steam engine design was the use of steam [[turbine]]s starting in the late part of the 19th century. Steam turbines are generally more efficient than reciprocating piston type steam engines (for outputs above several hundred horsepower), have fewer moving parts, and provide rotary power directly instead of through a [[connecting rod]] system or similar means.<ref name=smil>{{Citation|page= 62| title=Creating the Twentieth Century: Technical Innovations of 1867\u20131914 and Their Lasting Impact|author= Vaclav Smil|isbn= 978-0-19-516874-7 |url=https://books.google.com/books?id=w3Mh7qQRM-IC&q=Transformer+coltman+1988&pg=PA71|access-date=2009-01-03|year=2005|publisher=Oxford University Press}}</ref> Steam turbines virtually replaced reciprocating engines in electricity generating stations early in the 20th century, where their efficiency, higher speed appropriate to generator service, and smooth rotation were advantages. Today most [[electric power]] is provided by steam turbines. In the United States, 90% of the electric power is produced in this way using a variety of heat sources.<ref name="Wiser">{{cite book|title=Energy resources: occurrence, production, conversion, use|last= Wiser |first= Wendell H.|year= 2000|publisher= Birkh\u00e4user|isbn= 978-0-387-98744-6|page= 190|url= https://books.google.com/books?d=UmMx9ixu90kC&pg=PA190&dq=electrical+power+generators+steam+percent&hl=en&ei=JppoTpVexNmBB4C72MkM&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDgQ6AEwATgK#v=onepage&q=steam&f=false}}</ref> Steam turbines were extensively applied for propulsion of large ships throughout most of the 20th century.\n\n {{Main|Advanced steam technology}}\n\nAlthough the reciprocating steam engine is no longer in widespread commercial use, various companies are exploring or exploiting the potential of the engine as an alternative to internal combustion engines. The company Energiprojekt AB in [[Sweden]] has made progress in using modern materials for harnessing the power of steam. The efficiency of Energiprojekt's steam engine reaches some 27\u201330% on high-pressure engines. It is a single-step, 5-cylinder engine (no compound) with superheated steam and consumes approx. {{convert|4|kg|lb|abbr=on}} of steam per kWh.<ref>{{cite web|url= http://www.energiprojekt.com/|title= Energiprojekt LTD \u2013 Biomass power plant, Steam pow|publisher= Energiprojekt.com|access-date= 2010-02-03|archive-url= https://web.archive.org/web/20080820071822/http://www.energiprojekt.com/|archive-date= 20 August 2008|url-status=dead}}</ref>{{Failed verification|date=January 2015}}"}},
{"article_title": "Semiconductor device fabrication", "pageid": "27696", "revid": "1062330039", "timestamp": "2021-12-27T20:29:57Z", "history_paths": [["Semiconductor device fabrication --- Introduction ---", "History"]], "categories": ["semiconductor device fabrication", "cleanroom technology", "mosfets"], "heading_tree": {"Semiconductor device fabrication --- Introduction ---": {"Size": {}, "History": {"20th century": {}, "21st century": {}}, "List of steps": {}, "Prevention of contamination and defects": {}, "Wafers": {}, "Processing": {"Front-end-of-line (FEOL) processing": {"Gate oxide and implants": {}}, "Back-end-of-line (BEOL) processing": {"Metal layers": {}, "Interconnect": {}}}, "Wafer test": {}, "Device test": {}, "Device yield": {}, "Die preparation": {}, "Packaging": {}, "Hazardous materials": {}, "Timeline of MOSFET demonstrations": {}, "Timeline of commercial MOSFET nodes": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Semiconductor device fabrication --- Introduction ---|History": "{{See also|List of semiconductor scale examples|Moore's law|MOS integrated circuit|Semiconductor industry|Transistor density}}\n\n The first [[MOSFET|metal\u2013oxide\u2013silicon field-effect transistors]] (MOSFETs) were fabricated by Egyptian engineer [[Mohamed M. Atalla]] and Korean engineer [[Dawon Kahng]] at [[Bell Labs]] between 1959 and 1960.<ref name="Lojek">{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |pages=321\u20133}}</ref> There were originally two types of MOSFET technology, [[PMOS logic|PMOS]] ([[p-type semiconductor|p-type]] MOS) and [[NMOS logic|NMOS]] ([[n-type semiconductor|n-type]] MOS).<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960: Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine: A Timeline of Semiconductors in Computers|publisher=[[Computer History Museum]] |access-date=August 31, 2019}}</ref> Both types were developed by Atalla and Kahng when they originally invented the MOSFET, fabricating both PMOS and NMOS devices at [[20 \u00b5m process|20{{nbsp}}\u00b5m]]<ref name="Lojek"/> and [[10 \u00b5m process|10{{nbsp}}\u00b5m]] scales.<ref>{{cite book |last1=Voinigescu |first1=Sorin |title=High-Frequency Integrated Circuits |date=2013 |publisher=[[Cambridge University Press]] |isbn=9780521873024 |page=164 |url=https://books.google.com/books?id=71dHe1yb9jgC&pg=PA164}}</ref>\n\nAn improved type of MOSFET technology, [[CMOS]], was developed by [[Chih-Tang Sah]] and [[Frank Wanlass]] at [[Fairchild Semiconductor]] in 1963.<ref name="computerhistory1963">{{cite web |title=1963: Complementary MOS Circuit Configuration is Invented |url=https://www.computerhistory.org/siliconengine/complementary-mos-circuit-configuration-is-invented/ |website=[[Computer History Museum]] |access-date=6 July 2019}}</ref><ref>{{cite journal |last1=Sah |first1=Chih-Tang |author1-link=Chih-Tang Sah |last2=Wanlass |first2=Frank |author2-link=Frank Wanlass |title=Nanowatt logic using field-effect metal-oxide semiconductor triodes |journal=1963 IEEE International Solid-State Circuits Conference. Digest of Technical Papers |date=February 1963 |volume=VI |pages=32\u201333 |doi=10.1109/ISSCC.1963.1157450}}</ref> CMOS was commercialised by [[RCA]] in the late 1960s.<ref name="computerhistory1963"/> RCA commercially used CMOS for its [[4000-series integrated circuits]] in 1968, starting with a 20{{nbsp}}\u00b5m process before gradually scaling to a [[10 \u00b5m process]] over the next several years.<ref name="Lojek330">{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |page=330 |url=https://books.google.com/books?id=2cu1Oh_COv8C&pg=PA330}}</ref>\n\nSemiconductor device manufacturing has since spread from [[Texas]] and [[California]] in the 1960s to the rest of the world, including [[Asia]], [[Europe]], and the [[Middle East]].\n\n The [[semiconductor industry]] is a global business today. The leading semiconductor manufacturers typically have facilities all over the world. [[Samsung Electronics]], the world's largest manufacturer of semiconductors, has facilities in South Korea and the US. [[Intel]], the second-largest manufacturer, has facilities in Europe and Asia as well as the US. [[TSMC]], the world's largest [[Foundry model|pure play foundry]], has facilities in Taiwan, China, Singapore, and the US. [[Qualcomm]] and [[Broadcom]] are among the biggest [[fabless]] semiconductor companies, outsourcing their production to companies like TSMC.<ref>{{Cite news|url=http://anysilicon.com/top-10-worldwide-semiconductor-sales-leaders-q1-2017/|title=Top 10 Worldwide Semiconductor Sales Leaders - Q1 2017 - AnySilicon|date=2017-05-09|work=AnySilicon|access-date=2017-11-19|language=en-US}}</ref> They also have facilities spread in different countries.\n\nSince 2009, "node" has become a commercial name for marketing purposes that indicates new generations of process technologies, without any relation to gate length, metal pitch or gate pitch.<ref>{{cite web|url=https://www.design-reuse.com/articles/43316/a-brief-history-of-process-node-evolution.html|title=A Brief History of Process Node Evolution|last=Shukla|first=Priyank|website=design-reuse.com|access-date=2019-07-09}}</ref><ref>{{cite web|url=https://www.extremetech.com/computing/184946-14nm-7nm-5nm-how-low-can-cmos-go-it-depends-if-you-ask-the-engineers-or-the-economists|title=14nm, 7nm, 5nm: How low can CMOS go? It depends if you ask the engineers or the economists\u2026|last=Hruska|first=Joel|website=[[ExtremeTech]]}}</ref><ref>{{cite web|url=https://wccftech.com/intel-losing-process-lead-analysis-7nm-2022/|title=Exclusive: Is Intel Really Starting To Lose Its Process Lead? 7nm Node Slated For Release in 2022|website=wccftech.com|date=2016-09-10}}</ref> For example, [[GlobalFoundries]]' [[7 nm]] process is similar to [[Intel]]'s [[10 nm]] process, thus the conventional notion of a process node has become blurred.<ref>{{cite web|url=https://www.eejournal.com/article/life-at-10nm-or-is-it-7nm-and-3nm/|title=Life at 10nm. (Or is it 7nm?) And 3nm - Views on Advanced Silicon Platforms|website=eejournal.com|date=2018-03-12}}</ref> Additionally, TSMC and [[Samsung]]'s 10 nm processes are only slightly denser than Intel's 14 nm in transistor density. They are actually much closer to Intel's 14 nm process than they are to Intel's 10 nm process (e.g. Samsung's 10 nm processes' fin pitch is the exact same as that of Intel's 14 nm process: 42 nm).<ref>{{Cite web|url=https://en.wikichip.org/wiki/10_nm_lithography_process#Industry|title=10 nm lithography process - WikiChip|website=en.wikichip.org}}</ref><ref>{{Cite web|url=https://en.wikichip.org/wiki/14_nm_lithography_process#Industry|title=14 nm lithography process - WikiChip|website=en.wikichip.org}}</ref>\n\nAs of 2019, [[14 nanometer]] and [[10 nanometer]] chips are in mass production by Intel, [[United Microelectronics Corporation|UMC]], TSMC, Samsung, [[Micron Technology|Micron]], [[SK Hynix]], [[Toshiba Memory]] and GlobalFoundries, with [[7 nanometer]] process chips in mass production by [[TSMC]] and [[Samsung]], although their 7{{nbsp}}nanometer node definition is similar to [[Intel]]'s 10 nanometer process. The [[5 nanometer]] process began being produced by Samsung in 2018.<ref>{{Cite web|url=https://www.anandtech.com/show/14231/samsung-completes-development-of-5-nm-euv-process-technology|title=Samsung Completes Development of 5nm EUV Process Technology|last=Shilov|first=Anton|website=[[AnandTech]]|access-date=2019-05-31}}</ref> As of 2019, the node with the highest [[transistor density]] is TSMC's 5{{nbsp}}nanometer N5 node,<ref>{{cite web |last1=Cheng |first1=Godfrey |title=Moore's Law is not Dead |url=https://www.tsmc.com/english/newsEvents/blog_article_20190814.htm |website=TSMC Blog |publisher=[[TSMC]] |date=14 August 2019 |access-date=18 August 2019}}</ref> with a density of 171.3{{nbsp}}million transistors per square millimeter.<ref>{{Cite web|url=https://fuse.wikichip.org/news/2207/tsmc-starts-5-nanometer-risk-production/|title=TSMC Starts 5-Nanometer Risk Production|last=Schor|first=David|date=2019-04-06|website=WikiChip Fuse|language=en-US|access-date=2019-04-07}}</ref> In 2019, Samsung and TSMC announced plans to produce [[3 nanometer]] nodes. GlobalFoundries has decided to stop the development of new nodes beyond 12 nanometers in order to save resources, as it has determined that setting up a new fab to handle sub-12 nm orders would be beyond the company's financial abilities.<ref>{{Cite web|url=https://www.anandtech.com/show/13277/globalfoundries-stops-all-7nm-development|title=GlobalFoundries Stops All 7nm Development: Opts To Focus on Specialized Processes|first=Anton Shilov, Ian|last=Cutress|website=www.anandtech.com}}</ref> {{As of|2019}}, Samsung is the industry leader in advanced semiconductor scaling, followed by TSMC and then Intel.<ref>{{cite news |title=Intel is "two to three years behind Samsung" in the race to 1nm silicon |url=https://www.pcgamesn.com/samsung/mbcfet-process-node-advantage-tsmc-intel |access-date=11 December 2019 |work=[[PCGamesN]] |date=20 May 2019}}</ref>"}},
{"article_title": "Stem cell", "pageid": "27783", "revid": "1058141981", "timestamp": "2021-12-01T18:45:45Z", "history_paths": [["Stem cell --- Introduction ---", "History"]], "categories": ["stem cells", "induced stem cells", "biotechnology", "cell biology", "cloning", "developmental biology"], "heading_tree": {"Stem cell --- Introduction ---": {"History": {}, "Properties": {"Self-renewal": {}, "Potency meaning": {}, "Identification": {}}, "Embryonic": {"Mesenchymal stem cells": {}, "Cell cycle control": {}}, "Fetal": {}, "Adult": {}, "Amniotic": {}, "Induced pluripotent": {"Cell cycle control": {}}, "Lineage": {}, "Therapies": {"Advantages": {}, "Disadvantages": {}, "Stem cell tourism": {}}, "Research": {"Investigations": {}}, "Notable studies": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Stem cell --- Introduction ---|History": "The term ''stem cell'' was coined by [[Theodor Boveri]] and [[Valentin Haecker]] in late 19th century.<ref name="origin">{{cite journal |last1=Ramalho-Santos |first1=Miguel |last2=Willenbring |first2=Holger |title=On the Origin of the Term 'Stem Cell' |journal=Cell Stem Cell |date=June 2007 |volume=1 |issue=1 |pages=35\u201338 |doi=10.1016/j.stem.2007.05.013 |pmid=18371332 }}</ref> Pioneering works in theory of blood stem cell were conducted in the beginning of 20th century by [[Artur Pappenheim]], [[Alexander Maximow]], [[Franz Ernst Christian Neumann]].<ref name="origin" />\n\nThe key properties of a stem cell were first defined by [[Ernest McCulloch]] and [[James Till]] at the University of Toronto and the Ontario Cancer Institute in the early 1960s. They discovered the blood-forming stem cell, the hematopoietic stem cell (HSC), through their pioneering work in mice. McCulloch and Till began a series of experiments in which bone marrow cells were injected into irradiated mice. They observed lumps in the spleens of the mice that were linearly proportional to the number of bone marrow cells injected. They hypothesized that each lump (colony) was a clone arising from a single marrow cell (stem cell). In subsequent work, McCulloch and Till, joined by graduate student [[Andrew John Becker]] and senior scientist [[Louis Siminovitch]], confirmed that each lump did in fact arise from a single cell. Their results were published in ''Nature'' in 1963. In that same year, Siminovitch was a lead investigator for studies that found colony-forming cells were capable of self-renewal, which is a key defining property of stem cells that Till and McCulloch had theorized.<ref>{{cite web|url=https://news.usask.ca/articles/research/2018/the-accidental-discovery-of-stem-cells.php|title =The Accidental Discovery of Stem Cells|last1=MacPherson|first1=Colleen|website=USask News|publisher=University of Saskatchewan|access-date=3 December 2019|ref=1|name-list-style=vanc}}</ref>\n\nThe first therapy using stem cells was a [[bone marrow transplant]] performed by French oncologist [[Georges Math\u00e9]] in 1958 on five workers at the [[Vin\u010da Nuclear Institute]] in [[Socialist Federal Republic of Yugoslavia|Yugoslavia]] who had been affected by a [[criticality accident]]. The workers all survived.<ref>[http://www.johnstonsarchive.net/nuclear/radevents/1958YUG1.html Vinca reactor accident, 1958] {{webarchive|url=https://web.archive.org/web/20110127110604/http://johnstonsarchive.net/nuclear/radevents/1958YUG1.html|date=27 January 2011}}, compiled by Wm. Robert Johnston</ref>\n\nIn 1981, embryonic stem (ES) cells were first isolated and successfully cultured using mouse blastocysts by British biologists [[Martin Evans]] and [[Matthew Kaufman]]. This allowed the formation of murine genetic models, a system in which the genes of mice are deleted or altered in order to study their function in pathology. By 1998, embryonic stem cells were first isolated by American biologist [[James Thomson (cell biologist)|James Thomson]], which made it possible to have new transplantation methods or various cell types for testing new treatments. In 2006, [[Shinya Yamanaka]]\u2019s team in Kyoto, Japan converted fibroblasts into pluripotent stem cells by modifying the expression of only four genes. The feat represents the origin of induced pluripotent stem cells, known as iPS cells.<ref name=":6">{{cite web|url=http://sitn.hms.harvard.edu/flash/2014/stem-cells-a-brief-history-and-outlook-2/|title=Stem Cells: A Brief History and Outlook|last1=Ferreira|first1=Leonardo|date=2014-01-03|website=Stem Cells: A Brief History and Outlook - Science in the News|publisher=WordPress|access-date=3 December 2019|ref=2|name-list-style=vanc}}</ref>\n\nIn 2011, a female [[maned wolf]], run over by a truck, underwent stem cell treatment at the [[Zoo Bras\u00edlia]], this being the first recorded case of the use of stem cells to heal injuries in a wild animal.<ref>Boyle, Rebecca. [https://www.popsci.com/science/article/2011-01/injured-brazilian-wolf-first-wild-animal-treated-stem-cells/ ''Injured Brazilian Wolf Is First Wild Animal Treated With Stem Cells'']. [[Popular Science]], January 15, 2011. Retrieved 2021-08-07.</ref><ref>[https://www.cfmv.gov.br/tratamento/comunicacao/noticias/2011/01/11/ ''Tratamento'']. Conselho Federal de Medicina Veterin\u00e1ria, 2011-11-01, (Portuguese). Retrieved 2021-08-07.</ref>"}},
{"article_title": "Streaming media", "pageid": "28682", "revid": "1062730768", "timestamp": "2021-12-30T05:16:03Z", "history_paths": [["Streaming media --- Introduction ---", "History"]], "categories": ["streaming media systems", "applications of distributed computing", "cloud storage", "file sharing networks", "film and video technology", "peer-to-peer computing", "peercasting", "television terminology", "promotion and marketing communications", "bundled products or services"], "heading_tree": {"Streaming media --- Introduction ---": {"Etymology": {}, "Precursors": {}, "History": {"Early development": {}, "Late 1990s to early 2000s": {}, "Business developments": {}, "Streaming wars": {}}, "Use by the general public": {"Transition from a DVD-based to streaming culture": {}, "The roots of music streaming: Napster": {"The fight for intellectual property rights: ''A&M Records, Inc. v. Napster, Inc.''": {}}, "Music streaming platforms": {}, "COVID-19 pandemic": {}}, "Technologies": {"Bandwidth": {}, "Protocols": {}, "Recording": {}}, "Applications and marketing": {}, "Challenges": {"Copyright issues": {}, "Greenhouse gas emissions": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Streaming media --- Introduction ---|History": "{{See also|Timeline of online video}}\nAttempts to display media on computers date back to the earliest days of computing in the mid-20th century. However, little progress was made for several decades, primarily due to the high cost and limited capabilities of computer hardware. From the late 1980s through the 1990s, consumer-grade personal computers became powerful enough to display various media. The primary technical issues related to streaming were having enough [[CPU]] and [[bus (computing)|bus]] [[Bandwidth (computing)|bandwidth]] to support the required data rates, achieving [[real-time computing]] performance required to prevent [[buffer underrun]] and enable smooth streaming of the content. However, computer networks were still limited in the mid-1990s, and audio and video media were usually delivered over non-streaming channels, such as playback from a local [[hard disk drive]] or [[CD-ROM]]s on the end user's computer.\n\nIn 1990 the first commercial [[Ethernet switch]] was introduced by [[Kalpana (company)|Kalpana]], which enabled the more powerful computer networks that led to the first streaming video solutions used by schools and corporations.\n\nPractical streaming media was only made possible with advances in [[data compression]], due to the impractically high bandwidth requirements of uncompressed media. Raw [[digital audio]] encoded with [[pulse-code modulation]] (PCM) requires a bandwidth of 1.4{{nbsp}}[[Mbit/s]] for uncompressed [[CD audio]], while raw [[digital video]] requires a bandwidth of 168{{nbsp}}Mbit/s for [[SD video]] and over 1000{{nbsp}}Mbit/s for [[FHD]] video.<ref>{{cite book |last1=Lee |first1=Jack |title=Scalable Continuous Media Streaming Systems: Architecture, Design, Analysis and Implementation |date=2005 |publisher=[[John Wiley & Sons]] |isbn=9780470857649 |page=25 |url=https://books.google.com/books?id=7fuvu52cyNEC&pg=PA25}}</ref>\n\n {{See also|Original net animation}}\n\nDuring the late 1990s and early 2000s, users had increased access to computer networks, especially the Internet. During the early 2000s, users had access to increased network [[Bandwidth (signal processing)|bandwidth]], especially in the [[Last mile (telecommunications)|last mile]]. These technological improvements facilitated the streaming of audio and video content to computer users in their homes and workplaces. There was also an increasing use of standard protocols and formats, such as [[TCP/IP]], [[HTTP]], [[HTML]] as the Internet became increasingly commercialized, which led to an infusion of investment into the sector.\n\nThe band [[Severe Tire Damage (band)|Severe Tire Damage]] was the first group to perform live on the Internet. On June 24, 1993, the band was playing a gig at [[PARC (company)|Xerox PARC]] while elsewhere in the building, scientists were discussing new technology (the [[Mbone]]) for broadcasting on the Internet using [[multicast]]ing. As proof of PARC's technology, the band's performance was broadcast and could be seen live in Australia and elsewhere. In a March 2017 interview, band member Russ Haines stated that the band had used approximately "half of the total bandwidth of the internet" to stream the performance, which was a {{resx|152|76}} pixel video, updated eight to twelve times per second, with audio quality that was, "at best, a bad telephone connection."<ref>[https://www.youtube.com/watch?v=HRa2pE5-Ny0 "History of the Internet Pt. 1 \u2013 The First Live Stream"]. ''From YouTube.com''. Internet Archive \u2013 Stream Division. 5 April 2017. Retrieved 13 January 2018.</ref>\n\n[[RealNetworks]] pioneered the broadcast of a [[baseball]] game between the [[New York Yankees]] and the [[Seattle Mariners]] over the Internet in 1995.<ref>{{cite web |url=http://www.fundinguniverse.com/company-histories/RealNetworks-Inc-Company-History.html |publisher=Funding Universe |title=RealNetworks Inc. |access-date=23 July 2011}}</ref> The first symphonic concert on the Internet\u2014a collaboration between the [[Seattle Symphony]] and guest musicians [[Slash (musician)|Slash]], [[Matt Cameron]], and [[Barrett Martin]]\u2014took place at the [[Paramount Theatre (Seattle, Washington)|Paramount Theater]] in [[Seattle]], Washington, on November 10, 1995.<ref>{{cite magazine |author=<!--Staff writer(s); no by-line.--> |title= Cyberian Rhapsody |magazine=Billboard |location= United States|publisher= Lynne Segall|date=17 February 1996}}</ref>\n\n The first commercial streaming product appeared in late 1992 and was named StarWorks.<ref name="StarWorks">{{Cite book |doi = 10.1109/CMPCON.1993.289623|chapter = Star ''Works''-a video applications server|title = Digest of Papers. Compcon Spring|year = 1993|last1 = Tobagi|first1 = F.A.|last2 = Pang|first2 = J.|pages = 4\u201311|isbn = 0-8186-3400-6|s2cid = 61039780}}</ref> StarWorks enabled on-demand MPEG-1 full-motion videos to be randomly accessed on corporate [[Ethernet]] networks. Starworks was from [[Starlight Networks]], who also pioneered live video streaming on Ethernet and via [[Internet Protocol]] over satellites with [[Hughes Network Systems]].<ref name="Starlight Networks and Hughes Network Systems">{{cite web |url=http://www.thefreelibrary.com/Starlight+Networks+and+Hughes+Network+Systems+Plan+Corporate...-a017588314 |title=Starlight Networks and Hughes Network Systems}}</ref> Other early companies that created streaming media technology include [[RealNetworks]] (originally known as Progressive Networks) and Protocomm both prior to widespread World Wide Web usage. Once the web became popular in the late 90s, streaming video on the internet blossomed from startups such as VDOnet (later acquired by RealNetworks) and Precept (later acquired by [[Cisco]]).\n\n[[Microsoft]] developed a media player known as [[ActiveMovie]] in 1995 that supported streaming media and included a proprietary streaming format, which was the precursor to the streaming feature later in [[Windows Media Player]] 6.4 in 1999. In June 1999 [[Apple Inc.|Apple]] also introduced a streaming media format in its [[QuickTime]] 4 application. It was later also widely adopted on websites along with RealPlayer and Windows Media streaming formats. The competing formats on websites required each user to download the respective applications for streaming and resulted in many users having to have all three applications on their computer for general compatibility.\n\nIn 2000 Industryview.com launched its "world's largest streaming video archive" website to help businesses promote themselves.<ref>{{cite magazine |last=Hebert |first=Steve |date=November 2000 |title=Streaming Video Opens New Doors |magazine=Videography|page=164}}</ref> Webcasting became an emerging tool for business marketing and advertising that combined the immersive nature of television with the interactivity of the Web. The ability to collect data and feedback from potential customers caused this technology to gain momentum quickly.<ref>{{cite magazine |last=Reinstein |first=Bill |date=25 June 2001 |title=Webcasts Mature as Marketing Tool |magazine=DM News|page=24}}</ref>\n\nAround 2002, the interest in a single, unified, streaming format and the widespread adoption of [[Adobe Flash]] prompted the development of a video streaming format through Flash, which was the format used in Flash-based players on [[video hosting]] sites. The first popular video streaming site, [[YouTube]], was founded by [[Steve Chen]], [[Chad Hurley]] and [[Jawed Karim]] in 2005. It initially used a Flash-based player, which played [[MPEG-4 AVC]] video and [[Advanced Audio Coding|AAC]] audio, but now defaults to [[HTML5 video]].<ref>{{Cite news|url=https://youtube-eng.googleblog.com/2015/01/youtube-now-defaults-to-html5_27.html|title=YouTube now defaults to HTML5 <nowiki><video></nowiki>|work=YouTube Engineering and Developers Blog|access-date=20 February 2018}}</ref> Increasing consumer demand for live streaming prompted YouTube to implement a new live streaming service to users.<ref>{{cite web |url=http://news.cnet.com/8301-17939_109-9883062-2.html |author=Josh Lowensohn |year=2008 |title=YouTube to Offer Live Streaming This Year |access-date=23 July 2011}}</ref> The company currently also offers a (secured) link returning the available connection speed of the user.<ref>{{cite web|url=https://www.youtube.com/my_speed# | title=YouTube Video Speed History | website=[[YouTube]] |access-date=30 April 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120426225550/http://www.youtube.com/my_speed |archive-date=26 April 2012 }}</ref>\n\nThe [[Recording Industry Association of America]] (RIAA) revealed through its 2015 earnings report that streaming services were responsible for 34.3 percent of the year's total [[music industry]]'s revenue, growing 29 percent from the previous year and becoming the largest source of income, pulling in around $2.4 billion.<ref>{{cite web|title=News and Notes on 2015 RIAA Shipment and Revenue Statistics|url=https://www.riaa.com/wp-content/uploads/2016/03/RIAA-2015-Year-End-shipments-memo.pdf|publisher=RIAA|access-date=5 January 2017}}</ref><ref>{{cite news|title=Streaming made more revenue for music industry in 2015 than digital downloads, physical sales|url=http://www.washingtontimes.com/news/2016/mar/23/streaming-made-more-revenue-for-music-industry-in-/|newspaper=The Washington Times|access-date=5 January 2017}}</ref> US streaming revenue grew 57 percent to $1.6 billion in the first half of 2016 and accounted for almost half of industry sales.<ref>{{cite news|last1=Shaw|first1=Lucas|title=The Music Industry Is Finally Making Money on Streaming|newspaper=Bloomberg.com|url=https://www.bloomberg.com/news/articles/2016-09-20/spotify-apple-drive-u-s-music-industry-s-8-first-half-growth|publisher=Bloomberg|access-date=5 January 2017|date=20 September 2016}}</ref><!--[[User:Kvng/RTH]]-->\n\n {{See also|List of streaming service providers}}\n\nThe term "streaming wars" was coined to discuss the new era of competition between video streaming services such as [[Netflix]], [[Amazon Prime Video]], [[Hulu]], [[HBO Max]], [[Disney+]], and [[Apple TV+]].<ref>{{Cite web|url=https://www.theverge.com/streaming-wars|title=Streaming Wars|website=The Verge|access-date=1 December 2019}}</ref>\n\nAs COVID lockdowns forced many to stay with streamed content, competition has become extremely fierce for online platforms, forcing them to find ways to differentiate themselves. One key way they have done this is by offering exclusive content, often self-produced and created specifically for a market. This approach to streaming competition, can have disadvantages for consumers and for the industry as a whole. One example of "streaming wars" in action was captured in the study \u201cStreaming wars - Exclusive content and platform competition in Brazil"<ref>{{Cite web|title=Streaming wars (Creative Economy Notes Series)|url=https://www.wipo.int/edocs/infogdocs/creative_industries/en/streaming-wars|access-date=2021-12-29|website=www.wipo.int|language=en}}</ref> prepared by the [[World Intellectual Property Organization|WIPO]] for its economic creative series. Their findings were that once content was made available online, the corresponding piracy searches decreased in Brazil by approximately 6% per year. In addition, the survey found that competition or legal availability across multiple platforms effectively deters online piracy and more exclusivity does not necessarily translate into higher average investment in content, as investment decisions are also dependent on the level and type of competition in online markets<ref>{{Cite web|title=Streaming wars (Creative Economy Notes Series)|url=https://www.wipo.int/edocs/infogdocs/creative_industries/en/streaming-wars|access-date=2021-12-29|website=www.wipo.int|language=en}}</ref>."}},
{"article_title": "SECAM", "pageid": "28706", "revid": "1062725805", "timestamp": "2021-12-30T04:24:09Z", "history_paths": [["SECAM --- Introduction ---", "History"]], "categories": ["film and video technology", "france\u2013soviet union relations", "television in the soviet union", "television technology", "television terminology", "television transmission standards", "video formats", "video signal", "standards of france"], "heading_tree": {"SECAM --- Introduction ---": {"History": {"Development": {}, "Geographic reach": {}}, "Technical details": {}, "SECAM varieties": {"L, B/G, D/K, H, K, M (broadcast)": {}, "MESECAM (home recording)": {"Technical details": {}}}, "Disadvantages": {}, "Countries and territories that use SECAM": {"Migration from SECAM to PAL": {"Europe": {}, "Africa": {}, "Asia": {}}, "Migration from SECAM to DVB-T": {}}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"SECAM --- Introduction ---|History": "Development of SECAM began in 1956 by a team led by [[Henri de France]] working at ''Compagnie Fran\u00e7aise de T\u00e9l\u00e9vision'' (later bought by Thomson, now [[Technicolor SA|Technicolor]]). The technology was ready by the end of the 1950s, but this was too soon for a wide introduction. A version of SECAM for the French [[Analog high-definition television systems|819-line television standard]] was devised and tested, but not introduced.<ref>{{Cite web|url=https://www.redsharknews.com/business/item/471-france-had-a-national-hd-tv-system-in-1949|title = France had a national HD TV system as far back as 1949}}</ref> Following a pan-European agreement to introduce color TV only in 625 lines, France had to start the conversion by switching over to a 625-line television standard, which happened at the beginning of the 1960s with the introduction of a second network.\n\nThe first proposed system was called '''SECAM I''' in 1961, followed by other studies to improve compatibility and image quality.\n\nThese improvements were called '''SECAM II''' and '''SECAM III''', with the latter being presented at the 1965 [[Comit\u00e9 consultatif international pour la radio|CCIR]] General Assembly in [[Vienna]].\n\nFurther improvements were '''SECAM III A''' followed by '''SECAM III B''', the adopted system for general use in 1967, and first SECAM broadcast was made in France that year. \n\n[[Soviet Union|Soviet]] technicians were involved in the development of the standard, and created their own incompatible variant called '''NIIR''' or '''SECAM IV''', which was not deployed. The team was working in [[Moscow]]'s [[Telecentrum]] under the direction of [[:ru:\u0428\u043c\u0430\u043a\u043e\u0432, \u041f\u0430\u0432\u0435\u043b \u0412\u0430\u0441\u0438\u043b\u044c\u0435\u0432\u0438\u0447|Professor Shmakov]].<!--Pavel Vasilyevich--> The '''NIIR''' designation comes from the name of the ''[[Nautchno-Issledovatelskiy Institut Radio]]'' (''NIIR'', ''rus.'' \u041d\u0430\u0443\u0447\u043d\u043e-\u0418\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u0441\u043a\u0438\u0439 \u0418\u043d\u0441\u0442\u0438\u0442\u0443\u0442 \u0420\u0430\u0434\u0438\u043e), a Soviet research institute involved in the studies. Two standards were developed: ''Non-linear NIIR'', in which a process analogous to [[gamma correction]] is used, and ''Linear NIIR'' or ''SECAM IV'' that omits this process.<ref>[http://www.pembers.freeserve.co.uk/World-TV-Standards/Colour-Standards.html#SECAM-IV SECAM-IV] {{webarchive|url=https://web.archive.org/web/20140221112432/http://www.pembers.freeserve.co.uk/World-TV-Standards/Colour-Standards.html |date=21 February 2014 }}</ref>\n\nSECAM was inaugurated in [[France]] on 1 October 1967, on ''la deuxi\u00e8me cha\u00eene'' (the second channel), now called [[France 2]]. A group of four suited men\u2014a presenter ([[Georges Gorse]], Minister of Information) and three contributors to the system's development\u2014were shown standing in a studio. Following a count from 10, at 2:15 pm the black-and-white image switched to color; the presenter then declared "''Et voici la couleur !''" ('''fr:''' And here is color!)<ref>{{cite web|title=INA: Pr\u00e9sentation officielle de la t\u00e9l\u00e9vision couleur|url=http://www.ina.fr/video/CPF86633716/presentation-officielle-de-la-television-couleur.fr.html|access-date=4 August 2014}}</ref> In 1967, CLT of [[Lebanon]] became the third television station in the world, after the Soviet Union and France, to broadcast in color utilizing the French SECAM technology.<ref>{{cite book|last1=Harb|first1=Zahera|title=Channels of resistance in Lebanon: liberation propaganda, Hezbollah and the media|date=2011|publisher=Tauris|page=95|location=London [etc.]|isbn=978-1-84885-120-7}}</ref>\n\nThe first color television sets cost 5000 Francs. Color TV was not very popular initially; only about 1500 people watched the inaugural program in color. A year later, only 200,000 sets had been sold of an expected million. This pattern was similar to the earlier slow build-up of color television popularity in the US.\n\nSECAM was later adopted by former French and [[Belgium|Belgian]] colonies, [[Greece]], [[Cyprus]], the [[Soviet Union]] and [[Eastern bloc]] countries (except for [[Romania]]), and some [[Middle East]]ern countries. However, with the [[Revolutions of 1989|fall of communism]], and following a period when multi-standard TV sets became a [[commodity]], many Eastern European countries decided to switch to the West German-developed [[PAL]] system.\n\nOther countries, notably the [[United Kingdom]] and [[Italy]], briefly experimented with SECAM before opting for PAL.\n\nSince late 2000s, SECAM is in the process of being phased out and replaced by [[Digital video broadcasting|DVB]].\n\n Some have argued that the primary motivation for the development of SECAM in France was to protect French television equipment manufacturers.<ref>Crane, R. J. (1979). The Politics of International Standards: France and the Color TV War, Ablex Publishing Corporation.</ref> However, incompatibility had started with the earlier unusual decision to adopt positive [[video modulation]] for French broadcast signals. The earlier systems [[CCIR System A|System A]] and the 819-line systems were the only other systems to use positive video modulation. In addition, SECAM development predates PAL. NTSC was considered undesirable in Europe because of its tint problem requiring an additional [[tint control|control]], which SECAM and PAL solved. Nonetheless, SECAM was partly developed for reasons of national pride. Henri de France's personal [[charisma]] and ambition may have been a contributing factor. PAL was developed by [[Telefunken]], a German company, and in the post-war [[Charles de Gaulle|De Gaulle]] era there would have been much political resistance to dropping a French-developed system and adopting a German-developed one instead.{{Citation needed|date=March 2007}}\n\nUnlike some other manufacturers, the company where SECAM was invented, [[Technicolor SA|Technicolor]] (known as Thomson until 2010), still sells television sets worldwide under different brands; this may be due in part to the legacy of SECAM. Thomson bought the company that developed PAL, Telefunken, and today even co-owns the [[RCA]] brand - RCA being the creator of NTSC. Thomson also co-authored the [[ATSC standards]] which are used for American [[high-definition television]].\n\n The standard spread from France to its former [[French colonial empire| African colonies]]. The system was also selected as the standard for color in the [[Soviet Union]], which began broadcasts shortly after the French, and remained in use in most of [[Commonwealth of Independent States|those countries]] that were once part of the Soviet Union. Other countries that selected this standard are Zaire, Tunisia, Surinam, Morocco, Monaco, Lebanon, C\u00f4te d'Ivoire, Hungary, Haiti, Greece and Egypt.<ref>{{Cite web|title=Samsung TV - PAL / NTSC / SECAM Countries List {{!}} Samsung Support CA|url=https://www.samsung.com/ca/support/tv-audio-video/can-i-use-my-tv-in-another-country/|access-date=2020-10-18|website=Samsung ca|language=en-CA}}</ref>\n\nThe adoption of SECAM in Eastern Europe has been attributed to [[Cold War]] political machinations.  According to this explanation, East German political authorities were well aware of West German television's popularity and adopted SECAM rather than the PAL encoding used in [[West Germany]].<ref>{{Cite book|last=Glaubitz|first=Gerald|title=Die PAL-SECAM-Kontroverse in der DDR: Die politisch-ideologische Instrumentalisierung der Farbfernsehfrage durch den ostdeutschen Staat zwischen 1965 und 1969|publisher=GNT-Verlag|year=2004|isbn=978-3928186735|location=Diepholz|pages=}}</ref> This did not hinder mutual reception in black and white, because the underlying TV standards remained essentially the same in both parts of Germany. However, [[East Germany|East Germans]] responded by buying PAL decoders for their SECAM sets. Eventually, the government in East Berlin stopped paying attention to so-called "[[Republikflucht]] via Fernsehen", or "defection via television". Later East German\u2013produced TV sets, such as the [[:de:Chromat (Fernsehger\u00e4t)|RFT Chromat]], even included a dual standard PAL/SECAM decoder as an option.\n\nAnother explanation for the Eastern European adoption of SECAM, led by the Soviet Union, is that the Russians had extremely long distribution lines between broadcasting stations and transmitters.<ref>[https://books.google.com/books?id=bmtByFnNCOQC&pg=PA197 Colour Television for Europe, New Scientist, 23 July 1963]</ref> Long co-axial cables or microwave links can cause amplitude and phase variations, which do not affect SECAM signals.\n\nHowever, PAL and SECAM are just standards for the color sub carrier, used in conjunction with  [[Broadcast television systems#ITU standards|ITU television broadcast systems]] for the base monochrome signals, identified with letters such as M, B/G, D/K, and L.\n\nThese signals are much more important to compatibility than the color sub carriers are. They differ by [[Amplitude modulation|AM]] or [[Frequency modulation|FM]] sound modulation, signal [[Polarization (waves)|polarization]], relative frequencies within the channel, bandwidth, etc. For example, a PAL D/K TV set will be able to receive a SECAM D/K signal (although in black and white), while it will not be able to decode the sound of a PAL B/G signal. So even before SECAM came to Eastern European countries, most viewers (other than those in East Germany and Yugoslavia) could not have received Western programs. This, along with language issues, meant that in most countries monochrome-only reception did not pose a significant problem for the authorities."}},
{"article_title": "Stethoscope", "pageid": "28714", "revid": "1062784731", "timestamp": "2021-12-30T14:24:51Z", "history_paths": [["Stethoscope --- Introduction ---", "History"]], "categories": ["french inventions", "medical equipment", "medical testing equipment", "medical tests", "sound technology", "1816 introductions"], "heading_tree": {"Stethoscope --- Introduction ---": {"History": {}, "Current practice": {}, "Types": {"Acoustic": {}, "Electronic{{anchor|Digital Stethoscope|Electronic Stethoschope}}": {"Recording": {}}, "Fetal": {}, "Doppler": {}, "3D-printed": {}, "Esophageal": {}}, "Earpieces": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Stethoscope --- Introduction ---|History": "{{Anchor|history}}\n\n[[File:Laennecs stethoscope, c 1820. (9660576833).jpg|thumb|This early stethoscope belonged to Laennec. ([[Science Museum, London]])]]\n\n[[Image:H\u00f6rrohr Stethoskop Meyers 1890.jpg|thumb|right|Early stethoscopes]]\n\n[[File:Toraube2.jpg|thumb|180px|right|A [[Ludwig Traube (physician)|Traube]]-type stethoscope in ivory]]\n\nThe stethoscope was invented in [[France]] in 1816 by [[Ren\u00e9 Laennec]] at the [[Necker-Enfants Malades Hospital]] in [[Paris]].<ref name=Wade2008>{{cite journal|last1=Wade|first1=Nicholas J.|last2=Deutsch|first2=Diana|title=Binaural Hearing \u2013 Before and After the Stethophone|journal=Acoustics Today|date=July 2008|volume=4|issue=3|pages=16\u201327|doi=10.1121/1.2994724|url=http://acousticstoday.org/wp-content/uploads/2017/07/Article_2of3_from_ATCODK_4_3.pdf}}</ref><ref>{{cite book |last=Laennec |first=Ren\u00e9 |title=De l'auscultation m\u00e9diate ou trait\u00e9 du diagnostic des maladies des poumon et du coeur |location=Paris |publisher=Brosson & Chaud\u00e9 |year= 1819 |url=https://books.google.com/books?id=TtTTeKls2bUC&pg=PR5 }}</ref><ref name="Laennec_Forbes_translation">'Laennec, R. T. H.;  Forbes, John, Sir, ''[https://books.google.com/books?id=a1pBAQAAIAAJ&lpg=PR23&pg=PR1#v=onepage&q&f=false A Treatise on the Diseases of the Chest and on Mediate Auscultation]'' (1835). New York : Samuel Wood & Sons; Philadelphia : Desilver, Thomas & Co. .</ref> It consisted of a wooden tube and was [[monaural]]. Laennec invented the stethoscope because he was not comfortable placing his ear directly onto a woman's chest to listen to her heart.<ref>{{cite journal|title=Rene Theophile Hyacinthe La\u00ebnnec (1781\u20131826): The Man Behind the Stethoscope|author=Roguin A|date=September 2006|pmc=1570491|pmid=17048358|volume=4|issue=3|pages=230\u20135|journal=Clin Med Res|doi=10.3121/cmr.4.3.230}}</ref><ref name="picard-victorian-london">{{cite book|last1=Picard|first1=Liza|author-link1=Liza Picard|title=Victorian London: the life of a city, 1840\u20131870|date=2005|publisher=Weidenfeld & Nicolson|location=London|isbn=978-0297847335|language=En}}</ref>{{rp|186}} He observed that a rolled piece of paper, placed between the individual's chest and his ear, could amplify heart sounds without requiring physical contact.<ref>{{Cite book|title=Mending Bodies, Saving Souls|last=Risse|first=Guenter|publisher=Oxford University Press|year=1999|isbn=978-0-19-505523-8|location=Oxford|pages=316}}</ref> Laennec's device was similar to the common [[ear trumpet]], a historical form of hearing aid; indeed, his invention was almost indistinguishable in structure and function from the trumpet, which was commonly called a "microphone". Laennec called his device the "stethoscope"<ref name="Foreign_Medicine_and_Surgery_1820">{{Citation |year=1820 |title=Laennec's new system of diagnosis |journal=The Quarterly Journal of Foreign Medicine and Surgery and of the Sciences Connected with Them |volume=2 |pages=51\u201368 |url=https://books.google.com/books?id=LNVLAAAAYAAJ&q=stethoscope&pg=PA58 |postscript=.}}</ref> (''[[wikt:stetho-#Prefix|stetho-]]'' + ''[[wikt:-scope#Suffix|-scope]]'', "chest scope"), and he called its use "[[wikt:mediate#Adjective|mediate]] auscultation", because it was [[auscultation]] with a tool intermediate between the individual's body and the physician's ear. (Today the word ''auscultation'' denotes all such listening, mediate or not.) The first flexible stethoscope of any sort may have been a binaural instrument with articulated joints not very clearly described in 1829.<ref>Wilks, p. 490, cites Comins, "A flexible stethoscope", ''Lancet'' 29 August 1829.</ref> In 1840, [[Golding Bird]] described a stethoscope he had been using with a flexible tube. Bird was the first to publish a description of such a stethoscope, but he noted in his paper the prior existence of an earlier design (which he thought was of little utility) which he described as the snake ear trumpet. Bird's stethoscope had a single earpiece.<ref>Samuel Wilks, "Evolution of the stethoscope", ''Popular Science'', '''vol. 22''', no. 28, pp. 488\u201391, Feb 1883 {{ISSN|0161-7370}}.<br />Golding Bird, [https://books.google.com/books?id=9FXVoGcVJygC&pg=PA440#v=onepage&q&f=true "Advantages presented by the employment of a stethoscope with a flexible tube"], ''London Medical Gazette'', '''vol. 1''', pp. 440\u201312, 11 December 1840.</ref>\n\nIn 1851, Irish physician Arthur Leared invented a binaural stethoscope, and in 1852, George Philip Cammann perfected the design of the stethoscope instrument (that used both ears) for commercial production, which has become the standard ever since. Cammann also wrote a major treatise on diagnosis by auscultation, which the refined binaural stethoscope made possible. By 1873, there were descriptions of a differential stethoscope that could connect to slightly different locations to create a slight stereo effect, though this did not become a standard tool in clinical practice.\n\n[[Somerville Scott Alison]] described his invention of the '''stethophone''' at the Royal Society in 1858; the stethophone had two separate bells, allowing the user to hear and compare sounds derived from two discrete locations.  This was used to do definitive studies on binaural hearing and [[auditory processing]] that advanced knowledge of [[sound localization]] and eventually lead to an understanding of [[binaural fusion]].<ref name=Wade2008/>\n\nThe medical historian [[Jacalyn Duffin]] has argued that the invention of the stethoscope marked a major step in the redefinition of disease from being a bundle of symptoms, to the current sense of a disease as a problem with an anatomical system even if there are no observable symptoms. This re-conceptualization occurred in part, Duffin argues, because prior to stethoscopes, there were no non-lethal instruments for exploring internal anatomy.<ref>{{cite web|last=Duffin|first=Jacalyn|title=Big Ideas: Jacalyn Duffin on the History of the Stethoscope|url=http://ww3.tvo.org/video/182217/jacalyn-duffin-history-stethoscope|publisher=TVO|access-date=28 November 2012}}</ref>\n\nRappaport and Sprague designed a new stethoscope in the 1940s, which became the standard by which other stethoscopes are measured, consisting of two sides, one of which is used for the respiratory system, the other for the cardiovascular system. The Rappaport-Sprague was later made by [[Hewlett-Packard]]. HP's medical products division was spun off as part of Agilent Technologies, Inc., where it became Agilent Healthcare. Agilent Healthcare was purchased by [[Philips]] which became Philips Medical Systems, before the walnut-boxed, $300, original Rappaport-Sprague stethoscope was finally abandoned ca. 2004, along with Philips' brand (manufactured by Andromed, of Montreal, Canada) electronic stethoscope model. The Rappaport-Sprague model stethoscope was heavy and short ({{convert|18|-|24|in|cm|abbr=on}}) with an antiquated appearance recognizable by their two large independent latex rubber tubes connecting an exposed leaf-spring-joined pair of opposing F-shaped chrome-plated brass binaural ear tubes with a dual-head chest piece.\n[[File:Early flexible stethoscopes.jpg|thumb|left|Early flexible tube stethoscopes. Golding Bird's instrument is on the left. The instrument on the right is the stethophone.<ref name=Wade2008/>]]\nSeveral other minor refinements were made to stethoscopes until, in the early 1960s, [[David Littmann]], a [[Harvard Medical School]] professor, created a new stethoscope that was lighter than previous models and had improved acoustics.<ref>{{cite web |title=History of Littmann Stethoscopes at a glance |publisher=3M.com |url= http://solutions.3m.com/wps/portal/3M/en_US/Littmann/stethoscope/products/history/ |access-date=2010-01-25}}</ref><ref>{{US patent|3108652}}</ref> In the late 1970s, 3M-Littmann introduced the tunable diaphragm: a very hard (G-10) glass-epoxy resin diaphragm member with an overmolded silicone flexible acoustic surround which permitted increased excursion of the diaphragm member in a Z-axis with respect to the plane of the sound collecting area.<ref>{{US patent|3951230}}</ref> The left shift to a lower resonant frequency increases the volume of some low frequency sounds due to the longer waves propagated by the increased excursion of the hard diaphragm member suspended in the concentric accountic surround. Conversely, restricting excursion of the diaphragm by pressing the stethoscope diaphragm surface firmly against the anatomical area overlying the physiological sounds of interest, the acoustic surround could also be used to dampen excursion of the diaphragm in response to "z"-axis pressure against a concentric fret. This raises the frequency bias by shortening the wavelength to auscultate a higher range of physiological sounds.\n\nIn 1999, Richard Deslauriers patented the first external noise reducing stethoscope, the DRG Puretone. It featured two parallel lumens containing two steel coils which dissipated infiltrating noise as inaudible heat energy. The steel coil "insulation" added .30 lb to each stethoscope. In 2005, DRG's diagnostics division was acquired by TRIMLINE Medical Products.<ref>{{cite web |url=http://www.trimline.us |title=TRIMLINE Medical Products |access-date=2010-01-25}}</ref>{{Failed verification|date=February 2019}}"}},
{"article_title": "Short Message Peer-to-Peer", "pageid": "28904", "revid": "1049989549", "timestamp": "2021-10-15T03:28:32Z", "history_paths": [["Short Message Peer-to-Peer --- Introduction ---", "History"]], "categories": ["gsm standard", "mobile technology", "network protocols"], "heading_tree": {"Short Message Peer-to-Peer --- Introduction ---": {"History": {}, "Operation": {"Versions": {}}, "PDU format (after version 3.4)": {"PDU header": {}}, "Example": {"PDU header": {}, "PDU body": {}}, "Quirks": {"No data_coding for GSM 7-bit default alphabet": {}, "Not standardized meaning of data_coding0": {}, "Unclear support for Shift-JIS encoding": {}, "Incompatibility of submit_sm_resp between SMPP versions": {}, "Message ID in SMPP 3.3 SMSC Delivery Receipts": {}}, "Extensibility, compatibility and interoperability": {}, "Security": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Short Message Peer-to-Peer --- Introduction ---|History": "SMPP (Short Message Peer-to-Peer) was originally designed by [[Aldiscon]], a small [[Ireland|Irish]] company that was later acquired by [[Logica]] (since 2016, after a number of changes [[Mavenir]]).  The protocol was originally created by a developer, Ian J Chambers, to test the functionality of the [[short message service center|SMSC]] without using SS7 test equipment to submit messages. In 1999, Logica formally handed over SMPP to the SMPP Developers Forum, later renamed as The SMS Forum and now disbanded. As part of the original handover terms, SMPP ownership has now returned to Mavenir due to the disbanding of the SMS Forum.\n\nTo date, SMPP development is suspended and SMS Forum is disbanded. From the SMS Forum website:\n\n<blockquote>July 31, 2007 - The SMS Forum, a non-profit organization with a mission to develop, foster and promote SMS (short message service) to the benefit of the global wireless industry will disband by July 27, 2007</blockquote>\n\nA press release, attached to the news, used to warn that site will be suspended soon. In spite of this, the site was mostly functioning and specifications could be downloaded (as of 31 January 2012). As of 12 April 2021, the website owner has changed and the specifications can be download from mirror sites only.\n\nIn 1995 the [[ETSI]] has included the SMPP protocol into the technical report TR 03.39.<ref>{{cite book|url=https://books.google.com/books?id=YPgfNaoYHUsC|title=Short Message Service (SMS): The Creation of Personal Global Text Messaging|page=112|author=Friedhelm Hillebrand|publisher=[[Wiley (publisher)|Wiley]]|year=2010|isbn=978-0-470-68865-6}}</ref>"}},
{"article_title": "Semantic Web", "pageid": "29123", "revid": "1061181901", "timestamp": "2021-12-20T04:07:20Z", "history_paths": [["Semantic Web --- Introduction ---"]], "categories": ["semantic web", "emerging technologies", "internet ages", "knowledge engineering", "web services"], "heading_tree": {"Semantic Web --- Introduction ---": {"Example": {}, "Background": {"Limitations of HTML": {}, "Semantic Web solutions": {}, "Web 3.0": {"Semantic Web": {}, "Decentralization": {}}}, "Challenges": {}, "Standards": {"Components": {}, "Current state of standardization": {}}, "Applications": {}, "Skeptical reactions": {"Practical feasibility": {}, "Censorship and privacy": {}, "Doubling output formats": {}}, "Research activities on corporate applications": {"Future of applications": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Semantic Web --- Introduction ---": "{{Short description|Extension of the Web to facilitate data exchange}}\n{{About|the concept for an Internet based around machine-readability and interoperability standards|the concept for a decentralized Internet|Web3}}\n{{Use American English|date=December 2021}}\n\n{{Semantics}}\nThe '''Semantic Web''' (sometimes known as '''Web 3.0''') is an extension of the [[World Wide Web]] through standards set by the [[World Wide Web Consortium]] (W3C).<ref>{{cite web|url=http://www.dblab.ntua.gr/~bikakis/XML%20and%20Semantic%20Web%20W3C%20Standards%20Timeline-History.pdf|title=XML and Semantic Web W3C Standards Timeline|date=2012-02-04}}</ref> The goal of the Semantic Web is to make [[Internet]] data machine-readable. \n\nTo enable the encoding of [[semantics]] with the data, technologies such as [[Resource Description Framework]] (RDF)<ref>{{cite web|url=http://www.w3.org/TR/rdf-syntax-grammar/ | title=World Wide Web Consortium (W3C), "RDF/XML Syntax Specification (Revised)", 10 Feb. 2004.}}</ref> and [[Web Ontology Language]] (OWL)<ref>{{cite web|url=http://www.w3.org/TR/owl-features/ | title=World Wide Web Consortium (W3C), "OWL Web Ontology Language Overview", W3C Recommendation, 10 Feb. 2004.}}</ref> are used. These technologies are used to formally represent [[metadata]]. For example, [[Ontology (information science)|ontology]] can describe [[concept]]s, relationships between [[Entity\u2013relationship model|entities]], and categories of things. These embedded semantics offer significant advantages such as reasoning over data and operating with heterogeneous data sources.<ref>{{cite journal|url=https://purkh.com/index.php/tocomp/article/view/33|last=Chung|first=Seung-Hwa|title=The MOUSE approach: Mapping Ontologies using UML for System Engineers|date=2018|journal=Computer Reviews Journal|issn=2581-6640|pages=8\u201329}}</ref>\n\nThese standards promote common data formats and exchange protocols on the Web, fundamentally the RDF. According to the W3C, "The Semantic Web provides a common framework that allows data to be shared and reused across application, enterprise, and community boundaries."<ref name="W3C-SWA" /> The Semantic Web is therefore regarded as an integrator across different content and information applications and systems.\n\nThe term was coined by [[Tim Berners-Lee]] for a web of data (or '''data web''')<ref>{{cite web|url=https://www.bloomberg.com/news/articles/2007-04-09/q-and-a-with-tim-berners-leebusinessweek-business-news-stock-market-and-financial-advice|title=Q&A with Tim Berners-Lee, Special Report |website=businessweek.com|access-date=14 April 2018}}</ref> that can be processed by machines<ref name="Berners-Lee"/>\u2014that is, one in which much of the [[meaning (linguistics)|meaning]] is [[machine-readable data|machine-readable]]. While its critics have questioned its feasibility, proponents argue that applications in [[Library science|library]] and [[information science]], industry, [[biology]] and [[human science]]s research have already proven the validity of the original concept.<ref>{{cite magazine |access-date=February 24, 2010 |url=http://www.thefigtrees.net/lee/sw/sciam/semantic-web-in-action |title=The Semantic Web in Action |magazine=Scientific American |date=May 1, 2007 |author=Lee Feigenbaum}}</ref>\n\nBerners-Lee originally expressed his vision of the Semantic Web in 1999 as follows:\n{{quote|I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web \u2013 the content, links, and transactions between people and computers. A "Semantic Web", which makes this possible, has yet to emerge, but when it does, the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The "[[intelligent agent]]s" people have touted for ages will finally materialize.<ref>{{cite book |last=Berners-Lee |first=Tim |author-link=Tim Berners-Lee |author2=Fischetti, Mark |title=Weaving the Web |publisher=[[HarperSanFrancisco]] |year=1999 |pages=[https://archive.org/details/isbn_9780062515872/page/ chapter 12] |isbn=978-0-06-251587-2 |no-pp=true |title-link=Tim Berners Lee#Weaving the Web}}</ref>}}\n\nThe 2001 ''[[Scientific American]]'' article by Berners-Lee, [[James Hendler|Hendler]], and [[Ora Lassila|Lassila]] described an expected evolution of the existing Web to a Semantic Web.<ref>{{cite magazine |access-date=March 13, 2008 |url=https://pdfs.semanticscholar.org/566c/1c6bd366b4c9e07fc37eb372771690d5ba31.pdf |archive-url=https://web.archive.org/web/20171010210556/https://pdfs.semanticscholar.org/566c/1c6bd366b4c9e07fc37eb372771690d5ba31.pdf |url-status=dead |archive-date=October 10, 2017 |title=The Semantic Web |magazine=Scientific American |date=May 17, 2001 |author=Berners-Lee, Tim |s2cid=32015696}}</ref> In 2006, Berners-Lee and colleagues stated that: "This simple idea\u2026remains largely unrealized".<ref>{{cite web\n | url=http://eprints.ecs.soton.ac.uk/12614/1/Semantic_Web_Revisted.pdf\n | title=The Semantic Web Revisited\n | access-date=April 13, 2007\n |author1=Nigel Shadbolt |author2=Wendy Hall |author3=Tim Berners-Lee | year=2006\n | work=[[IEEE]] Intelligent Systems}}</ref>\nIn 2013, more than four million Web domains (out of roughly 250 million total) contained Semantic Web markup.<ref>{{cite web\n | url=http://iswc2013.semanticweb.org/content/keynote-ramanathan-v-guha.html\n | title=Light at the End of the Tunnel\n | access-date=March 8, 2015\n | author=Ramanathan V. Guha\n | year=2013\n | work=[[International Semantic Web Conference]] 2013 Keynote}}</ref>\n\n In the following example, the text "Paul Schuster was born in Dresden" on a website will be annotated, connecting a person with their place of birth. The following [[HTML]] fragment shows how a small graph is being described, in [[RDFa]]-syntax using a [[schema.org]] vocabulary and a [[Wikidata]] ID:\n<syntaxhighlight lang="html5">\n<div vocab="https://schema.org/" typeof="Person">\n  <span property="name">Paul Schuster</span> was born in\n  <span property="birthPlace" typeof="Place" href="https://www.wikidata.org/entity/Q1731">\n    <span property="name">Dresden</span>.\n  </span>\n</div>\n</syntaxhighlight>\n[[File:RDF example.svg|framed|{{anchor|graph1}}Graph resulting from the RDFa example]]{{clear}}\n\nThe example defines the following five [[Semantic triple|triples]] (shown in [[Turtle (syntax)|Turtle]] syntax). Each triple represents one edge in the resulting graph: the first element of the triple (the ''subject'') is the name of the node where the edge starts, the second element (the ''predicate'') the type of the edge, and the last and third element (the ''object'') either the name of the node where the edge ends or a literal value (e.g. a text, a number, etc.).\n<div class="plainlinks">\n _:a <https://www.w3.org/1999/02/22-rdf-syntax-ns#type> <https://schema.org/Person> .\n _:a <https://schema.org/name> "Paul Schuster" .\n _:a <https://schema.org/birthPlace> <https://www.wikidata.org/entity/Q1731> .\n <https://www.wikidata.org/entity/Q1731> <https://schema.org/itemtype> <https://schema.org/Place> .\n <https://www.wikidata.org/entity/Q1731> <https://schema.org/name> "Dresden" .\n</div>\n\nThe triples result in the graph shown in [[#graph1|the given figure]].\n\n[[File:RDF example extended.svg|framed|Graph resulting from the RDFa example, enriched with further data from the Web]]\n\nOne of the advantages of using [[Uniform Resource Identifier|Uniform Resource Identifiers (URIs)]] is that they can be dereferenced using the [[HTTP]] protocol. According to the so-called [[Linked Open Data]] principles, such a dereferenced URI should result in a document that offers further data about the given URI. In this example, all URIs, both for edges and nodes (e.g. {{code|http://schema.org/Person}}, {{code|http://schema.org/birthPlace}}, {{code|http://www.wikidata.org/entity/Q1731}}) can be dereferenced and will result in further RDF graphs, describing the URI, e.g. that Dresden is a city in Germany, or that a person, in the sense of that URI, can be fictional.\n\nThe second graph shows the previous example, but now enriched with a few of the triples from the documents that result from dereferencing {{code|https://schema.org/Person}} (green edge) and {{code|https://www.wikidata.org/entity/Q1731}} (blue edges).\n\nAdditionally to the edges given in the involved documents explicitly, edges can be automatically inferred: the triple\n<div class="plainlinks">\n _:a <https://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://schema.org/Person> .\n</div>\n\nfrom the original RDFa fragment and the triple\n<div class="plainlinks">\n <https://schema.org/Person> <http://www.w3.org/2002/07/owl#equivalentClass> <http://xmlns.com/foaf/0.1/Person> .\n</div>\n\nfrom the document at {{code|https://schema.org/Person}} (green edge in the figure) allow to infer the following triple, given [[Web Ontology Language|OWL]] semantics (red dashed line in the second Figure):\n<div class="plainlinks">\n _:a <https://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> .\n</div>\n\n {{Further|Semantic network#History}}\nThe concept of the [[semantic network]] model was formed in the early 1960s by researchers such as the [[Cognitive science|cognitive scientist]] [[Allan M. Collins]], [[Linguistics|linguist]] M. Ross Quillian and [[psychologist]] [[Elizabeth F. Loftus]] as a form to represent semantically structured knowledge. When applied in the context of the modern internet, it extends the network of [[hyperlink]]ed human-readable [[web pages]] by inserting machine-readable metadata about pages and how they are related to each other.  This enables [[Web crawler|automated agents]] to access the Web more intelligently and perform more tasks on behalf of users. The term "Semantic Web" was coined by [[Tim Berners-Lee]],<ref name="Berners-Lee"/> the inventor of the World Wide Web and director of the World Wide Web Consortium ("[[W3C]]"), which oversees the development of proposed Semantic Web standards. He defines the Semantic Web as "a web of data that can be processed directly and indirectly by machines".\n\nMany of the technologies proposed by the W3C already existed before they were positioned under the W3C umbrella. These are used in various contexts, particularly those dealing with information that encompasses a limited and defined domain, and where sharing data is a common necessity, such as scientific research or data exchange among businesses. In addition, other technologies with similar goals have emerged, such as [[microformat]]s.\n\n Many files on a typical computer can also be loosely divided into human-readable documents and machine-readable data. Documents like mail messages, reports, and brochures are read by humans. Data, such as calendars, address books, playlists, and spreadsheets are presented using an application program that lets them be viewed, searched, and combined.\n\nCurrently, the World Wide Web is based mainly on documents written in [[Hypertext Markup Language]] (HTML), a markup convention that is used for coding a body of text interspersed with multimedia objects such as images and interactive forms. Metadata tags provide a method by which computers can categorize the content of web pages. In the examples below, the field names "keywords", "description" and "author" are assigned values such as "computing", and "cheap widgets for sale" and "John Doe".\n\n<syntaxhighlight lang="html4strict">\n<meta name="keywords" content="computing, computer studies, computer" />\n<meta name="description" content="Cheap widgets for sale" />\n<meta name="author" content="John Doe" />\n</syntaxhighlight>\n\nBecause of this metadata tagging and categorization, other computer systems that want to access and share this data can easily identify the relevant values.\n\nWith HTML and a tool to render it (perhaps [[web browser]] software, perhaps another [[user agent]]), one can create and present a page that lists items for sale. The HTML of this catalog page can make simple, document-level assertions such as "this document's title is 'Widget Superstore{{'"}}, but there is no capability within the HTML itself to assert unambiguously that, for example, item number X586172 is an Acme Gizmo with a retail price of \u20ac199, or that it is a consumer product. Rather, HTML can only say that the span of text "X586172" is something that should be positioned near "Acme Gizmo" and "\u20ac199", etc. There is no way to say "this is a catalog" or even to establish that "Acme Gizmo" is a kind of title or that "\u20ac199" is a price. There is also no way to express that these pieces of information are bound together in describing a discrete item, distinct from other items perhaps listed on the page.\n\n[[Semantic HTML]] refers to the traditional HTML practice of markup following intention, rather than specifying layout details directly. For example, the use of {{tag|em|o}} denoting "emphasis" rather than {{tag|i|o}}, which specifies [[italics]]. Layout details are left up to the browser, in combination with [[Cascading Style Sheets]]. But this practice falls short of specifying the semantics of objects such as items for sale or prices.\n\nMicroformats extend HTML syntax to create [[Machine-readable data|machine-readable]] semantic markup about objects including people, organizations, events and products.<ref>{{cite book |last=Allsopp |first=John |title=Microformats: Empowering Your Markup for Web 2.0 |date=March 2007 |publisher=[[Apress|Friends of ED]] |isbn=978-1-59059-814-6 |page=[https://archive.org/details/isbn_9781590598146/page/368 368] |url-access=registration |url=https://archive.org/details/isbn_9781590598146/page/368 }}</ref> Similar initiatives include [[RDFa]], [[Microdata (HTML)|Microdata]] and [[Schema.org]].\n\n The Semantic Web takes the solution further. It involves publishing in languages specifically designed for data: [[Resource Description Framework]] (RDF), [[Web Ontology Language]] (OWL), and Extensible Markup Language ([[XML]]). HTML describes documents and the links between them. RDF, OWL, and XML, by contrast, can describe arbitrary things such as people, meetings, or airplane parts.\n\nThese technologies are combined in order to provide descriptions that supplement or replace the content of Web documents. Thus, content may manifest itself as descriptive data stored in Web-accessible [[database]]s,<ref>Artem Chebotko and Shiyong Lu, "Querying the Semantic Web: An Efficient Approach Using Relational Databases", [[LAP Lambert Academic Publishing]], {{ISBN|978-3-8383-0264-5}}, 2009.</ref> or as markup within documents (particularly, in Extensible HTML ([[XHTML]]) interspersed with XML, or, more often, purely in XML, with layout or rendering cues stored separately). The machine-readable descriptions enable content managers to add meaning to the content, i.e., to describe the structure of the knowledge we have about that content. In this way, a machine can process knowledge itself, instead of text, using processes similar to human [[deductive reasoning]] and [[inference]], thereby obtaining more meaningful results and helping computers to perform automated information gathering and research.\n\nAn example of a tag that would be used in a non-semantic web page:\n<syntaxhighlight lang="xml">\n<item>blog</item>\n</syntaxhighlight>\n\nEncoding similar information in a semantic web page might look like this:\n<syntaxhighlight lang="xml">\n<item rdf:about="https://example.org/semantic-web/">Semantic Web</item>\n</syntaxhighlight>\n\nTim Berners-Lee calls the resulting network of [[Linked Data]] the [[Giant Global Graph]], in contrast to the HTML-based World Wide Web. Berners-Lee posits that if the past was document sharing, the future is [[data sharing]]. His answer to the question of "how" provides three points of instruction. One, a URL should point to the data. Two, anyone accessing the URL should get data back. Three, relationships in the data should point to additional URLs with data.\n\n \n Tim Berners-Lee has described the Semantic Web as a component of Web 3.0.<ref>{{cite news\n | url=https://www.nytimes.com/2006/05/23/technology/23iht-web.html\n | title=A 'more revolutionary' Web\n | date=23 May 2006\n | last=Shannon |first=Victoria \n | access-date=26 June 2006\n | work=[[International Herald Tribune]]}}</ref>\n\n{{quote|People keep asking what Web 3.0 is. I think maybe when you've got an overlay of [[scalable vector graphics]] \u2013 everything rippling and folding and looking misty \u2013 on [[Web 2.0]] and access to a semantic Web integrated across a huge space of data, you'll have access to an unbelievable data resource \u2026|Tim Berners-Lee, 2006}}\n\n"Semantic Web" is sometimes used as a synonym for "Web 3.0",<ref name="vvv">{{Cite web |url=http://www.tweakandtrick.com/2012/05/web-30.html |title=Introducing The Concept Of Web 3.0 |last=Sharma |first=Akhilesh |access-date=10 January 2017 |work=Tweak And Trick}}</ref> though the definition of each term varies. \n\n {{Main|Web3}}\n{{See also|Decentralization#Information technology}}\nWeb 3.0 has started to emerge as a movement away from the [[centralization]] of services like search, [[social media]] and [[Messaging apps|chat applications]] that are dependent on a single organization to function,<ref name="adw">{{Cite web |url=https://techcrunch.com/2016/10/09/a-decentralized-web-would-give-power-back-to-the-people-online/ |title=A decentralized web would give power back to the people online |last=Hodgson |first=Matthew |access-date=1 December 2016 |date=9 October 2016 |website=[[TechCrunch]] |publisher=AOL Inc}}</ref> and is described as "the next, post-[[Big Tech]] phase".<ref>{{Cite web|url=https://www.bloomberg.com/news/articles/2021-03-18/even-garbage-is-using-blockchain-now|access-date=2021-08-12|website=www.bloomberg.com}}</ref>\n\n''[[The Guardian|Guardian]]'' journalist [[John Harris (critic)|John Harris]] reviewed the {{nowrap|Web 3.0}} concept favorably in early 2019 and, in particular, work by Berners{{nbhyph}}Lee on a decentralization project called [[Solid (web decentralization project)|Solid]], based around personal data stores or "pods", over which individuals retain control.<ref name="harris-2019">\n{{cite news\n | last = Harris | first = John\n | title = Together we can thwart the big-tech data grab: here's how\n | date = 7 January 2019\n | work = [[The Guardian]]\n | location = London, United Kingdom\n | issn = 0261-3077\n | url = https://www.theguardian.com/commentisfree/2019/jan/07/big-tech-data-internet\n | access-date = 7 January 2019\n}}\n</ref>  Berners{{nbhyph}}Lee has formed a startup, Inrupt, to advance the idea and attract volunteer developers.<ref name="brooker-2018">\n{{cite web\n | last = Brooker | first = Katrina\n | title = Exclusive: Tim Berners-Lee tells us his radical new plan to upend the World Wide Web\n | date = 29 September 2018\n | work = [[Fast Company]]\n | location = USA\n | url = https://www.fastcompany.com/90243936/exclusive-tim-berners-lee-tells-us-his-radical-new-plan-to-upend-the-world-wide-web\n | access-date = 7 January 2019\n}}\n</ref><ref name="irupt-website">\n{{cite web\n | title = Home {{!}} inrupt\n | url = https://www.inrupt.com\n | website=Inrupt\n | access-date = 7 January 2019\n}}\n</ref>\n\n Some of the challenges for the Semantic Web include vastness, vagueness, uncertainty, inconsistency, and deceit. [[Automated reasoning system]]s will have to deal with all of these issues in order to deliver on the promise of the Semantic Web.\n* Vastness: The World Wide Web contains many billions of pages. The [[SNOMED CT]] [[medical terminology]] [[ontology (information science)|ontology]] alone contains 370,000 [[Class (computer programming)|class]] names, and existing technology has not yet been able to eliminate all semantically duplicated terms. Any [[Reasoning system|automated reasoning system]] will have to deal with truly huge inputs.\n* Vagueness: These are imprecise concepts like "young" or "tall". This arises from the vagueness of user queries, of concepts represented by content providers, of matching query terms to provider terms and of trying to combine different [[knowledge base]]s with overlapping but subtly different concepts. [[Fuzzy logic]] is the most common technique for dealing with vagueness.\n* Uncertainty: These are precise concepts with uncertain values. For example, a patient might present a set of symptoms that correspond to a number of different distinct diagnoses each with a different probability. [[Probabilistic logic|Probabilistic]] reasoning techniques are generally employed to address uncertainty.\n* Inconsistency: These are logical contradictions that will inevitably arise during the development of large ontologies, and when ontologies from separate sources are combined. Deductive reasoning fails catastrophically when faced with inconsistency, because [[Principle of explosion|"anything follows from a contradiction"]]. [[Defeasible reasoning]] and [[Paraconsistent logic|paraconsistent reasoning]] are two techniques that can be employed to deal with inconsistency.\n* Deceit: This is when the producer of the information is intentionally misleading the consumer of the information. [[Cryptography]] techniques are currently utilized to alleviate this threat. By providing a means to determine the information's integrity, including that which relates to the identity of the entity that produced or published the information, however [[credibility]] issues still have to be addressed in cases of potential deceit.\n\nThis list of challenges is illustrative rather than exhaustive, and it focuses on the challenges to the "unifying logic" and "proof" layers of the Semantic Web. The World Wide Web Consortium (W3C) Incubator Group for Uncertainty Reasoning for the World Wide Web<ref>{{Cite web|title=W3C Uncertainty Reasoning for the World Wide Web|url=https://www.w3.org/2005/Incubator/urw3/Overview.html|access-date=2021-05-14|website=www.w3.org}}</ref> (URW3-XG) final report lumps these problems together under the single heading of "uncertainty".<ref>{{cite web|url=http://www.w3.org/2005/Incubator/urw3/XGR-urw3-20080331/Overview.html|title=Uncertainty Reasoning for the World Wide Web|website=W3.org|access-date=20 December 2018}}</ref> Many of the techniques mentioned here will require extensions to the Web Ontology Language (OWL) for example to annotate conditional probabilities. This is an area of active research.<ref>{{cite journal |last=Lukasiewicz |first=Thomas |author2=Umberto Straccia |title=Managing uncertainty and vagueness in description logics for the Semantic Web |doi=10.1016/j.websem.2008.04.001 |volume=6 |issue=4 |journal=Web Semantics: Science, Services and Agents on the World Wide Web |pages=291\u2013308|year=2008 |url=http://faure.isti.cnr.it/~straccia/download/papers/JWS08/JWS08.pdf }}</ref>\n\n Standardization for Semantic Web in the context of Web 3.0 is under the care of W3C.<ref>{{cite web|url=http://www.w3.org/2001/sw/wiki/Main_Page|title=Semantic Web Standards|website=W3.org|access-date=14 April 2018}}</ref>\n\n The term "Semantic Web" is often used more specifically to refer to the formats and technologies that enable it.<ref name="W3C-SWA" /> The collection, structuring and recovery of linked data are enabled by technologies that provide a [[description logic|formal description]] of concepts, terms, and relationships within a given [[knowledge domain]]. These technologies are specified as W3C standards and include:\n* [[Resource Description Framework]] (RDF), a general method for describing information\n* [[RDF Schema]] (RDFS)\n* [[Simple Knowledge Organization System]] (SKOS)\n* [[SPARQL]], an RDF query language\n* [[Notation3]] (N3), designed with human readability in mind\n* [[N-Triples]], a format for storing and transmitting data\n* [[Turtle (syntax)|Turtle]] (Terse RDF Triple Language)\n* [[Web Ontology Language]] (OWL), a family of knowledge representation languages\n* [[Rule Interchange Format]] (RIF), a framework of web rule language dialects supporting rule interchange on the Web\n* [[JSON-LD|JavaScript Object Notation for Linked Data]] (JSON-LD), a JSON-based method to describe data\n* [[ActivityPub]], a generic way for client and server to communicate with each other. This is used by the popular decentralized social network [[Mastodon_(software)|Mastodon]].\n\n[[File:Semantic_web_stack.svg|frame |right |The [[Semantic Web Stack]]]]\n\nThe [[Semantic Web Stack]] illustrates the architecture of the Semantic Web. The functions and relationships of the components can be summarized as follows:<ref>{{cite web |url=http://www.w3.org/TR/owl-features/ |title=OWL Web Ontology Language Overview |date=February 10, 2004 |publisher=World Wide Web Consortium (W3C) |access-date=November 26, 2011}}</ref>\n* XML provides an elemental syntax for content structure within documents, yet associates no semantics with the meaning of the content contained within. XML is not at present a necessary component of Semantic Web technologies in most cases, as alternative syntaxes exist, such as [[Turtle (syntax)|Turtle]]. Turtle is a de-facto standard, but has not been through a formal standardization process.\n* [[W3C XML Schema|XML Schema]] is a language for providing and restricting the structure and content of elements contained within XML documents.\n* RDF is a simple language for expressing [[data model]]s, which refer to objects ("[[web resource]]s") and their relationships. An RDF-based model can be represented in a variety of syntaxes, e.g., [[RDF/XML]], N3, Turtle, and RDFa. RDF is a fundamental standard of the Semantic Web.<ref>{{cite web|url=http://www.w3.org/RDF/ | title=Resource Description Framework (RDF) | publisher=[[World Wide Web Consortium]]}}</ref><ref>{{cite book |last1=Allemang |first1=Dean |last2=Hendler |first2=James |last3=Gandon |first3=Fabien |title=Semantic Web for the Working Ontologist : Effective Modeling for Linked Data, RDFS, and OWL |date=August 3, 2020 |publisher=ACM Books; 3rd edition |location=[New York, NY, USA] |isbn=978-1450376143 |edition=Third}}</ref>\n* RDF Schema extends RDF and is a vocabulary for describing properties and classes of RDF-based resources, with semantics for generalized-hierarchies of such properties and classes.\n* OWL adds more vocabulary for describing properties and classes: among others, relations between classes (e.g. disjointness), cardinality (e.g. "exactly one"), equality, richer typing of properties, characteristics of properties (e.g. symmetry), and enumerated classes.\n* SPARQL is a protocol and query language for semantic web data sources.\n* RIF is the W3C Rule Interchange Format. It's an XML language for expressing Web rules that computers can execute. RIF provides multiple versions, called dialects. It includes a RIF Basic Logic Dialect (RIF-BLD) and RIF Production Rules Dialect (RIF PRD).\n\n Well-established standards:\n* [[Resource Description Framework|RDF]]\n* [[RDFS]]\n* [[Rule Interchange Format]] (RIF)\n* [[SPARQL]]\n* [[Unicode]]\n* [[Uniform Resource Identifier]]\n* Web Ontology Language (OWL)\n* [[XML]]\n\nNot yet fully realized:\n* Unifying Logic and Proof layers\n* [[Semantic Web Rule Language]] (SWRL)\n\n The intent is to enhance the [[usability]] and usefulness of the Web and its interconnected [[resource (computer science)|resources]] by creating [[semantic web service]]s, such as:\n* Servers that expose existing data systems using the RDF and SPARQL standards. Many converters to RDF exist from different applications.<ref>{{cite web|url=https://www.w3.org/wiki/ConverterToRdf|title=ConverterToRdf - W3C Wiki|website=W3.org|access-date=20 December 2018}}</ref> [[Relational database]]s are an important source. The [[Semantic web service|semantic web server]] attaches to the existing system without affecting its operation.\n* Documents "marked up" with semantic information (an [[Extensibility|extension]] of the HTML {{code|<meta>}} [[HTML element|tags]] used in today's Web pages to supply information for [[Web search engine]]s using [[web crawler]]s). This could be [[Artificial intelligence|machine-understandable]] information about the human-understandable content of the document (such as the creator, title, description, etc.) or it could be purely metadata representing a set of facts (such as resources and services elsewhere on the site). Note that ''anything'' that can be identified with a ''Uniform Resource Identifier'' (URI) can be described, so the semantic web can reason about animals, people, places, ideas, etc.  There are four semantic annotation formats that can be used in HTML documents; Microformat, RDFa, Microdata and [[JSON-LD]].<ref>{{Cite book|title = Mastering Structured Data on the Semantic Web: From HTML5 Microdata to Linked Open Data|last = Sikos|first = Leslie F.|publisher = Apress|year = 2015|isbn = 978-1-4842-1049-9|pages = 23}}</ref> Semantic markup is often generated automatically, rather than manually.\n* Common metadata vocabularies ([[Ontology (information science)|ontologies]]) and maps between vocabularies that allow document creators to know how to mark up their documents so that agents can use the information in the supplied metadata (so that ''Author'' in the sense of 'the Author of the page' won't be confused with ''Author'' in the sense of a book that is the subject of a book review).\n* Automated agents to perform tasks for users of the semantic web using this data.\n* Web-based services (often with agents of their own) to supply information specifically to agents, for example, a [[Trust service]] that an agent could ask if some online store has a history of poor service or [[spamming]].\n\nSuch services could be useful to public search engines, or could be used for [[knowledge management]] within an organization.  Business applications include:\n* Facilitating the integration of information from mixed sources\n* Dissolving ambiguities in corporate terminology\n* Improving [[information retrieval]] thereby reducing [[information overload]] and increasing the refinement and precision of the data retrieved<ref>Omar Alonso and Hugo Zaragoza. 2008. Exploiting semantic annotations in information retrieval: ESAIR '08. SIGIR Forum 42, 1 (June 2008), 55\u201358. {{doi|10.1145/1394251.1394262}}</ref><ref>Jaap Kamps, [[Jussi Karlgren]], and Ralf Schenkel. 2011. Report on the third workshop on exploiting semantic annotations in information retrieval (ESAIR). SIGIR Forum 45, 1 (May 2011), 33\u201341. {{doi|10.1145/1988852.1988858}}</ref><ref>Jaap Kamps, [[Jussi Karlgren]], Peter Mika, and Vanessa Murdock. 2012. Fifth workshop on exploiting semantic annotations in information retrieval: ESAIR '12). In Proceedings of the 21st ACM international conference on information and knowledge management (CIKM '12). ACM, New York, NY, USA, 2772\u20132773. {{doi|10.1145/2396761.2398761}}</ref><ref>Omar Alonso, Jaap Kamps, and [[Jussi Karlgren]]. 2015. Report on the Seventh Workshop on Exploiting Semantic Annotations in Information Retrieval (ESAIR '14). SIGIR Forum 49, 1 (June 2015), 27\u201334. {{doi|10.1145/2795403.2795412}}</ref>\n* Identifying relevant information with respect to a given domain<ref>{{cite journal\n| ref         = Kuriakose2009\n| last        = Kuriakose\n| first       = John\n|date=September 2009\n| title       = Understanding and Adopting Semantic Web Technology\n| journal     = Cutter IT Journal\n| volume      = 22\n| issue       = 9\n| pages       = 10\u201318\n| publisher   = CUTTER INFORMATION CORP.\n  |url=http://www.cutter.com/itjournal/fulltext/2009/09/itj0909b.html\n}}</ref>\n* Providing decision making support\n\nIn a corporation, there is a closed group of users and the management is able to enforce company guidelines like the adoption of specific ontologies and use of [[semantic annotation]]. Compared to the public Semantic Web there are lesser requirements on [[scalability]] and the information circulating within a company can be more trusted in general; privacy is less of an issue outside of handling of customer data.\n\n  Critics question the basic feasibility of a complete or even partial fulfillment of the Semantic Web, pointing out both difficulties in setting it up and a lack of general-purpose usefulness that prevents the required effort from being invested. In a 2003 paper, Marshall and Shipman point out the cognitive overhead inherent in formalizing knowledge, compared to the authoring of traditional web [[hypertext]]:<ref name="which">{{cite conference |title=Which semantic web? |last1=Marshall |first1=Catherine C. |last2=Shipman |first2=Frank M. |conference=Proc. ACM Conf. on Hypertext and Hypermedia |pages=57\u201366 |year=2003 |url=http://www.csdl.tamu.edu/~marshall/ht03-sw-4.pdf}}</ref>\n\n{{quote|While learning the basics of HTML is relatively straightforward, learning a knowledge representation language or tool requires the author to learn about the representation's methods of abstraction and their effect on reasoning. For example, understanding the class-instance relationship, or the superclass-subclass relationship, is more than understanding that one concept is a \u201ctype of\u201d another concept. [\u2026] These abstractions are taught to computer scientists generally and knowledge engineers specifically but do not match the similar natural language meaning of being a "type of" something. Effective use of such a formal representation requires the author to become a skilled knowledge engineer in addition to any other skills required by the domain. [\u2026] Once one has learned a formal representation language, it is still often much more effort to express ideas in that representation than in a less formal representation [\u2026]. Indeed, this is a form of programming based on the declaration of semantic data and requires an understanding of how reasoning algorithms will interpret the authored structures.}}\n\nAccording to Marshall and Shipman, the [[tacit knowledge|tacit]] and changing nature of much knowledge adds to the [[knowledge engineering]] problem, and limits the Semantic Web's applicability to specific domains. A further issue that they point out are domain- or organization-specific ways to express knowledge, which must be solved through community agreement rather than only technical means.{{r|which}} As it turns out, specialized communities and organizations for intra-company projects have tended to adopt semantic web technologies greater than peripheral and less-specialized communities.<ref name="Herman000">{{cite conference |url=http://www.w3.org/2007/Talks/0424-Stavanger-IH/Slides.pdf |title=State of the Semantic Web |access-date=July 26, 2007 |author=Ivan Herman |year=2007 |conference=Semantic Days 2007}}</ref> The practical constraints toward adoption have appeared less challenging where domain and scope is more limited than that of the general public and the World-Wide Web.{{r|Herman000}}\n\nFinally, Marshall and Shipman see pragmatic problems in the idea of ([[Knowledge Navigator]]-style) intelligent agents working in the largely manually curated Semantic Web:{{r|which}}\n\n{{quote|In situations in which user needs are known and distributed information resources are well described, this approach can be highly effective; in situations that are not foreseen and that bring together an unanticipated array of information resources, the Google approach is more robust. Furthermore, the Semantic Web relies on inference chains that are more brittle; a missing element of the chain results in a failure to perform the desired action, while the human can supply missing pieces in a more Google-like approach. [\u2026] cost-benefit tradeoffs can work in favor of specially-created Semantic Web metadata directed at weaving together sensible well-structured domain-specific information resources; close attention to user/customer needs will drive these federations if they are to be successful.}}\n\n[[Cory Doctorow]]'s critique ("[[metacrap]]") is from the perspective of human behavior and personal preferences. For example, people may include spurious metadata into Web pages in an attempt to mislead Semantic Web engines that naively assume the metadata's veracity. This phenomenon was well known with metatags that fooled the [[Altavista]] ranking algorithm into elevating the ranking of certain Web pages: the Google indexing engine specifically looks for such attempts at manipulation. [[Peter G\u00e4rdenfors]] and [[Timo Honkela]] point out that logic-based semantic web technologies cover only a fraction of the relevant phenomena related to semantics.<ref name="Gardenfors04">{{Cite book\n | title=How to make the Semantic Web more semantic\n | first=Peter\n | last=G\u00e4rdenfors\n | pages=17\u201334\n | publisher=IOS Press\n | year=2004\n | work=Formal Ontology in Information Systems: proceedings of the third international conference (FOIS-2004)}}</ref><ref name="Honkela08">{{cite journal\n | title=Simulating processes of concept formation and communication\n | year=2008\n | first1=Timo\n | last1=Honkela\n | first2=Ville\n | last2=K\u00f6n\u00f6nen\n | first3=Tiina\n | last3=Lindh-Knuutila\n | first4=Mari-Sanna\n | last4=Paukkeri\n | journal=Journal of Economic Methodology| volume=15\n | issue=3\n | pages=245\u2013259\n | doi=10.1080/13501780802321350\n | s2cid=16994027\n }}</ref>\n\n Enthusiasm about the semantic web could be tempered by concerns regarding [[Internet censorship|censorship]] and [[privacy]]. For instance, [[Intelligent text analysis|text-analyzing]] techniques can now be easily bypassed by using other words, metaphors for instance, or by using images in place of words. An advanced implementation of the semantic web would make it much easier for governments to control the viewing and creation of online information, as this information would be much easier for an automated content-blocking machine to understand. In addition, the issue has also been raised that, with the use of [[FOAF (software)|FOAF]] files and geolocation [[meta-data]], there would be very little anonymity associated with the authorship of articles on things such as a personal blog. Some of these concerns were addressed in the "Policy Aware Web" project<ref>{{cite web|url=http://www.policyawareweb.org/ |title=Policy Aware Web Project |publisher=Policyawareweb.org |access-date=2013-06-14}}</ref> and is an active research and development topic.\n\n Another criticism of the semantic web is that it would be much more time-consuming to create and publish content because there would need to be two formats for one piece of data: one for human viewing and one for machines. However, many web applications in development are addressing this issue by creating a machine-readable format upon the publishing of data or the request of a machine for such data. The development of microformats has been one reaction to this kind of criticism. Another argument in defense of the feasibility of semantic web is the likely falling price of human intelligence tasks in digital labor markets, such as [[Amazon.com|Amazon]]'s [[Amazon Mechanical Turk|Mechanical Turk]].{{Citation needed|date=February 2015}}\n\nSpecifications such as [[eRDF (data format)|eRDF]] and RDFa allow arbitrary RDF data to be embedded in HTML pages. The [[GRDDL]] (Gleaning Resource Descriptions from Dialects of Language) mechanism allows existing material (including microformats) to be automatically interpreted as RDF, so publishers only need to use a single format, such as HTML.\n\n The first research group explicitly focusing on the Corporate Semantic Web was the ACACIA team at [[Institut national de recherche en informatique et en automatique|INRIA-Sophia-Antipolis]], founded in 2002. Results of their work include the [[RDF Schema|RDF(S)]] based Corese<ref>{{cite journal |last1=Corby |first1=Olivier |last2=Dieng-Kuntz |first2=Rose |last3=Zucker |first3=Catherine Faron |last4=Gandon |first4=Fabien |title=Searching the Semantic Web: Approximate Query Processing based on Ontologies |url=https://hal.inria.fr/hal-01150215 |journal=IEEE Intelligent Systems |year=2006 |pages=20\u201327 |language=en |doi=10.1109/MIS.2006.16 |volume=21 |s2cid=11488848 }}</ref> search engine, and the application of semantic web technology in the realm of [[distributed artificial intelligence]] for knowledge management (e.g. ontologies and [[multi-agent systems]] for corporate semantic Web) <ref>{{cite web |last1=Gandon |first1=Fabien |title=Distributed Artificial Intelligence And Knowledge Management: Ontologies And Multi-Agent Systems For A Corporate Semantic Web |url=https://tel.archives-ouvertes.fr/tel-00378201 |publisher=Universit\u00e9 Nice Sophia Antipolis |language=en |date=7 November 2002}}</ref> and [[E-learning]].<ref>{{cite conference\n | url=http://www-sop.inria.fr/acacia/personnel/Sylvain.Dehors/SW-EL@AIED-BuffaDehorsFaronSander_short.pdf\n | title=Towards a Corporate Semantic Web Approach in Designing Learning Systems: Review of the Trial Solutioins Project\n | first1=Michel | last1=Buffa\n | first2=Sylvain | last2=Dehors\n | first3=Catherine | last3=Faron-Zucker\n | first4=Peter | last4=Sander\n | book-title=International Workshop on Applications of Semantic Web Technologies for E-Learning\n | location=Amsterdam, Holland\n | pages=73\u201376\n | year=2005\n}}</ref>\n\nSince 2008, the Corporate Semantic Web research group, located at the [[Free University of Berlin]], focuses on building blocks: Corporate Semantic Search, Corporate Semantic Collaboration, and Corporate Ontology Engineering.<ref>{{cite web|url=http://www.corporate-semantic-web.de|title=Corporate Semantic Web - Home|website=Corporate-semantic-web.de|access-date=14 April 2018}}</ref>\n\nOntology engineering research includes the question of how to involve non-expert users in creating ontologies and semantically annotated content<ref>{{cite conference\n | url=http://iswc2012.semanticweb.org/sites/default/files/76490161.pdf\n | title=Semantic Enrichment by Non-Experts: Usability of Manual Annotation Tools\n | first1=Annika | last1=Hinze\n | first2=Ralf | last2=Heese\n | first3=Markus | last3=Luczak-R\u00f6sch\n | first4=Adrian | last4=Paschke\n | book-title=ISWC'12 - Proceedings of the 11th international conference on The Semantic Web\n | location=Boston, USA\n | pages=165\u2013181\n | year=2012\n}}</ref> and for extracting explicit knowledge from the interaction of users within enterprises.\n\n [[Tim O'Reilly]], who coined the term Web 2.0, proposed a long-term vision of the Semantic Web as a web of data, where sophisticated applications manipulate the data web.<ref>{{cite news|url=https://www.theguardian.com/technology/2006/apr/06/guardianweeklytechnologysection.timbernerslee |title=Spread the word, and join it up |first=S. A. |last=Mathieson |date=6 April 2006 |work=[[The Guardian]] |access-date=14 April 2018}}</ref> The data web transforms the World Wide Web from a [[Distributed computing|distributed]] [[file system]] into a distributed database system.<ref>{{cite web|url=https://novaspivack.typepad.com/nova_spivacks_weblog/2007/09/hyperdata.html |title=The Semantic Web, Collective Intelligence and Hyperdata |last=Spivack |first=Nova |date=18 September 2007 |website=novaspivack.typepad.com/nova_spivacks_weblog [This Blog has Moved to NovaSpivack.com] |access-date=14 April 2018}}</ref>\n\n {{Div col|colwidth=20em}}\n* [[AGRIS]]\n* [[Business semantics management]]\n* [[Computational semantics]]\n* [[Calais (Reuters product)]]\n* [[DBpedia]]\n* [[Entity\u2013attribute\u2013value model]]\n* [[EU Open Data Portal]]\n* [[Hyperdata]]\n* [[Internet of things]]\n* [[Linked data]]\n* [[List of emerging technologies]]\n* [[Nextbio]]\n* [[Ontology alignment]]\n* [[Ontology learning]]\n* [[Resource Description Framework|RDF]] and [[Web Ontology Language|OWL]]\n* [[Semantic computing]]\n* [[Semantic Geospatial Web]]\n* [[Semantic heterogeneity]]\n* [[Semantic integration]]\n* [[Semantic matching]]\n* [[Semantic MediaWiki]]\n* [[Semantic Sensor Web]]\n* [[Semantic social network]]\n* [[Semantic technology]]\n* ''[[Semantic Web (journal)|Semantic Web]]''\n* [[Semantically-Interlinked Online Communities]]\n* [[Smart-M3]]\n* [[Social Semantic Web]]\n* [[Web engineering]]\n* [[Web resource]]\n* [[Web science]]\n{{div col end}}\n\n {{Reflist\n|refs=\n<ref name="Berners-Lee">{{cite magazine |last1 = Berners-Lee |first1 = Tim |author2=James Hendler |author3=Ora Lassila |title=The Semantic Web |magazine=Scientific American |date=May 17, 2001 |url = https://www.scientificamerican.com/article/the-semantic-web/ |access-date=July 2, 2019 }}</ref>\n\n<ref name="W3C-SWA">{{cite web |url = http://www.w3.org/2001/sw/ |title = W3C Semantic Web Activity |date=November 7, 2011 |publisher=[[World Wide Web Consortium]] (W3C) |access-date=November 26, 2011 }}</ref>\n}}\n\n * {{cite book |title=A Developer's Guide to the Semantic Web,2nd ed. |author=Liyang Yu |publisher=Springer |date=December 14, 2014 |isbn=978-3-662-43796-4 |url=https://www.springer.com/computer/database+management+%26+information+retrieval/book/978-3-662-43795-7}}\n* [[commons:File:Aaron Swartz s A Programmable Web An Unfinished Work.pdf|Aaron Swartz's A Programmable Web: An unfinished Work]] donated by Morgan & Claypool Publishers after Aaron Swartz's death in January 2013.\n* {{cite book |title=A Semantic Web Primer, 2nd Edition |author=Grigoris Antoniou, [[Frank van Harmelen]] |publisher=The [[MIT Press]] |date=March 31, 2008 |isbn=978-0-262-01242-3}}\n* {{cite book |last1=Allemang |first1=Dean |last2=Hendler |first2=James |last3=Gandon |first3=Fabien |title=Semantic Web for the Working Ontologist : Effective Modeling for Linked Data, RDFS, and OWL |date=August 3, 2020 |publisher=ACM Books; 3rd edition |location=[New York, NY, USA] |isbn=978-1450376143 |edition=Third}}\n* {{cite book |title=Foundations of Semantic Web Technologies |author1=Pascal Hitzler |author2=Markus Kr\u00f6tzsch |author3=Sebastian Rudolph |publisher=CRCPress |date=August 25, 2009 |isbn=978-1-4200-9050-5 |url=http://www.semantic-web-book.org|author1-link=Pascal Hitzler }}\n* {{cite book |title=Explorer's Guide to the Semantic Web |author=Thomas B. Passin |publisher=Manning Publications |date=March 1, 2004 |isbn=978-1-932394-20-7}}\n* {{cite book |title=Semantic Web For Dummies |author=Jeffrey T. Pollock |publisher=For Dummies |date=March 23, 2009 |isbn=978-0-470-39679-7 |url=https://archive.org/details/isbn_9780470396797 |url-access=registration }}\n* {{cite journal |last1=Hitzler |first1=Pascal |title=A Review of the Semantic Web Field |journal=Communications of the ACM |date=February 2021 |volume=64 |issue=2 |pages=76\u201383 |doi=10.1145/3397512 |url=https://cacm.acm.org/magazines/2021/2/250085-a-review-of-the-semantic-web-field/fulltext|doi-access=free }}\n\n {{Sister project links|commons=Category:Semantic Web|d=Q54837|wikt=no|s=no|v=no|b=Semantic Web|n=no|q=no}}\n{{scholia|topic}}\n* {{Official website|http://www.w3.org/standards/semanticweb/}}\n* [http://www.intelligententerprise.com/showArticle.jhtml?articleID=184429656 Breakthrough Analysis: A Data Space for Information Coexistence]\n\n{{Semantic Web}}\n{{emerging technologies|topics=yes|infocom=yes}}\n{{Digital humanities}}\n{{Computable knowledge}}\n{{Authority control}}\n<!-- Please respect alphabetical order -->"}},
{"article_title": "Space elevator", "pageid": "29192", "revid": "1061578671", "timestamp": "2021-12-22T15:21:18Z", "history_paths": [["Space elevator --- Introduction ---", "History"]], "categories": ["space elevator", "exploratory engineering", "space colonization", "spacecraft propulsion", "spaceflight technology", "vertical transport devices", "space access", "hypothetical technology", "emerging technologies", "articles containing video clips"], "heading_tree": {"Space elevator --- Introduction ---": {"History": {"Early concepts": {}, "20th century": {}, "21st century": {}}, "In fiction": {}, "Physics": {"Apparent gravitational field": {}, "Cable section": {}, "Cable materials": {}}, "Structure": {"Base station": {}, "Cable": {}, "Climbers": {}, "Powering climbers": {}, "Counterweight": {}}, "Applications": {"Launching into deep space": {}, "Extraterrestrial elevators": {}}, "Construction": {"Safety issues and construction challenges": {}, "Economics": {}}, "International Space Elevator Consortium (ISEC)": {}, "Related concepts": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Space elevator --- Introduction ---|History": "[[File:\u041a\u043e\u043d\u0441\u0442\u0430\u043d\u0442\u0438\u043d \u0426\u0438\u043e\u043b\u043a\u043e\u0432\u0441\u043a\u0438\u0439.jpg|thumb|left|upright|[[Konstantin Tsiolkovsky]]]]\nThe key concept of the space elevator appeared in 1895 when [[Russia]]n scientist [[Konstantin Tsiolkovsky]] was inspired by the [[Eiffel Tower]] in [[Paris]]. He considered a similar tower that reached all the way into space and was built from the ground up to the altitude of 35,786 kilometers, the height of [[geostationary orbit]].<ref name="NASASci">{{cite web|url=https://science.nasa.gov/headlines/y2000/ast07sep_1.htm |title=The Audacious Space Elevator |publisher=NASA Science News |url-status=dead |access-date=September 27, 2008 |archive-url=https://web.archive.org/web/20080919070924/https://science.nasa.gov/headlines/y2000/ast07sep_1.htm |archive-date=September 19, 2008}}</ref> He noted that the top of such a tower would be circling [[Earth]] as in a geostationary orbit. Objects would acquire horizontal velocity due to the Earth's rotation as they rode up the tower, and an object released at the tower's top would have enough horizontal velocity to remain there in geostationary orbit. Tsiolkovsky's conceptual tower was a compression structure, while modern concepts call for a [[tensile structure]] (or "tether").\n\n Building a compression structure from the ground up proved an unrealistic task as there was no material in existence with enough compressive strength to support its own weight under such conditions.<ref name="JBIS1999">{{cite journal |author1=Landis, Geoffrey A. |author2=Cafarelli, Craig |name-list-style=amp |year = 1999 |title = The Tsiolkovski Tower Reexamined |journal = Journal of the British Interplanetary Society |volume = 52 |pages = 175\u2013180 |others = Presented as paper IAF-95-V.4.07, 46th International Astronautics Federation Congress, Oslo Norway, October 2\u20136, 1995 |bibcode = 1999JBIS...52..175L}}</ref> In 1959 the Russian engineer [[Yuri N. Artsutanov]] suggested a more feasible proposal. Artsutanov suggested using a geostationary [[satellite]] as the base from which to deploy the structure downward. By using a [[counterweight]], a cable would be lowered from geostationary orbit to the surface of Earth, while the counterweight was extended from the satellite away from Earth, keeping the cable constantly over the same spot on the surface of the Earth. Artsutanov's idea was introduced to the Russian-speaking public in an interview published in the Sunday supplement of ''[[Komsomolskaya Pravda]]'' in 1960,<ref>{{cite web |url=http://liftport.com/files/Artsutanov_Pravda_SE.pdf |archive-url=https://web.archive.org/web/20060506100948/http://liftport.com/files/Artsutanov_Pravda_SE.pdf |archive-date=May 6, 2006 |title=To the Cosmos by Electric Train |work=liftport.com |year=1960 |publisher=Young Person's Pravda |last=Artsutanov |first=Yu |access-date=March 5, 2006}}</ref> but was not available in English until much later. He also proposed tapering the cable thickness in order for the stress in the cable to remain constant. This gave a thinner cable at ground level that became thickest at the level of geostationary orbit.\n\nBoth the tower and cable ideas were proposed in [[David E. H. Jones]]' quasi-humorous ''Ariadne'' column in ''[[New Scientist]]'', December 24, 1964.\n\nIn 1966, Isaacs, Vine, Bradner and Bachus, four [[United States|American]] engineers, reinvented the concept, naming it a "Sky-Hook", and published their analysis in the journal [[Science (journal)|''Science'']].<ref>{{cite journal |title=Satellite Elongation into a True 'Sky-Hook' |year=1966 |journal= Science |volume = 151 |doi = 10.1126/science.151.3711.682 |author=Isaacs, J. D. |author2= A. C. Vine, H. Bradner and G. E. Bachus |bibcode = 1966Sci...151..682I |issue=3711 |pages=682\u20133 |last3=Bradner |last4=Bachus |pmid=17813792 |s2cid=32226322 }}</ref> They decided to determine what type of material would be required to build a space elevator, assuming it would be a straight cable with no variations in its cross section area, and found that the [[specific strength|strength]] required would be twice that of any then-existing material including [[graphite]], [[quartz]], and [[diamond]].\n\nIn 1975 an American scientist, [[Jerome Pearson]], reinvented the concept, publishing his analysis in the journal ''[[Acta Astronautica]]''. He designed<ref>{{cite journal |author = Pearson, J. |year = 1975 |title = The orbital tower: a spacecraft launcher using the Earth's rotational energy |url = http://www.star-tech-inc.com/papers/tower/tower.pdf |journal = Acta Astronautica |volume = 2 |pages = 785\u2013799 |doi = 10.1016/0094-5765(75)90021-1 |issue = 9\u201310 |bibcode = 1975AcAau...2..785P |citeseerx = 10.1.1.530.3120}}</ref> a cross-section-area altitude profile that tapered and would be better suited to building the elevator. The completed cable would be thickest at the geostationary orbit, where the tension was greatest, and would be narrowest at the tips to reduce the amount of weight per unit area of cross section that any point on the cable would have to bear. He suggested using a counterweight that would be slowly extended out to {{convert|144,000|km|mi|abbr=off|sp=us}} (almost half the distance to the [[Moon]]) as the lower sections of the elevator were built. Without a large counterweight, the upper portion of the cable would have to be longer than the lower due to the way [[Gravity|gravitational]] and centrifugal forces change with distance from Earth. His analysis included disturbances such as the gravitation of the Moon, wind and moving payloads up and down the cable. The weight of the material needed to build the elevator would have required thousands of [[Space Shuttle]] trips, although part of the material could be transported up the elevator when a minimum strength strand reached the ground or be manufactured in space from [[Asteroid mining|asteroidal]] or [[In-situ resource utilization|lunar ore]].\n\nAfter the development of [[carbon nanotubes]] in the 1990s, engineer David Smitherman of [[NASA]]/Marshall's Advanced Projects Office realized that the high strength of these materials might make the concept of a space elevator feasible, and put together a workshop at the [[Marshall Space Flight Center]], inviting many scientists and engineers to discuss concepts and compile plans for an elevator to turn the concept into a reality.\n\nIn 2000, another American scientist, [[Bradley C. Edwards]], suggested creating a {{convert|100,000|km|mi|abbr=on}} long paper-thin ribbon using a carbon nanotube composite material.<ref name="EDWARDS_PHASE_I_2000_472Edwards.html">Bradley C. Edwards, "[http://www.niac.usra.edu/studies/472Edwards.html The Space Elevator]"</ref> He chose the wide-thin ribbon-like cross-section shape rather than earlier circular cross-section concepts because that shape would stand a greater chance of surviving impacts by meteoroids. The ribbon cross-section shape also provided large surface area for climbers to climb with simple rollers. Supported by the [[NASA Institute for Advanced Concepts]], Edwards' work was expanded to cover the deployment scenario, climber design, power delivery system, [[Space debris|orbital debris]] avoidance, anchor system, surviving [[atomic oxygen]], avoiding lightning and hurricanes by locating the anchor in the western equatorial Pacific, construction costs, construction schedule, and environmental hazards.<ref name="Edwards" /><ref name="Smitherman">[http://www.nss.org/resources/library/spaceelevator/2000-SpaceElevator-NASA-CP210429.pdf "Space Elevators: An Advanced Earth-Space Infrastructure for the New Millennium"], NASA/CP-2000-210429, Marshall Space Flight Center, Huntsville, Alabama, 2000 ([https://web.archive.org/web/20150328040627/http://www.nss.org/resources/library/spaceelevator/2000-SpaceElevator-NASA-CP210429.pdf archived])</ref><ref>Science @ NASA, [https://science.nasa.gov/headlines/y2000/ast07sep_1.htm "Audacious & Outrageous: Space Elevators"] {{webarchive|url=https://web.archive.org/web/20080919070924/https://science.nasa.gov/headlines/y2000/ast07sep_1.htm |date=September 19, 2008}}, September 2000</ref>\n\n \nTo speed space elevator development, proponents have organized several [[Space Elevator Competitions|competitions]], similar to the [[Ansari X Prize]], for relevant technologies.<ref>{{cite web |url=http://www.nbcnews.com/id/5792719 |title=Space elevator contest proposed |first=Alan |last=Boyle |publisher=NBC News |date=August 27, 2004}}</ref><ref>{{cite web |url=http://www.elevator2010.org/ |title=The Space Elevator \u2013 Elevator:2010 |access-date=March 5, 2006}}</ref> Among them are [[Elevator:2010]], which organized annual competitions for climbers, ribbons and power-beaming systems from 2005 to 2009, the Robogames Space Elevator Ribbon Climbing competition,<ref>{{cite web |url=http://robogames.net/rules/climbing.php |title=Space Elevator Ribbon Climbing Robot Competition Rules |access-date=March 5, 2006 |archive-url = https://web.archive.org/web/20050206100051/http://robolympics.net/rules/climbing.shtml|archive-date=February 6, 2005}}</ref> as well as NASA's [[Centennial Challenges]] program, which, in March 2005, announced a partnership with the Spaceward Foundation (the operator of Elevator:2010), raising the total value of prizes to US$400,000.<ref>{{cite web |url=http://www.nasa.gov/home/hqnews/2005/mar/HQ_m05083_Centennial_prizes.html |title=NASA Announces First Centennial Challenges' Prizes |year=2005 |access-date=March 5, 2006}}</ref><ref>{{cite web |url=http://www.space.com/news/050323_centennial_challenge.html |title=NASA Details Cash Prizes for Space Privatization |first=Robert Roy |last=Britt |work=Space.com |date=March 24, 2005 |access-date=March 5, 2006}}</ref>\nThe first European Space Elevator Challenge (EuSEC) to establish a climber structure took place in August 2011.<ref>{{cite web |title=What's the European Space Elevator Challenge? |url=http://eusec.warr.de/?eusec|publisher=European Space Elevator Challenge |access-date=April 21, 2011}}</ref>\n\nIn 2005, "the [[LiftPort Group]] of space elevator companies announced that it will be building a carbon nanotube manufacturing plant in [[Millville, New Jersey]], to supply various glass, plastic and metal companies with these strong materials. Although LiftPort hopes to eventually use carbon nanotubes in the construction of a {{convert|100,000|km|mi|abbr=on}} space elevator, this move will allow it to make money in the short term and conduct research and development into new production methods."<ref name="universetoday">{{cite news |url=http://www.universetoday.com/am/publish/liftport_manufacture_nanotubes.html?2742005 |title=Space Elevator Group to Manufacture Nanotubes |date=April 27, 2005 |first=Fraser |last=Cain |work=Universe Today |access-date=March 5, 2006}}</ref> Their announced goal was a space elevator launch in 2010. On February 13, 2006 the LiftPort Group announced that, earlier the same month, they had tested a mile of "space-elevator tether" made of carbon-fiber composite strings and fiberglass tape measuring {{convert|5|cm|in|abbr=on}} wide and 1 mm (approx. 13 sheets of paper) thick, lifted with balloons.<ref>{{cite news |url=http://www.newscientistspace.com/article/dn8725.html |title=Space-elevator tether climbs a mile high |date=February 15, 2006 |work=New Scientist |first=Kimm |last=Groshong |access-date=March 5, 2006}}</ref> In April 2019, Liftport CEO Michael Laine admitted little progress has been made on the company's lofty space elevator ambitions, even after receiving more than $200,000 in seed funding. The carbon nanotube manufacturing facility that Liftport announced in 2005 was never built.<ref>{{cite web |title=If a space elevator was ever going to happen, it could have gotten its start in N.J. Here's how it went wrong |url=https://www.nj.com/cumberland/2019/04/if-a-space-elevator-was-ever-going-to-happen-it-could-have-gotten-its-start-in-nj-heres-how-it-went-wrong.html |publisher=NJ.com |date=March 28, 2019 |access-date=May 11, 2019}}</ref>\n\nIn 2006 the book "Leaving the Planet by Space Elevator" was published by Dr Brad Edwards and Philip Ragan, containing a comprehensive review of the history, construction challenges and implementation plans for future space elevators, including space elevators on the Moon and Mars.\n\nIn 2007, [[Elevator:2010]] held the 2007 Space Elevator games, which featured US$500,000 awards for each of the two competitions, ($1,000,000 total) as well as an additional $4,000,000 to be awarded over the next five years for space elevator related technologies.<ref>[https://web.archive.org/web/20100118153108/http://www.spaceward.org/elevator2010 Elevator:2010 \u2013 The Space Elevator Challenge]. spaceward.org</ref> No teams won the competition, but a team from [[MIT]] entered the first 2-gram (0.07 oz), 100-percent carbon nanotube entry into the competition.<ref>[https://web.archive.org/web/20071101081423/http://www.spaceward.org/games07Wrapup.html Spaceward Games 2007]. The Spaceward Foundation</ref>  Japan held an international conference in November 2008 to draw up a timetable for building the elevator.<ref name="JapanUKTimes">{{cite news | title = Japan hopes to turn sci-fi into reality with elevator to the stars | url=http://www.thetimes.co.uk/tto/news/world/article1967078.ece | work=The Times | location=London | first=Leo | last=Lewis | date=September 22, 2008 | access-date=May 23, 2010}} Lewis, Leo; News International Group; accessed September 22, 2008.</ref>\n\nIn 2008 the book ''Leaving the Planet by Space Elevator'' was published in Japanese and entered the Japanese best-seller list.<ref>{{cite web | title = Leaving the Planet by Space Elevator | url = http://www.leavingtheplanet.com/}} Edwards, Bradley C. and Westling, Eric A. and Ragan, Philip; Leasown Pty Ltd.; accessed September 26, 2008.</ref><ref>{{Cite book|title=Space Elevator: Leaving the Planet by Space Elevator|date=2008|isbn=9784270003350|location=\u6771\u4eac|language=ja|last1=Edwards|first1=Bradley C|last2=Philip Ragan}}</ref> This led to Shuichi Ono, chairman of the Japan Space Elevator Association, unveiling a space-elevator plan, putting forth what observers considered an extremely low cost estimate of a trillion yen (\u00a35 billion / $8 billion) to build one.<ref name="JapanUKTimes" />\n\nIn 2012, the [[Obayashi Corporation]] announced that it could build a space elevator by 2050 using carbon nanotube technology.<ref name="physorg_obayashi">{{cite news| url=http://www.physorg.com/news/2012-02-japan-builder-eyes-space-elevator.html | website=Phys.org | title=Going up: Japan builder eyes space elevator | date=February 22, 2012}}</ref> The design's passenger climber would be able to reach the GEO level after an 8 day trip.<ref>{{cite news| url=https://www.smithsonianmag.com/smart-news/researchers-take-tiny-first-step-toward-space-elevator-180970212/ | title=Japan Takes Tiny First Step Toward Space Elevator | date=September 5, 2018 |work=Smithsonian Magazine |first=Jason |last=Daley}}</ref> Further details have been published in 2016.<ref>{{cite journal |last1=Ishikawa |first1=Y. |date=2016 |title=Obayashi Corporation's Space Elevator Construction Concept |url=https://ui.adsabs.harvard.edu/abs/2016JBIS...69..227I/abstract |journal=Journal of the British Interplanetary Society |volume=69 |issue= |pages=227\u2013239 |doi= |bibcode=2016JBIS...69..227I |access-date=January 5, 2021}}</ref>\n\nIn 2013, the [[International Academy of Astronautics]] published a technological feasibility assessment which concluded that the critical capability improvement needed was the tether material, which was projected to achieve the necessary [[specific strength]] within 20 years. The four-year long study looked into many facets of space elevator development including missions, development schedules, financial investments, revenue flow, and benefits. It was reported that it would be possible to operationally survive smaller impacts and avoid larger impacts, with meteors and space debris, and that the estimated cost of lifting a kilogram of payload to GEO and beyond would be $500.<ref>{{Cite book|title = Space Elevators: An Assessment of the Technological Feasibility and the Way Forward|last1 = Swan|last2 =Raitt|last3 =Swan|last4 = Penny|last5 =Knapman|first1 = Peter A.|first2 = David I.|first3 = Cathy W.|first4 = Robert E.|first5 = John M.|publisher = International Academy of Astronautics|year = 2013|isbn = 9782917761311|location = Virginia, US|pages = 10\u201311, 207\u2013208}}</ref><ref>Swan, P., Penny, R., Swan, C. "Space Elevator Survivability, Space Debris Mitigation", Lulu.com Publishers, 2011{{self-published source|date=February 2020}}</ref>{{self-published inline|date=February 2020}}\n\nIn 2014, Google X's Rapid Evaluation R&D team began the design of a Space Elevator, eventually finding that no one had yet manufactured a perfectly formed [[carbon nanotube]] strand longer than a meter. They thus decided to put the project in "deep freeze" and also keep tabs on any advances in the carbon nanotube field.<ref>{{cite web|last=Gayomali|first=Chris|title=Google X Confirms The Rumors: It Really Did Try To Design A Space Elevator|url=http://www.fastcompany.com/3029138/world-changing-ideas/google-x-confirms-the-rumors-it-really-did-try-to-design-a-space-elevat?partner=rss|work=Fast Company |date=April 15, 2014 |access-date=April 17, 2014}}</ref>\n\nIn 2018, researchers at Japan's [[Shizuoka University]] launched STARS-Me, two [[CubeSat]]s connected by a tether, which a mini-elevator will travel on.<ref>{{Cite web | url=https://www.nbcnews.com/mach/science/colossal-elevator-space-could-be-going-sooner-you-ever-imagined-ncna915421 | title=A colossal elevator to space could be going up sooner than you ever imagined |work=NBC News |date=October 2, 2018 |first=Scott |last=Snowden}}</ref><ref>{{cite web |url=https://www.curbed.com/2018/9/12/17851500/space-elevator-japan-news |title=Japan is trying to build an elevator to space |publisher=Curbed.com |first=Meghan |last=Barber |date=September 12, 2018 |access-date=September 18, 2018}}</ref> The experiment was launched as a test bed for a larger structure.<ref>{{Cite web | url=https://gizmodo.com/japan-testing-miniature-space-elevator-near-the-interna-1828800558 |title = Japan Testing Miniature Space Elevator Near the International Space Station}}</ref>\n\nIn 2019, the [[International Academy of Astronautics]] published "Road to the Space Elevator Era",<ref>{{cite book |authors=Swan P A, Raitt D I, Knapman J M, Tsuchida A, Fitzgerald M A, Ishikawa Y |title=Road to the Space Elevator Era" |date=May 30, 2019 |publisher=International Academy of Astronautics |isbn=978-0-9913370-3-3 |url=https://www.heinleinbooks.com/product-page/road-to-the-space-elevator-era}}</ref> a study report summarizing the assessment of the space elevator as of summer 2018.  The essence is that a broad group of space professionals gathered and assessed the status of the space elevator development, each contributing their expertise and coming to similar conclusions : (a) Earth Space Elevators seem feasible, reinforcing the IAA 2013 study conclusion (b) Space Elevator development initiation is nearer than most think.  This last conclusion is based on a potential process for manufacturing macro-scale single crystal [[graphene]]<ref>{{Cite web|url=https://www.azom.com/article.aspx?ArticleID=16371|title=Space Elevator Technology and Graphene: An Interview with Adrian Nixon|date=July 23, 2018}}</ref> with higher [[specific strength]] than [[carbon nanotube]]s."}},
{"article_title": "Signal processing", "pageid": "29324", "revid": "1062720685", "timestamp": "2021-12-30T03:34:30Z", "history_paths": [["Signal processing --- Introduction ---", "History"]], "categories": ["signal processing", "mass media technology", "telecommunication theory"], "heading_tree": {"Signal processing --- Introduction ---": {"History": {}, "Categories": {"Analog": {}, "Continuous time": {}, "Discrete time": {}, "Digital": {}, "Nonlinear": {}, "Statistical": {}}, "Application fields": {}, "Typical devices": {}, "Mathematical methods applied": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Signal processing --- Introduction ---|History": "According to [[Alan V. Oppenheim]] and [[Ronald W. Schafer]], the principles of signal processing can be found in the classical [[numerical analysis]] techniques of the 17th century.  They further state that the digital refinement of these techniques can be found in the digital [[control system]]s of the 1940s and 1950s.<ref>{{cite book |title=Digital Signal Processing |year=1975 |publisher=[[Prentice Hall]] |isbn=0-13-214635-5 |author=Oppenheim, Alan V. |author2=Schafer, Ronald W. |page= 5}}</ref>\n\nIn 1948, [[Claude Shannon]] wrote the influential paper "[[A Mathematical Theory of Communication]]" which was published in the [[Bell System Technical Journal]].<ref>{{cite web |url=https://www.computerhistory.org/revolution/digital-logic/12/269/1331 |title=A Mathematical Theory of Communication \u2013 CHM Revolution |website=Computer History |access-date=2019-05-13}}</ref>  The paper laid the groundwork for later development of information communication systems and the processing of signals for transmission.<ref name=fifty>{{cite book |title=Fifty Years of Signal Processing: The IEEE Signal Processing Society and its Technologies, 1948\u20131998 |publisher=The IEEE Signal Processing Society |year=1998}}</ref>\n\nSignal processing matured and flourished in the 1960s and 1970s, and digital signal processing became widely used with specialized [[digital signal processor]] chips in the 1980s.<ref name=fifty/>"}},
{"article_title": "Solar sail", "pageid": "29420", "revid": "1062967845", "timestamp": "2021-12-31T13:15:12Z", "history_paths": [["Solar sail --- Introduction ---", "History of concept"]], "categories": ["solar sailing", "spacecraft attitude control", "spacecraft propulsion", "spacecraft components", "interstellar travel", "microwave technology", "photonics", "emerging technologies", "japanese inventions"], "heading_tree": {"Solar sail --- Introduction ---": {"History of concept": {}, "Physical principles": {"Solar radiation pressure": {}, "Sail parameters": {}, "Attitude control": {}, "Constraints": {}}, "Applications": {"Inner planets": {}, "Outer planets": {}, "Oort Cloud/Sun's inner gravity focus": {}, "Satellites": {}, "Trajectory corrections": {}, "Interstellar flight": {}, "Deorbiting artificial satellites": {}}, "Sail configurations": {}, "Electric solar wind sail": {}, "Magnetic sail": {}, "Sail making": {"Materials": {}, "Reflection and emissivity layers": {}, "Fabrication": {}}, "Operations": {"Changing orbits": {}, "Swing-by maneuvers": {"Interstellar travel catalog to use photogravitational assists for a full stop.": {}}}, "Projects operating or completed": {"Attitude (orientation) control": {}, "Ground deployment tests": {}, "Suborbital tests": {}, "IKAROS 2010": {}, "NanoSail-D 2010": {}, "Planetary Society LightSail Projects": {}}, "Projects in development or proposed": {"Sunjammer 2015": {}, "Gossamer deorbit sail": {}, "NEA Scout": {}, "OKEANOS": {}, "Breakthrough Starshot": {}, "''Solar Cruiser''": {}}, "In popular culture": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Solar sail --- Introduction ---|History of concept": "[[Johannes Kepler]] observed that [[comet]] tails point away from the Sun and suggested that the Sun caused the effect. In a letter to Galileo in 1610, he wrote, "Provide ships or sails adapted to the heavenly breezes, and there will be some who will brave even that void." He might have had the comet tail phenomenon in mind when he wrote those words, although his publications on comet tails came several years later.<ref>Johannes Kepler (1604) ''Ad vitellionem parali pomena'', Frankfort; (1619) ''De cometis liballi tres '', Augsburg</ref>\n\n[[James Clerk Maxwell]], in 1861\u20131864, published his theory of [[electromagnetic field]]s and radiation, which shows that light has [[momentum]] and thus can exert pressure on objects. [[Maxwell's equations]] provide the theoretical foundation for sailing with light pressure. So by 1864, the physics community and beyond knew [[sunlight]] carried momentum that would exert a pressure on objects.\n\n[[Jules Verne]], in ''From the Earth to the Moon'',<ref name="Verne1865">Jules Verne (1865) ''De la Terre \u00e0 la Lune'' (''From the Earth to the Moon'')</ref> published in 1865, wrote "there will some day appear velocities far greater than these [of the planets and the projectile], of which light or electricity will probably be the mechanical agent ... we shall one day travel to the moon, the planets, and the stars."<ref name="Impey">Chris Impey, ''Beyond: Our Future in Space,'' W. W. Norton & Company (2015)</ref> This is possibly the first published recognition that light could move ships through space.\n\n[[Pyotr Lebedev]] was first to successfully demonstrate light pressure, which he did in 1899 with a torsional balance;<ref>P. Lebedev, 1901, "Untersuchungen \u00fcber die Druckkr\u00e4fte des Lichtes", ''Annalen der Physik'', 1901</ref> Ernest Nichols and Gordon Hull conducted a similar independent experiment in 1901 using a [[Nichols radiometer]].<ref>{{cite web|url=http://dujs.dartmouth.edu/spring-2008-10th-anniversary-edition/what-else-has-happened-a-celebration-of-the-legacy-of-physics-at-dartmouth|title=A Celebration of the Legacy of Physics at Dartmouth |last=Lee|first=Dillon |year=2008|work=Dartmouth Undergraduate Journal of Science|publisher=Dartmouth College|access-date=2009-06-11}}</ref>\n\n[[Svante Arrhenius]] predicted in 1908 the possibility of solar radiation pressure distributing life spores across interstellar distances, providing one means to explain the concept of [[panspermia]]. He apparently was the first scientist to state that light could move objects between stars.<ref>Svante Arrhenius (1908) ''Worlds in the Making''</ref>\n\n[[Konstantin Tsiolkovsky]] first proposed using the pressure of sunlight to propel spacecraft through space and suggested, "using tremendous mirrors of very thin sheets to utilize the pressure of sunlight to attain cosmic velocities".<ref>Urbanczyk, Mgr., "Solar Sails-A Realistic Propulsion for Space Craft", Translation Branch Redstone Scientific Information Center Research and Development Directorate U.S. Army Missile Command Redstone Arsenal, Alabama, 1965.</ref>\n\n[[Friedrich Zander]] (Tsander) published a technical paper in 1925 that included technical analysis of solar sailing. Zander wrote of "applying small forces" using "light pressure or transmission of light energy to distances by means of very thin mirrors".<ref>Friedrich Zander's 1925 paper, "Problems of flight by jet propulsion: interplanetary flights", was translated by NASA. See NASA Technical Translation F-147 (1964), p. 230.</ref>\n\n[[JBS Haldane]] speculated in 1927 about the invention of tubular spaceships that would take humanity to space and how "wings of metallic foil of a square kilometre or more in area are spread out to catch the Sun's radiation pressure".<ref>JBS Haldane, ''The Last Judgement'', New York and London, Harper & Brothers, 1927.</ref>\n\n[[J. D. Bernal]] wrote in 1929, "A form of space sailing might be developed which used the repulsive effect of the Sun's rays instead of wind. A space vessel spreading its large, metallic wings, acres in extent, to the full, might be blown to the limit of Neptune's orbit. Then, to increase its speed, it would tack, close-hauled, down the gravitational field, spreading full sail again as it rushed past the Sun."<ref>J. D. Bernal (1929) ''The World, the Flesh & the Devil: An Enquiry into the Future of the Three Enemies of the Rational Soul''</ref>\n\n[[Carl Sagan]], in the 1970s, popularized the idea of sailing on light using a giant structure which would reflect [[photons]] in one direction, creating momentum. He brought up his ideas in college lectures, books, and television shows. He was fixated on quickly launching this spacecraft in time to perform a rendezvous with [[Halley's Comet]]. Unfortunately, the mission didn't take place in time and he would never live to finally see it through.{{Citation needed|date=September 2020}}\n\nThe first formal technology and design effort for a solar sail began in 1976 at [[Jet Propulsion Laboratory]] for a proposed mission to rendezvous with [[Halley's Comet]].<ref name="Wright " />"}},
{"article_title": "Simula", "pageid": "29513", "revid": "1054685873", "timestamp": "2021-11-11T14:54:36Z", "history_paths": [["Simula --- Introduction ---", "History"]], "categories": ["algol 60 dialect", "class-based programming languages", "norwegian inventions", "programming languages created in 1962", "science and technology in norway", "simulation programming languages", "programming languages"], "heading_tree": {"Simula --- Introduction ---": {"History": {}, "Sample code": {"Minimal program": {}, "Classic Hello world": {}, "Classes, subclasses and virtual procedures": {}, "Call by name": {}, "Simulation": {}}, "See also": {}, "Notes": {}, "Sources": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Simula --- Introduction ---|History": "The following account is based on Jan Rune Holmevik's historical essay.<ref>\n{{Cite journal\n  | last = Holmevik\n  | first = Jan Rune\n  | title = Compiling Simula: A historical study of technological genesis\n  | journal = IEEE Annals of the History of Computing\n  | volume = 16\n  | issue = 4\n  | pages = 25\u201337\n  | year = 1994\n  | url = http://www.idi.ntnu.no/grupper/su/publ/simula/holmevik-simula-ieeeannals94.pdf\n  | doi = 10.1109/85.329756\n  | s2cid = 18148999\n | access-date = 12 May 2010}}\n</ref><ref>{{cite web |last=Holmevik |first=Jan Rune |url=http://heim.ifi.uio.no/~cim/sim_history.html |title=Compiling Simula |publisher=Institute for Studies in Research and Higher Education |location=Oslo, Norway |url-status=dead |archive-url=https://web.archive.org/web/20090420140846/http://heim.ifi.uio.no/~cim/sim_history.html |archive-date=20 April 2009 |access-date=19 April 2017}}</ref>\n\n[[Kristen Nygaard]] started writing computer simulation programs in 1957. Nygaard saw a need for a better way to describe the heterogeneity and the [[Instruction (computer science)|operation]] of a system. To go further with his ideas on a [[Formal language|formal]] [[computer language]] for describing a system, Nygaard realized that he needed someone with more [[computer programming]] skills than he had. [[Ole-Johan Dahl]] joined him on his work January 1962. The decision of linking the language up to [[ALGOL 60]] was made shortly after. By May 1962, the main concepts for a [[simulation]] [[programming language|language]] were set. ''SIMULA I'' was born, a special purpose programming language for simulating discrete event systems.\n\nKristen Nygaard was invited to visit the [[Eckert\u2013Mauchly Computer Corporation]] late May 1962 in connection with the marketing of their new [[UNIVAC 1107]] computer. At that visit, Nygaard presented the ideas of Simula to [[Bob Bemer|Robert Bemer]], the director of systems programming at [[Univac]]. Bemer was a great [[ALGOL]] fan and found the Simula project compelling. Bemer was also [[chairperson]] of a session at the second international conference on information processing hosted by [[International Federation for Information Processing]] (IFIP). He invited Nygaard, who presented the paper "SIMULA \u2013 An Extension of ALGOL to the Description of Discrete-Event Networks".\n\nThe [[Norwegian Computing Center]] got a [[UNIVAC 1107]] in August 1963 at a considerable discount, on which Dahl implemented the SIMULA I under contract with UNIVAC. The implementation was based on the UNIVAC [[ALGOL 60]] compiler. SIMULA I was fully operational on the UNIVAC 1107 by January 1965. In the following few years, Dahl and Nygaard spent a lot of time teaching Simula. Simula spread to several countries around the world and SIMULA I was later implemented on other computers including the [[Burroughs large systems|Burroughs B5500]] and the Russian [[Ural (computer)|Ural-16]].\n\nIn 1966 [[C. A. R. Hoare]] introduced the concept of record class construct, which Dahl and Nygaard extended with the concept of prefixing and other features to meet their requirements for a generalized process concept. Dahl and Nygaard presented their paper on [[Class (computer programming)|Class]] and [[Subclass (computer science)|Subclass]] declarations at the IFIP Working Conference on [[simulation language]]s in [[Oslo]], May 1967. This paper became the first formal definition of Simula 67. In June 1967, a conference was held to standardize the language and initiate a number of implementations. Dahl proposed to unify the [[data type|type]] and the class concept. This led to serious discussions, and the proposal was rejected by the board. Simula 67 was formally standardized on the first meeting of the Simula Standards Group (SSG) in February 1968.\n\nSimula was influential in the development of [[Smalltalk]] and later [[object-oriented programming]] languages. It also helped inspire the [[actor model]] of concurrent computation although Simula only supports [[coroutine]]s and not true [[Concurrency (computer science)|concurrency]].<ref>{{Cite book |last=Lehrmann Madsen |first=Ole |chapter=Building Safe Concurrency Abstractions |title=Concurrent Objects and Beyond |series=Lecture Notes in Computer Science |publisher=Springer |year=2014 |volume=8665 |editor-last=Agha |editor-first=Gul |editor2-last=Igarashi |editor2-first=Atsushi |editor3-last=Kobayashi |editor3-first=Naoki |editor4-last=Masuhara |editor4-first=Hidehiko |editor5-last=Matsuoka |editor5-first=Satoshi |editor6-last=Shibayama |editor6-first=Etsuya |editor7-last=Taura |editor7-first=Kenjiro |location=Berlin |pages=68 |isbn=978-3-662-44471-9 |doi=10.1007/978-3-662-44471-9|s2cid=1000741 }}</ref>\n\nIn the late sixties and the early seventies, there were four main implementations of Simula:\n\n* [[UNIVAC]] 1100 by [[Norwegian Computing Center]] (NCC)\n* [[System/360]] and [[System/370]] by NCC\n* [[CDC 3000]] by [[University of Oslo]]'s Joint Computer Installation at Kjeller\n* [[TOPS-10]] by [[Swedish National Defence Research Institute]] (FOA)\n\nThese implementations were ported to a wide range of platforms. The [[TOPS-10]] implemented the concept of public, protected, and private member variables and procedures, that later was integrated into Simula 87. Simula 87 is the latest standard and is ported to a wide range of platforms. There are mainly four implementations:\n\n* Simula AS\n* Lund Simula\n* GNU Cim<ref>{{cite web |url=https://www.gnu.org/software/cim/ |title=GNU Cim}}</ref>\n* Portable Simula Revisited<ref>{{cite web |title=Portable Simula Revisited |url=https://portablesimula.github.io/github.io/ |website=GitHub |access-date=17 June 2019}}</ref>\n\nIn November 2001, Dahl and Nygaard were awarded the [[IEEE John von Neumann Medal]] by the [[Institute of Electrical and Electronics Engineers]] "For the introduction of the concepts underlying object-oriented programming through the design and implementation of SIMULA 67". In April 2002, they received the 2001 A. M. [[Turing Award]] by the [[Association for Computing Machinery]] (ACM), with the citation: "For ideas fundamental to the emergence of object oriented programming, through their design of the programming languages Simula I and Simula 67." Dahl and Nygaard died in June and August of that year, respectively, <ref>{{cite web |url=http://www.acm.org/announcements/turing_obit.html |title=ACM Ole-Johan Dahl and Kristen Nygaard - Obituary |publisher=Acm.org |access-date=14 January 2012 |url-status=dead |archive-url=https://web.archive.org/web/20110719085543/http://www.acm.org/announcements/turing_obit.html |archive-date=19 July 2011}}</ref> before the ACM Turing Award Lecture<ref>{{cite web|url=http://www.informatik.uni-trier.de/~ley/db/journals/cacm/turing.html |title=ACM Turing Award Lectures |publisher=Informatik.uni-trier.de |access-date=14 January 2012}}</ref> that was scheduled to be delivered at the November 2002 [[OOPSLA]] conference in Seattle.\n\n[[Simula Research Laboratory]] is a [[research institute]] named after the Simula language, and Nygaard held a part-time position there from the opening in 2001. The new Computer Science building at the [[University of Oslo]] is named Ole Johan Dahl's House, in Dahl's honour, and the main auditorium is named Simula."}},
{"article_title": "Sierpi\u0144ski triangle", "pageid": "29638", "revid": "1056092956", "timestamp": "2021-11-19T18:02:08Z", "history_paths": [["Sierpi\u0144ski triangle --- Introduction ---", "History"]], "categories": ["factorial and binomial topics", "curves", "topological spaces", "types of triangles", "cellular automaton patterns", "science and technology in poland", "l-systems"], "heading_tree": {"Sierpi\u0144ski triangle --- Introduction ---": {"Constructions": {"Removing triangles": {}, "Shrinking and duplication": {}, "Chaos game": {}, "Arrowhead construction of Sierpinski gasket": {}, "Cellular automata": {}, "Pascal's triangle": {}, "Towers of Hanoi": {}}, "Properties": {}, "Generalization to other moduli": {}, "Analogues in higher dimensions": {}, "History": {}, "Etymology": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Sierpi\u0144ski triangle --- Introduction ---|History": "[[Wac\u0142aw Sierpi\u0144ski]] described the Sierpinski triangle in 1915. However, similar patterns appear already as a common motif of 13th-century [[Cosmatesque]] inlay stonework.<ref>{{cite journal | last = Williams | first = Kim | author-link = Kim Williams (architect) | editor-last = Stewart | editor-first = Ian | editor-link = Ian Stewart (mathematician) | date = December 1997 | department = The Mathematical Tourist | doi = 10.1007/bf03024339 | issue = 1 | journal = [[The Mathematical Intelligencer]] | pages = 41\u201345 | title = The pavements of the Cosmati | volume = 19}}</ref>\n\nThe [[Apollonian gasket]] was first described by [[Apollonius of Perga]] (3rd century BC) and further analyzed by [[Gottfried Leibniz]] (17th century), and is a curved precursor of the 20th-century Sierpi\u0144ski triangle.<ref>{{cite book| author = Mandelbrot B| year = 1983| title = The Fractal Geometry of Nature| publisher = W. H. Freeman| location = New York| isbn = 978-0-7167-1186-5| page = [https://archive.org/details/fractalgeometryo00beno/page/170 170]| url-access = registration| url = https://archive.org/details/fractalgeometryo00beno/page/170| author-link = Benoit Mandelbrot}}<br>{{cite book| author = Aste T, [[Denis Weaire|Weaire D]]| year = 2008| title = The Pursuit of Perfect Packing |title-link= The Pursuit of Perfect Packing | edition = 2nd| publisher = Taylor and Francis| location = New York| isbn = 978-1-4200-6817-7| pages = 131\u2013138}}</ref>"}},
{"article_title": "Technology", "pageid": "29816", "revid": "1062668178", "timestamp": "2021-12-29T20:50:44Z", "history_paths": [["Technology --- Introduction ---", "History"]], "categories": ["technology", "technology systems", "main topic articles"], "heading_tree": {"Technology --- Introduction ---": {"Definition and usage": {}, "Science, engineering, and technology": {}, "History": {"Paleolithic (2.5 Ma \u2013 10 ka)": {"Stone tools": {}, "Fire": {}, "Clothing and shelter": {}}, "Neolithic through classical antiquity (10 ka \u2013 300 CE)": {"Metal tools": {}, "Energy and transport": {}, "Plumbing": {}}, "Medieval and modern history (300 CE \u2013 present)": {}}, "Philosophy": {"Technicism": {}, "Optimism": {}, "Skepticism and critics": {}, "Appropriate technology": {}, "Optimism and skepticism in the 21st century": {}, "Complex technological systems": {}}, "Other animal species": {}, "Future technology": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Technology --- Introduction ---|History": "{{Main|History of technology|Timeline of electrical and electronic engineering|Timeline of historic inventions}}\n\n [[File:Chopper of Dmanisi.png|thumb|right|A primitive [[chopper (archaeology)|chopper]]]]\n{{further|Outline of prehistoric technology}}\n\nThe use of tools by [[Homo (genus)|early humans]] was partly a process of discovery and of evolution. Early humans evolved from a [[Australopithecus afarensis|species]] of [[foraging]] [[hominids]] which were already [[bipedal]],<ref>{{cite web|access-date=17 May 2008|url=http://www.bbc.co.uk/sn/prehistoric_life/human/human_evolution/mother_of_man1.shtml|title=Mother of man \u2013 3.2 million years ago|publisher=BBC|archive-url=https://web.archive.org/web/20071012164551/http://www.bbc.co.uk/sn/prehistoric_life/human/human_evolution/mother_of_man1.shtml|archive-date=12 October 2007|url-status=live|df=dmy-all}}</ref> with a brain mass approximately one third of modern humans.<ref>{{cite web|url=http://www.history.com/encyclopedia.do?articleId=212317|title=Human Evolution|publisher=[[History (U.S. TV channel)|History Channel]]|access-date=17 May 2008|archive-url=https://web.archive.org/web/20080423204038/http://www.history.com/encyclopedia.do?articleId=212317|archive-date=23 April 2008}}</ref> Tool use remained relatively unchanged for most of early human history. Approximately 50,000 years ago, the use of tools and a [[behavioral modernity|complex set of behaviors]] emerged, believed by many archaeologists to be connected to the emergence of fully modern [[language]].<ref>{{Cite news|url=https://www.nytimes.com/2003/07/15/science/early-voices-the-leap-to-language.html|title=Early Voices: The Leap to Language|last=Wade|first=Nicholas|date=15 July 2003|work=The New York Times|access-date=7 November 2016|archive-url=https://web.archive.org/web/20170312091336/http://www.nytimes.com/2003/07/15/science/early-voices-the-leap-to-language.html|archive-date=12 March 2017|url-status=live|df=dmy-all}}</ref>\n\n [[File:Biface de St Acheul MHNT.jpg|thumb|upright|Hand axes from the [[Acheulian]] period]]\n[[File:Fire in a fire pit.jpg|thumb|A campfire, often used to cook food]]\n[[File:Clovis Point.jpg|upright|thumb|A [[Clovis point]], made via [[pressure flaking]]]]\n[[File:Minoan Labrys Double Axe Arkalochori Cave Crete 1700-1600 BCE AM Herakleion.jpg|thumb|A metal axe, estimated creation from 1600-1700 [[pressure flaking]]]]\n\nHominids started using primitive stone tools millions of years ago. The earliest stone tools were little more than a fractured rock, but approximately 75,000 years ago,<ref>{{Cite news|url=https://www.wired.com/2010/10/stone-tool-sharpening/|title=Stone Agers Sharpened Skills 55,000 Years Earlier Than Thought|last=Bower|first=Bruce|date=29 October 2010|work=WIRED|access-date=7 November 2016|archive-url=https://web.archive.org/web/20161108133359/https://www.wired.com/2010/10/stone-tool-sharpening/|archive-date=8 November 2016|url-status=live|df=dmy-all}}</ref> [[pressure flaking]] provided a way to make much finer work.\n\n {{main|Control of fire by early humans}}\nThe discovery and use of [[fire]], a simple [[energy]] source with many profound uses, was a turning point in the technological evolution of humankind.<ref>{{cite book | last=Crump | first=Thomas | title=A Brief History of Science | year=2001 | publisher=[[Constable & Robinson]] | isbn=978-1-84119-235-2 | page=9}}</ref> The exact date of its discovery is not known; evidence of burnt animal bones at the [[Cradle of Humankind]] suggests that the domestication of fire occurred before 1 Ma;<ref>{{cite web | url=https://whc.unesco.org/pg.cfm?cid=31&id_site=915 | title=Fossil Hominid Sites of Sterkfontein, Swartkrans, Kromdraai, and Environs | access-date=10 March 2007 | publisher=[[UNESCO]] | archive-url=https://web.archive.org/web/20070327133817/https://whc.unesco.org/pg.cfm?cid=31&id_site=915 | archive-date=27 March 2007 | url-status=live | df=dmy-all }}</ref> scholarly consensus indicates that ''[[Homo erectus]]'' had controlled fire by between 500 and 400 ka.<ref>{{cite web|url=http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab10|title=Stone Age Man|publisher=History World|access-date=13 February 2007|archive-url=https://web.archive.org/web/20070310211601/http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab10|archive-date=10 March 2007|url-status=live|df=dmy-all}}</ref><ref>{{cite journal | title=Hominid Use of Fire in the Lower and Middle Pleistocene | last=James | first=Steven R. | journal=[[Current Anthropology]] | volume=30 | issue=1 | pages=1\u201326 |date=February 1989 | doi=10.1086/203705 | jstor=2743299| s2cid=146473957 }}</ref> Fire, fueled with [[wood]] and [[charcoal]], allowed early humans to cook their food to increase its digestibility, improving its nutrient value and broadening the number of foods that could be eaten.<ref>{{cite journal | last=Stahl | first= Ann B. | year=1984 | title=Hominid dietary selection before fire | journal=[[Current Anthropology]] | volume=25 | pages= 151\u201368 | doi=10.1086/203106 | issue=2 | jstor=2742818| s2cid= 84337150 }}</ref>\n\n Other technological advances made during the Paleolithic era were [[clothing]] and shelter; the adoption of both technologies cannot be dated exactly, but they were a key to humanity's progress. As the Paleolithic era progressed, dwellings became more sophisticated and more elaborate; as early as 380 ka, humans were constructing temporary wood huts.<ref>{{cite web | url=http://anthro.palomar.edu/homo2/mod_homo_3.htm | title=Evolution of Modern Humans: Archaic Homo sapiens Culture | access-date=31 March 2007 | author=O'Neil, Dennis | publisher=[[Palomar College]] | archive-url=https://web.archive.org/web/20070404130017/http://anthro.palomar.edu/homo2/mod_homo_3.htm | archive-date=4 April 2007 | url-status=live | df=dmy-all }}</ref><ref>{{cite book | last=Villa | first=Paola | year=1983 | title=Terra Amata and the Middle Pleistocene archaeological record of southern France| publisher=[[University of California Press]] |location=[[Berkeley, California|Berkeley]] | isbn= 978-0-520-09662-2 |page= 303}}</ref> Clothing, adapted from the fur and hides of hunted animals, helped humanity expand into colder regions; humans began to [[Historical migration|migrate]]\nout of Africa by 200 ka and into other continents such as [[Eurasia]].<ref>{{cite journal|last=Cordaux|first=Richard|year=2003|title=South Asia, the Andamanese, and the Genetic Evidence for an 'Early' Human Dispersal out of Africa|url=http://site.voila.fr/rcordaux/pdfs/04.pdf|journal=[[American Journal of Human Genetics]]|volume=72|issue=6|pages=1586\u201390; author reply 1590\u201393|doi=10.1086/375407|pmc=1180321|pmid=12817589|author2=Stoneking, Mark|access-date=22 May 2007|archive-url=https://web.archive.org/web/20091001022940/http://site.voila.fr/rcordaux/pdfs/04.pdf|archive-date=1 October 2009|url-status=live|df=dmy-all}}</ref>\n\n [[File:N\u00e9olithique 0001.jpg|thumb|An array of Neolithic artifacts, including bracelets, axe heads, chisels, and polishing tools]]\n\nHuman's technological ascent began in earnest in what is known as the [[Neolithic]] Period ("New Stone Age"). The invention of polished [[stone axe]]s was a major advance that allowed [[deforestation|forest clearance]] on a large scale to create farms. This use of polished stone axes increased greatly in the Neolithic, but were originally used in the preceding [[Mesolithic]] in some areas such as [[Ireland]].<ref>{{cite book|last1=Driscoll|first1=Killian|title=The early prehistory in the west of Ireland: Investigations into the social archaeology of the Mesolithic, west of the Shannon, Ireland|date=2006|url=http://lithicsireland.ie/mlitt_mesolithic_west_ireland_chap_2.html|access-date=11 July 2017|archive-url=https://web.archive.org/web/20170904110326/http://lithicsireland.ie/mlitt_mesolithic_west_ireland_chap_2.html|archive-date=4 September 2017|url-status=live|df=dmy-all}}</ref> [[Agriculture]] fed larger populations, and the transition to [[sedentism]] allowed simultaneously raising more children, as infants no longer needed to be carried, as [[nomad]]ic ones must. Additionally, children could contribute labor to the raising of crops more readily than they could to the [[hunter-gatherer]] economy.<ref>{{Cite news|url=https://www.sciencedaily.com/releases/2006/01/060103114116.htm|title=The First Baby Boom: Skeletal Evidence Shows Abrupt Worldwide Increase In Birth Rate During Neolithic Period|last=University of Chicago Press Journals|date=4 January 2006|work=ScienceDaily|access-date=7 November 2016|archive-url=https://web.archive.org/web/20161108133752/https://www.sciencedaily.com/releases/2006/01/060103114116.htm|archive-date=8 November 2016|url-status=live|df=dmy-all}}</ref><ref>{{cite journal|title=Child Transport, Family Size, and Increase in Human Population During the Neolithic|journal=[[Current Anthropology]]|author=Sussman, Robert W. |author2=Hall, Roberta L. |volume=13|issue=2| pages=258\u201367|date=April 1972|doi=10.1086/201274 |jstor=2740977|s2cid=143449170}}</ref>\n\nWith this increase in population and availability of labor came an increase in [[labor specialization]].<ref>{{cite book|access-date=17 May 2008|url=https://books.google.com/books?id=isGyuX9motEC&q=labor+neolithic+population&pg=PA163|title=Cultural Anthropology: An Applied Perspective|publisher=[[The Thomson Corporation]]|author=Ferraro, Gary P.|year=2006|isbn=978-0-495-03039-3|archive-date=31 March 2021|archive-url=https://web.archive.org/web/20210331145412/https://books.google.com/books?id=isGyuX9motEC&q=labor+neolithic+population&pg=PA163|url-status=live}}</ref> What triggered the progression from early Neolithic villages to the first cities, such as [[Uruk]], and the first civilizations, such as [[Sumer]], is not specifically known; however, the emergence of increasingly [[hierarchy|hierarchical]] social structures and specialized labor, of trade and war amongst adjacent cultures, and the need for collective action to overcome environmental challenges such as [[irrigation]], are all thought to have played a role.<ref>{{cite book|url=https://books.google.com/books?id=8pKKwlEcpwYC&q=labor+surplus+neolithic+population&pg=PA7|access-date=17 May 2008|title=The ESSENTIALS of Ancient History|publisher=Research & Education Association|author=Patterson, Gordon M.|year=1992|isbn=978-0-87891-704-4|archive-date=31 March 2021|archive-url=https://web.archive.org/web/20210331145419/https://books.google.com/books?id=8pKKwlEcpwYC&q=labor+surplus+neolithic+population&pg=PA7|url-status=live}}</ref>\n\n Continuing improvements led to the [[Metallurgical furnace|furnace]] and [[bellows]] and provided, for the first time, the ability to [[smelting|smelt]] and [[forging|forge]] [[gold]], [[copper]], [[silver]], and [[lead]] {{spaced ndash}}native metals found in relatively pure form in nature.<ref>{{Cite journal|title=A Short History of Metals |journal=Nature |volume=203 |issue=4943 |pages=337 |last=Cramb |first=Alan W |bibcode=1964Natur.203Q.337T |year=1964 |doi=10.1038/203337a0 |s2cid=382712 |doi-access=free }}</ref> The advantages of copper tools over stone, bone, and wooden tools were quickly apparent to early humans, and native copper was probably used from near the beginning of [[Neolithic]] times (about 10 ka).<ref>{{cite EB1911|wstitle= Ceramics |volume= 05 | pages = 703–760; see page 708 |last1= Hall |first1= Harry Reginald Holland |author-link= Harry Reginald Holland Hall |quote= The art of making a pottery consisting of a siliceous sandy body coated with a vitreous copper glaze seems to have been known unexpectedly early, possibly even as early as the period immediately preceding the Ist Dynasty (4000 B.C.).}}</ref> Native copper does not naturally occur in large amounts, but copper ores are quite common and some of them produce metal easily when burned in wood or charcoal fires. Eventually, the working of metals led to the discovery of [[alloys]] such as [[bronze]] and [[brass]] (about 4000 BCE). The first uses of iron alloys such as [[steel]] dates to around 1800 BCE.<ref>{{Cite journal |title=The significance of the composition of excavated iron fragments taken from Stratum III at the site of Kaman-Kaleh\u00f6y\u00fck, Turkey |journal=Anatolian Archaeological Studies |volume=14 |publisher=Japanese Institute of Anatolian Archaeology |place=Tokyo}}</ref><ref>{{Cite news|url=http://www.hindu.com/thehindu/holnus/001200903261611.htm |title=Ironware piece unearthed from Turkey found to be oldest steel |date=26 March 2009 |work=The Hindu |archive-url=https://web.archive.org/web/20090329111924/http://www.hindu.com/thehindu/holnus/001200903261611.htm |archive-date=29 March 2009 |url-status=dead |access-date=8 November 2016 }}</ref>\n\n [[File:Wheel Iran.jpg|thumb|left|upright|The [[wheel]] was invented circa 4000 BCE.]]\n{{Main|History of transport}}\nMeanwhile, humans were learning to harness other forms of energy. The earliest known use of wind power is the [[sailing ship]]; the earliest record of a ship under sail is that of a Nile boat dating to the 8th-millennium BCE.<ref>{{Cite journal|title=The oldest representation of a Nile boat|journal=Antiquity|volume=81}}</ref> From prehistoric times, Egyptians probably used the power of the annual [[flooding of the Nile]] to irrigate their lands, gradually learning to regulate much of it through purposely built irrigation channels and "catch" basins. The ancient [[Sumer]]ians in [[Mesopotamia]] used a complex system of canals and levees to divert water from the [[Tigris]] and [[Euphrates]] rivers for irrigation.<ref>{{cite book|last=Crawford|first=Harriet|date=2013|title=The Sumerian World|location=New York City, New York and London, England|publisher=Routledge|isbn=978-0-203-09660-4|pages=34\u201343|url=https://books.google.com/books?id=qSOYAAAAQBAJ&q=Sumerian+irrigation&pg=PA35|access-date=12 November 2020|archive-date=5 December 2020|archive-url=https://web.archive.org/web/20201205005423/https://books.google.com/books?id=qSOYAAAAQBAJ&q=Sumerian+irrigation&pg=PA35|url-status=live}}</ref>\n\n[[File:Gibson Technology GL458.jpg|thumb|Gibson Technology GL458]]\n\nAccording to archaeologists, the [[wheel]] was invented around 4000 BCE probably independently and nearly simultaneously in Mesopotamia (in present-day [[Iraq]]), the Northern Caucasus ([[Maykop culture]]) and Central Europe.<ref>{{Cite book|title=A Companion to the Archaeology of the Ancient Near East|last=Potts|first=D.T.|year=2012|page=285}}</ref> Estimates on when this may have occurred range from 5500 to 3000 BCE with most experts putting it closer to 4000 BCE.<ref>{{Cite book|title=New Light on the Most Ancient East|last=Childe|first=V. Gordon|year=1928|page=110}}</ref> The oldest artifacts with drawings depicting wheeled carts date from about 3500 BCE;<ref>{{Cite book|title=The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World|last=Anthony|first=David A.|publisher=Princeton University Press|year=2007|isbn=978-0-691-05887-0|location=Princeton|page=67}}</ref> however, the wheel may have been in use for millennia before these drawings were made. More recently, the oldest-known wooden wheel in the world was found in the Ljubljana marshes of Slovenia.<ref>{{cite web|url=http://www.ukom.gov.si/en/media_room/background_information/culture/worlds_oldest_wheel_found_in_slovenia/|title=World's Oldest Wheel Found in Slovenia|last=Gasser|first=Aleksander|date=March 2003|publisher=Republic of Slovenia Government Communication Office|access-date=8 November 2016|archive-url=https://web.archive.org/web/20160826021129/http://www.ukom.gov.si/en/media_room/background_information/culture/worlds_oldest_wheel_found_in_slovenia/|archive-date=26 August 2016|url-status=dead|df=dmy-all}}</ref>\n\nThe invention of the wheel revolutionized trade and war. It did not take long to discover that wheeled wagons could be used to carry heavy loads. The ancient Sumerians used the [[potter's wheel]] and may have invented it.<ref name=Kramer1963>{{cite book|last=Kramer|first=Samuel Noah|date=1963|title=The Sumerians: Their History, Culture, and Character|url=https://books.google.com/books?id=IuxIdug8DBUC|publisher=University of Chicago Press|location=Chicago, Illinois|isbn=978-0-226-45238-8|page=290|access-date=26 October 2017|archive-url=https://web.archive.org/web/20140808201642/http://books.google.com/books/about/The_Sumerians.html?id=IuxIdug8DBUC|archive-date=8 August 2014|url-status=live|df=dmy-all}}</ref> A stone pottery wheel found in the city-state of [[Ur]] dates to around 3429 BCE,<ref name=Moorey1994>{{cite book|last=Moorey|first=Peter Roger Stuart|date=1999|orig-year=1994|title=Ancient Mesopotamian Materials and Industries: The Archaeological Evidence|url=https://books.google.com/books?id=P_Ixuott4doC|location=Winona Lake, Indiana|publisher=Eisenbrauns|isbn=978-1-57506-042-2|page=146|access-date=26 October 2017|archive-url=https://web.archive.org/web/20171017215042/https://books.google.com/books/about/Ancient_Mesopotamian_Materials_and_Indus.html?id=P_Ixuott4doC|archive-date=17 October 2017|url-status=live|df=dmy-all}}</ref> and even older fragments of wheel-thrown pottery have been found in the same area.<ref name=Moorey1994/> Fast (rotary) potters' wheels enabled early [[mass production]] of pottery, but it was the use of the wheel as a transformer of energy (through [[water wheel]]s, windmills, and even treadmills) that revolutionized the application of nonhuman power sources. The first two-wheeled carts were derived from [[travois]]<ref name=Lay1992>{{cite book|last=Lay|first=M G |title=Ways of the World|publisher=Primavera Press|year=1992|location=Sydney, Australia|page=28|isbn=978-1-875368-05-1}}</ref> and were first used in Mesopotamia and [[Iran]] in around 3000 BCE.<ref name=Lay1992/>\n\nThe oldest known constructed roadways are the stone-paved streets of the city-state of Ur, dating to circa 4000 BCE<ref name="Gregersen2012">{{cite book|last1=Gregersen|first1=Erik|title=The Complete History of Wheeled Transportation: From Cars and Trucks to Buses and Bikes|date=2012|publisher=Britannica Educational Publishing|location=New York City, New York|isbn=978-1-61530-701-2|page=130|url=https://books.google.com/books?id=ldSbAAAAQBAJ&q=paved+road+in+Ur&pg=PA130|access-date=12 November 2020|archive-date=31 March 2021|archive-url=https://web.archive.org/web/20210331145500/https://books.google.com/books?id=ldSbAAAAQBAJ&q=paved+road+in+Ur&pg=PA130|url-status=live}}</ref> and timber roads leading through the swamps of [[Glastonbury, England]], dating to around the same time period.<ref name="Gregersen2012"/> The first long-distance road, which came into use around 3500 BCE,<ref name="Gregersen2012"/> spanned 1,500 miles from the [[Persian Gulf]] to the [[Mediterranean Sea]],<ref name="Gregersen2012"/> but was not paved and was only partially maintained.<ref name="Gregersen2012"/> In around 2000 BCE, the [[Minoan civilization|Minoans]] on the Greek island of [[Crete]] built a fifty-kilometer (thirty-mile) road leading from the palace of [[Gortyn]] on the south side of the island, through the mountains, to the palace of [[Knossos]] on the north side of the island.<ref name="Gregersen2012"/> Unlike the earlier road, the Minoan road was completely paved.<ref name="Gregersen2012"/>\n\n [[File:Pont du Gard BLS.jpg|thumb|upright=1.3|Photograph of the [[Pont du Gard]] in France, one of the most famous [[Roman aqueduct|ancient Roman aqueducts]]<ref name="Aicher1995"/>]]\nAncient Minoan private homes had [[running water]].<ref name=Eslamian2014>{{cite book|last1=Eslamian|first1=Saeid|title=Handbook of Engineering Hydrology: Environmental Hydrology and Water Management|date=2014|publisher=CRC Press|location=Boca Raton, Florida|isbn=978-1-4665-5250-0|pages=171\u201375|url=https://books.google.com/books?id=USXcBQAAQBAJ&q=Minoan+flush+toilet&pg=PA174|access-date=12 November 2020|archive-date=10 December 2020|archive-url=https://web.archive.org/web/20201210095408/https://books.google.com/books?id=USXcBQAAQBAJ&q=Minoan+flush+toilet&pg=PA174|url-status=live}}</ref> A bathtub virtually identical to modern ones was unearthed at the Palace of Knossos.<ref name=Eslamian2014/><ref name="Lechner2012">{{cite book|last1=Lechner|first1=Norbert|title=Plumbing, Electricity, Acoustics: Sustainable Design Methods for Architecture|date=2012|publisher=John Wiley & Sons, Inc.|location=Hoboken, New Jersey|isbn=978-1-118-01475-2|page=106|url=https://books.google.com/books?id=0loW1G-Q5f4C&q=Minoan+flush+toilet&pg=PA106|access-date=12 November 2020|archive-date=31 March 2021|archive-url=https://web.archive.org/web/20210331145421/https://books.google.com/books?id=0loW1G-Q5f4C&q=Minoan+flush+toilet&pg=PA106|url-status=live}}</ref> Several Minoan private homes also had [[toilet]]s, which could be flushed by pouring water down the drain.<ref name=Eslamian2014/> The ancient Romans had many public flush toilets,<ref name="Lechner2012"/> which emptied into an extensive [[sewage system]].<ref name="Lechner2012"/> The primary sewer in Rome was the [[Cloaca Maxima]];<ref name="Lechner2012"/> construction began on it in the sixth century BCE and it is still in use today.<ref name="Lechner2012"/>\n\nThe ancient Romans also had a complex system of [[aqueduct (bridge)|aqueducts]],<ref name="Aicher1995">{{cite book|last1=Aicher|first1=Peter J.|title=Guide to the Aqueducts of Ancient Rome|date=1995|publisher=Bolchazy-Carducci Publishers, Inc.|location=Wauconda, Illinois|isbn=978-0-86516-282-2|page=6|url=https://books.google.com/books?id=IEa04PmWXq0C&q=Pont+du+Gard|access-date=12 November 2020|archive-date=5 December 2020|archive-url=https://web.archive.org/web/20201205010425/https://books.google.com/books?id=IEa04PmWXq0C&q=Pont+du+Gard|url-status=live}}</ref> which were used to transport water across long distances.<ref name="Aicher1995"/> The first [[Roman aqueduct]] was built in 312 BCE.<ref name="Aicher1995"/> The eleventh and final ancient Roman aqueduct was built in 226 CE.<ref name="Aicher1995"/> Put together, the Roman aqueducts extended over 450 kilometers,<ref name="Aicher1995"/> but less than seventy kilometers of this was above ground and supported by arches.<ref name="Aicher1995"/>\n\n {{Main|Medieval technology|Renaissance technology|Industrial Revolution|Second Industrial Revolution|Information Technology|Productivity improving technologies (economic history)}}\n[[File:Schlagwortkatalog.jpg | thumb | The [[card catalog]], a technology developed in the 19th century, became ubiquitous in the 20th century.]]\n\nInnovations continued through the [[Middle Ages]] with innovations such as [[silk]]-manufacture (introduced into Europe after centuries of development in Asia), the [[horse collar]] and [[horseshoe]]s in the first few hundred years after the 5th-century fall of the [[Western Roman Empire|Roman Empire]]. [[Medieval technology]] saw the use of [[simple machine]]s (such as the [[lever]], the [[screw]], and the [[pulley]]) being combined to form more complicated tools, such as the [[wheelbarrow]], [[windmill]]s and [[clock]]s, and a system of [[University|universities]] developed and spread scientific ideas and practices. The [[Renaissance technology|Renaissance]] era produced many innovations, including the [[printing press]] (which facilitated the communication of knowledge), and technology became increasingly associated with [[science]], beginning a cycle of mutual advancement. Advances in technology in this era allowed a more reliable supply of food, followed by the wider availability of [[consumer goods]].\n\n[[File:Late model Ford Model T.jpg|thumb|upright=0.8|left|The [[automobile]] revolutionized personal transportation.]]\nStarting in the United Kingdom in the 18th century, the [[Industrial Revolution]] was a period of great technological discovery, particularly in the areas of [[British Agricultural Revolution|agriculture]], [[manufacturing]], [[mining]], [[metallurgy]], and [[transport]], driven by the discovery of [[steam power]] and the widespread application of the [[factory system]]. Technology took another step in a [[second industrial revolution]] ({{circa | 1870}} to {{circa | 1914}}) with the harnessing of [[electricity]] to allow such innovations as the [[electric motor]], [[light bulb]], and countless others. Scientific advances and the discovery of new concepts later allowed for [[aviation|powered flight]] and developments in [[medicine]], [[chemistry]], [[physics]], and [[engineering]]. The rise in technology has led to [[skyscraper]]s and broad [[urban area]]s whose inhabitants rely on [[motor]]s to transport them and their food supplies. Communication improved with the invention of the [[telegraph]], [[telephone]], [[radio]] and [[television]]. The late-19th and early-20th centuries saw a revolution in transportation with the invention of the [[airplane]] and [[automobile]].\n\n[[File:USAF F-16A F-15C F-15E Desert Storm edit2.jpg|thumb|[[F-15]] and [[F-16]] flying over [[Kuwaiti oil fires]] during the [[Gulf War]] in 1991.]]\nThe 20th century brought a host of innovations. In [[physics]], the discovery of [[nuclear fission]] has led to both [[nuclear weapons]] and [[nuclear power]]. [[Computers]] were invented and later [[miniaturization|miniaturized]] using [[transistor]]s and [[integrated circuit]]s. [[Information technology]], particularly the [[optical fiber]] and [[Optical amplifier|optical amplifiers]] that led to the birth of the [[Internet]], which ushered in the [[Information Age]]. Humans started to [[space exploration|explore space]] with [[satellite]]s (late 1950s, later used for [[telecommunication]]) and in crewed missions (1960s) going all the way to the moon. In medicine, this era brought innovations such as [[Cardiac surgery|open-heart surgery]] and later [[stem cell treatments|stem-cell therapy]] along with new [[pharmaceutical drug|medications]] and treatments using [[genomics]].\n\nComplex [[manufacturing]] and [[construction]] techniques and organizations are needed to make and maintain some of the newer technologies, and entire [[Industry (economics)|industries]] have arisen to support and develop succeeding generations of increasingly more complex tools. Modern technology increasingly relies on training and education \u2013 their designers, builders, maintainers, and users often require sophisticated general and specific training. Moreover, these technologies have become so complex that entire fields have developed to support them, including [[engineering]], [[medicine]], and [[computer science]]; and other fields have become more complex, such as [[construction]], [[transportation]], and [[architecture]]."}},
{"article_title": "Television", "pageid": "29831", "revid": "1062842397", "timestamp": "2021-12-30T21:35:10Z", "history_paths": [["Television --- Introduction ---", "History"]], "categories": ["television", "advertising by medium", "television terminology", "media formats", "broadcasting", "consumer electronics", "digital technology", "performing arts", "video hardware", "1925 in technology", "1927 in technology", "telecommunications-related introductions in 1925", "telecommunications-related introductions in 1927", "american inventions", "british inventions", "german inventions", "russian inventions", "television industry", "1925 introductions", "1927 introductions", "20th-century inventions"], "heading_tree": {"Television --- Introduction ---": {"Etymology": {}, "History": {"Mechanical": {}, "Electronic": {}, "Color": {}, "Digital": {}, "Smart television": {}, "3D": {}}, "Broadcast systems": {"Terrestrial television": {}, "Cable television": {}, "Satellite television": {}, "Internet television": {}}, "Sets": {"Display technologies": {"Disk": {}, "CRT": {}, "DLP": {}, "Plasma": {}, "LCD": {}, "OLED": {}}, "Display resolution": {"LD": {}, "SD": {}, "HD": {}, "UHD": {}}, "Market share": {}}, "Content": {"Programming": {}, "Genres": {}, "Funding": {"Advertising": {}, "United States": {}, "United Kingdom": {}, "Ireland": {}, "Subscription": {}, "Taxation or license": {}}, "Broadcast programming": {}}, "Social aspects": {"Opposition": {}}, "Negative impacts": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Television --- Introduction ---|History": "{{Main|History of television}}\n\n {{main|Mechanical television}}\n[[File:Nipkow disk.svg|right|upright=0.9|thumb|The [[Nipkow disk]]. This schematic shows the circular paths traced by the holes that may also be square for greater precision. The area of the disk outlined in black displays the region scanned.]]\n\n[[Facsimile transmission]] systems for still photographs pioneered methods of mechanical scanning of images in the early 19th century. [[Alexander Bain (inventor)|Alexander Bain]] introduced the facsimile machine between 1843 and 1846. [[Frederick Bakewell]] demonstrated a working laboratory version in 1851.{{Citation needed|date=May 2015}} [[Willoughby Smith]] discovered the [[photoconductivity]] of the element [[selenium]] in 1873. As a 23-year-old German university student, [[Paul Nipkow|Paul Julius Gottlieb Nipkow]] proposed and patented the [[Nipkow disk]] in 1884.<ref>Shiers, George and May (1997), ''Early Television: A Bibliographic Guide to 1940''. Taylor & Francis, pp. 13, 22. {{ISBN|978-0-8240-7782-2}}.</ref> This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image. Although he never built a working model of the system, variations of Nipkow's spinning-disk "[[rasterizer|image rasterizer]]" became exceedingly common.<ref>Shiers & Shiers, p. 13, 22.</ref> [[Constantin Perskyi]] had coined the word ''television'' in a paper read to the International Electricity Congress at the [[Exposition Universelle (1900)|International World Fair]] in Paris on 24 August 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others.<ref>{{cite web|author=Constantin PERSKYI|url=https://www.histv.net/perskyi-1900|title=T\u00e9l\u00e9vision au moyen de l'\u00e9lectricit\u00e9|agency=Congr\u00e8s Inographs by Telegraph|work=The New York Times Sunday Magazine|date=20 September 1907|page= 7}}</ref> However, it was not until 1907 that developments in amplification tube technology by [[Lee de Forest]] and [[Arthur Korn]], among others, made the design practical.<ref name="Sending Photographs by Telegraph">[https://query.nytimes.com/gst/abstract.html?res=9A07E4DA1331E733A25757C2A9649C946697D6CF "Sending Photographs by Telegraph"], ''The New York Times'', Sunday Magazine, 20 September 1907, p. 7.</ref>\n\nThe first demonstration of the live transmission of images was by Georges Rignoux and A. Fournier in Paris in 1909. A matrix of 64 [[selenium]] cells, individually wired to a mechanical [[commutator (electric)|commutator]], served as an electronic [[retina]]. In the receiver, a type of [[Kerr effect|Kerr cell]] modulated the light and a series of differently angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. A separate circuit regulated synchronization. The 8x8 [[pixel]] resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet. An updated image was transmitted "several times" each second.<ref>Henry de Varigny, "[http://histv2.free.fr/rignoux/rignoux1909.htm La vision \u00e0 distance] {{Webarchive|url=https://web.archive.org/web/20160303231305/http://histv2.free.fr/rignoux/rignoux1909.htm |date=3 March 2016 }}", ''L'Illustration'', Paris, 11 December 1909, p. 451.</ref>\n\nIn 1911, [[Boris Rosing]] and his student [[Vladimir Zworykin]] created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "[[Karl Ferdinand Braun|Braun]] tube" ([[cathode ray tube]] or "CRT") in the receiver. Moving images were not possible because, in the scanner: "the sensitivity was not enough and the selenium cell was very laggy".<ref>[https://books.google.com/books?id=gZcwhVyiMqsC&printsec=frontcover&dq=Burns+%27%27Television:+An+International+History+of+the+Formative+Years%22&cd=1#v=onepage&q=zworykin%20rosing%20selenium&f=false R. W. Burns, ''Television: An International History of the Formative Years''], IET, 1998, p. 119. {{ISBN|0-85296-914-7}}.</ref>\n\nIn 1921, [[Edouard Belin]] sent the first image via radio waves with his [[belinograph]].<ref name="Corporation1921">{{cite book|chapter-url=https://books.google.com/books?id=aSoDAAAAMBAJ&pg=PA21|title=Popular Science|author=Wilfred S. Ogden|date=December 1921|publisher=Bonnier Corporation|pages=21\u201322|chapter=How the World's First Wireless News-Picture Was Flashed Across the Atlantic Ocean, Paris get President Harding's portrait in twenty minutes|journal=The Popular Science Monthly|issn=0161-7370|access-date=2 July 2014}}</ref>\n\n[[File:John Logie Baird and Stooky Bill.png|thumb|left|upright=0.9|[[John Logie Baird|Baird]] in 1925 with his televisor equipment and dummies "James" and "Stooky Bill" ''(right)''.]]\n<!-- [[WP:NFCC]] violation: [[File:John Logie Baird, 1st Image.jpg|thumb|left|upright=0.9|The first known photograph of a moving image produced by Baird's "televisor", circa 1926 (The subject is Baird's business partner Oliver Hutchinson)]] -->\n\nBy the 1920s, when amplification made television practical, Scottish inventor [[John Logie Baird]] employed the Nipkow disk in his prototype video systems. On 25 March 1925, Baird gave the first public demonstration of televised [[silhouette]] images in motion, at [[Selfridges|Selfridge's]] Department Store in London.<ref>{{Cite journal |doi=10.1038/115504a0|title=Current Topics and Events|journal=Nature|volume=115|issue=2892|pages=504\u2013508|year=1925|bibcode=1925Natur.115..504.|doi-access=free}}</ref> Since human faces had inadequate contrast to show up on his primitive system, he televised a ventriloquist's dummy named "Stooky Bill", whose painted face had higher contrast, talking and moving. By 26 January 1926, he had demonstrated the transmission of an image of a face in motion by radio. This is widely regarded as the world's first public television demonstration. Baird's system used the Nipkow disk for both scanning the image and displaying it. A brightly illuminated subject was placed in front of a spinning Nipkow disk set with lenses which swept images across a static photocell. The thallium sulphide (Thalofide) cell, developed by Theodore Case in the U.S., detected the light reflected from the subject and converted it into a proportional electrical signal. This was transmitted by AM radio waves to a receiver unit, where the video signal was applied to a neon light behind a second Nipkow disk rotating synchronized with the first. The brightness of the neon lamp was varied in proportion to the brightness of each spot on the image. As each hole in the disk passed by, one [[scan line]] of the image was reproduced. Baird's disk had 30 holes, producing an image with only 30 scan lines, just enough to recognize a human face.{{Citation needed|date=April 2021}} In 1927, Baird transmitted a signal over {{convert|438|mi|km}} of telephone line between London and [[Glasgow]].<ref>{{cite web|url=http://www.bbc.co.uk/history/historic_figures/baird_logie.shtml#:~:text=On%2026%20January%201926%20he,the%20Baird%20Television%20Development%20Company.|title=John Logie Baird (1888 - 1946)|work=[[BBC]]|accessdate=7 April 2021}}</ref>\n\nIn 1928, Baird's company (Baird Television Development Company/Cinema Television) broadcast the first transatlantic television signal, between London and New York, and the first shore-to-ship transmission. In 1929, he became involved in the first experimental mechanical television service in Germany. In November of the same year, Baird and [[Bernard Natan]] of [[Path\u00e9]] established France's first television company, T\u00e9l\u00e9vision-[[John Logie Baird|Baird]]-Natan. In 1931, he made the first outdoor remote broadcast, of [[Epsom Derby|The Derby]].<ref>J. L. Baird, "[http://www.bairdtelevision.com/1932.html Television in 1932]", ''BBC Annual Report'', 1933.</ref> In 1932, he demonstrated [[ultra-short wave]] television. Baird's mechanical system reached a peak of 240-lines of resolution on [[BBC]] telecasts in 1936, though the mechanical system did not scan the televised scene directly. Instead a [[17.5mm film]] was shot, rapidly developed and then scanned while the film was still wet.{{Citation needed|date=August 2019}}\n\nA U.S. inventor, [[Charles Francis Jenkins]], also pioneered the television. He published an article on "Motion Pictures by Wireless" in 1913, but it was not until December 1923 that he transmitted moving silhouette images for witnesses; and it was on 13 June 1925, that he publicly demonstrated synchronized transmission of silhouette pictures. In 1925 Jenkins used the Nipkow disk and transmitted the silhouette image of a toy windmill in motion, over a distance of 5 miles (8 km), from a naval radio station in Maryland to his laboratory in Washington, D.C., using a lensed disk scanner with a 48-line resolution.<ref>"Radio Shows Far Away Objects in Motion", ''The New York Times'', 14 June 1925, p. 1.</ref><ref name="glinsky">{{cite book| last = Glinsky| first = Albert| title = Theremin: Ether Music and Espionage| location = Urbana, Illinois| publisher = University of Illinois Press| year = 2000| pages = [https://archive.org/details/thereminethermus00glin/page/41 41]\u201345| isbn = 978-0-252-02582-2| url = https://archive.org/details/thereminethermus00glin| url-access = registration}}</ref> He was granted [[United States Patent and Trademark Office|U.S. Patent]] No. 1,544,156 (Transmitting Pictures over Wireless) on 30 June 1925 (filed 13 March 1922).<ref>{{cite web |title=Case Files: Francis Jenkins (Phantoscope) |url=https://www.fi.edu/case-files/francis-jenkins-phantoscope |website=[[The Franklin Institute]] |date=27 May 2016 |access-date=28 March 2020}}</ref>\n\n[[Herbert E. Ives]] and [[Frank Gray (researcher)|Frank Gray]] of [[Bell Labs|Bell Telephone Laboratories]] gave a dramatic demonstration of mechanical television on 7 April 1927. Their reflected-light television system included both small and large viewing screens. The small receiver had a 2-inch-wide by 2.5-inch-high screen (5 by 6 cm). The large receiver had a screen 24 inches wide by 30 inches high (60 by 75 cm). Both sets were capable of reproducing reasonably accurate, monochromatic, moving images. Along with the pictures, the sets received synchronized sound. The system transmitted images over two paths: first, a [[copper wire]] link from Washington to New York City, then a radio link from [[Whippany, New Jersey]]. Comparing the two transmission methods, viewers noted no difference in quality. Subjects of the telecast included [[Secretary of Commerce]] [[Herbert Hoover]]. A [[flying-spot scanner]] beam illuminated these subjects. The scanner that produced the beam had a 50-aperture disk. The disc revolved at a rate of 18 frames per second, capturing one frame about every 56 [[millisecond]]s. (Today's systems typically transmit 30 or 60 frames per second, or one frame every 33.3 or 16.7 milliseconds respectively.) Television historian Albert Abramson underscored the significance of the Bell Labs demonstration: "It was in fact the best demonstration of a mechanical television system ever made to this time. It would be several years before any other system could even begin to compare with it in picture quality."<ref>Abramson, Albert, ''The History of Television, 1880 to 1941'', McFarland & Co., Inc., 1987, p. 101. {{ISBN|978-0-89950-284-7}}.</ref>\n\nIn 1928, [[WRGB]], then W2XB, was started as the world's first television station. It broadcast from the [[General Electric]] facility in [[Schenectady, NY]]. It was popularly known as "[[WGY (AM)|WGY]] Television". Meanwhile, in the [[Soviet Union]], [[L\u00e9on Theremin]] had been developing a mirror drum-based television, starting with 16 lines resolution in 1925, then 32 lines and eventually 64 using [[interlaced video|interlacing]] in 1926. As part of his thesis, on 7 May 1926, he electrically transmitted, and then projected, near-simultaneous moving images on a {{convert|5|ft2|adj=on}} screen.<ref name="glinsky"/>\n\nBy 1927, Theremin had achieved an image of 100 lines, a resolution that was not surpassed until May 1932 by RCA, with 120 lines.<ref>{{cite web | url=http://www.earlytelevision.org/rca_story_brewster.html | title=Early Electronic Television RCA TV Development: 1929\u20131949 | publisher=Early Television Museum | access-date=20 February 2016 | author=Brewster, Richard}}</ref>\n\nOn 25 December 1926, [[Kenjiro Takayanagi]] demonstrated a television system with a 40-line resolution that employed a Nipkow disk scanner and CRT display at Hamamatsu Industrial High School in Japan. This prototype is still on display at the Takayanagi Memorial Museum in [[Shizuoka University]], Hamamatsu Campus. His research in creating a production model was halted by the [[Supreme Commander for the Allied Powers|SCAP]] after [[World War II]].<ref name="nhk.or.jp">[http://www.nhk.or.jp/strl/aboutstrl/evolution-of-tv-en/p05/ ''Kenjiro Takayanagi: The Father of Japanese Television''] {{webarchive|url=https://web.archive.org/web/20160101180643/http://www.nhk.or.jp/strl/aboutstrl/evolution-of-tv-en/p05/ |date=1 January 2016 }}, NHK (Japan Broadcasting Corporation), 2002. Retrieved 23 May 2009.</ref>\n\nBecause only a limited number of holes could be made in the disks, and disks beyond a certain diameter became impractical, image resolution on mechanical television broadcasts was relatively low, ranging from about 30 lines up to 120 or so. Nevertheless, the image quality of 30-line transmissions steadily improved with technical advances, and by 1933 the UK broadcasts using the Baird system were remarkably clear.<ref>Donald F. McLean, ''Restoring Baird's Image'' (London: IEEE, 2000), p. 184.</ref> A few systems ranging into the 200-line region also went on the air. Two of these were the 180-line system that Compagnie des Compteurs (CDC) installed in Paris in 1935, and the 180-line system that [[Peck Television Corp.]] started in 1935 at station VE9AK in [[Montreal]].<ref>{{cite web|url=http://www.earlytelevision.org/ve9ak.html |title=VE9AK entry at |publisher=Earlytelevision.org |access-date=2 March 2010}}</ref><ref>{{cite web|title=Peck Television Corporation Console Receiver and Camera|url=http://www.earlytelevision.org/peck.html|publisher=Early Television Museum|access-date=18 February 2012}}</ref> The advancement of all-electronic television (including [[Video camera tube#Image dissector|image dissectors]] and other camera tubes and [[cathode ray tube]]s for the reproducer) marked the start of the end for mechanical systems as the dominant form of television. Mechanical television, despite its inferior image quality and generally smaller picture, would remain the primary television technology until the 1930s. The last mechanical telecasts ended in 1939 at stations run by a lot of public universities in the United States.\n\n {{See|Video camera tube}}\n\nIn 1897, English [[physicist]] [[J. J. Thomson]] was able, in his three well-known experiments, to deflect cathode rays, a fundamental function of the modern [[cathode ray tube]] (CRT). The earliest version of the CRT was invented by the German physicist [[Ferdinand Braun]] in 1897 and is also known as the "Braun" tube.<ref>Ferdinand Braun (1897) [https://archive.today/20141217172841/http://babel.hathitrust.org/cgi/pt?id=wu.89048352892;view=1up;seq=568 "Ueber ein Verfahren zur Demonstration und zum Studium des zeitlichen Verlaufs variabler Str\u00f6me"] (On a process for the display and study of the course in time of variable currents), ''Annalen der Physik und Chemie'', 3rd series, '''60''' : 552\u201359.</ref> It was a [[cold cathode|cold-cathode]] [[diode]], a modification of the [[Crookes tube]], with a [[phosphor]]-coated screen. In 1906 the Germans Max Dieckmann and Gustav Glage produced [[Raster scan|raster images]] for the first time in a CRT.<ref>{{cite web|url=http://www.televisionheaven.co.uk/television_timeline_1.htm|title=Television Timeline 1812\u20131923 \u2013 Television Heaven|first=Laurence|last=Marcus}}</ref> In 1907, Russian scientist [[Boris Rosing]] used a CRT in the receiving end of an experimental [[video signal]] to form a picture. He managed to display simple geometric shapes onto the screen.<ref name="crthistory">{{cite web|url=http://inventors.about.com/od/cstartinventions/a/CathodeRayTube.htm |title=History of the Cathode Ray Tube |access-date=4 October 2009 |work=About.com }}</ref>\n\nIn 1908 [[Alan Archibald Campbell-Swinton]], fellow of the [[Royal Society]] (UK), published a letter in the scientific journal ''[[Nature (journal)|Nature]]'' in which he described how "distant electric vision" could be achieved by using a cathode ray tube, or Braun tube, as both a transmitting and receiving device,<ref name="Swinton_DEV1">\n{{cite journal\n | author = Campbell-Swinton, A. A.\n | title = Distant Electric Vision (first paragraph)\n | journal = Nature\n | volume = 78\n | issue = 2016\n | page = 151\n | date = 18 June 1908\n| doi=10.1038/078151a0| bibcode = 1908Natur..78..151S\n | s2cid = 3956737\n | url = https://zenodo.org/record/1429503\n | doi-access = free\n }}\n</ref><ref name="Swinton_DEV2">\n{{cite journal\n | url = http://www.nature.com/nature/journal/v78/n2016/pdf/078151a0.pdf\n | author = Campbell-Swinton, A. A.\n | title = Distant Electric Vision\n | journal = Nature\n | volume = 78\n | page = 151\n | date = 18 June 1908\n| issue=2016\n| doi=10.1038/078151a0| bibcode = 1908Natur..78..151S\n | s2cid = 3956737\n | doi-access = free\n }}\n</ref> He expanded on his vision in a speech given in London in 1911 and reported in ''[[The Times]]''<ref>"Distant Electric Vision", ''The Times'' (London), 15 November 1911, p. 24b.</ref> and the Journal of the R\u00f6ntgen Society.<ref name="Swinton_Braid">\n{{cite web\n | url = http://www.bairdtelevision.com/swinton.html\n | title = Alan Archivald Campbell-Swinton (1863\u20131930)\n | author = Bairdtelevision\n | work = Biography\n | access-date = 10 May 2010}}\n</ref><ref name="Swinton-Rontgen">[https://books.google.com/books?id=OlXsZdT8HUQC&printsec=frontcover&dq=Early+television:+a+bibliographic+guide+to+1940&cd=1#v=onepage&q=swinton%20rontgen&f=false Shiers, George and May (1997), ''Early television: a bibliographic guide to 1940'']. New York: Garland, p. 56. Retrieved 13 June 2010.\n</ref> In a letter to ''[[Nature (journal)|Nature]]'' published in October 1926, Campbell-Swinton also announced the results of some "not very successful experiments" he had conducted with G. M. Minchin and J. C. M. Stanton. They had attempted to generate an electrical signal by projecting an image onto a selenium-coated metal plate that was simultaneously scanned by a [[cathode ray]] beam.<ref name="Swinton_ET1">\n{{cite journal\n | author = Campbell-Swinton, A. A.\n | title = Electric Television (abstract)\n | journal = Nature\n | volume = 118\n | issue = 2973\n | page = 590\n | date = 23 October 1926\n| doi=10.1038/118590a0| bibcode = 1926Natur.118..590S\n | s2cid = 4081053\n | doi-access = free\n }}\n</ref><ref name="Burns-Swinton">{{cite book\n | title = Television: An International History of the Formative Years\n | author = Burns, R W.\n | publisher = The Institute of Electrical Engineers (IEE) (History of Technology Series 22) in association with [ The Science Museum (UK)]\n | year = 1998\n | isbn = 978-0-85296-914-4\n | page = 123\n | url = https://books.google.com/books?id=gZcwhVyiMqsC&q=swinton+minchin+stanton+1903\n }}</ref> These experiments were conducted before March 1914, when Minchin died,<ref name="Minchin">\n{{cite journal\n | author = News\n | title = Prof. G.M. Minchin, F.R.S\n | journal = Nature\n | volume = 93\n | issue = 2318\n | pages = 115\u201316\n | date = 2 April 1914\n| doi = 10.1038/093115a0| bibcode = 1914Natur..93..115R\n | doi-access = free\n }}\n</ref> but they were later repeated by two different teams in 1937, by H. Miller and J. W. Strange from [[EMI]],<ref name="Miller-Strange">\n{{cite journal\n | doi = 10.1088/0959-5309/50/3/307\n |author1=Miller, H. |author2=Strange. J. W.\n |name-list-style=amp | title = The electrical reproduction of images by the photoconductive effect\n | journal = Proceedings of the Physical Society\n | volume = 50\n | issue = 3\n | pages = 374\u201384\n | date = 2 May 1938| bibcode = 1938PPS....50..374M\n }}\n</ref> and by H. Iams and A. Rose from [[RCA]].<ref name="Iams-Rose-1937">\n{{cite journal\n | doi = 10.1109/JRPROC.1937.228423\n |author1=Iams, H. |author2=Rose, A.\n |name-list-style=amp | title = Television Pickup Tubes with Cathode-Ray Beam Scanning\n | journal = Proceedings of the Institute of Radio Engineers\n | volume = 25\n | issue = 8\n | pages = 1048\u201370\n | date = August 1937|s2cid=51668505 }}\n</ref> Both teams succeeded in transmitting "very faint" images with the original Campbell-Swinton's selenium-coated plate. Although others had experimented with using a cathode ray tube as a receiver, the concept of using one as a transmitter was novel.<ref>Abramson, Albert, ''Zworykin, Pioneer of Television'', p. 16.</ref> The first cathode ray tube to use a [[hot cathode]] was developed by [[John Bertrand Johnson|John B. Johnson]] (who gave his name to the term [[Johnson\u2013Nyquist noise|Johnson noise]]) and Harry Weiner Weinhart of [[Western Electric]], and became a commercial product in 1922.{{citation needed|date=January 2011}}\n\nIn 1926, Hungarian engineer [[K\u00e1lm\u00e1n Tihanyi]] designed a television system utilizing fully electronic scanning and display elements and employing the principle of "charge storage" within the scanning (or "camera") tube.<ref>{{cite web | title = Hungary \u2013 K\u00e1lm\u00e1n Tihanyi's 1926 Patent Application 'Radioskop' | work = Memory of the World | publisher = [[UNESCO|United Nations Educational, Scientific and Cultural Organization (UNESCO)]] | url = http://portal.unesco.org/ci/en/ev.php-URL_ID=23240&URL_DO=DO_TOPIC&URL_SECTION=201.html| access-date =22 February 2008}}</ref><ref name=US2133123>United States Patent Office, Patent No. 2,133,123, 11 October 1938.</ref><ref name=US2158259>United States Patent Office, Patent No. 2,158,259, 16 May 1939</ref><ref>{{cite web|url=http://www.bairdtelevision.com/zworykin.html |title=Vladimir Kosma Zworykin, 1889\u20131982 |publisher=Bairdtelevision.com |access-date=17 April 2009}}</ref> The problem of low sensitivity to light resulting in low electrical output from transmitting or "camera" tubes would be solved with the introduction of charge-storage technology by K\u00e1lm\u00e1n Tihanyi beginning in 1924.<ref name="IEC_Tihanyi">[http://www.iec.ch/about/history/techline/swf/temp.xml] "K\u00e1lm\u00e1n Tihanyi (1897\u20131947)", ''IEC Techline'', International Electrotechnical Commission (IEC), 15 July 2009.</ref> His solution was a camera tube that accumulated and stored electrical charges ("photoelectrons") within the tube throughout each scanning cycle. The device was first described in a patent application he filed in [[Hungary]] in March 1926 for a television system he called "Radioskop".<ref name="Radioskop">[http://www.unesco.org/new/en/communication-and-information/flagship-project-activities/memory-of-the-world/register/full-list-of-registered-heritage/registered-heritage-page-4/kalman-tihanyis-1926-patent-application-radioskop/ "K\u00e1lm\u00e1n Tihanyi's 1926 Patent Application 'Radioskop'"], ''Memory of the World'', United Nations Educational, Scientific and Cultural Organization ([[UNESCO]]), 2005. Retrieved 29 January 2009.</ref> After further refinements included in a 1928 patent application,<ref name="IEC_Tihanyi"/> Tihanyi's patent was declared void in Great Britain in 1930,<ref name="abstract1928">[http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_V3&FT=D&date=19301111&CC=GB&NR=313456A&KC=A Tihanyi, Koloman, ''Improvements in television apparatus'']. European Patent Office, Patent No. GB313456. Convention date UK application: 1928-06-11, declared void and published: 11 November 1930. Retrieved 25 April 2013.</ref> so he applied for patents in the United States. Although his breakthrough would be incorporated into the design of [[RCA]]'s "[[iconoscope]]" in 1931, the U.S. patent for Tihanyi's transmitting tube would not be granted until May 1939. The patent for his receiving tube had been granted the previous October. Both patents had been purchased by RCA prior to their approval.<ref name=autogenerated1>{{cite web|url=https://www.google.com/patents?id=FD8BAAAAEBAJ&dq=2,133,123|title=Patent US2133123 \u2013 Television apparatus|access-date=22 March 2015}}</ref><ref name=autogenerated2>{{cite web|url=https://www.google.com/patents?id=lx1mAAAAEBAJ&dq=2,158,259|title=Patent US2158259 \u2013 Television apparatus|access-date=22 March 2015}}</ref> Charge storage remains a basic principle in the design of imaging devices for television to the present day.<ref name="Radioskop"/> On 25 December 1926, at Hamamatsu Industrial High School in Japan, Japanese inventor [[Kenjiro Takayanagi]] demonstrated a TV system with a 40-line resolution that employed a CRT display.<ref name="nhk.or.jp"/> This was the first working example of a fully electronic television receiver. Takayanagi did not apply for a patent.<ref>{{cite web|url=http://www.ieeeghn.org/wiki/index.php/Milestones:Development_of_Electronic_Television,_1924-1941|title=Milestones:Development of Electronic Television, 1924\u20131941|access-date=22 March 2015}}</ref>\n\nIn the 1930s, [[Allen B. DuMont]] made the first CRTs to last 1,000 hours of use, which was one of the factors that led to the widespread adoption of television.<ref>Hart, Hugh (28 January 2010). [https://www.wired.com/2010/01/jan-29-1901-dumont-will-make-tv-work-2/ "Jan. 29, 1901: DuMont Will Make TV Work."] ''[[Wired (magazine)|Wired]]''. Retrieved 21 May 2021.</ref>\n\nOn 7 September 1927, U.S. inventor [[Philo Farnsworth]]'s [[image dissector]] camera tube transmitted its first image, a simple straight line, at his laboratory at 202 Green Street in San Francisco.<ref name="Postman">[https://web.archive.org/web/20000531100005/http://www.time.com/time/time100/scientist/profile/farnsworth.html Postman, Neil, "Philo Farnsworth"], ''The TIME 100: Scientists & Thinkers'', ''Time'', 29 March 1999. Retrieved 28 July 2009.</ref><ref name="sfmuseum">[http://www.sfmuseum.org/hist10/philo.html "Philo Taylor Farnsworth (1906\u20131971)"] {{webarchive|url=https://web.archive.org/web/20110622033654/http://www.sfmuseum.org/hist10/philo.html |date=22 June 2011 }}, ''The Virtual Museum of the City of San Francisco''. Retrieved 15 July 2009.</ref> By 3 September 1928, Farnsworth had developed the system sufficiently to hold a demonstration for the press. This is widely regarded as the first electronic television demonstration.<ref name="sfmuseum"/> In 1929, the system was improved further by the elimination of a motor generator, so that his television system now had no mechanical parts.<ref>Abramson, Albert, ''Zworykin, Pioneer of Television'', p. 226.</ref> That year, Farnsworth transmitted the first live human images with his system, including a three and a half-inch image of his wife Elma ("Pem") with her eyes closed (possibly due to the bright lighting required).<ref>[https://web.archive.org/web/20080422211543/http://db3-sql.staff.library.utah.edu/lucene/Manuscripts/null/Ms0648.xml/complete The Philo T. and Elma G. Farnsworth Papers]</ref>\n\n[[File:Zworykin kinescope 1929.jpg|thumb|[[Vladimir Zworykin]] demonstrates electronic television (1929)]]\nMeanwhile, Vladimir Zworykin was also experimenting with the cathode ray tube to create and show images. While working for [[Westinghouse Electric (1886)|Westinghouse Electric]] in 1923, he began to develop an electronic camera tube. But in a 1925 demonstration, the image was dim, had low contrast, and poor definition, and was stationary.<ref>Abramson, Albert, ''Zworykin, Pioneer of Television'', University of Illinois Press, 1995, p. 51. {{ISBN|0-252-02104-5}}.</ref> Zworykin's imaging tube never got beyond the laboratory stage. But RCA, which acquired the Westinghouse patent, asserted that the patent for Farnsworth's 1927 image dissector was written so broadly that it would exclude any other electronic imaging device. Thus RCA, on the basis of Zworykin's 1923 patent application, filed a [[patent interference]] suit against Farnsworth. The [[United States Patent and Trademark Office|U.S. Patent Office]] examiner disagreed in a 1935 decision, finding priority of invention for Farnsworth against Zworykin. Farnsworth claimed that Zworykin's 1923 system would be unable to produce an electrical image of the type to challenge his patent. Zworykin received a patent in 1928 for a color transmission version of his 1923 patent application;<ref name=US1691324>[https://www.google.com/patents/about?id=mZ9KAAAAEBAJ Zworykin, Vladimir K., Television System] {{Webarchive|url=https://web.archive.org/web/20140131053220/http://www.google.com/patents/about?id=mZ9KAAAAEBAJ |date=31 January 2014 }}. Patent No. 1691324, U.S. Patent Office. Filed 1925-07-13, issued 13 November 1928. Retrieved 28 July 2009</ref> he also divided his original application in 1931.<ref name="US2022450">[https://www.google.com/patents?id=tQt-AAAAEBAJ Zworykin, Vladimir K., Television System] {{Webarchive|url=https://web.archive.org/web/20130518183522/http://www.google.com/patents?id=tQt-AAAAEBAJ |date=18 May 2013 }}. Patent No. 2022450, U.S. Patent Office. Filed 1923-12-29, issued 26 November 1935. Retrieved 10 May 2010.</ref> Zworykin was unable or unwilling to introduce evidence of a working model of his tube that was based on his 1923 patent application. In September 1939, after losing an appeal in the courts, and determined to go forward with the commercial manufacturing of television equipment, RCA agreed to pay Farnsworth US$1 million over a ten-year period, in addition to license payments, to use his patents.<ref>Stashower, Daniel, ''The Boy Genius and the Mogul: The Untold Story of Television'', Broadway Books, 2002, pp. 243\u201344. {{ISBN|978-0-7679-0759-0}}.</ref><ref name="Everson">Everson, George (1949), ''The Story of Television, The Life of Philo T. Farnsworth'' New York: W.W. Norton & Co,. {{ISBN|978-0-405-06042-7}}, 266 pp.</ref>\n\nIn 1933, RCA introduced an improved camera tube that relied on Tihanyi's charge storage principle.<ref name="NewYorkTimes">\n {{cite book\n | author=Lawrence, Williams L.\n | title=Human-like eye made by engineers to televise images. 'Iconoscope' converts scenes into electrical energy for radio transmission. Fast as a movie camera. Three million tiny photocells 'memorize', then pass out pictures. Step to home television. Developed in ten years' work by Dr. V.K. Zworykin, who describes it at Chicago.\n | url=https://books.google.com/books?id=OlXsZdT8HUQC&q=3971+zworykin+N.Y.T\n | date=27 June 1933\n| work=The New York Times\n | access-date=10 January 2010\n| isbn=978-0-8240-7782-2\n }}</ref> Called the "Iconoscope" by Zworykin, the new tube had a light sensitivity of about 75,000 [[lux]], and thus was claimed to be much more sensitive than Farnsworth's image dissector.{{Citation needed|date=July 2009}} However, Farnsworth had overcome his power issues with his Image Dissector through the invention of a completely unique "multipactor" device that he began work on in 1930, and demonstrated in 1931.<ref name="TheHistoryofTV1">Abramson, Albert (1987), ''The History of Television, 1880 to 1941''. Jefferson, NC: Albert Abramson. p. 148. {{ISBN|0-89950-284-9}}.</ref><ref name="Everson1">Everson, George (1949), ''The Story of Television, The Life of Philo T. Farnsworth'' New York: W.W. Norton & Co,. {{ISBN|978-0-405-06042-7}}, pp. 137\u201341.</ref> This small tube could amplify a signal reportedly to the 60th power or better<ref name="Everson2">Everson, George (1949), ''The Story of Television, The Life of Philo T. Farnsworth'' New York: W.W. Norton & Co,. {{ISBN|978-0-405-06042-7}}, p. 139.</ref> and showed great promise in all fields of electronics. Unfortunately, an issue with the multipactor was that it wore out at an unsatisfactory rate.<ref name="Everson3">Everson, George (1949), ''The Story of Television, The Life of Philo T. Farnsworth'' New York: W.W. Norton & Co,. {{ISBN|978-0-405-06042-7}}, p. 141.</ref>\n\nAt the [[Berlin Radio Show]] in August 1931, [[Manfred von Ardenne]] gave a public demonstration of a television system using a CRT for both transmission and reception. However, Ardenne had not developed a camera tube, using the CRT instead as a [[flying-spot scanner]] to scan slides and film.<ref>Albert Abramson, ''Zworykin: Pioneer of Television'', University of Illinois Press, 1995, p. 111.</ref> Philo Farnsworth gave the world's first public demonstration of an all-electronic television system, using a live camera, at the [[Franklin Institute]] of [[Philadelphia]] on 25 August 1934, and for ten days afterwards.<ref>"[https://books.google.com/books?id=yt8DAAAAMBAJ&pg=PA838 New Television System Uses 'Magnetic Lens']", ''Popular Mechanics'', Dec. 1934, pp. 838\u201339.</ref><ref name="Burns370">Burns, R.W. ''Television: An international history of the formative years''. (1998). IEE History of Technology Series, 22. London: IEE, p. 370. {{ISBN|9780852969144}}.</ref> Mexican inventor [[Guillermo Gonz\u00e1lez Camarena]] also played an important role in early television. His experiments with television (known as telectroescop\u00eda at first) began in 1931 and led to a patent for the "trichromatic field sequential system" [[color television]] in 1940.<ref>{{cite web|url=https://www.google.com/patents?id=sQBkAAAAEBAJ&dq=2296019|title=Patent US2296019 \u2013 Chromoscopic adapter for television equipment|access-date=22 March 2015}}</ref> In Britain, the [[EMI]] engineering team led by [[Isaac Shoenberg]] applied in 1932 for a patent for a new device they called "the Emitron",<ref name="GB406353">\n{{cite web\n |author1=EMI LTD |author2=Tedham, William F. |author3=McGee, James D. |name-list-style=amp | title = Improvements in or relating to cathode ray tubes and the like\n | url = http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_V3&FT=D&date=19340226&CC=GB&NR=406353A&KC=A\n | work = Patent No. GB 406,353 (filed May 1932, patented 1934)\n | publisher = United Kingdom Intellectual Property Office\n | access-date = 22 February 2010\n}}</ref><ref name="US2077442">\n{{cite web\n |author1=Tedham, William F. |author2=McGee, James D.\n |name-list-style=amp | title=Cathode Ray Tube\n | url=https://www.google.com/patents/about?id=BYNaAAAAEBAJ\n | work=Patent No. 2,077,422 (filed in Great Britain 1932, filed in USA 1933, patented 1937)\n | publisher=United States Patent Office\n | access-date=10 January 2010\n}}</ref> which formed the heart of the cameras they designed for the BBC. On 2 November 1936, a [[405-line television system|405-line broadcasting]] service employing the Emitron began at studios in [[Alexandra Palace]], and transmitted from a specially built mast atop one of the Victorian building's towers. It alternated for a short time with Baird's mechanical system in adjoining studios, but was more reliable and visibly superior. This was the world's first regular "high-definition" television service.<ref name="Burns576">Burns, R.W., ''Television: An international history of the formative years''. (1998). IEE History of Technology Series, 22. London: IEE, p. 576. {{ISBN|0-85296-914-7}}.</ref>\n\nThe original U.S. iconoscope was noisy, had a high ratio of interference to signal, and ultimately gave disappointing results, especially when compared to the high definition mechanical scanning systems then becoming available.<ref name="Winstor-media">{{cite book\n| title = Misunderstanding media\n| author = Winston, Brian\n| publisher = Harvard University Press\n| year = 1986\n| isbn = 978-0-674-57663-6\n| pages = 60\u201361\n| url = https://books.google.com/books?id=K_RpAAAAIAAJ&q=%22american+iconoscope%22+noisy\n| access-date = 9 March 2010\n}}</ref><ref name="Winstor-history">{{cite book\n| title = Media technology and society. A history: from the telegraph to the Internet\n| author = Winston, Brian\n| publisher = Routledge\n| year = 1998\n| isbn = 978-0-415-14230-4\n| page = 105\n| url = https://books.google.com/books?id=TZOF_1GZRmYC&q=american+iconoscope+noisy\n| access-date = 9 March 2010\n}}</ref> The [[EMI]] team, under the supervision of [[Isaac Shoenberg]], analyzed how the iconoscope (or Emitron) produces an electronic signal and concluded that its real efficiency was only about 5% of the theoretical maximum.<ref name="Alexander">\n{{cite book\n| title=The inventor of stereo: the life and works of Alan Dower Blumlein\n| author=Alexander, Robert Charles\n| publisher=Focal Press\n| year=2000\n| isbn=978-0-240-51628-8\n| pages=217\u201319\n| url=https://books.google.com/books?id=qRhx3UmYBz0C&q=super+emitron\n| access-date=10 January 2010\n}}</ref><ref name="Burns-Blumlein">\n{{cite book\n| title=The life and times of A.D. Blumlein\n| author=Burns, R.W.\n| publisher=IET\n| year=2000\n| isbn=978-0-85296-773-7\n| page=181\n| url=https://books.google.com/books?id=B2z2ONO7nBQC&q=blumlein+mcgee+cps+emitron+decelerating+zero\n| access-date=5 March 2010\n}}</ref> They solved this problem by developing, and patenting in 1934, two new camera tubes dubbed [[Video camera tube#Super-Emitron and image iconoscope|super-Emitron]] and [[Video camera tube#Orthicon and CPS Emitron|CPS Emitron]].<ref name="GB442666">\n{{cite web\n |author1=Lubszynski, Hans Gerhard |author2=Rodda, Sydney\n |name-list-style=amp | title = Improvements in or relating to television\n | url = http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_V3&FT=D&date=19360212&CC=GB&NR=442666A&KC=A\n | work = Patent No. GB 442,666 (filed May 1934, patented 1936)\n | publisher = United Kingdom Intellectual Property Office\n | access-date = 15 January 2010\n}}</ref><ref name="GB446661">\n{{cite web\n |author1=Blumlein, Alan Dower |author2=McGee, James Dwyer\n |name-list-style=amp | title = Improvements in or relating to television transmitting systems\n | url = http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_V3&FT=D&date=19360504&CC=GB&NR=446661A&KC=A\n | work = Patent No. GB 446,661 (filed August 1934, patented 1936)\n | publisher = United Kingdom Intellectual Property Office\n | access-date = 9 March 2010\n}}</ref><ref name="GB446664">\n{{cite web\n | author = McGee, James Dwyer\n | title = Improvements in or relating to television transmitting systems\n | url = http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_V3&FT=D&date=19360505&CC=GB&NR=446664A&KC=A\n | work = Patent No. GB 446,664 (filed September 1934, patented 1936)\n | publisher = United Kingdom Intellectual Property Office\n | access-date = 9 March 2010\n}}</ref> The super-Emitron was between ten and fifteen times more sensitive than the original Emitron and iconoscope tubes and, in some cases, this ratio was considerably greater.<ref name="Alexander"/> It was used for [[outside broadcasting]] by the BBC, for the first time, on [[Armistice Day]] 1937, when the general public could watch on a television set as the King laid a wreath at the Cenotaph.<ref name="Alexander2">\n{{cite book\n| title=The inventor of stereo: the life and works of Alan Dower Blumlein\n| author=Alexander, Robert Charles\n| publisher=Focal Press\n| year=2000\n| isbn=978-0-240-51628-8\n| page=216\n| url=https://books.google.com/books?id=qRhx3UmYBz0C&q=emitron+cenotaph+armistice\n| access-date=10 January 2010\n}}</ref> This was the first time that anyone had broadcast a live street scene from cameras installed on the roof of neighboring buildings, because neither Farnsworth nor RCA would do the same until the [[1939 New York World's Fair]].\n[[File:1939 RCA Television Advertisement.jpg|left|thumb|Ad for the beginning of experimental television broadcasting in New York City by RCA in 1939]]\n[[File:RCA Indian Head test pattern.JPG|thumb|right|[[Indian-head test pattern]] used during the black-and-white era before 1970. It was displayed when a television station first signed on every day.]]\nOn the other hand, in 1934, Zworykin shared some patent rights with the German licensee company Telefunken.<ref name="Inglis">{{cite book\n | title = Behind the tube: a history of broadcasting technology and business\n | author = Inglis, Andrew F.\n | publisher = Focal Press\n | year = 1990\n | isbn = 978-0-240-80043-1\n | page = 172\n | url = https://books.google.com/books?id=xiu4AAAAIAAJ&q=image-iconoscope+telefunken\n | access-date = 15 January 2010\n}}</ref> The "image iconoscope" ("Superikonoskop" in Germany) was produced as a result of the collaboration. This tube is essentially identical to the super-Emitron.{{Citation needed|date=May 2010}} The production and commercialization of the super-Emitron and image iconoscope in Europe were not affected by the [[patent war]] between Zworykin and Farnsworth, because Dieckmann and Hell had priority in Germany for the invention of the image dissector, having submitted a patent application for their ''Lichtelektrische Bildzerlegerr\u00f6hre f\u00fcr Fernseher'' (''Photoelectric Image Dissector Tube for Television'') in Germany in 1925,<ref name="DE450187">\n{{cite web\n |author1=Dieckmann, Max |author2=Rudolf Hell\n |name-list-style=amp | title = Lichtelektrische Bildzerlegerr\u00f6ehre f\u00fcr Fernseher\n | url = http://v3.espacenet.com/publicationDetails/originalDocument?CC=DE&NR=450187C&KC=C&FT=D&date=19271003&DB=EPODOC&locale=en_V3\n | work = Patent No. DE 450,187 (filed 1925, patented 1927)\n | publisher = Deutsches Reich Reichspatentamt\n | access-date = 28 July 2009\n}}</ref> two years before Farnsworth did the same in the United States.<ref name="US1773980">\n{{cite web\n | author = Farnsworth, Philo T.\n | title = Television System\n | url=https://www.google.com/patents/about?id=HRd5AAAAEBAJ\n | work = Patent No. 1,773,980 (filed 1927, patented 1930)\n | publisher = United States Patent Office\n | access-date = 28 July 2009\n}}</ref> The image iconoscope (Superikonoskop) became the industrial standard for public broadcasting in Europe from 1936 until 1960, when it was replaced by the [[Video camera tube|vidicon]] and [[Video camera tube|plumbicon]] tubes. Indeed, it was the representative of the European tradition in electronic tubes competing against the American tradition represented by the image orthicon.<ref name="Vries">{{cite book\n | title = Design methodology and relationships with science, N\u00famero 71 de NATO ASI series\n |author1=de Vries, M.J. |author2=de Vries, Marc |author3=Cross, Nigel |author4=Grant, Donald P. |name-list-style=amp | publisher = Springer\n | year = 1993\n | isbn = 978-0-7923-2191-0\n | page = 222\n | url = https://books.google.com/books?id=4T8U_J1h7noC&q=image-iconoscope+image-orthicon+telefunken\n | access-date = 15 January 2010\n}}</ref><ref name="Multicon">\n{{cite web\n | author = Smith, Harry\n | title = Multicon \u2013 A new TV camera tube\n | url = http://www.earlytelevision.org/multicon.html\n | archive-url = https://web.archive.org/web/20100318011743/http://www.earlytelevision.org/multicon.html\n | archive-date = 18 March 2010\n| work = newspaper article\n | date = July 1953\n | publisher = Early Television Foundation and Museum\n | access-date = 15 January 2010\n}}</ref> The German company Heimann produced the Superikonoskop for the 1936 Berlin Olympic Games,<ref name="Heimann1">\n{{cite web\n| author=Gittel, Joachim\n| title=Spezialr\u00f6hren\n| url=http://www.jogis-roehrenbude.de/Roehren-Geschichtliches/Spezialroehren/Spezialroehren.htm\n| work=photographic album\n| date=11 October 2008\n| publisher=Jogis R\u00f6hrenbude\n| access-date=15 January 2010\n}}</ref><ref name="ETM">\n{{cite web\n | author = Early Television Museum\n | title = TV Camera Tubes, German "Super Iconoscope" (1936)\n | url = http://www.earlytelevision.org/prewar_camera_tubes.html\n | archive-url = https://web.archive.org/web/20110617080126/http://www.earlytelevision.org/prewar_camera_tubes.html\n | archive-date = 17 June 2011\n| work = photographic album\n | publisher = Early Television Foundation and Museum\n | access-date = 15 January 2010\n}}</ref> later Heimann also produced and commercialized it from 1940 to 1955;<ref name="Heimann2">\n{{cite web\n| author=Gittel, Joachim\n| title=FAR-R\u00f6hren der Firma Heimann\n| url=http://www.jogis-roehrenbude.de/Roehren-Geschichtliches/Spezialroehren/Ikonoskop_Heimann/Heimann.htm\n| work=photographic album\n| date=11 October 2008\n| publisher=Jogis R\u00f6hrenbude\n| access-date=15 January 2010\n}}</ref> finally the Dutch company [[Philips]] produced and commercialized the image iconoscope and multicon from 1952 to 1958.<ref name="Multicon"/><ref name="Philips">\n{{cite web\n | author = Philips\n | title = 5854, Image Iconoscope, Philips\n | url = http://www.jogis-roehrenbude.de/Roehren-Geschichtliches/Spezialroehren/Ikonoskop_Heimann/5854_Philips_Iconoscop-1958.pdf\n | work = electronic tube handbook\n | year = 1958\n | publisher = Philips\n | access-date = 15 January 2010\n}}</ref>\n\nU.S. television broadcasting, at the time, consisted of a variety of markets in a wide range of sizes, each competing for programming and dominance with separate technology, until deals were made and standards agreed upon in 1941.<ref name="Everson4">Everson, George (1949), ''The Story of Television, The Life of Philo T. Farnsworth'' New York: W.W. Norton & Co,. {{ISBN|978-0-405-06042-7}}, p. 248.</ref> RCA, for example, used only Iconoscopes in the New York area, but Farnsworth Image Dissectors in Philadelphia and San Francisco.<ref name="TheHistoryofTV2">Abramson, Albert (1987), ''The History of Television, 1880 to 1941''. Jefferson, NC: Albert Abramson. p. 254. {{ISBN|0-89950-284-9}}.</ref> In September 1939, RCA agreed to pay the Farnsworth Television and Radio Corporation royalties over the next ten years for access to Farnsworth's patents.<ref name="Schatzkin187-8">Schatzkin, Paul (2002), ''The Boy Who Invented Television''. Silver Spring, Maryland: Teamcom Books, pp. 187\u201388. {{ISBN|1-928791-30-1}}.</ref> With this historic agreement in place, RCA integrated much of what was best about the Farnsworth Technology into their systems.<ref name="TheHistoryofTV2"/> In 1941, the United States implemented 525-line television.<ref>"Go-Ahead Signal Due for Television", ''The New York Times'', 25 April 1941, p. 7.</ref><ref>"An Auspicious Beginning", ''The New York Times'', 3 August 1941, p. X10.</ref> Electrical engineer [[Benjamin Adler]] played a prominent role in the development of television.<ref>{{cite web|url=https://www.nytimes.com/1990/04/18/obituaries/benjamin-adler-86-an-early-advocate-of-uhf-television.html|title=Benjamin Adler, 86, An Early Advocate of UHF Television|date=18 April 1990|work=The New York Times}}</ref><ref>{{cite web|url=http://archive.poly.edu/poly_ebriefs/archives/Feb03.htm|title=ePoly Briefs Home}}</ref>\n\nThe world's first 625-line television standard was designed in the Soviet Union in 1944 and became a national standard in 1946.<ref name="60TH_ANNIVERSARY_OF_625">[http://625.625-net.ru/files/587/511/h_665921be9883776271895912fb8bb262 "On the beginning of broadcast in 625 lines 60 years ago"], ''625'' magazine (in Russian). {{webarchive|url=https://web.archive.org/web/20160304131236/http://625.625-net.ru/files/587/511/h_665921be9883776271895912fb8bb262 |date=4 March 2016 }}</ref> The first broadcast in 625-line standard occurred in Moscow in 1948.<ref>[https://web.archive.org/web/20041230091501/http://www.ebu.ch/en/technical/trev/trev_255-portrait.pdf "M.I. Krivocheev \u2013 an engineer's engineer"], ''EBU Technical Review'', Spring 1993.</ref> The concept of 625 lines per frame was subsequently implemented in the European [[Comit\u00e9 consultatif international pour la radio|CCIR]] standard.<ref>[https://web.archive.org/web/20070221210300/http://cra.ir/FTD/Static/RRC/RRCFile10.pdf "In the Vanguard of Television Broadcasting".]</ref> In 1936, [[K\u00e1lm\u00e1n Tihanyi]] described the principle of [[plasma display]], the first [[flat panel display]] system.<ref>[http://ewh.ieee.org/r2/johnstown/downloads/20090217_IEEE_JST_Trivia_Answers.pdf ] {{webarchive |url=https://web.archive.org/web/20130807220013/http://ewh.ieee.org/r2/johnstown/downloads/20090217_IEEE_JST_Trivia_Answers.pdf |date=7 August 2013 }}</ref><ref>[http://www.scitech.mtesz.hu/52tihanyi/flat-panel_tv_en.pdf] {{webarchive |url=https://web.archive.org/web/20120314070853/http://www.scitech.mtesz.hu/52tihanyi/flat-panel_tv_en.pdf |date=14 March 2012 }}</ref>\n\nEarly electronic [[television sets]] were large and bulky, with [[analog circuits]] made of [[vacuum tubes]]. Following the invention of the first working [[transistor]] at [[Bell Labs]], [[Sony]] founder [[Masaru Ibuka]] predicted in 1952 that the transition to [[electronic circuits]] made of transistors would lead to smaller and more portable television sets.<ref>{{cite book |last1=Childs |first1=William R. |last2=Martin |first2=Scott B. |last3=Stitt-Gohdes |first3=Wanda |title=Business and Industry: Savings and investment options to telecommuting |date=2004 |publisher=[[Marshall Cavendish]] |isbn=9780761474395 |page=1217 |url=https://books.google.com/books?id=nCwYAAAAIAAJ |quote=In 1952 Ibuka toured AT&T's Bell Laboratories in the United States and saw the newly invented transistor. He realized that replacing the large, clumsy vacuum tube with the transistor would make possible smaller, more portable radios and TVs.}}</ref> The first fully transistorized, portable [[solid-state electronics|solid-state]] television set was the 8-inch [[Sony TV8-301]], developed in 1959 and released in 1960.<ref>{{cite journal |title=Sony Founder Masaru Ibuka's New Year's Dream Comes True: The Launch of Sony's TV Business |journal=Time Capsule |date=17 November 2009 |volume=21 |publisher=[[Sony]] |url=https://www.sony.net/SonyInfo/CorporateInfo/History/capsule/21/index.html |access-date=1 October 2019}}</ref><ref>{{cite book |last1=Sparke |first1=Penny |title=Japanese Design |date=2009 |publisher=[[The Museum of Modern Art]] |isbn=9780870707391 |page=18 |url=https://books.google.com/books?id=WaIQf2gV8pEC&pg=PA18}}</ref> This began the transformation of television viewership from a communal viewing experience to a solitary viewing experience.<ref>{{cite book |last1=Lucie-Smith |first1=Edward |title=A History of Industrial Design |date=1983 |publisher=[[Phaidon Press]] |isbn=9780714822815 |page=208 |url=https://books.google.com/books?id=fMsfAQAAIAAJ |quote=The first all-transistor television set was introduced by Sony in 1959 (fig. 386), only four years after their all-transistor radio, and started the transformation of television from something used for communal viewing, as the radio in the 30s had been a focus for communal listening, into an object of solitary contemplation.}}</ref> By 1960, Sony had sold over 4{{nbsp}}million portable television sets worldwide.<ref>{{cite book |last1=Chang |first1=Yoon Seok |last2=Makatsoris |first2=Harris C. |last3=Richards |first3=Howard D. |title=Evolution of Supply Chain Management: Symbiosis of Adaptive Value Networks and ICT |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9780306486968 |url=https://books.google.com/books?id=5Y3wBwAAQBAJ&pg=PA48 |language=en}}</ref>\n{{Clear}}\n\n {{Main|Color television}}\n[[File:Samsung LED TV.jpg|thumb|right|Samsung LED TV]]\nThe basic idea of using three monochrome images to produce a color image had been experimented with almost as soon as black-and-white televisions had first been built. Although he gave no practical details, among the earliest published proposals for television was one by Maurice Le Blanc, in 1880, for a color system, including the first mentions in television literature of line and frame scanning.<ref>M. Le Blanc, "Etude sur la transmission \u00e9lectrique des impressions lumineuses", ''La Lumi\u00e8re Electrique'', vol. 11, 1 December 1880, pp. 477\u201381.</ref> Polish inventor [[Jan Szczepanik]] patented a color television system in 1897, using a [[selenium]] photoelectric cell at the transmitter and an electromagnet controlling an oscillating mirror and a moving prism at the receiver. But his system contained no means of analyzing the spectrum of colors at the transmitting end, and could not have worked as he described it.<ref>R.W. Burns, ''Television: An International History of the Formative Years'', IET, 1998, p. 98. {{ISBN|0-85296-914-7}}.</ref> Another inventor, [[Hovannes Adamian]], also experimented with color television as early as 1907. The first color television project is claimed by him,<ref>Western technology and Soviet economic development: 1945 to 1965, by Antony C. Sutton, Business & Economics \u2013 1973, p. 330</ref> and was patented in Germany on 31 March 1908, patent No. 197183, then in Britain, on 1 April 1908, patent No. 7219,<ref>The History of Television, 1880\u20131941, by Albert Abramson, 1987, p. 27</ref> in France (patent No. 390326) and in Russia in 1910 (patent No. 17912).<ref name="tvmuseum.ru">[http://www.tvmuseum.ru/attach.asp?a_no=1018 A. Rokhlin, Tak rozhdalos' dal'novidenie (in Russian)] {{webarchive|url=https://web.archive.org/web/20130424162531/http://www.tvmuseum.ru/attach.asp?a_no=1018 |date=24 April 2013 }}</ref>\n\nScottish inventor [[John Logie Baird]] demonstrated the world's first color transmission on 3 July 1928, using scanning discs at the transmitting and receiving ends with three spirals of apertures, each spiral with filters of a different primary color; and three light sources at the receiving end, with a [[commutator (electric)|commutator]] to alternate their illumination.<ref>John Logie Baird, [https://www.google.com/patents?id=JRVAAAAAEBAJ Television Apparatus and the Like], U.S. patent, filed in U.K. in 1928.</ref> Baird also made the world's first color broadcast on 4 February 1938, sending a mechanically scanned 120-line image from Baird's [[The Crystal Palace|Crystal Palace]] studios to a projection screen at London's [[Dominion Theatre]].<ref>Baird Television: [http://www.bairdtelevision.com/crystalpalace.html Crystal Palace Television Studios]. Previous color television demonstrations in the U.K. and U.S. had been via closed circuit.</ref> Mechanically scanned color television was also demonstrated by [[Bell Laboratories]] in June 1929 using three complete systems of [[Solar cell|photoelectric cells]], amplifiers, glow-tubes, and color filters, with a series of mirrors to superimpose the red, green, and blue images into one full color image.\n\nThe first practical hybrid system was again pioneered by John Logie Baird. In 1940 he publicly demonstrated a color television combining a traditional black-and-white display with a rotating colored disk. This device was very "deep", but was later improved with a mirror folding the light path into an entirely practical device resembling a large conventional console.<ref>{{cite web|url=http://www.bairdtelevision.com/colour.html|title=The World's First High Definition Colour Television System|access-date=22 March 2015}}</ref> However, Baird was unhappy with the design, and, as early as 1944, had commented to a British government committee that a fully electronic device would be better.\n\nIn 1939, Hungarian engineer [[Peter Carl Goldmark]] introduced an electro-mechanical system while at [[CBS]], which contained an [[Iconoscope]] sensor. The CBS field-sequential color system was partly mechanical, with a disc made of red, blue, and green filters spinning inside the television camera at 1,200 rpm, and a similar disc spinning in synchronization in front of the cathode ray tube inside the receiver set.<ref>Peter C. Goldmark, assignor to Columbia Broadcasting System, "Color Television", [https://www.google.com/patents?id=7pNDAAAAEBAJ&dq=color+television&as_drrb_ap=b&as_minm_ap=1&as_miny_ap=1936&as_maxm_ap=12&as_maxy_ap=1941&as_drrb_is=q&as_minm_is=1&as_miny_is=2007&as_maxm_is=1&as_maxy_is=2007 U.S. Patent 2,480,571], filed 7 September 1940.</ref> The system was first demonstrated to the [[Federal Communications Commission]] (FCC) on 29 August 1940, and shown to the press on 4 September.<ref>Current Broadcasting 1940</ref><ref name=ColorTVSuccess>"Color Television Success in Test", ''The New York Times'', 30 August 1940, p. 21.</ref><ref>"Color Television Achieves Realism", ''The New York Times'', 5 September 1940, p. 18.</ref><ref>"[https://books.google.com/books?id=JScDAAAAMBAJ&pg=PA120 New Television System Transmits Images in Full Color]", ''Popular Science'', December 1940, p. 120.</ref>\n\nCBS began experimental color field tests using film as early as August 28, 1940, and live cameras by 12 November.<ref name="ColorTVSuccess" /><ref>"CBS Demonstrates Full Color Television," ''The Wall Street Journal'', 5 September 1940, p. 1. "Television Hearing Set," ''The New York Times'', 13 November 1940, p. 26.</ref> [[NBC]] (owned by RCA) made its first field test of color television on February 20, 1941. CBS began daily color field tests on June 1, 1941.<ref>Ed Reitan, [http://colortelevision.info/rca-nbc_firsts.html RCA-NBC Color Firsts in Television (commented)].</ref> These color systems were not compatible with existing black-and-white [[television sets]], and, as no color television sets were available to the public at this time, viewing of the color field tests was restricted to RCA and CBS engineers and the invited press. The [[War Production Board]] halted the manufacture of television and radio equipment for civilian use from April 22, 1942, to 20 August 1945, limiting any opportunity to introduce color television to the general public.<ref>"Making of Radios and Phonographs to End April 22," ''The New York Times'', 8 March 1942, p. 1. "Radio Production Curbs Cover All Combinations," ''The Wall Street Journal'', 3 June 1942, p. 4. "WPB Cancels 210 Controls; Radios, Trucks in Full Output," ''New York Times'', 21 August 1945, p. 1.</ref><ref>Bob Cooper, "[http://www.earlytelevision.org/color_tv_cooper.html Television: The Technology That Changed Our Lives]", Early Television Foundation.</ref>\n\nAs early as 1940, Baird had started work on a fully electronic system he called [[Telechrome]]. Early Telechrome devices used two electron guns aimed at either side of a phosphor plate. The phosphor was patterned so the electrons from the guns only fell on one side of the patterning or the other. Using cyan and magenta phosphors, a reasonable limited-color image could be obtained. He also demonstrated the same system using monochrome signals to produce a 3D image (called "[[Stereoscopy|stereoscopic]]" at the time). A demonstration on 16 August 1944 was the first example of a practical color television system. Work on the Telechrome continued and plans were made to introduce a three-gun version for full color. However, Baird's untimely death in 1946 ended development of the Telechrome system.<ref>Albert Abramson, ''The History of Television, 1942 to 2000'', McFarland & Company, 2003, pp. 13\u201314. {{ISBN|0-7864-1220-8}}</ref><ref>Baird Television: [http://www.bairdtelevision.com/colour.html The World's First High Definition Colour Television System].</ref>\nSimilar concepts were common through the 1940s and 1950s, differing primarily in the way they re-combined the colors generated by the three guns. The [[Geer tube]] was similar to Baird's concept, but used small pyramids with the phosphors deposited on their outside faces, instead of Baird's 3D patterning on a flat surface. The [[Penetron]] used three layers of phosphor on top of each other and increased the power of the beam to reach the upper layers when drawing those colors. The [[Chromatron]] used a set of focusing wires to select the colored phosphors arranged in vertical stripes on the tube.\n\nOne of the great technical challenges of introducing color [[broadcast television]] was the desire to conserve [[bandwidth (signal processing)|bandwidth]], potentially three times that of the existing [[black-and-white]] standards, and not use an excessive amount of [[radio spectrum]]. In the United States, after considerable research, the [[NTSC|National Television Systems Committee]]<ref name=name>National Television System Committee (1951\u20131953), [Report and Reports of Panel No. 11, 11-A, 12\u201319, with Some supplementary references cited in the Reports, and the Petition for adoption of transmission standards for color television before the Federal Communications Commission, n.p., 1953], 17 v. illus., diagrams., tables. 28 cm. LC Control No.:54021386 [http://catalog.loc.gov/cgi-bin/Pwebrecon.cgi?DB=local&PAGE=First Library of Congress Online Catalog]</ref> approved an all-electronic system developed by [[RCA]], which encoded the color information separately from the brightness information and greatly reduced the resolution of the color information in order to conserve bandwidth. As black-and-white televisions could receive the same transmission and display it in black-and-white, the color system adopted is [backwards] "compatible". ("Compatible Color", featured in RCA advertisements of the period, is mentioned in the song "[[America (West Side Story song)|America]]", of [[West Side Story]], 1957.) The brightness image remained compatible with existing black-and-white television sets at slightly reduced resolution, while color televisions could decode the extra information in the signal and produce a limited-resolution color display. The higher resolution black-and-white and lower resolution color images combine in the brain to produce a seemingly high-resolution color image. The NTSC standard represented a major technical achievement.\n\n[[File:SMPTE Color Bars.svg|thumb|left|Color bars used in a [[test pattern]], sometimes used when no program material is available.]]\nThe first color broadcast (the first episode of the live program ''[[The Marriage (TV series)|The Marriage]]'') occurred on 8 July 1954, but during the following ten years most network broadcasts, and nearly all local programming, continued to be in black-and-white. It was not until the mid-1960s that color sets started selling in large numbers, due in part to the color transition of 1965 in which it was announced that over half of all network prime-time programming would be broadcast in color that fall. The first all-color prime-time season came just one year later. In 1972, the last holdout among daytime network programs converted to color, resulting in the first completely all-color network season.\n\nEarly color sets were either floor-standing console models or tabletop versions nearly as bulky and heavy, so in practice they remained firmly anchored in one place. [[General Electric|GE]]'s relatively compact and lightweight [[Porta-Color]] set was introduced in the spring of 1966. It used a [[transistor]]-based [[UHF television broadcasting|UHF tuner]].<ref>{{cite web |title=GE Portacolor |url=http://www.earlytelevision.org/ge_portacolor.html |website=[[Early Television Museum]] |access-date=2 October 2019}}</ref> The first fully transistorized color television in the United States was the [[Quasar (brand)|Quasar]] television introduced in 1967.<ref>{{cite book |last1=Tyson |first1=Kirk |title=Competition in the 21st Century |date=1996 |publisher=[[CRC Press]] |isbn=9781574440324 |page=[https://archive.org/details/competitionin21s00tyso/page/253 253] |url=https://archive.org/details/competitionin21s00tyso|url-access=registration }}</ref> These developments made watching color television a more flexible and convenient proposition.\n\nThe [[MOSFET]] (metal-oxide-semiconductor field-effect transistor, or MOS transistor) was invented by [[Mohamed M. Atalla]] and [[Dawon Kahng]] at [[Bell Labs]] in 1959,<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960 - Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]]|access-date=29 July 2019}}</ref> and presented in 1960.<ref>{{cite journal |last1=Atalla |first1=M. |author1-link=Mohamed Atalla |last2=Kahng |first2=D. |author2-link=Dawon Kahng |title=Silicon-silicon dioxide field induced surface devices |journal=IRE-AIEE Solid State Device Research Conference |date=1960}}</ref> By the mid-1960s, [[RCA]] were using MOSFETs in their consumer television products.<ref name="Harrison">{{cite book |last1=Harrison |first1=Linden T. |title=Current Sources and Voltage References: A Design Reference for Electronics Engineers |date=2005 |publisher=Elsevier |isbn=978-0-08-045555-6 |page=185 |url=https://books.google.com/books?id=03JmxpE39N4C&pg=PA185}}</ref> [[RCA Laboratories]] researchers W.M. Austin, J.A. Dean, D.M. Griswold and O.P. Hart in 1966 described the use of the MOSFET in television circuits, including [[RF amplifier]], low-level video, [[chrominance|chroma]] and [[Automatic gain control|AGC]] circuits.<ref>{{cite journal |last1=Austin |first1=W. M. |last2=Dean |first2=J. A. |last3=Griswold |first3=D. M. |last4=Hart |first4=O. P. |title=TV Applications of MOS Transistors |journal=IEEE Transactions on Broadcast and Television Receivers |date=November 1966 |volume=12 |issue=4 |pages=68\u201376 |doi=10.1109/TBTR1.1966.4320029}}</ref> The [[power MOSFET]] was later widely adopted for [[television receiver]] circuits.<ref>{{cite book |last1=Amos |first1=S. W. |last2=James |first2=Mike |title=Principles of Transistor Circuits: Introduction to the Design of Amplifiers, Receivers and Digital Circuits |date=2013 |publisher=[[Elsevier]] |isbn=9781483293905 |page=332 |url=https://books.google.com/books?id=11EvBQAAQBAJ&pg=PA332}}</ref>\n\nIn 1972, sales of color sets finally surpassed sales of black-and-white sets. Color broadcasting in Europe was not standardized on the [[PAL]] format until the 1960s, and broadcasts did not start until 1967. By this point many of the technical issues in the early sets had been worked out, and the spread of color sets in Europe was fairly rapid. By the mid-1970s, the only stations broadcasting in black-and-white were a few high-numbered UHF stations in small markets, and a handful of low-power repeater stations in even smaller markets such as vacation spots. By 1979, even the last of these had converted to color and, by the early 1980s, B&W sets had been pushed into niche markets, notably low-power uses, small portable sets, or for use as [[video monitor]] screens in lower-cost consumer equipment. By the late 1980s even these areas switched to color sets.\n\n {{main|Digital television}}\n{{see also|Digital television transition}}\n\nDigital television (DTV) is the transmission of audio and video by digitally processed and multiplexed signals, in contrast to the totally analog and channel separated signals used by [[analog television]]. Due to [[data compression]], digital television can support more than one program in the same channel bandwidth.<ref>{{cite web | url=http://www.disabled-world.com/artman/publish/digital-hdtv.shtml | title=HDTV Set Top Boxes and Digital TV Broadcast Information | access-date=28 June 2014 | url-status=dead | archive-url=http://arquivo.pt/wayback/20160522191336/http://www.disabled%2Dworld.com/artman/publish/digital%2Dhdtv.shtml | archive-date=22 May 2016 | df=dmy-all }}</ref> It is an innovative service that represents the most significant evolution in television broadcast technology since color television emerged in the 1950s.<ref>{{cite book |last1=Kruger |first1=Lennard G. |last2=Guerrero |first2=Peter F. |title=Digital Television: An Overview |date=2002 |publisher=[[Nova Publishers]] |isbn=9781590335024 |page=1 |url=https://books.google.com/books?id=BIAfWq2V3wgC&pg=PA1 |location=Hauppauge, New York}}</ref> Digital television's roots have been tied very closely to the availability of inexpensive, high performance [[computers]]. It was not until the 1990s that digital television became possible.<ref>{{cite web|url=http://www.benton.org/initiatives/obligations/charting_the_digital_broadcasting_future/sec1|title=The Origins and Future Prospects of Digital Television|date=22 December 2008|access-date=22 March 2015}}</ref> Digital television was previously not practically possible due to the impractically high [[Bandwidth (computing)|bandwidth]] requirements of [[uncompressed video|uncompressed]] [[digital video]],<ref name="Lea">{{cite book |last1=Lea |first1=William |title=Video on demand: Research Paper 94/68 |date=1994 |publisher=[[House of Commons Library]] |location=9 May 1994 |url=https://researchbriefings.parliament.uk/ResearchBriefing/Summary/RP94-68 |access-date=20 September 2019}}</ref><ref name="Barbero">{{cite journal |last1=Barbero |first1=M. |last2=Hofmann |first2=H. |last3=Wells |first3=N. D. |title=DCT source coding and current implementations for HDTV |journal=EBU Technical Review |date=14 November 1991 |issue=251 |pages=22\u201333 |publisher=[[European Broadcasting Union]] |url=https://tech.ebu.ch/publications/trev_251-barbero |access-date=4 November 2019}}</ref> requiring around 200{{nbsp}}[[Mbit/s]] for a [[standard-definition television]] (SDTV) signal,<ref name="Lea"/> and over 1{{nbsp}}[[Gbit/s]] for [[high-definition television]] (HDTV).<ref name="Barbero"/>\n\nDigital television became practically possible in the early 1990s due to a major technological development, [[discrete cosine transform]] (DCT) [[video compression]].<ref name="Lea"/><ref name="Barbero"/> DCT coding is a [[lossy compression]] technique that was first proposed for [[image compression]] by [[N. Ahmed|Nasir Ahmed]] in 1972,<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I Came Up With the Discrete Cosine Transform |journal=[[Digital Signal Processing (journal)|Digital Signal Processing]] |date=January 1991 |volume=1 |issue=1 |pages=4\u20135 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform}}</ref> and was later adapted into a [[Motion compensation|motion-compensated]] DCT video coding algorithm, for [[video coding standards]] such as the [[H.26x]] formats from 1988 onwards and the [[MPEG]] formats from 1991 onwards.<ref name="Ghanbari">{{cite book |last1=Ghanbari |first1=Mohammed |title=Standard Codecs: Image Compression to Advanced Video Coding |date=2003 |publisher=[[Institution of Engineering and Technology]] |isbn=9780852967102 |pages=1\u20132 |url=https://books.google.com/books?id=7XuU8T3ooOAC&pg=PA1}}</ref><ref name="Li">{{cite book |last1=Li |first1=Jian Ping |title=Proceedings of the International Computer Conference 2006 on Wavelet Active Media Technology and Information Processing: Chongqing, China, 29-31 August 2006 |date=2006 |publisher=[[World Scientific]] |isbn=9789812709998 |page=847 |url=https://books.google.com/books?id=FZiK3zXdK7sC&pg=PA847}}</ref> Motion-compensated DCT video compression significantly reduced the amount of bandwidth required for a digital television signal.<ref name="Lea"/><ref name="Barbero"/> DCT coding compressed down the bandwidth requirements of digital television signals to about 34{{nbsp}} Mbit/s for SDTV and around 70{{ndash}}140 Mbit/s for HDTV while maintaining near-studio-quality transmission, making digital television a practical reality in the 1990s.<ref name="Barbero"/>\n\nA digital television service was proposed in 1986 by [[Nippon Telegraph and Telephone]] (NTT) and the [[Ministry of Posts and Telecommunications (Japan)|Ministry of Posts and Telecommunication]] (MPT) in Japan, where there were plans to develop an "Integrated Network System" service. However, it was not possible to practically implement such a digital television service until the adoption of DCT video compression technology made it possible in the early 1990s.<ref name="Lea"/>\n\nIn the mid-1980s, as Japanese [[consumer electronics]] firms forged ahead with the development of [[High-definition television|HDTV]] technology, the [[Multiple sub-Nyquist sampling encoding|MUSE]] analog format proposed by [[NHK]], a Japanese company, was seen as a pacesetter that threatened to eclipse U.S. electronics companies' technologies. Until June 1990, the Japanese MUSE standard, based on an analog system, was the front-runner among the more than 23 other technical concepts under consideration. Then, a U.S. company, General Instrument, demonstrated the possibility of a digital television signal. This breakthrough was of such significance that the [[Federal Communications Commission|FCC]] was persuaded to delay its decision on an ATV standard until a digitally-based standard could be developed.\n\nIn March 1990, when it became clear that a digital standard was possible, the FCC made a number of critical decisions. First, the Commission declared that the new ATV standard must be more than an enhanced analog signal, but be able to provide a genuine HDTV signal with at least twice the resolution of existing television images.(7) Then, to ensure that viewers who did not wish to buy a new digital television set could continue to receive conventional television broadcasts, it dictated that the new ATV standard must be capable of being "[[simulcast]]" on different channels.(8)The new ATV standard also allowed the new DTV signal to be based on entirely new design principles. Although incompatible with the existing [[NTSC]] standard, the new DTV standard would be able to incorporate many improvements.\n\nThe last standards adopted by the FCC did not require a single standard for scanning formats, [[aspect ratios]], or lines of resolution. This compromise resulted from a dispute between the [[consumer electronics]] industry (joined by some broadcasters) and the [[computer industry]] (joined by the [[film industry]] and some public interest groups) over which of the two scanning processes\u2014interlaced or progressive\u2014would be best suited for the newer digital HDTV compatible display devices.<ref name="bambooav.com">{{cite web|url=http://www.bambooav.com/information-about-interlaced-and-progressive-scan-signals.html |archive-url=https://web.archive.org/web/20090816184950/http://www.bambooav.com/information-about-interlaced-and-progressive-scan-signals.html |url-status=dead |archive-date=16 August 2009 |title=Information about interlaced and progressive scan signals |access-date=22 March 2015 }}</ref> Interlaced scanning, which had been specifically designed for older analogue CRT display technologies, scans even-numbered lines first, then odd-numbered ones. In fact, interlaced scanning can be looked at as the first video compression model as it was partly designed in the 1940s to double the image resolution to exceed the limitations of the television broadcast bandwidth. Another reason for its adoption was to limit the flickering on early CRT screens whose phosphor coated screens could only retain the image from the electron scanning gun for a relatively short duration.<ref>{{cite web|url=http://www.isfforum.com/FAQs/view/All-About-HDTV/What-s-the-Difference-between-Interlaced-and-Progressive-Video/33.html|title=What's the Difference between "Interlaced" and "Progressive" Video? \u2013 ISF Forum}}</ref> However interlaced scanning does not work as efficiently on newer display devices such as [[Lcd|Liquid-crystal (LCD)]], for example, which are better suited to a more frequent progressive refresh rate.<ref name="bambooav.com"/>\n\n[[Progressive scanning]], the format that the computer industry had long adopted for computer display monitors, scans every line in sequence, from top to bottom. Progressive scanning in effect doubles the amount of data generated for every full screen displayed in comparison to interlaced scanning by painting the screen in one pass in 1/60-second, instead of two passes in 1/30-second. The computer industry argued that progressive scanning is superior because it does not "flicker" on the new standard of display devices in the manner of interlaced scanning. It also argued that progressive scanning enables easier connections with the Internet, and is more cheaply converted to interlaced formats than vice versa. The film industry also supported progressive scanning because it offered a more efficient means of converting filmed programming into digital formats. For their part, the consumer electronics industry and broadcasters argued that interlaced scanning was the only technology that could transmit the highest quality pictures then (and currently) feasible, i.e., 1,080 lines per picture and 1,920 pixels per line. Broadcasters also favored interlaced scanning because their vast archive of interlaced programming is not readily compatible with a progressive format. [[William F. Schreiber]], who was director of the Advanced Television Research Program at the [[Massachusetts Institute of Technology]] from 1983 until his retirement in 1990, thought that the continued advocacy of interlaced equipment originated from consumer electronics companies that were trying to get back the substantial investments they made in the interlaced technology.<ref>{{cite web |url=http://www.cinemasource.com/articles/hist_politics_dtv.pdf|title=The history and politics of DTV|page=13}}</ref>\n\n[[Digital television transition]] started in late 2000s. All governments across the world set the deadline for analog shutdown by 2010s. Initially, the adoption rate was low, as the first digital tuner-equipped television sets were costly. But soon, as the price of digital-capable television sets dropped, more and more households were converting to digital television sets. The transition is expected to be completed worldwide by mid to late 2010s.\n\n {{main|Smart television}}\n{{Distinguish|Internet television|Internet Protocol television|Web television}}\n[[File:LG smart TV.jpg|thumb|right|upright=0.9|A smart TV]]\nThe advent of digital television allowed innovations like smart television sets. A smart television, sometimes referred to as connected TV or hybrid TV, is a television set or [[set-top box]] with integrated Internet and [[Web 2.0]] features, and is an example of [[technological convergence]] between computers, television sets and set-top boxes. Besides the traditional functions of television sets and set-top boxes provided through traditional Broadcasting media, these devices can also provide Internet TV, online [[interactive media]], [[over-the-top content]], as well as [[video on demand|on-demand]] [[streaming media]], and [[home network]]ing access. These TVs come pre-loaded with an operating system.<ref name="Techcrunch.com"/><ref name="businessinsider1">{{cite web|author=Steve Kovach | url=http://www.businessinsider.com/what-is-a-smart-tv-2010-12 |title=What Is A Smart TV? |work=Business Insider |date=8 December 2010 |access-date=17 January 2012}}</ref><ref>{{cite news|author=Carmi Levy Special to the Star |url=https://www.thestar.com/business/media/article/876278--future-of-television-is-online-and-on-demand |title=Future of television is online and on-demand |work=Toronto Star |date=15 October 2010 |access-date=17 January 2012}}</ref><ref>{{cite web|author=Jeremy Toeman 41 |url=http://mashable.com/2010/10/20/connected-tv-content-not-apps/ |title=Why Connected TVs Will Be About the Content, Not the Apps |publisher=Mashable.com |date=20 October 2010 |access-date=17 January 2012}}</ref>\n\nSmart TV should not to be confused with [[Internet TV]], [[Internet Protocol television]] (IPTV) or with [[Web TV]]. [[Internet television]] refers to the receiving of television content over the Internet instead of by traditional systems\u2014terrestrial, cable and satellite (although internet itself is received by these methods). IPTV is one of the emerging Internet television technology standards for use by television networks. [[Web television]] (WebTV) is a term used for programs created by a wide variety of companies and individuals for broadcast on Internet TV. A first patent was filed in 1994<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=19960510&DB=EPODOC&locale=en_EP&CC=FR&NR=2726670A1&KC=A1&ND=3 |title=espacenet \u2013 Original document |publisher=Worldwide.espacenet.com |access-date=17 January 2012}}</ref> (and extended the following year)<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/biblio?CC=US&NR=5905521A&KC=A&FT=D&ND=7&date=19990518&DB=EPODOC |title=espacenet \u2013 Bibliographic data |publisher=Worldwide.espacenet.com |access-date=17 January 2012}}</ref> for an "intelligent" television system, linked with data processing systems, by means of a digital or analog network. Apart from being linked to data networks, one key point is its ability to automatically download necessary software routines, according to a user's demand, and process their needs. Major TV manufacturers have announced production of smart TVs only, for middle-end and high-end TVs in 2015.<ref name="theverge.com"/><ref name="techtimes.com"/><ref name="cnet.com"/> Smart TVs have gotten more affordable compared to when they were first introduced, with 46 million of U.S. households having at least one as of 2019.<ref>Kats, Rimma (15 November 2018). [https://www.emarketer.com/content/how-many-households-own-a-smart-tv "How Many Households Own a Smart TV?"] ''[[eMarketer]]''. Retrieved 21 May 2021.</ref>\n\n {{main|3D television}}\n3D television conveys [[depth perception]] to the viewer by employing techniques such as [[stereoscopy|stereoscopic]] display, [[free viewpoint television|multi-view]] display, [[2D-plus-depth]], or any other form of [[3D display]]. Most modern 3D [[television set]]s use an [[active shutter 3D system]] or a [[polarized 3D system]], and some are [[Autostereoscopy|autostereoscopic]] without the need of glasses. Stereoscopic 3D television was demonstrated for the first time on 10 August 1928, by [[John Logie Baird]] in his company's premises at 133 Long Acre, London.<ref>{{cite web |url=http://www.bairdtelevision.com/stereo.html |title=How Stereoscopic Television is Shown |publisher=Baird Television website|access-date=18 September 2010| archive-url= https://web.archive.org/web/20101019045734/http://www.bairdtelevision.com/stereo.html| archive-date= 19 October 2010 | url-status=live}}</ref> Baird pioneered a variety of 3D television systems using electromechanical and cathode-ray tube techniques. The first 3D television was produced in 1935. The advent of digital television in the 2000s greatly improved 3D television sets. Although 3D television sets are quite popular for watching 3D home media such as on Blu-ray discs, 3D programming has largely failed to make inroads with the public. Many 3D television channels which started in the early 2010s were shut down by the mid-2010s. According to DisplaySearch 3D televisions shipments totaled 41.45 million units in 2012, compared with 24.14 in 2011 and 2.26 in 2010.<ref>{{cite news|title=3D TV-sales growth |url=http://www.globalpost.com/dispatch/news/yonhap-news-agency/130318/3d-tv-sales-growth |newspaper=globalpost.com |date=18 March 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130724082049/http://www.globalpost.com/dispatch/news/yonhap-news-agency/130318/3d-tv-sales-growth |archive-date=24 July 2013 }}</ref> As of late 2013, the number of 3D TV viewers started to decline.<ref>{{cite news|title=Future looks flat for 3D TV|url=https://www.smh.com.au/digital-life/digital-life-news/future-looks-flat-for-3d-tv-20130814-2rv1q.html|newspaper=The Sydney Morning Herald|date=15 August 2013}}</ref><ref>{{cite news|title=Is 3D TV dead? ESPN 3D to shut down by end of 2013|url=https://www.theverge.com/2013/6/12/4422874/espn-3d-to-shut-down-by-end-of-2013|author=Chris Welch|newspaper=The Verge|date=12 June 2013}}</ref><ref>{{cite news|title=Why 3D TV is such a turn-off|url=http://www.iol.co.za/scitech/technology/software/why-3d-tv-is-such-a-turn-off-1.1755980|publisher=Iol Scitech|author=Guy Walters|date=25 September 2014}}</ref><ref>{{cite news|title=Is 3D dead\u2026again?|url=http://techday.com/netguide/news/is-3d-deadagain/192995/|publisher=Techday|author=Donovan Jackson|date=29 September 2014}}</ref><ref>{{cite news|title=3D TV falls further out of favour as Sky omits Premier League matches from schedule|url=https://www.telegraph.co.uk/culture/tvandradio/11102038/3D-TV-falls-further-out-of-favour-as-Sky-omits-Premier-League-matches-from-schedule.html|work=The Telegraph|author=Hannah Furness|date=17 September 2014}}</ref>"}},
{"article_title": "Transistor", "pageid": "30011", "revid": "1062773775", "timestamp": "2021-12-30T12:46:54Z", "history_paths": [["Transistor --- Introduction ---", "History"]], "categories": ["transistors", "1947 in computing", "1947 in technology", "20th-century inventions", "american inventions", "bell labs", "computer-related introductions in 1947", "electrical components", "hungarian inventions", "semiconductor devices"], "heading_tree": {"Transistor --- Introduction ---": {"History": {"Bipolar transistors": {}, "MOSFET (MOS transistor)": {}}, "Importance": {}, "Simplified operation": {"Transistor as a switch": {}, "Transistor as an amplifier": {}}, "Comparison with vacuum tubes": {"Advantages": {}, "Limitations": {}}, "Types": {"Classification": {}, "Mnemonics": {}, "Field-effect transistor (FET)": {"Metal\u2013oxide\u2013semiconductor FET (MOSFET)": {}}, "Bipolar junction transistor (BJT)": {}, "Usage of MOSFETs and BJTs": {}, "Other transistor types": {}}, "Device identification": {"Joint Electron Device Engineering Council (JEDEC)": {}, "Japanese Industrial Standard (JIS)": {}, "European Electronic Component Manufacturers Association (EECA)": {}, "Proprietary": {}, "Naming problems": {}}, "Construction": {"Semiconductor material": {}, "Packaging": {"Flexible transistors": {}}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Transistor --- Introduction ---|History": "{{Main|History of the transistor}}\n[[File:Julius Edgar Lilienfeld (1881-1963).jpg|thumb|130px|[[Julius Edgar Lilienfeld]] proposed the concept of a [[field-effect transistor]] in 1925.]]\n\nThe [[thermionic]] [[triode]], a [[vacuum tube]] invented in 1907, enabled amplified [[radio]] technology and long-distance [[telephony]]. The triode, however, was a fragile device that consumed a substantial amount of power. In 1909, [[physicist]] [[William Eccles (physicist)|William Eccles]] discovered the crystal diode oscillator.<ref>{{Cite book | url=https://books.google.com/books?id=YiJaEAUj258C&q=Eccles+Oscillator+Galena&pg=PA430 | title=Concise Encyclopedia of Building and Construction Materials| isbn=9780262132480| last1=Moavenzadeh| first1=Fred| year=1990}}</ref> Austro-Hungarian physicist [[Julius Edgar Lilienfeld]] filed a patent for a [[field-effect transistor]] (FET) in Canada in 1925,<ref>{{Cite book | url=https://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=19270719&DB=&CC=CA&NR=272437A&KC=A&locale=en_EP# | title=Specification of electric current control mechanism patent application| last1=Lilienfeld| first1=Julius Edgar| year=1927}}</ref> which was intended to be a [[Solid-state (electronics)|solid-state]] replacement for the triode.<ref>Vardalas, John (May 2003) [http://www.todaysengineer.org/2003/May/history.asp Twists and Turns in the Development of the Transistor] {{webarchive|url=https://web.archive.org/web/20150108082709/http://www.todaysengineer.org/2003/May/history.asp |date=January 8, 2015 }} ''IEEE-USA Today's Engineer''.</ref><ref>Lilienfeld, Julius Edgar, "Method and apparatus for controlling electric current" {{US patent|1745175}} January 28, 1930 (filed in Canada 1925-10-22, in US October 8, 1926).</ref> Lilienfeld also filed identical patents in the United States in 1926<ref>{{cite web|title=Method And Apparatus For Controlling Electric Currents|publisher=United States Patent and Trademark Office|url=http://www.google.com/patents?id=uBFMAAAAEBAJ&printsec=abstract#v=onepage&q&f=false}}</ref> and 1928.<ref>{{cite web|title=Amplifier For Electric Currents|publisher=United States Patent and Trademark Office| url=http://www.google.com/patents?id=jvhAAAAAEBAJ&printsec=abstract#v=onepage&q&f=false}}</ref><ref>{{cite web| title=Device For Controlling Electric Current|publisher=United States Patent and Trademark Office| url=http://www.google.com/patents?id=52BQAAAAEBAJ&printsec=abstract#v=onepage&q&f=false}}</ref> However, Lilienfeld did not publish any research articles about his devices nor did his patents cite any specific examples of a working prototype. Because the production of high-quality [[semiconductor]] materials was still decades away, Lilienfeld's solid-state amplifier ideas would not have found practical use in the 1920s and 1930s, even if such a device had been built.<ref name="todaysengineer.org">{{cite web|title=Twists and Turns in the Development of the Transistor|publisher=Institute of Electrical and Electronics Engineers, Inc.|url=http://www.todaysengineer.org/2003/May/history.asp|url-status=dead|archive-url=https://web.archive.org/web/20150108082709/http://www.todaysengineer.org/2003/May/history.asp|archive-date=January 8, 2015}}</ref> In 1934, German inventor [[Oskar Heil]] patented a similar device in Europe.<ref>[http://v3.espacenet.com/publicationDetails/biblio?CC=GB&NR=439457&KC=&FT=E Heil, Oskar, "Improvements in or relating to electrical amplifiers and other control arrangements and devices"], Patent No. GB439457, European Patent Office, filed in Great Britain 1934-03-02, published December 6, 1935 (originally filed in Germany March 2, 1934).</ref>\n\n [[File:Bardeen Shockley Brattain 1948.JPG|thumb|left|[[John Bardeen]], [[William Shockley]] and [[Walter Brattain]] at [[Bell Labs]] in 1948. Bardeen and Brattain invented the [[point-contact transistor]] in 1947 and Shockley the [[bipolar junction transistor]] in 1948.]]\n[[File:Replica-of-first-transistor.jpg|thumb|upright=1.4|A replica of the first working transistor, a [[point-contact transistor]] invented in 1947.]]\n{{See|Point-contact transistor|Bipolar junction transistor}}\n\nFrom November 17, 1947, to December 23, 1947, [[John Bardeen]] and [[Walter Brattain]] at [[AT&T Corporation|AT&T]]'s [[Bell Labs]] in [[Murray Hill, New Jersey]], performed experiments and observed that when two gold point contacts were applied to a crystal of [[germanium]], a signal was produced with the output power greater than the input.<ref>{{cite web| title=November 17 \u2013 December 23, 1947: Invention of the First Transistor| publisher=American Physical Society| url=http://www.aps.org/publications/apsnews/200011/history.cfm| url-status=live| archive-url=https://web.archive.org/web/20130120065607/http://www.aps.org/publications/apsnews/200011/history.cfm| archive-date=January 20, 2013| df=mdy-all}}</ref> Solid State Physics Group leader [[William Shockley]] saw the potential in this, and over the next few months worked to greatly expand the knowledge of semiconductors. The term ''transistor'' was coined by [[John R. Pierce]] as a contraction of the term ''[[transresistance]]''.<ref>{{cite book|editor=Millman, S. |title=A History of Engineering and Science in the Bell System, Physical Science (1925\u20131980)|  page=102|year=1983|publisher=AT&T Bell Laboratories}}</ref><ref>{{cite book|author=Bodanis, David |title=Electric Universe|publisher=Crown Publishers, New York|year=2005|isbn=978-0-7394-5670-5}}</ref><ref>{{cite encyclopedia|encyclopedia=American Heritage Dictionary| edition=3rd| year=1992|publisher=Houghton Mifflin| location=Boston| title=transistor}}</ref> According to Lillian Hoddeson and Vicki Daitch, authors of a biography of John Bardeen, Shockley had proposed that Bell Labs' first patent for a transistor should be based on the field-effect and that he be named as the inventor. Having unearthed Lilienfeld's patents that went into obscurity years earlier, lawyers at Bell Labs advised against Shockley's proposal because the idea of a field-effect transistor that used an electric field as a "grid" was not new. Instead, what Bardeen, Brattain, and Shockley invented in 1947 was the first [[point-contact transistor]].<ref name="todaysengineer.org"/> In acknowledgement of this accomplishment, Shockley, Bardeen, and Brattain were jointly awarded the 1956 [[Nobel Prize in Physics]] "for their researches on semiconductors and their discovery of the transistor effect".<ref>{{cite web|title=The Nobel Prize in Physics 1956|url=http://nobelprize.org/nobel_prizes/physics/laureates/1956/|publisher=nobelprize.org|url-status=live|archive-url=https://web.archive.org/web/20070312091604/http://nobelprize.org/nobel_prizes/physics/laureates/1956/|archive-date=March 12, 2007}}</ref><ref name="Guarnieri 1">{{Cite journal|last=Guarnieri|first=M.|year=2017|title=Seventy Years of Getting Transistorized|journal=IEEE Industrial Electronics Magazine|volume=11|issue=4|pages=33\u201337|doi=10.1109/MIE.2017.2757775|s2cid=38161381|hdl=11577/3257397|hdl-access=free}}</ref>\n\nShockley's research team initially attempted to build a field-effect transistor (FET), by trying to modulate the conductivity of a [[semiconductor]], but was unsuccessful, mainly due to problems with the [[surface states]], the [[dangling bond]], and the [[germanium]] and [[copper]] compound materials. In the course of trying to understand the mysterious reasons behind their failure to build a working FET, this led them instead to invent the bipolar [[point-contact transistor|point-contact]] and [[junction transistor]]s.<ref name="Lee">{{cite book |last1=Lee |first1=Thomas H. |title=The Design of CMOS Radio-Frequency Integrated Circuits |journal=Soldering & Surface Mount Technology |date=2003 |volume=16 |issue=2 |publisher=[[Cambridge University Press]] |doi=10.1108/ssmt.2004.21916bae.002 |isbn=9781139643771 |s2cid=108955928 |url=https://www.semanticscholar.org/paper/The-Design-of-CMOS-Radio-Frequency-Integrated-Ellis/c0018d231b4960f7a6c4f581b086212d7f8b0d15?p2df}}</ref><ref name="Puers">{{cite book |last1=Puers |first1=Robert |last2=Baldi |first2=Livio |last3=Voorde |first3=Marcel Van de |last4=Nooten |first4=Sebastiaan E. van |title=Nanoelectronics: Materials, Devices, Applications, 2 Volumes |date=2017 |publisher=[[John Wiley & Sons]] |isbn=9783527340538 |page=14 |url=https://books.google.com/books?id=JOqVDgAAQBAJ&pg=PA14}}</ref>\n\n[[File:Herbert F. Matar\u00e9 1950.png|thumb|130px|left|[[Herbert Matar\u00e9]] in 1950. He independently invented a point-contact transistor in June 1948.]]\n\nIn 1948, the point-contact transistor was independently invented by German physicists [[Herbert Matar\u00e9]] and [[Heinrich Welker]] while working at the ''[[Compagnie des Freins et Signaux Westinghouse]]'', a [[Westinghouse Electric (1886)|Westinghouse]] subsidiary located in [[Paris]]. Matar\u00e9 had previous experience in developing [[Cat's-whisker detector|crystal rectifiers]] from [[silicon]] and germanium in the German [[radar]] effort during [[World War II]]. Using this knowledge, he began researching the phenomenon of "interference" in 1947. By June 1948, witnessing currents flowing through point-contacts, Matar\u00e9 produced consistent results using samples of germanium produced by Welker, similar to what Bardeen and Brattain had accomplished earlier in December 1947. Realizing that Bell Labs' scientists had already invented the transistor before them, the company rushed to get its "transition" into production for amplified use in France's telephone network and filed his first transistor patent application on August 13, 1948.<ref>{{Patent|FR|1010427|H. F. Matar\u00e9 / H. Welker / Westinghouse: "Nouveau syt\u00e8me crystallin \u00e0 plusieur \u00e9lectrodes r\u00e9alisant des relais de effects \u00e9lectroniques" filed on August 13, 1948}}</ref><ref>{{patent|US|2673948|H. F. Matar\u00e9 / H. Welker / Westinghouse, "Crystal device for controlling electric currents by means of a solid semiconductor" French priority August 13, 1948}}</ref><ref>{{cite web|title=1948, The European Transistor Invention|publisher=Computer History Museum|url=http://www.computerhistory.org/semiconductor/timeline/1948-European.html|url-status=live|archive-url=https://web.archive.org/web/20120929202704/http://www.computerhistory.org/semiconductor/timeline/1948-European.html|archive-date=September 29, 2012}}</ref>\n\nThe first [[bipolar junction transistor]]s were invented by Bell Labs' William Shockley, which applied for patent (2,569,347) on June 26, 1948. On April 12, 1950, Bell Labs chemists [[Gordon Teal]] and [[Morgan Sparks]] had successfully produced a working bipolar NPN junction amplifying germanium transistor. Bell Labs had announced the discovery of this new "sandwich" transistor in a press release on July 4, 1951.<ref>[http://www.computerhistory.org/siliconengine/first-grown-junction-transistors-fabricated/ 1951: First Grown-Junction Transistors Fabricated] {{webarchive|url=https://web.archive.org/web/20170404035446/http://www.computerhistory.org/siliconengine/first-grown-junction-transistors-fabricated/ |date=April 4, 2017 }}</ref><ref>{{cite web |url=https://www.pbs.org/transistor/science/info/junctw.html |title=A Working Junction Transistor |website=[[PBS]] |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170703002246/http://www.pbs.org/transistor/science/info/junctw.html |archive-date=July 3, 2017 }}</ref>\n\n[[File: Philco Surface Barrier transistor=1953.jpg|thumb|upright=1.4|Philco surface-barrier transistor developed and produced in 1953]]\n\nThe first high-frequency transistor was the [[surface-barrier transistor|surface-barrier germanium transistor]] developed by [[Philco]] in 1953, capable of operating at frequencies up to {{nowrap|60 MHz}}.<ref>{{cite journal| journal=Proceedings of the IRE| date=December 1953| author=Bradley, W.E. |title=The Surface-Barrier Transistor: Part I-Principles of the Surface-Barrier Transistor| volume=41| issue=12| pages=1702\u20131706| doi=10.1109/JRPROC.1953.274351| s2cid=51652314}}</ref> These were made by etching depressions into an n-type germanium base from both sides with jets of [[Indium(III) sulfate]] until it was a few ten-thousandths of an inch thick. [[Indium]] electroplated into the depressions formed the collector and emitter.<ref>Wall Street Journal, December 4, 1953, page 4, Article "Philco Claims Its Transistor Outperforms Others Now In Use"</ref><ref>Electronics magazine, January 1954, Article "Electroplated Transistors Announced"</ref>\n\nAT&T first used transistors in telecommunications equipment in circuits of the No. 4A Toll Crossbar Switching System in 1953 for selecting trunk circuits from routing information encoded on translator cards.<ref>P. Mallery, ''Transistors and Their Circuits in the 4A Toll Crossbar Switching System'', AIEE Transactions, September 1953, p.388</ref> The Western Electric No. 3A [[phototransistor]] read the mechanical encoding from punched metal cards.\n\nThe first "prototype" pocket [[transistor radio]] was shown by INTERMETALL (a company founded by [[Herbert Matar\u00e9]] in 1952) at the [[Internationale Funkausstellung Berlin|''Internationale Funkausstellung D\u00fcsseldorf'']] between August 29, 1953 and September 6, 1953.<ref>1953 Foreign Commerce Weekly; Volume 49; pp.23</ref><ref>{{cite news |url=https://www.welt.de/welt_print/article2721871/Der-deutsche-Erfinder-des-Transistors.html |title=''Der deutsche Erfinder des Transistors \u2013 Nachrichten Welt Print \u2013 DIE WELT'' |publisher=Welt.de |date=November 23, 2011 |access-date=May 1, 2016 |url-status=live |archive-url=https://web.archive.org/web/20160515182422/http://www.welt.de/welt_print/article2721871/Der-deutsche-Erfinder-des-Transistors.html |archive-date=May 15, 2016 |newspaper=Die Welt }}</ref> The first "production" pocket transistor radio was the [[Regency TR-1]], released in October 1954.<ref name="Guarnieri 1" /> Produced as a joint venture between  the Regency Division of Industrial Development Engineering Associates, I.D.E.A. and [[Texas Instruments]] of Dallas Texas, the TR-1 was manufactured in Indianapolis, Indiana.  It was a near pocket-sized radio featuring 4 transistors and one germanium diode. The industrial design was outsourced to the Chicago firm of Painter, Teague and Petertil. It was initially released in one of six different colours:  black, ivory, mandarin red, cloud grey, mahogany and olive green.  Other colours were to shortly follow.<ref>{{cite web |url=http://www.regencytr1.com/ |title=Regency TR-1 Transistor Radio History |access-date=April 10, 2006 |url-status=live |archive-url=https://web.archive.org/web/20041021040145/http://www.regencytr1.com/ |archive-date=October 21, 2004 }}</ref><ref>{{cite web |url=http://www.ericwrobbel.com/books/regency.htm |title=The Regency TR-1 Family |access-date=April 10, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170427155821/http://www.ericwrobbel.com/books/regency.htm |archive-date=April 27, 2017 }}</ref><ref>{{cite web |url=http://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=3886 |title=Regency manufacturer in USA, radio technology from United St |access-date=April 10, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170410214244/http://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=3886 |archive-date=April 10, 2017 }}</ref>\n\nThe first "production" all-transistor car radio was developed by Chrysler and [[Philco]] corporations and it was announced in the April 28, 1955 edition of the Wall Street Journal. Chrysler had made the all-transistor car radio, Mopar model 914HR, available as an option starting in fall 1955 for its new line of 1956 Chrysler and Imperial cars which first hit the dealership showroom floors on October 21, 1955.<ref>Wall Street Journal, "Chrysler Promises Car Radio With Transistors Instead of Tubes in '56", April 28, 1955, page 1</ref><ref>{{cite web|last=Hirsh |first=Rick |url=http://www.allpar.com/stereo/Philco/index.html |title=Philco's All-Transistor Mopar Car Radio |publisher=Allpar.com |access-date=February 18, 2015}}</ref><ref>{{cite web|url=http://www.fcanorthamerica.com/company/Heritage/Pages/Chrysler-Heritage-1950.aspx|title=FCA North America - Historical Timeline 1950-1959|website=www.fcanorthamerica.com}}</ref>\n\nThe [[Sony]] TR-63, released in 1957, was the first mass-produced transistor radio, leading to the mass-market penetration of transistor radios.<ref name="Skrabec">{{cite book | last1  = Skrabec | first1 = Quentin R., Jr. | title  = The 100 Most Significant Events in American Business: An Encyclopedia | publisher = ABC-CLIO  | date   = 2012 | pages  = 195\u20137 | url    = https://books.google.com/books?id=2kc69qrid9oC&pg=PA195 | isbn   = 978-0313398636 }}</ref> The TR-63 went on to sell seven million units worldwide by the mid-1960s.<ref>{{cite news |last1=Snook |first1=Chris J. |title=The 7 Step Formula Sony Used to Get Back On Top After a Lost Decade |url=https://www.inc.com/chris-j-snook/sonys-7-step-formula-for-entrepreneurial-success-business-longevity.html |work=[[Inc. (magazine)|Inc.]] |date=November 29, 2017}}</ref> Sony's success with transistor radios led to transistors replacing vacuum tubes as the dominant [[electronic technology]] in the late 1950s.<ref>{{cite magazine |last1=Kozinsky |first1=Sieva |title=Education and the Innovator's Dilemma |url=https://www.wired.com/insights/2014/01/education-innovators-dilemma/ |magazine=[[Wired (magazine)|Wired]] |access-date=October 14, 2019 |date=January 8, 2014}}</ref>\n\nThe first working silicon transistor was developed at Bell Labs on January 26, 1954, by [[Morris Tanenbaum]]. The first commercial silicon transistor was produced by [[Texas Instruments]] in 1954. This was the work of [[Gordon Teal]], an expert in growing crystals of high purity, who had previously worked at Bell Labs.<ref>{{cite journal| journal=IEEE Spectrum| title=The Lost History of the Transistor| author=Riordan, Michael| date=May 2004| pages=48\u201349| url=https://spectrum.ieee.org/biomedical/devices/the-lost-history-of-the-transistor| url-status=live| archive-url=https://web.archive.org/web/20150531113132/https://spectrum.ieee.org/biomedical/devices/the-lost-history-of-the-transistor| archive-date=May 31, 2015| df=mdy-all}}</ref><ref>Chelikowski, J. (2004) "Introduction: Silicon in all its Forms", p. 1 in ''Silicon: evolution and future of a technology''. P. Siffert and E. F. Krimmel (eds.). Springer, {{ISBN|3-540-40546-1}}.</ref><ref>McFarland, Grant (2006) ''Microprocessor design: a practical guide from design planning to manufacturing''. McGraw-Hill Professional. p. 10. {{ISBN|0-07-145951-0}}.</ref>\n\n {{Main|MOSFET}}\n{{multiple image\n | align  = right\n | direction = \n | image1 = Atalla1963.png\n | width1 = 139\n | image2 = Dawon Kahng.jpg\n | width2 = 144\n | footer = [[Mohamed Atalla]] (left) and [[Dawon Kahng]] (right) invented the [[MOSFET]] (MOS transistor) at Bell Labs in 1959.\n}}\n\nSemiconductor companies initially focused on [[junction transistor]]s in the early years of the [[semiconductor industry]]. The junction transistor was a relatively bulky device that was difficult to [[mass-production|mass-produce]], which limited it to several specialized applications. [[Field-effect transistor]]s (FETs) were theorized as potential alternatives to junction transistors, but researchers initially could not get FETs to work properly, largely due to the troublesome [[surface state]] barrier that prevented the external [[electric field]] from penetrating the material.<ref name="Moskowitz">{{cite book |last1=Moskowitz |first1=Sanford L. |title=Advanced Materials Innovation: Managing Global Technology in the 21st century |date=2016 |publisher=[[John Wiley & Sons]] |isbn=9780470508923 |page=168 |url=https://books.google.com/books?id=2STRDAAAQBAJ&pg=PA168}}</ref>\n\nIn the 1950s, Egyptian engineer [[Mohamed Atalla]] investigated the surface properties of [[silicon]] semiconductors at Bell Labs, where he proposed a new method of [[semiconductor device fabrication]], coating a [[silicon wafer]] with an insulating layer of [[silicon oxide]] so that electricity could reliably penetrate to the conducting silicon below, overcoming the surface states that prevented electricity from reaching the semiconducting layer. This is known as [[surface passivation]], a method that became critical to the [[semiconductor industry]] as it later made possible the mass-production of silicon [[integrated circuit]]s.<ref name="atalla">{{cite web|title=Martin Atalla in Inventors Hall of Fame, 2009|url=https://www.invent.org/inductees/martin-john-m-atalla|access-date=June 21, 2013}}</ref><ref name="kahng">{{cite web |title=Dawon Kahng |url=https://www.invent.org/inductees/dawon-kahng |website=[[National Inventors Hall of Fame]] |access-date=June 27, 2019}}</ref> He presented his findings in 1957.<ref>{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |url=https://archive.org/details/historysemicondu00loje_697 |url-access=limited |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |page=[https://archive.org/details/historysemicondu00loje_697/page/n128 120]}}</ref> Building on his surface passivation method, he developed the [[metal\u2013oxide\u2013semiconductor]] (MOS) process.<ref name="atalla"/> He proposed the MOS process could be used to build the first working silicon FET, which he began working on building with the help of his Korean colleague [[Dawon Kahng]].<ref name="atalla"/>\n\nThe [[metal\u2013oxide\u2013semiconductor field-effect transistor]] (MOSFET), or ''MOS transistor'', was invented by Mohamed Atalla and Dawon Kahng in 1959.<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960 - Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]]}}</ref><ref name="Lojek">{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |url=https://archive.org/details/historysemicondu00loje_697 |url-access=limited |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |pages=[https://archive.org/details/historysemicondu00loje_697/page/n327 321]\u20133}}</ref> The MOSFET was the first truly compact transistor that could be miniaturized and mass-produced for a wide range of uses.<ref name="Moskowitz"/> With its [[MOSFET scaling|high scalability]],<ref>{{cite journal |last1=Motoyoshi |first1=M. |title=Through-Silicon Via (TSV) |journal=Proceedings of the IEEE |date=2009 |volume=97 |issue=1 |pages=43\u201348 |doi=10.1109/JPROC.2008.2007462 |s2cid=29105721 |url=https://pdfs.semanticscholar.org/8a44/93b535463daa7d7317b08d8900a33b8cbaf4.pdf |archive-url=https://web.archive.org/web/20190719120523/https://pdfs.semanticscholar.org/8a44/93b535463daa7d7317b08d8900a33b8cbaf4.pdf |url-status=dead |archive-date=2019-07-19 |issn=0018-9219}}</ref> and much lower power consumption and higher density than bipolar junction transistors,<ref>{{cite news |title=Transistors Keep Moore's Law Alive |url=https://www.eetimes.com/author.asp?section_id=36&doc_id=1334068 |access-date=July 18, 2019 |work=[[EETimes]] |date=December 12, 2018}}</ref> the MOSFET made it possible to build [[Large scale integration|high-density]] integrated circuits,<ref name="computerhistory-transistor">{{cite web |title=Who Invented the Transistor? |url=https://www.computerhistory.org/atchm/who-invented-the-transistor/ |website=[[Computer History Museum]] |date=December 4, 2013 |access-date=July 20, 2019}}</ref> allowing the integration of more than 10,000 transistors in a single IC.<ref>{{cite journal |last1=Hittinger |first1=William C. |title=Metal-Oxide-Semiconductor Technology |journal=Scientific American |date=1973 |volume=229 |issue=2 |pages=48\u201359 |issn=0036-8733|jstor=24923169 |doi=10.1038/scientificamerican0873-48 |bibcode=1973SciAm.229b..48H }}</ref>\n\n[[CMOS]] (complementary [[MOSFET|MOS]]) was invented by [[Chih-Tang Sah]] and [[Frank Wanlass]] at [[Fairchild Semiconductor]] in 1963.<ref name="computerhistory1963">{{cite web |title=1963: Complementary MOS Circuit Configuration is Invented |url=https://www.computerhistory.org/siliconengine/complementary-mos-circuit-configuration-is-invented/ |website=[[Computer History Museum]] |access-date=July 6, 2019}}</ref> The first report of a [[floating-gate MOSFET]] was made by Dawon Kahng and [[Simon Sze]] in 1967.<ref>D. Kahng and S. M. Sze, "A floating gate and its application to memory devices", ''The Bell System Technical Journal'', vol. 46, no. 4, 1967, pp. 1288\u20131295</ref> A [[double-gate]] MOSFET was first demonstrated in 1984 by [[Electrotechnical Laboratory]] researchers Toshihiro Sekigawa and Yutaka Hayashi.<ref>{{cite book |last1=Colinge |first1=J.P. |title=FinFETs and Other Multi-Gate Transistors |date=2008 |publisher=Springer Science & Business Media |isbn=9780387717517 |page=11 |url=https://books.google.com/books?id=t1ojkCdTGEEC&pg=PA11}}</ref><ref>{{cite journal |last1=Sekigawa |first1=Toshihiro |last2=Hayashi |first2=Yutaka |title=Calculated threshold-voltage characteristics of an XMOS transistor having an additional bottom gate |journal=Solid-State Electronics |date=August 1, 1984 |volume=27 |issue=8 |pages=827\u2013828 |doi=10.1016/0038-1101(84)90036-4 |issn=0038-1101|bibcode=1984SSEle..27..827S }}</ref> [[FinFET]] (fin field-effect transistor), a type of 3D non-planar [[Multigate device|multi-gate]] MOSFET, originated from the research of Digh Hisamoto and his team at [[Hitachi|Hitachi Central Research Laboratory]] in 1989.<ref>{{cite web |title=IEEE Andrew S. Grove Award Recipients |url=https://www.ieee.org/about/awards/bios/grove-recipients.html |website=[[IEEE Andrew S. Grove Award]] |publisher=[[Institute of Electrical and Electronics Engineers]] |access-date=July 4, 2019}}</ref><ref>{{cite web |title=The Breakthrough Advantage for FPGAs with Tri-Gate Technology |url=https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/wp/wp-01201-fpga-tri-gate-technology.pdf |publisher=[[Intel]] |year=2014 |access-date=July 4, 2019}}</ref>"}},
{"article_title": "Turbine", "pageid": "30848", "revid": "1035796089", "timestamp": "2021-07-27T18:32:35Z", "history_paths": [["Turbine --- Introduction ---"]], "categories": ["turbines", "jet engines", "power engineering", "gas technologies"], "heading_tree": {"Turbine --- Introduction ---": {"{{anchor|Theory of operation}} Operation theory": {}, "Types": {}, "Uses": {}, "See also": {}, "Notes": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Turbine --- Introduction ---": "{{short description|Rotary mechanical device that extracts energy from a fluid flow}}\n{{Other uses}}\n[[File:Dampfturbine Montage01.jpg|thumb|upright=1.3|A [[steam turbine]] with the case opened.]]\n\nA '''turbine''' ({{IPAc-en|'|t|\u025c\u02d0r|b|a\u026a|n}} or {{IPAc-en|'|t|\u025c\u02d0r|b|\u026a|n}}) (from the Greek {{lang|grc|\u03c4\u03cd\u03c1\u03b2\u03b7}}, ''tyrb\u0113'', or [[Latin]] ''turbo'', meaning [[vortex]])<ref>{{cite web|title=turbine|url=http://www.etymonline.com/index.php?allowed_in_frame=0&search=turbine&searchmode=none}}{{cite dictionary|title=turbid|url=http://www.etymonline.com/index.php?term=turbid&allowed_in_frame=0|dictionary=[[Online Etymology Dictionary]]}}</ref><ref>{{LSJ|tu/rbh|\u03c4\u03cd\u03c1\u03b2\u03b7|ref}}.</ref> is a rotary mechanical device that extracts [[energy]] from a [[fluid]] flow and converts it into useful [[Work (physics)|work]]. The work produced by a turbine can be used for generating electrical power when combined with a [[electric generator|generator]].<ref name = "Munson">Munson, Bruce Roy, T. H. Okiishi, and Wade W. Huebsch. "Turbomachines." Fundamentals of Fluid Mechanics. 6th ed. Hoboken, NJ: J. Wiley & Sons, 2009. Print.</ref> A turbine is a [[turbomachinery|turbomachine]] with at least one moving part called a rotor assembly, which is a shaft or drum with [[Turbine blade|blades]] attached. Moving fluid acts on the blades so that they move and impart rotational energy to the rotor. Early turbine examples are [[windmill]]s and [[waterwheel]]s.\n\n[[Gas turbine|Gas]], [[steam turbine|steam]], and [[water turbine|water]] turbines have a casing around the blades that contains and controls the working fluid. Credit for invention of the steam turbine is given both to Anglo-Irish engineer [[Charles Algernon Parsons|Sir Charles Parsons]] (1854\u20131931) for invention of the reaction turbine, and to Swedish engineer [[Gustaf de Laval]] (1845\u20131913) for invention of the impulse turbine. Modern steam turbines frequently employ both reaction and impulse in the same unit, typically varying the [[degree of reaction]] and impulse from the blade root to its periphery. [[Hero of Alexandria]] demonstrated the turbine principle in an [[aeolipile]] in the first century AD and [[Vitruvius]] mentioned them around 70 BC.\n\nThe word "turbine" was coined in 1822 by the French mining engineer [[Claude Burdin]] from the Greek {{lang|grc|\u03c4\u03cd\u03c1\u03b2\u03b7}}, ''tyrb\u0113'', meaning "[[vortex]]" or "whirling", in a memo, "Des turbines hydrauliques ou machines rotatoires \u00e0 grande vitesse", which he submitted to the [[French Academy of Sciences|Acad\u00e9mie royale des sciences]] in Paris.<ref>In 1822, Claude Burdin submitted his memo "Des turbines hydrauliques ou machines rotatoires \u00e0 grande vitesse" (Hydraulic turbines or high-speed rotary machines) to the Acad\u00e9mie royale des sciences in Paris.  (See:  ''Annales de chimie et de physique'', vol. 21, [https://books.google.com/books?id=rzNCAAAAcAAJ&pg=PA183#v=onepage&q&f=false page 183] (1822).)  However, it was not until 1824 that a committee of the Acad\u00e9mie (composed of Prony, Dupin, and Girard) reported favorably on Burdin's memo.  See: Prony and Girard (1824) [https://books.google.com/books?id=03BRAAAAYAAJ&pg=RA1-PA207#v=onepage&q&f=false "Rapport sur le m\u00e9moire de M. Burdin intitul\u00e9: Des turbines hydrauliques ou machines rotatoires \u00e0 grande vitesse"] (Report on the memo of Mr. Burdin titled:  Hydraulic turbines or high-speed rotary machines), ''Annales de chimie et de physique'', vol. 26, pages 207-217.</ref> [[Benoit Fourneyron]], a former student of Claude Burdin, built the first practical water turbine.\n[[File:WWS Pneumaticlamp.ogg|thumb|Humming of a small pneumatic turbine used in a German 1940s-vintage [[safety lamp]]]]\n\n [[File:Turbines impulse v reaction.svg|thumb|upright=1.5|Schematic of impulse and reaction turbines, where the rotor is the rotating part, and the [[stator]] is the stationary part of the machine.]]\nA working fluid contains [[potential energy]] (pressure [[head (hydraulic)|head]]) and [[kinetic energy]] (velocity head). The fluid may be [[compressibility|compressible]] or [[incompressible fluid|incompressible]]. Several physical principles are employed by turbines to collect this energy:\n\n[[Impulse (physics)|Impulse]] turbines change the direction of flow of a high velocity fluid or gas jet. The resulting impulse spins the turbine and leaves the fluid flow with diminished kinetic energy. There is no pressure change of the fluid or gas in the [[turbine blade]]s (the moving blades), as in the case of a steam or gas turbine, all the pressure drop takes place in the stationary blades (the nozzles). Before reaching the turbine, the fluid's ''pressure head'' is changed to ''velocity head'' by accelerating the fluid with a [[nozzle]].  [[Pelton wheel]]s and [[Steam turbine|de Laval turbine]]s use this process exclusively. Impulse turbines do not require a pressure casement around the rotor since the fluid jet is created by the nozzle prior to reaching the blades on the rotor. [[Newton's laws of motion#Newton's second law|Newton's second law]] describes the transfer of energy for impulse turbines.  Impulse turbines are most efficient for use in cases where the flow is low and the inlet pressure is high. <ref name = "Munson"/>\n\n[[Reaction (physics)|Reaction]] turbines develop [[torque]] by reacting to the gas or fluid's pressure or mass.  The pressure of the gas or fluid changes as it passes through the turbine rotor blades.<ref name = "Munson"/> A pressure casement is needed to contain the working fluid as it acts on the turbine stage(s) or the turbine must be fully immersed in the fluid flow (such as with wind turbines). The casing contains and directs the working fluid and, for water turbines, maintains the suction imparted by the [[draft tube]]. [[Francis turbine]]s and most [[steam turbine]]s use this concept. For compressible working fluids, multiple turbine stages are usually used to harness the expanding gas efficiently. [[Newton's laws of motion#Newton's third law|Newton's third law]] describes the transfer of energy for reaction turbines.  Reaction turbines are better suited to higher flow velocities or applications where the fluid head (upstream pressure) is low. <ref name = "Munson"/>\n\nIn the case of steam turbines, such as would be used for marine applications or for land-based electricity generation, a Parsons-type reaction turbine would require approximately double the number of blade rows as a de Laval-type impulse turbine, for the same degree of thermal energy conversion. Whilst this makes the Parsons turbine much longer and heavier, the overall efficiency of a reaction turbine is slightly higher than the equivalent impulse turbine for the same thermal energy conversion.\n\nIn practice, modern turbine designs use both reaction and impulse concepts to varying degrees whenever possible. [[Wind turbine]]s use an [[airfoil]] to generate a reaction [[Lift (force)|lift]] from the moving fluid and impart it to the rotor. Wind turbines also gain some energy from the impulse of the wind, by deflecting it at an angle. Turbines with multiple stages may use either reaction or impulse blading at high pressure. Steam turbines were traditionally more impulse but continue to move towards reaction designs similar to those used in gas turbines. At low pressure the operating fluid medium expands in volume for small reductions in pressure.  Under these conditions, blading becomes strictly a reaction type design with the base of the blade solely impulse.  The reason is due to the effect of the rotation speed for each blade.  As the volume increases, the blade height increases, and the base of the blade spins at a slower speed relative to the tip.  This change in speed forces a designer to change from impulse at the base, to a high reaction-style tip.\n\nClassical turbine design methods were developed in the mid 19th century.  Vector analysis related the fluid flow with turbine shape and rotation. Graphical calculation methods were used at first. Formulae for the basic dimensions of turbine parts are well documented and a highly efficient machine can be reliably designed for any fluid [[flow conditioning|flow condition]]. Some of the calculations are empirical or 'rule of thumb' formulae, and others are based on [[classical mechanics]].  As with most engineering calculations, simplifying assumptions were made.\n\n[[File:Turbine inlet guide vanes of Atar turbojet.jpg|thumb|Turbine inlet guide vanes of a [[turbojet]]]]\n\n[[Velocity triangle]]s can be used to calculate the basic performance of a turbine stage. Gas exits the stationary turbine nozzle guide vanes at absolute velocity ''V''<sub>a1</sub>. The rotor rotates at velocity ''U''. Relative to the rotor, the velocity of the gas as it impinges on the rotor entrance is ''V''<sub>r1</sub>. The gas is turned by the rotor and exits, relative to the rotor, at velocity ''V''<sub>r2</sub>. However, in absolute terms the rotor exit velocity is ''V''<sub>a2</sub>. The velocity triangles are constructed using these various velocity vectors. Velocity triangles can be constructed at any section through the blading (for example: hub, tip, midsection and so on) but are usually shown at the mean stage radius. Mean performance for the stage can be calculated from the velocity triangles, at this radius, using the Euler equation:\n\n:<math>\\Delta h = u\\cdot\\Delta v_w</math>\n\nHence:\n\n:<math>\\frac{\\Delta h}{T} = \\frac{u\\cdot\\Delta v_w}{T}</math>\n\nwhere:\n\n:<math>\\Delta h</math> is the specific enthalpy drop across stage\n:<math>T</math> is the turbine entry total (or stagnation) temperature\n:<math>u</math> is the turbine rotor peripheral velocity\n:<math>\\Delta v_w</math> is the change in whirl velocity\n\nThe turbine pressure ratio is a function of <math>\\frac{\\Delta h}{T}</math> and the turbine efficiency.\n\nModern turbine design carries the calculations further.  [[Computational fluid dynamics]] dispenses with many of the simplifying assumptions used to derive classical formulas and computer software facilitates optimization. These tools have led to steady improvements in turbine design over the last forty years.\n\nThe primary numerical classification of a turbine is its [[specific speed]].  This number describes the speed of the turbine at its maximum efficiency with respect to the power and flow rate.  The specific speed is derived to be independent of turbine size. Given the fluid flow conditions and the desired shaft output speed, the specific speed can be calculated and an appropriate turbine design selected.\n\nThe specific speed, along with some fundamental formulas can be used to reliably scale an existing design of known performance to a new size with corresponding performance.\n\nOff-design performance is normally displayed as a [[turbine map]] or characteristic.\n\nThe number of blades in the rotor and the number of vanes in the stator are often two different [[prime number]]s in order to reduce the harmonics and maximize the blade-passing frequency.<ref>\nTim J Carter.\n[https://web.archive.org/web/20180517115019/http://opac.vimaru.edu.vn/edata/E-Journal/2005/Engineering%20failure%20analyis/12_2/12(2_4).pdf "Common failures in gas turbine blades"].\n2004.\np. 244-245.\n</ref>\n\n * [[Steam turbine]]s are used to drive electrical generators in thermal power plants which use [[coal]], [[fuel oil]] or [[nuclear fuel]].  They were once used to directly drive mechanical devices such as ships' [[propeller]]s (for example the ''[[Turbinia]]'', the first turbine-powered [[steam launch]],<ref>{{cite web|title=Turbinia|url=http://files.asme.org/ASMEORG/Communities/History/Landmarks/5652.pdf|work=(ASME-sponsored booklet to mark the designation of Turbinia as an international engineering landmark)|publisher=Tyne And Wear County Council Museums|access-date=13 April 2011|author=Adrian Osler|archive-url=https://web.archive.org/web/20110928063911/http://files.asme.org/ASMEORG/Communities/History/Landmarks/5652.pdf|archive-date=28 September 2011|date=October 1981|url-status=dead}}</ref>) but most such applications now use reduction gears or an intermediate electrical step, where the turbine is used to generate electricity, which then powers an [[electric motor]] connected to the mechanical load. Turbo electric ship machinery was particularly popular in the period immediately before and during [[World War II]], primarily due to a lack of sufficient gear-cutting facilities in US and UK shipyards.\n* Aircraft [[gas turbine]] engines are sometimes referred to as turbine engines to distinguish between piston engines.\n* [[Transonic]] turbine. The gas flow in most turbines employed in gas turbine engines remains subsonic throughout the expansion process. In a transonic turbine the gas flow becomes supersonic as it exits the nozzle guide vanes, although the downstream velocities normally become subsonic. Transonic turbines operate at a higher pressure ratio than normal but are usually less efficient and uncommon.\n* [[Contra-rotating]] turbines. With [[axial turbine]]s, some efficiency advantage can be obtained if a downstream turbine rotates in the opposite direction to an upstream unit. However, the complication can be counter-productive. A contra-rotating steam turbine, usually known as the Ljungstr\u00f6m turbine, was originally invented by Swedish Engineer [[Fredrik Ljungstr\u00f6m]] (1875\u20131964) in Stockholm, and in partnership with his brother Birger Ljungstr\u00f6m he obtained a patent in 1894. The design is essentially a multi-stage [[radial turbine]] (or pair of 'nested' turbine rotors) offering great efficiency, four times as large heat drop per stage as in the reaction (Parsons) turbine, extremely compact design and the type met particular success in back pressure power plants. However, contrary to other designs, large steam volumes are handled with difficulty and only a combination with axial flow turbines (DUREX) admits the turbine to be built for power greater than ca 50 MW. In marine applications only about 50 turbo-electric units were ordered (of which a considerable amount were finally sold to land plants) during 1917\u201319, and during 1920-22 a few turbo-mechanic not very successful units were sold.<ref>Ingvar Jung, 1979, The history of the marine turbine, part 1, Royal Institute of Technology, Stockholm, dep of History of technology</ref> Only a few turbo-electric marine plants were still in use in the late 1960s (ss Ragne, ss Regin) while most land plants remain in use 2010.\n* [[Stator]]less turbine. Multi-stage turbines have a set of static (meaning stationary) inlet guide vanes that direct the gas flow onto the rotating rotor blades. In a stator-less turbine the gas flow exiting an upstream rotor impinges onto a downstream rotor without an intermediate set of stator vanes (that rearrange the pressure/velocity energy levels of the flow) being encountered.\n* [[Ceramic]] turbine. Conventional high-pressure turbine blades (and vanes) are made from nickel based alloys and often use intricate internal air-cooling passages to prevent the metal from overheating. In recent years, experimental ceramic blades have been manufactured and tested in gas turbines, with a view to increasing rotor inlet temperatures and/or, possibly, eliminating air cooling. Ceramic blades are more brittle than their metallic counterparts, and carry a greater risk of catastrophic blade failure. This has tended to limit their use in jet engines and gas turbines to the stator (stationary) blades.\n* [[Ducted fan|Shrouded]] turbine. Many turbine rotor blades have shrouding at the top, which interlocks with that of adjacent blades, to increase damping and thereby reduce blade flutter. In large land-based electricity generation steam turbines, the shrouding is often complemented, especially in the long blades of a low-pressure turbine, with lacing wires. These wires pass through holes drilled in the blades at suitable distances from the blade root and are usually brazed to the blades at the point where they pass through. Lacing wires reduce blade flutter in the central part of the blades. The introduction of lacing wires substantially reduces the instances of blade failure in large or low-pressure turbines.\n* [[Ducted fan|Shroudless turbine]]. Modern practice is, wherever possible, to eliminate the rotor shrouding, thus reducing the [[Centrifugal force|centrifugal]] load on the blade and the cooling requirements.\n* [[Tesla turbine|Bladeless turbine]] uses the boundary layer effect and not a fluid impinging upon the blades as in a conventional turbine.\n[[File:Gfa 17 641006 2-0002 Turbinen.jpg|thumb|Three types of water turbines: Kaplan (in front), Pelton (middle) and Francis (back left)]]\n* [[Water turbine]]s\n** [[Pelton wheel|Pelton turbine]], a type of impulse water turbine.\n** [[Francis turbine]], a type of widely used water turbine.\n** [[Kaplan turbine]], a variation of the Francis Turbine.\n** [[Turgo turbine]], a modified form of the Pelton wheel.\n** [[Cross-flow turbine]], also known as Banki-Michell turbine, or Ossberger turbine.\n* [[Wind turbine]]. These normally operate as a single stage without nozzle and interstage guide vanes. An exception is the [[\u00c9olienne Boll\u00e9e]], which has a stator and a rotor.\n* Velocity compound "Curtis".  Curtis combined the de Laval and Parsons turbine by using a set of fixed nozzles on the first stage or stator and then a rank of fixed and rotating blade rows, as in the Parsons or de Laval, typically up to ten compared with up to a hundred stages of a Parsons design.  The overall efficiency of a Curtis design is less than that of either the Parsons or de Laval designs, but it can be satisfactorily operated through a much wider range of speeds, including successful operation at low speeds and at lower pressures, which made it ideal for use in ships' powerplant. In a Curtis arrangement, the entire heat drop in the steam takes place in the initial nozzle row and both the subsequent moving blade rows and stationary blade rows merely change the direction of the steam. Use of a small section of a Curtis arrangement, typically one nozzle section and two or three rows of moving blades, is usually termed a Curtis 'Wheel' and in this form, the Curtis found widespread use at sea as a 'governing stage' on many reaction and impulse turbines and turbine sets. This practice is still commonplace today in marine steam plant.\n* [[Pressure compounding in turbines|Pressure compound]] multi-stage impulse, or "Rateau", after its French inventor, [[:fr:Auguste Rateau|Auguste Rateau]].  The Rateau employs simple impulse rotors separated by a nozzle diaphragm. The diaphragm is essentially a partition wall in the turbine with a series of tunnels cut into it, funnel shaped with the broad end facing the previous stage and the narrow the next they are also angled to direct the steam jets onto the impulse rotor.\n*[[Mercury vapour turbine]]s used [[mercury (element)|mercury]] as the working fluid, to improve the efficiency of fossil-fuelled generating stations. Although a few power plants were built with combined mercury vapour and conventional steam turbines, the toxicity of the metal mercury was quickly apparent.\n*[[Screw turbine]] is a [[water turbine]] which uses the principle of the [[Archimedean screw]] to convert the [[potential energy]] of water on an upstream level into [[kinetic energy]].\n\n {{One source|section|date=May 2018}}\nA large proportion of the world's [[electrical power]] is generated by [[turbo generator]]s.\n\nTurbines are used in [[gas turbine]] engines on land, sea and air.\n\n[[Turbochargers]] are used on piston engines.\n\nGas turbines have very high power densities (i.e. the ratio of power to mass, or power to volume) because they run at very high speeds. The [[Space Shuttle main engine]]s used [[turbopump]]s (machines consisting of a pump driven by a turbine engine) to feed the propellants (liquid oxygen and liquid hydrogen) into the engine's combustion chamber.  The liquid hydrogen turbopump is slightly larger than an automobile engine (weighing approximately 700 lb) with the turbine producing nearly 70,000 [[horsepower|hp]] (52.2 [[megawatt|MW]]).\n\n[[Turboexpander]]s are used for refrigeration in industrial processes.\n\n {{Div col|small=yes}}\n* [[Balancing machine]]\n* [[Euler's pump and turbine equation]]\n* [[Helmholtz's theorems]]\n* [[Rotordynamics]]\n* [[Rotor\u2013stator interaction]]\n* [[Secondary flow]]\n* [[Segner wheel]]\n* [[Turbo-alternator]]\n* [[Turbodrill]]\n* [[Turbofan]]\n* [[Turbojet]]\n* [[Turboprop]]\n* [[Turboshaft]]\n* [[Turbine-electric transmission]]\n{{Div col end}}\n\n {{reflist|30em}}\n\n * Layton, Edwin T. "From Rule of Thumb to Scientific Engineering: James B. Francis and the Invention of the Francis Turbine," NLA Monograph Series. Stony Brook, NY:  Research Foundation of the State University of New York, 1992.\n\n {{commons category|Turbines (turbomachine component)|Turbine}}\n* [https://mysite.du.edu/~jcalvert/tech/fluids/turbine.htm Turbines]\n\n{{Authority control}}"}},
{"article_title": "TiVo", "pageid": "30936", "revid": "1062132799", "timestamp": "2021-12-26T14:19:26Z", "history_paths": [["TiVo --- Introduction ---", "History and development"]], "categories": ["tivo", "digital video recorders", "interactive television", "linux-based devices", "products introduced in 1999", "television terminology", "video storage", "television time shifting technology"], "heading_tree": {"TiVo --- Introduction ---": {"History and development": {}, "TiVo digital video recorder": {"Functions": {}, "Subscription service": {"Service availability": {"United Kingdom": {}}}, "Hardware anatomy": {}, "Drive expansion": {}, "Hacking": {}}, "TiVo in the cloud": {}, "Competitors and market share": {}, "Issues": {"Privacy concerns": {}, "Litigation": {}, "Opposition by content providers": {"Content flagging": {}, "Pop-up advertisements": {}}, "GNU General Public License and Tivoization": {}, "CableCard Support Uncertainty (USA)": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"TiVo --- Introduction ---|History and development": "TiVo was developed by Jim Barton and Mike Ramsay through a [[corporation]] they named "Teleworld" which was later renamed to [[TiVo Inc.]] Though they originally intended to create a home network device, it was redesigned as a device that records digitized video onto a hard disk. They began the first public trials of the TiVo device and service in late 1998 in the San Francisco Bay Area.\n\nAfter exhibiting at the Consumer Electronics Show in January 1999, Mike Ramsay announced to the company that the first version of the TiVo digital video recorder would ship "In Q1", (the last day of which is March 31) despite an estimated 4 to 5 months of work remaining to complete the device. Because March 31, 1999, was a [[blue moon]], the engineering staff code-named this first version of the TiVo DVR "Blue Moon".<ref>{{cite web |url=http://archive.tivocommunity.com/tivo-vb/showthread.php?s=&postid=429445 |title=The Second Greatest Story Ever Told: The 4th Annual Blue Moon Holiday - TiVo Community Forum Archive 1 |website=Archive.tivocommunity.com |access-date=October 16, 2012 |archive-url=https://web.archive.org/web/20110717062907/http://archive.tivocommunity.com/tivo-vb/showthread.php?s=&postid=429445 |archive-date=July 17, 2011 |url-status=dead }}</ref>\n\nThe original TiVo DVR digitized and compressed analog video from any source (antenna, cable or direct broadcast satellite). TiVo also integrates its DVR service into the set-top boxes of satellite and cable providers.  In late 2000, Philips Electronics introduced the DSR6000, the first DirecTV receiver with an integrated TiVo DVR. This new device, nicknamed the "DirecTiVo", stored digital signals sent from [[DirecTV]] directly onto a [[hard disk]].\n\nIn early 2000, TiVo partnered with electronics manufacturer Thomson Multimedia (now [[Technicolor SA]]) and broadcaster [[British Sky Broadcasting]] to deliver the TiVo service in the UK market. This partnership resulted in the Thomson PVR10UK, a stand-alone receiver released in October 2000 that was based on the original reference design used in the United States by both Philips and Sony. TiVo ended UK unit sales in January 2003, though it continued to sell subscriptions and supply guide data to existing subscribed units until June 2011. TiVo branded products returned to the UK during 2010 under an exclusive partnership with cable TV provider [[Virgin Media]].<ref name="Virgin Media Selects Tivo" />\n\nTiVo was launched in Australia in July 2008 by Hybrid Television Services, a company owned by Australia's Seven Media Group and New Zealand's TVNZ. TiVo Australia also launched a TiVo with a 320Gb hard Drive in 2009.<ref>{{cite web |url=http://www.mytivo.com.au/whatistivo/tivomodels/ |title=TiVo Models | What is TiVo |website=myTivo.com.au |access-date=October 16, 2012 |archive-url=https://web.archive.org/web/20120908030912/http://www.mytivo.com.au/whatistivo/tivomodels/ |archive-date=September 8, 2012 |url-status=dead }}</ref> TiVo Australia also launched [[Blockbuster Inc.|Blockbuster]] on demand and as of early December launched a novel service called Caspa on Demand.<ref>{{cite web |url=http://www.mytivo.com.au/whatistivo/moviestvmusic/entertainmentondemand/ |title=Entertainment On-Demand | Movies & TV On-Demand | What is TiVo |website=myTivo.com.au |access-date=October 16, 2012 |archive-url=https://web.archive.org/web/20121012095046/http://www.mytivo.com.au/whatistivo/moviestvmusic/entertainmentondemand/ |archive-date=October 12, 2012 |url-status=dead }}</ref>  TiVo also went on sale in New Zealand on 6 November 2009.<ref name="Sticking point for TiVo">{{cite news |url=http://www.stuff.co.nz/business/industries/2762085/Sticking-point-for-TiVo |title=Sticking point for TiVo |author=Pullar-Strecker, Tom |date=18 August 2009 |work=[[The Dominion Post (Wellington)|The Dominion Post]] |access-date=23 November 2011}}</ref>\n\n[[Janet Jackson]]'s [[Super Bowl XXXVIII halftime show controversy|Super Bowl halftime show incident]] on February 1, 2004, set a record for being the most watched, recorded and replayed moment in TiVo history. The baring of one of Jackson's breasts at the end of her duet with [[Justin Timberlake]], which caused a flood of outraged phone calls to [[CBS]], was replayed a record number of times by TiVo users. A company representative stated, "The audience measurement guys have never seen anything like it. The audience reaction charts looked like an [[electrocardiogram]]."<ref>{{cite web| title = Jackson's Super Bowl flash grabs TiVo users| website = CNET| date = 2004-02-04| url = http://news.cnet.com/2100-1041_3-5152141.html| access-date = 2013-06-18 }}</ref>\n\nIn April 2016, Rovi acquired TiVo for $1.1 billion.<ref name="Vincent 2016">{{cite web | last=Vincent | first=James | title=TiVo agrees to $1.1 billion acquisition by Rovi | website=The Verge | date=2016-04-29 | url=https://www.theverge.com/platform/amp/2016/4/29/11535490/rovi-tivo-acquisition-1-1-billion | access-date=2021-05-24}}</ref>\n\nIn December 2019, it was announced that TiVo would merge with Xperi Corporation. The merger completed in May 2020.<ref>{{cite web\n |url=https://www.businesswire.com/news/home/20200601005246/en/Xperi-and-TiVo-Complete-Merger#:~:text=TiVo%20common%20stock%20previously%20traded,no%20longer%20listed%20for%20trading.\n |title=Xperi and TiVo Complete Merger  |date=June 1, 2020 |publisher= businesswire |access-date=March 25, 2021}}</ref>"}},
{"article_title": "Time-sharing", "pageid": "30958", "revid": "1054766828", "timestamp": "2021-11-12T00:06:02Z", "history_paths": [["Time-sharing --- Introduction ---", "History"]], "categories": ["time-sharing", "operating system technology", "computer systems"], "heading_tree": {"Time-sharing --- Introduction ---": {"History": {"Batch processing": {}, "Time-sharing": {}, "Development": {}, "Time-sharing business": {"Rise and fall": {"Rapidata as an example": {}, "UK": {}}}, "The computer utility": {}, "Security": {}}, "Notable time-sharing systems": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Time-sharing --- Introduction ---|History": "{{Main|Batch processing}}\nThe earliest computers were extremely expensive devices, and very slow in comparison to later models. Machines were typically dedicated to a particular set of tasks and operated by control panels, the operator manually entering small programs via switches in order to load and run a series of programs. These programs might take hours to run. As computers grew in speed, [[Runtime (program lifecycle phase)|run times]] dropped, and soon the time taken to start up the next program became a concern. Newer [[batch processing]] software and methodologies decreased these "dead periods" by queuing up programs were developed: operating systems such as [[IBM 7090/94 IBSYS|IBSYS]] (1960).<ref>{{cite web |url=https://courses.cs.washington.edu/courses/cse451/16wi/readings/lecture_readings/LCM_OperatingSystemsTimeline_Color_acd_newsize.pdf |title=History of Operating Systems}}</ref>\n\nComparatively inexpensive [[card punch]] or [[paper tape]] writers were used by programmers to write their programs "offline". Programs were submitted to the operations team, which scheduled them to be run. Output (generally printed) was returned to the programmer. The complete process might take days, during which time the programmer might never see the computer.\n\nThe alternative of allowing the user to operate the computer directly was generally far too expensive to consider. This was because users might have long periods of entering code while the computer remained idle. This situation limited interactive development to those organizations that could afford to waste computing cycles: large universities for the most part. Stanford students made a short film humorously critiquing this situation.<ref>Eisenson, Arthur; and Yager, Heather (1967). Ellis D. Kropotchev Silent Film. Stanford University, 1967. Computer History Museum, Object ID 102695643. Retrieved on 2013-11-29 from http://www.computerhistory.org/revolution/punched-cards/2/211/2253.</ref>\n\n [[File:Unix Timesharing UW-Madison 1978.jpeg|thumb|[[Unix]] time-sharing at the [[University of Wisconsin]], 1978]]\nTime-sharing was developed out of the realization that while any single user would make inefficient use of a computer, a large group of users together would not. This was due to the pattern of interaction: Typically an individual user entered bursts of information followed by long pauses but a group of users working at the ''same time'' would mean that the pauses of one user would be filled by the activity of the others. Given an optimal group size, the overall process could be very efficient.  Similarly, small slices of time spent waiting for disk, tape, or network input could be granted to other users.\n\nThe concept is claimed to have been first described by [[John Backus]] in the 1954 summer session at MIT,<ref name="jbackus">Backus, John, ''[http://bitsavers.org/pdf/mit/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdf Computer Advanced Coding Techniques] {{Webarchive|url=https://web.archive.org/web/20180929021555/http://www.bitsavers.org/pdf/mit/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdf |date=2018-09-29 }}'', MIT 1954, page 16-2. The first known description of computer time-sharing.</ref> and later by [[Bob Bemer]] in his 1957 article "How to consider a computer" in ''Automatic Control Magazine''.<ref>{{cite web |last1=Bemer  |first1=Bob\n|title=Origins of Timesharing |url=http://www.bobbemer.com/TIMESHAR.HTM |website=bobbemer.com\n|date=March 1957 |access-date=June 24, 2016 |url-status = dead\n|archive-url = https://web.archive.org/web/20170702215126/http://www.bobbemer.com/TIMESHAR.HTM\n|archive-date = 2017-07-02}}</ref><ref>{{cite arXiv |last1=Middleburg |first1=C.A.\n|title=Searching Publications on Operating Systems |eprint=1003.5525 |class=cs.OS |year=2010}}</ref> In a paper published in December 1958 by W. F. Bauer,<ref name="wfbauer">Bauer, . ., ''[https://www.computer.org/web/csdl/index/-/csdl/proceedings/afips/1958/5053/00/50530046.pdf Computer design from the programmer's viewpoint] {{Webarchive|url=https://web.archive.org/web/20160723012920/https://www.computer.org/web/csdl/index/-/csdl/proceedings/afips/1958/5053/00/50530046.pdf |date=2016-07-23 }}'' (Eastern Joint Computer Conference, December 1958) One of the first descriptions of computer time-sharing.</ref> he wrote that "The computers would handle a number of problems concurrently. Organizations would have input-output equipment installed on their own premises and would buy time on the computer much the same way that the average household buys power and water from utility companies."\n\n[[Christopher Strachey]], who became Oxford University's first professor of computation, filed a patent application for "time-sharing" in February 1959.<ref>{{Cite web|title=Computer Pioneers - Christopher Strachey|url=https://history.computer.org/pioneers/strachey.html|access-date=2020-01-23|website=history.computer.org|quote=What Strachey proposed in his concept of time-sharing was an arrangement that would preserve the direct contact between programmer and machine, while still achieving the economy of multiprogramming.}}</ref><ref>{{Cite web|title=Computer - Time-sharing and minicomputers|url=https://www.britannica.com/technology/computer/Time-sharing-and-minicomputers|access-date=2020-01-23|website=Encyclopedia Britannica|language=en|quote=In 1959 Christopher Strachey in the United Kingdom and John McCarthy in the United States independently described something they called time-sharing.}}</ref> He gave a paper "Time Sharing in Large Fast Computers" at the first [[International Federation for Information Processing#History|UNESCO Information Processing Conference]] in Paris in June that year, where he passed the concept on to [[J. C. R. Licklider]].<ref>{{Cite book|last1=Gillies|first1=James M.|url=https://archive.org/details/howwebwasbornsto00gill/page/12/mode/2up?q=strachey|title=How the Web was Born: The Story of the World Wide Web|last2=Gillies|first2=James|last3=Gillies|first3=James|last4=Cailliau|first4=Robert|date=2000|publisher=Oxford University Press|isbn=978-0-19-286207-5|pages=13|language=en|url-access=registration}}</ref><ref>{{Cite web|title=Reminiscences on the Theory of Time-Sharing|url=http://jmc.stanford.edu/computing-science/timesharing.html|access-date=2020-01-23|website=jmc.stanford.edu|quote=in 1960 'time-sharing' as a phrase was much in the air.  It was, however, generally used in my sense rather than in John McCarthy's sense of a CTSS-like object.}}</ref> This paper is credited by the [[MIT Computation Center]] in 1963 as "the first paper on time-shared computers".<ref name="ctsspg">F. J. Corbat\u00f3, et al., ''[http://www.bitsavers.org/pdf/mit/ctss/CTSS_ProgrammersGuide.pdf The Compatible Time-Sharing System A Programmer's Guide]'' (MIT Press, 1963) {{ISBN|978-0-262-03008-3}}. "To establish the context of the present work, it is informative to trace the development of time-sharing at MIT. Shortly after the first paper on time-shared computers by C. Strachey at the June 1959 UNESCO Information Processing conference, H.M. Teager and J. McCarthy delivered an unpublished paper "Time-Shared Program Testing" at the August 1959 ACM Meeting."</ref>\n\nImplementing a system able to take advantage of this was initially difficult.<ref name=DECpro1/><ref>"There were no command files supported." - the commands to compile and then 'link' a program had to be typed in each time.  \tAs the article adds: "No CCL ([[Concise Command Language]])" referring to the DEC world's equivalent of [[Clist]] and [[Rexx]].</ref><ref name=JM>{{cite web|last1=McCarthy|first1=John|title=Reminiscences On the History of Time Sharing|url=http://www-formal.stanford.edu/jmc/history/timesharing/timesharing.html|website=stanford.edu|publisher=stanford.edu|access-date=12 March 2017|url-status=dead|archive-url=https://web.archive.org/web/20071020032705/http://www-formal.stanford.edu/jmc/history/timesharing/timesharing.html|archive-date=20 October 2007}}</ref>  Batch processing was effectively a methodological development on top of the earliest systems. Since computers still ran single programs for single users at any time, the primary change with batch processing was the time delay between one program and the next. Developing a system that supported multiple users at the same time was a completely different concept. The "state" of each user and their programs would have to be kept in the machine, and then switched between quickly. This would take up computer cycles, and on the slow machines of the era this was a concern. However, as computers rapidly improved in speed, and especially in size of [[Magnetic-core memory|core memory]] in which users' states were retained, the [[Overhead (computing)|overhead]] of time-sharing continually decreased, relatively speaking.\n\n<!-- Timesharing, per IBM's ad re the man sharing a $2 million machine (CALL/OS,360/50) doesn't fit this definition ....\nThe [[TX-2]] system at MIT, first reported in February 1957, provided general multitasking facilities for sharing the processor between a user program and [[device driver]]s.<ref>Forgie, James W. (1 April 1957) "The Lincoln TX-2 input-output system." In internal report, ''[http://www.bitsavers.org/pdf/mit/tx-2/TX-2_Papers_WJCC_57.pdf The Lincoln TX-2 Computer]''</ref> \nTEXT RETAINED in case need to provide more citations re above ad &/or definition ********** -->\nThe first project to implement time-sharing of user programs was initiated by [[John McCarthy (computer scientist)|John McCarthy]] at MIT in 1959, initially planned on a modified [[IBM 704]], and later on an additionally modified [[IBM 709]] (one of the first computers powerful enough for time-sharing).<ref name=JM/> One of the deliverables of the project, known as the ''[[Compatible Time-Sharing System]]'' or CTSS, was demonstrated in November 1961. CTSS has a good claim to be the first time-sharing system and remained in use until 1973. Another contender for the first demonstrated time-sharing system was [[PLATO (computer system)|PLATO]] II, created by [[Donald Bitzer]] at a public demonstration at [[Robert Allerton Park]] near the University of Illinois in early 1961. But this was a special-purpose system. Bitzer has long said that the PLATO project would have gotten the patent on time-sharing if only the University of Illinois had not lost the patent for two years.<ref>Brian Dear, Chapter 4 -- The Diagram, [https://books.google.com/books?id=D5ZBDwAAQBAJ&pg=PA71 The Friendly Orange Glow], Pantheon Books, New York, 2017; pages 71-72 discuss the development of time-sharing and the University of Illinois loss of the patent.</ref> [[JOSS]] began time-sharing service in January 1964.<ref>{{cite book | chapter=JOSS: a designer's view of an experimental on-line computing system | author = J. C. Shaw | title=Proceeding AFIPS '64 (Fall, part I) Proceedings of the October 27-29, 1964, fall joint computer conference, part I | year=1964 | pages=455\u2013464 | chapter-url=http://dl.acm.org/citation.cfm?id=1464093}}</ref>\n\nThe first commercially successful time-sharing system was the [[Dartmouth Time Sharing System]].<ref>dtss.dartmouth.edu/history.php</ref>\n\n Throughout the late 1960s and the 1970s, [[computer terminal]]s were multiplexed onto large institutional [[mainframe computer]]s ([[centralized computing]] systems), which in many implementations sequentially polled the terminals to see whether any additional data was available or action was requested by the computer user. Later technology in interconnections were [[interrupt]] driven, and some of these used parallel data transfer technologies such as the [[IEEE 488]] standard. Generally, computer terminals were utilized on college properties in much the same places as ''[[desktop computer]]s'' or ''[[personal computer]]s'' are found today. In the earliest days of personal computers, many were in fact used as particularly smart terminals for time-sharing systems.\n\nThe Dartmouth Time Sharing System's creators wrote in 1968 that "any response time which averages more than 10 seconds destroys the illusion of having one's own computer".<ref name="dtss196810">{{cite journal | url=http://dtss.dartmouth.edu/sciencearticle/index.html | title=Dartmouth Time-Sharing |author1=Kemeny, John G. |author2=Kurtz, Thomas E. | journal=Science | date=11 October 1968 | volume=162 | issue=3850 | pages=223\u2013228| doi=10.1126/science.162.3850.223 | pmid=5675464 }}</ref> Conversely, timesharing users thought that their terminal was the computer.<ref name="ncc1974">{{Cite web |url=http://dtss.dartmouth.edu/transcript.php |title=TRANSCRIPTS OF 1974 National Computer Conference Pioneer Day Session |website=Dartmouth Time Sharing System |publisher=Dartmouth College |year=1974}}</ref>\n\nWith the rise of microcomputing in the early 1980s, time-sharing became less significant, because individual microprocessors were sufficiently inexpensive that a single person could have all the [[CPU time]] dedicated solely to their needs, even when idle.\n\nHowever, the Internet brought the general concept of time-sharing back into popularity. Expensive corporate server farms costing millions can host thousands of customers all sharing the same common resources. As with the early serial terminals, web sites operate primarily in bursts of activity followed by periods of idle time. This bursting nature permits the service to be used by many customers at once, usually with no perceptible communication delays, unless the servers start to get very busy.\n\n '''Genesis'''\n\nIn the 1960s, several companies started providing time-sharing services as [[service bureau]]s. Early systems used [[Teletype Model 33]] KSR or ASR or Teletype Model 35 KSR or ASR machines in [[ASCII]] environments, and [[IBM Selectric typewriter]]-based terminals (especially the [[IBM 2741]]) with two different seven-bit codes.<ref>{{cite book\n |title=IBM 2741 Communication Terminal\n |publisher=IBM\n | page=12\n | url=http://www.textfiles.com/bitsavers/pdf/ibm/27xx/GA24-3415-3_2741_Data_Terminal_Aug72.pdf\n}}</ref> They would connect to the [[Centralized computing|central computer]] by [[dial-up]] Bell 103A modem or [[acoustic coupler|acoustically coupled]] [[modem]]s operating at 10–15 characters per second. Later terminals and modems supported 30–120 characters per second. The time-sharing system would provide a complete operating environment, including a variety of programming language processors, various software packages, file storage, bulk printing, and off-line storage. Users were charged rent for the terminal, a charge for hours of connect time, a charge for seconds of CPU time, and a charge for kilobyte-months of disk storage.\n\nCommon systems used for time-sharing included the [[SDS 940]], the [[PDP-10]], and the [[IBM 360]]. Companies providing this service included [[GE]]'s GEISCO, [[IBM]] subsidiary The [[Service Bureau Corporation]], [[Tymnet|Tymshare]] (founded in 1966), [[National CSS]] (founded in 1967 and bought by Dun & Bradstreet in 1979), Dial Data (bought by Tymshare in 1968), [[Bolt, Beranek, and Newman]] (BBN) and [[Time Sharing Limited | Time Sharing Ltd.]] in the [[United Kingdom|UK]]. By 1968, there were 32 such service bureaus serving the US [[National Institutes of Health]] (NIH) alone.<ref>"Information Technology Corporate Histories Collection". Computer History Museum. Retrieved on 2013-11-29 from http://www.computerhistory.org/corphist/view.php?s=stories&id=136.</ref> The ''Auerbach Guide to Timesharing'' (1973) lists 125 different timesharing services using equipment from [[Burroughs Corporation|Burroughs]], [[Control Data Corporation|CDC]], [[Digital Equipment Corporation|DEC]], [[Hewlett-Packard|HP]], [[Honeywell]], [[IBM]], [[RCA]], [[Univac]], and [[Scientific Data Systems|XDS]].<ref name=Auerbach>{{cite book|title=Auerbach Guide to Time Sharing|year=1973|publisher=Auerbach Publishers, Inc.|url=http://bitsavers.trailing-edge.com/pdf/auerbach/GuideToTimesharing_Jan73.pdf|access-date=2013-11-29}}</ref>\n\n In 1975, it was said about one of the major super-mini computer manufacturers<ref>Computerworld, June 11, 1975, p. 35</ref> that "The biggest end-user market currently is time-sharing." For DEC, for a while the second largest computer company (after IBM), this was also true: Their [[PDP-10]] and IBM's [[IBM System/360 Model 67|360/67]]<ref>One Two-page IBM print ad was headlined "100 or more people can use IBM's new time-sharing computer at the same time." Originals were/are? on e-Bay</ref>  were widely used<ref>p.1425, Encyclopedia of Computer Science, Litton Educational Publishing, Inc.</ref> by commercial timesharing services such as CompuServe, On-Line Systems (OLS), Rapidata and Time Sharing Ltd.\n\nThe advent of the [[personal computer]] marked the beginning of the decline of time-sharing. The economics were such that computer time went from being an expensive resource that had to be shared to being so cheap that computers could be left to sit idle for long periods in order to be available as needed.\n\n Although many time-sharing services simply closed, Rapidata<ref>https://groups.google.com/forum/#!topic/alt.folklore.computers/aE4TwORruB8 - "I worked for RapiData Timesharing for about a year circa 1969..."</ref><ref>someone else: "I worked there for almost 2 years 1977 to 1979." alt.folklore.computers/aE4TwORruB8/EdpKfFAlBncJ</ref> held on, and became part of [[National Data Corporation]].<ref>NDC started in 1967, and paralleled Rapidata; see Bloomberg's https://www.bloomberg.com/research/stocks/private/snapshot.asp?privcapId=290092</ref> It was still of sufficient interest in 1982 to be the focus of "A User's Guide to Statistics Programs: The Rapidata Timesharing System".<ref>Bruce Bosworth, {{ISBN|978-089529-1-677}}</ref>   Even as revenue fell by 66%<ref>''[[ComputerWorld]]'', Oct. 6, 1986, p.179, "Rapidata revenue was $11 million ... in 1986, down from ... ($31 million in 1982)."</ref> and National Data subsequently developed its own problems, attempts were made to keep this timesharing business going.<ref>Computerworld, Aug.25,1986, p.5,\n"National Data Corp. said it is close to reaching an agreement with a buyer of its Rapidata timesharing division. In May, National Data said it would close down ..."</ref><ref>National Data Corp became NDC-Health Corp in 2001 (bizjournals.com/atlanta/stories/2001/10/29/daily25.html)</ref><ref>As for a place in history, Rapidata is listed in 'The AUERBACH Guide to Time Sharing (1973)' http://bitsavers.informatik.uni-stuttgart.de/pdf/auerbach/GuideToTimesharing_Jan73.pdf</ref>\n\n * [[Time Sharing Limited]] (TSL, 1969-1974) - launched using DEC systems. [[PERT]] was one of its popular offerings. TSL was acquired by [[Automatic Data Processing|ADP]] in 1974.\n* OLS Computer Services (UK) Limited (1975-1980) - using HP & DEC systems.\n\n Beginning in 1964, the [[Multics]] operating system<ref>{{cite web |website=BitSavers\n    |url=http://www.bitsavers.org/pdf/honeywell/multics/AG92-06B_multicsCmds_Nov87.pdf\n    |title=Multics Commands and Active Functions (AG92-06) \n    |publisher=Honeywell Bull, Inc.  |date=February 1985\n    |access-date=January 10, 2021}}</ref> was designed as a [[computing utility]], modeled on the electrical or telephone utilities. In the 1970s, [[Ted Nelson]]'s original "[[Project Xanadu|Xanadu]]" hypertext repository was envisioned as such a service. It seemed as the computer industry grew that no such consolidation of computing resources would occur as timesharing systems. In the 1990s the concept was, however, revived in somewhat modified form under the banner of [[cloud computing]].\n\n Time-sharing was the first time that multiple [[Process (computing)|processes]], owned by different users, were running on a single machine, and these processes could interfere with one another.<ref name=Silberschatz2010>{{cite book|last1=Silberschatz |first1=Abraham| last2=Galvin |first2=Peter|last3=Gagne |first3=Greg|title=Operating system concepts|year=2010|publisher= Wiley & Sons | location = Hoboken, N.J. | isbn = 978-0-470-23399-3 | edition = 8th | page = 591}}</ref> For example, one process might alter [[shared resource]]s which another process relied on, such as a variable stored in memory. When only one user was using the system, this would result in possibly wrong output - but with multiple users, this might mean that other users got to see information they were not meant to see.\n\nTo prevent this from happening, an operating system needed to enforce a set of policies that determined which [[Privilege (computing)|privileges]] each process had. For example, the operating system might deny access to a certain variable by a certain process.\n\nThe first international conference on computer security in London in 1971 was primarily driven by the time-sharing industry and its customers.{{citation needed|date=December 2017}}"}},
{"article_title": "Thermometer", "pageid": "30993", "revid": "1058997721", "timestamp": "2021-12-06T20:43:44Z", "history_paths": [["Thermometer --- Introduction ---", "History"]], "categories": ["thermometers", "temperature", "meteorological instrumentation and equipment", "italian inventions", "dutch inventions", "17th-century inventions", "18th-century introductions", "science and technology in the dutch republic"], "heading_tree": {"Thermometer --- Introduction ---": {"History": {"Early developments": {}, "Era of precision thermometry": {}}, "Registering": {}, "Physical principles of thermometry": {"Thermometric materials": {}, "Constant volume thermometry": {}, "Radiometric thermometry": {}}, "Primary and secondary thermometers": {}, "Calibration": {}, "Precision, accuracy, and reproducibility": {}, "Indirect methods of temperature measurement": {}, "Applications": {"Nanothermometry": {}, "Cryometer": {}, "Medical": {}, "Food and food safety": {}, "Environmental": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Thermometer --- Introduction ---|History": "{{Main|Temperature|Temperature measurement}}\n[[File:1024 Pyrometer-8445.jpg|200px|thumbnail|An infrared thermometer is a kind of [[pyrometer]] ([[bolometer]]).]]\nWhile an individual thermometer is able to measure degrees of hotness, the readings on two thermometers cannot be compared unless they conform to an agreed scale. Today there is an absolute [[thermodynamic temperature]] scale. Internationally agreed temperature scales are designed to approximate this closely, based on fixed points and interpolating thermometers. The most recent official temperature scale is the [[International Temperature Scale of 1990]]. It extends from {{convert|0.65|K|C F|lk=in|1}} to approximately {{convert|1358|K|C F}}.\n\n[[File:Raumthermometer Fahrenheit+Celsius.jpg|thumb|right|180px|Thermometer with [[Fahrenheit]] (symbol \u00b0F) and [[Celsius]] (symbol \u00b0C) units.]]\n\n {{See also|Thermometry|Temperature scale|Thermoscope|Alcohol thermometer|Timeline of temperature and pressure measurement technology}}\n[[File:Termometri cinquantigradi inv 85 IF 46774.jpg|thumb|Fifty-degree thermometers from the mid-17th century on exhibit at the [[Museo Galileo]] with black dots representing single degrees and white represented 10-degree increments; used to measure atmospheric temperatures]]\nVarious authors have credited the invention of the thermometer to [[Hero of Alexandria]]. The thermometer was [[Timeline of temperature and pressure measurement technology|not a single invention, however, but a development]].\n[[Hero of Alexandria]] (10\u201370 AD) knew of the principle that certain substances, notably air, expand and contract and described a demonstration in which a closed tube partially filled with air had its end in a container of water.<ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'' {{ISBN|0-471-62767-4}}</ref> The expansion and contraction of the air caused the position of the water/air interface to move along the tube.\n\nSuch a mechanism was later used to show the hotness and coldness of the air with a tube in which the water level is controlled by the expansion and contraction of the gas. These devices were developed by several European scientists in the 16th and 17th centuries, notably [[Galileo Galilei]]<ref name=Doak>R.S. Doak (2005) Galileo: astronomer and physicist {{ISBN|0-7565-0813-4}} p36</ref> and [[Santorio Santorio]].<ref name=":0" /> As a result, devices were shown to produce this effect reliably, and the term ''thermoscope'' was adopted because it reflected the changes in [[sensible heat]] (the modern concept of temperature was yet to arise).<ref name=Doak/> The difference between a [[thermoscope]] and a thermometer is that the latter has a scale.<ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'' page 3, {{ISBN|0-471-62767-4}}</ref> Though Galileo is often said to be the inventor of the thermometer, there is no surviving document that he actually produced any such instrument.\n\nThe first clear diagram of a thermoscope was published in 1617 by [[Giuseppe Biancani]] (1566 \u2013 1624); the first showing a scale and thus constituting a thermometer was by [[Santorio Santorio]] in 1625.<ref name=":0" /> This was a vertical tube, closed by a bulb of air at the top, with the lower end opening into a vessel of water. The water level in the tube is controlled by the expansion and contraction of the air, so it is what we would now call an air thermometer.<ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'', pages 2\u20134 {{ISBN|0-471-62767-4}}</ref>\n\nThe word thermometer (in its French form) first appeared in 1624 in ''La R\u00e9cr\u00e9ation Math\u00e9matique'' by J. Leurechon, who describes one with a scale of 8 degrees.<ref name="page4">R.P. Benedict (1984) Fundamentals of Temperature, Pressure, and Flow Measurements, 3rd ed, {{ISBN|0-471-89383-8}} page 4</ref> The word comes from the [[Greek language|Greek]] words [[wikt:\u03b8\u03b5\u03c1\u03bc\u03cc\u03c2|\u03b8\u03b5\u03c1\u03bc\u03cc\u03c2]], ''thermos'', meaning "hot" and \u03bc\u03ad\u03c4\u03c1\u03bf\u03bd, ''metron'', meaning "measure".\n\nThe above instruments suffered from the disadvantage that they were also [[barometer]]s, i.e. sensitive to air pressure. In 1629, [[Joseph Solomon Delmedigo]], a student of Galileo and Santorio in Padua, published what is apparently the first description and illustration of a sealed liquid-in-glass thermometer.  It is described as having a bulb at the bottom of a sealed tube partially filled with brandy.  The tube had a numbered scale. Delmedigo did not claim to have invented this instrument. Nor did he name anyone else as its inventor.<ref>{{cite journal | last1 = Adler | first1 = Jacob | year = 1997 | title = J. S. Delmedigo and the Liquid-in-Glass Thermometer | journal = Annals of Science | volume = 54 | issue = 3| pages = 293\u2013299 | doi = 10.1080/00033799700200221 }}</ref> In about 1654, [[Ferdinando II de' Medici, Grand Duke of Tuscany]] (1610\u20131670) did produce such an instrument, the first modern-style thermometer, dependent on the expansion of a liquid and independent of air pressure.<ref name="page4" /> Many other scientists experimented with various liquids and designs of thermometer.\n\nHowever, each inventor and each thermometer was unique \u2014 there was [[Conversion of units of temperature|no standard scale]]. In 1665, [[Christiaan Huygens]] (1629\u20131695) suggested using the [[Melting point|melting]] and [[boiling point]]s of water as standards and, in 1694, Carlo Renaldini (1615\u20131698) proposed using them as fixed points on a universal scale. In 1701, [[Isaac Newton]] (1642\u20131726/27) proposed a scale of 12 degrees between the melting point of ice and [[Normal human body temperature|body temperature]].\n\n {{See also|Precision thermometry|Fahrenheit scale|Celsius scale|Mercury-in-glass thermometer|l4=Mercury-in-glass thermometer (mercury thermometer)|Medical thermometer|Clinical thermometer|Pyrometer|Infrared thermometer}}\n[[Image:Fahrenheit small.jpg|thumb|right|[[Daniel Gabriel Fahrenheit]], the originator of the era of [[precision thermometry]].<ref>Grigull, Ulrich (1966). ''Fahrenheit, a Pioneer of Exact Thermometry''. (The Proceedings of the 8th International Heat Transfer Conference, San Francisco, 1966, Vol. 1, pp. 9\u201318.)</ref> He invented the [[mercury-in-glass thermometer]] (first widely used, accurate, practical thermometer)<ref name="Knake">{{cite web|url=http://aashtoresource.org/university/newsletters/newsletters/2016/08/02/the-anatomy-of-a-liquid-in-glass-thermometer |author=Knake, Maria |title=The Anatomy of a Liquid-in-Glass Thermometer |publisher=AASHTO re:source, formerly AMRL (aashtoresource.org) |quote=For decades mercury thermometers were a mainstay in many testing laboratories. If used properly and [[Calibration|calibrated]] correctly, certain types of mercury thermometers can be incredibly accurate. Mercury thermometers can be used in temperatures ranging from about -38 to 350\u00b0C. The use of a mercury-[[thallium]] mixture can extend the low-temperature usability of mercury thermometers to -56\u00b0C. (...) Nevertheless, few liquids have been found to mimic the thermometric properties of mercury in [[repeatability]] and [[accuracy]] of [[temperature measurement]]. Toxic though it may be, when it comes to LiG [Liquid-in-Glass] thermometers, mercury is still hard to beat. |date=April 2011 |access-date=4 August 2018 }}</ref><ref name="AkashPeshin">{{cite web|url=https://www.scienceabc.com/innovation/why-is-mercury-used-in-thermometers.html |author=Peshin, Akash |title=Why mercury is used in thermometer? |publisher=Science ABC (scienceabc.com) |date=22 October 2019 |access-date=22 June 2020 }}</ref><ref name="SimpsonVictoria">{{cite web|url=https://www.worldatlas.com/articles/why-is-mercury-used-in-thermometers.html |author=Simpson, Victoria |title=Why is mercury used in thermometers? |publisher=WorldAtlas.com |date=21 May 2020 |access-date=21 June 2020 }}</ref> and [[Fahrenheit scale]] (first standardized temperature scale to be widely used).]]\n[[Image:Clinical thermometer 38.7.JPG|thumb|right|180px|A medical mercury-in-glass maximum thermometer.]]\n\nIn 1714, Dutch<ref name="Fahrenheit"/> scientist and inventor [[Daniel Gabriel Fahrenheit]] invented the first reliable thermometer, [[mercury thermometer|using mercury]] instead of [[alcohol thermometer|alcohol and water mixtures]]. In 1724, he proposed a [[temperature scale]] which now (slightly adjusted) [[Fahrenheit|bears his name]]. He could do this because he manufactured thermometers, using [[Mercury (element)|mercury]] (which has a high [[Thermal expansion|coefficient of expansion]]) for the first time, and the quality of his production could provide a finer scale and greater reproducibility, leading to its general adoption. <!--This is correct. The original scale was the "wrong" way round"-->In 1742, [[Anders Celsius]] (1701\u20131744) proposed a scale with zero at the boiling point and 100 degrees at the freezing point of water,<!--This is correct, originally 0 at boiling point, 100 at melting point, please do not switch these--><ref>R.P. Benedict (1984) Fundamentals of Temperature, Pressure, and Flow Measurements, 3rd ed, {{ISBN|0-471-89383-8}} page 6</ref> though the scale which now [[Celsius|bears his name]] has them the other way around.<ref>[http://www.sciencemuseum.org.uk/objects/heat/1951-581.aspx Christin's thermometer] {{webarchive|url=https://web.archive.org/web/20130601021835/http://www.sciencemuseum.org.uk/objects/heat/1951-581.aspx |date=2013-06-01 }} and [http://www.linnaeus.uu.se/online/life/6_32.html#bild2 Linnaeus' thermometer]</ref> French entomologist [[Ren\u00e9 Antoine Ferchault de R\u00e9aumur]] invented an alcohol thermometer and, [[R\u00e9aumur scale|temperature scale]] in 1730, that ultimately proved to be less reliable than Fahrenheit's mercury thermometer.\n\nThe first physician to use thermometer measurements in clinical practice was [[Herman Boerhaave]] (1668\u20131738).<ref>{{cite news |url=http://www.sma.org.sg/smj/4501/4501ms1.pdf |author-last1=Tan |author-first1=S. Y. |author-last2=Hu |author-first2=M |title=Medicine in Stamps: Hermann Boerhaave (1668 - 1738): 18th Century Teacher Extraordinaire |journal=Singapore Medical Journal |volume=45 |issue=1 |year=2004 |pages=3\u20135}}</ref> In 1866, Sir [[Thomas Clifford Allbutt]] (1836\u20131925) invented a [[Medical thermometer|clinical thermometer]] that produced a body temperature reading in five minutes as opposed to twenty.<ref name="Allbutt">[http://www.britannica.com/EBchecked/topic/16002/Sir-Thomas-Clifford-Allbutt Sir Thomas Clifford Allbutt], ''[[Encyclop\u00e6dia Britannica]]''</ref> In 1999, Dr. [[Francesco Pompei]] of the [[Exergen Corporation]] introduced the world's first temporal artery thermometer, a non-invasive temperature [[sensor]] which scans the forehead in about two seconds and provides a medically accurate body temperature.<ref>[http://www.exergen.com/about.htm Exergen Corporation]. Exergen.com. Retrieved on 2011-03-30.</ref><ref>[http://patents.justia.com/inventor/FRANCESCOPOMPEI.html Patents By Inventor Francesco Pompei :: Justia Patents]. Patents.justia.com. Retrieved on 2011-03-30.</ref>"}},
{"article_title": "Tokamak", "pageid": "31439", "revid": "1062434811", "timestamp": "2021-12-28T12:24:31Z", "history_paths": [["Tokamak --- Introduction ---", "History"]], "categories": ["science and technology in the soviet union", "soviet inventions", "tokamaks"], "heading_tree": {"Tokamak --- Introduction ---": {"Etymology": {}, "History": {"First steps": {}, "Lavrentiev's letter": {}, "Magnetic confinement": {}, "Richter and the birth of fusion research": {}, "New ideas": {}, "Instability": {}, "Steps toward declassification": {}, "First tokamaks": {}, "Atoms for Peace and the doldrums": {}, "Progress in the 1960s": {"Culham Five": {}, "US turmoil": {}, "Tokamak race in the US": {}}, "Heating: US takes the lead": {}, "1980s: great hope, great disappointment": {}, "ITER": {}}, "Design": {"Basic problem": {}, "Tokamak solution": {}, "Other issues": {}, "Breakeven, Q, and ignition": {}, "Advanced tokamaks": {}, "Plasma disruptions": {}}, "Plasma heating": {"Ohmic heating ~ inductive mode": {}, "Magnetic compression": {}, "Neutral-beam injection": {}, "Radio-frequency heating": {}}, "Particle inventory": {}, "Experimental tokamaks": {"Currently in operation": {}, "Previously operated": {}, "Planned": {}}, "See also": {}, "Notes": {}, "References": {"Citations": {}, "Bibliography": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Tokamak --- Introduction ---|History": "[[File:1987 CPA 5891.jpg|thumb|right|upright|A USSR stamp, 1987: Tokamak thermonuclear system]]\n\n In 1934, [[Mark Oliphant]], [[Paul Harteck]] and [[Ernest Rutherford]] were the first to achieve fusion on Earth, using a [[particle accelerator]] to shoot [[deuterium]] nuclei into metal foil containing deuterium or other atoms.<ref>{{cite journal |url=http://www.chemteam.info/Chem-History/Rutherford-1934b/Rutherford-1934b.html |title= Transmutation Effects Observed with Heavy Hydrogen |first=Mark |last1= Oliphant |first2=Paul |last2=Harteck |first3= Ernest |last3= Rutherford |journal= Proceedings of the Royal Society |volume=144 |issue= 853 |pages=692\u2013703 |date=1934 |doi=10.1098/rspa.1934.0077 |doi-access=free |bibcode= 1934RSPSA.144..692O }}</ref> This allowed them to measure the [[nuclear cross section]] of various fusion reactions, and determined that the deuterium\u2013deuterium reaction occurred at a lower energy than other reactions, peaking at about 100,000 [[electronvolt]]s (100 keV).{{sfn|McCracken|Stott|2012|p=35}}{{efn|D\u2013T fusion occurs at even lower energies, but [[tritium]] was unknown at the time. Their work created tritium, but they did not separate it chemically to demonstrate its existence. This was performed by [[Luis Walter Alvarez|Luis Alvarez]] and [[Robert Cornog]] in 1939.<ref>{{cite journal|doi=10.1103/PhysRev.56.613|title=Helium and Hydrogen of Mass 3|date=1939|last1=Alvarez|first1=Luis|last2=Cornog|first2=Robert|journal=Physical Review|volume=56|issue=6|pages=613|bibcode = 1939PhRv...56..613A }}</ref>}}\n\nAccelerator-based fusion is not practical because the reactor [[cross section (physics)|cross section]] is tiny; most of the particles in the accelerator will scatter off the fuel, not fuse with it. These scatterings cause the particles to lose energy to the point where they can no longer undergo fusion. The energy put into these particles is thus lost, and it is easy to demonstrate this is much more energy than the resulting fusion reactions can release.{{sfn|McCracken|Stott|2012|pp=36\u201338}}\n\nTo maintain fusion and produce net energy output, the bulk of the fuel must be raised to high temperatures so its atoms are constantly colliding at high speed; this gives rise to the name ''thermonuclear'' due to the high temperatures needed to bring it about. In 1944, [[Enrico Fermi]] calculated the reaction would be self-sustaining at about 50,000,000 K; at that temperature, the rate that energy is given off by the reactions is high enough that they heat the surrounding fuel rapidly enough to maintain the temperature against losses to the environment, continuing the reaction.{{sfn|McCracken|Stott|2012|pp=36\u201338}}\n\nDuring the [[Manhattan Project]], the first practical way to reach these temperatures was created, using an [[atomic bomb]]. In 1944, Fermi gave a talk on the physics of fusion in the context of a then-hypothetical [[hydrogen bomb]]. However, some thought had already been given to a ''controlled'' fusion device, and [[James L. Tuck]] and [[Stanislaw Ulam]] had attempted such using [[shaped charge]]s driving a metal foil infused with deuterium, although without success.{{sfn|Bromberg|1982|p=18}}\n\nThe first attempts to build a practical fusion machine took place in the [[United Kingdom]], where [[George Paget Thomson]] had selected the [[pinch effect]] as a promising technique in 1945. After several failed attempts to gain funding, he gave up and asked two graduate students, Stan Cousins and Alan Ware, to build a device out of surplus [[radar]] equipment. This was successfully operated in 1948, but showed no clear evidence of fusion and failed to gain the interest of the [[Atomic Energy Research Establishment]].{{sfn|Herman|1990|p=[https://archive.org/details/fusionsearchfore00herm/page/40 40]}}\n\n In 1950, [[Oleg Lavrentiev]], then a [[Red Army]] sergeant stationed on [[Sakhalin]] with little to do, wrote a letter to the [[Central Committee of the Communist Party of the Soviet Union]]. The letter outlined the idea of using an [[atomic bomb]] to ignite a fusion fuel, and then went on to describe a system that used [[electrostatic]] fields to contain a hot plasma in a steady state for energy production.{{sfn|Shafranov|2001|p=873}}<ref>{{cite journal |last= Bondarenko |first=B.D. |title= Role played by O. A. Lavrent'ev in the formulation of the problem and the initiation of research into controlled nuclear fusion in the USSR |journal= Phys. Usp. |volume=44 |issue=8 |page= 844 |date=2001 |url= http://ufn.ru/ufn01/ufn01_8/Russian/r018m.pdf|doi=10.1070/PU2001v044n08ABEH000910 }}</ref>{{efn|The system Lavrentiev described is very similar to the concept now known as the [[fusor]].}}\n\nThe letter was sent to [[Andrei Sakharov]] for comment. Sakharov noted that "the author formulates a very important and not necessarily hopeless problem", and found his main concern in the arrangement was that the plasma would hit the electrode wires, and that "wide meshes and a thin current-carrying part which will have to reflect almost all incident nuclei back into the reactor. In all likelihood, this requirement is incompatible with the mechanical strength of the device."{{sfn|Shafranov|2001|p=873}}\n\nSome indication of the importance given to Lavrentiev's letter can be seen in the speed with which it was processed; the letter was received by the Central Committee on 29 July, Sakharov sent his review in on 18 August, by October, Sakharov and [[Igor Tamm]] had completed the first detailed study of a fusion reactor, and they had asked for funding to build it in January 1951.{{sfn|Shafranov|2001|p=837}}\n\n When heated to fusion temperatures, the [[electron]]s in atoms disassociate, resulting in a fluid of nuclei and electrons known as a [[plasma (physics)|plasma]]. Unlike electrically neutral atoms, a plasma is electrically conductive, and can, therefore, be manipulated by electrical or magnetic fields.{{sfn|Bromberg|1982|p=15}}\n\nSakharov's concern about the electrodes led him to consider using magnetic confinement instead of electrostatic. In the case of a magnetic field, the particles will circle around the [[lines of force]].{{sfn|Bromberg|1982|p=15}} As the particles are moving at high speed, their resulting paths look like a helix. If one arranges a magnetic field so lines of force are parallel and close together, the particles orbiting adjacent lines may collide, and fuse.{{sfn|Shafranov|2001|p=838}}\n\nSuch a field can be created in a [[solenoid]], a cylinder with magnets wrapped around the outside. The combined fields of the magnets create a set of parallel magnetic lines running down the length of the cylinder. This arrangement prevents the particles from moving sideways to the wall of the cylinder, but it does not prevent them from running out the end. The obvious solution to this problem is to bend the cylinder around into a donut shape, or torus, so that the lines form a series of continual rings. In this arrangement, the particles circle endlessly.{{sfn|Shafranov|2001|p=838}}\n\nSakharov discussed the concept with [[Igor Tamm]], and by the end of October 1950 the two had written a proposal and sent it to [[Igor Kurchatov]], the director of the atomic bomb project within the USSR, and his deputy, [[Igor Golovin]].{{sfn|Shafranov|2001|p=838}} However, this initial proposal ignored a fundamental problem; when arranged along a straight solenoid, the external magnets are evenly spaced, but when bent around into a torus, they are closer together on the inside of the ring than the outside. This leads to uneven forces that cause the particles to drift away from their magnetic lines.{{sfn|Shafranov|2001|p=839}}{{sfn|Bromberg|1982|p=16}}\n\nDuring visits to the [[Laboratory of Measuring Instruments of the USSR Academy of Sciences]] (LIPAN), the Soviet nuclear research centre, Sakharov suggested two possible solutions to this problem. One was to suspend a current-carrying ring in the centre of the torus. The current in the ring would produce a magnetic field that would mix with the one from the magnets on the outside. The resulting field would be twisted into a helix, so that any given particle would find itself repeatedly on the outside, then inside, of the torus. The drifts caused by the uneven fields are in opposite directions on the inside and outside, so over the course of multiple orbits around the long axis of the torus, the opposite drifts would cancel out. Alternately, he suggested using an external magnet to induce a current in the plasma itself, instead of a separate metal ring, which would have the same effect.{{sfn|Shafranov|2001|p=839}}\n\nIn January 1951, Kurchatov arranged a meeting at LIPAN to consider Sakharov's concepts. They found widespread interest and support, and in February a report on the topic was forwarded to [[Lavrentiy Beria]], who oversaw the atomic efforts in the USSR. For a time, nothing was heard back.{{sfn|Shafranov|2001|p=839}}\n\n [[File:Ronald Richter y Per\u00f3n.jpg|thumb|upright=1.5|Ronald Richter (left) with [[Juan Domingo Per\u00f3n]] (right). Richter's claims sparked off fusion research around the world.]]\n\nOn 25 March 1951, Argentine President [[Juan Per\u00f3n]] announced that a former German scientist, [[Ronald Richter]], had succeeded in producing fusion at a laboratory scale as part of what is now known as the [[Huemul Project]]. Scientists around the world were excited by the announcement, but soon concluded it was not true; simple calculations showed that his experimental setup could not produce enough energy to heat the fusion fuel to the needed temperatures.<ref>{{cite news |first=Robert |last=Arnoux |title='Proyecto Huemul': the prank that started it all |url=https://www.iter.org/newsline/196/930 |website=iter |date=26 October 2011}}</ref>\n\nAlthough dismissed by nuclear researchers, the widespread news coverage meant politicians were suddenly aware of, and receptive to, fusion research. In the UK, Thomson, was suddenly granted considerable funding. Over the next months, two projects based on the pinch system were up and running.{{sfn|Bromberg|1982|p=75}} In the US, [[Lyman Spitzer]] read the Huemul story, realized it was false, and set about designing a machine that would work.{{sfn|Bromberg|1982|p=14}} In May he was awarded $50,000 to begin research on his [[stellarator]] concept.{{sfn|Bromberg|1982|p=21}} Jim Tuck had returned to the UK briefly and saw Thomson's pinch machines. When he returned to Los Alamos he also received $50,000 directly from the Los Alamos budget.{{sfn|Bromberg|1982|p=25}}\n\nSimilar events occurred in the USSR. In mid-April, Dmitri Efremov of the Scientific Research Institute of Electrophysical Apparatus stormed into Kurchatov's study with a magazine containing a story about Richter's work, demanding to know why they were beaten by the Argentines. Kurchatov immediately contacted Beria with a proposal to set up a separate fusion research laboratory with [[Lev Artsimovich]] as director. Only days later, on 5 May, the proposal had been signed by [[Joseph Stalin]].{{sfn|Shafranov|2001|p=839}}\n\n [[File:EAST_Tokamak_plasma_image3.jpg|thumb|Red plasma in EAST]]\nBy October, Sakharov and Tamm had completed a much more detailed consideration of their original proposal, calling for a device with a major radius (of the torus as a whole) of {{convert|12|m}} and a minor radius (the interior of the cylinder) of {{convert|2|m}}. The proposal suggested the system could produce {{convert|100|g}} of [[tritium]] a day, or breed {{convert|10|kg}} of U233 a day.{{sfn|Shafranov|2001|p=839}}\n\nAs the idea was further developed, it was realized that a current in the plasma could create a field that was strong enough to confine the plasma as well, removing the need for the external magnets.{{sfn|Shafranov|2001|p=840}} At this point, the Soviet researchers had re-invented the pinch system being developed in the UK,{{sfn|Bromberg|1982|p=18}} although they had come to this design from a very different starting point.\n\nOnce the idea of using the pinch effect for confinement had been proposed, a much simpler solution became evident. Instead of a large toroid, one could simply induce the current into a linear tube, which could cause the plasma within to collapse down into a filament. This had a huge advantage; the current in the plasma would heat it through normal [[resistive heating]], but this would not heat the plasma to fusion temperatures. However, as the plasma collapsed, the [[adiabatic process]] would result in the temperature rising dramatically, more than enough for fusion. With this development, only Golovin and [[Natan Yavlinsky]] continued considering the more static toroidal arrangement.{{sfn|Shafranov|2001|p=840}}\n\n On 4 July 1952, [[Nikolai Filippov]]'s group measured [[neutron]]s being released from a linear pinch machine. [[Lev Artsimovich]] demanded that they check everything before concluding fusion had occurred, and during these checks, they found that the neutrons were not from fusion at all.{{sfn|Shafranov|2001|p=840}} This same linear arrangement had also occurred to researchers in the UK and US, and their machines showed the same behaviour. But the great secrecy surrounding the type of research meant that none of the groups were aware that others were also working on it, let alone having the identical problem.<ref name=master>{{cite magazine |first=John |last=Adams |title=Can we master the thermonuclear plasma? |date=31 January 1963 |magazine=New Scientist | url=https://books.google.com/books?id=TF7wQYDRIXAC&pg=PA222 |pages=222\u2013225}}</ref>\n\nAfter much study, it was found that some of the released neutrons were produced by instabilities in the plasma. There were two common types of instability, the ''sausage'' that was seen primarily in linear machines, and the ''kink'' which was most common in the toroidal machines.<ref name=master/> Groups in all three countries began studying the formation of these instabilities and potential ways to address them.<ref name=criterion>{{cite web |url=http://home.physics.ucla.edu/calendar/conferences/cmpd/talks/cowley.pdf |title=Introduction to Kink Modes \u2013 the Kruskal- Shafranov Limit |first=Steve |last=Cowley |website=UCLA}}</ref> Important contributions to the field were made by [[Martin David Kruskal]] and [[Martin Schwarzschild]] in the US, and Shafranov in the USSR.{{sfn|Kadomtsev|1966}}\n\nOne idea that came from these studies became known as the "stabilized pinch". This concept added additional magnets to the outside of the chamber, which created a field that would be present in the plasma before the pinch discharge. In most concepts, the external field was relatively weak, and because a plasma is [[diamagnetic]], it penetrated only the outer areas of the plasma.<ref name=master/> When the pinch discharge occurred and the plasma quickly contracted, this field became "frozen in" to the resulting filament, creating a strong field in its outer layers. In the US, this was known as "giving the plasma a backbone."{{sfn|Clery|2014|p=48}}\n\nSakharov revisited his original toroidal concepts and came to a slightly different conclusion about how to stabilize the plasma. The layout would be the same as the stabilized pinch concept, but the role of the two fields would be reversed. Instead of weak external fields providing stabilization and a strong pinch current responsible for confinement, in the new layout, the external magnets would be much more powerful in order to provide the majority of confinement, while the current would be much smaller and responsible for the stabilizing effect.{{sfn|Shafranov|2001|p=840}}\n\n [[File:Kurchatov at Harwell on 26 April 1956.jpg|thumb|Khrushchev (roughly centred, bald), Kurchatov (to the right, bearded), and Bulganin (to the right, white-haired) visited Harwell on 26 April 1956. Cockcroft stands across from them (in glasses), while a presenter points to mockups of various materials being tested in the newly opened [[DIDO (nuclear reactor)|DIDO reactor]].]]\n\nIn 1955, with the linear approaches still subject to instability, the first toroidal device was built in the USSR. TMP was a classic pinch machine, similar to models in the UK and US of the same era. The vacuum chamber was made of ceramic, and the spectra of the discharges showed silica, meaning the plasma was not perfectly confined by magnetic field and hitting the walls of the chamber.{{sfn|Shafranov|2001|p=840}} Two smaller machines followed, using copper shells.<ref name=tokomag/> The conductive shells were intended to help stabilize the plasma, but were not completely successful in any of the machines that tried it.{{sfn|Bromberg|1982|p=70}}\n\nWith progress apparently stalled, in 1955, Kurchatov called an All Union conference of Soviet researchers with the ultimate aim of opening up fusion research within the USSR.{{sfn|Shafranov|2001|p=240}} In April 1956, Kurchatov travelled to the UK as part of a widely publicized visit by [[Nikita Khrushchev]] and [[Nikolai Bulganin]]. He offered to give a talk at Atomic Energy Research Establishment, at the former [[RAF Harwell]], where he shocked the hosts by presenting a detailed historical overview of the Soviet fusion efforts.{{sfn|Shafranov|2001|p=841}} He took time to note, in particular, the neutrons seen in early machines and warned that neutrons did not mean fusion.<ref>{{cite speech |title=The possibility of producing thermonuclear reactions in a gaseous discharge |url=https://www.iter.org/doc/www/content/com/Lists/Mag%20Stories/Attachments/64/kurchatov_1956.pdf |date=26 April 1956 |first=Igor |last=Kurchatov |location=UKAEA Harwell}}</ref>\n\nUnknown to Kurchatov, the British [[ZETA (fusion reactor)|ZETA]] stabilized pinch machine was being built at the far end of the former runway. ZETA was, by far, the largest and most powerful fusion machine to date. Supported by experiments on earlier designs that had been modified to include stabilization, ZETA intended to produce low levels of fusion reactions. This was apparently a great success, and in January 1958, they announced the fusion had been achieved in ZETA based on the release of neutrons and measurements of the plasma temperature.{{sfn|McCracken|Stott|2012|p=5}}\n\n[[Vitaly Shafranov]] and Stanislav Braginskii examined the news reports and attempted to figure out how it worked. One possibility they considered was the use of weak "frozen in" fields, but rejected this, believing the fields would not last long enough. They then concluded ZETA was essentially identical to the devices they had been studying, with strong external fields.{{sfn|Shafranov|2001|p=841}}\n\n By this time, Soviet researchers had decided to build a larger toroidal machine along the lines suggested by Sakharov. In particular, their design considered one important point found in Kruskal's and Shafranov's works; if the helical path of the particles made them circulate around the plasma's circumference more rapidly than they circulated the long axis of the torus, the kink instability would be strongly suppressed.<ref name=criterion/>\n\nToday this basic concept is known as the ''[[Safety factor (plasma physics)|safety factor]]''. The ratio of the number of times the particle orbits the major axis compared to the minor axis is denoted ''q'', and the ''Kruskal-Shafranov Limit'' stated that the kink will be suppressed as long as ''q'' > 1. This path is controlled by the relative strengths of the external magnets compared to the field created by the internal current. To have ''q'' > 1, the external magnets must be much more powerful, or alternatively, the internal current has to be reduced.<ref name=criterion/>\n\nFollowing this criterion, design began on a new reactor, T-1, which today is known as the first real tokamak.<ref name=tokomag/> T-1 used both stronger external magnets and a reduced current compared to stabilized pinch machines like ZETA. The success of the T-1 resulted in its recognition as the first working tokamak.<ref name=autogenerated1/>{{sfn|Shafranov|2001}}<ref>[http://vant.iterru.ru/vant_2012_1/naj.pdf \u041a \u0441\u0442\u043e\u043b\u0435\u0442\u0438\u044e \u0441\u043e \u0434\u043d\u044f \u0440\u043e\u0436\u0434\u0435\u043d\u0438\u044f \u041d. \u0410. \u042f\u0432\u043b\u0438\u043d\u0441\u043a\u043e\u0433\u043e]</ref><ref>[http://ufn.ru/ufn01/ufn01_8/Russian/r018l.pdf \u0412. \u0414. \u0428\u0430\u0444\u0440\u0430\u043d\u043e\u0432 \u00ab\u041a \u0438\u0441\u0442\u043e\u0440\u0438\u0438 \u0438\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u043d\u0438\u0439 \u043f\u043e \u0443\u043f\u0440\u0430\u0432\u043b\u044f\u0435\u043c\u043e\u043c\u0443 \u0442\u0435\u0440\u043c\u043e\u044f\u0434\u0435\u0440\u043d\u043e\u043c\u0443 \u0441\u0438\u043d\u0442\u0435\u0437\u0443\u00bb]</ref>\nFor his work on "powerful impulse discharges in a gas, to obtain unusually high temperatures needed for thermonuclear processes", Yavlinskii was awarded the [[Lenin Prize]] and the [[State Stalin Prize|Stalin Prize]] in 1958. Yavlinskii was already preparing the design of an even larger model, later built as T-3. With the apparently successful ZETA announcement, Yavlinskii's concept was viewed very favourably.{{sfn|Shafranov|2001|p=841}}<ref>{{cite web |title=\u041e\u0422\u0426\u042b \u0418 \u0414\u0415\u0414\u042b \u0422\u0415\u0420\u041c\u041e\u042f\u0414\u0415\u0420\u041d\u041e\u0419 \u042d\u041f\u041e\u0425\u0418 |url=http://www.ras.ru/digest/showdnews.aspx?id=578d7525-c224-4f92-9a57-ed7113cb2c75&print=1 |access-date=6 November 2018}}</ref>\n\nDetails of ZETA became public in a series of articles in ''Nature'' later in January. To Shafranov's surprise, the system did use the "frozen in" field concept.{{sfn|Shafranov|2001|p=841}} He remained sceptical, but a team at the [[Ioffe Institute]] in [[St. Petersberg]] began plans to build a similar machine known as Alpha. Only a few months later, in May, the ZETA team issued a release stating they had not achieved fusion, and that they had been misled by erroneous measures of the plasma temperature.{{sfn|Herman|1990|p=53}}\n\nT-1 began operation at the end of 1958.{{sfn|Smirnov|2009|p=2}}{{efn|Although one source says "late 1957".<ref name=tokomag/>}} It demonstrated very high energy losses through radiation. This was traced to impurities in the plasma due to the vacuum system causing outgassing from the container materials. In order to explore solutions to this problem, another small device was constructed, T-2. This used an internal liner of corrugated metal that was baked at {{convert|550|C}} to cook off trapped gasses.{{sfn|Smirnov|2009|p=2}}\n\n As part of the second [[Atoms for Peace]] meeting in [[Geneva]] in September 1958, the Soviet delegation released many papers covering their fusion research. Among them was a set of initial results on their toroidal machines, which at that point had shown nothing of note.{{sfn|Shafranov|2001|p=842}}\n\nThe "star" of the show was a large model of Spitzer's stellarator, which immediately caught the attention of the Soviets. In contrast to their designs, the stellarator produced the required twisted paths in the plasma without driving a current through it, using a series of magnets that could operate in the steady state rather than the pulses of the induction system. Kurchatov began asking Yavlinskii to change their T-3 design to a stellarator, but they convinced him that the current provided a useful second role in heating, something the stellarator lacked.{{sfn|Shafranov|2001|p=842}}\n\nAt the time of the show, the stellarator had suffered a long string of minor problems that were just being solved. Solving these revealed that the diffusion rate of the plasma was much faster than theory predicted. Similar problems were seen in all the contemporary designs, for one reason or another. The stellarator, various pinch concepts and the [[magnetic mirror]] machines in both the US and USSR all demonstrated problems that limited their confinement times.{{sfn |Smirnov|2009|p=2}}\n\nFrom the first studies of controlled fusion, there was a problem lurking in the background. During the Manhattan Project, [[David Bohm]] had been part of the team working on isotopic separation of [[uranium]]. In the post-war era he continued working with plasmas in magnetic fields. Using basic theory, one would expect the plasma to diffuse across the lines of force at a rate inversely proportional to the square of the strength of the field, meaning that small increases in force would greatly improve confinement. But based on their experiments, Bohm developed an empirical formula, now known as [[Bohm diffusion]], that suggested the rate was linear with the magnetic force, not its square.{{sfn|Bromberg|1982|p=66}}\n\nIf Bohm's formula was correct, there was no hope one could build a fusion reactor based on magnetic confinement. To confine the plasma at the temperatures needed for fusion, the magnetic field would have to be orders of magnitude greater than any known magnet. Spitzer ascribed the difference between the Bohm and classical diffusion rates to turbulence in the plasma,<ref>{{Cite journal | last1 = Spitzer | first1 = L. | title = Particle Diffusion across a Magnetic Field | doi = 10.1063/1.1706104 | journal = Physics of Fluids | volume = 3 | issue = 4 | page = 659| year = 1960 |bibcode = 1960PhFl....3..659S }}</ref> and believed the steady fields of the stellarator would not suffer from this problem. Various experiments at that time suggested the Bohm rate did not apply, and that the classical formula was correct.{{sfn|Bromberg|1982|p=66}}\n\nBut by the early 1960s, with all of the various designs leaking plasma at a prodigious rate, Spitzer himself concluded that the Bohm scaling was an inherent quality of plasmas, and that magnetic confinement would not work.{{sfn|Smirnov|2009|p=2}} The entire field descended into what became known as "the doldrums",{{sfn|Bromberg|1982|p=130}} a period of intense pessimism.{{sfn|Shafranov|2001|p=840}}\n\n In contrast to the other designs, the experimental tokamaks appeared to be progressing well, so well that a minor theoretical problem was now a real concern. In the presence of gravity, there is a small pressure gradient in the plasma, formerly small enough to ignore but now becoming something that had to be addressed. This led to the addition of yet another set of magnets in 1962, which produced a vertical field that offset these effects. These were a success, and by the mid-1960s the machines began to show signs that they were beating the [[Bohm diffusion|Bohm limit]].{{sfn|Bromberg|1982|p=153}}\n\nAt the 1965 Second [[International Atomic Energy Agency]] Conference on fusion at the UK's newly opened [[Culham Centre for Fusion Energy]], Artsimovich reported that their systems were surpassing the Bohm limit by 10 times. Spitzer, reviewing the presentations, suggested that the Bohm limit may still apply; the results were within the range of experimental error of results seen on the stellarators, and the temperature measurements, based on the magnetic fields, were simply not trustworthy.{{sfn|Bromberg|1982|p=153}}\n\nThe next major international fusion meeting was held in August 1968 in [[Novosibirsk]]. By this time two additional tokamak designs had been completed, TM-2 in 1965, and T-4 in 1968. Results from T-3 had continued to improve, and similar results were coming from early tests of the new reactors. At the meeting, the Soviet delegation announced that T-3 was producing electron temperatures of 1000 eV (equivalent to 10 million degrees Celsius) and that confinement time was at least 50 times the Bohm limit.{{sfn|Bromberg|1982|p=151}}\n\nThese results were at least 10 times that of any other machine. If correct, they represented an enormous leap for the fusion community. Spitzer remained sceptical, noting that the temperature measurements were still based on the indirect calculations from the magnetic properties of the plasma. Many concluded they were due to an effect known as [[runaway electrons]], and that the Soviets were measuring only those extremely energetic electrons and not the bulk temperature. The Soviets countered with several arguments suggesting the temperature they were measuring was [[Maxwell\u2013Boltzmann distribution|Maxwellian]], and the debate raged.{{sfn|Bromberg|1982|p=166}}\n\n In the aftermath of ZETA, the UK teams began the development of new plasma diagnostic tools to provide more accurate measurements. Among these was the use of a [[laser]] to directly measure the temperature of the bulk electrons using [[Thomson scattering]]. This technique was well known and respected in the fusion community;{{sfn|Bromberg|1982|p=172}} Artsimovich had publicly called it "brilliant". Artsimovich invited [[Bas Pease]], the head of Culham, to use their devices on the Soviet reactors. At the height of the [[cold war]], in what is still considered a major political manoeuvre on Artsimovich's part, British physicists were allowed to visit the Kurchatov Institute, the heart of the Soviet nuclear bomb effort.<ref>{{cite web |url=https://www.walesonline.co.uk/news/wales-news/valleys-boy-who-broached-iron-1794244 |title= The Valleys boy who broached the Iron Curtain to convince the USA that Russian Cold War nuclear fusion claims were true |date=3 November 2011 |website=WalesOnline}}</ref>\n\nThe British team, nicknamed "The Culham Five",<ref>{{cite magazine |first=Robert |last=Arnoux |url=http://www.iter.org/newsline/102/1401 |title=Off to Russia with a thermometer |magazine=ITER Newsline |issue=102 |date=9 October 2009}}</ref> arrived late in 1968. After a lengthy installation and calibration process, the team measured the temperatures over a period of many experimental runs. Initial results were available by August 1969; the Soviets were correct, their results were accurate. The team phoned the results home to Culham, who then passed them along in a confidential phone call to Washington.{{sfn|Bromberg|1982|p=167}} The final results were published in ''Nature'' in November 1969.<ref name=culham>{{cite journal |first1=N. J. |last1=Peacock |first2=D. C. |last2=Robinson |first3=M. J. |last3=Forrest |first4=P. D. |last4=Wilcock |first5=V. V. |last5=Sannikov |s2cid=4290094 |title=Measurement of the Electron Temperature by Thomson Scattering in Tokamak T3 |journal=[[Nature (journal)|Nature]] |volume=224 |issue=5218 |pages=488\u2013490 |year=1969 |doi=10.1038/224488a0 |bibcode=1969Natur.224..488P }}</ref> The results of this announcement have been described as a "veritable stampede" of tokamak construction around the world.<ref>{{cite magazine |magazine=New Scientist |title=Fusion research - the temperature rises |first=Michael |last=Kenward |url=https://books.google.com/books?id=tbhTdnZsqMUC&pg=PA626 |date=24 May 1979}}</ref>\n\nOne serious problem remained. Because the electrical current in the plasma was much lower and produced much less compression than a pinch machine, this meant the temperature of the plasma was limited to the resistive heating rate of the current. First proposed in 1950, [[Spitzer resistivity]] stated that the [[electrical resistance]] of a plasma was reduced as the temperature increased,<ref name="Spitzer 1950">{{cite journal\n |last1=Cohen |first1=Robert S.\n |last2=Spitzer, Jr. |first2=Lyman\n |last3=McR. Routly |first3=Paul\n |title=The Electrical Conductivity of an Ionized Gas\n |date=October 1950\n |journal=Physical Review \n |volume=80\n |issue=2\n |pages=230\u2013238\n |url=http://ayuba.fr/pdf/spitzer1950.pdf\n |doi=10.1103/PhysRev.80.230\n|bibcode=1950PhRv...80..230C}}</ref> meaning the heating rate of the plasma would slow as the devices improved and temperatures were pressed higher. Calculations demonstrated that the resulting maximum temperatures while staying within ''q'' > 1 would be limited to the low millions of degrees. Artsimovich had been quick to point this out in Novosibirsk, stating that future progress would require new heating methods to be developed.{{sfn|Bromberg|1982|p=161}}\n\n One of the people attending the Novosibirsk meeting in 1968 was [[Amasa Stone Bishop]], one of the leaders of the US fusion program. One of the few other devices to show clear evidence of beating the Bohm limit at that time was the [[multipole (fusion reactor)|multipole]] concept. Both [[Lawrence Livermore National Laboratory|Lawrence Livermore]] and the [[Princeton Plasma Physics Laboratory]] (PPPL), home of Spitzer's stellarator, were building variations on the multipole design. While moderately successful on their own, T-3 greatly outperformed either machine. Bishop was concerned that the multipoles were redundant and thought the US should consider a tokamak of its own.{{sfn|Bromberg|1982|p=152}}\n\nWhen he raised the issue at a December 1968 meeting, directors of the labs refused to consider it. [[Melvin B. Gottlieb]] of Princeton was exasperated, asking "Do you think that this committee can out-think the scientists?"{{sfn|Bromberg|1982|p=154}} With the major labs demanding they control their own research, one lab found itself left out. [[Oak Ridge National Laboratory|Oak Ridge]] had originally entered the fusion field with studies for reactor fueling systems, but branched out into a mirror program of their own. By the mid-1960s, their DCX designs were running out of ideas, offering nothing that the similar program at the more prestigious and politically powerful Livermore didn't. This made them highly receptive to new concepts.{{sfn|Bromberg|1982|p=158}}\n\nAfter a considerable internal debate, [[Herman Postma]] formed a small group in early 1969 to consider the tokamak.{{sfn|Bromberg|1982|p=158}} They came up with a new design, later christened [[Ormak (fusion reactor)|Ormak]], that had several novel features. Primary among them was the way the external field was created in a single large copper block, fed power from a large [[transformer]] below the torus. This was as opposed to traditional designs that used magnet windings on the outside. They felt the single block would produce a much more uniform field. It would also have the advantage of allowing the torus to have a smaller major radius, lacking the need to route cables through the donut hole, leading to a lower ''[[aspect ratio]]'', which the Soviets had already suggested would produce better results.{{sfn|Bromberg|1982|p=159}}\n\n In early 1969, Artsimovich visited [[Massachusetts Institute of Technology|MIT]], where he was hounded by those interested in fusion. He finally agreed to give several lectures in April{{sfn|Bromberg|1982|p=161}} and then allowed lengthy question-and-answer sessions. As these went on, MIT itself grew interested in the tokamak, having previously stayed out of the fusion field for a variety of reasons. [[Bruno Coppi]] was at MIT at the time, and following the same concepts as Postma's team, came up with his own low-aspect-ratio concept, [[Alcator]]. Instead of Ormak's toroidal transformer, Alcator used traditional ring-shaped magnets but required them to be much smaller than existing designs. MIT's [[Francis Bitter Magnet Laboratory]] was the world leader in magnet design and they were confident they could build them.{{sfn|Bromberg|1982|p=161}}\n\nDuring 1969, two additional groups entered the field. At [[General Atomics]], [[Tihiro Ohkawa]] had been developing multipole reactors, and submitted a concept based on these ideas. This was a tokamak that would have a non-circular plasma cross-section; the same math that suggested a lower aspect-ratio would improve performance also suggested that a C or D-shaped plasma would do the same. He called the new design [[Doublet (fusion reactor)|Doublet]].{{sfn|Bromberg|1982|p=164}} Meanwhile, a group at [[University of Texas at Austin]] was proposing a relatively simple tokamak to explore heating the plasma through deliberately induced turbulence, the [[Texas Turbulent Tokamak]].{{sfn|Bromberg|1982|p=165}}\n\nWhen the members of the Atomic Energy Commissions' Fusion Steering Committee met again in June 1969, they had "tokamak proposals coming out of our ears."{{sfn|Bromberg|1982|p=165}} The only major lab working on a toroidal design that was not proposing a tokamak was Princeton, who refused to consider it in spite of their Model C stellarator being just about perfect for such a conversion. They continued to offer a long list of reasons why the Model C should not be converted. When these were questioned, a furious debate broke out about whether the Soviet results were reliable.{{sfn|Bromberg|1982|p=165}}\n\nWatching the debate take place, Gottlieb had a change of heart. There was no point moving forward with the tokamak if the Soviet electron temperature measurements were not accurate, so he formulated a plan to either prove or disprove their results. While swimming in the pool during the lunch break, he told [[Harold Furth]] his plan, to which Furth replied: "well, maybe you're right."{{sfn|Bromberg|1982|p=167}} After lunch, the various teams presented their designs, at which point Gottlieb presented his idea for a "stellarator-tokamak" based on the Model C.{{sfn|Bromberg|1982|p=167}}\n\nThe Standing Committee noted that this system could be complete in six months, while Ormak would take a year.{{sfn|Bromberg|1982|p=167}} It was only a short time later that the confidential results from the Culham Five were released. When they met again in October, the Standing Committee released funding for all of these proposals. The Model C's new configuration, soon named [[Symmetrical Tokamak]], intended to simply verify the Soviet results, while the others would explore ways to go well beyond T-3.{{sfn|Bromberg|1982|p=168}}\n\n [[File:Princeton Large Torus 1975.jpg|thumb|upright=1.5|Overhead view of the Princeton Large Torus in 1975. PLT set numerous records and demonstrated that the temperatures needed for fusion were possible.]]\n\nExperiments on the Symmetric Tokamak began in May 1970, and by early the next year they had confirmed the Soviet results and then surpassed them. The stellarator was abandoned, and PPPL turned its considerable expertise to the problem of heating the plasma. Two concepts seemed to hold promise. PPPL proposed using magnetic compression, a pinch-like technique to compress a warm plasma to raise its temperature, but providing that compression through magnets rather than current.{{sfn|Bromberg|1982|p=169}} Oak Ridge suggested [[neutral beam injection]], small particle accelerators that would shoot fuel atoms through the surrounding magnetic field where they would collide with the plasma and heat it.{{sfn|Bromberg|1982|p=171}}\n\nPPPL's [[Adiabatic Toroidal Compressor]] (ATC) began operation in May 1972, followed shortly thereafter by a neutral-beam equipped Ormak. Both demonstrated significant problems, but PPPL leapt past Oak Ridge by fitting beam injectors to ATC and provided clear evidence of successful heating in 1973. This success "scooped" Oak Ridge, who fell from favour within the Washington Steering Committee.{{sfn|Bromberg|1982|p=212}}\n\nBy this time a much larger design based on beam heating was under construction, the [[Princeton Large Torus]], or PLT. PLT was designed specifically to "give a clear indication whether the tokamak concept plus auxiliary heating can form a basis for a future fusion reactor".<ref name=timeline>{{cite web |title=Timeline |website=PPPL |url=https://www.pppl.gov/about/history/timeline}}</ref> PLT was an enormous success, continually raising its internal temperature until it hit 60 million Celsius (8,000 eV, eight times T-3's record) in 1978. This is a key point in the development of the tokamak; fusion reactions become self-sustaining at temperatures between 50 and 100 million Celsius, PLT demonstrated that this was technically achievable.<ref name=timeline/>\n\nThese experiments, especially PLT, put the US far in the lead in tokamak research. This is due largely to budget; a tokamak cost about $500,000 and the US annual fusion budget was around $25 million at that time.{{sfn|Bromberg|1982|p=151}} They could afford to explore all of the promising methods of heating, ultimately discovering neutral beams to be among the most effective.{{sfn|Bromberg|1982|p=173}}\n\nDuring this period, [[Robert L. Hirsch|Robert Hirsch]] took over the Directorate of fusion development in the [[U.S. Atomic Energy Commission]]. Hirsch felt that the program could not be sustained at its current funding levels without demonstrating tangible results. He began to reformulate the entire program. What had once been a lab-led effort of mostly scientific exploration was now a Washington-led effort to build a working power-producing reactor.{{sfn|Bromberg|1982|p=173}} This was given a boost by the [[1973 oil crisis]], which led to greatly increased research into [[alternative energy]] systems.{{sfn|Bromberg|1982|p=175}}\n\n [[File:The JET magnetic fusion experiment in 1991.jpg|thumb|upright=1.5|The [[Joint European Torus]] (JET), the largest currently operating tokamak, which has been in operation since 1983]]\n\nBy the late-1970s, tokamaks had reached all the conditions needed for a practical fusion reactor; in 1978 PLT had demonstrated ignition temperatures, the next year the Soviet T-7 successfully used [[superconducting]] magnets for the first time,{{sfn|Smirnov|2009|p=5}} Doublet proved to be a success and led to almost all future designs adopting this "shaped plasma" approach. It appeared all that was needed to build a power-producing reactor was to put all of these design concepts into a single machine, one that would be capable of running with the radioactive [[tritium]] in its fuel mix.{{sfn|Bromberg|1982|p=10}}\n\nThe race was on. During the 1970s, four major second-generation proposals were funded worldwide. The Soviets continued their development lineage with the T-15,{{sfn|Smirnov|2009|p=5}} while a pan-European effort was developing the [[Joint European Torus]] (JET) and Japan began the [[JT-60]] effort (originally known as the "Breakeven Plasma Test Facility"). In the US, Hirsch began formulating plans for a similar design, skipping over proposals for another stepping-stone design directly to a tritium-burning one. This emerged as the [[Tokamak Fusion Test Reactor]] (TFTR), run directly from Washington and not linked to any specific lab.{{sfn|Bromberg|1982|p=10}} Originally favouring Oak Ridge as the host, Hirsch moved it to PPPL after others convinced him they would work the hardest on it because they had the most to lose.{{sfn|Bromberg|1982|p=215}}\n\nThe excitement was so widespread that several commercial ventures to produce commercial tokamaks began around this time. Best known among these, in 1978, [[Bob Guccione]], publisher of [[Penthouse Magazine]], met [[Robert Bussard]] and became the world's biggest and most committed private investor in fusion technology, ultimately putting $20 million of his own money into Bussard's Compact Tokamak. Funding by the [[Riggs Bank]] led to this effort being known as the [[Riggatron]].<ref>{{cite web |first=Robert |last=Arnoux |url=https://www.iter.org/newsline/151/468 |title=Penthouse founder had invested his fortune in fusion |website=ITER |date=25 October 2010}}</ref>\n\nTFTR won the construction race and began operation in 1982, followed shortly by JET in 1983 and JT-60 in 1985. JET quickly took the lead in critical experiments, moving from test gases to deuterium and increasingly powerful "shots". But it soon became clear that none of the new systems were working as expected. A host of new instabilities appeared, along with a number of more practical problems that continued to interfere with their performance. On top of this, dangerous "excursions" of the plasma hitting with the walls of the reactor were evident in both TFTR and JET. Even when working perfectly, plasma confinement at fusion temperatures, the so-called "[[fusion triple product]]", continued to be far below what would be needed for a practical reactor design.\n\nThrough the mid-1980s the reasons for many of these problems became clear, and various solutions were offered. However, these would significantly increase the size and complexity of the machines. A follow-on design incorporating these changes would be both enormous and vastly more expensive than either JET or TFTR. A new period of pessimism descended on the fusion field.\n\n {{Main|ITER}}\n[[File:U.S. Department of Energy - Science - 425 003 001 (9786811206).jpg|thumb|upright=1.5|Cutaway diagram of the [[International Thermonuclear Experimental Reactor]] (ITER) the largest tokamak in the world, which began construction in 2013 and is projected to begin full operation in 2035. It is intended as a demonstration that a practical [[fusion reactor]] is possible, and will produce 500 megawatts of power. Blue human figure at bottom shows scale.]]\n\nAt the same time these experiments were demonstrating problems, much of the impetus for the US's massive funding disappeared; in 1986 [[Ronald Reagan]] declared the [[1970s energy crisis]] was over,<ref>{{cite web |url=http://www.presidency.ucsb.edu/ws/index.php?pid=37156 |title=Radio Address to the Nation on Oil Prices |first=Ronald |last=Reagan |date=19 April 1986 |website=The American Presidency Project}}</ref> and funding for advanced energy sources had been slashed in the early 1980s.\n\nSome thought of an international reactor design had been ongoing since June 1973 under the name INTOR, for INternational TOkamak Reactor. This was originally started through an agreement between [[Richard Nixon]] and [[Leonid Brezhnev]], but had been moving slowly since its first real meeting on 23 November 1978.<ref>{{cite web |url=https://www.iter.org/newsline/62/146 |title=INTOR: The international fusion reactor that never was |date=15 December 2008 |first=Robert |last=Arnoux |website=ITER}}</ref>\n\nDuring the [[Geneva Summit (1985)|Geneva Summit]] in November 1985, Reagan raised the issue with [[Mikhail Gorbachev]] and proposed reforming the organization. "... The two leaders emphasized the potential importance of the work aimed at utilizing controlled thermonuclear fusion for peaceful purposes and, in this connection, advocated the widest practicable development of international cooperation in obtaining this source of energy, which is essentially inexhaustible, for the benefit for all mankind."<ref>[http://www.reagan.utexas.edu/archives/speeches/1985/112185a.htm Joint Soviet-United States Statement on the Summit Meeting in Geneva] Ronald Reagan. 21 November 1985</ref>\n\nThe next year, an agreement was signed between the US, Soviet Union, European Union and Japan, creating the [[International Thermonuclear Experimental Reactor]] organization.<ref>{{cite journal|author=Educational Foundation for Nuclear Science, Inc. |title=Bulletin of the Atomic Scientists |journal=Bulletin of the Atomic Scientists : Science and Public Affairs |url=https://archive.org/details/bub_gb_wQwAAAAAMBAJ |date=October 1992 |publisher=Educational Foundation for Nuclear Science, Inc. |pages=[https://archive.org/details/bub_gb_wQwAAAAAMBAJ/page/n10 9]\u2013 |issn=0096-3402}}</ref>{{sfn|Braams|Stott|2002|pp=[https://books.google.com/books?id=Zj4vx9O0T0YC&pg=PA250 250\u2013]}}\n\nDesign work began in 1988, and since that time the ITER reactor has been the primary tokamak design effort worldwide."}},
{"article_title": "Virtual machine", "pageid": "32353", "revid": "1040095210", "timestamp": "2021-08-22T16:27:46Z", "history_paths": [["Virtual machine --- Introduction ---", "History"]], "categories": ["virtual machines", "operating system technology", "programming language implementation"], "heading_tree": {"Virtual machine --- Introduction ---": {"Definitions": {"System virtual machines": {}, "Process virtual machines": {}}, "History": {}, "Full virtualization": {"Hardware-assisted virtualization": {}}, "Operating-system-level virtualization": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Virtual machine --- Introduction ---|History": "{{See also|History of CP/CMS|timeline of virtualization development}}\n{{More citations needed section|date=July 2015}}\n\nBoth system virtual machines and process virtual machines date to the 1960s and continue to be areas of active development.\n\n''System virtual machines'' grew out of [[time-sharing]], as notably implemented in the [[Compatible Time-Sharing System]] (CTSS). Time-sharing allowed multiple users to use a computer [[Concurrent computing|concurrently]]: each program appeared to have full access to the machine, but only one program was executed at the time, with the system switching between programs in time slices, saving and restoring state each time. This evolved into virtual machines, notably via IBM's research systems: the [[IBM M44/44X|M44/44X]], which used [[partial virtualization]], and the [[IBM CP-40|CP-40]] and [[SIMMON]], which used [[full virtualization]], and were early examples of [[hypervisor]]s. The first widely available virtual machine architecture was the [[CP-67]]/CMS (see [[History of CP/CMS]] for details). An important distinction was between using multiple virtual machines on one host system for time-sharing, as in M44/44X and CP-40, and using one virtual machine on a host system for prototyping, as in SIMMON. [[Emulator]]s, with hardware emulation of earlier systems for compatibility, date back to the [[IBM System/360]] in 1963,<ref name="Pugh_1995"/><ref name="Pugh_1991"/> while the software emulation (then-called "simulation") predates it.\n\n''Process virtual machines'' arose originally as abstract platforms for an [[intermediate language]] used as the [[intermediate representation]] of a program by a [[compiler]]; early examples date to around 1966. An early 1966 example was the [[O-code machine]], a virtual machine that executes [[O-code]] (object code) emitted by the [[Compiler#Front end|front end]] of the [[BCPL]] compiler. This abstraction allowed the compiler to be easily ported to a new architecture by implementing a new [[Compiler#Back end|back end]] that took the existing O-code and compiled it to machine code for the underlying physical machine. The [[Euler (programming language)|Euler]] language used a similar design, with the intermediate language named ''P'' (portable).<ref name="Wirth_1966"/> This was popularized around 1970 by [[Pascal (programming language)|Pascal]], notably in the [[Pascal-P]] system (1973) and [[Pascal-S]] compiler (1975), in which it was termed [[p-code machine|p-code]] and the resulting machine as a [[p-code machine]]. This has been influential, and virtual machines in this sense have been often generally called p-code machines. In addition to being an intermediate language, Pascal p-code was also executed directly by an interpreter implementing the virtual machine, notably in [[UCSD Pascal]] (1978); this influenced later interpreters, notably the [[Java virtual machine]] (JVM). Another early example was [[SNOBOL4]] (1967), which was written in the SNOBOL Implementation Language (SIL), an assembly language for a virtual machine, which was then targeted to physical machines by transpiling to their native assembler via a [[macro assembler]].<ref name="Griswold_1972"/> Macros have since fallen out of favor, however, so this approach has been less influential. Process virtual machines were a popular approach to implementing early microcomputer software, including [[Tiny BASIC#Implementation in a virtual machine|Tiny BASIC]] and adventure games, from one-off implementations such as [[Pyramid 2000]] to a general-purpose engine like [[Infocom]]'s [[z-machine]], which [[Graham Nelson]] argues is "possibly the most portable virtual machine ever created".<ref name="inform-interpreters"/>\n\nSignificant advances occurred in the implementation of [[Smalltalk]]-80,<ref name="Goldberg_1983"/>\nparticularly the Deutsch/Schiffmann implementation<ref name="Deutsch_1984"/>\nwhich pushed [[just-in-time compilation|just-in-time (JIT) compilation]] forward as an implementation approach that uses process virtual machine.<ref name="Aycock_2003"/>\nLater notable Smalltalk VMs were [[VisualWorks]], the [[Squeak Virtual Machine]],<ref name="Ingalls_1997"/>\nand [[Strongtalk]].<ref name="Griswold_1993"/>\nA related language that produced a lot of virtual machine innovation was the [[Self (programming language)|Self]] programming language,<ref name="Ungar_1987"/> which pioneered [[adaptive optimization]]<ref name="Hoelzle"/> and [[Tracing garbage collection#Generational GC (ephemeral GC)|generational garbage collection]]. These techniques proved commercially successful in 1999 in the [[HotSpot (virtual machine)|HotSpot]] Java virtual machine.<ref name="Paleczny_2001"/>\nOther innovations include having a register-based virtual machine, to better match the underlying hardware, rather than a stack-based virtual machine, which is a closer match for the programming language; in 1995, this was pioneered by the [[Dis virtual machine]] for the [[Limbo (programming language)|Limbo]] language. OpenJ9 is an alternative for HotSpot JVM in OpenJDK and is an open source eclipse project claiming better startup and less resource consumption compared to HotSpot."}},
{"article_title": "Vaccination", "pageid": "32473", "revid": "1060039910", "timestamp": "2021-12-13T03:10:01Z", "history_paths": [["Vaccination --- Introduction ---", "History"]], "categories": ["vaccination", "biotechnology"], "heading_tree": {"Vaccination --- Introduction ---": {"Mechanism of function": {"Vaccination versus inoculation": {}, "Preventing disease versus preventing infection": {}}, "Safety": {"Vaccine development and approval": {}, "Side effects": {}, "Ingredients": {"Aluminium": {}, "Mercury": {}}, "Monitoring": {}}, "Usage": {"United States": {}}, "History": {}, "Vaccination policy": {"Fractional dose vaccination": {}, "Efficient distribution of vaccinations": {}, "Litigation": {}, "Opposition": {"Vaccination and autism": {}}}, "Routes of administration": {}, "Economics of vaccination": {"Costs and benefits": {}}, "Gallery": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Vaccination --- Introduction ---|History": "{{Further|Inoculation#Origins}}\n[[File:Edward Jenner, testimonial to the efficacy of vaccination. Wellcome L0020705.jpg|thumb|upright|left|An 1802 testimonial to the efficacy of vaccination, presented to its pioneer, [[Edward Jenner]], and signed by 112 members of the [[Physical Society of London|Physical Society, London]].]]\n\nBefore the first vaccinations, in the sense of using [[cowpox]] to inoculate people against [[smallpox]], people have been inoculated in China and elsewhere, before being copied in [[Western world|the west]], by using smallpox, called [[variolation]]. The earliest hints of the practice of variolation for smallpox in China come during the 10th century.<ref name="needham volume 6 part 6 154">{{cite book| vauthors = Needham J |title=Science and Civilisation in China: Volume 6, Biology and Biological Technology, Part 6, Medicine|publisher=Cambridge University Press|year=2000|isbn=9780521632621|page=154}}</ref> The Chinese also practiced the oldest documented use of variolation, which comes from [[Wan Quan]]'s (1499\u20131582) Douzhen Xinfa (\u75d8\u75b9\u5fc3\u6cd5) of 1549. They implemented a method of "nasal [[Insufflation (medicine)|insufflation]]" administered by blowing powdered smallpox material, usually scabs, up the nostrils. Various insufflation techniques have been recorded throughout the sixteenth and seventeenth centuries within China.<ref name="Williams2010">{{cite book| vauthors = Williams G |title=Angel of Death|publisher=Palgrave Macmillan|year=2010|isbn=978-0-230-27471-6|location=Basingstoke c}}</ref>{{rp|60}} Two reports on the Chinese practice of [[inoculation]] were received by the [[Royal Society]] in London in 1700; one by [[Martin Lister]] who received a report by an employee of the [[East India Company]] stationed in China and another by [[Clopton Havers]].<ref>{{cite book| vauthors = Silverstein AM |title=A History of Immunology|publisher=Academic Press|year=2009|isbn=9780080919461|edition=2nd|page=293}}</ref> In France, [[Voltaire]] reports that the Chinese have practiced variolation "these hundred years".\n\nIn 1796, [[Edward Jenner]], a doctor in [[Berkeley, Gloucestershire|Berkeley]] in [[Gloucestershire]], England, tested a common theory that a person who had contracted cowpox would be immune from smallpox. To test the theory, he took cowpox [[Vesicle (dermatology)|vesicle]]s from a [[milkmaid]] named Sarah Nelmes with which he infected an eight-year-old boy named [[James Phipps]], and two months later he inoculated the boy with smallpox, and smallpox did not develop. In 1798, Jenner published ''An Inquiry into the Causes and Effects of the Variolae Vacciniae'' which created widespread interest. He distinguished 'true' and 'spurious' cowpox (which did not give the desired effect) and developed an "arm-to-arm" method of propagating the vaccine from the vaccinated individual's [[Skin condition|pustule]]. Early attempts at confirmation were confounded by contamination with smallpox, but despite controversy within the medical profession and religious opposition to the use of animal material, by 1801 his report was translated into six languages and over 100,000 people were vaccinated.<ref name="GrossSepkowitz">{{cite journal | vauthors = Gross CP, Sepkowitz KA | title = The myth of the medical breakthrough: smallpox, vaccination, and Jenner reconsidered | journal = International Journal of Infectious Diseases | volume = 3 | issue = 1 | pages = 54\u201360 | date = July 1998 | pmid = 9831677 | doi = 10.1016/s1201-9712(98)90096-0 | doi-access = free }}</ref> The term ''vaccination'' was coined in 1800 by the surgeon Richard Dunning in his text ''Some observations on vaccination''.<ref>{{Cite web | vauthors = Dunning R | date = 1800 | publisher = March and Teape |url=https://curiosity.lib.harvard.edu/contagion/catalog/36-990061255320203941 |title=Some observations on vaccination, or, The inoculated cow-pox; Some observations on vaccination; Inoculated cow-pox; Observations, & c; Observations, &c|website=Contagion \u2013 CURIOSity Digital Collections|language=en|access-date=2 April 2020}}</ref>\n\nIn 1802, the [[Scotland|Scottish]] physician [[Helenus Scott]] vaccinated dozens of children in [[Bombay]] against smallpox using Jenner's cowpox vaccine.<ref>{{cite book| vauthors = Foege WH |title=House on Fire: The Fight to Eradicate Smallpox|url=https://books.google.com/books?id=ZunWRQ5_2TAC&pg=PA92|year=2011|publisher=University of California Press|isbn=978-0-520-26836-4|page=92}}</ref> In the same year Scott penned a letter to the editor in the ''[[Bombay Courier]]'', declaring that "We have it now in our power to communicate the benefits of this important discovery to every part of India, perhaps to China and the whole eastern world".<ref name = "Bennett_2016">{{cite book|title=The War Against Smallpox: Edward Jenner and the Global Spread of Vaccination | vauthors = Bennett M |publisher= Cambridge University Press|year=2016|isbn=9780521765671 }}</ref>{{rp|243}} Subsequently, vaccination became firmly established in [[British India]]. A vaccination campaign was started in the new British colony of [[Ceylon]] in 1803. By 1807 the British had vaccinated more than a million Indians and [[Sri Lankans]] against smallpox.<ref name = "Bennett_2016" />{{rp|244}} Also in 1803 the Spanish [[Balmis Expedition]] launched the first transcontinental effort to vaccinate people against smallpox.<ref>{{Cite web|date=2021-07-27|title=Exhibition tells story of Spanish children used as vaccine fridges in 1803|url=http://www.theguardian.com/world/2021/jul/27/spanish-museum-celebrates-pioneer-who-took-smallpox-vaccine-to-colonies|access-date=2021-07-31|website=the Guardian|language=en}}</ref>  Following a smallpox epidemic in 1816 the [[Kingdom of Nepal]] ordered smallpox vaccine and requested the English veterinarian [[William Moorcroft (explorer)|William Moorcroft]] to help in launching a vaccination campaign.<ref name = "Bennett_2016" />{{rp|265\u2013266}} In the same year a law was passed in Sweden to require the vaccination of children against smallpox by the age of two. [[Prussia]] briefly introduced compulsory vaccination in 1810 and again in the 1920s, but decided against a compulsory vaccination law in 1829. A law on compulsory smallpox vaccination was introduced in the [[Province of Hanover]] in the 1820s. In 1826, in [[Kragujevac]], future prince Mihailo of [[Serbia]] was the first person to be vaccinated against smallpox in the principality of Serbia.<ref>{{Cite web|url=https://www.kragujevacke.rs/DRUSTVO/ISTORIJA-VAKCINACIJA-U-SRBIJI/|title=Prvo vakcinisanje u Kragujevcu}}</ref> Following a smallpox epidemic in 1837 that caused 40,000 deaths, the [[British government]] initiated a concentrated [[vaccination policy]], starting with the [[Vaccination Act]] of 1840, which provided for universal vaccination and prohibited [[variolation]].<ref name = "Bennett_2016" />{{rp|365}} The Vaccination Act 1853 introduced compulsory smallpox vaccination in England and Wales.<ref name = "Brunton_2008">{{Cite book|title=The Politics of Vaccination: Practice and Policy in England, Wales, Ireland, and Scotland, 1800-1874 | vauthors = Brunton D |publisher=University Rochester Press|year=2008|isbn=9781580460361}}</ref>{{rp|39}} The law followed a severe outbreak of smallpox in 1851 and 1852. It provided that the [[poor law]] authorities would continue to dispense vaccination to all free of charge, but that records were to be kept on vaccinated children by the network of births registrars.<ref name = "Brunton_2008" />{{rp|41}} It was accepted at the time, that voluntary vaccination had not reduced smallpox mortality,<ref name = "Brunton_2008" />{{rp|43}} but the Vaccination Act 1853 was so badly implemented that it had little impact on the number of children vaccinated in [[England]] and [[Wales]].<ref name = "Brunton_2008" />{{rp|50}}\n\n[[File:Poster for vaccination against smallpox.jpg|thumb|right|A 1979 poster from [[Lagos]], [[Nigeria]], to promote the worldwide eradication of smallpox.<ref name = "Magner_2009">{{Cite book|title=A History of Infectious Diseases and the Microbial World | vauthors = Magner LN |publisher=ABC-CLIO|year=2009|isbn=9780275995058 }}</ref>{{rp|116}}]]\nIn the United States of America compulsory vaccination laws were upheld in the 1905 landmark case [[Jacobson v. Massachusetts]] by the [[Supreme Court of the United States]]. The Supreme Court ruled that laws could require vaccination to protect the public from dangerous communicable diseases. However, in practice the United States had the lowest rate of vaccination among industrialized nations in the early 20th century. Compulsory vaccination laws began to be enforced in the United States after [[World War II]]. In 1959 the [[World Health Organization]] (WHO) called for the [[Smallpox|eradication of smallpox]] worldwide, as smallpox was still endemic in 33 countries. In the 1960s six to eight children died each year in the United States from vaccination-related complications. According to the WHO there were in 1966 about 100 million cases of smallpox worldwide, causing an estimated two million deaths. In the 1970s there was such a small risk of contracting smallpox that the [[United States Public Health Service]] recommended for routine smallpox vaccination to be ended. By 1974 the WHO smallpox vaccination program had confined smallpox to parts of [[Pakistan]], India, [[Bangladesh]], [[Ethiopia]] and [[Somalia]]. In 1977 the WHO recorded the last case of smallpox infection acquired outside a laboratory in Somalia. In 1980 the WHO officially declared the world free of smallpox.<ref name = "Magner_2009" />{{rp|115\u2013116}}\n\nIn 1974 the WHO adopted the goal of universal vaccination by 1990 to protect children against six preventable [[infectious diseases]]: [[measles]], [[poliomyelitis]], [[diphtheria]], [[whooping cough]], [[tetanus]], and [[tuberculosis]].<ref name = "Magner_2009" />{{rp|119}} In the 1980s only 20 to 40% of children in developing countries were vaccinated against these six diseases. In wealthy nations the number of measles cases had dropped dramatically after the introduction of the [[measles vaccine]] in 1963. WHO figures demonstrate that in many countries a decline in measles vaccination leads to a resurgence in measles cases. Measles are so contagious that public health experts believe a vaccination rate of 100% is needed to control the disease.<ref name = "Magner_2009" />{{rp|120}} Despite decades of mass vaccination polio remains a threat in India, [[Nigeria]], [[Somalia]], [[Niger]], [[Afghanistan]], [[Bangladesh]] and [[Indonesia]]. By 2006 global health experts concluded that the eradication of polio was only possible if the supply of [[drinking water]] and [[sanitation]] facilities were improved in [[slums]].<ref name = "Magner_2009" />{{rp|124}} The deployment of a combined [[DPT vaccine]] against [[diphtheria]], [[pertussis]] (whooping cough), and [[tetanus]] in the 1950s was considered a major advancement for public health. But in the course of vaccination campaigns that spanned decades, DPT vaccines became associated with high incidences of side effects. Despite improved DPT vaccines coming onto the market in the 1990s DPT vaccines became the focus of [[anti-vaccination]] campaigns in wealthy nations. As immunization rates fell outbreaks of [[pertussis]] increased in many countries.<ref name = "Magner_2009" />{{rp|128}}\n\nIn 2000, the [[Global Alliance for Vaccines and Immunization]] was established to strengthen routine vaccinations and introduce new and under-used vaccines in countries with a per capita GDP of under US$1000.<ref>{{cite journal |vauthors=Jaupart P, Dipple L, Dercon S |date=3 December 2019 |title=Has Gavi lived up to its promise? Quasi-experimental evidence on country immunisation rates and child mortality |journal=BMJ Global Health |volume=3 |issue=4 |page=e001789 |doi=10.1136/bmjgh-2019-001789 |pmc=6936423 |pmid=31908857}}</ref>"}},
{"article_title": "Vim (text editor)", "pageid": "32478", "revid": "1057089465", "timestamp": "2021-11-25T11:23:51Z", "history_paths": [["Vim (text editor) --- Introduction ---", "History"]], "categories": ["1991 software", "amiga software", "beos text editors", "classic mac os text editors", "computer science in the netherlands", "cross-platform free software", "dos text editors", "free file comparison tools", "free software programmed in c", "free text editors", "information technology in the netherlands", "linux text editors", "macos text editors", "morphos software", "openvms text editors", "os/2 text editors", "termcap", "unix text editors", "vi", "windows text editors", "text editors that use gtk", "free html editors", "linux integrated development environments", "hex editors", "free integrated development environments", "free integrated development environments for python", "free and open-source software", "command-line software", "console applications"], "heading_tree": {"Vim (text editor) --- Introduction ---": {"History": {}, "Interface": {"Modes": {}}, "Customization": {}, "Features and improvements over vi": {}, "Vim script": {"Examples": {}}, "Availability": {}, "Neovim": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Vim (text editor) --- Introduction ---|History": "Vim's forerunner, [[Stevie (text editor)|Stevie (ST Editor for VI Enthusiasts)]], was created by Tim Thompson for the [[Atari ST]] in 1987<ref name=stevie>{{cite web |first=Tim |last=Thompson |date=2000-03-26 |url=http://nosuch.com/tjt/stevie/ |title=Stevie |access-date=2010-12-27}}</ref><ref name="stevie-usenet">{{cite newsgroup |title=A mini-vi for the ST |author=Tim Thompson |date=1987-06-28 |newsgroup=comp.sys.atari.st |message-id=129@glimmer.UUCP |url=http://groups.google.com/group/comp.sys.atari.st/msg/8db96f888d778a32?dmode=source |access-date=2010-12-27}}</ref> and further developed by Tony Andrews<ref name=stevie/><ref name="v15i026">{{cite newsgroup |title=v15i037: Stevie, an "aspiring" VI clone for Unix, OS/2, Amiga |author=Tony Andrews |date=1988-06-06 |newsgroup=comp.sources.unix |message-id=893@fig.bbn.com |url=http://groups.google.com/group/comp.sources.unix/msg/1fccf6a82259beed?dmode=source |access-date=2010-12-27}}</ref> and G.R. (Fred) Walter.<ref>{{cite web|author1=Vim|title=intro.txt|url=https://vimhelp.appspot.com/intro.txt.html|website=Vim Help|publisher=Vim|access-date=9 July 2016|archive-url=https://web.archive.org/web/20160709041643/https://vimhelp.appspot.com/intro.txt.html |language=en|date=20 January 2015|archive-date=9 July 2016}}</ref><ref>{{cite web|title=vim(1)|url=http://linux.die.net/man/1/vim|website=die.net|publisher=Vim|access-date=9 July 2016|archive-url=https://web.archive.org/web/20160709133642/http://linux.die.net/man/1/vim |archive-date=9 July 2016|date=11 April 2006|quote=Vim is based on Stevie, worked on by: Tim Thompson, Tony Andrews and G.R. (Fred) Walter. Although hardly any of the original code remains.}}</ref>\n\nBasing his work on Stevie, [[Bram Moolenaar]] began working on Vim for the [[Amiga]] computer in 1988, with the first public release (Vim v1.14) in 1991.<ref>{{cite web|url=http://moolenaar.net/vimstory.pdf|title=The continuing story of Vim}}</ref><ref>{{cite web|url=https://jovicailic.org/2014/06/the-history-of-vim/|title=The history of Vim \u2013 Jovica Ilic|date=5 June 2014|access-date=25 January 2020}}</ref>{{better source needed|date=January 2020}}\n\nAt the time of its first release, the name "Vim" was an acronym for "Vi IMitation", but this changed to "'Vi IMproved" late in 1993.<ref name="vile-FAQ">{{cite web |url=https://invisible-island.net/vile/vile.faq.html#clone_began |title=VILE (Vi Like Emacs) \u2013 Frequently Asked Questions (FAQ) |access-date=7 September 2019}}</ref>\n\n{{collapse top|Release history}}\n{| class="wikitable"\n|-\n! style="text-align:left;" | Date\n! style="text-align:left;" | Version\n! style="text-align:left;" | Changes and additions\n|-\n| June, 1987\n| N/A\n| Tim Thompson releases Stevie (ST editor for VI enthusiasts), a limited vi clone for the [[Atari ST]], posting the source on [[Usenet]].<ref name=stevie /><ref name="stevie-usenet" />\n|-\n| June, 1988\n| N/A\n| Tony Andrews improves Stevie, and ports it to Unix and [[OS/2]], releasing version 3.10 on [[Usenet]].<ref name=stevie/><ref name="v15i026"/>\n\n|-\n| 1988\n| 1.0\n| Bram Moolenaar creates '''Vi IMitation''' for the Amiga, based on Stevie, never publicly released\n|-\n| November 2, 1991\n| 1.14<ref name="history">{{cite web |first=Bram |last=Moolenaar |date=2002-01-15 |url=http://www.free-soft.org/FSM/english/issue01/vim.html |title=Vim, an open-source text editor |access-date=2005-10-24}}</ref>|| First public release for the [[Amiga]] on [[Fred Fish]] disk #591<ref>{{cite web|url=http://cd.textfiles.com/fredfish/v1.6/FF_Disks/571-600/FF_591/Contents|title=Textfiles.com}}</ref>\n|-\n| 1992\n| 1.22<ref name="history"/>\n| Port to Unix, never publicly released.<ref name="vile-FAQ"/> Vim now competes with ''[[vi]]''.\n|-\n| December 14, 1993\n| 2.0<ref name="filewatcher">{{cite web |title=Filewatcher |url=http://www.filewatcher.com/b/ftp/ftp.twaren.net/pub/Unix/Editors/Vim/old.0.0.html |access-date=February 26, 2011 |archive-url=https://web.archive.org/web/20110711001335/http://www.filewatcher.com/b/ftp/ftp.twaren.net/pub/Unix/Editors/Vim/old.0.0.html |archive-date=July 11, 2011 |url-status=dead |df=mdy-all }}</ref>\n| This is the first release using the name '''Vi IMproved'''.<ref name="vile-FAQ"/>\n|-\n| August 12, 1994\n| 3.0<ref name="history"/>\n| Support for multiple windows\n|-\n| May 29, 1996\n| 4.0<ref name="history"/><ref>{{cite web |date=2004-03-12 |url=http://www.vim.org/htmldoc/version4.html |title=Official Vim Manual, Version 4 summary |access-date=2008-08-06}}</ref>\n| [[Graphical user interface]]\n|-\n| February 19, 1998\n| 5.0<ref name="history"/><ref>{{cite web |date=2004-01-17 |url=http://www.vim.org/htmldoc/version5.html |title=Official Vim Manual, Version 5 summary |access-date=2008-08-06}}</ref>|| [[Syntax highlighting]], basic [[Scripting language|scripting]] (user defined functions, commands, etc.)\n|-\n| April 6, 1998\n| 5.1\n| [[Software bug|Bug]] fixes, various improvements\n|-\n| April 27, 1998\n| 5.2\n| Long line support, file browser, dialogs, popup menu, select mode, session files, user defined functions and commands, [[Tcl]] interface, etc.\n|-\n| August 31, 1998\n| 5.3\n| Bug fixes, etc.\n|-\n| July 25, 1999\n| 5.4\n| Basic file encryption, various improvements\n|-\n| September 19, 1999\n| 5.5\n| Bug fixes, various improvements\n|-\n| January 16, 2000\n| 5.6\n| New syntax files, bug fixes, etc.\n|-\n| June 24, 2000\n| 5.7\n| New syntax files, bug fixes, etc.\n|-\n| May 31, 2001\n| 5.8\n| New syntax files, bug fixes, etc.\n|-\n| September 26, 2001\n| 6.0<ref name="history"/><ref>{{cite web |date=2004-03-12 |url=http://www.vim.org/htmldoc/version6.html |title=Official Vim Manual, Version 6 summary |access-date=2008-08-06}}</ref>|| [[Folding editor|Folding]], [[Plug-in (computing)|plugins]], multi-language, etc.\n|-\n| March 24, 2002\n| 6.1\n| Bug fixes\n|-\n| June 1, 2003\n| 6.2\n| GTK2 and libgnome2 support, Arabic language support, :try command, minor features, bug fixes\n|-\n| June 7, 2004\n| 6.3\n| Bug fixes, translation updates, mark improvements\n|-\n| October 15, 2005\n| 6.4\n| Bug fixes, updates to Perl, Python, and Ruby support\n|-\n| May 7, 2006\n| 7.0<ref>{{cite web |date=2016-07-17 |url=https://vimhelp.org/version7.txt.html |title=Vim Reference Manual, Version 7 |access-date=2019-01-13}}</ref>|| [[Spell checker|Spell checking]], [[Autocomplete|code completion]], tab pages (multiple viewports/window layouts), current line and column highlighting, undo branches, and more\n|-\n| May 12, 2007\n| 7.1\n| Bug fixes, new syntax and runtime files, etc.\n|-\n| August 9, 2008\n| 7.2<ref>{{cite web|url=http://groups.google.com/group/vim_announce/browse_thread/thread/2c89671dd928812f|title=Google Groups|website=groups.google.com}}</ref>|| Floating point support in scripts, refactored screen drawing code, bug fixes, new syntax files, etc.\n|-\n| August 15, 2010\n| 7.3\n| [[Lua (programming language)|Lua]] support, Python3 support, [[Blowfish (cipher)|Blowfish]] encryption, persistent undo/redo\n|-\n| August 10, 2013\n| 7.4<ref>[https://groups.google.com/forum/#!topic/vim_announce/knOQ_t_H5to Google Discussiegroepen]. Groups.google.com. Retrieved on 2013-12-09.</ref>\n| A new, faster regular expression engine.\n|-\n| September 12, 2016\n| 8.0<ref>{{cite web |url=https://groups.google.com/forum/#!topic/vim_announce/EKTuhjF3ET0 |title=Vim 8.0 released! |access-date=September 12, 2016 |author=Bram Moolenaar}}</ref>\n| Asynchronous I/O support, jobs, lambdas, etc.\n|-\n| May 18, 2018\n| 8.1<ref>{{cite web\n|url=https://www.vim.org/vim-8.1-released.php |title=Vim 8.1 is released! |access-date=May 18, 2018 |author=Bram Moolenaar}}</ref>\n| Terminal window support and terminal gdb plugin.\n|-\n| December 13, 2019\n| 8.2<ref>{{cite web\n|url=https://www.vim.org/vim-8.2-released.php |title=Vim 8.2 is released! |access-date=December 13, 2019 |author=Bram Moolenaar}}</ref>\n| Popup windows, text properties.\n|}\n{{collapse bottom}}"}},
{"article_title": "Vacuum tube", "pageid": "32496", "revid": "1062627597", "timestamp": "2021-12-29T15:57:29Z", "history_paths": [["Vacuum tube --- Introduction ---", "History and development"]], "categories": ["vacuum tubes", "1904 in science", "1904 in technology", "electrical components", "english inventions", "glass applications", "telecommunications-related introductions in 1904", "vacuum"], "heading_tree": {"Vacuum tube --- Introduction ---": {"Classifications": {}, "Description": {}, "History and development": {"Diodes": {}, "Triodes": {}, "Tetrodes and pentodes": {}, "Multifunction and multisection tubes": {}, "Beam power tubes": {}, "Gas-filled tubes": {}, "Miniature tubes": {"Sub-miniature tubes": {}}, "Improvements in construction and performance": {}, "Indirectly heated cathodes": {}, "Use in electronic computers": {"Colossus": {}, "Whirlwind and \"special-quality\" tubes": {}}}, "Heat generation and cooling": {}, "Tube packages": {}, "Names": {}, "Special-purpose tubes": {}, "Powering the tube": {"Batteries": {}, "AC power": {}}, "Reliability": {"Vacuum": {}, "Transmitting tubes": {}, "Receiving tubes": {}, "Failure modes": {"Catastrophic failures": {}, "Degenerative failures": {}, "Other failures": {}}}, "Testing": {}, "Other vacuum tube devices": {"Cathode ray tubes": {}, "Electron multipliers": {}}, "Vacuum tubes in the 21st century": {"Niche applications": {"Audiophiles": {}}, "Displays": {"Cathode ray tube": {}, "Vacuum fluorescent display": {}}, "Vacuum tubes using field electron emitters": {}}, "Characteristics": {"Space charge of a vacuum tube": {}, "Voltage - Current characteristics of vacuum tube": {}, "Size of electrostatic field": {}}, "Patents": {}, "See also": {}, "Explanatory notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Vacuum tube --- Introduction ---|History and development": "[[File:Edison effect bulb 1.jpg|thumb|upright=0.5|One of Edison's experimental bulbs]]\nThe 19th century saw increasing research with evacuated tubes, such as the [[Geissler tube|Geissler]] and [[Crookes tube]]s. The many scientists and inventors who experimented with such tubes include [[Thomas Edison]], [[Eugen Goldstein]], [[Nikola Tesla]], and [[Johann Wilhelm Hittorf]]. With the exception of early [[light bulb]]s, such tubes were only used in scientific research or as novelties. The groundwork laid by these scientists and inventors, however, was critical to the development of subsequent vacuum tube technology.\n\nAlthough [[thermionic emission]] was originally reported in 1873 by [[Frederick Guthrie]],<ref>{{cite book |first=Frederick |last=Guthrie |author-link=Frederick Guthrie |title=Magnetism and Electricity |date=1876 |location=London and Glasgow |publisher=William Collins, Sons, & Company |url=https://archive.org/details/magnetismandele00guthgoog |page=[https://archive.org/details/magnetismandele00guthgoog/page/n5 1] }}{{page needed|date=January 2015}}</ref> it was Thomas Edison's apparently independent discovery of the phenomenon in 1883 that became well known. Although Edison was aware of the unidirectional property of current flow between the filament and the anode, his interest (and patent<ref>Thomas A. Edison {{US patent|307031}} "Electrical Indicator", Issue date: 1884</ref>) concentrated on the sensitivity of the anode current to the current through the filament (and thus filament temperature). It was years later that [[John Ambrose Fleming]] applied the rectifying property of the Edison effect to [[Detector_(radio)|detection]] of radio signals, as an improvement over the magnetic detector.<ref name=FlemingSci01>Fleming, J. A. (1934). [https://archive.org/details/in.ernet.dli.2015.80583/page/n151/mode/2up?view=theater ''Memories of a Scientific Life'']. London, UK: Marshall, Morgan & Scott, Ltd.  pp. 136 - 143. Retrieved Nov. 2021.</ref>\n\nAmplification by vacuum tube became practical only with [[Lee de Forest]]'s 1907 invention of the three-terminal "[[audion]]" tube, a crude form of what was to become the [[triode]].<ref>{{Cite journal|last=Guarnieri|first=M.|date=2012|title=The age of vacuum tubes: Early devices and the rise of radio communications|journal=IEEE Ind. Electron. M.|volume=6|issue=1|pages=41\u201343|doi=10.1109/MIE.2012.2182822|s2cid=23351454}}</ref> Being essentially the first electronic amplifier,<ref>{{Citation |first=Thomas |last=White |title=United States Early Radio History |url=https://earlyradiohistory.us/sec010.htm |url-status=live |archive-url=https://web.archive.org/web/20120818042321/http://earlyradiohistory.us/sec010.htm |archive-date=18 August 2012 }}</ref> such tubes were instrumental in long-distance telephony (such as the first coast-to-coast telephone line in the US) and [[public address system]]s, and introduced a far superior and versatile technology for use in radio transmitters and receivers. The electronics revolution of the 20th century arguably began with the invention of the triode vacuum tube.\n\n {{Main|Diode}}\n[[File:Fleming valves.jpg|thumb|Fleming's first diodes]]\n\nAt the end of the 19th century, radio or wireless technology was in an early stage of development and the [[Marconi Company]] was engaged in development and construction of radio communication systems. Marconi appointed English physicist [[John Ambrose Fleming]] as scientific advisor in 1899. Fleming had been engaged as scientific advisor to Edison Telephone (1879), as scientific advisor at Edison Electric Light (1882), and was also technical consultant to [[Edison and Swan Electric Light Company|Edison-Swan]].<ref>{{cite web|title=Mazda Valves|url=http://www.vintage-technology.info/pages/ephemera/vemazda.htm|archive-url=https://web.archive.org/web/20130628205923/http://www.vintage-technology.info/pages/ephemera/vemazda.htm|archive-date=2013-06-28|access-date=2017-01-12}}</ref> One of Marconi's needs was for improvement of the [[Detector_(radio)|detector]]. Marconi had developed a [[Magnetic_detector|magnetic detector]], which was less responsive to natural sources of radio frequency interference than the [[coherer]], but the magnetic detector only provided an audio frequency signal to a telephone receiver. A reliable detector that could drive a printing instrument was needed. As a result of experiments conducted on Edison effect bulbs,<ref name=FlemingSci01/> Fleming developed a vacuum tube that he termed the ''oscillation valve'' because it passed current in only one direction.<ref>Fleming (1934) [https://archive.org/details/in.ernet.dli.2015.80583/page/n155/mode/2up?view=theater pp. 138 - 143].</ref> The cathode was a carbon lamp filament, heated by passing current through it, that produced thermionic emission of electrons. Electrons that had been emitted from the cathode were attracted to the ''[[Plate electrode|plate]]'' (''[[anode]]'') when the plate was at a positive voltage with respect to the cathode. Electrons could not pass in the reverse direction because the plate was not heated and not capable of thermionic emission of electrons. Fleming filed a patent for these tubes, assigned to the Marconi company, in the UK in November 1904 and this patent was issued in September 1905.<ref>Editors (Sept 1954) [https://worldradiohistory.com/UK/Wireless-World/50s/Wireiless-World-1954-09.pdf "World of Wireless"] ''Wireless World'' p. 411. Retrieved Nov. 2021.</ref> Later known as the Fleming valve, the oscillation valve was developed for the purpose of rectifying radio frequency current as the detector component of radio receiver circuits.<ref name=FlemingSci01/><ref>Fleming, J. A. (1905). [https://patentimages.storage.googleapis.com/23/09/50/6d4980acdfed12/US803684.pdf ''Instrument for Converting Alternating Electric Currents into Continuous Currents'']. U. S. patent 803,684. Retrieved Nov 2021.</ref>\n\nWhile offering no advantage over the electrical sensitivity of [[crystal detector]]s,<ref name="navywireless1911">Robison, S. S. (1911). [https://archive.org/details/manualofwireless00robirich/page/131/mode/2up?view=theater'' Manual of Wireless Telegraphy for the use of Naval Electricians'']. Annapolis, MD: United States Naval Institute. p. 124 fig. 84; pp. 131, 132. Retrieved Nov 2021</ref> the Fleming valve offered advantage, particularly in shipboard use, over the difficulty of adjustment of the crystal detector and the susceptibility of the crystal detector to being dislodged from adjustment by vibration or bumping.<ref>Keen, R. (1922). [https://archive.org/details/DirectionAndPositionFindingByWireless/page/n98/mode/2up?view=theater  ''Direction and Position Finding by Wireless'']. London: The Wireless Press, Ltd. p. 74. Retrieved Nov. 2021.</ref>\n\nThe first vacuum tube diodes designed for rectifier application in power supply circuits were introduced in April 1915 by [[Saul Dushman]] of General Electric.<ref>Dushman, S. (1915). [https://archive.org/details/generalelectricr18gene/page/156/mode/2up?view=theater "A New Device for Rectifying High Tension Alternating Currents - The Kenotron"] ''General Electric Review'' pp. 156 - 167. Retrieved Nov. 2021</ref><ref>Dushman, S. (1915). [https://patentimages.storage.googleapis.com/8a/93/b3/2b97df34eaf78e/US1287265.pdf ''Electrical Discharge Device'']. U. S. patent 1,287,265. Retrieved Nov. 2021.</ref>\n\n {{Main|Triode}}\n[[File:Triode tube 1906.jpg|thumb|The first triode, the de Forest [[Audion]], invented in 1906]]\n[[File:Triody var.jpg|right|thumb|Triodes as they evolved over 40 years of tube manufacture, from the RE16 in 1918 to a 1960s era miniature tube]]\n[[File:Triode.PNG|thumb|upright|Triode symbol. From top to bottom: plate (anode), control grid, cathode, heater (filament)]]\n\nOriginally, the only use for tubes in radio circuits was for [[Rectifier|rectification]], not amplification. In 1906, [[Robert von Lieben]] filed for a patent<ref>{{cite web | title = Robert von Lieben \u2014 Patent Nr 179807 Dated November 19, 1906 | publisher = Kaiserliches Patentamt | date = 19 November 1906 | url = http://www.hts-homepage.de/Lieben/DRP179807.pdf | access-date = 30 March 2008 | url-status = live | archive-url = https://web.archive.org/web/20080528125703/http://www.hts-homepage.de/Lieben/DRP179807.pdf | archive-date = 28 May 2008 }}</ref> for a [[cathode ray tube]] which included magnetic deflection. This could be used for amplifying audio signals and was intended for use in telephony equipment. He would later help refine the [[triode]] vacuum tube.\n\nHowever, [[Lee de Forest]] is credited with inventing the triode tube in 1907 while experimenting to improve his original (diode) [[Audion]].<ref>Fleming, J. A. (1919). [https://archive.org/details/thermionicvalvei00flemrich/page/114/mode/2up?view=theater'' The Thermionic Valve and its Developments in Radiotelegraphy and Telephony'']. London, UK: The Wireless Press Ltd. p. 115. Retrieved Oct 2021</ref> By placing an additional electrode between the filament ([[cathode]]) and [[plate electrode|plate]] (anode), he discovered the ability of the resulting device to amplify signals. As the voltage applied to the [[control grid]] (or simply "grid") was lowered from the cathode's voltage to somewhat more negative voltages, the amount of current from the filament to the plate would be reduced. The negative electrostatic field created by the grid in the vicinity of the cathode would inhibit the passage of emitted electrons and reduce the current to the plate. With the voltage of the grid less than that of the cathode, no direct current could pass from the cathode to the grid. \n\nThus a change of voltage applied to the grid, requiring very little power input to the grid, could make a change in the plate current and could lead to a much larger voltage change at the plate; the result was voltage and power [[amplifier|amplification]]. In 1908, de Forest was granted a patent ({{US patent|879532}}) for such a three-electrode version of his original Audion for use as an electronic amplifier in radio communications. This eventually became known as the triode.\n\n[[File:General electric pliotron pp schenectady 3.jpg|thumb|upright|General Electric Company Pliotron, [[Science History Institute]] ]]\nde Forest's original device was made with conventional vacuum technology. The vacuum was not a "hard vacuum" but rather left a very small amount of residual gas. The physics behind the device's operation was also not settled. The residual gas would cause a blue glow (visible ionization) when the plate voltage was high (above about 60 volts). In 1912, de Forest brought the Audion to Harold Arnold in AT&T's engineering department. Arnold recommended that AT&T purchase the patent, and AT&T followed his recommendation. Arnold developed high-vacuum tubes which were tested in the summer of 1913 on AT&T's long-distance network.<ref>{{cite web |url=http://www.corp.att.com/attlabs/reputation/timeline/15tel.html |title=AT&T Labs Research | AT&T |access-date=2013-08-21 |url-status=live |archive-url=https://web.archive.org/web/20131005081147/http://www.corp.att.com/attlabs/reputation/timeline/15tel.html |archive-date=5 October 2013 }}</ref> The high-vacuum tubes could operate at high plate voltages without a blue glow.\n\nFinnish inventor [[Eric Tigerstedt]] significantly improved on the original triode design in 1914, while working on his [[sound-on-film]] process in Berlin, Germany. Tigerstedt's innovation was to make the electrodes concentric cylinders with the cathode at the centre, thus greatly increasing the collection of emitted electrons at the anode.<ref>{{cite book |first1=Antti V. |last1=R\u00e4is\u00e4nen |first2=Arto |last2=Lehto |title=Radio Engineering for Wireless Communication and Sensor Applications |url=https://archive.org/details/radioengineering00rais_350 |url-access=limited |page=[https://archive.org/details/radioengineering00rais_350/page/n25 7] |publisher=Artech House |date=2003 |isbn=978-1580536691}}</ref>\n\n[[Irving Langmuir]] at the [[General Electric]] research laboratory ([[Schenectady, New York]]) had improved [[Wolfgang Gaede]]'s [[diffusion pump|high-vacuum diffusion pump]] and used it to settle the question of thermionic emission and conduction in a vacuum. Consequently, General Electric started producing hard vacuum triodes (which were branded Pliotrons) in 1915.<ref>{{Cite web|url=http://edisontechcenter.org/GEresearchLab.html |title=General Electric Research Lab History |date=2015 |author=Edison Tech Center |website=edisontechcenter.org |access-date=2018-11-12}}</ref> Langmuir patented the hard vacuum triode, but de Forest and AT&T successfully asserted priority and invalidated the patent.\n\nPliotrons were closely followed by the French type '[[TM (triode)|TM]]' and later the English type 'R' which were in widespread use by the allied military by 1916. Historically, vacuum levels in production vacuum tubes typically ranged from 10 [[Pascal (pressure)|\u00b5Pa]] down to 10 nPa  ({{convert|10|uPa|Torr|sigfig=1|lk=out|disp=out}} down to {{convert|10|nPa|Torr|sigfig=1|disp=out}}).<ref>J.Jenkins and W.H.Jarvis, "Basic Principles of Electronics, Volume 1 Thermionics", Pergamon Press (1966), Ch.1.10 p.9</ref>\n\nThe triode and its derivatives (tetrodes and pentodes) are [[transconductance]] devices, in which the controlling signal applied to the grid is a ''voltage'', and the resulting amplified signal appearing at the anode is a ''current''.<ref>Departments of the Army and the Air Force (1952). [https://archive.org/details/BasicTheoryAndApplicationOfElectronTubes/page/n53/mode/2up?view=theater ''Basic Theory and Application of Electron Tubes'']. Washington D. C.: USGPO. p. 42. Retrieved Oct 2021</ref> Compare this to the behavior of the [[bipolar junction transistor]], in which the controlling signal is a current and the output is also a current.\n\nFor vacuum tubes, transconductance or mutual conductance ({{math|''g''<sub>m</sub>}}) is defined as the change in the plate(anode)/cathode current divided by the corresponding change in the grid to cathode voltage, with a constant plate(anode) to cathode voltage. Typical values of {{math|''g''<sub>m</sub>}} for a small-signal vacuum tube are 1 to 10 millisiemens. It is one of the three 'constants' of a vacuum tube, the other two being its gain \u03bc and plate resistance {{math|''R''<sub>p</sub>}} or {{math|''R''<sub>a</sub>}}. The Van der Bijl equation defines their relationship as follows: <math>g_m = {\\mu \\over R_p}</math>\n\nThe non-linear operating characteristic of the triode caused early tube audio amplifiers to exhibit harmonic distortion at low volumes. Plotting plate current as a function of applied grid voltage, it was seen that there was a range of grid voltages for which the transfer characteristics were approximately linear.\n\nTo use this range, a negative bias voltage had to be applied to the grid to position the [[direct current|DC]] operating point in the linear region. This was called the idle condition, and the plate current at this point the "idle current". The controlling voltage was superimposed onto the bias voltage, resulting in a linear variation of plate current in response to positive and negative variation of the input voltage around that point.\n\nThis concept is called ''[[grid bias]]''. Many early radio sets had a third battery called the "C battery" (unrelated to the present-day [[C battery|C cell]], for which the letter denotes its size and shape). The C battery's positive terminal was connected to the cathode of the tubes (or "ground" in most circuits) and whose negative terminal supplied this bias voltage to the grids of the tubes.\n\nLater circuits, after tubes were made with heaters isolated from their cathodes, used [[cathode bias]]ing, avoiding the need for a separate negative power supply. For cathode biasing, a relatively low-value resistor is connected between the cathode and ground. This makes the cathode positive with respect to the grid, which is at ground potential for DC.\n\nHowever C batteries continued to be included in some equipment even when the "A" and "B" batteries had been replaced by power from the AC mains. That was possible because there was essentially no current draw on these batteries; they could thus last for many years (often longer than all the tubes) without requiring replacement.\n\nWhen triodes were first used in radio transmitters and receivers, it was found that tuned amplification stages had a tendency to oscillate unless their gain was very limited. This was due to the parasitic capacitance between the plate (the amplifier's output) and the control grid (the amplifier's input), known as the [[Miller effect|Miller capacitance]].\n\nEventually the technique of ''neutralization'' was developed whereby the RF transformer connected to the plate (anode) would include an additional winding in the opposite phase. This winding would be connected back to the grid through a small capacitor, and when properly adjusted would cancel the Miller capacitance. This technique was employed and led to the success of the [[Neutrodyne]] radio during the 1920s.\nHowever, neutralization required careful adjustment and proved unsatisfactory when used over a wide range of frequencies.\n\n {{Main|Tetrode|Pentode}}\n[[File:Tetrode.PNG|thumb|right|150px|Tetrode symbol. From top to bottom: plate (anode), screen grid, control grid, cathode, heater (filament).]]\n\nTo combat the stability problems of the triode as a radio frequency amplifier due to grid-to-plate capacitance, the physicist [[Walter H. Schottky]] invented the tetrode or ''screen grid tube'' in 1919.<ref>{{Cite journal|last=Guarnieri|first=M.|date=2012|title=The age of vacuum tubes: the conquest of analog communications|journal=IEEE Ind. Electron. M.|volume=6|issue=2|pages=52\u201354|doi=10.1109/MIE.2012.2193274|s2cid=42357863}}</ref> He showed that the addition of an electrostatic shield between the control grid and the plate could solve the problem. This design was refined by Hull and Williams.<ref>Beatty, R. T. (Oct. 1927) [https://worldradiohistory.com/UK/Experimental-Wireless/20s/Experimental%20Wireless-1927-10.pdf "The Shielded Plate Valve as a High-Frequency Amplifier"]. ''Wireless Engineer'' p. 621</ref>   The added grid became known as the ''[[screen grid]]'' or ''shield grid''. The screen grid is operated at a positive voltage significantly less than the plate voltage and it is [[bypass capacitor|bypassed]] to ground with a capacitor of low impedance at the frequencies to be amplified.<ref name="Landee">Landee, Davis, Albrecht (1957) [https://archive.org/stream/Electronic_Designers_Handbook_Robert_Landee_Donovan_Davis_Albert_Albrecht_1957#page/n61 ''Electronic Designers' Handbook'']. New York: McGraw-Hill. pp. 3-34 - 3-38.</ref>\nThis arrangement substantially decouples the plate and the [[control grid]], eliminating the need for neutralizing circuitry at medium wave broadcast frequencies. The screen grid also largely reduces the influence of the plate voltage on the space charge near the cathode, permitting the tetrode to produce greater voltage gain than the triode in amplifier circuits. While the amplification factors of typical triodes commonly range from below ten to around 100, tetrode amplification factors of 500 are common. Consequently, higher voltage gains from a single tube amplification stage became possible, reducing the number of tubes required. Screen grid tubes were put on the market in late 1927.<ref name="Thrower">K. R. Thrower, (2009) ''British Radio Valves The Classic Years: 1926-1946'', Reading, UK: Speedwell, p. 3</ref>\n\n[[File:TM11-662 figure 72 tetrode anode characteristic.jpg|thumb|right|150px|The useful region of operation of the screen grid tube (tetrode) as an amplifier is limited to anode potentials in the straight portions of the characteristic curves greater than the screen grid potential.]]\nHowever, the useful region of operation of the screen grid tube as an amplifier was limited to plate voltages greater than the screen grid voltage, due to [[secondary emission]] from the plate. In any tube, electrons strike the plate with sufficient energy to cause the emission of electrons from its surface. In a triode this secondary emission of electrons is not important since they are simply re-captured by the plate. But in a tetrode they can be captured by the screen grid since it is also at a positive voltage, robbing them from the plate current and reducing the amplification of the tube. Since secondary electrons can outnumber the primary electrons over a certain range of plate voltages, the plate current can decrease with increasing plate voltage. This is the ''dynatron region'' <ref>Happell, Hesselberth (1953). [https://archive.org/details/Engineering_Electronics_George_Happell_Wilfred_Hesselberth_1953/page/n97/mode/2up ''Engineering Electronics'']. New York: McGraw-Hill. p. 88</ref> or ''tetrode kink'' and is an example of [[negative resistance]] which can itself cause instability.<ref>[http://www.cjseymour.plus.com/elec/valves/valves.htm Introduction to Thermionic Valves (Vacuum Tubes)] {{webarchive|url=https://web.archive.org/web/20070528141924/http://www.cjseymour.plus.com/elec/valves/valves.htm |date=28 May 2007 }}, Colin J. Seymour</ref> Another undesirable consequence of secondary emission is that screen current is increased, which may cause the screen to exceed its power rating.\n\nThe otherwise undesirable negative resistance region of the plate characteristic was exploited with the [[dynatron oscillator]] circuit to produce a simple oscillator only requiring connection of the plate to a resonant [[LC circuit]] to oscillate. The dynatron oscillator operated on the same principle of negative resistance as the [[tunnel diode]] oscillator many years later.\n\nThe dynatron region of the screen grid tube was eliminated by adding a grid between the screen grid and the plate to create the [[pentode]].  The [[suppressor grid]] of the pentode was usually connected to the cathode and its negative voltage relative to the anode repelled secondary electrons so that they would be collected by the anode instead of the screen grid. The term ''pentode'' means the tube has five electrodes. The pentode was invented in 1926 by [[Bernard D. H. Tellegen]]<ref>{{Cite web |url=http://www.philips-historische-producten.nl/tube-uk.html |title=Philips Historical Products: Philips Vacuum Tubes |access-date=3 November 2013 |url-status=live |archive-url=https://web.archive.org/web/20131106031350/http://www.philips-historische-producten.nl/tube-uk.html |archive-date=6 November 2013 }}</ref> and became generally favored over the simple tetrode. Pentodes are made in two classes: those with the suppressor grid wired internally to the cathode (e.g. EL84/6BQ5) and those with the suppressor grid wired to a separate pin for user access (e.g. 803, 837). An alternative solution for power applications is the [[beam tetrode]] or ''beam power tube'', discussed below.\n\n [[File:Heptode.svg|thumb|right|160px|The pentagrid converter contains five grids between the cathode and the plate (anode)]]\n\n[[Superheterodyne receiver]]s require a [[local oscillator]] and [[Frequency mixer|mixer]], combined in the function of a single [[pentagrid converter]] tube. Various alternatives such as using a combination of a [[triode]] with a [[Pentagrid converter#Hexode|hexode]] and even an [[Pentagrid converter#Octode|octode]] have been used for this purpose. The additional grids include [[control grid]]s (at a low potential) and [[Tetrode|screen grids]] (at a high voltage). Many designs use such a screen grid as an additional anode to provide feedback for the oscillator function, whose current adds to that of the incoming radio frequency signal. The pentagrid converter thus became widely used in AM receivers, including the miniature tube version of the "[[All American Five]]". Octodes, such as the 7A8, were rarely used in the United States, but much more common in Europe, particularly in battery operated radios where the lower power consumption was an advantage.\n\nTo further reduce the cost and complexity of radio equipment, two separate structures (triode and pentode for instance) can be combined in the bulb of a single ''multisection tube''. An early example is the [[Loewe 3NF]]. This 1920s device has three triodes in a single glass envelope together with all the fixed capacitors and resistors required to make a complete radio receiver. As the Loewe set had only one tube socket, it was able to substantially undercut the competition, since, in Germany, state tax was levied by the number of sockets. However, reliability was compromised, and production costs for the tube were much greater. In a sense, these were akin to integrated circuits. In the United States, Cleartron briefly produced the "Multivalve" triple triode for use in the Emerson Baby Grand receiver. This Emerson set also has a single tube socket, but because it uses a four-pin base, the additional element connections are made on a "mezzanine" platform at the top of the tube base.\n\nBy 1940 multisection tubes had become commonplace. There were constraints, however, due to patents and other licensing considerations (see [[British Valve Association]]). Constraints due to the number of external pins (leads) often forced the functions to share some of those external connections such as their cathode connections (in addition to the heater connection). The RCA Type 55 is a [[double diode triode]] used as a detector, [[automatic gain control]] rectifier and audio [[preamplifier]] in early AC powered radios. These sets often include the 53 Dual Triode Audio Output. Another early type of multi-section tube, the [[6SN7]], is a "dual triode" which performs the functions of two triode tubes while taking up half as much space and costing less.\nThe [[12AX7]] is a dual "high mu" (high voltage gain<ref>{{cite book |last=Baker |first=Bonnie |title=Analog circuits |date=2008 |page=391 |publisher=Newnes |isbn=978-0-7506-8627-3}}</ref><ref>{{cite web |url=http://v\u00e4lljud.se/index.php/tilbehoer/ram-labs/mu-gm-and-rp-and-how-tubes-are-matched |title=Mu, Gm and Rp and how Tubes are matched |last=Modjeski |first=Roger A. |publisher=V\u00e4lljud AB |access-date=22 April 2011 |url-status=dead |archive-url=https://web.archive.org/web/20120321012946/http://xn--vlljud-bua.se/index.php/tilbehoer/ram-labs/mu-gm-and-rp-and-how-tubes-are-matched |archive-date=21 March 2012 }}</ref><ref>{{cite book |last=Ballou |first=Glen |author-link=Glen Ballou |title=Handbook for Sound Engineers: The New Audio Cyclopedia |url=https://archive.org/details/handbookforsound00ball_195 |url-access=limited |publisher=Howard W. Sams Co. |date=1987 |edition=1st |page=[https://archive.org/details/handbookforsound00ball_195/page/n265 250] |isbn=978-0-672-21983-2 |quote=''Amplification factor or voltage gain'' is the amount the signal at the control grid is increased in amplitude after passing through the tube, which is also referred to as the Greek letter \u03bc (mu) or voltage gain (V<sub>g</sub>) of the tube.}}</ref>) triode in a miniature enclosure, and became widely used in audio signal amplifiers, instruments, and [[guitar amplifier]]s.\n\nThe introduction of the miniature tube base (see below) which can have 9 pins, more than previously available, allowed other multi-section tubes to be introduced, such as the [[6GH8]]/ECF82 triode-pentode, quite popular in television receivers. The desire to include even more functions in one envelope resulted in the General Electric [[Compactron]] which has 12 pins. A typical example, the 6AG11, contains two triodes and two diodes.\n\nSome otherwise conventional tubes do not fall into standard categories; the 6AR8, 6JH8 and 6ME8 have several common grids, followed by a pair of [[Beam deflection tube|beam deflection]] electrodes which deflected the current towards either of two anodes. They were sometimes known as the 'sheet beam' tubes and used in some color TV sets for [[Chrominance|color]] [[Analog television#Color video signal extraction|demodulation]]. The similar 7360 was popular as a balanced [[Single-sideband modulation|SSB]] [[Product detector|(de)modulator]].\n\n {{Main|Beam tetrode}}\n[[File:Eimac.jpg|thumb|150px|Beam power tube designed for radio frequency use]]\nA beam power tube forms the electron stream from the cathode into multiple [[collimated beam|partially collimated beams]] to produce a low potential [[space charge]] region between the anode and screen grid to return anode [[secondary emission]] electrons to the anode when the anode potential is less than that of the screen grid.<ref>Donovan P. Geppert, (1951). [https://www.nvhrbiblio.nl/biblio/boek/Geppert%20-%20Basic%20electron%20tubes.pdf ''Basic Electron Tubes''], New York: McGraw-Hill, pp. 164 - 179. Retrieved 10 June 2021</ref><ref>Winfield G. Wagener, (May 1948). [https://worldradiohistory.com/Archive-IRE/40s/IRE-1948-05.pdf "500-Mc. Transmitting Tetrode Design Considerations"] ''Proceedings of the I.R.E.'', p. 612. Retrieved 10 June 2021</ref> Formation of beams also reduces screen grid current. In some cylindrically symmetrical beam power tubes, the cathode is formed of narrow strips of emitting material that are aligned with the apertures of the control grid, reducing control grid current.<ref>Staff, (2003). [https://www.cpii.com/docs/related/22/C&F2Web.pdf ''Care and Feeding of Power Grid Tubes''], San Carlos, CA: CPI, EIMAC Div., p. 28</ref> This design helps to overcome some of the practical barriers to designing high-power, high-efficiency power tubes.\n\nManufacturer's data sheets often use the terms ''beam pentode'' or ''beam power pentode'' instead of ''beam power tube'', and use a pentode graphic symbol instead of a graphic symbol showing beam forming plates.<ref>GE Electronic Tubes, (March 1955) [https://frank.pocnet.net/sheets/093/6/6V6GT.pdf ''6V6GT - 5V6GT Beam Pentode''], Schenectady, NY: Tube Division, General Electric Co.</ref>\n\nBeam power tubes offer the advantages of a longer load line, less screen current, higher transconductance and lower third harmonic distortion than comparable power pentodes.<ref>J. F. Dreyer, Jr., (April 1936). [https://worldradiohistory.com/Archive-Electronics/30s/Electronics-1936-04.pdf "The Beam Power Output Tube"], ''Electronics'', Vol. 9, No. 4, pp. 18 - 21, 35</ref><ref>R. S. Burnap (July 1936). [https://worldradiohistory.com/ARCHIVE-RCA/RCA-Review/RCA-Review-1936-Jul.pdf "New Developments in Audio Power Tubes"], ''RCA Review'', New York: RCA Institutes Technical Press, pp. 101 - 108</ref> Beam power tubes can be connected as triodes for improved audio tonal quality but in triode mode deliver significantly reduced power output.<ref>\nRCA, (1954). [https://frank.pocnet.net/sheets/049/6/6L6.pdf ''6L6, 6L6-G Beam Power Tube'']. Harrison, NJ: Tube Division, RCA. pp. 1,2,6</ref>\n\n [[Gas-filled tube]]s such as [[discharge tube]]s and [[cold cathode]] tubes are not ''hard'' vacuum tubes, though are always filled with gas at less than sea-level atmospheric pressure. Types such as the [[voltage-regulator tube]] and [[thyratron]] resemble hard vacuum tubes and fit in sockets designed for vacuum tubes. Their distinctive orange, red, or purple glow during operation indicates the presence of gas; electrons flowing in a vacuum do not produce light within that region. These types may still be referred to as "electron tubes" as they do perform electronic functions. High-power rectifiers use [[mercury (element)|mercury]] vapor to achieve a lower forward voltage drop than high-vacuum tubes.\n\n [[File:Vacuum tubes octal, miniature.agr.jpg|thumb|upright|150px|Miniature tube (right) compared to the older octal style. Not including pins, the larger tube, a 5U4GB, is {{nowrap|93 mm}} high with a {{nowrap|35 mm}} diameter base, while the smaller, a 9-pin [[12AX7]], is {{nowrap|45 mm}} high, and {{nowrap|20.4 mm}} in diameter.]]\n[[File:CV4501.JPG|thumb|right|150px|Subminiature CV4501 tube (SQ version of EF72), {{nowrap|35 mm long}} x {{nowrap|10 mm diameter}} (excluding leads)]]\n\nEarly tubes used a metal or glass envelope atop an insulating [[bakelite]] base. In 1938 a technique was developed to use an all-glass construction<ref>C H Gardner (1965) [http://www.r-type.org/articles/art-001.htm The Story of the Valve] {{webarchive|url=https://web.archive.org/web/20151223164546/http://www.r-type.org/articles/art-001.htm |date=23 December 2015}}, Radio Constructor (See particularly the section "Glass Base Construction")</ref> with the pins fused in the glass base of the envelope. This was used in the design of a much smaller tube outline, known as the miniature tube, having seven or nine pins. Making tubes smaller reduced the voltage where they could safely operate, and also reduced the power dissipation of the filament. Miniature tubes became predominant in consumer applications such as radio receivers and hi-fi amplifiers. However, the larger older styles continued to be used especially as higher-power [[rectifier]]s, in higher-power audio output stages and as transmitting tubes.\n\n [[File:6DS4NuvistorVacuumTube.jpg|thumb|right|120px|upright|RCA 6DS4 "Nuvistor" triode, c. {{nowrap|20 mm high}} by {{nowrap|11 mm diameter}}]]\n\nSub-miniature tubes with a size roughly that of half a cigarette were used in one of the very earliest general-purpose [[digital computers]], the Jaincomp-B, produced by the Jacobs Instrument Company,<ref name=symp>[http://www.ed-thelen.org/comp-hist/Computers-1952-hand.html Pentagon symposium: ''Commercially Available General Purpose Electronic Digital Computers of Moderate Price'', Washington, D.C., 14 MAY 1952]</ref>{{efn|The Jaincomp-B was just {{sfrac|8|1|2}}\u2033 \u00d7 {{sfrac|21|1|4}}\u2033 \u00d7 30\u2033 and weighed only 110 lbs, but contained 300 subminiature vacuum tubes and offered performance on a par with then-common building-sized digital computers.<ref name=symp/>}} and consumer applications as hearing-aid amplifiers. These tubes did not have pins plugging into a socket but were soldered in place. The "[[acorn tube]]" (named due to its shape) was also very small, as was the metal-cased RCA [[nuvistor]] from 1959, about the size of a [[thimble]]. The nuvistor was developed to compete with the early transistors and operated at higher frequencies than those early transistors could. The small size supported especially high-frequency operation; nuvistors were used in aircraft radio transceivers, [[Ultra high frequency|UHF]] television tuners, and some HiFi FM radio tuners (Sansui 500A) until replaced by high-frequency capable transistors.\n\n [[File:Vacuum Tube Commercial Packages.png|thumb|Commercial packaging for vacuum tubes used in the latter half of the 20th century including boxes for individual tubes (bottom right), sleeves for rows of the boxes (left), and bags that smaller tubes would be put in by a store upon purchase (top right)]]\n\nThe earliest vacuum tubes strongly resembled incandescent light bulbs and were made by lamp manufacturers, who had the equipment needed to manufacture glass envelopes and the [[vacuum pump]]s required to evacuate the enclosures. de Forest used [[Heinrich Geissler]]'s mercury displacement pump, which left behind a partial [[vacuum]]. The development of the [[diffusion pump]] in 1915 and improvement by [[Irving Langmuir]] led to the development of high-vacuum tubes. After World War I, specialized manufacturers using more economical construction methods were set up to fill the growing demand for broadcast receivers. Bare tungsten filaments operated at a temperature of around 2200 \u00b0C. The development of oxide-coated filaments in the mid-1920s reduced filament [[operating temperature]] to a dull red heat (around 700 \u00b0C), which in turn reduced thermal distortion of the tube structure and allowed closer spacing of tube elements. This in turn improved tube gain, since the gain of a triode is inversely proportional to the spacing between grid and cathode. Bare tungsten filaments remain in use in small transmitting tubes but are brittle and tend to fracture if handled roughly\u2014e.g. in the postal services. These tubes are best suited to stationary equipment where impact and vibration is not present. Over time vacuum tubes became much smaller.\n\n The desire to power electronic equipment using AC mains power faced a difficulty with respect to the powering of the tubes' filaments, as these were also the cathode of each tube. Powering the filaments directly from a [[power transformer]] introduced mains-frequency (50 or 60 Hz) hum into audio stages. The invention of the "equipotential cathode" reduced this problem, with the filaments being powered by a balanced AC power transformer winding having a grounded center tap.\n\nA superior solution, and one which allowed each cathode to "float" at a different voltage, was that of the indirectly heated cathode: a cylinder of oxide-coated nickel acted as an electron-emitting cathode and was electrically isolated from the filament inside it. Indirectly heated cathodes enable the cathode circuit to be separated from the heater circuit. The filament, no longer electrically connected to the tube's electrodes, became simply known as a "heater", and could as well be powered by AC without any introduction of hum.<ref>L.W. Turner (ed.) ''Electronics Engineer's Reference Book'', 4th ed. Newnes-Butterworth, London 1976 {{ISBN|0-408-00168-2}} pages 7\u20132 through 7-6</ref> In the 1930s, indirectly heated cathode tubes became widespread in equipment using AC power. Directly heated cathode tubes continued to be widely used in battery-powered equipment as their filaments required considerably less power than the heaters required with indirectly heated cathodes.\n\nTubes designed for high gain audio applications may have twisted heater wires to cancel out stray electric fields, fields that could induce objectionable hum into the program material.\n\nHeaters may be energized with either alternating current (AC) or direct current (DC). DC is often used where low hum is required.\n\n {{See also|List of vacuum tube computers}}\n[[File:ENIAC Penn2.jpg|thumb|right|300px|The 1946 [[ENIAC]] computer used 17,468 vacuum tubes and consumed {{nowrap|150 kW}} of power]]\n\nVacuum tubes used as switches made electronic computing possible for the first time, but the cost and relatively short [[mean time to failure]] of tubes were limiting factors.<ref>{{Cite journal|last=Guarnieri|first=M.|date=2012|title=The age of Vacuum Tubes: Merging with Digital Computing|journal=IEEE Ind. Electron. M.|volume=6|issue=3|pages=52\u201355|doi=10.1109/MIE.2012.2207830|s2cid=41800914}}</ref> "The common wisdom was that valves\u2014which, like light bulbs, contained a hot glowing filament\u2014could never be used satisfactorily in large numbers, for they were unreliable, and in a large installation too many would fail in too short a time".<ref name=colossus/> [[Tommy Flowers]], who later designed ''[[Colossus computer|Colossus]]'', "discovered that, so long as valves were switched on and left on, they could operate reliably for very long periods, especially if their 'heaters' were run on a reduced current".<ref name=colossus>[http://www.colossus-computer.com/colossus1.html#section02 From part of Copeland's "Colossus" available online] {{webarchive|url=https://web.archive.org/web/20120323055457/http://www.colossus-computer.com/colossus1.html |date=23 March 2012 }}</ref> In 1934 Flowers built a successful experimental installation using over 3,000 tubes in small independent modules; when a tube failed, it was possible to switch off one module and keep the others going, thereby reducing the risk of another tube failure being caused; this installation was accepted by the [[General Post Office|Post Office]] (who operated telephone exchanges). Flowers was also a pioneer of using tubes as very fast (compared to electromechanical devices) [[Switch#Electronic switches|electronic switches]]. Later work confirmed that tube unreliability was not as serious an issue as generally believed; the 1946 [[ENIAC]], with over 17,000 tubes, had a tube failure (which took 15 minutes to locate) on average every two days. The quality of the tubes was a factor, and the diversion of skilled people during the Second World War lowered the general quality of tubes.<ref>{{cite web|url=http://www.computerworld.com/printthis/2006/0,4814,108568,00.html|title=A lost interview with ENIAC co-inventor J. Presper Eckert|first=Alexander 5th|last=Randall|publisher=Computer World|date=14 February 2006|access-date=2011-04-25|url-status=live|archive-url=https://web.archive.org/web/20090402143001/http://www.computerworld.com/printthis/2006/0,4814,108568,00.html|archive-date=2 April 2009}}</ref> During the war Colossus was instrumental in breaking German codes. After the war, development continued with tube-based computers including, military computers [[ENIAC]] and [[Whirlwind (computer)|Whirlwind]], the [[Ferranti Mark 1]] (one of the first commercially available electronic computers), and [[UNIVAC I]], also available commercially.\n\nAdvances using subminiature tubes included the Jaincomp series of machines produced by the Jacobs Instrument Company of Bethesda, Maryland.  Models such as its Jaincomp-B employed just 300 such tubes in a desktop-sized unit that offered performance to rival many of the then room-sized machines.<ref name=symp/>\n\n {{Main|Colossus computer}}\n[[File:GB-ENG - Bletchley - Computers - Buckinghamshire - Milton Keynes - Bletchly - Bletchley Park (4890148011).jpg|thumb|Vacuum tubes seen on end in a recreation of the World War II-era [[Colossus computer]] at [[Bletchley Park]], England]]\n\nFlowers's Colossus and its successor Colossus Mk2 were built by the British during World War II to substantially speed up the task of breaking the German high level [[Lorenz cipher|Lorenz encryption]]. Using about 1,500 vacuum tubes (2,400 for Mk2), Colossus replaced an earlier machine based on relay and switch logic (the [[Heath Robinson (codebreaking machine)|Heath Robinson]]). Colossus was able to break in a matter of hours messages that had previously taken several weeks; it was also much more reliable.<ref name=colossus/> Colossus was the first use of vacuum tubes ''working in concert'' on such a large scale for a single machine.<ref name=colossus/>\n\nOnce Colossus was built and installed, it ran continuously, powered by dual redundant diesel generators, the wartime mains supply being considered too unreliable. The only time it was switched off was for conversion to Mk2, which added more tubes. Another nine Colossus Mk2s were built. Each Mk2 consumed 15 kilowatts; most of the power was for the tube heaters.\n\nA Colossus reconstruction was switched on in 1996; it was upgraded to Mk2 configuration in 2004; it found the key for a wartime German [[ciphertext]] in 2007.<ref>{{multiref\n|[http://www.tnmoc.org/special-projects/colossus-rebuild/rebuilding-colossus The National Museum of Computing\u2014Rebuilding Colossus]\n|[http://www.tnmoc.org/explore/colossus-gallery The National Museum of Computing\u2014The Colossus Gallery]}}</ref>\n\n {{Main|Whirlwind (computer)}}\n[[File:8863-Project-Whirlwind-CRMI.JPG|thumb|Circuitry from core memory unit of [[Whirlwind I|Whirlwind]] ]]\n\nTo meet the reliability requirements of the 1951 US digital computer Whirlwind, "special-quality" tubes with extended life, and a long-lasting cathode in particular, were produced. The problem of short lifetime was traced largely to evaporation of [[silicon]], used in the [[tungsten]] alloy to make the heater wire easier to draw.  The silicon forms [[barium orthosilicate]] at the interface between the nickel sleeve and the cathode [[barium oxide]] coating.<ref name=Jones>Morgan Jones, ''Valve Amplifiers'', Elsevier, 2012 {{ISBN|0080966403}}.</ref>{{rp|301}}  This "cathode interface" is a high-resistance layer (with some parallel capacitance) which greatly reduces the cathode current when the tube is switched into conduction mode.<ref name=RichTaylor/>{{rp|224}}  Elimination of silicon from the heater wire alloy (and more frequent replacement of the [[wire]] drawing [[Die (manufacturing)#Wire pulling|dies]]) allowed the production of tubes that were reliable enough for the Whirlwind project.  High-purity nickel tubing and cathode coatings free of materials such as [[silicate]]s and aluminum that can reduce emissivity also contribute to long cathode life.\n\nThe first such "computer tube" was Sylvania's [[7AK7]] pentode of 1948 (these replaced the 7AD7, which was supposed to be better quality than the standard 6AG7 but proved too unreliable).<ref name=Ulmann/>{{rp|59}} Computers were the first tube devices to run tubes at cutoff (enough negative grid voltage to make them cease conduction) for quite-extended periods of time.  Running in cutoff with the heater on accelerates cathode poisoning and the output current of the tube will be greatly reduced when switched into conduction mode.<ref name=RichTaylor/>{{rp|224}} The 7AK7 tubes improved the cathode poisoning problem, but that alone was insufficient to achieve the required reliability.<ref name=Ulmann/>{{rp|60}} Further measures included switching off the heater voltage when the tubes were not required to conduct for extended periods, turning on and off the heater voltage with a slow ramp to avoid [[thermal shock]] on the heater element,<ref name= RichTaylor>E.S. Rich, N.H. Taylor, "Component failure analysis in computers", ''Proceedings of Symposium on Improved Quality Electronic Components'', vol. 1, pp. 222\u2013233, Radio-Television Manufacturers Association, 1950.</ref>{{rp|226}} and [[Hardware stress test|stress test]]ing the tubes during offline maintenance periods to bring on early failure of weak units.<ref name=Ulmann>Bernd Ulmann, ''AN/FSQ-7: The Computer that Shaped the Cold War'', Walter de Gruyter GmbH, 2014 {{ISBN|3486856707}}.</ref>{{rp|60\u201361}}\n\nThe tubes developed for Whirlwind were later used in the giant [[Semi Automatic Ground Environment|SAGE]] air-defense computer system. By the late 1950s, it was routine for special-quality small-signal tubes to last for hundreds of thousands of hours if operated conservatively. This increased reliability also made mid-cable amplifiers in [[Submarine communications cable|submarine cable]]s possible."}},
{"article_title": "Vacuum pump", "pageid": "32500", "revid": "1057209977", "timestamp": "2021-11-26T04:54:37Z", "history_paths": [["Vacuum pump --- Introduction ---", "History"]], "categories": ["vacuum pumps", "vacuum systems", "pumps", "vacuum", "1642 introductions", "gas technologies", "german inventions", "17th-century inventions"], "heading_tree": {"Vacuum pump --- Introduction ---": {"History": {"Early pumps": {}, "19th century": {}, "20th century": {}}, "Types": {"Positive displacement pump": {}, "Momentum transfer pump": {}, "Regenerative pump": {}, "Entrapment pump": {}, "Other types": {}}, "Performance measures": {}, "Techniques": {}, "Applications": {}, "Hazards": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Vacuum pump --- Introduction ---|History": "The predecessor to the vacuum [[pump]] was the [[suction pump]]. Dual-action suction pumps were found in the city of [[Pompeii]].<ref>{{cite web|url=http://www.imss.fi.it/pompei/tecnica/epompa.html|title=Pompeii: Technology: Working models: IMSS}}</ref> Arabic engineer [[Al-Jazari]] later described dual-action suction pumps as part of water-raising machines in the 13th century. He also said that a suction pump was used in [[siphons]] to discharge [[Greek fire]].<ref name="Hill" /> The suction pump later appeared in medieval Europe from the 15th century.<ref name="Hill">[[Donald Routledge Hill]] (1996), ''A History of Engineering in Classical and Medieval Times'', [[Routledge]], pp. 143 & 150-2</ref><ref name=Hill2>[[Donald Routledge Hill]], "Mechanical Engineering in the Medieval Near East", ''Scientific American'', May 1991, pp. 64-69 ([[cf.]] [[Donald Routledge Hill]], [https://web.archive.org/web/20110101193750/http://home.swipnet.se/islam/articles/HistoryofSciences.htm Mechanical Engineering])</ref><ref>{{cite web|author=Ahmad Y Hassan |title=The Origin of the Suction Pump: Al-Jazari 1206 A.D |url=http://www.history-science-technology.com/Notes/Notes%202.htm |access-date=2008-07-16 |author-link=Ahmad Y Hassan |url-status=dead |archive-url=https://web.archive.org/web/20080226102543/http://www.history-science-technology.com/Notes/Notes%202.htm |archive-date=February 26, 2008 }}</ref>\n\n[[File:Molchanova by levitskiy.jpg|thumb|Student of [[Smolny Institute]] Catherine Molchanova with vacuum pump, by [[Dmitry Levitzky]], 1776]]\nBy the 17th century, water pump designs had improved to the point that they produced measurable vacuums, but this was not immediately understood. What was known was that suction pumps could not pull water beyond a certain height: 18 Florentine yards according to a measurement taken around 1635, or about {{Convert|34|ft|m}}.<ref name=":0">{{cite book|last=Gillispie|first=Charles Coulston|url=https://archive.org/details/edgeofobjectivit00char|title=The Edge of Objectivity: An Essay in the History of Scientific Ideas|publisher=Princeton University Press|year=1960|isbn=0-691-02350-6|location=Princeton, NJ|pages=99\u2013100|author-link=Charles Coulston Gillispie}}</ref> This limit was a concern in irrigation projects, mine drainage, and decorative water fountains planned by the Duke of [[Tuscany]], so the duke commissioned [[Galileo Galilei]] to investigate the problem. Galileo suggests incorrectly in his ''[[Two New Sciences]]'' (1638) that the column of a water pump will break of its own weight when the water has been lifted to 34 feet.<ref name=":0" /> Other scientists took up the challenge, including [[Gasparo Berti]], who replicated it by building the first water barometer in Rome in 1639.<ref>{{cite web |url=http://www.denmark.com.au/en/Worlds+Largest+Barometer/default.htm |archive-url=https://web.archive.org/web/20080216140317/http://www.denmark.com.au/en/Worlds+Largest+Barometer/default.htm |archive-date=2008-02-16 |title=The World's Largest Barometer |access-date=2008-04-30 }}</ref> Berti's barometer produced a vacuum above the water column, but he could not explain it. A breakthrough was made by Galileo's student [[Evangelista Torricelli]] in 1643. Building upon Galileo's notes, he built the first [[Mercury (element)|mercury]] [[barometer]] and wrote a convincing argument that the space at the top was a vacuum. The height of the column was then limited to the maximum weight that atmospheric pressure could support; this is the limiting height of a suction pump.<ref>{{Harv|Calvert|2000|loc="[http://mysite.du.edu/~jcalvert/tech/fluids/hydstat.htm#Maxh Maximum height to which water can be raised by a suction pump]"}}</ref>\n\nIn 1650, [[Otto von Guericke]] invented the first vacuum pump.<ref>{{Cite journal|last=Harsch|first=Viktor|date=November 2007|title=Otto von Gericke (1602\u20131686) and his pioneering vacuum experiments|url=https://pubmed.ncbi.nlm.nih.gov/18018443/|journal=Aviation, Space, and Environmental Medicine|volume=78|issue=11|pages=1075\u20131077|doi=10.3357/asem.2159.2007|issn=0095-6562|pmid=18018443}}</ref> Four years later, he conducted his famous [[Magdeburg hemispheres]] experiment, showing that teams of horses could not separate two hemispheres from which the air had been evacuated. [[Robert Boyle]] improved Guericke's design and conducted experiments on the properties of vacuum. [[Robert Hooke]] also helped Boyle produce an air pump that helped to produce the vacuum.\n\n [[Image:HiVacuumApparatus-Tesla.png|thumb|333px|Tesla's vacuum apparatus, published in 1892]]\nThe study of vacuum then lapsed{{Dubious|date=September 2011}} until 1855, when [[Heinrich Geissler]] invented the mercury displacement pump and achieved a record vacuum of about 10 Pa (0.1 [[Torr]]). A number of electrical properties become observable at this vacuum level, and this renewed interest in vacuum. This, in turn, led to the development of the [[vacuum tube]]. The [[Sprengel pump]] was a widely used vacuum producer of this time.\n\n The early 20th century saw the invention of many types of vacuum pump, including the [[molecular drag pump]], the [[diffusion pump]], and the [[turbomolecular pump]]."}},
{"article_title": "V-chip", "pageid": "32586", "revid": "1062189301", "timestamp": "2021-12-26T22:30:57Z", "history_paths": [["V-chip --- Introduction ---", "History"]], "categories": ["censorship of broadcasting", "media content ratings systems", "television technology", "parenting"], "heading_tree": {"V-chip --- Introduction ---": {"History": {}, "Implementation": {}, "Forces leading to development": {"Scientific-technical": {}, "Political": {}}, "The Telecommunications Act": {}, "Ratings": {}, "Invention and patent": {"Invention": {}, "Patent": {}}, "Criticisms": {"Usage": {}, "Lack of supporting research": {}, "Expenses": {}, "Infringement on rights": {}, "Insufficient number of users": {}}, "Support": {"Parental responsibility": {}, "Expenses": {}, "Ease of monitoring for parents": {}, "Support from PTA groups": {}}, "The V-chip and commercials": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"V-chip --- Introduction ---|History": "In 1975, the [[Family Viewing Hour]] was introduced in the United States, in which broadcasters had to play TV content suitable for all ages. This idea was quickly abandoned because broadcasters felt it violated their [[First Amendment to the United States Constitution|First Amendment]] rights by restricting what content they could play. The inventor of the V-chip technology originally meant for it to be a simple tool that parents could use to restrict their children's television viewing. He did not expect it would become a national standard for all televisions.<ref name="INT1">{{cite web | url = http://library.thinkquest.org/5676/collings.html | title = Interview with Mr. Tim Collings | access-date = 2010-06-23 | url-status = dead | archive-url = https://web.archive.org/web/20091003035634/http://library.thinkquest.org/5676/collings.html | archive-date = 2009-10-03 }}</ref>"}},
{"article_title": "World Wide Web", "pageid": "33139", "revid": "1062422913", "timestamp": "2021-12-28T10:21:57Z", "history_paths": [["World Wide Web --- Introduction ---", "History"]], "categories": ["world wide web", "computer-related introductions in 1989", "english inventions", "british inventions", "human\u2013computer interaction", "information age", "cern", "tim berners-lee", "web technology", "20th-century inventions"], "heading_tree": {"World Wide Web --- Introduction ---": {"History": {}, "Function": {"HTML": {}, "Linking": {}, "WWW prefix": {}, "Scheme specifiers": {}, "Pages": {"Static page": {}, "Dynamic pages": {}}, "Website": {}, "Browser": {}, "Server": {}, "Cookie": {}, "Search engine": {}, "Deep web": {}, "Caching": {}}, "Security": {}, "Privacy": {}, "Standards": {}, "Accessibility": {}, "Internationalisation": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"World Wide Web --- Introduction ---|History": "{{Main|History of the World Wide Web}}\n[[File:NeXTcube first webserver.JPG|thumb|The [[NeXT Computer]] used by [[Tim Berners-Lee]] at [[CERN]]]]\n[[File:CERN web corridor.jpg|thumb|The corridor where WWW (or World Wide Web) was born. [[CERN]], the ground floor of building No. 1]]\n\nThe underlying concept of hypertext originated in previous projects from the 1960s, such as the [[Hypertext Editing System]] (HES) at Brown University, [[Ted Nelson]]'s [[Project Xanadu]], and [[Douglas Engelbart]]'s [[NLS (computer system)|oN-Line System]] (NLS). Both Nelson and Engelbart were in turn inspired by [[Vannevar Bush]]'s [[microfilm]]-based ''[[memex]]'', which was described in the 1945 essay "[[As We May Think]]".<ref name="Conkling">{{Citation |last=Conklin |first=Jeff |title=IEEE Computer |volume=20 |issue=9 |pages=17\u201341 |publication-date=1987 |year=1987}}.</ref>  [[Tim Berners-Lee]]'s vision of a global hyperlinked information system became a possibility by the second half of the 1980s.<ref>{{Cite web |url=https://www.mwdwebsites.com/nj-web-design-world-wide-web.html |title=The Evolution of the World Wide Web |last=Enzer |first=Larry |date=31 August 2018 |website=Monmouth Web Developers |access-date=31 August 2018 |archive-url=https://web.archive.org/web/20181118231641/https://www.mwdwebsites.com/nj-web-design-world-wide-web.html |archive-date=18 November 2018 |url-status=dead}}</ref> By 1985, the [[Global Internet usage|global Internet]] began to proliferate in Europe and the [[Domain Name System]] (upon which the [[Uniform Resource Locator]] is built) came into being. In 1988 the first direct IP connection between Europe and North America was made and Berners-Lee began to openly discuss the possibility of a web-like system at CERN.<ref>{{cite web |url=http://cs.wellesley.edu/~cs315/BOOKS/TBL12.pdf |title=Archived copy |access-date=2015-08-26 |url-status=dead |archive-url=https://web.archive.org/web/20151117022333/http://cs.wellesley.edu/~cs315/BOOKS/TBL12.pdf |archive-date=17 November 2015}}</ref>\n\nWhile working at CERN, Berners-Lee became frustrated with the inefficiencies and difficulties posed by finding information stored on different computers.<ref>{{Cite news |url=https://www.usatoday.com/story/tech/news/2019/03/12/world-wide-web-turns-30-berners-lee-contract-thoughts-internet/3137726002/ |title=Happy 30th birthday, World Wide Web. Inventor outlines plan to combat hacking, hate speech |last=May  |first=Ashley |date=12 March 2019 |work=USA Today |access-date=2019-03-12 |language=en}}</ref> On 12 March 1989, he submitted a memorandum, titled "Information Management: A Proposal",<ref>{{cite news |url=https://www.vox.com/2019/3/12/18260709/30th-anniversary-of-the-world-wide-web-google-doodle-history |title=The World Wide Web \u2013 not the Internet \u2013 turns 30 years old |work=Vox.com |author=Aja Romano |date=12 March 2019}}</ref> to the management at CERN for a system called "Mesh" that referenced [[ENQUIRE]], a database and software project he had built in 1980, which used the term "web" and described a more elaborate information management system based on links embedded as text: "Imagine, then, the references in this document all being associated with the [[network address]] of the thing to which they referred, so that while reading this document, you could skip to them with a click of the mouse." Such a system, he explained, could be referred to using one of the existing meanings of the word ''[[hypertext]]'', a term that he says was coined in the 1950s. There is no reason, the proposal continues, why such hypertext links could not encompass multimedia documents including graphics, speech and video, so that Berners-Lee goes on to use the term ''[[hypermedia]]''.<ref>{{cite web |last=Berners-Lee |first=Tim |url=http://w3.org/History/1989/proposal.html |date=March 1989 |title=Information Management: A Proposal |publisher=W3C |access-date=27 July 2009 |url-status=live |archive-url=https://web.archive.org/web/20090315161300/http://www.w3.org/History/1989/proposal.html |archive-date=15 March 2009}}</ref>\n\nWith help from his colleague and fellow hypertext enthusiast [[Robert Cailliau]] he published a more formal proposal on 12 November 1990 to build a "Hypertext project" called "WorldWideWeb" (one word, abbreviated "W3") as a "web" of "hypertext documents" to be viewed by "[[Web browser|browsers]]" using a [[client\u2013server architecture]].<ref name="W90">{{cite web |url=http://w3.org/Proposal.html |title=WorldWideWeb: Proposal for a HyperText Project |first1=Tim |last1=Berners-Lee |author-link1=Tim Berners-Lee |first2=Robert |last2=Cailliau |author-link2=Robert Cailliau |date=12 November 1990 |access-date=12 May 2015 |url-status=live|archive-url=https://web.archive.org/web/20150502080527/http://www.w3.org/Proposal.html |archive-date=2 May 2015}}</ref><ref name=NYT21>[https://www.nytimes.com/2021/01/10/technology/tim-berners-lee-privacy-internet.html He Created the Web. Now He\u2019s Out to Remake the Digital World], [[New York Times]], by Steve Lohr, 10 Jan 2021.</ref> At this point HTML and [[Hypertext Transfer Protocol|HTTP]] had already been in development for about two months and the first Web server was about a month from completing its first successful test. This proposal estimated that a read-only web would be developed within three months and that it would take six months to achieve "the creation of new links and new material by readers, [so that] authorship becomes universal" as well as "the automatic notification of a reader when new material of interest to him/her has become available". While the read-only goal was met, accessible authorship of web content took longer to mature, with the [[wiki]] concept, [[WebDAV]], [[blog]]s, [[Web 2.0]] and [[RSS]]/[[Atom (standard)|Atom]].<ref>{{cite web |url=http://info.cern.ch/NextBrowser.html |title=Tim Berners-Lee's original World Wide Web browser |quote=With recent phenomena like blogs and wikis, the Web is beginning to develop the kind of collaborative nature that its inventor envisaged from the start. |url-status=live |archive-url=https://web.archive.org/web/20110717031115/http://info.cern.ch/NextBrowser.html |archive-date=17 July 2011}}</ref>\n[[File:Cern datacenter.jpg|thumb|The CERN [[data center|data centre]] in 2010 housing some WWW servers]]\nThe proposal was modelled after the [[SGML]] reader [[Dynatext]] by Electronic Book Technology, a spin-off from the [[Institute for Research in Information and Scholarship]] at [[Brown University]]. The Dynatext system, licensed by [[CERN]], was a key player in the extension of SGML ISO 8879:1986 to Hypermedia within [[HyTime]], but it was considered too expensive and had an inappropriate licensing policy for use in the general high energy physics community, namely a fee for each document and each document alteration.{{citation needed|date=March 2019}} A [[NeXT Computer]] was used by Berners-Lee as the world's first [[web server]] and also to write the first [[web browser]] in 1990. By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web:<ref>{{cite web |url=http://w3.org/People/Berners-Lee/WorldWideWeb |title=Tim Berners-Lee: client |publisher=W3.org |access-date=27 July 2009 |url-status=live |archive-url=https://web.archive.org/web/20090721113108/http://www.w3.org/People/Berners-Lee/WorldWideWeb |archive-date=21 July 2009}}</ref> the first web browser ([[WorldWideWeb]], which was a [[HTML editor|web editor]] as well) and the first web server. The first website,<ref>{{cite web |url=http://w3.org/History/19921103-hypertext/hypertext/WWW/TheProject.html |title=First Web pages |publisher=W3.org |access-date=27 July 2009 |url-status=live |archive-url=https://web.archive.org/web/20100131201408/http://www.w3.org/History/19921103-hypertext/hypertext/WWW/TheProject.html |archive-date=31 January 2010}}</ref> which described the project itself, was published on 20 December 1990.<ref>{{cite web |url=http://home.cern/topics/birth-web |title=The birth of the web |publisher=CERN |access-date=23 December 2015 |url-status=live |archive-url=https://web.archive.org/web/20151224103843/http://home.cern/topics/birth-web |archive-date=24 December 2015}}</ref>\n\nThe first web page may be lost, but [[Paul Jones (computer technologist)|Paul Jones]] of [[UNC-Chapel Hill]] in North Carolina announced in May 2013 that Berners-Lee gave him what he says is the oldest known web page during a visit to [[University of North Carolina|UNC]] in 1991. Jones stored it on a [[magneto-optical drive]] and his NeXT computer.<ref>{{cite news |title=Hunt for world's oldest WWW page leads to UNC-Chapel Hill |url=http://www.newsobserver.com/2013/05/24/2915835/hunt-for-worlds-oldest-www-page.html |last=Murawski |first=John |work=[[News & Observer]] |date=24 May 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130608011200/http://www.newsobserver.com/2013/05/24/2915835/hunt-for-worlds-oldest-www-page.html |archive-date=8 June 2013}}</ref> On 6 August 1991, Berners-Lee published a short summary of the World Wide Web project on the [[newsgroup]] ''alt.hypertext''.<ref>{{cite web |url=http://groups.google.com/group/alt.hypertext/msg/395f282a67a1916c |title=Short summary of the World Wide Web project |date=6 August 1991 |access-date=27 July 2009}}</ref> This date is sometimes confused with the public availability of the first web servers, which had occurred months earlier. As another example of such confusion, some news media reported that the first photo on the Web was published by Berners-Lee in 1992, an image of the CERN house band [[Les Horribles Cernettes]] taken by Silvano de Gennaro; Gennaro has disclaimed this story, writing that media were "totally distorting our words for the sake of cheap sensationalism".<ref>{{cite web |title=Silvano de Gennaro disclaims 'the first photo on the Web'|url=http://musiclub.web.cern.ch/MusiClub/bands/cernettes/disclaimer.html |quote=If you read well our website, it says that it was, to our knowledge, the 'first photo of a band'. Dozens of media are totally distorting our words for the sake of cheap sensationalism. Nobody knows which was the first photo on the Web. |access-date=27 July 2012 |url-status=live |archive-url=https://web.archive.org/web/20120804062915/http://musiclub.web.cern.ch/MusiClub/bands/cernettes/disclaimer.html |archive-date=4 August 2012}}</ref>\n\nThe first server outside Europe was installed in December 1991 at the [[SLAC National Accelerator Laboratory|Stanford Linear Accelerator Center]] (SLAC) in Palo Alto, California, to host the [[SPIRES]]-HEP database.<ref>{{cite web |url=http://www.slac.stanford.edu/history/earlyweb/history.shtml |title=The Early World Wide Web at SLAC |url-status=live |archive-url=https://web.archive.org/web/20051124035516/http://www.slac.stanford.edu/history/earlyweb/history.shtml |archive-date=24 November 2005}}</ref><ref>{{cite web |url=http://slac.stanford.edu/spires/about/ |title=About SPIRES |access-date=30 March 2010 |url-status=live |archive-url=https://web.archive.org/web/20100212023810/http://www.slac.stanford.edu/spires/about/ |archive-date=12 February 2010}}</ref><ref>{{cite web |url=http://www.w3.org/History.html |title=A Little History of the World Wide Web |url-status=live |archive-url=https://web.archive.org/web/20130506021750/http://www.w3.org/History.html |archive-date=6 May 2013}}</ref><ref>{{cite web |url=http://www.w3.org/2005/01/timelines/description |title=W3C10 Timeline Graphic |access-date=29 January 2020}}</ref>\n\nBerners-Lee's breakthrough was to marry hypertext to the Internet. In his book ''[[Weaving the Web: The Original Design and Ultimate Destiny of the World Wide Web by its inventor|Weaving The Web]]'', he explains that he had repeatedly suggested to members of ''both'' technical communities that a marriage between the two technologies was possible. But, when no one took up his invitation, he finally assumed the project himself. In the process, he developed three essential technologies:\n* a system of globally unique identifiers for resources on the Web and elsewhere, the universal document identifier (UDI), later known as [[uniform resource locator]] (URL) and [[uniform resource identifier]] (URI);\n* the publishing language [[Hypertext Markup Language]] (HTML);\n* the [[Hypertext Transfer Protocol]] (HTTP).<ref>{{cite web |title=Inventor of the Week Archive: The World Wide Web |url=http://web.mit.edu/invent/iow/berners-lee.html |publisher=[[Massachusetts Institute of Technology]]: MIT School of Engineering |access-date=23 July 2009 |archive-url=https://web.archive.org/web/20100608081841/http://web.mit.edu/invent/iow/berners-lee.html |archive-date=8 June 2010}}</ref>\n\nThe World Wide Web had several differences from other hypertext systems available at the time. The Web required only unidirectional links rather than bidirectional ones, making it possible for someone to link to another resource without action by the owner of that resource. It also significantly reduced the difficulty of implementing web servers and browsers (in comparison to earlier systems), but in turn, presented the chronic problem of ''[[link rot]]''. Unlike predecessors such as [[HyperCard]], the World Wide Web was non-proprietary, making it possible to develop servers and clients independently and to add extensions without licensing restrictions. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone, with no fees due.<ref>{{cite web |url=http://tenyears-www.web.cern.ch/tenyears-www/Welcome.html |title=Ten Years Public Domain for the Original Web Software |publisher=Tenyears-www.web.cern.ch |date=30 April 2003 |access-date=27 July 2009 |url-status=live |archive-url=https://web.archive.org/web/20090813032723/http://tenyears-www.web.cern.ch/tenyears-www/Welcome.html |archive-date=13 August 2009}}</ref> Coming two months after the announcement that the server implementation of the [[Gopher (protocol)|Gopher]] protocol was no longer free to use, this produced a rapid shift away from Gopher and toward the Web. An early popular web browser was [[ViolaWWW]] for [[Unix]] and the [[X Window System]].\n[[File:Cailliau Abramatic Berners-Lee 10 years WWW consortium.png|thumb|[[Robert Cailliau]], Jean-Fran\u00e7ois Abramatic, and [[Tim Berners-Lee]] at the tenth anniversary of the World Wide Web Consortium]]\nThe Web began to enter general use in 1993\u20131994, when [[List of websites founded before 1995|websites for everyday use]] started to become available.<ref name=Couldry /> Historians generally agree that a turning point for the Web began with the 1993 introduction of [[Mosaic (web browser)|Mosaic]],<ref>{{cite web |url=http://livinginternet.com/w/wi_mosaic.htm |title=Mosaic Web Browser History \u2013 NCSA, Marc Andreessen, Eric Bina |publisher=Livinginternet.com |access-date=27 July 2009}}</ref><ref>{{cite web |url=http://totic.org/nscp/demodoc/demo.html |title=NCSA Mosaic \u2013 September 10, 1993 Demo |publisher=Totic.org |access-date=27 July 2009}}</ref> a graphical web browser developed at the [[National Center for Supercomputing Applications]] at the [[University of Illinois at Urbana\u2013Champaign]] (NCSA-UIUC). The development was led by [[Marc Andreessen]], while funding came from the US High-Performance Computing and Communications Initiative and the [[High Performance Computing Act of 1991]], one of [[Al Gore and information technology|several computing developments initiated by US Senator Al Gore]].<ref>{{cite web |url=http://cs.washington.edu/homes/lazowska/faculty.lecture/innovation/gore.html |title=Vice President Al Gore's ENIAC Anniversary Speech |publisher=Cs.washington.edu |date=14 February 1996 |access-date=27 July 2009 |url-status=live |archive-url=https://web.archive.org/web/20090220183820/http://www.cs.washington.edu/homes/lazowska/faculty.lecture/innovation/gore.html |archive-date=20 February 2009}}</ref> Before the release of Mosaic, graphics were not commonly mixed with text in web pages, and the Web was less popular than older protocols such as [[Gopher (protocol)|Gopher]] and [[Wide Area Information Servers]] (WAIS). Mosaic's graphical user interface allowed the Web to become by far the most popular protocol on the Internet. The [[World Wide Web Consortium]] (W3C) was founded by Tim Berners-Lee after he left the European Organization for Nuclear Research (CERN) in October 1994. It was founded at the [[Massachusetts Institute of Technology]] Laboratory for Computer Science (MIT/LCS) with support from the [[Defense Advanced Research Projects Agency]] (DARPA), which had pioneered the Internet; a year later, a second site was founded at [[INRIA]] (a French national computer research lab) with support from the [[European Commission]] DG InfSo; and in 1996, a third continental site was created in Japan at [[Keio University]]. By the end of 1994, the total number of websites was still relatively small, but many [[List of websites founded before 1995|notable websites]] were already active that foreshadowed or inspired today's most popular services.\n\nConnected by the Internet, other websites were created around the world. This motivated international standards development for protocols and formatting. Berners-Lee continued to stay involved in guiding the development of web standards, such as the [[markup language]]s to compose web pages and he advocated his vision of a [[Semantic Web]]. The World Wide Web enabled the spread of information over the Internet through an easy-to-use and flexible format. It thus played an important role in popularising use of the Internet.<ref>{{cite journal |last1=Catalano |first1=Charles S. |title=Megaphones to the Internet and the World: The Role of Blogs in Corporate Communications |journal=International Journal of Strategic Communication |date=15 October 2007 |volume=1 |issue=4 |pages=247\u2013262 |doi=10.1080/15531180701623627|s2cid=143156963 }}</ref> Although the two terms are sometimes [[conflation|conflated]] in popular use, ''World Wide Web'' is not [[synonym]]ous with ''Internet''.<ref>{{cite web |url=http://techterms.com/definition/www |title=WWW (World Wide Web) Definition |publisher=TechTerms |access-date=19 February 2010 |url-status=live |archive-url=https://web.archive.org/web/20090511015356/http://www.techterms.com/definition/www |archive-date=11 May 2009}}</ref> The Web is an [[information space]] containing hyperlinked documents and other [[Web resource|resources]], identified by their URIs.<ref>{{cite web |last1=Jacobs |first1=Ian |last2=Walsh |first2=Norman |title=Architecture of the World Wide Web, Volume One |url=http://www.w3.org/TR/webarch/#intro |publisher=W3C |access-date=11 February 2015 |location=Introduction |date=15 December 2004 |url-status=live |archive-url=https://web.archive.org/web/20150209063216/http://www.w3.org/TR/webarch/#intro |archive-date=9 February 2015}}</ref> It is implemented as both client and server software using Internet protocols such as [[TCP/IP]] and [[HTTP]].\n\nBerners-Lee was [[Order of the British Empire|knighted]] in 2004 by Queen [[Elizabeth II]] for "services to the global development of the Internet".<ref name="gaz">{{London Gazette |issue=57155 |para|title=Diplomatic and Overseas List, K.B.E. |date=31 December 2003 |supp=y |page=24}}</ref><ref>{{cite news |title=Web's inventor gets a knighthood |publisher=BBC |date=31 December 2003 |url=http://news.bbc.co.uk/1/hi/technology/3357073.stm |access-date=25 May 2008 |url-status=live |archive-url=https://web.archive.org/web/20071223055131/http://news.bbc.co.uk/1/hi/technology/3357073.stm |archive-date=23 December 2007}}</ref> He never patented his invention."}},
{"article_title": "Wiki software", "pageid": "33164", "revid": "1058105844", "timestamp": "2021-12-01T14:00:27Z", "history_paths": [["Wiki software --- Introduction ---", "History"]], "categories": ["wiki software", "web portals", "information technology management", "wikis by genre"], "heading_tree": {"Wiki software --- Introduction ---": {"History": {}, "Data compatibility": {}, "Types of usage": {"Public wikis": {}, "Enterprise wikis": {}, "Personal wikis": {}}, "Editing": {}, "Hosted application": {}, "Additional features": {"Content-management features": {}, "Scripting": {}, "Semantic annotation": {}, "Mobile access": {}, "Offline viewing and editing": {}, "Distributing and decentralizing": {}}, "See also": {}, "Notes": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Wiki software --- Introduction ---|History": "{{main|History of wikis}}\n\nThe first generally recognized "wiki" application, [[WikiWikiWeb]], was created by American computer programmer [[Ward Cunningham]] in 1994 and launched on c2.com in 1995.<ref>''The Wiki Way. Quick collaboration on the Web'', Addison-Wesley (April 2001) {{ISBN|0-201-71499-X}}</ref> "WikiWikiWeb" was also the name of the wiki that ran on the software, and in the first years of wikis' existence there was no great distinction made between the contents of wikis and the software they ran on, possibly because almost every wiki ran on its own customized software.\n\nWiki software originated from older [[version control]] systems used for documentation and software in the 1980s.  By the mid-1990s these generally had [[web browser]] interfaces.  However, they lacked the ability to easily create links between internal pages without writing [[HTML]] code.  For WikiWikiWeb, the [[CamelCase]] naming convention was used to indicate internal links, without requiring HTML code.\n\nBy the time [[MediaWiki]] appeared, this convention had been largely abandoned in favor of explicitly marking links in edited [[source code]] with double square brackets.  Page names thus did not interrupt the flow of English and could follow standard English capitalization convention.  Case-sensitivity on the first letter but not subsequent letters supported standard English capitalization conventions and let writers author their pages in ordinary English, with the linking of particular words and phrases afterward.  This proved to be the critical change that allowed ordinary authors of English to write wiki pages, and non-technical users to read them.  This policy was extended to other natural languages, avoiding the use of unusual-looking text or awkward capitalization that violates the language's own rules.\n\nOver the next 10 years, many more [[List of wiki software|wiki applications]] were written, in a variety of [[programming language]]s. After 2005, there began to be a move toward increasing consolidation and standardization: many less-popular wiki applications were gradually abandoned, and fewer new applications were created. Relatively few of the wiki engines currently in use were created after 2006.\n\nThe idea of having wiki functionality is now seen as desirable generally and some aspects of wiki functionality has also been added to existing [[content management system]]s, such as [[Microsoft SharePoint]]. Some writers have pointed out that SharePoint does not in fact function as a wiki, even with this functionality in use."}},
{"article_title": "Windows XP", "pageid": "33879", "revid": "1063145122", "timestamp": "2022-01-01T14:12:57Z", "history_paths": [["Windows XP --- Introduction ---"], ["Windows XP --- Introduction ---", "Development"], ["Windows XP --- Introduction ---", "Support lifecycle"], ["Windows XP --- Introduction ---", "Source code leak"]], "categories": ["windows xp", "2001 software", "products and services discontinued in 2014", "windows nt", "ia-32 operating systems", "obsolete technologies"], "heading_tree": {"Windows XP --- Introduction ---": {"Development": {"Release": {}}, "New and updated features": {"User interface": {}, "Infrastructure": {}, "Networking and internet functionality": {}, "Backwards compatibility": {}, "Other features": {}}, "Removed features": {}, "Editions": {}, "Service packs": {"Service Pack 1": {}, "Service Pack 2": {}, "Service Pack 3": {}}, "System requirements": {"Notes": {}, "Physical memory limits": {}, "Processor limits": {}}, "Support lifecycle": {"End of support": {}}, "Reception": {"Market share": {}}, "Source code leak": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Windows XP --- Introduction ---": "{{pp-pc1}}\n{{Short description|Personal computer operating system by Microsoft released in 2001}}\n{{Good article}}\n{{Use mdy dates|date=January 2020}}\n{{Infobox OS version\n| name = Microsoft Windows XP\n| version of = [[Windows NT]]\n| logo = Windows logo - 2002.svg\n| logo size = 64px\n| screenshot = Windows XP SP3.png\n| caption = A screenshot of Windows XP Professional with Service Pack 3 installed.\n| developer = [[Microsoft]]\n| discontinued = yes\n| first_release_date = {{Start date and age|2001|8|24}}<ref name="MS-ready-for-RTM">{{cite web |title=An Inside Look at the Months-long Process of Getting Windows XP Ready for Release to Manufacturing {{!}} Stories |url=https://news.microsoft.com/2001/08/24/an-Inside-look-at-the-months-long-process-of-getting-windows-xp-ready-for-release-to-manufacturing/ |website=Microsoft Stories |publisher=Microsoft |access-date=June 24, 2018 |date=August 24, 2001 |archive-date=August 5, 2019 |archive-url=https://web.archive.org/web/20190805122634/https://news.microsoft.com/2001/08/24/an-Inside-look-at-the-months-long-process-of-getting-windows-xp-ready-for-release-to-manufacturing/ |url-status=live }}</ref>\n| first_release_url = \n| GA_date = {{Start date and age|2001|10|25}}<ref name="MS-ready-for-RTM"/>\n| GA_url = \n| release_version = Service Pack 3 (5.1.2600.5512)\n| release_date = {{Start date and age|2008|4|21|df=no|date=August 2011}}<ref name="TRSP3date">{{cite web |first1=Gordon |last1=Kelly |title=Windows XP SP3 Release Date(s) Confirmed |url=https://www.trustedreviews.com/news/windows-xp-sp3-release-date-s-confirmed-2737589 |website=Trusted Reviews |publisher=Trusted Reviews |access-date=June 23, 2018 |archive-url=https://web.archive.org/web/20180623230020/http://www.trustedreviews.com/news/windows-xp-sp3-release-date-s-confirmed-2737589/ |archive-date=June 23, 2018 |url-status=dead |date=April 16, 2008 }}</ref>\n| source_model = {{ubl\n| [[Proprietary software|Closed-source]]\n| [[Source-available software|Source-available]] (through [[Shared Source Initiative]])<ref>{{cite web|url=https://www.microsoft.com/resources/sharedsource/windowslp.mspx|title=Windows Licensing Programs|publisher=[[Microsoft]]|access-date=September 21, 2008|url-status=live|archive-url=https://web.archive.org/web/20081216125724/http://www.microsoft.com/resources/sharedsource/windowslp.mspx|archive-date=December 16, 2008|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n}}\n| license = [[Proprietary software|Proprietary]] [[commercial software]]\n| supported_platforms = [[IA-32]], [[x86-64]], and [[Itanium]]\n| kernel_type = [[Hybrid kernel|Hybrid]] ([[Architecture of Windows NT|NT]])\n| userland = [[Windows API]], [[NTVDM]], [[Windows Services for UNIX|SFU]]\n| updatemodel = {{plainlist|\n* [[Windows Update]]\n* [[Windows Server Update Services]] (WSUS)\n* [[System Center Configuration Manager]] (SCCM)}}\n| support_status = {{Plainlist|\n* Mainstream support ended on April 14, 2009<ref name="lifecycle-db" />\n* Extended support ended on April 8, 2014<ref name="lifecycle-db" />\n* Some security updates were [[Windows_XP#End_of_support|released after this point]]\n  }}\n| preceded_by = [[Windows 2000]] (1999) <br> [[Windows Me]] (2000)\n| succeeded_by = [[Windows Vista]] (2007)\n| date = January 2009\n| website = \n}}\n{{Windows XP}}\n'''Windows XP''' is<!--Do ''not'' change to "was". This violates [[MOS:TENSE]], which specifies that all articles on operating systems are written in present tense, even if discontinued.--> a major release of the [[Windows NT]] [[operating system]] developed by [[Microsoft]]. It is the direct successor to both [[Windows 2000]] for professional users and [[Windows Me]] for home users, and was [[release to manufacturing|released to manufacturing]] on August 24, 2001, and later to retail on October 25, 2001.\n\nDevelopment of Windows XP began in the late 1990s under the codename "[[Windows Neptune|Neptune]]", built on the [[Architecture of Windows NT#Kernel|Windows NT kernel]] that was intended specifically for mainstream consumer use. An updated version of Windows 2000 was also originally planned for the business market; however, in January 2000, both projects were scrapped in favor of a single OS codenamed "Whistler", which would serve as a single platform for both consumer and business markets. As such, Windows XP is the first consumer edition of Windows not to be based on the [[Windows 95]] kernel and [[MS-DOS]].<ref name=cnettop>{{cite web | url=https://www.zdnet.com/article/top-10-things-you-must-know-about-win-xp/ | title=The 10 top things you MUST know about Win XP | publisher=[[CNET Networks]] | work=[[ZDNet]] | date=October 25, 2001 | access-date=July 22, 2008 | first=David | last=Coursey | url-status=live | archive-url=https://web.archive.org/web/20151208055856/http://www.zdnet.com/article/top-10-things-you-must-know-about-win-xp/ | archive-date=December 8, 2015 | df=mdy-all }}</ref>\n\nUpon its release, Windows XP received critical acclaim, with many noting increased performance and stability (especially in comparison to Windows Me), a more intuitive user interface, improved hardware support, and expanded multimedia capabilities. However, some industry reviewers were concerned by the new licensing model and [[Microsoft Product Activation|product activation system]].<ref>{{cite news|last=Lake|first=Matt|title=Windows XP|url=http://home.cnet.com/software/0-6688749-8-7007240-2.html|archive-url=https://web.archive.org/web/20011119231138/http://home.cnet.com/software/0-6688749-8-7007240-2.html |archive-date=November 19, 2001|access-date=May 29, 2014|newspaper=CNET Review|date=September 3, 2001}}</ref> Windows XP and [[Windows Server 2003]] were succeeded by [[Windows Vista]] and [[Windows Server 2008]], released in 2007 and 2008, respectively.\n\nMainstream support for Windows XP ended on April 14, 2009,<ref name="lifecycle-db" /> and extended support ended on April 8, 2014,<ref name="lifecycle-db" /> after which the operating system [[End-of-life (product)|ceased receiving further support or security updates]]. Windows Embedded POSReady 2009, based on Windows XP Professional, received security updates until April 2019. Unofficial methods were made available to apply the updates to other editions of Windows XP, but Microsoft discouraged this practice, citing incompatibility issues.<ref name="updates2019">{{Cite web|url=https://www.zdnet.com/article/registry-hack-enables-continued-updates-for-windows-xp/|title=Registry hack enables continued updates for Windows XP|date=2014-05-26|access-date=2021-01-30|website=ZDNet|last=Seltzer|first=Larry|quote=[UPDATE:] Late Monday we received a statement from a Microsoft spokesperson:      We recently became aware of a hack that purportedly aims to provide security updates to Windows XP customers. The security updates that could be installed are intended for Windows Embedded and Windows Server 2003 customers and do not fully protect Windows XP customers. Windows XP customers also run a significant risk of functionality issues with their machines if they install these updates, as they are not tested against Windows XP. The best way for Windows XP customers to protect their systems is to upgrade to a more modern operating system, like Windows 7 or Windows 8.1.|archive-date=January 26, 2021|archive-url=https://web.archive.org/web/20210126140239/https://www.zdnet.com/article/registry-hack-enables-continued-updates-for-windows-xp/|url-status=live}}</ref> {{As of|2021|12|df=}},<!-- If you change this "As of" month, don't forget to also update the gs.statcounter.com url below. --> 0.5% of Windows PCs<ref>{{Cite web|url=https://gs.statcounter.com/windows-version-market-share/desktop/worldwide/#monthly-201802-202111|title=Desktop Windows Version Market Share Worldwide {{!}} StatCounter Global Stats|website=gs.statcounter.com|publisher=Statcounter|language=en|access-date=December 11, 2021|archive-date=April 20, 2019|archive-url=https://web.archive.org/web/20190420180627/http://gs.statcounter.com/windows-version-market-share/desktop/worldwide#monthly-201802-202108|url-status=live}}</ref> <!--Windows desktop--> run Windows XP (on all continents the share is below 1%), and 0.18% of all devices across all platforms run Windows XP. Windows XP is still very prevalent in many countries, such as [[Armenia]], where 50\u201360% of computers use it.<ref name="Armenia"/><ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20210401-20210508|access-date=2021-12-11|website=StatCounter Global Stats|language=en}}</ref>\n{{TOC limit|limit=4}}\n\n {{Main|Development of Windows XP}}\n\nIn the late 1990s, initial development of what would become Windows XP was focused on two individual products: "[[Windows Odyssey|Odyssey]]", which was reportedly intended to succeed the future [[Windows 2000]]; and "[[Microsoft Neptune|Neptune]]", which was reportedly a consumer-oriented operating system using the [[Windows NT]] architecture, succeeding the [[MS-DOS]]-based [[Windows 98]].<ref name="cnet-consolidate">{{cite web | url=http://news.cnet.com/Microsoft-consolidates-Windows-development-efforts/2100-1040_3-236021.html | title=Microsoft consolidates Windows development efforts | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140201144705/http://news.cnet.com/Microsoft-consolidates-Windows-development-efforts/2100-1040_3-236021.html | archive-date=February 1, 2014 | df=mdy-all |date=January 24, 2000|first1=Stephanie|last1=Miles}}</ref>\n\nHowever, the projects proved to be [[Development hell|too ambitious]]. In January 2000, shortly prior to the official release of Windows 2000, technology writer Paul Thurrott reported that Microsoft had shelved both Neptune and Odyssey in favor of a new product codenamed "Whistler", named after [[Whistler, British Columbia]], as many Microsoft employees skied at the [[Whistler-Blackcomb]] ski resort.<ref name=":0">{{cite web | url=http://www.winsupersite.com/faq/longhorn.asp | title=Windows "Longhorn" FAQ | publisher=Penton Media | work=Paul Thurrott's SuperSite for Windows | date=June 22, 2005 | access-date=April 4, 2008 | url-status=dead | archive-url=https://web.archive.org/web/20080404091719/http://www.winsupersite.com/faq/longhorn.asp | archive-date=April 4, 2008 | df=mdy-all | author=<!--N/A--> }}</ref> The goal of Whistler was to unify both the consumer and business-oriented Windows lines under a single, Windows NT platform: Thurrott stated that Neptune had become "a black hole when all the features that were cut from Windows Me were simply re-tagged as Neptune features. And since Neptune and Odyssey would be based on the same code-base anyway, it made sense to combine them into a single project".<ref name="supersite-roadtoxp">{{cite web | url=http://winsupersite.com/article/product-review/the-road-to-gold-the-development-of-windows-xp-reviewed | title=The Road to Gold: The development of Windows XP Reviewed | publisher=Penton Media | work=Paul Thurrott's Supersite for Windows | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140202144509/http://winsupersite.com/article/product-review/the-road-to-gold-the-development-of-windows-xp-reviewed | archive-date=February 2, 2014 | df=mdy-all |date=October 6, 2010|first1=Paul|last1=Thurrott}}</ref>\n\nAt [[Professional Developers Conference|PDC]] on July 13, 2000, Microsoft announced that Whistler would be released during the second half of 2001, and also unveiled the first preview build, 2250, which featured an early implementation of Windows XP's visual styles system and interface changes to Windows Explorer and the Control Panel.<ref name="witpro-betabegins">{{cite web | url=https://www.itprotoday.com/windows-server/introducing-whistler-preview-build-2250 | title=Introducing the Whistler Preview, Build 2250 | publisher=Penton Media | work=Windows IT Pro | access-date=June 9, 2018 | url-status=live | archive-url=https://web.archive.org/web/20180612142613/http://www.itprotoday.com/windows-server/introducing-whistler-preview-build-2250 | archive-date=June 12, 2018 | df=mdy-all |first1=Paul|last1=Thurrott|date=July 17, 2000}}</ref>\n\nMicrosoft released the first public beta build of Whistler, build 2296, on October 31, 2000. Subsequent builds gradually introduced features that users of the release version of Windows XP would recognize, such as [[Internet Explorer 6.0]], the [[Microsoft Product Activation]] system and the ''[[Bliss (image)|Bliss]]'' desktop background.<ref name="supersite-roadtoxp2">{{cite web | url=http://winsupersite.com/article/product-review/the-road-to-gold-part-two | title=The Road to Gold (Part Two) | publisher=Penton Media | work=Paul Thurrott's SuperSite for Windows | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140202144533/http://winsupersite.com/article/product-review/the-road-to-gold-part-two | archive-date=February 2, 2014 | df=mdy-all |date=October 6, 2010|first1=Paul|last1=Thurrott}}</ref>\n\nWhistler was officially unveiled during a media event on February 5, 2001, under the name Windows XP, where XP stands for "eXPerience".<ref name="cnet-xpnamed">{{cite web | url=http://news.cnet.com/Microsoft-to-christen-Windows%2C-Office-with-new-name/2009-1001_3-252047.html | title=Microsoft to christen Windows, Office with new name | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=dead | archive-url=https://web.archive.org/web/20140201144708/http://news.cnet.com/Microsoft-to-christen-Windows%2C-Office-with-new-name/2009-1001_3-252047.html | archive-date=February 1, 2014 | df=mdy-all |date=February 5, 2001|author=<!--N/A-->}}</ref>\n\n In June 2001, Microsoft indicated that it was planning to, in conjunction with [[Intel]] and other PC makers, spend at least 1 billion US dollars on marketing and promoting Windows XP.<ref name="cnet-marketing1bn">{{cite web | url=http://news.cnet.com/2100-1001-269032.html | title=Windows XP marketing tab to hit $1 billion | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140201144711/http://news.cnet.com/2100-1001-269032.html | archive-date=February 1, 2014 | df=mdy-all |date=January 2, 2002|author=<!--N/A-->}}</ref> The theme of the campaign, "Yes You Can", was designed to emphasize the platform's overall capabilities. Microsoft had originally planned to use the slogan "Prepare to Fly", but it was replaced because of sensitivity issues in the wake of the [[September 11 attacks]].<ref name="Change-XP-slogan">{{cite web |url=https://www.computerworld.co.nz/article/511861/microsoft_changes_xp_slogan_wake_us_attacks/ |title=Microsoft changes XP slogan in wake of US attacks |work=Computerworld NZ |publisher=IDG |access-date=August 7, 2015 |url-status=live |archive-url=https://web.archive.org/web/20150905135939/http://www.computerworld.co.nz/article/511861/microsoft_changes_xp_slogan_wake_us_attacks/ |archive-date=September 5, 2015}}</ref>\n\nOn August 24, 2001, Windows XP build 2600 was [[Release to manufacturing|released to manufacturing]] (RTM). During a ceremonial media event at [[Microsoft Redmond Campus]], copies of the RTM build were given to representatives of several major PC manufacturers in [[briefcase]]s, who then flew off on decorated [[helicopter]]s. While PC manufacturers would be able to release devices running XP beginning on September 24, 2001, XP was expected to reach general, retail availability on October 25, 2001. On the same day, Microsoft also announced the final retail pricing of XP's two main editions, "Home" (as a replacement for [[Windows Me]] for home computing) and "Professional" (as a replacement for [[Windows 2000]] for high-end users).<ref name="supersite-roadtoxp3">{{cite web |url=http://winsupersite.com/article/product-review/the-road-to-gold-part-three | title=The Road to Gold (Part Three) | publisher=Penton Media | work=Paul Thurrott's Supersite for Windows | access-date=March 11, 2017| archive-url=https://web.archive.org/web/20170829035957/http://winsupersite.com/article/product-review/the-road-to-gold-part-three |archive-date=August 29, 2017 | url-status=dead|date=October 15, 2001|first1=Paul|last1=Thurrott}}</ref>\n\n {{Main|Features new to Windows XP}}\n\n [[File:Windows XP Luna.png|thumb|Screenshot of Windows XP running the [[Windows XP visual styles|Luna visual style]], showing the start menu, taskbar, and [[My Computer]] window.]]\n[[File:RoyaleXP2.PNG|thumb|Updated start menu in the Royale theme, now featuring two columns]]\n\nWhile retaining some similarities to previous versions, Windows XP's interface was overhauled with a new visual appearance, with an increased use of [[alpha compositing]] effects, [[drop shadow]]s, and "[[Windows XP visual styles|visual styles]]", which completely changed the appearance of the operating system. The number of effects enabled are determined by the operating system based on the computer's processing power, and can be enabled or disabled on a case-by-case basis. XP also added [[ClearType]], a new [[subpixel rendering]] system designed to improve the appearance of fonts on [[liquid-crystal display]]s.<ref name="Microsoft Corporation">{{cite web|url=https://support.microsoft.com/kb/306527|title=HOW TO: Use ClearType to Enhance Screen Fonts in Windows XP|publisher=[[Microsoft]]|date=October 27, 2002|work=Support|access-date=August 8, 2011|url-status=live|archive-url=https://web.archive.org/web/20110805145836/http://support.microsoft.com/kb/306527|archive-date=August 5, 2011|author=<!--N/A-->}}</ref> A new set of system icons was also introduced.<ref>{{cite web|url=https://msdn.microsoft.com/en-us/library/bb986055.aspx|title=New Graphical Interface: Enhance Your Programs with New Windows XP Shell Features|work=[[MSDN]]|publisher=[[Microsoft]]|date=November 2001|access-date=August 8, 2011|url-status=live|archive-url=https://web.archive.org/web/20110809204642/http://msdn.microsoft.com/en-us/library/bb986055.aspx|archive-date=August 9, 2011|first1=Dino|last1=Esposito}}</ref> The default wallpaper, ''[[Bliss (image)|Bliss]]'', is a photo of a landscape in the [[Napa County, California|Napa Valley]] outside [[Napa, California]], with rolling green hills and a blue sky with [[stratocumulus cloud|stratocumulus]] and [[cirrus cloud]]s.<ref name="bliss1">{{cite news |url=http://spokesmanreview.com/pf.asp?date=022204&ID=s1490284 |title=No view of Palouse from Windows |first=Paul |last=Turner |newspaper=[[The Spokesman-Review]] |location=Spokane |date=February 22, 2004 |access-date=September 19, 2012 |archive-url=https://web.archive.org/web/20110511110350/http://spokesmanreview.com/pf.asp?date=022204&ID=s1490284 |archive-date=May 11, 2011 |url-status=dead }}</ref>\n\nThe Start menu received its first major overhaul in XP, switching to a two-column layout with the ability to list, pin, and display frequently used applications, recently opened documents, and the traditional cascading "All Programs" menu. The [[taskbar]] can now group windows opened by a single application into one taskbar button, with a [[popup menu]] listing the individual windows. The notification area also hides "inactive" icons by default. A "common tasks" list was added, and [[Windows Explorer]]'s sidebar was updated to use a new task-based design with lists of common actions; the tasks displayed are contextually relevant to the type of content in a folder (e.g. a folder with music displays offers to play all the files in the folder, or burn them to a CD).<ref name="sacred">{{cite news|last1=Fitzpatrick|first1=Jason|title=The Start Menu Should Be Sacred (But It's Still a Disaster in Windows 10)|url=https://www.howtogeek.com/224805/the-start-menu-should-be-sacred-but-its-still-a-disaster-in-windows-10/|access-date=July 30, 2016|work=How-To Geek|date=August 6, 2015|archive-url=https://web.archive.org/web/20170313114850/https://www.howtogeek.com/224805/the-start-menu-should-be-sacred-but-its-still-a-disaster-in-windows-10/|archive-date=March 13, 2017|url-status=live}}</ref>\n{{Wide image|Windows XP task grouping (Luna).png|800px|The "task grouping" feature introduced in Windows XP showing both grouped and individual items}}\nFast user switching allows additional users to log into a Windows XP machine without existing users having to close their programs and logging out. Although only one user at the time can use the console (i.e. monitor, keyboard and mouse), previous users can resume their session once they regain control of the console.<ref>{{cite web|url=https://support.microsoft.com/kb/279765|title=How To Use the Fast User Switching Feature in Windows XP (Revision 1.5)|publisher=[[Microsoft]]|date=March 27, 2007|work=Microsoft Support|access-date=August 8, 2011|url-status=live|archive-url=https://web.archive.org/web/20110812020916/http://support.microsoft.com/kb/279765|archive-date=August 12, 2011|author=<!--N/A-->}}</ref>\n\n Windows XP uses [[prefetcher|prefetching]] to improve startup and application launch times.<ref name="ms-WHDC-kernel">{{cite web |url=https://www.microsoft.com/whdc/driver/kernel/XP_kernel.mspx |title=Kernel Enhancements for Windows XP |publisher=[[Microsoft]] |work=Windows Hardware Developer Center (WHDC) |date=January 13, 2003 |access-date=August 8, 2011 |url-status=live |archive-url=https://web.archive.org/web/20080307105611/http://www.microsoft.com/whdc/driver/kernel/xp_kernel.mspx |archive-date=March 7, 2008 |author=<!--N/A--> }}</ref> It also became possible to revert the installation of an updated [[device driver]], should the updated driver produce undesirable results.<ref>{{cite web|title=HOW TO: Use the Driver Roll Back Feature to Restore a Previous Version of a Device Driver in Windows XP|publisher=[[Microsoft]]|url=https://support.microsoft.com/default.aspx?kbid=306546|url-status=live|archive-url=https://web.archive.org/web/20060218123843/http://support.microsoft.com/default.aspx?kbid=306546|archive-date=February 18, 2006|date=October 27, 2002|author=<!--N/A-->}}</ref>\n\nA [[copy protection]] system known as [[Windows Product Activation]] was introduced with Windows XP and its server counterpart, [[Windows Server 2003]]. All Windows licenses must be tied to a unique ID generated using information from the [[computer hardware]], transmitted either via the internet or a telephone hotline. If Windows is not activated within 30 days of installation, the OS will cease to function until it is activated. Windows also periodically verifies the hardware to check for changes. If significant hardware changes are detected, the activation is voided, and Windows must be re-activated.<ref name="ars-activation">{{cite web|title=Windows Product Activation: an early look|url=https://arstechnica.com/microsoft/news/2001/02/wpa.ars|website=Ars Technica|access-date=February 22, 2017|url-status=live|archive-url=https://web.archive.org/web/20111205075258/http://arstechnica.com/microsoft/news/2001/02/wpa.ars|archive-date=December 5, 2011|date=February 2, 2001|first1=Ken|last1=Fisher}}</ref>{{dubious|date=April 2021}}\n\n Windows XP was originally bundled with [[Internet Explorer 6]], [[Outlook Express]] 6, [[Windows Messenger]], and [[MSN Explorer]]. New networking features were also added, including Internet Connection Firewall, [[Internet Connection Sharing]] integration with UPnP, NAT traversal APIs, Quality of Service features, IPv6 and Teredo tunneling, [[Background Intelligent Transfer Service]], extended fax features, network bridging, peer to peer networking, support for most [[Digital subscriber line|DSL]] modems, [[IEEE 802.11]] ([[Wi-Fi]]) connections with [[Wireless Zero Configuration|auto configuration]] and roaming, [[Telephony Application Programming Interface|TAPI 3.1]], and networking over FireWire.<ref>{{cite web|url=https://technet.microsoft.com/en-us/library/bb457047.aspx|title=Windows XP Networking Features and Enhancements|publisher=[[Microsoft]]|work=[[Microsoft TechNet]]|date=August 8, 2001|access-date=August 8, 2011|url-status=live|archive-url=https://web.archive.org/web/20110726172203/http://technet.microsoft.com/en-us/library/bb457047.aspx|archive-date=July 26, 2011|author=<!--N/A-->}}</ref> [[Windows Remote Assistance|Remote Assistance]] and [[Remote Desktop Services|Remote Desktop]] were also added, which allow users to connect to a computer running Windows XP from across a network or the [[Internet]] and access their applications, files, printers, and devices or request help.<ref>{{cite web|title=Frequently Asked Questions About Remote Desktop |publisher=[[Microsoft]] |url=https://www.microsoft.com/windowsxp/using/mobility/rdfaq.mspx |url-status=dead |archive-url=https://web.archive.org/web/20070704104713/http://www.microsoft.com/windowsxp/using/mobility/rdfaq.mspx |archive-date=July 4, 2007 |date=<!--N/A-->|author=<!--N/A-->}}</ref> Improvements were also made to ''IntelliMirror'' features such as [[Offline Files]], [[Roaming user profiles]] and [[Folder redirection]].<ref>{{cite web |last1=Otey |first1=Michael |title=Discover Windows XP |url=https://msdn.microsoft.com/en-us/library/ms954392.aspx |publisher=Microsoft Developer |access-date=June 21, 2018 |url-status=live |archive-url=https://web.archive.org/web/20120420161139/http://msdn.microsoft.com/en-us/library/ms954392.aspx |archive-date=April 20, 2012 |date=October 2001}}</ref>\n\n To enable running software which targets or locks out specific versions of Windows, "Compatibility mode" has been added. The feature allows pretending a selected earlier version of Windows to software, starting at Windows 95.<ref>{{cite web |title=Windows XP Program Compatibility Wizard |url=https://www.serverwatch.com/guides/windows-xp-program-compatibility-wizard/ |website=ServerWatch |access-date=13 November 2021 |date=12 March 2002}}</ref>\n\nWhile this ability was first introduced in Windows 2000 Service Pack 2, it had to be activated through the "[[regsvr32|register server]]" and was only available to administrator users, whereas Windows XP has it activated out of the box and also grants it to regular users.<ref>{{cite web |title=How to Enable Application Compatibility-Mode Technology in Windows 2000 Service Pack 2 |url=http://www.activewin.com/tips/win2000/1/2000_tips_43.shtml |website=Active Win |access-date=13 November 2021 |archive-url=https://web.archive.org/web/20010818054705/http://www.activewin.com/tips/win2000/1/2000_tips_43.shtml |archive-date=2001-08-18 |language=en |date=2000}}</ref>\n\n {{Prose|section|date=November 2021}}\n* Improved [[Compatibility layer|application compatibility]] and [[Shim (computing)|shims]] compared to Windows 2000.<ref>{{cite magazine |last=Proffit |first=Brian |date=September 2, 2002 |title=Old Apps Find A New Home On Windows XP |url=https://books.google.com/books?id=wFDKfrkjXLAC&pg=PA76 |magazine=[[PC Magazine]] |publisher=[[Ziff Davis]] |access-date=July 10, 2018 |archive-date=June 10, 2020 |archive-url=https://web.archive.org/web/20200610022353/https://books.google.com/books?id=wFDKfrkjXLAC&pg=PA76 |url-status=live }}</ref>\n* [[DirectX]] 8.1, upgradeable to DirectX 9.0c.<ref>{{cite book |last1=Karp |first1=David |last2=O'Reilly |first2=Tim |last3=Mott |first3=Troy |title=Windows XP in a Nutshell : [a desktop quick reference] |date=2005 |publisher=O'Reilly |location=Beijing [u.a.] |isbn=978-0-596-00900-7|page=[https://archive.org/details/windowsxpinnutsh00karp/page/141 141] |edition=2nd |url=https://archive.org/details/windowsxpinnutsh00karp|url-access=registration }}</ref>\n* A number of new features in [[Windows Explorer]] including task panes, thumbnails, and the option to view photos as a slideshow.<ref>{{cite web |last1=Richtmyer |first1=Richard |title=Opening up Windows XP |url=https://money.cnn.com/2001/08/23/technology/windowsxp/index.htm |website=CNN Money |publisher=CNN |access-date=June 24, 2018 |url-status=live |archive-url=https://web.archive.org/web/20171223092719/http://money.cnn.com/2001/08/23/technology/windowsxp/index.htm |archive-date=December 23, 2017 |date=August 23, 2001}}</ref>\n* Improved imaging features such as ''Windows Picture and Fax Viewer''.<ref name="WPFW">{{cite web |url         = https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/image_overview.mspx?mfr=true |title       = Windows Picture and Fax Viewer overview |work        = Windows XP Professional Product Documentation |publisher   = Microsoft Corporation |access-date  = November 23, 2010 |url-status     = live |archive-url  = https://web.archive.org/web/20101202003013/http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/image_overview.mspx?mfr=true |archive-date = December 2, 2010 |df          = dmy-all |date = <!--N/A--> |author=<!--N/A-->}}</ref>\n* Faster start-up, (because of improved [[Prefetcher|Prefetch]] functions) logon, logoff, [[Hibernate (OS feature)|hibernation]], and application launch sequences.<ref name="ms-WHDC-kernel" />\n* Numerous improvements to increase the system reliability such as improved [[System Restore]],<ref>{{cite web|archive-url=https://web.archive.org/web/20050204174622/http://msdn.microsoft.com/library/en-us/dnwxp/html/windowsxpsystemrestore.asp |archive-date=February 4, 2005|url=https://msdn.microsoft.com/library/en-us/dnwxp/html/windowsxpsystemrestore.asp |title=Microsoft Windows XP System Restore|publisher=Microsoft|last1=Harder|first1=Bobbie|date=April 2001}}</ref> [[Automated System Recovery]],<ref>{{cite web |last1=Petri |first1=Daniel |title=What is ASR in Windows XP and Windows Server 2003? |url=https://www.petri.com/whats_asr_in_windows_xp_2003 |website=Petri |publisher=Blue Whale Web Media Group |access-date=June 24, 2018 |date=January 8, 2009 |url-status=live |archive-url=https://web.archive.org/web/20170312131838/https://www.petri.com/whats_asr_in_windows_xp_2003 |archive-date=March 12, 2017 }}</ref> and driver reliability improvements through Device Driver Rollback.<ref>{{cite book |last1=Columbus |first1=Louis |title=Exploring Windows XP's Device Driver Rollback and System Restore |url=http://www.informit.com/articles/article.aspx?p=21919 |website=InformIT |publisher=Pearson Education |access-date=June 24, 2018 |date=June 29, 2001 |url-status=live |archive-url=https://web.archive.org/web/20140105185554/http://www.informit.com/articles/article.aspx?p=21919 |archive-date=January 5, 2014}}</ref>\n* Hardware support improvements such as [[FireWire]] 800,<ref>{{cite book |last1=Norton |first1=Peter |last2=Mueller |first2=John Paul |title=Peter Norton's Complete Guide to Windows XP |date=2002 |publisher=Pearson Education |isbn=9780132715386 |page=N/A |url=https://books.google.com/books?id=QLtjChi0LkMC&pg=PT339 |access-date=July 10, 2018 |archive-date=April 15, 2021 |archive-url=https://web.archive.org/web/20210415032546/https://books.google.com/books?id=QLtjChi0LkMC&pg=PT339 |url-status=live }}</ref> and improvements to [[multi-monitor]] support under the name "DualView".<ref>{{cite web |last1=McNamee |first1=Kieran |title=Setting up dual monitors using Windows XP Home |url=https://www.pcworld.idg.com.au/article/70163/setting_up_dual_monitors_using_windows_xp_home/ |website=PC World |access-date=June 24, 2018 |language=en-AU |url-status=live |archive-url=https://web.archive.org/web/20170205070537/http://www.pcworld.idg.com.au/article/70163/setting_up_dual_monitors_using_windows_xp_home |archive-date=February 5, 2017 |date=June 27, 2003 }}</ref>\n* [[Fast user switching]].<ref>{{cite web |title=Architecture of Fast User Switching |url=https://support.microsoft.com/kb/294737 |website=Microsoft Knowledgebase |publisher=Microsoft |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20090802094623/http://support.microsoft.com/kb/294737 |archive-date=August 2, 2009 |date=January 15, 2006 |url-status=dead |author=<!--N/A-->}}</ref>\n* The [[ClearType]] font rendering mechanism, which is designed to improve text readability on [[liquid-crystal display]] (LCD) and similar monitors, especially laptops.<ref name="Microsoft Corporation"/>\n* [[Side-by-side assembly|Side-by-side assemblies]]<ref>{{cite web |last1=Satran |first1=Michael |title=About Side-by-Side Assemblies |url=https://docs.microsoft.com/en-us/windows/desktop/sbscs/about-side-by-side-assemblies- |website=docs.microsoft.com |publisher=Microsoft |access-date=June 24, 2018 |language=en-us |url-status=live |archive-url=https://web.archive.org/web/20180624182601/https://docs.microsoft.com/en-us/windows/desktop/sbscs/about-side-by-side-assemblies- |archive-date=June 24, 2018 |date=May 31, 2018}}</ref> and [[RegFree COM|registration-free COM]].<ref>{{cite web |last1=Wienholt |first1=Nick |title=Simplify Application Deployment with Registration-Free COM - Developer.com |url=https://www.developer.com/net/cplus/article.php/3626016/Simplify-Application-Deployment-with-Registration-Free-COM.htm |website=www.developer.com |publisher=QuinStreet Enterprise |access-date=June 24, 2018 |url-status=live |archive-url=https://web.archive.org/web/20101216070912/http://www.developer.com/net/cplus/article.php/3626016/Simplify-Application-Deployment-with-Registration-Free-COM.htm |archive-date=December 16, 2010 |date=August 14, 2006}}</ref>\n* General improvements to international support such as more locales, languages and scripts, [[Multilingual User Interface|MUI]] support in Terminal Services, improved [[Input Method Editor]]s, and National Language Support.<ref>{{cite book |last1=Honeycutt |first1=Jerry |title=Introducing Microsoft Windows Server 2003 |date=2003 |publisher=Microsoft |location=Redmond, Wash. |isbn=9780735615700 |pages=[https://archive.org/details/introducingmicro00hone/page/293 293\u2013298] |url-access=registration |url=https://archive.org/details/introducingmicro00hone/page/293 }}</ref>\n\n {{Main|List of features removed in Windows XP}}\n\nSome of the programs and features that were part of the previous versions of Windows did not make it to Windows XP. Various [[MS-DOS]] commands available in its [[Windows 9x]] predecessor were removed,<ref>{{cite web|url=https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/dos_diffs.mspx?mfr=true |title=New ways to do familiar tasks |publisher=[[Microsoft]] |work=Windows XP Product Documentation |access-date=May 21, 2014 |url-status=live |archive-url=https://web.archive.org/web/20060503205403/http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/dos_diffs.mspx?mfr=true |archive-date=May 3, 2006 |author=<!--N/A-->|date=<!--N/A-->}}</ref> as were the [[POSIX]] and [[OS/2]] subsystems.<ref name="gg463468">{{cite web|url=https://msdn.microsoft.com/en-us/library/windows/hardware/gg463468.aspx|title=Kernel Enhancements for Windows XP|publisher=Microsoft|date=January 13, 2003|work=[[MSDN]]|access-date=April 16, 2014|archive-url=https://web.archive.org/web/20130306034824/http://msdn.microsoft.com/en-us/library/windows/hardware/gg463468.aspx|archive-date=March 6, 2013|author=<!--N/A-->}}</ref>\n\nIn [[computer networking|networking]], [[NetBEUI]], [[NWLink]] and [[NetDDE]] were [[deprecated]] and not installed by default.<ref>{{cite web |first1=Steven|last1=Pittsley |title=Easy install guide for NetBEUI and IPX in Windows XP Pro |url=https://www.techrepublic.com/article/easy-install-guide-for-netbeui-and-ipx-in-windows-xp-pro/ |website=TechRepublic |publisher=CBS Interactive |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20170411093725/https://www.techrepublic.com/article/easy-install-guide-for-netbeui-and-ipx-in-windows-xp-pro/ |archive-date=April 11, 2017|url-status=live|date=June 13, 2002}}</ref> [[Legacy Plug and Play|Plug-and-play\u2013incompatible]] communication devices (like [[modem]]s and [[network interface card]]s) were no longer supported.<ref>{{cite web|url=https://support.microsoft.com/kb/295745 |title=Non-Plug and Play Network Device Support in Windows XP |publisher=[[Microsoft]] |date=October 18, 2001 |work=Support |access-date=November 8, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20041030215121/http://support.microsoft.com/kb/295745 |archive-date=October 30, 2004 |author=<!--N/A-->}}</ref>\n\n[[#Service Pack 2|Service Pack 2]] and [[#Service Pack 3|Service Pack 3]] also removed features from Windows XP, but to a less noticeable extent. For instance, support for [[TCP half-open]] connections was removed in Service Pack 2,<ref>{{cite web|url=https://msdn.microsoft.com/en-us/library/windows/desktop/ms740548.aspx|title=TCP/IP Raw Sockets (Windows)|publisher=[[Microsoft]]|work=[[MSDN]]|access-date=November 7, 2012|archive-url=https://archive.today/20130128183317/http://msdn.microsoft.com/en-us/library/windows/desktop/ms740548.aspx|archive-date=January 28, 2013|url-status=live|author=<!--N/A-->|date=<!--N/A-->}}</ref> and the address bar on the taskbar was removed in Service Pack 3.<ref>{{cite web |last1=Pash |first1=Adam |title=Field Guide to Windows XP SP3 |url=https://lifehacker.com/385295/field-guide-to-windows-xp-sp3 |website=Lifehacker |publisher=Univision Communications |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20180115215957/https://lifehacker.com/385295/field-guide-to-windows-xp-sp3 |archive-date=January 15, 2018|url-status=live|date=April 29, 2008}}</ref>\n\n {{Main|Windows XP editions}}\n\n[[File:XP-Editions.svg|thumb|280px|Diagram representing the main editions of Windows XP. It is based on the category of the edition (grey) and codebase (black arrow).]]\n\nWindows XP was released in two major editions on launch: ''Home Edition'' and ''Professional Edition''. Both editions were made available at retail as pre-loaded software on new computers and as boxed copies. Boxed copies were sold as "Upgrade" or "Full" licenses; the "Upgrade" versions were slightly cheaper, but require an existing version of Windows to install. The "Full" version can be installed on systems without an operating system or existing version of Windows.<ref name=cnet-marketing1bn/> The two editions of XP were aimed at different markets: ''Home Edition'' is explicitly intended for consumer use and disables or removes certain advanced and enterprise-oriented features present on ''Professional'', such as the ability to join a [[Windows domain]], [[Internet Information Services]], and [[Multilingual User Interface]]. Windows 98 or Me can be upgraded to either edition, but [[Windows NT 4.0]] and Windows 2000 can only be upgraded to ''Professional''.<ref name=technet-differences>{{cite web|title=Differences with Windows XP Home Edition|url=https://technet.microsoft.com/en-us/library/bb457127.aspx|work=TechNet|publisher=[[Microsoft]]|access-date=January 26, 2014|url-status=live|archive-url=https://web.archive.org/web/20140209183913/http://technet.microsoft.com/en-us/library/bb457127.aspx|archive-date=February 9, 2014|date=September 11, 2009|author=<!--N/A-->}}</ref> Windows' [[software license agreement]] for pre-loaded licenses allows the software to be "returned" to the OEM for a refund if the user does not wish to use it.<ref>{{cite web | url=https://www.networkworld.com/news/2006/110706-dell-windows.html | title=Dell customer gets Windows refund | publisher=IDG | work=LinuxWorld | date=November 6, 2006 | access-date=September 13, 2008 | first=Don | last=Marti | url-status=dead | archive-url=https://web.archive.org/web/20080927111046/http://www.networkworld.com/news/2006/110706-dell-windows.html | archive-date=September 27, 2008 | df=mdy-all }}</ref> Despite the refusal of some manufacturers to honor the entitlement, it has been enforced by courts in some countries.<ref>{{cite web|url=http://pages.citebite.com/s2u3d5wajak|title=HP must reimburse Italian PC buyer the amount paid for Microsoft software|publisher=Heise online|date=October 29, 2007|access-date=September 13, 2008|url-status=live|archive-url=https://web.archive.org/web/20081015203020/http://pages.citebite.com/s2u3d5wajak|archive-date=October 15, 2008|author=<!--N/A-->}}</ref>\n\nTwo specialized variants of XP were introduced in 2002 for certain types of hardware, exclusively through [[original equipment manufacturer|OEM]] channels as pre-loaded software. ''[[Windows XP Media Center Edition]]'' was initially designed for high-end [[home theater PC]]s with [[TV tuner]]s (marketed under the term "Media Center PC"), offering expanded multimedia functionality, an [[electronic program guide]], and [[digital video recorder]] (DVR) support through the [[Windows Media Center]] application.<ref name="cnet-xpmceannounce">{{cite web | url=http://news.cnet.com/Microsoft-reveals-media-XP-details/2100-1016_3-944063.html | title=Microsoft reveals media XP details | publisher=CNET Networks | work=CNET | access-date=January 26, 2014 | url-status=live | archive-url=https://web.archive.org/web/20150207142141/http://news.cnet.com/Microsoft-reveals-media-XP-details/2100-1016_3-944063.html | archive-date=February 7, 2015 | df=mdy-all |first1=Joe|last1=Wilcox|date=July 16, 2002}}</ref> Microsoft also unveiled ''[[Windows XP Tablet PC Edition]]'', which contains additional [[Stylus (computing)|pen input]] features, and is optimized for mobile devices meeting its [[Microsoft Tablet PC|Tablet PC]] specifications.<ref name="cnet-tabletpcdrive">{{cite web | url=http://news.cnet.com/Microsoft-launches-tablet-PC-drive/2100-1005_3-964903.html | title=Microsoft launches tablet PC drive | publisher=CNET Networks | work=CNET | access-date=January 26, 2014 | url-status=live | archive-url=https://web.archive.org/web/20150207141635/http://news.cnet.com/Microsoft-launches-tablet-PC-drive/2100-1005_3-964903.html | archive-date=February 7, 2015 | df=mdy-all |date=November 7, 2002|first1=Joe|last1=Wilcox|first2=Sandeep|last2=Junnarkar}}</ref> Two different [[64-bit computing|64-bit]] editions of XP were made available. The first, ''Windows XP 64-Bit Edition'', was intended for [[IA-64]] ([[Itanium]]) systems; as IA-64 usage declined on workstations in favor of [[AMD]]'s [[x86-64]] architecture, the Itanium edition was discontinued in January 2005.<ref name=computerworld-xpitaniumdiscontinued>{{cite web|title=Microsoft nixes Windows XP for Itanium|url=https://www.computerworld.com/s/article/98716/Microsoft_nixes_Windows_XP_for_Itanium?taxonomyId=125|work=Computerworld|publisher=[[International Data Group|IDG]]|access-date=January 26, 2014|url-status=live|archive-url=https://web.archive.org/web/20140202171023/http://www.computerworld.com/s/article/98716/Microsoft_nixes_Windows_XP_for_Itanium?taxonomyId=125|archive-date=February 2, 2014|date=January 5, 2005|first1=Joris|last1=Evers}}</ref> A new 64-bit edition supporting the x86-64 architecture, called ''Windows XP Professional x64 Edition'', was released in April of the same year.<ref name="release-date-x64">{{cite press release |url=http://news.microsoft.com/2005/04/25/microsoft-raises-the-speed-limit-with-the-availability-of-64-bit-editions-of-windows-server-2003-and-windows-xp-professional/ |title=Microsoft Raises the Speed Limit with the Availability of 64-Bit Editions of Windows Server 2003 and Windows XP Professional |publisher=[[Microsoft]] |date=April 25, 2005 |access-date=September 10, 2015 |archive-date=February 25, 2015 |archive-url=https://web.archive.org/web/20150225210214/http://news.microsoft.com/2005/04/25/microsoft-raises-the-speed-limit-with-the-availability-of-64-bit-editions-of-windows-server-2003-and-windows-xp-professional/ |url-status=live }}</ref>\n\nMicrosoft also targeted [[emerging market]]s with the 2004 introduction of ''[[Windows XP Starter Edition]]'', a special variant of ''Home Edition'' intended for low-cost PCs. The OS is primarily aimed at first-time computer owners, containing heavy [[Software localization|localization]] (including wallpapers and screen savers incorporating images of local landmarks), and a "My Support" area which contains video tutorials on basic computing tasks. It also removes certain "complex" features, and does not allow users to run more than three applications at a time. After a pilot program in [[India]] and [[Thailand]], ''Starter'' was released in other emerging markets throughout 2005.<ref>{{cite web|url=http://winsupersite.com/windows-xp/windows-xp-starter-edition|title=Windows XP Starter Edition|first=Paul|last=Thurrott|date=January 3, 2005|access-date=April 12, 2008|work=Paul Thurrott's SuperSite for Windows|publisher=[[Penton Media]]|url-status=dead|archive-url=https://web.archive.org/web/20130828180310/http://winsupersite.com/windows-xp/windows-xp-starter-edition|archive-date=August 28, 2013}}</ref> In 2006, Microsoft also unveiled the [[Microsoft FlexGo|FlexGo]] initiative, which would also target emerging markets with [[Subsidy|subsidized]] PCs on a pre-paid, subscription basis.<ref name=cnet-payasyougo>{{cite web|title=Microsoft pitches pay-as-you-go PCs|url=http://news.cnet.com/Microsoft-pitches-pay-as-you-go-PCs/2100-1003_3-6074589.html|work=CNET|publisher=CNET Networks|access-date=January 26, 2014|url-status=live|archive-url=https://web.archive.org/web/20150207143018/http://news.cnet.com/Microsoft-pitches-pay-as-you-go-PCs/2100-1003_3-6074589.html|archive-date=February 7, 2015|date=May 23, 2006|first1=Ina|last1=Fried}}</ref>\n\nAs a result of [[unfair competition]] lawsuits in [[Europe]] and [[South Korea]], which both alleged that Microsoft had improperly leveraged its status in the PC market to favor its own bundled software, Microsoft was ordered to release special editions of XP in these markets that excluded certain applications. In March 2004, after the [[European Commission]] [[European Union Microsoft competition case|fined]] Microsoft \u20ac497 million (US$603 million), Microsoft was ordered to release "N" editions of XP that excluded Windows Media Player, encouraging users to pick and download their own [[Media player (application software)|media player]] software.<ref name="WinXPSBBC">{{cite news|url=https://news.bbc.co.uk/2/hi/business/4388349.stm|publisher=BBC|title=Microsoft and EU reach agreement|date=March 28, 2005|url-status=live|archive-url=https://web.archive.org/web/20150922061907/http://news.bbc.co.uk/2/hi/business/4388349.stm|archive-date=September 22, 2015|author=<!--N/A-->}}</ref> As it was sold at the same price as the edition with Windows Media Player included, certain OEMs (such as [[Dell]], who offered it for a short period, along with [[Hewlett-Packard]], [[Lenovo]] and [[Fujitsu Siemens Computers|Fujitsu Siemens]]) chose not to offer it. Consumer interest was minuscule, with roughly 1,500 units shipped to [[Original Equipment Manufacturer|OEMs]], and no reported sales to consumers.<ref name="WinXPSSeattlePi">{{cite news | url=https://www.seattlepi.com/business/205093_msftfolo24.html <!-- 451 Unavailable For Legal Reasons --> | title=Europe gets 'reduced' Windows | publisher=[[Hearst Corporation]] | work=Seattle Post-Intelligencer | date=December 24, 2004 | first1=Todd | last1=Bishop | access-date=November 30, 2018 | archive-date=October 6, 2021 | archive-url=https://web.archive.org/web/20211006095524/https://www.seattlepi.com/business/article/Europe-gets-reduced-Windows-1162710.php | url-status=live }}</ref> In December 2005, the [[Fair Trade Commission (South Korea)|Korean Fair Trade Commission]] ordered Microsoft to make available editions of Windows XP and Windows Server 2003 that do not contain Windows Media Player or Windows Messenger.<ref>{{cite web | url=https://arstechnica.com/news.ars/post/20051207-5702.html | title=South Korea fines Microsoft for antitrust abuses | publisher=Cond\u00e9 Nast Publications | work=Ars Technica | date=December 7, 2005 | access-date=April 12, 2008 | first=Nate | last=Anderson | url-status=live | archive-url=https://web.archive.org/web/20080422014515/http://arstechnica.com/news.ars/post/20051207-5702.html | archive-date=April 22, 2008 | df=mdy-all }}</ref> The "K" and "KN" editions of Windows XP were released in August 2006, and are only available in English and Korean, and also contain links to third-party [[instant messenger]] and media player software.<ref>{{cite web |url         = http://support.microsoft.com/kb/922474 |title       = Changes to Windows XP Home Edition K and Windows XP Professional K from earlier versions of Windows XP (MSKB 922474) |date        = September 15, 2006 |access-date  = January 26, 2014 |work        = Microsoft Support |publisher   = Microsoft |url-status     = live |archive-url  = https://web.archive.org/web/20131219020559/http://support.microsoft.com/kb/922474 |archive-date = December 19, 2013 |df          = mdy-all |author = <!-- N/A -->}}</ref>\n\n A [[service pack]] is a cumulative update package that is a superset of all updates, and even service packs, that have been released before it.<ref>{{Cite web|url=https://support.microsoft.com/en-us/help/14162/windows-service-pack-and-update-center|title=Service Pack and Update Center|date=September 10, 2016|website=Support|publisher=[[Microsoft]]|url-status=live|archive-url=https://web.archive.org/web/20170831045620/https://support.microsoft.com/en-us/help/14162/windows-service-pack-and-update-center|archive-date=August 31, 2017|author=<!--N/A-->}}</ref> Three service packs have been released for Windows XP. Service Pack 3 is slightly different, in that it needs at least Service Pack 1 to have been installed, in order to update a live OS.<ref>{{Cite web|url=https://technet.microsoft.com/en-us/library/cc507836.aspx|title=Installing Windows XP Service Pack 3 (SP3)|date=November 18, 2011|website=[[Microsoft TechNet|Microsoft]]|publisher=[[Microsoft]]|access-date=August 22, 2017|url-status=live|archive-url=https://web.archive.org/web/20170822181613/https://technet.microsoft.com/en-us/library/cc507836.aspx|archive-date=August 22, 2017|author=<!--N/A-->}}</ref> However, Service Pack 3 can still be [[Slipstream (computing)|embedded into a Windows installation disc]]; SP1 is not reported as a prerequisite for doing so.<ref>{{Cite news|url=http://lifehacker.com/386526/slipstream-service-pack-3-into-your-windows-xp-installation-cd|title=Slipstream Service Pack 3 into Your Windows XP Installation CD|last=Purdy|first=Kevin|work=Lifehacker|access-date=August 22, 2017|url-status=live|archive-url=https://web.archive.org/web/20170822180903/http://lifehacker.com/386526/slipstream-service-pack-3-into-your-windows-xp-installation-cd|archive-date=August 22, 2017}}</ref>\n\n Service Pack 1 (SP1) for Windows XP was released on September 9, 2002. It contained over 300 minor, post-RTM bug fixes, along with all security patches released since the original release of XP. SP1 also added USB 2.0 support, the [[Microsoft Java Virtual Machine]], [[.NET Framework]] support, and support for technologies used by the then-upcoming ''Media Center'' and ''Tablet PC'' editions of XP.<ref name=pcmag-xpsp1>{{cite web|title=Windows XP SP1 Irons out the Wrinkles|url=https://www.pcmag.com/article2/0,2817,526004,00.asp|work=PC Magazine|access-date=January 26, 2014|url-status=live|archive-url=https://web.archive.org/web/20140226221844/http://www.pcmag.com/article2/0,2817,526004,00.asp|archive-date=February 26, 2014}}</ref> The most significant change on SP1 was the addition of ''Set Program Access and Defaults'', a settings page which allows programs to be set as default for certain types of activities (such as media players or web browsers) and for access to bundled, Microsoft programs (such as Internet Explorer or Windows Media Player) to be disabled. This feature was added to comply with the settlement of ''[[United States v. Microsoft Corp. (2001)|United States v. Microsoft Corp.]]'', which required Microsoft to offer the ability for OEMs to bundle third-party competitors to software it bundles with Windows (such as [[Internet Explorer]] and [[Windows Media Player]]), and give them the same level of prominence as those normally bundled with the OS.<ref name="cnet-xpsp1">{{cite web | url=http://reviews.cnet.com/windows/microsoft-windows-xp-service/4505-3672_7-20039834.html | title=Microsoft Windows XP Service Pack 1 review | publisher=CNET Networks | work=CNET | access-date=January 26, 2014 | url-status=live | archive-url=https://web.archive.org/web/20080209135918/http://reviews.cnet.com/windows/microsoft-windows-xp-service/4505-3672_7-20039834.html | archive-date=February 9, 2008 | df=mdy-all|date=<!--N/A-->|first1=Edward|last1=Mendelson |author-link1=Edward Mendelson}}</ref>\n\nOn February 3, 2003, Microsoft released Service Pack 1a (SP1a). It was the same as SP1, except, the Microsoft Java Virtual Machine was excluded.<ref>{{cite web|url=https://support.microsoft.com/?kbid=813926|access-date=September 21, 2007|title=Differences Between Windows XP SP1 and Windows XP SP1a|date=February 3, 2003|url-status=live|archive-url=https://web.archive.org/web/20070127143544/http://support.microsoft.com/?kbid=813926|archive-date=January 27, 2007|author=<!--N/A-->}}</ref>\n\n [[File:Windows XP SP2 French CD.jpg|thumb|French SP2 installation disc]]\n[[File:Windows Security Center XP SP2.png|thumb|right|[[Windows Security Center]] window running Windows XP Service Pack 2, showing no virus protection installed ]]\n\nService Pack 2 (SP2) was released on August 25, 2004.<ref>{{cite web|url=https://support.microsoft.com/kb/322389|access-date=September 21, 2007|title=How to obtain the latest Windows XP service pack|archive-url=https://web.archive.org/web/20041014021822/http://support.microsoft.com/kb/322389 |archive-date=October 14, 2004 |date=March 26, 2007|author=<!--N/A-->}}</ref> Headline features included [[Wi-Fi Protected Access|WPA]] encryption compatibility for Wi-Fi and usability improvements to the Wi-Fi networking user interface,<ref>{{cite web |last1=Shinder |first1=Deb |title=Windows XP Service Pack 2: How it affects wireless networking |url=https://www.techrepublic.com/article/windows-xp-service-pack-2-how-it-affects-wireless-networking/ |website=TechRepublic |publisher=CBS Interactive |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20170613224317/https://www.techrepublic.com/article/windows-xp-service-pack-2-how-it-affects-wireless-networking/ |archive-date=June 13, 2017 |date=August 26, 2004 |url-status=dead  }}</ref> partial [[Bluetooth stack#Microsoft Windows stack|Bluetooth]] support,<ref name="WinBT 2010 FAQ">{{cite web|url=https://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/Bth_FAQ.docx|title=Bluetooth Wireless Technology FAQ \u2013 2010|date=July 24, 2012|access-date=November 4, 2012|archive-url=https://web.archive.org/web/20160303211522/http://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/Bth_FAQ.docx|archive-date=March 3, 2016|url-status=live|author=<!--N/A-->}}</ref> and various improvements to security systems.\n\nThe security improvements (codenamed "Springboard",<ref>{{cite journal|url=http://www.itprotoday.com/windows-8/windows-xp-sp2-be-springboard-longhorn|title=Windows XP SP2 to be 'Springboard' to Longhorn|journal=[[Windows IT Pro]]|first1=Paul |last1=Thurrott|date=October 15, 2003|archive-url=https://web.archive.org/web/20180623230427/http://www.itprotoday.com/windows-8/windows-xp-sp2-be-springboard-longhorn|archive-date=June 23, 2018|url-status=live}}</ref> as these features were intended to underpin additional changes in [[Windows Longhorn|Longhorn]]) included a major revision to the included firewall (renamed Windows Firewall, and now enabled by default), and an update to [[Data Execution Prevention]], which gained hardware support in the [[NX bit]] that can stop some forms of buffer overflow attacks. [[Raw socket]] support is removed (which supposedly limits the damage done by [[Zombie computer|zombie machines]]) and the [[Windows Messenger service]] (which had been abused to cause pop-up advertisements to be displayed as system messages without a web browser or any additional software) became disabled by default. Additionally, security-related improvements were made to e-mail and web browsing. Service Pack 2 also added [[Security Center]], an interface which provides a general overview of the system's security status, including the state of the firewall and automatic updates. Third-party firewall and [[antivirus software]] can also be monitored from Security Center.<ref>{{cite web|url=https://www.microsoft.com/windowsxp/sp2/overview.mspx|publisher=[[Microsoft]]|title=Windows XP Service Pack 2 information|date=August 4, 2004|url-status=live|archive-url=https://web.archive.org/web/20071016045833/http://www.microsoft.com/windowsxp/sp2/overview.mspx|archive-date=October 16, 2007|author=<!--N/A-->}}</ref>\n\nThe unique boot screens that identified the edition of Windows XP currently running, including a green progress bar for Home Edition and a blue progress bar for other editions, were removed and replaced with a generic "Windows XP" boot screen with a blue progress bar with this service pack.\n\nIn August 2006, Microsoft released updated installation media for Windows XP and Windows Server 2003 SP2 (SP2b), in order to incorporate a patch requiring [[ActiveX]] controls in Internet Explorer to be manually activated before a user may interact with them. This was done so that the browser would not violate a [[patent]] owned by [[Eolas]].<ref>{{cite web|url=https://blogs.technet.com/backroom/archive/2006/08/21/448330.aspx|publisher=[[Microsoft]]|title=Why Windows XP SP2b and Windows Server 2003 SP2a?|date=August 21, 2006|url-status=live|archive-url=https://web.archive.org/web/20090812134958/http://blogs.technet.com/backroom/archive/2006/08/21/448330.aspx|archive-date=August 12, 2009|first1=Victor|last1=Mux}}</ref> Microsoft has since licensed the patent, and released a patch reverting the change in April 2008.<ref name="msdnblog">{{cite web |title=IE Automatic Component Activation Now Available |work=IEBlog |publisher=[[Microsoft]] |date=April 8, 2008 |url=https://blogs.msdn.com/ie/archive/2008/04/08/ie-automatic-component-activation-now-available.aspx |access-date=April 11, 2008 |url-status=live |archive-url=https://web.archive.org/web/20080411232949/http://blogs.msdn.com/ie/archive/2008/04/08/ie-automatic-component-activation-now-available.aspx |archive-date=April 11, 2008 |first1=Jefferson|last1=Fletcher}}</ref> In September 2007, another minor revision known as SP2c was released for XP Professional, extending the number of available [[product key]]s for the operating system to "support the continued availability of Windows XP Professional through the scheduled system builder channel end-of-life (EOL) date of January 31, 2009."<ref name=msdn-sp2c>{{cite web|title=Microsoft Windows XP Professional Service Pack 2c Release|url=https://blogs.technet.com/b/backroom/archive/2007/08/09/microsoft-windows-xp-professional-service-pack-2c-release.aspx|work=MSDN|publisher=[[Microsoft]]|access-date=January 26, 2014|url-status=live|archive-url=https://web.archive.org/web/20140202094121/http://blogs.technet.com/b/backroom/archive/2007/08/09/microsoft-windows-xp-professional-service-pack-2c-release.aspx|archive-date=February 2, 2014|date=August 9, 2007|first1=Victor|last1=Mux}}</ref>\n\n The third and final Service Pack, SP3, was released to manufacturing on April 21, 2008,<ref name="TRSP3date"/> and to the public via both the Microsoft Download Center and [[Windows Update]] on May 6, 2008.{{Citation needed|date=October 2021}} Service Pack 3 is not available for Windows XP x64 Edition, which is based on the Windows Server 2003 kernel and, as a result, uses [[Windows Server 2003#Updates|its service packs]]<ref>{{Cite web | url=https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2003/cc773361(v=ws.10) | title=Release Notes for Microsoft Windows Server 2003 Service Pack 2 | access-date=November 11, 2019 | archive-date=November 11, 2019 | archive-url=https://web.archive.org/web/20191111110411/https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2003/cc773361(v%3Dws.10) | url-status=live }}</ref> rather than the ones for the other editions.<ref>{{cite web |last1=Oiaga |first1=Marius |title=64-Bit Windows XP Service Pack 3? |url=https://news.softpedia.com/news/64-Bit-Windows-XP-Service-Pack-3-73982.shtml |website=Softpedia |publisher=SoftNews NET |access-date=June 24, 2018 |language=en-us |url-status=live |archive-url=https://web.archive.org/web/20180508180044/https://news.softpedia.com/news/64-Bit-Windows-XP-Service-Pack-3-73982.shtml |archive-date=May 8, 2018 |date=December 14, 2007}}</ref>\n\nIt began being automatically pushed out to ''Automatic Updates'' users on July 10, 2008.<ref>{{cite web | url=https://computerworld.com/action/article.do?command=viewArticleBasic&articleId=9107918 | title=Microsoft sets XP SP3 automatic download for Thursday | publisher=IDG | work=Computerworld | date=July 8, 2008 | access-date=July 8, 2008 | url-status=dead | archive-url=https://web.archive.org/web/20080709220104/http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9107918 | archive-date=July 9, 2008 | df=mdy-all |first1=Gregg|last1=Keizer}}</ref> A feature set overview which details new features available separately as stand-alone updates to Windows XP, as well as [[backporting|backported]] features from Windows Vista, has been posted by Microsoft.<ref>{{cite web|title=Windows XP Service Pack 3 Overview |publisher=[[Microsoft]] |date=May 6, 2008 |url=https://www.microsoft.com/downloads/details.aspx?FamilyID=68c48dad-bc34-40be-8d85-6bb4f56f5110&DisplayLang=en |access-date=May 7, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080506093528/http://www.microsoft.com/downloads/details.aspx?FamilyID=68c48dad-bc34-40be-8d85-6bb4f56f5110&DisplayLang=en |archive-date=May 6, 2008 |author=<!--N/A-->}}</ref> A total of 1,174 fixes are included in SP3.<ref>{{cite web|url=https://support.microsoft.com/kb/946480|title=List of fixes that are included in Windows XP Service Pack 3|publisher=Microsoft|access-date=June 23, 2018|date=May 6, 2008|archive-url=https://web.archive.org/web/20080509105822/http://support.microsoft.com/kb/946480 |archive-date=May 9, 2008 |author=<!--N/A-->}}</ref> Service Pack 3 can be installed on systems with Internet Explorer versions 6, 7, or 8; Internet Explorer 7 is not included as part of SP3.<ref>{{cite web|url=https://news.softpedia.com/news/No-Internet-Explorer-7-Will-Not-Be-a-Part-of-Windows-XP-SP3-73896.shtml|title=No, Internet Explorer 7 Will Not(!) Be a Part of Windows XP SP3|first=Marius|last=Oiaga|publisher=SoftNews NET|url-status=live|archive-url=https://web.archive.org/web/20120118180234/http://news.softpedia.com/news/No-Internet-Explorer-7-Will-Not-Be-a-Part-of-Windows-XP-SP3-73896.shtml|archive-date=January 18, 2012|date=December 14, 2007}}</ref>\n\nService Pack 3 included security enhancements over and above those of SP2, including APIs allowing developers to enable [[Data Execution Prevention]] for their code, independent of system-wide compatibility enforcement settings,<ref>{{cite news|url=https://blogs.msdn.com/b/michael_howard/archive/2008/01/29/new-nx-apis-added-to-windows-vista-sp1-windows-xp-sp3-and-windows-server-2008.aspx|title=New NX APIs added to Windows Vista SP1, Windows XP SP3 and Windows Server 2008|work=Michael Howard's Web Log|publisher=[[Microsoft]]|date=January 29, 2008|access-date=August 8, 2011|url-status=live|archive-url=https://web.archive.org/web/20110825070102/http://blogs.msdn.com/b/michael_howard/archive/2008/01/29/new-nx-apis-added-to-windows-vista-sp1-windows-xp-sp3-and-windows-server-2008.aspx|archive-date=August 25, 2011|first1=Michael|last1=Howard}}</ref> the [[Security Support Provider Interface]],<ref>{{cite web|url=https://support.microsoft.com/kb/951608|title=Description of the Credential Security Support Provider (CredSSP) in Windows XP Service Pack 3|access-date=June 23, 2018|archive-url=https://web.archive.org/web/20091009060022/http://support.microsoft.com/kb/951608 |archive-date=October 9, 2009|publisher=Microsoft |date=May 6, 2008|author=<!--N/A-->}}</ref> improvements to [[WPA2]] security,<ref>{{cite web |date=May 13, 2005|author1=Enterprise IT Planet Staff |title=Upgraded Wi-Fi Security for Windows XP SP2 |url=http://www.wi-fiplanet.com/news/article.php/3504881/Upgraded-Wi-Fi-Security-for-Windows-XP-SP2.htm |website=Wi-Fi Planet |publisher=QuinStreet Enterprise |access-date=June 23, 2018 |archive-url=https://web.archive.org/web/20180623232221/http://www.wi-fiplanet.com/news/article.php/3504881/Upgraded-Wi-Fi-Security-for-Windows-XP-SP2.htm |archive-date=June 23, 2018 |url-status=dead  }}</ref> and an updated version of the Microsoft Enhanced Cryptographic Provider Module that is [[FIPS 140-2]] certified.<ref name="SP3Overview">{{cite web|url=https://download.microsoft.com/download/6/8/7/687484ed-8174-496d-8db9-f02b40c12982/Overview%20of%20Windows%20XP%20Service%20Pack%203.pdf|title=Overview of Windows XP Service Pack 3|url-status=live|archive-url=https://web.archive.org/web/20090117080827/http://download.microsoft.com/download/6/8/7/687484ed-8174-496d-8db9-f02b40c12982/Overview%20of%20Windows%20XP%20Service%20Pack%203.pdf|archive-date=January 17, 2009|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n\nIn incorporating all previously released updates not included in SP2, Service Pack 3 included many other key features. [[Windows Imaging Component]] allowed camera vendors to integrate their own proprietary image codecs with the operating system's features, such as thumbnails and slideshows.<ref>{{cite web|url=https://support.microsoft.com/kb/947898/en-us|title=Information about Windows Imaging Component|archive-url=https://web.archive.org/web/20110510013416/http://support.microsoft.com/kb/947898/en-us |archive-date=May 10, 2011 |publisher=Microsoft|date=August 13, 2002|author=<!--N/A-->}}</ref> In enterprise features, [[Remote Desktop Protocol]] 6.1 included support for ClearType and 32-bit color depth over RDP,<ref>{{cite web |url=https://codeyarns.com/2010/01/27/windows-cleartype-on-rdp/ |title=Windows: ClearType on RDP |publisher=CodeYarns.com |date=January 27, 2010 |access-date=June 16, 2014 |url-status=live |archive-url=https://web.archive.org/web/20151117030912/http://codeyarns.com/2010/01/27/windows-cleartype-on-rdp/ |archive-date=November 17, 2015 |first1=Ashwin|last1=Nanjappa}}</ref> while improvements made to [[Windows Management Instrumentation]] in Windows Vista to reduce the possibility of corruption of the WMI repository were [[backport]]ed to XP SP3.<ref>{{cite web|url=https://support.microsoft.com/kb/933062|title=A hotfix is available that improves the stability of the Windows Management Instrumentation repository in Windows XP|work=Support|publisher=[[Microsoft]]|date=October 8, 2011|access-date=January 20, 2013|url-status=live|archive-url=https://web.archive.org/web/20130305004704/http://support.microsoft.com/kb/933062|archive-date=March 5, 2013|author=<!--N/A-->}}</ref>\n\nIn addition, SP3 contains updates to the operating system components of Windows XP Media Center Edition (MCE) and Windows XP Tablet PC Edition, and security updates for .NET Framework version 1.0, which is included in these editions. However, it does not include update rollups for the Windows Media Center application in Windows XP MCE 2005.<ref name="SP3FAQ">{{cite web|url=https://social.technet.microsoft.com/forums/en-US/itproxpsp/thread/e6a8fb92-526e-4686-930b-2af2d9180e22/|title=FAQs regarding SP3 RTM|archive-url=https://web.archive.org/web/20110824120828/http://social.technet.microsoft.com/forums/en-US/itproxpsp/thread/e6a8fb92-526e-4686-930b-2af2d9180e22/ |archive-date=August 24, 2011 |publisher=Microsoft|access-date=June 23, 2018|date=April 22, 2008|author=<!--N/A-->}}</ref> SP3 also omits security updates for Windows Media Player 10, although the player is included in Windows XP MCE 2005.<ref name="SP3FAQ" /> <!-- PLEASE DON'T ADD WMP 11 HERE SINCE IT IS ''not'' INCLUDED IN ANY WINDOWS XP SKU. WMP 10 IS --> The Address Bar DeskBand on the Taskbar is no longer included because of antitrust violation concerns.<ref name=tr-sp3address>{{cite web|title=How do I... Return the Address bar Windows XP SP3 removed?|url=https://www.techrepublic.com/blog/windows-and-office/how-do-i-return-the-address-bar-windows-xp-sp3-removed/|website=TechRepublic|publisher=CBS Interactive|access-date=May 5, 2015|url-status=live|archive-url=https://web.archive.org/web/20150905192952/http://www.techrepublic.com/blog/windows-and-office/how-do-i-return-the-address-bar-windows-xp-sp3-removed/|archive-date=September 5, 2015|date=May 8, 2008|first1=Mark|last1=Kaelin}}</ref>\n\nUnofficial SP3 ZIP download packages were released on a now-defunct website called The Hotfix from 2005 to 2007.<ref>{{cite web | url=https://www.pcworld.idg.com.au/article/140833/ | title=Windows XP SP3 preview surfaces on Web | publisher=IDG | work=[[PC World]] | date=October 6, 2005 | access-date=October 29, 2020 | archive-date=October 31, 2020 | archive-url=https://web.archive.org/web/20201031131504/https://www.pcworld.idg.com.au/article/140833/ | url-status=live }}</ref><ref>{{cite web | url=https://arstechnica.com/uncategorized/2005/10/5399-2/ | title=Sneak preview of Windows XP SP3 surfaces | publisher=[[Ars Technica]] | work=[[Ars Technica]] | date=October 6, 2005 | access-date=October 29, 2020 | archive-date=November 4, 2020 | archive-url=https://web.archive.org/web/20201104014413/https://arstechnica.com/uncategorized/2005/10/5399-2/ | url-status=live }}</ref> The owner of the website, Ethan C. Allen, was a former Microsoft employee in Software Quality Assurance and would comb through the [[Microsoft Knowledge Base]] articles daily and download new [[hotfix]]es Microsoft would put online within the articles. The articles would have a "kbwinxppresp3fix" and/or "kbwinxpsp3fix" tag, thus allowing Allen to easily find and determine which fixes were planned for the official SP3 release to come. Microsoft publicly stated at the time that the SP3 pack was unofficial and users should not install it.<ref>{{cite web | url=https://www.pcworld.idg.com.au/article/139412/ | title=Microsoft employee blasts 'fake' service pack | publisher=IDG | work=[[PC World]] | date=October 14, 2005 | access-date=October 29, 2020 | archive-date=October 31, 2020 | archive-url=https://web.archive.org/web/20201031144052/https://www.pcworld.idg.com.au/article/139412/ | url-status=live }}</ref><ref>{{cite news | url=https://arstechnica.com/uncategorized/2005/10/5438-2/ | title=Windows XP SP3 preview a fake | publisher=[[Ars Technica]] | work=[[Ars Technica]] | date=October 15, 2005 | access-date=October 29, 2020 | archive-date=October 31, 2020 | archive-url=https://web.archive.org/web/20201031235144/https://arstechnica.com/uncategorized/2005/10/5438-2/ | url-status=live }}</ref> Allen also released a Vista SP1 package in 2007, for which Allen received a cease-and-desist email from Microsoft.<ref>{{cite web | url=https://www.pcworld.co.nz/article/180853/microsoft_leans_vista_sp1_site/%3Cspan%20class= | title=Microsoft leans on Vista SP1 site | publisher=IDG | work=[[PC World]] | date=October 4, 2007 | access-date=October 29, 2020 | archive-date=November 3, 2020 | archive-url=https://web.archive.org/web/20201103202333/https://www.pcworld.co.nz/article/180853/microsoft_leans_vista_sp1_site/%3Cspan%20class= | url-status=live }}</ref>\n\n System requirements for Windows XP are as follows:\n\n{{System requirements\n| caption = System requirements\n| useminandrec = yes\n| collapse = \n| align = none\n| width = 100%\n| pad = <!-- Default is 1em -->\n| font-size = Normal\n<!--\nMandatory section\n-->| platform1 = Home/Professional Edition{{efn-ua|1={{cite web|url=https://support.microsoft.com/kb/314865|access-date=March 12, 2007|title=System requirements for Windows XP operating systems|date=April 28, 2005|url-status=live|archive-url=https://web.archive.org/web/20110806133141/http://support.microsoft.com/kb/314865|archive-date=August 6, 2011|author=<!--N/A-->}} }}\n| os1 = \n| os1rec = \n| cpu1 = {{unbulleted list|[[Pentium]] or compatible, 233 [[MHz]]{{efn-ua|name=ref1|1=Even though this is Microsoft's stated minimum processor speed for Windows XP, it is possible to install and run the operating system on early [[IA-32]] processors such as a [[P5 (microarchitecture)|P5]] [[Pentium (brand)|Pentium]] without [[MMX (instruction set)|MMX]] instructions. Windows XP is not compatible with processors older than Pentium (such as 486) or the [[Cyrix 6x86]] because it requires {{code|CMPXCHG8B}} (see [[Pentium F00F bug]]) instructions.}}{{efn-ua|1={{cite web|title=Windows XP Minimal Requirement Test|publisher=Winhistory.de|date=September 9, 2011|url=http://winhistory.de/more/386/xpmini.htm.en|access-date=January 1, 2012|url-status=live|archive-url=https://web.archive.org/web/20111221022344/http://www.winhistory.de/more/386/xpmini.htm.en|archive-date=December 21, 2011|author=<!--N/A-->}}}}|[[BIOS]] or compatible firmware{{efn-ua|name=No_GPT_or_UEFI|1={{cite web |url=https://support.microsoft.com/kb/2581408 |title=Windows XP: Required firmware and partition mapping scheme of hard disk drive |publisher=Support.microsoft.com |date=June 26, 2013 |access-date=June 16, 2014 |url-status=live |archive-url=https://web.archive.org/web/20170427084734/https://support.microsoft.com/en-us/help/2581408/windows-support-for-hard-disks-that-are-larger-than-2-tb |archive-date=April 27, 2017 |author=<!--N/A-->}}}}}}\n| cpu1rec = {{unbulleted list|[[Pentium]] or compatible, 300 MHz|[[BIOS]] or compatible firmware{{efn-ua|name=No_GPT_or_UEFI}}}}\n| memory1 = 64 [[Megabyte|MB]]{{efn-ua|name=ref2|1=A Microsoft TechNet paper from Summer 2001 (before Windows XP's actual release), states that: "A computer with 64 MB of RAM will have sufficient resources to run Windows XP and '''a few''' applications with moderate memory requirements." (Emphasis added.) These were said to be office productivity applications, e-mail programs, and web browsers (of the time). With such a configuration, user interface enhancements and fast user switching are turned off by default. For comparable workloads, 64 MB of RAM was then regarded as providing an equal or better user experience on Windows XP with similar settings than it would with [[Windows Me]] on the same hardware. In a later section of the paper, superior performance over Windows Me was noted with 128 MB of RAM or more, and with computers that exceed the minimum hardware requirements.}}{{efn-ua|1={{cite journal|last1=Sechrest|first1=Stuart|last2=Fortin|first2=Michael|journal=[[Microsoft TechNet]]|url=https://technet.microsoft.com/en-us/library/bb457057.aspx|access-date=April 8, 2008|title=Windows XP Performance|date=June 1, 2001|url-status=live|archive-url=https://web.archive.org/web/20100727133954/http://technet.microsoft.com/en-us/library/bb457057.aspx|archive-date=July 27, 2010}}}}\n| memory1rec = 128 MB\n| gpu1 = \n| gpu1rec = \n| sound1 = N/A\n| sound1rec = [[Sound card]] plus [[Computer speaker|speakers]]/[[headphones]]\n| network1 = \n| network1rec = \n| hdspace1 = {{unbulleted list|1.5 GB|[[Master boot record]] used{{efn-ua|name=No_GPT_or_UEFI}}}}\n| hdspace1rec = {{Plainlist|\n* +661 MB for Service Pack 1 and 1a{{efn-ua|1={{cite web|title=Hard disk space requirements for Windows XP Service Pack 1|publisher=[[Microsoft]]|date=October 29, 2007|url=https://support.microsoft.com/kb/326583|access-date=April 6, 2012|url-status=live|archive-url=https://web.archive.org/web/20120421100321/http://support.microsoft.com/kb/326583|archive-date=April 21, 2012|author=<!--N/A-->}}}}\n* +1.8 GB for Service Pack 2{{efn-ua|1={{cite web|title=The hard disk space requirements for Windows XP Service Pack 2|publisher=[[Microsoft]]|date=April 18, 2005|url=https://support.microsoft.com/kb/837783|access-date=December 1, 2010|url-status=live|archive-url=https://web.archive.org/web/20101124093717/http://support.microsoft.com/kb/837783|archive-date=November 24, 2010|author=<!--N/A-->}}}}\n* +900 MB for Service Pack 3{{efn-ua|name=technetsp3install|1={{cite web|url=https://technet.microsoft.com/en-us/windowsxp/cc164204.aspx#1|title=Windows XP \u2013 End of Support, Migration Guide, Download \u2013 TechNet|website=technet.microsoft.com|url-status=live|archive-url=https://web.archive.org/web/20080513171653/http://technet.microsoft.com/en-us/windowsxp/cc164204.aspx#1|archive-date=May 13, 2008|date=2007|author=<!--N/A-->}}}}\n}}\n| media1 = [[CD-ROM drive]] or compatible\n| media1rec = \n| display1 = [[Super VGA]] (800 \u00d7 600)\n| display1rec = \n| input1 = [[Computer keyboard|Keyboard]], [[Mouse (computing)|mouse]]\n| input1rec = \n| platform2 = Professional x64 Edition{{efn-ua|1={{cite web|title=Windows XP Professional x64 Edition SP2 VL EN (MSDN-TechNet)|publisher=Programmer Stuffs|date=March 23, 2011|url=http://ismagazine.com/WindowsXPProfessionalx64.aspx|access-date=May 2, 2012|url-status=live|archive-url=https://web.archive.org/web/20140714171953/http://ismagazine.com/WindowsXPProfessionalx64.aspx|archive-date=July 14, 2014}}}}\n| os2 = \n| os2rec = \n| cpu2 = {{unbulleted list|[[x86-64]] or compatible|[[BIOS]] or compatible firmware{{efn-ua|name=No_GPT_or_UEFI}}}}\n| cpu2rec = \n| memory2 = 256 MB\n| memory2rec = \n| gpu2 = \n| gpu2rec = \n| sound2 = N/A\n| sound2rec = [[Sound card]] plus [[Computer speaker|speakers]]/[[headphones]]\n| network2 = \n| network2rec = \n| hdspace2 = {{unbulleted list|1.5 GB|[[Master boot record]] used{{efn-ua|name=No_GPT_or_UEFI}}}}\n| hdspace2rec = \n| media2 = [[CD-ROM drive]] or compatible\n| media2rec = \n| display2 = [[Super VGA]] (800 \u00d7 600)\n| display2rec = \n| input2 = [[Computer keyboard|Keyboard]], [[Mouse (computing)|mouse]]\n| input2rec = \n| platform3 = 64-Bit Edition{{efn-ua|1={{cite web|title=Microsoft Windows XP 64-Bit Edition|work=Microsoft TechNet|publisher=[[Microsoft]]|date=August 15, 2001|url=https://technet.microsoft.com/en-us/library/bb457053.aspx|access-date=May 2, 2012|url-status=live|archive-url=https://web.archive.org/web/20120419104714/http://technet.microsoft.com/en-us/library/bb457053.aspx|archive-date=April 19, 2012|author=<!--N/A-->}}}}\n| os3 = \n| os3rec = \n| cpu3 = [[Itanium]] 733 [[MHz]]\n| cpu3rec = [[Itanium]] 800 [[MHz]]\n| memory3 = 1 GB\n| memory3rec = \n| gpu3 = \n| gpu3rec = \n| sound3 = \n| sound3rec = \n| network3 = \n| network3rec = \n| hdspace3 = 6 GB\n| hdspace3rec = \n| media3 = [[CD-ROM drive]] or compatible\n| media3rec = \n| display3 = [[Super VGA]] (800 \u00d7 600)\n| display3rec = \n| input3 = [[Computer keyboard|Keyboard]], [[Mouse (computing)|mouse]]\n| input3rec = \n}}\n\n {{notelist-ua}}\n\n The maximum amount of RAM that Windows XP can support varies depending on the product edition and the processor architecture. Most 32-bit editions of XP support up to 4 GB, with the exception of Windows XP Starter, which is limited to 512 MB.<ref name="RAMlimitWindows">{{cite web|url=https://www.crucial.com/kb/answer.aspx?qid=3743 |title=What is the maximum amount of RAM the Windows operating system can handle? |publisher=Crucial |access-date=June 25, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110511193445/http://www.crucial.com/kb/answer.aspx?qid=3743 |archive-date=May 11, 2011 |date=<!--N/A-->|author=<!--N/A-->}}</ref> 64-bit editions support up to 128 GB.<ref>{{cite web |url = https://msdn.microsoft.com/en-us/library/windows/desktop/aa366778(v=vs.85).aspx#physical_memory_limits_windows_xp |title = Physical Memory Limits: Windows XP |work = Memory Limits for Windows Releases |publisher = [[Microsoft]] |access-date = January 14, 2014 |url-status = live |archive-url = https://web.archive.org/web/20140106195757/http://msdn.microsoft.com/en-us/library/windows/desktop/aa366778(v=vs.85).aspx#physical_memory_limits_windows_xp |archive-date = January 6, 2014 |df = mdy-all|date=<!--N/A--> |author=<!--N/A-->}}</ref>\n\n Windows XP Professional supports up to two physical processors;<ref>{{cite web |url = https://support.microsoft.com/kb/888732 |title = Processor and memory capabilities of Windows XP Professional x64 Edition and of the x64-based versions of Windows Server 2003 (Revision 7.0) |publisher = [[Microsoft]] |work = Microsoft Support |date = December 20, 2010 |access-date = August 8, 2011 |url-status = live |archive-url = https://web.archive.org/web/20110812043621/http://support.microsoft.com/kb/888732 |archive-date = August 12, 2011 |df = mdy-all |author=<!--N/A-->}}</ref>\nWindows XP Home Edition is limited to one.<ref>{{cite web |last = Kumar |first = I. Suuresh |title = Multi-core processor and multiprocessor limit for Windows XP |work = Microsoft Answers |publisher   = [[Microsoft]] |date = October 25, 2010 |url = https://answers.microsoft.com/en-us/windows/forum/windows_xp-hardware/multi-core-processor-and-multiprocessor-limit-for/abd0a0ce-4ac2-484b-88cb-fbf93beb54e0 |access-date  = April 18, 2014 |url-status = live |archive-url = https://web.archive.org/web/20140419020721/http://answers.microsoft.com/en-us/windows/forum/windows_xp-hardware/multi-core-processor-and-multiprocessor-limit-for/abd0a0ce-4ac2-484b-88cb-fbf93beb54e0 |archive-date = April 19, 2014 |df = mdy-all}}</ref>\n\nHowever, XP supports a greater number of [[logical processor]]s:\n32-bit editions support up to 32 logical processors,<ref>{{cite web |title = Processor Affinity Under WOW64 |work = [[MSDN]] |publisher = [[Microsoft]] |date = January 27, 2011 |url = https://msdn.microsoft.com/en-us/library/aa384228 |access-date = August 8, 2011 |url-status = live |archive-url = https://web.archive.org/web/20110506203054/http://msdn.microsoft.com/en-us/library/aa384228 |archive-date = May 6, 2011 |df = mdy-all|author=<!--N/A-->}}</ref> whereas 64-bit editions support up to 64 logical processors.<ref>{{cite web |url = https://support.microsoft.com/kb/888732 |title = Maximum quantity of logical processors in a PC supported by Microsoft Windows XP professional, x64 edition |publisher = [[Microsoft]] |date = December 20, 2010 |access-date = January 20, 2013 |work = Support |url-status = live |archive-url = https://web.archive.org/web/20130111015952/http://support.microsoft.com/kb/888732 |archive-date = January 11, 2013 |df = mdy-all |author=<!--N/A-->}}</ref>\n\n {{Infobox\n| title=Support status summary\n| headerstyle = background-color: #e8ece4\n| header1 = Expiration date\n| label2 = Mainstream support\n| data2 = {{End date|2009|4|14}}<ref name="lifecycle-db" />\n| label3 = Extended support\n| data3 = {{End date|2014|4|8}}<ref name="lifecycle-db" /> <br /> The official exceptions ended in April 2019.\n| header4 = Applicable [[Windows XP editions|XP editions]]:\n| data5 = Home Edition, Professional Edition, [[Windows XP Professional x64 Edition|Professional x64 Edition]], Professional for Embedded Systems, [[Windows XP Media Center Edition|Media Center Editions]] (all), Starter Edition, Tablet PC Edition and Tablet PC Edition 2005,<ref name="lifecycle-db" /> as well as [[Windows Fundamentals for Legacy PCs]].<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Fundamentals for Legacy PCs|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&qid=&alpha=Windows+Fundamentals+for+Legacy+PCs&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20141005010726/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN|archive-date=October 5, 2014|author=<!--N/A-->|date=<!--N/A-->}}</ref>\n| header6 = Exceptions\n| label7 = [[Windows XP 64-Bit Edition]] ([[Itanium]] edition, including Version 2003)\n|data7 = Mainstream support ended on June 30, 2005<ref>{{cite web |url=https://docs.microsoft.com/en-us/security-updates/securitybulletins/2005/ms05-036 |access-date=April 26, 2018 |date=July 12, 2015 |title=Microsoft Security Bulletin MS05-036 \u2013 Critical |url-status=live |archive-url=https://web.archive.org/web/20180426213340/https://docs.microsoft.com/en-us/security-updates/securitybulletins/2005/ms05-036 |archive-date=April 26, 2018 |author=<!--N/A--> }}</ref>\n| label8 = [[Windows XP Embedded]]\n| data8 = Mainstream support ended on January 11, 2011<ref name="lifecycle-db" /><br />Extended support ended on January 12, 2016<ref name="lifecycle-db" />\n| label9 = [[Windows Embedded for Point of Service]]\n| data9 = Mainstream support ended on April 12, 2011<ref name=WEPOS-Life/><br />Extended support ended on April 12, 2016<ref name=WEPOS-Life>{{cite web|title=Windows XP Embedded Supported for Two or More Years|url=https://redmondmag.com/articles/2014/02/19/windows-xp-embedded-support.aspx|publisher=1105 Media|access-date=June 23, 2018|website=Redmond Magazine|archive-url=https://archive.today/20170220071056/https://redmondmag.com/articles/2014/02/19/windows-xp-embedded-support.aspx|archive-date=February 20, 2017|url-status=live|date=February 19, 2014|first1=Kurt|last1=Mackie}}</ref>\n| label10 = [[Windows Embedded Standard 2009]]\n| data10 = Mainstream support ended on January 14, 2014<br />Extended support ended on January 8, 2019<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Embedded Standard 2009|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+Standard+2009&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20150713174701/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+Standard+2009&Filter=FilterNO|archive-date=July 13, 2015|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n| label11 = [[Windows Embedded POSReady 2009]]\n| data11 = Mainstream support ended on April 8, 2014<br />Extended support ended on April 9, 2019<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Embedded POSReady 2009|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+POSReady+2009&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20141010033141/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+POSReady+2009&Filter=FilterNO|archive-date=October 10, 2014|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n}}\n\nSupport for the original release of Windows XP (without a service pack) ended on August 30, 2005.<ref name="lifecycle-db">{{cite web|title=Microsoft Product Lifecycle Search: Windows XP|url=https://support.microsoft.com/lifecycle/search/default.aspx?alpha=Windows+XP|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20120720010405/http://support.microsoft.com/lifecycle/search/default.aspx?alpha=Windows+XP|archive-date=July 20, 2012|date=<!--N/A-->|author=<!--N/A-->}}</ref> Both Windows XP Service Pack 1 and 1a were retired on October 10, 2006,<ref name="lifecycle-db" /> and both [[Windows 2000]] and Windows XP SP2 reached their end of support on July 13, 2010, about 24 months after the launch of Windows XP Service Pack 3.<ref name="lifecycle-db" /> The company stopped general licensing of Windows XP to OEMs and terminated retail sales of the operating system on June 30, 2008, 17 months after the release of Windows Vista.<ref>{{cite news | url=http://news.cnet.com/Microsoft-extends-Windows-XPs-stay/2100-1016_3-6210524.html | title=Microsoft extends Windows XP's stay | publisher=[[CBS Interactive]] | work=[[CNET]] | date=September 27, 2007 | access-date=June 5, 2008 | url-status=live | archive-url=https://web.archive.org/web/20080830072544/http://news.cnet.com/Microsoft-extends-Windows-XPs-stay/2100-1016_3-6210524.html | archive-date=August 30, 2008 | df=mdy-all |first1=Ina|last1=Fried}}</ref> However, an exception was announced on April 3, 2008, for OEMs producing what it defined as "ultra low-cost personal computers", particularly [[netbook]]s, until one year after the availability of [[Windows 7]] on October 22, 2010. Analysts felt that the move was primarily intended to compete against [[Linux]]-based netbooks, although Microsoft's Kevin Hutz stated that the decision was due to apparent market demand for low-end computers with Windows.<ref>{{cite news|title=Microsoft to keep Windows XP alive\u2014but only for Eee PCs and wannabes |work=[[ComputerWorld]] |publisher=IDG |url=https://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9074720 |access-date=April 8, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080408004318/http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9074720 |archive-date=April 8, 2008 |date=March 3, 2008|first1=Eric|last1=Lai}}</ref>\n\nVariants of Windows XP for [[embedded system]]s have different support policies: Windows XP Embedded SP3 and Windows Embedded for Point of Service SP3 were supported until January and April 2016, respectively. [[Windows Embedded Standard 2009]] and [[Windows Embedded POSReady 2009]] were supported until January and April 2019, respectively.<ref name=zdnet-embeddedsupport>{{cite web|title=Microsoft: 'Remember, some XP-based embedded systems to get support to 2019'|url=https://www.zdnet.com/microsoft-remember-some-xp-based-embedded-systems-to-get-support-to-2019-7000026449/|work=[[ZDNet]]|publisher=[[CBS Interactive]]|access-date=April 6, 2014|url-status=live|archive-url=https://web.archive.org/web/20140404160842/http://www.zdnet.com/microsoft-remember-some-xp-based-embedded-systems-to-get-support-to-2019-7000026449/|archive-date=April 4, 2014|date=February 18, 2014|first1=Liam|last1=Tung}}</ref> These updates, while intended for the embedded editions, could also be downloaded on standard Windows XP with a registry hack, which enabled unofficial patches until April 2019. However, Microsoft advised Windows XP users against installing these fixes, citing incompatibility issues.<ref name="updates2019"/><ref>{{cite news|title=Enthusiast developer keeps Windows XP alive with unofficial 'Service Pack 4' |work=[[PCWorld]] |url=https://www.pcworld.com/article/2599290/enthusiast-developer-keeps-windows-xp-alive-with-unofficial-service-pack-4.html |access-date=October 26, 2018 |url-status=live |archive-url=https://web.archive.org/web/20181026081119/https://www.pcworld.com/article/2599290/enthusiast-developer-keeps-windows-xp-alive-with-unofficial-service-pack-4.html |archive-date=October 26, 2018 |date=August 27, 2014|first1=Jared|last1=Newman}}</ref>\n\n On April 14, 2009, Windows XP exited mainstream support and entered the extended support phase; Microsoft continued to provide security updates every month for Windows XP, however, free technical support, warranty claims, and design changes were no longer being offered. Extended support ended on April 8, 2014, over 12 years after the release of Windows XP; normally Microsoft products have a support life cycle of only 10 years.<ref name="ditchxp">{{cite news|url=http://www.3news.co.nz/Businesses-urged-to-ditch-XP/tabid/412/articleID/293539/Default.aspx|title=Businesses urged to ditch XP|last=Satherley|first=Dan|date=April 9, 2013|work=3 News NZ|access-date=June 28, 2019|archive-url=https://web.archive.org/web/20140713063911/http://www.3news.co.nz/Businesses-urged-to-ditch-XP/tabid/412/articleID/293539/Default.aspx|archive-date=July 13, 2014|url-status=dead}}</ref> Beyond the final security updates released on April 8, no more security patches or support information are provided for XP free-of-charge; "critical patches" will still be created, and made available only to customers subscribing to a paid "Custom Support" plan.<ref>{{cite news | url=https://www.computerworld.com/s/article/9241912/Microsoft_will_craft_XP_patches_after_April_14_but_not_for_you?pageNumber=1 | title=Microsoft will craft XP patches after April '14, but not for you | publisher=IDG | work=[[Computerworld]] | date=August 26, 2013 | access-date=December 12, 2013 | last=Keizer | first=Gregg | url-status=live | archive-url=https://web.archive.org/web/20131020025419/http://www.computerworld.com/s/article/9241912/Microsoft_will_craft_XP_patches_after_April_14_but_not_for_you?pageNumber=1 | archive-date=October 20, 2013 | df=mdy-all }}</ref> As it is a Windows component, all versions of Internet Explorer for Windows XP also became unsupported.<ref name="cw-dumpie">{{cite web|url=https://www.computerworld.com/article/2488477/us-cert-urges-xp-users-to-dump-ie.html|title=US-CERT urges XP users to dump IE|last1=Keizer|first1=Gregg|date=March 11, 2014|work=Computerworld|publisher=IDG|archive-url=https://web.archive.org/web/20190628025857/https://www.computerworld.com/article/2488477/us-cert-urges-xp-users-to-dump-ie.html|archive-date=June 28, 2019|url-status=live|access-date=June 28, 2019}}</ref>\n\nIn January 2014, it was estimated that more than 95% of the 3 million [[automated teller machine]]s in the world were still running Windows XP (which largely replaced [[IBM]]'s [[OS/2]] as the predominant operating system on ATMs); ATMs have an average lifecycle of between seven and ten years, but some have had lifecycles as long as 15. Plans were being made by several ATM vendors and their customers to migrate to Windows 7-based systems over the course of 2014, while vendors have also considered the possibility of using Linux-based platforms in the future to give them more flexibility for support lifecycles, and the [[ATMIA|ATM Industry Association (ATMIA)]] has since endorsed [[Windows 10]] as a further replacement.<ref name=atmia-w10>{{Cite press|url=https://www.atmia.com/news/atmia-position-paper-recommending-migration-to-windows-10/2607/|title=ATMIA position paper recommending migration to Windows 10|publisher=ATM Industry Association|date=June 1, 2015|url-status=live|archive-url=https://web.archive.org/web/20170525045048/https://www.atmia.com/news/atmia-position-paper-recommending-migration-to-windows-10/2607/|archive-date=May 25, 2017|author=ATM Industry Association (collectively)|website=www.atmia.com|language=en}}</ref> However, ATMs typically run the embedded variant of Windows XP, which was supported through January 2016.<ref>{{cite web | url=http://www.businessweek.com/articles/2014-01-16/atms-face-deadline-to-upgrade-from-windows-xp | title=ATMs Face Deadline to Upgrade From Windows XP | publisher=[[Bloomberg L.P.]] | work=[[Bloomberg Businessweek]] | date=January 16, 2014 | access-date=January 17, 2014 | first=Nick | last=Summers | url-status=live | archive-url=https://web.archive.org/web/20140116190619/http://www.businessweek.com/articles/2014-01-16/atms-face-deadline-to-upgrade-from-windows-xp | archive-date=January 16, 2014 | df=mdy-all }}</ref> As of May 2017, around 60% of the 220,000 ATMs in India still run Windows XP.<ref>{{cite web|title=Wannacry ransomware cyber attack: Indian ATMs could be at high risk as most run on Windows XP|url=http://www.businesstoday.in/current/economy-politics/wannacry-ransomware-cyber-attack-indian-atms-high-risk-windows-xp/story/252161.html|website=Business Today|access-date=May 18, 2017|url-status=live|archive-url=https://web.archive.org/web/20170517085703/http://www.businesstoday.in/current/economy-politics/wannacry-ransomware-cyber-attack-indian-atms-high-risk-windows-xp/story/252161.html|archive-date=May 17, 2017|date=May 15, 2017|author=<!--N/A-->}}</ref>\n\nFurthermore, at least 49% of all computers in [[China]] still ran XP at the beginning of 2014. These holdouts were influenced by several factors; prices of genuine copies of later versions of Windows in the country are high, while Ni Guangnan of the [[Chinese Academy of Sciences]] warned that Windows 8 could allegedly expose users to [[Mass surveillance in the United States|surveillance by the United States government]],<ref>{{cite news |title=Windows 8 a 'threat' to China's security |url=https://www.bbc.com/news/technology-27712908 |access-date=October 8, 2018 |publisher=BBC |date=June 5, 2014 |archive-date=October 8, 2018 |archive-url=https://web.archive.org/web/20181008064251/https://www.bbc.com/news/technology-27712908 |url-status=live }}</ref> and the [[Government of China|Chinese government]] would ban the purchase of Windows 8 products for government use in May 2014 in protest of Microsoft's inability to provide "guaranteed" support.<ref>{{cite news |url=http://www.pcworld.com/article/2157220/china-bans-government-purchases-of-windows-8-surprising-microsoft.html |title=China bans government purchases of Windows 8 |date=May 20, 2014 |work=PCWorld |publisher=IDG |access-date=May 20, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140520220932/http://www.pcworld.com/article/2157220/china-bans-government-purchases-of-windows-8-surprising-microsoft.html |archive-date=May 20, 2014 |first1=Michael|last1=Kan}}</ref> The government also had concerns that the impending end of support could affect their [[Copy protection#Anti-piracy|anti-piracy]] initiatives with Microsoft, as users would simply pirate newer versions rather than purchasing them legally. As such, government officials formally requested that Microsoft extend the support period for XP for these reasons. While Microsoft did not comply with their requests, a number of major Chinese software developers, such as Lenovo, [[Kingsoft]] and [[Tencent]], will provide free support and resources for Chinese users migrating from XP.<ref>{{cite web |agency=Reuters |url=http://www.voanews.com/content/reu-microsoft-partners-lenovo-tencent-to-offer-xp-tech-support-in-china/1889658.html |title=Microsoft Partners Lenovo, Tencent to Offer XP Tech Support in China |publisher=Voanews.com |date=April 9, 2014 |access-date=April 16, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140413124242/http://www.voanews.com/content/reu-microsoft-partners-lenovo-tencent-to-offer-xp-tech-support-in-china/1889658.html |archive-date=April 13, 2014 }}</ref> Several governments, in particular those of the Netherlands and the United Kingdom, elected to negotiate "Custom Support" plans with Microsoft for their continued, internal use of Windows XP; the British government's deal lasted for a year, and also covered support for [[Office 2003]] (which reached end-of-life the same day) and cost [[Pound sterling|\u00a3]]5.5 million.<ref name="ars-notdeadyet">{{cite web|url=https://arstechnica.com/information-technology/2014/04/not-dead-yet-dutch-british-governments-pay-to-keep-windows-xp-alive/|title=Not dead yet: Dutch, British governments pay to keep Windows XP alive|last1=Gallagher|first1=Sean|date=April 6, 2014|work=[[Ars Technica]]|publisher=[[Cond\u00e9 Nast|Cond\u00e9 Nast Publications]]|url-status=live|archive-url=https://web.archive.org/web/20191014235635/https://arstechnica.com/information-technology/2014/04/not-dead-yet-dutch-british-governments-pay-to-keep-windows-xp-alive/|archive-date=October 14, 2019|access-date=October 15, 2019}}</ref>\n\nOn March 8, 2014, Microsoft deployed an update for XP that, on the 8th of each month, displays a pop-up notification to remind users about the end of support; however, these notifications may be disabled by the user.<ref name="zdnet-nag">{{cite web|url=https://www.zdnet.com/article/microsoft-to-start-nagging-windows-xp-users-about-april-8-end-of-support-date/|title=Microsoft to start nagging Windows XP users about April 8 end-of-support date|last=Foley|first=Mary Jo|author-link=Mary Jo Foley|date=March 3, 2014|work=[[ZDNet]]|publisher=[[CBS Interactive]]|url-status=live|archive-url=https://web.archive.org/web/20191014235309/https://www.zdnet.com/article/microsoft-to-start-nagging-windows-xp-users-about-april-8-end-of-support-date/|archive-date=October 14, 2019|access-date=October 15, 2019}}</ref> Microsoft also partnered with Laplink to provide a special "express" version of its [[Laplink PCmover|PCmover]] software to help users migrate files and settings from XP to a computer with a newer version of Windows.<ref name="infoworld-laplinkxp">{{cite web|url=https://www.infoworld.com/article/2610199/microsoft--use-laplink-s-windows-xp-migration-tools--not-ours.html|title=Microsoft: Use Laplink's Windows XP migration tools, not ours|last1=Yegulalp|first1=Serdar|date=March 3, 2014|work=Infoworld|url-status=live|archive-url=https://web.archive.org/web/20191015001320/https://www.infoworld.com/article/2610199/microsoft--use-laplink-s-windows-xp-migration-tools--not-ours.html|archive-date=October 15, 2019}}</ref>\n[[File:Electroencephalograph Neurovisor-BMM 40 (close view).jpg|thumb|An [[electroencephalograph]] running on Windows XP. The medical industry's continued use of Windows XP is partly due to medical applications being incompatible with later versions of Windows.]]\nDespite the approaching end of support, there were still notable holdouts that had not migrated past XP; many users elected to remain on XP because of the poor reception of [[Windows Vista]], sales of newer PCs with newer versions of Windows declined because of the [[Great Recession]] and the effects of Vista, and deployments of new versions of Windows in enterprise environments require a large amount of planning, which includes testing applications for compatibility (especially those that are dependent on Internet Explorer 6, which is not compatible with newer versions of Windows).<ref name=bbc-xpwontdie>{{cite web|title=XP \u2013 the operating system that will not die|url=https://www.bbc.com/news/technology-26432473|work=BBC News|access-date=March 25, 2014|url-status=live|archive-url=https://web.archive.org/web/20140324064133/http://www.bbc.com/news/technology-26432473|archive-date=March 24, 2014|date=March 5, 2014|first1=Mark|last1=Ward}}</ref> Major security software vendors (including Microsoft itself) planned to continue offering support and definitions for Windows XP past the end of support to varying extents, along with the developers of [[Google Chrome]], [[Mozilla Firefox]], and [[Opera (web browser)|Opera]] web browsers;<ref name=cw-dumpie/> despite these measures, critics similarly argued that users should eventually migrate from XP to a supported platform.<ref name=pcadvisor-xpsecure>{{cite web|title=What should XP users do when Microsoft ends support? Upgrade to Windows 8, buy a new PC, keep running XP?|url=http://www.pcadvisor.co.uk/how-to/windows/3501239/what-should-xp-users-do-when-microsoft-ends-support/|work=PC Advisor|access-date=April 6, 2014|archive-url=https://web.archive.org/web/20140214073957/http://www.pcadvisor.co.uk/how-to/windows/3501239/what-should-xp-users-do-when-microsoft-ends-support/|archive-date=February 14, 2014 |date=April 7, 2014|first1=Matt|last1=Egan}}</ref> The United States' [[United States Computer Emergency Readiness Team|Computer Emergency Readiness Team]] released an alert in March 2014 advising users of the impending end of support, and informing them that using XP after April 8 may prevent them from meeting US government information security requirements.<ref>{{cite web |url=https://www.us-cert.gov/ncas/alerts/TA14-069A-0 |title=Alert (TA14-069A): Microsoft Ending Support for Windows XP and Office 2003 |date=March 11, 2014 |access-date=April 6, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140316152204/http://www.us-cert.gov/ncas/alerts/TA14-069A-0 |archive-date=March 16, 2014 |author=<!--N/A-->}}</ref>\nMicrosoft continued to provide [[Microsoft Security Essentials|Security Essentials]] [[virus definitions]] and updates for its [[Malicious Software Removal Tool]] (MSRT) for XP until July 14, 2015.<ref>{{cite web | url=https://www.computerworld.com/s/article/9245548/Microsoft_will_furnish_malware_assassin_to_XP_users_until_mid_2015 | title=Microsoft will furnish malware assassin to XP users until mid-2015 | publisher=IDG | work=Computerworld | date=January 19, 2014 | first=Gregg | last=Keizer | url-status=live | archive-url=https://web.archive.org/web/20140122034045/http://www.computerworld.com/s/article/9245548/Microsoft_will_furnish_malware_assassin_to_XP_users_until_mid_2015 | archive-date=January 22, 2014 | df=mdy-all }}</ref> As the end of extended support approached, Microsoft began to increasingly urge XP customers to migrate to newer versions such as Windows 7 or 8 in the interest of security, suggesting that attackers could [[reverse engineer]] security patches for newer versions of Windows and use them to target equivalent vulnerabilities in XP.<ref>{{cite web|title=Microsoft Warns of Permanent Zero-Day Exploits for Windows XP|work=Infosecurity|publisher=Reed Exhibitions|date=August 20, 2013|access-date=August 27, 2013|url=https://www.infosecurity-magazine.com/view/34069/microsoft-warns-of-permanent-zeroday-exploits-for-windows-xp-/|url-status=live|archive-url=https://web.archive.org/web/20130826004304/http://www.infosecurity-magazine.com/view/34069/microsoft-warns-of-permanent-zeroday-exploits-for-windows-xp-/|archive-date=August 26, 2013|author=<!--N/A-->}}</ref> Windows XP is [[Remote code execution|remotely exploitable]] by numerous security holes that were discovered after Microsoft stopped supporting it.<ref>{{cite web|url=https://ics-cert.us-cert.gov/alerts/ICS-ALERT-15-041-01|title=Microsoft Security Bulletin MS15-011 JASBUG|access-date=September 18, 2015|url-status=live|archive-url=https://web.archive.org/web/20150811104408/https://ics-cert.us-cert.gov/alerts/ICS-ALERT-15-041-01|archive-date=August 11, 2015|date=February 10, 2015|author=<!--N/A-->}}</ref><ref>{{cite web|url=https://securityintelligence.com/ibm-x-force-researcher-finds-significant-vulnerability-in-microsoft-windows/#.VGRn6fmsU-V|title=IBM X-Force Researcher Finds Significant Vulnerability in Microsoft Windows|publisher=Securityintelligence.com|access-date=September 18, 2015|url-status=live|archive-url=https://web.archive.org/web/20150703130744/http://securityintelligence.com/ibm-x-force-researcher-finds-significant-vulnerability-in-microsoft-windows/#.VGRn6fmsU-V|archive-date=July 3, 2015|date=November 11, 2014|first1=Robert|last1=Freeman}}</ref>\n\nSimilarly, specialized devices that run XP, particularly [[medical device]]s, must have any revisions to their software\u2014even security updates for the underlying operating system\u2014approved by relevant regulators before they can be released. For this reason, manufacturers often did not allow any updates to devices' operating systems, leaving them open to security exploits and malware.<ref name="mitreview-medicalviruses">{{cite web|last1=Talbot|first1=David|date=October 17, 2012|title=Computer Viruses Are "Rampant" on Medical Devices in Hospitals|url=https://www.technologyreview.com/news/429616/computer-viruses-are-rampant-on-medical-devices-in-hospitals/|url-status=dead|archive-url=https://archive.today/20161019024034/https://www.technologyreview.com/s/429616/computer-viruses-are-rampant-on-medical-devices-in-hospitals/|archive-date=October 19, 2016|access-date=April 6, 2014|work=MIT Technology Review}}</ref>\n\nDespite the end of support for Windows XP, Microsoft has released three emergency security updates for the operating system to patch major security vulnerabilities:\n\n* A patch released in May 2014 to address recently discovered vulnerabilities in Internet Explorer 6 through 11 on all versions of Windows.<ref name="ars-ieemergency">{{cite web|title=Emergency patch for critical IE 0-day throws lifeline to XP laggards, too|url=https://arstechnica.com/security/2014/05/emergency-patch-for-critical-ie-0day-throws-lifeline-to-xp-laggards-too/|website=Ars Technica|publisher=Conde Nast|access-date=May 26, 2017|url-status=live|archive-url=https://web.archive.org/web/20170517085415/https://arstechnica.com/security/2014/05/emergency-patch-for-critical-ie-0day-throws-lifeline-to-xp-laggards-too/|archive-date=May 17, 2017|date=May 1, 2014|first1=Dan|last1=Goodin}}</ref>\n* A patch released in May 2017 to address a vulnerability that was being leveraged by the [[WannaCry ransomware attack]].<ref name="verge-highlyunusual">{{cite web|title=Microsoft issues 'highly unusual' Windows XP patch to prevent massive ransomware attack|url=https://www.theverge.com/2017/5/13/15635006/microsoft-windows-xp-security-patch-wannacry-ransomware-attack|website=The Verge|publisher=Vox Media|access-date=May 13, 2017|url-status=live|archive-url=https://web.archive.org/web/20170514023327/https://www.theverge.com/2017/5/13/15635006/microsoft-windows-xp-security-patch-wannacry-ransomware-attack|archive-date=May 14, 2017|date=May 13, 2017|first1=Tom|last1=Warren}}</ref>\n* A patch released in May 2019 to address a [[BlueKeep|critical code execution vulnerability]] in [[Remote Desktop Services]] which can be exploited in a similar way as the WannaCry vulnerability.<ref name="verge-wannacrylike">{{cite web|title=Microsoft warns of major WannaCry-like Windows security exploit, releases XP patches|url=https://www.theverge.com/2019/5/14/18623565/microsoft-windows-xp-remote-desktop-services-worm-security-patches|website=The Verge|publisher=Vox Media|date=May 14, 2019|access-date=May 16, 2019|first1=Tom|last1=Warren|archive-date=September 2, 2019|archive-url=https://web.archive.org/web/20190902162957/https://www.theverge.com/2019/5/14/18623565/microsoft-windows-xp-remote-desktop-services-worm-security-patches|url-status=live}}</ref><ref>{{Cite web|url=https://blogs.technet.microsoft.com/msrc/2019/05/14/prevent-a-worm-by-updating-remote-desktop-services-cve-2019-0708/|title=Prevent a worm by updating Remote Desktop Services (CVE-2019-0708) \u2013 MSRC|website=blogs.technet.microsoft.com|access-date=May 16, 2019|date=May 14, 2019|archive-date=May 14, 2019|archive-url=https://web.archive.org/web/20190514210409/https://blogs.technet.microsoft.com/msrc/2019/05/14/prevent-a-worm-by-updating-remote-desktop-services-cve-2019-0708/|url-status=live}}</ref>\n\nResearchers reported in August 2019 that Windows 10 users may be at risk for "critical" system compromise because of design flaws of hardware [[device driver]]s from multiple providers.<ref name="FRBS-20190811">{{cite news |last=Winder |first=Davey |title=Critical Windows 10 Warning: Millions Of Users At Risk |url=https://www.forbes.com/sites/daveywinder/2019/08/11/critical-windows-10-warning-confirmed-millions-of-users-are-at-risk/ |date=August 11, 2019 |work=[[Forbes]] |access-date=August 11, 2019 |archive-date=August 11, 2019 |archive-url=https://web.archive.org/web/20190811101251/https://www.forbes.com/sites/daveywinder/2019/08/11/critical-windows-10-warning-confirmed-millions-of-users-are-at-risk/ |url-status=live }}</ref> In the same month, computer experts reported that the [[BlueKeep]] [[Vulnerability (computing)|security vulnerability]], {{CVE|2019-0708}}, that potentially affects older unpatched Microsoft Windows versions via the program's [[Remote Desktop Protocol]], allowing for the possibility of [[remote code execution]], may now include related flaws, collectively named ''[[DejaBlue]]'', affecting newer Windows versions (i.e., [[Windows 7]] and all recent versions) as well.<ref name="WRD-20190813">{{cite news |last=Greenberg |first=Andy |title=DejaBlue: New BlueKeep-Style Bugs Renew The Risk Of A Windows worm |url=https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |date=August 13, 2019 |magazine=[[Wired (magazine)|wired]] |access-date=August 15, 2019 |archive-date=April 13, 2021 |archive-url=https://web.archive.org/web/20210413152701/https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |url-status=live }}</ref> In addition, experts reported a [[Microsoft]] [[security vulnerability]], {{CVE|2019-1162}}, based on [[legacy code]] involving [[Text Services Framework#ctfmon|Microsoft CTF and ctfmon (ctfmon.exe)]], that affects all [[Windows]] versions from the older Windows XP version to the most recent Windows 10 versions; a patch to correct the flaw is currently available.<ref name="TP-20190814">{{cite news |last=Seals |first=Tara |title=20-Year-Old Bug in Legacy Microsoft Code Plagues All Windows Users |url=https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |date=August 14, 2019 |work=ThreatPost.com |access-date=August 15, 2019 |archive-date=April 17, 2021 |archive-url=https://web.archive.org/web/20210417180352/https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |url-status=live }}</ref>\n\nMicrosoft announced in July 2019 that the Microsoft Internet Games services on Windows XP and Windows Me would end on July 31, 2019 (and for Windows 7 on January 22, 2020).<ref>{{Cite web|url=https://answers.microsoft.com/en-us/windows/forum/all/farewell-to-microsoft-internet-games-on-windows-xp/035d5144-6c1b-49bb-b3d5-37f6355fec39?auth=1|title=Farewell to Microsoft Internet Games on Windows XP, Windows ME, and Windows 7|website=answers.microsoft.com|language=en-US|access-date=August 4, 2019|archive-date=July 14, 2019|archive-url=https://web.archive.org/web/20190714150805/https://answers.microsoft.com/en-us/windows/forum/all/farewell-to-microsoft-internet-games-on-windows-xp/035d5144-6c1b-49bb-b3d5-37f6355fec39?auth=1|url-status=live}}</ref> Others, such as [[Steam (service)|Steam]], had done the same, ending support for Windows XP and Windows Vista in January 2019.<ref>{{Cite web|url=https://support.steampowered.com/kb_article.php?ref=1558-AFCM-4577|title=Windows XP and Windows Vista Support \u2013 Steam \u2013 Knowledge Base \u2013 Steam Support|website=support.steampowered.com|access-date=August 4, 2019|archive-date=August 12, 2019|archive-url=https://web.archive.org/web/20190812221829/https://support.steampowered.com/kb_article.php?ref=1558-AFCM-4577|url-status=live}}</ref>\n\nIn 2020, Microsoft announced that it would disable the Windows Update service for SHA-1 endpoints; since Windows XP did not get an update for SHA-2, Windows Update Services are no longer available on the OS as of late July 2020.<ref>{{Cite web|title=Windows Update SHA-1 based endpoints discontinued for older Windows devices|url=https://support.microsoft.com/en-us/topic/windows-update-sha-1-based-endpoints-discontinued-for-older-windows-devices-10b58bd9-5ba2-b23d-498b-139ce5c709af|access-date=2021-04-06|website=support.microsoft.com|archive-date=April 17, 2021|archive-url=https://web.archive.org/web/20210417045726/https://support.microsoft.com/en-us/topic/windows-update-sha-1-based-endpoints-discontinued-for-older-windows-devices-10b58bd9-5ba2-b23d-498b-139ce5c709af|url-status=live}}</ref> However, as of October 2021, the old updates for Windows XP are still available on the [[Microsoft Update Catalog]].<ref>{{Cite web|title=Microsoft Update Catalog|url=https://www.catalog.update.microsoft.com/Search.aspx?q=windows%20xp|access-date=2021-04-06|website=www.catalog.update.microsoft.com|archive-date=April 15, 2021|archive-url=https://web.archive.org/web/20210415024938/https://www.catalog.update.microsoft.com/Search.aspx?q=windows%20xp|url-status=live}}</ref>\n\n{{Timeline Windows XP}}\n\n On release, Windows XP received critical acclaim. [[CNET]] described the operating system as being "worth the hype", considering the new interface to be "spiffier" and more intuitive than previous versions, but feeling that it may "annoy" experienced users with its "hand-holding". XP's expanded multimedia support and CD burning functionality were also noted, along with its streamlined networking tools. The performance improvements of XP in comparison to 2000 and Me were also praised, along with its increased number of built-in device drivers in comparison to 2000. The software compatibility tools were also praised, although it was noted that some programs, particularly older MS-DOS software, may not work correctly on XP because of its differing architecture. They panned Windows XP's new licensing model and product activation system, considering it to be a "slightly annoying roadblock", but acknowledged Microsoft's intent for the changes.<ref name=cnet-xpreview>{{cite web|title=Microsoft Windows XP \u2013 Home Edition review|url=https://www.cnet.com/products/microsoft-windows-xp-home-edition/|archive-url=https://web.archive.org/web/20070531181049/http://reviews.cnet.com/4520-3672_7-5020549-2.html|archive-date=May 31, 2007|work=CNET|access-date=March 25, 2014|date=October 10, 2002|first1=Matt|last1=Lake}}</ref> ''[[PC Magazine]]'' provided similar praise, although noting that a number of its online features were designed to promote Microsoft-owned services, and that aside from quicker boot times, XP's overall performance showed little difference over Windows 2000.<ref name=pcmag-xpreview>{{cite web|title=Microsoft Ships Its Biggest OS Upgrade Ever\u2014Early!|url=https://www.pcmag.com/article2/0,2817,5772,00.asp|work=PC Magazine|access-date=March 25, 2014|url-status=live|archive-url=https://web.archive.org/web/20140325083348/http://www.pcmag.com/article2/0,2817,5772,00.asp|archive-date=March 25, 2014|date=September 3, 2001|first1=Edward|last1=Mendelson |author-link1=Edward Mendelson}}</ref> Windows XP's default theme, Luna, was criticized by some users for its childish look.<ref name="Manes2004">{{cite web|title=Full Disclosure: Your Take on Windows' Worst Irritations|url=http://www.pcworld.com/article/117427/full_disclosure_your_take_on_windows_worst_irritations.html|date=2004-08-26|archive-url=https://web.archive.org/web/20091008081626/http://www.pcworld.com/article/117427/full_disclosure_your_take_on_windows_worst_irritations.html|archive-date=2009-10-08|last=Manes|first=Stephen|author-link=Stephen Manes|work=[[PCWorld]]|publisher=[[International Data Group|IDG]]}}</ref><ref name="Bright2014">{{cite news|url=https://arstechnica.com/information-technology/2014/04/memory-lane-before-everyone-loved-windows-xp-they-hated-it/|newspaper=[[Ars Technica]]|publisher=[[Cond\u00e9 Nast]]|date=2014-04-10|last=Bright|first=Peter|url-status=live|archive-url=https://web.archive.org/web/20140424071600/http://arstechnica.com/information-technology/2014/04/memory-lane-before-everyone-loved-windows-xp-they-hated-it/|title=Memory lane: Before everyone loved Windows XP, they hated it|archive-date=2014-04-24|access-date=2014-06-20}}</ref>\n\nDespite extended support for Windows XP ending in 2014, many users \u2013 including some enterprises \u2013 were reluctant to move away from an operating system they viewed as a stable known quantity despite the many security and functionality improvements in subsequent releases of Windows. Windows XP's longevity was viewed as testament to its stability and Microsoft's successful attempts to keep it up to date, but also as an indictment of its direct successor's [[Criticism of Windows Vista|perceived failings]].<ref name="ArsTenYearsXP">{{cite web |title=Ten years of Windows XP: how longevity became a curse |url=https://arstechnica.com/information-technology/2011/10/ten-years-of-windows-xp-how-longevity-became-a-curse/ |website=Ars Technica |publisher=WIRED Media Group |access-date=June 9, 2018 |url-status=live |archive-url=https://web.archive.org/web/20180612142054/https://arstechnica.com/information-technology/2011/10/ten-years-of-windows-xp-how-longevity-became-a-curse/ |archive-date=June 12, 2018 |date=October 25, 2011|first1=Peter|last1=Bright}}</ref>\n\n {{See also|Usage share of operating systems}}\n\nAccording to [[web analytics]] data generated by [[Net Applications#Market share statistics|Net Applications]], Windows XP was the most widely used operating system until August 2012, when Windows 7 overtook it (later overtaken by [[Windows 10]]),<ref>{{Cite web|url=http://marketshare.hitslink.com:80/operating-system-market-share.aspx?qprid=11&qpcustomb=0|archive-url=https://web.archive.org/web/20120909203552/http://marketshare.hitslink.com/operating-system-market-share.aspx?qprid=11&qpcustomb=0|url-status=dead|archive-date=September 9, 2012|title=Operating system market share|date=September 9, 2012|access-date=September 8, 2018}}</ref> while [[StatCounter]] indicates it happening almost a year earlier.<ref>{{Cite web|url=https://gs.statcounter.com/windows-version-market-share/desktop/worldwide/#monthly-201106-201304|title=Desktop Windows Version Market Share Worldwide|website=StatCounter Global Stats|language=en|access-date=July 2, 2019|archive-date=April 20, 2019|archive-url=https://web.archive.org/web/20190420180627/http://gs.statcounter.com/windows-version-market-share/desktop/worldwide#monthly-201106-201304|url-status=live}}</ref> In January 2014, Net Applications reported a market share of 29.23%<ref>{{cite web | url=http://news.cnet.com/8301-10805_3-57618211-75/oops-windows-xp-gains-in-january-but-so-does-windows-8.1/ | title=Oops, Windows XP gains in January but so does Windows 8.1 | publisher=CBS Interactive | work=CNET | date=February 2, 2014 | access-date=March 16, 2014 | last=Crothers | first=Brooke | url-status=live | archive-url=https://web.archive.org/web/20140221215154/http://news.cnet.com/8301-10805_3-57618211-75/oops-windows-xp-gains-in-january-but-so-does-windows-8.1/ | archive-date=February 21, 2014 | df=mdy-all }}</ref> of "desktop operating systems" for XP (when XP was introduced there was not a separate mobile category to track), while [[W3Schools]] reported a share of 11.0%.<ref name=marketshare>{{cite web|url=https://www.w3schools.com/browsers/browsers_os.asp|title=OS Platform Statistics|publisher=w3schools|access-date=September 14, 2015|url-status=live|archive-url=https://web.archive.org/web/20150917051729/http://www.w3schools.com/browsers/browsers_os.asp|archive-date=September 17, 2015|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n\n{{As of|2021|12}}, in most regions or continents, Windows XP market share on PCs, as a fraction of the total Windows share, has gone below 1% (1.72% in Africa, where it was previously at 0.8%<ref>{{Cite web|title=Desktop Windows Version Market Share Africa|url=https://gs.statcounter.com/windows-version-market-share/desktop/africa/#monthly-202002-202111|access-date=2021-12-11|website=StatCounter Global Stats|language=en|archive-date=April 15, 2021|archive-url=https://web.archive.org/web/20210415025113/https://gs.statcounter.com/windows-version-market-share/desktop/africa/#monthly-202002-202102|url-status=live}}</ref>). XP still has a double-digit market share in a few countries, such as [[Armenia]] at over 50%,<ref name="Armenia">{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#monthly-202007-202111|access-date=2021-12-11|website=StatCounter Global Stats|language=en|archive-date=September 4, 2018|archive-url=https://web.archive.org/web/20180904011320/http://gs.statcounter.com/windows-version-market-share/desktop/armenia/#monthly-202007-202106|url-status=live}}</ref><ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20210401-20210508|access-date=2021-12-11|website=StatCounter Global Stats|language=en}}</ref><ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20210509-20210708|access-date=2021-07-10|website=StatCounter Global Stats|language=en|archive-date=September 4, 2018|archive-url=https://web.archive.org/web/20180904011320/http://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20210509-20210708|url-status=live}}</ref><ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/|access-date=2021-03-02|website=StatCounter Global Stats|language=en|archive-date=September 4, 2018|archive-url=https://web.archive.org/web/20180904011320/http://gs.statcounter.com/windows-version-market-share/desktop/armenia/|url-status=live}}</ref> at 57%, where Windows 7 was highest ranked, and with it being replaced by Windows 10, Windows XP got highest ranked for the longest time, and had over 60% share on some weekends in summer of 2019.<ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20190701-20190915|access-date=2020-07-02|website=StatCounter Global Stats|language=en|archive-date=September 4, 2018|archive-url=https://web.archive.org/web/20180904011320/http://gs.statcounter.com/windows-version-market-share/desktop/armenia/#daily-20190701-20190915|url-status=live}}</ref><ref>{{Cite web|title=Desktop Windows Version Market Share Armenia|url=https://gs.statcounter.com/windows-version-market-share/desktop/armenia/#weekly-202017-202026|access-date=2020-07-02|website=StatCounter Global Stats|language=en|archive-date=September 4, 2018|archive-url=https://web.archive.org/web/20180904011320/http://gs.statcounter.com/windows-version-market-share/desktop/armenia/#weekly-202017-202026|url-status=live}}</ref> <!-- Albania down to 0.5% from 30%, Eritrea (while swings in data) --> <!-- Armenia does show some fluctuation, and while Windows 7 was most popular there in 2017, it has just been gradually replaced by Windows 10, still now XP shows most popular. https://gs.statcounter.com/windows-version-market-share/desktop/albania/#weekly-202015-202024 https://gs.statcounter.com/windows-version-market-share/desktop/eritrea/#weekly-202015-202024 -->\n\n On September 23, 2020, source code for Windows XP with Service Pack 1 and [[Windows Server 2003]] was leaked onto the [[imageboard]] [[4chan]] by an unknown user. Anonymous users managed to compile the code, as well as a Twitter user who posted videos of the process on [[YouTube]] proving that the code was [[Windows Genuine Advantage|genuine]].<ref>{{Cite web|last=Cimpanu|first=Catalin|title=Windows XP leak confirmed after user compiles the leaked code into a working OS|url=https://www.zdnet.com/article/windows-xp-leak-confirmed-after-user-compiles-the-leaked-code-into-a-working-os/|access-date=2020-10-01|website=ZDNet|language=en|archive-date=September 30, 2020|archive-url=https://web.archive.org/web/20200930191933/https://www.zdnet.com/article/windows-xp-leak-confirmed-after-user-compiles-the-leaked-code-into-a-working-os/|url-status=live}}</ref> The videos were later removed on copyright grounds by [[Microsoft]]. The leak was incomplete as it was missing the [[Winlogon]] [[source code]] and some other components.<ref>{{Cite web|last=Warren|first=Tom|date=2020-09-25|title=Windows XP source code leaks online|url=https://www.theverge.com/2020/9/25/21455655/microsoft-windows-xp-source-code-leak|access-date=2020-10-01|website=The Verge|language=en|archive-date=September 29, 2021|archive-url=https://web.archive.org/web/20210929071344/https://www.theverge.com/2020/9/25/21455655/microsoft-windows-xp-source-code-leak|url-status=live}}</ref><ref name="tomshardware">{{Cite web|last=Alcorn|first=Paul|date=September 30, 2020|title=Windows XP Source Code Leaked, Posted to 4chan (Update, It Works)|url=https://www.tomshardware.com/news/working-windows-xp-source-code-posted-to-4chan-update|access-date=2020-10-01|website=Tom's Hardware|language=en|archive-date=October 6, 2021|archive-url=https://web.archive.org/web/20211006095535/https://www.tomshardware.com/news/working-windows-xp-source-code-posted-to-4chan-update|url-status=live}}</ref> The original leak itself was spread using [[Magnet URI scheme|magnet link]]s and torrent files whose payload originally included Server 2003 and XP source code and which was later updated with additional files, among which were previous leaks of Microsoft products, its patents, media about [[conspiracy theories]] on [[Bill Gates]] by [[Vaccine hesitancy|anti-vaccination movements]] and an assortment of PDF files on different topics.<ref>{{Cite web|title=Windows XP Source Code Leaked By Apparent Bill Gates Conspiracist|url=https://gizmodo.com/windows-xp-source-code-leaked-by-apparent-bill-gates-co-1845181128|access-date=2020-10-01|website=Gizmodo|language=en-us|archive-date=October 1, 2020|archive-url=https://web.archive.org/web/20201001165023/https://gizmodo.com/windows-xp-source-code-leaked-by-apparent-bill-gates-co-1845181128|url-status=live}}</ref>\n\nMicrosoft issued a statement stating that it was investigating the leaks.<ref name="tomshardware" /><ref>{{Cite web|url=https://grahamcluley.com/download-windows-xp-source-code-leaks/|title=The Windows XP and Windows Server 2003 source code leaks online|date=September 25, 2020|website=Graham Cluley|access-date=September 29, 2020|archive-date=September 26, 2020|archive-url=https://web.archive.org/web/20200926025455/https://grahamcluley.com/download-windows-xp-source-code-leaks/|url-status=live}}</ref><ref>{{Cite web|url=https://www.computing.co.uk/news/4020805/windows-xp-source-code-leaked|title=Windows XP source code leaked online|date=September 28, 2020|website=www.computing.co.uk|access-date=September 29, 2020|archive-date=October 2, 2020|archive-url=https://web.archive.org/web/20201002194737/https://www.computing.co.uk/news/4020805/windows-xp-source-code-leaked|url-status=live}}</ref>\n\n * [[BlueKeep (security vulnerability)]]\n* [[Comparison of operating systems]]\n* [[History of operating systems]]\n* [[Legacy system]]\n* [[List of operating systems]]\n\n {{Reflist}}\n\n {{Commons category|Microsoft Windows XP}}\n* {{cite book|title=Microsoft Windows XP Plain & Simple|first1=Jerry|last1=Joyce|first2=Marianne|last2=Moon|publisher=[[Microsoft Press]]|year=2004|isbn=978-0-7356-2112-1}}\n\n * [https://www.microsoft.com/en-us/windowsforbusiness/end-of-xp-support Windows XP End of Support]\n* [https://www.microsoft.com/en-us/download/details.aspx?id=55245 Security Update for Windows XP SP3 (KB4012598)]\n\n{{Microsoft Windows family}}\n{{Authority control}}", "Windows XP --- Introduction ---|Development": "{{Main|Development of Windows XP}}\n\nIn the late 1990s, initial development of what would become Windows XP was focused on two individual products: "[[Windows Odyssey|Odyssey]]", which was reportedly intended to succeed the future [[Windows 2000]]; and "[[Microsoft Neptune|Neptune]]", which was reportedly a consumer-oriented operating system using the [[Windows NT]] architecture, succeeding the [[MS-DOS]]-based [[Windows 98]].<ref name="cnet-consolidate">{{cite web | url=http://news.cnet.com/Microsoft-consolidates-Windows-development-efforts/2100-1040_3-236021.html | title=Microsoft consolidates Windows development efforts | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140201144705/http://news.cnet.com/Microsoft-consolidates-Windows-development-efforts/2100-1040_3-236021.html | archive-date=February 1, 2014 | df=mdy-all |date=January 24, 2000|first1=Stephanie|last1=Miles}}</ref>\n\nHowever, the projects proved to be [[Development hell|too ambitious]]. In January 2000, shortly prior to the official release of Windows 2000, technology writer Paul Thurrott reported that Microsoft had shelved both Neptune and Odyssey in favor of a new product codenamed "Whistler", named after [[Whistler, British Columbia]], as many Microsoft employees skied at the [[Whistler-Blackcomb]] ski resort.<ref name=":0">{{cite web | url=http://www.winsupersite.com/faq/longhorn.asp | title=Windows "Longhorn" FAQ | publisher=Penton Media | work=Paul Thurrott's SuperSite for Windows | date=June 22, 2005 | access-date=April 4, 2008 | url-status=dead | archive-url=https://web.archive.org/web/20080404091719/http://www.winsupersite.com/faq/longhorn.asp | archive-date=April 4, 2008 | df=mdy-all | author=<!--N/A--> }}</ref> The goal of Whistler was to unify both the consumer and business-oriented Windows lines under a single, Windows NT platform: Thurrott stated that Neptune had become "a black hole when all the features that were cut from Windows Me were simply re-tagged as Neptune features. And since Neptune and Odyssey would be based on the same code-base anyway, it made sense to combine them into a single project".<ref name="supersite-roadtoxp">{{cite web | url=http://winsupersite.com/article/product-review/the-road-to-gold-the-development-of-windows-xp-reviewed | title=The Road to Gold: The development of Windows XP Reviewed | publisher=Penton Media | work=Paul Thurrott's Supersite for Windows | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140202144509/http://winsupersite.com/article/product-review/the-road-to-gold-the-development-of-windows-xp-reviewed | archive-date=February 2, 2014 | df=mdy-all |date=October 6, 2010|first1=Paul|last1=Thurrott}}</ref>\n\nAt [[Professional Developers Conference|PDC]] on July 13, 2000, Microsoft announced that Whistler would be released during the second half of 2001, and also unveiled the first preview build, 2250, which featured an early implementation of Windows XP's visual styles system and interface changes to Windows Explorer and the Control Panel.<ref name="witpro-betabegins">{{cite web | url=https://www.itprotoday.com/windows-server/introducing-whistler-preview-build-2250 | title=Introducing the Whistler Preview, Build 2250 | publisher=Penton Media | work=Windows IT Pro | access-date=June 9, 2018 | url-status=live | archive-url=https://web.archive.org/web/20180612142613/http://www.itprotoday.com/windows-server/introducing-whistler-preview-build-2250 | archive-date=June 12, 2018 | df=mdy-all |first1=Paul|last1=Thurrott|date=July 17, 2000}}</ref>\n\nMicrosoft released the first public beta build of Whistler, build 2296, on October 31, 2000. Subsequent builds gradually introduced features that users of the release version of Windows XP would recognize, such as [[Internet Explorer 6.0]], the [[Microsoft Product Activation]] system and the ''[[Bliss (image)|Bliss]]'' desktop background.<ref name="supersite-roadtoxp2">{{cite web | url=http://winsupersite.com/article/product-review/the-road-to-gold-part-two | title=The Road to Gold (Part Two) | publisher=Penton Media | work=Paul Thurrott's SuperSite for Windows | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140202144533/http://winsupersite.com/article/product-review/the-road-to-gold-part-two | archive-date=February 2, 2014 | df=mdy-all |date=October 6, 2010|first1=Paul|last1=Thurrott}}</ref>\n\nWhistler was officially unveiled during a media event on February 5, 2001, under the name Windows XP, where XP stands for "eXPerience".<ref name="cnet-xpnamed">{{cite web | url=http://news.cnet.com/Microsoft-to-christen-Windows%2C-Office-with-new-name/2009-1001_3-252047.html | title=Microsoft to christen Windows, Office with new name | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=dead | archive-url=https://web.archive.org/web/20140201144708/http://news.cnet.com/Microsoft-to-christen-Windows%2C-Office-with-new-name/2009-1001_3-252047.html | archive-date=February 1, 2014 | df=mdy-all |date=February 5, 2001|author=<!--N/A-->}}</ref>\n\n In June 2001, Microsoft indicated that it was planning to, in conjunction with [[Intel]] and other PC makers, spend at least 1 billion US dollars on marketing and promoting Windows XP.<ref name="cnet-marketing1bn">{{cite web | url=http://news.cnet.com/2100-1001-269032.html | title=Windows XP marketing tab to hit $1 billion | publisher=CNET Networks | work=CNET | access-date=January 23, 2014 | url-status=live | archive-url=https://web.archive.org/web/20140201144711/http://news.cnet.com/2100-1001-269032.html | archive-date=February 1, 2014 | df=mdy-all |date=January 2, 2002|author=<!--N/A-->}}</ref> The theme of the campaign, "Yes You Can", was designed to emphasize the platform's overall capabilities. Microsoft had originally planned to use the slogan "Prepare to Fly", but it was replaced because of sensitivity issues in the wake of the [[September 11 attacks]].<ref name="Change-XP-slogan">{{cite web |url=https://www.computerworld.co.nz/article/511861/microsoft_changes_xp_slogan_wake_us_attacks/ |title=Microsoft changes XP slogan in wake of US attacks |work=Computerworld NZ |publisher=IDG |access-date=August 7, 2015 |url-status=live |archive-url=https://web.archive.org/web/20150905135939/http://www.computerworld.co.nz/article/511861/microsoft_changes_xp_slogan_wake_us_attacks/ |archive-date=September 5, 2015}}</ref>\n\nOn August 24, 2001, Windows XP build 2600 was [[Release to manufacturing|released to manufacturing]] (RTM). During a ceremonial media event at [[Microsoft Redmond Campus]], copies of the RTM build were given to representatives of several major PC manufacturers in [[briefcase]]s, who then flew off on decorated [[helicopter]]s. While PC manufacturers would be able to release devices running XP beginning on September 24, 2001, XP was expected to reach general, retail availability on October 25, 2001. On the same day, Microsoft also announced the final retail pricing of XP's two main editions, "Home" (as a replacement for [[Windows Me]] for home computing) and "Professional" (as a replacement for [[Windows 2000]] for high-end users).<ref name="supersite-roadtoxp3">{{cite web |url=http://winsupersite.com/article/product-review/the-road-to-gold-part-three | title=The Road to Gold (Part Three) | publisher=Penton Media | work=Paul Thurrott's Supersite for Windows | access-date=March 11, 2017| archive-url=https://web.archive.org/web/20170829035957/http://winsupersite.com/article/product-review/the-road-to-gold-part-three |archive-date=August 29, 2017 | url-status=dead|date=October 15, 2001|first1=Paul|last1=Thurrott}}</ref>", "Windows XP --- Introduction ---|Support lifecycle": "{{Infobox\n| title=Support status summary\n| headerstyle = background-color: #e8ece4\n| header1 = Expiration date\n| label2 = Mainstream support\n| data2 = {{End date|2009|4|14}}<ref name="lifecycle-db" />\n| label3 = Extended support\n| data3 = {{End date|2014|4|8}}<ref name="lifecycle-db" /> <br /> The official exceptions ended in April 2019.\n| header4 = Applicable [[Windows XP editions|XP editions]]:\n| data5 = Home Edition, Professional Edition, [[Windows XP Professional x64 Edition|Professional x64 Edition]], Professional for Embedded Systems, [[Windows XP Media Center Edition|Media Center Editions]] (all), Starter Edition, Tablet PC Edition and Tablet PC Edition 2005,<ref name="lifecycle-db" /> as well as [[Windows Fundamentals for Legacy PCs]].<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Fundamentals for Legacy PCs|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&qid=&alpha=Windows+Fundamentals+for+Legacy+PCs&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20141005010726/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN|archive-date=October 5, 2014|author=<!--N/A-->|date=<!--N/A-->}}</ref>\n| header6 = Exceptions\n| label7 = [[Windows XP 64-Bit Edition]] ([[Itanium]] edition, including Version 2003)\n|data7 = Mainstream support ended on June 30, 2005<ref>{{cite web |url=https://docs.microsoft.com/en-us/security-updates/securitybulletins/2005/ms05-036 |access-date=April 26, 2018 |date=July 12, 2015 |title=Microsoft Security Bulletin MS05-036 \u2013 Critical |url-status=live |archive-url=https://web.archive.org/web/20180426213340/https://docs.microsoft.com/en-us/security-updates/securitybulletins/2005/ms05-036 |archive-date=April 26, 2018 |author=<!--N/A--> }}</ref>\n| label8 = [[Windows XP Embedded]]\n| data8 = Mainstream support ended on January 11, 2011<ref name="lifecycle-db" /><br />Extended support ended on January 12, 2016<ref name="lifecycle-db" />\n| label9 = [[Windows Embedded for Point of Service]]\n| data9 = Mainstream support ended on April 12, 2011<ref name=WEPOS-Life/><br />Extended support ended on April 12, 2016<ref name=WEPOS-Life>{{cite web|title=Windows XP Embedded Supported for Two or More Years|url=https://redmondmag.com/articles/2014/02/19/windows-xp-embedded-support.aspx|publisher=1105 Media|access-date=June 23, 2018|website=Redmond Magazine|archive-url=https://archive.today/20170220071056/https://redmondmag.com/articles/2014/02/19/windows-xp-embedded-support.aspx|archive-date=February 20, 2017|url-status=live|date=February 19, 2014|first1=Kurt|last1=Mackie}}</ref>\n| label10 = [[Windows Embedded Standard 2009]]\n| data10 = Mainstream support ended on January 14, 2014<br />Extended support ended on January 8, 2019<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Embedded Standard 2009|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+Standard+2009&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20150713174701/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+Standard+2009&Filter=FilterNO|archive-date=July 13, 2015|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n| label11 = [[Windows Embedded POSReady 2009]]\n| data11 = Mainstream support ended on April 8, 2014<br />Extended support ended on April 9, 2019<ref>{{cite web|title=Microsoft Product Lifecycle Search: Windows Embedded POSReady 2009|url=https://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+POSReady+2009&Filter=FilterNO|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20141010033141/http://support2.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=Windows+Embedded+POSReady+2009&Filter=FilterNO|archive-date=October 10, 2014|date=<!--N/A-->|author=<!--N/A-->}}</ref>\n}}\n\nSupport for the original release of Windows XP (without a service pack) ended on August 30, 2005.<ref name="lifecycle-db">{{cite web|title=Microsoft Product Lifecycle Search: Windows XP|url=https://support.microsoft.com/lifecycle/search/default.aspx?alpha=Windows+XP|work=Microsoft Support|publisher=[[Microsoft]]|access-date=October 13, 2012|url-status=live|archive-url=https://web.archive.org/web/20120720010405/http://support.microsoft.com/lifecycle/search/default.aspx?alpha=Windows+XP|archive-date=July 20, 2012|date=<!--N/A-->|author=<!--N/A-->}}</ref> Both Windows XP Service Pack 1 and 1a were retired on October 10, 2006,<ref name="lifecycle-db" /> and both [[Windows 2000]] and Windows XP SP2 reached their end of support on July 13, 2010, about 24 months after the launch of Windows XP Service Pack 3.<ref name="lifecycle-db" /> The company stopped general licensing of Windows XP to OEMs and terminated retail sales of the operating system on June 30, 2008, 17 months after the release of Windows Vista.<ref>{{cite news | url=http://news.cnet.com/Microsoft-extends-Windows-XPs-stay/2100-1016_3-6210524.html | title=Microsoft extends Windows XP's stay | publisher=[[CBS Interactive]] | work=[[CNET]] | date=September 27, 2007 | access-date=June 5, 2008 | url-status=live | archive-url=https://web.archive.org/web/20080830072544/http://news.cnet.com/Microsoft-extends-Windows-XPs-stay/2100-1016_3-6210524.html | archive-date=August 30, 2008 | df=mdy-all |first1=Ina|last1=Fried}}</ref> However, an exception was announced on April 3, 2008, for OEMs producing what it defined as "ultra low-cost personal computers", particularly [[netbook]]s, until one year after the availability of [[Windows 7]] on October 22, 2010. Analysts felt that the move was primarily intended to compete against [[Linux]]-based netbooks, although Microsoft's Kevin Hutz stated that the decision was due to apparent market demand for low-end computers with Windows.<ref>{{cite news|title=Microsoft to keep Windows XP alive\u2014but only for Eee PCs and wannabes |work=[[ComputerWorld]] |publisher=IDG |url=https://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9074720 |access-date=April 8, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080408004318/http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9074720 |archive-date=April 8, 2008 |date=March 3, 2008|first1=Eric|last1=Lai}}</ref>\n\nVariants of Windows XP for [[embedded system]]s have different support policies: Windows XP Embedded SP3 and Windows Embedded for Point of Service SP3 were supported until January and April 2016, respectively. [[Windows Embedded Standard 2009]] and [[Windows Embedded POSReady 2009]] were supported until January and April 2019, respectively.<ref name=zdnet-embeddedsupport>{{cite web|title=Microsoft: 'Remember, some XP-based embedded systems to get support to 2019'|url=https://www.zdnet.com/microsoft-remember-some-xp-based-embedded-systems-to-get-support-to-2019-7000026449/|work=[[ZDNet]]|publisher=[[CBS Interactive]]|access-date=April 6, 2014|url-status=live|archive-url=https://web.archive.org/web/20140404160842/http://www.zdnet.com/microsoft-remember-some-xp-based-embedded-systems-to-get-support-to-2019-7000026449/|archive-date=April 4, 2014|date=February 18, 2014|first1=Liam|last1=Tung}}</ref> These updates, while intended for the embedded editions, could also be downloaded on standard Windows XP with a registry hack, which enabled unofficial patches until April 2019. However, Microsoft advised Windows XP users against installing these fixes, citing incompatibility issues.<ref name="updates2019"/><ref>{{cite news|title=Enthusiast developer keeps Windows XP alive with unofficial 'Service Pack 4' |work=[[PCWorld]] |url=https://www.pcworld.com/article/2599290/enthusiast-developer-keeps-windows-xp-alive-with-unofficial-service-pack-4.html |access-date=October 26, 2018 |url-status=live |archive-url=https://web.archive.org/web/20181026081119/https://www.pcworld.com/article/2599290/enthusiast-developer-keeps-windows-xp-alive-with-unofficial-service-pack-4.html |archive-date=October 26, 2018 |date=August 27, 2014|first1=Jared|last1=Newman}}</ref>\n\n On April 14, 2009, Windows XP exited mainstream support and entered the extended support phase; Microsoft continued to provide security updates every month for Windows XP, however, free technical support, warranty claims, and design changes were no longer being offered. Extended support ended on April 8, 2014, over 12 years after the release of Windows XP; normally Microsoft products have a support life cycle of only 10 years.<ref name="ditchxp">{{cite news|url=http://www.3news.co.nz/Businesses-urged-to-ditch-XP/tabid/412/articleID/293539/Default.aspx|title=Businesses urged to ditch XP|last=Satherley|first=Dan|date=April 9, 2013|work=3 News NZ|access-date=June 28, 2019|archive-url=https://web.archive.org/web/20140713063911/http://www.3news.co.nz/Businesses-urged-to-ditch-XP/tabid/412/articleID/293539/Default.aspx|archive-date=July 13, 2014|url-status=dead}}</ref> Beyond the final security updates released on April 8, no more security patches or support information are provided for XP free-of-charge; "critical patches" will still be created, and made available only to customers subscribing to a paid "Custom Support" plan.<ref>{{cite news | url=https://www.computerworld.com/s/article/9241912/Microsoft_will_craft_XP_patches_after_April_14_but_not_for_you?pageNumber=1 | title=Microsoft will craft XP patches after April '14, but not for you | publisher=IDG | work=[[Computerworld]] | date=August 26, 2013 | access-date=December 12, 2013 | last=Keizer | first=Gregg | url-status=live | archive-url=https://web.archive.org/web/20131020025419/http://www.computerworld.com/s/article/9241912/Microsoft_will_craft_XP_patches_after_April_14_but_not_for_you?pageNumber=1 | archive-date=October 20, 2013 | df=mdy-all }}</ref> As it is a Windows component, all versions of Internet Explorer for Windows XP also became unsupported.<ref name="cw-dumpie">{{cite web|url=https://www.computerworld.com/article/2488477/us-cert-urges-xp-users-to-dump-ie.html|title=US-CERT urges XP users to dump IE|last1=Keizer|first1=Gregg|date=March 11, 2014|work=Computerworld|publisher=IDG|archive-url=https://web.archive.org/web/20190628025857/https://www.computerworld.com/article/2488477/us-cert-urges-xp-users-to-dump-ie.html|archive-date=June 28, 2019|url-status=live|access-date=June 28, 2019}}</ref>\n\nIn January 2014, it was estimated that more than 95% of the 3 million [[automated teller machine]]s in the world were still running Windows XP (which largely replaced [[IBM]]'s [[OS/2]] as the predominant operating system on ATMs); ATMs have an average lifecycle of between seven and ten years, but some have had lifecycles as long as 15. Plans were being made by several ATM vendors and their customers to migrate to Windows 7-based systems over the course of 2014, while vendors have also considered the possibility of using Linux-based platforms in the future to give them more flexibility for support lifecycles, and the [[ATMIA|ATM Industry Association (ATMIA)]] has since endorsed [[Windows 10]] as a further replacement.<ref name=atmia-w10>{{Cite press|url=https://www.atmia.com/news/atmia-position-paper-recommending-migration-to-windows-10/2607/|title=ATMIA position paper recommending migration to Windows 10|publisher=ATM Industry Association|date=June 1, 2015|url-status=live|archive-url=https://web.archive.org/web/20170525045048/https://www.atmia.com/news/atmia-position-paper-recommending-migration-to-windows-10/2607/|archive-date=May 25, 2017|author=ATM Industry Association (collectively)|website=www.atmia.com|language=en}}</ref> However, ATMs typically run the embedded variant of Windows XP, which was supported through January 2016.<ref>{{cite web | url=http://www.businessweek.com/articles/2014-01-16/atms-face-deadline-to-upgrade-from-windows-xp | title=ATMs Face Deadline to Upgrade From Windows XP | publisher=[[Bloomberg L.P.]] | work=[[Bloomberg Businessweek]] | date=January 16, 2014 | access-date=January 17, 2014 | first=Nick | last=Summers | url-status=live | archive-url=https://web.archive.org/web/20140116190619/http://www.businessweek.com/articles/2014-01-16/atms-face-deadline-to-upgrade-from-windows-xp | archive-date=January 16, 2014 | df=mdy-all }}</ref> As of May 2017, around 60% of the 220,000 ATMs in India still run Windows XP.<ref>{{cite web|title=Wannacry ransomware cyber attack: Indian ATMs could be at high risk as most run on Windows XP|url=http://www.businesstoday.in/current/economy-politics/wannacry-ransomware-cyber-attack-indian-atms-high-risk-windows-xp/story/252161.html|website=Business Today|access-date=May 18, 2017|url-status=live|archive-url=https://web.archive.org/web/20170517085703/http://www.businesstoday.in/current/economy-politics/wannacry-ransomware-cyber-attack-indian-atms-high-risk-windows-xp/story/252161.html|archive-date=May 17, 2017|date=May 15, 2017|author=<!--N/A-->}}</ref>\n\nFurthermore, at least 49% of all computers in [[China]] still ran XP at the beginning of 2014. These holdouts were influenced by several factors; prices of genuine copies of later versions of Windows in the country are high, while Ni Guangnan of the [[Chinese Academy of Sciences]] warned that Windows 8 could allegedly expose users to [[Mass surveillance in the United States|surveillance by the United States government]],<ref>{{cite news |title=Windows 8 a 'threat' to China's security |url=https://www.bbc.com/news/technology-27712908 |access-date=October 8, 2018 |publisher=BBC |date=June 5, 2014 |archive-date=October 8, 2018 |archive-url=https://web.archive.org/web/20181008064251/https://www.bbc.com/news/technology-27712908 |url-status=live }}</ref> and the [[Government of China|Chinese government]] would ban the purchase of Windows 8 products for government use in May 2014 in protest of Microsoft's inability to provide "guaranteed" support.<ref>{{cite news |url=http://www.pcworld.com/article/2157220/china-bans-government-purchases-of-windows-8-surprising-microsoft.html |title=China bans government purchases of Windows 8 |date=May 20, 2014 |work=PCWorld |publisher=IDG |access-date=May 20, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140520220932/http://www.pcworld.com/article/2157220/china-bans-government-purchases-of-windows-8-surprising-microsoft.html |archive-date=May 20, 2014 |first1=Michael|last1=Kan}}</ref> The government also had concerns that the impending end of support could affect their [[Copy protection#Anti-piracy|anti-piracy]] initiatives with Microsoft, as users would simply pirate newer versions rather than purchasing them legally. As such, government officials formally requested that Microsoft extend the support period for XP for these reasons. While Microsoft did not comply with their requests, a number of major Chinese software developers, such as Lenovo, [[Kingsoft]] and [[Tencent]], will provide free support and resources for Chinese users migrating from XP.<ref>{{cite web |agency=Reuters |url=http://www.voanews.com/content/reu-microsoft-partners-lenovo-tencent-to-offer-xp-tech-support-in-china/1889658.html |title=Microsoft Partners Lenovo, Tencent to Offer XP Tech Support in China |publisher=Voanews.com |date=April 9, 2014 |access-date=April 16, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140413124242/http://www.voanews.com/content/reu-microsoft-partners-lenovo-tencent-to-offer-xp-tech-support-in-china/1889658.html |archive-date=April 13, 2014 }}</ref> Several governments, in particular those of the Netherlands and the United Kingdom, elected to negotiate "Custom Support" plans with Microsoft for their continued, internal use of Windows XP; the British government's deal lasted for a year, and also covered support for [[Office 2003]] (which reached end-of-life the same day) and cost [[Pound sterling|\u00a3]]5.5 million.<ref name="ars-notdeadyet">{{cite web|url=https://arstechnica.com/information-technology/2014/04/not-dead-yet-dutch-british-governments-pay-to-keep-windows-xp-alive/|title=Not dead yet: Dutch, British governments pay to keep Windows XP alive|last1=Gallagher|first1=Sean|date=April 6, 2014|work=[[Ars Technica]]|publisher=[[Cond\u00e9 Nast|Cond\u00e9 Nast Publications]]|url-status=live|archive-url=https://web.archive.org/web/20191014235635/https://arstechnica.com/information-technology/2014/04/not-dead-yet-dutch-british-governments-pay-to-keep-windows-xp-alive/|archive-date=October 14, 2019|access-date=October 15, 2019}}</ref>\n\nOn March 8, 2014, Microsoft deployed an update for XP that, on the 8th of each month, displays a pop-up notification to remind users about the end of support; however, these notifications may be disabled by the user.<ref name="zdnet-nag">{{cite web|url=https://www.zdnet.com/article/microsoft-to-start-nagging-windows-xp-users-about-april-8-end-of-support-date/|title=Microsoft to start nagging Windows XP users about April 8 end-of-support date|last=Foley|first=Mary Jo|author-link=Mary Jo Foley|date=March 3, 2014|work=[[ZDNet]]|publisher=[[CBS Interactive]]|url-status=live|archive-url=https://web.archive.org/web/20191014235309/https://www.zdnet.com/article/microsoft-to-start-nagging-windows-xp-users-about-april-8-end-of-support-date/|archive-date=October 14, 2019|access-date=October 15, 2019}}</ref> Microsoft also partnered with Laplink to provide a special "express" version of its [[Laplink PCmover|PCmover]] software to help users migrate files and settings from XP to a computer with a newer version of Windows.<ref name="infoworld-laplinkxp">{{cite web|url=https://www.infoworld.com/article/2610199/microsoft--use-laplink-s-windows-xp-migration-tools--not-ours.html|title=Microsoft: Use Laplink's Windows XP migration tools, not ours|last1=Yegulalp|first1=Serdar|date=March 3, 2014|work=Infoworld|url-status=live|archive-url=https://web.archive.org/web/20191015001320/https://www.infoworld.com/article/2610199/microsoft--use-laplink-s-windows-xp-migration-tools--not-ours.html|archive-date=October 15, 2019}}</ref>\n[[File:Electroencephalograph Neurovisor-BMM 40 (close view).jpg|thumb|An [[electroencephalograph]] running on Windows XP. The medical industry's continued use of Windows XP is partly due to medical applications being incompatible with later versions of Windows.]]\nDespite the approaching end of support, there were still notable holdouts that had not migrated past XP; many users elected to remain on XP because of the poor reception of [[Windows Vista]], sales of newer PCs with newer versions of Windows declined because of the [[Great Recession]] and the effects of Vista, and deployments of new versions of Windows in enterprise environments require a large amount of planning, which includes testing applications for compatibility (especially those that are dependent on Internet Explorer 6, which is not compatible with newer versions of Windows).<ref name=bbc-xpwontdie>{{cite web|title=XP \u2013 the operating system that will not die|url=https://www.bbc.com/news/technology-26432473|work=BBC News|access-date=March 25, 2014|url-status=live|archive-url=https://web.archive.org/web/20140324064133/http://www.bbc.com/news/technology-26432473|archive-date=March 24, 2014|date=March 5, 2014|first1=Mark|last1=Ward}}</ref> Major security software vendors (including Microsoft itself) planned to continue offering support and definitions for Windows XP past the end of support to varying extents, along with the developers of [[Google Chrome]], [[Mozilla Firefox]], and [[Opera (web browser)|Opera]] web browsers;<ref name=cw-dumpie/> despite these measures, critics similarly argued that users should eventually migrate from XP to a supported platform.<ref name=pcadvisor-xpsecure>{{cite web|title=What should XP users do when Microsoft ends support? Upgrade to Windows 8, buy a new PC, keep running XP?|url=http://www.pcadvisor.co.uk/how-to/windows/3501239/what-should-xp-users-do-when-microsoft-ends-support/|work=PC Advisor|access-date=April 6, 2014|archive-url=https://web.archive.org/web/20140214073957/http://www.pcadvisor.co.uk/how-to/windows/3501239/what-should-xp-users-do-when-microsoft-ends-support/|archive-date=February 14, 2014 |date=April 7, 2014|first1=Matt|last1=Egan}}</ref> The United States' [[United States Computer Emergency Readiness Team|Computer Emergency Readiness Team]] released an alert in March 2014 advising users of the impending end of support, and informing them that using XP after April 8 may prevent them from meeting US government information security requirements.<ref>{{cite web |url=https://www.us-cert.gov/ncas/alerts/TA14-069A-0 |title=Alert (TA14-069A): Microsoft Ending Support for Windows XP and Office 2003 |date=March 11, 2014 |access-date=April 6, 2014 |url-status=live |archive-url=https://web.archive.org/web/20140316152204/http://www.us-cert.gov/ncas/alerts/TA14-069A-0 |archive-date=March 16, 2014 |author=<!--N/A-->}}</ref>\nMicrosoft continued to provide [[Microsoft Security Essentials|Security Essentials]] [[virus definitions]] and updates for its [[Malicious Software Removal Tool]] (MSRT) for XP until July 14, 2015.<ref>{{cite web | url=https://www.computerworld.com/s/article/9245548/Microsoft_will_furnish_malware_assassin_to_XP_users_until_mid_2015 | title=Microsoft will furnish malware assassin to XP users until mid-2015 | publisher=IDG | work=Computerworld | date=January 19, 2014 | first=Gregg | last=Keizer | url-status=live | archive-url=https://web.archive.org/web/20140122034045/http://www.computerworld.com/s/article/9245548/Microsoft_will_furnish_malware_assassin_to_XP_users_until_mid_2015 | archive-date=January 22, 2014 | df=mdy-all }}</ref> As the end of extended support approached, Microsoft began to increasingly urge XP customers to migrate to newer versions such as Windows 7 or 8 in the interest of security, suggesting that attackers could [[reverse engineer]] security patches for newer versions of Windows and use them to target equivalent vulnerabilities in XP.<ref>{{cite web|title=Microsoft Warns of Permanent Zero-Day Exploits for Windows XP|work=Infosecurity|publisher=Reed Exhibitions|date=August 20, 2013|access-date=August 27, 2013|url=https://www.infosecurity-magazine.com/view/34069/microsoft-warns-of-permanent-zeroday-exploits-for-windows-xp-/|url-status=live|archive-url=https://web.archive.org/web/20130826004304/http://www.infosecurity-magazine.com/view/34069/microsoft-warns-of-permanent-zeroday-exploits-for-windows-xp-/|archive-date=August 26, 2013|author=<!--N/A-->}}</ref> Windows XP is [[Remote code execution|remotely exploitable]] by numerous security holes that were discovered after Microsoft stopped supporting it.<ref>{{cite web|url=https://ics-cert.us-cert.gov/alerts/ICS-ALERT-15-041-01|title=Microsoft Security Bulletin MS15-011 JASBUG|access-date=September 18, 2015|url-status=live|archive-url=https://web.archive.org/web/20150811104408/https://ics-cert.us-cert.gov/alerts/ICS-ALERT-15-041-01|archive-date=August 11, 2015|date=February 10, 2015|author=<!--N/A-->}}</ref><ref>{{cite web|url=https://securityintelligence.com/ibm-x-force-researcher-finds-significant-vulnerability-in-microsoft-windows/#.VGRn6fmsU-V|title=IBM X-Force Researcher Finds Significant Vulnerability in Microsoft Windows|publisher=Securityintelligence.com|access-date=September 18, 2015|url-status=live|archive-url=https://web.archive.org/web/20150703130744/http://securityintelligence.com/ibm-x-force-researcher-finds-significant-vulnerability-in-microsoft-windows/#.VGRn6fmsU-V|archive-date=July 3, 2015|date=November 11, 2014|first1=Robert|last1=Freeman}}</ref>\n\nSimilarly, specialized devices that run XP, particularly [[medical device]]s, must have any revisions to their software\u2014even security updates for the underlying operating system\u2014approved by relevant regulators before they can be released. For this reason, manufacturers often did not allow any updates to devices' operating systems, leaving them open to security exploits and malware.<ref name="mitreview-medicalviruses">{{cite web|last1=Talbot|first1=David|date=October 17, 2012|title=Computer Viruses Are "Rampant" on Medical Devices in Hospitals|url=https://www.technologyreview.com/news/429616/computer-viruses-are-rampant-on-medical-devices-in-hospitals/|url-status=dead|archive-url=https://archive.today/20161019024034/https://www.technologyreview.com/s/429616/computer-viruses-are-rampant-on-medical-devices-in-hospitals/|archive-date=October 19, 2016|access-date=April 6, 2014|work=MIT Technology Review}}</ref>\n\nDespite the end of support for Windows XP, Microsoft has released three emergency security updates for the operating system to patch major security vulnerabilities:\n\n* A patch released in May 2014 to address recently discovered vulnerabilities in Internet Explorer 6 through 11 on all versions of Windows.<ref name="ars-ieemergency">{{cite web|title=Emergency patch for critical IE 0-day throws lifeline to XP laggards, too|url=https://arstechnica.com/security/2014/05/emergency-patch-for-critical-ie-0day-throws-lifeline-to-xp-laggards-too/|website=Ars Technica|publisher=Conde Nast|access-date=May 26, 2017|url-status=live|archive-url=https://web.archive.org/web/20170517085415/https://arstechnica.com/security/2014/05/emergency-patch-for-critical-ie-0day-throws-lifeline-to-xp-laggards-too/|archive-date=May 17, 2017|date=May 1, 2014|first1=Dan|last1=Goodin}}</ref>\n* A patch released in May 2017 to address a vulnerability that was being leveraged by the [[WannaCry ransomware attack]].<ref name="verge-highlyunusual">{{cite web|title=Microsoft issues 'highly unusual' Windows XP patch to prevent massive ransomware attack|url=https://www.theverge.com/2017/5/13/15635006/microsoft-windows-xp-security-patch-wannacry-ransomware-attack|website=The Verge|publisher=Vox Media|access-date=May 13, 2017|url-status=live|archive-url=https://web.archive.org/web/20170514023327/https://www.theverge.com/2017/5/13/15635006/microsoft-windows-xp-security-patch-wannacry-ransomware-attack|archive-date=May 14, 2017|date=May 13, 2017|first1=Tom|last1=Warren}}</ref>\n* A patch released in May 2019 to address a [[BlueKeep|critical code execution vulnerability]] in [[Remote Desktop Services]] which can be exploited in a similar way as the WannaCry vulnerability.<ref name="verge-wannacrylike">{{cite web|title=Microsoft warns of major WannaCry-like Windows security exploit, releases XP patches|url=https://www.theverge.com/2019/5/14/18623565/microsoft-windows-xp-remote-desktop-services-worm-security-patches|website=The Verge|publisher=Vox Media|date=May 14, 2019|access-date=May 16, 2019|first1=Tom|last1=Warren|archive-date=September 2, 2019|archive-url=https://web.archive.org/web/20190902162957/https://www.theverge.com/2019/5/14/18623565/microsoft-windows-xp-remote-desktop-services-worm-security-patches|url-status=live}}</ref><ref>{{Cite web|url=https://blogs.technet.microsoft.com/msrc/2019/05/14/prevent-a-worm-by-updating-remote-desktop-services-cve-2019-0708/|title=Prevent a worm by updating Remote Desktop Services (CVE-2019-0708) \u2013 MSRC|website=blogs.technet.microsoft.com|access-date=May 16, 2019|date=May 14, 2019|archive-date=May 14, 2019|archive-url=https://web.archive.org/web/20190514210409/https://blogs.technet.microsoft.com/msrc/2019/05/14/prevent-a-worm-by-updating-remote-desktop-services-cve-2019-0708/|url-status=live}}</ref>\n\nResearchers reported in August 2019 that Windows 10 users may be at risk for "critical" system compromise because of design flaws of hardware [[device driver]]s from multiple providers.<ref name="FRBS-20190811">{{cite news |last=Winder |first=Davey |title=Critical Windows 10 Warning: Millions Of Users At Risk |url=https://www.forbes.com/sites/daveywinder/2019/08/11/critical-windows-10-warning-confirmed-millions-of-users-are-at-risk/ |date=August 11, 2019 |work=[[Forbes]] |access-date=August 11, 2019 |archive-date=August 11, 2019 |archive-url=https://web.archive.org/web/20190811101251/https://www.forbes.com/sites/daveywinder/2019/08/11/critical-windows-10-warning-confirmed-millions-of-users-are-at-risk/ |url-status=live }}</ref> In the same month, computer experts reported that the [[BlueKeep]] [[Vulnerability (computing)|security vulnerability]], {{CVE|2019-0708}}, that potentially affects older unpatched Microsoft Windows versions via the program's [[Remote Desktop Protocol]], allowing for the possibility of [[remote code execution]], may now include related flaws, collectively named ''[[DejaBlue]]'', affecting newer Windows versions (i.e., [[Windows 7]] and all recent versions) as well.<ref name="WRD-20190813">{{cite news |last=Greenberg |first=Andy |title=DejaBlue: New BlueKeep-Style Bugs Renew The Risk Of A Windows worm |url=https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |date=August 13, 2019 |magazine=[[Wired (magazine)|wired]] |access-date=August 15, 2019 |archive-date=April 13, 2021 |archive-url=https://web.archive.org/web/20210413152701/https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |url-status=live }}</ref> In addition, experts reported a [[Microsoft]] [[security vulnerability]], {{CVE|2019-1162}}, based on [[legacy code]] involving [[Text Services Framework#ctfmon|Microsoft CTF and ctfmon (ctfmon.exe)]], that affects all [[Windows]] versions from the older Windows XP version to the most recent Windows 10 versions; a patch to correct the flaw is currently available.<ref name="TP-20190814">{{cite news |last=Seals |first=Tara |title=20-Year-Old Bug in Legacy Microsoft Code Plagues All Windows Users |url=https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |date=August 14, 2019 |work=ThreatPost.com |access-date=August 15, 2019 |archive-date=April 17, 2021 |archive-url=https://web.archive.org/web/20210417180352/https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |url-status=live }}</ref>\n\nMicrosoft announced in July 2019 that the Microsoft Internet Games services on Windows XP and Windows Me would end on July 31, 2019 (and for Windows 7 on January 22, 2020).<ref>{{Cite web|url=https://answers.microsoft.com/en-us/windows/forum/all/farewell-to-microsoft-internet-games-on-windows-xp/035d5144-6c1b-49bb-b3d5-37f6355fec39?auth=1|title=Farewell to Microsoft Internet Games on Windows XP, Windows ME, and Windows 7|website=answers.microsoft.com|language=en-US|access-date=August 4, 2019|archive-date=July 14, 2019|archive-url=https://web.archive.org/web/20190714150805/https://answers.microsoft.com/en-us/windows/forum/all/farewell-to-microsoft-internet-games-on-windows-xp/035d5144-6c1b-49bb-b3d5-37f6355fec39?auth=1|url-status=live}}</ref> Others, such as [[Steam (service)|Steam]], had done the same, ending support for Windows XP and Windows Vista in January 2019.<ref>{{Cite web|url=https://support.steampowered.com/kb_article.php?ref=1558-AFCM-4577|title=Windows XP and Windows Vista Support \u2013 Steam \u2013 Knowledge Base \u2013 Steam Support|website=support.steampowered.com|access-date=August 4, 2019|archive-date=August 12, 2019|archive-url=https://web.archive.org/web/20190812221829/https://support.steampowered.com/kb_article.php?ref=1558-AFCM-4577|url-status=live}}</ref>\n\nIn 2020, Microsoft announced that it would disable the Windows Update service for SHA-1 endpoints; since Windows XP did not get an update for SHA-2, Windows Update Services are no longer available on the OS as of late July 2020.<ref>{{Cite web|title=Windows Update SHA-1 based endpoints discontinued for older Windows devices|url=https://support.microsoft.com/en-us/topic/windows-update-sha-1-based-endpoints-discontinued-for-older-windows-devices-10b58bd9-5ba2-b23d-498b-139ce5c709af|access-date=2021-04-06|website=support.microsoft.com|archive-date=April 17, 2021|archive-url=https://web.archive.org/web/20210417045726/https://support.microsoft.com/en-us/topic/windows-update-sha-1-based-endpoints-discontinued-for-older-windows-devices-10b58bd9-5ba2-b23d-498b-139ce5c709af|url-status=live}}</ref> However, as of October 2021, the old updates for Windows XP are still available on the [[Microsoft Update Catalog]].<ref>{{Cite web|title=Microsoft Update Catalog|url=https://www.catalog.update.microsoft.com/Search.aspx?q=windows%20xp|access-date=2021-04-06|website=www.catalog.update.microsoft.com|archive-date=April 15, 2021|archive-url=https://web.archive.org/web/20210415024938/https://www.catalog.update.microsoft.com/Search.aspx?q=windows%20xp|url-status=live}}</ref>\n\n{{Timeline Windows XP}}", "Windows XP --- Introduction ---|Source code leak": "On September 23, 2020, source code for Windows XP with Service Pack 1 and [[Windows Server 2003]] was leaked onto the [[imageboard]] [[4chan]] by an unknown user. Anonymous users managed to compile the code, as well as a Twitter user who posted videos of the process on [[YouTube]] proving that the code was [[Windows Genuine Advantage|genuine]].<ref>{{Cite web|last=Cimpanu|first=Catalin|title=Windows XP leak confirmed after user compiles the leaked code into a working OS|url=https://www.zdnet.com/article/windows-xp-leak-confirmed-after-user-compiles-the-leaked-code-into-a-working-os/|access-date=2020-10-01|website=ZDNet|language=en|archive-date=September 30, 2020|archive-url=https://web.archive.org/web/20200930191933/https://www.zdnet.com/article/windows-xp-leak-confirmed-after-user-compiles-the-leaked-code-into-a-working-os/|url-status=live}}</ref> The videos were later removed on copyright grounds by [[Microsoft]]. The leak was incomplete as it was missing the [[Winlogon]] [[source code]] and some other components.<ref>{{Cite web|last=Warren|first=Tom|date=2020-09-25|title=Windows XP source code leaks online|url=https://www.theverge.com/2020/9/25/21455655/microsoft-windows-xp-source-code-leak|access-date=2020-10-01|website=The Verge|language=en|archive-date=September 29, 2021|archive-url=https://web.archive.org/web/20210929071344/https://www.theverge.com/2020/9/25/21455655/microsoft-windows-xp-source-code-leak|url-status=live}}</ref><ref name="tomshardware">{{Cite web|last=Alcorn|first=Paul|date=September 30, 2020|title=Windows XP Source Code Leaked, Posted to 4chan (Update, It Works)|url=https://www.tomshardware.com/news/working-windows-xp-source-code-posted-to-4chan-update|access-date=2020-10-01|website=Tom's Hardware|language=en|archive-date=October 6, 2021|archive-url=https://web.archive.org/web/20211006095535/https://www.tomshardware.com/news/working-windows-xp-source-code-posted-to-4chan-update|url-status=live}}</ref> The original leak itself was spread using [[Magnet URI scheme|magnet link]]s and torrent files whose payload originally included Server 2003 and XP source code and which was later updated with additional files, among which were previous leaks of Microsoft products, its patents, media about [[conspiracy theories]] on [[Bill Gates]] by [[Vaccine hesitancy|anti-vaccination movements]] and an assortment of PDF files on different topics.<ref>{{Cite web|title=Windows XP Source Code Leaked By Apparent Bill Gates Conspiracist|url=https://gizmodo.com/windows-xp-source-code-leaked-by-apparent-bill-gates-co-1845181128|access-date=2020-10-01|website=Gizmodo|language=en-us|archive-date=October 1, 2020|archive-url=https://web.archive.org/web/20201001165023/https://gizmodo.com/windows-xp-source-code-leaked-by-apparent-bill-gates-co-1845181128|url-status=live}}</ref>\n\nMicrosoft issued a statement stating that it was investigating the leaks.<ref name="tomshardware" /><ref>{{Cite web|url=https://grahamcluley.com/download-windows-xp-source-code-leaks/|title=The Windows XP and Windows Server 2003 source code leaks online|date=September 25, 2020|website=Graham Cluley|access-date=September 29, 2020|archive-date=September 26, 2020|archive-url=https://web.archive.org/web/20200926025455/https://grahamcluley.com/download-windows-xp-source-code-leaks/|url-status=live}}</ref><ref>{{Cite web|url=https://www.computing.co.uk/news/4020805/windows-xp-source-code-leaked|title=Windows XP source code leaked online|date=September 28, 2020|website=www.computing.co.uk|access-date=September 29, 2020|archive-date=October 2, 2020|archive-url=https://web.archive.org/web/20201002194737/https://www.computing.co.uk/news/4020805/windows-xp-source-code-leaked|url-status=live}}</ref>"}},
{"article_title": "Audio Video Interleave", "pageid": "36715", "revid": "1060140848", "timestamp": "2021-12-13T18:31:14Z", "history_paths": [["Audio Video Interleave --- Introduction ---", "History"]], "categories": ["computer-related introductions in 1992", "digital container formats", "microsoft windows multimedia technology"], "heading_tree": {"Audio Video Interleave --- Introduction ---": {"History": {}, "Format": {}, "Metadata": {}, "Limitations": {}, "DV AVI": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Audio Video Interleave --- Introduction ---|History": "Publishers faced a predicament regarding how they should distribute videos on [[CD-ROM]]s. Thirty seconds of video displayed in [[24-bit color]] and at thirty [[frame rate|frames per second]] and [[Super VGA]] resolutions could take up 680 [[megabyte]]s of space\u2014the storage capacity of most CD-ROMs in 1992. [[Lossy compression|Lossily compressing]] the videos would save a lot of space, but not without degrading the quality of the videos. Publishers who were more concerned about video quality instead were searching for an ideal compression algorithm that would compress the video files while still preserving the quality.<ref name=Raskin-1992>{{cite magazine|url=https://books.google.com/books?id=v9TVJ_G_sk8C&pg=PA345|title=27 Good Reasons To Buy A CD-ROM Player|last=Raskin|first=Robin|work=[[PC Magazine]]|date=1992-12-22|access-date=2021-09-19|volume=11|issue=22|pages=345\u2013346}}</ref>\n\nMicrosoft recognized the problem and sought to develop a standard that would [[lossless compression|losslessly compress]] the video files. It also recognized that because of the hardware requirements for playing the videos in uncompressed quality, which at the time were demanding, it needed to allow users of low-end computers to play the videos in compressed quality. It developed and published the Audio Video Interleave format on November 10, 1992, as part of its Video for Windows, and included support for [[codec]]s to satisfy those users.<ref name=Raskin-1992/><ref>{{cite magazine|url=https://books.google.com/books?id=KlEEAAAAMBAJ&pg=PA3|title=Microsoft, vendors team up to air Video for Windows|last1=Damore|first1=Kelley|last2=Corcoran|first2=Cate|work=[[InfoWorld]]|date=1992-11-09|access-date=2021-09-19|volume=14|issue=45|page=3}}</ref><ref name=Quain-1993>{{cite magazine|url=https://books.google.com/books?id=LIyy_CtozLcC&pg=PA39|title=Microsoft Goes Hollywood With Video for Windows|last=Quain|first=John R.|work=[[PC Magazine]]|date=1993-01-12|access-date=2021-09-19|volume=12|issue=1|page=39}}</ref>"}},
{"article_title": "Ion thruster", "pageid": "37839", "revid": "1063086811", "timestamp": "2022-01-01T04:30:19Z", "history_paths": [["Ion thruster --- Introduction ---", "Origins"]], "categories": ["magnetic propulsion devices", "ion engines", "emerging technologies", "spacecraft propulsion"], "heading_tree": {"Ion thruster --- Introduction ---": {"Origins": {}, "General working principle": {}, "Electrostatic thrusters": {"Gridded electrostatic ion thrusters": {}, "Hall effect thrusters": {}, "Field-emission electric propulsion": {}}, "Electromagnetic thrusters": {"Pulsed inductive thrusters": {}, "Magnetoplasmadynamic thruster": {}, "Electrodeless plasma thrusters": {}, "Helicon double layer thrusters": {}, "Variable Specific Impulse Magnetoplasma Rocket (VASIMR)": {}, "Microwave electrothermal thrusters": {}}, "Radioisotope thruster": {}, "Comparisons": {}, "Lifetime": {"Gridded thruster life": {}, "Hall-effect thruster life": {}}, "Propellants": {}, "Energy efficiency": {}, "Missions": {"Demonstration vehicles": {"SERT": {}}, "Operational missions": {"In Earth orbit": {"Tiangong space station": {}, "Starlink": {}, "GOCE": {}}, "In deep space": {"Deep Space 1": {}, "Hayabusa": {}, "Smart 1": {}, "Dawn": {}}, "LISA Pathfinder": {}, "BepiColombo": {}, "Double Asteroid Redirection Test": {}}, "Proposed missions": {"International Space Station": {}, "Lunar Gateway": {}, "MARS-CAT": {}, "Interstellar missions": {}}}, "Popular culture": {}, "See also": {}, "References": {"Bibliography": {}}, "External links": {"Articles": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Ion thruster --- Introduction ---|Origins": "[[File:SERT-1 spacecraft.jpg|thumb|290px|right|SERT-1 spacecraft]]\n\nThe first person who wrote a paper introducing the idea publicly was [[Konstantin Tsiolkovsky]] in 1911.<ref name="choueiri2">{{cite web |title=Ion Propulsion \u2014 Over 50 Years in the Making |url=http://science.nasa.gov/newhome/headlines/prop06apr99_2.htm |work=Science@NASA |url-status=dead |archive-url=https://web.archive.org/web/20100327120759/http://science.nasa.gov/newhome/headlines/prop06apr99_2.htm |archive-date=2010-03-27}}</ref> The technique was recommended for near-vacuum conditions at high altitude, but thrust was demonstrated with ionized air streams at atmospheric pressure. The idea appeared again in [[Hermann Oberth]]'s "''Wege zur Raumschiffahrt''" (Ways to Spaceflight), published in 1923, where he explained his thoughts on the mass savings of electric propulsion, predicted its use in [[spacecraft propulsion]] and [[attitude control]], and advocated electrostatic acceleration of charged gasses.<ref name="choueiri3">{{cite web |url=http://alfven.princeton.edu/publications/choueiri-jpp-2004 |title=A Critical History of Electric Propulsion: The First 50 Years (1906\u20131956) |access-date=2016-10-18 |first= E. Y. |last=Choueiri}}</ref>\n\nA working ion thruster was built by [[Harold R. Kaufman]] in 1959 at the [[NASA]] [[Glenn Research Center]] facilities. It was similar to a gridded electrostatic ion thruster and used [[mercury (element)|mercury]] for propellant. Suborbital tests were conducted during the 1960s and in 1964, the engine was sent into a suborbital flight aboard the [[SERT-1|Space Electric Rocket Test-1]] (SERT-1).<ref name='Ion 1964'>{{cite web |url=http://www.nasa.gov/centers/glenn/about/history/ds1.html |title=Contributions to Deep Space 1 |publisher=NASA}} {{PD-notice}}</ref><ref name="Cybulski">{{cite web |first1=Ronald J. |last1=Cybulski |first2=Daniel M. |last2=Shellhammer |first3=Robert R. |last3=Lovell |first4=Edward J. |last4=Domino |first5=Joseph T. |last5=Kotnik |url=https://ntrs.nasa.gov/api/citations/19650009681/downloads/19650009681.pdf |title=Results from SERT I Ion Rocket Flight Test |id=NASA-TN-D-2718 |publisher=[[NASA]] |date=1965}}{{PD-notice}}</ref> It successfully operated for the planned 31 minutes before falling to Earth.<ref name="Glenn">{{cite web |url=http://www.nasa.gov/centers/glenn/about/fs08grc.html |title=Innovative Engines - Glenn Ion Propulsion Research Tames the Challenges of 21st Century Space Travel |access-date=2007-11-19 |url-status=dead |archive-url=https://web.archive.org/web/20070915023928/http://www.nasa.gov/centers/glenn/about/fs08grc.html |archive-date=2007-09-15}} {{PD-notice}}</ref> This test was followed by an orbital test, SERT-2, in 1970.<ref name="sert2">{{cite web |publisher=[[NASA Glenn Research Center]] |url=http://www.grc.nasa.gov/WWW/ion/past/70s/sert2.htm |title=Space Electric Rocket Test II (SERT II) |archive-url=https://web.archive.org/web/20110927004353/http://www.grc.nasa.gov/WWW/ion/past/70s/sert2.htm |archive-date=2011-09-27 |url-status=dead |access-date=1 July 2010}}{{PD-notice}}</ref><ref>[http://www.astronautix.com/craft/sert.htm SERT] {{webarchive |url=https://web.archive.org/web/20101025005136/http://www.astronautix.com/craft/sert.htm |date=2010-10-25}} page at Astronautix (Accessed on 1 July 2010)</ref>\n\nAn alternate form of electric propulsion, the [[Hall effect thruster]], was studied independently in the [[United States]] and the [[Soviet Union]] in the 1950s and 1960s. Hall effect thrusters operated on Soviet satellites from 1972 until the late 1990s, mainly used for satellite stabilization in north\u2013south and in east\u2013west directions. Some 100\u2013200 engines completed missions on Soviet and [[Russia]]n satellites.<ref name="NK">{{cite web |url=http://novosti-kosmonavtiki.ru/content/numbers/198/35.shtml |title=Native Electric Propulsion Engines Today |publisher=Novosti Kosmonavtiki |date=1999\n|issue=7 |archive-url=https://web.archive.org/web/20110606033558/http://www.novosti-kosmonavtiki.ru/content/numbers/198/35.shtml |archive-date=6 June 2011 |language=ru}}</ref> Soviet thruster design was introduced to the West in 1992 after a team of electric propulsion specialists, under the support of the [[Ballistic Missile Defense Organization]], visited Soviet laboratories."}},
{"article_title": "Nuclear electric rocket", "pageid": "37843", "revid": "1025480824", "timestamp": "2021-05-27T20:10:35Z", "history_paths": [["Nuclear electric rocket --- Introduction ---", "History"]], "categories": ["nuclear spacecraft propulsion", "nuclear technology"], "heading_tree": {"Nuclear electric rocket --- Introduction ---": {"Conceptual overview": {}, "History": {"NASA": {}, "Russia": {}}, "Concepts": {"Pebble bed reactor combined with gas turbine": {}, "Novel electric propulsion concepts": {}, "Electrical generation": {}}, "Other types of nuclear power concepts in space": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Nuclear electric rocket --- Introduction ---|History": "In 2001, the [[Safe affordable fission engine]] was under development, with a tested 30 kW nuclear heat source intended to lead to the development of a 400 kW thermal reactor with [[Brayton cycle]] gas turbines to produce electric power. Waste heat rejection was intended to be accomplished using low-mass [[heat pipe]] technology. Safety was intended to be assured by a rugged design.{{citation_needed|date=July 2019}}\n\n[[Project Prometheus]] was an early 2000s [[NASA]] study on nuclear electric spacecraft.{{citation_needed|date=July 2019}}\n\n[[Kilopower]] is the latest NASA reactor development program, but is intended for surface use only.{{citation_needed|date=July 2019}}\n\n see [[TEM (nuclear propulsion)]]\nThe TEM project started in 2009 with the goal of powering a Mars engine.\n\nMarch 2016 - First batch of nuclear fuel received{{Citation needed|date=November 2020}}"}},
{"article_title": "Mass driver", "pageid": "37844", "revid": "1062229610", "timestamp": "2021-12-27T04:51:20Z", "history_paths": [["Mass driver --- Introduction ---", "Practical attempts"]], "categories": ["magnetic devices", "magnetic propulsion devices", "space colonization", "spacecraft propulsion", "non-rocket spacelaunch", "emerging technologies"], "heading_tree": {"Mass driver --- Introduction ---": {"Fixed mass drivers": {"On Earth": {}}, "Spacecraft-based mass drivers": {}, "Hybrid mass drivers": {}, "Mass drivers as weapons": {}, "Practical attempts": {}, "See also": {"People": {}}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Mass driver --- Introduction ---|Practical attempts": "<!-- Deleted image removed: [[File:Northrup Electric Gun.png|thumb|140px|Edwin Northrup's 1937 Electric Gun Mass Driver]] -->\n\nOne of the first engineering descriptions of an "Electric Gun" appears in the technical supplement of the 1937 science fiction novel "Zero to Eighty" by "Akkad Pseudoman",<ref>{{cite book|last=Pseudoman|first=Akkad|title=Zero to Eighty|date=1937|publisher=Princeton University Press|location=Princeton, New Jersey}}</ref> a pen name for the Princeton physicist and electrical entrepreneur [[Edwin Fitch Northrup]].  Dr. Northrup built prototype coil guns powered by kHz-frequency three-phase electrical generators, and the book contains photographs of some of these prototypes.  The book describes a fictional circumnavigation of the moon by a two-person vehicle launched by a Northrup electric gun.\n\nLater prototype mass drivers have been built since 1976 ([[Mass Driver 1]]), some constructed by the U.S. [[Space Studies Institute]] in order to prove their properties and practicality.  [[Coilgun#Potential uses|Military R&D on coilguns]] is related, as are [[maglev|maglev trains]].\n\n[[SpinLaunch]], a company founded in 2014, conducted the initial test of their test accelerator in October 2021.<ref>{{Cite web|last=Sheetz|first=Michael|date=2021-11-09|title=Alternative rocket builder SpinLaunch completes first test flight|url=https://www.cnbc.com/2021/11/09/spinlaunch-completes-first-test-flight-of-alternative-rocket.html|access-date=2021-11-11|website=CNBC|language=en}}</ref>"}},
{"article_title": "Hot-air balloon", "pageid": "38173", "revid": "1062726639", "timestamp": "2021-12-30T04:31:48Z", "history_paths": [["Hot-air balloon --- Introduction ---", "History"]], "categories": ["balloons (aeronautics)", "airship technology", "symbols of new mexico", "french inventions", "18th-century inventions"], "heading_tree": {"Hot-air balloon --- Introduction ---": {"History": {"Premodern and unmanned balloons": {}, "First manned flight": {}, "Modern balloons": {}, "Records": {}}, "Construction": {"Envelope": {"Seams": {}, "Coatings": {}, "Sizes and capacity": {}, "Vents": {}, "Shape": {}}, "Basket": {}, "Burner": {}, "Fuel tanks": {}, "Instrumentation": {}, "Combined mass": {}}, "Theory of operation": {"Generating lift": {"Montgolfier": {}, "Hybrid": {}, "Solar": {}}, "Steering": {}}, "Safety equipment": {"In the basket": {}, "On the occupants": {}, "On the ground crew": {}}, "Maintenance and repair": {"Maintenance": {}, "Repair": {}}, "Licensing": {"Balloons": {}, "Pilots": {"In Australia": {}, "In the UK": {}, "In the United States": {}}}, "Accidents and incidents": {}, "Manufacturers": {}, "See also": {}, "References": {}, "External links": {"General ballooning sites": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Hot-air balloon --- Introduction ---|History": "{{Main|History of ballooning}}\n\n [[File:SkyLanternRichy01.jpg|thumb|upright|A [[sky lantern]]]]\n\nA precursor of the hot-air balloon was the [[sky lantern]] ({{zh|s=\u5b54\u660e\u706f|t=\u5b54\u660e\u71c8}}). [[Zhuge Liang]] of the [[Shu Han]] kingdom, during the [[Three Kingdoms]] era (220\u2013280 CE), used these airborne lanterns for military signaling.<ref>{{cite book |url=https://books.google.com/books?id=ssO_19TRQ9AC&q=Kongming+balloon&pg=PA112 |title=Ancient Chinese Inventions |last=Deng |first=Yinke |location=Beijing |publisher=China Intercontinental Press |year=2005|isbn=9787508508375 }}, cited in Joel Serr\u00e3o, ''Dicion\u00e1rio de Hist\u00f3ria de Portugal'', Vol III. Porto: Livraria Figueirinhas, 1981, 184\u2013185.</ref>\n\nIn the 18th century the Portuguese Jesuit priest [[Bartolomeu de Gusm\u00e3o]] envisioned an aerial apparatus called {{lang|pt|Passarola}}, which was the predecessor of the hot-air balloon. The purpose of {{lang|pt|Passarola}} was to serve as air vessel in order to facilitate communication and as a strategical device.<ref>Arquivo Nacional da Torre do Tombo. "Cartas Consultas e Mais Obras de Alexandre de Gusm\u00e3o" (p\u00e1ginas do manuscrito 201\u2013209).</ref> In 1709 [[John V of Portugal]] decided to fund Bartolomeu de Gusm\u00e3o's project following a petition made by the Jesuit priest,<ref>{{Cite web |url=http://purl.pt/706 |title=Reproduction fac-simil\u00e9 d'un dessin \u00e0 la plume de sa description et de la p\u00e9tition adress\u00e9e au Jean V. (de Portugal) en langue latine et en \u00e9criture contemporaine (1709) retrouv\u00e9s r\u00e9cemment dans les archives du Vatican du c\u00e9l\u00e8bre a\u00e9ronef de Bartholomeu Lourenco de Gusm\u00e3o "l'homme volant" portugais, n\u00e9 au Br\u00e9sil (1685-1724) pr\u00e9curseur des navigateurs a\u00e9riens et premier inventeur des a\u00e9rostats. 1917 |last=De Gusm\u00e3o |first=Bartolomeu}}</ref> and an unmanned demonstration was performed at [[Casa da \u00cdndia|Casa da India]] in presence of John V, the queen [[Maria Anna of Austria]], having as witnesses the Italian cardinal [[Pope Innocent XIII|Michelangelo Conti]], two members of the Portuguese Royal Academy of History, one Portuguese diplomat and one chronicler. This event would bring some European attention to this event and this project. A later article dated on October 20, 1786 by the London ''Daily Universal Register'' would state that the inventor was able to raise himself by the use of his prototype. Also in 1709, the Portuguese Jesuit wrote {{lang|pt|Manifesto summ\u00e1rio para os que ignoram poderse navegar pelo elemento do ar}} (''Short Manifesto for those who are unaware that is possible to sail through the element air''); he also left designs for a manned air vessel.\n\nThe notable balloonist [[Julian Nott (balloonist)|Julian Nott]], in the 1970s; hypothesized that two millennia ago, the [[Nazca Lines]] [[geoglyph]]s' creation could have been guided by [[Nazca culture|Nazca leaders]] in a balloon, possibly the earliest hot-air balloon flights in human history. <ref>{{cite web|url=http://www.nott.com/Pages/projects.php |title=Innovative Projects; The Extraordinary Nazca Prehistoric Balloon|accessdate=2017-07-24|url-status=dead|archiveurl=https://web.archive.org/web/20110714201319/http://www.nott.com/Pages/projects.php |archivedate=2011-07-14 }}</ref>   In 1975 to support this theory, he designed and piloted the Nazca Prehistoric Balloon, using only methods and materials available to the Pre-Inca Peruvians 1,000 years ago.  <ref>{{Cite web|url=http://www.ltaflightmagazine.com/julian-nott-bizarre-accident|title = Scientist and Aviator Julian Nott Dies After a Bizarre Accident | LTA-Flight Magazine}}</ref><ref>{{cite news |title=BALLOONIST HAS HIGH HOPES BUT NO ILLUSIONS |url=https://www.nytimes.com/1986/11/18/science/balloonist-has-high-hopes-but-no-illusions.html |newspaper=The New York Times |date=18 November 1986 |accessdate=21 June 2020|last1=Browne |first1=Malcolm W. }}</ref>\n\n [[File:Montgolfier Balloon.JPG|thumb|upright|A model of the Montgolfier brothers' balloon at the [[London Science Museum]]]]\nThe French brothers Joseph-Michel and Jacques-\u00c9tienne [[Montgolfier brothers|Montgolfier]] developed a hot-air balloon in [[Annonay]], Ardeche, [[France]], and demonstrated it publicly on September 19, 1783, making an unmanned flight lasting 10 minutes. After experimenting with unmanned balloons and flights with animals, the first balloon flight with humans aboard, a tethered flight, performed on or around October 15, 1783, by Jean-Francois Pilatre de Rozier, who made at least one tethered flight from the yard of the Reveillon workshop in the [[Faubourg Saint-Antoine]]. Later that same day, Pilatre de Rozier became the second human to ascend into the air, reaching an altitude of {{convert|26|m|abbr=on}}, the length of the tether.<ref>{{Cite book |title=Guinness world records 2014 |last=Glenday |first=Craig |year=2013 |isbn=978-1-908843-15-9 |url-access=registration |url=https://archive.org/details/guinnessworldrec0000unse_r3e7}}</ref><ref>Tom D. Crouch (2009). Lighter Than Air.</ref> The first free flight with human passengers was made a few weeks later, on November 21, 1783.<ref>{{cite web |url=http://www.centennialofflight.gov/essay/Lighter_than_air/Early_Balloon_Flight_in_Europe/LTA1.htm |title=U.S. Centennial of Flight Commission: Early Balloon Flight in Europe |access-date=2008-06-04 |url-status=dead |archive-url=https://web.archive.org/web/20080602012700/http://www.centennialofflight.gov/essay/Lighter_than_air/Early_Balloon_Flight_in_Europe/LTA1.htm |archive-date=2008-06-02}}</ref> [[Louis XVI of France|King Louis XVI]] had originally decreed that condemned criminals would be the first [[Aviator|pilots]], but de Rozier, along with [[Fran\u00e7ois Laurent d'Arlandes|Marquis Fran\u00e7ois d'Arlandes]], petitioned successfully for the honor.<ref>{{cite web |url=http://www.start-flying.com/Montgolfier.htm |title=Start-Flying: History of Balloon Flying |publisher=www.start-flying.com |access-date=2007-12-28}}</ref><ref>{{cite web |url=http://www.chm.bris.ac.uk/webprojects2003/hetherington/final/montgolfier_bros.html |title=Lighter than air: The Montgolfier Brothers | access-date=2007-12-28}}</ref><ref>{{cite web |url=http://www.nasm.si.edu/exhibitions/gal109/NEWHTF/ITM300.HTM |title=National Air and Space Museum: Pioneers of Flight gallery |access-date=2007-12-28}}</ref>\nThe [[History of military ballooning|first military use]] of a hot-air balloon happened in 1794 during the [[Battle of Fleurus (1794)|battle of Fleurus]], when the French used the balloon {{lang|fr|l'Entreprenant}} for observation.<ref>{{cite web |url=http://www.crwflags.com/fotw/flags/be-whtfl.html |title=Fleurus (Municipality, Province of Hainaut, Belgium) |publisher=CRW Flags Inc. |access-date=2010-04-21}}</ref>\n\n[[Jean-Pierre Blanchard]] became the first person to ever fly a hot-air balloon in various countries, including the United States, the Netherlands, and Germany. His most notable flight crossed the [[English Channel]] heading to the [[Dover Castle]] accompanied by Dr. [[John Jeffries]], which occurred on 7 January 1785. In 1808, Blanchard fell from his balloon above The Hague and died. His wife continued his profession, but also died a decade later on a balloon, due to a firework festival causing the hydrogen in the balloon to be set on fire.<ref>{{Cite book |last=Winchester |first=Jim |title=A Chronology of Aviation |publisher=Amber Books |year=2007 |isbn=978-623-00-1136-8 |pages=8\u20139 |translator-last=Natalia |translator-first=Lucky |trans-title=Sebuah Kronologi Penerbangan |translator-last2=Dimitria |translator-first2=Ernest |translator-last3=Putra |translator-first3=Eddy}}</ref>\n\n [[File:Helsinki from air.jpg|thumb|A hot-air balloon over the city of [[Helsinki]] in September 2009]]\n[[File:Cappadociasunrise.jpg|thumb|Hot-air balloons, [[Cappadocia]] sunrise]]\n[[File:Cloudhoppers.jpg|right|thumb|A pair of [[Cloudhopper|Hopper balloons]]]]\n[[File:Bristol Balloon Fiesta 2009-20.JPG|right|thumb|[[Bristol International Balloon Fiesta]]]]\nModern hot-air balloons, with an onboard heat source, were developed by [[Ed Yost]], beginning during the 1950s; his work resulted in his first successful flight on October 22, 1960.<ref>{{cite news |url= https://www.nytimes.com/2007/06/04/us/04yost.html?_r=1&oref=slogin |title=Ed Yost, 87, Father of Modern Hot-Air Ballooning, Dies |access-date=2008-06-04 |work=The New York Times |first=Dennis |last=Hevesi |date=2007-06-04}}</ref> The first modern hot-air balloon to be made in the United Kingdom (UK) was the [[Bristol Belle]], built in 1967. Presently, hot-air balloons are used primarily for recreation.\n\n Hot-air balloons are able to fly to extremely high altitudes. On November 26, 2005 [[Vijaypat Singhania]] set the world altitude record for highest hot-air balloon flight, reaching {{convert|21027|m|ft|abbr=on}}. He took off from downtown [[Mumbai]], [[India]], and landed {{convert|240|km|mi|abbr=on}} south in Panchale.<ref>{{cite web |url=http://www.prdomain.com/upload/104/10443872.pdf |title=Dr. Vijaypat Singhania enters the Guinness World Records |access-date=2008-06-22 |archive-url=https://web.archive.org/web/20080624220610/http://www.prdomain.com/upload/104/10443872.pdf |archive-date=2008-06-24 |url-status=dead }}</ref> The previous record of {{convert|19811|m|ft|abbr=on}} had been set by [[Per Lindstrand]] on June 6, 1988, in [[Plano, Texas]].\n\nOn January 15, 1991, the ''Virgin Pacific Flyer'' balloon completed the longest flight in a hot-air balloon, when [[Per Lindstrand]] (born in Sweden, but resident in the UK) and [[Richard Branson]] of the UK flew {{convert|7671.91|km|abbr=on}} from Japan to Northern Canada. With a volume of 74,000 cubic meters (2.6 million cubic feet), the balloon envelope was the largest ever built for a hot-air craft. Designed to fly in the trans-oceanic [[jet stream]]s, the ''[[Pacific Flyer]]'' recorded the fastest ground speed for a manned balloon at {{convert|245|mph|km/h|order=flip|abbr=on}}. The longest duration record was set by Swiss psychiatrist [[Bertrand Piccard]] ([[Auguste Piccard]]'s grandson) and Briton Brian Jones, flying in the Breitling Orbiter 3. It was the first nonstop trip around the world by balloon. The balloon left Ch\u00e2teau-d'Oex, Switzerland, on March 1, 1999, and landed at 1:02 a.m. on March 21 in the Egyptian desert {{convert|300|mi|km|-2|order=flip|abbr=on}} south of Cairo. The two men exceeded distance, endurance, and time records, traveling 19 days, 21 hours, and 55 minutes. [[Steve Fossett]], flying solo, exceeded the record for briefest time traveling around the world on 3 July 2002 on his sixth attempt,<ref>{{cite web |url=https://www.theguardian.com/travel/2016/sep/16/experience-flew-solo-round-world-hot-air-balloon |title=Experience: I flew solo around the world in a hot-air balloon |newspaper=The Guardian |date=17 September 2016|author=Fedor Konyukhov |access-date= 17 September 2016}} Article by Konyukhov describing the experience.</ref> in 320 h 33 min.<ref name=record-ballooning>{{cite web |url=http://www.fai.org/record-ballooning |title=Balloon World Records |publisher=F\u00e9d\u00e9ration A\u00e9ronautique Internationale |access-date=17 September 2016 |url-status=dead |archive-url=https://web.archive.org/web/20160908172221/http://www.fai.org/record-ballooning |archive-date=8 September 2016 }} Steve Fossett and Fedor Konyukhov, both sub-class AM-15.</ref> [[Fedor Konyukhov#Ballooning|Fedor Konyukhov]] flew solo round the world on his first attempt in a hybrid hot-air/helium balloon from 11 to 23 July 2016<ref>{{cite web |url=https://www.fai.org/records?f%5B0%5D=field_record_sport%3A2027 |title=F\u00e9d\u00e9ration A\u00e9ronautique Internationale|website=F\u00e9d\u00e9ration A\u00e9ronautique Internationale|date= 20 June 2019 |access-date= 20 June 2019}}</ref> for a round-the world time of 268 h 20 min.<ref name=record-ballooning/>"}},
{"article_title": "Space suit", "pageid": "39375", "revid": "1060486876", "timestamp": "2021-12-15T20:51:38Z", "history_paths": [["Space suit --- Introduction ---"]], "categories": ["spacesuits", "rebreathers", "environmental suits", "human spaceflight", "spacecraft components", "space technology", "soviet inventions"], "heading_tree": {"Space suit --- Introduction ---": {"Requirements": {"Secondary requirements": {}, "Operating pressure": {}, "Physical effects of unprotected space exposure": {}}, "Design concepts": {"Soft suits": {}, "Hard-shell suits": {}, "Hybrid suits": {}, "Skintight suits": {}}, "Contributing technologies": {"Glove technology": {}, "Life support technology": {}, "Helmet technology": {}, "High-altitude suits": {}}, "List of space suit models": {"Soviet and Russian suit models": {}, "United States suit models": {"SpaceX suit (\"Starman suit\")": {}}, "Chinese suit models": {}}, "Emerging technologies": {"Additive manufacturing": {}, "Astronaut Glove Challenge": {}, "Aouda.X": {}, "Bio-Suit": {}, "Constellation Space Suit system": {}, "Final Frontier Design IVA Space Suit": {}, "I-Suit": {}, "Mark III": {}, "MX-2": {}, "North Dakota suit": {}, "PXS": {}, "Suitports": {}, "Z-series": {}}, "In fiction": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Space suit --- Introduction ---": "{{pp-semi|small=yes}}\n{{Distinguish|Single-person spacecraft}}\n{{Short description|Garment worn to keep a human alive in the harsh environment of outer space}}\n{{Use mdy dates|date=May 2012}}\n[[File:Aldrin Apollo 11 cropped.jpg|thumb|upright|[[Apollo/Skylab spacesuit|Apollo spacesuit]] worn by astronaut [[Buzz Aldrin]] on [[Apollo 11]]]]\n[[File:Iss009e29620.jpg|thumb|upright|[[Orlan space suit]] worn by astronaut [[Michael Fincke]] outside the [[International Space Station]]]]\n\nA '''space suit''' or '''spacesuit''' is a garment worn to keep a human alive in the harsh environment of [[outer space]], [[Vacuum (outer space)|vacuum]] and temperature extremes. Space suits are often worn inside [[spacecraft]] as a safety precaution in case of loss of cabin [[pressure]], and are necessary for [[extravehicular activity]] (EVA), work done outside spacecraft. Space suits have been worn for such work in Earth orbit, on the surface of the [[Moon]], and en route back to Earth from the Moon. Modern space suits augment the basic pressure garment with a complex system of equipment and environmental systems designed to keep the wearer comfortable, and to minimize the effort required to bend the limbs, resisting a soft pressure garment's natural tendency to stiffen against the vacuum. A self-contained [[oxygen]] supply and environmental control system is frequently employed to allow complete freedom of movement, independent of the spacecraft.\n\nThree types of space suits exist for different purposes: IVA (intravehicular activity), EVA (extravehicular activity), and IEVA (intra/extravehicular activity). IVA suits are meant to be worn inside a pressurized spacecraft, and are therefore lighter and more comfortable. IEVA suits are meant for use inside and outside the spacecraft, such as the [[Gemini space suit|Gemini G4C]] suit. They include more protection from the harsh conditions of space, such as protection from [[micrometeoroid]]s and extreme temperature change. EVA suits, such as the [[Extravehicular Mobility Unit|EMU]], are used outside spacecraft, for either planetary exploration or spacewalks. They must protect the wearer against all conditions of space, as well as provide mobility and functionality.<ref name=thomas/>\n\nSome of these requirements also apply to [[pressure suit]]s worn for other specialized tasks, such as high-altitude reconnaissance flight. At altitudes above the [[Armstrong limit]], around {{convert|19000|m|ft|abbr=on}}, water boils at body temperature and pressurized suits are needed.\n\nThe first full-pressure suits for use at extreme altitudes were designed by individual inventors as early as the 1930s. The first space suit worn by a human in space was the [[Soviet Union|Soviet]] [[SK-1 spacesuit|SK-1]] suit worn by [[Yuri Gagarin]] in 1961.\n\n [[File:STS-116 spacewalk 1.jpg|thumb|Space suits being used to work on the International Space Station.]]\n\nA space suit must perform several functions to allow its occupant to work safely and comfortably, inside or outside a spacecraft. It must provide:\n* A stable internal pressure. This can be less than Earth's atmosphere, as there is usually no need for the space suit to carry [[nitrogen]] (which comprises about 78% of Earth's atmosphere and is not used by the body). Lower pressure allows for greater mobility, but requires the suit occupant to breathe pure oxygen for a time before going into this lower pressure, to avoid [[decompression sickness]].\n* Mobility. Movement is typically opposed by the pressure of the suit; mobility is achieved by careful joint design. See the ''[[Space suit#Theories of design|Theories of space suit design]]'' section.\n* Supply of breathable oxygen and elimination of [[carbon dioxide]]; these gases are exchanged with the spacecraft or a [[Primary Life Support System|Portable Life Support System]] (PLSS)\n* Temperature regulation. Unlike on Earth, where heat can be transferred by [[convection]] to the atmosphere, in space, heat can be lost only by [[thermal radiation]] or by [[heat conduction|conduction]] to objects in physical contact with the exterior of the suit. Since the temperature on the outside of the suit varies greatly between sunlight and shadow, the suit is heavily insulated, and air temperature is maintained at a comfortable level.\n* A communication system, with external electrical connection to the spacecraft or PLSS\n* Means of collecting and containing solid and liquid bodily waste (such as a [[Maximum Absorbency Garment]])\n\n [[File:First Six Women Astronauts with Rescue Ball - GPN-2002-000207.jpg|thumb|From left to right, Margaret R. (Rhea) Seddon, Kathryn D. Sullivan, Judith A. Resnick, Sally K. Ride, Anna L. Fisher, and Shannon W. Lucid{{mdash}}The first six female astronauts of the United States stand with a [[Personal Rescue Enclosure]], a spherical life support ball for emergency transfer of people in space]]\nAdvanced suits better regulate the [[astronaut]]'s temperature with a [[Liquid Cooling and Ventilation Garment]] (LCVG) in contact with the astronaut's skin, from which the heat is dumped into space through an external radiator in the PLSS.\n\nAdditional requirements for EVA include:\n* Shielding against [[ultraviolet]] radiation\n* Limited shielding against [[particle radiation]]\n* Means to maneuver, dock, release, and tether onto a spacecraft\n* Protection against small [[micrometeoroid]]s, some traveling at up to 27,000 kilometers per hour, provided by a puncture-resistant [[Thermal Micrometeoroid Garment]], which is the outermost layer of the suit. Experience has shown the greatest chance of exposure occurs near the [[gravitational field]] of a moon or planet, so these were first employed on the [[Apollo program|Apollo]] lunar EVA suits (see ''[[Space suit#United States suit models|United States suit models]]'' below).\n\nAs part of [[astronautical hygiene]] control (i.e., protecting astronauts from extremes of temperature, radiation, etc.), a space suit is essential for extravehicular activity. The [[Apollo/Skylab A7L]] suit included eleven layers in all: an inner liner, a LCVG, a pressure bladder, a restraint layer, another liner, and a Thermal Micrometeoroid Garment consisting of five aluminized insulation layers and an external layer of white Ortho-Fabric. This space suit is capable of protecting the astronaut from temperatures ranging from {{convert|-156|\u00b0C}} to {{convert|121|\u00b0C}}.{{Citation needed|date=December 2010}}\n\nDuring exploration of the Moon or Mars, there will be the potential for lunar or Martian dust to be retained on the space suit. When the space suit is removed on return to the spacecraft, there will be the potential for the dust to contaminate surfaces and increase the risks of inhalation and skin exposure. Astronautical hygienists are testing materials with reduced dust retention times and the potential to control the dust exposure risks during planetary exploration. Novel ingress and egress approaches, such as [[suitport]]s, are being explored as well.\n\nIn [[NASA]] space suits, communications are provided via a cap worn over the head, which includes earphones and a microphone. Due to the coloration of the version used for Apollo and [[Skylab]], which resembled the coloration of the comic strip character [[Snoopy]], these caps became known as "[[Snoopy cap]]s".\n\n [[File:Prebreathe.jpg|thumb|Astronaut [[Steve MacLean (astronaut)|Steven G. MacLean]] pre-breathes prior to an EVA]]\nGenerally, to supply enough oxygen for [[Respiratory system|respiration]], a space suit using pure oxygen must have a pressure of about {{convert|32.4|kPa|Torr psi|sigfig=2|abbr=on}}, equal to the {{convert|20.7|kPa|Torr psi|sigfig=2|abbr=on}} [[partial pressure]] of oxygen in the [[Earth's atmosphere]] at sea level, plus {{convert|5.3|kPa|Torr psi|sigfig=2|abbr=on}} {{chem|CO|2}}{{citation needed|date=May 2020}} and {{convert|6.3|kPa|Torr psi|sigfig=2|abbr=on|lk=on}} [[water vapor]] pressure, both of which must be subtracted from the [[Pulmonary gas pressures|alveolar pressure]] to get alveolar oxygen partial pressure in 100% oxygen atmospheres, by the [[alveolar gas equation]].<ref>{{cite web |url=http://www.globalrph.com/martin_4_most2.htm |title=The Four Most Important Equations In Clinical Practice |last=Martin |first=Lawrence |website=GlobalRPh |publisher=David McAuley |access-date=June 19, 2013}}</ref> The latter two figures add to {{convert|11.6|kPa|Torr psi|sigfig=2|abbr=on}}, which is why many modern space suits do not use {{convert|20.7|kPa|Torr psi|sigfig=2|abbr=on}}, but {{convert|32.4|kPa|Torr psi|sigfig=2|abbr=on}} (this is a slight overcorrection, as alveolar partial pressures at sea level are slightly less than the former). In space suits that use 20.7 kPa, the astronaut gets only 20.7 kPa \u2212 11.6 kPa = {{convert|9.1|kPa|Torr psi|sigfig=2|abbr=on}} of oxygen, which is about the alveolar oxygen partial pressure attained at an altitude of {{convert|1860|m|ft|abbr=on}} above sea level. This is about 42% of normal partial pressure of oxygen at sea level, about the same as [[Cabin pressurization#Aircraft|pressure in a commercial passenger jet aircraft]], and is the realistic lower limit for safe ordinary space suit pressurization which allows reasonable capacity for work.\n\nWhen space suits below a specific operating pressure are used from craft that are pressurized to normal atmospheric pressure (such as the [[Space Shuttle]]), this requires astronauts to "pre-breathe" (meaning pre-breathe pure oxygen for a period) before donning their suits and depressurizing in the air lock. This procedure purges the body of dissolved nitrogen, so as to avoid decompression sickness due to rapid depressurization from a nitrogen-containing atmosphere.\n\n {{Main|Space exposure}}\n{{more citations needed section|date=December 2014}}\n\nThe human body can briefly survive the hard vacuum of space unprotected,<ref name="Bellows2006">{{cite web |url=http://www.damninteresting.com/outer-space-exposure |title=Outer Space Exposure |last=Bellows |first=Alan |date=November 27, 2006 |website=Damn Interesting |id=Article #237 |access-date=June 19, 2013}}</ref> despite contrary depictions in some popular [[science fiction]]. Human flesh expands to about twice its size in such conditions, giving the visual effect of a body builder rather than an overfilled balloon. Consciousness is retained for up to 15 seconds as the effects of [[Hypoxia (medical)|oxygen starvation]] set in. No snap freeze effect occurs because all heat must be lost through [[thermal radiation]] or the [[evaporation]] of liquids, and the blood does not boil because it remains pressurized within the body.\n\nIn space, there are many different highly energized [[subatomic particle|subatomic protons]] that will expose the body to extreme radiation. Although these compounds are minimal in amount, their high energy is liable to disrupt essential physical and chemical processes in the body, such as altering DNA or causing cancers. Exposure to radiation can create problems via two methods: the particles can react with water in the human body to produce [[free radicals]] that break DNA molecules apart, or by directly breaking the DNA molecules.<ref name=thomas>{{cite book|last1=Thomas|first1=Kenneth S.|last2=McMann|first2=Harold J.|title=U.S. Spacesuits|date=23 November 2011|publisher=Springer Science & Business Media}}</ref><ref>{{cite web|title=Space Radiation Analysis Group|url=http://srag.jsc.nasa.gov/Index.cfm|website=NASA, Johnson Space Center|publisher=NASA|access-date=16 February 2015|url-status=dead|archive-url=https://web.archive.org/web/20150218045538/http://srag.jsc.nasa.gov/Index.cfm|archive-date=February 18, 2015|df=mdy-all}}</ref>\n\nTemperature in space can vary extremely depending on where the Sun is. Temperatures from solar radiation can reach up to {{convert|250|\u00b0F}} and lower down to {{convert|-387|\u00b0F|0}}. Because of this, space suits must provide proper insulation and cooling.<ref name=thomas/>\n\nThe vacuum in space creates zero pressure, causing the gases and processes in the body to expand. In order to prevent chemical processes in the body from overreacting, it is necessary to develop a suit that counteracts against the pressure in space.<ref name=thomas/><ref>{{cite book|last1=Hanslmeier|first1=Arnold|title=The Sun and Space Weather|date=1 January 2002|publisher=Springer Science & Business Media|isbn=1402006845|pages=166\u201367|edition=Illustrated}}</ref> The greatest danger is in attempting to hold one's breath before exposure, as the subsequent [[Uncontrolled decompression#Explosive decompression|explosive decompression]] can damage the lungs. These effects have been confirmed through various accidents (including in very-high-altitude conditions, outer space and training [[vacuum chamber]]s).<ref name="Bellows2006" /><ref>{{cite web |url=http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html |title=Ask an Astrophysicist: Human Body in a Vacuum |website=Image the Universe! |publisher=[[NASA]] |access-date=December 14, 2008}}</ref> Human skin does not need to be protected from vacuum{{citation needed|date=May 2020}} and is gas-tight by itself. Instead, it only needs to be mechanically compressed to retain its normal shape. This can be accomplished with a tight-fitting elastic body suit and a [[helmet]] for containing [[breathing gas]]es, known as a [[space activity suit]] (SAS).\n\n {{Original research|section|date=February 2012}}\nA space suit should allow its user natural unencumbered movement. Nearly all designs try to maintain a constant volume no matter what movements the wearer makes. This is because [[Work (physics)|mechanical work]] is needed to change the volume of a constant pressure system. If flexing a joint reduces the volume of the space suit, then the astronaut must do extra work every time they bend that joint, and they have to maintain a force to keep the joint bent. Even if this force is very small, it can be seriously fatiguing to constantly fight against one's suit. It also makes delicate movements very difficult. The work required to bend a joint is dictated by the formula\n\n:<math>W=\\int_{V_i}^{V_f} \\,P\\,dV</math>\n\nwhere ''V<sub>i</sub>'' and ''V<sub>f</sub>'' are respectively the initial and final volume of the joint, ''P'' is the pressure in the suit, and ''W'' is the resultant work. It is generally true that all suits are more mobile at lower pressures. However, because a minimum internal pressure is dictated by life support requirements, the only means of further reducing work is to minimize the change in volume.\n\nAll space suit designs try to minimize or eliminate this problem. The most common solution is to form the suit out of multiple layers. The bladder layer is a rubbery, airtight layer much like a balloon. The restraint layer goes outside the bladder, and provides a specific shape for the suit. Since the bladder layer is larger than the restraint layer, the restraint takes all of the stresses caused by the pressure inside the suit. Since the bladder is not under pressure, it will not "pop" like a balloon, even if punctured. The restraint layer is shaped in such a way that bending a joint causes pockets of fabric, called "gores", to open up on the outside of the joint, while folds called "convolutes" fold up on the inside of the joint. The gores make up for the volume lost on the inside of the joint, and keep the suit at a nearly constant volume. However, once the gores are opened all the way, the joint cannot be bent any further without a considerable amount of work.\n\nIn some Russian space suits, strips of cloth were wrapped tightly around the [[astronaut#Russian|cosmonaut]]'s arms and legs outside the space suit to stop the space suit from ballooning when in space.{{citation needed|date=August 2017}}\n\nThe outermost layer of a space suit, the Thermal Micrometeoroid Garment, provides thermal insulation, protection from micrometeoroids, and shielding from harmful [[Sunlight|solar radiation]].\n\nThere are four main conceptual approaches to suit design:\n[[File:AX-5-spacesuit.jpg|thumb|NASA's experimental AX-5 hard-shell space suit (1988)]]\n\n Soft suits typically are made mostly of fabrics. All soft suits have some hard parts; some even have hard joint bearings. Intra-vehicular activity and early EVA suits were soft suits.\n\n Hard-shell suits are usually made of metal or composite materials and do not use fabric for joints. Hard suits joints use ball bearings and wedge-ring segments similar to an adjustable elbow of a stove pipe to allow a wide range of movement with the arms and legs. The joints maintain a constant volume of air internally and do not have any counter-force. Therefore, the astronaut does not need to exert to hold the suit in any position. Hard suits can also operate at higher pressures which would eliminate the need for an astronaut to pre-breathe oxygen to use a {{convert|34|kPa|psi|abbr=on}} space suit before an EVA from a {{convert|101|kPa|psi|abbr=on}} spacecraft cabin. The joints may get into a restricted or locked position requiring the astronaut to manipulate or program the joint. The NASA [[Ames Research Center]] experimental [[Powered exoskeleton#NASA AX-5 hard shell space suit|AX-5]] hard-shell space suit had a flexibility rating of 95%. The wearer could move into 95% of the positions they could without the suit on.\n\n Hybrid suits have hard-shell parts and fabric parts. NASA's [[Extravehicular Mobility Unit]] (EMU) uses a fiberglass [[Hard Upper Torso]] (HUT) and fabric limbs. [[ILC Dover]]'s [[I-Suit]] replaces the HUT with a fabric soft upper torso to save weight, restricting the use of hard components to the joint bearings, helmet, waist seal, and rear entry hatch. Virtually all workable space suit designs incorporate hard components, particularly at interfaces such as the waist seal, bearings, and in the case of rear-entry suits, the back hatch, where all-soft alternatives are not viable.\n\n {{details|Mechanical counterpressure suit}}\nSkintight suits, also known as mechanical counterpressure suits or space activity suits, are a proposed design which would use a heavy elastic body stocking to compress the body. The head is in a pressurized helmet, but the rest of the body is pressurized only by the elastic effect of the suit. This mitigates the constant volume problem,{{Citation needed|date=December 2017}} reduces the possibility of a space suit depressurization and gives a very lightweight suit. When not worn, the elastic garments may appear to be that of clothing for a small child. These suits may be very difficult to put on and face problems with providing a uniform pressure. Most proposals use the body's natural [[perspiration]] to keep cool. Sweat evaporates readily in vacuum and may [[deposition (phase transition)|desublime]] or deposit on objects nearby: optics, sensors, the astronaut's visor, and other surfaces.  The icy film and sweat residue may contaminate sensitive surfaces and affect optical performance.\n\n {{Expand section|date=October 2010}}\nRelated preceding technologies include the [[WWII gas mask|gas mask]] used in [[World War II]], the [[oxygen mask]] used by pilots of high-flying bombers in World War II, the high-altitude or vacuum suit required by pilots of the [[Lockheed U-2]] and [[Lockheed SR-71 Blackbird|SR-71 Blackbird]], the [[diving suit]], [[rebreather]], [[scuba diving]] gear, and many others.\n\nMany space suit designs are taken from the U.S. Air Force suits, which are designed to work in "high-altitude aircraft pressure[s]",<ref name=thomas/> such as the [[Navy Mark IV|Mercury IVA]] suit or the Gemini G4C, or the [[Advanced Crew Escape Suit]]s.<ref name=nasa>{{cite web|title=NASA Spacesuits|url=http://www.nasa.gov/externalflash/nasa_spacesuit/|website=NASA|publisher=NASA|access-date=17 February 2015|url-status=dead|archive-url=https://web.archive.org/web/20100520023431/http://www.nasa.gov/externalflash/nasa_spacesuit/|archive-date=May 20, 2010|df=mdy-all}}</ref>\n\n \nThe [[Navy Mark IV|Mercury IVA]], the first U.S. space suit design, included lights at the tips of the gloves in order to provide visual aid. As the need for extravehicular activity grew, suits such as the [[Apollo/Skylab A7L|Apollo A7L]] included gloves made of a metal fabric called Chromel-r in order to prevent punctures. In order to retain a better sense of touch for the astronauts, the fingertips of the gloves were made of silicone. With the shuttle program, it became necessary to be able to operate spacecraft modules, so the ACES suits featured gripping on the gloves. EMU gloves, which are used for spacewalks, are heated to keep the astronaut's hands warm. The Phase VI gloves, meant for use with the [[Mark III (space suit)|Mark III suit]], are the first gloves to be designed with "laser scanning technology, 3D computer modeling, stereo lithography, laser cutting technology and CNC machining".<ref group="NASA, ILC Dover Inc.">{{cite journal|last1=Graziosi|first1=David|last2=Stein|first2=James|last3=Ross|first3=Amy|last4=Kosmo|first4=Joseph|title=Phase VI Advanced EVA Glove Development and Certification for the International Space Station|date=21 January 2011}}</ref> This allows for cheaper, more accurate production, as well as increased detail in joint mobility and flexibility.\n\n \nPrior to the [[Apollo program|Apollo missions]], life support in space suits was connected to the space capsule via an umbilical cord-like device. However, with the Apollo missions, life support was configured into a removable capsule called the [[Primary Life Support System|Portable Life Support System]] that allowed the astronaut to explore the Moon without having to be attached to the space craft. The EMU space suit, used for spacewalks, allows the astronaut to manually control the internal environment of the suit. The Mark III suit has a backpack filled with about 12 pounds of liquid air, as well as pressurization and heat exchange.<ref name=nasa/>\n\n \nThe development of the spheroidal dome helmet was key in balancing the need for field of view, pressure compensation, and low weight. One inconvenience with some space suits is the head being fixed facing forwards and being unable to turn to look sideways. Astronauts call this effect "alligator head".\n\n [[File:Herreraspacesuit.jpg|thumb|Pressurised suit prototype designed by military engineer [[Emilio Herrera Linares|Emilio Herrera]] for a stratospheric balloon flight. c.1935]]\n* [[Evgeniy Chertovsky]] created his full-pressure suit or high-altitude "''skafandr''" (''\u0441\u043a\u0430\u0444\u0430\u043d\u0434\u0440'') in 1931. (\u0441\u043a\u0430\u0444\u0430\u043d\u0434\u0440 also means "[[Underwater diving|diving]] apparatus").\n* [[Emilio Herrera Linares|Emilio Herrera]] designed and built a full-pressure "[[stratonautical space suit]]" in 1935, which was to have been used during an open-basket balloon stratospheric flight scheduled for early 1936.<ref>{{cite encyclopedia |encyclopedia=Encyclopedia Astronautica |title=Escafandra Estratonautica |url=http://www.astronautix.com/craft/escutica.htm |access-date=June 19, 2013 |publisher=Mark Wade |url-status=dead |archive-url=https://web.archive.org/web/20130522143849/http://www.astronautix.com/craft/escutica.htm |archive-date=May 22, 2013 |df=mdy-all }}</ref>\n* [[Wiley Post]] experimented with a number of pressure suits for record-breaking flights.\n* [[Russell Colley]] created the space suits worn by the Project Mercury astronauts, including fitting [[Alan Shepard]] for his ride as America's first man in space on May 5, 1961.\n\n <span class="anchor" id="Models of historical significance"></span>\n\n * ''[[SK-1 spacesuit|SK series]] (CK)''{{Snd}}the spacesuit used for the [[Vostok program]] (1961\u20131963). Worn by [[Yuri Gagarin]] on the first crewed space flight.\n* No pressure suits were worn aboard [[Voskhod 1]].\n* ''[[Berkut spacesuit|Berkut]]'' (''\u0411\u0435\u0440\u043a\u0443\u0442'' meaning "[[golden eagle]]")''{{Snd}}''the spacesuit was a modified SK-1 used by the crew of [[Voskhod 2]] which included [[Alexei Leonov]] on the first [[spacewalk]] during (1965).\n* From [[Soyuz 1]] to [[Soyuz 11]] (1967\u20131971) no pressure suits were worn during [[Rocket launch|launch]] and [[Atmospheric entry|reentry]].{{Citation needed|date=June 2020}}\n* ''[[Yastreb]]'' (''\u042f\u0441\u0442\u0440\u0435\u0431'' meaning "[[hawk]]")''{{Snd}}''extravehicular activity spacesuit used during a crew exchange between [[Soyuz 4]] and [[Soyuz 5]] (1969).\n* [[Krechet-94]] (''\u041a\u0440\u0435\u0447\u0435\u0442'' meaning "[[gyrfalcon]]")''{{Snd}}''designed for the canceled Soviet crewed Moon landing.\n* [[Strizh]] (''\u0421\u0442\u0440\u0438\u0436'' meaning "[[swift (bird)]]")''{{Snd}}''developed for pilots of ''[[Buran programme|Buran]]''-class orbiters.\n* [[Sokol space suit|Sokol]] (''\u0421\u043e\u043a\u043e\u043b'' meaning "[[falcon]]")''{{Snd}}''suits worn by [[Soyuz spacecraft|Soyuz]] crew members during launch and reentry. They were first worn on [[Soyuz 12]]. They have been used from 1973 to present.\n* [[Orlan space suits|Orlan]] (''\u041e\u0440\u043b\u0430\u043d'' meaning "[[sea-eagle]]" or "[[bald eagle]]")''{{Snd}}''suits for extravehicular activity, originally developed for the Soviet lunar program as a lunar orbit EVA suit. It is Russia's current EVA suit. Used from 1977 to present.\n<gallery class="center" perrow="5">\nImage:Sk-1 spacesuit taken at the Memorial Museum of Space Exploration.jpg | SK-1 space suit\nImage:Berkut spacesuit.JPG |Berkut space suit\nImage:Yastreb suit.jpg | Yastreb space suit\nImage:Krechet space suit - Air and Space.jpg | Krechet space suit\nImage:Strizh spacesuit 4148047368 c19cec3782 o.jpg | Strizh space suit\nImage:Sokol KV2.JPG | [[Sokol space suit#Sokol-KV2|Sokol-KV2]] space suit\nImage:Orlan-MK-MAKS2009.jpg | Orlan-MK space suit\n</gallery>\n\n *In the early 1950s, [[Siegfried Hansen]] and colleagues at [[Litton Industries]] designed and built a working hard-shell suit, which was used inside vacuum chambers and was the predecessor of space suits used in NASA missions.<ref>{{cite news |title=Siegfried Hansen, Space Suit Father; Inventor Was 90 |work=[[The New York Times]] |url=https://www.nytimes.com/2002/07/24/us/siegfried-hansen-space-suit-father-inventor-was-90.html |date=July 24, 2002 |access-date=February 9, 2008}}</ref>\n*[[Navy Mark IV]] high-altitude/vacuum suit{{Snd}}used for [[Project Mercury]] (1961\u20131963).\n*[[Gemini space suit|Gemini]] space suits (1965\u20131966){{Snd}}there were three main variants developed: G3C designed for intra-vehicle use; G4C specially designed for EVA and intra-vehicle use; and a special G5C suit worn by the [[Gemini 7]] crew for 14 days inside the spacecraft.\n*[[Manned Orbiting Laboratory]] MH-7 space suits for the canceled MOL program.\n*[[Gemini space suit#Apollo program|Apollo Block I A1C]] suit (1966\u20131967){{Snd}}a derivative of the Gemini suit, worn by primary and backup crews in training for two early Apollo missions. The nylon pressure garment melted and burned through in the [[Apollo 1]] cabin fire. This suit became obsolete when crewed Block I Apollo flights were discontinued after the fire.\n*[[Apollo/Skylab A7L]] EVA and Moon suits{{Snd}}The Block II Apollo suit was the primary pressure suit worn for eleven Apollo flights, three Skylab flights, and the US astronauts on the [[Apollo\u2013Soyuz Test Project]] between 1968 and 1975. The pressure garment's nylon outer layer was replaced with fireproof [[Beta cloth]] after the Apollo 1 fire. This suit was the first to employ a liquid-cooled inner garment and outer micrometeroid garment. Beginning with the [[Apollo 13]] mission, it also introduced "commander's stripes" so that a pair of space walkers will not appear identical on camera.<ref>{{cite web\n | url =https://www.hq.nasa.gov/alsj/alsj-CDRStripes.html\n | title =Commander's Stripes\n | last =Jones\n | first =Eric\n | date =20 February 2006\n | website =Apollo Lunar Surface Journal\n | publisher =NASA\n | access-date =7 April 2019 }}</ref>\n*[[Shuttle Ejection Escape Suit]]{{Snd}}used from [[STS-1]] (1981) to [[STS-4]] (1982) by a two-man crew used in conjunction with the then-installed [[ejection seat]]s. Derived from a [[United States Air Force|USAF]] model.<ref>[[#Thomas & McMann|Thomas & McMann 2006]], pp. 38, 368</ref> These were removed once the Shuttle became certified.\n* From [[STS-5]] (1982) to [[STS-51-L]] (1986) no pressure suits were worn during launch and reentry. The crew would wear only a blue-[[flight suit]] with an oxygen helmet.\n*[[Launch Entry Suit]] first used on [[STS-26]] (1988), the first flight after the [[Space Shuttle Challenger disaster|''Challenger'' disaster]]. It was a partial pressure suit derived from a USAF model.<ref>[[#Thomas & McMann|Thomas & McMann 2006]]</ref> It was used from 1988 to 1998.\n*[[Advanced Crew Escape Suit]] used on the Space Shuttle starting in 1994.<ref>{{cite encyclopedia |encyclopedia=Encyclopedia Astronautica |title=ACES |url=http://www.astronautix.com/craft/aces.htm |access-date=June 19, 2013 |publisher=Mark Wade |url-status=dead |archive-url=https://web.archive.org/web/20130530174458/http://www.astronautix.com/craft/aces.htm |archive-date=May 30, 2013 |df=mdy-all }}</ref> The Advanced Crew Escape Suit or ACES suit, is a full-pressure suit worn by all Space Shuttle crews for the ascent and entry portions of flight. The suit is a direct descendant of the [[United States Air Force]] high-altitude pressure suits worn by SR-71 Blackbird and U-2 spy plane pilots, [[North American X-15]] and [[Project Gemini|Gemini]] pilot-astronauts, and the Launch Entry Suits worn by NASA astronauts starting on the STS-26 flight. It is derived from a USAF model.\n*[[Extravehicular Mobility Unit]] (EMU){{Snd}}used on both the Space Shuttle and [[International Space Station]] (ISS). The EMU is an independent anthropomorphic system that provides environmental protection, mobility, life support, and communications for a Space Shuttle or ISS crew member to perform an EVA in [[Earth orbit]]. Used from 1982 to present, but only available in limited sizing as of 2019.<ref>{{cite web |last1=Koren |first1=Marina |title=The Original Sin of NASA Space Suits |url=https://www.theatlantic.com/science/archive/2019/03/nasa-spacesuit-women-spacewalk/585805/ |website=TheAtlantic.com |publisher=The Atlantic Monthly Group |access-date=29 March 2019 |quote=In the 1990s, several years after the first American women flew to space, budget cuts forced NASA to trim its space-suit program...The limited sizing affected some astronaut duties.}}</ref>\n*Aerospace company [[SpaceX]] developed an IVA suit which is worn by astronauts involved in [[Commercial Crew Program]] missions operated by SpaceX since the [[Crew Dragon Demo-2|Demo-2]] mission (see [[#SpaceX suit ("Starman suit")]]).\n*Orion Crew Survival System (OCSS){{Snd}}will be used during launch and re-entry on the [[Orion (spacecraft)|Orion MPCV]]. It is derived from the Advanced Crew Escape Suit but is able to operate at a higher pressure and has improved mobility in the shoulders.<ref>{{cite web |author1=Shane E. Jacobs |author2=Donald B. Tufts |author3=Dustin M. Gohmert |title=Space Suit Development for Orion |url=https://ttu-ir.tdl.org/ttu-ir/bitstream/handle/2346/74166/ICES_2018_199.pdf |website=48th International Conference on Environmental Systems |access-date=6 July 2019 |location=Albuquerque, New Mexico |date=8-12 July 2018}}</ref>\n\n<gallery class="center" perrow="5">\nImage:Alan shepard.jpg | Mercury suit\nImage:G4C EVA 12 - cropped.jpg | Gemini G4C suit\nImage:MOL spacesuit.jpg | Manned Orbital Laboratory MH-7 space suit\nImage:Apollo 1 - Chaffee in Apollo Block I space suit.jpg | Apollo Block I A1C suit\nImage:Apollo 17 Cernan on moon cropped.jpg | Apollo/Skylab space suit\nImage:Shuttle Ejection Escape Suit John Young.jpg | Shuttle Ejection Escape Suit\nImage:STS 51-I emergency training - cropped.jpg | Shuttle Flight Suit\nImage:Launch entry suit.jpg | Launch Entry Suit\nImage:ACES STS-130.jpg | Advance Crew Escape Suit\nImage:STS-118 EVA EMU Suit.jpg| Extravehicular Mobility Unit\nImage:NASA astronaut Douglas Hurley suits up for launch on May 30, 2020.jpg|SpaceX IVA suit\n</gallery>\n\n In February 2015, [[SpaceX]] began developing a space suit for astronauts to wear within the [[SpaceX Dragon 2|Dragon 2]] space capsule.<ref name=sx20150227>\n{{cite web |last1=Reisman|first1=Garrett |title=Statement of Garrett Reisman before the Subcommittee on Space Committee on Science, Space, and Technology U.S. House Of Representatives |url=http://science.house.gov/sites/republicans.science.house.gov/files/documents/HHRG-114-SY16-WState-GReisman-20150227.pdf |website=science.house.gov |publisher=US House of Representatives publication of a SpaceX document provided to the committee |access-date=28 February 2015 |date=27 February 2015 |quote=Crew Dragon carries sufficient breathable gas stores to allow for a safe return to Earth in the event of a leak of up to an equivalent orifice of 0.25 inches in diameter. As an extra level of protection, the crew will wear SpaceX-designed space suits to protect them from a rapid cabin depressurization emergency event of even greater severity. The suits and the vehicle itself will be rated for operation at vacuum.}}</ref> Its appearance was jointly designed by Jose Fernandez\u2014a Hollywood [[costume designer]] known for his works for [[superhero film|superhero]] and [[science fiction film]]s\u2014and SpaceX founder and CEO [[Elon Musk]].<ref>{{Cite web|last=Martin|first=Guy|title=The Man Behind America's New Spacesuit: How Elon Musk Took Hollywood Costume Designer Jose Fernandez From Batman To NASA|url=https://www.forbes.com/sites/guymartin/2020/05/29/the-man-behind-americas-spiffy-new-spacesuit-how-hollywood-costume-designer-jose-fernandez-got-from-batman-and-daft-punk-to-nasa/|access-date=2020-06-03|website=Forbes|language=en}}</ref><ref>{{Cite web|last=Bobb|first=Brooke|title=SpaceX's New Suits Were Built for Superheroes, But What Would Wonder Woman Wear into Orbit?|url=https://www.vogue.com/article/spacex-space-suits-women-astronauts|access-date=2020-06-03|website=Vogue|language=en}}</ref> The first images of the suit were revealed in September 2017.<ref>{{cite news|last1=Etherington|first1=Darrell|title=Elon Musk shares first full-body photo of SpaceX's spacesuit|url=https://techcrunch.com/2017/09/08/elon-musk-shares-first-full-body-photo-of-spacexs-spacesuit/|access-date=6 February 2018|publisher=Tech Crunch|date=8 September 2017}}</ref> A mannequin, called "Starman" (after [[David Bowie]]'s [[Starman (song)|song of the same name]]), wore the SpaceX space suit during the [[Falcon Heavy test flight|maiden launch of the Falcon Heavy]] in February 2018.<ref>{{cite magazine|last1=Seemangal|first1=Robin|title=SPACEX SUCCESSFULLY LAUNCHES THE FALCON HEAVY\u2014AND ELON MUSK'S ROADSTER|url=https://www.wired.com/story/spacex-successfully-launches-the-falcon-heavyand-elon-musks-roadster/|access-date=6 February 2018|magazine=Wired|date=6 February 2018}}</ref><ref name=":2">{{Cite web|last=Brandon Specktor 08 February 2018|title=Starman's SpaceX Spacesuit Would Leave You Dead in Minutes|url=https://www.livescience.com/61705-starman-spacex-spacesuit.html|access-date=2020-06-03|website=livescience.com|language=en}}</ref> For this exhibition launch, the suit was not pressurized and carried no sensors.<ref>[https://motherboard.vice.com/en_us/article/3k7ngk/spacex-falcon-heavy-test-launch SpaceX Just Launched a Tesla Into Space on the Most Powerful Rocket in the World]. ''Motherboard''. 6 February 2018. Quote:"Musk said at a press conference after the launch that there were no sensors in the suit."</ref>\n\nThe suit, which is suitable for vacuum, offers protection against cabin depressurization through a single tether at the astronaut's thigh that feeds air and electronic connections.  The helmets, which are 3D-printed, contain microphones and speakers. As the suits need the tether connection and do not offer protection against radiation, they are not used for extra-vehicular activities.<ref>{{Cite web|last=May 2020|first=Elizabeth Howell 22|title=How SpaceX's sleek spacesuit changes astronaut fashion from the space shuttle era|url=https://www.space.com/spacex-crew-dragon-spacesuits-explained.html|access-date=2020-06-03|website=Space.com|language=en}}</ref>\n\nIn 2018, NASA commercial crew astronauts [[Bob Behnken]], and [[Doug Hurley]] tested the spacesuit inside the Dragon 2 spacecraft in order to familiarize themselves with the suit.<ref>{{cite web |last1=Kooser |first1=Amanda |title=NASA astronauts test SpaceX spacesuits in the Crew Dragon |url=https://www.cnet.com/news/nasa-astronauts-test-spacex-spacesuits-in-the-crew-dragon/ |website=cnet.com |access-date=November 9, 2018 |language=en |date=November 6, 2018}}</ref> They wore it in the [[Crew Dragon Demo-2]] flight launched on 30 May 2020.<ref name=":2" /> The suit is worn by astronauts involved in [[Commercial Crew Program]] missions involving SpaceX.\n\n * [[Shuguang (spacecraft)|Shuguang]] space suit: First generation EVA space suit developed by China for the 1967 canceled ''[[Shuguang (spacecraft)|Project 714]]'' crewed space program. It has a mass of about {{convert|10|kg|sigfig=1}}, has an orange colour, and is made of high-resistance multi-layer polyester fabric. The astronaut could use it inside the cabin and conduct an EVA as well.<ref>{{cite web|url=http://www.costind.gov.cn/n435777/n509091/n509092/24810.html|title=\u4e3a\u4e2d\u534e\u822a\u5929\u53f2\u518c\u518d\u6dfb\u8f89\u714c|publisher=\u56fd\u9632\u79d1\u5de5\u59d4\u65b0\u95fb\u5ba3\u4f20\u4e2d\u5fc3|date=November 14, 2005|access-date=July 22, 2008}}{{Dead link |date=June 2013}}</ref><ref>{{cite web |url=http://tech.tom.com/1121/1122/2005919-251558.html |title=\u822a\u5929\u670d\u5145\u538b\u5b9e\u9a8c |publisher=\u96f7\u9706\u4e07\u94a7 |date=September 19, 2005 |archive-url=https://web.archive.org/web/20051222024937/http://tech.tom.com/1121/1122/2005919-251558.html |archive-date=December 22, 2005 |access-date=July 24, 2008}}</ref><ref>{{cite web |url=http://tech.tom.com/1121/1122/2005916-250971.html |title=\u4e2d\u56fd\u6700\u65e9\u7814\u5236\u7684\u822a\u5929\u670d\u4e3a\u6854\u9ec4\u8272 \u91cd10\u5343\u514b |publisher=\u96f7\u9706\u4e07\u94a7 |date=September 16, 2005 |archive-url=https://web.archive.org/web/20051128053126/http://tech.tom.com/1121/1122/2005916-250971.html |archive-date=November 28, 2005 |access-date=July 24, 2008}}</ref>\n* '''[[Project 863]]'' space suit: Cancelled project of second generation Chinese EVA space suit.<ref>{{cite web|url=http://lib.buaa.edu.cn/buaa/detail_degreethesis.jsp?channelid=75044&record=8443|title=\u8231\u5916\u822a\u5929\u670d\u6db2\u51b7\u670d\u6563\u70ed\u7279\u6027\u7814\u7a76|publisher= \u5317\u4eac\u822a\u7a7a\u822a\u5929\u5927\u5b66\u56fe\u4e66\u9986|date=March 1, 2000|access-date=July 23, 2008}}{{Dead link |date=June 2013}}</ref>\n* [[Shenzhou IVA]] (\u795e\u821f) space suit: The suit was first worn by [[Yang Liwei]] on [[Shenzhou 5]], the first crewed Chinese space flight, it closely resembles a [[Sokol space suit#Sokol-KV2|Sokol-KV2]] suit, but it is believed to be a Chinese-made version rather than an actual Russian suit.<ref>{{cite news |title=Testimony of James Oberg: Senate Science, Technology, and Space Hearing: International Space Exploration Program |url=http://www.spaceref.com/news/viewsr.html?pid=12687 |work=SpaceRef |publisher=SpaceRef Interactive Inc. |location=Reston, VA |date=April 27, 2004 |access-date=April 12, 2011}}</ref><ref>[[#Seedhouse|Seedhouse 2010]], p. 180</ref> Pictures show that the suits on [[Shenzhou 6]] differ in detail from the earlier suit; they are also reported to be lighter.<ref>{{cite news |title=China Ramps Up Human Spaceflight Efforts |first=Tariq |last=Malik |url=http://www.space.com/488-china-ramps-human-spaceflight-efforts.html |work=[[Space.com]] |publisher=[[TechMediaNetwork, Inc.]] |date=November 8, 2004 |access-date=June 19, 2013}}</ref>\n* [[Orlan spacesuit|Haiying]] (\u6d77\u9e70\u53f7\u822a\u5929\u670d) EVA space suit: The imported Russian [[Orlan space suit#M model|Orlan-M]] EVA suit is called ''Haiying''. Used on [[Shenzhou 7]].\n* [[Feitian space suit|Feitian]] (\u98de\u5929\u53f7\u822a\u5929\u670d) EVA space suit: New generation indigenously developed Chinese-made EVA space suit also used for the Shenzhou 7 mission.<ref>{{cite web|url=http://news.sohu.com/20080722/n258298683.shtml|title=\u795e\u4e03\u51c6\u5907\u4e2d\u4fc4\u4ea7\u4e24\u5957\u822a\u5929\u670d \u51fa\u8231\u8005\u7a7f\u56fd\u4ea7\u822a\u5929\u670d|publisher= [[\u641c\u72d0]]|date=July 22, 2008|access-date=July 22, 2008}}{{Dead link|date=September 2010|bot=H3llBot}}</ref> The suit was designed for a spacewalk mission of up to seven hours.<ref>{{cite news |title=China's astronaut outfitters design material for spacewalk suits |editor-last=Xiao Jie |url=http://news.xinhuanet.com/english/2007-06/01/content_6182498.htm |work=English.news.cn |publisher=[[Xinhua News Agency]] |location=Beijing |date=June 1, 2007 |access-date=June 1, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20080125005254/http://news.xinhuanet.com/english/2007-06/01/content_6182498.htm |archive-date=January 25, 2008 |df=mdy-all }}</ref> Chinese astronauts have been training in the out-of-capsule space suits since July 2007, and movements are seriously restricted in the suits, with a mass of more than {{convert|110|kg}} each.<ref>{{cite news |url=http://english.peopledaily.com.cn/90001/90781/6218810.html |title=Chinese astronauts begin training for spacewalk |agency=Xinhua News Agency |work=[[People's Daily|People's Daily Online]] |publisher=[[Central Committee of the Communist Party of China]] |location=Beijing |date=July 18, 2007|access-date=August 1, 2007}}</ref>\n\n<gallery class="center" perrow="5">\nImage:Yang Liwei space suit.JPG | Shenzhou Intra-Vehicular Activity space suit\nImage:Chinese EVA spacesuit (1).JPG | Feitian space suit\n<!-- Image with inadequate rationale removed: Image:Nie Haisheng gets out of reentry.jpg | Shenzhou 6 space suit -->\n</gallery>\n\n {{update|section|inaccurate=y|date=April 2017}}\nSeveral companies and universities are developing technologies and prototypes which represent improvements over current space suits.\n\n [[3D printing]] (additive manufacturing) can be used to reduce the mass of hard-shell space suits while retaining the high mobility they provide. This fabrication method also allows for the potential for in-situ fabrication and repair of suits, a capability which is not currently available, but will likely be necessary for Martian exploration.<ref>{{cite conference |url=https://ttu-ir.tdl.org/handle/2346/73066 |title=In-Situ Fabricated Space Suits for Extended Exploration and Settlement |last1=Bartlett |first1=Harrison |last2=Bowser |first2=Joseph |last3=Callejon Hierro |first3=Carlos |last4=Garner |first4=Sarah |last5=Guloy |first5=Lawrence |last6=Hnatov |first6=Christina |last7=Kalman |first7=Jonathan |last8=Sosis |first8=Baram |last9=Akin |first9=David |date=July 16, 2017 |conference=2017 International Conference on Environmental Systems |conference-url=https://www.ices.space/ |location=Charleston, SC |access-date=December 11, 2018 }}</ref> The [[University of Maryland, College Park|University of Maryland]] began development of a prototype 3D printed hard suit in 2016, based on the kinematics of the [[Powered exoskeleton#NASA AX-5 hard shell space suit|AX-5]]. The prototype arm segment is designed to be evaluated in the [[Space Systems Laboratory (Maryland)|Space Systems Laboratory]] glovebox to compare mobility to traditional soft suits. Initial research has focused on the feasibility of printing rigid suit elements, bearing races, ball bearings, seals, and sealing surfaces.<ref>{{cite conference |url=https://ttu-ir.tdl.org/handle/2346/74196 |title=Developing Technologies and Techniques for Additive Manufacturing of Spacesuit Bearings and Seals |last1=Garner |first1=Sarah |last2=Carpenter |first2=Lemuel |last3=Akin |first3=David |date=July 8, 2018 |conference=2018 International Conference on Environmental Systems |conference-url=https://www.ices.space/ |location=Albuquerque, NM |access-date=December 11, 2018 }}</ref>\n\n There are certain difficulties in designing a dexterous space suit glove and there are limitations to the current designs. For this reason, the [[Centennial Challenges#Astronaut glove challenge|Centennial Astronaut Glove Challenge]] was created to build a better glove. Competitions have been held in 2007 and 2009, and another is planned. The 2009 contest required the glove to be covered with a micro-meteorite layer.\n\n [[File:Aouda.X space suit simulator.jpg|thumb|upright|Aouda.X]]\nSince 2009, the [[Austrian Space Forum]]<ref>{{cite web |url=http://www.oewf.org/cms/polares_suit.phtml |title=Spacesuit-simulator 'Aouda.X' |work=PolAres |publisher=[[Austrian Space Forum]] |access-date=June 19, 2013 |archive-url=https://web.archive.org/web/20130529104536/http://www.oewf.org/cms/polares_suit.phtml |archive-date=May 29, 2013 |url-status=dead }}</ref> has been developing "Aouda.X", an experimental Mars [[Human analog missions|analogue]] space suit focusing on an advanced [[human\u2013machine interface]] and on-board computing network to increase [[Situation awareness|situational awareness]]. The suit is designed to study contamination vectors in planetary exploration analogue environments and create limitations depending on the pressure regime chosen for a simulation.\n\nSince 2012, for the [[Austrian Space Forum#Mars2013 - Morocco Mars Simulation 2013|Mars2013 analogue mission]]<ref>{{cite web |url=http://www.oewf.org/cms/mars2013.phtml |title=Morocco 2013 Mars Analogue Field Simulation |work=PolAres |publisher=Austrian Space Forum |access-date=June 19, 2013}}</ref> by the Austrian Space Forum to [[Erfoud]], [[Morocco]], the Aouda.X analogue space suit has a sister in the form of Aouda.S.<ref>{{cite press release |title=Mars 2013 - Morocco Mars Analog Field Simulation |publisher=Austrian Space Forum |url=http://www.oewf.org/cms/mars-2013-press-information.phtml |access-date=June 19, 2013 |url-status=dead |archive-url=https://archive.today/20130624190103/http://www.oewf.org/cms/mars-2013-press-information.phtml |archive-date=June 24, 2013 |df=mdy-all }}</ref> This is a slightly less sophisticated suit meant primarily to assist Aouda.X operations and be able to study the interactions between two (analogue) astronauts in similar suits.\n\nThe Aouda.X and Aouda.S space suits have been named after the [[Aouda|fictional princess]] from the [[Jules Verne]]'s 1873 novel ''[[Around the World in Eighty Days]]''. A public display mock-up of Aouda.X (called Aouda.D) is currently on display at the Dachstein Ice Cave in [[Obertraun]], [[Austria]], after the experiments done there in 2012.<ref>{{cite web |url=http://blog.oewf.org/en/2012/08/aouda-d-ice-princess/ |title=Aouda.D, ice princess |work=PolAres |publisher=Austrian Space Forum |type=Blog |access-date=June 19, 2013}}</ref>\n\n [[Bio-Suit]] is a [[space activity suit]] under development at the [[Massachusetts Institute of Technology]], which {{as of|2006|lc=on}} consisted of several lower leg prototypes. Bio-suit is custom fit to each wearer, using laser body scanning.{{update after|2015|2|28}}\n\n On August 2, 2006, NASA indicated plans to issue a Request for Proposal (RFP) for the design, development, certification, production, and sustaining engineering of the [[Constellation Space Suit]] to meet the needs of the [[Constellation program|Constellation Program]].<ref>{{cite web |url=http://prod.nais.nasa.gov/cgi-bin/eps/synopsis.cgi?acqid=121486 |title=CONSTELLATION SPACE SUIT SYSTEM (CSSS), SOL NNJ06161022R |work=[[NASA Acquisition Internet Service]] |publisher=NASA |archive-url=https://web.archive.org/web/20090730021056/http://prod.nais.nasa.gov/cgi-bin/eps/synopsis.cgi?acqid=121486 |archive-date=July 30, 2009 |access-date=June 19, 2013}}</ref> NASA foresaw a single suit capable of supporting: survivability during launch, entry and abort; [[Weightlessness|zero-gravity]] EVA; lunar surface EVA; and Mars surface EVA.\n\nOn June 11, 2008, NASA awarded a US$745 million contract to [[Oceaneering International]] to create the new space suit.<ref>{{cite news |title=Get your first look at NASA's next spacesuit |url=http://www.nbcnews.com/id/25130313 |agency=Associated Press |work=[[NBCNews.com]] |date=June 12, 2008 |access-date=June 19, 2013}}</ref>\n\n \n[[File:FFD IVA Space Suit.jpg|thumb|upright|Final Frontier Design IVA Space Suit]]\n[[Final Frontier Design]] (FFD) is developing a commercial full IVA space suit, with their first suit completed in 2010.<ref>{{cite web |url=http://www.space.com/8774-inventors-unveil-private-spacesuit-york.html |title=Inventors to Unveil Private Spacesuit in New York |date=July 16, 2010 |access-date=July 17, 2010 }}</ref> FFD's suits are intended as a light-weight, highly mobile, and inexpensive commercial space suits. Since 2011, FFD has upgraded IVA suit's designs, hardware, processes, and capabilities. FFD has built a total of 7 IVA space suit (2016) assemblies for various institutions and customers since founding, and has conducted high fidelity human testing in simulators, aircraft, microgravity, and hypobaric chambers. FFD has a Space Act Agreement with NASA's Commercial Space Capabilities Office to develop and execute a Human Rating Plan for FFD IVA suit.<ref>{{cite web |url=https://www.nasa.gov/press/2014/december/nasa-selects-commercial-space-partners-for-collaborative-partnerships/#.VJmkYBGdA |title=NASA Selects Commercial Space Partners for Collaborative Partnerships |date=December 23, 2014 |access-date=December 24, 2010 }}</ref> FFD categorizes their IVA suits according to their mission: Terra for Earth-based testing, Stratos for high altitude flights, and Exos for orbital space flights. Each suit category has different requirements for manufacturing controls, validations, and materials, but are of a similar architecture.\n\n The [[I-Suit]] is a space suit prototype also constructed by ILC Dover, which incorporates several design improvements over the EMU, including a weight-saving soft upper torso. Both the Mark III and the I-Suit have taken part in NASA's annual [[Desert Research and Technology Studies]] (D-RATS) field trials, during which suit occupants interact with one another, and with rovers and other equipment.\n\n The [[Mark III (space suit)|Mark III]] is a NASA prototype, constructed by ILC Dover, which incorporates a hard lower torso section and a mix of soft and hard components. The Mark III is markedly more mobile than previous suits, despite its high operating pressure ({{convert|57|kPa|psi|abbr=on|disp=or}}), which makes it a "zero-prebreathe" suit, meaning that astronauts would be able to transition directly from a one-atmosphere, mixed-gas space station environment, such as that on the International Space Station, to the suit, without risking decompression sickness, which can occur with rapid depressurization from an atmosphere containing nitrogen or another inert gas.\n\n The MX-2 is a space suit analogue constructed at the [[University of Maryland, College Park|University of Maryland]]'s [[Space Systems Laboratory (Maryland)|Space Systems Laboratory]]. The MX-2 is used{{when|date=February 2015}} for crewed [[neutral buoyancy]] testing at the Space Systems Lab's Neutral Buoyancy Research Facility. By approximating the work envelope of a real EVA suit, without meeting the requirements of a flight-rated suit, the MX-2 provides an inexpensive platform for EVA research, compared to using EMU suits at facilities like NASA's [[Neutral Buoyancy Laboratory]].\n\nThe MX-2 has an operating pressure of 2.5\u20134 psi. It is a rear-entry suit, featuring a fiberglass [[Hard Upper Torso|HUT]]. Air, LCVG cooling water, and power are open loop systems, provided through an [[Umbilical cable|umbilical]]. The suit contains a [[Mac Mini]]{{Citation needed|date=June 2021}} computer to capture sensor data, such as suit pressure, inlet and outlet air temperatures, and heart rate.<ref>{{cite web |url=http://ssl.umd.edu/projects/MARSsuit/index.shtml |title=MARS Suit: MX-2 |website=[[Space Systems Laboratory (Maryland)|Space Systems Laboratory]] |publisher=[[University of Maryland, College Park|University of Maryland]] |location=College Park, MD |access-date=June 19, 2013 |archive-url=https://web.archive.org/web/20120903111105/http://ssl.umd.edu/projects/MARSsuit/index.shtml |archive-date=September 3, 2012 |url-status=dead |df=mdy-all }}</ref> Resizable suit elements and adjustable ballast allow the suit to accommodate subjects ranging in height from {{convert|68|to(-)|75|in|cm}}, and with a weight range of {{convert|120|lb|abbr=on}}.<ref>{{cite conference |url=http://www.sae.org/technical/papers/2006-01-2287 |title=System Overview and Operations of the MX-2 Neutral Buoyancy Space Suit Analogue |first1=Shane E. |last1=Jacobs |first2=David L. |last2=Akin |first3=Jeffrey R. |last3=Braden |date=July 17, 2006 |conference=International Conference On Environmental Systems |publisher=[[SAE International]] |id=2006-01-2287 |doi=10.4271/2006-01-2287 |access-date=June 12, 2007}}</ref>\n\n Beginning in May 2006, five [[North Dakota]] colleges collaborated on a new space suit prototype, funded by a US$100,000 grant from NASA, to demonstrate technologies which could be incorporated into a planetary suit. The suit was tested in the [[Theodore Roosevelt National Park]] [[badlands]] of western North Dakota. The suit has a mass of {{convert|47|lb}} without a life support backpack, and costs only a fraction of the standard US$12,000,000 cost for a flight-rated NASA space suit.<ref>{{cite web |url=http://www.howstuffworks.com/space-suit4.htm |title=How Space Suits Work |last=Freudenrich |first=Craig |website=[[HowStuffWorks]] |publisher=[[Discovery Communications]] |location=Atlanta, GA |access-date=June 19, 2013}}</ref>  The suit was developed in just over a year by students from the [[University of North Dakota]], [[North Dakota State University|North Dakota State]], [[Dickinson State University|Dickinson State]], the state [[North Dakota State College of Science|College of Science]] and [[Turtle Mountain Community College]].<ref>{{cite news |title=That's one small step toward Mars mission |first=James |last=MacPherson |url=http://www.signonsandiego.com/uniontrib/20060507/news_1n7suit.html |agency=[[Associated Press]] |work=[[U-T San Diego|The San Diego Union-Tribune]] |date=May 7, 2006 |access-date=June 19, 2013}}</ref> The mobility of the North Dakota suit can be attributed to its low operating pressure; while the North Dakota suit was field tested at a pressure of {{convert|1|psi|kPa Torr|abbr=on}} differential, NASA's EMU suit operates at a pressure of {{convert|4.7|psi|kPa Torr|abbr=on}}, a pressure designed to supply approximately sea-level oxygen partial pressure for [[Respiratory system|respiration]] (see discussion [[Space suit#Operating pressure|above]]).\n\n NASA's Prototype eXploration Suit (PXS), like the Z-series, is a rear-entry suit compatible with suitports.<ref name=":0">{{cite web |url=http://www.space.com/30360-the-martian-movie-nasa-mars-technology.html |title='The Martian' Shows 9 Ways NASA Tech Is Headed to Mars |last=Howell |first=Elizabeth |work=space.com |date=August 25, 2015 |access-date=December 18, 2015 }}</ref> The suit has components which could be 3D printed during missions to a range of specifications, to fit different individuals or changing mobility requirements.<ref name=":1">{{cite web |url=http://www.nasa.gov/feature/the-next-generation-of-suit-technologies |title=The Next Generation of Suit Technologies |publisher=NASA |date=October 1, 2015 |access-date=December 18, 2015 |archive-url=https://web.archive.org/web/20151215072049/http://www.nasa.gov/feature/the-next-generation-of-suit-technologies/ |archive-date=December 15, 2015 |url-status=dead }}</ref>\n\n A [[suitport]] is a theoretical alternative to an [[airlock]], designed for use in hazardous environments and in [[human spaceflight]], especially [[planet]]ary surface exploration. In a suitport system, a rear-entry space suit is attached and sealed against the outside of a spacecraft, such that an astronaut can enter and seal up the suit, then go on EVA, without the need for an airlock or depressurizing the spacecraft cabin. Suitports require less mass and volume than airlocks, provide [[dust]] mitigation, and prevent cross-contamination of the inside and outside environments. Patents for suitport designs were filed in 1996 by Philip Culbertson Jr. of NASA's Ames Research Center and in 2003 by Joerg Boettcher, Stephen Ransom, and Frank Steinsiek.<ref name = culbertson>{{cite web\n  | last = Culbertson\n  | first = Philip, Jr.\n  | title = Suitlock docking mechanism \u2013 United States Patent 5697108\n  | publisher = freepatentsonline.com\n  | date = September 30, 1996\n  | url = http://www.freepatentsonline.com/5697108.html\n  | access-date =June 15, 2006 }}</ref><ref>\n{{cite web\n  | last1 = Boettcher\n  | first1 = Joerg\n  | last2 =  Ransom\n  | first2 = Stephen\n  | last3 = Steinsiek\n  | first3 = Frank\n  | title =  Apparatus and method for putting on a protective suit \u2013 United States Patent 6959456\n  | publisher = freepatentsonline.com\n  | date = July 17, 2003\n  | url = http://www.freepatentsonline.com/6959456.html\n  | access-date =June 15, 2006 }}</ref>\n\n {{Main|Z series space suits}}\n[[File:Z-1 Spacesuit Prototype - standing Nov 2012.jpg|thumbnail|upright|right|Z-1 Series Suit]]\nIn 2012, NASA introduced the Z-1 space suit, the first in the Z-series of space suit prototypes designed by NASA specifically for planetary extravehicular activity. The Z-1 space suit includes an emphasis on mobility and protection for space missions. It features a soft torso versus the hard torsos seen in previous NASA EVA space suits, which provides reduced mass.<ref>{{cite web|last1=TIME Staff|title=NASA's Z-1 Space Suit|url=http://techland.time.com/2012/11/01/best-inventions-of-the-year-2012/slide/nasas-z-1-space-suit/|website=TIME|publisher=TIME Magazine|access-date=17 February 2015|url-status=dead|archive-url=https://web.archive.org/web/20150220013042/http://techland.time.com/2012/11/01/best-inventions-of-the-year-2012/slide/nasas-z-1-space-suit/|archive-date=February 20, 2015|df=mdy-all}}</ref> It has been labeled the "Buzz Lightyear suit" due to its green streaks for a design.\n\nIn 2014, NASA released the design for the Z-2 prototype, the next model in the Z-series. NASA conducted a poll asking the public to decide on a design for the Z-2 space suit. The designs, created by fashion students from Philadelphia University, were "Technology", "Trends in Society", and "Biomimicry".<ref>{{cite web|last1=Kirkpatrick|first1=Nick|title=Intergalactic fashion: NASA's next space suit|url=https://www.washingtonpost.com/news/morning-mix/wp/2014/04/15/intergalactic-fashion-nasas-next-space-suit/|work=[[The Washington Post]]|access-date=17 February 2015}}</ref> The design "Technology" won, and the prototype is built with technologies like [[3D printing]]. The Z-2 suit will also differ from the Z-1 suit in that the torso reverts to the hard shell, as seen in NASA's [[Extravehicular Mobility Unit|EMU]] suit.<ref>{{cite news|last1=CBC News|title=New Mars space suit unveiled by NASA|url=http://www.cbc.ca/news/technology/new-mars-space-suit-unveiled-by-nasa-1.2628383|access-date=17 February 2015|agency=CBC/Radio-Canada|date=1 May 2014}}</ref><ref>{{cite web|title=The NASA Z-2 Suit|url=http://jscfeatures.jsc.nasa.gov/z2/|website=NASA.gov|publisher=NASA|url-status=dead|archive-url=https://web.archive.org/web/20140329003404/http://jscfeatures.jsc.nasa.gov/z2/|archive-date=March 29, 2014|df=mdy-all}}</ref>\n\n {{main article|Spacesuits in fiction}}\nThe earliest space fiction ignored the problems of traveling through a vacuum, and launched its heroes through space without any special protection.  In the later 19th century, however, a more realistic brand of space fiction emerged, in which authors have tried to describe or depict the space suits worn by their characters.  These fictional suits vary in appearance and technology, and range from the highly authentic to the utterly improbable.\n\nA very early fictional account of space suits can be seen in [[Garrett P. Serviss]]' novel ''[[Edison's Conquest of Mars]]'' (1898).  Later comic book series such as [[Buck Rogers]] (1930s) and [[Dan Dare]] (1950s) also featured their own takes on space suit design. Science fiction authors such as [[Robert A. Heinlein]] contributed to the development of fictional space suit concepts.\n\n \n[[File:Teddies in Space.jpg|thumb|[[Teddy bears]] lifted to {{Convert|30085|m}} above sea level on a [[helium]] balloon in a materials experiment by [[CU Spaceflight]] and SPARKS science club. Each of the bears wore a different space suit designed by 11- to 13-year-olds from SPARKS.]]\n* [[Atmospheric diving suit]]\n* {{annotated link|Effect of spaceflight on the human body}}\n* {{annotated link|Extravehicular activity}}\n**By era:\n*** {{annotated link|List of spacewalks and moonwalks 1965\u20131999}}\n*** {{annotated link|List of spacewalks 2000\u20132014}}\n**By station:\n*** {{annotated link|List of Mir spacewalks}}\n*** {{annotated link|List of International Space Station spacewalks}}\n** {{annotated link|List of cumulative spacewalk records}}\n* {{annotated link|Manned Maneuvering Unit}}\n\n{{clear}}\n\n {{Reflist|30em}}\n{{reflist|group=NASA, ILC Dover Inc.}}\n\n {{Refbegin}}\n\n*{{cite book |last1=Abramov |first1=Isaac P. |last2=Skoog |first2=\u00c5. Ingemar |last3=Doodnik |first3=Mikhail N. |title=Russian Spacesuits |year=2003 |publisher=[[Springer Science+Business Media|Springer-Verlag]] |location=London; New York |isbn= 1-85233-732-X |oclc=51922847 |lccn=2003045585 |ref=Abramov & Skoog |display-authors=2}}\n*{{cite book|title=Spacesuit: Fashioning Apollo|first=Nicholas|last=de Monchaux|isbn=978-0262015202|publisher=MIT Press|year=2011}}\n*{{cite book |last=Kozloski |first=Lillian D. |title=U.S. Space Gear: Outfitting The Astronaut |url=https://archive.org/details/usspacegearoutfi0000kozl |url-access=registration |year=1994 |publisher=Smithsonian Institution Press |location=Washington, D.C. |isbn=0-87474-459-8 |oclc=623508754 |lccn=92-34611 |ref=Kozloski}}\n*{{cite book |last=Seedhouse |first=Erik |title=The New Space Race: China vs. the United States |year=2010 |publisher=Springer |location=Berlin; New York |isbn=978-1-4419-0879-7 |oclc=695700526 |lccn=2009936076 |ref=Seedhouse}}\n*{{cite book |last1=Thomas |first1=Kenneth S. |last2=McMann |first2=Harold J. |title=US Spacesuits |year=2006 |publisher=Springer-Verlag |location=Berlin; New York |isbn= 0-387-27919-9 |oclc=61477760 |lccn=2005929632 |ref=Thomas & McMann}}\n*{{cite book |last=Young |first=Amanda |others=Photographs by Mark Avino; introduction by Allan Needell; foreword by [[Thomas P. Stafford]] |title=Spacesuits: The Smithsonian National Air and Space Museum Collection |year=2009 |publisher=[[powerHouse Books]] |edition=1st |location=Brooklyn, NY |isbn=978-1-576-87498-1 |oclc=276334393 |lccn=2009075080 |ref=Young}}\n\n{{Refend}}\n\n {{Commons category|Space suits}}\n* [http://www.americanspacecraft.com/pages/spacesuit/index.html "Space suits"] at [http://www.americanspacecraft.com/pages/aaindex/home1.html A Field Guide to American Spacecraft]. A list compiled by Lee Sledge and James H. Gerard of American space suits and the museum locations where they are displayed.\n* [https://web.archive.org/web/20100828083207/http://www.astronautix.com/fam/spasuits.htm "Space Suits"] at [http://www.astronautix.com/index.html Encyclopedia Astronautica]. A complete listing of space suits.\n* [https://web.archive.org/web/20131207171721/http://www.zvezda-npp.ru/engl/index.html Russian space suits] at [[NPP Zvezda]]\n* [http://epizodsspace.airbase.ru/bibl/n_i_j/1978/6/skaf.html "Space suit" {{in lang|ru}}] [https://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http://epizodsspace.airbase.ru/bibl/n_i_j/1978/6/skaf.html&sl=ru&tl=en English] by G. Ilyin, Vladimir Ivanov, and Ivan Pavlov. Originally published by ''[[Nauka i Zhizn]]'', No. 6, 1978.\n* [https://web.archive.org/web/20050204193740/http://www.jsc.nasa.gov/history/hsf_history.htm "U.S. Human Spaceflight History"] at the [[Lyndon B. Johnson Space Center|Johnson Space Center]] See link near page end to ''Walking to Olympus: An EVA Chronology'' (PDF).\n* [https://web.archive.org/web/20010716093905/http://spaceboy.nasda.go.jp/note/yujin/e/yuj101_eva_e.html NASDA Online Space Notes] at the [[National Space Development Agency of Japan]] (NASDA) (2001)\n* [https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900001621_1990001621.pdf "Analysis of the Space Shuttle Extravehicular Mobility Unit \u2013 1986"] (PDF)\n* [https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19940017339_1994017339.pdf "NASA Space Shuttle EVA tools and equipment reference book \u2013 1993"] (PDF)\n* [https://history.nasa.gov/spacesuits.pdf "Space Suit Evolution From Custom Tailored to Off-the-Rack] (PDF)\n* [http://www.hq.nasa.gov/alsj/apollo.engin.html "Engineering Aspects of Apollo"] at the [http://www.hq.nasa.gov/alsj/ Apollo Lunar Surface Journal]. Section on the Apollo space suit and the Portable Life Support System.\n* [http://historicspacecraft.com/spacesuits.html "Space Suit Photos"] at [http://historicspacecraft.com/ Historic Spacecraft]\n* [http://www.nasa.gov/audience/foreducators/spacesuits/historygallery/ "Space suit and Spacewalk History Image Gallery"] at NASA\n* [https://web.archive.org/web/20110727010606/http://www.zvezda-npp.ru/histor.html Zvezda history {{in lang|ru}}] [https://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.zvezda-npp.ru%2Fhistor.html&sl=ru&tl=en English]\n* [https://www.ilcdover.com/aerospace/spacesuits/ "Spacesuits"] at [[ILC Dover]]\n* {{cite web |url=http://www.airspacemag.com/space-exploration/Space-Suits-Past-and-Future.html |title=Space Suits Past and Future |last=Klesius |first=Michael |date=June 10, 2009 |work=[[Air & Space/Smithsonian|AirSpaceMag.com]] |publisher=[[Smithsonian Institution]] |location=Washington, D.C. |access-date=June 20, 2013}}\n* In April 2011, the VOA [[Special English]] service of the [[Voice of America]] broadcast a 15-minute program on the evolution of space suits. A transcript and MP3 of the program, intended for English learners, can be found at [http://learningenglish.voanews.com/content/a-history-of-space-suits-119283494/113058.html "The Evolution of Spacesuits"].\n\n{{Spaceflight}}\n{{space suits|state=expanded}}\n{{Authority control}}\n\n{{DEFAULTSORT:Space Suit}}"}},
{"article_title": "Electroporation", "pageid": "39619", "revid": "1053639190", "timestamp": "2021-11-05T03:07:31Z", "history_paths": [["Electroporation --- Introduction ---", "History"]], "categories": ["biotechnology", "microbiology", "molecular biology", "gene delivery", "laboratory techniques"], "heading_tree": {"Electroporation --- Introduction ---": {"Laboratory practice": {}, "In vitro and animal studies": {}, "Medical applications": {"N-TIRE": {}, "Reversible electroporation": {}, "H-FIRE": {}, "Drug and gene delivery": {}}, "Physical mechanism": {"Gene electroporation": {}}, "History": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Electroporation --- Introduction ---|History": "In the 1960s it was known that by applying an external electric field, a large membrane potential at the two pole of a cell can be created. In the 1970s it was discovered  that when a membrane potential reached a critical level, the membrane would break down and that it could recover.<ref>{{Cite book|title=Guide to electroporation and electrofusion|date=1992|publisher=Academic Press|others=Chang, Donald C.|isbn=0121680401|location=San Diego|oclc=23868123}}</ref> By the 1980s, this opening was being used to introduce various materials/molecules into the cells.<ref name="neumann1982">{{cite journal | vauthors = Neumann E, Schaefer-Ridder M, Wang Y, Hofschneider PH | title = Gene transfer into mouse lyoma cells by electroporation in high electric fields | journal = The EMBO Journal | volume = 1 | issue = 7 | pages = 841\u20135 | date = 1982 | pmid = 6329708 | pmc = 553119 | doi = 10.1002/j.1460-2075.1982.tb01257.x}}</ref>"}},
{"article_title": "Variable Specific Impulse Magnetoplasma Rocket", "pageid": "40248", "revid": "1062247227", "timestamp": "2021-12-27T07:59:57Z", "history_paths": [["Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---"], ["Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---", "Research and development"], ["Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---", "Potential applications"]], "categories": ["emerging technologies", "magnetic propulsion devices", "plasma physics", "rocket propulsion", "ion engines"], "heading_tree": {"Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---": {"Design and operation": {"Advantages": {}, "Disadvantages": {}}, "Research and development": {"VX-10 to VX-50": {}, "VX-100": {}, "VX-200": {"VX-200SS": {}}}, "Potential applications": {"Mars in 39 days": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---": "{{short description|Electrothermal thruster in development}}\n{{Use mdy dates|date=February 2012}}\n[[File:Multi-megawatt VASIMR spacecraft.jpg|thumb|upright=1.5|Artist's impression of a multi-megawatt VASIMR spacecraft]]\nThe '''Variable Specific Impulse Magnetoplasma Rocket''' ('''VASIMR''') is an electrothermal thruster under development for possible use in [[spacecraft propulsion]]. It uses [[radio wave]]s to [[ionization|ionize]] and heat an [[chemically inert|inert]] [[rocket propellant|propellant]], forming a plasma, then a [[magnetic field]] to confine and accelerate the expanding [[Plasma (physics)|plasma]], generating [[thrust]]. It is a [[plasma propulsion engine]], one of several types of spacecraft [[Electrically powered spacecraft propulsion|electric propulsion]] systems.<ref name="VASIMR-Engine">{{cite web |url=http://www.adastrarocket.com/aarc/VASIMR |title=VASIMR |author=Ad Astra Rocket Company |publisher=Ad Astra Rocket Company |access-date=July 9, 2019 |archive-url=https://web.archive.org/web/20190707234837/http://www.adastrarocket.com/aarc/VASIMR |archive-date=July 7, 2019 |url-status=dead }}</ref>\n\nThe VASIMR method for heating [[plasma (physics)|plasma]] was originally developed during [[nuclear fusion]] research. VASIMR is intended to bridge the gap between high thrust, low [[specific impulse]] [[chemical rocket]]s and low thrust, high specific impulse electric propulsion, but has not yet demonstrated high thrust. The VASIMR concept originated in 1977 with former NASA astronaut [[Franklin Chang D\u00edaz]], who has been developing the technology ever since.<ref name="VASIMR-History">{{cite web |url=http://www.adastrarocket.com/aarc/history |title=History |author=Ad Astra Rocket Company |publisher=Ad Astra Rocket Company |access-date=July 9, 2019}}</ref>\n\n [[File:VASIMR system.jpg|thumb|upright=1.5|VASIMR schematic]]\nVASIMR is a type of electrothermal plasma thruster/electrothermal magnetoplasma thruster. In these engines, a neutral, inert propellant is ionized and heated using radio waves. The resulting plasma is then accelerated with magnetic fields to generate thrust. Other related [[electrically powered spacecraft propulsion]] concepts are the [[electrodeless plasma thruster]], the microwave [[arcjet rocket]], and the [[pulsed inductive thruster]]. \n\nThe propellant, a neutral gas such as [[argon]] or [[xenon]], is injected into a hollow cylinder surfaced with electromagnets. On entering the engine, the gas is first heated to a \u201ccold plasma\u201d by a helicon RF antenna/coupler that bombards the gas with electromagnetic energy, at a [[radio frequency|frequency]] of 10 to 50 [[megahertz|MHz]],<ref name="VASIMR Prefeasibility Analysis">{{Cite journal|url=|title=VASIMR Prefeasibility Analysis|journal=Advanced Propulsion Systems and Technologies, Today to 2020|volume=|page=335|date=2008|author=Alessandra Negrotti|bibcode=|doi=}}</ref> stripping electrons off the propellant atoms and producing a plasma of ions and free electrons. By varying the amount of RF heating energy and plasma, VASIMR is claimed to be capable of generating either low-thrust, high\u2013specific impulse exhaust or relatively high-thrust, low\u2013specific impulse exhaust.<ref name="Principal VASIMR results">{{Cite journal |url=http://www.adastrarocket.com/TimSTAIF2005.pdf |title=Principal VASIMR Results and Present Objectives |journal=Space Technology and Applications International Forum - Staif 2005 |volume=746 |pages=976\u2013982 |date=February 13\u201317, 2005 |author=Tim W. Glover |display-authors=etal |access-date=February 27, 2010 |bibcode=2005AIPC..746..976G |doi=10.1063/1.1867222 |archive-date=May 29, 2015 |archive-url=https://web.archive.org/web/20150529075638/http://www.adastrarocket.com/TimSTAIF2005.pdf |url-status=dead }}</ref> The second phase of the engine is a strong solenoid-configuration electromagnet that channels the ionized plasma, acting as a convergent-divergent nozzle like the physical nozzle in conventional rocket engines.\n\nA second coupler, known as the Ion Cyclotron Heating (ICH) section, emits electromagnetic waves in resonance with the orbits of ions and electrons as they travel through the engine. Resonance is achieved through a reduction of the magnetic field in this portion of the engine that slows the orbital motion of the plasma particles. This section further heats the plasma to greater than {{cvt|1000000|K|C F}} \u2014about 173 times the temperature of the [[Sun]]'s surface.<ref name="Air_March_2004">{{cite news|author=Beth Dickey|title=Star Power|url=http://www.airspacemag.com/space/star-power-6700758|access-date=February 7, 2014|newspaper=Air & Space, Smithsonian|date=March 2004}}</ref>\n\nThe path of ions and electrons through the engine approximates lines parallel to the engine walls; however, the particles actually orbit those lines while traveling linearly through the engine. The final, diverging, section of the engine contains an expanding magnetic field that ejects the ions and electrons from the engine at velocities as great as {{cvt|50000|m/s|km/h}}.<ref name="Principal VASIMR results"/><ref name="VASIMR-Technology">{{cite web |url=http://www.adastrarocket.com/aarc/Technology |title=Technology |date=2009 |author=Ad Astra Rocket Company |publisher=Ad Astra Rocket Company |access-date=December 10, 2012 |archive-date=May 22, 2013 |archive-url=https://web.archive.org/web/20130522003114/http://www.adastrarocket.com/aarc/Technology |url-status=dead }}</ref>\n\n In contrast to the typical [[cyclotron resonance]] heating processes, VASIMR ions are immediately ejected from the magnetic nozzle before they achieve [[Thermalisation|thermalized distribution]]. Based on novel theoretical work in 2004 by Alexey V. Arefiev and Boris N. Breizman of [[University of Texas at Austin]], virtually all of the energy in the ion [[cyclotron]] wave is uniformly transferred to ionized plasma in a single-pass cyclotron absorption process. This allows for ions to leave the magnetic nozzle with a very narrow energy distribution, and for significantly simplified and compact magnet arrangement in the engine.<ref name="Principal VASIMR results"/>\n\nVASIMR does not use electrodes; instead, it magnetically shields plasma from most hardware parts, thus eliminating electrode erosion, a major source of wear in ion engines.<ref name=Engine_2003>{{cite web|display-authors=7|author=Jared P. Squire|author2=Franklin R. Chang D\u00edaz|author3=Verlin T. Jacobson|author4=Tim W. Glover|author5=F. Wally Baity|author6=Richard H. Goulding|author7=Roger Bengtson|author8=Edgar A. Bering, III|author9=Kristy A. Stokke|name-list-style=amp|title=EXPERIMENTAL RESEARCH PROGRESS TOWARD THE VASIMR ENGINE|url=http://spaceflight.nasa.gov/shuttle/support/researching/aspl/reference/iepc03.pdf|website=28th International Electric Propulsion Conference, Toulouse, France, 17\u201321 March 2003|publisher=28th International Electric Propulsion Conference|access-date=February 7, 2014|archive-date=August 1, 2014|archive-url=https://web.archive.org/web/20140801011106/http://spaceflight.nasa.gov/shuttle/support/researching/aspl/reference/iepc03.pdf|url-status=dead}}</ref> Compared to traditional rocket engines with very complex plumbing, high performance valves, actuators and turbopumps, VASIMR has almost no moving parts (apart from minor ones, like gas valves), maximizing long term durability.{{citation_needed|date=July 2019}}\n\n According to Ad Astra as of 2015, the VX-200 engine requires 200 kW electrical power to produce {{Nowrap|5 N}} of thrust, or 40 kW/N.<ref name="VASIMR-Technology"/> In contrast, the conventional [[NEXT (ion thruster)|NEXT ion thruster]] produces 0.327 N with only 7.7 kW, or 24 kW/N.<ref name="VASIMR-Technology"/> Electrically speaking, NEXT is almost twice as efficient, and successfully completed a 48,000 hours (5.5 years) test in December 2009.<ref name=test>{{cite web| url=http://www.nasa.gov/home/hqnews/2013/jun/HQ_13-193_Ion_Thruster_Record.html | title= NASA Thruster Achieves World-Record 5+ Years of Operation | author=Dwayne Brown | author2=Katherine K. Martin | author3= Glenn Mahone |access-date=2013-06-24}}</ref><ref>{{cite web| url=http://www.nasa.gov/content/next-provides-lasting-propulsion-and-high-speeds-for-deep-space-missions/index.html | title= NEXT Provides Lasting Propulsion and High Speeds for Deep Space Missions | author= Nancy Smith Kilkenny, SGT, Inc. |access-date=29 September 2013}}</ref>\n\nNew problems also emerge with VASIMR, such as interaction with strong magnetic fields and thermal management. The inefficiency with which VASIMR operates generates substantial [[waste heat]] that needs to be channeled away without creating thermal overload and thermal stress. The [[superconducting magnet|superconducting electromagnets]] necessary to contain hot plasma generate [[Tesla (unit)|tesla]]-range magnetic fields<ref name="VASIMR Exceeding 50kW">{{cite web |url=http://www.adastrarocket.com/ISGLP_JPSquire2008.pdf |title=VASIMR Performance Measurements at Powers Exceeding 50 kW and Lunar Robotic Mission Applications |date=September 5\u20136, 2008 |author=Jared P. Squire |display-authors=etal |publisher=International Interdisciplinary Symposium on Gaseous and Liquid Plasmas |access-date=February 27, 2010 |archive-date=February 26, 2015 |archive-url=https://web.archive.org/web/20150226072105/http://www.adastrarocket.com/ISGLP_JPSquire2008.pdf |url-status=dead }}</ref> that can cause problems with other onboard devices and produce unwanted torque by interaction with the [[magnetosphere]]. To counter this latter effect, two thruster units can be packaged with magnetic fields oriented in opposite directions, making a net zero-torque magnetic [[quadrupole]].<ref name="aarc20110208">{{cite web |title=International Space Station Mission |url=http://www.adastrarocket.com/aarc/VASIMRISS |publisher=Ad Astra Rocket Company |access-date=February 8, 2011 |date=2011 |quote=The VX-200 will provide the critical data set to build the VF-200-1, the first flight unit, to be tested in space aboard the International Space Station (ISS). The electrical energy will come from ISS at low power level, be stored in batteries and used to fire the engine at 200 kW. |url-status=dead |archive-url=https://web.archive.org/web/20110315070521/http://www.adastrarocket.com/aarc/VASIMRISS |archive-date=March 15, 2011 |df=mdy-all }}</ref>\n\nThe required power generation technology for fast interplanetary travel does not currently exist and is not feasible with current state-of-the-art technology.<ref name=pressrelease2011>{{Cite web |url=http://www.adastrarocket.com/VASIMR_development_AdAstra_15July2011.pdf |date=July 15, 2011 |title=Facts About the VASIMR\u00ae Engine and its Development |publisher=Ad Astra Rocket Company |access-date=May 23, 2012 |archive-date=May 16, 2012 |archive-url=https://web.archive.org/web/20120516194823/http://www.adastrarocket.com/VASIMR_development_AdAstra_15July2011.pdf |url-status=dead }}</ref>\n\n The first VASIMR experiment was conducted at [[Massachusetts Institute of Technology]] in 1983. Important refinements were introduced in the 1990s, including the use of the helicon plasma source, which replaced the plasma gun originally envisioned and its electrodes, adding to durability and long life.{{citation_needed|date=June 2019}}\n\nAs of 2010, [[Ad Astra Rocket Company]] (AARC) was responsible for VASIMR development, signing the first [[Space Act Agreement]] on 23 June 2005 to privatize VASIMR technology. [[Franklin Chang D\u00edaz]] is Ad Astra's chairman and CEO, and the company had a testing facility in [[Liberia, Costa Rica]] on the campus of [[EARTH University|Earth University]].<ref name="summary">{{cite web |url=http://www.adastrarocket.com/EXECUTIVE%20SUMMARY240110.pdf |title=Executive summary |date=January 24, 2010 |publisher=Ad Astra Rocket Company |access-date=February 27, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100331171616/http://www.adastrarocket.com/EXECUTIVE%20SUMMARY240110.pdf |archive-date=March 31, 2010 |df=mdy-all }}</ref>\n\n In 1998, the first helicon plasma experiment was performed at the [[Johnson Space Center#Advanced Space Propulsion Laboratory|ASPL]]. VASIMR experiment 10 (VX-10) in 1998 achieved a helicon RF plasma discharge of up to 10 kW and VX-25 in 2002 of up to 25 kW. By 2005 progress at ASPL included full and efficient plasma production and acceleration of the plasma ions with the 50 kW, {{convert|0.5|N|lbf|1}} thrust VX-50.<ref name="Principal VASIMR results"/> Published data on the 50 kW VX-50 showed the electrical efficiency to be 59% based on a 90% coupling efficiency and a 65% ion speed boosting efficiency.<ref name="IEPC-2007-181">{{cite web |url=http://www.adastrarocket.com/Jared_IEPC07.pdf |title=High Power VASIMR Experiments using Deuterium, Neon and Argon |date=September 17\u201320, 2007 |first1=Jared P |last1=Squire |display-authors=etal |publisher=International Electric Propulsion Conference 2007 |access-date=February 27, 2010 |archive-date=February 26, 2015 |archive-url=https://web.archive.org/web/20150226072114/http://www.adastrarocket.com/Jared_IEPC07.pdf |url-status=dead }}</ref>{{failed verification|date=April 2021}}\n\n The 100 kilowatt VASIMR experiment was successfully running by 2007 and demonstrated efficient plasma production with an ionization cost below 100{{nbsp}}eV.<ref name=PR_June_2007>{{cite web|title=Ad Astra's VX-100 test bed achieves record plasma performance|url=http://www.adastrarocket.com/AdAstraPressRelease061207-1.pdf|website=PRESS RELEASE 061207, June 12, 2007|publisher=Ad Astra|access-date=February 7, 2014|archive-date=October 30, 2012|archive-url=https://web.archive.org/web/20121030190312/http://www.adastrarocket.com/AdAstraPressRelease061207-1.pdf|url-status=dead}}</ref> VX-100 plasma output tripled the prior record of the VX-50.<ref name=PR_June_2007/>\n\nThe VX-100 was expected to have an ion speed boosting efficiency of 80%, but could not achieve this efficiency due to losses from the conversion of DC electric current to radio frequency power and the auxiliary equipment for the superconducting magnet.<ref name="IEPC-2007-181"/><ref name="whitepaper">{{cite web |url=http://www.adastrarocket.com/AIAA2006.pdf |title=Recent Improvements In Ionization Costs And Ion Cyclotron Heating Efficiency In The VASIMR Engine |date=January 9\u201312, 2006 |first1=Edgar A |last1=Bering |display-authors=etal |publisher=AIAA Aerospace Sciences Meeting and Exhibit |access-date=February 27, 2010 |archive-date=January 19, 2016 |archive-url=https://web.archive.org/web/20160119120839/http://www.adastrarocket.com/AIAA2006.pdf |url-status=dead }}</ref> In contrast, 2009 state-of-the-art, proven ion engine designs such as NASA's [[High Power Electric Propulsion]] (HiPEP) operated at 80% total thruster/[[power processing unit|PPU]] energy efficiency.<ref name="NASA report">{{cite web |url=ftp://ftp.grc.nasa.gov/users/ep/ion/publications/2004/onsite/aiaa-2004-3453.pdf |title=An Overview of the High Power Electric Propulsion (HiPEP) Project |date=July 11\u201314, 2004 |first1=Frederick W |last1=Elliott |display-authors=etal |publisher=AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit |access-date=February 27, 2010 }}{{dead link|date=January 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>\n\n [[File:VX-200 operation full power.jpg|thumb|upright=1.5|VX-200 plasma engine at full power, employing both stages with full magnetic field]]\nOn 24 October 2008, the company announced in a press release that the [[Helicon (physics)|helicon]] plasma generation component of the 200 kW VX-200 engine had reached operational status. The key enabling technology, solid-state DC-RF power-processing, reached 98% efficiency. The helicon discharge used 30 kW of radio waves to turn [[argon]] gas into plasma. The remaining 170 kW of power was allocated for acceleration of plasma in the second part of the engine, via ion cyclotron resonance heating.<ref name="VASIMR VX-200 first stage">{{cite press release |url=http://www.adastrarocket.com/Release241008.pdf |title=VASIMR VX-200 first stage achieves full power rating |publisher=Ad Astra Rocket Company |date=October 24, 2008 |access-date=February 27, 2010 |archive-date=November 5, 2015 |archive-url=https://web.archive.org/web/20151105185042/http://www.adastrarocket.com/Release241008.pdf |url-status=dead }}</ref>\n\nBased on data from VX-100 testing,<ref name="VASIMR Exceeding 50kW"/> it was expected that, if room temperature superconductors are ever discovered, the VX-200 engine would have a system efficiency of 60\u201365% and a potential thrust level of 5 N. Optimal [[specific impulse]] appeared to be around 5,000 s using low cost argon propellant. One of the remaining untested issues was whether the hot plasma actually detached from the rocket. Another issue was waste heat management. About 60% of input energy became useful kinetic energy. Much of the remaining 40% is secondary ionizations from plasma crossing magnetic field lines and exhaust divergence. A significant portion of that 40% was waste heat (see [[energy conversion efficiency]]). Managing and rejecting that waste heat is critical.<ref>{{cite journal |title=A review of the processing, composition, and temperature-dependent mechanical and thermal properties of dielectric technical ceramics |journal=Journal of Materials Science |volume = 47|issue=10 |pages=4211\u20134235 |first1=Daith\u00ed |last1=de Faoite |first2=David J |last2=Browne |first3=Franklin R |last3=Chang-D\u00edaz |first4=Kenneth T |last4=Stanton |date=November 17, 2011 |doi=10.1007/s10853-011-6140-1|bibcode = 2012JMatS..47.4211F |hdl=10197/8477 |hdl-access=free }}</ref>\n\nBetween April and September 2009, 200 kW tests were performed on the VX-200 prototype with 2 [[tesla (unit)|tesla]] superconducting magnets that are powered separately and not accounted for in any "efficiency" calculations.<ref>{{cite press release |url=http://www.adastrarocket.com/Release_200kW_01Oct2009Final.pdf |title=VASIMR VX-200 reaches 200 kW power milestone |publisher=Ad Astra Rocket Company |date=September 30, 2011 |access-date=February 24, 2012 |archive-date=March 1, 2012 |archive-url=https://web.archive.org/web/20120301192252/http://www.adastrarocket.com/Release_200kW_01Oct2009Final.pdf |url-status=dead }}</ref> During November 2010, long duration, full power firing tests were performed, reaching steady state operation for 25 seconds and validating basic design characteristics.<ref name="VASIMR VX-200 firing for 25 seconds">{{cite web |url=https://www.youtube.com/watch?v=BRS26DcQhq0  |archive-url=https://ghostarchive.org/varchive/youtube/20211211/BRS26DcQhq0| archive-date=2021-12-11 |url-status=live|title=Video of VASIMR VX-200 firing for 25 seconds at full power rating |date=December 15, 2010 |author=Benwl |publisher=Ad Astra Rocket Company |access-date=January 4, 2011}}{{cbignore}}</ref>\n\nResults presented in January 2011 confirmed that the design point for optimal efficiency on the VX-200 is 50 km/s exhaust velocity, or an [[specific impulse|''I''{{sub|sp}}]] of 5000{{nbsp}}s. The 200 kW VX-200 had executed more than 10,000 engine firings with [[argon]] propellant at full power by 2013, demonstrating greater than 70% thruster efficiency relative to RF power input.<ref name=ilin2013>{{cite conference |url=http://www.adastrarocket.com/AndrewIEPC13-336-Paper.pdf |title=VASIMR Solar Powered Missions for NEA Retrieval and NEA Deflection |conference=33rd International Electric Propulsion Conference. October 6\u201310, 2013. Washington, D.C. |first1=Andrew V. |last1=Ilin |first2=Daniel A. |last2=Gilman |first3=Mark D. |last3=Carter |first4=Franklin R. |last4=Chang D\u00edaz |first5=Jared P. |last5=Squire |first6=Joseph E. |last6=Farrias |date=2013 |id=IEPC-2013-336 |access-date=May 14, 2014 |archive-date=May 14, 2014 |archive-url=https://web.archive.org/web/20140514181304/http://www.adastrarocket.com/AndrewIEPC13-336-Paper.pdf |url-status=dead }}</ref>\n\n In March 2015, Ad Astra announced a $10 million award from NASA to advance the technology readiness of the next version of the VASIMR engine, the '''VX-200SS''' to meet the needs of deep space missions.<ref>{{cite press release |url=https://www.nasa.gov/press/2015/march/nasa-announces-new-partnerships-with-us-industry-for-key-deep-space-capabilities/ |title=NASA Announces New Partnerships with U.S. Industry for Key Deep-Space Capabilities |publisher=NASA |date=March 30, 2015 |access-date=July 24, 2021}}</ref> The SS in the name stands for "steady state", as a goal of the long duration test is to demonstrate continuous operation at thermal steady state.<ref>{{cite press release |url=https://adastrarocket.com/AdAstraRelease033115final.pdf |title=Ad Astra Rocket Company wins major NASA advanced propulsion contract |publisher=Ad Astra Rocket Company |date=March 31, 2015 |access-date=July 24, 2021 |archive-date=July 24, 2021 |archive-url=https://web.archive.org/web/20210724083602/https://adastrarocket.com/AdAstraRelease033115final.pdf |url-status=dead }}</ref>\n\nIn August 2016, Ad Astra announced completion of the milestones for the first year of its 3-year contract with NASA. This allowed for first high-power plasma firings of the engines, with a stated goal to reach 100{{nbsp}}hr and 100 kW by mid-2018.<ref>{{cite press release |url=https://adastrarocket.com/pressReleases/AdAstra-Release-080316-final.pdf |title=Ad Astra Rocket Company successfully completes all NASA NextStep Contract Milestones for year one, receives NASA approval to proceed with year two |publisher=Ad Astra Rocket Company |date=August 3, 2016 |access-date=July 24, 2021}}</ref> In August 2017, the company reported completing its Year 2 milestones for the VASIMR electric plasma rocket engine. NASA gave approval for Ad Astra to proceed with Year 3 after reviewing completion of a 10-hour cumulative test of the VX-200SS engine at 100{{nbsp}}kW. It appears as though the planned 200 kW design is being run at 100 kW for reasons that are not mentioned in the press release.<ref name="Ad_Astra_20170809">{{cite press release |url=https://adastrarocket.com/pressReleases/AdAstraRelease080917-final.pdf |title=Ad Astra Rocket Company successfully completes all NASA NextStep Contract Milestones for year two, receives NASA approval to proceed with year three |publisher=Ad Astra Rocket Company |date=August 9, 2017 |access-date=August 9, 2017}}</ref> \n\t \nIn August 2019, Ad Astra announced the successful completion of tests of a new generation radio-frequency ([[RF]]) Power Processing Unit (PPU) for the VASIMR engine, built by [[Aethera Technologies]] Ltd. of Canada.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2019/20190820-AdAstra-Aethera.pdf |title=Aethera's New RF Power Processing Unit for the VASIMR Engine Successfully Completes Full Power Vacuum and Magnetic Field Tests at Ad Astra Rocket Company's Texas Facility |publisher=Ad Astra Rocket Company |date=August 20, 2019 |access-date=July 24, 2021}}</ref> Ad Astra declared a power of 120 [[kW]] and >97% electrical-to-RF power efficiency, and that, at 52 kg, the new RF PPU is about 10x lighter than the PPUs of competing electric thrusters (power-to-weight ratio: 2.31 kW/kg)\n\nIn July 2021, Ad Astra announced the completion of a record-breaking test for the engine, running it for 28 hours at a power level of 82.5{{nbsp}}kW.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2021/20210709-PressRelease.pdf |title=Ad Astra Rocket Company shatters power and endurance record in recent tests of the VASIMR VX-200SS plasma rocket |publisher=Ad Astra Rocket Company |date=July 9, 2021 |access-date=July 15, 2021}}</ref> A second test, conducted from July 12 to 16, successfully ran the engine for 88 hours at a power level of 80{{nbsp}}kW.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2021/20210722-PressRelease.pdf |title=VASIMR VX-200SS plasma rocket completes record 88-hour high power endurance test |publisher=Ad Astra Rocket Company |date=July 22, 2021 |access-date=July 24, 2021}}</ref> Ad Astra anticipates conducting 100{{nbsp}}kW power level tests in the second half of 2021.\n\n VASIMR has a comparatively poor thrust-to-weight ratio, and requires an ambient vacuum.\n\nProposed applications for VASIMR such as the rapid transportation of people to Mars would require a very high power, low mass energy source, ten times more efficient than a nuclear reactor (see [[nuclear electric rocket]]). In 2010 NASA Administrator [[Charles Bolden]] said that VASIMR technology could be the breakthrough technology that would reduce the travel time on a Mars mission from 2.5 years to 5 months.<ref name='Morring'>{{cite journal|last1=Morring |first1=Frank |date=2010 |title=Commercial Route |journal=Aviation Week & Space Technology |volume=172 |issue=6 |pages=20\u201323 }}</ref> However this claim has not been repeated in the last decade.\n\nIn August 2008, Tim Glover, Ad Astra director of development, publicly stated that the first expected application of VASIMR engine is "hauling things [non-human cargo] from low-Earth orbit to low-lunar orbit" supporting NASA's return to Moon efforts.<ref name="Discovery News">{{cite web |url=http://dsc.discovery.com/news/2008/08/07/plasma-rocket.html |title=Plasma Rocket May Be Tested at Space Station |date=August 7, 2008 |author=Irene Klotz |publisher=Discovery News |access-date=February 27, 2010 }}</ref>\n\n In order to conduct an imagined crewed trip to Mars in 39 days,<ref>Video: "[https://www.youtube.com/watch?v=-nyepvfuHho Mars in 39 Days?: the VASIMR Plasma Engine. Franklin Chang-Diaz, Ph.D.]"</ref> the VASIMR would require an electrical power level far beyond anything currently possible or predicted.\n\nOn top of that, any power generation technology will produce waste heat. The necessary 200 [[megawatt]] reactor "with a power-to-mass density of 1,000 [[watt]]s per [[kilogram]]" ([[Franklin Chang D\u00edaz|D\u00edaz]] quote) would require extremely efficient radiators to avoid the need for "football-field sized radiators" ([[Robert Zubrin|Zubrin]] quote).<ref>Video: [https://www.youtube.com/watch?v=myYs4DCCZts#t=870s ''VASIMR Debate/The VASIMR Hoax \u2013 Dr. Robert Zubrin \u2013 14th International Mars Society Convention'', Time Index 14:30]</ref>\n\n {{Div col|colwidth=30em}}\n*[[Comparison of orbital rocket engines]]\nElectric propulsion\n*[[Helicon Double Layer Thruster]]\n*[[Magnetoplasmadynamic thruster]]\n*[[Nano-particle field extraction thruster]]\n*[[Pulsed plasma thruster]]\nSpace fission reactors\n*[[Project Prometheus]]\n*[[Safe Affordable Fission Engine]]\n*[[Systems for Nuclear Auxiliary Power]]\n*[[TOPAZ nuclear reactor]]\n{{colend}}\n\n {{Reflist|30em}}\n\n <!--\nhttp://www.adastrarocket.com/aarc/News\nhttp://www.adastrarocket.com/aarc/PressReleases\n-->\n{{Refbegin}}\n*{{Cite press release |url=http://www.nasa.gov/centers/johnson/news/releases/2006/J06-009.html |title=Agreement to Commercialize Advanced NASA Rocket Concept; Former Astronaut Franklin Chang-Diaz to Lead Effort |publisher=Johnson Space Center |date=January 23, 2006 |access-date=January 18, 2008 |id=J06-009}}\n*{{Cite news |url=http://www.technologyreview.com/Infotech/19427/ |title=Rocket scientist Franklin Chang Diaz talks about finding the power and propulsion required to colonize space |first=Erica |last=Naone |work=Technology Review |date=September 25, 2007 |access-date=February 27, 2010}}\n*{{Cite web |url=http://www.spectrum.ieee.org/aerospace/space-flight/rockets-for-the-red-planet/0 |title=Rockets For The Red Planet |website=IEEE Spectrum |first=Sandra |last=Upson |date=June 2009 |access-date=February 27, 2010 |archive-url=https://web.archive.org/web/20110722082634/http://spectrum.ieee.org/aerospace/space-flight/rockets-for-the-red-planet/0 |archive-date=July 22, 2011 |url-status=dead |df=mdy-all }}\n\n {{Commons category|VASIMR}}\n*[http://science.discovery.com/videos/brink-package-plasma-rocket.html "Plasma Rocket"] (Video). ''[[Brink (TV series)|Brink]]''. [[Science (TV channel)|Science]]. December 18, 2008.\n\n; NASA documents\n*[https://web.archive.org/web/20041016200148/http://ston.jsc.nasa.gov/collections/TRS/_techrep/TP-1995-3539.pdf Technical Paper: Rapid Mars Transits with Exhaust-Modulated Plasma Propulsion (PDF)]\n*[http://www.techbriefs.com/content/view/1768/32/1/0/ Variable-Specific-Impulse Magnetoplasma Rocket (Tech Brief)]\n*[http://spaceflight.nasa.gov/shuttle/support/researching/aspl/vasimr.html Advanced Space Propulsion Laboratory: VASIMR] {{Webarchive|url=https://web.archive.org/web/20150202001541/http://spaceflight.nasa.gov/shuttle/support/researching/aspl/vasimr.html |date=February 2, 2015 }}\n*[http://www.nasa.gov/vision/space/travelinginspace/future_propulsion.html Propulsion Systems of the Future]\n\n{{spacecraft propulsion}}\n{{emerging technologies|topics=yes|space=yes}}", "Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---|Research and development": "The first VASIMR experiment was conducted at [[Massachusetts Institute of Technology]] in 1983. Important refinements were introduced in the 1990s, including the use of the helicon plasma source, which replaced the plasma gun originally envisioned and its electrodes, adding to durability and long life.{{citation_needed|date=June 2019}}\n\nAs of 2010, [[Ad Astra Rocket Company]] (AARC) was responsible for VASIMR development, signing the first [[Space Act Agreement]] on 23 June 2005 to privatize VASIMR technology. [[Franklin Chang D\u00edaz]] is Ad Astra's chairman and CEO, and the company had a testing facility in [[Liberia, Costa Rica]] on the campus of [[EARTH University|Earth University]].<ref name="summary">{{cite web |url=http://www.adastrarocket.com/EXECUTIVE%20SUMMARY240110.pdf |title=Executive summary |date=January 24, 2010 |publisher=Ad Astra Rocket Company |access-date=February 27, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100331171616/http://www.adastrarocket.com/EXECUTIVE%20SUMMARY240110.pdf |archive-date=March 31, 2010 |df=mdy-all }}</ref>\n\n In 1998, the first helicon plasma experiment was performed at the [[Johnson Space Center#Advanced Space Propulsion Laboratory|ASPL]]. VASIMR experiment 10 (VX-10) in 1998 achieved a helicon RF plasma discharge of up to 10 kW and VX-25 in 2002 of up to 25 kW. By 2005 progress at ASPL included full and efficient plasma production and acceleration of the plasma ions with the 50 kW, {{convert|0.5|N|lbf|1}} thrust VX-50.<ref name="Principal VASIMR results"/> Published data on the 50 kW VX-50 showed the electrical efficiency to be 59% based on a 90% coupling efficiency and a 65% ion speed boosting efficiency.<ref name="IEPC-2007-181">{{cite web |url=http://www.adastrarocket.com/Jared_IEPC07.pdf |title=High Power VASIMR Experiments using Deuterium, Neon and Argon |date=September 17\u201320, 2007 |first1=Jared P |last1=Squire |display-authors=etal |publisher=International Electric Propulsion Conference 2007 |access-date=February 27, 2010 |archive-date=February 26, 2015 |archive-url=https://web.archive.org/web/20150226072114/http://www.adastrarocket.com/Jared_IEPC07.pdf |url-status=dead }}</ref>{{failed verification|date=April 2021}}\n\n The 100 kilowatt VASIMR experiment was successfully running by 2007 and demonstrated efficient plasma production with an ionization cost below 100{{nbsp}}eV.<ref name=PR_June_2007>{{cite web|title=Ad Astra's VX-100 test bed achieves record plasma performance|url=http://www.adastrarocket.com/AdAstraPressRelease061207-1.pdf|website=PRESS RELEASE 061207, June 12, 2007|publisher=Ad Astra|access-date=February 7, 2014|archive-date=October 30, 2012|archive-url=https://web.archive.org/web/20121030190312/http://www.adastrarocket.com/AdAstraPressRelease061207-1.pdf|url-status=dead}}</ref> VX-100 plasma output tripled the prior record of the VX-50.<ref name=PR_June_2007/>\n\nThe VX-100 was expected to have an ion speed boosting efficiency of 80%, but could not achieve this efficiency due to losses from the conversion of DC electric current to radio frequency power and the auxiliary equipment for the superconducting magnet.<ref name="IEPC-2007-181"/><ref name="whitepaper">{{cite web |url=http://www.adastrarocket.com/AIAA2006.pdf |title=Recent Improvements In Ionization Costs And Ion Cyclotron Heating Efficiency In The VASIMR Engine |date=January 9\u201312, 2006 |first1=Edgar A |last1=Bering |display-authors=etal |publisher=AIAA Aerospace Sciences Meeting and Exhibit |access-date=February 27, 2010 |archive-date=January 19, 2016 |archive-url=https://web.archive.org/web/20160119120839/http://www.adastrarocket.com/AIAA2006.pdf |url-status=dead }}</ref> In contrast, 2009 state-of-the-art, proven ion engine designs such as NASA's [[High Power Electric Propulsion]] (HiPEP) operated at 80% total thruster/[[power processing unit|PPU]] energy efficiency.<ref name="NASA report">{{cite web |url=ftp://ftp.grc.nasa.gov/users/ep/ion/publications/2004/onsite/aiaa-2004-3453.pdf |title=An Overview of the High Power Electric Propulsion (HiPEP) Project |date=July 11\u201314, 2004 |first1=Frederick W |last1=Elliott |display-authors=etal |publisher=AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit |access-date=February 27, 2010 }}{{dead link|date=January 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>\n\n [[File:VX-200 operation full power.jpg|thumb|upright=1.5|VX-200 plasma engine at full power, employing both stages with full magnetic field]]\nOn 24 October 2008, the company announced in a press release that the [[Helicon (physics)|helicon]] plasma generation component of the 200 kW VX-200 engine had reached operational status. The key enabling technology, solid-state DC-RF power-processing, reached 98% efficiency. The helicon discharge used 30 kW of radio waves to turn [[argon]] gas into plasma. The remaining 170 kW of power was allocated for acceleration of plasma in the second part of the engine, via ion cyclotron resonance heating.<ref name="VASIMR VX-200 first stage">{{cite press release |url=http://www.adastrarocket.com/Release241008.pdf |title=VASIMR VX-200 first stage achieves full power rating |publisher=Ad Astra Rocket Company |date=October 24, 2008 |access-date=February 27, 2010 |archive-date=November 5, 2015 |archive-url=https://web.archive.org/web/20151105185042/http://www.adastrarocket.com/Release241008.pdf |url-status=dead }}</ref>\n\nBased on data from VX-100 testing,<ref name="VASIMR Exceeding 50kW"/> it was expected that, if room temperature superconductors are ever discovered, the VX-200 engine would have a system efficiency of 60\u201365% and a potential thrust level of 5 N. Optimal [[specific impulse]] appeared to be around 5,000 s using low cost argon propellant. One of the remaining untested issues was whether the hot plasma actually detached from the rocket. Another issue was waste heat management. About 60% of input energy became useful kinetic energy. Much of the remaining 40% is secondary ionizations from plasma crossing magnetic field lines and exhaust divergence. A significant portion of that 40% was waste heat (see [[energy conversion efficiency]]). Managing and rejecting that waste heat is critical.<ref>{{cite journal |title=A review of the processing, composition, and temperature-dependent mechanical and thermal properties of dielectric technical ceramics |journal=Journal of Materials Science |volume = 47|issue=10 |pages=4211\u20134235 |first1=Daith\u00ed |last1=de Faoite |first2=David J |last2=Browne |first3=Franklin R |last3=Chang-D\u00edaz |first4=Kenneth T |last4=Stanton |date=November 17, 2011 |doi=10.1007/s10853-011-6140-1|bibcode = 2012JMatS..47.4211F |hdl=10197/8477 |hdl-access=free }}</ref>\n\nBetween April and September 2009, 200 kW tests were performed on the VX-200 prototype with 2 [[tesla (unit)|tesla]] superconducting magnets that are powered separately and not accounted for in any "efficiency" calculations.<ref>{{cite press release |url=http://www.adastrarocket.com/Release_200kW_01Oct2009Final.pdf |title=VASIMR VX-200 reaches 200 kW power milestone |publisher=Ad Astra Rocket Company |date=September 30, 2011 |access-date=February 24, 2012 |archive-date=March 1, 2012 |archive-url=https://web.archive.org/web/20120301192252/http://www.adastrarocket.com/Release_200kW_01Oct2009Final.pdf |url-status=dead }}</ref> During November 2010, long duration, full power firing tests were performed, reaching steady state operation for 25 seconds and validating basic design characteristics.<ref name="VASIMR VX-200 firing for 25 seconds">{{cite web |url=https://www.youtube.com/watch?v=BRS26DcQhq0  |archive-url=https://ghostarchive.org/varchive/youtube/20211211/BRS26DcQhq0| archive-date=2021-12-11 |url-status=live|title=Video of VASIMR VX-200 firing for 25 seconds at full power rating |date=December 15, 2010 |author=Benwl |publisher=Ad Astra Rocket Company |access-date=January 4, 2011}}{{cbignore}}</ref>\n\nResults presented in January 2011 confirmed that the design point for optimal efficiency on the VX-200 is 50 km/s exhaust velocity, or an [[specific impulse|''I''{{sub|sp}}]] of 5000{{nbsp}}s. The 200 kW VX-200 had executed more than 10,000 engine firings with [[argon]] propellant at full power by 2013, demonstrating greater than 70% thruster efficiency relative to RF power input.<ref name=ilin2013>{{cite conference |url=http://www.adastrarocket.com/AndrewIEPC13-336-Paper.pdf |title=VASIMR Solar Powered Missions for NEA Retrieval and NEA Deflection |conference=33rd International Electric Propulsion Conference. October 6\u201310, 2013. Washington, D.C. |first1=Andrew V. |last1=Ilin |first2=Daniel A. |last2=Gilman |first3=Mark D. |last3=Carter |first4=Franklin R. |last4=Chang D\u00edaz |first5=Jared P. |last5=Squire |first6=Joseph E. |last6=Farrias |date=2013 |id=IEPC-2013-336 |access-date=May 14, 2014 |archive-date=May 14, 2014 |archive-url=https://web.archive.org/web/20140514181304/http://www.adastrarocket.com/AndrewIEPC13-336-Paper.pdf |url-status=dead }}</ref>\n\n In March 2015, Ad Astra announced a $10 million award from NASA to advance the technology readiness of the next version of the VASIMR engine, the '''VX-200SS''' to meet the needs of deep space missions.<ref>{{cite press release |url=https://www.nasa.gov/press/2015/march/nasa-announces-new-partnerships-with-us-industry-for-key-deep-space-capabilities/ |title=NASA Announces New Partnerships with U.S. Industry for Key Deep-Space Capabilities |publisher=NASA |date=March 30, 2015 |access-date=July 24, 2021}}</ref> The SS in the name stands for "steady state", as a goal of the long duration test is to demonstrate continuous operation at thermal steady state.<ref>{{cite press release |url=https://adastrarocket.com/AdAstraRelease033115final.pdf |title=Ad Astra Rocket Company wins major NASA advanced propulsion contract |publisher=Ad Astra Rocket Company |date=March 31, 2015 |access-date=July 24, 2021 |archive-date=July 24, 2021 |archive-url=https://web.archive.org/web/20210724083602/https://adastrarocket.com/AdAstraRelease033115final.pdf |url-status=dead }}</ref>\n\nIn August 2016, Ad Astra announced completion of the milestones for the first year of its 3-year contract with NASA. This allowed for first high-power plasma firings of the engines, with a stated goal to reach 100{{nbsp}}hr and 100 kW by mid-2018.<ref>{{cite press release |url=https://adastrarocket.com/pressReleases/AdAstra-Release-080316-final.pdf |title=Ad Astra Rocket Company successfully completes all NASA NextStep Contract Milestones for year one, receives NASA approval to proceed with year two |publisher=Ad Astra Rocket Company |date=August 3, 2016 |access-date=July 24, 2021}}</ref> In August 2017, the company reported completing its Year 2 milestones for the VASIMR electric plasma rocket engine. NASA gave approval for Ad Astra to proceed with Year 3 after reviewing completion of a 10-hour cumulative test of the VX-200SS engine at 100{{nbsp}}kW. It appears as though the planned 200 kW design is being run at 100 kW for reasons that are not mentioned in the press release.<ref name="Ad_Astra_20170809">{{cite press release |url=https://adastrarocket.com/pressReleases/AdAstraRelease080917-final.pdf |title=Ad Astra Rocket Company successfully completes all NASA NextStep Contract Milestones for year two, receives NASA approval to proceed with year three |publisher=Ad Astra Rocket Company |date=August 9, 2017 |access-date=August 9, 2017}}</ref> \n\t \nIn August 2019, Ad Astra announced the successful completion of tests of a new generation radio-frequency ([[RF]]) Power Processing Unit (PPU) for the VASIMR engine, built by [[Aethera Technologies]] Ltd. of Canada.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2019/20190820-AdAstra-Aethera.pdf |title=Aethera's New RF Power Processing Unit for the VASIMR Engine Successfully Completes Full Power Vacuum and Magnetic Field Tests at Ad Astra Rocket Company's Texas Facility |publisher=Ad Astra Rocket Company |date=August 20, 2019 |access-date=July 24, 2021}}</ref> Ad Astra declared a power of 120 [[kW]] and >97% electrical-to-RF power efficiency, and that, at 52 kg, the new RF PPU is about 10x lighter than the PPUs of competing electric thrusters (power-to-weight ratio: 2.31 kW/kg)\n\nIn July 2021, Ad Astra announced the completion of a record-breaking test for the engine, running it for 28 hours at a power level of 82.5{{nbsp}}kW.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2021/20210709-PressRelease.pdf |title=Ad Astra Rocket Company shatters power and endurance record in recent tests of the VASIMR VX-200SS plasma rocket |publisher=Ad Astra Rocket Company |date=July 9, 2021 |access-date=July 15, 2021}}</ref> A second test, conducted from July 12 to 16, successfully ran the engine for 88 hours at a power level of 80{{nbsp}}kW.<ref>{{cite press release |url=https://www.adastrarocket.com/pressReleases/2021/20210722-PressRelease.pdf |title=VASIMR VX-200SS plasma rocket completes record 88-hour high power endurance test |publisher=Ad Astra Rocket Company |date=July 22, 2021 |access-date=July 24, 2021}}</ref> Ad Astra anticipates conducting 100{{nbsp}}kW power level tests in the second half of 2021.", "Variable Specific Impulse Magnetoplasma Rocket --- Introduction ---|Potential applications": "VASIMR has a comparatively poor thrust-to-weight ratio, and requires an ambient vacuum.\n\nProposed applications for VASIMR such as the rapid transportation of people to Mars would require a very high power, low mass energy source, ten times more efficient than a nuclear reactor (see [[nuclear electric rocket]]). In 2010 NASA Administrator [[Charles Bolden]] said that VASIMR technology could be the breakthrough technology that would reduce the travel time on a Mars mission from 2.5 years to 5 months.<ref name='Morring'>{{cite journal|last1=Morring |first1=Frank |date=2010 |title=Commercial Route |journal=Aviation Week & Space Technology |volume=172 |issue=6 |pages=20\u201323 }}</ref> However this claim has not been repeated in the last decade.\n\nIn August 2008, Tim Glover, Ad Astra director of development, publicly stated that the first expected application of VASIMR engine is "hauling things [non-human cargo] from low-Earth orbit to low-lunar orbit" supporting NASA's return to Moon efforts.<ref name="Discovery News">{{cite web |url=http://dsc.discovery.com/news/2008/08/07/plasma-rocket.html |title=Plasma Rocket May Be Tested at Space Station |date=August 7, 2008 |author=Irene Klotz |publisher=Discovery News |access-date=February 27, 2010 }}</ref>\n\n In order to conduct an imagined crewed trip to Mars in 39 days,<ref>Video: "[https://www.youtube.com/watch?v=-nyepvfuHho Mars in 39 Days?: the VASIMR Plasma Engine. Franklin Chang-Diaz, Ph.D.]"</ref> the VASIMR would require an electrical power level far beyond anything currently possible or predicted.\n\nOn top of that, any power generation technology will produce waste heat. The necessary 200 [[megawatt]] reactor "with a power-to-mass density of 1,000 [[watt]]s per [[kilogram]]" ([[Franklin Chang D\u00edaz|D\u00edaz]] quote) would require extremely efficient radiators to avoid the need for "football-field sized radiators" ([[Robert Zubrin|Zubrin]] quote).<ref>Video: [https://www.youtube.com/watch?v=myYs4DCCZts#t=870s ''VASIMR Debate/The VASIMR Hoax \u2013 Dr. Robert Zubrin \u2013 14th International Mars Society Convention'', Time Index 14:30]</ref>"}},
{"article_title": "Space technology", "pageid": "40375", "revid": "1046754617", "timestamp": "2021-09-27T08:12:15Z", "history_paths": [["Space technology --- Introduction ---", "History of space technology"]], "categories": ["space technology"], "heading_tree": {"Space technology --- Introduction ---": {"History of space technology": {}, "Hazards caused by space technology": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Space technology --- Introduction ---|History of space technology": "{{see also|Astronautics|}}\nThe first country on Earth to put any technology into space was [[Soviet Union]], formally known as the "Union of Soviet Socialist Republics" (USSR). The USSR sent the [[Sputnik 1]] satellite on October 4, 1957. It weighed about {{convert|83|kg|lb|abbr=on}}, and is believed to have orbited Earth at an altitude of about {{convert|250|km|mi|abbr=on}}. It had two radio transmitters (20 and 40 MHz), which emitted "beeps" that could be heard by radios around the globe. Analysis of the radio signals was used to gather information about the electron density of the ionosphere, while temperature and pressure data was encoded in the duration of radio beeps.\n\nThe first successful human spaceflight was ''[[Vostok 1]]'', carrying 27-year-old Soviet cosmonaut [[Yuri Gagarin]] in April 1961. The entire mission was controlled by either automatic systems or by [[Mission control center|ground control]]. This was because medical staff and spacecraft engineers were unsure how a human might react to weightlessness, and therefore it was decided to lock the pilot's manual controls.<ref name=oleg>{{cite news |url=https://www.telegraph.co.uk/news/obituaries/11111713/Oleg-Ivanovsky-obituary.html#disqus_thread |title=Oleg Ivanovsky - obituary |work=The Daily Telegraph |date=September 21, 2014 |access-date=September 25, 2014}}</ref><ref>Burgess and Hall, p.156</ref>\n\nThe first artto reach a [[heliocentric orbit]] around the Sun.<ref name=nssdc>{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1959-012A|title=Luna 1|website=NASA Space Science Data Coordinated Archive}}</ref> The first probe to impact the surface of the Moon was the Soviet probe [[Luna 2]], whicsalut salu saluth made a hard landing on September 14, 1959. The far side of the Moon was first photographed on October 7, 1959, by the Soviet probe [[Luna 3]].s\nOn December 24, 1968, the crew of [[Apollo 8]], [[Frank Borman]], [[Jim Lovell|James Lovell]] and [[William Anders]], became the first human beings to enter lunar orbit and see the far side of the Moon in person. Humans first landed on the Moon on July 20, 1969. The first human to walk on the lunar surface was [[Neil Armstrong]], commander of [[Apollo 11]].\n\nApollo 11 was followed by [[Apollo 12]], [[Apollo 14|14]], [[Apollo 15|15]], [[Apollo 16|16]], and [[Apollo 17|17]]. [[Apollo 13]] had a failure of the [[Apollo service module]], but passed the [[far side of the Moon]] at an altitude of {{convert|254|km|mi nmi|sp=us|abbr=off}} above the lunar surface, and 400,171 km (248,655 mi) from Earth, marking the [[List of spaceflight records|record]] for the farthest humans have ever traveled from Earth in 1970.\n\nThe first robotic [[lunar rover]] to land on the Moon was the Soviet vessel [[Lunokhod 1]] on November 17, 1970, as part of the [[Lunokhod programme|Lunokhod program]]. To date, the last human to stand on the Moon was [[Eugene Cernan]], who as part of the [[Apollo 17]] mission, walked on the Moon in December 1972. Apollo 17 was followed by several uncrewed interplanetary missions operated by NASA.\n\nOne of the notable interplanetary missions is ''[[Voyager 1]]'', the first artificial object to [[List of artificial objects leaving the Solar System|leave our Solar System]] into [[Outer space#Interstellar space|interstellar space]] on August 25, 2012. It is also the most distant artificial object from Earth.<ref>{{cite web |url=http://www.bbc.co.uk/science/space/solarsystem/space_missions/voyager_1 |title=Voyager 1 |work=[[BBC]] Solar System |access-date=4 September 2018 |archive-url=https://web.archive.org/web/20180203195855/http://www.bbc.co.uk/science/space/solarsystem/space_missions/voyager_1 |archive-date=February 3, 2018 |url-status=dead |df=mdy-all }}</ref> The probe passed the [[Heliopause (astronomy)#Heliopause|heliopause]] at 121 [[Astronomical unit|AU]] to enter [[Interstellar medium|interstellar space]].<ref>{{cite news |title=Voyager 1 finally crosses into interstellar space |first=William|last=Harwood |work=[[CBS News]] |date=September 12, 2013 |url=http://www.cbsnews.com/8301-205_162-57602736/voyager-1-finally-crosses-into-interstellar-space/}}</ref> ''Voyager 1'' is currently at a distance of {{convert|145.11|AU|sigfig=5}} (21.708 billion kilometers; 13.489 billion miles) from Earth as of January 1, 2019.<ref name="voyager">{{cite web | url=https://voyager.jpl.nasa.gov/mission/status/ | title=Voyager - Mission Status | work=[[Jet Propulsion Laboratory]] | publisher=[[NASA]] | access-date=January 1, 2019}}</ref>"}},
{"article_title": "Closed captioning", "pageid": "40883", "revid": "1062947484", "timestamp": "2021-12-31T09:46:10Z", "history_paths": [["Closed captioning --- Introduction ---", "History  {{anchor|Open captioning}}"]], "categories": ["subtitling", "assistive technology", "deafness", "television terminology", "high-definition television", "transcription (linguistics)"], "heading_tree": {"Closed captioning --- Introduction ---": {"Terminology": {}, "History  {{anchor|Open captioning}}": {"Open captioning": {}, "Technical development of closed captioning": {}, "Full-scale closed captioning": {}, "Legislative development in the U.S.": {}, "Philippines": {}, "Legislative development in Australia": {}, "Funding development in New Zealand": {}}, "Application": {}, "Television and video": {"Caption formatting": {"Syntax": {}, "Technical aspects": {}}, "Caption channels": {}}, "Digital television interoperability issues": {"Incompatibility issues with digital TV": {}, "New Zealand": {}, "Digital television standard captioning improvements": {}}, "Uses in other media": {"DVDs and Blu-ray Discs": {}, "Movies": {}, "Sports venues": {}, "Video games": {}, "Online video streaming": {}, "Theatre": {}, "Telephones": {}, "Video conferencing": {}, "Media monitoring services": {}, "Conversations": {}, "Non-linear video editing systems and closed captioning": {}}, "Logo": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Closed captioning --- Introduction ---|History  {{anchor|Open captioning}}": "Regular open-captioned broadcasts began on [[Public Broadcasting Service|PBS]]'s ''[[The French Chef]]'' in 1972.<ref name="caphist">{{cite web|url=http://www.ncicap.org/caphist.asp |title=A Brief History of Captioned Television |url-status=dead |archive-url=https://web.archive.org/web/20110719060406/http://www.ncicap.org/caphist.asp |archive-date=2011-07-19 }}</ref> [[WGBH-TV|WGBH]] began open captioning of the programs ''[[Zoom (1972 TV series)|Zoom]]'', ''[[ABC World News Tonight]]'', and ''[[Once Upon a Classic]]'' shortly thereafter.\n\n Closed captioning was first demonstrated in the United States at the First National Conference on Television for the Hearing Impaired in Nashville, Tennessee, in 1971.<ref name="caphist" /> A second demonstration of closed captioning was held at Gallaudet College (now [[Gallaudet University]]) on February 15, 1972, where [[American Broadcasting Company|ABC]] and the [[National Bureau of Standards]] demonstrated closed captions embedded within a normal broadcast of ''[[The Mod Squad]]''.\nAt the same time in the UK the BBC was demonstrating its Ceefax text based broadcast service which they were already using as a foundation to the development of a closed caption production system. They were working with Professor [[Alan Newell (English computer scientist)|Alan Newell]] from the University of Southampton who had been developing prototypes in the late 1960s.\n\nThe closed captioning system was successfully encoded and broadcast in 1973 with the cooperation of PBS station [[WETA-TV|WETA]].<ref name="caphist" /> As a result of these tests, the FCC in 1976 set aside line 21 for the transmission of closed captions. PBS engineers then developed the caption editing consoles that would be used to caption prerecorded programs.\n\nThe [[BBC]] in the UK was the first broadcaster to include closed captions (subtitles in the UK) in 1979 based on the [[Teletext]] framework for pre-recorded programming.\n\nReal-time captioning, a process for captioning live broadcasts, was developed by the [[National Captioning Institute]] in 1982.<ref name="caphist" /> In real-time captioning, [[stenotype]] operators who are able to type at speeds of over 225 words per minute provide captions for live television programs, allowing the viewer to see the captions within two to three seconds of the words being spoken.\n\nMajor US producers of captions are [[WGBH-TV]], [[VITAC]], [[CaptionMax]] and the [[National Captioning Institute]]. In the UK and [[Australasia]], Ai-Media, [[Red Bee Media]], itfc, and Independent Media Support are the major vendors.\n\nImprovements in [[speech recognition]] technology means that live captioning may be fully or partially automated.  [[BBC Sport]] broadcasts use a "respeaker": a trained human who repeats the running commentary (with careful enunciation and some simplification and [[markup language|markup]]) for input to the automated text generation system. This is generally reliable, though errors are not unknown.<ref>{{cite web|url=https://www.bbc.com/news/uk-england-tyne-41473443|title=Match of the Day 2: Newcastle subtitle error leaves BBC red-faced|date=2 October 2017|work=[[BBC Online]]|access-date=2 October 2017}}</ref>\n\n The National Captioning Institute was created in 1979 in order to get the cooperation of the commercial television networks.<ref name="ncicap1">{{Cite web|url=http://www.ncicap.org/caphist.asp|archive-url=https://web.archive.org/web/20110719060406/http://www.ncicap.org/caphist.asp|url-status=dead|title=National Captioning Institute<!-- Bot generated title -->|archive-date=July 19, 2011}}</ref>\n\nThe first use of regularly scheduled closed captioning on American television occurred on March 16, 1980.<ref>Gannon, Jack. 1981. ''Deaf Heritage-A Narrative History of Deaf America''. Silver Spring, MD: National Association of the Deaf, pp. 384-387</ref> [[Sears]] had developed and sold the Telecaption adapter, a decoding unit that could be connected to a standard television set. The first programs seen with captioning were a ''[[Walt Disney anthology series|Disney's Wonderful World]]'' presentation of the film ''[[Son of Flubber]]'' on [[NBC]], an ''[[The ABC Sunday Night Movie|ABC Sunday Night Movie]]'' airing of ''[[Semi-Tough]]'', and ''[[Masterpiece Theatre]]'' on [[Public Broadcasting Service|PBS]].<ref>"Today on TV", ''Chicago Daily Herald'', March 11, 1980, Section 2-5</ref>\n\nSince 2010 BBC provides a 100% broadcast captioning service across all 7 of its main broadcast channels [[BBC One]], [[BBC Two]], [[BBC Three]], [[BBC Four]], [[CBBC (TV channel)|CBBC]], [[Cbeebies]] and [[BBC News (TV channel)]].\n\n[[BBC iPlayer]] launched in 2008 as the first captioned [[Video on demand]] service from a major broadcaster meeting comparable levels of captioning provided on its broadcast channels.\n\n Until the passage of the Television Decoder Circuitry Act of 1990, television captioning was performed by a set-top box manufactured by Sanyo Electric and marketed by the National Captioning Institute (NCI). (At that time a set-top decoder cost about as much as a TV set itself, approximately $200.) Through discussions with the manufacturer it was established that the appropriate circuitry integrated into the television set would be less expensive than the stand-alone box, and Ronald May, then a Sanyo employee, provided the expert witness testimony on behalf of Sanyo and Gallaudet University in support of the passage of the bill. On January 23, 1991, the [[Television Decoder Circuitry Act of 1990]] was passed by Congress.<ref name="caphist" /> This Act gave the [[Federal Communications Commission]] (FCC) power to enact rules on the implementation of Closed Captioning. This Act required all analog television receivers with screens of at least 13 inches or greater, either sold or manufactured, to have the ability to display closed captioning by July 1, 1993.<ref>{{Cite web|url=https://www.access-board.gov/sec508/guide/1194.24-decoderact.htm|title=Crossing at Roundabouts - United States Access Board|website=www.access-board.gov}}</ref>\n\nAlso, in 1990, the [[Americans with Disabilities Act]] (ADA) was passed to ensure equal opportunity for persons with disabilities.<ref name="ncicap1" /> The ADA prohibits discrimination against persons with disabilities in public accommodations or commercial facilities. Title III of the ADA requires that public facilities\u2014such as hospitals, bars, shopping centers and museums (but not movie theaters)\u2014provide access to verbal information on televisions, films or slide shows.\n\nThe Federal Communications Commission requires all providers of programs to caption material which has audio in English or Spanish, with certain exceptions specified in Section 79.1(d) of the Commission's rules. These exceptions apply to new networks; programs in languages other than English or Spanish; networks having to spend over 2% of income on captioning; networks having less than US$3,000,000 in revenue; and certain local programs; among other exceptions.<ref>{{Cite web|url=https://www.fcc.gov/general/self-implementing-exemptions-closed-captioning-rules|title=Self Implementing Exemptions From Closed Captioning Rules|date=July 8, 2011|website=Federal Communications Commission}}</ref> Those who are not covered by the exceptions may apply for a hardship waiver.<ref>{{Cite web|url=https://www.fcc.gov/economically-burdensome-exemption-closed-captioning-requirements|title=Economically Burdensome Exemption from Closed Captioning Requirements|date=May 30, 2017|website=Federal Communications Commission}}</ref>\n\nThe [[Telecommunications Act of 1996]] expanded on the Decoder Circuity Act to place the same requirements on [[digital television]] receivers by July 1, 2002.<ref>{{Cite web|url=https://www.fcc.gov/consumers/guides/closed-captioning-television|title=Closed Captioning on Television|date=May 6, 2011|website=Federal Communications Commission}}</ref> All TV programming distributors in the U.S. are required to provide closed captions for Spanish-language video programming as of January 1, 2010.<ref>{{Cite web|url=http://www.fcc.gov/cgb/dro/captioning_regs.html|title=Part 79 - Closed Captioning of Video Programming|url-status=live|archive-url=https://web.archive.org/web/20040513111535/http://www.fcc.gov/cgb/dro/captioning_regs.html|archive-date=13 May 2004}}</ref>\n\nA bill, H.R. 3101, the Twenty-First Century Communications and Video Accessibility Act of 2010, was passed by the United States House of Representatives in July 2010.<ref>{{cite web|title=Twenty-First Century Communications and Video Accessibility Act of 2010|year=2010|url=http://www.govtrack.us/congress/bills/111/hr3101|access-date=2013-03-28}}</ref> A similar bill, S. 3304, with the same name, was passed by the United States Senate on August 5, 2010, by the House of Representatives on September 28, 2010, and was signed by President [[Barack Obama]] on October 8, 2010. The Act requires, in part, for [[Advanced Television Systems Committee standards|ATSC]]-decoding set-top box remotes to have a button to turn on or off the closed captioning in the output signal. It also requires broadcasters to provide captioning for television programs redistributed on the Internet.<ref>{{cite web|title=Twenty-First Century Communications and Video Accessibility Act of 2010|year=2010|url=http://www.govtrack.us/congress/bills/111/s3304|access-date=2013-03-28}}</ref>\n\nOn February 20, 2014, the FCC unanimously approved the implementation of quality standards for closed captioning,<ref>{{cite web|title=FCC Moves to Upgrade TV Closed Captioning Quality|year=2014|url=http://www.fcc.gov/document/fcc-moves-upgrade-tv-closed-captioning-quality}}</ref> addressing accuracy, timing, completeness, and placement. This is the first time the FCC has addressed quality issues in captions.\n\n As amended by RA 10905, all TV networks in the Philippines are required to give CC.<ref>{{Cite web|url=https://www.kbp.org.ph/philippine-tv-to-provide-closed-captioning|title=Philippine TV to Provide Closed Captioning \u2013 Kapisanan ng mga Brodkaster ng Pilipinas|website=www.kbp.org.ph}}</ref> As of 2018, the three major TV networks in the country are currently testing the closed captioning system on their transmissions. [[ABS-CBN]] added CC in their daily [[Chaplet of the Divine Mercy|3 O'Clock Habit]] in the afternoon. [[5 (TV channel)|5]] started implementing CCs on their live noon and nightly news programs. [[GMA Network|GMA]] was once started broadcasting nightly and late night news programs, but then they stopped adding CCs lately. Only select [[Korean drama]] and local or foreign movies, ''Biyahe ni Drew'' (English: ''Drew's Explorations'') and ''Idol sa Kusina'' (English: ''Kitchen Idol'') are the programs and shows that they air with proper closed captioning.<ref>{{cite web|url=https://www.yugatech.com/news/gma-tv5-now-airing-shows-with-closed-captioning/#SlhAodUTy5JM4oD4.99|title=GMA, TV5 now airing shows with closed captioning\n|author=Carl Lamiel|date=October 14, 2017|publisher=YugaTech|access-date=February 2, 2019}}</ref>\n\nClose Captioning in some Filipino Films either to be "included" if film production companies have a bias on having impact on their viewing experience for those who did not understand the language nor not understand what it heard to it or distributed internationally. Since 2016, all Filipino-Language Films and also on some Streaming Services like iWant had included their English Subtitles in some showing on films. The Law regarding do that was passed by Gerald Anthony Gullas Jr. a lawmaker from Cebu City had implemented the regulations on standardizing both official languages of the Philippines as the people had not well fluently in those mastering their English vocabulary.<ref>{{cite web|url=https://www.rappler.com/entertainment/40688-lawmaker-wants-english-subtitles-ph-tv-movies|title=Lawmaker wants English subtitles for PH TV, movies|date=October 6, 2013|publisher=[[Rappler]]|access-date=September 6, 2019}}</ref>\n\n The government of Australia provided [[seed funding]] in 1981 for the establishment of the Australian Caption Centre (ACC) and the purchase of equipment. Captioning by the ACC commenced in 1982 and a further grant from the Australian government enabled the ACC to achieve and maintain financial self-sufficiency. The ACC, now known as [[Media Access Australia]], sold its commercial captioning division to [[Red Bee Media]] in December 2005. Red Bee Media continues to provide captioning services in Australia today.<ref>{{cite web\n |url         = http://www.dbcde.gov.au/__data/assets/pdf_file/0020/84710/Media_Access_Australia_-_Response_to_Media_Access_Review_2008.pdf\n |title       = Submission to DBCDE's investigation into Access to Electronic Media for the Hearing and Vision Impaired\n |access-date  = 2009-02-07\n |author1     = Alex Varley\n |date        = June 2008\n |publisher   = Media Access Australia\n |location    = Australia\n |pages       = 12, 18, 43\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20090326214643/http://www.dbcde.gov.au/__data/assets/pdf_file/0020/84710/Media_Access_Australia_-_Response_to_Media_Access_Review_2008.pdf\n |archive-date = 2009-03-26\n}}</ref><ref>{{cite web|url=http://www.mediaaccess.org.au/index.php?option=com_content&view=article&id=359&Itemid=100|title=About Media Access Australia|publisher=Media Access Australia|location=Australia|url-status=live|archive-url=https://web.archive.org/web/20090101180233/http://www.mediaaccess.org.au/index.php?option=com_content&view=article&id=359&Itemid=100|archive-date=1 January 2009|access-date=2009-02-07}}</ref><ref>{{cite web|url=http://www.redbeemedia.com.au/aboutus-australia.html |title=About Red Bee Media Australia |access-date=2009-02-07 |publisher=Red Bee Media Australia Pty Limited |location=Australia |url-status=dead |archive-url=https://web.archive.org/web/20090613004348/http://www.redbeemedia.com.au/aboutus-australia.html |archive-date=June 13, 2009 }}</ref>\n\n In 1981, [[TVNZ]] held a [[telethon]] to raise funds for Teletext-encoding equipment used for the creation and editing of text-based broadcast services for the deaf. The service came into use in 1984 with caption creation and importing paid for as part of the public broadcasting fee until the creation of the [[NZ on Air]] taxpayer fund, which is used to provide captioning for [[NZ On Air]] content, TVNZ news shows and conversion of [[EIA-608]] US captions to the preferred [[EBU]] STL format for only [[TVNZ 1]], [[TV 2 (New Zealand)|TV 2]] and [[TV3 (New Zealand)|TV 3]] with archived captions available to [[Four (New Zealand)|FOUR]] and select [[SKY Network Television|Sky]] programming. During the second half of 2012, [[TV3 (New Zealand)|TV3]] and [[Four (New Zealand)|FOUR]] began providing non-Teletext DVB image-based captions on their HD service and used the same format on the satellite service, which has since caused major timing issues in relation to server load and the loss of captions from most SD DVB-S receivers, such as the ones Sky Television provides their customers. As of April 2, 2013, only the Teletext page 801 caption service will remain in use with the informational Teletext non-caption content being discontinued."}},
{"article_title": "Companding", "pageid": "40927", "revid": "994787689", "timestamp": "2020-12-17T15:05:36Z", "history_paths": [["Companding --- Introduction ---", "History"]], "categories": ["lossy compression algorithms", "audio engineering", "sound recording technology"], "heading_tree": {"Companding --- Introduction ---": {"How it works": {}, "Applications": {}, "History": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Companding --- Introduction ---|History": "The use of companding in an analog picture transmission system was patented by A. B. Clark of [[American Telephone & Telegraph|AT&T]] in 1928 (filed in 1925):<ref>{{Ref patent\n |country= US\n |number=\n |status= patent\n |title= [http://www.google.com/patents?id=XElKAAAAEBAJ&dq=patent:1691147 Electrical picture-transmitting system]\n |gdate= 1928-11-13\n |fdate= 1925-06-06\n |inventor= A. B. Clark\n |invent1= Clark, A. B.\n |assign1= AT&T\n}}</ref>\n\n{{quote|In the transmission of pictures by electric currents, the method which consists in sending currents varied in a non-linear relation to the light values of the successive elements of the picture to be transmitted, and at the receiving end exposing corresponding elements of a sensitive surface to light varied in inverse non-linear relation to the received current.|A. B. Clark patent}}\n\nIn 1942, Clark and his team completed the [[SIGSALY]] secure voice transmission system that included the first use of companding in a PCM (digital) system.<ref>{{cite book | title = Wireless Security: Models, Threats, and Solutions | author = Randall K. Nichols and Panos C. Lekkas | publisher = McGraw-Hill Professional | year = 2002 | isbn = 0-07-138038-8 | url = https://archive.org/details/wirelesssecurity00nich| url-access = registration | page = [https://archive.org/details/wirelesssecurity00nich/page/256 256] | quote = companding a-b-clark pcm. }}</ref>\n\nIn 1953, B. Smith showed that a nonlinear DAC could be complemented by the inverse nonlinearity in a successive-approximation ADC configuration, simplifying the design of digital companding systems.<ref>B. Smith, "Instantaneous Companding of Quantized Signals," ''Bell System Technical Journal'', Vol. 36, May 1957, pp. 653\u2013709.</ref>\n\nIn 1970, H. Kaneko developed the uniform description of segment (piecewise linear) companding laws that had by then been adopted in digital telephony.<ref>H. Kaneko, "A Unified Formulation of Segment Companding Laws and Synthesis of Codecs and Digital Compandors," ''Bell System Technical Journal'', Vol. 49, September 1970, pp. 1555\u20131558.</ref>\n\nIn the 1980s (and '90s), many of the music equipment manufacturers ([[Roland Corporation|Roland]], [[Yamaha Corporation|Yamaha]], [[Korg]]) used companding when compressing the library waveform data in their [[Digital synthesizer|digital synthesizers]]. Unfortunately exact algorithms are not known, neither if any of the manufacturers ever used the Companding scheme which is described in this article. The only known thing is that manufacturers did use data compression <ref>[[Eric Persing]], sound designer ([[Roland Corporation|Roland]], Spectrasonics), 29th May 2010 https://www.gearslutz.com/board/showpost.php?p=5446278&postcount=130</ref> in the mentioned time period and that some people refer to it as "companding" while in reality it might mean something else, for example data compression and expansion.<ref>Dave Polich, sound designer, 13th January 2018 https://www.gearslutz.com/board/showpost.php?p=13068220&postcount=146</ref> This dates back to the late '80s when memory chips were often one of the most costly components in the instrument. Manufacturers usually quoted the amount of memory in its compressed form: i.e. 24 MB of physical waveform ROM in a [[Korg Trinity]] is actually 48 MB when uncompressed. Similarly, Roland SR-JV expansion boards were usually advertised as 8 MB boards with '16 MB-equivalent content'. Careless copying of this technical information, omitting the "equivalence" reference, can often cause confusion."}},
{"article_title": "Datagram", "pageid": "40994", "revid": "1060233958", "timestamp": "2021-12-14T06:43:02Z", "history_paths": [["Datagram --- Introduction ---", "History"]], "categories": ["units of information", "packets (information technology)"], "heading_tree": {"Datagram --- Introduction ---": {"History": {}, "Definition": {}, "Structure": {}, "Examples": {"Internet Protocol": {}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Datagram --- Introduction ---|History": "In the early 1970s, the term ''datagram'' was created by combining the words ''data'' and ''telegram'' by the [[ITU-T|CCITT]] rapporteur on packet switching,<ref>{{cite web|title=The CCITT studies packet switching as part of public data network development|url=https://www.deepdyve.com/lp/association-for-computing-machinery/the-ccitt-studies-packet-switching-as-part-of-public-data-network-TU05NzohPP}}</ref> [[Halvor Bothner-By]].<ref>{{cite web|title=X.25 virtual circuits \u2014 Transpac in France \u2014 Pre-Internet data networking|url=https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5621965}}</ref><ref>{{cite web|url=http://old.open-root.eu/la-doc/histoire-des-reseaux/le-datagramme/|url-status=dead|archive-url=https://web.archive.org/web/20190228065633/http://old.open-root.eu/la-doc/histoire-des-reseaux/le-datagramme/|archive-date=2019-02-28|title=Comment j\u2019ai invent\u00e9 le Datagramme|language=fr}}</ref>\n\nWhile the word was new, the concept had already a long history.\n\nIn 1962, [[Paul Baran]] described, in a [[RAND Corporation]] report, an hypothetical military network having to resist a nuclear attack. Small standardized "message blocks", bearing source and destination addresses, were [[Store and forward|stored and forwarded]] in computer nodes of a highly redundant meshed computer network.<ref>{{cite web|title=\nOn distributed communications networks|url=http://pages.cs.wisc.edu/~akella/CS740/F08/740-Papers/Bar64.pdf|url-status=dead|archive-url=https://web.archive.org/web/20161026145448/https://pages.cs.wisc.edu/~akella/CS740/F08/740-Papers/Bar64.pdf|archive-date=2016-10-26}}</ref> "The network user who has called up a "virtual connection" to an end station and has transmitted messages ... might also view the system as a black box providing an apparent circuit connection".\n\nIn 1967, [[Donald Davies]] published a seminal article in which he introduced the now largely used words [[Network packet|''packet'']] and ''[[packet switching]]''.<ref>{{cite web|title=A digital communication network for computers giving rapid response at remote terminals|url=https://people.mpi-sws.org/~gummadi/teaching/sp07/sys_seminar/how_did_erope_blow_this_vision.pdf}}</ref> \nHis core network is similar to that of Paul Baran although it has been independently designed. To deal with datagram permutations (due to dynamically updated routing preferences) and to datagram losses (unavoidable when fast sources send to a slow destinations), he  assumes that "all users of the network will provide themselves with some kind of error control" (what will be called later on a ''pure datagram'' service). His target is, for the first time in packet switching, a "common-carrier communication network". To support remote access to computer services by user terminals, which at that time transmitted in general character by character, he included at the network periphery interface computers that convert character flows into packet flows and conversely.  \n \nIn 1970, Lawrence Roberts and Barry D. Wessler published an article about [[ARPANET]], the first multi-node packet-switching network.<ref>{{cite web|url=https://www.researchgate.net/profile/Lawrence_Roberts/publication/234815171_Computer_Network_Development_to_Achieve_Resource_Sharing/links/546d0ac50cf2193b94c57d5a/Computer-Network-Development-to-Achieve-Resource-Sharing.pdf|title=Computer network development to achieve resource sharing|author1=Lawrence Roberts|author2=Barry D. Wessler|year=1970|doi=10.1145/1476936.1477020}}</ref> An accompanying paper described its switching nodes (the IMPs) and its packet formats.<ref>{{cite web|author1=Frank E Heart|author2=R E Kahn|author3=Severo M Ornstein|author4=William R Crowther|author5=David C Walden|url=https://dl.acm.org/doi/10.1145/1476936.1477021|doi=10.1145/1476936.1477021|title=The interface message processor for the ARPA computer network}}</ref> The network core performed datagram switching as in Baran's and Davies' model, but provision was added within the network, at its periphery, to deal with datagram losses and permutations. A reliable message transfer service was thus offered to user computers, thus greatly simplifying their own work, and keeping it less dependent on further research.\n\nIn 1973, [[Louis Pouzin]] presented his design for [[CYCLADES|Cyclades]], the first real size network implementing the pure datagram model of Donald Davies.<ref>{{cite web|title=Presentation and major design aspects of the Cyclades network|url=http://rogerdmoore.ca/PS/CYCLB.html|archive-url=https://web.archive.org/web/20070927205826/http://rogerdmoore.ca/PS/CYCLB.html|archive-date=September 27, 2007}}\n</ref>\nThe Cyclades team has thus been first to tackle the highly complex problem of providing to user applications a reliable virtual circuit service (the equivalent of an Internet [[Transmission Control Protocol|TCP]] connection)<ref>{{cite IETF|rfc=1379|title=Extending TCP for transactions -- Concepts}}</ref> while using an end to end network service known to possibly produce non negligible datagram losses and permutations. \nAlthough Pouzin's concern "in a first stage is not to make breakthrough in packet switching technology, but to build a reliable communications tool for Cyclades", two members of his team, [[Hubert Zimmerman]] and [[G\u00e9rard Le Lann]], made significant contributions to the design of Internet's TCP that [[Vint Cerf]], its main designer, acknowledged.<ref>{{cite IETF|title=Specification of Internet transmission control program|rfc=675}}\n</ref>\n\nIn 1981, the Defense Advanced Research Projects Agency ([[DARPA]]) issued the first specification the [[Internet protocol]] (IP). It introduced a major evolution of the datagram concept: ''[[IP fragmentation|fragmentation]].''<ref>{{cite IETF|title=Internet protocol - Darpa Internet program protocol specification|rfc=791}}</ref> \nWith fragmentation, some parts of the global network may use large packet size (typically [[local area network]]s for processing power minimization), while some others may impose smaller packet sizes (typically [[wide area network]]s for response time minimization). Network nodes may split a packet of a datagram into several smaller packets of the same datagram.\n\nIn 1999, the [[Internet Engineering Task Force]] (IETF) officialised the use of the already largely deployed ''[[Network address translation]]'' (NAT)\nwhereby each public address can be shared by several private devices.<ref>{{cite IETF|title=IP network address translator (NAT) terminology and considerations|rfc=2663}}</ref> With it, the forthcoming [[IPv4 address exhaustion|Internet Address exhaustion]] was delayed, leaving enough time to introduce [[IPv6]], the new generation of Internet packets supporting longer addresses. The initial principle of full [[End-to-end principle|end to end]] network transparency to datagrams was for this relaxed: NAT nodes had to manage per-connection states, making them in part [[Connection-oriented communication|connection oriented]].\n\nIn 2015, the [[IETF]] upgraded its weak "informational" recommendation of 1998, that datagram switching nodes perform [[active queue management]] (AQM), to make it a  stronger and more detailed "[[best current practice]]" recommendation.<ref>{{cite IETF|title=IETF recommendations regarding active queue management|rfc=7567}}</ref> \nWhile the initial datagram queueing model was simple to implement and needed no more tuning than queue lengths, support of more sophisticated and parametrized mechanisms were found necessary "to improve and preserve Internet performance" ([[Random Early Detection|RED]], [[Explicit Congestion Notification|ECN]] etc.). Further research on the subject was also called for, with a list of identified items."}},
{"article_title": "Pulse dialing", "pageid": "41024", "revid": "1053069099", "timestamp": "2021-11-01T18:24:39Z", "history_paths": [["Pulse dialing --- Introduction ---", "Early automatic exchanges"], ["Pulse dialing --- Introduction ---", "Rotary dial"], ["Pulse dialing --- Introduction ---", "Pulse rate and coding"], ["Pulse dialing --- Introduction ---", "Successors"]], "categories": ["obsolete technologies", "telephony signals"], "heading_tree": {"Pulse dialing --- Introduction ---": {"Early automatic exchanges": {}, "Rotary dial": {}, "Pulse rate and coding": {}, "Switch-hook dialing": {}, "Successors": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Pulse dialing --- Introduction ---|Early automatic exchanges": "Automatic [[telephone exchange]] systems were developed in the late 19th and early 20th century. For identification, telephone subscribers were assigned a [[telephone number]] unique to each circuit. Various methods evolved to signal the desired destination telephone number for a telephone call directly dialed by the subscriber. An automatic switch-hook was designed by [[Hilborne Roosevelt]].<ref>{{Cite Appletons'|wstitle=Roosevelt, Nicholas I.|year=1900|author=Isa Carrington Cabell |short=x}}</ref>\n\nThe first commercial automatic telephone exchange, designed by [[Almon Brown Strowger]], opened in [[La Porte, Indiana|La Porte]], [[Indiana]] on 3 November 1892, and used two telegraph-type keys on the telephone, which had to be operated the correct number of times to control the vertical and horizontal relay magnets in the exchange. But the use of separate keys with separate conductors to the exchange was not practical. The most common signaling system became a system of using direct-current pulse trains generated in the telephone sets of subscribers by interrupting the single-pair wire loop of the telephone circuit.", "Pulse dialing --- Introduction ---|Rotary dial": "Strowger also filed the first [[patent]] for a rotary dial in 1891. The first dials worked by direct, forward action. The pulses were sent as the user rotated the dial to the finger stop starting at a different position for each digit transmitted. Operating the dial error-free required smooth rotary motion of the finger wheel by the user, but was found as too unreliable. This mechanism was soon refined to include a recoil spring and a [[centrifugal governor]] to control the recoil speed. The user selected a digit to be dialed by inserting a finger into the corresponding hole and rotated the dial to the finger stop. When released from this position, the dial pulsing contacts were opened and closed repeatedly, thus interrupting the loop current in a pattern on the return to the home position. The exchange switch decoded the pattern for each digit thus transmitted by stepping relays or by accumulation in digit registers.", "Pulse dialing --- Introduction ---|Pulse rate and coding": "[[File:Bakelittelefon 1947a.jpg|thumb|Swedish phone with one pulse for 0]]\nIn the first electromechanical switching systems the current pulses generated by the rotary dial on the local loop directly operated electrical stepping switches at the central office. The mechanical nature of these relays generally limited the speed of operation, the pulsing rate, to ten pulses per second.\n\nThe specifications of the Bell System in the US required service personnel to adjust dials in customer stations to a precision of 9.5 to 10.5 pulses per second (PPS), but the tolerance of the switching equipment was generally between 8 and 11 PPS.<ref>AT&T Specification No. 4566, February 1926, p.113</ref> The British (GPO, later [[Post Office Telecommunications]]) standard for  [[Strowger switch]] exchanges has been ten impulses per second (allowable range 7 to 12) and a 66% break ratio (allowable range 63% to 72%)<ref>J. Atkinson, ''Telephony'' Volume 1, p.142 (1948, Pitman, London)</ref><ref>Current UK standard  [http://www.sinet.bt.com/sinet/SINs/pdf/351v4p6.pdf BT SIN 351]</ref>\n\nIn most switching systems one pulse is used for the digit 1, two pulses for 2, and so on, with ten pulses for the digit 0; this makes the code [[unary numeral system|unary]], excepting the digit 0. Exceptions to this are: Sweden, with one pulse for 0, two pulses for 1, and so on; and New Zealand with ten pulses for 0, nine pulses for 1, etc. Oslo, the capital city of Norway, used the New Zealand system, but the rest of the country did not. Systems that used this encoding of the ten digits in a sequence of up to ten pulses, are known as decadic dialing systems.\n\nSome switching systems used digit registers that doubled the allowable pulse rate up to twenty pulses per second, and the inter-digital pause could be reduced as the switch selection did not have to be completed during the pause. These included access lines to the [[Panel switch]] in the 1920s, Crossbar systems, the later version (7A2) of the [[Rotary system]], and the earlier 1970s [[stored program control]] exchanges.\n\nIn some telephones, the pulses may be heard in the receiver as clicking sounds. However, in general, such effects were undesirable and telephone designers suppressed them by mechanical means with off-normal switches on the dial, or greatly attenuated them by electrical means with a [[varistor]] connected across the receiver.", "Pulse dialing --- Introduction ---|Successors": "It was recognized as early as the 1940s that dialing could be faster and more accurate with push buttons, but this was too unreliable in customer trials until transistors transformed the industry. In 1963, the Bell System introduced to the public [[dual-tone multi-frequency]] (DTMF) technology under the name Touch-Tone, which was a trademark in the U.S. until 1984.<ref>The Trademark Electronic Search System on the [[U.S. Patent and Trademark Office]] [http://www.uspto.gov/ web site] shows the trademark with serial number 72109459, registered 1962-09-04 and cancelled 1984-03-13.</ref> The Touch-Tone system used [[push-button telephone]]s. In the decades after 1963, rotary dials were gradually phased out on new telephone models in favor of keypads and the primary dialing method to the central office became touchtone dialing, but most central office systems still support rotary telephones today. Some keypad telephones have a switch or configuration method for the selection of tone or pulse dialing.\n\n[[Mobile telephone]]s and most [[voice-over-IP]] systems use [[out-of-band signaling]] and do not send any digits until the entire number has been keyed by the user. Many VoIP systems are based on the [[Session Initiation Protocol]] (SIP), which uses a form of [[Uniform Resource Identifier]]s (URI) for addressing, instead of digits alone."}},
{"article_title": "Lidar", "pageid": "41958", "revid": "1062682774", "timestamp": "2021-12-29T22:36:23Z", "history_paths": [["Lidar --- Introduction ---", "History and etymology"]], "categories": ["lidar", "meteorological instrumentation and equipment", "robotic sensing", "articles containing video clips", "emerging technologies"], "heading_tree": {"Lidar --- Introduction ---": {"History and etymology": {"General description": {}}, "Technology": {"Design": {}, "Components": {"Laser": {"Phased arrays": {}, "Microelectromechanical machines": {}}, "Scanner and optics": {}, "Photodetector and receiver electronics": {}, "Position and navigation systems": {}, "Sensor": {}}, "Flash Lidar": {}}, "Classification": {"Based on orientation": {}, "Based on scanning mechanism": {}, "Based on platform": {"Airborne": {"Airborne lidar bathymetry": {}}, "Terrestrial": {}}}, "Applications": {"Agriculture": {"Plant species classification": {}}, "Archaeology": {}, "Autonomous vehicles": {"Object detection for transportation systems": {"GRID based processing using 3-D lidar and fusion with radar measurement": {}, "Fusion of 3-D lidar and color camera for multiple object detection and tracking": {}, "Obstacle detection and road environment recognition using lidar": {}}}, "Biology and conservation": {}, "Geology and soil science": {}, "Atmosphere": {"Scheimpflug principle": {}}, "Law enforcement": {}, "Military": {}, "Mining": {}, "Physics and astronomy": {}, "Rock mechanics": {}, "Robotics": {}, "Spaceflight": {}, "Surveying": {}, "Transport": {}, "Wind farm optimization": {}, "Solar photovoltaic deployment optimization": {}, "Video games": {}, "Other uses": {}}, "Alternative technologies": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Lidar --- Introduction ---|History and etymology": "Under the direction of [[Malcolm Stitch]], the [[Hughes Aircraft Company]] introduced the first lidar-like system in 1961,<ref>{{cite news |title=New Radar System |work=Odessa American |date=28 Feb 1961}}</ref><ref name="Macomber">{{cite news |last1=Macomber |first1=Frank |title=Space Experts Seek Harness for Powerful LASER Light |url=https://0-access.newspaperarchive.com.alec.icpl.org/us/california/bakersfield/bakersfield-californian/1963/06-03/page-5/?pep=colidar-mark&psb=dateasc&page=3&pci=7 |access-date=11 July 2019 |work=Bakersfield Californian |agency=Copley News Service |issue=p. 5 |date=June 3, 1963}}</ref> shortly after the invention of the laser. Intended for satellite tracking, this system combined laser-focused imaging with the ability to calculate distances by measuring the time for a signal to return using appropriate sensors and data acquisition electronics. It was originally called "Colidar" an acronym for "coherent light detecting and ranging,"<ref name="stitch">{{cite journal |last1=Stitch |journal=Electronics |date=21 April 1961 |volume=51 |page=2 }}</ref> derived from the term "[[radar]]", itself an acronym for "radio detection and ranging". All laser [[rangefinder]]s, laser altimeters and lidar units are derived from the early colidar systems. The first practical terrestrial application of a colidar system was the "Colidar Mark II", a large rifle-like laser rangefinder produced in 1963 which had a range of 7 miles and an accuracy of 15 feet, to be used for military targeting.<ref>{{cite news |title=Laser Measures Distance |work=Lincoln Journal Star |issue=p. 6 |date=29 March 1963}}</ref><ref name="Macomber" /> The first mention of lidar as a stand-alone word in 1963 suggests it originated as a portmanteau of "[[light]]" and "radar": "Eventually the laser may provide an extremely sensitive detector of particular wavelengths from distant objects. Meanwhile, it is being used to study the moon by 'lidar' (light radar) ..."<ref name="James Ring p. 672-3">James Ring, "The Laser in Astronomy." pp. 672\u201373, ''New Scientist'' June 20, 1963.</ref><ref name=Oxford>{{cite book|title= Oxford English Dictionary|year=2013|page=Entry for "lidar"|url= http://www.oed.com/}}</ref>\nThe name "[[photonic radar]]" is sometimes used to mean visible-spectrum range finding like lidar.<ref name="auto2">{{Cite web|url=https://www.technion.ac.il/en/2016/05/19138/|title=Photonic Radar {{!}} Technion - Israel Institute of Technology|website=www.technion.ac.il|date=27 May 2016|language=en-US|access-date=2018-08-12}}</ref><ref name="auto1">{{Cite web|url=http://fullafterburner.weebly.com/next-gen-weapons/radio-optic-phased-array-radar-a-comprehensive-study|title=Radio Optic Phased Array Radar - a comprehensive study.|website=Full Afterburner|language=en|access-date=2018-08-12}}</ref>\n\nLidar's first applications were in meteorology, for which the [[National Center for Atmospheric Research]] used it to measure [[clouds]] and pollution.<ref name=Goyer>{{cite journal|last= Goyer|first= G. G.|author2=R. Watson |title= The Laser and its Application to Meteorology|journal= Bulletin of the American Meteorological Society|date= September 1963|volume=44|issue= 9|pages= 564\u2013575 [568]|doi= 10.1175/1520-0477-44.9.564|bibcode= 1963BAMS...44..564G|doi-access= free}}</ref> The general public became aware of the accuracy and usefulness of lidar systems in 1971 during the [[Apollo 15]] mission, when astronauts used a laser altimeter to map the surface of the moon.\nAlthough the English language no longer treats "radar" as an acronym, (i.e., uncapitalized), the word "lidar" was capitalized as "LIDAR" or "LiDAR" in some publications beginning in the 1980s. No consensus exists on capitalization. Various publications refer to lidar as "LIDAR", "LiDAR", "LIDaR", or "Lidar". The [[USGS]] uses both "LIDAR" and "lidar", sometimes in the same document;<ref>{{cite web|url=http://lidar.cr.usgs.gov/ |title=CLICK |website=Lidar.cr.usgs.gov |date=2015-09-16 |access-date=2016-02-22 |url-status=dead |archive-url=https://web.archive.org/web/20160219045753/http://lidar.cr.usgs.gov/ |archive-date=2016-02-19 }}</ref> the ''[[New York Times]]'' predominantly uses "lidar" for staff-written articles,<ref>{{cite web|url=https://query.nytimes.com/search/sitesearch/?action=click&contentCollection=Science&region=TopBar&WT.nav=searchWidget&module=SearchSubmit&pgtype=article#/lidar/since1851/document_type%3A%22article%22/ |title=NYTimes.com search |website=nytimes.com |access-date=2017-04-07}}</ref> although contributing news feeds such as Reuters may use Lidar.<ref>{{cite web|url=https://www.nytimes.com/reuters/2017/03/29/technology/29reuters-uber-tech-alphabet-lawsuit.html |title=Waymo Self-Driving Unit Sought Arbitration Over Engineer Now at Uber|website=nytimes.com |date=2017-03-29 |access-date=2017-04-07}}</ref>\n\n Lidar uses [[ultraviolet]], [[Interferometric visibility|visible]], or [[near infrared]] light to image objects. It can target a wide range of materials, including non-metallic objects, rocks, rain, chemical compounds, [[aerosols]], clouds and even single [[molecule]]s.<ref name="cracknell" /> A narrow laser beam can map physical features with very high [[Optical resolution|resolutions]]; for example, an aircraft can map terrain at {{convert|30|cm|adj=on}} resolution or better.<ref>{{cite web|author1=Carter, Jamie|author2=Keil Schmid|author3=Kirk Waters|author4=Lindy Betzhold|author5=Brian Hadley|author6=Rebecca Mataosky|author7=Jennifer Halleran|title=Lidar 101: An Introduction to Lidar Technology, Data, and Applications." (NOAA) Coastal Services Center|date=2012|page=14| url=https://coast.noaa.gov/data/digitalcoast/pdf/lidar-101.pdf |website=Coast.noaaa.gov|access-date=2017-02-11}}</ref>\n{{\nmultiple image | align = right | direction = horizontal | total_width = 700\n| image1 = 20200501 Time of flight.svg | caption1 =Basic time-of-flight principles applied to laser range-finding\n| image2 = Amazon Canopy Comes to Life through Laser Data.webm| caption2= Flying over the Brazilian Amazon with a LIDAR instrument.\n| image3 =  Collecting LIDAR data over the Ganges and Brahmaputra River Basin.ogg| caption3=Animation of a satellite collecting digital elevation map data over the Ganges and Brahmaputra River basin using lidar.\n}}\nThe essential concept of lidar was originated by [[EH Synge]] in 1930, who envisaged the use of powerful searchlights to probe the atmosphere.<ref>Philosophical Magazine and Journal of Science, 1930, Series 7, Volume 9, Issue 60, pp. 1014\u20131020</ref><ref>Donegan, J.F.; ''[https://www.livingedition.at/en/isbn/9783901585173/ The Life and Works of Edward Hutchinson Synge]'' pp. 31, 67, (co-edited with D. Weaire and [[Petros Serghiou Florides|P. Florides]]), P\u00f6llauberg, Austria : Living Edition, {{ISBN|3901585176}}</ref> Indeed, lidar has since been used extensively for atmospheric research and [[meteorology]]. Lidar instruments fitted to [[aircraft]] and [[satellite]]s carry out [[surveying]] and mapping \u2013 a recent example being the U.S. Geological Survey Experimental Advanced Airborne Research Lidar.<ref>'Experimental Advanced Advanced Research Lidar', ''USGS.gov''. Retrieved 8 August 2007.</ref> [[NASA]] has identified lidar as a key technology for enabling autonomous precision safe landing of future robotic and crewed lunar-landing vehicles.<ref name="auto">{{cite journal|author1=Amzajerdian, Farzin |author2=Pierrottet, Diego F. |author3=Petway, Larry B. |author4=Hines, Glenn D. |author5=Roback, Vincent E. |title=Lidar Systems for Precision Navigation and Safe Landing on Planetary Bodies|url=https://ntrs.nasa.gov/search.jsp?R=20110012163|journal=International Symposium on Photoelectronic Detection and Imaging 2011: Laser Sensing and Imaging; and Biological and Medical Applications of Photonics Sensing and Imaging|volume=8192 |pages=819202 |access-date=May 24, 2011|date=2011-05-24 |bibcode=2011SPIE.8192E..02A |doi=10.1117/12.904062 |hdl=2060/20110012163 |s2cid=28483836 |hdl-access=free}}</ref>\n\nWavelengths vary to suit the target: from about 10 [[micrometer (unit)|micrometer]]s ([[infrared]]) to approximately 250 [[nanometer|nm]] ([[Ultraviolet|UV]]). Typically, light is reflected via [[backscatter]]ing, as opposed to pure reflection one might find with a mirror. Different types of scattering are used for different lidar applications: most commonly [[Rayleigh scattering]], [[Mie scattering]], [[Raman scattering]], and [[fluorescence]].<ref name="cracknell" /> Suitable combinations of wavelengths can allow for remote mapping of atmospheric contents by identifying wavelength-dependent changes in the intensity of the returned signal.<ref>{{Cite book|url=https://books.google.com/books?id=zGlQDwAAQBAJ&pg=PA678|title=Handbook of Optoelectronics: Concepts, Devices, and Techniques (Volume One)|last1=P. Dakin|first1=John|last2=Brown|first2=Robert|publisher=CRC Press|year=2017|isbn=978-1-4822-4179-2|page=678}}</ref>\nThe name "photonic radar" is sometimes used to mean visible-spectrum range finding like lidar,<ref name="auto2"/><ref name="auto1"/> although [[photonic radar]] more strictly refers to radio-frequency range finding using [[photonics]] components."}},
{"article_title": "Data communication", "pageid": "42168", "revid": "1058376508", "timestamp": "2021-12-03T04:31:41Z", "history_paths": [["Data communication --- Introduction ---", "Applications and history"]], "categories": ["data transmission", "computer networking", "mass media technology", "telecommunications"], "heading_tree": {"Data communication --- Introduction ---": {"Distinction between related subjects": {}, "Protocol layers and sub-topics": {}, "Applications and history": {}, "Serial and parallel transmission": {}, "Communication channels": {}, "Asynchronous and synchronous data transmission": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Data communication --- Introduction ---|Applications and history": "Data (mainly but not exclusively [[information]]al) has been sent via non-electronic (e.g. [[optical]], [[acoustics|acoustic]], [[Classical mechanics|mechanical]]) means since the advent of [[communication]]. [[Analog signal]] data has been sent electronically since the [[History of the telephone|advent of the telephone]]. However, the first data electromagnetic transmission applications in modern time were [[telegraphy]] (1809) and [[teletypewriter]]s (1906), which are both [[Digital signal (electronics)|digital signal]]s. The fundamental theoretical work in data transmission and information theory by [[Harry Nyquist]], [[Ralph Hartley]], [[Claude Shannon]] and others during the early 20th century, was done with these applications in mind.\n\nData transmission is utilized in [[computers]] in [[computer bus]]es and for communication with [[peripheral equipment]] via [[parallel port]]s and [[serial port]]s such as [[RS-232]] (1969), [[FireWire]] (1995) and [[USB]] (1996). The principles of data transmission are also utilized in storage media for [[Error detection and correction#Data storage|Error detection and correction]] since 1951.\n\nData transmission is utilized in [[computer networking]] equipment such as [[modems]] (1940), [[local area network]]s (LAN) adapters (1964), [[repeater]]s, [[repeater hub]]s, [[microwave link]]s, [[wireless access point|wireless network access point]]s (1997), etc.\n\nIn telephone networks, digital communication is utilized for transferring many phone calls over the same copper cable or fiber cable by means of [[pulse-code modulation]] (PCM), i.e. sampling and digitization, in combination with [[Time division multiplexing]] (TDM) (1962). [[Telephone exchange]]s have become digital and software controlled, facilitating many value added services. For example, the first [[AXE telephone exchange]] was presented in 1976. Since the late 1980s, digital communication to the end user has been possible using [[Integrated Services Digital Network]] (ISDN) services. Since the end of the 1990s, broadband access techniques such as [[ADSL]], [[Cable modem]]s, [[fiber-to-the-building]] (FTTB) and [[fiber-to-the-home]] (FTTH) have become widespread to small offices and homes. The current tendency is to replace traditional telecommunication services by packet mode communication such as [[IP telephony]] and [[IPTV]].\n\nTransmitting analog signals digitally allows for greater [[Digital signal processing|signal processing]] capability. The ability to process a communications signal means that errors caused by random processes can be detected and corrected. Digital signals can also be [[sampling (signal processing)|sampled]] instead of continuously monitored. The [[multiplexing]] of multiple digital signals is much simpler to the multiplexing of analog signals.\n\nBecause of all these advantages, and because recent advances in [[wideband]] [[communication channel]]s and [[solid-state electronics]] have allowed scientists to fully realize these advantages, digital communications has grown quickly. Digital communications is quickly edging out analog communication because of the vast demand to transmit computer data and the ability of digital communications to do so.\n\nThe digital revolution has also resulted in many digital [[telecommunication]] applications where the principles of data transmission are applied. Examples are [[2G|second-generation]] (1991) and later [[cellular telephony]], [[video conferencing]], [[digital TV]] (1998), [[digital radio]] (1999), [[telemetry]], etc.\n\nData transmission, digital transmission or digital communications is the physical transfer of data (a digital bit stream or a digitized analog signal[1]) over a point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optical fibers, wireless communication channels, storage media and computer buses. The data are represented as an electromagnetic signal, such as an electrical voltage, radiowave, microwave, or infrared signal.\n\nWhile analog transmission is the transfer of a continuously varying analog signal over an analog channel, digital communications is the transfer of discrete messages over a digital or an analog channel. The messages are either represented by a sequence of pulses by means of a line code (baseband transmission), or by a limited set of continuously varying wave forms (passband transmission), using a digital modulation method. The passband modulation and corresponding demodulation (also known as detection) is carried out by modem equipment. According to the most common definition of digital signal, both baseband and passband signals representing bit-streams are considered as digital transmission, while an alternative definition only considers the baseband signal as digital, and passband transmission of digital data as a form of digital-to-analog conversion.\n\nData transmitted may be digital messages originating from a data source, for example a computer or a keyboard. It may also be an analog signal such as a phone call or a video signal, digitized into a bit-stream for example using pulse-code modulation (PCM) or more advanced source coding (analog-to-digital conversion and data compression) schemes. This source coding and decoding is carried out by codec equipment."}},
{"article_title": "Whistle", "pageid": "42387", "revid": "1055847789", "timestamp": "2021-11-18T04:38:43Z", "history_paths": [["Whistle --- Introduction ---", "History"]], "categories": ["internal fipple flutes", "whistles", "blown percussion instruments", "english musical instruments", "sports officiating technology"], "heading_tree": {"Whistle --- Introduction ---": {"History": {"Early whistles": {}, "Joseph Hudson": {}}, "Typical sources and uses": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Whistle --- Introduction ---|History": "[[File:Carved whalebone whistle dated 1821. London. 8 cm long.jpg|thumb|Carved [[whalebone]] whistle dated 1821. 8 cm long.]]\nWhistles made of bone or wood have been used for thousands of years.\n\nWhistles were used by the Ancient Greeks to keep the stroke of [[galley]] slaves. The English used whistles during the [[Crusades]] to signal orders to archers. Boatswain pipes were also used in the [[age of sail]] aboard naval vessels to issue commands and salute dignitaries.<ref>{{cite web|title=Whistle|url=http://www.madehow.com/Volume-4/Whistle.html|website=How Products are Made|access-date=22 January 2018}}</ref>\n\n \n[[Joseph Hudson (inventor)|Joseph Hudson]] set up [[J Hudson & Co]] in Birmingham, UK in 1870. With his younger brother James, he designed the 'Acme City' brass whistle. This became the first referee whistle used at association football matches during the [[1878\u201379 FA Cup|1878\u201379 Football Association Cup]] match between Nottingham Forest and Sheffield. Prior to the introduction of the whistle, handkerchiefs were used by the umpires to signal to the players.<ref name="auto">{{Cite web|url=https://www.gdfra.org.au/history_of_the_whistle.htm|title=History of the Whistle|website=Gdfra.org.au|access-date=12 January 2021}}</ref>\n\n[[File:Bobbypfeife.ogg|thumb|A police whistle being blown]]\nIn 1883 he began experimenting with pea-whistle designs that could produce an intense sound that could grab attention from over a mile away. His invention was discovered by accident, when he accidentally dropped his violin and it shattered on the floor. Observing how the discordant sound of the breaking strings travelled ([[Trill (music)|trill effect]]), Hudson had the idea to put a pea in the whistle.<ref name="auto"/> Prior to this, whistles were much quieter, and were only thought of as musical instruments or toys for children. After observing the problems that local police were having with effectively communicating with rattles,<ref>{{cite web|last=Cross|first=David|title=On the Beat in Birmingham - Rules and regulations|url=https://www.bbc.co.uk/history/british/victorians/beat_01.shtml|publisher=BBC|access-date=11 March 2014|date=2011-02-17|quote=Police whistles came much later; the early Victorian constable would have carried a small wooden rattle.}}</ref><ref name="taylor">Taylor, J. [https://web.archive.org/web/20050218125210/http://www.constabulary.com/mystery/rattle.htm "The Victorian Police Rattle Mystery"]\n\n''The Constabulary'' (2003) {{webarchive |url=https://web.archive.org/web/20100218043036/http://www.constabulary.com/mystery/rattle.htm |date=February 18, 2010 }}</ref> he realised that his whistle designs could be used as an effective aid to their work.<ref name="acme">{{Cite web|url=https://www.acmewhistles.co.uk/the-first-whistle|title=The First Whistle|website=Acmewhistles.co.uk|access-date=12 January 2021}}</ref>\n\nHudson demonstrated his whistle to [[Scotland Yard]] and was awarded his first contract in 1884. Both Ratchet rattles and whistles were used to call for back-up in areas where neighbourhood beats overlapped, and following their success in London, the whistle was adopted by most police in the United Kingdom (UK).\n\nThis police whistle monopoly gradually made Hudson the largest whistle manufacturer in the world, supplying police forces and other general services everywhere. His whistle is still used by many forces worldwide. His design, was improved as the 'Acme Thunderer', the first ever pea whistle, which remains the most used whistle in the world; for train guards, dog handlers and police officers. From the 1880s and 1890s, J. Hudson & Co began facing greater competition, as other whistle manufacturing companies were established, including W. Dowler & Sons, J. Barrall, R. A. Walton, H. A. Ward and A. De Courcy & Co. In 1987, Ron Foxcroft released the Fox 40 pealess whistle, designed to replace the pea whistle and be more reliable."}},
{"article_title": "Video CD", "pageid": "42803", "revid": "1062164955", "timestamp": "2021-12-26T18:57:02Z", "history_paths": [["Video CD --- Introduction ---", "Brief history"]], "categories": ["audiovisual introductions in 1993", "compact disc", "video storage", "information technology in japan", "information technology in the netherlands", "japanese inventions", "science and technology in japan", "science and technology in the netherlands"], "heading_tree": {"Video CD --- Introduction ---": {"Brief history": {}, "Technical specifications": {"Structure": {}, "Video": {}, "Audio": {}, "Advantages of compression": {}, "Other features": {}}, "Similar formats": {"CD-i Digital Video": {}, "XVCD": {}, "KVCD": {}, "DVCD": {}, "DVI": {}, "SVCD": {}}, "Adoption": {"In North America": {}, "In Asia": {}, "Worldwide trends": {}}, "Compared with VHS": {}, "Compared with DVD": {}, "Hardware and software support": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Video CD --- Introduction ---|Brief history": "{{disputed section|date=January 2020}}\n[[LaserDisc]] was first available on the market, in [[Atlanta, Georgia]], on December 15, 1978.<ref name="CED magic">{{Citation |title=1979: The VideoDisc Is Here! |url=http://www.cedmagic.com/history/discovision-marketed.html |work=History of Media Technology |publisher=CED magic |access-date=8 April 2011}}</ref> This {{convert|30|cm|abbr=on}} disc could hold an hour of analog audio and video (digital audio was added a few years later) on each side. The LaserDisc provided picture quality nearly double that of VHS tape and analog audio quality far superior to cheap mono VHS recorders (although the difference to the more expensive VHS HiFi stereo recorders was minuscule).\n\nPhilips later teamed up with [[Sony]] to develop a new type of disc, the [[compact disc]] or CD. Introduced in 1982 in Japan (1983 in the U.S. and Europe), the CD is about {{convert|120|mm|abbr=on}} in diameter, and is single-sided. The format was initially designed to store digitized sound and proved to be a success in the music industry.\n\nA few years later, Philips decided to give CDs the ability to produce video, utilizing the same technology as its LaserDisc counterpart. This led to the creation of [[CD Video]] (CD-V) in 1987. However, the disc's small size significantly impeded the ability to store analog video; thus only 5 minutes of picture information could fit on the disc's surface (despite the fact that the audio was digital). Therefore, CD-V distribution was limited to featuring music videos, and it was soon discontinued by 1991.\n\nBy the early 1990s engineers were able to digitize and compress video signals, greatly improving storage efficiency.  Because this new format could hold 74/80 minutes of audio and video on a 650/700MB disc, releasing movies on compact discs finally became a reality. Extra capacity was obtained by sacrificing the [[error correction]] <!-- Mode 2 Form 2 recording ---> (it was believed that minor errors in the datastream would go unnoticed by the viewer). This format was named Video CD or VCD.\n\n[[File:Copy Protected VCD.jpg|thumb|\u201cCopy Protected\u201d logo on a VCD package produced in [[Hong Kong]].]]\nVCD enjoyed a brief period of success, with a few major feature films being released in the format (usually as a 2 disc set). However the introduction of the CD-R disc and associated recorders stopped the release of feature films in their tracks because the VCD format had no means of preventing unauthorized (and perfect) copies from being made.{{citation needed|date=August 2017}} However, {{asof|lc=true|2013}} VCDs are still being released in several countries in Asia, but now with copy-protection.{{citation needed|date=September 2019}}\n\nThe development of more sophisticated, higher capacity optical disc formats yielded the [[DVD]] format, released only a few years later with a copy protection mechanism. DVD players use lasers that are of shorter wavelength than those used on CDs, allowing the recorded pits to be smaller, so that more information can be stored. The DVD was so successful that it eventually pushed VHS out of the video market once suitable recorders became widely available. Nevertheless, VCDs made considerable inroads into developing nations, where they are still in use today due to their cheaper manufacturing and retail costs.{{citation needed|date=January 2018}}"}},
{"article_title": "Trebuchet", "pageid": "43380", "revid": "1062734014", "timestamp": "2021-12-30T05:50:24Z", "history_paths": [["Trebuchet --- Introduction ---", "History"]], "categories": ["artillery of china", "chinese inventions", "medieval artillery", "medieval siege engines", "obsolete technologies", "song dynasty"], "heading_tree": {"Trebuchet --- Introduction ---": {"Etymology and terminology": {}, "Basic design": {}, "History": {"Traction trebuchet": {}, "Counterweight trebuchet": {}, "Decline of military use": {}}, "Other trebuchets": {"Hand-trebuchet": {}, "Hybrid trebuchet": {}, "Couillard": {}}, "Comparison of different artillery weapons": {"Roman torsion engines": {}, "Chinese trebuchets": {}, "Siege crossbows": {}, "Reconstructed traction trebuchets": {}, "Reconstructed counterweight trebuchets": {}}, "Modern use": {"Recreation and education": {}, "Developments": {}, "Uses in activism and insurgency": {}}, "Gallery": {}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Trebuchet --- Introduction ---|History": "[[File:Wheeled trebuchet wjzy.jpg|thumb|Wheeled whirlwind traction trebuchet from the ''[[Wujing Zongyao]]'']]\n[[File:Jind\u0159ich VI. obl\u00e9h\u00e1 Neapol (1191).jpg|thumb|[[Siege of Naples (1191)]]]]\n[[File:Perriere from french book of 1250.jpg|thumb|13th-century depiction of a traction trebuchet]]\n[[File:1285 \u0645\u0642\u0630\u0627\u0641.jpg|thumb|[[Muslim]] traction trebuchet, 1285]]\n\n {{see also|Chinese siege weapons|Torsion mangonel myth}} \nThe traction trebuchet, also referred to as a [[mangonel]] in some sources, is thought to have originated in ancient China.<ref name="Chevedden">Chevedden, Paul E.; et al. (July 1995). "The Trebuchet". Scientific American: 66\u201371. [http://static.sewanee.edu/physics/PHYSICS103/trebuchet.pdf. Original version.]</ref><ref name=Trebuchet>[http://www.medievalists.net/2013/01/13/the-trebuchet/ The Trebuchet], Citation: "The trebuchet, invented in China between the fifth and third centuries B.C.E., reached the Mediterranean by the sixth century C.E. "</ref><ref name=PAUL>Paul E. Chevedden, [http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf The Invention of the Counterweight Trebuchet: A Study in Cultural Diffusion] {{webarchive|url=https://web.archive.org/web/20140610032737/http://www.doaks.org/resources/publications/dumbarton-oaks-papers/dop54/dp54ch4.pdf |date=2014-06-10 }}, pp. 71, 74, See citation:"The traction trebuchet, invented by the Chinese sometime before the fourth century B.C." in p. 74</ref> Torsion-based siege weapons such as the [[ballista]] and [[onager (weapon)|onager]] are not known to have been used in China.{{sfn|Graff|2016|p=86}}\n\nThe first recorded use of traction trebuchets was in ancient China. They were probably used by the [[Mohist]]s as early as 4th century BC; descriptions can be found in the [[Mozi|''Mojing'']] (compiled in the 4th century BC).<ref name=Trebuchet/><ref name=PAUL/> According to the ''Mojing'', the traction trebuchet was 17 feet high with four feet buried below ground, the fulcrum attached was constructed from the wheels of a cart, the throwing arm was 30 to 35 feet long with three quarters above the pivot and a quarter below to which the ropes are attached, and the sling two feet and eight inches long. The range given for projectiles are 300, 180, and 120 feet. They were used as defensive weapons stationed on walls and sometimes hurled hollowed out logs filled with burning charcoal to destroy enemy siege works.{{sfn|Liang|2006}}{{sfn|Needham|1994|p=207-209}} By the 1st century AD, commentators were interpreting other passages in texts such as the ''[[Zuo zhuan]]'' and ''[[Classic of Poetry]]'' as references to the traction trebuchet: "the guai is 'a great arm of wood on which a stone is laid, and this by means of a device [ji] is shot off and so strikes down the enemy.'"{{sfn|Needham|1994|p=206}} The ''[[Records of the Grand Historian]]'' say that "The flying stones weigh 12 catties and by devices [ji] are shot off 300 paces."{{sfn|Needham|1994|p=206}} Traction trebuchets went into decline during the [[Han dynasty]] due to long periods of peace but became a common siege weapon again during the [[Three Kingdoms]] period. They were commonly called stone-throwing machines, thunder carriages, and stone carriages in the following centuries.{{sfn|Needham|1994|p=210}} They were used as ship mounted weapons by 573 for attacking enemy fortifications.{{sfn|Needham|1994|p=210}} It seems that during the early 7th century, improvements were made on traction trebuchets, although it is not explicitly stated what. According to a stele in [[Bark\u00f6l Kazakh Autonomous County|Barkul]] celebrating [[Tang Taizong]]'s conquest of what is now [[Ejin Banner]], the engineer Jiang Xingben made great advancements on trebuchets that were unknown in ancient times. Jiang Xingben participated in the construction of siege engines for Taizong's [[Emperor Taizong's campaign against the Western Regions|campaigns against the Western Regions]].{{sfn|Needham|19861994|p=214-215}} In 617 [[Li Mi (Sui dynasty)]] constructed 300 trebuchets for his assault on [[Luoyang]], in 621 [[Li Shimin]] did the same at Luoyang, and onward into the [[Song dynasty]] when in 1161, trebuchets operated by [[Song dynasty]] soldiers fired bombs of lime and sulphur against the ships of the [[Jin dynasty (1115\u20131234)|Jin dynasty]] navy during the [[Battle of Caishi]].<ref>{{cite book|first=Joseph|last=Needham|title=Science and Civilisation in China: Military technology: The Gunpowder Epic, Volume 5, Part 7|year=1987|publisher=Cambridge University Press|isbn=978-0-521-30358-3|page=166}}</ref><ref>{{cite book|first=Herbert|last=Franke|editor=Denis C. Twitchett|editor2=Herbert Franke|editor3=John King Fairbank|title=The Cambridge History of China: Volume 6, Alien Regimes and Border States, 710\u20131368|year=1994|publisher=Cambridge University Press|isbn=978-0-521-24331-5|pages=241\u2013242}}</ref>\n\n{{quotation|For the trebuchet they use large baulks of wood to make the framework, fixing it on four wheels below. From this there rise up two posts having between them a horizontal bar which carries a single arm so that the top of\nthe machine is like a swape. The arm is arranged as to height, length and size, according to the city [which it is proposed to attack or defend]. At the end of the arm there is a sling which holds the stone or stones, of weight and number depending on the stoutness of the arm. Men [suddenly] pull [ropes attached to the other] end, and so shoot it forth. The carriage framework can be pushed and turned around at will. Alternatively the ends [of the beams of the framework] can be buried in the ground and so used. [But whether you use] the 'Whirlwind' type or the 'Four-footed' type depends upon the circumstances.{{sfn|Needham|1994|p=211}}|Li Quan}}\n\nThe traction trebuchet was carried westward by the [[Pannonian Avars|Avars]] and appeared next in the eastern Mediterranean by the late 6th century AD, where it replaced torsion powered siege engines such as the ballista and onager. The rapid displacement of torsion siege engines was probably due to a combination of reasons. The traction trebuchet is simpler in design, has a faster rate of fire, increased accuracy, and comparable range and power. It was probably also safer than the twisted cords of torsion weapons, "whose bundles of taut sinews stored up huge amounts of energy even in resting state and were prone to catastrophic failure when in use."{{sfn|Peterson|2013|p=409}}{{sfn|Purton|2009|p=366}}<ref name="Chevedden"/>{{sfn|Graff|2016|p=141}} At the same time, the late [[Roman Empire]] seems to have fielded "considerably less artillery than its forebears, organised now in separate units, so the weaponry that came into the hands of successor states might have been limited in quantity."{{sfn|Purton|2009|p=364}} Evidence from [[Gaul]] and [[Germania]] suggests there was substantial loss of skills and techniques in artillery further west.{{sfn|Purton|2009|p=364}}\n\nAccording to the ''[[Miracles of Saint Demetrius]]'', probably written around 620 by John, [[Metropolis of Thessaloniki|Archbishop of Thessaloniki]], the Avaro-[[Slavs]] attacked [[Thessaloniki]] in 586 with traction trebuchets. The bombardment lasted for hours, but the operators were inaccurate and most of the shots missed their target. When one stone did reach their target, it "demolished the top of the rampart down to the walkway."{{sfn|Purton|2009|p=30}} The [[Byzantine Empire|Byzantines]] adopted the traction trebuchet possibly as early as 587, the [[Sasanian Empire|Persians]] in the early 7th century, and the [[Umayyad Caliphate|Arabs]] in the second half of the 7th century.{{sfn|Graff|2016|p=86}} Like the Chinese, by 653, the Arabs also had ship mounted traction trebuchet.{{sfn|Purton|2009|p=47}} The [[Franks]] and [[Saxons]] adopted the weapon in the 8th century.{{sfn|Purton|2009|p=367}} The ''[[Vita Hludovici|Life of Louis the Pious]]'' contains the earliest western European reference to mangonels (traction trebuchets) in its account of the [[siege of Tortosa (808\u2013809)]].{{sfn|Noble|2009|p=241 n.73}} In 1173, the [[Republic of Pisa]] tried to capture an island castle with traction trebuchet on galleys.{{sfn|Purton|2009|p=291}} Traction trebuchets were also used in India.{{sfn|Purton|2009|p=366}}\n\n{{quotation|The catapult, the account of which has been translated from the Greek several times, was quadrangular, with a wide base but narrowing towards the top, using large iron rollers to which were fixed timber beams "similar to the beams of big houses", having at the back a sling, and at the front thick cables, enabling the arm to be raised and lowered, and which threw "enormous blocks into the air with a terrifying noise".{{sfn|Purton|2009|p=30}}|Peter Purton}}\n\nThe traction trebuchet was most efficient as an anti-personnel weapon, used in a supportive position alongside archers and slingers. Most accounts of traction trebuchets describe them as light artillery weapons while actual penetration of defenses was the result of mining or siege towers.{{sfn|Fulton|2018|p=24}} At the [[Siege of Kamacha]] in 766, Byzantine defenders used wooden cover to protect themselves from the enemy artillery while inflicting casualties with their own stone throwers. [[Michael the Syrian]] noted that at the siege of Balis in 823 it was the defenders that suffered from bombardment rather than the fortifications. At the siege of [[\u00c7ak\u0131rh\u00fcy\u00fck, Besni|Kaysum]], [[Abdallah ibn Tahir al-Khurasani]] used artillery to damage houses in the town. The [[Sack of Amorium]] in 838 saw the use of traction trebuchets to drive away defenders and destroy wooden defenses. At the siege of [[Marand]] in 848, traction trebuchets were used, "reportedly killing 100 and wounding 400 on each side during the eight-month siege."{{sfn|Fulton|2018|p=22}} During the [[Abbasid civil war (865\u2013866)|siege of Baghdad]] in 865, defensive artillery were responsible for repelling an attack on the city gate while traction trebuchets on boats claimed a hundred of the defenders' lives.{{sfn|Fulton|2018|p=22-23}}\n\nSome exceptionally large and powerful traction trebuchets have been described during the 11th century or later. At the [[Siege of Manzikert (1054)]], the [[Seljuks]]' initial siege artillery was countered by the defenders' own, which shot stones at the besieging machine. In response, the Seljuks constructed another one requiring 400 men to pull and threw stones weighing 20 kg. A breach was created on the first shot but the machine was burnt down by the defenders. According to [[Matthew of Edessa]], this machine weighed 3,400 kg and caused a number of casualties to the city's defenders.{{sfn|Fulton|2018|p=24}} [[Ibn al-Adim]] describes a traction trebuchet capable of throwing a man in 1089.{{sfn|Fulton|2018|p=25}} At the siege of [[Hai Prefecture|Haizhou]] in 1161, a traction trebuchet was reported to have had a range of 200 paces (over 400 meters).{{sfn|Needham|1994|p=215}}\n\nWest of China, the traction trebuchet remained the primary siege engine until the 12th century when it was replaced by the counterweight trebuchet.{{sfn|Purton|2009|p=29}} In China the traction trebuchet was the primary siege engine until the counterweight trebuchet was introduced during the [[Mongol conquest of the Song dynasty]] in the 13th century.<ref name="Citiy of Heavenly Tranquility">{{cite book|url=https://books.google.com/books?id=UOiGAAAAMAAJ&q=xianyang+foreign+engineers+persia+mangonels+catapults|title=City of heavenly tranquility: Beijing in the history of China|author=Jasper Becker|year=2008|publisher=Oxford University Press|edition=illustrated|isbn=978-0195309973|page=64|access-date=2010-10-28}}</ref>\n\n<gallery class="center" widths="180" heights="180">\nFile:Five whirlwind trebuchets wjzy.jpg|Five whirlwind trebuchets from the ''[[Wujing Zongyao]]''\nFile:Hudunpao-wujingzongyao.jpg|Crouching tiger trebuchet from the ''[[Wujing Zongyao]]''\nFile:SiJiao Pao-t1.jpg|S\u00ecji\u01ceo "Four Footed" traction trebuchet from the ''[[Wujing Zongyao]]''\nImage:Songrivership3.jpg|Traction trebuchet on a [[Song Dynasty]] warship from the ''[[Wujing Zongyao]]\nFile:Liber3.jpg|12th-century depiction of a traction trebuchet (also called a perrier) next to a staff slinger\nFile:Byzantine Trebuchet Skylintzes.jpg|Early 12th-century Sicilian-Byzantine depiction of a traction trebuchet\n</gallery>\n\n [[File:1187 \u0645\u0642\u0630\u0627\u0641.jpg|thumb|The earliest known depiction of a counterweight trebuchet, by Mardi ibn Ali al-Tarsusi, c. 1187]]\n[[File:DiezAlbumsFallOfBaghdad b.jpg|thumb|Depiction of the [[Siege of Baghdad (1258)]] with a counterweight trebuchet on the left, from the ''[[Jami' al-tawarikh]]'', 14th century ]]\n[[File:Juda-makabejsky-utok-na-akru-alpska-bible.jpg|thumb|Counterweight trebuchet, 1430]]\nThe counterweight trebuchet has been described as the "most powerful weapon of the Middle Ages".{{sfn|Purton|2009|p=382}} \n\nThe earliest known description and illustration of a counterweight trebuchet comes from a commentary on the conquests of [[Saladin]] by [[Mardi ibn Ali al-Tarsusi]] in 1187.<ref name="Bradbury 1992">{{cite book |last= Bradbury |first= Jim |title= The Medieval Siege |publisher= The Boydell Press |year= 1992 |isbn= 978-0-85115-312-4}}</ref><ref>{{cite web|url=http://www.historynet.com/weaponry-the-trebuchet.htm |title=Arms and Men: The Trebuchet |date=5 September 2006 |publisher=Historynet.com |access-date=2016-08-29 }}</ref> However cases for the existence of both European and Muslim counterweight trebuchets prior to 1187 have been made. In 1090, Khalaf ibn Mula'ib threw out a man from the citadel in [[Salamiya]] with a machine and in the early 12th century, Muslim siege engines were able to breach [[Crusades|crusader]] fortifications. David Nicolle argues that these events could have only been possible with the use of counterweight trebuchets.{{sfn|Nicolle|2003|p=16}}\n\nPaul E. Chevedden argues that counterweight trebuchets appeared prior to 1187 in Europe based on what might have been counterweight trebuchets in earlier sources. The 12th-century [[Byzantine]] historian [[Niketas Choniates]] may have been referring to a counterweight trebuchet when he described one equipped with a [[windlass]], which is only useful to counterweight machines, at the siege of Zevgminon in 1165.<ref>{{harvnb|Chevedden|2000|p=86}}</ref> At the [[siege of Nicaea]] in 1097 the Byzantine emperor [[Alexios I Komnenos]] reportedly invented new pieces of heavy artillery which deviated from the conventional design and made a deep impression on everyone.<ref>{{harvnb|Chevedden|2000|pp=76\u201386; 110f.}}</ref> Possible references to counterweight trebuchets also appear for the [[Venetian Crusade#Siege of Tyre|second siege of Tyre in 1124]], where the crusaders reportedly made use of "great trebuchets".<ref>{{harvnb|Chevedden|2000|p=92}}</ref> Chevedden argues that given the references to new and better trebuchets that by the 1120\u201330s, the counterweight trebuchet was being used in a variety of places by different peoples such as the crusader states, the [[Norman Kingdom of Sicily|Normans of Sicily]] and the [[Seljuks]].<ref name="Chevedden 2000, 104f.">{{harvnb|Chevedden|2000|pp=104f.}}</ref>\n\nThe earliest solid reference to a "trebuchet" in European sources dates to the siege of [[Castelnuovo Bocca d'Adda]] in 1199. However it is unclear if this referred to counterweight trebuchets since the author did not specify what engine was used and described the machine as fairly light.{{sfn|Fulton|2018|p=33}} They may have been used in [[Germany]] from around 1205. Only in the late 1210s do references to "trebuchet", describing more powerful engines and different components, more closely align with the features of a counterweight trebuchet. Some of these more powerful engines may have just been traction trebuchets, as one was described being pulled by ten thousand. At the [[Siege of Toulouse (1217\u20131218)]], ''trabuquets'' were mentioned to have been deployed,{{sfn|Fulton|2016|p=35}} but the siege engine depicted at the tomb of [[Simon de Montfort, 5th Earl of Leicester|Simon de Montfort]], who was killed by artillery at the siege, is a traction trebuchet.{{sfn|Fulton|2016|p=380}}<ref>https://jaanmarss.planet.ee/juhendid/Mehaanilised_kaugrelvad_keskajal/andmebaas/Russell%20Miners/htt01.html</ref><ref>{{Cite web|url=https://www.midi-france.info/medievalwarfare/121343_perriers.htm|title = Medieval Warfare during the Cathar Crusades}}</ref> Though soon after, clear evidence of counterweight machines appeared. According to the ''[[Song of the Albigensian Crusade]]'', the defenders "ran to the ropes and wound the trebuchets," and to shoot the machine, they "then released their ropes."{{sfn|Fulton|2018|p=34}} They were used in [[England]] at least by 1217 and in [[Iberia]] shortly after 1218. By the 1230s the counterweight trebuchet was a common item in siege warfare.{{sfn|Purton|2009|p=387}} Despite the lack of clearly definable terms in the late 12th and early 13th centuries, it is likely that both Muslims and Europeans already had working knowledge of the counterweight trebuchet beforehand. By the time of the [[Third Crusade]] (1189\u20131192), both sides seemed well acquainted with the enemy's siege weapons, which "appear to have been remarkably similar."{{sfn|Fulton|2018|p=36}}\n\nCounterweight trebuchets do not appear with certainty in Chinese historical records until about 1268. Prior to 1268, the counterweight trebuchet may have been used in 1232 by the [[Jin dynasty (1115\u20131234)|Jurchen Jin]] commander Qiang Shen. Qiang invented a device called the "Arresting Trebuchet" which only needed a few men to work it, and could hurl great stones more than a hundred paces, further than even the strongest traction trebuchet. However no other details on the machine are given. Qiang died the following year and no further references to the Arresting Trebuchet appear.{{sfn|Liang|2006}}{{sfn|Needham|1994|p=218}} The earliest definite mention of the counterweight trebuchet in China was in 1268, when the Mongols laid siege to Fancheng and Xiangyang. After failing to take the twin cities of Fancheng and Xiangyang for several years, collectively known as the [[Battle of Xiangyang|siege of Fancheng and Xiangyang]], the [[Mongol]] army brought in two Persian engineers to build hinged counterweight trebuchets. Known as the Huihui trebuchet (\u56de\u56de\u7832, where "[[Hui people|huihui]]" is a loose slang referring to any Muslims), or Xiangyang trebuchet (\u8944\u967d\u7832) because they were first encountered in that battle. [[Ismail (mangonel expert)|Ismail]] and [[Al al-Din|Al-aud-Din]] travelled to South China from [[Iraq]] and built trebuchets for the siege.<ref>{{cite book|url=https://books.google.com/books?id=UOiGAAAAMAAJ&q=xianyang+foreign+engineers+persia+mangonels+catapults|title=City of heavenly tranquility: Beijing in the history of China|author=Jasper Becker|year=2008|publisher=Oxford University Press|edition=illustrated|isbn=978-0195309973|page=64|access-date=2010-10-28}}</ref> Chinese and Muslim engineers operated artillery and siege engines for the Mongol armies.<ref>{{cite book|url=https://books.google.com/books?id=CHzGvqRbV_IC&q=chinese+engines+artillery+chinese+muslim+engineers&pg=PA282|title=The Empire of the Steppes: A History of Central Asia|author=Ren\u00e9 Grousset|year=1970|publisher=Rutgers University Press|edition=reprint|isbn=978-0813513041|page=283|access-date=2010-10-28}}</ref> By 1283, counterweight trebuchets were also used in Southeast Asia by the [[Chams]] against the [[Yuan dynasty]].{{sfn|Purton|2009|p=201}}\n\n{{quotation|The design of the Muslim trebuchets came originally from the Muslim countries, and they were more powerful than ordinary trebuchets. In the case of the largest ones, the wooden framework stood above a hole in the ground. The projectiles were several feet in diameter, and when they fell to the earth they made a hole three or four feet deep. when [the artillerists] wanted to hurl them to a great range, they added weight [to the counterpoise] and set it further back [on the arm] when they needed only a shorter distance, they set it forward, nearer [the fulcrum].{{sfn|Needham|1994|p=221}}|Zheng Sixiao}}\n\nWhile some historians have described the counterweight trebuchet as a type of medieval super weapon, other historians have urged caution in overemphasizing its destructive capability. On the side of the counterweight engine as a medieval military revolution, historians such as Sydney Toy, Paul Chevedden, and Hugh Kennedy consider its power to have caused significant changes in medieval warfare. This line of thought suggests that rams were abandoned due to the effectiveness of the counterweight trebuchet, which was capable of reducing "any fortress to rubble."{{sfn|Fulton|2018|p=324}} Accordingly, traditional fortifications became obsolete and had to be improved with new architectural structures to support defensive counterweight trebuchets. On the side of caution, historians such as John France, Christopher Marshall, and Michael Fulton emphasize the still considerable difficulty of reducing fortifications with siege artillery. Examples of the failure of siege artillery include the lack of evidence that artillery ever threatened the defenses of [[Kerak Castle]] between 1170 and 1188.{{sfn|Fulton|2018|p=326}} Marshall maintains that "the methods of attack and defence remained largely the same through the thirteenth century as they had been during the twelfth."{{sfn|Fulton|2018|p=327}} Reservations on the counterweight trebuchet's destructive capability were expressed by Viollet-le-Duc, who "asserted that even counterweight-powered artillery could do little more than destroy crenellations, clear defenders from parapets and target the machines of the besieged."{{sfn|Fulton|2018|p=328}} \n\nIn spite of the evidence regarding increasingly powerful counterweight trebuchets during the 13th century, "it remains an important consideration that not one of these appears to have effected a breach that directly led to the fall of a stronghold."{{sfn|Fulton|2018|p=347}} In 1220, [[Al-Mu'azzam Isa]] laid siege to [[Atlit]] with a ''trabuculus'', three ''petrariae'', and four ''mangonelli'' but could not penetrate past the outer wall, which was soft but thick.{{sfn|Fulton|2018|p=218}} As late as the [[Siege of Acre (1291)]], where the [[Mamluk Sultanate]] fielded 72 or 92 trebuchets, including 14 or 15 counterweight trebuchets and the remaining traction types, they were never able to fulfill a breaching role.{{sfn|Fulton|2018|p=299}} The Mamluks entered the city by sapping the northeast corner of the outer wall.{{sfn|Fulton|2018|p=298}} Though stone projectiles of substantial size (~66kg) have been found at Acre, located near the site of the siege and likely used by the Mamluks, surviving walls of a 13th century Montmusard tower are no more than one meter thick.{{sfn|Fulton|2018|p=297-300}} There is no indication that the thickness of fortress walls increased exponentially rather than a modest increase of 0.5-1m between the 12th and 13th centuries.{{sfn|Fulton|2018|p=334-335}} The [[Templar of Tyre]] described the faster firing traction trebuchets as more dangerous to the defenders than the counterweight ones.{{sfn|Fulton|2018|p=293-295}} The Song dynasty described countermeasures against counterweight trebuchets that prevented them from damaging towers and houses: "an extraordinary method was invented of neutralising the effects of the enemy's trebuchets. Ropes of rice straw four inches thick and thirty-four feet long were joined together twenty at a time, draped on to the buildings from top to bottom, and covered with [wet] clay. Then neither the incendiary arrows, nor bombs [''huo pao''] from trebuchets, nor even stones of a hundred ''jun'' caused any damage to the towers and houses."{{sfn|Needham|1994|p=225}}\n\nThe counterweight trebuchet did not completely replace the traction trebuchet. Despite its greater range, counterweight trebuchets had to be constructed close to the site of the siege unlike traction trebuchets, which were smaller, lighter, cheaper, and easier to take apart and put back together again where necessary.{{sfn|Turnbull|2001|p=33}} The superiority of the counterweight trebuchet was not clear cut. Of this, the [[Hongwu Emperor]] stated in 1388: "The old type of trebuchet was really more convenient. If you have a hundred of those machines, then when you are ready to march, each wooden pole can be carried by only four men. Then when you reach your destination, you encircle the city, set them up, and start shooting!"{{sfn|Needham|1994|p=229}} The traction trebuchet continued to serve as an anti-personnel weapon. The Norwegian text of 1240, ''Speculum regale'', explicitly states this division of functions. Traction trebuchets were to be used for hitting people in undefended areas.{{sfn|Purton|2009|p=386}} At the Siege of Acre (1291), both traction and counterweight trebuchets were used. The traction trebuchets provided cover fire while the counterweight trebuchets destroyed the city's fortifications.{{sfn|Fulton|2018|p=295}}\n\n{{quotation|Rather than replace traction trebuchets, counterweight trebuchets supplemented them in a different role. Their slower shooting rate and greater mass made them more difficult to reposition, or even yaw, leaving few incentives to\nemploy a small counterweight engine rather than a comparable traction type. Although less accurate, traction trebuchets might be expected to achieve the same result, albeit with more shots, in a similar amount of time. Accordingly, it was only profitable to employ counterweight trebuchets if they were capable of harnessing noticeably more energy, allowing them to throw significantly larger stones or similarly sized stones greater distances.{{sfn|Fulton|2018|p=47}}|Michael S. Fulton}}\n\nThere is some evidence that the counterweight trebuchet could be transported, as shown in two 17th- and 18th-century Chinese illustrations, which are also the only Chinese depictions of counterweight trebuchets on land. According to Liang Jieming, the "illustration shows... its throwing arm disassembled, its counterweight locked with supporting braces, and prepped for transport and not in battle deployment."{{sfn|Liang|2006}} However according to Joseph Needham, the large tank in the middle was the counterweight, while the bulb at the end of the arm was for adjusting between fixed and swinging counterweights. Both Liang and Needham note that the illustrations are poorly drawn and confusing, leading to mislabeling.{{sfn|Needham|1986|p=223}}\n\nThe counterweight and traction trebuchets were phased out around the mid-15th century in favor of gunpowder weapons.{{sfn|Turnbull|2001|p=36}}{{sfn|Purton|2010|p=269}}\n<gallery widths="170" heights="180" class="center">\nFile:CrusadersThrowingHeadsOfMuslimsOverRamparts.jpg|13th-century depiction of crusaders hurling Muslim heads with counterweight trebuchets\nFile:Siege de Nic\u00e9e (1097).jpg|14th-century depiction of a counterweight trebuchet\nFile:DiezAlbumsFallOfBaghdad a.jpg|Conquest of Baghdad (1258), from the ''[[Jami' al-tawarikh]]'', 14th century \nFile:Ms.Thott.290.2\u00ba 016v.jpg|15th-century depiction of a counterweight trebuchet\nFile:Vier B\u00fccher der Rytterschafft p33.tif|16th-century depiction of a counterweight trebuchet\nFile:\u6b66\u5099\u5fd7 \u8305\u5143\u5100 \u660e\u671d \u7832 01.jpg|A Chinese counterweight trebuchet packed for transport, from the ''[[Wubei Zhi]]''{{sfn|Needham|1986|p=223}}\nFile:Imperial Encyclopaedia - Military Administration - pic062 - \u6a13\u8239\u5716.png|Early 18th-century depiction of a Chinese ship armed with three counterweight trebuchets\n</gallery>\n\n With the introduction of [[gunpowder]], the trebuchet began to lose its place as the siege engine of choice to the [[cannon]]. Trebuchets were still used both at the [[Siege of Burgos (1475)|siege of Burgos]] (1475\u20131476) and [[siege of Rhodes (1480)]]. One of the last recorded military uses was by [[Hern\u00e1n Cort\u00e9s]], at the 1521 [[Fall of Tenochtitlan|siege of the Aztec capital Tenochtitl\u00e1n]]. Accounts of the attack note that its use was motivated by the limited supply of gunpowder. The attempt was reportedly unsuccessful: the first projectile landed on the trebuchet itself, destroying it.<ref>{{harvnb|Chevedden|1995|p=5}}</ref>\n\nIn China, the last time trebuchets were seriously considered for military purposes was in 1480. Not much is heard of them afterwards.{{sfn|Needham|1994|p=229}}"}},
{"article_title": "Windows Media Player", "pageid": "43941", "revid": "1056695273", "timestamp": "2021-11-23T01:14:05Z", "history_paths": [["Windows Media Player --- Introduction ---", "History"], ["Windows Media Player --- Introduction ---", "Release history"]], "categories": ["1991 software", "macintosh media players", "macos media players", "microsoft software", "microsoft windows multimedia technology", "pocket pc software", "tag editors", "windows cd ripping software", "windows components", "windows media players", "windows mobile standard software"], "heading_tree": {"Windows Media Player --- Introduction ---": {"History": {}, "Features": {"Core playback and library functions": {}, "Visualizations": {}, "Format support": {"Windows Media Player Mobile": {}}, "Disc burning, ripping, and playback": {}, "Portable device sync": {}, "Enhanced playback features": {}, "Shell integration": {}, "Extensibility": {}, "Online features": {}, "Media streaming": {}, "Skin Mode": {}}, "Security issues": {}, "Other versions": {"Windows Mobile": {}, "Mac OS X": {}}, "European Commission case": {}, "Visualizations": {}, "Release history": {}, "See also": {}, "Footnotes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Windows Media Player --- Introduction ---|History": "[[File:Media Player v5.1 (Microsoft).jpg|thumb|Media Player 5]]\nThe first version of Windows Media Player appeared in 1991, when [[Windows 3.0]] with [[Windows 3.0#Windows_3.0_with_Multimedia_Extensions|Multimedia Extensions]] was released.<ref>{{cite web |url=http://support.microsoft.com/kb/32905 |title=Windows Version History |date=September 23, 2011 |work=Support |publisher=[[Microsoft]] |edition=4.0 |access-date=May 2, 2009 |archive-date=February 26, 2015 |archive-url=https://web.archive.org/web/20150226175544/http://support.microsoft.com/kb/32905 |url-status=live }}</ref> Originally called Media Player, this component was included with "Multimedia PC"-compatible machines but not available for retail sale. It was capable of playing <code>.mmm</code> animation files, and could be extended to support other formats.<ref>{{cite web | url=http://toastytech.com/guis/win3mme.html | title=Windows 3.0 with Multimedia Extensions | work=Toasty Tech | access-date=May 2, 2009 | first=Nathan | last=Lineback | archive-date=April 15, 2009 | archive-url=https://web.archive.org/web/20090415145059/http://toastytech.com/guis/win3mme.html | url-status=live }}</ref> It used [[Media Control Interface|MCI]] to handle media files. Being a component of Windows, Media Player shows the same version number as that of the version Windows with which it was included.\n\nMicrosoft continually produced new programs to play media files. In November of the following year, [[Video for Windows]] was introduced with the ability to play [[digital video]] files in an [[Audio Video Interleave|AVI]] [[Container format (digital)|container format]],<ref>{{cite web|url=http://www.pctechguide.com/45DigitalVideo_Video_for_Windows.htm|title=Video for Windows|access-date=May 2, 2009|publisher=PC Tech Guide|archive-date=April 10, 2009|archive-url=https://web.archive.org/web/20090410061809/http://www.pctechguide.com/45DigitalVideo_Video_for_Windows.htm|url-status=live}}</ref> with codec support for [[Run-length encoding|RLE]] and [[Video1]], and support for playing uncompressed files. [[Indeo]] 3.2 was added in a later release. Video for Windows was first available as a free add-on to [[Windows 3.1]], and later integrated into [[Windows 95]] and [[Windows NT 4.0]]. In 1995, Microsoft released [[ActiveMovie]] with DirectX Media SDK. ActiveMovie incorporates a new way of dealing with media files, and adds support for streaming media (which the original Media Player could not handle). In 1996, ActiveMovie was renamed [[DirectShow]].<ref>{{cite web\n|url=http://msdn.microsoft.com/en-us/magazine/cc301631.aspx |title=DirectShow: Core Media Technology in Windows XP Empowers You to Create Custom Audio/Video Processing Components |date=July 2002 |access-date=May 1, 2009 |work=MSDN Magazine |publisher=[[Microsoft]] |first1 = Michael |last1 = Blome |first2 = Mike |last2 = Wasson |url-status=dead |archive-url=https://web.archive.org/web/20080914214002/http://msdn.microsoft.com/en-us/magazine/cc301631.aspx |archive-date=September 14, 2008}}</ref> However, Media Player continued to come with Windows until Windows XP, in which it was officially renamed Windows Media Player v5.1.<ref><code>C:\\Windows\\system32\\myplay32.exe</code>. Windows XP. Microsoft Corporation.</ref> ("v5.1" is the version number of Windows XP.)\n\nIn 1999, Windows Media Player's versioning broke away from that of Windows itself. Windows Media Player 6.4 came as an out-of-band update for [[Windows 95]]-[[Windows 98|98]] and [[Windows NT 4.0]] that co-existed with Media Player and became a built-in component of [[Windows 2000]], [[Windows ME]] and [[Windows XP]] with an ''mplayer2.exe'' stub allowing to use this built-in instead of newer versions.<ref>{{cite web|url=http://support.microsoft.com/kb/224401/en-us|title=MPLAYER2.EXE Is Linked to Missing Export MSDXM.OCX|work=Support|publisher=[[Microsoft]]|date=April 25, 2006|access-date=February 13, 2015|url-status=dead|archive-url=https://web.archive.org/web/20070314210342/http://support.microsoft.com/kb/224401|archive-date=March 14, 2007}}</ref> Windows Media Player 7.0 and its successors also came in the same fashion, replacing each other but leaving Media Player and Windows Media Player 6.4 intact. [[Windows XP]] is the only operating system to have three different versions of Windows Media Player (v5.1, v6.4 and v8) side by side. All versions branded Windows Media Player (instead of simply Media Player) support DirectShow codecs. Windows Media Player version 7 was a large revamp, with a new user interface, visualizations and increased functionality. [[Windows Vista]], however, dropped older versions of Windows Media Player in favor of v11, which included the removal of the Windows Media Source Filter (DirectShow codec).\n\nIn 2004 Microsoft launched digital music store [[MSN Music]] for new Windows Media Player 10 to compete with Apple iTunes.<ref>{{Cite web |url=https://www.cnet.com/news/msn-music-to-offer-free-songs/ |title=MSN Music to offer free songs |access-date=2020-05-21 |archive-date=2020-09-21 |archive-url=https://web.archive.org/web/20200921074549/https://www.cnet.com/news/msn-music-to-offer-free-songs/ |url-status=live }}</ref><ref>{{Cite web |url=https://news.microsoft.com/2004/09/01/msn-launches-preview-release-of-music-download-service/ |title=MSN Launches Preview Release of Music Download Service |date=September 2004 |access-date=2020-05-21 |archive-date=2020-08-06 |archive-url=https://web.archive.org/web/20200806104528/https://news.microsoft.com/2004/09/01/msn-launches-preview-release-of-music-download-service/ |url-status=live }}</ref>\nHowever, MSN Music was discontinued already in 2006 with the launch of [[Zune]] music players.<ref>{{Cite web |url=https://www.neowin.net/news/msn-music-shutting-down-for-zune |title=MSN Music Shutting Down for Zune |access-date=2020-05-21 |archive-date=2020-08-13 |archive-url=https://web.archive.org/web/20200813090050/https://www.neowin.net/news/msn-music-shutting-down-for-zune |url-status=live }}</ref>\n\nBeginning with [[Windows Vista]], Windows Media Player supports the [[Media Foundation]] framework besides DirectShow; as such it plays certain types of media using Media Foundation as well as some types of media using DirectShow.<ref>{{cite web |url=http://msdn.microsoft.com/en-us/library/dd562786(VS.85).aspx |title=DSP Plug-in Packaging |publisher=[[Microsoft]] |work=[[MSDN]] |access-date=2010-04-08 |archive-date=2010-11-05 |archive-url=https://web.archive.org/web/20101105225512/http://msdn.microsoft.com/en-us/library/dd562786(VS.85).aspx |url-status=live }}</ref> Windows Media Player 12 was released with [[Windows 7]]. It included support for more media formats and added new features. With [[Windows 8]], however, the player did not receive an upgrade.\n\nOn April 16, 2012, Microsoft announced that Windows Media Player would not be included in [[Windows RT]], the line of Windows designed to run on ARM-based devices.<ref>{{cite web |url=http://windowsteamblog.com/windows/b/bloggingwindows/archive/2012/04/16/announcing-the-windows-8-editions.aspx |title=Windows Announcing the Windows 8 Editions |publisher=The Windows Blog |date=April 16, 2012 |first=Brandon |last=LeBlanc |url-status=dead |archive-url=https://web.archive.org/web/20120418070243/http://windowsteamblog.com/windows/b/bloggingwindows/archive/2012/04/16/announcing-the-windows-8-editions.aspx |archive-date=April 18, 2012}}</ref>", "Windows Media Player --- Introduction ---|Release history": "Prior to the release of Windows Media Player in Windows 98 Second Edition, separate programs, [[CD Player (Windows)|CD Player]], Deluxe CD Player, [[DVD Player (Windows)|DVD Player]] and [[Media Player (Microsoft)|Media Player]], were included in old versions of Microsoft Windows for playback of media files.\n\n{| class = "wikitable"\n|+ Windows Media Player versions<ref>{{cite web|title=Get Windows Media Player|url=http://windows.microsoft.com/en-us/windows/downloads/windows-media-player|work=Windows|publisher=[[Microsoft]]|access-date=November 5, 2011|url-status=dead|archive-url=https://web.archive.org/web/20100825061104/http://windows.microsoft.com/en-us/windows/downloads/windows-media-player|archive-date=August 25, 2010}}</ref>\n|-\n!Version !! Original release !! Included with !! Available for\n!\n|-\n! colspan="6" style="text-align:center; background:#ddf;" | [[Microsoft Windows]]\n|-\n|'''Windows Media Player 12'''|| July 22, 2009 || [[Windows 7]]<br />[[Windows 8]]<br />[[Windows 8.1]]<br />[[Windows 10]]<br />[[Windows 11]]<br /> [[Windows Server 2008 R2]]<br />[[Windows Server 2012]]<br />[[Windows Server 2012 R2]]<br />[[Windows Server 2016]]<br>[[Windows Server 2019]]<br>[[Windows Server 2022]] || {{N/A}}\n|[[File:Windows Media Player 12 live preview.png|220x220px]]\n|-\n|'''Windows Media Player 11'''|| October 18, 2006 || [[Windows Vista]]<br />[[Windows Server 2008]] || [[Windows XP]] (SP2+)<br />[[Windows XP x64 Edition]]\n|\n|-\n|'''Windows Media Player 10'''|| August 25, 2004 || [[Windows XP x64 Edition]]<br />[[Windows XP Media Center Edition 2005]]<br/>[[Windows Server 2003]] (SP1+) || [[Windows Server 2003]]<br />[[Windows XP]]<ref name="10 latest">{{cite web|title=MS09-037: Description of the security update for Windows Media Player: August 11, 2009|url=http://support.microsoft.com/kb/973540|work=Support|publisher=[[Microsoft]]|access-date=August 12, 2013|date=May 8, 2012|archive-date=September 21, 2013|archive-url=https://web.archive.org/web/20130921055220/http://support.microsoft.com/kb/973540|url-status=live}}</ref>\n|\n|-\n|'''Windows Media Player 9 Series'''|| October 3, 2002<ref>{{cite web|url=http://news.microsoft.com/2003/01/07/final-release-of-windows-media-9-series-starts-next-wave-of-digital-media/|title=Final Release of Windows Media 9 Series Starts Next Wave of Digital Media|date=January 7, 2003|work=News Center|publisher=[[Microsoft]]|access-date=September 29, 2015|archive-date=February 3, 2016|archive-url=https://web.archive.org/web/20160203222536/http://news.microsoft.com/2003/01/07/final-release-of-windows-media-9-series-starts-next-wave-of-digital-media/|url-status=live}}</ref> || [[Windows XP]] (SP2+)<br />[[Windows Server 2003]] (RTM) || [[Windows XP]]<br />[[Windows ME]]<br />[[Windows 2000]]<br />[[Windows 98]] SE<ref name=":0">{{Cite web|url=https://www.petri.com/download_windows_media_player_9|title=Download Windows Media Player 9|last=Petri|first=Daniel|date=2009-01-08|website=Petri|language=en-US|access-date=2019-02-12|archive-date=2019-02-13|archive-url=https://web.archive.org/web/20190213064409/https://www.petri.com/download_windows_media_player_9|url-status=live}}</ref>\n|\n|-\n|'''Windows Media Player for Windows XP''' (version 8) || August 24, 2001 || [[Windows XP]] (RTM & SP1) || {{N/A}}\n|\n|-\n|'''Windows Media Player 7.1'''|| May 16, 2001 || {{N/A}} || [[Windows ME]]<br />[[Windows 2000]]<br />[[Windows 98]]<ref name=":0" /><ref>{{Cite web|url=https://www.bumpersoft.com/Video-and-Audio/MP3-and-Audio/Audio-and-CD-Players/Windows-Media-Player-7-1-for-Windows-98-2000-and-Me-711.htm|title=Windows Media Player 7.1 for Windows 98, 2000, and Me 7.1 - BumperSoft|website=www.bumpersoft.com|language=en|access-date=2019-02-12|archive-date=2019-02-13|archive-url=https://web.archive.org/web/20190213123635/https://www.bumpersoft.com/Video-and-Audio/MP3-and-Audio/Audio-and-CD-Players/Windows-Media-Player-7-1-for-Windows-98-2000-and-Me-711.htm|url-status=live}}</ref>\n|\n|-\n|'''Windows Media Player 7.0'''|| June 19, 2000<ref>{{cite web |url=https://news.microsoft.com/2000/07/17/microsoft-windows-media-player-7-brings-click-and-play-digital-media-to-millions-around-the-globe/ |title=Microsoft Windows Media Player 7 Brings Click and Play Digital Media To Millions Around the Globe |work=News Center |publisher=[[Microsoft]] |date=July 17, 2000 |access-date=June 15, 2011 |archive-date=May 27, 2015 |archive-url=https://web.archive.org/web/20150527051557/http://news.microsoft.com/2000/07/17/microsoft-windows-media-player-7-brings-click-and-play-digital-media-to-millions-around-the-globe/ |url-status=live }}</ref> || [[Windows ME]] || [[Windows 2000]]<br />[[Windows 98]]\n|\n|-\n|'''Windows Media Player 6.4'''{{efn|Windows Media Player 6.4 was shipped side-by-side with later versions of WMP in Windows ME and Windows XP}} || April 29, 1999 || [[Windows 2000]]<br />[[Windows ME]] (hidden)<br />[[Windows XP]] (hidden)<br />[[Windows Server 2003]] (hidden)<br />[[Internet Explorer 5|Internet Explorer 5.01]]<br />[[Internet Explorer 5|Internet Explorer 5.5]]<br />[[Internet Explorer 6|Internet Explorer 6.0]] || [[Windows 98]]<br />[[Windows NT 4.0]]<br />[[Windows 95]]\n|\n|-\n|'''Windows Media Player 6.1'''\n|| October 1997 || [[Windows 98]] SE<br />[[Internet Explorer 5|Internet Explorer 5.0]] || [[Windows 98]] <br/ >[[Windows NT 4.0]]<br/ >[[Windows 95]] \n|\n|-\n|'''Microsoft Media Player 5.1''' || 2001 || [[Windows XP]] (hidden) || {{N/A}}\n|\n|-\n|'''Media Player 5.0''' || 1999 || [[Windows 2000]] (hidden) || {{N/A}}\n|\n|-\n|'''Media Player 4.9''' || 2000 || [[Windows ME]] (hidden) || {{N/A}}\n|\n|-\n|'''Media Player 4.1''' || 1998 || [[Windows 98]]<br />[[Windows 98 SE]] (hidden) || {{N/A}}\n|\n|-\n|'''Media Player 4.0''' || 1995 || [[Windows 95]]<br />[[Windows NT 4.0]]<br /> || {{N/A}}\n|\n|-\n|'''Media Player 3.51''' || 1995 || [[Windows NT 3.51]] || {{N/A}}\n|\n|-\n|'''Media Player 3.5''' || 1994 || [[Windows NT 3.5]] || {{N/A}}\n|\n|-\n|'''Media Player 3.15''' || 1992 || {{N/A}} || [[Windows 3.1]] with [[Video for Windows]]\n|\n|-\n|'''Media Player 3.1''' || 1992 || [[Windows 3.1]]<br />[[Windows NT 3.1]] || {{N/A}}\n|\n|-\n|'''Media Player 3.0''' || 1991 || {{N/A}} || [[Windows 3.0]] with Multimedia Extension\n|\n|-\n! colspan="6" style="text-align:center; background:#ddf;" | [[Windows Mobile]]\n|-\n|'''Windows Media Player 10.3 Mobile'''|| February 12, 2007 (Windows Mobile 6) || [[Windows Mobile 6.1]]<br />[[Windows Mobile 6]] || [[Windows Mobile 5.0]]\n|[[File:Windows Media Player 10 Mobile.png|267x267px]]\n|-\n|'''Windows Media Player 10.2 Mobile'''|| {{dunno}} || [[Windows Mobile 5.0]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 10.1 Mobile'''|| May 10, 2005 || [[Windows Mobile 5.0]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 10 Mobile'''|| October 12, 2004 || [[Windows Mobile 2003 SE]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 9.0.1'''|| March 24, 2004 || [[Windows Mobile 2003 SE]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 9 Series'''|| June 23, 2003 || [[Windows Mobile 2003]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 8.5'''|| October 11, 2002 || [[Pocket PC 2002]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 8.01'''|| July 2002 || [[Pocket PC 2002]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 8'''|| October 4, 2001 (Pocket PC) || [[Pocket PC 2002]]<br />[[Smartphone 2002]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 7.1'''|| May 21, 2001 || [[Pocket PC 2000]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 7'''|| December 12, 2000 || [[Pocket PC 2000]] || {{N/A}}\n|\n|-\n|'''Windows Media Player 1.2'''|| September 7, 2000 || Handheld PC 2000 || {{N/A}}\n|\n|-\n|'''Windows Media Player 1.1'''|| {{dunno}} || Palm-size PC CE 2.11 || {{N/A}}\n|\n|-\n|'''Windows Media Player'''|| April 19, 2000 || [[Windows Mobile#Pocket PC 2000|Pocket PC 2000]] || {{N/A}}\n|\n|-\n! colspan="6" style="text-align:center; background:#ddf;" | [[classic Mac OS|Mac]]\n|-\n|'''Windows Media Player 9 Series'''|| November 7, 2003 || {{N/A}} || [[Mac OS X]]\n|\n|-\n|'''Windows Media Player 7'''|| July 24, 2001 || [[Mac OS 9]] || [[Mac OS 8|Mac OS 8.x]]\n|\n|-\n|'''Windows Media Player 6.3'''|| July 17, 2000 || [[Mac OS 8]] || [[System 7|Mac OS 7.x]]\n|\n|-\n! colspan="6" style="text-align:center; background:#ddf;" | [[Solaris (operating system)|Solaris]]\n|-\n|'''Windows Media Player 6.3'''|| July 17, 2000 || {{N/A}} || [[Solaris (operating system)|Solaris]]\n|\n|}"}},
{"article_title": "Electroconvulsive therapy", "pageid": "44093", "revid": "1062748697", "timestamp": "2021-12-30T08:23:36Z", "history_paths": [["Electroconvulsive therapy --- Introduction ---", "History"]], "categories": ["electroconvulsive therapy", "human rights abuses", "human subject research in psychiatry", "psychiatry controversies", "neurotechnology", "physical psychiatric treatments", "treatment of bipolar disorder", "treatment of depression"], "heading_tree": {"Electroconvulsive therapy --- Introduction ---": {"Medical use": {"Major depressive disorder": {"Efficacy": {}, "Follow-up": {}}, "Catatonia": {}, "Mania": {}, "Schizophrenia": {}}, "Effects": {"Cognitive impairment": {}, "Effects on brain structure": {}, "Effects in pregnancy": {}, "Effects on the heart": {}}, "Procedure": {"Neuroimaging prior to ECT": {}, "Concurrent pharmacotherapy": {}, "Course": {}, "The team": {}, "Devices": {}}, "Mechanism of action": {}, "Use": {"United States": {}, "United Kingdom": {}, "China": {}}, "History": {}, "Society and culture": {"Controversy": {}, "Legal status": {"Informed consent": {}, "Involuntary ECT": {"United States": {}, "United Kingdom": {}}, "Regulation": {}}, "Public perception": {}, "Famous cases": {}, "Fictional examples": {}}, "Special populations": {"Sex difference": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Electroconvulsive therapy --- Introduction ---|History": "[[File:Bergonic chair.jpg|thumb|A ''Bergonic chair'', a device "for giving general electric treatment for psychological effect, in psycho-neurotic cases", according to original photo description. World War I era.]]\n{{Further|History of electroconvulsive therapy in the United Kingdom|History of electroconvulsive therapy in the United States}}\nAs early as the 16th century, agents to induce seizures were used to treat psychiatric conditions. In 1785, the therapeutic use of seizure induction was documented in the ''[[London Medical and Surgical Journal]]''.<ref name="Rudorfer" /><ref>[http://www.tiki-toki.com/timeline/entry/37146/A-History-of-Mental-Institutions-in-the-United-States/#vars!panel=403723! A History of Mental Institutions in the United States] which says electrostatic machines were used in 1773</ref> As to its earliest antecedents one doctor claims 1744 as the dawn of electricity's therapeutic use, as documented in the first issue of ''Electricity and Medicine''. Treatment and cure of [[Conversion disorder|hysterical blindness]] was documented eleven years later. [[Benjamin Franklin]] wrote that an electrostatic machine cured "a woman of hysterical fits." By 1801, [[James Lind (physician, born 1736)|James Lind]]<ref>{{Cite web|title=Lind, James (1736-1812) on JSTOR|url=https://plants.jstor.org/stable/10.5555/al.ap.person.bm000033179|access-date=2021-05-08|website=plants.jstor.org|doi=}}</ref> as well as [[Giovanni Aldini]] had used [[galvanism]] to treat patients suffering from various mental disorders.<ref>{{cite journal|last1=Parent|first1=Andre|title=Giovanni Aldini: from animal electricity to human brain stimulation|journal=Can J Neurol Sci|date=2004|volume=31|issue=4|pages=576\u201384|pmid=15595271|doi=10.1017/s0317167100003851|doi-access=free}}</ref> G.B.C. Duchenne, the mid-19th century "Father of Electrotherapy", said its use was integral to a neurological practice.<ref>{{cite journal |title=An Historical Review of Electro Convulsive Therapy |first1=Bruce A. M.D. |last1=Wright |url=http://jdc.jefferson.edu/cgi/viewcontent.cgi?article=1256&context=jeffjpsychiatry |journal=Jefferson Journal of Psychiatry |pages=66\u201374}}</ref>\n\nIn the second half of the 19th century, such efforts were frequent enough in British asylums as to make it notable.<ref>{{cite journal |journal=[[British Journal of Psychiatry]] |year=1988 |volume=153 |issue=2 | pages= 157\u2013162 |title=Electricity: A History of its use in the Treatment of Mental Illness in Britain During the Second Half of the 19th Century |first1=A. W. |last1=Beveridge |first2=E. B. |last2=Renvoize |url=http://www.breggin.com/ECT/ElctyHistoryUseTrtmntBritain.pdf |access-date=28 December 2014 | pmid = 3076490 | doi = 10.1192/bjp.153.2.157 }}</ref>\n\nConvulsive therapy was introduced in 1934 by Hungarian neuropsychiatrist [[Ladislas J. Meduna]] who, believing mistakenly that [[schizophrenia]] and [[epilepsy]] were antagonistic disorders, induced seizures first with [[camphor]] and then [[metrazol]] (cardiazol).<ref>{{cite journal | doi = 10.1177/0957154X9700802908 | last1 = Berrios | first1 = G E | year = 1997 | title = The scientific origins of electroconvulsive therapy | journal = History of Psychiatry | volume = 8 | issue = 29 pt 1| pages = 105\u2013119 | pmid = 11619203 | s2cid = 12121233 }}</ref><ref name="Fink-history">{{cite journal | last1 = Fink | first1 = M | year = 1984 | title = The origins of convulsive therapy | doi = 10.1176/ajp.141.9.1034 | journal = American Journal of Psychiatry | volume = 141 | issue = 9| pages = 1034\u201341 | pmid = 6147103 }}</ref> Meduna is thought to be the father of convulsive therapy.<ref name=Bolwig>{{cite journal|last=Bolwig|first=T.|title=How does electroconvulsive therapy work? Theories on its mechanism|journal=The Canadian Journal of Psychiatry|year=2011|volume=56|issue=1|pages=13\u201318|pmid=21324238|doi=10.1177/070674371105600104|doi-access=free}}</ref> In 1937, the first international meeting on schizophrenia and convulsive therapy was held in Switzerland by the Swiss psychiatrist Max M\u00fcller.<ref>Bangen, Hans: Geschichte der medikament\u00f6sen Therapie der Schizophrenie. Berlin 1992, {{ISBN|3-927408-82-4}}</ref> The proceedings were published in the ''[[American Journal of Psychiatry]]'' and, within three years, cardiazol convulsive therapy was being used worldwide.<ref name="Fink-history" /> Italian Professor of neuropsychiatry [[Ugo Cerletti]], who had been using electric shocks to produce seizures in animal experiments, and his assistant [[Lucio Bini]] at Sapienza University of Rome developed the idea of using electricity as a substitute for metrazol in convulsive therapy and, in 1938, experimented for the first time on a person affected by delusions. It was believed early on that inducing convulsions aided in helping those with severe schizophrenia but later found to be most useful with affective disorders such as depression. Cerletti had noted a shock to the head produced convulsions in dogs. The idea to use electroshock on humans came to Cerletti when he saw how pigs were given an electric shock before being butchered to put them in an anesthetized state.<ref name=Sabbatini>{{cite web|last=Sabbatini|first=R.|title=The history of shock therapy in psychiatry|url=http://www.cerebromente.org.br/n04/historia/shock_i.htm|access-date=2013-04-24}}</ref> Cerletti and Bini practiced until they felt they had the right parameters needed to have a successful human trial. Once they started trials on patients, they found that after 10-20 treatments the results were significant. Patients had much improved. A positive side effect to the treatment was [[retrograde amnesia]]. It was because of this side effect that patients could not remember the treatments and had no ill feelings toward it.<ref name="Sabbatini" /> ECT soon replaced metrazol therapy all over the world because it was cheaper, less frightening and more convenient.<ref>Cerletti, U (1956). "Electroshock therapy". In AM Sackler ''et al''. (eds) ''The Great Physiodynamic Therapies in Psychiatry: an historical appraisal.'' New York: Hoeber-Harper, 91\u2013120.</ref> Cerletti and Bini were nominated for a [[Nobel Prize]] but did not receive one. By 1940, the procedure was introduced to both England and the US. In Germany and Austria, it was promoted by [[Friedrich Meggendorfer]]. Through the 1940s and 1950s, the use of ECT became widespread. At the time the ECT device was patented and commercialized abroad, the two Italian inventors had competitive tensions that damaged their relationship.<ref>{{cite journal |last1=Sirgiovanni |first1=Elisabetta |last2=Aruta |first2=Alessandro |title=From the Madhouse to the Docu-Museum: The Enigma Surrounding the Cerletti-Bini ECT Apparatus Prototype |journal=Nuncius |date=April 23, 2020 |volume=35 |issue=1 |page=141 |doi=10.1163/18253911-03501013|s2cid=218991982 }}</ref> In the 1960s, despite a climate of condemnation, the original Cerletti-Bini ECT apparatus prototype was hotly contended by scientific museums between Italy and the USA.<ref name=":2">Sirgiovanni, E, Aruta, A (2020) "The Electroshock Triangle: Disputes about the ECT Apparatus Prototype and its Display in the 1960s, History of Psychiatry. First Published April 20, 2020: https://doi.org/10.1177/0957154X20916147.</ref> The ECT apparatus prototype is now owned and displayed by the Sapienza [[:it:Museo di storia della medicina|Museum of the History of Medicine]] in Rome.<ref name=":2" />\n\nIn the early 1940s, in an attempt to reduce the memory disturbance and confusion associated with treatment, two modifications were introduced: the use of unilateral electrode placement and the replacement of sinusoidal current with brief pulse. It took many years for brief-pulse equipment to be widely adopted.<ref name="Kiloh">Kiloh, LG, Smith, JS, Johnson, GF (1988). ''Physical Treatments in Psychiatry''. Melbourne: Blackwell Scientific Publications, 190\u2013208. {{ISBN|0-86793-112-4}}</ref>  In the 1940s and early 1950s ECT, was usually given in "unmodified" form, without muscle relaxants, and the seizure resulted in a full-scale convulsion. A rare but serious complication of unmodified ECT was fracture or dislocation of the long bones. In the 1940s, psychiatrists began to experiment with [[curare]], the muscle-paralysing South American poison, in order to modify the convulsions. The introduction of [[suxamethonium]] (succinylcholine), a safer synthetic alternative to curare, in 1951 led to the more widespread use of "modified" ECT. A short-acting anesthetic was usually given in addition to the muscle relaxant in order to spare patients the terrifying feeling of suffocation that can be experienced with muscle relaxants.<ref name="Kiloh"/>\n\nThe steady growth of antidepressant use along with negative depictions of ECT in the mass media led to a marked decline in the use of ECT during the 1950s to the 1970s. The [[Surgeon General of the United States|Surgeon General]] stated there were problems with electroshock therapy in the initial years before anesthesia was routinely given, and that "these now-antiquated practices contributed to the negative portrayal of ECT in the popular media."<ref name="erica goode">\n{{Cite news\n|url=https://query.nytimes.com/gst/fullpage.html?sec=health&res=9805E1DD1431F935A35753C1A96F958260\n|title=Federal Report Praising Electroshock Stirs Uproar\n|last=Goode\n|first=Erica\n|date=1999-10-06\n|access-date=2008-01-01\n|newspaper=The New York Times\n}}\n</ref> ''The New York Times'' described the public's negative perception of ECT as being caused mainly by one movie: "For Big Nurse in ''[[One Flew Over the Cuckoo's Nest (film)|One Flew Over the Cuckoo's Nest]],'' it was a tool of terror, and, in the public mind, ''shock therapy'' has retained the tarnished image given it by Ken Kesey's novel: dangerous, inhumane and overused".<ref name="Goleman 1990">{{cite news|url=https://query.nytimes.com/gst/fullpage.html?res=9C0CE0D81F3EF931A3575BC0A966958260&pagewanted=all|title=The Quiet Comeback of Electroshock Therapy|last=Goleman|first=Daniel|date=1990-08-02|work=The New York Times|page=B5|access-date=2008-01-01}}</ref>\n\nIn 1976, Dr. Blatchley demonstrated the effectiveness of his constant current, brief pulse device ECT. This device eventually largely replaced earlier devices because of the reduction in cognitive side effects, although as of 2012 some ECT clinics still were using sine-wave devices.<ref name=LeiknesWWrev2012>Leiknes KA, et al (2012) [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3381633/ Contemporary use and practice of electroconvulsive therapy worldwide.]  Brain Behav. 2(3):283-344</ref> The 1970s saw the publication of the first [[American Psychiatric Association]] (APA) task force report on electroconvulsive therapy (to be followed by further reports in 1990 and 2001). The report endorsed the use of ECT in the treatment of depression. The decade also saw criticism of ECT.<ref>See Friedberg, J (1977). "Shock treatment, brain damage, and memory loss: a neurological perspective". ''American Journal of Psychiatry'' '''134''':1010\u20131014; and Breggin, PR (1979) ''Electroshock: its brain-disabling effects''. New York: Springer</ref>  Specifically, critics pointed to shortcomings such as noted side effects, the procedure being used as a form of abuse, and uneven application of ECT. The use of ECT declined until the 1980s, "when use began to increase amid growing awareness of its benefits and cost-effectiveness for treating severe depression".<ref name="erica goode"/> In 1985, the [[National Institute of Mental Health]] and [[National Institutes of Health]] convened a consensus development conference on ECT and concluded that, while ECT was the most controversial treatment in psychiatry and had significant side-effects, it had been shown to be effective for a narrow range of severe psychiatric disorders.<ref>{{cite journal | last1 = Blaine | first1 = JD | last2 = Clark | first2 = SM | year = 1986 | title = Report of the NIMH\u2013NIH consensus development conference on Electroconvulsive therapy | journal = Psychopharmacology Bulletin | volume = 22 | issue = 2| pages = 445\u2013452 | pmid = 3774937 }}</ref>\n\nBecause of the backlash noted previously, national institutions reviewed past practices and set new standards. In 1978, the American Psychiatric Association released its first task force report in which new standards for [[consent]] were introduced and the use of unilateral electrode placement was recommended. The 1985 NIMH Consensus Conference confirmed the therapeutic role of ECT in certain circumstances. The American Psychiatric Association released its second task force report in 1990 where specific details on the delivery, education, and training of ECT were documented. Finally, in 2001 the American Psychiatric Association released its latest task force report.<ref name="APA2001guideline"/> This report emphasizes the importance of [[informed consent]], and the expanded role that the procedure has in modern medicine. By 2017, ECT was routinely covered by insurance companies for providing the "biggest bang for the buck" for otherwise intractable cases of severe mental illness, was receiving favorable media coverage, and was being provided in regional medical centers.<ref name="ECT Provided in Boise">{{Cite web |url=http://www.idahostatesman.com/news/business/article133259549.html |title=This mental health treatment isn't barbaric, it 'totally changed my life'  |last=Dutton |first=Audrey |date=2017-02-18}}</ref>\n\nThough ECT use declined with the advent of modern antidepressants, there has been a resurgence of ECT with new modern technologies and techniques.<ref>{{Cite web | url=https://www.mdedge.com/psychiatry/article/64868/bipolar-disorder/electroconvulsive-therapy-how-modern-techniques-improve | title=Electroconvulsive therapy: How modern techniques improve patient outcomes}}</ref> Modern shock voltage is given for a shorter duration of 0.5 milliseconds where conventional brief pulse is 1.5 milliseconds.<ref>{{cite journal | doi = 10.5348/ijcri-2012-07-147-CR-8 | volume=3 | issue = 7 | title=A case of schizophrenia successfully treated by m-ECT using 'long' brief pulse | year=2012 | journal=International Journal of Case Reports and Images | page=30 |vauthors=Hiroaki I, Hirohiko H, Masanari I |doi-access=free }}</ref>"}},
{"article_title": "Process (computing)", "pageid": "45178", "revid": "1061673304", "timestamp": "2021-12-23T04:53:48Z", "history_paths": [["Process (computing) --- Introduction ---", "History"]], "categories": ["process (computing)", "concurrent computing", "operating system technology"], "heading_tree": {"Process (computing) --- Introduction ---": {"Representation": {}, "Multitasking and process management": {"Process states": {}}, "Inter-process communication": {}, "History": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Process (computing) --- Introduction ---|History": "{{See also|History of operating systems}}\n\nBy the early 1960s, computer control software had evolved from [[monitor control software]], for example [[IBM 7090/94 IBSYS|IBSYS]], to [[executive control software]]. Over time, computers got faster while [[Time-sharing|computer time]] was still neither cheap nor fully utilized; such an environment made [[Computer multitasking#Multiprogramming|multiprogramming]] possible and necessary. Multiprogramming means that several programs run [[Concurrency (computer science)|concurrently]]. At first, more than one program ran on a single processor, as a result of underlying [[uniprocessor system|uniprocessor]] computer architecture, and they shared scarce and limited hardware resources; consequently, the concurrency was of a ''serial'' nature. On later systems with [[Multiprocessing|multiple processors]], multiple programs may run concurrently in ''[[Parallel computing|parallel]]''.\n\nPrograms consist of sequences of instructions for processors. A single processor can run only one instruction at a time: it is impossible to run more programs at the same time. A program might need some [[System resource|resource]], such as an input device, which has a large delay, or a program might start some slow operation, such as sending output to a printer. This would lead to processor being "idle" (unused). To keep the processor busy at all times, the execution of such a program is halted and the operating system switches the processor to run another program. To the user, it will appear that the programs run at the same time (hence the term "parallel").\n\nShortly thereafter, the notion of a "program" was expanded to the notion of an "executing program and its context". The concept of a process was born, which also became necessary with the invention of [[Reentrancy (computing)|re-entrant code]]. [[Thread (computer science)|Threads]] came somewhat later. However, with the advent of concepts such as [[time-sharing]], [[computer network]]s, and multiple-CPU [[shared memory]] computers, the old "multiprogramming" gave way to true [[Computer multitasking|multitasking]], multiprocessing and, later, [[Thread (computing)#Multithreading|multithreading]]."}},
{"article_title": "Biomimetics", "pageid": "45784", "revid": "1060929507", "timestamp": "2021-12-18T15:36:32Z", "history_paths": [["Biomimetics --- Introduction ---", "History"]], "categories": ["evolutionary biology", "biotechnology", "biomimetics", "bioinformatics", "biological engineering", "biophysics", "industrial ecology", "bionics", "water conservation", "renewable energy", "sustainable transport"], "heading_tree": {"Biomimetics --- Introduction ---": {"History": {}, "Bio-inspired technologies": {"Locomotion": {}, "Biomimetic architecture": {"Characteristics": {}, "Procedures": {}, "Examples": {}}, "Structural materials": {}, "Neuronal computers": {}, "Self healing-materials": {}, "Surfaces": {}, "Adhesion": {"Wet adhesion": {}, "Dry adhesion": {}}, "Optics": {"Inspiration from fruits and plants": {}, "Inspiration from animals": {}}, "Agricultural systems": {}, "Other uses": {}}, "Other technologies": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Biomimetics --- Introduction ---|History": "One of the early examples of  biomimicry was the study of [[birds]] to enable [[human flight]]. Although never successful in creating a "flying machine", [[Leonardo da Vinci]] (1452\u20131519) was a keen observer of the anatomy and flight of birds, and made numerous notes and sketches on his observations as well as sketches of "flying machines".<ref name="Romei 2008 56">{{Cite book | last=Romei | first=Francesca | title=Leonardo Da Vinci | publisher=The Oliver Press  | year=2008 | page=56 | isbn=978-1-934545-00-3}}</ref> The [[Wright Brothers]], who succeeded in flying the first heavier-than-air aircraft in 1903, allegedly derived inspiration from observations of pigeons in flight.<ref>Compare: {{Cite book | last=Howard | first=Fred | title=Wilbur and Orville: A Biography of the Wright Brothers | publisher=Dober Publications | year=1998 | page=33 | isbn=978-0-486-40297-0 | quote = According to Wilbur, he and his brother discovered the birds' method of lateral control one day while observing a flight of pigeons. [...] 'Although we intently watched birds fly in a hope of learning something from them,' [Orville] wrote in 1941, 'I cannot think of anything that was first learned in that way.'}}</ref>\n\n[[File:Leonardo Design for a Flying Machine, c. 1488.jpg|thumb|200px|[[Leonardo da Vinci]]'s [[Science and inventions of Leonardo da Vinci#Flight|design for a flying machine]] with wings based closely upon the structure of bat wings]]\n\nDuring the 1950s the American [[biophysicist]] and [[polymath]] [[Otto Schmitt]] developed the concept of "biomimetics".<ref name="Vincent2006">{{cite journal |last= Vincent |first= Julian F.V. |author2= Bogatyreva, Olga A. |author3= Bogatyrev, Nikolaj R. |author4= Bowyer, Adrian |author5= Pahl, Anja-Karina |title= Biomimetics: its practice and theory |journal= Journal of the Royal Society Interface |date= 21 August 2006|volume= 3|issue= 9|pages= 471\u2013482|doi= 10.1098/rsif.2006.0127 |pmid= 16849244 |pmc= 1664643}}</ref> During his doctoral research he developed the [[Schmitt trigger]] by studying the nerves in squid, attempting to engineer a device that replicated the biological system of [[nerve impulse|nerve propagation]].<ref>{{cite web |title= Otto H. Schmitt, Como People of the Past |url= https://sites.google.com/a/comogreenvillage.info/como-history/home/people-of-the-past-documents/como-people-of-the-past/otto-h-schmitt |publisher= Connie Sullivan, Como History Article |quote=He developed the trigger by studying the nerves in squid and trying to engineer a device that replicated the natural system by which squid nerves propagate.}}</ref> He continued to focus on devices that mimic natural systems and by 1957 he had perceived a converse to the standard view of [[biophysics]] at that time, a view he would come to call biomimetics.<ref name="Vincent2006" />\n\n{{Quote|Biophysics is not so much a subject matter as it is a point of view. It is an approach to problems of biological science utilizing the theory and technology of the physical sciences. Conversely, biophysics is also a biologist's approach to problems of physical science and engineering, although this aspect has largely been neglected.|Otto Herbert Schmitt|''In Appreciation, A Lifetime of Connections''<ref>''In Appreciation, A Lifetime of Connections'': Otto Herbert Schmitt, 1913 - 1998</ref>}}\n\nIn 1960 [[Jack E. Steele]] coined a similar term, ''[[bionics]]'', at Wright-Patterson Air Force Base in Dayton, Ohio, where Otto Schmitt also worked. Steele defined bionics as "the science of systems which have some function copied from nature, or which represent characteristics of natural systems or their analogues".<ref name="McCarty">Mary McCarty. [https://web.archive.org/web/20110604025951/http://www.daytondailynews.com/o/content/oh/story/opinions/columns/2009/01/29/ddn012909mary.html?cxntlid=inform_sr "Life of bionics founder a fine adventure"]. ''Dayton Daily News'', 29 January 2009.</ref><ref name="vincent-2009">{{cite journal |last= Vincent|first= Julian F. V. |title= Biomimetics \u2014 a review|journal= Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine |date= November 2009|volume= 223 |issue= 8 |pages= 919\u2013939 |doi= 10.1243/09544119JEIM561|pmid= 20092091 |s2cid= 21895651 }}</ref> During a later meeting in 1963 Schmitt stated,\n\n{{Quote|Let us consider what bionics has come to mean operationally and what it or some word like it (I prefer biomimetics) ought to mean in order to make good use of the technical skills of scientists specializing, or rather, I should say, despecializing into this area of research.|Otto Herbert Schmitt|In Appreciation, A Lifetime of Connections: Otto Herbert Schmitt, 1913 - 1998}}\n\nIn 1969, Schmitt used the term "biomimetic" in the title one of his papers,<ref>Schmitt O. Third Int. Biophysics Congress. 1969. Some interesting and useful biomimetic transforms. p. 297.</ref> and by 1974 it had found its way into [[Webster's Dictionary]], bionics entered the same dictionary earlier in 1960 as "a science concerned with the application of data about the functioning of biological systems to the solution of engineering problems". Bionic took on a different connotation when [[Martin Caidin]] referenced Jack Steele and his work in the novel ''[[Cyborg (novel)|Cyborg]]'' which later resulted in the 1974 television series ''[[The Six Million Dollar Man]]'' and its spin-offs. The term bionic then became associated with "the use of electronically operated artificial body parts" and "having ordinary human powers increased by or as if by the aid of such devices".<ref>{{cite book |title=Compact Oxford English Dictionary |year=2008 |isbn=978-0-19-953296-4|last1=Soanes |first1=Catherine |last2=Hawker |first2=Sara }}</ref> Because the term ''bionic'' took on the implication of supernatural strength, the scientific community in [[english language|English]] speaking countries largely abandoned it.<ref>{{Cite journal | last =Vincent | first =JFV | title = Biomimetics \u2014 a review| journal =Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine | volume =223 | issue=8| pages=919\u2013939 | year=2009 | doi =10.1243/09544119JEIM561| pmid =20092091 | s2cid =21895651 }}</ref>\n\nThe term ''biomimicry'' appeared as early as 1982.<ref>{{Cite journal | last=Merrill | first=Connie Lange | title=Biomimicry of the Dioxygen Active Site in the Copper Proteins Hemocyanin and Cytochrome Oxidase  | location=Rice University  | year=1982  }}</ref> Biomimicry was popularized by scientist and author [[Janine Benyus]] in her 1997 book ''Biomimicry: Innovation Inspired by Nature''. Biomimicry is defined in the book as a "new science that studies nature's models and then imitates or takes inspiration from these designs and processes to solve human problems". Benyus suggests looking to Nature as a "Model, Measure, and Mentor" and emphasizes sustainability as an objective of biomimicry.<ref name="Benyus 1997">{{cite book |last=Benyus |first=Janine |title=Biomimicry: Innovation Inspired by Nature |year=1997 |publisher=[[William Morrow & Company]] |location=New York, USA |isbn=978-0-688-16099-9 |ref=Benyus97}}</ref>\n\nOne of the latest examples of biomimicry has been created by Johannes-Paul Fladerer and Ernst Kurzmann by the description of "managemANT".<ref>{{cite book |last1=Kurzmann |first1=Ernst |last2=Fladerer |first2=Johannes-Paul |title=ManagemANT Was Fach- und F\u00fchrungskr\u00e4fte von Ameisen lernen k\u00f6nnen |date=2017 |publisher=Frankfurter Allgemeine Buch |isbn=9783956012082 |edition=1. Auflage}}</ref> This term (a combination of the words "management" and "ant"), describes the usage of behavioural strategies of ants in economic and management strategies.<ref>{{cite book |last1=Fladerer |first1=Johannes-Paul |last2=Kurzmann |first2=Ernst |title=WISDOM OF THE MANY : how to create self -organisation and how to use collective... intelligence in companies and in society from mana. |date=November 2019 |publisher=BOOKS ON DEMAND |isbn=9783750422421}}</ref>"}},
{"article_title": "Subwoofer", "pageid": "45810", "revid": "1058204681", "timestamp": "2021-12-02T02:35:06Z", "history_paths": [["Subwoofer --- Introduction ---", "History"]], "categories": ["loudspeakers", "in-car entertainment", "audio engineering", "film and video technology", "bass (sound)", "loudspeaker technology", "audio hobbies"], "heading_tree": {"Subwoofer --- Introduction ---": {"History": {"1920s to 1950s precursors": {}, "1960s: first subwoofers": {}, "1970s to 1980s": {}, "1990s to 2010s": {}}, "Construction and features": {"Loudspeaker and enclosure design": {}, "Frequency range and frequency response": {}, "Amplification": {}, "Equalization": {}, "Phase control": {}, "Servo subwoofers": {}}, "Applications": {"Home audio": {}, "Car audio": {}, "Cinema sound": {}, "Sound reinforcement": {"Use in a full-range system": {}, "Aux-fed subwoofers": {}, "Directional bass": {"Vertical array": {}, "Rear delay array": {}, "End-fire array": {}, "Delay-shaded array": {}, "Directional enclosure": {}}}, "Variants": {}, "Enclosure designs": {}, "Bass instrument amplification": {}}, "Bass shakers": {}, "World record claims": {"Matterhorn": {}, "Royal Device custom installation": {}, "Concept Design 60-inch": {}, "MTX Jackhammer": {}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Subwoofer --- Introduction ---|History": "[[File:Infinity Servo Statik subwoofer.jpg|thumb|right|250px|View of the underside of the downward-firing [[Infinity Systems|Infinity]] Servo Statik 1, showing the size of the 18-inch (45 cm) custom-wound Cerwin Vega driver in relation to a can of Diet Coke, to show scale.]]\n\n From about 1900 to the 1950s, the "lowest frequency in practical use" in recordings, broadcasting and music playback was 100 Hz.<ref name="Fink, Robert 2018. p. 105">Fink, Robert. "Below 100 Hz: Towards a Musicology of Bass Culture". In ''The Relentless Pursuit of Tone: Timbre in Popular Music'', eds. Fink, Robert; Latour, Melinda; Wallmark, Zachary. Oxford University Press, 2018. p. 105</ref> When sound was developed for motion pictures, the basic RCA sound system was a single 8" speaker mounted in straight horn, an approach which was deemed unsatisfactory by Hollywood decisionmakers, who hired [[Western Electric]] engineers to develop a better speaker system.<ref name="ReferenceA">Eargle, John. M. ''The JBL Story \u2013 60 Years of Audio Innovation''.</ref> The early Western Electric experiments added a set of 18" drivers for the low end in a large, open-backed baffle (extending the range down to 50 Hz) and a high-frequency unit, but [[Metro-Goldwyn-Mayer|MGM]] was not pleased with the sound of the three-way system, as they had concerns about the delay between the different drivers.<ref name="ReferenceA"/>\n\nIn 1933, the head of MGM's sound department, [[Douglas Shearer]], worked with [[John Kenneth Hilliard|John Hilliard]] and [[James B. Lansing]] (who would later found [[Altec Lansing]] in 1941 and [[JBL (company)|JBL]] in 1946) to develop a new speaker system that used a two-way enclosure with a W-shaped bass horn that could go as low as 40 Hz.<ref name="ReferenceA"/> The Shearing-Lansing 500-A ended up being used in "screening rooms, dubbing theaters, and early sound reinforcement".<ref name="ReferenceA"/> In the late 1930s, Lansing created a smaller two-way speaker with a 15" woofer in a vented enclosure, which he called the Iconic system; it was used as a studio monitor and in high-end home hi-fi set-ups.<ref name="ReferenceA"/>\n\nDuring the 1940s [[swing era]], to get deeper bass, "pipelike opening[s]" were cut into speaker enclosures, creating [[bass reflex]] enclosures, as it was found that even a fairly inexpensive speaker enclosure, once modified in this way, could "transmit the driving power of a heavy...drumbeat\u2014and sometimes not much else\u2014to a crowded dancefloor."<ref name="Fink, Robert 2018. p. 105"/> Prior to the development of the first subwoofers, woofers were used to reproduce bass frequencies, usually with a crossover point set at 500 Hz and a 15" loudspeaker in an infinite baffle or in professional sound applications, a  "hybrid horn-loaded" bass reflex enclosure (such as the 15" [[Altec Lansing]] A-7 enclosure nicknamed the "Voice of the Theater", which was introduced in 1946).<ref name="Hill, Adam J. 2010">Hill, Adam J.; Hawksford, Malcolm O. J.; Rosenthal, Adam P.; Gand, Gary. "Subwoofer positioning, orientation and calibration for large-scale sound reinforcement". Audio Engineering Society Convention Paper 7981, presented at the 128th Convention, May 22\u201325, 2010, London, UK</ref> In the mid-1950s, the [[Academy of Motion Picture Arts and Sciences]] selected the "big, boxy" Altec A-7 as the industry standard for movie sound reproduction in theaters.<ref>{{cite web |url=https://www.soundandvision.com/content/living-legend-altec-lansings-%E2%80%98voice-theatre%E2%80%99 |title=Living Legend: Altec Lansing's 'Voice of the Theatre'|author=<!--Not stated--> |date=15 December 2016 |website=www.soundandvision.com |publisher=Sound and Vision |access-date=1 January 2019 }}</ref>\n\n In September 1964, Raymon Dones, of El Cerrito, California, received the first patent for a subwoofer specifically designed to augment omnidirectionally the low frequency range of modern stereo systems (US patent 3150739). Able to reproduce distortion-free low frequencies down to 15 cycles per second (15 Hz), a specific objective of Dones's invention was to provide portable sound enclosures capable of high fidelity reproduction of low frequency sound waves without giving an audible indication of the direction from which they emanated. Dones's loudspeaker was marketed in the US under the trade name "The Octavium"<ref>Octavium Product brochure Aladdin Electronics, Inc. Copyright 1965</ref> from the early 1960s to the mid-1970s. The Octavium was utilized by several recording artists of that era, most notably the [[Grateful Dead]], bassist [[Monk Montgomery]], bassist [[Nathan East]], and the [[Pointer Sisters]]. The Octavium speaker and Dones's subwoofer technology were also utilized, in a few select theaters, to reproduce low pitch frequencies for the 1974 blockbuster movie ''Earthquake''.  During the late 1960s, Dones's Octavium was favorably reviewed by audiophile publications including ''Hi-Fi News'' and ''Audio Magazine''.\n\nAnother early subwoofer enclosure made for home and studio use was the separate bass speaker for the Servo Statik 1 by New Technology Enterprises.<ref name="Archibald, Holt 2005">{{cite web|url=http://www.stereophile.com/floorloudspeakers/988infinity/index.html|title=Infinity IRS Beta loudspeaker|last=Archibald|first=Larry|author2=J. Gordon Holt |date=December 31, 2005|work=Stereophile|publisher=Source Interlink Media|access-date=January 18, 2011}}</ref> Designed as a prototype in 1966 by physicist Arnold Nudell and airline pilot Cary Christie in Nudell's garage, it used a second winding around a custom Cerwin Vega 18-inch (45 cm) driver to provide servo control information to the amplifier, and it was offered for sale at $1795, some 40% more expensive than any other complete loudspeaker listed at ''Stereo Review''.<ref name="Archibald, Holt 2005"/> In 1968, the two found outside investors and reorganized as [[Infinity Systems|Infinity]].<ref name="Archibald, Holt 2005"/> The subwoofer was reviewed positively in ''Stereophile'' magazine's winter 1968 issue as the SS-1 by Infinity. The SS-1 received very good reviews in 1970 from ''High Fidelity'' magazine.<ref name="Archibald, Holt 2005"/>\n[[File:Gene Czerwinski at AES Convention.jpg|thumb|left|180px|A display of [[Cerwin-Vega]] speaker enclosures at the 1975 Audio Engineering Society meeting.]]\nAnother of the early subwoofers was developed during the late 1960s by Ken Kreisel, the former president of the Miller & Kreisel Sound Corporation in Los Angeles. When Kreisel's business partner, Jonas Miller, who owned a high-end audio store in Los Angeles, told Kreisel that some purchasers of the store's high-end [[electrostatic speakers]] had complained about a lack of bass response in the electrostatics, Kreisel designed a powered woofer that would reproduce only those frequencies that were too low for the electrostatic speakers to convey.<ref>{{cite journal |author= Levitin, D. J. |title=The Audio Interview: M&K's Ken Kreisel |journal = [[Audio (magazine)|Audio]] |volume = 80 |date=February 1996 |pages = 28\u201334}}</ref> Infinity's full range electrostatic speaker system that was developed during the 1960s also used a woofer to cover the lower frequency range that its electrostatic arrays did not handle adequately.\n\n The first use of a subwoofer in a recording session was in 1973 for mixing the [[Steely Dan]] album ''[[Pretzel Logic]]'', when [[recording engineer]] [[Roger Nichols (recording engineer)|Roger Nichols]] arranged for Kreisel to bring a prototype of his subwoofer to [[Village Recorders]].<ref>{{cite journal |url=http://www.stereophile.com/interviews/136/ |journal=Stereophile |date=March 1997 |first=Wes |last=Phillips |title=Audio Odyssey: Ken Kreisel of M&K |access-date=April 24, 2010}}</ref> Further design modifications were made by Kreisel over the next ten years, and in the 1970s and 1980s by engineer [[John P. D'Arcy]]; [[record producer]] [[Daniel Levitin]] served as a [[consultant]] and "[[golden ear]]s" for the design of the [[Audio crossover|crossover network]] (used to partition the frequency spectrum so that the subwoofer would not attempt to reproduce frequencies too high for its effective range, and so that the main speakers would not need to handle frequencies too low for their effective range). In 1976, Kreisel created the first satellite speakers and subwoofer system, named "David and Goliath".<ref>{{cite web |url=http://www.kreiselsound.com/timeline.php |title=KEN KREISEL HISTORIC TIMELINE |author=<!--Not stated--> |website=www.kreiselsound.com |publisher=Kreisel |access-date=31 December 2018 }}</ref>\n\nSubwoofers received a great deal of publicity in 1974 with the movie [[Earthquake (1974 film)|''Earthquake'']], which was released in [[Sensurround]]. Initially installed in 17 U.S. theaters, the Cerwin Vega "Sensurround" system used large subwoofers that were driven by racks of 500 watt amplifiers, triggered by control tones printed on one of the audio tracks on the film. Four of the subwoofers were positioned in front of the audience under (or behind) the film screen and two more were placed together at the rear of the audience on a platform. Powerful noise energy and loud rumbling in the range of 17 Hz to 120 Hz were generated at the level of 110\u2013120 decibels of [[Sound pressure|sound pressure level]], abbreviated dB(SPL). The new low frequency entertainment method helped the film become a box office success. More Sensurround systems were assembled and installed. By 1976, there were almost 300 Sensurround systems leapfrogging through select theaters. Other films to use the effect include the WW II naval battle epic [[Midway (1976 film)|''Midway'']] in 1976 and [[Rollercoaster (1977 film)|''Rollercoaster'']] in 1977.<ref>{{cite web |url=http://www.in70mm.com/newsletter/2004/69/sensurround/about.htm |title=About Sensurround |work=The 70mm Newsletter |publisher=In70mm.com |date=January 26, 2010 |access-date=April 24, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100209071217/http://www.in70mm.com/newsletter/2004/69/sensurround/about.htm |archive-date=February 9, 2010 }}</ref>\n\nFor owners of 33 rpm LPs and 45 rpm singles, loud ''and'' deep bass was limited by the ability of the [[phonograph record]] stylus to track the groove.<ref name="aes.org"/> While some hi-fi aficionados had solved the problem by using other playback sources, such as [[Reel-to-reel audio tape recording|reel-to-reel tape players]] which were capable of delivering accurate, naturally deep bass from acoustic sources, or synthetic bass not found in nature, with the popular introduction of the compact cassette in the late 1960s it became possible to add more low frequency content to recordings.<ref name="Masterclass Professional Learning">{{cite web|url=http://www.record-producer.com/learn.cfm?a=44 |work=Record-Producer.com |publisher=Masterclass Professional Learning |date=April 12, 2007 |title=Mastering for vinyl vs. mastering for CD |archive-url=https://web.archive.org/web/20070821055003/http://www.record-producer.com/learn.cfm?a=44 |archive-date=August 21, 2007 |access-date=April 24, 2010}}</ref> By the mid-1970s, 12" vinyl singles, which allowed for "more bass volume", were used to record disco, reggae, dub and hip-hop tracks; dance club DJs played these records in clubs with subwoofers to achieve "physical and emotional" reactions from dancers.<ref name="Krukowski">{{cite web |url=https://pitchfork.com/features/oped/9667-drop-the-bass-a-case-against-subwoofers/ |title=Drop the Bass: A Case Against Subwoofers |last=Krukowski |first=Damon |date=17 June 2015 |website=pitchfork.com |publisher=Pitchfork |access-date=31 December 2018 }}</ref>\n\nIn the early 1970s, [[David Mancuso]] hired sound engineer Alex Rosner<ref name="Brewster, Bill p. 64">Brewster, Bill; Broughton, Frank. ''The Record Players: DJ Revolutionaries''. Black Cat. p. 64</ref> to design additional subwoofers for his disco dance events, along with "tweeter arrays" to "boost the treble and bass at opportune moments" at his private, underground parties at [[The Loft (New York City)|The Loft]].<ref name="Lawrence, Tim 2009. p. 204">Lawrence, Tim. "Beyond the Hustle: Seventies Social Dancing, Discotheque Culture and the Emergence of the Contemporary Club Dancer". In ''Ballroom, Boogie, Shimmy Sham, Shake: A Social and Popular Dance Reader'', ed. Julie Malnig. University of Illinois Press, 2009. p. 204</ref> The demand for sub-bass sound reinforcement in the 1970s was driven by the important role of "powerful bass drum" in disco, as compared with rock and pop; to provide this deeper range, a third crossover point from 40 Hz to 120 Hz (centering on 80 Hz) was added.<ref name="Hill, Adam J. 2010"/> The [[Paradise Garage]] [[discotheque]] in New York City, which operated from 1977 to 1987, had "custom designed 'sub-bass' speakers" developed by Alex Rosner's disciple, sound engineer Richard ("Dick") Long <ref name="Brewster, Bill p. 64"/> that were called "Levan Horns" (in honor of resident [[DJ]] [[Larry Levan]]).<ref name="Krukowski"/>\n\nBy the end of the 1970s, subwoofers were used in dance venue sound systems to enable the playing of "[b]ass-heavy dance music" that we "do not 'hear' with our ears but with our entire body".<ref name="Lawrence, Tim 2009. p. 204"/> At the club, Long used four Levan bass horns, one in each corner of the dancefloor, to create a "haptic and tactile quality" in the sub-bass that you could feel in your body.<ref name="Papenburg, Jens Gerrit 2016. p. 210">Papenburg, Jens Gerrit. "Enhanced Bass" in ''Sound as Popular Culture: A Research Companion'', edited by Jens Gerrit Papenburg, Holger Schulze. MIT Press, 2016. p. 210</ref> To overcome the lack of sub-bass frequencies on 1970s disco records (sub-bass frequencies below 60 Hz were removed during mastering), Long added a DBX 100 "Boom Box" [[Subharmonic synthesizer|subharmonic pitch generator]] into his system to synthesize 25 Hz to 50 Hz sub-bass from the 50 to 100 Hz bass on the records.<ref name="Papenburg, Jens Gerrit 2016. p. 210"/>\n\nBy the later 1970s, disco club sound engineers were using the same large Cerwin Vega Sensurround-style folded horn subwoofers that were used in ''Earthquake'' and similar movies in dance club system installations.<ref name="Hill, Adam J. 2010"/> In the early 1980s, Long designed a sound system for the [[Warehouse (nightclub)|Warehouse]] dance club, with "huge stacks of subwoofers" which created "deep and intense" bass frequencies that "pound[ed] through your system" and "entire body", enabling clubgoers to "viscerally experience" the DJs' [[house music]] mixes.<ref>Salkind, Micah. ''Do You Remember House?: Chicago's Queer of Color Undergrounds''. Oxford University Press, 2018 p. 60-61</ref>\n\n[[File:Sound System.jpg|thumb|right|200px|A crew sets up a sound system, including large bass bins, in Jamaica in 2009.]]\nIn Jamaica in the 1970s and 1980s, sound engineers for [[reggae]] [[sound system (Jamaican)|sound system]]s began creating "heavily customized" subwoofer enclosures by adding foam and tuning the cabinets to achieve "rich and articulate speaker output below 100 Hz".<ref name="Fink, Robert 2018. pp. 104\u2013105">Fink, Robert. "Below 100 Hz: Towards a Musicology of Bass Culture". In ''The Relentless Pursuit of Tone: Timbre in Popular Music'', eds. Fink, Robert; Latour, Melinda; Wallmark, Zachary. Oxford University Press, 2018. pp. 104\u2013105</ref> The sound engineers who developed the "bass-heavy signature sound" of sound reinforcement systems have been called "deserving as much credit for the sound of Jamaican music as their better-known music producer cousins".<ref>Henriques, Julian. ''Sonic Bodies: Reggae Sound Systems, Performance Techniques, and Ways of Knowing''. Bloomsbury.</ref> The sound engineers for [[Stone Love Movement]] (a sound system crew), for example, modified folded horn subwoofers they imported from the US to get more of a bass reflex sound that suited local tone preferences for [[dancehall]] audiences, as the unmodified folded horn was found to be "too aggressive" sounding and "not deep enough for Jamaican listeners".<ref name="Fink, Robert 2018. pp. 104\u2013105"/>\n\nIn sound system culture, there are both "low and high bass bins" in "towering piles" that are "delivered in large trucks" and set up by a crew of "box boys", and then positioned and adjusted by the sound engineer in a process known as "stringing up", all to create the "sound of reggae music you can literally feel as it comes off these big speakers".<ref>{{cite web |url=https://www.independent.co.uk/arts-entertainment/music/features/one-love-traditional-sound-systems-stringing-up-in-the-english-countryside-7932228.html |title=One love: Traditional sound systems 'stringing up' in the English countryside |last=Burrell |first=Ian |date=11 July 2012 |website=www.independent.co.uk |publisher=Independent |access-date=1 January 2019 }}</ref> Sound system crews hold '[[sound clash]]' competitions, where each sound system is set up and then the two crews try to outdo each other,<ref name="Stanley">Stanley Niaah, Sonia (2010) ''DanceHall: From Slave Ship to Ghetto'', University of Ottawa Press, {{ISBN|978-0776607368}}, p. 103</ref> both in terms of loudness and the "bass it produced".<ref>{{cite web |url=http://www.papermag.com/jamaica-sound-clash-culture-2598768982.html?rebelltitem=2#rebelltitem2|title=A Brief History of Jamaica's Iconic Sound Clash Culture|last=Rasool |first=Amira  |date=24 August 2018 |website=www.papermag.com |publisher=Paper Mag|access-date=9 January 2019 |quote=As much as sound systems and selectors were important, the speaker systems and the bass it produced, is what gave the battle its edge. Each crew fought to out blast the other with their speakers. In this battle, the louder the sound system, the louder the crowd. Not only did the sound of the speakers matter, but its overall display were judge too. Crews stacked speakers on top of one another and found innovative new ways to incorporate the physical presence of the speakers into the show. Large trucks would arrive with speakers systems attached to the back and turntables and the battling crew in tow.}}</ref>\n\n[[File:Bose Acoustimass 5 Series 1.jpg|left|thumb|The 1987 Bose Acoustimass 5 stereo bass driver contained one six-inch (152 mm) driver per channel and provided crossover filtering for its two cube speaker arrays.<ref>{{cite web |url=http://products.bose.com/pdf/customer_service/owners/am5_guide.pdf |publisher=Bose |title=Acoustimass 5 user manual |year=1987 |access-date=April 24, 2010}}</ref>]]\nIn the 1980s, the Bose Acoustimass AM-5 became a popular subwoofer and small high-range satellite speaker system for home listening.<ref name="Feinstein">{{cite web |url=https://www.audioholics.com/loudspeaker-design/most-influential-speakers |title=The Top Ten Most Influential Speakers of the Last 50 Years |last=Feinstein |first=Steve |date=31 December 2014 |website=www.audioholics.com |publisher=Audioholics |access-date=21 February 2019 }}</ref> Steve Feinstein stated that with the AM-5, the system's "appearance mattered as much as, if not more than, great sound" to consumers of this era, as it was considered to be a "cool" look.<ref name="Feinstein"/> The success of the AM-5 led to other makers launching subwoofer-satellite speaker systems, including Boston Acoustics Sub Sat 6 and 7, and the Cambridge SoundWorks Ensemble systems (by Kloss).<ref name="Feinstein"/> Claims that these sub-satellite systems showed manufacturers and designers that home theater systems with a hidden subwoofer could be "feasible and workable in a normal living room" for mainstream consumers. Despite criticism of the AM-5 from audio experts, regarding a lack of bass range below 60 Hz, an "acoustic hole" in the 120 to 200 Hz range and a lack of upper range above 13 kHz for the satellites, the AM-5 system represented 30% of the US speaker market in the early 1990s.<ref name="Feinstein"/>\n\nIn the 1980s, Origin Acoustics developed the first residential in-wall subwoofer named Composer. It used an aluminum 10" driver and a foam-lined enclosure designed to be mounted directly into wall studs during the construction of a new home.<ref>{{cite web |url=http://proaudioinc.com/news/news.php?stID=556 |title=Composer In-Wall Subwoofers |author=<!--Not stated--> |website=proaudioinc.com |publisher=Professional Audio |access-date=23 February 2019 }}</ref> The frequency response for the Composer is 30 Hz to 250 Hz.<ref>{{cite web |url=https://www.pacifichifi.com.au/products/origin-acoustics-composer-csub10nce-wall-subwoofer |title=Origin Acoustics Composer CSUB10NCE In-Wall Subwoofer |author=<!--Not stated--> |website=pacifichifi.com |publisher=Pacific HiFi |access-date=23 February 2019 }}</ref>\n\n While in the 1960s and 1970s deep bass speakers were once an exotic commodity owned by audiophiles, by the mid-1990s they were much more popular and widely used, with different sizes and capabilities of sound output.<ref>{{cite news|author=L. B. |date=Oct 1, 1995|title=How low can a speaker go? listen up|work=New York Times|id={{ProQuest|109399149}}}}</ref> An example of 1990s subwoofer use in sound reinforcement is the [[Ministry of Sound]] dance club which opened in 1991 in London. The dancefloor's sound system was based on Richard Long's design at Paradise Garage. The club spent about \u00a3500,000 on a sound system that used Martin Audio components in custom-built cabinets, including twelve 21" 9,500 watt active subwoofers, twelve 18" subwoofers and twelve Martin Audio W8C mid-high speakers.<ref>{{cite web |url=https://www.whathifi.com/features/inside-story-ministry-sound-sound-system |title=The inside story of the Ministry of Sound sound system |last=Cox |first=Joe |date=30 July 2015 |website=www.whathifi.com |publisher=What Hifi |access-date=2 January 2019 }}</ref>\n\nThe popularity of the CD made it possible to add more low frequency content to recordings and satisfy a larger number of consumers.<ref name="Masterclass Professional Learning"/> Home subwoofers grew in popularity, as they were easy to add to existing multimedia speaker setups and they were easy to position or hide.<ref>{{cite web |url=http://www.osd.rutgers.edu/gs/06papers/Subwoof.pdf |publisher=[[Rutgers University]] |first=Matthew |last=Rodriguez |author2=Erika Ross-O'Brien |author3=Kelli Martino |author4=Vanessa Lannaman |author5=Robert Nahas |author6=Joseph Civitello |author7=Christopher Roselle |author8=Rodrigo Colon |title=Experiences Designing and Building A Subwoofer Amplifier |year=2006 |access-date=April 24, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100803150020/http://www.osd.rutgers.edu/gs/06papers/Subwoof.pdf |archive-date=August 3, 2010 }}</ref> \nIn 2018, some [[electronic dance music]] (EDM) sound systems for venues that play hardcore bass have multiple subwoofer arrays to deal with mid-bass (80\u2013150 Hz), bass (40\u201380 Hz), and "[[Sub-bass|infra-bass]]" (20\u201340 Hz).<ref>Fink, Robert. "Below 100 Hz: Towards a Musicology of Bass Culture". In ''The Relentless Pursuit of Tone: Timbre in Popular Music'', eds. Fink, Robert; Latour, Melinda; Wallmark, Zachary.. Oxford University Press, 2018. p. 107</ref>\n\nIn 2015, [[Damon Krukowski]] wrote an article entitled "Drop the Bass: A Case Against Subwoofers" for ''[[Pitchfork (magazine)|Pitchfork]]'' magazine, based on his performing experience with [[Galaxie 500]]; he argues that "for certain styles of music", especially acoustic music genres, "these low-end behemoths are actually ruining our listening experience" by reducing the clarity of the low end.<ref>{{cite web |url=https://pitchfork.com/features/oped/9667-drop-the-bass-a-case-against-subwoofers/ |title=Drop the Bass: A Case Against Subwoofers |last=Krukowski |first=Damon |date=17 June 2015 |website=pitchfork.com |publisher=Pitchfork |access-date=31 December 2018 |quote=So turn off the subs and swap out the Beats if the music you\u2019re listening to was recorded pre-computer; or if it was recorded since but is focused on reproducing the sounds of physical instruments. Without that bass boost, you\u2019ll hear the low end with greater clarity. And you\u2019ll have a better chance at feeling the music's intended physical and emotional reactions.}}</ref> In 2015, John Hunter from REL Acoustics stated that audiophiles tend to "have a love/hate relationship with subwoofers" because most subs have "awful", "entry-level" sound quality and they are used in an "inappropriate way", without integrating the bass seamlessly.<ref>{{cite web |url=http://www.theabsolutesound.com/articles/john-hunter-rel-acoustics/ |title=John Hunter, REL Acoustics |last=Gader |first=Neil |date=12 May 2015 |website=www.theabsolutesound.com |publisher=The Absolute Sound |access-date=23 February 2019 }}</ref>"}},
{"article_title": "Loudspeaker", "pageid": "45871", "revid": "1062788839", "timestamp": "2021-12-30T14:58:17Z", "history_paths": [["Loudspeaker --- Introduction ---", "History"]], "categories": ["loudspeakers", "american inventions", "audiovisual introductions in 1924", "audio engineering", "music technology", "consumer electronics"], "heading_tree": {"Loudspeaker --- Introduction ---": {"Terminology": {}, "History": {"Moving-coil": {}, "First loudspeaker systems": {}}, "Driver design: dynamic loudspeakers": {"Diaphragm": {}, "Basket": {}, "Suspension": {}, "Cone materials": {"Full-range drivers": {}, "Subwoofer": {}, "Woofer": {}, "Mid-range driver": {}, "Tweeter": {}, "Coaxial drivers": {}}}, "System design": {"Crossover": {}, "Enclosures": {"Horn loudspeakers": {}, "Transmission line loudspeaker": {}}, "Wiring connections": {}, "Wireless speakers": {}}, "Specifications": {"Electrical characteristics of dynamic loudspeakers": {}, "Electromechanical measurements": {}, "Efficiency vs. sensitivity": {}}, "Listening environment": {"Placement": {}, "Directivity": {}}, "Other speaker designs": {"With a diaphragm": {"Moving-iron loudspeakers": {}, "Piezoelectric speakers": {}, "Magnetostatic loudspeakers": {}, "Magnetostrictive speakers": {}, "Electrostatic loudspeakers": {}, "Ribbon and planar magnetic loudspeakers": {}, "Bending wave loudspeakers": {}, "Flat panel loudspeakers": {}, "Heil air motion transducers": {}, "Transparent ionic conduction speaker": {}}, "Without a diaphragm": {"Plasma arc speakers": {}, "Thermoacoustic speakers": {}, "Rotary woofers": {}}, "New technologies": {"Digital speakers": {}}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Loudspeaker --- Introduction ---|History": "[[Johann Philipp Reis]] installed an electric loudspeaker in his ''[[telephone]]'' in 1861; it was capable of reproducing clear tones, but later revisions could also reproduce muffled [[speech]].<ref>{{cite web|url=http://www.integratednetworkcable.com/technology/the-forgotten-johann-philipp-reis|title=The Forgotten Johann Philipp Reis|website=Integrated Network Cables|access-date=2015-06-11}}</ref> [[Alexander Graham Bell]] patented his first electric loudspeaker (capable of reproducing intelligible speech) as part of his telephone in 1876, which was followed in 1877 by an improved version from [[Ernst Siemens]]. During this time, [[Thomas Edison]] was issued a British patent for a system using compressed air as an amplifying mechanism for his early cylinder phonographs, but he ultimately settled for the familiar metal horn driven by a membrane attached to the stylus. In 1898, Horace Short patented a design for a loudspeaker driven by compressed air; he then sold the rights to [[Charles Algernon Parsons|Charles Parsons]], who was issued several additional British patents before 1910. A few companies, including the [[Victor Talking Machine Company]] and [[Path\u00e9]], produced record players using compressed-air loudspeakers. Compressed-air designs are significantly limited by their poor sound quality and their inability to reproduce sound at low volume. Variants of the design were used for [[public address]] applications, and more recently, other variations have been used to test space-equipment resistance to the very loud sound and vibration levels that the launching of rockets produces.<ref>{{cite web |url=http://www.douglas-self.com/MUSEUM/COMMS/auxetophone/auxetoph.htm |title=The Auxetophone & Other Compressed-Air Gramophones |access-date=2019-01-20}}</ref>\n\n The first experimental moving-coil (also called ''dynamic'') loudspeaker was invented by [[Oliver Lodge]] in 1898.<ref>{{cite web|url=https://www.aes-media.org/historical/html/recording.technology.history/loudspeaker.html |title=Loudspeaker History |access-date=2019-01-20}}</ref> The first practical moving-coil loudspeakers were manufactured by Danish engineer [[Peter L. Jensen]] and Edwin Pridham in 1915, in [[Napa, California]].<ref name=korn>{{cite news |last1=Kornum |first=Rene |url=http://ing.dk/artikel/hoejttaleren-fylder-100-aar-og-foedselaren-er-dansk-179868 |title=The loudspeaker is 100 years old |work=[[Ingeni\u00f8ren]] |date=4 November 2015}}</ref>  Like previous loudspeakers these used horns to amplify the sound produced by a small diaphragm.  Jensen was denied patents. Being unsuccessful in selling their product to telephone companies, in 1915 they changed their target market to radios and [[public address system]]s, and named their product [[Magnavox]]. Jensen was, for years after the invention of the loudspeaker, a part owner of The Magnavox Company.<ref>{{cite web |url=https://www.aes-media.org/historical/html/recording.technology.history/jensen.html |title=Jensen History |access-date=2019-01-20}}</ref>\n\n[[Image:Edward Kellogg & Chester Rice with cone speaker 1925.jpg|thumb|upright=1.6|[[Edward W. Kellogg|Kellogg]] and [[Chester W. Rice|Rice]] in 1925 holding the large driver of the first moving-coil cone loudspeaker]]\n\n{{multiple image\n| align = right\n| direction = horizontal\n| header   =\n| image1   = Rice Kellogg loudspeaker 1.jpg\n| caption1 = Prototype moving-coil cone loudspeaker by Kellogg and Rice in 1925, with electromagnet pulled back, showing voice coil attached to cone\n| width1   = 150\n| image2   = Rice Kellogg loudspeaker 2.jpg\n| caption2 = The first commercial version of the speaker, sold with the RCA Radiola receiver, had only a 6-inch cone. In 1926 it sold for $250, equivalent to about $3000 today.\n| width2   = 250\n| footer   =\n}}\n\nThe moving-coil principle commonly used today in speakers was patented in 1925 by [[Edward W. Kellogg]] and [[Chester W. Rice]] issued as US Patent 1,707,570. Apr 2, 1929. The key difference between previous attempts and the patent by Rice and Kellogg is the adjustment of mechanical parameters to provide a reasonably flat [[frequency response]].<ref>{{cite journal|journal=Journal of the Audio Engineering Society|volume= 52|issue=4|year=2004|pages=412\u2013432 (p. 416)|url=http://www.aes.org/journal/online/JAES_V52/jaes.cfm?file=JAES_V52_4/JAES_V52_4_PG412.pdf|quote=The  key difference in the  Rice and Kellogg design  was the adjustment of mechanical parameters so that the fundamental resonance of the moving system took place at a  lower frequency than that at which the cone\u2019s radiation impedance had become uniform. Over this  range, the motion of the cone was mass controlled, and the cone looked into a rising radiation impedance. This in effect provided a significant frequency region of flat power response for the design.|author=[[John M. Eargle|J. Eargle]] and M. Gander|title=Historical Perspectives and Technology Overview of Loudspeakers for Sound Reinforcement}}</ref> \n\nThese first loudspeakers used [[electromagnet]]s, because large, powerful [[permanent magnet]]s were generally not available at a reasonable price. The coil of an electromagnet, called a field coil, was energized by a current through a second pair of connections to the driver. This winding usually served a dual role, acting also as a [[choke coil]], filtering the [[power supply]] of the [[audio power amplifier|amplifier]] that the loudspeaker was connected to.<ref>Henry B. O. Davis, ''Electrical and Electronic Technologies: A Chronology of Events and Inventors from 1900 to 1940'', Scarecrow Press, 1983, {{ISBN|0810815907}} page 75</ref> AC ripple in the current was attenuated by the action of passing through the choke coil. However, AC line frequencies tended to modulate the audio signal going to the voice coil and added to the audible hum. In 1930 [[Peter L. Jensen|Jensen]] introduced the first commercial fixed-magnet loudspeaker; however, the large, heavy iron magnets of the day were impractical and field-coil speakers remained predominant until the widespread availability of lightweight [[alnico]] magnets after World War II.\n\n In the 1930s, loudspeaker manufacturers began to combine two and three drivers or sets of drivers each optimized for a different frequency range in order to improve frequency response and increase [[sound pressure level]].<ref>{{Cite book|title=Audio Signal Processing and Coding |last=Spanias |first=Andreas |author2=Ted Painter |author3=Venkatraman Atti  |year=2007 |publisher=Wiley-Interscience |isbn=978-0-470-04196-3 |url=https://books.google.com/books?id=J7_nVWzx1Q4C }}</ref> In 1937, the first film industry-standard loudspeaker system, "The Shearer Horn System for Theatres",<ref>[http://www.lansingheritage.org/images/lmco/bulletins/2b.jpg Lansingheritage.com: (1937 brochure image) ''The Shearer Horn System for Theatres'']</ref> a two-way system, was introduced by [[Metro-Goldwyn-Mayer]]. It used four 15\u2033 low-frequency drivers, a crossover network set for 375 Hz, and a single multi-cellular horn with two compression drivers providing the high frequencies. [[John Kenneth Hilliard]], [[James Bullough Lansing]], and [[Douglas Shearer]] all played roles in creating the system. At the [[1939 New York World's Fair]], a very large two-way [[public address]] system was mounted on a tower at [[Flushing Meadows]]. The eight 27\u2033 low-frequency drivers were designed by [[Rudy Bozak]] in his role as chief engineer for Cinaudagraph. High-frequency drivers were likely made by [[Western Electric]].<ref>Bozak, R.T., ''Electronics'' magazine, June 1940.</ref>\n\n[[Altec Lansing]] introduced the ''604'', which became their most famous coaxial [[Altec Lansing Duplex|Duplex]] driver, in 1943. It incorporated a high-frequency horn that sent sound through a hole in the pole piece of a 15-inch woofer for near-point-source performance.<ref>[http://www.lansingheritage.org/images/altec/catalogs/1943/page05.jpg Lansing Heritage. ''Loudspeakers by Lansing: First Time in History. A Two-Way Loud Speaker in Compact Form.'' (1943 catalog image)]</ref> Altec's "Voice of the Theatre" loudspeaker system was first sold in 1945, offering better coherence and clarity at the high output levels necessary in movie theaters.<ref>[http://www.lansingheritage.org/images/altec/catalogs/1966-vott/page2.jpg Lansing Heritage. ''1966 Voice of the Theatre'' (catalog image)]</ref> The Academy of Motion Picture Arts and Sciences immediately began testing its sonic characteristics; they made it the [[cinema (place)|film house]] industry standard in 1955.<ref>Audioheritage.org. [http://www.audioheritage.org/html/people/hilliard.htm ''Biography of John Hilliard''], Retrieved on May 6, 2009.</ref>\n\nIn 1954, [[Edgar Villchur]] developed the [[acoustic suspension]] principle of loudspeaker design.  This allowed for better bass response than previously obtainable from drivers mounted in larger cabinets.<ref>{{Cite book|title=Revolutionary Loudspeaker and Enclosure |last=Villchur |first=Edgar|number=October |year=1954 |publisher=Audio Engineering |url=https://worldradiohistory.com/Archive-All-Audio/Archive-Audio/50s/Audio-1954-Oct.pdf |page=25 |access-date=October 9, 2021 }}</ref>  He and his partner [[Henry Kloss]] formed the [[Acoustic Research]] company to manufacture and market speaker systems using this principle.<ref>{{citation |url=http://www.aes.org/aeshc/jaes.obit/JAES_V59_12_PG1004.pdf |title=Edgar M. Villchur 1917-2011 |publisher=[[Audio Engineering Society]] |access-date=2021-10-12}}</ref>  Subsequently, continuous developments in enclosure design and materials led to significant audible improvements.{{Citation needed|date=June 2009}}\n\nThe most notable improvements to date in modern dynamic drivers, and the loudspeakers that employ them, are improvements in cone materials, the introduction of higher-temperature adhesives, improved permanent [[magnet]] materials, improved measurement techniques, computer-aided design, and finite element analysis.  At low frequencies, the application of electrical network theory to the acoustic performance allowed by various enclosure designs (initially by Thiele, and later by Small) has been very important at the design level.{{Citation needed|date=June 2009}}"}},
{"article_title": "35 mm movie film", "pageid": "46203", "revid": "1062337627", "timestamp": "2021-12-27T21:34:32Z", "history_paths": [["35 mm movie film --- Introduction ---", "History and development"]], "categories": ["film and video technology", "film formats", "motion picture film formats", "thomas edison"], "heading_tree": {"35 mm movie film --- Introduction ---": {"History and development": {"Early history": {"Becoming the standard": {}}, "Innovations in sound": {}, "Modern 3D systems": {}, "Decline": {}}, "Attributes": {"Color": {}, "Safety film": {}, "Other types": {}}, "Common formats": {"Academy format": {}, "Widescreen": {}, "Super 35": {}, "3-Perf": {}, "VistaVision": {}}, "Perforations": {"BH perforations": {}, "KS perforations": {}, "DH perforations": {}, "CS perforations": {}}, "Technical specifications": {}, "See also": {}, "Footnotes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"35 mm movie film --- Introduction ---|History and development": "{{See also|Film stock|Kinetoscope}}\n[[File:Eastman giving Edison the first roll of movie film 01.png|thumb|left|Eastman (L) giving Edison the first roll of movie film, which was 35 mm]]\nIn 1880, [[George Eastman]] began to manufacture [[gelatin]] dry photographic plates in [[Rochester, New York]]. Along with W. H. Walker, Eastman invented a holder for a roll of picture-carrying gelatin layer-coated paper. [[Hannibal Goodwin]] then invented a [[nitrocellulose]] [[film base]] in 1887, the first transparent, flexible film.<ref>{{cite magazine | url = https://www.wired.com/2011/05/0502celuloid-photographic-film/| date = 2 May 2011 | access-date = 29 August 2017 | first = Randy | last = Alfred | magazine = [[Wired (magazine)|Wired]] | title = May 2, 1887: Celluloid-Film Patent Ignites Long Legal Battle}}</ref><ref>{{cite web |url=https://www.pbs.org/wgbh/amex/eastman/timeline/index_2.html |title=The Wizard of Photography: The Story of George Eastman and How He Transformed Photography |work=Timeline PBS American Experience Online |access-date=July 5, 2006}}</ref> Eastman also produced these components, and his was the first major company to mass-produce such film when, in 1889, Eastman realized that the dry-gelatino-bromide [[emulsion]] could be coated onto this clear base, eliminating the paper.<ref>{{cite book |last=Mees |first=C. E. Kenneth |year=1961 |title=From Dry Plates to Ektachrome Film: A Story of Photographic Research |publisher=Ziff-Davis Publishing |pages=15\u201316}}</ref>\n\nWith the advent of flexible film, [[Thomas Edison]] quickly set out on his invention, the [[Kinetoscope]], which was first shown at the [[Brooklyn Institute of Arts and Sciences]] on May 9, 1893.<ref>{{cite book|last=Robinson|first=David|url=https://archive.org/details/frompeepshowtopa0000robi|title=From peep show to palace: the birth of American film|publisher=Columbia University Press|year=1996|isbn=978-0-231-10338-1|page=[https://archive.org/details/frompeepshowtopa0000robi/page/39 39]|url-access=registration}}</ref> The Kinetoscope was a film loop system intended for one-person viewing.<ref name="hone">{{cite book|url=https://books.google.com/books?id=Z_4VAAAACAAJ|title=Eastman Professional Motion Picture Films|date=June 1, 1983|publisher=Eastman Kodak Co|isbn=978-0-87985-477-5}}</ref> Edison, along with assistant [[William Kennedy Dickson]], followed that up with the [[Kinetoscope#Kinetophone|Kinetophone]], which combined the Kinetoscope with Edison's cylinder [[phonograph]]. Beginning in March 1892, Eastman and then, from April 1893 into 1896, New York's Blair Camera Co. supplied Edison with film stock.<ref name="JSMPE Dec 1933">{{cite journal|last=Dickson|first=W. K. L.|date=December 1933|title= A Brief History of the Kinetograph, the Kinetoscope and the Kineto-Phonograph |url=https://archive.org/stream/journalofsociety21socirich#page/434/mode/2up|journal= Journal of the Society of Motion Picture Engineers|volume=21|issue=6|pages=435\u2013455|doi=10.5594/J12965|access-date=March 13, 2012}}</ref><ref name="John Fullerton 3">{{cite book|last1=Fullerton|first1=John|url=https://books.google.com/books?id=9lMAfjLi1LEC|title=Moving images: from Edison to the Webcam|last2=S\u00f6derbergh-Widding|first2=Astrid|date=June 2000|publisher=John Libbey & Co Ltd|isbn=978-1-86462-054-2|page=3}}</ref> Dickson is credited as the inventor of 35 mm movie film in 1889,<ref name="Belton" /><sup>652</sup> when the Edison company was using Eastman film.<ref name="Belton" /><sup>653\u2013654</sup>{{refn|group=fn|name=dicksonsmpte|The actual dimension of 35 mm specified by the [[Society of Motion Picture and Television Engineers|SMPTE]] is {{convert|1.377|+/-|0.001|in}}. The size initially created by Dickson was only 0.075 mm narrower than the 35 mm standard that has existed since 1930. An account of this is given in an article by Dickson in the December 1933 SMPTE journal. This size was also exactly half the width of the {{convert|2+3/4|in|mm|adj=mid|wide}} "A-type" 120 and 620 rollfilm which was the standard Eastman size at the time. The standard size was increased at the May 1929 meeting of the SMPE and published in 1930.<ref>{{cite web |url=http://www.subclub.org/shop/halframe.htm |title=Half Frame Cameras |website=subclub.org |access-date=August 12, 2006}}</ref><ref>{{cite web |url=http://www.eastman.org/fm/mees/htmlsrc/mE12900002_ful.html |title=Enhancing the Illusion: The Process and Origins of Photography |website=George Eastman House |access-date=August 12, 2006 |archive-url=https://web.archive.org/web/20080117183418/http://www.eastman.org/fm/mees/htmlsrc/mE12900002_ful.html |archive-date=17 January 2008}}</ref>}} The company still received film from Blair after this; at first Blair would supply only {{convert|40|mm|frac=16|abbr=on|adj=on}} film stock that would be trimmed and perforated at the Edison lab to create {{convert|1+3/8|in|adj=on}} gauge filmstrips, then at some point in 1894 or 1895, Blair began sending stock to Edison that was cut exactly to specification.<ref name="JSMPE Dec 1933" /><ref name="John Fullerton 3" /> Edison's [[aperture]] defined a single frame of film at four [[Film perforations|perforations]] high.<ref name="katz">{{cite book|last=Katz|first=Ephraim|url=https://archive.org/details/filmencyclopedia0katz|title=The Film Encyclopedia|publisher=HarperCollins|year=1994|isbn=978-0-06-273089-3|url-access=registration}}</ref> \n\nFor a time, it had been generally assumed that Dickson was following cinematography formats established by Eastman in producing the film, but Eastman had produced film in sheets that were then cut to order.<ref name="Belton" /><sup>652\u2013653</sup> Dickson used the film supplied for [[Eastman Kodak]] cameras in 1889, a transparent [[70 mm film|70 mm]] celluloid film, in his development of a more suitable [[film stock]], and "simply slit this film in half";<ref name="Belton" /><sup>653\u2013654</sup> it was initially developed for the Kinetoscope, a one-person viewer, not to be projected.<ref name="Belton" /><sup>658</sup> The image was still of high quality, even when magnified, and was more economical than 70 mm film (and more economical than any other gauge, as cutting the 70 mm to size would have created waste).<ref name="Belton" /><sup>654</sup> 35 mm was immediately accepted as standard by the [[Auguste and Louis Lumi\u00e8re|Lumi\u00e8re brothers]], and became the main film used in the UK because it was the stock sold to these filmmakers by the Blair company.<ref name=Belton>{{cite journal|url=https://ieeexplore.ieee.org/document/7228070|title=The Origins of 35mm Film as a Standard|last=Belton|first=John|journal= Journal of the Society of Motion Picture and Television Engineers|volume=99|issue=8|date=August 1990|pages=652\u2013661|doi=10.5594/J02613|issn=0036-1682}}</ref><sup>653</sup>\n\nEdison claimed exclusive [[patent]] rights to the design of 35 mm motion picture film{{refn|group=fn|{{US patent|0589168}}}}, with four sprocket holes (perforations) per frame, forcing his only major filmmaking competitor, [[American Mutoscope & Biograph]], to use a 68 mm film that used friction feed, not sprocket holes, to move the film through the camera. A court judgment in March 1902 invalidated Edison's claim, allowing any producer or distributor to use the Edison 35 mm film design without license. Filmmakers were already doing so in Britain and Europe, where Edison did not file patents.<ref>{{cite book |last=Musser |first=Charles |title=The Emergence of Cinema: The American Screen to 1907 |url=https://books.google.com/books?id=IEUMWToGOtUC |year=1994 |publisher=University of California Press |location=Berkeley, California |isbn=978-0-520-08533-6 |pages=303\u2013313}}</ref> At the time, film stock was usually supplied unperforated and punched by the filmmaker to their standards with perforation equipment. A variation developed by the Lumi\u00e8re brothers used a single circular perforation on each side of the frame towards the middle of the horizontal axis.<ref name="lumiere">Lobban, Grant. "Film Gauges and Soundtracks", BKSTS wall chart (sample frame provided). [Year unknown]</ref>\n\n [[File:Dickson's 35 mm movie film standard and 35 mm patent design.png|thumb|left|Dickson's 35 mm movie film standard (center)]]\nWhen films began to be projected, several projection devices were unsuccessful and fell into obscurity because of technical failure, lack of business acumen, or both. The [[Vitascope]], the first projection device to use 35 mm, was technologically superior and compatible with the many motion pictures produced on 35 mm film. Edison bought the device in 1895\u201396; the Lumiere's 35 mm projection [[Cinematograph]] also premiered in 1895, and they established 35 mm as the standard for exhibition.<ref name="Belton" /><sup>658</sup>\n\nStandardization in recording came from monopolization of the business by Eastman and Edison, and because of Edison's typical business model involving the patent system: Eastman and Edison managed their film patents well<ref name="Belton" /><sup>656</sup> \u2013 Edison filed the 35 mm patent in 1896, the year after Dickson left his employ<ref name="Belton" /><sup>657</sup> \u2013 and so controlled the use and development of film.<ref name="Belton" /><sup>656</sup> Dickson left the Edison company in 1895, going on to help competitors produce cameras and other film gauges that would not infringe on [[List of Edison patents|Edison's patents]]. However, by 1900, filmmakers found it too expensive to develop and use other gauges, and went back to using the cheap and widely-available 35 mm.<ref name="Belton" /><sup>657</sup>\n\nDickson said in 1933:\n{{quote|At the end of the year 1889, I increased the width of the picture from {{frac||1|2}} inch to {{frac||3|4}} inch, then, to 1 inch by {{frac||3|4}} inch high. The actual width of the film was {{frac|1|3|8}} inches to allow for the perforations now punched on both edges, 4 holes to the phase or picture, which perforations were a shade smaller than those now in use. This standardized film size of 1889 has remained, with only minor variations, unaltered to date".<ref name="Belton" /><sup>652</sup>}}\n\nUntil 1953, the 35 mm film was seen as "basic technology" in the film industry, rather than optional, despite other gauges being available.<ref name="Belton" /><sup>652</sup>\n\n[[File:35mm film format with optical soundtrack.svg|thumb|right|upright=1.5|35 mm film diagram]]\nIn 1908, Edison formed "a cartel of production companies", a [[trust (19th century)|trust]] called the [[Motion Picture Patents Company]] (MPPC), pooling patents for collective use in the industry and positioning Edison's own technology as the standard to be licensed out.<ref name="Belton" /><sup>656</sup> 35 mm became the "official" standard of the newly formed MPPC, which agreed in 1909 to what would become the standard: 35 mm gauge, with Edison perforations and a 1.3{{overline|3}}:1 (4:3) [[aspect ratio (image)|aspect ratio]] (also developed by Dickson).<ref name="Belton" /><sup>652</sup><ref group="fn">The gauge and perforations are almost identical to modern film stock; the full silent ratio is also used as the [[film gate]] in movie cameras, although portions of the image are later cropped out in post-production and projection.</ref> Scholar Paul C. Spehr describes the importance of these developments:\n{{quote|The early acceptance of 35 mm as a standard had momentous impact on the development and spread of cinema. The standard gauge made it possible for films to be shown in every country of the world\u2026 It provided a uniform, reliable and predictable format for production, distribution and exhibition of movies, facilitating the rapid spread and acceptance of the movies as a world-wide device for entertainment and communication.<ref name="John Fullerton 3"/>}}\n\nWhen the MPPC adopted the 35 mm format, [[Bell & Howell]] produced cameras, projectors, and perforators for the medium of an "exceptionally high quality", further cementing it as the standard.<ref name="Belton" /><sup>659</sup> Edison and Eastman's form of business manipulation was ruled unlawful in 1914, but by this time the technology had become the established standard.<ref name="Belton" /><sup>657</sup> In 1917, the new [[Society of Motion Picture and Television Engineers]] (SMPTE) "acknowledged the de facto status of 35mm as the industry\u2019s dominant film gauge, adopting it as an engineering standard".<ref name="Belton" /><sup>659</sup>\n\n [[File:35mm film audio macro.jpg|thumb|right|upright=0.9|A photo of a 35 mm film print featuring all four audio formats (or "quad track") \u2014 from left to right: [[Sony Dynamic Digital Sound|SDDS]], a soundtrack as an image of a digital signal (blue area to the left of the sprocket holes); [[Dolby Digital]] sound (grey area between the sprocket holes labelled with the Dolby "Double-D" logo in the middle); [[Dolby Stereo|analog optical sound]], optically recorded as waveforms containing the audio signals for the left and right audio channels (the two white lines to the right of the sprocket holes); and the [[Digital Theater System|DTS]] [[time code]] (the dashed line to the far right).]]\nWhen film editing was done by physically cutting the film, editing the picture could only been done on the frame line. However, the sound was stored for the whole frame between each of the four sprocket holes, and so the sound editors could "cut on any arbitrary set of holes, and thus get {{frac||1|4}}-frame edit resolution. With this technique, an audio edit could be accurate to within 10.41 [[Millisecond|ms]]."<ref name=Rose>{{cite book |hdl=1853/50482 |chapter=Reality (sound)bites: Audio tricks from the film and TV studio |title=International Conference on Auditory Display |last=Rose |first=Jay |date=July 2003}}</ref><sup>1\u20132</sup> A limitation of [[Analog recording|analog optical recording]] was the projection frequency would cut off, in a well-maintained theater, at around 12[[Hertz|kHz]].<ref name=Rose/><sup>4</sup> Studios would often record audio on the transparent film strips, but with [[magnetic tape]] on one edge; recording audio on full 35 mm magnetic tape was more expensive.<ref name=Rose/><sup>5</sup>\n\nThree different digital soundtrack systems for 35 mm cinema release prints were introduced during the 1990s. They are: [[Dolby Digital]], which is stored between the perforations on the sound side; [[Sony Dynamic Digital Sound|SDDS]], stored in two [[redundancy (engineering)|redundant]] strips along the outside edges (beyond the perforations); and [[Digital Theatre System|DTS]], in which sound data is stored on separate [[compact disc]]s synchronized by a [[timecode]] track on the film just to the right of the analog soundtrack and left of the frame.<ref>{{cite web |url=http://www.dts.com/Corporate/About_Us/Milestones.aspx |website=DTS |title=Corporate Milestones |url-status=dead |archive-url=https://web.archive.org/web/20100609183206/http://www.dts.com/Corporate/About_Us/Milestones.aspx |archive-date=2010-06-09 }}</ref> Because these soundtrack systems appear on different parts of the film, one movie can contain all of them, allowing broad distribution without regard for the sound system installed at individual theatres.\n\nThe analogue optical track technology has also changed: in the early years of the 21st century, distributors changed to using [[cyan]] dye optical soundtracks instead of applicated tracks, which use environmentally unfriendly chemicals to retain a silver (black-and-white) soundtrack. Because traditional [[Incandescent light bulb|incandescent]] [[Optical sound#Film and radio|exciter lamps]] produce copious amounts of [[infrared light]], and cyan tracks do not absorb infrared light, this change has required theaters to replace the incandescent exciter lamp with a complementary colored red [[LED]] or [[Laser light|laser]]. These LED or laser exciters are backwards-compatible with older tracks.<ref name="cyan">{{cite web |last=Hull |first=Joe |url=http://www.dyetracks.org/FJI_Sept04.pdf |title=Committed to Cyan |website=dyetracks.org |access-date=August 11, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060921125129/http://www.dyetracks.org/FJI_Sept04.pdf |archive-date=September 21, 2006 }}</ref> The film ''[[Anything Else]]'' (2003) was the first to be released with only cyan tracks.<ref name="cyan" />\n\nTo facilitate this changeover, intermediate prints known as "high magenta" prints were distributed. These prints used a silver plus dye soundtrack that were printed into the magenta dye layer. The advantage gained was an optical soundtrack, with low levels of sibilant (cross-modulation) distortion, on both types of sound heads.<ref name="kodak-cyan">{{cite web |website=Kodak |url=http://motion.kodak.com/US/en/motion/Support/Technical_Information/Lab_Tools_And_Techniques/Cyan_Dye_Tracks/guide.htm |title=Cyan Dye Tracks Laboratory Guide |url-status=dead |archive-url=https://web.archive.org/web/20091126055003/http://motion.kodak.com/US/en/motion/Support/Technical_Information/Lab_Tools_And_Techniques/Cyan_Dye_Tracks/guide.htm |archive-date=2009-11-26 }}</ref>\n\n [[File:Over-Under 3D image.JPG|thumb|left|An "over-under" 3D frame. Both left and right eye images are contained within the normal height of a single 2D frame.]]\nThe success of digitally projected 3D movies in the first two decades of the 21st century led to a demand from some theater owners to be able to show these movies in 3D without incurring the high capital cost of installing digital projection equipment. To satisfy that demand, a number of systems had been proposed for 3D systems based on 35 mm film by [[Technicolor]],<ref>{{cite web |url=http://www.technicolor.com/en/hi/cinema |title=Entertainment Services |work=Technicolor |access-date=29 August 2016 |archive-url=https://web.archive.org/web/20111024021545/http://www.technicolor.com/en/hi/cinema |archive-date=2011-10-24 |url-status=dead }}</ref> [[Panavision]]<ref>{{cite journal |title=Seeing is Believing |journal=Cinema Technology |volume=24 |number=1 |date=March 2011}}</ref> and others. These systems are improved versions of the [[3-D film#Revival (1960\u20131984) in single strip format|"over-under" stereo]] 3D prints first introduced in the 1960s.\n\nTo be attractive to exhibitors, these schemes offered [[3D film]]s that can be projected by a standard 35 mm cinema projector with minimal modification, and so they are based on the use of "over-under" film prints. In these prints a left-right pair of 2.39:1 non-anamorphic images are substituted for the one 2.39:1 anamorphic image of a 2D "scope" print. The frame dimensions are based on those of the [[Techniscope]] 2-perf camera format used in the 1960s and 1970s. However, when used for 3D the left and right frames are pulled down together, thus the standard 4-perf pulldown is retained, minimising the need for modifications to the projector or to long-play systems. The linear speed of film through the projector and sound playback both remain exactly the same as in normal 2D operation.\n\nThe Technicolor system uses the polarisation of light to separate the left and right eye images and for this they rent to exhibitors a combination splitter-polarizer-lens assembly which can be fitted to a lens turret in the same manner as an anamorphic lens. In contrast, the Panavision system uses a spectral comb filter system, but their combination splitter-filter-lens is physically similar to the Technicolor assembly and can be used in the same way. No other modifications are required to the projector for either system, though for the Technicolor system a silver screen is necessary, as it would be with polarised-light digital 3D. Thus a programme can readily include both 2D and 3D segments with only the lens needing to be changed between them.\n\nIn June 2012, Panavision 3D systems for both 35 mm film and digital projection were withdrawn from the market by DVPO theatrical (who marketed these system on behalf of Panavision) citing "challenging global economic and 3D market conditions".<ref>{{cite web |url=http://www.dpvotheatrical.com/Home_Page.html |title=Home |website=DVPO Theatrical |url-status=dead |archive-url=https://web.archive.org/web/20120407125922/http://www.dpvotheatrical.com/Home_Page.html |archive-date=2012-04-07 }}</ref>\n\n In the transition period centered around 2010\u20132015, the rapid conversion of the cinema exhibition industry to [[digital cinema|digital projection]] has seen 35 mm film projectors removed from most of the projection rooms as they were replaced by digital projectors. By the mid-2010s, most of the theaters across the world have been converted to digital projection, while others are still running 35 mm projectors.<ref>{{cite journal |url=https://variety.com/2013/film/news/digital-cinema-conversion-nears-end-game-1200500975/ |title=Digital Cinema Conversion Nears End Game |first=Leo |last=Barraclough |date=23 June 2013 |journal=[[Variety (magazine)|Variety]] |access-date=29 August 2016}}</ref> In spite of the uptake in digital projectors installed in global cinemas, 35 mm film remains in a [[Niche market|niche]] market of enthusiasts and format lovers."}},
{"article_title": "Refrigeration", "pageid": "46238", "revid": "1062267752", "timestamp": "2021-12-27T11:36:18Z", "history_paths": [["Refrigeration --- Introduction ---", "History"]], "categories": ["chemical processes", "cooling technology", "food preservation", "heating, ventilation, and air conditioning", "thermodynamics"], "heading_tree": {"Refrigeration --- Introduction ---": {"History": {"Earliest forms of cooling": {}, "Ice harvesting": {}, "Refrigeration research": {}, "Commercial use": {}, "Home and consumer use": {}}, "Impact on settlement patterns": {"Refrigerated rail cars": {}, "Expansion west and into rural areas": {}, "Rise of the galactic city": {}}, "Impact on agriculture and food production": {"Demographics": {}, "Meat packing and trade": {}, "Electricity in rural areas": {}, "Farm use": {}}, "Effects on lifestyle and diet": {"Impact on nutrition": {}}, "Current applications of refrigeration": {}, "Methods of refrigeration": {"Non-cyclic refrigeration": {}, "Cyclic refrigeration": {"Vapor-compression cycle": {}, "Sorption cycle": {"Absorption cycle": {}, "Adsorption cycle": {}}, "Gas cycle": {}}, "Thermoelectric refrigeration": {}, "Magnetic refrigeration": {}, "Other methods": {}, "Elastocaloric refrigeration": {}, "Fridge Gate": {}, "Passive systems": {}}, "Capacity ratings": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Refrigeration --- Introduction ---|History": "{{Main|Timeline of low-temperature technology}}\n\n The seasonal harvesting of snow and ice is an ancient practice estimated to have begun earlier than 1000 BC.<ref name=":0">{{cite book|last=Neuburger|first=Albert|title=The technical arts and sciences of the ancients|year=2003|publisher=Kegan Paul|location=London|isbn=978-0-7103-0755-2|page=122}}</ref> A Chinese collection of lyrics from this time period known as the ''[[Shijing]]'', describes religious ceremonies for filling and emptying ice cellars. However, little is known about the construction of these ice cellars or the purpose of the ice. The next ancient society to record the harvesting of ice may have been the Jews in the book of Proverbs, which reads, \u201cAs the cold of snow in the time of harvest, so is a faithful messenger to them who sent him.\u201d Historians have interpreted this to mean that the Jews used ice to cool beverages rather than to preserve food. Other ancient cultures such as the Greeks and the Romans dug large snow pits insulated with grass, chaff, or branches of trees as cold storage. Like the Jews, the Greeks and Romans did not use ice and snow to preserve food, but primarily as a means to cool beverages. The Egyptians also developed methods to cool beverages, but in lieu of using ice to cool water, the Egyptians cooled water by putting boiling water in shallow earthen jars and placing them on the roofs of their houses at night. Wind would moisten the outside of the jars and the resulting evaporation would cool the water. The ancient people of India used this same concept to produce ice. The Persians stored ice in a pit called a [[Yakhchal]] and may have been the first group of people to use cold storage to preserve food. In the Australian outback before a reliable electricity supply was available where the weather could be hot and dry, many farmers used a [[Coolgardie safe]]. This consisted of a room with [[hessian fabric|hessian]] (burlap) curtains hanging from the ceiling soaked in water. The water would evaporate and thereby cool the hessian curtains and thereby the air circulating in the room. This would allow many perishables such as fruit, butter, and cured meats to be kept that would normally spoil in the heat.<ref>{{cite book|last=Neuburger|first=Albert|title=The technical arts and sciences of the ancients|year=2003|publisher=Kegan Paul|location=London|isbn=978-0-7103-0755-2|pages=122\u2013124}}</ref><ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=5\u20136}}</ref>\n\n {{See also|Ice cutting|Ice trade}}\n[[File:Ice Harvesting, Massachusetts, early 1850s.jpg|thumb|Ice harvesting in [[Massachusetts]], 1852, showing the [[railroad]] line in the background, used to transport the ice.]]\nBefore 1830, few Americans used ice to refrigerate foods due to a lack of ice-storehouses and iceboxes. As these two things became more widely available, individuals used axes and saws to [[ice cutting|harvest ice]] for their storehouses. This method proved to be difficult, dangerous, and certainly did not resemble anything that could be duplicated on a commercial scale.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=8\u201311}}</ref>\n\nDespite the difficulties of harvesting ice, Frederic Tudor thought that he could capitalize on this new commodity by harvesting ice in New England and shipping it to the Caribbean islands as well as the southern states. In the beginning, Tudor lost thousands of dollars, but eventually turned a profit as he constructed icehouses in Charleston, Virginia and in the Cuban port town of Havana. These icehouses as well as better insulated ships helped reduce ice wastage from 66% to 8%. This efficiency gain influenced Tudor to expand his ice market to other towns with icehouses such as New Orleans and Savannah. This ice market further expanded as harvesting ice became faster and cheaper after one of Tudor's suppliers, Nathaniel Wyeth, invented a horse-drawn ice cutter in 1825. This invention as well as Tudor's success inspired others to get involved in the [[ice trade]] and the ice industry grew.\n\nIce became a mass-market commodity by the early 1830s with the price of ice dropping from six cents per pound to a half of a cent per pound. In New York City, ice consumption increased from 12,000 tons in 1843 to 100,000 tons in 1856. Boston's consumption leapt from 6,000 tons to 85,000 tons during that same period. Ice harvesting created a \u201ccooling culture\u201d as majority of people used ice and iceboxes to store their dairy products, fish, meat, and even fruits and vegetables. These early cold storage practices paved the way for many Americans to accept the refrigeration technology that would soon take over the country.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=11\u201313}}</ref><ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=20\u201323|edition=1st Harvard University Press pbk.}}</ref>\n\n [[File:William Cullen.jpg|thumb|upright|[[William Cullen]], the first to conduct experiments into artificial refrigeration.]]\nThe history of artificial refrigeration began when Scottish professor [[William Cullen]] designed a small refrigerating machine in 1755. Cullen used a pump to create a partial [[vacuum]] over a container of [[diethyl ether]], which then [[boiling point|boiled]], absorbing [[heat of vaporization|heat]] from the surrounding air.<ref>{{cite book|last=Arora|first=Ramesh Chandra|title=Refrigeration and Air Conditioning|publisher=PHI Learning|location=New Delhi|isbn=978-81-203-3915-6|page=3|chapter=Mechanical vapour compression refrigeration|year=2012}}</ref> The experiment even created a small amount of ice, but had no practical application at that time.\n\nIn 1758, [[Benjamin Franklin]] and [[John Hadley (chemist)|John Hadley]], professor of chemistry, collaborated on a project investigating the principle of evaporation as a means to rapidly cool an object at [[Cambridge University]], [[England]]. They confirmed that the evaporation of highly volatile liquids, such as alcohol and ether, could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to quicken the evaporation; they lowered the temperature of the thermometer bulb down to {{convert|7|\u00b0F|\u00b0C|abbr=on|order=flip}}, while the ambient temperature was {{convert|65|\u00b0F|\u00b0C|abbr=on|order=flip}}. They noted that soon after they passed the freezing point of water {{convert|0|\u00b0C|\u00b0F|abbr=on}}, a thin film of ice formed on the surface of the thermometer's bulb and that the ice mass was about a {{convert|1/4|in|mm|order=flip}} thick when they stopped the experiment upon reaching {{convert|7|\u00b0F|\u00b0C|abbr=on|order=flip}}. Franklin wrote, "From this experiment, one may see the possibility of freezing a man to death on a warm summer's day".<ref>[http://www.historycarper.com/resources/twobf3/letter1.htm Cooling by Evaporation (Letter to John Lining)] {{webarchive|url=https://web.archive.org/web/20110128075748/http://www.historycarper.com/resources/twobf3/letter1.htm |date=2011-01-28}}. Benjamin Franklin, London, June 17, 1758</ref> In 1805, American inventor [[Oliver Evans]] described a closed [[vapor-compression refrigeration]] cycle for the production of ice by ether under vacuum.\n\nIn 1820 the English scientist [[Michael Faraday]] liquefied [[ammonia]] and other gases by using high pressures and low temperatures, and in 1834, an American expatriate to Great Britain, [[Jacob Perkins]], built the first working vapor-compression refrigeration system in the world. It was a closed-cycle that could operate continuously, as he described in his patent:\n:I am enabled to use volatile fluids for the purpose of producing the cooling or freezing of fluids, and yet at the same time constantly condensing such volatile fluids, and bringing them again into operation without waste.\n\nHis prototype system worked although it did not succeed commercially.<ref name=burstall>{{cite book |last= Burstall |first= Aubrey F. |year= 1965 |title= A History of Mechanical Engineering |publisher= The MIT Press |isbn= 978-0-262-52001-0}}</ref>\n\nIn 1842, a similar attempt was made by American physician, [[John Gorrie]],<ref>{{Cite web|url=https://pdfpiw.uspto.gov/.piw?Docid=00008080&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%2526Sect2%3DHITOFF%2526d%3DPALL%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r%3D1%2526f%3DG%2526l%3D50%2526s1%3D0008080.PN.%2526OS%3DPN%2F0008080%2526RS%3DPN%2F0008080&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|title=Patent Images}}</ref> who built a working prototype, but it was a commercial failure. Like many of the medical experts during this time, Gorrie thought too much exposure to tropical heat led to mental and physical degeneration, as well as the spread of diseases such as malaria.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=23|edition=1st Harvard University Press pbk.}}</ref> He conceived the idea of using his refrigeration system to cool the air for comfort in homes and hospitals to prevent disease. American engineer [[Alexander Twining]] took out a British patent in 1850 for a vapour compression system that used ether.\n\nThe first practical vapour-compression refrigeration system was built by [[James Harrison (engineer)|James Harrison]], a British journalist who had emigrated to [[Australia]]. His 1856 patent was for a vapour-compression system using ether, alcohol, or ammonia. He built a mechanical ice-making machine in 1851 on the banks of the Barwon River at Rocky Point in [[Geelong]], [[Victoria (Australia)|Victoria]], and his first commercial ice-making machine followed in 1854. Harrison also introduced commercial vapour-compression refrigeration to breweries and meat-packing houses, and by 1861, a dozen of his systems were in operation. He later entered the debate of how to compete against the American advantage of unrefrigerated [[beef]] sales to the [[United Kingdom]]. In 1873 he prepared the sailing ship ''Norfolk'' for an experimental beef shipment to the United Kingdom, which used a cold room system instead of a refrigeration system. The venture was a failure as the ice was consumed faster than expected.\n\n[[File:AppareilCarr\u00e9.jpg|thumb|left|[[Ferdinand Carr\u00e9]]'s ice-making device]]\nThe first [[absorption refrigeration|gas absorption]] refrigeration system using gaseous ammonia dissolved in water (referred to as "aqua ammonia") was developed by [[Ferdinand Carr\u00e9]] of France in 1859 and patented in 1860. [[Carl von Linde]], an engineer specializing in [[steam locomotive]]s and professor of engineering at the [[Technische Universit\u00e4t M\u00fcnchen|Technological University of Munich]] in Germany, began researching refrigeration in the 1860s and 1870s in response to demand from brewers for a technology that would allow year-round, large-scale production of [[lager]]; he patented an improved method of liquefying gases in 1876.<ref>{{cite episode |title= Eat, Drink, and Be Merry |series= Connections |series-link=Connections (British documentary)|credits= [[James Burke (science historian)|James Burke]] |network=BBC |date=1979 |number= 8|minutes=41\u201349 |language=en}}</ref> His new process made possible using gases such as [[ammonia]], [[sulfur dioxide]] (SO<sub>2</sub>) and [[methyl chloride]] (CH<sub>3</sub>Cl) as refrigerants and they were widely used for that purpose until the late 1920s.\n\n[[Thaddeus Lowe]], an American balloonist, held several patents on ice-making machines. His "Compression Ice Machine" would revolutionize the cold-storage industry. In 1869 other investors and he purchased an old steamship onto which they loaded one of Lowe's refrigeration units and began shipping fresh fruit from New York to the Gulf Coast area, and fresh meat from Galveston, Texas back to New York, but because of Lowe's lack of knowledge about shipping, the business was a costly failure.\n\n {{See also|Refrigerator}}\n[[File:Early refrigerator car design circa 1870.jpg|thumb|An 1870 refrigerator car design. Hatches in the roof provided access to the tanks for the storage of harvested ice at each end.|right]]\n[[File:AndrewMuhlPatent02.png|thumb|Icemaker Patent by Andrew Muhl, dated December 12, 1871.]]\nIn 1842 [[John Gorrie]] created a system capable of refrigerating water to produce ice. Although it was a commercial failure, it inspired scientists and inventors around the world. France's Ferdinand Carre was one of the inspired and he created an ice producing system that was simpler and smaller than that of Gorrie. During the Civil War, cities such as New Orleans could no longer get ice from New England via the coastal ice trade. Carre's refrigeration system became the solution to New Orleans ice problems and by 1865 the city had three of Carre's machines.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=25}}</ref> In 1867, in San Antonio, Texas, a French immigrant named Andrew Muhl built an ice-making machine to help service the expanding beef industry before moving it to Waco in 1871. In 1873, the patent for this machine was contracted by the Columbus Iron Works, a company acquired by the W.C. Bradley Co., which went on to produce the first commercial ice-makers in the US.\n\nBy the 1870s breweries had become the largest users of harvested ice. Though the ice-harvesting industry had grown immensely by the turn of the 20th century, pollution and sewage had begun to creep into natural ice, making it a problem in the metropolitan suburbs. Eventually, breweries began to complain of tainted ice. Public concern for the purity of water, from which ice was formed, began to increase in the early 1900s with the rise of germ theory. Numerous media outlets published articles connecting diseases such as typhoid fever with natural ice consumption. This caused ice harvesting to become illegal in certain areas of the country. All of these scenarios increased the demands for modern refrigeration and manufactured ice. Ice producing machines like that of Carre's and Muhl's were looked to as means of producing ice to meet the needs of grocers, farmers, and food shippers.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=25|edition=1st Harvard University Press pbk.}}</ref><ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=110\u2013111}}</ref>\n\nRefrigerated railroad cars were introduced in the US in the 1840s for short-run transport of dairy products, but these used harvested ice to maintain a cool temperature.<ref>[https://tshaonline.org/handbook/online/articles/dqr01 Refrigeration], Texas State Historical Association.</ref>\n\n[[File:SS Dunedin by Frederick Tudgay.JPG|thumb|left|[[Dunedin (ship)|''Dunedin'']], the first commercially successful refrigerated ship.]]\nThe new refrigerating technology first met with widespread industrial use as a means to freeze meat supplies for transport by sea in [[reefer ship]]s from the British [[Dominion]]s and other countries to the [[British Isles]]. The first to achieve this breakthrough was an entrepreneur who had emigrated to [[New Zealand]]. [[William Soltau Davidson]] thought that Britain's rising population and meat demand could mitigate the slump in world [[wool]] markets that was heavily affecting New Zealand. After extensive research, he commissioned the [[Dunedin (ship)|''Dunedin'']] to be refitted with a compression refrigeration unit for meat shipment in 1881. On February 15, 1882, the ''Dunedin'' sailed for London with what was to be the first commercially successful refrigerated shipping voyage, and the foundation of the refrigerated [[meat industry]].<ref>{{cite book|title=A lasting Legacy \u2013 A 125 year history of New Zealand Farming since the first Frozen Meat Shipment|author=Colin Williscroft|publisher=NZ Rural Press Limited|year=2007|url=https://books.google.com/books?id=VTrmMQAACAAJ}}</ref>\n\n''[[The Times]]'' commented "Today we have to record such a triumph over physical difficulties, as would have been incredible, even unimaginable, a very few days ago...". The ''[[Marlborough (1876 ship)|Marlborough]]''\u2014sister ship to the ''Dunedin'' \u2013 was immediately converted and joined the trade the following year, along with the rival [[New Zealand Shipping Company]] vessel ''Mataurua'', while the German Steamer ''Marsala'' began carrying frozen New Zealand lamb in December 1882. Within five years, 172 shipments of frozen meat were sent from New Zealand to the United Kingdom, of which only 9 had significant amounts of meat condemned. Refrigerated shipping also led to a broader meat and dairy boom in [[Australasia]] and South America. [[J & E Hall]] of [[Dartford]], England outfitted the 'SS Selembria' with a vapor compression system to bring 30,000 carcasses of [[mutton]] from the [[Falkland Islands]] in 1886.<ref>{{Cite web|url=http://www.jehall.com/about-jeh-group/history|title=Our History | Refrigeration Solutions | J&E Hall|website=www.jehall.com}}</ref> In the years ahead, the industry rapidly expanded to Australia, Argentina and the United States.\n\nBy the 1890s refrigeration played a vital role in the distribution of food. The meat-packing industry relied heavily on natural ice in the 1880s and continued to rely on manufactured ice as those technologies became available.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=142|edition=1st Harvard University Press pbk.}}</ref> By 1900, the meat-packing houses of Chicago had adopted ammonia-cycle commercial refrigeration. By 1914 almost every location used artificial refrigeration. The [[Meat packing industry#Meatpackers|major meat packers]], Armour, Swift, and Wilson, had purchased the most expensive units which they installed on train cars and in branch houses and storage facilities in the more remote distribution areas.\n\nBy the middle of the 20th century, refrigeration units were designed for installation on trucks or lorries. Refrigerated vehicles are used to transport perishable goods, such as frozen foods, fruit and vegetables, and temperature-sensitive chemicals. Most modern refrigerators keep the temperature between \u201340 and \u201320 \u00b0C, and have a maximum payload of around 24,000 kg gross weight (in Europe).\n\nAlthough commercial refrigeration quickly progressed, it had limitations that prevented it from moving into the household. First, most refrigerators were far too large. Some of the commercial units being used in 1910 weighed between five and two hundred tons. Second, commercial refrigerators were expensive to produce, purchase, and maintain. Lastly, these refrigerators were unsafe. It was not uncommon for commercial refrigerators to catch fire, explode, or leak toxic gases. Refrigeration did not become a household technology until these three challenges were overcome.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=38|edition=1st Harvard University Press pbk.}}</ref>\n\n [[File:Early household refrigerator in Popular Science 1919.png|thumb|An early example of the [[consumerization]] of mechanical refrigeration that began in the early 20th century. The [[refrigerant]] was [[sulfur dioxide]].]]\n[[File:Food into a refrigerator - 20111002.jpg|thumb|A modern home refrigerator]]\n\nDuring the early 1800s consumers preserved their food by storing food and ice purchased from ice harvesters in iceboxes. In 1803, Thomas Moore patented a metal-lined butter-storage tub which became the prototype for most iceboxes. These iceboxes were used until nearly 1910 and the technology did not progress. In fact, consumers that used the icebox in 1910 faced the same challenge of a moldy and stinky icebox that consumers had in the early 1800s.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=23, 38|edition=1st Harvard University Press pbk.}}</ref>\n\nGeneral Electric (GE) was one of the first companies to overcome these challenges. In 1911 GE released a household refrigeration unit that was powered by gas. The use of gas eliminated the need for an electric compressor motor and decreased the size of the refrigerator. However, electric companies that were customers of GE did not benefit from a gas-powered unit. Thus, GE invested in developing an electric model. In 1927, GE released the Monitor Top, the first refrigerator to run on electricity.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=43\u201345|edition=1st Harvard University Press pbk.}}</ref>\n\nIn 1930, Frigidaire, one of GE's main competitors, synthesized [[Freon]].<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=44|edition=1st Harvard University Press pbk.}}</ref> With the invention of synthetic refrigerants based mostly on a chlorofluorocarbon (CFC) chemical, safer refrigerators were possible for home and consumer use. Freon led to the development of smaller, lighter, and cheaper refrigerators. The average price of a refrigerator dropped from $275 to $154 with the synthesis of Freon. This lower price allowed ownership of refrigerators in American households to exceed 50%.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=45|edition=1st Harvard University Press pbk.}}</ref> Freon is a trademark of the DuPont Corporation and refers to these CFCs, and later hydro chlorofluorocarbon (HCFC) and hydro fluorocarbon (HFC), refrigerants developed in the late 1920s. These refrigerants were considered at the time to be less harmful than the commonly-used refrigerants of the time, including methyl formate, ammonia, methyl chloride, and sulfur dioxide. The intent was to provide refrigeration equipment for home use without danger. These CFC refrigerants answered that need. In the 1970s, though, the compounds were found to be reacting with atmospheric ozone, an important protection against solar ultraviolet radiation, and their use as a refrigerant worldwide was curtailed in the [[Montreal Protocol]] of 1987."}},
{"article_title": "Telemetry", "pageid": "46256", "revid": "1061697851", "timestamp": "2021-12-23T09:44:38Z", "history_paths": [["Telemetry --- Introduction ---", "History"]], "categories": ["telemetry", "telecommunications", "measurement", "spaceflight technology"], "heading_tree": {"Telemetry --- Introduction ---": {"History": {"Types of telemeter": {}}, "Applications": {"Meteorology": {}, "Oil and gas industry": {}, "Motor racing": {}, "Transportation": {}, "Agriculture": {}, "Water management": {}, "{{anchor|Defense, space and resource exploration systems}}Defense, space and resource exploration": {"Space science": {}, "Rocketry": {}, "{{anchor|Flight test}}Flight testing": {}, "{{anchor|Enemy intelligence}}Military intelligence": {}}, "Energy monitoring": {}, "Resource distribution": {"Dry goods": {}, "Fluids": {}, "Bulk solids": {}}, "Medicine/healthcare": {}, "{{anchor|Fisheries and wildlife research and management}}Fishery and wildlife research and management": {}, "{{anchor|Retail businesses}}Retail": {}, "Law enforcement": {}, "{{anchor|Electrical energy providers}}Energy providers": {}, "Falconry": {}, "Testing": {}, "Communications": {}, "Mining": {}, "Software": {}}, "International standards": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Telemetry --- Introduction ---|History": "The beginning of industrial telemetry lies in the [[Steam power during the Industrial Revolution|steam age]], although the sensor was not called ''telemeter'' at that time.<ref name=Kopp>Brian Kopp, "Industrial telemetry", in ''Telemetry Systems Engineering'', pages 493-524, Artech House, 2002 {{ISBN|1580532578}}.</ref> Examples are [[James Watt]]'s (1736-1819) additions to his steam engines for monitoring from a (near) distance such as the [[mercury pressure gauge]] and the [[fly-ball governor]].<ref name=Kopp/>\n\nAlthough the original telemeter referred to a ranging device (the [[rangefinding telemeter]]), by the late 19th century the same term had been in wide use by electrical engineers applying it refer to electrically operated devices measuring many other quantities besides distance (for instance, in the patent of an "Electric Telemeter Transmitter"<ref>{{cite patent| country = US| number = 490012| status= patent\n| title\t= Electric Telemeter Transmitter.| gdate = 1893-01-17| fdate = 1891-11-21| inventor = Fernando J. Dibble| url = https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=US&NR=490012A&KC=A&FT=D&ND=&date=18930117&DB=&locale=#}}</ref>). General telemeters included such sensors as the [[thermocouple]] (from the work of [[Thomas Johann Seebeck]]), the [[resistance thermometer]] (by [[William Siemens]] based on the work of [[Humphry Davy]]), and the electrical [[strain gauge]] (based on [[Lord Kelvin]]'s discovery that conductors under mechanical strain change their [[electrical resistance|resistance]]) and output devices such as [[Samuel Morse]]'s [[telegraph sounder]] and the [[relay]]. In 1889 this led an author in the [[Institution of Civil Engineers]] proceedings to suggest that the term for the rangefinder telemeter might be replaced with [[tacheometer]].<ref>"The term telemeter, which was introduced by surveyors, has been appropriated to so great an extent by electricians, that it is likely to be abandoned by the former for the term tacheometer." (p.207), {{cite journal|last1=Gribble|first1=T G|title=Preliminary Survey in New Countries, as Exemplified in the Survey of Windward Hawaii. (Includes Appendices)|journal=Minutes of the Proceedings of the Institution of Civil Engineers|volume=95|issue=1889|year=1889|pages=195\u2013208|issn=1753-7843|doi=10.1680/imotp.1889.20841|url=https://zenodo.org/record/2331506}}</ref>\n\nIn the 1930s use of electrical telemeters grew rapidly. The electrical strain gauge was widely used in rocket and aviation research and the [[radiosonde]] was invented for [[meteorological]] measurements. The advent of [[World War II]] gave an impetus to industrial development and henceforth many of these telemeters became commercially viable.<ref>Kopp, page 497</ref>\n\nCarrying on from rocket research, radio telemetry was used routinely as space exploration got underway.  Spacecraft are in a place where a physical connection is not possible, leaving radio or other electromagnetic waves (such as infrared lasers) as the only viable option for telemetry. During crewed space missions it is used to monitor not only parameters of the vehicle, but also the health and life support of the astronauts.<ref>Sunny Tsiao, ''Read You Loud and Clear: The Story of NASA's Spaceflight Tracking and Data Network'', Government Printing Office, 2008 {{ISBN|0160801915}}.</ref> During the [[Cold War]] telemetry found uses in espionage. US intelligence found that they could monitor the telemetry from [[Soviet Union|Soviet]] missile tests by building a telemeter of their own to intercept the radio signals and hence learn a great deal about Soviet capabilities.<ref>MacKenzie, *Donald MacKenzie, "The Soviet Union and strategic missile guidance", in ''Soviet Military Policy: An International Security Reader'', MIT Press, 1989 {{ISBN|0262620669}}.</ref>\n\n Telemeters are the physical devices used in telemetry.  It consists of a [[sensor]], a transmission path, and a display, recording, or control device.  Electronic devices are widely used in telemetry and can be [[wireless]] or hard-wired, [[analog signal|analog]] or [[Digital data|digital]]. Other technologies are also possible, such as mechanical, hydraulic and optical.<ref>K.A.Bakshi A.V.Bakshi U.A.Bakshi, ''Electronic Measurements'', Technical Publications, 2008 {{ISBN|8184313918}}.</ref>\n\nTelemetering information over wire had its origins in the 19th century. One of the first data-transmission circuits was developed in 1845 between the [[Tsardom of Russia|Russian Tsar]]'s [[Winter Palace]] and army headquarters. In 1874, French engineers built a system of weather and snow-depth sensors on [[Mont Blanc]] that transmitted real-time information to [[Paris]]. In 1901 the American inventor C. Michalke patented the [[Synchro|selsyn]], a circuit for sending synchronized rotation information over a distance. In 1906 a set of seismic stations were built with telemetering to the Pulkovo Observatory in Russia.  In 1912, [[Commonwealth Edison]] developed a system of telemetry to monitor electrical loads on its power grid. The [[Panama Canal]] (completed 1913\u20131914) used extensive telemetry systems to monitor locks and water levels.<ref>Mayo-Wells, "The Origins of Space Telemetry", ''Technology and Culture'', 1963</ref>\n\nWireless telemetry made early appearances in the [[radiosonde]], developed concurrently in 1930 by Robert Bureau in France and [[Pavel Molchanov]] in [[Russia]].  Molchanov's system modulated temperature and pressure measurements by converting them to wireless [[Morse code]]. The German [[V-2]] rocket used a system of primitive multiplexed radio signals called "Messina" to report four rocket parameters, but it was so unreliable that [[Wernher von Braun]] once claimed it was more useful to watch the rocket through binoculars.\n\nIn the US and the USSR, the Messina system was quickly replaced with better systems; in both cases, based on [[pulse-position modulation]] (PPM).<ref>Joachim & Muehlner, "Trends in Missile and Space Radio Telemetry" declassified Lockheed report</ref>\nEarly Soviet missile and space telemetry systems which were developed in the late 1940s used either PPM (e.g., the Tral telemetry system developed by OKB-MEI) or [[pulse-duration modulation]] (e.g., the RTS-5 system developed by NII-885).  In the United States, early work employed similar systems, but were later replaced by [[pulse-code modulation]] (PCM) (for example, in the Mars probe [[Mariner 4]]).  Later Soviet interplanetary probes used redundant radio systems, transmitting telemetry by PCM on a decimeter band and PPM on a centimeter band.<ref>Molotov, E. L., ''Nazemnye Radiotekhnicheskie Sistemy Upravleniya Kosmicheskiymi Apparatami''</ref>"}},
{"article_title": "Automated teller machine", "pageid": "46628", "revid": "1062209317", "timestamp": "2021-12-27T01:29:21Z", "history_paths": [["Automated teller machine --- Introduction ---", "History"]], "categories": ["automated teller machines", "computer-related introductions in 1967", "automation", "banking equipment", "banking technology", "embedded systems", "american inventions", "english inventions", "payment systems", "articles containing video clips", "1967 in economics", "20th-century inventions"], "heading_tree": {"Automated teller machine --- Introduction ---": {"History": {"Propagation": {}, "Docutel in the United States": {}, "Further advances": {}}, "Location": {}, "Financial networks": {}, "Global use": {}, "Hardware": {}, "Software": {}, "Impact on labor": {}, "Security": {"Physical": {}, "Transactional secrecy and integrity": {}, "Customer identity integrity": {}, "Device operation integrity": {}, "Customer security": {}, "Jackpotting": {}, "Encryption": {}}, "Uses": {}, "Reliability": {}, "Fraud": {"Card fraud": {}}, "Related devices": {}, "See also": {}, "References": {}, "Further reading": {"Primary sources": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Automated teller machine --- Introduction ---|History": "[[File:Fr\u00fcher Bankautomat von Nixdorf.jpg|thumb|left|An old [[Nixdorf Computer AG|Nixdorf]] ATM]]\n\nThe idea of out-of-hours cash distribution developed from bankers' needs in Japan, Sweden, \nand the United Kingdom.<ref name="Atlantic">{{cite magazine|title=A Brief History of the ATM|url=https://www.theatlantic.com/technology/archive/2015/03/a-brief-history-of-the-atm/388547/|magazine=The Atlantic|access-date=26 April 2015|date=26 March 2015|url-status=live|archive-url=https://web.archive.org/web/20150428065642/http://www.theatlantic.com/technology/archive/2015/03/a-brief-history-of-the-atm/388547/|archive-date=28 April 2015}}</ref><ref>{{cite web|url=https://www.bloomberg.com/opinion/articles/2013-03-27/how-the-atm-revolutionized-the-banking-business |first=Bernardo |last=Batiz-Lazo|title=How the ATM Revolutionized the Banking Business|publisher=[[Bloomberg L.P.|Bloomberg]]|date=27 March 2013|url-status=live|archive-url=https://web.archive.org/web/20140209154037/http://www.bloomberg.com/news/2013-03-27/how-the-atm-revolutionized-the-banking-business.html|archive-date=9 February 2014}}</ref><ref>{{cite web |url=https://www.atmia.com/files/50th%20Anniversary/50th_ATM_Anniversary_Fact_Sheet_-_06272016.pdf |title=ATMIA 50th Anniversary Factsheet |author=<!--Staff writer(s); no by-line.--> |date=October 2015 |website=www.atmia.com |publisher=ATM Industry Association |access-date=29 June 2016 |url-status=live |archive-url=https://web.archive.org/web/20160818110157/https://www.atmia.com/files/50th%20Anniversary/50th_ATM_Anniversary_Fact_Sheet_-_06272016.pdf |archive-date=18 August 2016 }}</ref> A Japanese device called the "Computer Loan Machine" supplied cash as a three-month loan at 5% p.a. after inserting a credit card. The device was operational in 1966.<ref>'Fast Machine With a Buck',"Pacific Star and Stripes", 7 July 1966</ref><ref>'Instant Cash with a Credit Card', "ABA Banking Journal", January 1967</ref> However, little is known about the device.<ref name="Atlantic"/>\n\nAdrian Ashfield invented the basic idea of a card combining the key and user's identity in February 1962. This was granted UK Patent 959,713 for "Access Controller" in June 1964 and assigned to W. S. Atkins & Partners who employed Ashfield. He was paid ten shillings for this, the standard sum for all patents. It was originally intended to dispense petrol but the patent covered all uses.{{citation needed|date=December 2018}}\n\nIn the US patent record, [[Luther George Simjian]] has been credited with developing a "prior art device". Specifically, his 132nd patent (US3079603), which was first filed on 30 June 1960 (and granted 26 February 1963). The roll-out of this machine, called Bankograph, was delayed by a couple of years, due in part to Simjian's Reflectone Electronics Inc. being acquired by Universal Match Corporation.<ref>"Universal Match Maps Acquisition", ''The New York Times'', 22 March 1961</ref> An experimental Bankograph was installed in [[New York City]] in 1961 by the [[Citibank|City Bank of New York]], but removed after six months due to the lack of customer acceptance. The Bankograph was an automated envelope deposit machine (accepting coins, cash and cheques) and did not have cash dispensing features.<ref>"Machine Accepts Bank Deposits", ''The New York Times'', 12 April 1961</ref><ref>{{cite web|url=http://www.atmmarketplace.com/article/217157/From-punchcard-to-prestaging-50-years-of-ATM-innovation |title=From punchcard to prestaging: 50 years of ATM innovation |publisher=ATM Marketplace |date=31 July 2013 |access-date=27 September 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130815222832/http://www.atmmarketplace.com/article/217157/From-punchcard-to-prestaging-50-years-of-ATM-innovation |archive-date=15 August 2013 }}</ref>\n\n[[File:RegVarneyATM.jpg|thumb|Actor [[Reg Varney]] using the world's first cash machine in [[Enfield Town]], north London on 27 June 1967]]\n\nA cash machine was put into use by [[Barclays Bank]] in its [[Enfield Town]] branch in [[North London]], United Kingdom, on 27 June 1967.<ref>{{cite web|last1=Batiz-Lazo|first1=Bernardo|last2=Reid|first2=Robert J. K.|title=Evidence from the Patent Record on the Development of Cash Dispensing Technology|url=http://mpra.ub.uni-muenchen.de/9461/1/MPRA_paper_9461.pdf|publisher=Munich Personal RePEc Archive|access-date=27 April 2015|date=30 June 2008|page=4|url-status=live|archive-url=https://web.archive.org/web/20150904045127/https://mpra.ub.uni-muenchen.de/9461/1/MPRA_paper_9461.pdf|archive-date=4 September 2015}}</ref> This machine was inaugurated by English comedy actor [[Reg Varney]].<ref>{{cite web | url = http://www.bbc.co.uk/london/content/articles/2007/06/26/cash_machine_feature.shtml | title = Enfield's cash gift to the world | publisher = [[BBC London]] | date = 27 June 2007 | url-status = live | archive-url = https://web.archive.org/web/20151103030534/http://www.bbc.co.uk/london/content/articles/2007/06/26/cash_machine_feature.shtml | archive-date = 3 November 2015 }}</ref> This instance of the invention is credited to the engineering team led by [[John Shepherd-Barron]] of printing firm [[De La Rue]],<ref name=milligan>{{cite news | url = http://news.bbc.co.uk/2/hi/business/6230194.stm | title = The man who invented the cash machine | work = BBC News | date = 25 June 2007 | access-date = 26 April 2010 | first = Brian | last = Milligan | url-status = live | archive-url = https://web.archive.org/web/20091226192112/http://news.bbc.co.uk/2/hi/business/6230194.stm | archive-date = 26 December 2009 }}</ref> who was awarded an [[Order of the British Empire|OBE]] in the [[2005 New Year Honours]].<ref>{{cite news| url = http://news.bbc.co.uk/2/hi/uk_news/scotland/4135269.stm | title = ATM inventor honoured | work = BBC News | date=31 December 2004 | access-date=26 April 2010| archive-url= https://web.archive.org/web/20100608040555/http://news.bbc.co.uk/2/hi/uk_news/scotland/4135269.stm| archive-date= 8 June 2010 | url-status= live}}</ref><ref name="Networld Media Group">{{cite book |first1=Tom |last1=Harper |first2=Bernardo |last2=Batiz-Lazo |title= Cash Box: The Invention and Globalization of the ATM |publisher= Networld Media Group |date=2013 |isbn=978-1935497622}}</ref> Transactions were initiated by inserting paper cheques issued by a teller or cashier, marked with [[carbon-14]] for machine readability and security, which in a later model were matched with a six-digit [[personal identification number]] (PIN).<ref name=milligan/><ref name="latimes1">{{cite news | title = ATM inventor John Shepherd-Barron dies at age of 84 on 20th May 2010 | newspaper = Los Angeles Times| url = http://latimesblogs.latimes.com/afterword/2010/05/atm-inventor-john-shepherdbarron-dies-at-84.html | date = 19 May 2010 | url-status = live | archive-url = https://web.archive.org/web/20100523172520/http://latimesblogs.latimes.com/afterword/2010/05/atm-inventor-john-shepherdbarron-dies-at-84.html | archive-date = 23 May 2010 }}</ref> Shepherd-Barron stated "It struck me there must be a way I could get my own money, anywhere in the world or the UK. I hit upon the idea of a chocolate bar dispenser, but replacing chocolate with cash."<ref name=milligan/>\n\nThe Barclays\u2013De La Rue machine (called De La Rue Automatic Cash System or DACS)<ref>Mary Bellis. [http://inventors.about.com/od/astartinventions/a/atm_2.htm "The ATM of John Shepherd Barron"]. [[About.com]]. Retrieved 2011-04-29.</ref> beat the [[List of banks in Sweden|Swedish saving banks]]' and a company called Metior's machine (a device called Bankomat) by a mere nine days and [[National Westminster Bank|Westminster Bank's]]\u2013[[Smiths Group|Smith Industries]]\u2013[[Chubb Locks|Chubb]] system (called Chubb MD2) by a month.<ref>{{cite journal | url = https://ideas.repec.org/p/pra/mprapa/3689.html | title = The emergence and evolution of ATM networks in the UK, c. 1967\u20132000 | author = B. Batiz-Lazo | date = June 2007 | publisher = Business History, 2009 (51:1). Taylor and Francis, 2009. | url-status = live | archive-url = https://web.archive.org/web/20141103165250/https://ideas.repec.org/p/pra/mprapa/3689.html | archive-date = 3 November 2014 }}</ref> The online version of the Swedish machine is listed to have been operational on 6 May 1968, while claiming to be the first online ATM in the world, ahead of similar claims by [[IBM]] and [[Lloyds Banking Group|Lloyds Bank]] in 1971,<ref>{{cite journal | url = http://www.ebhsoc.org/journal/index.php/journal/article/view/274 | title = The origins of the cashless society: cash dispensers, direct to account payments and the development of on-line real-time networks, c. 1965\u20131985 | journal = Essays in Economic & Business History | volume = 32 | pages = 100\u2013137 | author = B. Batiz-Lazo, T. Karlsson and B. Thodenius | publisher = Essays in Economic and Business History, 2014 (32). The Economic and Business History Society, 2014. | url-status = live | archive-url = https://web.archive.org/web/20140714184815/http://www.ebhsoc.org/journal/index.php/journal/article/view/274 | archive-date = 14 July 2014 |date=24 April 2014 }}</ref> and [[OKI (company)|Oki]] in 1970.<ref>{{cite web |title=Automated Teller Terminal AT-20P |url=http://museum.ipsj.or.jp/en/heritage/AT-20P.html |website=IPSJ Computer Museum |publisher=[[Information Processing Society of Japan]] |access-date=22 July 2019}}</ref> The collaboration of a small start-up called Speytec and [[Midland Bank]] developed a fourth machine which was marketed after 1969 in Europe and the US by the [[Burroughs Corporation]]. The patent for this device (GB1329964) was filed in September 1969 (and granted in 1973) by John David Edwards, Leonard Perkins, John Henry Donald, Peter Lee Chappell, Sean Benjamin Newcombe, and Malcom David Roe.\n\nBoth the DACS and MD2 accepted only a single-use token or voucher which was retained by the machine, while the Speytec worked with a card with a magnetic stripe at the back. They used principles including [[radiation|Carbon-14]] and low-coercivity [[magnetism]] in order to make fraud more difficult.\n\n[[File:\u0411\u0430\u043d\u043a\u043e\u043c\u0430\u0442 \u0421\u0431\u0435\u0440\u0431\u0430\u043d\u043a\u0430.jpg|thumb|left|[[Sberbank of Russia|Sberbank]] ATM in [[Tolyatti]], [[Russia]]]]\n\nThe idea of a [[Personal identification number|PIN]] stored on the card was developed by a group of engineers working at [[Smiths Group]] on the Chubb MD2 in 1965 and which has been credited to [[James Goodfellow]]<ref>{{cite web|url=https://www.bbc.co.uk/programmes/b013n554|title=James Goodfellow, Series 2, Pioneers - BBC Radio 4 Extra|website=BBC|access-date=29 March 2018}}</ref> (patent GB1197183 filed on 2 May 1966 with Anthony Davies). The essence of this system was that it enabled the verification of the customer with the debited account without human intervention. This patent is also the earliest instance of a complete "currency dispenser system" in the patent record. This patent was filed on 5 March 1968 in the US (US 3543904) and granted on 1 December 1970. It had a profound influence on the industry as a whole. Not only did future entrants into the cash dispenser market such as [[NCR Corporation]] and [[IBM]] licence Goodfellow's PIN system, but a number of later patents reference this patent as "Prior Art Device".<ref>{{cite journal | url = https://ideas.repec.org/p/pra/mprapa/9461.html | title = Evidence from the patent record on the development of cash dispensing technology | author = B. Batiz-Lazo and R. J. K. Reid | publisher = History of Telecommunications Conference, 2008. Histelcon 2008. IEEE | url-status = live | archive-url = https://web.archive.org/web/20141103165602/https://ideas.repec.org/p/pra/mprapa/9461.html | archive-date = 3 November 2014 | date = 30 June 2008 }}</ref>\n\n Devices designed by British (i.e. Chubb, De La Rue) and Swedish (i.e. Asea Meteor) quickly spread out. For example, given its link with [[Barclays]], [[Bank of Scotland]] deployed a DACS in 1968 under the  [http://www.lloydsbankinggroup.com/our-group/our-heritage/timeline/1951-1990/ 'Scotcash'] brand. Customers were given personal code numbers to activate the machines, similar to the modern PIN. They were also supplied with \u00a310 vouchers. These were fed into the machine, and the corresponding amount debited from the customer's account.\n\nA Chubb-made ATM appeared in [[Sydney]] in 1969. This was the first ATM installed in [[Australia]]. The machine only dispensed $25 at a time and the bank card itself would be mailed to the user after the bank had processed the withdrawal.\n\n[[File:ABC ATMs.ogv|thumb|1969 [[Australian Broadcasting Corporation|ABC]] news report on the introduction of ATMs in [[Sydney, Australia]]. People could only receive [[Australian dollar|AUS $]]25 at a time and the bank card was sent back to the user at a later date. This was a Chubb machine]]\n\nAsea Metior's Bancomat was the first ATM installed in [[Spain]] on 9 January 1969, in central [[Madrid]] by [[Banesto]]. This device dispensed 1,000 [[Spanish peseta|peseta]] bills (1 to 5 max). Each user had to introduce a security personal key using a combination of the ten numeric buttons.<ref>{{cite web | url = http://hemeroteca.abc.es/nav/Navigate.exe/hemeroteca/madrid/abc/1969/01/09/048.html | title = Bancomat (In Spanish) | author = Marino Gomez-Santos | publisher = ABC | date = 9 January 1969 | url-status = live | archive-url = https://web.archive.org/web/20140811221708/http://hemeroteca.abc.es/nav/Navigate.exe/hemeroteca/madrid/abc/1969/01/09/048.html | archive-date = 11 August 2014 }}</ref> In March of the same year an ad with the instructions to use the Bancomat was published in the same newspaper.<ref>{{cite web | url = http://hemeroteca.abc.es/nav/Navigate.exe/hemeroteca/madrid/abc/1969/03/18/058.html | title = Bancomat Banesto (commercial ad with instructions for use in Spanish) | publisher = ABC | date = 18 March 1969 | url-status = live | archive-url = https://web.archive.org/web/20140811221714/http://hemeroteca.abc.es/nav/Navigate.exe/hemeroteca/madrid/abc/1969/03/18/058.html | archive-date = 11 August 2014 }}</ref>\n\n After looking firsthand at the experiences in Europe, in 1968 the ATM was pioneered in the U.S. by [[Donald Wetzel]], who was a department head at a company called Docutel.<ref name="Networld Media Group"/> Docutel was a subsidiary of Recognition Equipment Inc of [[Dallas]], [[Texas]], which was producing optical scanning equipment and had instructed Docutel to explore automated baggage handling and automated gasoline pumps.<ref>{{cite book |first=James |last=Essinger  |title= ATM Networks: Their Organization, Security and Future |publisher= Elsevier International |date=1987}}</ref>\n\nOn 2 September 1969, [[Chemical Bank]] installed a prototype ATM in the U.S. at its branch in [[Rockville Centre, New York]]. The first ATMs were designed to dispense a fixed amount of cash when a user inserted a specially coded card.<ref>{{cite book |first=Rob |last=Kirkpatrick |url=https://books.google.com/books?id=XZMrIchANY4C&pg=PA266 |title=1969: The Year Everything Changed |publisher=Skyhorse Publishing Inc. |date=2009 |page=266 |isbn=9781602393660 |url-status=live |archive-url=https://web.archive.org/web/20111225211738/http://books.google.com/books?id=XZMrIchANY4C&pg=PA266 |archive-date=25 December 2011 }}</ref> A Chemical Bank advertisement boasted "On Sept. 2 our bank will open at 9:00 and never close again."<ref>{{cite book |url=https://books.google.com/books?id=BtEDAAAAMBAJ&pg=PA84 |title=Popular Mechanics - Google Books |access-date=2011-02-11 |url-status=live |archive-url=https://web.archive.org/web/20111225214202/http://books.google.com/books?id=BtEDAAAAMBAJ&lpg=PA84&pg=PA84 |archive-date=25 December 2011 |publisher=Hearst Magazines |date=December 2005 }}</ref> Chemical's ATM, initially known as a Docuteller was designed by [[Donald Wetzel]] and his company Docutel. Chemical executives were initially hesitant about the electronic banking transition given the high cost of the early machines.  Additionally, executives were concerned that customers would resist having machines handling their money.<ref>{{cite web|url=http://americanhistory.si.edu/collections/comphist/wetzel.htm |title=Interview with Mr. Don Wetzel |publisher=Americanhistory.si.edu |access-date=2011-02-11| archive-url= https://web.archive.org/web/20110220214346/http://americanhistory.si.edu/collections/comphist/wetzel.htm| archive-date= 20 February 2011 | url-status= live}}</ref> In 1995, the [[Smithsonian National Museum of American History]] recognised Docutel and Wetzel as the inventors of the networked ATM.<ref>{{cite web|url=http://www.thocp.net/hardware/atm.htm |title=Automatic teller machine |publisher=Thocp.net |work=The History of Computing Project |date=17 April 2006 |access-date=2011-02-11| archive-url= https://web.archive.org/web/20110220215034/http://www.thocp.net/hardware/atm.htm| archive-date= 20 February 2011 | url-status= live}}</ref> To show confidence in Docutel, Chemical installed the first four production machines in a marketing test that proved they worked reliably, customers would use them and even pay a fee for usage. Based on this, banks around the country began to experiment with ATM installations.\n\nBy 1974, Docutel had acquired 70 percent of the U.S. market; but as a result of the early 1970s worldwide recession and its reliance on a single product line, Docutel lost its independence and was forced to merge with the U.S. subsidiary of [[Olivetti]].{{citation needed|date=September 2018}}\n\nIn 1973, Wetzel was granted [http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=3761682.PN.&OS=PN/3761682&RS=PN/3761682 U.S. Patent # 3,761,682]; the application had been filed in October 1971. However, the U.S. patent record cites at least three previous applications from Docutel, all relevant to the development of the ATM and where Wetzel does not figure, namely [http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=3662343.PN.&OS=PN/3662343&RS=PN/3662343 US Patent # 3,662,343], [http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=3651976.PN.&OS=PN/3651976&RS=PN/3651976 U.S. Patent # 3651976] and [http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=368569.PN.&OS=PN/368569&RS=PN/368569 U.S. Patent # 3,68,569]. These patents are all credited to Kenneth S. Goldstein, MR Karecki, TR Barnes, GR Chastian and John D. White.\n[[File:A person uses an ATM at Chase Bank, NYC - 2008.tif|thumb|[[Chase Bank]] ATM - 2008]]\n\n In April 1971, [[Busicom]] began to manufacture ATMs based on the first commercial [[microprocessor]], the [[Intel 4004]]. Busicom manufactured these microprocessor-based automated teller machines for several buyers, with [[NCR Corporation]] as the main customer.<ref>{{cite journal |last1=Aspray |first1=W. |s2cid=15782735 |title=The Intel 4004 microprocessor: what constituted invention? |journal=IEEE Annals of the History of Computing |date=1997 |volume=19 |issue=3 |pages=4\u201315 |doi=10.1109/85.601727 |issn=1058-6180}}</ref>\n\n[[Mohamed Atalla]] invented the first [[hardware security module]] (HSM),<ref name="Stiennon">{{cite web |last1=Stiennon |first1=Richard |title=Key Management a Fast Growing Space |url=https://securitycurrent.com/key-management-a-fast-growing-space/ |website=SecurityCurrent |publisher=IT-Harvest |access-date=21 August 2019 |date=17 June 2014}}</ref> dubbed the "Atalla Box", a security system which encrypted [[Personal identification number|PIN]] and ATM messages, and protected offline devices with an un-guessable PIN-generating key.<ref name="Lazo">{{cite book |last1=B\u00e1tiz-Lazo |first1=Bernardo |title=Cash and Dash: How ATMs and Computers Changed Banking |date=2018 |publisher=[[Oxford University Press]] |isbn=9780191085574 |pages=284 & 311 |url=https://books.google.com/books?id=rWhiDwAAQBAJ&pg=PA284}}</ref> In March 1972, Atalla filed {{US patent|3938091}} for his PIN verification system, which included an encoded [[card reader]] and described a system that utilized [[encryption]] techniques to assure telephone link security while entering personal ID information that was transmitted to a remote location for verification.<ref name="nist">{{cite web |title=The Economic Impacts of NIST's Data Encryption Standard (DES) Program |url=https://www.nist.gov/sites/default/files/documents/2017/05/09/report01-2.pdf |website=[[National Institute of Standards and Technology]] |publisher=[[United States Department of Commerce]] |date=October 2001 |access-date=21 August 2019}}</ref>\n\nHe founded [[Atalla Corporation]] (now [[Utimaco Atalla]]) in 1972,<ref name="Langford">{{cite web |last1=Langford |first1=Susan |title=ATM Cash-out Attacks |url=https://h41382.www4.hpe.com/gfs-shared/20140318153228.pdf |website=[[Hewlett Packard Enterprise]] |publisher=[[Hewlett-Packard]] |year=2013 |access-date=21 August 2019}}</ref> and commercially launched the "Atalla Box" in 1973.<ref name="Lazo"/> The product was released as the Identikey. It was a card reader and [[Identity verification service|customer identification system]], providing a terminal with [[plastic card]] and PIN capabilities. The Identikey system consisted of a card reader console, two customer [[PIN pad]]s, intelligent controller and built-in electronic interface package.<ref name="Computerworld1978">{{cite journal |title=ID System Designed as NCR 270 Upgrade |journal=[[Computerworld]] |date=13 February 1978 |volume=12 |issue=7 |page=49 |url=https://books.google.com/books?id=fB-Te8d5hO8C&pg=PA49 |publisher=IDG Enterprise}}</ref> The device consisted of two [[keypads]], one for the customer and one for the teller. It allowed the customer to type in a secret code, which is transformed by the device, using a microprocessor, into another code for the teller.<ref name="Computerworld1976">{{cite journal |title=Four Products for On-Line Transactions Unveiled |journal=[[Computerworld]] |date=26 January 1976 |volume=10 |issue=4 |page=3 |url=https://books.google.com/books?id=3u9H-xL4sZAC&pg=PA3 |publisher=IDG Enterprise}}</ref> During a [[Financial transaction|transaction]], the customer's [[Bank card number|account number was read by the card reader]]. This process replaced manual entry and avoided possible key stroke errors. It allowed users to replace traditional customer verification methods such as signature verification and test questions with a secure PIN system.<ref name="Computerworld1978"/> The success of the "Atalla Box" led to the wide adoption of hardware security modules in ATMs.<ref>{{cite book |last1=B\u00e1tiz-Lazo |first1=Bernardo |title=Cash and Dash: How ATMs and Computers Changed Banking |date=2018 |publisher=[[Oxford University Press]] |isbn=9780191085574 |page=311 |url=https://books.google.com/books?id=rWhiDwAAQBAJ&pg=PA311}}</ref> Its PIN verification process was similar to the later [[IBM 3624]].<ref>{{cite journal |last1=Konheim |first1=Alan G. |s2cid=1706990 |title=Automated teller machines: their history and authentication protocols |journal=Journal of Cryptographic Engineering |date=1 April 2016 |volume=6 |issue=1 |pages=1\u201329 |doi=10.1007/s13389-015-0104-3 |url=https://slideheaven.com/automated-teller-machines-their-history-and-authentication-protocols.html |issn=2190-8516 |access-date=22 July 2019 |archive-url=https://web.archive.org/web/20190722030759/https://slideheaven.com/automated-teller-machines-their-history-and-authentication-protocols.html |archive-date=22 July 2019 |url-status=dead }}</ref> Atalla's HSM products protect 250{{nbsp}}million [[Card Transaction Data|card transactions]] every day as of 2013,<ref name="Langford"/> and secure the majority of the world's ATM transactions as of 2014.<ref name="Stiennon"/>\n\nThe IBM 2984 was a modern ATM and came into use at Lloyds Bank, High Street, Brentwood, Essex, the UK in December 1972. The IBM 2984 was designed at the request of [[Lloyds Bank (historic)|Lloyds Bank]]. The 2984 Cash Issuing Terminal was a true ATM, similar in function to today's machines and named by Lloyds Bank: Cashpoint. Cashpoint is still a [[registered trademark]] of Lloyds Banking Group in the UK but is often used as a [[List of generic and genericized trademarks|generic trademark]] to refer to ATMs of all UK banks. All were online and issued a variable amount which was immediately deducted from the account. A small number of 2984s were supplied to a U.S. bank. A couple of well known historical models of ATMs include the [[Atalla Corporation|Atalla Box]],<ref name="Lazo"/> IBM 3614, [[IBM 3624]] and 473x series, [[Diebold 10xx]] and TABS 9000 series, NCR 1780 and earlier NCR 770 series.\n\nThe first switching system to enable shared automated teller machines between banks went into production operation on 3 February 1979, in Denver, Colorado, in an effort by Colorado National Bank of Denver and Kranzley and Company of Cherry Hill, New Jersey.<ref>personal knowledge of William Patterson who was there supporting the network</ref>\n\nIn 2012, a new ATM at [[Royal Bank of Scotland]] allowed customers to withdraw cash up to \u00a3130 without a card by inputting a six-digit code requested through their smartphones.<ref>{{cite news |url=https://www.bbc.co.uk/news/business-18409560 |title=ATMs to operate without a card |date=12 June 2012 |work=BBC News |url-status=live |archive-url=https://web.archive.org/web/20120613035141/http://www.bbc.co.uk/news/business-18409560 |archive-date=13 June 2012  }}</ref>"}},
{"article_title": "Chroma key", "pageid": "46953", "revid": "1061889429", "timestamp": "2021-12-24T17:19:08Z", "history_paths": [["Chroma key --- Introduction ---", "History"]], "categories": ["film and video technology", "television terminology", "film and video terminology"], "heading_tree": {"Chroma key --- Introduction ---": {"History": {"Predecessors": {}, "Bluescreen": {}}, "Process": {"Processing a green backdrop": {}, "Processing a blue backdrop": {}, "Major factors": {"Lighting": {}, "Camera": {}}}, "Clothing": {}, "Background colour": {}, "Tolerances": {"Even lighting": {}, "Exposure": {}}, "Programming": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Chroma key --- Introduction ---|History": "Prior to the introduction of [[Matte (filmmaking)|travelling mattes]] and [[optical printer|optical printing]], [[double exposure]] was used to introduce elements into a scene which were not present in the initial exposure. This was done using black draping where a green screen would be used today. [[George Albert Smith (film pioneer)|George Albert Smith]] first used this approach in 1898. In 1903, ''[[The Great Train Robbery (1903 film)|The Great Train Robbery]]'' by [[Edwin Stanton Porter|Edwin S. Porter]] used double exposure to add background scenes to windows which were black when filmed on set, using a [[garbage matte]] to expose only the window areas.<ref>{{cite book | title=Experimental Filmmaking: Break the Machine | author=Kathryn Ramey | page=70 | url=https://books.google.com/books?id=XYRICgAAQBAJ&pg=PA70| isbn=9781136071508 | date=2015-07-30 }}</ref>\n\nIn order to have figures in one exposure actually move in front of a substituted background in the other, a travelling matte was needed, to occlude the correct portion of the background in each frame. In 1918 [[Frank D. Williams (cinematographer)|Frank Williams]] patented a travelling matte technique, again based on using a black background. This was used in many films, such as ''[[The Invisible Man (1933 film)|The Invisible Man]]''.<ref name=Foster />{{rp|4}}\n\nIn the 1920s, [[Walt Disney]] used a white backdrop to include human actors with cartoon characters and backgrounds in his ''[[Alice Comedies]]''.<ref name=Foster />{{rp|5}}\n\n The blue screen method was developed in the 1930s at [[RKO Radio Pictures]].  At RKO, [[Linwood Dunn]] used an early version of the [[Matte (filmmaking)|travelling matte]] to create "wipes" \u2013 where there were transitions like a windshield wiper in films such as ''[[Flying Down to Rio]]'' (1933). Credited to [[Lawrence W. Butler|Larry Butler]], a scene featuring a genie escaping from a bottle was the first use of a proper bluescreen process to create a traveling matte for ''[[The Thief of Bagdad (1940 film)|The Thief of Bagdad]]'' (1940), which won the [[Academy Award for Best Visual Effects|Academy Award for Best Special Effects]] that year. In 1950, [[Warner Brothers]] employee and ex-[[Kodak]] researcher [[Arthur Widmer]] began working on an [[ultraviolet]] travelling matte process. He also began developing bluescreen techniques: one of the first films to use them was the [[The Old Man and the Sea (1958 film)|1958 adaptation]] of the [[Ernest Hemingway]] novella, ''[[The Old Man and the Sea]]'', starring [[Spencer Tracy]].<ref name="cri">{{cite web|url=http://en.chinabroadcast.cn/2246/2005-2-14/90@206385.htm|title=Illusions Take Home First Oscars|date=14 February 2005|publisher=[[China Radio International|CRI English]]|access-date=21 January 2009|archive-url=https://web.archive.org/web/20050315004609/http://en.chinabroadcast.cn/2246/2005-2-14/90%40206385.htm|archive-date=15 March 2005|url-status=dead|df=dmy-all}}</ref>\n\nThe name "Chroma-Key" was [[RCA]]'s trade name for the process, as used on its [[NBC]] television broadcasts, incorporating patents granted to RCA's Albert N. Goldsmith.<ref>"Studio: The World--NBC Introduces 'Chroma-Key' to Extend Scope of TV Settings." Electronic Age, January 1958, 8.</ref> A very early broadcast use was NBC's George Gobel Show in fall 1957.<ref>Johnson, Erskine. "Video's Special Effects Men Becoming Master Magicians of Hollywood; Many Tricks." (NEA syndicated article) Gloversville (NY) Leader-Herald, 6 December 1957.</ref>\n\n[[Petro Vlahos]] was awarded an Academy Award for his refinement of these techniques in 1964. His technique exploits the fact that most objects in real-world scenes have a colour whose blue-colour component is similar in intensity to their green-colour component. [[Zbigniew Rybczy\u0144ski]] also contributed to bluescreen technology. An [[optical printer]] with two projectors, a film camera and a "beam splitter", was used to combine the actor in front of a blue screen together with the background footage, one frame at a time. In the early 1970s, American and British television networks began using green backdrops instead of blue for their newscasts. During the 1980s, [[minicomputer]]s were used to control the optical printer. For the film ''[[The Empire Strikes Back]]'', [[Richard Edlund]] created a "quad optical printer" that accelerated the process considerably and saved money. He received a special [[Academy Awards|Academy Award]] for his innovation.\n\nFor decades, travelling matte shots had to be done "locked-down", so that neither the matted subject nor the background could shift their camera perspective at all. Later, computer-timed, [[Motion control photography|motion-control]] cameras alleviated this problem, as both the foreground and background could be filmed with the same camera moves.\n\nMeteorologists on television often use a field monitor, to the side of the screen, to see where they are putting their hands against the background images. A newer technique is to project a faint image onto the screen.\n\nSome films make heavy use of chroma key to add backgrounds that are constructed entirely using [[computer-generated imagery]] (CGI). Performances from different takes can be composited together, which allows actors to be filmed separately and then placed together in the same scene. Chroma key allows performers to appear to be in any location without leaving the studio.\n\nAdvances in computer technology have simplified the [[camera tracking|incorporation of motion]] into composited shots, even when using handheld cameras. Reference points such as a painted grid, X's marked with tape, or equally spaced tennis balls attached to the wall, can be placed onto the coloured background to serve as markers. In post-production, a computer can use these markers to compute the camera's position and thus render an image that matches the perspective and movement of the foreground perfectly. Modern advances in software and computational power have eliminated the need to accurately place the markers\u200a\u2060\u2014\u200a\u2060the software figures out their position in space; a potential disadvantage of this is that it requires camera movement, possibly contributing to modern [[Cinematography|cinematographic]] techniques whereby the camera is always in motion."}},
{"article_title": "Disruptive innovation", "pageid": "47886", "revid": "1062678723", "timestamp": "2021-12-29T22:04:53Z", "history_paths": [["Disruptive innovation --- Introduction ---", "History and usage of the term"]], "categories": ["innovation", "product management", "technology by type"], "heading_tree": {"Disruptive innovation --- Introduction ---": {"History and usage of the term": {"What is (isn't) disruptive innovation": {}}, "Theory": {}, "Disruptive technology": {}, "High-technology effects": {}, "Internal auditor response": {}, "A proactive approach to disruptive innovation": {}, "Example of disruption": {}, "Examples": {}, "Potential opportunities": {}, "Potential threats": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Disruptive innovation --- Introduction ---|History and usage of the term": "The term '''disruptive technologies''' was coined by Clayton M. Christensen and introduced in his 1995 article ''Disruptive Technologies: Catching the Wave'',<ref>Bower, Joseph L. & Christensen, Clayton M. (1995). However the concept of new technologies leading to wholesale economic change is not a new idea since [[Joseph Schumpeter]] adapted the idea of creative destruction from [[Karl Marx]]. Schumpeter (1949) in one of his examples used "the railroadization of the Middle West as it was initiated by the Illinois Central". He wrote, "The Illinois Central not only meant very good business whilst it was built and whilst new cities were built around it and land was cultivated, but it spelled the death sentence for the [old] agriculture of the West."Disruptive Technologies: Catching the Wave" ''[[Harvard Business Review]]'', January\u2013February 1995</ref> which he cowrote with Joseph Bower. The article is aimed at both management executives who make the funding or purchasing decisions in companies, as well as the research community, which is largely responsible for introducing the disruptive vector to the consumer market. He describes the term further in his book ''[[The Innovator's Dilemma]]''.<ref name="Christensen1997">{{Harvnb|Christensen|1997}}.</ref> ''Innovator's Dilemma'' explored the case of the disk drive industry (the disk drive and memory industry, with its rapid technological evolution, is to the study of technology what fruit flies are to the study of genetics, as Christensen was told in the 1990s<ref name="Christensen1997p3">{{Harvnb|Christensen|1997|p=3}}.</ref>) and the excavating and Earth-moving industry (where [[hydraulic machinery|hydraulic actuation]] slowly, yet eventually,  displaced cable-actuated machinery). In his sequel with Michael E. Raynor, ''The Innovator's Solution'',<ref name="Christensen2003">{{Harvnb|Christensen|2003}}.</ref> Christensen replaced the term ''disruptive technology'' with ''disruptive innovation'' because he recognized that most technologies are not intrinsically disruptive or sustaining in character; rather, it is the ''business model'' that identifies the crucial idea that potentiates profound market success and subsequently serves as the disruptive vector. However, comprehending Christensen's business model, which takes the disruptive vector from the idea borne from the mind of the innovator to a marketable product, is central to understanding how novel technology facilitates the rapid destruction of established technologies and markets by the disruptor. Christensen and Mark W. Johnson, who cofounded the management consulting firm [[Innosight]], described the dynamics of "business model innovation" in the 2008 ''[[Harvard Business Review]]'' article "Reinventing Your Business Model".<ref>Johnson, Mark, Christensen, Clayton, et al., 2008, "Reinventing Your Business Model, ''Harvard Business Review'', December 2008.</ref> The concept of disruptive technology continues a long tradition of identifying radical technological  change in the study of [[innovation]] by economists, and its implementation and execution   by its management at a corporate or policy level.\n\nAccording to Christensen, "the term 'disruptive innovation' is misleading when it is used to refer to the derivative, or 'instantaneous value', of the market behavior of the product or service, rather than the integral, or 'sum over histories', of the product's market behavior."<ref name=":0" />\n\nIn the late 1990s, the automotive sector began to embrace a perspective of "constructive disruptive technology" by working with the consultant David E. O'Ryan, whereby the use of current off-the-shelf technology was integrated with newer innovation to create what he called "an unfair advantage". The process or technology change as a whole had to be "constructive" in improving the current method of manufacturing, yet disruptively impact the whole of the business case model, resulting in a significant reduction of waste, energy, materials, labor, or legacy costs to the user.\n\nIn keeping with the insight that a persuasive advertising campaign can be just as effective as technological sophistication at bringing a successful product to market, Christensen's theory explains why many disruptive innovations are ''not'' advanced or useful technologies, which a default hypothesis would lead one to expect. Rather, they are often combinations of existing off-the-shelf components, applied shrewdly to a small, fledgling value network.\n\nOnline news site [[TechRepublic]] proposes an end using the term, and similar related terms, suggesting that, as of 2014, it is overused jargon.<ref>Conner Forrest, May 1, 2014, 5:52 AM PST, https://www.techrepublic.com/article/startup-jargon-10-terms-to-stop-using/</ref>\n\n \n* Disruption is a process, not a product or service, that occurs from the nascent to the mainstream \n* Originate in low-end (less demanding customers) or new market (where none existed) footholds\n* New firms don't catch on with mainstream customers until quality catches up with their standards\n* Success is not a requirement and some business can be disruptive but fail\n* New firm's business model differs significantly from incumbent<ref name=":0">{{Cite news|url=https://hbr.org/2015/12/what-is-disruptive-innovation|title=What Is Disruptive Innovation?|last1=Christensen|first1=Clayton M.|date=2015-12-01|work=Harvard Business Review|access-date=2019-06-25|last2=Raynor|first2=Michael E.|issue=December 2015|issn=0017-8012|last3=McDonald|first3=Rory}}</ref>\n\nChristensen continues to develop and refine the theory and has accepted that not all examples of disruptive innovation perfectly fit into his theory. For example, he conceded that originating in the low end of the market is not always a cause of disruptive innovation, but rather it fosters competitive business models, using [[Uber]] as an example. In an interview with [[Forbes]] magazine he stated:<blockquote>"Uber helped me realize that it isn\u2019t that being at the bottom of the market is the causal mechanism, but that it\u2019s correlated with a business model that is unattractive to its competitor".<ref>{{Cite web|url=https://www.forbes.com/sites/forbestreptalks/2016/10/03/clayton-christensen-on-what-he-got-wrong-about-disruptive-innovation/|title=Clayton Christensen On What He Got Wrong About Disruptive Innovation|last=Adams|first=Susan|website=Forbes|language=en|access-date=2019-10-16}}</ref></blockquote>"}},
{"article_title": "Vacuum cleaner", "pageid": "49105", "revid": "1062550812", "timestamp": "2021-12-29T04:07:25Z", "history_paths": [["Vacuum cleaner --- Introduction ---", "History"]], "categories": ["vacuum cleaners", "1860 introductions", "american inventions", "cleaning tools", "english inventions", "floors", "gas technologies", "home appliances", "home automation", "19th-century inventions"], "heading_tree": {"Vacuum cleaner --- Introduction ---": {"Name": {}, "History": {"Manual vacuums": {}, "Powered vacuum cleaners": {}, "Domestic vacuum cleaner": {}, "Post-Second World War": {}, "Recent developments": {}}, "Modern configurations": {"Upright": {}, "Canister": {}, "Drum": {}, "Wet/dry": {}, "Pneumatic": {}, "Backpack": {}, "Hand-held": {}, "Robotic": {}, "Cyclonic": {}, "Central": {"Constellation": {}}, "Vehicles": {}, "Other": {}}, "Technology": {"Exhaust filtration": {}, "Attachments": {}, "Specifications": {"Suction": {}, "Input power": {}, "Output power": {}, "Peak horsepower": {}}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Vacuum cleaner --- Introduction ---|History": "[[File:VacuumCleanerIXLMuseum.jpg|upright|left|thumb|An early hand-pumped vacuum cleaner]]\nThe vacuum cleaner evolved from the [[carpet sweeper]] via [[manual vacuum cleaners]]. The first manual models, using bellows, were developed in the 1860s, and the first motorized designs appeared at the turn of the 20th century, with the first decade being the boom decade.\n\n {{Main|Manual vacuum cleaner}}\n[[File:Hess carpet sweeper patent model.png|right|thumb|Patent model of Daniel Hess's carpet sweeper]]\nIn 1860 a manual vacuum cleaner was invented by Daniel Hess of [[West Union, Iowa]]. Called a 'carpet sweeper', It gathered dust with a rotating brush and had a bellows for generating suction.<ref>{{cite web|title=Fascinating facts about the invention of vacuum cleaner by Daniel Hess in 1860|publisher=The Great Idea Finder|url=http://www.ideafinder.com/history/inventions/vacleaner.htm|archive-url=https://web.archive.org/web/20190710060520/http://www.ideafinder.com/history/inventions/vacleaner.htm|url-status=dead|archive-date=2019-07-10}}</ref><ref>Hess, Daniel (10 July 1860) "Carpet-Sweeper" {{US Patent|29077}}</ref>\nAnother early model (1869) was the "Whirlwind", invented in [[Chicago]] in 1868 by [[Ives W. McGaffey]]. The bulky device worked with a belt driven fan cranked by hand that made it awkward to operate, although it was commercially marketed with mixed success.\n<ref>McGaffey, Ives W. (8 June 1869) "Improved-Sweeping Machine" {{US Patent|91145}}</ref>\nA similar model was constructed by [[Melville R. Bissell]] of [[Grand Rapids, Michigan]] in 1876, who also manufactured [[carpet sweeper]]s.<ref name="bissellsite">{{cite web|url=http://www.bissell.com/Our-History/|title=Our History |publisher=Bissell|access-date=5 April 2010}}</ref> The company later added portable vacuum cleaners to its line of cleaning tools.\n\n {{See|Hubert Cecil Booth#Vacuum cleaner|David T. Kenney}}\n[[File:Vacuum Cleaner 1906.jpg|upright|thumb|[[Maid|Housemaid]] using "dedusting pump", circa 1906.]]\n\nThe end of the 19th century saw the introduction of powered cleaners, although early types used some variation of blowing air to clean instead of suction.<ref name="Gantz, Carroll 2012 p. 45">Gantz, Carroll (21 Sep 2012). The Vacuum Cleaner: A History. McFarland. p. 45</ref> One appeared in 1898 when John S. Thurman of [[St. Louis]], [[Missouri]] submitted a patent (U.S. No. 634,042) for a "pneumatic carpet renovator" which blew dust into a receptacle.<ref name="americanheritage">{{cite web|url=http://www.americanheritage.com/articles/magazine/it/2006/4/2006_4_4.shtml|title=The Vacuum Cleaner|author=Wohleber, Curt|date=Spring 2006|access-date=8 December 2010|work=Invention & Technology Magazine|publisher=American Heritage Publishing|url-status=dead|archive-url=https://web.archive.org/web/20100313170420/http://www.americanheritage.com/articles/magazine/it/2006/4/2006_4_4.shtml|archive-date=13 March 2010}}</ref> Thurman's system, powered by an [[internal combustion engine]], traveled to the customers residence on a horse-drawn wagon as part of a door to door cleaning service. Corrine Dufour of [[Savannah, Georgia]] received two patents in 1899 and 1900 for another blown air system that seems to have featured the first use of an electric motor.<ref name="Gantz, Carroll 2012 p. 45"/>\n\nIn 1901 powered vacuum cleaners using suction were invented independently by British engineer [[Hubert Cecil Booth]] and American inventor [[David T. Kenney]].<ref name="Gantz, Carroll 2012 p. 49">Gantz, Carroll (21 Sep 2012). The Vacuum Cleaner: A History. McFarland. p. 49</ref><ref name="americanheritage"/> Booth also may have coined the word "vacuum cleaner".<ref name="Gantz, Carroll 2012 p. 49"/> Booth's horse drawn combustion engine powered "Puffing Billy",<ref name="bbc_booth">{{cite news|url=http://news.bbc.co.uk/1/hi/uk/1515776.stm|title=Sucking up to the vacuum cleaner|date=30 August 2001|work=BBC News|access-date=6 December 2010}}</ref> maybe derived from Thurman's blown air design,"<ref name="BVC">{{Cite web|url=http://www.bvc.co.uk/history.html|title=THE STORY OF THE VACUUM CLEANER|work=bvc.co.uk}}</ref> relied upon just suction with air pumped through a cloth filter and was offered as part of his cleaning services. Kenney's was a stationary 4,000 lb. steam engine powered system with pipes and hoses reaching into all parts of the building.\n\n [[File:Vacuum cleaner 1910.JPG|thumb|upright|A hand-powered pneumatic vacuum cleaner, circa 1910. An early electric-powered model is also shown]]\nThe first vacuum-cleaning device to be portable and marketed at the domestic market was built in 1905 by Walter Griffiths, a manufacturer in [[Birmingham]], [[England]].<ref>{{cite web|url=http://www.thepeoplehistory.com/vacuum.html|title=The Changes to Vacuum Cleaners over the last 100 years|work=The People History }}</ref> His ''Griffith's Improved Vacuum Apparatus for Removing Dust from Carpets'' resembled modern-day cleaners; \u2013 it was portable, easy to store, and powered by "any one person (such as the ordinary [[domestic servant]])", who would have the task of compressing a bellows-like contraption to suck up dust through a removable, flexible pipe, to which a variety of shaped nozzles could be attached.\n\n[[File:NMAH DC - IMG 8859.JPG|thumb|left|upright|Early electric vacuum cleaner by Electric Suction Sweeper Company, circa 1908]]\nIn 1906 [[Jim Kirby|James B. Kirby]] developed his first of many vacuums called the "Domestic Cyclone". It used water for dirt separation. Later revisions came to be known as the [[Kirby Company|Kirby]] Vacuum Cleaner. In 1907 department store janitor [[James M. Spangler|James Murray Spangler]] (1848\u20131915) of [[Canton, Ohio]] invented the first portable electric vacuum cleaner,<ref name="VacuumCleaner">{{cite book|last=Levy|first=Joel|title=Really useful: the origins of everyday things|publisher=Firefly Books|url=https://archive.org/details/reallyusefulorig00levy|url-access=registration|isbn=155297622X|year=2003|page=[https://archive.org/details/reallyusefulorig00levy/page/147 147]}}</ref> obtaining a patent for the Electric Suction Sweeper on 2 June 1908. Crucially, in addition to suction from an electric fan that blew the dirt and dust into a soap box and one of his wife's pillow cases, Spangler's design utilized a rotating brush to loosen debris.<ref>{{US patent|889823}}</ref> Unable to produce the design himself due to lack of funding, he sold the patent in 1908 to local leather goods manufacturer [[William Henry Hoover]] (1849\u20131932), who had Spangler's machine redesigned with a steel casing, casters, and attachments, founding the company that in 1922 was renamed the [[Hoover Company]]. Their first vacuum was the 1908 Model O, which sold for $60. Subsequent innovations included the beater bar in 1919 ("It beats as it sweeps as it cleans"),<ref>{{US patent|1364554}}</ref> disposal filter bags in the 1920s, and an upright vacuum cleaner in 1926.\n\nIn [[Continental Europe]], the [[Nilfisk-Advance|Fisker and Nielsen company]] in [[Denmark]] was the first to sell vacuum cleaners in 1910. The design weighed just {{cvt|17.5|kg}} and could be operated by a single person. The Swedish company [[Electrolux]] launched their Model V in 1921 with the innovation of being able to lie on the floor on two thin metal runners.<ref>{{cite news | title = Vacuum cleaner lasts for 70 years | work = BBC News | date = 27 January 2008 | url = http://news.bbc.co.uk/1/hi/england/kent/7205825.stm | access-date = 28 January 2008 }}</ref> In the 1930s the Germany company [[Vorwerk (company)|Vorwerk]] started marketing vacuum cleaners of their own design which they sold through [[direct sales]].\n\n {{Unreferenced section|date=March 2013}}\n[[File:Kirby G5 upright vacuum cleaner - 20140913.jpg|thumb|upright|A [[Kirby Company|Kirby]] G5 vacuum cleaner]]\nFor many years after their introduction, vacuum cleaners remained a luxury item, but after the Second World War, they became common among the [[middle class]]es. Vacuums tend to be more common in Western countries because in most other parts of the world, [[Fitted carpet|wall-to-wall carpeting]] is uncommon and homes have [[tile]] or [[hardwood floor]]s, which are easily swept, wiped or mopped manually without power assist.\n\nThe last decades of the 20th century saw the more widespread use of technologies developed earlier, including filterless cyclonic dirt separation, central vacuum systems and rechargeable hand-held vacuums. In addition, miniaturized computer technology and improved batteries allowed the development of a new type of machine \u2013 the autonomous robotic vacuum cleaner. In 1997 Electrolux of Sweden demonstrated the [[Electrolux Trilobite]], the first autonomous cordless robotic vacuum cleaner on the BBC-TV program ''Tomorrow's World'', introducing it to the consumer market in 2001.<ref>{{cite news|title=Robot cleaner hits the shops|url=http://news.bbc.co.uk/1/hi/technology/3031219.stm|access-date=12 August 2017|work=BBC News|date=16 May 2003}}</ref>\n\n In 2004 a British company released [[Airider]], a hovering vacuum cleaner that floats on a cushion of air, similar to a [[hovercraft]]. It has claimed to be light-weight and easier to maneuver (compared to using wheels), although it is not the first vacuum cleaner to do this \u2013 the Hoover Constellation predated it by at least 35 years.\n\nA British inventor has developed a new cleaning technology known as Air Recycling Technology, which, instead of using a vacuum, uses an air stream to collect dust from the carpet.<ref>Edginton, B. (2008) [http://www.g0cwt.co.uk/arc/ \u201cThe Air Recycling Cleaner\u201d]. g0cwt.co.uk</ref> This technology was tested by the Market Transformation Programme (MTP) and shown to be more energy-efficient than the vacuum method.<ref>Market Transformation Programme (2006), [http://www.mtprog.com/spm/download/document/id/613 \u201cBNXS30: Vacuum cleaners \u2013 UK market, technologies, energy use, test methods and waste\u201d]. Retrieved 20 August 2009.</ref> Although working prototypes exist, Air Recycling Technology is not currently used in any production cleaner."}},
{"article_title": "Carburetor", "pageid": "49209", "revid": "1062474959", "timestamp": "2021-12-28T17:52:03Z", "history_paths": [["Carburetor --- Introduction ---", "History and development"]], "categories": ["american inventions", "carburettors", "engine fuel system technology", "engine components"], "heading_tree": {"Carburetor --- Introduction ---": {"Etymology": {}, "History and development": {}, "Principles": {}, "Operation": {"Basics": {}, "Off-idle circuit": {}, "Main open-throttle circuit": {}, "Power valve": {}, "Accelerator pump": {}, "Choke": {}, "Other elements": {}}, "Fuel supply": {"Float chamber": {}, "Diaphragm chamber": {}}, "Multiple carburetor barrels": {}, "Carburetor adjustment": {}, "Feedback carburetors": {}, "Catalytic carburetors": {}, "{{anchor|CV|vacuum}}Constant vacuum carburetors": {}, "Vaporizers": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Carburetor --- Introduction ---|History and development": "The first carburetor was invented by [[Samuel Morey]] in 1826. The first person to patent a carburetor for use in a petroleum engine was [[Siegfried Marcus]] with his 6 July 1872 patent for a device that mixes fuel with air.\n\nA carburetor was among the early patents by [[Karl Benz]] (1888)<ref>{{cite web|url= http://www.google.com/patents/US382585 |title=Carbueetoe |website=Google.com |access-date=8 October 2017}}</ref> as he developed internal combustion engines and their components.<ref>{{cite book|url= https://books.google.com/books?id=6Is_rosCeKUC&q=benz+carburetor+inventore&pg=PA91 |page=91 |title=Inventors and Inventions |publisher=Marshall Cavendish |year=2008 |isbn=9780761477617 |access-date=19 January 2014}}</ref>\n\n{{anchor|Surface carburetor}}Early carburetors were of the surface type, in which air is combined with fuel by passing over the surface of gasoline.<ref>{{citation|title=Webster's Revised Unabridged Dictionary|year=1913 |title-link=1913 Webster's}}</ref>\n\nIn 1885, [[Wilhelm Maybach]] and [[Gottlieb Daimler]] developed a float carburetor based on the [[atomizer nozzle]].<ref>{{cite book|title=World History of the Automobile |last=Eckermann |first=Erik |publisher=Society of Automotive Engineers |url= https://books.google.com/books?id=yLZeQwqNmdgC&pg=PA276 |page=276 |year=2001 |isbn=978-0-7680-0800-5}}</ref> The Daimler-Maybach carburetor was copied extensively, leading to patent lawsuits. British courts rejected the Daimler company's claim of priority in favor of [[Edward Butler (inventor)|Edward Butler]]'s 1884 spray carburetor used on his [[Butler Petrol Cycle|Petrol Cycle]].<ref>{{cite web |title=Csonka J\u00e1nos Eml\u00e9km\u00fazeum - The pulverized (spray carburetor) |url= http://www.csonkamuzeum.hu/index.php?option=com_content&view=category&layout=blog&id=63&Itemid=154 |website=csonkamuzeum.hu |access-date=2 November 2020 |language=en |date=2011}}</ref><ref>{{citation |url= https://books.google.com/books?id=pDbQVE3IdTcC&pg=PA335 |page=335 |access-date=July 27, 2014 |title=Scientific American Inventions and Discoveries: All the Milestones in Ingenuity\u2014From the Discovery of Fire to the Invention of the Microwave Oven |first=Rodney |last=Carlisle |publisher=John Wiley & Sons |year=2005 |isbn=9780471660248 }}</ref>\n\nHungarian [[engineer]]s [[J\u00e1nos Csonka]] and [[Don\u00e1t B\u00e1nki]] patented a carburetor for a [[stationary engine]] in 1893.<ref>{{cite book|first1=John S. |last1=Rigden |first2=Roger H. |last2=Stuewer |title=The Physical Tourist: A Science Guide for the Traveler |publisher=Springer |year=2009 |url= https://books.google.com/books?id=i4uLnMZeACsC&pg=PA193 |isbn=978-3-7643-8933-8}}</ref><ref>{{cite web|url= http://www.scitech.mtesz.hu/51landmark/banki.htm |title=Don\u00e1t B\u00e1nki |website=Scitech.mtesz.hu |archive-url= https://web.archive.org/web/20120717091817/http://www.scitech.mtesz.hu/51landmark/banki.htm |archive-date=17 July 2012 |access-date=19 January 2014}}</ref><ref>{{cite web|url= http://www.csonkamuzeum.hu/index.php?option=com_content&view=category&layout=blog&id=63&Itemid=154 |title=Inspirator and Pulverizer}}</ref>\n\n[[Frederick W. Lanchester|Frederick William Lanchester]] of [[Birmingham]], England, experimented with the wick carburetor in cars. In 1896, Frederick and his brother built a gasoline-driven car in England, a single-cylinder {{convert|5|hp|kW|abbr=on}} internal combustion engine with chain drive. Unhappy with the car's performance and power, they re-designed the engine the following year using two horizontally-opposed cylinders and a newly designed wick carburetor.\n\nCarburetors were the common method of fuel delivery for most US-made [[gasoline]] engines until the late 1980s when fuel injection became the preferred method.<ref>{{cite book|url=https://books.google.com/books?id=yLZeQwqNmdgC&pg=PA199 |title=World History of the Automobile |first=Erik |last=Eckermann |pages=199\u2013200 |publisher=Society of Automotive Engineers |year=2001 |access-date=2016-05-09 |isbn=9780768008005 }}</ref> This change was dictated by the requirements of [[catalytic converter]]s and not due to an inherent inefficiency of carburation. A catalytic converter requires that there be more precise control over the fuel/air mixture in order to control the amount of oxygen remaining in the exhaust gases. In the U.S. market, the last cars using carburetors were:\n*1990 (General public) : [[Oldsmobile Custom Cruiser]], [[Buick Estate|Buick Estate Wagon]], [[Cadillac Brougham]], [[Honda Prelude]] (Base Model), [[Subaru Justy]]\n*1991 (Police) : [[Ford Crown Victoria Police Interceptor]] with the {{convert|351|cuin|L|1|abbr=on|order=flip}} V8 engine.<ref>{{cite web |title=1991 Ford LTD Crown Victoria Police Interceptor "P72" 351 Windsor all original! for sale |url= http://topclassiccarsforsale.com/ford/597005-1991-ford-ltd-crown-victoria-police-interceptor-p72-351-windsor-all-original.html |website=topclassiccarsforsale.com |access-date=February 27, 2021}}</ref>\n*1991 (SUV) : [[Jeep Wagoneer|Jeep Grand Wagoneer]] with the [[AMC V8 engine|AMC]] {{convert|360|cuin|L|1|abbr=on}} V8 engine.<ref>{{cite book|url= https://books.google.com/books?id=eT7LT69STO0C&pg=PA228|page=228|title=Ultimate American V-8 Engine Data Book |edition=Second |first=Peter C. |last=Sessler |publisher=MBI |year=2010 |isbn=9780760336816}}</ref>\n*1993 (Light Truck) : Mazda B2200\n*1994 (Light truck) : [[Isuzu]]<ref>{{cite web |last1=Fink |first1=Greg |title=Automotive Lasts: The Last Cars With Cassette Decks, Carbs, Bench Seats, and More (slide 4) |url= https://www.motortrend.com/features-collections/last-cars-cassette-decks-carbs-bench-seats/?slide=4 |publisher=Motor Trend |access-date=February 27, 2021 |date=May 30, 2020}}</ref><ref>{{cite web|url= http://www.rockauto.com/catalog/raframecatalog.php |title=Rockauto online auto parts catalogue |publisher=Rockauto.com |date=2010-12-17 |access-date=2011-01-01}}</ref>\n*1995 (Light Truck) : [[Toyota Pickup]] with the 22r 2.4 L inline 4.\nIn Australia, some cars continued to use carburetors well into the 1990s; these included the Honda Civic (1993), the Ford Laser (1994), the Mazda 323 and Mitsubishi Magna sedans (1996), the Daihatsu Charade (1997), and the Suzuki Swift (1999). Low-cost commercial vans and 4WDs in Australia continued with carburetors even into the 2000s, the last being the Mitsubishi Express van in 2003.{{Citation needed|date=September 2011}} Elsewhere, certain [[Lada]] cars used carburetors until 2006. Many motorcycles still use carburetors for simplicity's sake, since a carburetor does not require an electrical system to function. Carburetors are also still found in small engines and in older or specialized [[automobile]]s, such as those designed for [[stock car racing]], though [[NASCAR]]'s 2011 Sprint Cup season was the last one with carbureted engines; electronic fuel injection was used beginning with the 2012 race season in Cup.<ref>{{cite web|first=Mark |last=Aumann |url= http://www.nascar.com/news/111018/inside-nascar-fuel-injection-replaces-carburetor/index.html |title=NASCAR takes 'really big step' with fuel injection |website=Nascar.com |date=11 January 2012 |archive-url= https://web.archive.org/web/20121025133612/http://www.nascar.com/news/111018/inside-nascar-fuel-injection-replaces-carburetor/index.html |archive-date=25 October 2012 |access-date=19 January 2014}}</ref>\n\nIn Europe, carburetor-engined cars were being gradually phased out by the end of the 1980s in favor of fuel injection, which was already the established type of engine on more expensive vehicles including luxury and sports models. [[European Economic Community|EEC]] legislation required all vehicles sold and produced in member countries to have a catalytic converter after December 1992. This legislation had been in the pipeline for some time, with many cars becoming available with catalytic converters or fuel injection from around 1990. However, some versions of the [[Peugeot 106]] were sold with carburetor engines from its launch in 1991, as were versions of the [[Renault Clio]] and [[Nissan Primera]] (launched in 1990) and initially all versions of [[Ford Fiesta]] range except the XR2i when it was launched in 1989. Luxury car manufacturer Mercedes-Benz had been producing mechanically fuel-injected cars since the early 1950s, while the first mainstream family car to feature fuel injection was the [[Volkswagen Golf]] GTI in 1976. [[Ford Motor Company|Ford's]] first fuel-injected car was the [[Ford Capri]] RS 2600 in 1970. [[General Motors]] launched its first fuel-injected car in 1957 as an option available for the first generation [[Chevrolet Corvette (C1)|Corvette]]. [[Saab Automobile|Saab]] switched to fuel injection across its whole range from 1982, but kept carbureted engines as an option on certain models until 1989."}},
{"article_title": "JFS (file system)", "pageid": "50487", "revid": "1031719786", "timestamp": "2021-07-03T07:13:09Z", "history_paths": [["JFS (file system) --- Introduction ---", "History"]], "categories": ["1990 software", "compression file systems", "disk file systems", "file systems supported by the linux kernel", "ibm file systems", "os/2 technology"], "heading_tree": {"JFS (file system) --- Introduction ---": {"History": {}, "Features": {"Journal": {}, "B+ tree": {}, "Dynamic inode allocation": {}, "Extents": {}, "Compression": {}, "Concurrent input / output (CIO)": {}, "Allocation groups": {}, "Superblocks": {}}, "On Linux": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"JFS (file system) --- Introduction ---|History": "IBM introduced JFS with the initial release of AIX version 3.1 in February 1990. This file system, now called ''JFS1 on AIX'', was the premier file system for AIX over the following decade and was installed in thousands or millions of customers' AIX systems. Historically, the JFS1 file system is very closely tied to the memory manager of AIX,<ref name="faq" /> which is a typical design for a file system supporting only one operating system. JFS was one of the first file systems to support [[Journaling file system|Journaling]]\n\nIn 1995, work began to enhance the file system to be more scalable and to support machines that had more than one processor. Another goal was to have a more portable file system, capable of running on multiple operating systems. After several years of designing, coding, and testing, the new JFS was first shipped in OS/2 Warp Server for eBusiness in April 1999, and then in OS/2 Warp Client in October 2000. In December 1999, a snapshot of the original OS/2 JFS source was granted to the [[Open-source model|open source]] community and work was begun to port JFS to [[Linux]]. The first stable release of ''JFS for Linux'' appeared in June 2001.<ref name="interview" /> The ''JFS for Linux'' project is maintained by a small group of contributors known as the ''JFS Core Team''.<ref name="JFS4Linux">{{cite web |url=http://jfs.sourceforge.net/ |title=JFS for Linux |website=JFS.SourceForge.net |access-date=August 26, 2020}}</ref> This release of sources also worked to form the basis of a re-port back to OS/2 of the open-source JFS.\n\nIn parallel with this effort, some of the JFS development team returned to the AIX Operating System Development Group in 1997 and started to move this new JFS source base to the AIX operating system.  In May 2001, a second journaled file system, ''Enhanced Journaled File System (JFS2)'', was made available for AIX 5L.<ref name="faq" /><ref name="interview" />\n\nEarly in 2008 there was speculation that IBM is no longer interested in maintaining JFS and thus it should not be used in production environments.<ref>{{Cite web |url=http://linux.derkeiler.com/Mailing-Lists/Debian/2008-01/msg01808.html |title=Re: which to use: ext3, JFS, XFS, ReiserFS?<!-- Bot generated title --> |access-date=March 31, 2008 |archive-url=https://web.archive.org/web/20160303200517/http://linux.derkeiler.com/Mailing-Lists/Debian/2008-01/msg01808.html |archive-date=March 3, 2016 |url-status=dead }}</ref> However, Dave Kleikamp, a member of the [[IBM Linux Technology Center]] and JFS Core Team,<ref name="JFS4Linux" /> explained that they still follow changes in the [[Linux kernel]] and try to fix potential [[software bugs]]. He went on to add that certain distributions expect a larger resource commitment from them and opt not to support the filesystem.<ref>[http://sourceforge.net/mailarchive/forum.php?thread_name=fpps5p%24g2t%242%40saturn.local.net&forum_name=jfs-discussion SourceForge.net: jfs-discussion<!-- Bot generated title -->]</ref>\n\nIn 2012, [[Trim (computing)|TRIM]] command support for [[solid-state drive]]s was added to JFS.<ref>{{cite web|title=TRIM support for JFS Filesystem|url=https://lkml.org/lkml/2012/7/26/691}}</ref>"}},
{"article_title": "Funicular", "pageid": "50680", "revid": "1058765351", "timestamp": "2021-12-05T13:59:58Z", "history_paths": [["Funicular --- Introduction ---", "History"]], "categories": ["funicular railways", "rail technologies", "railways by type", "vertical transport devices"], "heading_tree": {"Funicular --- Introduction ---": {"Operation": {"Types of power systems": {"Electric motor": {}, "Water counterbalancing": {}}, "Track layout": {"Turnout systems for two-rail funiculars": {}}, "Stations": {}}, "History": {}, "Exceptional examples": {}, "Comparison with inclined elevators": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Funicular --- Introduction ---|History": "[[File:T\u00fcnel Istanbul.jpg|thumb|T\u00fcnel in Istanbul, launched in 1875, Karak\u00f6y station as of 2006]]\n\nA number of [[cable railway]] systems which pull their cars on inclined slopes were built since the 1820s. \nIn the second half of the 19th century the design of a funicular as a transit system emerged. \nIt was especially attractive in comparison with the other systems of the time as counterbalancing of the cars was deemed to be a cost-cutting solution.<ref name="Giessbach" />\n\nThe first line of the [[Funiculars of Lyon]] ({{lang|fr|Funiculaires de Lyon}}) opened in 1862, followed by other lines in 1878, 1891 and 1900. The [[Budapest Castle Hill Funicular]] was built in 1868\u201369, with the first test run on 23 October 1869. \nThe oldest funicular railway operating in Britain dates from 1875 and is in [[Scarborough, North Yorkshire|Scarborough]], North Yorkshire.<ref>{{cite news| url=http://news.bbc.co.uk/1/hi/england/north_yorkshire/8017535.stm |work=BBC News | title=Blunder traps eight on cliff lift | date=24 April 2009 | access-date=2 April 2010}}</ref>\nIn [[Istanbul]], Turkey, the [[T\u00fcnel]] has been in continuous operation since 1875 and is both the first underground funicular and the second-oldest underground railway. \nIt remained powered by a steam engine up until it was taken for renovation in 1968.<ref>{{cite web |url=http://tunel.iett.istanbul/tr/tunel/pages/tunel-kronolojisi/566 |title=T\u00fcnel Kronolojisi |trans-title=T\u00fcnel Chronology  |publisher=\u0130ETT - Tunnel |language=tr |access-date=2017-12-07 }}</ref>\n\nUntil the end of the 1870s, the four-rail parallel-track funicular was the normal configuration. [[Carl Roman Abt]] developed the Abt Switch allowing the two-rail layout, which was used for the first time in 1879 when the [[Giessbach Funicular]] opened in [[Switzerland]].<ref name="hefti" />\n\nIn the United States, the first funicular to use a two-rail layout was the [[Telegraph Hill Railroad]] in San Francisco, which was in operation from 1884 until 1886.<ref>{{cite web|title=Telegraph Hill Railroad|url=http://www.cable-car-guy.com/html/ccsf.html#thrr|date=1 July 2009|work=The Cable Car Home Page \u2013 Cable Car Lines in San Francisco|publisher=Joe Thompson|access-date=20 September 2009|quote=The Telegraph Hill Railroad was not a cable car line ...; it was a funicular railway}}</ref> The [[Mount Lowe Railway]] in Altadena, California, was the first [[mountain railway]] in the United States to use the three-rail layout. Three- and two-rail layouts considerably reduced the space required for building a funicular, reducing grading costs on mountain slopes and property costs for urban funiculars. These layouts enabled a funicular boom in the latter half of the 19th century.\n\nCurrently, the United State\u2019s oldest and steepest funicular in continuous use is the [[Monongahela Incline]] located in [[Pittsburgh, Pennsylvania]] Construction began in 1869 and officially opened May 28th 1870 for passenger use. The Monongahela incline also has the distinction of being the first funicular in the United States for strictly passenger use and not freight.<ref>{{cite web |url=https://inclinedplane.tripod.com/otherpaincl.htm |title=Duquesne Incline, Pittsburgh, Pennsylvania: Other Pennsylvania Inclines |website=inclinedplane.tripod.com/ }} </ref>\n\nIn 1880 the funicular of [[Mount Vesuvius]] inspired the Italian popular song ''[[Funicul\u00ec, Funicul\u00e0]]''. This funicular was destroyed repeatedly by volcanic eruptions and abandoned after the eruption of 1944.<ref>{{cite journal |last1=Smith |first1=Paul |title=Thomas Cook & Son's Vesuvius Railway |journal=Japan Railway & Transport Review |date=March 1998 |url=http://www.ejrcf.or.jp/jrtr/jrtr15/pdf/f10_smi.pdf}}</ref>"}},
{"article_title": "Pipeline transport", "pageid": "51111", "revid": "1062322314", "timestamp": "2021-12-27T19:29:03Z", "history_paths": [["Pipeline transport --- Introduction ---", "Oil and natural gas"], ["Pipeline transport --- Introduction ---", "Water"]], "categories": ["pipeline transport", "freight transport", "piping", "gas technologies", "infrastructure"], "heading_tree": {"Pipeline transport --- Introduction ---": {"Oil and natural gas": {"Growth of market": {}, "Construction and operation": {}}, "Ammonia": {}, "Alcohol fuels": {}, "Coal and ore": {}, "Hydrogen": {}, "Water": {}, "Other systems": {"District heating": {}, "Beer": {}, "Brine": {}, "Milk": {}}, "Marine pipelines": {}, "Functions": {}, "Development and planning": {}, "Operation": {}, "Technology": {"Components": {}, "Leak detection systems": {}}, "Implementation": {}, "Maintenance": {}, "Regulation": {}, "Pipelines and geopolitics": {}, "Hazard identification": {}, "Exposure": {"Spill frequency-volume": {}, "Benzene fate and transport": {}, "Previous dilbit spill remediation difficulties": {}}, "Accidents and dangers": {"Accidents": {}, "As targets": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Pipeline transport --- Introduction ---|Oil and natural gas": "<!-- This heading is linked by many redirects. Do not change without updating the associated links. -->\n{{See also|List of oil pipelines|List of natural gas pipelines}}\n\n{{Split section|Oil pipeline|Gas pipeline|date=June 2019|discuss=Talk:Pipeline_transport#Giving_the_oil_and_gas_pipeline_their_own_articles}}\n\n[[File:Pipeline device.jpg|thumb|left|A "[[Pipeline inspection gauge|Pig]]" launcher/receiver, on the natural gas pipeline in Switzerland]]\n\nIt is uncertain when the first [[crude oil]] pipeline was built.<ref>{{cite news|last1=Waldman|first1=Jonathan|title=How the Oil Pipeline Began|url=http://nautil.us/issue/50/emergence/how-the-oil-pipeline-began|access-date=6 July 2017|work=[[Nautilus (science magazine)]]|date=6 July 2017}}</ref> Credit for the development of pipeline transport is disputed,{{Citation needed|date=February 2018}} with competing claims for [[Vladimir Shukhov]] and the [[Branobel]] company in the late 19th century, and the Oil Transport Association, which first constructed a {{convert|2|in|mm|adj=on}} wrought iron pipeline over a {{convert|6|mi|km|adj=on}} track from an oil field in Pennsylvania to a railroad station in [[Oil Creek State Park#History|Oil Creek]], in the 1860s. Pipelines are generally the most economical way to transport large quantities of oil, [[refined oil products]] or [[natural gas]] over land. For example, in 2014, pipeline transport of crude oil cost about $5 per barrel, while rail transport cost about $10 to $15 per barrel.<ref name="forbes">{{cite magazine |url=https://www.forbes.com/sites/jamesconca/2014/04/26/pick-your-poison-for-crude-pipeline-rail-truck-or-boat/ |title=Pick Your Poison For Crude -- Pipeline, Rail, Truck Or Boat |author=James Conca |date=26 April 2014 |magazine=Forbes}}</ref> Trucking has even higher costs due to the additional labor required; employment on completed pipelines represents only "1% of that of the trucking industry.".<ref>{{cite web|url=http://cepac.cheme.cmu.edu/pasi2008/slides/cerda/library/slides/jcerda-pasi-2008-1page.pdf |title=Oil Pipeline Logistics |publisher=Cepac.cheme.cmu.edu |access-date=2015-05-04}}</ref>\n\nIn the United States, 70% of crude oil and petroleum products are shipped by pipeline. (23% are by ship, 4% by truck, and 3% by rail)  In Canada for natural gas and petroleum products, 97% are shipped by pipeline.<ref name="forbes" />\n\nNatural gas (and similar gaseous fuels) are lightly pressurized into liquids known as Natural Gas Liquids (NGLs). Small NGL processing facilities can be located in oil fields so the butane and propane liquid under light pressure of {{convert|125|psi|kPa}}, can be shipped by rail, truck or pipeline. Propane can be used as a fuel in oil fields to heat various facilities used by the oil drillers or equipment and trucks used in the oil patch. EG: Propane will convert from a gas to a liquid under light pressure, 100 psi, give or take depending on temperature, and is pumped into cars and trucks at less than {{convert|125|psi|kPa|abbr=on}} at retail stations. Pipelines and rail cars use about double that pressure to pump at {{convert|250|psi|kPa|abbr=on}}.[[File:Pipeline-small image, seen from below.jpeg|thumb|200px|An elevated section of the [[Trans-Alaska Pipeline System|Alaska Pipeline]].]]The distance to ship propane to markets is much shorter, as thousands of [[natural-gas processing]] plants are located in or near oil fields. Many [[Bakken Formation|Bakken]] Basin oil companies in North Dakota, Montana, Manitoba and Saskatchewan gas fields separate the NGLs in the field, allowing the drillers to sell propane directly to small wholesalers, eliminating the large refinery control of product and prices for propane or butane.\n\nThe most recent major pipeline to start operating in North America, is a TransCanada natural gas line going north across the Niagara region bridges with Marcellus shale gas from Pennsylvania and others tied in methane or natural gas sources, into the Canadian province of Ontario as of the fall of 2012, supplying 16 percent of all the natural gas used in Ontario.\n\n[[File:Major russian gas pipelines to europe.png|thumb|right|upright=1.4|Major Russian gas pipelines to Europe in 2009]]\nThis new US-supplied natural gas displaces the natural gas formerly shipped to Ontario from western Canada in Alberta and Manitoba, thus dropping the government regulated pipeline shipping charges because of the significantly shorter distance from gas source to consumer.  To avoid delays and US government regulation, many small, medium and large oil producers in North Dakota have decided to run an oil pipeline north to Canada to meet up with a Canadian oil pipeline shipping oil from west to east. This allows the Bakken Basin and Three Forks oil producers to get higher negotiated prices for their oil because they will not be restricted to just one wholesale market in the US. The distance from the biggest oil patch in North Dakota, in [[Williston, North Dakota]], is only about 85 miles or 137 kilometers to the Canada\u2013US border and [[Manitoba]]. [[Mutual fund]]s and [[joint venture]]s are big investors in new oil and gas pipelines. In the fall of 2012, the US began exporting [[propane]] to Europe, known as LPG, as wholesale prices there are much higher than in North America. Additionally, a pipeline is currently being constructed from North Dakota to Illinois, commonly known as the [[Dakota Access Pipeline]].<ref>{{Cite web|title=About {{!}} Dakota Access Pipeline|url=https://daplpipelinefacts.com/About.html|access-date=2020-10-09|website=daplpipelinefacts.com}}</ref>\n\nAs more North American pipelines are built, even more exports of LNG, propane, butane, and other natural gas products occur on all three US coasts. To give insight, North Dakota Bakken region's oil production has grown by 600% from 2007 to 2015.<ref>{{cite report|url=https://www.eia.gov/petroleum/drilling/pdf/dpr-full.pdf|title=Drilling Productivity Report|date=November 2017|publisher=U.S. Energy Information Administration|access-date=21 November 2017}}</ref> North Dakota oil companies are shipping huge amounts of oil by tanker rail car as they can direct the oil to the market that gives the best price, and rail cars can be used to avoid a congested oil pipeline to get the oil to a different pipeline in order to get the oil to market faster or to a different less busy oil refinery. However, pipelines provide a cheaper means to transport by volume.\n\nEnbridge in Canada is applying to reverse an oil pipeline going from east-to-west (Line 9) and expanding it and using it to ship western Canadian bitumen oil eastward.<ref>{{cite web|url=https://www.thestar.com/projects/pipeline_journey.html |title=Line 9: Journey along the pipeline | Toronto Star |work=Thestar.com |date=2014-01-17 |access-date=2015-01-28}}</ref> From a presently rated 250,000 barrels equivalent per day pipeline, it will be expanded to between one million to 1.3 million barrels per day. It will bring western oil to refineries in Ontario, Michigan, Ohio, Pennsylvania, Quebec and New York by early 2014. New Brunswick will also refine some of this western Canadian crude and export some crude and refined oil to Europe from its deep water oil ULCC loading port.\n\nAlthough pipelines can be built under the sea, that process is economically and technically demanding, so the majority of oil at sea is transported by [[tanker (ship)|tanker ships]]. Similarly, it is often more economically feasible to transport natural gas in the form of LNG, however the break-even point between LNG and pipelines would depend on the volume of natural gas and the distance it travels.<ref>{{cite journal|last1=Ulvestad|first1= Marte|last2=Overland|first2=Indra|date=2012|title= Natural gas and CO2 price variation: Impact on the relative cost-efficiency of LNG and pipelines|journal=International Journal of Environmental Studies|volume=69|issue=3|pages=407\u2013426|pmc=3962073|doi= 10.1080/00207233.2012.677581|pmid= 24683269}}</ref>\n\n [[File:Gasoducto junto a la B-145, Chile, 2016-02-09, DD 36.JPG|thumb|Gas pipe in the dry region of Antofagasta, Chile.]]\nThe market size for oil and gas pipeline construction experienced tremendous\ngrowth prior to the economic downturn in 2008. After faltering in 2009, demand for pipeline expansion and updating increased the following year as energy production grew.<ref>[http://www.ibisworld.com/industry/default.aspx?indid=1977 "Oil & Gas Pipeline Construction in the U.S.: Market Research Report]," November 2012, IBISWorld.</ref> By 2012, almost 32,000 miles of North American pipeline were being planned or under construction.<ref name="pipelineandgasjournal.com">[http://www.pipelineandgasjournal.com/2012-worldwide-pipeline-construction-report "2012 Worldwide Pipeline Construction Report] {{Webarchive|url=https://web.archive.org/web/20130325081749/http://www.pipelineandgasjournal.com/2012-worldwide-pipeline-construction-report |date=2013-03-25 }}," ''Pipeline and Gas Journal'' '''239''' (1). January 2012.</ref> When pipelines are constrained, additional pipeline product transportation options may include the use of drag reducing agents, or by transporting product via truck or rail.\n\n Oil pipelines are made from [[steel]] or [[HDPE pipe|plastic tubes]] with inner diameter typically from {{convert|4|to|48|in}}. Most pipelines are typically buried at a depth of about {{convert|3|to|6|ft}}. To protect pipes from [[impact (mechanics)|impact]], [[abrasion (mechanical)|abrasion]], and [[corrosion]], a variety of methods are used. These can include [[wood lagging]] (wood slats), [[concrete]] coating, rockshield, [[HDPE pipe|high-density polyethylene]], imported sand padding, and padding machines.<ref name="asme">{{cite book\n| last = Mohitpour\n| first = Mo\n| title = Pipeline Design and Construction: A Practical Approach\n| publisher = ASME Press\n| year = 2003\n| isbn = 978-0791802021\n}}</ref>\n\nCrude oil contains varying amounts of [[paraffin wax]] and in colder climates wax buildup may occur within a pipeline. Often these pipelines are inspected and cleaned using [[pigging]], the practice of using devices known as "pigs" to perform various maintenance operations on a pipeline. The devices are also known as "scrapers" or "Go-devils". "Smart pigs" (also known as "intelligent" or "intelligence" pigs) are used to detect anomalies in the pipe such as dents, metal loss caused by corrosion, cracking or other mechanical damage.<ref>[http://www.thefreedictionary.com/go-devil go-devil \u2013 definition of go-devil] by the Free Online Dictionary, Thesaurus and Encyclopedia.</ref> These devices are launched from pig-launcher stations and travel through the pipeline to be received at any other station down-stream, either cleaning wax deposits and material that may have accumulated inside the line or inspecting and recording the condition of the line.\n\nFor natural gas, pipelines are constructed of carbon steel and vary in size from {{convert|2|to|60|in}} in diameter, depending on the type of pipeline. The gas is pressurized by [[compressor station]]s and is odorless unless mixed with a [[thiol|mercaptan odorant]] where required by a regulating authority.", "Pipeline transport --- Introduction ---|Water": "{{see also|Aqueduct (watercourse)|History of water supply and sanitation}}\n[[File:LA Aqueduct Antelope Valley.jpg|thumb|The [[Los Angeles Aqueduct]] in [[Antelope Valley]].]]\nTwo millennia ago, the [[Roman Empire|ancient Romans]] made use of large [[Roman aqueduct|aqueducts]] to transport water from higher elevations by building the aqueducts in graduated segments that allowed [[gravity]] to push the water along until it reached its destination. Hundreds of these were built throughout Europe and elsewhere, and along with [[flour mill]]s were considered the lifeline of the Roman Empire. The [[history of China|ancient Chinese]] also made use of channels and pipe systems for public works. The famous [[Han Dynasty]] court [[eunuch (court official)|eunuch]] [[Zhang Rang]] (d. 189 AD) once ordered the engineer Bi Lan to construct a series of square-pallet [[chain pump]]s outside the capital city of [[Luoyang]].<ref name="needham volume 4 part 2 33">Needham, Joseph (1986). Science and Civilization in China: Volume 4, Part 2. Taipei: Caves Books Ltd. p. 33.</ref> These chain pumps serviced the imperial [[palace]]s and living quarters of the capital city as the water lifted by the chain pumps was brought in by a [[stoneware]] [[pipe (material)|pipe]] system.<ref name="needham volume 4 part 2 33"/><ref name="needham volume 4 part 2 345 346">Needham, Volume 4, Part 2, 345\u201346.</ref>\n\nPipelines are useful for transporting water for [[drinking water|drinking]] or [[irrigation]] over long distances when it needs to move over [[hill]]s, or where [[canal]]s or [[channel (geography)|channels]] are poor choices due to considerations of [[evaporation]], [[pollution]], or environmental impact.\n\nThe {{convert|530|km|miles|abbr=on}} [[Goldfields Water Supply Scheme]] in [[Western Australia]] using 750 mm (30 inch) pipe and completed in 1903 was the largest water supply scheme of its time.<ref>[http://www.adb.online.anu.edu.au/biogs/A040174b.htm Mephan Ferguson] Australian Dictionary of Biography(online version)</ref><ref>[http://www.abc.net.au/dynasties/txt/s1489302.htm The Forrest family] {{Webarchive|url=https://web.archive.org/web/20160817224729/http://www.abc.net.au/dynasties/txt/s1489302.htm |date=2016-08-17 }} ''Dynasties'', ABC. Retrieved 17 September 2006.</ref>\n\nExamples of significant water pipelines in [[South Australia]] are the [[Morgan Whyalla pipeline|Morgan-Whyalla pipeline]] (completed 1944) and [[Mannum-Adelaide pipeline]] (completed 1955) pipelines, both part of the larger [[Snowy Mountains scheme]].<ref>{{cite web |url=http://www.sawater.com.au/SAWater/WhatsNew/NewsRoom/Mannum+Adelaide+Celebrations.htm |title=Mannum Adelaide Celebrations |publisher=SA Water |access-date=2015-01-28 |archive-url=https://web.archive.org/web/20150503090622/http://www.sawater.com.au/SAWater/WhatsNew/NewsRoom/Mannum+Adelaide+Celebrations.htm |archive-date=2015-05-03 |url-status=dead }}</ref>\n\nThere are two [[Los Angeles, California]] aqueducts, the ''[[Owens Valley aqueduct]]'' (completed 1913) and the ''[[Los Angeles aqueduct#Second Los Angeles Aqueduct|Second Los Angeles Aqueduct]]'' (completed 1970) which also include extensive use of pipelines.\n\nThe [[Great Manmade River]] of Libya supplies {{convert|3680000|m3|cuyd}} of water each day to Tripoli, Benghazi, Sirte, and several other cities in Libya. The pipeline is over {{convert|2800|km|mi}} long, and is connected to wells tapping an aquifer over {{convert|500|m|ft}} underground.<ref>{{cite web\n|url=http://www.water-technology.net/projects/gmr/\n|title=GMR (Great Man-Made River) Water Supply Project, Libya\n|access-date=Apr 15, 2012\n|publisher=water-technology.net}}\n</ref>"}},
{"article_title": "Slow-scan television", "pageid": "51210", "revid": "1062630304", "timestamp": "2021-12-29T16:16:58Z", "history_paths": [["Slow-scan television --- Introduction ---", "History"]], "categories": ["amateur radio", "radio modulation modes", "television technology"], "heading_tree": {"Slow-scan television --- Introduction ---": {"History": {"Concept": {}, "Early usage in space exploration": {}, "Progression": {}}, "Current systems": {"Modulation": {}, "Header": {}, "Scanlines": {}, "Modes": {"AVT": {}, "Other modes": {}}, "Frequencies": {}}, "Media": {}, "In popular culture": {}, "See also": {}, "References": {"Notes": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Slow-scan television --- Introduction ---|History": "The concept of SSTV was introduced by Copthorne Macdonald<ref>{{Cite web|url=http://www.copmacdonald.com/|title=Copthorne Macdonald's Home Page|date=January 2, 2014|archive-url=https://web.archive.org/web/20140102230922/http://www.copmacdonald.com/|archive-date=2014-01-02}}</ref> in 1957–58.<ref name="Miller">{{cite web | url = http://www.darc.de/distrikte/g/T_ATV/sstv-history.htm | title = SSTV history | author = Miller, Don | access-date = May 9, 2006 }}</ref> He developed the first SSTV system using an electrostatic monitor and a [[video camera tube#Vidicon|vidicon tube]]. It was deemed sufficient to use 120 lines and about 120 pixels per line to transmit a black-and-white still picture within a 3 kHz telephone channel. First live tests were performed on the 11-meter ham band{{snd}} which was later given to the [[Citizen's band radio|CB]] service in the US. In the 1970s, two forms of paper printout receivers were invented by [[Amateur radio operator|hams]].\n\n [[File:S63-07856.jpg|thumb|Astronaut Gordon Cooper, SSTV transmission from Faith 7]]\n\nSSTV was used to transmit images of the far side of the Moon from [[Luna 3]].<ref>[http://astrosurf.com/nunes/explor/explor_luna3.htm Luna 3<!-- Bot generated title -->]. {{webarchive|url=https://web.archive.org/web/20070929083752/http://astrosurf.com/nunes/explor/explor_luna3.htm |date=2007-09-29 }}.</ref>\n\nThe first space television system was called [[Seliger-Tral-D]] and was used aboard [[Vostok (spacecraft)|Vostok]]. Vostok was based on an earlier [[videophone]] project which used two cameras, with persistent LI-23 [[iconoscope]] tubes. Its output was 10 frames per second at 100 lines per frame video signal.\n\n* The Seliger system was tested during the 1960 launches of the [[Vostok (spacecraft)|Vostok]] capsule, including [[Sputnik 5]], containing the space dogs [[Belka (dog)|Belka]] and [[Strelka (dog)|Strelka]], whose images are often mistaken for the dog [[Laika]], and the 1961 flight of [[Yuri Gagarin]], the first man in space on [[Vostok 1]].\n* [[Vostok 2]] and thereafter used an improved 400-line television system referred to as [[Topaz (television)|Topaz]].\n* A second generation system ([[Krechet]], incorporating docking views, overlay of docking data, etc.) was introduced after 1975.\n\nA similar concept, also named ''SSTV'', was used on [[Mercury-Atlas 9|Faith 7]],<ref name="MercuryRadio">{{cite web |url=http://www.svengrahn.pp.se/radioind/Mercury/MercuryRadio.html |title=The Mercury-Atlas-9 slow-scan TV experiment |author=Sven Grahn |website=Space Radio Notes}}</ref> as well as on the early years of the [[NASA]] [[Project Apollo|Apollo]] program.\n* The Faith 7 camera transmitted one frame every two seconds, with a resolution of 320 lines.<ref name="MercuryRadio"/>\n\t\n[[File:Apollo 11 first step.jpg|thumb|left|NASA slow-scan image from the Moon]]\nThe [[Apollo TV camera]]s used SSTV to transmit images from inside [[Apollo 7]], [[Apollo 8]], and [[Apollo 9]], as well as the [[Apollo 11]] [[Apollo Lunar Module|Lunar Module]] television from the [[Moon]]. NASA had taken all the original tapes and erased them for use on subsequent missions; however, the [[Apollo 11 missing tapes|Apollo 11 Tape Search and Restoration Team]] formed in 2003 tracked down the highest-quality films among the converted recordings of the first broadcast, pieced together the best parts, then contracted a specialist [[film restoration]] company to enhance the degraded black-and-white film and convert it into [[Digital data|digital]] format for [[Archive|archival records]].<ref>{{cite web\n|url= http://www.cosmosmagazine.com/news/3827/lost-apollo-tapes-restored-and-broadcast\n|title= 'Lost' Apollo 11 Moonwalk tapes restored\n|access-date= 4 November 2010\n|author= Andrew Letten\n|date= 2010-10-26\n|publisher= [[Cosmos (magazine)|Cosmos Online]]\n|url-status=dead\n|archive-url=https://web.archive.org/web/20140720193330/http://cosmosmagazine.com/news/lost-apollo-tapes-restored-and-broadcast/\n|archive-date=July 20, 2014\n|quote= SYDNEY: After a three-year search for the lost Apollo 11 tapes and an exhaustive six-year restoration project, digitally remastered footage of the historic Moonwalk is almost ready to be broadcast.\n}}</ref> \n* The SSTV system used in [[NASA]]'s early Apollo missions transferred 10 frames per second with a resolution of 320 frame lines in order to use less bandwidth than a normal TV transmission.{{citation needed|date=December 2019}}\n* The early SSTV systems used by NASA differ significantly from the SSTV systems currently in use by amateur radio enthusiasts today.\n\n Commercial systems started appearing in the United States in 1970, after the [[Federal Communications Commission|FCC]] had legalized the use of SSTV for [[Amateur radio licensing in the United States|advanced level]] amateur radio operators in 1968.\n\nSSTV originally required quite a bit of specialized equipment. Usually there was a scanner or camera, a modem to create and receive the characteristic [[sound reproduction|audio]] howl, and a [[cathode-ray tube]] from a surplus [[radar]] set. The special cathode-ray tube would have "long persistence" [[phosphor]]s that would keep a picture visible for about ten seconds.\n\nThe [[modem]] would generate audio tones between 1,200 and 2,300 Hz from picture signals, and picture signals from received audio tones. The audio would be attached to a radio [[receiver (radio)|receiver]] and [[transmitter]]."}},
{"article_title": "Seat belt", "pageid": "51474", "revid": "1062328687", "timestamp": "2021-12-27T20:18:44Z", "history_paths": [["Seat belt --- Introduction ---", "History"]], "categories": ["vehicle safety technologies", "english inventions", "safety equipment", "seat belts", "vehicle parts"], "heading_tree": {"Seat belt --- Introduction ---": {"Effectiveness": {}, "History": {}, "Types": {"Two-point": {"Lap": {}, "Sash": {}}, "Three-point": {"Belt-in-Seat": {}}, "4-, 5-, and 6-point": {}, "Seven-point": {}, "Seatbelt airbag": {}}, "Technology": {"Locking retractors": {}, "Pretensioners and webclamps": {}, "Inflatable": {}, "Automatic": {"Systems": {}, "Disadvantages": {}}}, "Homologation and testing": {}, "Experimental": {}, "In rear seats": {}, "Child occupants": {}, "Automated reminders and engine start interlocks": {"US regulation history": {}, "Efficacy": {}, "Delayed start": {}}, "Regulation by country": {"International regulations": {}, "Local regulations": {}}, "Legislation": {"Risk compensation": {}, "Increased traffic": {}}, "Mass transit considerations": {"Buses": {"School buses": {}, "Motor coaches": {}}, "Trains": {}, "Airplanes": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Seat belt --- Introduction ---|History": "Seatbelts were invented by English engineer [[George Cayley]] to use on his glider, in the mid-19th century.<ref>{{cite news |url= http://www.yorkshirepost.co.uk/features/Clunk-click--an-invention.5583475.jp?articlepage=1 |title=Clunk, click \u2013 an invention that's saved lives for 50 years |last=Manby |first=Frederic |date=24 August 2009 |access-date=2010-12-04 |publisher=Johnston Press Digital Publishing |newspaper=Yorkshire Post|url-status=dead |archive-url=https://web.archive.org/web/20160102042045/http://www.yorkshirepost.co.uk/news/analysis/clunk-click-an-invention-that-s-saved-lives-for-50-years-1-2296965 |archive-date=January 2, 2016}}</ref>\n\nIn 1946, Dr. C. Hunter Shelden opened a neurological practice at [[Huntington Memorial Hospital]] in [[Pasadena, California]]. In the early 1950s, Shelden made a major contribution to the automotive industry with his idea of retractable seat belts. This came about from his care of the high number of head injuries coming through the emergency room.<ref>{{cite web |url= http://www.hmri.org/HMRI_News/HMRI_News_-_May_2003/Shelden_Memorial/shelden_memorial.html |title=HMRI News |publisher=Hmri.org |access-date=2011-02-02 |url-status=dead |archive-url= https://web.archive.org/web/20110226051243/http://www.hmri.org/HMRI_News/HMRI_News_-_May_2003/Shelden_Memorial/shelden_memorial.html |archive-date=February 26, 2011 }}</ref> He investigated the early seat belts whose primitive designs were implicated in these injuries and deaths. \n\n[[Nash Motors|Nash]] was the first American car manufacturer to offer seat belts as a factory option in its 1949 models.<ref>{{cite web |last1=Janik |first1=Erika |title=The Surprisingly Controversial History Of Seat Belts |url= https://www.wpr.org/surprisingly-controversial-history-seat-belts |website=Wisconsin Public Radio |date=September 25, 2017 |access-date=January 11, 2021}}</ref> They were installed in 40,000 cars, but buyers did not want them and requested dealers to remove them.<ref name="Nash-1949">{{cite book |last1=Ronan |first1=Larry |title=Seatbelts: 1949-1956 |date=April 1979 |publisher=US Department of Transportation, National Highway Traffic Safety Administration (DOT-TSC-NHTSA-79-1) |page=17}}</ref> The feature was "met with insurmountable sales resistance" and Nash reported that after one year "only 1,000 had been used" by customers.<ref name="Nash-1949"/>\n\nFord offered seat belts as an option in 1955. These were not popular, with only 2% of Ford buyers choosing to pay for seatbelts in 1956.<ref name="MSN Before face masks">{{cite news |title=Before face masks, Americans went to war against seat belts |first=Daniel |last=Ackerman |url= https://www.msn.com/en-us/news/us/before-face-masks-americans-went-to-war-against-seat-belts/ar-BB14CsNG |work=www.msn.com |date=26 May 2020 |access-date=5 September 2020 |archive-url=https://web.archive.org/web/20201120224357/https://www.msn.com/en-us/news/us/before-face-masks-americans-went-to-war-against-seat-belts/ar-BB14CsNG |archive-date=2020-11-20 |url-status=dead}}</ref>\n\nTo reduce the high level of injuries Shelden was seeing, he proposed, in late 1955, retractable seat belts, recessed [[steering wheel]]s, reinforced roofs, [[roll cage|roll bars]], automatic door locks, and passive restraints such as the [[air bag]].<ref name="JAMA">{{cite journal |title=Prevention, the only cure for head injuries resulting from automobile accidents |first=C. Hunter |last=Shelden |journal=Journal of the American Medical Association |volume=159 |issue=10 |pages=981\u20136 |date=November 5, 1955 |doi=10.1001/jama.1955.02960270001001 |pmid=13263134 }}</ref> Subsequently, in 1966, Congress passed the [[National Traffic and Motor Vehicle Safety Act]] requiring all automobiles to comply with certain safety standards.\n\nGlenn W. Sheren, of [[Mason, Michigan]], submitted a patent application on March 31, 1955 for an automotive seat belt and was awarded US Patent 2,855,215 in 1958. This was a continuation of an earlier patent application that Sheren had filed on September 22, 1952.<ref>{{cite web |url=http://www.freepatentsonline.com/2855215.html |title=Automobile safety belt system - Patent 2855215 |publisher=Freepatentsonline.com |date=1958-10-07 |access-date=2011-04-03 |archive-url= https://web.archive.org/web/20121013054127/http://www.freepatentsonline.com/2855215.html |archive-date=2012-10-13 |url-status=dead }}</ref>\n\nHowever, the first modern three-point seat belt (the so-called ''CIR-Griswold restraint'') used in most consumer vehicles today was patented in 1955 {{US patent |2,710,649}} by the Americans Roger W. Griswold and [[Hugh DeHaven]].\n\n[[Saab Automobile|Saab]] introduced seat belts as standard equipment in 1958.<ref name="independent.co.uk">{{cite news |url= https://www.independent.co.uk/life-style/gadgets-and-tech/features/the-man-who-saved-a-million-lives-nils-bohlin--inventor-of-the-seatbelt-1773844.html |title=The man who saved a million lives: Nils Bohlin - inventor of the seat belt |newspaper=The Independent |date=2009-08-19 |access-date=2009-12-08}}</ref> After the [[Saab GT750|Saab GT 750]] was introduced at the New York Motor Show in 1958 with safety belts fitted as standard, the practice became commonplace.<ref>{{cite web |url= http://www.trollhattansaab.net/page/5 |title=Trollhattan Saab\u2014Saab 9-1, 9-3, 9-4x, 9-5, 9-7x News |publisher=Trollhattansaab.net |access-date=2011-02-02 |archive-url= https://web.archive.org/web/20110227041041/http://www.trollhattansaab.net/page/5 |archive-date=2011-02-27 |url-status=dead }}</ref>\n\n[[Vattenfall]], the Swedish national electric utility, did a study of all fatal, on-the-job accidents among their employees. The study revealed that the majority of fatalities occurred while the employees were on the road on company business. In response, two Vattenfall safety engineers, Bengt Odelgard and Per-Olof Weman, started to develop a seat belt. Their work was presented to Swedish manufacturer [[Volvo]] in the late 1950s, and set the standard for seat belts in Swedish cars.<ref>{{cite book|last1=Andr\u00e9asson |first1=Rune |first2=Claes-G\u00f6ran |last2=B\u00e4ckstr\u00f6m |location=Stockholm |publisher=Kulturv\u00e5rdskommitt\u00e9n Vattenfall AB |year=2000 |title=The Seat Belt: Swedish Research and Development for Global Automotive Safety |isbn=9789163093890 |pages=9, 15\u201316}}</ref> The three-point seatbelt was developed to its modern form by Swedish inventor [[Nils Bohlin]] for Volvo—who introduced it in 1959 as standard equipment. In addition to designing an effective three-point belt, Bohlin demonstrated its effectiveness in a study of 28,000 accidents in Sweden. Unbelted occupants sustained fatal injuries throughout the whole speed scale, whereas none of the belted occupants were fatally injured at accident speeds below 60 mph. No belted occupant was fatally injured if the passenger compartment remained intact.<ref>{{cite conference|url= https://www.sae.org/publications/technical-papers/content/670925/ |title =A Statistical Analysis of 28,000 Accidents with Emphasis on Occupant Restraint Value |first=Nils I. |last=Bohlin |year =1967 |conference=11th Stapp Car Crash Conference |publisher=Society of Automotive Engineers |id=SAE Technical Paper 670925 |doi=10.4271/670925 |access-date=5 September 2020}}</ref> Bohlin was granted {{US patent |3,043,625}} for the device.<ref name="independent.co.uk"/>\n\nThe first compulsory [[seat belt law]] was put in place in 1970, in the state of [[Victoria, Australia]], requiring their use by drivers and front-seat passengers. This legislation was enacted after trialing Hemco seatbelts, designed by Desmond Hemphill (1926\u20132001), in the front seats of police vehicles, lowering the incidence of officer injury and death.<ref>{{cite web |title=A Potted Seat Belt History |publisher=Drivers Technology |url= http://www.driverstechnology.co.uk/seatbelts.htm |access-date=2009-09-06 |archive-url= https://web.archive.org/web/20080514220650/http://www.driverstechnology.co.uk/seatbelts.htm |archive-date=2008-05-14 |url-status=dead}}</ref> Mandatory seatbelt laws in the United States began to be introduced in the 1980s and faced opposition, with some consumers going to court to challenge the laws. Some cut seatbelts out of their cars.<ref name="MSN Before face masks"/>"}},
{"article_title": "Motion compensation", "pageid": "52035", "revid": "1054551784", "timestamp": "2021-11-10T18:26:36Z", "history_paths": [["Motion compensation --- Introduction ---", "History"]], "categories": ["film and video technology", "h.26x", "video compression", "motion in computer vision"], "heading_tree": {"Motion compensation --- Introduction ---": {"Functionality": {}, "Illustrated example": {}, "MPEG": {}, "Global motion compensation": {}, "Motion-compensated DCT": {"Block motion compensation": {}, "Variable block-size motion compensation": {}, "Overlapped block motion compensation": {}}, "Quarter Pixel (QPel) and Half Pixel motion compensation": {}, "3D image coding techniques": {}, "History": {"Motion-compensated DCT": {}}, "See also": {}, "Applications": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Motion compensation --- Introduction ---|History": "{{Main|Video coding format}}\n\nA precursor to the concept of motion compensation dates back to 1929, when R.D. Kell in Britain proposed the concept of transmitting only the portions of an [[analog video]] scene that changed from frame-to-frame. The concept of [[inter-frame]] motion compensation dates back to 1959, when [[NHK]] researchers Y. Taki, M. Hatori and S. Tanaka proposed predictive inter-frame [[video coding]] in the [[temporal dimension]].<ref name="ITU">{{cite web |title=History of Video Compression |url=https://www.itu.int/wftp3/av-arch/jvt-site/2002_07_Klagenfurt/JVT-D068.doc |website=[[ITU-T]] |publisher=Joint Video Team (JVT) of ISO/IEC MPEG & ITU-T VCEG (ISO/IEC JTC1/SC29/WG11 and ITU-T SG16 Q.6) |date=July 2002 |pages=11, 24-9, 33, 40-1, 53-6 |access-date=3 November 2019}}</ref>\n\n Practical motion-compensated [[video compression]] was made possible by the development of motion-compensated [[Discrete cosine transform|DCT]] (MC DCT) coding,<ref name="Lea">{{cite book |last1=Lea |first1=William |title=Video on demand: Research Paper 94/68 |date=1994 |publisher=[[House of Commons Library]] |location=9 May 1994 |url=https://researchbriefings.parliament.uk/ResearchBriefing/Summary/RP94-68 |access-date=20 September 2019 |archive-url=https://web.archive.org/web/20190920082623/https://researchbriefings.parliament.uk/ResearchBriefing/Summary/RP94-68 |archive-date=20 September 2019 |url-status=dead }}</ref> also called block motion compensation (BMC) or DCT motion compensation. This is a hybrid coding algorithm,<ref name="ITU"/> which combines two key [[data compression]] techniques: [[discrete cosine transform]] (DCT) coding<ref name="Lea"/> in the [[spatial dimension]], and predictive motion compensation in the [[temporal dimension]].<ref name="ITU"/> DCT coding is a [[lossy compression|lossy]] block compression [[transform coding]] technique that was first proposed by [[N. Ahmed|Nasir Ahmed]], who initially intended it for [[image compression]], in 1972.<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I Came Up With the Discrete Cosine Transform |journal=[[Digital Signal Processing (journal)|Digital Signal Processing]] |date=January 1991 |volume=1 |issue=1 |pages=4\u20135 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform}}</ref>\n\nIn 1974, Ali Habibi at the [[University of Southern California]] introduced hybrid coding,<ref>{{cite journal |last1=Habibi |first1=Ali |title=Hybrid Coding of Pictorial Data |journal=IEEE Transactions on Communications |date=1974 |volume=22 |issue=5 |pages=614\u2013624 |doi=10.1109/TCOM.1974.1092258}}</ref><ref>{{cite journal |last1=Chen |first1=Z. |last2=He |first2=T. |last3=Jin |first3=X. |last4=Wu |first4=F. |title=Learning for Video Compression |journal=IEEE Transactions on Circuits and Systems for Video Technology |volume=30 |issue=2 |pages=566\u2013576 |doi=10.1109/TCSVT.2019.2892608 |arxiv=1804.09869 |year=2020 |s2cid=13743007 }}</ref> which combines predictive coding with transform coding.<ref name="ITU"/><ref>{{cite book |last1=Ohm |first1=Jens-Rainer |title=Multimedia Signal Coding and Transmission |date=2015 |publisher=Springer |isbn=9783662466919 |pages=364 |url=https://books.google.com/books?id=e7xnBwAAQBAJ&pg=PA364}}</ref> However, his algorithm was initially limited to [[intra-frame]] coding in the spatial dimension. In 1975, John A. Roese and Guner S. Robinson extended Habibi's hybrid coding algorithm to the temporal dimension, using transform coding in the spatial dimension and predictive coding in the temporal dimension, developing [[inter-frame]] motion-compensated hybrid coding.<ref name="ITU"/><ref name="Roese">{{cite journal |last1=Roese |first1=John A. |last2=Robinson |first2=Guner S. |title=Combined Spatial And Temporal Coding Of Digital Image Sequences |journal=Efficient Transmission of Pictorial Information |date=30 October 1975 |volume=0066 |pages=172\u2013181 |doi=10.1117/12.965361 |bibcode=1975SPIE...66..172R |publisher=International Society for Optics and Photonics|s2cid=62725808 }}</ref> For the spatial transform coding, they experimented with the DCT and the [[fast Fourier transform]] (FFT), developing inter-frame hybrid coders for both, and found that the DCT is the most efficient due to its reduced complexity, capable of compressing image data down to 0.25-[[bit]] per [[pixel]] for a [[videotelephone]] scene with image quality comparable to an intra-frame coder requiring 2-bit per pixel.<ref>{{cite book |last1=Huang |first1=T. S. |title=Image Sequence Analysis |date=1981 |publisher=[[Springer Science & Business Media]] |isbn=9783642870378 |page=29 |url=https://books.google.com/books?id=bAirCAAAQBAJ&pg=PA29}}</ref><ref name="Roese"/>\n\nIn 1977, Wen-Hsiung Chen developed a fast DCT algorithm with C.H. Smith and S.C. Fralick.<ref>{{cite journal |last1=Chen |first1=Wen-Hsiung |last2=Smith |first2=C. H. |last3=Fralick |first3=S. C. |title=A Fast Computational Algorithm for the Discrete Cosine Transform |journal=[[IEEE Transactions on Communications]] |date=September 1977 |volume=25 |issue=9 |pages=1004\u20131009 |doi=10.1109/TCOM.1977.1093941}}</ref> In 1979, [[Anil K. Jain (electrical engineer, born 1946)|Anil K. Jain]] and Jaswant R. Jain further developed motion-compensated DCT video compression,<ref>{{cite book |last1=Cianci |first1=Philip J. |title=High Definition Television: The Creation, Development and Implementation of HDTV Technology |date=2014 |publisher=McFarland |isbn=9780786487974 |page=63 |url=https://books.google.com/books?id=0mbsfr38GTgC&pg=PA63}}</ref><ref name="ITU"/> also called block motion compensation.<ref name="ITU"/> This led to Chen developing a practical video compression algorithm, called motion-compensated DCT or adaptive scene coding, in 1981.<ref name="ITU"/> Motion-compensated DCT later became the standard coding technique for video compression from the late 1980s onwards.<ref name="Ghanbari">{{cite book |last1=Ghanbari |first1=Mohammed |title=Standard Codecs: Image Compression to Advanced Video Coding |date=2003 |publisher=[[Institution of Engineering and Technology]] |isbn=9780852967102 |pages=1\u20132 |url=https://books.google.com/books?id=7XuU8T3ooOAC&pg=PA1}}</ref><ref name="Li">{{cite book |last1=Li |first1=Jian Ping |title=Proceedings of the International Computer Conference 2006 on Wavelet Active Media Technology and Information Processing: Chongqing, China, 29-31 August 2006 |date=2006 |publisher=[[World Scientific]] |isbn=9789812709998 |page=847 |url=https://books.google.com/books?id=FZiK3zXdK7sC&pg=PA847}}</ref>\n\nThe first digital [[video coding standard]] was [[H.120]], developed by the [[ITU-T|CCITT]] (now ITU-T) in 1984.<ref name="history">{{cite web |title=The History of Video File Formats Infographic |url=http://www.real.com/resources/digital-video-file-formats/ |website=[[RealNetworks]] |access-date=5 August 2019 |date=22 April 2012}}</ref> H.120 used motion-compensated DPCM coding,<ref name="ITU"/> which was inefficient for video coding,<ref name="Ghanbari"/> and H.120 was thus impractical due to low performance.<ref name="history"/> The [[H.261]] standard was developed in 1988 based on motion-compensated DCT compression,<ref name="Ghanbari"/><ref name="Li"/> and it was the first practical video coding standard.<ref name="history"/> Since then, motion-compensated DCT compression has been adopted by all the major video coding standards (including the [[H.26x]] and [[MPEG]] formats) that followed.<ref name="Ghanbari"/><ref name="Li"/>"}},
{"article_title": "Fork", "pageid": "52501", "revid": "1060009010", "timestamp": "2021-12-12T23:36:19Z", "history_paths": [["Fork --- Introduction ---", "History"]], "categories": ["eating utensils", "forks", "ancient egyptian technology", "ancient roman technology", "chinese inventions"], "heading_tree": {"Fork --- Introduction ---": {"History": {}, "Types of fork": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Fork --- Introduction ---|History": "[[File:Forks Susa Louvre MAO421-422-431.jpg|left|250px|thumb|Bronze forks made in Persia during the 8th or 9th century.]]\nBone forks have been found in archaeological sites of the [[Bronze Age]] [[Qijia culture]] (2400\u20131900 BC), the [[Shang dynasty]] (c. 1600\u2013c. 1050 BC), as well as later Chinese dynasties.<ref name=need6V>Needham (2000). ''Science and Civilisation in China. Volume 6: Biology and biological technology. Part V: Fermentations and food science.'' Cambridge University Press. Pages 105\u2013110.</ref> A stone carving from an [[Eastern Han]] tomb (in Ta-kua-liang, Suide County, Shaanxi) depicts three hanging two-pronged forks in a dining scene.<ref name=need6V/> Similar forks have also been depicted on top of a stove in a scene at another Eastern Han tomb (in Suide County, Shaanxi).<ref name=need6V/>\n\nIn [[Ancient Egypt]], large forks were used as cooking utensils.<ref name="leitesculinaria">{{cite web | url=http://leitesculinaria.com/1157/writings-the-uncommon-origins-of-the-common-fork.html | title=The Uncommon Origins of the Common Fork | publisher=Leite's Culinaria | author=Ward, Chad | date=6 May 2009}}</ref>\n\nIn the [[Roman Empire]], [[bronze]] and silver forks were used, many surviving examples of which are displayed in museums around Europe.<ref>{{cite web |url=http://www.fitzmuseum.cam.ac.uk/opac/search/cataloguedetail.html?&priref=70534&_function_=xslt&_limit_=10 |title=Fitzwilliam Museum \u2013 A combination Roman eating implement |url-status=dead |archive-url=https://web.archive.org/web/20081207064108/http://www.fitzmuseum.cam.ac.uk/opac/search/cataloguedetail.html?&priref=70534&_function_=xslt&_limit_=10 |archive-date=7 December 2008 }}</ref><ref>Sherlock, D. (1988) A combination Roman eating implement (1988). Antiquaries Journal [comments: 310\u2013311, pl. xlix]</ref> Use varied according to local customs, social class, and the type of food, but in earlier periods forks were mostly used as cooking and serving utensils.\n\nAlthough its origin may go back to [[Ancient Greece]], the personal table fork was most likely invented in the [[Eastern Roman Empire|Eastern Roman]] (''Byzantine'') Empire, where they were in common use by the 4th century.<ref name="Ancient inventions">{{cite book|title=Ancient inventions |author1=James, Peter |author2=Thorpe, Nick |author3=Thorpe, I. J. | url=https://books.google.com/books?id=VmJLd3sSYecC | publisher=Ballantine Books | year= 1995 |page=305|isbn=978-0-345-40102-1}}</ref><ref>{{cite book |title=Firsts: Origins of Everyday Things that Changed the World |isbn=978-1-59257-924-2 |author=Casey, Wilson |publisher=Penguin |year=2009 |edition=F }}</ref>  \nRecords show that by the 9th century in some elite circles of Persia a similar utensil known as a ''barjyn'' was in limited use.<ref>{{cite book |title=A Mediterranean Feast: The Story of the Birth of the Celebrated Cuisines of the Mediterranean from the Merchants of Venice to the Barbary Corsairs, with More than 500 Recipes |author=Wright, Clifford A. |publisher=William Morrow Cookbooks |year=1999 |isbn=978-0-688-15305-2 |page=[https://archive.org/details/mediterraneanfea00wrig/page/82 82] |url-access=registration |url=https://archive.org/details/mediterraneanfea00wrig/page/82 }}</ref> By the 10th century, the table fork was in common use throughout the Middle East.<ref name="leitesculinaria"/> According to [[Peter Damian]], the Byzantine princess [[Maria Argyropoulina]] brought some golden forks to Venice, when she married the son of the [[Doge]] in 1004. Damien condemned the fork as "vanity".<ref>[https://www.books.fr/fourchette-bonnes-manieres/ Amandine Meunier, "Fourchette et bonnes mani\u00e8res",  Books n\u00b0 86, novembre / d\u00e9cembre 2017, Books.fr]</ref>\n\nBy the 11th century, the table fork had become increasingly prevalent in the [[Italian peninsula]] before other European regions because of historical ties with [[Byzantium]] and, as [[pasta]] became a greater part of the Italian diet, continued to gain popularity, displacing the long wooden spike formerly used since the fork's three spikes proved better suited to gathering the noodles.<ref name=Rebora2013>{{cite book |last=Rebora |first=Giovanni |title=Culture of the Fork: A Brief History of Everyday Food and Haute Cuisine in Europe |url=https://books.google.com/books?id=tRs2ObI7ozoC&pg=PA14 |year=2013 |publisher=Columbia University Press |isbn=978-0-231-51845-1 |pages=14\u201318}}</ref><ref name="Wilson, Bee 2012">Wilson, Bee. Consider the Fork: A History of How We Cook and Eat. New York: Basic, 2012. Print.</ref> By the 14th century the table fork had become commonplace in Italy, and by 1600 was almost universal among the merchant and upper classes. It was proper for a guest to arrive with his own fork and [[spoon]] enclosed in a box called a ''cadena''; this usage was introduced to the French court with [[Catherine de' Medici]]'s entourage.\nAlthough in Portugal forks were first used around 1450 by [[Infanta Beatrice, Duchess of Viseu]], King [[Manuel I of Portugal]]'s mother,<ref>{{cite web |url=http://www.cm-loures.pt/Agenda_out11_PMes.asp |title=Livro de Cozinha da Infanta D. Maria |url-status=dead |archive-url=https://web.archive.org/web/20111130071645/http://www.cm-loures.pt/Agenda_out11_PMes.asp |archive-date=30 November 2011 }}</ref> only by the 16th century, when they had become part of Italian [[etiquette]], did forks enter into common use in [[Southern Europe]],<ref>{{cite book |author=Rautman, Marcus Louis |title=Daily life in the Byzantine Empire |url=https://books.google.com/books?id=hs3iEyVRHKsC |publisher=Greenwood |year=2006 |isbn=978-0-313-32437-6 |page=47}}</ref> gaining some currency in Spain,<ref>{{cite web |url=http://www.hospitalityguild.com/History/Table_Forks_of_the_Medieval&Renaissance.htm |title=Table Forks of the Medieval & Renaissance Period |publisher=The International Guild of Hospitality & Restaurant Managers |access-date=8 December 2011}}</ref> and gradually spreading to France. The rest of Europe did not adopt the fork until the 18th century.<ref name="Ancient inventions"/>\n[[File:History spoon.jpg|right|230px|thumb|[[Sasanian Empire|Sasanian]] silver fork (4th century)]]\nThe fork's adoption in northern Europe was slower. Its use was first described in English by [[Thomas Coryat]] in a volume of writings on his Italian travels (1611), but for many years it was viewed as an unmanly Italian affectation.{{sfn |Petroski |1992 |pp=8\u22129}} Some writers of the Roman Catholic Church expressly disapproved of its use; [[St. Peter Damian]] seeing it as "excessive delicacy".<ref name="Wilson, Bee 2012"/> It was not until the 18th century that the fork became commonly used in Great Britain,<ref>{{citation|author=Charing Worh|title=Types of Cutlery in the UK|url=http://www.charingworth.net/GB/shop/about-charingworth-cutlery.html|access-date=24 March 2014|year=2014|publisher=Charing Worth}}</ref> although some sources say that forks were common in France, England and Sweden already by the early 17th century.<ref>[http://www.bookrags.com/research/knife-fork-and-spoon-woi/ bookrags.com]. bookrags.com (2 November 2010). {{tertiary}}</ref><ref>{{cite web|author=Anette Rasmsson |url=http://www.popularhistoria.se/o.o.i.s?id=170&vid=707 |title=popularhistoria.se at archive.org |archive-url = https://web.archive.org/web/20100731165816/http://www.popularhistoria.se/o.o.i.s?id=170&vid=707|access-date=2019-02-06|archive-date = 31 July 2010}}</ref>{{dubious|reason=Unreliable sources cited for the 17th century assertion|date=January 2015}}\n\nThe fork did not become popular in North America until near the time of the [[American Revolution]].<ref name="leitesculinaria"/> The standard four-tine design became current in the early 19th century.<ref>{{Cite book|title=Encyclopedia of American Food and Drink|last=Mariani|first=John F.|publisher=Bloomsbury|year=2014|location=London, UK|via=Credo Reference}}</ref>"}},
{"article_title": "Digital camera", "pageid": "52797", "revid": "1062686174", "timestamp": "2021-12-29T23:01:16Z", "history_paths": [["Digital camera --- Introduction ---", "History"]], "categories": ["digital cameras", "cameras", "american inventions", "audiovisual introductions in 1975", "1975 in the arts", "1975 in technology", "computer-related introductions in 1975", "20th-century inventions"], "heading_tree": {"Digital camera --- Introduction ---": {"History": {}, "Image sensors": {"Sensor resolution": {"Resolution options": {}}, "Image sharpness": {}, "Methods of image capture": {}, "Filter mosaics, interpolation, and aliasing": {}, "Sensor size and angle of view": {}}, "Types of digital cameras": {"[[Point and shoot camera|Compacts]]": {}, "Rugged compacts": {}, "Action cameras": {}, "360-degree cameras": {}, "Bridge cameras": {}, "Mirrorless interchangeable-lens cameras": {}, "Modular cameras{{anchor|Smart Lens}}": {}, "Digital single-lens reflex cameras (DSLR)": {}, "Digital Still Cameras (DSC)": {}, "Fixed-mirror DSLT cameras": {}, "Digital rangefinders": {}, "Line-scan camera systems": {}, "Stand alone camera": {}, "Superzoom Cameras": {}, "[[Light-field camera]]": {}}, "Integration into other devices": {}, "Example of Camera Manufacturers": {"Notable Digital Camera Manufacturers": {}}, "Market trends": {}, "Connectivity": {"Transferring photos": {}, "Printing photos": {}, "Displaying photos": {}}, "Weather-sealing and waterproofing": {}, "Modes": {"Scene modes": {}}, "Image data storage": {"File formats": {}, "Directory and file structure": {}, "Thumbnail files": {}}, "Batteries": {"Proprietary": {}, "Standard consumer batteries": {}}, "Conversion of film cameras to digital": {"Digital camera backs": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Digital camera --- Introduction ---|History": "{{See|History of the camera#Digital cameras|Digital imaging|Digital single-lens reflex camera|Camera phone}}\n\nThe basis for digital camera [[image sensors]] is [[metal\u2013oxide\u2013semiconductor]] (MOS) technology,<ref name="Cressler">{{cite book |last1=Cressler |first1=John D. |title=Silicon Earth: Introduction to Microelectronics and Nanotechnology, Second Edition |date=2017 |publisher=[[CRC Press]] |isbn=978-1-351-83020-1 |chapter=Let There Be Light: The Bright World of Photonics |page=29 |chapter-url=https://books.google.com/books?id=i-5HDwAAQBAJ&pg=SA12-PA29}}</ref><ref name="Williams">{{cite book |last1=Williams |first1=J. B. |title=The Electronics Revolution: Inventing the Future |date=2017 |publisher=Springer |isbn=978-3-319-49088-5 |pages=245\u20138 |url=https://books.google.com/books?id=v4QlDwAAQBAJ&pg=PA245}}</ref> which originates from the invention of the [[MOSFET]] (MOS field-effect transistor) by [[Mohamed M. Atalla]] and [[Dawon Kahng]] at [[Bell Labs]] in 1959.<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960: Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]] |access-date=August 31, 2019}}</ref> This led to the development of digital [[semiconductor]] image sensors, including the [[charge-coupled device]] (CCD) and later the [[CMOS sensor]].<ref name="Williams" /> The first semiconductor image sensor was the charge-coupled dlol, invented by [[Willard S. Boyle]] and [[George E. Smith]] at Bell Labs in 1969,<ref>{{Cite book | title = Scientific charge-coupled devices | author = James R. Janesick | publisher = SPIE Press | year = 2001 | isbn = 978-0-8194-3698-6 | pages = 3\u20134 | url = https://books.google.com/books?id=3GyE4SWytn4C&pg=PA3 }}</ref> based on [[MOS capacitor]] technology.<ref name="Williams" /> The [[NMOS logic|NMOS]] [[active-pixel sensor]] was later invented by [[Tsutomu Nakamura]]'s team at [[Olympus Corporation|Olympus]] in 1985,<ref>{{cite journal |last1=Matsumoto |first1=Kazuya |last2=Nakamura |first2=Tsutomu |last3=Yusa |first3=Atsushi |last4=Nagai |first4=Shohei |display-authors=1|date=1985 |title=A new MOS phototransistor operating in a non-destructive readout mode |journal=Japanese Journal of Applied Physics |volume=24 |issue=5A |page=L323|doi=10.1143/JJAP.24.L323 |bibcode=1985JaJAP..24L.323M }}</ref><ref name=fossum93>{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |title=Active pixel sensors: are CCDs dinosaurs? |journal=SPIE Proceedings Vol. 1900: Charge-Coupled Devices and Solid State Optical Sensors III |date=12 July 1993 |volume=1900 |doi=10.1117/12.148585 |publisher=International Society for Optics and Photonics |pages=2\u201314 |bibcode=1993SPIE.1900....2F |editor1-last=Blouke |editor1-first=Morley M.|citeseerx=10.1.1.408.6558 |s2cid=10556755 }}</ref><ref>{{cite document |last1=Fossum |first1=Eric R. |s2cid=18831792 |author1-link=Eric Fossum |title=Active Pixel Sensors |year=2007 }}</ref> which led to the development of the [[CMOS]] active-pixel sensor (CMOS sensor) by [[Eric Fossum]]'s team at the [[NASA]] [[Jet Propulsion Laboratory]] in 1993.<ref name="Fossum2014">{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |last2=Hondongwa |first2=D. B. |title=A Review of the Pinned Photodiode for CCD and CMOS Image Sensors |journal=IEEE Journal of the Electron Devices Society |date=2014 |volume=2 |issue=3 |pages=33\u201343 |doi=10.1109/JEDS.2014.2306412 |doi-access=free }}</ref><ref name=fossum93 />\n\nIn the 1960s, [[Eugene F. Lally]] of the Jet Propulsion Laboratory was thinking about how to use a mosaic photosensor to capture digital images. His idea was to take pictures of the planets and stars while travelling through space to give information about the astronauts' position.<ref name="Belbachir2009">{{cite book|author=Ahmed Nabil Belbachir|title=Smart Cameras|url=https://books.google.com/books?id=it5W3f7yqAgC&pg=PA8|date=20 October 2009|publisher=Springer Science & Business Media|isbn=978-1-4419-0953-4|pages=8\u2013}}</ref> As with [[Texas Instruments]] employee Willis Adcock's film-less camera (US patent 4,057,830) in 1972,<ref>{{cite web|url=https://patents.google.com/patent/US4057830A/en|title=Electronic photography system}}</ref> the technology had yet to catch up with the concept.\n\nThe [[Cromemco Cyclops]] was an all-digital camera introduced as a commercial product in 1975. Its design was published as a hobbyist construction project in the February 1975 issue of ''[[Popular Electronics]]'' magazine. It used a 32\u00d732 metal-oxide-semiconductor (MOS) image sensor, which was a modified MOS dynamic [[Random-access memory|RAM]] ([[Dynamic random-access memory|DRAM]]) [[memory chip]].<ref name="hackaday">{{cite web |last1=Benchoff|first1=Brian|title=Building the First Digital Camera|url=http://hackaday.com/2016/04/17/building-the-first-digital-camera/|website=[[Hackaday]]|access-date=30 April 2016|date=17 April 2016|quote=the Cyclops was the first digital camera}}</ref>\n\n[[Steven Sasson]], an engineer at [[Eastman Kodak]], invented and built a self-contained electronic camera that used a charge-coupled device (CCD) image sensor in 1975.<ref>{{cite book|first=David |last=Prakel|title=The Visual Dictionary of Photography|url=https://books.google.com/books?id=f7X5vYbUd0sC&pg=PA91|access-date=24 July 2013|date=10 December 2009|publisher=AVA Publishing|isbn=978-2-940411-04-7|page=91}}</ref><ref name=Dobbin>{{Cite web|last=DOBBIN|first=BEN|date=2005-09-09|title=Kodak engineer had revolutionary idea: the first digital camera|url=https://www.seattlepi.com/business/article/Kodak-engineer-had-revolutionary-idea-the-first-1182624.php|access-date=2021-12-29|website=seattlepi.com|language=en-US}}</ref><ref>{{cite news |last=Estrin |first=James |date=August 12, 2015 |title=Kodak's First Digital Moment |url=http://nyti.ms/1IK1u5a |newspaper=[[The New York Times]] |access-date=February 6, 2018}}</ref> Around the same time, [[Fujifilm]] began developing CCD technology in the 1970s.<ref name="Fujifilm">{{cite web |title=Innovation: FUJIX DS-1P: the world's first digital camera |website=[[Fujifilm]] |url=https://www.fujifilm.com/innovation/achievements/ds-1p/}}</ref> Early uses were mainly military and scientific; followed by medical and news applications.{{citation needed|date=February 2018}}\n\nPractical digital cameras were enabled by advances in [[data compression]], due to the impractically high [[computer memory|memory]] and [[bandwidth (computing)|bandwidth]] requirements of uncompressed images and video.<ref name="Belmudez">{{cite book |last1=Belmudez |first1=Benjamin |title=Audiovisual Quality Assessment and Prediction for Videotelephony |date=2014 |publisher=Springer |isbn=978-3-319-14166-4 |pages=11\u201313 |url=https://books.google.com/books?id=ULTzBQAAQBAJ&pg=PA13}}</ref> The most important compression algorithm is the [[discrete cosine transform]] (DCT),<ref name="Belmudez" /><ref name="Huang">{{cite book |last1=Huang |first1=Hsiang-Cheh |last2=Fang |first2=Wai-Chi |title=Intelligent Multimedia Data Hiding: New Directions |date=2007 |publisher=Springer |isbn=978-3-540-71169-8 |page=41 |url=https://books.google.com/books?id=67W5BQAAQBAJ&pg=PA41}}</ref> a [[lossy compression]] technique that was first proposed by [[N. Ahmed|Nasir Ahmed]] while he was working at the [[University of Texas]] in 1972.<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I Came Up With the Discrete Cosine Transform |journal=[[Digital Signal Processing (journal)|Digital Signal Processing]] |date=January 1991 |volume=1 |issue=1 |pages=4\u20135 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform}}</ref> Practical digital cameras were enabled by DCT-based compression standards, including the [[H.26x]] and [[MPEG]] [[video coding standards]] introduced from 1988 onwards,<ref name="Huang" /> and the [[JPEG]] [[image compression]] standard introduced in 1992.<ref>{{cite journal |last1=Hudson |first1=Graham |last2=L\u00e9ger |first2=Alain |last3=Niss |first3=Birger |last4=Sebesty\u00e9n |first4=Istv\u00e1n |last5=Vaaben |first5=J\u00f8rgen |title=JPEG-1 standard 25 years: past, present, and future reasons for a success |journal=Journal of Electronic Imaging |date=31 August 2018 |volume=27 |issue=4 |page=1 |doi=10.1117/1.JEI.27.4.040901|doi-access=free }}</ref><ref name="Atlantic">{{cite web |title=What Is a JPEG? The Invisible Object You See Every Day |url=https://www.theatlantic.com/technology/archive/2013/09/what-is-a-jpeg-the-invisible-object-you-see-every-day/279954/ |access-date=13 September 2019 |website=[[The Atlantic]] |date=24 September 2013}}</ref>\n\n[[Nikon]] was interested in digital photography since the mid-1980s. In 1986, while presenting to [[Photokina]], Nikon introduced an operational prototype of the first [[Digital single-lens reflex camera|SLR-type electronic camera]] (Still Video Camera), manufactured by [[Panasonic]].<ref name="busch">{{Cite book|last=Busch|first=David D.|url=https://books.google.com/books?id=jOVSzasqzQ4C&pg=PT11|title=Nikon D70 Digital Field Guide|date=2011-08-02|publisher=John Wiley & Sons|isbn=978-1-118-08023-8|language=en}}</ref> The Nikon SVC was built around a sensor 2/3 " charge-coupled device of 300,000 [[pixels]]. Storage media, a magnetic floppy disk inside the camera allows recording 25 or 50 B&W images, depending on the definition.<ref>{{Cite web|title=Nikon SLR-type digital cameras|url=http://apphotnum.free.fr/N2BE2.html|access-date=2021-12-29|website=apphotnum.free.fr}}</ref> In 1988, Nikon released the first commercial electronic single-lens reflex camera, the QV-1000C.<ref name="busch" />\n\nAt Photokina 1988, Fujifilm introduced the FUJIX DS-1P, the first fully digital camera, capable of saving data to a semiconductor [[memory card]]. The camera's memory card had a capacity of 2 MB of [[Static random-access memory|SRAM]] (static random-access memory), and could hold up to ten photographs. In 1989, Fujifilm released the FUJIX DS-X, the first fully digital camera to be commercially released.<ref name="Fujifilm" /> In 1996, [[Toshiba]]'s 40 MB flash memory card was adopted for several digital cameras.<ref>{{Cite web|title=Toshiba | Business to Business Integrated Solutions|url=https://www.toshiba.com/tai/|access-date=2021-12-29|website=www.toshiba.com}}</ref>\n\nThe first commercial [[camera phone]] was the [[Kyocera]] Visual Phone VP-210, released in Japan in May 1999.<ref name="computerworld">{{cite web |title=Camera phones: A look back and forward |url=https://www.computerworld.com/article/2473084/camera-phones--a-look-back-and-forward.html |website=[[Computerworld]] |date=11 May 2012 |access-date=15 September 2019}}</ref> It was called a "mobile videophone" at the time,<ref>{{cite news |title=First mobile videophone introduced |url=http://edition.cnn.com/TECH/ptech/9905/18/japan.phonetv/ |access-date=15 September 2019 |agency=[[CNN]] |date=May 18, 1999}}</ref> and had a 110,000-[[pixel]] [[front-facing camera]].<ref name="computerworld" /> It stored up to 20 JPEG [[digital images]], which could be sent over e-mail, or the phone could send up to two images per second over Japan's [[Personal Handy-phone System]] (PHS) [[cellular network]].<ref name="computerworld" /> The [[Samsung]] SCH-V200, released in [[South Korea]] in June 2000, was also one of the first phones with a built-in camera. It had a [[Thin-film transistor|TFT]] [[liquid-crystal display]] (LCD) and stored up to 20 [[digital photo]]s at 350,000-pixel resolution. However, it could not send the resulting image over the telephone function, but required a computer connection to access photos.<ref name="digitaltrends">{{cite web |title=From J-Phone to Lumia 1020: A complete history of the camera phone |url=https://www.digitaltrends.com/mobile/camera-phone-history/ |website=[[Digital Trends]] |date=August 11, 2013 |access-date=15 September 2019}}</ref> The first mass-market camera phone was the [[J-SH04]], a [[Sharp Corporation|Sharp]] [[J-Phone]] model sold in Japan in November 2000.<ref>{{cite web |url=http://www.hoista.net/post/18437919296/evolution-of-the-cameraphone-from-sharp-j-sh04-to |title=Evolution of the Camera phone: From Sharp J-SH04 to Nokia 808 Pureview |publisher=Hoista.net |date=2012-02-28 |access-date=2013-06-21 |url-status=live |archive-url=https://web.archive.org/web/20130731053246/http://www.hoista.net/post/18437919296/evolution-of-the-cameraphone-from-sharp-j-sh04-to |archive-date=2013-07-31 }}</ref><ref name="digitaltrends" /> It could instantly transmit pictures via cell phone telecommunication.<ref>{{cite news |title=Taking pictures with your phone |url=http://news.bbc.co.uk/1/hi/sci/tech/1550622.stm |access-date=15 September 2019 |work=[[BBC News]] |agency=[[BBC]] |date=18 September 2001}}</ref> By the mid-2000s, higher-end [[cell phones]] had an integrated digital camera. By the beginning of the 2010s, almost all [[smartphone]]s had an integrated digital camera."}},
{"article_title": "File Allocation Table", "pageid": "53045", "revid": "1062051454", "timestamp": "2021-12-25T23:10:55Z", "history_paths": [["File Allocation Table --- Introduction ---", "Types"]], "categories": ["1977 software", "computer file systems", "disk file systems", "dos technology", "ecma standards", "file systems supported by the linux kernel", "windows components", "windows disk file systems"], "heading_tree": {"File Allocation Table --- Introduction ---": {"Overview": {"Concepts": {}, "Uses": {}, "Nomenclature": {}}, "Types": {"Original 8-bit FAT": {}, "FAT12": {}, "Initial FAT16": {}, "Logical sectored FAT": {}, "Final FAT16": {}, "FAT32": {"Maximal sizes": {}, "Development": {}}}, "Extensions": {"Secured FAT  for single/multiuser security schemes including those by DRI and Linux": {}, "Compressed FAT  for compressed and encrypted FAT schemes": {}, "Deletion tracking  for MSX-DOS, SAVENAME, DELWATCH, SENTRY, UNDELETE, RECYCLE etc.": {}, "Large file support  for files larger than 2/4 GB, FAT+ etc.": {}, "Transaction-safe FAT  for TFAT and other transaction safe FAT variants -->": {}, "Extended attributes": {}, "Long file names": {}, "Forks and alternate data streams": {}, "UMSDOS permissions and filenames": {}, "FAT+": {}}, "Derivatives": {"Turbo FAT": {}, "FATX": {}, "exFAT": {}}, "Patents": {"Challenges and lawsuits": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"File Allocation Table --- Introduction ---|Types": "{{See also|Timeline of DOS operating systems}}\n\n <!-- NB. "FAT8" and "FAT10" are used as handy invisible anchors, but they never were the official names for these FAT variants, and therefore must not be used in the visible text. -->\n\n{{infobox file system\n| name = 8-bit FAT\n| full_name = 8-bit File Allocation Table\n| developer = [[Microsoft]], [[NCR Corporation|NCR]], [[Seattle Computer Products|SCP]]\n| variants = \n| introduction_date = 1977/1978: [[NCR Basic +6]] for NCR<br />1978: [[Standalone Disk BASIC-80]] (16-byte directory entries)<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /><br />(1978: [[Standalone Disk BASIC-86]] internal only)<br />1979-06-04: [[Standalone Disk BASIC-86]] for SCP (16-byte directory entries)<br />1979: [[MIDAS (operating system)|MIDAS]] (32-byte directory entries)\n| partition_id = \n| directory_struct = \n| file_struct = \n| bad_blocks_struct = \n| max_volume_size = <!-- TBD -->\n| max_file_size = 8 MB\n| max_files_no = <!-- TBD -->\n| max_filename_size = [[6.3 filename]]<!-- displayed with decimal dot as "123456.789" --> (binary files), 9 characters<!-- displayed with space as "123456 789" --> (ASCII files)<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" />\n| max_directory_depth = no sub-directories\n| dates_recorded = No\n| forks_streams = \n| attributes = Write protected, [[EBCDIC]] conversion, Read after write, Binary (random rather than sequential file)<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" />\n| file_system_permissions = \n| compression = \n| encryption = \n| data_deduplication = \n| OS = \n| filename_character_set = [[ASCII]] (<code>0x00</code> and <code>0xFF</code> not allowed in first character)<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /> <!-- In reality, character set is most probably more limited due to BASIC language restrictions. -->\n| file_size_granularity = record-granularity (128 bytes<!-- 256 bytes for mini-disks? -->)<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" />\n}}\nThe original FAT file system (or ''FAT structure'', as it was called initially) was designed and implemented by [[Marc McDonald]],<ref name="Duncan_1988_MS-DOS_Encyclopedia" /> based on a series of discussions between McDonald and [[Bill Gates]].<ref name="Duncan_1988_MS-DOS_Encyclopedia" />\nIt was introduced with [[8-bit]] table elements<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /><ref name="Duncan_1988_MS-DOS_Encyclopedia" /> (and valid data cluster numbers up to <code>0xBF</code><ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" />) in a precursor to [[Microsoft]]'s ''[[Standalone Disk BASIC-80]]'' for an [[Intel 8080|8080]]-based successor<ref group="nb" name="NB_NCR_FAT" /> of the [[NCR 7200 model VI]]<!-- model I and IV did not came with BASIC, whereas the still cassette-based model VI did in Q1/1977 --> data-entry terminal, equipped with 8-inch (200 mm) floppy disks, in 1977<ref name="Manes_1993_Gates" /> or 1978.<ref group="nb" name="NB_NCR_FAT" />\nIn 1978, ''Standalone Disk BASIC-80'' was ported to the [[Intel 8086|8086]] using an emulator on a DEC [[PDP-10]],<ref name="Hunter_1983_Softalk" /> since no real 8086 systems were available at this time.\nThe FAT file system was also used in Microsoft's [[MIDAS (operating system)|MDOS/MIDAS]],<ref name="Duncan_1988_MS-DOS_Encyclopedia" /> an operating system for 8080/Z80 platforms written by McDonald since 1979.\nThe ''Standalone Disk BASIC'' version supported three FATs,<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /><ref name="Schulman_1994_Undocumented-DOS" /> whereas this was a parameter for MIDAS. Reportedly, MIDAS was also prepared to support 10-bit, 12-bit and 16-bit FAT variants. While the size of directory entries was 16 bytes in ''Standalone Disk BASIC'',<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /> MIDAS instead occupied 32 bytes per entry.\n\n[[Tim Paterson]] of [[Seattle Computer Products]] (SCP) was first introduced to Microsoft's FAT structure when he helped [[Bob O'Rear]] adapting the ''[[Standalone Disk BASIC-86]]'' emulator port onto SCP's [[S-100 bus]] 8086 CPU board prototype during a guest week at Microsoft in May 1979.<ref name="Hunter_1983_Softalk" /> The final product was shown at [[Lifeboat Associates]]' booth stand at the [[National Computer Conference]] in New York<ref name="Hunter_1983_Softalk" /> on June 4\u20137, 1979, where Paterson learned about the more sophisticated FAT implementation in MDOS/MIDAS<ref name="Duncan_1988_MS-DOS_Encyclopedia" /> and McDonald talked to him about the design of the file system.<ref name="Manes_1993_Gates" />\n\n <!-- NB. The header "FAT12" is used in redirects to this page. -->\n\n{{infobox file system\n| name                    = FAT12\n| developer               = [[Seattle Computer Products|SCP]], [[Microsoft]], [[IBM]], [[Digital Research]], [[Novell]]\n| full_name               = [[Design of the FAT file system#FAT12|12-bit File Allocation Table]]\n| introduction_date       = 1980-07 ([[QDOS 0.10]], 16-byte directory entries)<br />1981-02-25 ([[86-DOS 0.42]], 32-byte [[FAT directory entry|directory entries]], several reserved sectors)<br />c. 1981\u201308/10 ([[PC DOS 1.0]], 32-byte directory entries, 1 reserved sector)<br />1982-03-03 ([[MS-DOS 1.25]], 32-byte directory entries, 1 reserved sector)\n| partition_id            = [[Master Boot Record|MBR]]/[[Extended Boot Record|EBR]]:<br />[[#FAT12|FAT12]]: <code>{{abbr|0x|Values in C-notation for hexadecimal numbers}}[[Partition type#PID 01h|01]]</code> e.a.<br />[[Basic data partition|BDP]]:<br /><code>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</code>\n| max_volume_size         = 16 MB (with 4 KB clusters)<br />32 MB (with 8 KB clusters)<!-- larger volumes should use logical sectored FAT partition IDs or FAT16 partition IDs -->\n| max_file_size           = limited by volume size\n| file_size_granularity   = 1 byte\n| max_files_no            = 4,068 for 8 KB clusters<!-- 2^12 - 12 (reserved clusters) - 16 (number of 8 KB clusters for directory entries) -->\n| max_filename_size       = [[8.3 filename]] with [[OEM character set|OEM]] characters,<br />255 [[UCS-2]] characters<ref group="nb" name="NB_LFN_UNI"/> when using [[Long filename|LFN]]\n| max_directory_depth     = 32 levels or 66 characters (with [[Current Directory Structure|CDS]]),<br />60 levels or more (without CDS)\n| dates_recorded          = Modified date (not with 86-DOS before 0.42), modified time (not with PC DOS 1.0 and 86-DOS), creation date/time (DOS 7.0 and higher only), access date (only available with [[ACCDATE (CONFIG.SYS directive)|ACCDATE]] enabled),<ref name="Microsoft_2006_ACCDATE" /> deletion date/time (only with DELWATCH 2<!-- with Novell DOS 7, Caldera OpenDOS 7.01, DR-DOS 7.02 and higher -->)\n| date_range              = [[Epoch of 1980-01-01|1980-01-01]] to [[Year 2100 problem|2099-12-31]] ([[Year 2108 problem|2107-12-31]])\n| date_resolution         = 2 seconds for last modified time,<br />10 ms for creation time,<br />1 day for access date,<br />2 seconds for deletion time\n| attributes              = [[FAT file attributes|Read-only]] (since DOS 2.0), [[FAT file attributes|Hidden]], [[FAT file attributes|System]], [[FAT file attributes|Volume]] (since [[MS-DOS 1.28]] and [[PC DOS 2.0]]), [[FAT file attributes|Directory]] (since [[MS-DOS 1.40]] and PC DOS 2.0), [[FAT file attributes|Archive]] (since DOS 2.0)\n| file_system_permissions = File, directory and volume access rights for [[FAT file access rights|Read]], [[FAT file access rights|Write]], [[FAT file access rights|Execute]], [[FAT file access rights|Delete]] only with [[DR-DOS]], [[PalmDOS]], [[Novell DOS]], [[OpenDOS]], [[FlexOS]], [[IBM 4680 OS|4680 OS]], [[IBM 4690 OS|4690 OS]], [[Concurrent DOS]], [[Multiuser DOS]], [[Datapac System Manager|System Manager]], [[REAL/32]] (Execute right only with FlexOS, 4680 OS, 4690 OS; individual file / directory passwords not with FlexOS, 4680 OS, 4690 OS<!-- at least I could not find any user or programmer's documentation for it so far -->; [[FAT file access rights|World]]/[[FAT file access rights|Group]]/[[FAT file access rights|Owner]] permission classes only with multiuser security loaded)\n| compression             = Per-volume, [[SuperStor]], [[Stacker (disk compression)|Stacker]], [[DoubleSpace]], [[DriveSpace]]\n| encryption              = Per-volume only with [[DR-DOS]]\n}}\nBetween April and August 1980, while borrowing the FAT concept for SCP's own 8086 operating system [[QDOS 0.10]],<ref name="Hunter_1983_Softalk" /> Tim Paterson extended the table elements to '''12 bits''',<ref name="Paterson_2007_Design-DOS" /> reduced the number of FATs to two, redefined the semantics of some of the reserved cluster values, and modified the disk layout, so that the root directory was now located between the FAT and the data area for his implementation of '''FAT12'''. Paterson also increased the nine-character (6.3) filename<ref name="Microsoft_1979_BASIC80-50" /><ref name="Microsoft_1979_BASIC80-51" /> length limit to eleven characters to support [[CP/M]]-style [[8.3 filename]]s and [[File Control Block]]s. The format used in Microsoft ''Standalone Disk BASIC's'' 8-bit file system precursor was not supported by QDOS. By August 1980, QDOS had been renamed [[86-DOS]].<ref name="BYTE_1980_86-DOS" /> Starting with [[86-DOS 0.42]], the size and layout of directory entries was changed from 16 bytes to 32 bytes<ref name="SCP_1981_86-DOS_1.0_Addendum" /> in order to add a file date stamp<ref name="SCP_1981_86-DOS_1.0_Addendum" /> and increase the theoretical file size limit beyond the previous limit of 16 MB.<ref name="SCP_1981_86-DOS_1.0_Addendum" />\n[[86-DOS 1.00]] became available in early 1981. Later in 1981, 86-DOS evolved into Microsoft's [[MS-DOS]] and [[IBM]] [[PC DOS]].<ref name="Duncan_1988_MS-DOS_Encyclopedia" /><ref name="Paterson_2007_Design-DOS" /><ref name="Wallace_1992_Harddrive" />\nThe capability to read previously formatted volumes with 16-byte directory entries<ref name="SCP_1981_86-DOS_1.0_Addendum" /> was dropped with [[MS-DOS 1.20]].\n\nFAT12 used 12-bit entries for the cluster addresses; some values were reserved to mark the end of a chain of clusters, to mark unusable areas of the disk, or for other purposes, so the maximum number of clusters was limited to  4078.<ref name="Norton2" /><ref name="Jenkinson_2000_Forensic" /> To conserve disk space, two 12-bit FAT entries used three consecutive 8-bit bytes on disk, requiring manipulation to unpack the 12-bit values.  This was sufficient for the original floppy disk drives, and small hard disk up to 32 megabytes. The [[#FAT16B|FAT16B]]  version available with DOS 3.31, supported [[32-bit]] sector numbers and so increased the  volume size limit.\n\nAll the control structures fit inside the first track, to avoid head movement during read and write operations. Any bad sector in the control structures area would make the disk unusable.  The DOS formatting tool rejected such disks completely. Bad sectors were allowed only in the file data area. Clusters containing bad sectors were marked unusable with the reserved value <code>0xFF7</code>.\n\nWhile 86-DOS supported three disk formats (250.25 KB, 616 KB and 1232 KB with [[FAT ID]]s <code>0xFF</code> and <code>0xFE</code> on 8-inch (200 mm) floppy drives, IBM [[PC DOS 1.0]], released with the original [[IBM Personal Computer]] in 1981, supported only an 8-sector floppy format with a formatted capacity of 160 KB (FAT ID <code>0xFE</code>) for single-sided 5.25-inch floppy drives, and [[PC DOS 1.1]] added support for a [[double-sided disk|double-sided]] format with 320 KB (FAT ID <code>0xFF</code>). [[PC DOS 2.0]] introduced support for 9-sector floppy formats with 180 KB (FAT ID <code>0xFC</code>) and 360 KB (FAT ID <code>0xFD</code>).\n\n86-DOS 1.00 and PC DOS 1.0 directory entries included only one date, the last modified date. PC DOS 1.1 added the last modified time. PC DOS 1.x [[file attribute]]s included a hidden bit and system bit, with the remaining six bits undefined. At this time, DOS did not support sub-directories, but typically there were only a few dozen files on a diskette. \n\nThe [[PC XT]] was the first PC with a hard drive from IBM, and PC DOS 2.0 supported that hard drive with FAT12 ([[FAT ID]] <code>0xF8</code>). The fixed assumption of 8 sectors per clusters on hard disks practically limited the maximum partition size to 16 MB for 512 byte sectors and 4 KB clusters.\n\nThe ''[[BIOS Parameter Block]]'' (''BPB'') was introduced with PC DOS 2.0 as well, and this version also added read-only, [[archive bit|archive]], [[volume (computing)|volume label]], and [[Directory (file systems)|directory]] attribute bits for hierarchical sub-directories.<ref name="two" />\n\n[[MS-DOS 3.0]] introduced support for high-density 1.2 MB 5.25-inch diskettes (media descriptor <code>0xF9</code>), which notably had 15 sectors per track, hence more space for the FATs.\n\nFAT12 remains in use on all common [[floppy disks]], including 1.44 MB and later 2.88 MB disks (media descriptor byte <code>0xF0</code>).\n\n \n{{infobox file system\n| name                    = FAT16.\n| developer               = [[Microsoft]], [[IBM]], [[Digital Research]], [[Novell]]\n| full_name               = [[Design of the FAT file system#FAT16|16-bit File Allocation Table]]<br />(with 16-bit sector entries)\n| introduction_date       = 1984-08-14 (PC DOS 3.0)<br />1984-08 (MS-DOS 3.0)\n| partition_id            = [[Master Boot Record|MBR]]/[[Extended Boot Record|EBR]]:<br />[[#FAT16|FAT16]]: <code>{{abbr|0x|Values in C-notation for hexadecimal numbers}}[[Partition type#PID_04h|04]]</code> e.a.<br />[[Basic data partition|BDP]]: <code>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</code>\n<!-- needs more refinement as this is version dependent:\n| max_volume_size         = 16 [[Megabyte|MB]] (with 2 KB clusters) --><!-- larger volumes should use logical sectored FAT partition IDs or FAT16B partition ID -->\n| max_file_size           = limited by volume size\n| file_size_granularity   = 1 byte\n| max_files_no            = 65,536 for 32 KB clusters<!-- 2^16 - 12 (reserved clusters) - 64 (number of 32 KB clusters for directory entries) -->\n| max_filename_size       = [[8.3 filename]] with [[OEM character set|OEM]] characters,<br />255 [[UCS-2]] characters<ref group="nb" name="NB_LFN_UNI"/> when using [[Long filename|LFN]]\n| max_directory_depth     = 32 levels or 66 characters (with [[Current Directory Structure|CDS]]),<br />60 levels or more (without CDS)\n| dates_recorded          = Modified date/time, creation date/time (DOS 7.0 and higher only), access date (only available with [[ACCDATE (CONFIG.SYS directive)|ACCDATE]] enabled),<ref name="Microsoft_2006_ACCDATE" /> deletion date/time (only with DELWATCH 2<!-- with Novell DOS 7, Caldera OpenDOS 7.01, DR-DOS 7.02 and higher -->)\n| date_range              = [[Epoch of 1980-01-01|1980-01-01]] to [[Year 2100 problem|2099-12-31]] ([[Year 2108 problem|2107-12-31]])\n| date_resolution         = 2 seconds for last modified time,<br />10 ms for creation time,<br />1 day for access date,<br />2 seconds for deletion time\n| attributes              = [[FAT file attributes|Read-only]], [[FAT file attributes|Hidden]], [[FAT file attributes|System]], [[FAT file attributes|Volume]], [[FAT file attributes|Directory]], [[FAT file attributes|Archive]]\n| file_system_permissions = File, directory and volume access rights for [[FAT file access rights|Read]], [[FAT file access rights|Write]], [[FAT file access rights|Execute]], [[FAT file access rights|Delete]] only with [[DR-DOS]], [[PalmDOS]], [[Novell DOS]], [[OpenDOS]], [[FlexOS]], [[IBM 4680 OS|4680 OS]], [[IBM 4690 OS|4690 OS]], [[Concurrent DOS]], [[Multiuser DOS]], [[Datapac System Manager|System Manager]], [[REAL/32]] (Execute right only with FlexOS, 4680 OS, 4690 OS; individual file / directory passwords not with FlexOS, 4680 OS, 4690 OS<!-- at least I could not find any user or programmer's documentation for it so far -->; [[FAT file access rights|World]]/[[FAT file access rights|Group]]/[[FAT file access rights|Owner]] permission classes only with multiuser security loaded)\n| compression             = Per-volume, [[SuperStor]], [[Stacker (disk compression)|Stacker]], [[DoubleSpace]], [[DriveSpace]]\n| encryption              = Per-volume only with [[DR-DOS]]\n}}\nIn 1984, IBM released the [[PC AT]], which  required PC DOS 3.0 to access its 20 MB hard disk. <ref name="IBM_1984_PCDOS30" /><ref name="IBM_1985_Reference" /> Microsoft introduced MS-DOS 3.0 in parallel. Cluster addresses were increased to 16-bit, allowing for up to 65,526 clusters per volume. However, the maximum possible number of sectors and the maximum [[Disk partitioning|partition]] size of 32 MB did not change. Although cluster addresses were 16 bits, this format was not what today is commonly understood as '''FAT16'''.\nA [[partition type]] <code>[[Partition type#PID_04h|0x04]]</code> indicates this form of FAT16 with less than 65536 sectors (less than 32 MB for sector size 512). The benefit of FAT16 was the use of smaller clusters, making disk usage more efficient, particularly for large numbers of files only a few hundred bytes in size.\n\nAs MS-DOS 3.0 formatted all 16 MB-32 MB partitions in the FAT16 format, a 20 MB hard disk formatted under MS-DOS 3.0 was not accessible by MS-DOS 2.0. <ref name="Microsoft_69912" /> MS-DOS 3.0 to MS-DOS 3.30 could still access FAT12 partitions under 15 MB, but required all 16 MB-32 MB partitions to be FAT16, and so could not access MS-DOS 2.0 partitions in this size range. MS-DOS 3.31 and higher could access 16 MB-32 MB FAT12 partitions again.\n\n <!-- NB. The header "Logical sectored FAT" is used in redirects to this page. -->\n\nMS-DOS and PC DOS implementations of FAT12 and FAT16 could not access disk partitions larger than 32 megabytes. Several manufacturers developed their own FAT variants within their OEM versions of MS-DOS.<ref name="Novell_1993_FYI.M.1101"/>\n\nSome vendors ([[AST Research|AST]] and [[NEC]]<ref name="Novell_1993_FYI.M.1101"/>) supported [[AST MBR<!-- NEC MBR -->|eight]], instead of the standard [[Partition table (master boot record)|four]], primary partition entries in their custom extended ''[[Master Boot Record]]'' (''MBR''), and they adapted MS-DOS to use more than a single primary partition.\n\nOther vendors worked around the volume size limits imposed by the 16-bit sector entries by increasing the apparent ''size'' of the sectors the file system operated on. These ''logical sectors'' were larger (up to 8192 bytes) than the ''physical sector'' size (still 512 bytes) on the disk. The DOS-BIOS or System BIOS would then combine multiple physical sectors into logical sectors for the file system to work with.\n\nThese changes were transparent to the file system implementation in the DOS kernel. The underlying DOS-BIOS translated these logical sectors into physical sectors according to partitioning information and the drive's physical geometry.\n\nThe drawback of this approach was increased memory used for sector buffering and deblocking. Since older DOS versions could not use large logical sectors, the OEMs introduced new partition IDs for their FAT variants in order to hide them from off-the-shelf issues of MS-DOS and PC DOS. Known partition IDs for logical sectored FATs include: <code>[[Partition type#PID_08h|0x08]]</code> ([[Commodore International|Commodore]] MS-DOS 3.x), <code>[[Partition type#PID_11h|0x11]]</code> ([[Leading Edge Hardware Products|Leading Edge]] MS-DOS 3.x), <code>[[Partition type#PID_14h|0x14]]</code> (AST MS-DOS 3.x), <code>[[Partition type#PID_24h|0x24]]</code> (NEC MS-DOS 3.30<ref name="Novell_1993_FYI.M.1101"/>), <code>[[Partition type#PID_56h|0x56]]</code> ([[AT&T Corporation|AT&T]] MS-DOS 3.x), <code>[[Partition type#PID_E5h|0xE5]]</code> ([[Tandy Computers|Tandy]] MS-DOS), <code>[[Partition type#PID_F2h|0xF2]]</code> ([[Sperry Corporation|Sperry IT]] MS-DOS 3.x, [[Unisys]] MS-DOS 3.3 \u2013 also used by [[Digital Research]] [[DOS Plus]] 2.1).<ref name="Brouwer_2002_Partition-IDs" /> OEM versions like Toshiba MS-DOS, Wyse MS-DOS 3.2<!-- with 1024 bytes/sector --> and 3.3,<ref name="Microsoft_2000_Wyse-DOS" /> as well as Zenith MS-DOS are also known to have utilized logical sectoring.<ref name="Microsoft_2000_Logical-sectoring" /><!-- but partition IDs and other specifics of these formats are not known -->\n\nWhile non-standard and sub-optimal, these FAT variants are perfectly valid according to the specifications of the file system itself. Therefore, even if default issues of MS-DOS and PC DOS were not able to cope with them, most of these vendor-specific FAT12 and FAT16 variants can be mounted by more flexible file system implementations in operating systems such as DR-DOS, simply by changing the partition ID to one of the recognized types.<ref group="nb" name="NB_DRDOS_Logical-Sectoring" /> Also, if they no longer need to be recognized by their original operating systems, existing partitions can be "converted" into FAT12 and FAT16 volumes more compliant with versions of MS-DOS/PC DOS 4.0\u20136.3, which do not support sector sizes different from 512 bytes,<ref name="Brouwer_2002_Logical_FAT" /> by switching to a [[DOS 3.31 BPB|BPB with 32-bit entry]] for the number of sectors, as introduced since DOS 3.31 (see [[#FAT16B|FAT16B]] below), keeping the cluster size and reducing the [[BPB logical sector size|logical sector size in the BPB]] down to 512 bytes, while at the same time increasing the counts of logical sectors per cluster, reserved logical sectors, total logical sectors, and logical sectors per FAT by the same factor.\n\nA parallel development in MS-DOS / PC DOS which allowed an increase in the maximum possible FAT size was the introduction of multiple FAT partitions on a hard disk. To allow the use of more FAT partitions in a compatible way, a new partition type was introduced in PC DOS 3.2 (1986), the ''[[Extended boot record|extended partition]]'' (EBR),<ref name="Duncan_1988_MS-DOS_Encyclopedia" /> which is a container for an additional partition called ''logical drive''. Since PC DOS 3.3 (April 1987), there is another, optional extended partition containing the next ''logical drive'', and so on. The [[Master Boot Record|MBR]] of a hard disk can either define up to four primary partitions, or an extended partition in addition to up to three primary partitions.\n\n{{See also|Extended boot record}}\n\n \n{{infobox file system\n| name                    = FAT16B\n| developer               = [[Compaq]], [[Digital Research]], [[IBM]], [[Microsoft]], [[Novell]]\n| full_name               = [[Design of the FAT file system#FAT16|16-bit File Allocation Table]]<br />(with 32-bit sector entries)\n| introduction_date       = 1987-11 ([[Compaq MS-DOS 3.31]])<br />1988-06-28 ([[DR DOS 3.31]])<br />1988 ([[IBM DOS 4.0]])<br />1988 ([[OS/2 1.1]])<br />1988 ([[MS-DOS 4.0 (IBM-developed)|MS-DOS 4.0]])\n| partition_id            = [[Master Boot Record|MBR]]/[[Extended Boot Record|EBR]]:<br />[[#FAT16B|FAT16B]]: <code>{{abbr|0x|Values in C-notation for hexadecimal numbers}}[[Partition type#PID_06h|06]]</code><code>[[Partition type#PID_0Eh|0x0E]]</code>([[Logical block addressing|LBA]]),e.a.<br />[[Basic data partition|BDP]]:<br /><code>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</code>\n| min_volume_size         = 8 [[Megabyte|MB]] (with 128 byte sectors)<br />32 MB (with [[512e|512]] byte sectors)<br />256 MB (with [[4Kn|4 KB]] sectors)\n| max_volume_size         = 2 [[Gigabyte|GB]] (with 32 [[Kilobyte|KB]] clusters)<br />4 GB (with 64 KB clusters) (NT 4, PTS-DOS, EDR-DOS)<br />8 GB (with 128 KB clusters and <!-- 128 s/c -->1 or <!-- 64 s/c -->2 KB sectors) (NT 4 and EDR-DOS only)<br />8 GB (with 128 KB clusters and <!-- 256 s/c -->512 byte sectors) (EDR-DOS only)<br />16 GB (with 256 KB clusters and <!-- 128 s/c -->2 or <!-- 64 s/c -->4 KB sectors) (NT 4 only)\n| max_file_size           = 2,147,483,647 bytes (2 GB \u2013 1)<!-- 2^31 - 1 --> (without [[large file support|LFS]])<br />4,294,967,295 bytes (4 GB \u2013 1)<!-- 2^32 - 1 --> (with [[large file support|LFS]])<br />limited by volume size only (with FAT16+<ref name="DRDOS_FAT+_R2" />)\n| file_size_granularity   = 1 byte\n| max_files_no            = 65,460 for 32 KB clusters<!-- 2^16 - 12 (reserved clusters) - 64 (number of 32 KB clusters for directory entries) -->\n| max_filename_size       = [[8.3 filename]] with [[OEM character set|OEM]] characters,<br />255 [[UCS-2]] characters<ref group="nb" name="NB_LFN_UNI"/> when using [[Long filename|LFN]]\n| max_directory_depth     = 32 levels or 66 characters (with [[Current Directory Structure|CDS]]),<br />60 levels or more (without CDS)\n| dates_recorded          = Modified date/time, creation date/time (DOS 7.0 and higher only), access date (only available with [[ACCDATE (CONFIG.SYS directive)|ACCDATE]] enabled),<ref name="Microsoft_2006_ACCDATE" /> deletion date/time (only with DELWATCH 2<!-- with Novell DOS 7, Caldera OpenDOS 7.01, DR-DOS 7.02 and higher -->)\n| date_range              = [[Epoch of 1980-01-01|1980-01-01]] to [[Year 2100 problem|2099-12-31]] ([[Year 2108 problem|2107-12-31]])\n| date_resolution         = 2 seconds for last modified time,<br />10 ms for creation time,<br />1 day for access date,<br />2 seconds for deletion time\n| attributes              = [[FAT file attributes|Read-only]], [[FAT file attributes|Hidden]], [[FAT file attributes|System]], [[FAT file attributes|Volume]], [[FAT file attributes|Directory]], [[FAT file attributes|Archive]]\n| file_system_permissions = File, directory and volume access rights for [[FAT file access rights|Read]], [[FAT file access rights|Write]], [[FAT file access rights|Execute]], [[FAT file access rights|Delete]] only with [[DR-DOS]], [[PalmDOS]], [[Novell DOS]], [[OpenDOS]], [[FlexOS]], [[IBM 4680 OS|4680 OS]], [[IBM 4690 OS|4690 OS]], [[Concurrent DOS]], [[Multiuser DOS]], [[Datapac System Manager|System Manager]], [[REAL/32]] (Execute right only with FlexOS, 4680 OS, 4690 OS; individual file / directory passwords not with FlexOS, 4680 OS, 4690 OS<!-- at least I could not find any user or programmer's documentation for it so far -->; [[FAT file access rights|World]]/[[FAT file access rights|Group]]/[[FAT file access rights|Owner]] permission classes only with multiuser security loaded)\n| compression             = Per-volume, [[SuperStor]], [[Stacker (disk compression)|Stacker]], [[DoubleSpace]], [[DriveSpace]]\n| encryption              = Per-volume only with [[DR-DOS]]\n}}\nIn November 1987, [[Compaq MS-DOS 3.31|Compaq Personal Computer DOS 3.31]] (a modified OEM version of MS-DOS 3.3 released by Compaq with their machines) introduced what today is simply known as ''the FAT16'' format, with the expansion of the 16-bit disk sector count to 32 bits in the BPB.\nAlthough the on-disk changes were minor, the entire DOS disk driver had to be converted to use 32-bit sector numbers, a task complicated by the fact that it was written in 16-bit [[x86 assembly language|assembly language]].\nThe result was initially called the ''DOS 3.31 Large File System''. [[Microsoft]]'s <code>[[DSKPROBE]]</code> tool refers to type <code>[[Partition type#PID_06h|0x06]]</code> as ''BigFAT'',<ref name="Microsoft_2003_CC736327" /> whereas some older versions of <code>[[FDISK]]</code> described it as ''BIGDOS''. Technically, it is known as '''FAT16B'''.\n\nSince older versions of DOS were not designed to cope with more than 65535 sectors, it was necessary to introduce a new partition type for this format in order to hide it from pre-3.31 issues of DOS. The original form of FAT16 (with less than 65536 sectors) had a [[partition type]] <code>[[Partition type#PID_04h|0x04]]</code>. To deal with disks larger than this, type <code>[[Partition type#PID_06h|0x06]]</code> was introduced to indicate 65536 or more sectors. In addition to this, the disk driver was expanded to cope with more than 65535 sectors as well. The only other difference between the original FAT16 and the newer FAT16B format is the usage of a [[DOS 3.31 BPB|newer BPB]] format with 32-bit sector entry. Therefore, newer operating systems supporting the FAT16B format can cope also with the original FAT16 format without any necessary changes.\n\nIf partitions to be used by pre-DOS 3.31 issues of DOS need to be created by modern tools, the only criteria theoretically necessary to meet are a sector count of less than 65536, and the usage of the old partition ID (<code>[[Partition type#PID_04h|0x04]]</code>). In practice however, type <code>[[Partition type#PID_01h|0x01]]</code> and <code>[[Partition type#PID_04h|0x04]]</code> primary partitions should not be physically located outside the first 32 MB of the disk, due to other restrictions in MS-DOS 2.x, which could not cope with them otherwise.\n\nIn 1988, the FAT16B improvement became more generally available through [[DR DOS]] 3.31, PC DOS 4.0, [[OS/2]] 1.1, and MS-DOS 4.0. The limit on partition size was dictated by the 8-bit [[Signedness|signed]] count of sectors per cluster, which originally had a maximum power-of-two value of 64. With the standard hard disk sector size of 512 bytes, this gives a maximum of 32 KB cluster size, thereby fixing the "definitive" limit for the FAT16 partition size at 2 GB for sector size 512. On [[magneto-optical]] media, which can have 1 or 2 KB sectors instead of 0.5 KB, this size limit is proportionally larger.\n\nMuch later, [[Windows NT]] increased the maximum cluster size to 64 KB, by considering the sectors-per-cluster count as unsigned. However, the resulting format was not compatible with any other FAT implementation of the time, and it generated greater [[internal fragmentation]]. [[Windows 98]], SE and ME also supported reading and writing this variant, but its disk utilities did not work with it and some [[File control block|FCB]] services are not available for such volumes. This contributes to a confusing compatibility situation.\n\nPrior to 1995, versions of DOS accessed the disk via [[Cylinder-head-sector|CHS]] addressing only. When [[Windows 95]](MS-DOS 7.0) introduced [[Logical block addressing|LBA]] disk access, partitions could start being physically located outside the first c. 8 GB<!-- exact value is somewhat smaller --> of this disk and thereby out of the reach of the traditional CHS addressing scheme. Partitions partially or fully located beyond the CHS barrier therefore had to be hidden from non-LBA-enabled operating systems by using the new partition type <code>[[Partition type#PID_0Eh|0x0E]]</code> in the partition table instead. FAT16 partitions using this partition type are also named '''FAT16X'''.<ref name="Microsoft_2004_KB120138" /> The only difference, compared to previous FAT16 partitions, is the fact that some CHS-related geometry entries in the BPB record, namely the number of sectors per track and the number of heads, may contain no or misleading values and should not be used.\n\nThe number of root directory entries available for FAT12 and FAT16 is determined when the volume is formatted, and is stored in a 16-bit field. For a given number <code>RDE</code> and sector size <code>SS</code>, the number <code>RDS</code> of root directory sectors is <code>RDS = ceil((RDE \u00d7 32) / SS)</code>, and <code>RDE</code> is normally chosen to fill these sectors, i.e., <code>RDE \u00d7 32 = RDS \u00d7 SS</code>. FAT12 and FAT16 media typically use 512 root directory entries on non-floppy media. Some third-party tools, like [[mkdosfs]], allow the user to set this parameter.<ref name="MKDOSFS" />\n\n {{Infobox file system\n| name                    = FAT32\n| full_name             DEVICE1\n\n[[Design of the FAT file system#FAT32|32-bit File Allocation Table]]<br />(with 28-bit cluster entries)\n| developer               = [[Microsoft]], [[Caldera UK|Caldera]]\n| variants = \n| introduction_date       = August 1996 ([[Windows 95 OSR2]])\n| partition_id            = [[Master Boot Record|MBR]]/[[Extended Boot Record|EBR]]:<br />[[#FAT32|FAT32]]: <code>{{abbr|0x|Values in C-notation for hexadecimal numbers}}[[Partition type#PID_0Bh|0B]]</code><code>[[Partition type#PID_0Ch|0x0C]]</code>([[Logical block addressing|LBA]]),e.a.<br />[[Basic data partition|BDP]]:<br /><code>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</code>\n| directory_struct = \n| file_struct = \n| bad_blocks_struct = \n| min_volume_size         = 32 [[Megabyte|MB]]-4.5 [[Kilobyte|KB]] (with 65525 clusters and 512 byte sectors)<br />256 MB-36 KB (with 65525 clusters and 4 [[Kilobyte|KB]] sectors)\n| max_volume_size         = 2 [[Terabyte|TB]] (with 512 byte sectors)<br />8 TB (with 2 KB sectors and 32 KB clusters)<br />16 TB (with 4 KB sectors and 64 KB clusters)\n| max_file_size           = 2,147,483,647 bytes (2 GB \u2013 1)<!-- 2^31 - 1 --> (without [[large file support|LFS]])<br />4,294,967,295 bytes (4 GB \u2013 1)<!-- 2^32 - 1 --><ref name="GB4" /> (with [[large file support|LFS]])<br />274,877,906,943 bytes (256 GB \u2013 1)<!-- 2^38 -1 --> (only with FAT32+<ref name="DRDOS_FAT+_R2" />)\n| max_files_no            = 268,173,300 for 32 KB clusters<!-- 2^28 - 12 (reserved clusters) - 262144 (number of 32 KB clusters for directory entries) -->\n| max_filename_size       = [[8.3 filename]] with [[OEM character set|OEM]] characters,<br />255 [[UCS-2]] characters<ref group="nb" name="NB_LFN_UNI"/> when using [[Long filename|LFN]]\n| max_directory_depth     = 32 levels or 66 characters (with [[Current Directory Structure|CDS]]),<br />60 levels or more (without CDS)\n| dates_recorded          = Modified date/time, creation date/time (DOS 7.0 and higher only), access date (only available with [[ACCDATE (CONFIG.SYS directive)|ACCDATE]] enabled),<ref name="Microsoft_2006_ACCDATE" /> deletion date/time (only with DELWATCH 2<!-- with Novell DOS 7, Caldera OpenDOS 7.01, DR-DOS 7.02 and higher -->)\n| date_range              = [[Epoch of 1980-01-01|1980-01-01]] to [[Year 2100 problem|2099-12-31]] ([[Year 2108 problem|2107-12-31]])\n| date_resolution         = 2 seconds for last modified time,<br />10 ms for creation time,<br />1 day for access date,<br />2 seconds for deletion time\n| forks_streams = \n| attributes              = [[FAT file attributes|Read-only]], [[FAT file attributes|Hidden]], [[FAT file attributes|System]], [[FAT file attributes|Volume]], [[FAT file attributes|Directory]], [[FAT file attributes|Archive]]\n| file_system_permissions = Partial, only with [[DR-DOS]], [[REAL/32]] and [[4690 OS]]\n| compression             = yes\n| encryption              = \n| data_deduplication = \n| OS = \n| file_size_granularity   = 16 byte\n}}\n\nIn order to overcome the volume size limit of FAT16, while at the same time allowing DOS [[Real mode|real-mode]] code to handle the format, Microsoft designed a new version of the file system, '''FAT32''', which supported an increased number of possible clusters, but could reuse most of the existing code, so that the [[conventional memory]] footprint was increased by less than 5 KB under DOS.<ref name="Microsoft_1998_CC768180" /> Cluster values are represented by [[32-bit]] numbers, of which 28 bits are used to hold the cluster number.\n\n The FAT32 boot sector uses a 32-bit field for the sector count, limiting the maximal FAT32 volume size to 2 [[terabyte]]s with a sector size of 512 [[byte]]s. The maximum FAT32 volume size is 16 TB with a sector size of 4,096 bytes.<ref name="Microsoft_2007_KB184006" /><ref name="Microsoft_2007_KB314463" /> The built-in [[Windows shell]] disk format tool on Microsoft Windows only supports volume sizes up to 32 GB, but larger FAT32 volumes can be created with the [[command prompt]], [[PowerShell]] or third-party tools and read by Microsoft Windows.<ref>{{Cite web |last=Glenn |first=Walter |title=How to Format USB Drives Larger Than 32GB With FAT32 on Windows |url=https://www.howtogeek.com/316977/how-to-format-usb-drives-larger-than-32gb-with-fat32-on-windows/ |access-date=2021-01-26 |website=How-To Geek |language=en-US}}</ref>\n\nThe maximal possible size for a file on a FAT32 volume is 4 [[gigabyte|GB]] minus 1 byte, or 4,294,967,295 (2<sup>32</sup> \u2212 1) bytes. This limit is a consequence of the 4-byte file length entry in the directory table and would also affect relatively huge FAT16 partitions enabled by a sufficient sector size. \n\nLike FAT12 and FAT16, FAT32 does not include direct built-in support for long filenames, but FAT32 volumes can optionally hold [[#VFAT|VFAT]] long filenames in addition to short filenames in exactly the same way as VFAT long filenames have been optionally implemented for FAT12 and FAT16 volumes.\n\n FAT32 was introduced with Windows 95 OSR2(MS-DOS 7.1) in 1996, although reformatting was needed to use it, and [[DriveSpace 3]] (the version that came with Windows 95 OSR2 and Windows 98<!-- what about ME? -->) never supported it. Windows 98 introduced a utility to convert existing hard disks from FAT16 to FAT32 without loss of data.\n\nIn the Windows NT line, native support for FAT32 arrived in [[Windows 2000]]. A free FAT32 driver for [[Windows NT 4.0]] was available from [[Winternals]], a company later acquired by Microsoft. The acquisition of the driver from official sources is no longer possible. Since 1998, Caldera's dynamically loadable [[DRFAT32]] driver could be used to enable FAT32 support in DR-DOS.<ref name="Caldera_1998_DRFAT32-RM"/><ref name="Caldera_1998_DRFAT32"/> The first version of DR-DOS to natively support FAT32 and LBA access was OEM DR-DOS 7.04 in 1999. That same year [[Intelligent Micro Software|IMS]] introduced native FAT32 support with [[REAL/32]] 7.90, and [[IBM 4690 OS]] added FAT32 support with version 2.<ref name="IBM_4690_User_Guide" /> [[Ahead Software]] provided another dynamically loadable FAT32.EXE driver for DR-DOS 7.03 with [[Nero Burning ROM]] in 2004.<!-- with copyrights 2002-2004 --> IBM introduced native FAT32 support with OEM PC DOS 7.1 in 1999.\n\nTwo partition types have been reserved for FAT32 partitions, <code>[[Partition type#PID 0Bh|0x0B]]</code> and <code>[[Partition type#PID 0Ch|0x0C]]</code>. The latter type is also named '''FAT32X''' in order to indicate usage of LBA disk access instead of CHS.<ref name="Caldera_1998_DRFAT32-RM"/><ref name="PowerQuest_1998_PQ4" /><ref name="Livingstone_1998_FAT32X" /><ref name="Duitz_2001_FAQ" /><ref name="Costanzo_1998_FAT32X" /> On such partitions, CHS-related geometry entries, namely the [[MBR partition entry|CHS sector address]]es in the MBR as well as the number of [[BPB sectors per track|sectors per track]] and the [[BPB number of heads|number of heads]] in the EBPB record, may contain no or misleading values and should not be used.<ref name="PowerQuest_1998_FAT32X" /><ref name="Duitz_2001_FAQ" /><ref name="Costanzo_1998_FAT32X" />"}},
{"article_title": "Cable modem", "pageid": "53259", "revid": "1057123829", "timestamp": "2021-11-25T16:23:00Z", "history_paths": [["Cable modem --- Introduction ---", "History"]], "categories": ["digital cable", "cable television technology", "modems", "internet access"], "heading_tree": {"Cable modem --- Introduction ---": {"History": {"MITRE Cablenet": {}, "IEEE 802.3b (10BROAD36)": {}, "IEEE 802.7": {}, "Hybrid networks": {}, "LANcity": {}, "Zenith homeworks": {}, "Com21": {}, "CDLP": {}, "DVB/DAVIC": {}, "IEEE 802.14": {}, "IETF": {}, "DOCSIS": {}, "Multimedia over Coax Alliance": {}}, "Multimedia terminal adapter{{anchor|MTA}}": {}, "Network architectural functions": {}, "Cable modem flap": {}, "Known vulnerabilities": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cable modem --- Introduction ---|History": "[[Internet Experiment Note|Internet Experiment Note (IEN)]] 96<ref name="IEN 96">[http://ftp.rfc-editor.org/in-notes/ien/ien96.txt IEN 96] - The [[MITRE]] Cablenet Project</ref> (1979) describes an early [[Radio frequency|RF]] cable modem system.  From pages 2 and 3 of IEN 96:\n<blockquote>The Cable-Bus System\n\nThe MITRE/Washington Cablenet system is based on a technology developed at MITRE/Bedford. Similar cable-bus systems are in operation at a number of government sites, e.g. [[Walter Reed Army Medical Center|Walter Reed Army Hospital]], and the [[NASA]] [[Lyndon B. Johnson Space Center|Johnson Space Center]], but these are all standalone, local-only networks.\n\nThe system uses standard [[Cable television|Community Antenna Television]] (CATV) [[coaxial cable]] and microprocessor based Bus Interface Units (BIUs) to connect subscriber [[computer]]s and [[Terminal (telecommunication)|terminals]] to the cable. ... The cable bus consists of [[Four-wire circuit|two parallel]] coaxial cables, one inbound and the other outbound. The inbound cable and outbound cable are connected at one end, the [[Cable television headend|headend]], and [[Electrical termination|electrically terminated]] at their other ends. This architecture takes advantage of the well developed [[Simplex communication|unidirectional]] CATV [[Distribution amplifier|components]].<ref name="RF Micro Devices, Inc. Whitepaper Describing Historical CATV Components">{{cite web|url=http://www.piedmontscte.org/resources/CATV+Hybrid+Amplifier+Modules+Past$2C+Present$2C+FutureWP.pdf|title=RF Micro Devices, Inc. Whitepaper Describing Historical CATV Components|website=Piedmontscte.org|access-date=2016-08-03|quotation=Amplifiers are one of the common components used in CATV system}}</ref> The [[Network topology|topology]] is dendritic (i.e. [[Tree topology|branched like a tree]]).<br/>\n...<br/>\nThe BIUs contain [[Radio frequency|Radio Frequency]] (RF) modems which [[Modulation|modulate]] a [[carrier signal]] to transmit [[Digital signal (electronics)|digital]] [[Information theory|information]] using 1 [[Hertz|MHz]] of the available [[Bandwidth (signal processing)|bandwidth]] in the 24 MHz frequency range. The remainder of the 294 MHz bandwidth can be used to carry other [[communication channel]]s, such as [[Terrestrial television|off-the-air]] [[NTSC|TV]], [[FM radio|FM]], [[Closed-circuit television|closed circuit TV]], or a [[Voice frequency|voice]] [[Digital Telephony|telephone system]], or, other digital channels. The [[Bit rate|data rate]] of our test-bed system is 307.2 [[Kilobit per second|kbps]].</blockquote>\n\n The [[Institute of Electrical and Electronics Engineers|IEEE]] [[IEEE 802|802 Committee]] defined [[10BROAD36]] in [[10BROAD36|802.3b-1985]]<ref name="IEEE 802.3b (10BROAD36) Standard">[http://standards.ieee.org/findstds/standard/802.3b-1985.html IEEE 802.3b-1985 (10BROAD36)] - Supplement to 802.3: Broadband Medium Attachment Unit and Broadband Medium Specifications, Type 10BROAD36 (Section 11)</ref> as a 10 [[Bit rate|Mbit/s]] [[IEEE 802.3]]/[[Ethernet]] broadband system to run up to {{convert|3600|m}} over CATV coax network cabling.  The word ''[[broadband]]'' as used in the original IEEE 802.3 specifications implied operation in [[Multiplexing#Frequency-division multiplexing|frequency-division multiplexed]] ([[Frequency-division multiplexing|FDM]]) channel bands as opposed to digital ''[[baseband]]'' [[Square wave|square-waveform]] [[modulation]]s (also known as [[Line code|line coding]]), which begin near zero [[Hertz|Hz]] and [[Fourier series|theoretically]] consume [[Square wave#Fourier Analysis|infinite]] [[Bandwidth (signal processing)|frequency bandwidth]].  (In real-world systems, higher-order [[Signal (electrical engineering)|signal]] [[Square wave#Fourier Analysis|components]] become indistinguishable from background [[Signal-to-noise ratio|noise]].)  In the market [[10BROAD36]] equipment was not developed by many vendors nor deployed in many user networks as compared to equipment for IEEE 802.3/[[Ethernet]] [[Baseband#Baseband Ethernet|baseband]] standards such as [[10BASE5]] (1983), [[10BASE2]] (1985), [[Ethernet over twisted pair|10BASE-T]] (1990), etc.\n\n The [[Institute of Electrical and Electronics Engineers|IEEE]] 802 Committee also specified a broadband CATV digital networking standard in 1989 with [[IEEE 802.7|802.7-1989]].<ref name="IEEE 802.7-1989 Standard">{{cite web|url=http://standards.ieee.org/findstds/standard/802.7-1989.html |title=IEEE SA - 802.7-1989 - Local Area Networks: IEEE Recommended Practice: Broadband Local Area Networks |website=Standards.ieee.org |date=1990-03-09 |access-date=2016-08-03}}</ref>  However, like [[10BROAD36]], 802.7-1989 saw little commercial success.\n\n Hybrid Networks developed, demonstrated and patented the first high-speed, asymmetrical cable modem system in 1990. A key Hybrid Networks insight was that in the nascent days of the Internet, data downloading constitutes the majority of the data traffic, and this can be served adequately with a highly asymmetrical data network (i.e. a large downstream data pipe and many small upstream data pipes).  This allowed CATV operators to offer high speed data services immediately without first requiring an expensive system upgrade.  Also key was that it saw that the upstream and downstream communications could be on the same or different communications media using different protocols working in each direction to establish a closed loop communications system. The speeds and protocols used in each direction would be very different. The earliest systems used the [[public switched telephone network]] (PSTN) for the return path since very few cable systems were bi-directional. Later systems used CATV for the upstream as well as the downstream path. Hybrid's system architecture is used for most cable modem systems today.\n\n LANcity was an early pioneer in cable modems, developing a proprietary system that was widely deployed in the U.S. LANcity, which was led by the Iranian-American engineer [[Rouzbeh Yassini]], was then acquired by [[Bay Networks]].<ref>{{Cite web|url=https://www.cnet.com/news/bay-networks-to-acquire-lancity/|title=Bay Networks to acquire LANcity|last=staff|first=CNET News|website=CNET|language=en|access-date=2019-09-05}}</ref> Bay Networks was subsequently acquired by [[Nortel]].<ref>{{Cite web|url=https://www.sfgate.com/business/article/Telecom-Giants-To-Merge-Bay-Networks-bought-by-3003305.php|title=Telecom Giants To Merge / Bay Networks bought by Nortel for $7.2 billion|last1=Marshall|first1=Jonathan|last2=Writer|first2=Chronicle Staff|date=1998-06-16|website=SFGate|access-date=2019-09-05}}</ref> Nortel at the time had formed a joint-venture with [[Antec]] called [[Arris Group|ARRIS]] Interactive.<ref>{{Cite web|url=https://www.cnet.com/news/nortel-ups-stake-in-joint-venture-with-antec/|title=Nortel ups stake in joint venture with Antec|website=CNET|language=en|access-date=2019-09-05}}</ref> Because of contractual agreements with Antec involving this joint venture, Nortel spun the LANCity group out into the ARRIS Interactive joint-venture. ARRIS continues to make cable modems and [[cable modem termination system]] (CMTS) equipment compliant with the [[DOCSIS]] standard.\n\n [[Zenith Electronics|Zenith]] offered a cable modem technology using its own protocol which it introduced in 1993, being one of the first cable modem providers. The [[Zenith Cable Modem]] technology was used by several cable television systems in the United States and other countries, including Cox Communications San Diego, Knology in the Southeast United States, [[Ameritech]]'s Americast service (later to be sold off to [[Wide Open West]] after the SBC / Ameritech merger), Cogeco in Hamilton Ontario and Cablevision du Nord de Qu\u00e9bec in Val-d'Or.<ref>{{cite news|title=Americast Places $1-Billion Order for Set-Top Boxes |newspaper=[[Los Angeles Times]]|author=Sallie Hofmeister|url=http://articles.latimes.com/1996-08-23/business/fi-36983_1_set-top-boxes|access-date=2010-08-28 | date=1996-08-23}}</ref> Zenith Homeworks used BPSK (Bi-Phase Shift Keyed) modulation to achieve 500 Kbit/sec in 600 kHz, or 4 Mbit/sec in 6 MHz.<ref>{{cite book|title=Network Design: Principles and Applications|author=Gilbert Held|year=2000|page=765|publisher=Auerbach Publications|url=https://books.google.com/books?id=06uBL8vGpoIC&q=zenith+cable+modem&pg=PA765|isbn=978-0-8493-0859-8}}</ref>\n\n {{main|Com21}}\n[[Com21]] was another early pioneer in cable modems, and quite successful until proprietary systems were made obsolete by the DOCSIS standardization. The Com21 system used a ''ComController'' as central bridge in CATV network head-ends, the ComPort cable modem in various models and the NMAPS management system using [[HP OpenView]] as platform. Later they also introduced a return path multiplexer to overcome noise problems when combining return path signals from multiple areas. The proprietary protocol was based on [[Asynchronous Transfer Mode]] (ATM). The central ComController switch was a modular system offering one downstream channel (transmitter) and one management module. The remaining slots could be used for upstream receivers (2 per card), dual Ethernet 10BaseT and later also Fast-Ethernet and ATM interfaces. The ATM interface became the most popular, as it supported the increasing bandwidth demands and also supported [[VLAN]]s.\nCom21 developed a DOCSIS modem, but the company filed for bankruptcy in 2003 and closed. The DOCSIS CMTS assets of COM21 were acquired by [[Arris Group|ARRIS]].\n\n CDLP was a proprietary system manufactured by [[Motorola]]. CDLP [[customer premises equipment]] (CPE) was capable of both [[PSTN|PSTN (telephone network)]] and [[cable network|radio frequency (cable network)]] return paths. The PSTN-based service was considered 'one-way cable' and had many of the same drawbacks as [[satellite Internet]] service; as a result, it quickly gave way to "two-way cable." Cable modems that used the RF cable network for the return path were considered 'two-way cable', and were better able to compete with the bi-directional [[digital subscriber line]] (DSL) service. The standard is in little use now while new providers use, and existing providers having changed to the DOCSIS standard. The Motorola CDLP proprietary CyberSURFR is an example of a device that was built to the CDLP standard, capable of a peak 10 [[Mbit/s]] downstream and 1.532 Mbit/s upstream. CDLP supported a maximum downstream bandwidth of 30 Mbit/s which could be reached by using several cable modems.\n\nThe [[Australia]]n ISP [[BigPond]] employed this system when it started cable modem tests in 1996. For a number of years [[cable Internet access]] was only available in [[Sydney]], [[Melbourne]] and [[Brisbane]] via CDLP. This network ran parallel to the newer DOCSIS system for several years. In 2004, the CDLP network was terminated and replaced by DOCSIS.\n\nCDLP has been also rolled out at the French cable operator [[Numericable]] before upgrading its IP broadband network using DOCSIS.\n\n [[Digital Video Broadcasting]] ([[Digital Video Broadcasting|DVB]]) and [[DAVIC|Digital Audio Visual Council]] (DAVIC) are European-formed organizations that developed some cable modem standards.  However, these standards have not been as widely adopted as DOCSIS.\n\n In the mid-1990s the [[IEEE 802]] committee formed a subcommittee (802.14)<ref name="IEEE 802.14 WG Homepage">{{cite web|url=http://walkingdog.com/ |title=WalkingDog.com |access-date=2012-05-13 |url-status=bot: unknown |archive-url=https://web.archive.org/web/19961226193928/http://walkingdog.com/ |archive-date=1996-12-26 }} The IEEE 802.14 Working Group used WalkingDog.com as its web site.</ref> to develop a standard for cable modem systems.  IEEE 802.14 developed a draft standard, which was [[Asynchronous Transfer Mode|ATM-based]].  However, the [[IEEE 802.14|802.14]] working group was disbanded when North American [[multiple system operator|multi system operators]] ([[multiple system operator|MSOs]]) instead backed the then-fledgling [[DOCSIS|DOCSIS 1.0]] specification, which generally used [[Best-effort|best efforts service]] and was [[Internet Protocol|IP-based]] (with extension [[Code point|codepoints]] to support [[Asynchronous Transfer Mode|ATM]]<ref name="DOCSIS RFI 1.0-I01">[http://www.cablelabs.com/specifications/SP-RFI-I01-970326.pdf DOCSIS RFI 1.0-I01 (March 26, 1997)] {{webarchive|url=https://web.archive.org/web/20110525094347/http://www.cablelabs.com/specifications/SP-RFI-I01-970326.pdf |date=May 25, 2011 }} (See section 6.2.3 for the DOCSIS [[Asynchronous Transfer Mode|ATM]] codepoint. See sections 6.1.2.3, 6.2.5.3, 6.4.7, 9, and 9.2.2 for DOCSIS 1.0 [[Quality of service|QoS]] mechanisms.)</ref> for [[Quality of service|QoS]] in the future). [[multiple system operator|MSOs]] were interested in quickly deploying service to compete for [[Internet access|broadband Internet access]] customers instead of waiting on the slower, iterative, and deliberative processes of standards development committees.  Albert A. Azzam was Secretary of the IEEE 802.14 Working Group,<ref name="IEEE 802.14 WG Officers">{{cite web|url=http://www.walkingdog.com/catv/officers.htm |title=IEEE 802.14 WG Officers |access-date=2012-05-13 |url-status=bot: unknown |archive-url=https://web.archive.org/web/19970129161548/http://www.walkingdog.com/catv/officers.htm |archive-date=1997-01-29 }}</ref> and his book, ''High-Speed Cable Modems'',<ref name="Azzam - High Speed Cable Modems">Albert A. Azzam, ''High-Speed Cable Modems'' {{ISBN|978-0-07-006417-1}}</ref> describes many of the proposals submitted to 802.14.\n\n Although the [[Internet Engineering Task Force]] (IETF) generally does not generate complete cable modem standards, the IETF chartered [[Working group|Working Groups]] ([[Working group|WGs]]) that produced various standards related to cable modem technologies (including 802.14, DOCSIS, [[PacketCable]], and others).  In particular, the IETF WGs on IP over Cable Data Network (IPCDN)<ref name="IETF IPCDN WG">{{cite web|url=http://tools.ietf.org/wg/ipcdn/ |title=Ipcdn Status Pages |website=Tools.ietf.org |access-date=2016-08-03}}</ref> and IP over [[Digital Video Broadcasting]] (DVB)<ref name="IETF IPDVB WG">{{cite web|url=http://tools.ietf.org/wg/ipdvb/ |title=Ipdvb Status Pages |website=Tools.ietf.org |access-date=2016-08-03}}</ref> produced some standards applicable to cable modem systems, primarily in the areas of [[Simple Network Management Protocol]] (SNMP) [[Management information base|Management Information Bases]] ([[Management information base|MIBs]]) for cable modems and other networking equipment that operates over CATV [[Television network|networks]].\n\n {{main|DOCSIS}}\nIn the late 1990s, a consortium of US [[Multiple system operator|cable operators]], known as "MCNS" formed to quickly develop an open and interoperable cable modem specification. The group essentially combined technologies from the two dominant proprietary systems at the time, taking the [[physical layer]] from the [[Motorola]] [[#CDLP|CDLP]] system and the [[MAC layer]] from the LANcity system. When the initial specification had been drafted, the MCNS consortium handed over control of it to [[CableLabs]] which maintained the specification, promoted it in various standards organizations (notably [[SCTE]] and [[ITU]]), developed a certification testing program for cable modem equipment, and has since drafted multiple extensions to the original specification.\n\nWhile deployed [[DOCSIS|DOCSIS RFI 1.0]] equipment generally only supports [[Best-effort|best efforts service]], the DOCSIS RFI 1.0 Interim-01 document discussed [[Quality of service|QoS]] extensions and mechanisms using [[Integrated services|IntServ]], [[Resource Reservation Protocol|RSVP]], [[Real-time Transport Protocol|RTP]], and Synchronous Transfer Mode (STM) [[telephony]] (as opposed to [[Asynchronous Transfer Mode|ATM]]).<ref name="DOCSIS RFI 1.0-I01"/> [[DOCSIS|DOCSIS RFI 1.1]]<ref name="DOCSIS RFI 1.1-I01">[https://web.archive.org/web/20200729172439/https://www.cablelabs.com/specifications/SP-RFIv1.1-I01-990311.pdf DOCSIS RFI 1.1-I01 (March 11, 1999)] (See section 8 and Appendix M.)</ref> later added more robust and standardized [[Quality of service|QoS]] mechanisms to DOCSIS. [[DOCSIS|DOCSIS 2.0]] added support for [[Synchronous Code Division Multiple Access|S-CDMA]] [[PHY]], while DOCSIS 3.0 added [[Internet Protocol version 6|IPv6]] support and [[channel bonding]] to allow a single cable modem to use concurrently more than one upstream channel and more than one downstream channel in parallel.\n\nVirtually all cable modems operating in the field today are compliant with one of the DOCSIS versions. Because of the differences in the European [[PAL]] and USA's [[NTSC]] systems two main versions of DOCSIS exist, DOCSIS and EuroDOCSIS. The main differences are found in the width of RF-channels: 6 MHz for the USA and 8 MHz for Europe. A third variant of DOCSIS was developed in [[Japan]] and has seen limited deployment in that country.\n\nAlthough interoperability "was the whole point of the DOCSIS project,"<ref>{{cite web|url=http://stuff.mit.edu/afs/sipb.mit.edu/contrib/doc/DOCSIS/overview/certification/Certification_Overview.pdf |title=DOCSIS Modem Interoperability and Certification Overview |website=Stuff.mit.edu |access-date=2016-08-03}}</ref> most cable operators only approve a very restricted list of cable modems on their network,<ref>{{cite web |url=http://teksavvy.com/en/residential/internet/cable |title=Cable |website=TekSavvy.com |access-date=2016-08-03 |archive-url=https://web.archive.org/web/20160801135543/http://teksavvy.com/en/residential/internet/cable |archive-date=2016-08-01 |url-status=dead }}</ref><ref>{{cite web|url=http://www.vmedia.ca/en/internet/compatible-modems |title=Compatible Modems |website=vmedia.ca |access-date=2021-10-27}}</ref><ref>{{cite web |url=http://www.acanac.ca/Approved_Modems_Ontario.html |title=Unlimited Internet Plans Quebec | Cable, Fibre Optic | Acanac |website=Acanac.ca |access-date=2016-08-03 |archive-url=https://web.archive.org/web/20150512090341/http://www.acanac.ca/Approved_Modems_Ontario.html |archive-date=2015-05-12 |url-status=dead }}</ref><ref>{{Cite web|url=http://www.worldline.ca/services/high-speed-internet/cable/75/|title=Fast Unlimited Download High Speed Cable 75 Internet Plus Home Phone Bundle|website=www.worldline.ca|language=en|access-date=2018-04-23}}</ref> identifying the 'allowed' modems by their brand, models, sometimes firmware version and occasionally going as far as imposing a hardware version of the modem, instead of simply allowing a supported DOCSIS version.\n\n {{main|Multimedia over Coax Alliance}}In 2004, the Multimedia over Coax Alliance (MoCA) was established to develop industry standard for the connected home, using the existing coaxial cabling. Initially developed for in-home networking with MoCA 1.0/1.1, the MoCA standards has continued to develop with MoCA 2.0/2.1 in 2010 and MoCa 2.5 in 2016.\n\nIn 2017, Multimedia over Coax Alliance introduced MoCA Access specification, based on the MoCA 2.5 standard, suitable for addressing broadband network access in-building using coaxial cabling.<ref>{{Cite web|url=http://www.mocalliance.org/access/index.htm|title=MoCA Access\u2122|last=KMCreative|website=www.mocalliance.org|language=en|access-date=2017-10-03}}</ref> MoCA Access extends MoCA 2.5 in-home networking to fit operators and ISPs that are installing fiber-to-the-basement/drop point (FTTB/FTTdp) and want to use the existing coax for connection to each apartment or house.""}},
{"article_title": "Pig iron", "pageid": "53694", "revid": "1052461768", "timestamp": "2021-10-29T08:19:09Z", "history_paths": [["Pig iron --- Introduction ---", "History"]], "categories": ["ancient egyptian technology", "ancient roman technology", "chinese inventions", "ferrous alloys", "iron", "metalworking", "smelting", "steelmaking"], "heading_tree": {"Pig iron --- Introduction ---": {"History": {}, "Uses": {"Modern uses": {}}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Pig iron --- Introduction ---|History": "{{see also|History of ferrous metallurgy}}\n[[File:Casting pig iron, Iroquois smelter, Chicago.jpg|thumb|Casting pig iron, Iroquois smelter, Chicago, between 1890 and 1901]]\nSmelting and producing [[wrought iron]] was known in ancient Europe and the Middle East, but it was produced in [[bloomery|bloomeries]] by direct reduction. Pig iron was not produced in Europe before the [[Middle Ages]]. The [[China|Chinese]] were making pig iron by the later [[Zhou dynasty]] (which ended in 256 BC).<ref name="Wagner">Wagner, Donald. ''Iron and Steel in Ancient China''. Leiden 1996: [[Brill Publishers]]</ref> Furnaces such as [[Lapphyttan]] in Sweden may date back to the 12th century; and some in [[County of Mark|Mark]] (today part of [[Westphalia]], Germany) to the 13th.<ref>Several papers in ''The importance of ironmaking: technical innovation and social change: papers presented at the Norberg Conference, May 1995'' ed. Gert Magnusson (Jernkontorets Berghistoriska Utskott H58, 1995), 143-179.</ref> It remains to be established whether these northern European developments derive from Chinese ones. Wagner<ref>{{Cite journal|url=https://www.persee.fr/doc/befeo_0336-1519_1995_num_82_1_2347|title=Donald B. Wagner : Iron and Steel in Ancient China|journal=Bulletin de l'\u00c9cole Fran\u00e7aise d'Extr\u00eame-Orient|year=1995|volume=82|issue=1|pages=426\u2013428|last1=Golas|first1=Peter}}</ref> has postulated a possible link via Persian contacts with China along the [[Silk Road]] and Viking contacts with Persia,<ref name="Wagner"/> but there is a chronological gap between the Viking period and Lapphyttan.  \n\nThe phase transition of the iron into liquid in the furnace was an ''avoided'' phenomenon, as [[Decarburization|decarburizing]] the pig iron into steel was an extremely tedious process using medieval technology."}},
{"article_title": "Digital media", "pageid": "53723", "revid": "1060094060", "timestamp": "2021-12-13T12:27:42Z", "history_paths": [["Digital media --- Introduction ---", "History"]], "categories": ["digital media", "information science", "library science", "mass media", "mass media technology", "articles containing video clips"], "heading_tree": {"Digital media --- Introduction ---": {"Digital media": {}, "History": {"Digital computers": {}, "\"As We May Think\"": {}, "Digital multimedia": {}}, "Impact": {"The digital revolution": {}, "Disruption in industry": {}, "Individual as content creator": {}, "Web-only news": {}, "Copyright challenges": {}}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Digital media --- Introduction ---|History": "Codes and information by machines were first conceptualized by [[Charles Babbage]] in the early 1800s. Babbage imagined that these codes would give him instructions for his Motor of Difference and Analytical Engine, machines that Babbage had designed to solve the problem of error in calculations.\nBetween 1822 and 1823, [[Ada Lovelace]], mathematics, wrote the first instructions for calculating numbers on Babbage engines. Lovelace's instructions are now believed to be the first computer program.\nAlthough the machines were designed to perform analysis tasks, Lovelace anticipated the possible social impact of computers and programming, writing. "For in the distribution and combination of truths and formulas of analysis, which may become easier and more quickly subjected to the mechanical combinations of the engine, the relationships and the nature of many subjects in which science necessarily relates in new subjects, and more deeply researched [\u2026] there are in all extensions of human power or additions to human knowledge, various collateral influences, in addition to the primary and primary object reached." Other old machine readable media include instructions for pianolas and [[weaving]] machines.\n[[File:Cabac1binar.png|thumb|Binary Code shown here which can used to represent the whole alphabet]]\n\nIt is estimated that in the year 1986 less than 1% of the world's media storage capacity was digital and in 2007 it was already 94%.<ref name="HilbertLopez2011">{{cite journal|title =The World's Technological Capacity to Store, Communicate, and Compute Information|first1= Martin|last1= Hilbert|first2= Priscila |last2=L\u00f3pez |date =2011|journal = [[Science (journal)|Science]]|volume= 332|issue =6025|pages= 60\u201365|doi = 10.1126/science.1200970 |pmid= 21310967|bibcode= 2011Sci...332...60H|s2cid= 206531385|url =  http://www.martinhilbert.net/WorldInfoCapacity.html/}} especially [http://www.sciencemag.org/content/suppl/2011/02/08/science.1200970.DC1/Hilbert-SOM.pdf Supporting online material]</ref> The year 2002 is assumed to be the year when human kind was able to store more information in digital than in analog media (the "beginning of the [[digital age]]").<ref name="Hilbertvideo2011">{{cite web|url=https://www.youtube.com/watch?v=iIKPjOuwqHo| archive-url=https://ghostarchive.org/varchive/youtube/20211030/iIKPjOuwqHo| archive-date=2021-10-30|title=World_info_capacity_animation|last=Martin Hilbert |date=11 June 2011|via=YouTube}}{{cbignore}}</ref>\n\n {{see also|Digital electronics|History of computing|History of computing hardware|History of programming languages|History of the transistor}}\n[[Image:Wikipedia in binary.gif|thumb|right|Digital codes, like [[binary code|binary]], can be changed without reconfiguring mechanical parts]]\n\nThough they used machine-readable media, Babbage's engines, player pianos, jacquard looms and many other early calculating machines were themselves [[analog computers]], with physical, mechanical parts. The first truly digital media came into existence with the rise of [[digital computer]]s.<ref name=stanford>{{cite encyclopedia|last=Copeland|first=B. Jack|title=The modern history of computing|url=http://plato.stanford.edu/entries/computing-history/|encyclopedia=The Stanford Encyclopedia of Philosophy|publisher=Stanford University|access-date=31 March 2014|date=Fall 2008}}</ref>  Digital computers use [[binary code]] and [[Boolean logic]] to store and process information, allowing one machine in one configuration to perform many different tasks. The first modern, programmable, digital computers, the [[Manchester Mark 1]] and the [[EDSAC]], were independently invented between 1948 and 1949.<ref name=stanford /><ref>{{cite news|title=Sci/tech pioneers recall computer creation|url=http://news.bbc.co.uk/2/hi/science/nature/317437.stm|access-date=29 March 2014|newspaper=BBC|date=15 April 1999}}</ref> Though different in many ways from modern computers, these machines had digital software controlling their [[logical operation]]s. They were encoded in [[binary code|binary]], a system of ones and zeroes that are combined to make hundreds of characters. The 1s and 0s of binary are the "digits" of digital media.<ref>{{cite web|url=http://www.thebetterindia.com/27331/12-projects-you-should-know-about-under-the-digital-india-initiative/|title=12 Projects You Should Know About Under the Digital India Initiative|date=2 July 2015}}</ref>\n\nIn 1959, the [[MOSFET|metal\u2013oxide\u2013silicon field-effect transistor]] (MOSFET, or MOS transistor) was invented by [[Mohamed Atalla]] and [[Dawon Kahng]] at [[Bell Labs]].<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960 - Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]]}}</ref><ref name="Lojek">{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |pages=321\u20133}}</ref> It was the first truly compact [[transistor]] that could be miniaturised and mass-produced for a wide range of uses.<ref name="Moskowitz">{{cite book |last1=Moskowitz |first1=Sanford L. |title=Advanced Materials Innovation: Managing Global Technology in the 21st century |date=2016 |publisher=[[John Wiley & Sons]] |isbn=9780470508923 |pages=165\u2013167 |url=https://books.google.com/books?id=2STRDAAAQBAJ&pg=PA165}}</ref> The MOSFET led to the development of [[microprocessors]], [[memory chip]]s, and digital [[telecommunication circuit]]s.<ref name="Colinge2016">{{cite book |last1=Colinge |first1=Jean-Pierre |last2=Greer |first2=James C.|title=Nanowire Transistors: Physics of Devices and Materials in One Dimension |date=2016 |publisher=[[Cambridge University Press]] |isbn=9781107052406 |page=2 |url=https://books.google.com/books?id=FvjUCwAAQBAJ&pg=PA2}}</ref> This led to the development of the [[personal computer]] (PC) in the 1970s, and the beginning of the [[microcomputer revolution]]<ref>{{cite book |last1=Malmstadt |first1=Howard V. |last2=Enke |first2=Christie G. |last3=Crouch |first3=Stanley R. |title=Making the Right Connections: Microcomputers and Electronic Instrumentation |date=1994 |publisher=[[American Chemical Society]] |isbn=9780841228610 |page=389 |url=https://books.google.com/books?id=lyJGAQAAIAAJ |quote=The relative simplicity and low power requirements of MOSFETs have fostered today's microcomputer revolution.}}</ref> and the [[Digital Revolution]].<ref name="triumph">{{cite web |title=The Foundation of Today's Digital World: The Triumph of the MOS Transistor |url=https://www.youtube.com/watch?v=q6fBEjf9WPw | archive-url=https://ghostarchive.org/varchive/youtube/20211030/q6fBEjf9WPw| archive-date=2021-10-30|publisher=[[Computer History Museum]] |access-date=21 July 2019 |date=13 July 2010}}{{cbignore}}</ref><ref name="Raymer">{{cite book |last1=Raymer |first1=Michael G. |title=The Silicon Web: Physics for the Internet Age |date=2009 |publisher=[[CRC Press]] |isbn=9781439803127 |page=365 |url=https://books.google.com/books?id=PLYChGDqa6EC&pg=PA365}}</ref><ref name="Wong">{{cite book |last1=Wong |first1=Kit Po |title=Electrical Engineering - Volume II |date=2009 |publisher=[[Encyclopedia of Life Support Systems|EOLSS Publications]] |isbn=9781905839780 |page=7 |url=https://books.google.com/books?id=4fI8CwAAQBAJ&pg=PA7}}</ref>\n\n While digital media did not come into common use until the late 20th century, the ''conceptual'' foundation of digital media is traced to the work of scientist and engineer [[Vannevar Bush]] and his celebrated essay "[[As We May Think]]," published in ''[[The Atlantic Monthly]]'' in 1945.<ref name=symposium>{{cite news|last=Simpson|first=Rosemary|title=50 years after "As We May Think": the Brown/MIT Vannevar Bush symposium|url=http://cs.brown.edu/~rms/50YearsAfter.pdf|access-date=29 March 2014|newspaper=Interactions|date=March 1996|author2=Allen Renear|author3=Elli Mylonas|author4=Andries van Dam|pages=47\u201367}}</ref> Bush envisioned a system of devices that could be used to help scientists, doctors, historians and others, store, analyze and communicate information.<ref name=symposium /> Calling this then-imaginary device a "[[memex]]", Bush wrote:\n<blockquote>The owner of the memex, let us say, is interested in the origin and properties of the bow and arrow. Specifically he is studying why the short Turkish bow was apparently superior to the English long bow in the skirmishes of the Crusades. He has dozens of possibly pertinent books and articles in his memex. First he runs through an encyclopedia, finds an interesting but sketchy article, leaves it projected. Next, in a history, he finds another pertinent item, and ties the two together. Thus he goes, building a trail of many items. Occasionally he inserts a comment of his own, either linking it into the main trail or joining it by a side trail to a particular item. When it becomes evident that the elastic properties of available materials had a great deal to do with the bow, he branches off on a side trail which takes him through textbooks on elasticity and tables of physical constants. He inserts a page of longhand analysis of his own. Thus he builds a trail of his interest through the maze of materials available to him.<ref name=AWMT>{{cite news|last=Bush|first=Vannevar|title=As We May Think|url=https://www.theatlantic.com/magazine/archive/1945/07/as-we-may-think/303881/?single_page=true|access-date=29 March 2014|newspaper=The Atlantic Monthly|date=1 July 1945}}</ref></blockquote>\nBush hoped that the creation of this memex would be the work of scientists after World War II.<ref name=AWMT /> Though the essay predated digital computers by several years, "As We May Think," anticipated the potential social and intellectual benefits of digital media and provided the conceptual framework for [[digital scholarship]], the [[World Wide Web]], [[wiki]]s and even [[social media]].<ref name=symposium /><ref>{{cite web|last=Mynatt|first=Elizabeth|title=As we may think: the legacy of computing research and the power of human cognition|url=http://www.cra.org/ccc/component/content/article/309-as-we-may-think-the-legacy-of-computing-research-and-the-power-of-human-cognition|publisher=Computing Research Association|access-date=30 March 2014|archive-url=https://web.archive.org/web/20140407053914/http://www.cra.org/ccc/component/content/article/309-as-we-may-think-the-legacy-of-computing-research-and-the-power-of-human-cognition|archive-date=7 April 2014|url-status=dead}}</ref> It was recognized as a significant work even at the time of its publication.<ref name=AWMT />\n\n {{See also|Data compression|Digital television|Image compression|Streaming media|Video coding format}}\n\nPractical digital [[multimedia]] [[digital distribution|distribution]] and [[streaming media|streaming]] was made possible by advances in [[data compression]], due to the impractically high memory, storage and bandwidth requirements of uncompressed media.<ref>{{cite book |last1=Lee |first1=Jack |title=Scalable Continuous Media Streaming Systems: Architecture, Design, Analysis and Implementation |date=2005 |publisher=[[John Wiley & Sons]] |isbn=9780470857649 |page=25 |url=https://books.google.com/books?id=7fuvu52cyNEC&pg=PA25}}</ref> The most important compression technique is the [[discrete cosine transform]] (DCT),<ref name="Zhu">{{cite book |last1=Ce |first1=Zhu |title=Streaming Media Architectures, Techniques, and Applications: Recent Advances: Recent Advances |date=2010 |publisher=IGI Global |isbn=9781616928339 |page=26 |url=https://books.google.com/books?id=Cb4dWYVJ_8AC&pg=PA26}}</ref> a [[lossy compression]] algorithm that was first proposed as an [[image compression]] technique by [[N. Ahmed|Nasir Ahmed]] at [[Kansas State University]] in 1972.<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I came up with the discrete cosine transform |journal=Digital Signal Processing |date=January 1991 |volume=1 |issue=1 |pages=4\u20135 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform}}</ref> The DCT algorithm was the basis for the first practical [[video coding format]], [[H.261]], in 1988.<ref name="Ghanbari">{{cite book |last1=Ghanbari |first1=Mohammed |title=Standard Codecs: Image Compression to Advanced Video Coding |date=2003 |publisher=[[Institution of Engineering and Technology]] |isbn=9780852967102 |pages=1\u20132 |url=https://books.google.com/books?id=7XuU8T3ooOAC&pg=PA1}}</ref> It was followed by more DCT-based [[video coding standards]], most notably the [[MPEG]] video formats from 1991 onwards.<ref name="Zhu"/> The [[JPEG]] [[image format]], also based on the DCT algorithm, was introduced in 1992.<ref name="t81">{{cite web |title=T.81 \u2013 DIGITAL COMPRESSION AND CODING OF CONTINUOUS-TONE STILL IMAGES \u2013 REQUIREMENTS AND GUIDELINES |url=https://www.w3.org/Graphics/JPEG/itu-t81.pdf |publisher=[[CCITT]] |date=September 1992 |access-date=12 July 2019}}</ref> The development of the [[modified discrete cosine transform]] (MDCT) algorithm led to the [[MP3]] [[audio coding format]] in 1994,<ref name="Guckert">{{cite web |last1=Guckert |first1=John |title=The Use of FFT and MDCT in MP3 Audio Compression |url=http://www.math.utah.edu/~gustafso/s2012/2270/web-projects/Guckert-audio-compression-svd-mdct-MP3.pdf |website=[[University of Utah]] |date=Spring 2012 |access-date=14 July 2019}}</ref> and the [[Advanced Audio Coding]] (AAC) format in 1999.<ref name=brandenburg>{{cite web|url=http://graphics.ethz.ch/teaching/mmcom12/slides/mp3_and_aac_brandenburg.pdf|title=MP3 and AAC Explained|last=Brandenburg|first=Karlheinz|year=1999|url-status=live|archive-url=https://web.archive.org/web/20170213191747/http://graphics.ethz.ch/teaching/mmcom12/slides/mp3_and_aac_brandenburg.pdf|archive-date=2017-02-13|access-date=2019-09-11}}</ref>"}},
{"article_title": "Fusion power", "pageid": "55017", "revid": "1062313600", "timestamp": "2021-12-27T18:20:32Z", "history_paths": [["Fusion power --- Introduction ---", "History"]], "categories": ["fusion power", "sustainable energy", "emerging technologies"], "heading_tree": {"Fusion power --- Introduction ---": {"Background": {"Mechanism": {}, "Cross section": {}, "Lawson criterion": {}, "Triple product: density, temperature, time": {}, "Energy capture": {}}, "Methods": {"Plasma behavior": {}, "Magnetic confinement": {}, "Inertial confinement": {}, "Magnetic or electric pinches": {}, "Inertial electrostatic confinement": {}, "Other": {}}, "Common tools": {"Heating": {}, "Measurement": {}, "Power production": {}, "Confinement": {"Unconfined": {}, "Magnetic confinement": {"Magnetic Mirror": {}, "Magnetic Loops": {}}, "Inertial confinement": {"Electrostatic confinement": {}}}}, "Fuels": {"Deuterium/tritium": {}, "Deuterium": {}, "Deuterium, helium-3": {}, "Proton, boron-11": {}}, "Material selection": {"Superconducting Materials": {}, "Containment considerations": {}, "Plasma-wall surface conditions": {}, "Selection of materials": {}}, "Safety and the environment": {"Accident potential": {}, "Magnet quench": {}, "Effluents": {}, "Radioactive waste": {}, "Nuclear proliferation": {}, "Fuel reserves": {}}, "Economics": {}, "Regulation": {}, "Geopolitics": {}, "Advantages": {}, "History": {"Early projects": {"Stellerator": {}, "Tokamak": {}, "Inertial confinement": {}, "Evolution": {}, "1980s": {}}, "1990s": {}, "2000s": {}, "2010s": {}, "2020s": {}}, "Records": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Fusion power --- Introduction ---|History": "{{Main|History of nuclear fusion}}\nThe history of fusion power began early in the 20th century as an inquiry into how stars powered themselves and expanded to incorporate a broad inquiry into the nature of matter and energy, while potential applications expanded to include warfare, rocket propulsion, and energy production. Unfortunately, generating electricity from fusion has been forecast to be 30 years in the future for the last 50 years and may still be that far off.<ref>{{Cite web|last=Scharping|first=Nathaniel|date=March 23, 2016|title=Why Nuclear Fusion Is Always 30 Years Away|url=https://www.discovermagazine.com/technology/why-nuclear-fusion-is-always-30-years-away|url-status=live|access-date=2021-06-15|website=Discover Magazine|language=en}}</ref>\n\nThe history is a convoluted mixture of investigations into [[nuclear physics]] and a parallel exploration of engineering challenges ranging from identifying appropriate materials and fuels, to improving heating and confinement techniques.[[File:IvyMike2.jpg|thumb|upright=1.5|The first man-made device to achieve [[Fusion energy gain factor#Ignition|ignition]] was the detonation of this fusion device, codenamed [[Ivy Mike]].]]\n[[File:Kink instability at Aldermaston.jpg|thumb|right|upright=1.5|Early photo of plasma inside a pinch machine (Imperial College 1950/1951)]]\n\nThe quest for fusion power has proceeded along multiple trajectories since the outset. Trajectories such as pinch designs fell away as they confronted obstacles that have yet to be surmounted. The survivors include magnetic confinement approaches such as tokamak and stellarator, along with ICF devices approaches such as laser and electrostatic confinement.\n\nThe first successful man-made fusion device was the [[boosted fission weapon]] tested in 1951 in the [[Greenhouse Item]] test. The first true fusion weapon was 1952's [[Ivy Mike]], and the first practical example was 1954's [[Castle Bravo]].\n\n \n The stellerator was the first candidate, preceding the better-known tokamak. It was pioneered by [[Lyman Spitzer]]. While fusion did not immediately transpire, the effort led to the creation of the [[Princeton Plasma Physics Laboratory]].<ref>{{Cite journal|last=Stix|first=T. H.|date=1998|title=Highlights in early stellarator research at Princeton|url=http://inis.iaea.org/Search/search.aspx?orig_q=RN:30002355|journal=Helical System Research|language=en}}</ref><ref>{{Cite tech report|last=Johnson|first=John L.|date=2001-11-16|title=The Evolution of Stellarator Theory at Princeton|url=https://www.osti.gov/biblio/792587-fxKdXU/native/|language=en|doi=10.2172/792587|osti=792587}}</ref>\n\nThe first experiment to achieve controlled [[thermonuclear fusion]] was accomplished using Scylla I at LANL in 1958.<ref name="Phillips, James 2013" /> Scylla I was a \u03b8-pinch machine, with a cylinder full of deuterium.<ref name="Seife, Charles 2008" /><ref name="Phillips, James 2013" />\n\n The concept of the tokamak originated in 1950\u20131951 from [[Igor Tamm|I.E. Tamm]] and [[Andrei Sakharov|A.D. Sakharov]] in the [[Soviet Union]]. The tokamak essentially combined a low-power pinch device with a low-power stellarator.<ref name=":14" />\n\n[[Andrei Sakharov|A.D. Sakharov]]'s group constructed the first tokamaks, achieving the first quasistationary fusion reaction.<ref>{{Cite book|last=Irvine|first=Maxwell|url=https://www.worldcat.org/title/nuclear-power-a-very-short-introduction/oclc/920881367&referer=brief_results|title=Nuclear power: a very short introduction|date=2014|publisher=Oxford University Press|isbn=978-0-19-958497-0|location=Oxford|language=en|oclc=920881367}}</ref><sup>:90</sup>\n\n \nLaser fusion was suggested in 1962 by scientists at LLNL, shortly after the invention of the laser in 1960. [[Inertial confinement fusion]] (using lasers) research began as early as 1965.{{multiple image\n | total_width = 440\n | image1 = Shiva amplifier chains.jpg\n | caption1 = Shiva laser, 1977, the largest ICF laser system built in the seventies\n | image2 = The Tandem Mirror Experiment.jpg\n | caption2 = The Tandem Mirror Experiment (TMX) in 1979 }}\n\nSeveral laser systems were built at LLNL. These included the [[Argus laser|Argus]], the [[Cyclops laser|Cyclops]], the [[Janus laser|Janus]], the [[Long path laser|long path]], the [[Shiva laser]], and the [[Nova (laser)|Nova]].<ref>{{cite journal | doi = 10.1088/0029-5515/25/9/063 | volume=25 | title=Highlights of laser fusion related research by United Kingdom universities using the SERC Central Laser Facility at the Rutherford Appleton Laboratory | year=1985 | journal=Nuclear Fusion | pages=1351\u20131353 | last1 = Key | first1 = M.H.| issue=9 }}</ref>\n\nLaser advances included frequency-tripling crystals that transformed infrared laser beams into ultraviolet beams and "chirping", which changed a single wavelength into a full spectrum that could be amplified and then reconstituted into one frequency.<ref>{{Cite book |title=Inertial confinement nuclear fusion : a historical approach by its pioneers|date=2007|publisher=Foxwell & Davies (UK)|editor=Verlarde, G. |editor2=Carpintero\u2013Santamar\u00eda, Natividad |isbn=978-1-905868-10-0|location=London |oclc=153575814}}</ref> Laser research ate money as well, consuming over one billion dollars in the 1980s.<ref name="NRDC">{{cite web|author1=Matthew McKinzie|author2=Christopher E. Paine|date=2000|title=When peer review fails : The Roots of the National Ignition Facility (NIF) Debacle|url=http://www.nrdc.org/nuclear/nif2/findings.asp|access-date=30 October 2014|publisher=National Resources Defense Council}}</ref>\n\n Over time the "advanced tokamak" concept emerged, which included non-circular plasma, internal diverters and limiters, superconducting magnets, and operation in the so-called "H-mode" island of increased stability.<ref>{{Citation|last=Kusama|first=Y.|title=Requirements for Diagnostics in Controlling Advanced Tokamak Modes|date=2002|work=Advanced Diagnostics for Magnetic and Inertial Fusion|pages=31\u201338|editor-last=Stott|editor-first=Peter E.|place=Boston, MA|publisher=Springer US|language=en|doi=10.1007/978-1-4419-8696-2_5|isbn=978-1-4419-8696-2|editor2-last=Wootton|editor2-first=Alan|editor3-last=Gorini|editor3-first=Giuseppe|editor4-last=Sindoni|editor4-first=Elio}}</ref> The compact tokamak, with the magnets on the inside of the vacuum chamber.<ref>{{Cite journal|last=Menard|first=J. E.|date=2019-02-04|title=Compact steady-state tokamak performance dependence on magnet and core physics limits|url= |journal=Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=377|issue=2141|pages=20170440|doi=10.1098/rsta.2017.0440|pmid=30967044|pmc=6365855|bibcode=2019RSPTA.37770440M|issn=1364-503X}}</ref><ref>{{Cite journal|last=Kaw|first=P.K|date=1999|title=Steady state operation of tokamaks|journal=Nuclear Fusion|volume=39|issue=11|pages=1605\u20131607|doi=10.1088/0029-5515/39/11/411|issn=0029-5515}}</ref>[[File:TMX Baseball Coils.jpg|thumb|Magnetic mirrors suffered from end losses, requiring high power, complex magnetic designs, such as the baseball coil pictured here.]]\n{{multiple image\n | image1 = Novette laser.jpg\n | width1 = 150\n | caption1 = The Novette target chamber (metal sphere with diagnostic devices protruding radially), which was reused from the [[shiva laser|Shiva]] project and two newly built laser chains visible in background.\n | image2 = Fusion target implosion on NOVA laser.jpg\n | width2 = 150\n | caption2 = Inertial confinement fusion implosion on the [[Nova laser]] during the 1980s was a key driver of fusion development.}}\n\n The [[Tore Supra]], [[Joint European Torus|JET]], [[T-15 (reactor)|T-15]], and [[JT-60]] tokamaks were built in the 1980s.<ref>{{cite web|url=http://www-drfc.cea.fr/gb/cea/ts/ts.htm |title=Tore Supra |access-date=February 3, 2016 |url-status=dead |archive-url=https://web.archive.org/web/20121115112229/http://www-drfc.cea.fr/gb/cea/ts/ts.htm |archive-date=November 15, 2012 }}</ref><ref>{{Cite journal|last=Smirnov|first=V.P.|date=2009-12-30|title=Tokamak foundation in USSR/Russia 1950\u20131990|journal=Nuclear Fusion|volume=50|issue=1|pages=014003|doi=10.1088/0029-5515/50/1/014003|issn=0029-5515}}</ref> In 1984, Martin Peng of ORNL proposed the [[spherical tokamak]] with a much smaller radius.<ref>Y-K Martin Peng, "Spherical Torus, Compact Fusion at Low Yield"., ORNL/FEDC-87/7 (December 1984)</ref> It used a single large conductor in the center, with magnets as half-rings off of this conductor. The aspect ratio fell to as low as 1.2.<ref name=":21">{{Cite journal|last=Sykes|first=Alan|date=1997|title=High \u03b2 produced by neutral beam injection in the START (Small Tight Aspect Ratio Tokamak) spherical tokamak|url=http://aip.scitation.org/doi/10.1063/1.872271|journal=Physics of Plasmas|language=en|volume=4|issue=5|pages=1665\u20131671|doi=10.1063/1.872271|bibcode=1997PhPl....4.1665S|issn=1070-664X}}</ref><sup>:B247</sup><ref name=":22">{{Cite book|last=Braams, C. M. |title=Nuclear fusion: half a century of magnetic confinement fusion research|author2=Stott, P. E. |year=2002|isbn=978-0-367-80151-9|oclc=1107880260}}</ref><sup>:225</sup> Peng's advocacy caught the interest of [[Derek Robinson (physicist)|Derek Robinson]], who built the [[Small Tight Aspect Ratio Tokamak]], (START).<ref name=":21" />\n\n <!-- {{multiple image\n | width1 = 220\n | image1 = [[WP:NFCC]] violation: Z-machine480.jpg\n | caption1 = Z Machine (a pinch at SNL) went through a number of upgrades during the mid to late nineties }} -->\n\nIn 1991, the Preliminary Tritium Experiment at the [[Joint European Torus]] achieved the world's first controlled release of fusion power.<ref>{{Cite journal|title=Neutron measurements from the preliminary tritium experiment at JET (invited) |journal=Review of Scientific Instruments |volume=63 |issue=10 |pages=4511\u20134516 |date=2006-06-16 |doi = 10.1063/1.1143707|last1 = Jarvis|first1 = O. N}}</ref>\n\nIn 1996, Tore Supra created a plasma for two minutes with a current of almost 1 million amperes, totaling 280 MJ of injected and extracted energy.<ref>{{Cite journal|last=Garin|first=Pascal|date=October 2001|title=Actively cooled plasma facing components in Tore Supra|url=http://dx.doi.org/10.1016/s0920-3796(01)00242-3|journal=Fusion Engineering and Design|volume=56-57|pages=117\u2013123|doi=10.1016/s0920-3796(01)00242-3|issn=0920-3796}}</ref>\n\nIn 1997, JET produced a peak of 16.1 MW of fusion power (65% of heat to plasma,<ref>[http://fusionforenergy.europa.eu/downloads/mediacorner/publications/reports/fusion_research_english.pdf FUSION RESEARCH An Energy Option for An Energy Option for Europe's Future ], pa. 27</ref>) with fusion power of over 10 MW sustained for over 0.5 sec.<ref>{{Cite book|last=Claessens|first=Michel|date=2020|title=ITER: The Giant Fusion Reactor|url=http://dx.doi.org/10.1007/978-3-030-27581-5|doi=10.1007/978-3-030-27581-5|isbn=978-3-030-27580-8|s2cid=243590344}}</ref>\n\n [[File:MAST plasma image.jpg|thumbnail|The [[Mega Ampere Spherical Tokamak]] became operational in the UK in 1999]]\n\n"Fast ignition"<ref>{{Cite book|last=Atzeni, Stefano|url=https://www.worldcat.org/oclc/56645784|title=The physics of inertial fusion : beam plasma interaction, hydrodynamics, hot dense matter|date=2004|publisher=Clarendon Press|others=Meyer-ter-Vehn, J\u00fcrgen|isbn=978-0-19-856264-1|location=Oxford|oclc=56645784}}</ref><ref>{{Cite book|last=Pfalzner|first=Susanne|url=http://dx.doi.org/10.1201/9781420011845|title=An Introduction to Inertial Confinement Fusion|date=2006-03-02|publisher=CRC Press|doi=10.1201/9781420011845|isbn=978-0-429-14815-6}}</ref> saved power and moved ICF into the race for energy production.\n\nIn 2006 China's [[EAST]] test reactor was completed.<ref>{{Cite web|title=People's Daily Online -- China to build world's first "artificial sun" experimental device|url=http://en.people.cn/200601/21/eng20060121_237208.html|access-date=2020-10-10|website=en.people.cn}}</ref> It was the first tokamak to use superconducting magnets to generate both toroidal and poloidal fields.\n\nIn March 2009, the laser-driven ICF [[National Ignition Facility|NIF]] became operational.<ref>[https://lasers.llnl.gov/about/what-is-nif What is NIF?] {{Webarchive|url=https://web.archive.org/web/20170731064919/https://lasers.llnl.gov/about/what-is-nif |date=July 31, 2017 }}, Lawrence Livermore National Laboratory.</ref>\n\nIn the 2000s privately backed fusion companies entered the race, including [[Tri Alpha Energy]],<ref>{{Cite news|url=https://www.forbes.com/sites/michaelkanellos/2013/03/11/hollywood-silicon-valley-and-russia-join-forces-on-nuclear-fusion/#12c2795972ba|title=Hollywood, Silicon Valley and Russia Join Forces on Nuclear Fusion|last=Kanellos|first=Michael|work=Forbes|access-date=2017-08-21|language=en}}</ref> [[General Fusion]],<ref name=":1">{{Cite web|last=Frochtzwajg|first=Jonathan|title=The secretive, billionaire-backed plans to harness fusion|url=http://www.bbc.com/future/story/20160428-the-secretive-billionaire-backed-plans-to-harness-fusion|access-date=2017-08-21|website=BBC}}</ref><ref name=":0">{{Cite journal|last=Clery|first=Daniel|date=2014-07-25|title=Fusion's restless pioneers|journal=Science|language=en|volume=345|issue=6195|pages=370\u2013375|bibcode=2014Sci...345..370C|doi=10.1126/science.345.6195.370|issn=0036-8075|pmid=25061186|ref=none}}</ref> and [[Tokamak Energy]].<ref>{{Cite web|url=http://www.bbc.com/future/story/20170418-the-made-in-chelsea-star-building-a-fusion-reactor|title=The British reality TV star building a fusion reactor|last=Gray|first=Richard|access-date=2017-08-21}}</ref>\n\n [[File:Preamplifier at the National Ignition Facility.jpg|upright=1.15|thumb|The preamplifiers of the National Ignition Facility. In 2012, the NIF achieved a 500-terawatt shot.]]\n[[File:Wendelstein7-X Torushall-2011.jpg|upright=1.15|thumb|The Wendelstein7X under construction]]\n[[File:W7X-Spulen Plasma blau gelb.jpg|thumb|upright=1.15|Example of a stellarator design: A coil system (blue) surrounds plasma (yellow). A magnetic field line is highlighted in green on the yellow plasma surface.]]\n\nPrivate and public research accelerated in the 2010s. General Fusion developed plasma injector technology and Tri Alpha Energy tested its C-2U device.<ref>{{Cite journal|last=Clery|first=Daniel|date=2017-04-28|title=Private fusion machines aim to beat massive global effort|journal=Science|language=en|volume=356|issue=6336|pages=360\u2013361|bibcode=2017Sci...356..360C|doi=10.1126/science.356.6336.360|issn=0036-8075|pmid=28450588|s2cid=206621512}}</ref> The French [[Laser M\u00e9gajoule]] began operation. NIF achieved net energy gain<ref>{{cite web |title=PW 2012: fusion laser on track for 2012 burn |publisher=Optics.org |author=SPIE Europe Ltd |url=http://optics.org/news/3/1/37 |access-date=2013-06-22}}</ref> in 2013, as defined in the very limited sense as the hot spot at the core of the collapsed target, rather than the whole target.<ref>{{cite news |url=https://www.bbc.co.uk/news/science-environment-24429621 |title=Nuclear fusion milestone passed at US lab |work=BBC News |access-date=30 October 2014}}</ref>\n\nIn 2014, [[Phoenix Nuclear Labs]] sold a high-yield neutron generator that could sustain 5\u00d710<sup>11</sup> [[deuterium]] fusion reactions per second over a 24-hour period.<ref>{{cite web|url=http://phoenixnuclearlabs.com/product/high-yield-neutron-generator/|title=The Alectryon High Yield Neutron Generator|year=2013|publisher=Phoenix Nuclear Labs}}</ref>\n\nIn 2015, [[MIT]] announced a [[tokamak]] it named the [[ARC fusion reactor]], using [[rare-earth barium-copper oxide]] (REBCO) superconducting tapes to produce high-magnetic field coils that it claimed could produce comparable magnetic field strength in a smaller configuration than other designs.<ref>{{cite news |last=Chandler |first=David L. |title=A small, modular, efficient fusion plant |work=MIT News |publisher=MIT News Office |url=http://newsoffice.mit.edu/2015/small-modular-efficient-fusion-plant-0810 |date=10 August 2015}}</ref> In October, researchers at the [[Max Planck Institute of Plasma Physics]] completed building the largest [[stellarator]] to date, the [[Wendelstein 7-X]]. It soon produced helium and hydrogen plasmas lasting up to 30 minutes.<ref>{{Cite web|last=Max Planck Institute for Experimental Physics|date=February 3, 2016|title=Wendelstein 7-X fusion device produces its first hydrogen plasma|url=https://www.ipp.mpg.de/4010154/02_16|url-status=live|access-date=2021-06-15|website=www.ipp.mpg.de|language=en}}</ref>\n\nIn 2017 [[Helion Energy]]'s fifth-generation plasma machine went into operation.<ref name=":2">{{Cite web|last=Wang|first=Brian|date=August 1, 2018|title=Nuclear Fusion Updated project reviews|url=https://www.nextbigfuture.com/2018/08/nuclear-fusion-updated-project-reviews.html|access-date=2018-08-03|website=www.nextbigfuture.com|language=en-US}}</ref> The UK's Tokamak Energy's [[Tokamak Energy|ST40]] generated "first plasma".<ref>{{Cite web|url=https://www.sciencealert.com/the-uk-has-just-switch-on-its-tokamak-nuclear-fusion-reactor|title=The UK Just Switched on an Ambitious Fusion Reactor - And It Works|last=MacDonald|first=Fiona|website=ScienceAlert|language=en-gb|access-date=2019-07-03}}</ref> The next year, [[Eni]] announced a $50 million investment in [[Commonwealth Fusion Systems]], to attempt to commercialize MIT's [[ARC fusion reactor|ARC]] technology.<ref>{{cite news |url=https://www.reuters.com/article/us-nuclearpower-fusion-eni/italys-eni-defies-skeptics-may-up-stake-in-nuclear-fusion-project-idUSKBN1HK1JJ |title=Italy's Eni defies sceptics, may up stake in nuclear fusion project |date=13 April 2018|newspaper=Reuters }}</ref><ref>{{cite web |url=https://www.seeker.com/energy/mit-aims-to-harness-fusion-power-within-15-years |title=MIT Aims to Harness Fusion Power Within 15 years |date=3 April 2018}}</ref><ref>{{cite web| url=http://www.wbur.org/bostonomix/2018/03/09/mit-nuclear-fusion |title=MIT Aims To Bring Nuclear Fusion To The Market In 10 Years |date=9 March 2018}}</ref><ref>{{cite web |url=https://news.mit.edu/2018/mit-newly-formed-company-launch-novel-approach-fusion-power-0309 |date=9 March 2018 |title= MIT and newly formed company launch novel approach to fusion power}}</ref>\n\n \nIn January, SuperOx announced the commercialization of a new [[superconducting wire]], with more than 700 A/mm2 current capability.<ref>{{cite journal |last1=Molodyk |first1=A. |last2=Samoilenkov |first2=S. |last3=Markelov |first3=A. |last4=Degtyarenko |first4=P. |last5=Lee |first5=S. |last6=Petrykin |first6=V. |last7=Gaifullin |first7=M. |last8=Mankevich |first8=A. |last9=Vavilov |first9=A. |last10=Sorbom |first10=B. |last11=Cheng |first11=J. |last12=Garberg |first12=S. |last13=Kesler |first13=L. |last14=Hartwig |first14=Z. |last15=Gavrilkin |first15=S. |last16=Tsvetkov |first16=A. |last17=Okada |first17=T. |last18=Awaji |first18=S. |last19=Abraimov |first19=D. |last20=Francis |first20=A. |last21=Bradford |first21=G. |last22=Larbalestier |first22=D. |last23=Senatore |first23=C. |last24=Bonura |first24=M. |last25=Pantoja |first25=A. E. |last26=Wimbush |first26=S. C. |last27=Strickland |first27=N. M. |last28=Vasiliev |first28=A. |title=Development and large volume production of extremely high current density YBa 2 Cu 3 O 7 superconducting wires for fusion |journal=Scientific Reports |date=22 January 2021 |volume=11 |issue=1 |pages=2084 |doi=10.1038/s41598-021-81559-z|pmid=33483553 |pmc=7822827 }}</ref>\n\nTAE Technologies announced results for its Norman device, holding a temperature of about 60 million \u00b0C (108 million \u00b0F) for 30 milliseconds, 8 and 10 times higher, respectively, than the company's previous devices.<ref>{{Cite web|last=Clery|first=Daniel|date=2021-04-08|title=With 'smoke ring' technology, fusion startup marks steady progress|url=https://www.sciencemag.org/news/2021/04/smoke-ring-technology-fusion-startup-marks-steady-progress|url-status=live|access-date=2021-04-11|website=Science {{!}} AAAS|language=en}}</ref>\n\nIn October, Oxford-based First Light Fusion revealed its projectile fusion project, which fires an aluminum disc at a fusion target, accelerated by a 9 mega-amp electrical pulse, reaching speeds of {{Convert|20|km/s}}. The resulting fusion generates neutrons whose energy is captured as heat.<ref>{{Cite news|last=Morris|first=Ben|date=2021-09-30|title=Clean energy from the fastest moving objects on earth|language=en-GB|work=BBC News|url=https://www.bbc.com/news/business-58602159|access-date=2021-12-09}}</ref>\n\nOn November 8, in an invited talk to the 63rd Annual Meeting of the APS Division of Plasma Physics,<ref>{{Cite web|url=https://meetings.aps.org/Meeting/DPP21/Session/AR01?showAbstract|title = Session AR01: Review: Creating A Burning Plasma on the National Ignition Facility}}</ref> the [[National Ignition Facility]] claimed <ref name="physics_v14_168">{{Cite web|url=https://physics.aps.org/articles/v14/168|title = Ignition First in a Fusion Reaction}}</ref> to have triggered [[fusion ignition]] in the laboratory on Sunday, August 8th 2021 for the first time in the 60+ year history of the ICF program.<ref>{{Cite web|url=https://phys.org/news/2021-08-major-nuclear-fusion-milestone-ignition.html|title = Major nuclear fusion milestone reached as 'ignition' triggered in a lab}}</ref><ref>{{Cite web|url=https://www.llnl.gov/news/national-ignition-facility-experiment-puts-researchers-threshold-fusion-ignition|title = National Ignition Facility experiment puts researchers at threshold of fusion ignition}}</ref>  The shot yield 1.3 Megajoules of fusion energy, an over 8X improvements on tests done in spring of 2021.<ref name="physics_v14_168" />  NIF estimates that 230 kilo-joules of energy reached the fuel capsule, which resulted in an almost 6-fold energy output from the capsule.<ref name="physics_v14_168" /> A researcher from Imperial College London stated that the majority of the field agreed that ignition had been demonstrated.<ref name="physics_v14_168" /> Researchers at NIF has since been trying to replicate the August result, so far without success.<ref>{{Cite journal|url=https://physicstoday.scitation.org/do/10.1063/PT.6.2.20211203a/full/|title = Lawrence Livermore's latest attempts at ignition fall short|doi = 10.1063/PT.6.2.20211203a|s2cid = 244935714}}</ref>\n\nIn November 2021, [[Helion Energy]] reported receiving $0.5 billion in Series E funding for its seventh-generation Polaris device, designed to demonstrate net electricity production, with an additional $1.7 billion of commitments tied to specific milestones,<ref>{{Cite web|last=Conca|first=James|title=Helion Energy Raises $500 Million On The Fusion Power Of Stars|url=https://www.forbes.com/sites/jamesconca/2021/11/09/helion-energy-raises-500-million-on-the-fusion-power-of-stars/|access-date=2021-12-19|website=Forbes|language=en}}</ref> while Commonwealth Fusion Systems raised an additional $1.8 billion in Series B funding to construct and operate its SPARC reactor, the single largest investment in any private fusion company.<ref>{{Cite news|last=Journal|first=Jennifer Hiller {{!}} Photographs by Tony Luong for The Wall Street|date=2021-12-01|title=WSJ News Exclusive {{!}} Nuclear-Fusion Startup Lands $1.8 Billion as Investors Chase Star Power|language=en-US|work=Wall Street Journal|url=https://www.wsj.com/articles/nuclear-fusion-startup-lands-1-8-billion-as-investors-chase-star-power-11638334801|access-date=2021-12-17|issn=0099-9660}}</ref>"}},
{"article_title": "Long March (rocket family)", "pageid": "55125", "revid": "1062545500", "timestamp": "2021-12-29T03:19:13Z", "history_paths": [["Long March (rocket family) --- Introduction ---", "History"]], "categories": ["long march (rocket family)", "rocket families", "space launch vehicles of china", "1970 in spaceflight", "1970 in china", "1970 in technology", "projects established in 1970", "chinese brands"], "heading_tree": {"Long March (rocket family) --- Introduction ---": {"History": {"Entry into commercial launch market": {}, "United States embargo on Chinese launches": {}, "Return to success": {}}, "Payloads": {}, "Propellants": {}, "Variants": {"Long March 8": {}, "Future development": {"Long March 9": {}, "921 rocket": {}}}, "Origins": {}, "Launch sites": {}, "Commercial launch services": {}, "Notes": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Long March (rocket family) --- Introduction ---|History": "{{Main list|List of Long March launches}}\nChina used the [[Long March 1]] rocket to launch its first [[satellite]], [[Dong Fang Hong I|Dong Fang Hong 1]] (lit. "The East is Red 1"), into [[low Earth orbit]] on 24 April 1970, becoming the fifth nation to achieve independent launch capability. Early launches had an inconsistent record, focusing on the launching of Chinese satellites. The [[Long March 1]] was quickly replaced by the [[Long March 2]] family of launchers.\n<gallery>\nFile:Changzheng-1 Rocket Model in Victoria Park, Hong Kong.jpg|Long March 1\nFile:Changzheng-1 Rocket Model in Victoria Park, Hong Kong (2).jpg|Long March 1 engine\n</gallery>\n\n [[File:Chang_zheng_3a_launch.png|thumb|200px|upright=1.2|right|[[Long March 3A]] launch]]\nAfter the [[Space Shuttle Challenger disaster|U.S. Space Shuttle ''Challenger'' was destroyed]] in 1986, a growing commercial backlog gave China the chance to enter the international launch market. In September 1988, [[President of the United States|U.S. President]] [[Ronald Reagan]] agreed to allow U.S satellites to be launched on Chinese rockets.<ref>{{cite news|last1=Stevenson|first1=Richard W.|title=Shaky Start for Rocket Business|url=https://www.nytimes.com/1988/09/16/business/shaky-start-for-rocket-business.html|newspaper=The New York Times|date=September 16, 1988|access-date=January 28, 2018|archive-url=https://web.archive.org/web/20171201055613/http://www.nytimes.com/1988/09/16/business/shaky-start-for-rocket-business.html|archive-date=December 1, 2017|url-status=live}}</ref> Reagan's satellite export policy would continue to 1998, through Bush and Clinton administrations, with 20 or more approvals.<ref name=":2">{{Cite web|title=Clinton Defends China Satellite Waiver - May 22, 1998|url=https://www.cnn.com/ALLPOLITICS/1998/05/22/china.money/|access-date=2021-12-13|website=www.cnn.com}}</ref> [[AsiaSat|AsiaSat 1]], which had originally been launched by the Space Shuttle and retrieved by another Space Shuttle after a failure, was launched by a [[Long March 3]] in 1990 as the first foreign payload on a Chinese rocket.\n\nHowever, major setbacks occurred in 1992\u20131996. The [[Long March 2E]] was designed with a defective payload fairing, which collapsed when faced with the rocket's excessive vibration. After just seven launches, the Long March 2E destroyed the [[Optus (satellite)#Optus B2|Optus B2]] and [[Apstar 2]] satellites and damaged [[AsiaSat 2]].<ref name="zinger2014">{{cite journal|last1=Zinger|first1=Kurtis J.|title=An Overreaction that Destroyed an Industry: The Past, Present, and Future of U.S. Satellite Export Controls|year=2014|url=http://lawreview.colorado.edu/wp-content/uploads/2015/07/13.-86.1-Zinger_Final.pdf|access-date=November 28, 2017|archive-url=https://web.archive.org/web/20171201042907/http://lawreview.colorado.edu/wp-content/uploads/2015/07/13.-86.1-Zinger_Final.pdf|archive-date=December 1, 2017|url-status=live}}</ref><ref name="globalsecurity">{{cite web|title=CZ-2E Space Launch Vehicle|url=https://www.globalsecurity.org/space/world/china/cz-2e.htm|website=globalsecurity.org|access-date=November 28, 2017|archive-url=https://web.archive.org/web/20171201080935/https://www.globalsecurity.org/space/world/china/cz-2e.htm|archive-date=December 1, 2017|url-status=live}}</ref> The [[Long March 3B]] also experienced a catastrophic failure in 1996, veering off course shortly after liftoff and crashing into a nearby village. At least 6 people were killed on the ground, and the [[Intelsat 708]] satellite was also destroyed.<ref name="ChenLan1">{{cite web|last1=Lan|first1=Chen|title=Mist around the CZ-3B disaster, part 1|url=http://www.thespacereview.com/article/2323/1|publisher=The Space Review|access-date=18 January 2014|archive-url=https://web.archive.org/web/20171201035826/http://www.thespacereview.com/article/2323/1|archive-date=December 1, 2017|url-status=live}}</ref> A [[Long March 3]] also experienced a partial failure in August 1996 during the launch of [[Chinasat|Chinasat-7]].<ref>{{Cite web|title=NASA - NSSDCA - Spacecraft - Details|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1996-048A|access-date=2021-12-15|website=nssdc.gsfc.nasa.gov}}</ref> Six Long March rockets ([[Long March 2C|Chang Zheng 2C/SD]]) launched 12 [[Iridium satellite constellation|Iridium satellites]], about a sixth of Iridium satellites in the original fleet.<ref>{{Cite web|last=Graham|first=William|date=2018-03-30|title=Iridium NEXT-5 satellites ride to orbit on SpaceX Falcon 9|url=https://www.nasaspaceflight.com/2018/03/iridium-next-5-satellites-spacex-falcon-9/|access-date=2021-12-15|website=NASASpaceFlight.com|language=en-US}}</ref>\n\n {{see also|International Traffic in Arms Regulations#Satellite components}}\n\nThe involvement of United States companies in the [[Apstar 2]] and [[Intelsat 708]] investigations caused great controversy in the United States. In the [[Cox Report]], the [[United States Congress]] accused [[SSL (company)|Space Systems/Loral]] and [[Hughes Aircraft Company]] of transferring information that would improve the design of Chinese rockets and ballistic missiles.<ref name="zenio2006">{{cite news |last1=Zelnio|first1=Ryan|title=A short history of export control policy|url=http://www.thespacereview.com/article/528/1|publisher=The Space Review|date=January 9, 2006|access-date=November 28, 2017|archive-url=https://web.archive.org/web/20171211160307/http://www.thespacereview.com/article/528/1|archive-date=December 11, 2017|url-status=live}}</ref> Although the Long March was allowed to launch its commercial backlog, the [[United States Department of State]] has not approved any satellite export licenses to China since 1998. [[Chinasat|ChinaSat 8]], which had been scheduled for launch in April 1999 on a [[Long March 3B]] rocket,<ref>{{cite journal|author1=Associate Administrator for Commercial Space Transportation, Federal Aviation Administration|title=Commercial Space Transportation Quarterly Launch Report |year=1999|url=https://www.faa.gov/about/office_org/headquarters_offices/ast/media/quarter9902.pdf|access-date=November 28, 2017|archive-url=https://web.archive.org/web/20170504212503/https://www.faa.gov/about/office_org/headquarters_offices/ast/media/quarter9902.pdf|archive-date=May 4, 2017|url-status=live}} {{PD-notice}}</ref> was placed in storage, sold to the Singapore company [[ProtoStar]], and finally launched on a European rocket [[Ariane 5]] in 2008.<ref name="zenio2006"/>\n\nFrom 2005 to 2012, Long March rockets launched ITAR-free satellites made by the European company [[Thales Alenia Space]].<ref>{{cite book|last1=Harvey|first1=Brian|title=China in Space: The Great Leap Forward |url=https://archive.org/details/chinaspacegreatl00harv|url-access=limited|year=2013|publisher=Springer|location=New York|isbn=9781461450436|pages=[https://archive.org/details/chinaspacegreatl00harv/page/n172 160]\u2013162}}</ref> However, Thales Alenia was forced to discontinue its ITAR-free satellite line in 2013 after the United States State Department fined a United States company for selling ITAR components.<ref>{{cite news|last1=Ferster|first1=Warren|title=U.S. Satellite Component Maker Fined US$8 Million for ITAR Violations|url=http://spacenews.com/37071us-satellite-component-maker-fined-8-million-for-itar-violations/|publisher=SpaceNews|date=5 September 2013}}</ref> [[Thales Alenia Space]] had long complained that "every satellite nut and bolt" was being ITAR-restricted, and the [[European Space Agency]] (ESA) accused the [[United States]] of using ITAR to block exports to China instead of protecting technology.<ref>{{cite news|last1=de Selding|first1=Peter B.|title=Thales Alenia Space: U.S. Suppliers at Fault in "ITAR-free" Misnomer|url=http://spacenews.com/36706thales-alenia-space-us-suppliers-at-fault-in-itar-free-misnomer/|publisher=SpaceNews|date=9 August 2013}}</ref> In 2016, an official at the [[Bureau of Industry and Security|United States Bureau of Industry and Security]] confirmed that "no U.S.-origin content, regardless of significance, regardless of whether it is incorporated into a foreign-made item, can go to China". The European aerospace industry is working on developing replacements for United States satellite components.<ref name="selding2016">{{cite news|last1=de Selding|first1=Peter B.|title=U.S. ITAR satellite export regime's effects still strong in Europe|url=http://spacenews.com/u-s-itar-satellite-export-regimes-effects-still-strong-in-europe/|publisher=SpaceNews|date=April 14, 2016}}</ref>\n\n After the failures of 1992\u20131996, the troublesome Long March 2E was withdrawn from the market. Design changes were made to improve the reliability of Long March rockets. From October 1996 to April 2009, the Long March rocket family delivered 75 consecutive successful launches, including several major milestones in space flight:\n* On 15 October 2003, the [[Long March 2F]] rocket successfully launched the ''[[Shenzhou 5]]'' spacecraft, carrying China's first astronaut into space. [[China]] became the third nation with independent [[human spaceflight]] capability, after the [[Soviet Union]]/[[Russia]] and the [[United States]]. \n* On 1 June 2007, Long March rockets completed their 100th launch overall. \n* On 24 October 2007, the [[Long March 3A]] successfully launched (10:05 [[Coordinated Universal Time|UTC]]) the "[[Chang'e 1]]" [[Moon|lunar]] orbiting [[spacecraft]] from the [[Xichang Satellite Launch Center]].\n\nThe Long March rockets have subsequently maintained an excellent reliability record. Since 2010, Long March launches have made up 15\u201325% of all space launches globally. Growing domestic demand has maintained a healthy manifest. International deals have been secured through a package deal that [[Product bundling|bundles]] the launch with a Chinese satellite, circumventing the United States embargo.<ref>{{cite news |last1=Henry|first1=Caleb|title=Back-to-back commercial satellite wins leave China Great Wall hungry for more|url=http://spacenews.com/back-to-back-commercial-satellite-wins-leave-china-great-wall-hungry-for-more/|publisher=SpaceNews|date=August 22, 2017}}</ref>"}},
{"article_title": "Drive letter assignment", "pageid": "55424", "revid": "1058127427", "timestamp": "2021-12-01T16:54:59Z", "history_paths": [["Drive letter assignment --- Introduction ---", "Origin"]], "categories": ["windows architecture", "dos technology", "computer peripherals", "assignment operations"], "heading_tree": {"Drive letter assignment --- Introduction ---": {"Origin": {}, "Operating systems that use drive letter assignment": {}, "Order of assignment": {}, "{{anchor|Memory drive}}Common assignments": {}, "{{anchor|Floating drive|Load drive}}ASSIGN, JOIN and SUBST in DOS and Windows": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Drive letter assignment --- Introduction ---|Origin": "The concept of drive letters, as used today, presumably{{citation needed|date=August 2016}} owes its origins to [[IBM]]'s [[VM (operating system)|VM]] family of operating systems, dating back to [[CP/CMS]] in 1967 (and its research predecessor [[CP-40]]), by way of [[Digital Research]]'s (DRI) [[CP/M]]. The concept evolved through several steps:\n\n* CP/CMS uses drive letters to identify ''[[minidisk (CP/CMS)|minidisk]]s'' attached to a user session.<ref name="ducharme"/> A full file reference (''pathname'' in today's parlance) consists of a ''filename'', a ''filetype'', and a disk letter called a ''filemode'' (e.g. '''A''' or '''B'''). Minidisks can correspond to physical disk drives, but more typically refer to logical drives, which are mapped automatically onto shared devices by the operating system as sets of ''virtual cylinders''.\n* CP/CMS inspired numerous other operating systems, including the CP/M microcomputer operating system, which uses a drive letter to specify a physical storage device. Early versions of CP/M (and other microcomputer operating systems) implemented a [[flat file system]] on each disk drive, where a complete file reference consists of a ''drive letter'', a colon, a ''filename'' (up to [[8.3 filename|eight characters]]) and a ''[[Filename extension|filetype]]'' (three characters); for instance <code>A:README.TXT</code>. (This was the era of [[8-inch floppy disk]]s, where such small namespaces did not impose practical constraints.)  This usage was influenced by the device prefixes used in [[Digital Equipment Corporation]]'s (DEC) [[TOPS-10]] operating system.<ref name="johnson"/>\n* The drive letter syntax chosen for CP/M was inherited by [[Microsoft]] for its operating system [[MS-DOS]] by way of [[Seattle Computer Products]]' (SCP) [[86-DOS]], and thus also by IBM's OEM version [[PC DOS]]. Originally, drive letters always represented physical volumes, but support for [[logical volume]]s eventually appeared.\n* Through their designated position as DOS successor, the concept of drive letters was also inherited by [[OS/2]] and the [[Microsoft Windows]] family.\n\nThe important capability of [[file directory|hierarchical directories]] within each drive letter was initially absent from these systems. This was a major feature of [[UNIX]] and other similar operating systems, where hard disk drives held thousands (rather than tens or hundreds) of files. Increasing microcomputer storage capacities led to their introduction, eventually followed by [[long filename]]s. In file systems lacking such naming mechanisms, drive letter assignment proved a useful, simple organizing principle."}},
{"article_title": "Security-Enhanced Linux", "pageid": "55908", "revid": "1059632826", "timestamp": "2021-12-10T16:52:30Z", "history_paths": [["Security-Enhanced Linux --- Introduction ---", "History"]], "categories": ["linux kernel features", "linux security software", "national security agency", "red hat software", "unix file system technology"], "heading_tree": {"Security-Enhanced Linux --- Introduction ---": {"Overview": {}, "History": {"Original and external contributors": {}}, "Users, policies and security contexts": {}, "{{Anchor|AVC}}Features": {}, "Implementations": {}, "Use scenarios": {"Examples": {}}, "Comparison with AppArmor": {}, "Similar systems": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Security-Enhanced Linux --- Introduction ---|History": "The earliest work directed toward standardizing an approach providing mandatory and discretionary access controls (MAC and DAC) within a UNIX (more precisely, POSIX) computing environment can be attributed to the [[National Security Agency]]'s Trusted UNIX (TRUSIX) Working Group, which met from 1987 to 1991 and published one [[Rainbow Series|Rainbow Book]] (#020A), and produced a formal model and associated evaluation evidence prototype (#020B) that was ultimately unpublished.\n\nSELinux was designed to demonstrate the value of mandatory access controls to the Linux community and how such controls could be added to Linux. Originally, the patches that make up SELinux had to be explicitly applied to the Linux kernel source; SELinux was merged into the [[Linux kernel mainline]] in the 2.6 series of the Linux kernel.\n\nThe NSA, the original primary developer of SELinux, released the first version to the [[Open-source software|open source]] development community under the [[GNU GPL]] on December 22, 2000.<ref>Compare {{cite web\n | url        = https://www.nsa.gov/news-features/press-room/press-releases/2001/se-linux.shtml\n | archive-url = https://web.archive.org/web/20180918025937/https://www.nsa.gov/news-features/press-room/press-releases/2001/se-linux.shtml\n | archive-date = 2018-09-18\n | title      = National Security Agency Shares Security Enhancements to Linux\n | date       = 2001-01-02\n | work       = NSA Press Release\n | publisher  = National Security Agency Central Security Service\n | location   = Fort George G. Meade, Maryland\n | access-date = 2021-04-21\n | quote      = The NSA is pleased to announce that it has developed, and is making available to the public, a prototype version of a security-enhanced Linux operating system.}}</ref> The software was merged into the mainline Linux kernel 2.6.0-test3, released on 8 August 2003. Other significant contributors include [[Red Hat]], [[Network Associates]], [[Secure Computing Corporation]], Tresys Technology, and Trusted Computer Solutions. Experimental ports of the [[FLASK]]/TE implementation have been made available via the [[TrustedBSD]] Project for the [[FreeBSD]] and [[Darwin (operating system)|Darwin]] operating systems.\n\nSecurity-Enhanced Linux implements the [[FLASK|Flux Advanced Security Kernel]] (FLASK). Such a kernel contains architectural components prototyped in the [[Fluke operating system]]. These provide general support for enforcing many kinds of mandatory access control policies, including those based on the concepts of [[type enforcement]], [[role-based access control]], and [[multilevel security]]. FLASK, in turn, was based on DTOS, a Mach-derived [[Distributed Trusted Operating System]], as well as on Trusted Mach, a research project from [[Trusted Information Systems]] that had an influence on the design and implementation of DTOS.\n\n \nA comprehensive list of the original and external contributors to SELinux was hosted at the NSA website until maintenance ceased, sometime 2009. The following list reproduces the original as [https://web.archive.org/web/20081018034429/http://www.nsa.gov/selinux/info/contrib.cfm preserved] by the Internet Archive Wayback Machine. The scope of their contributions was listed in the page and has been omitted for brevity, but it can be accessed through the archived copy.<ref>{{cite web |title=Contributors to SELinux |url=http://www.nsa.gov/selinux/info/contrib.cfm|archive-url=https://web.archive.org/web/20081018034429/http://www.nsa.gov/selinux/info/contrib.cfm|archive-date=2008-10-18}}</ref>\n\n{{columns-list|colwidth=35em|\n* [[National Security Agency|The National Security Agency]] (NSA)\n* [[Network Associates Laboratories]] (NAI Labs)\n* [[Mitre Corporation|The MITRE Corporation]]\n* [[Secure Computing Corporation]] (SCC)\n* Matt Anderson\n* Ryan Bergauer\n* Bastian Blank\n* Thomas Bleher\n* Joshua Brindle\n* Russell Coker\n* John Dennis\n* Janak Desai\n* Ulrich Drepper\n* Lorenzo Hernandez Garcia-Hierro\n* Darrel Goeddel\n* Carsten Grohmann\n* Steve Grubb\n* Ivan Gyurdiev\n* Serge Hallyn\n* Chad Hanson\n* Joerg Hoh\n* Trent Jaeger\n* Dustin Kirkland\n* Kaigai Kohei\n* Paul Krumviede\n* Joy Latten\n* Tom London\n* Karl MacMillan\n* Brian May\n* Frank Mayer\n* Todd Miller\n* Roland McGrath\n* Paul Moore\n* James Morris\n* Yuichi Nakamura\n* Greg Norris\n* Eric Paris\n* Chris PeBenito\n* [[Red Hat]]\n* Petre Rodan\n* Shaun Savage\n* Chad Sellers\n* Rogelio Serrano Jr.\n* Justin Smith\n* Manoj Srivastava\n* Tresys Technology\n* Michael Thompson\n* Trusted Computer Solutions\n* Tom Vogt\n* Reino Wallin\n* Dan Walsh\n* Colin Walters\n* Mark Westerman\n* David A. Wheeler\n* Venkat Yekkirala\n* Catherine Zhang\n}}"}},
{"article_title": "Interlaced video", "pageid": "56189", "revid": "1056180931", "timestamp": "2021-11-20T07:18:41Z", "history_paths": [["Interlaced video --- Introduction ---", "History"]], "categories": ["film and video technology", "television technology", "video formats", "1925 introductions"], "heading_tree": {"Interlaced video --- Introduction ---": {"Description": {}, "Benefits of interlacing": {}, "Interlacing problems": {"Interline twitter": {}}, "Deinterlacing": {}, "History": {"Interlace and computers": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Interlaced video --- Introduction ---|History": "When motion picture film was developed, the movie screen had to be illuminated at a high rate to prevent visible [[flicker (screen)|flicker]]. The exact rate necessary varies by brightness \u2014 50 Hz is (barely) acceptable for small, low brightness displays in dimly lit rooms, whilst 80 Hz or more may be necessary for bright displays that extend into peripheral vision. The film solution was to project each frame of film three times using a three-bladed shutter: a movie shot at 16 frames per second illuminated the screen 48 times per second. Later, when sound film became available, the higher projection speed of 24 frames per second enabled a two bladed shutter to produce 48 times per second illumination\u2014but only in projectors incapable of projecting at the lower speed.\n\nThis solution could not be used for television. To store a full video frame and display it twice requires a [[frame buffer]]\u2014electronic memory ([[Random-access memory|RAM]])\u2014sufficient to store a video frame. This method did not become feasible until the late 1980s and with digital technology. In addition, avoiding on-screen [[interference (wave propagation)|interference patterns]] caused by studio lighting and the limits of [[vacuum tube]] technology required that CRTs for TV be scanned at [[Alternating current|AC]] line frequency. (This was 60 Hz in the US, 50 Hz Europe.)\n\nIn the domain of [[mechanical television]], [[L\u00e9on Theremin]] demonstrated the concept of interlacing. He had been developing a mirror drum-based television, starting with 16 lines resolution in 1925, then 32 lines and eventually 64 using interlacing in 1926. As part of his thesis, on May 7, 1926, he electrically transmitted and projected near-simultaneous moving images on a five-foot square screen.<ref name="glinsky">{{cite book| last = Glinsky| first = Albert| title = Theremin: Ether Music and Espionage| location = Urbana, Illinois| publisher = University of Illinois Press| year = 2000| isbn = 0-252-02582-2| url-access = registration| url = https://archive.org/details/thereminethermus00glin}} pages 41-45</ref>\n\nIn 1930, German [[Telefunken]] [[engineer]] [[Fritz Schr\u00f6ter]] first formulated and patented the concept of breaking a single video frame into interlaced lines.<ref>Registered by the German Reich patent office, patent no. 574085.</ref> In the USA, [[RCA]] engineer [[Randall C. Ballard]] patented the same idea in 1932.<ref name="Ballard">{{cite web|url=http://www.davidsarnoff.org/kil-chapter09.htm |title=Pioneering in Electronics |access-date=2006-07-27 |work=David Sarnoff Collection |archive-url=https://web.archive.org/web/20060821005430/http://www.davidsarnoff.org/kil-chapter09.htm |archive-date=2006-08-21 |url-status=dead }}</ref><ref>[http://www.google.com/patents?id=H49TAAAAEBAJ&dq=patent:2152234 U.S. patent 2,152,234]. Reducing flicker is listed only fourth in a list of objectives of the invention.</ref> Commercial implementation began in 1934 as cathode ray tube screens became brighter, increasing the level of flicker caused by [[progressive scan|progressive]] (sequential) scanning.<ref>R.W. Burns, ''Television: An International History of the Formative Years'', IET, 1998, p. 425. {{ISBN|978-0-85296-914-4}}.</ref>\n\nIn 1936, when the UK was setting analog standards, early [[vacuum tube|thermionic valve]] based CRT drive electronics could only scan at around 200 lines in 1/50 of a second (i.e. approximately a 10kHz repetition rate for the sawtooth horizontal deflection waveform). Using interlace, a pair of 202.5-line fields could be superimposed to become a sharper [[405 line]] frame (with around 377 used for the actual image, and yet fewer visible within the screen bezel; in modern parlance, the standard would be "377i"). The vertical scan frequency remained 50 Hz, but visible detail was noticeably improved. As a result, this system supplanted [[John Logie Baird]]'s 240 line mechanical progressive scan system that was also being trialled at the time.\n\nFrom the 1940s onward, improvements in technology allowed the US and the rest of Europe to adopt systems using progressively higher line-scan frequencies and more radio signal bandwidth to produce higher line counts at the same frame rate, thus achieving better picture quality. However the fundamentals of interlaced scanning were at the heart of all of these systems. The US adopted the [[480i|525 line]] system, later incorporating the composite color standard known as [[NTSC]], Europe adopted the [[576i|625 line]] system, and the UK switched from its idiosyncratic 405 line system to (the much more US-like) 625 to avoid having to develop a (wholly) unique method of color TV. France switched from its similarly unique 819 line monochrome system to the more European standard of 625. Europe in general, including the UK, then adopted the [[PAL]] color encoding standard, which was essentially based on NTSC, but inverted the color carrier phase with each line (and frame) in order to cancel out the hue-distorting phase shifts that dogged NTSC broadcasts. France instead adopted its own unique, twin-FM-carrier based [[SECAM]] system, which offered improved quality at the cost of greater electronic complexity, and was also used by some other countries, notably Russia and its satellite states. Though the color standards are often used as synonyms for the underlying video standard - NTSC for 525i/60, PAL/SECAM for 625i/50 - there are several cases of inversions or other modifications; e.g. PAL color is used on otherwise "NTSC" (that is, 525i/60) broadcasts in Brazil, as well as vice versa elsewhere, along with cases of PAL bandwidth being squeezed to 3.58MHz to fit in the broadcast waveband allocation of NTSC, or NTSC being expanded to take up PAL's 4.43MHz.\n\nInterlacing was ubiquitous in displays until the 1970s, when the needs of [[computer monitor]]s resulted in the reintroduction of progressive scan, including on regular TVs or simple monitors based on the same circuitry; most CRT based displays are entirely capable of displaying both progressive and interlace regardless of their original intended use, so long as the horizontal and vertical frequencies match, as the technical difference is simply that of either starting/ending the vertical sync cycle halfway along a scanline every other frame (interlace), or always synchronising right at the start/end of a line (progressive). Interlace is still used for most standard definition TVs, and the [[1080i]] [[High-definition television|HDTV]] broadcast standard, but not for [[Liquid crystal display|LCD]], micromirror ([[Digital Light Processing|DLP]]), or most [[plasma display]]s; these displays do not use a [[raster scan]] to create an image (their panels may still be updated in a left-to-right, top-to-bottom scanning fashion, but always in a progressive fashion, and not necessarily at the same rate as the input signal), and so cannot benefit from interlacing (where older LCDs use a "dual scan" system to provide higher resolution with slower-updating technology, the panel is instead divided into two ''adjacent'' halves that are updated ''simultaneously''): in practice, they have to be driven with a progressive scan signal. The [[deinterlacing]] circuitry to get progressive scan from a normal interlaced broadcast television signal can add to the cost of a television set using such displays. Currently, progressive displays dominate the HDTV market.\n\n In the 1970s, computers and home video game systems began using TV sets as display devices.  At that point, a 480-line [[NTSC]] signal was well beyond the graphics abilities of low cost computers, so these systems used a simplified video signal that made each video field scan directly on top of the previous one, rather than each line between two lines of the previous field, along with relatively low horizontal pixel counts. This marked the return of [[progressive scan]]ning not seen since the 1920s. Since each field became a complete frame on its own, modern terminology would call this [[240p]] on NTSC sets, and [[288p]] on [[PAL]].  While consumer devices were permitted to create such signals, broadcast regulations prohibited TV stations from transmitting video like this. Computer monitor standards such as the TTL-RGB mode available on the [[Color Graphics Adapter|CGA]] and e.g. [[BBC Micro]] were further simplifications to NTSC, which improved picture quality by omitting modulation of color, and allowing a more direct connection between the computer's graphics system and the CRT.\n\nBy the mid-1980s, computers had outgrown these video systems and needed better displays. Most home and basic office computers suffered from the use of the old scanning method, with the highest display resolution being around 640x200 (or sometimes 640x256 in 625-line/50\u00a0Hz regions), resulting in a severely distorted tall narrow [[pixel]] shape, making the display of high resolution text alongside realistic proportioned images difficult (logical "square pixel" modes were possible but only at low resolutions of 320x200 or less). Solutions from various companies varied widely.  Because PC monitor signals did not need to be broadcast, they could consume far more than the 6, 7 and 8 [[Hertz|MHz]] of bandwidth that NTSC and PAL signals were confined to. IBM's [[Monochrome Display Adapter]] and [[Enhanced Graphics Adapter]] as well as the [[Hercules Graphics Card]] and the original [[Apple Macintosh|Macintosh]] computer generated video signals of 342 to 350p, at 50 to 60\u00a0Hz, with approximately 16MHz of bandwidth, some enhanced [[PC clone]]s such as the [[AT&T 6300]] (aka Olivetti M24) as well as computers made for the Japanese home market managed 400p instead at around 24MHz, and the [[Atari ST]] pushed that to 71Hz with 32MHz bandwidth - all of which required dedicated high-frequency (and usually single-mode, i.e. not "video"-compatible) monitors due to their increased line rates. The [[Amiga|Commodore Amiga]] instead created a true interlaced 480i60/576i50 [[RGB color model|RGB]] signal at broadcast video rates (and with a 7 or 14MHz bandwidth), suitable for NTSC/PAL encoding (where it was smoothly decimated to 3.5~4.5MHz). This ability (plus built-in [[genlocking]]) resulted in the Amiga dominating the video production field until the mid-1990s, but the interlaced display mode caused flicker problems for more traditional PC applications where single-pixel detail is required, with "flicker-fixer" scan-doubler peripherals plus high-frequency RGB monitors (or Commodore's own specialist scan-conversion A2024 monitor) being popular, if expensive, purchases amongst power users. 1987 saw the introduction of [[Video Graphics Array|VGA]], on which PCs soon standardized, as well as Apple's [[Macintosh II]] range which offered displays of similar, then superior resolution and color depth, with rivalry between the two standards (and later PC quasi-standards such as XGA and SVGA) rapidly pushing up the quality of display available to both professional and home users.\n\nIn the late 1980s and early 1990s, monitor and graphics card manufacturers introduced newer high resolution standards that once again included interlace.  These monitors ran at higher scanning frequencies, typically allowing a 75 to 90\u00a0Hz field rate (i.e. 37 to 45Hz frame rate), and tended to use longer-persistence phosphors in their CRTs, all of which was intended to alleviate flicker and shimmer problems. Such monitors proved generally unpopular, outside of specialist ultra-high-resolution applications such as [[Computer Aided Design|CAD]] and [[Desktop Publishing|DTP]] which demanded as many pixels as possible, with interlace being a necessary evil and better than trying to use the progressive-scan equivalents. Whilst flicker was often not immediately obvious on these displays, eyestrain and lack of focus nevertheless became a serious problem, and the trade-off for a longer afterglow was reduced brightness and poor response to moving images, leaving visible and often off-colored trails behind. These colored trails were a minor annoyance for monochrome displays, and the generally slower-updating screens used for design or database-query purposes, but much more troublesome for color displays and the faster motions inherent in the increasingly popular window-based operating systems, as well as the full-screen scrolling in WYSIWYG word-processors, spreadsheets, and of course for high-action games. Additionally, the regular, thin horizontal lines common to early GUIs, combined with low color depth that meant window elements were generally high-contrast (indeed, frequently stark black-and-white), made shimmer even more obvious than with otherwise lower fieldrate video applications. As rapid technological advancement made it practical and affordable, barely a decade after the first ultra-high-resolution interlaced upgrades appeared for the IBM PC, to provide sufficiently high pixel clocks and horizontal scan rates for hi-rez progressive-scan modes in first professional and then consumer-grade displays, the practice was soon abandoned. For the rest of the 1990s, monitors and graphics cards instead made great play of their highest stated resolutions being "non-interlaced", even where the overall framerate was barely any higher than what it had been for the interlaced modes (e.g. SVGA at 56p versus 43i to 47i), and usually including a top mode technically exceeding the CRT's actual resolution (number of color-phosphor triads) which meant there was no additional image clarity to be gained through interlacing and/or increasing the signal bandwidth still further. This experience is why the PC industry today remains against interlace in HDTV, and lobbied for the 720p standard, and continues to push for the adoption of 1080p (at 60\u00a0Hz for NTSC legacy countries, and 50\u00a0Hz for PAL); however, 1080i remains the most common HD broadcast resolution, if only for reasons of backward compatibility with older HDTV hardware that cannot support 1080p - and sometimes not even 720p - without the addition of an external scaler, similar to how and why most SD-focussed digital broadcasting still relies on the otherwise obsolete [[MPEG2]] standard embedded into e.g. [[DVB-T]]."}},
{"article_title": "Dialysis", "pageid": "56511", "revid": "1057277552", "timestamp": "2021-11-26T16:23:19Z", "history_paths": [["Dialysis --- Introduction ---", "History"]], "categories": ["renal dialysis", "detoxification", "medical mnemonics", "membrane technology"], "heading_tree": {"Dialysis --- Introduction ---": {"Background": {}, "Principle": {}, "Types": {"Hemodialysis": {}, "Peritoneal dialysis": {}, "Hemofiltration": {}, "Hemodiafiltration": {}, "Intestinal dialysis": {}}, "Indications": {"Acute indications": {}, "Chronic indications": {}}, "Dialyzable substances": {"Characteristics": {}, "Substances": {}}, "Pediatric dialysis": {}, "Dialysis in different countries": {"In the United Kingdom": {}, "In the United States": {}, "In China": {}}, "History": {}, "See also": {"Materials and methods": {}, "Medical applications": {}}, "References": {}, "Bibliography": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Dialysis --- Introduction ---|History": "[[File:Dialysis - arm - 01.jpg|thumb|right|150px|Arm hooked up to dialysis tubing.]]\nIn 1913, [[Leonard Rowntree]] and John Abel of [[Johns Hopkins Hospital]] developed the first dialysis system which they successfully tested in animals.<ref>{{cite journal |last1=ABEL |first1=J. J. |last2=ROWNTREE |first2=L. G. |last3=TURNER |first3=B. B. |title=On the removal of diffusible substances from the circulating blood by means of dialysis. |journal=Trans Assoc Am Phys |date=1913 |volume=28 |pages=51\u201354}}</ref> A Dutch doctor, [[Willem Johan Kolff]], constructed the first working dialyzer in 1943 during the [[History of the Netherlands (1939\u20131945)|Nazi occupation of the Netherlands]].<ref name=NYT>{{Cite news|title=Willem Kolff, Doctor Who Invented Kidney and Heart Machines, Dies at 97| url=https://www.nytimes.com/2009/02/13/health/13kolff.html?pagewanted=all|date=12 February 2009| newspaper=The New York Times| last1=Blakeslee| first1=Sandra}}</ref> Due to the scarcity of available resources, Kolff had to improvise and build the initial machine using [[Casing (sausage)|sausage casings]], [[beverage can]]s, a [[washing machine]] and various other items that were available at the time. Over the following two years (1944\u20131945), Kolff used his machine to treat 16 patients suffering from [[acute kidney failure]], but the results were unsuccessful. Then, in 1945, a 67-year-old comatose woman regained consciousness following 11 hours of hemodialysis with the dialyzer and lived for another seven years before dying from an unrelated condition. She was the first-ever patient successfully treated with dialysis.<ref name="NYT"/> [[Donald Walter Gordon Murray|Gordon Murray]] of the [[University of Toronto]] independently developed a dialysis machine in 1945. Unlike Kolff's rotating drum, Murray's machine used fixed flat plates, more like modern designs.<ref>{{cite journal |last1=McAlister |first1=VC |title=Clinical kidney transplantation: a 50th anniversary review of the first reported series. |journal=American Journal of Surgery |date=September 2005 |volume=190 |issue=3 |pages=485\u20138 |doi=10.1016/j.amjsurg.2005.04.016 |pmid=16105541|url=http://ir.lib.uwo.ca/cgi/viewcontent.cgi?article=1052&context=surgerypub }}</ref> Like Kolff, Murray's initial success was in patients with acute renal failure.<ref>{{cite journal |last1=MURRAY |first1=G |last2=DELORME |first2=E |last3=THOMAS |first3=N |title=Development of an artificial kidney; experimental and clinical experiences. |journal=Archives of Surgery |date=November 1947 |volume=55 |issue=5 |pages=505\u201322 |pmid=20271745|doi=10.1001/archsurg.1947.01230080514001 }}</ref> [[Nils Alwall]] of [[Lund University]] in Sweden modified a similar construction to the Kolff dialysis machine by enclosing it inside a stainless steel canister. This allowed the removal of fluids, by applying a negative pressure to the outside canister, thus making it the first truly practical device for hemodialysis. Alwall treated his first patient in acute kidney failure on 3 September 1946.<ref>{{Cite journal|last1=Kurkus|first1=Jan|last2=Ostrowski|first2=Janusz|date=7 August 2019|title=Nils Alwall and his artificial kidneys: Seventieth anniversary of the start of serial production|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/aor.13545|journal=Artificial Organs|language=en|volume=43|issue=8|pages=713\u2013718|doi=10.1111/aor.13545|pmid=31389617|s2cid=199467973|issn=0160-564X}}</ref>"}},
{"article_title": "Monocoque", "pageid": "57992", "revid": "1038285003", "timestamp": "2021-08-11T16:35:10Z", "history_paths": [["Monocoque --- Introduction ---", "Aircraft"]], "categories": ["automotive chassis types", "motorcycle frames", "airship technology", "structural engineering", "aircraft components"], "heading_tree": {"Monocoque --- Introduction ---": {"Aircraft": {}, "Vehicles": {"Race cars": {}, "Road cars": {}, "Armoured vehicles": {}, "Two-wheeled vehicles": {}}, "Rockets": {}, "See also": {}, "References": {"Citations": {}, "Bibliography": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Monocoque --- Introduction ---|Aircraft": "[[File:LFG Roland C.II LRQ.jpg|thumb|LFG Roland C.II with wooden ''Wickelrumpf'' monocoque fuselage]]\n[[File:Zeppelin-Lindau (Do) D.I.jpg|thumb|Zeppelin D.I, the first production all-metal monocoque aircraft]]\nEarly aircraft were constructed using frames, typically of [[wood]] or [[steel]] tubing, which could then be covered (or ''skinned'') with fabric<ref>Megson, 1972, p.198</ref> such as [[Irish linen]] or [[cotton]].<ref name="WWI Brit">Robertson, 1996, pp.1\u20132</ref> The fabric made a minor structural contribution in tension but none in compression and was there for aerodynamic reasons only. By considering the structure as a whole and not just the sum of its parts, monocoque construction integrated the skin and frame into a single load-bearing shell with significant improvements to strength and weight.\n\nTo make the shell, thin strips of wood were laminated into a three dimensional shape; a technique adopted from boat hull construction. One of the earliest examples was the [[Deperdussin Monocoque]] racer in 1912, which used a laminated fuselage made up of three layers of glued poplar veneer, which provided both the external skin and the main load-bearing structure.<ref name="ReferenceA">Aeronautics, 1912, p.112</ref> This also produced a smoother surface and reduced drag so effectively that it was able to win most of the races it was entered into.<ref name="ReferenceA"/>\n\nThis style of construction was further developed in Germany by [[Luft-Fahrzeug-Gesellschaft|LFG Roland]] using the patented ''Wickelrumpf'' (wrapped body) form later licensed by them to [[Pfalz Flugzeugwerke]] who used it on several fighter aircraft.  Each half of the fuselage shell was formed over a male mold using two layers of plywood strips with fabric wrapping between them. The early plywood used was prone to damage from moisture and delamination.<ref>FAA, 2001, p.1.2</ref>\n\nWhile all-metal aircraft such as the [[Junkers J 1]] had appeared as early as 1915, these were not monocoques but added a metal skin to an underlying framework.\n\nThe first metal monocoques were built by [[Claudius Dornier]], while working for Zeppelin-Lindau.<ref name="Terry, 1981, pp.97\u2013117">Terry, 1981, pp.97\u2013117</ref> He had to overcome a number of problems, not least was the quality of aluminium alloys strong enough to use as structural materials, which frequently formed layers instead of presenting a uniform material.<ref name="Terry, 1981, pp.97\u2013117"/> After failed attempts with several large flying boats in which a few components were monocoques, he built the [[Zeppelin-Lindau V1]] to test out a monocoque fuselage. Although it crashed, he learned a lot from its construction. The [[Dornier-Zeppelin D.I]] was built in 1918 and although too late for operational service during the war was the first all metal monocoque aircraft to enter production.<ref name="Terry, 1981, pp.97\u2013117"/><ref>Grosz, 1998</ref>\n\nIn parallel to Dornier, Zeppelin also employed [[Rohrbach Metall-Flugzeugbau|Adolf Rohrbach]], who built the [[Zeppelin-Staaken E-4/20]], which when it flew in 1920<ref>Haddow, Grosz, 1988 pp. 289\u2013293</ref> became the first multi-engined monocoque airliner, before being destroyed under orders of the Inter-Allied Commission. At the end of WWI, the Inter-Allied Technical Commission published details of the last [[Zeppelin-Lindau Rs.IV|Zeppelin-Lindau flying boat]] showing its monocoque construction. In the UK, [[Oswald Short]] built a number of experimental aircraft with metal monocoque fuselages starting with the 1920 [[Short Silver Streak]] in an attempt to convince the air ministry of its superiority over wood. Despite advantages, aluminium alloy monocoques would not become common until the mid 1930s as a result of a number of factors, including design conservatism and production setup costs. Short would eventually prove the merits of the construction method with a series of flying boats, whose metal hulls didn't absorb water as the wooden hulls did, greatly improving performance. In the United States, Northrop was a major pioneer, introducing techniques used by his own company and Douglas with the [[Northrop Alpha]]."}},
{"article_title": "Microwave oven", "pageid": "58017", "revid": "1060577656", "timestamp": "2021-12-16T10:56:20Z", "history_paths": [["Microwave oven --- Introduction ---", "History"]], "categories": ["ovens", "microwave technology", "american inventions", "radiation effects", "products introduced in 1945", "20th-century inventions", "home appliances"], "heading_tree": {"Microwave oven --- Introduction ---": {"History": {"Early developments": {}, "Cavity magnetron": {}, "Discovery": {}, "Commercial availability": {}, "Residential use": {}}, "Principles": {"Defrosting": {}, "Fats and sugar": {}, "Thermal runaway": {}, "Penetration": {}, "Energy consumption": {}}, "Components": {"Control panel": {}}, "Variants and accessories": {}, "Heating characteristics": {"Effects on food and nutrients": {}, "Safety benefits and features": {}, "Use in cleaning kitchen sponges": {}}, "Hazards": {"High temperatures": {"Superheating": {}, "Closed containers": {}, "Fires": {}}, "Metal objects": {}, "Direct microwave exposure": {}, "Chemical exposure": {}, "Uneven heating": {}, "Interference": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microwave oven --- Introduction ---|History": "{{multiple image\n| align = right\n| direction = horizontal\n| header   =\n| image1   = Cooking with radio waves - Chicago Worlds Fair 1933.jpg\n| width1   = 200\n| image2   = Cooking with radio waves - Short Wave Craft Nov 1933 cover.jpg\n| width2   = 177\n| footer    = Demonstration by Westinghouse of cooking sandwiches with a 60 MHz shortwave radio transmitter at the [[Century of Progress|1933 Chicago World's Fair]]\n}}\n\nThe exploitation of high-frequency [[radio wave]]s for heating substances was made possible by the development of [[vacuum tube]] [[radio transmitter]]s around 1920. By 1930 the application of [[short wave]]s to heat human tissue had developed into the medical therapy of [[diathermy]].  At the [[Century of Progress|1933 Chicago World's Fair]], [[Westinghouse Electric Corporation|Westinghouse]] demonstrated the cooking of foods between two metal plates attached to a 10 kW, 60 MHz [[shortwave]] [[transmitter]].<ref>{{cite journal | title = Cooking with Short Waves | journal = Short Wave Craft | volume = 4| issue = 7 | page = 394 | date = November 1933 | url = http://www.americanradiohistory.com/Archive-Short-Wave-Television/30s/SW-TV-1933-11.pdf | access-date = 23 March 2015}}</ref>  The Westinghouse team, led by I. F. Mouromtseff, found that foods like steaks and potatoes could be cooked in minutes.\n\nThe 1937 United States patent application by Bell Laboratories states:<ref>{{US patent|2147689}} Chaffee, Joseph G., ''Method and apparatus for heating dielectric materials'', filed 11 August 1937; granted 21 February 1939</ref>\n{{Quotation|This invention relates to heating systems for dielectric materials and the object of the invention is to heat such materials uniformly and substantially simultaneously throughout their mass. ... It has been proposed therefore to heat such materials simultaneously throughout their mass by means of the dielectric loss produced in them when they are subjected to a high voltage, high frequency field.}}\n\nHowever, lower-frequency [[dielectric heating]], as described in the aforementioned patent, is (like [[induction heating]]) an [[Electromagnetism|electromagnetic]] heating effect, the result of the so-called [[near and far field|near-field]] effects that exist in an electromagnetic cavity that is small compared with the [[wavelength]] of the electromagnetic field. This patent proposed radio frequency heating, at 10 to 20 [[megahertz]] (wavelength 30 to 15 meters, respectively).<ref name=  "patent">{{citation | url = http://pdfpiw.uspto.gov/.piw?PageNum=0&docid=02147689&IDKey=49D95666A76C&HomeUrl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO2%2526Sect2%3DHITOFF%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-adv.htm%2526r%3D1%2526p%3D1%2526f%3DG%2526l%3D50%2526d%3DPALL%2526S1%3D2147689.PN.%2526OS%3Dpn%2F2147689%2526RS%3DPN%2F2147689 | publisher = United States Patent and Trademark Office | title = 2,147,689: Method and Apparatus for Heating Dielectric Materials | first = Joseph G. | last = Chaffee | date = 21 February 1939}}</ref> Heating from microwaves that have a wavelength that is small relative to the cavity (as in a modern microwave oven) is due to "far-field" effects that are due to classical [[electromagnetic radiation]] that describes freely propagating light and microwaves suitably far from their source. Nevertheless, the primary heating effect of all types of electromagnetic fields at both radio and microwave frequencies occurs via the dielectric heating effect, as polarized molecules are affected by a rapidly alternating electric field.\n\n [[File:Original cavity magnetron, 1940 (9663811280).jpg|thumb|The [[cavity magnetron]] developed by [[John Randall (physicist)|John Randall]] and [[Harry Boot]] in 1940 at the [[University of Birmingham]], England]]\n\nThe invention of the [[cavity magnetron]] made possible the production of [[electromagnetic wave]]s of a small enough [[wavelength]] ([[microwave]]s). The magnetron was a crucial component in the development of short wavelength [[radar]] during [[World War II]].<ref>{{cite web | url = http://histru.bournemouth.ac.uk/Oral_History/Talking_About_Technology/radar_research/the_magnetron.html | title = The Magnetron | work = Radar Recollections - A Bournemouth University/CHiDE/HLF project | publisher = Defence Electronics History Society (formerly CHiDE)}}</ref> In 1937–1940, a multi-cavity magnetron was built by British physicist [[John Randall (physicist)|Sir John Turton Randall, FRSE]] and coworkers, for the British and American military radar installations in World War II.<ref name="Magnetron"/> A higher-powered microwave generator that worked at shorter [[wavelength]]s was needed, and in 1940, at the [[University of Birmingham]] in England, Randall and [[Harry Boot]] produced a working prototype.<ref>{{cite journal|last=Willshaw|first=W. E.|author2=L. Rushforth|author3=A. G. Stainsby|author4=R. Latham|author5=A. W. Balls|author6=A. H. King|title=The High-power Pulsed Magnetron: Development and Design for Radar Applications|journal=Journal of the Institution of Electrical Engineers - Part IIIA: Radiolocation|year=1946|volume=93|issue=5|doi=10.1049/ji-3a-1.1946.0188|url=https://ieeexplore.ieee.org/document/5299321|access-date=22 June 2012|pages=985\u20131005|archive-url=https://web.archive.org/web/20180505184050/https://ieeexplore.ieee.org/document/5299321/|archive-date=5 May 2018|url-status=dead}}</ref> They invented a [[vacuum tube|valve]] that could produce pulses of microwave radio energy at a wavelength of 10 cm, an unprecedented discovery.<ref name="Magnetron">{{cite news|title=Briefcase 'that changed the world'|url=http://news.bbc.co.uk/1/hi/sci/tech/6331897.stm|publisher=BBC|date=20 October 2017}}</ref>\n\n[[Sir Henry Tizard]] traveled to the U.S. in late September 1940 to offer the magnetron in exchange for their financial and industrial help (see [[Tizard Mission]]).<ref name="Magnetron"/> An early 6 kW version, built in England by the [[General Electric Company plc|General Electric Company]] Research Laboratories, [[Wembley]], London, was given to the [[Federal government of the United States|U.S. government]] in September 1940. The magnetron was later described by American historian James Phinney Baxter III as "[t]he most valuable cargo ever brought to our shores".<ref>{{cite book|first=James Phinney III|last= Baxter|title=Scientists Against Time|location= Boston|publisher=Little, Brown, and Co.|year= 1946|page= 142}}</ref> Contracts were awarded to [[Raytheon]] and other companies for the mass production of the magnetron.\n\n [[File:Wall of microwaves.JPG|thumb|Microwave ovens, several from the 1980s]]\nIn 1945, the heating effect of a high-power microwave beam was accidentally discovered by [[Percy Spencer]], an American self-taught engineer from [[Howland, Maine]]. Employed by [[Raytheon]] at the time, he noticed that microwaves from an active radar set he was working on started to melt a [[Mr. Goodbar|chocolate bar]] he had in his pocket. The first food deliberately cooked with Spencer's microwave oven was popcorn, and the second was an egg, which exploded in the face of one of the experimenters.<ref>{{cite web| url=http://www.gallawa.com/history.html | archive-url=https://web.archive.org/web/20130531120513/http://www.gallawa.com/history.html | url-status=dead | archive-date=2013-05-31 |title=The History of the Microwave Oven |first=John Carlton|last= Gallawa |year=1998}}</ref><ref>{{YouTube|4h1ESUz2H3E|Radar \u2014 Father of the Microwave Oven}}</ref>\n\nTo verify his finding, Spencer created a high density electromagnetic field by feeding microwave power from a magnetron into a metal box from which it had no way to escape. When food was placed in the box with the microwave energy, the temperature of the food rose rapidly. On 8 October 1945, Raytheon filed a United States patent application for Spencer's microwave cooking process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.<ref>{{US patent reference |number=2495429 |y=1950 |m=January |d=24 |inventor=Spencer, Percy L. |title=Method of treating foodstuffs}}</ref>\n\nAnother early discovery of microwave oven technology was by British scientists who in the 1950s used it to reanimate [[Cryogenics|cryogenically]] frozen [[hamsters]].<ref>{{Cite journal|last1=Smith|first1=A. U.|last2=Lovelock|first2=J. E.|last3=Parkes|first3=A. S.|date=June 1954|title=Resuscitation of Hamsters after Supercooling or Partial Crystallization at Body Temperatures Below 0\u00b0 C.|url=https://www.nature.com/articles/1731136a0|journal=Nature|language=en|volume=173|issue=4415|pages=1136\u20131137|doi=10.1038/1731136a0|pmid=13165726|bibcode=1954Natur.173.1136S|s2cid=4242031|issn=1476-4687}}</ref><ref>{{Cite journal|last1=Lovelock|first1=J. E.|last2=Smith|first2=Audrey U.|date=1959|title=Heat Transfer from and to Animals in Experimental Hypothermia and Freezing|url=https://nyaspubs.onlinelibrary.wiley.com/doi/abs/10.1111/j.1749-6632.1959.tb49226.x|journal=Annals of the New York Academy of Sciences|language=en|volume=80|issue=2|pages=487\u2013499|doi=10.1111/j.1749-6632.1959.tb49226.x|pmid=14418500|bibcode=1959NYASA..80..487L|s2cid=38417606|issn=1749-6632}}</ref><ref>{{Cite journal|last1=Andjus|first1=R. K.|last2=Lovelock|first2=J. E.|date=1955|title=Reanimation of rats from body temperatures between 0 and 1\u00b0 C by microwave diathermy|url= |journal=The Journal of Physiology|language=en|volume=128|issue=3|pages=541\u2013546|doi=10.1113/jphysiol.1955.sp005323|issn=1469-7793|pmc=1365902|pmid=13243347}}</ref>\n\n [[File:NS Savannah microwave oven MD8.jpg|thumb|left|upright|Raytheon RadaRange aboard the [[NS Savannah|NS ''Savannah'']] nuclear-powered cargo ship, installed circa 1961]]\n\nIn 1947, Raytheon built the "Radarange", the first commercially available microwave oven.<ref>{{cite web| url=http://www.raytheon.com/ourcompany/history/leadership/ |archive-url=https://web.archive.org/web/20130322044917/http://www.raytheon.com/ourcompany/history/leadership/ |archive-date=2013-03-22 |title=Technology Leadership |publisher=Raytheon}}</ref> It was almost {{convert|1.8|m|ftin}} tall, weighed {{convert|340|kg|lb}} and cost about US$5,000 (${{formatnum:{{Inflation|US|5000|1947|r=-3}}}} in {{Inflation-year|US}} dollars) each. It consumed 3 kilowatts, about three times as much as today's microwave ovens, and was water-cooled. The name was the winning entry in an employee contest.<ref>{{cite book|last= Gallawa|first= J Carlton|chapter= A Brief History of the Microwave Oven|title= The complete microwave oven service handbook : operation, maintenance, troubleshooting, and repair|chapter-url= http://www.smecc.org/microwave_oven.htm|location= Englewood Cliffs, N.J.|publisher= Prentice Hall|date= 1989|access-date= 2017-10-11|isbn= 9780131620179|oclc= 18559256|url-access= registration|url= https://archive.org/details/completemicrowav00gall}} Chapter link is hosted at the Southwest Museum of Engineering, Communication and Computation; [[Glendale, Arizona]].</ref> An early Radarange was installed (and remains) in the galley of the nuclear-powered passenger/cargo ship [[NS Savannah|NS ''Savannah'']]. An early commercial model introduced in 1954 consumed 1.6 kilowatts and sold for US$2,000 to US$3,000 (${{formatnum:{{Inflation|US|2000|1954|r=-3}}}} to ${{formatnum:{{Inflation|US|3000|1954|r=-3}}}} in {{Inflation-year|US}} dollars). Raytheon licensed its technology to the [[Tappan (brand)|Tappan]] Stove company of [[Mansfield, Ohio]] in 1952.<ref>{{cite web|url=https://ohiohistory.wordpress.com/2010/11/02/do-you-remember-your-familys-first-microwave/ |title=Do you remember your family's first microwave? |work=Ohio Historical Society |date=2 November 2010 |url-status=dead |archive-url=https://web.archive.org/web/20160422025448/https://ohiohistory.wordpress.com/2010/11/02/do-you-remember-your-familys-first-microwave/ |archive-date=22 April 2016 }}</ref> Under contract to Whirlpool, Westinghouse, and other major appliance manufacturers looking to add matching microwave ovens to their conventional oven line, Tappan produced several variations of their built-in model from roughly 1955 to 1960. Due to maintenance (some units were water cooled), in-built requirement, and cost (US$1,295 (${{formatnum:{{Inflation|US|1295|1955|r=-3}}}} in {{Inflation-year|US}} dollars)), sales were limited.\n\nJapan's [[Sharp Corporation]] began manufacturing microwave ovens in 1961. Between 1964 and 1966, Sharp introduced the first microwave oven with a turntable, an alternative means to promote more even heating of food.<ref>{{cite web |title=History of Sharp |url=http://www.sharpusa.com/aboutsharp/companyprofile/sharpandtechnologyhistory.aspx |website=[[Sharp Corporation]] |access-date=26 June 2018 |language=en}}</ref> In 1965, Raytheon, looking to expand their Radarange technology into the home market, acquired [[Amana (appliances)|Amana]] to provide more manufacturing capability. In 1967, they introduced the first popular home model, the countertop Radarange, at a price of US$495 (${{formatnum:{{Inflation|US|495|1967|r=-3}}}} in {{Inflation-year|US}} dollars). Unlike the Sharp models, a motor driven [[mode stirrer]] in the top of the oven cavity rotated allowing the food to remain stationary.\n\nIn the 1960s,{{specify|date=November 2013}} [[Litton Industries|Litton]] bought [[Studebaker]]'s Franklin Manufacturing assets, which had been manufacturing magnetrons and building and selling microwave ovens similar to the Radarange. Litton developed a new configuration of the microwave oven: the short, wide shape that is now common. The magnetron feed was also unique. This resulted in an oven that could survive a no-load condition: an empty microwave oven where there is nothing to absorb the microwaves. The new oven was shown at a [[trade show]] in Chicago,{{citation needed|date=October 2013}} and helped begin a rapid growth of the market for home microwave ovens. Sales volume of 40,000 units for the U.S. industry in 1970 grew to one million by 1975. Market penetration was even faster in Japan, due to a less expensive re-engineered magnetron.\nSeveral other companies joined in the market, and for a time most systems were built by defence contractors, who were most familiar with the magnetron. Litton was particularly well known in the restaurant business.\n\n While uncommon today, combination microwave-ranges were offered by major appliance manufacturers through much of the 1970's as a natural progression of the technology. Both Tappan and General Electric offered units that appeared to be conventional stove top/oven ranges, but included microwave capability in the conventional oven cavity. Such ranges were attractive to consumers since both microwave energy and conventional heating elements could be used simultaneously to speed cooking, and there was no loss of countertop space. The proposition was also attractive to manufacturers as the additional component cost could better be absorbed compared with countertop units where pricing was increasingly market-sensitive.\n\nBy 1972, Litton (Litton Atherton Division, Minneapolis) introduced two new microwave ovens, priced at $349 and $399, to tap into the market estimated at $750 million by 1976, according to Robert I Bruder, president of the division.<ref>[https://www.nytimes.com/1972/07/14/archives/litton-introduces-microwave-ovens.html Litton Introduces Microwave Ovens]. [[New York Times]], 14 July 1972, p. 38.</ref> While prices remained high, new features continued to be added to home models. Amana introduced automatic defrost in 1974 on their RR-4D model, and was the first to offer a microprocessor controlled digital control panel in 1975 with their RR-6 model.\n[[File:1971rr4.jpg|thumb|1974 Radarange [[RR-4]].\nBy the late 1970s, technological advances led to rapidly falling prices. Often called "electronic ovens" in the 1960s, the name "microwave oven" later gained currency, and they are now informally called "microwaves".]]\n\nThe late 1970s saw an explosion of low-cost countertop models from many major manufacturers.\n\nFormerly found only in large industrial applications, microwave ovens increasingly became a standard fixture of residential kitchens in [[Developed country|developed countries]]. By 1986, roughly 25% of households in the U.S. owned a microwave oven, up from only about 1% in 1971;<ref name="CPI_US">{{citation | url = http://www.bls.gov/cpi/cpimwo.htm | title = Hedonic Quality Adjustment Methods For Microwave Ovens In the U.S. CPI | first = Paul R. | last = Liegey | date = 16 October 2001 | access-date = 5 October 2013 | publisher = Bureau of Labor Statistics, United States Department of Labor}}</ref> the U.S. Bureau of Labor Statistics reported that over 90% of American households owned a microwave oven in 1997.<ref name="CPI_US"/><ref>{{citation | last1 = Cox | first1 = W. Michael | last2 = Alm | first2 = Richard | year = 1997 | title = Time Well Spent: The Declining Real Cost of Living in America | publisher = Federal Reserve Bank of Dallas | work = 1997 Annual Report | page = 22 (see Exhibit 8) | url = http://www.dallasfed.org/htm/pubs/pdfs/anreport/arpt97.pdf | access-date = 8 May 2016 | archive-date = 19 October 2004 | archive-url = https://web.archive.org/web/20041019184847/http://www.dallasfed.org/htm/pubs/pdfs/anreport/arpt97.pdf | url-status = dead | df = dmy-all }}</ref> In Australia, a 2008 market research study found that 95% of kitchens contained a microwave oven and that 83% of them were used daily.<ref>{{citation | url = http://newsroom.electrolux.com/au/files/2010/01/Westinghouse-How-Australia-Cooks-Report1.pdf | title = The Westinghouse How Australia Cooks Report | date = October 2008 | publisher = Westinghouse | access-date = 5 February 2015}}</ref> In Canada, fewer than 5% of households had a microwave oven in 1979, but more than 88% of households owned one by 1998.<ref>{{cite journal | url = http://www.statcan.gc.ca/pub/11-008-x/11-008-x2000003-eng.pdf | title = Income and expenditures | first = Cara | last = Williams | date = Winter 2000 | number = 59 | journal = Canadian Social Trends \u2014 Catalogue No. 11-008 | pages = 7\u201312 | quote = Microwaves have been adopted even more avidly: in 1979, less than 5% of households had one, but by 1998 over 88% did.}}</ref> In France, 40% of households owned a microwave oven in 1994, but that number had increased to 65% by 2004.<ref>{{citation | url = http://www.freedoniagroup.com/brochure/20xx/2015smwe.pdf | title = World Major Household Appliances: World Industry Study with Forecasts to 2009 & 2014 (Study #2015) | date = January 2006 | at = TABLE VI-5: FRANCE COOKING APPLIANCES SUPPLY & DEMAND (million dollars) | publisher = The Freedonia Group | location = Cleveland, Ohio}}</ref>\n\nAdoption has been slower in [[Developing country|less-developed countries]], as households with disposable income concentrate on more important household appliances like [[refrigerators]] and ovens. In [[India]], for example, only about 5% of households owned a microwave oven in 2013, well behind refrigerators at 31% ownership.<ref>{{cite web | title = Household penetration rate of home appliances in India in 2013 | url = http://www.statista.com/statistics/370635/household-penetration-home-appliances-india/ | access-date = 5 February 2015 | publisher = Statistica}}</ref> However, microwave ovens are gaining popularity. In Russia, for example, the number of households with a microwave oven grew from almost 24% in 2002 to almost 40% in 2008.<ref name=USDA-microwave/> Almost twice as many households in South Africa owned microwave ovens in 2008 (38.7%) as in 2002 (19.8%).<ref name=USDA-microwave/> Microwave oven ownership in Vietnam was at 16% of households in 2008\u2014versus 30% ownership of refrigerators; this rate was up significantly from 6.7% microwave oven ownership in 2002, with 14% ownership for refrigerators that year.<ref name=USDA-microwave>{{citation | url = http://www.ers.usda.gov/media/612721/householdamenities.xls | archive-url = https://web.archive.org/web/20130626225554/http://www.ers.usda.gov/media/612721/householdamenities.xls | url-status = dead | archive-date = 26 June 2013 | format = XLS | title = Ownership of household amenities among selected countries | publisher = Economic Research Service, United States Department of Agriculture | year = 2009 | access-date = 5 February 2015 }}</ref>\n\nConsumer household microwave ovens usually come with a cooking power of 600 watts and up (with 1000 or 1200 watts on some models). The size of household microwave ovens can vary, but usually have an internal volume of around {{convert|20|l|cuin cuft|sp=us|}}, and external dimensions of approximately {{convert|45|-|60|cm|ftin|abbr=on|}} wide, {{convert|35|-|40|cm|ftin|abbr=on|}} deep and {{convert|25|-|35|cm|ftin|abbr=on|}} tall.\n\nMicrowaves can be turntable or flatbed. Turntable ovens include a glass plate or tray. Flatbed ones do not include a plate, so they have a flat and wider cavity .<ref name=":1">{{Cite book|last=Williams|first=Alison|url=https://escholarship.org/content/qt3s29h7wd/qt3s29h7wd.pdf|title=Surveys of Microwave Ovens in U.S. Homes|publisher=Lawrence Berkeley National Laboratory|date=2012-12-05|pages=6, 18 and so on}}</ref><ref>{{Cite journal|last=ANNIS|first=PATTY J.|date=1980-08-01|title=Design and Use of Domestic Microwave Ovens|url=https://doi.org/10.4315/0362-028X-43.8.629|journal=Journal of Food Protection|volume=43|issue=8|pages=629\u2013632|doi=10.4315/0362-028X-43.8.629|pmid=30822984|issn=0362-028X}}</ref><ref name=":2">{{Cite journal|date=2016-07-01|title=Thawing in a microwave cavity: Comprehensive understanding of inverter and cycled heating|url=https://www.sciencedirect.com/science/article/abs/pii/S0260877416300395|journal=Journal of Food Engineering|language=en|volume=180|pages=87\u2013100|doi=10.1016/j.jfoodeng.2016.02.007|issn=0260-8774|last1=Chen|first1=Fangyuan|last2=Warning|first2=Alexander D.|last3=Datta|first3=Ashim K.|last4=Chen|first4=Xing}}</ref>\n\nBy position and type, [[United States Department of Energy|US DOE]] classifies them in (1) [[countertop]] or (2) [[Kitchen stove|over the range]] and built-in (wall oven for a [[Cabinetry|cabinet]] or a [[drawer]] model).<ref name=":1" />\n\nTraditional microwaves rely on internal high voltage power from a line/mains transformer, but many newer models are powered by an inverter. Inverter microwaves can be useful for achieving more even cooking results, as they offer a seamless stream of cooking power.\n\nA traditional microwave only has two heat settings, ON and OFF. Intermediate heat settings switch between full power and off every few seconds, with more time ON for higher settings. \n\nAn inverter type, however, can sustain lower temperatures for a lengthy duration without having to switch itself off and on repeatedly. Apart from offering superior cooking ability, these microwaves are generally more energy-efficient.<ref name=":3">{{Cite journal|last1=Kako|first1=H.|last2=Nakagawa|first2=T.|last3=Narita|first3=R.|date=August 1991|title=Development of compact inverter power supply for microwave oven|url=https://ieeexplore.ieee.org/document/85575|journal=IEEE Transactions on Consumer Electronics|volume=37|issue=3|pages=611\u2013616|doi=10.1109/30.85575|issn=1558-4127}}</ref><ref name=":2" /><ref name=":4">{{Cite journal|last1=Lee|first1=Min-Ki|last2=Koh|first2=Kang-Hoon|last3=Lee|first3=Hyun--Woo|date=2004|title=A Study on Constant Power Control of Half Bridge Inverter for Microwave Oven|url=https://www.koreascience.or.kr/article/JAKO200411922336424.page|journal=KIEE International Transaction on Electrical Machinery and Energy Conversion Systems|volume=4B|issue=2|pages=73\u201379|issn=1598-2602}}</ref>\n\n{{As of|2020}}, the majority of countertop microwave ovens (regardless of brand) sold in the United States were manufactured by the [[Midea Group]].<ref>{{cite news |last1=McCabe |first1=Liam |last2=Sullivan |first2=Michael |title=The Best Microwave |url=https://thewirecutter.com/reviews/best-microwave/ |access-date=21 May 2020 |work=Wirecutter |publisher=The New York Times |date=20 May 2020}}</ref>"}},
{"article_title": "Liquid hydrogen", "pageid": "58673", "revid": "1059940010", "timestamp": "2021-12-12T15:31:54Z", "history_paths": [["Liquid hydrogen --- Introduction ---", "History"]], "categories": ["hydrogen physics", "hydrogen technologies", "hydrogen storage", "liquid fuels", "rocket fuels", "coolants", "cryogenics", "hydrogen", "industrial gases", "1898 in science"], "heading_tree": {"Liquid hydrogen --- Introduction ---": {"History": {}, "Spin isomers of hydrogen": {}, "Uses": {}, "Properties": {}, "Safety": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Liquid hydrogen --- Introduction ---|History": "{{further|Timeline of low-temperature technology}}\nIn 1885, [[Zygmunt Florenty Wr\u00f3blewski]] published hydrogen's critical temperature as 33{{nbsp}}K; critical pressure, 13.3 atmospheres; and boiling point, 23{{nbsp}}K.\n\n[[Hydrogen]] was liquefied by [[James Dewar]] in 1898 by using [[regenerative cooling]] and his invention, the [[vacuum flask]]. The first synthesis of the stable isomer form of liquid hydrogen, parahydrogen, was achieved by [[Paul Harteck]] and [[Karl Friedrich Bonhoeffer]] in 1929."}},
{"article_title": "Timeline of low-temperature technology", "pageid": "58740", "revid": "1056965977", "timestamp": "2021-11-24T16:25:06Z", "history_paths": [["Timeline of low-temperature technology --- Introduction ---", "Prior to the 19th century"], ["Timeline of low-temperature technology --- Introduction ---", "Prior to the 19th century"], ["Timeline of low-temperature technology --- Introduction ---", "19th century"], ["Timeline of low-temperature technology --- Introduction ---", "20th century"], ["Timeline of low-temperature technology --- Introduction ---", "21st century"]], "categories": ["technology timelines", "cryogenics", "cooling technology", "industrial gases", "refrigerants"], "heading_tree": {"Timeline of low-temperature technology --- Introduction ---": {"Prior to the 19th century": {}, "19th century": {}, "20th century": {}, "21st century": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Timeline of low-temperature technology --- Introduction ---|Prior to the 19th century": "* {{ca.|1700 BC}} \u2013 [[Zimri-Lim]], ruler of Mari in Syria commanded the construction of one of the first [[Ice house (building)|ice house]]s near the [[Euphrates]].<ref name="Dalley2002">{{cite book|author=Stephanie Dalley|author-link=Stephanie Dalley|title=Mari and Karana: Two Old Babylonian Cities|url=https://books.google.com/books?id=_oTh51M5XF4C&pg=PA91|date=1 January 2002|publisher=Gorgias Press LLC|isbn=978-1-931956-02-4|page=91}}</ref>\n* {{ca.|500 BC}} \u2013 The [[yakhchal]] (meaning "ice pit" in Persian) is an ancient Persian type of refrigerator. The structure was formed from a mortar resistant to heat transmission, in the shape of a dome. Snow and ice was stored beneath the ground, effectively allowing access to ice even in hot months and allowing for prolonged [[food preservation]]. Often a [[badgir]] was coupled with the [[yakhchal]] in order to slow the heat loss. Modern refrigerators are still called yakhchal in Persian.\n* {{ca.|60 AD}} - [[Hero of Alexandria]] knew of the principle that certain substances, notably air, expand and contract and described a demonstration in which a closed tube partially filled with air had its end in a container of water.<ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'' {{ISBN|0-471-62767-4}}</ref> The expansion and contraction of the air caused the position of the water/air interface to move along the tube. This was the first established principle of gas behaviour vs temperature, and principle of first thermometers later on. The idea could predate him even more ([[Empedocles]] of Agrigentum in his 460 B.C. book On Nature).\n* 1396 AD - Ice storage warehouses called "Dong-bing-go-tango" (meaning "east ice storage warehouse" in Korean) and Seo-bing-go ("west ice storage warehouse") were built in Han-Yang (currently Seoul, Korea). The buildings housed ice that was collected from the frozen Han River in January (by lunar calendar). The warehouse was well-insulated, providing the royal families with ice into the summer months.{{citation needed|date=October 2012}} These warehouses were closed in 1898 AD but the buildings are still intact in Seoul.\n* 1593 \u2013 [[Galileo Galilei]] builds a first modern [[thermoscope]]. But it is possible the invention was by [[Santorio Santorio]] or independently around same time by [[Cornelis Drebbel]]. The principle of operation was known in [[Ancient Greece]].\n* {{ca.|1611}}-1613 \u2013 Francesco Sagredo or [[Santorio Santorio]], put a numerical scale on a thermoscope.\n* 1617 \u2013 [[Giuseppe Biancani]] publishes first clear diagram of thermoscope\n* 1638 \u2013 [[Robert Fludd]] describes thermometer with a scale, using air thermometer principle with column of air and liquid water.\n* 1650 \u2013 [[Otto von Guericke]] designed and built the world's first [[vacuum pump]] and created the world's first ever [[vacuum]] known as the [[Magdeburg hemispheres]]  to disprove [[Aristotle]]'s long-held supposition that '[[Nature abhors a vacuum]]'.\n* 1656 \u2013 [[Robert Boyle]] and [[Robert Hooke]] built an [[air pump]] on this design.\n* 1662 \u2013 [[Boyle's law]] (gas law relating pressure and volume) is demonstrated using a [[vacuum pump]]\n* 1665 \u2013 Boyle theorizes a minimum temperature in ''New Experiments and Observations touching Cold''.\n* 1679 \u2013 [[Denis Papin]] \u2013 [[safety valve]]\n* 1702 \u2013 [[Guillaume Amontons]] first calculates [[absolute zero]] to be \u2212240 \u00b0C using an air thermometer of his own invention (1702), theorizing at this point the gas would reach zero volume and zero pressure.\n* 1714 \u2013 [[Daniel Gabriel Fahrenheit]] invented the first reliable thermometer, using mercury instead of alcohol and water mixtures\n* 1724 \u2013 [[Daniel Gabriel Fahrenheit]] proposes a Fahrenheit scale, which had finer scale and greater reproducibility than competitors.\n* 1730 \u2013 [[Ren\u00e9 Antoine Ferchault de R\u00e9aumur]] invented an alcohol thermometer and temperature scale ultimately proved to be less reliable than Fahrenheit's mercury thermometer.\n* 1742 \u2013 [[Anders Celsius]] proposed a scale with zero at the boiling point and 100 degrees at the freezing point of water. It was later changed to be the other way around, on the input from Swedish academy of science.\n* 1755 - [[William Cullen]] used a pump to create a partial [[vacuum]] over a container of [[diethyl ether]], which then [[boiling point|boiled]], absorbing [[heat of vaporization|heat]] from the surrounding air.<ref>{{cite book|last=Arora|first=Ramesh Chandra|title=Refrigeration and Air Conditioning|publisher=PHI Learning|location=New Delhi, India|isbn=978-81-203-3915-6|page=3|chapter=Mechanical vapour compression refrigeration|date=30 March 2012}}</ref>\n* 1756 \u2013 The first documented public demonstration of artificial [[refrigeration]] by [[William Cullen]]<ref>William Cullen, ''Of the Cold Produced by Evaporating Fluids and of Some Other Means of Producing Cold,'' '''in''' Essays and Observations Physical and Literary Read Before a Society in Edinburgh and Published by Them, II, (Edinburgh 1756)</ref>\n* 1782 \u2013 [[Antoine Lavoisier]] and [[Pierre-Simon Laplace]] invent the [[Calorimetry|ice-calorimeter]]\n* 1784 \u2013 [[Gaspard Monge]] liquefied the first gas producing liquid [[sulfur dioxide]].\n* 1787 \u2013 [[Charles's law]] (Gas law, relating volume and temperature)", "Timeline of low-temperature technology --- Introduction ---|19th century": "* 1802 \u2013 [[John Dalton]] wrote "the reducibility of all elastic fluids of whatever kind, into liquids"\n* 1802 \u2013 [[Gay-Lussac's law]] (Gas law, relating temperature and pressure).\n* 1803 \u2013 Domestic [[ice box]]\n* 1803 \u2013 Thomas Moore of Baltimore, Md. received a patent on refrigeration.<ref>[http://www.waterfordhistory.org/history/waterford-thomas-moore.htm 1803 \u2013 Thomas Moore]</ref>\n* 1805 \u2013 [[Oliver Evans]] designed the first closed circuit refrigeration machine based on the [[vapor-compression refrigeration]] cycle.\n* 1809 \u2013 [[Jacob Perkins]] patented the first refrigerating machine\n* 1810 \u2013 [[John Leslie (physicist)|John Leslie]] [[freezing|freeze]]s [[water]] to ice by using an [[airpump]].\n* 1811 \u2013 [[Avogadro's law]] a gas law\n* 1823 \u2013 [[Michael Faraday]] liquified ammonia to cause cooling\n* 1824 \u2013 [[Nicolas L\u00e9onard Sadi Carnot|Sadi Carnot]] \u2013 the [[Carnot Cycle]]\n* 1834 \u2013 [[Ideal gas law]] by [[Beno\u00eet Paul \u00c9mile Clapeyron|\u00c9mile Clapeyron]]\n* 1834 \u2013 [[\u00c9mile Clapeyron]] characterizes phase transitions between two phases in form of [[Clausius\u2013Clapeyron relation]].\n* 1834 \u2013 [[Jacob Perkins]] obtained the first patent for a [[vapor-compression refrigeration]] system.\n* 1834 \u2013 [[Jean-Charles Peltier]] discovers the [[Peltier effect]]\n* 1844 \u2013 [[Charles Piazzi Smyth]] proposes comfort cooling<ref>[http://infomotions.com/etexts/gutenberg/dirs/1/8/3/3/18337/18337.htm 1844 \u2013 Charles Piazzi Smyth] {{webarchive|url=https://web.archive.org/web/20120210085439/http://infomotions.com/etexts/gutenberg/dirs/1/8/3/3/18337/18337.htm |date=2012-02-10 }}</ref>\n* c.1850 \u2013 [[Michael Faraday]] makes a hypothesis that freezing substances increases their dielectric constant.\n* 1851 \u2013 [[John Gorrie]] patented his mechanical refrigeration machine in the US to make ice to cool the air<ref>[http://www.myoutbox.net/popch20.htm 1851 John Gorrie]</ref><ref>{{cite web|url=http://patimg2.uspto.gov/.piw?Docid=00008080&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%2526Sect2%3DHITOFF%2526d%3DPALL%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r%3D1%2526f%3DG%2526l%3D50%2526s1%3D0008,080.PN.%2526OS%3DPN%2F0008,080%2526RS%3DPN%2F0008,080&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|title=Patent Images|access-date=15 March 2015}}</ref>\n* 1852 \u2013 [[James Prescott Joule]] and [[William Thomson, 1st Baron Kelvin]] discover [[Joule\u2013Thomson effect]]\n* 1856 \u2013 [[James Harrison (engineer)|James Harrison]] patented an ether liquid-vapour compression refrigeration system and developed the first practical ice-making and refrigeration room for use in the brewing and meat-packing industries of [[Geelong]], Victoria, Australia.\n* 1856 \u2013 [[August Kr\u00f6nig]] simplistic foundation of [[kinetic theory of gases]].\n* 1857 \u2013 [[Rudolf Clausius]] creates a sophisticated theory of gases based including all [[degrees of freedom]], as well derives [[Clausius\u2013Clapeyron relation]] from basic principles.\n* 1857 \u2013 [[Carl Wilhelm Siemens]], the [[Siemens cycle]]\n* 1858 \u2013 [[Julius Pl\u00fccker]] observed for the first time some pumping effect due to electrical discharge.\n* 1859 \u2013 [[James Clerk Maxwell]] determines distribution of velocities and kinetic energies in a gas, and explains emergent property of temperature and heat, and creates a first law of statistical mechanics.\n* 1859 \u2013 [[Ferdinand Carr\u00e9]] \u2013 The first [[Absorption refrigeration|gas absorption]] refrigeration system using gaseous ammonia dissolved in water (referred to as "aqua ammonia")\n* 1862 \u2013 [[Alexander Carnegie Kirk]] invents the [[Air cycle machine]]\n* 1864 \u2013 [[Charles Tellier]] patented a refrigeration system using [[dimethyl ether]]\n* 1867 - [[Thaddeus S. C. Lowe]] patented a refrigeration system using [[carbon dioxide]], and in 1869 made ice making machine using dry carbon dioxide. The same year Lowe bought a steamship and put a compressor based refrigeration device on it for transport of frozen meat.\n* 1869 \u2013 [[Charles Tellier]] installed a cold storage plant in France.\n* 1869 \u2013 [[Thomas Andrews (scientist)|Thomas Andrews]] discovers existence of a [[critical point (thermodynamics)|critical point]] in fluids.\n* 1871 \u2013 [[Carl von Linde]] built his first [[ammonia]] compression machine.\n* c.a. 1873 \u2013 [[Johannes Diderik van der Waals|Van der Waals]] publishes and proposes a [[real gas]] model named later a [[Van der Waals equation]].\n* 1875 - [[Raoul Pictet]] develops a refrigeration machine using [[sulphur dioxide]] to combat high-pressure problems of ammonia in when used in tropical climates (mainly for the purpose of shipping meat).\n* 1876 \u2013 [[Carl von Linde]] patented equipment to liquefy air using the [[Joule\u2013Thomson effect|Joule Thomson expansion process]] and [[regenerative cooling]]<ref>{{cite web|url=https://history.nasa.gov/SP-4404/app-a1.htm|title=app-a1|access-date=15 March 2015}}</ref>\n* 1877 \u2013 [[Raoul Pictet]] and [[Louis Paul Cailletet]], working separately, develop two methods to liquefy [[oxygen]].\n* 1879 \u2013 [[Brayton cycle#Reverse Brayton cycle|Bell-Coleman machine]]\n* 1882 \u2013 [[William Soltau Davidson]] fitted a compression refrigeration unit to the New Zealand vessel [[Dunedin (ship)|''Dunedin'']]\n* 1883 \u2013 [[Zygmunt Wr\u00f3blewski]] condenses experimentally useful quantities of [[liquid oxygen]]\n* 1885 \u2013 [[Zygmunt Wr\u00f3blewski]] published hydrogen's critical temperature as 33 K; critical pressure, 13.3 atmospheres; and boiling point, 23 K.\n* 1888 \u2013 [[Loftus Perkins]] develops the "[[Arktos]]" cold chamber for preserving food, using an early ammonia absorption system.\n* 1892 \u2013 [[James Dewar]] invents the vacuum-insulated, silver-plated glass [[Dewar flask]]\n* 1895 \u2013 [[Carl von Linde]] files for [[patent]] protection of the [[Hampson\u2013Linde cycle]] for liquefaction of atmospheric air or other gases (approved in 1903).\n* 1898 \u2013 James Dewar condenses [[liquid hydrogen]] by using [[regenerative cooling]] and his invention, the [[vacuum flask]].", "Timeline of low-temperature technology --- Introduction ---|20th century": "* 1905 \u2013 [[Carl von Linde]] obtains pure liquid [[oxygen]] and [[nitrogen]].\n* 1906 \u2013 [[Willis Carrier]] patents the basis for modern [[air conditioning]].\n* 1908 \u2013 [[Heike Kamerlingh Onnes]] liquifies [[helium]].\n* 1911 \u2013 Heike Kamerlingh Onnes discloses his research on metallic low-temperature phenomenon characterised by no electrical resistance, calling it [[superconductivity]].\n* 1915 \u2013 [[Wolfgang Gaede]] \u2013 the [[Diffusion pump]]\n* 1920 \u2013 Edmund Copeland and Harry Edwards use [[iso-butane]] in small refrigerators.\n* 1922 \u2013 [[Baltzar von Platen (inventor)|Baltzar von Platen]] and [[Carl Munters]] invent the 3 fluids absorption chiller, exclusively driven by heat.\n* 1924 \u2013 [[Fernand Holweck]] \u2013 the [[Holweck pump]]\n* 1926 \u2013 [[Albert Einstein]] and [[Le\u00f3 Szil\u00e1rd]] invent the [[Einstein refrigerator]].\n* 1926 \u2013 [[Willem Hendrik Keesom]] solidifies helium.\n* 1926 \u2013 [[General Electric Company]] introduced the first hermetic compressor refrigerator\n* 1929 - David Forbes Keith of Toronto, Ontario, Canada received a patent for the [[Icy Ball]] which helped hundreds of thousands of families through the [[Dirty Thirties]].\n* 1933 \u2013 [[William Giauque]] and others \u2013 Adiabatic demagnetization refrigeration\n* 1937 \u2013 [[Pyotr Leonidovich Kapitsa]], [[John F. Allen]], and [[Don Misener]] discover [[superfluidity]] using helium-4 at 2.2 [[Kelvin|K]]\n* 1937 \u2013 [[Frans Michel Penning]] invents a type of [[cold cathode]] vacuum gauge known as [[Penning gauge]]\n* 1944 \u2013 [[Manne Siegbahn]], the [[Turbomolecular pump|Siegbahn pump]]\n* 1949 \u2013 S.G. Sydoriak, E.R. Grilly, E.F. Hammel, first measurements on pure 3He in the 1 K range\n* 1950 -  Invention of the so-called Gifford-McMahon cooler by K.W. Taconis (patent US2,567,454)\n* 1951 \u2013 [[Heinz London]] invents the principle of the [[dilution refrigerator]]\n* 1955 \u2013 Willi Becker <!-- April 28, 2011 \u2013 Removed link to politician; no article yet for this pump engineer. --> [[turbomolecular pump]] concept<ref>[http://www.avs.org/pdf/timelineD.pdf Vacuum Science & Technology Timeline]</ref>\n* 1956 \u2013 G.K. Walters, W.M. Fairbank, discovery of phase separation in 3He-4He mixtures\n* 1957 \u2013 Lewis D. Hall, Robert L. Jepsen and John C. Helmer [[Ion pump (physics)|ion pump]] based on Penning discharge\n* 1959 \u2013 [[Kleemenko cycle]]\n* 1960 - Reinvention of the Gifford-McMahon cooler by H.O. McMahon and W.E. Gifford\n* 1965 \u2013 D.O. Edwards, and others, discovery of finite solubility of 3He in 4He at 0K\n* 1965 \u2013 P. Das, R. de Bruyn Ouboter, K.W. Taconis, one-shot dilution refrigerator<ref>{{Cite journal | doi = 10.1016/j.cryogenics.2021.103390| title = Development of Dilution refrigerators \u2013 A review | journal = Cryogenics| volume = 121| year = 2022| last1 = Zu | first1 = H.| last2 = Dai | first2 = W.| last3 = de Waele | first3 = A.T.A.M.| bibcode = 2022Cryo..121....1Z}}</ref>\n* 1966 \u2013 H.E. Hall, P.J. Ford, K. Thomson, continuous dilution refrigerator\n* 1972 \u2013 [[David Lee (physicist)|David Lee]], [[Robert Coleman Richardson]] and [[Douglas Osheroff]] discover superfluidity in helium-3 at 0.002 K.\n* 1973 \u2013 [[Linear compressor]]\n* 1978 \u2013 [[Laser cooling]] demonstrated in the groups of Wineland and Dehmelt.\n* 1983 - Orifice-type [[pulse tube refrigerator]] invented by Mikulin, Tarasov, and Shkrebyonock\n* 1986 \u2013 [[Karl Alexander M\u00fcller]] and [[J. Georg Bednorz]] discover [[high-temperature superconductivity]]\n* 1995 \u2013 [[Eric Cornell]] and [[Carl Wieman]] create the first<ref>{{cite web|title=New State of Matter Seen Near Absolute Zero|url=http://physics.nist.gov/News/Update/950724.html|publisher=NIST|url-status=dead|archive-url=https://web.archive.org/web/20100601175245/http://physics.nist.gov/News/Update/950724.html|archive-date=2010-06-01}}</ref> [[Bose\u2013Einstein condensate]], using a dilute gas of [[Rubidium-87]] cooled to 170 nK. They won the Nobel Prize for Physics in 2001 for BEC.\n* 1999 \u2013 D.J. Cousins and others, dilution refrigerator reaching 1.75 mK\n* 1999 - The current world record lowest temperature was set at 100 picokelvins (pK), or 0.000 000 000 1 of a kelvin, by cooling the nuclear spins in a piece of [[rhodium]] metal.<ref>{{cite web|url = http://ltl.tkk.fi/wiki/LTL/World_record_in_low_temperatures|title = World record in low temperatures|access-date =2009-05-05| archive-url= https://web.archive.org/web/20090618075820/http://ltl.tkk.fi/wiki/LTL/World_record_in_low_temperatures| archive-date=2009-06-18| url-status= live}}</ref>", "Timeline of low-temperature technology --- Introduction ---|21st century": "* 2000 - [[Nuclear spin]] temperatures below 100 pK were reported for an experiment at the [[Helsinki University of Technology]]'s Low Temperature Lab in [[Espoo]], [[Finland]]. However, this was the temperature of one particular [[Degrees of freedom (physics and chemistry)|degree of freedom]] \u2013 a [[quantum]] property called nuclear spin \u2013 not the overall average [[thermodynamic temperature]] for all possible degrees in freedom.<ref>{{cite book|last=Knuuttila|first=Tauno|url=http://www.hut.fi/Yksikot/Kirjasto/Diss/2000/isbn9512252147|title=Nuclear Magnetism and Superconductivity in Rhodium|location=Espoo, Finland|publisher=Helsinki University of Technology|year=2000|isbn=978-951-22-5208-4|access-date=2008-02-11|url-status=dead|archive-url=https://web.archive.org/web/20010428173229/http://www.hut.fi/Yksikot/Kirjasto/Diss/2000/isbn9512252147/|archive-date=2001-04-28}}</ref><ref>{{cite press release|title=Low Temperature World Record|url=http://ltl.hut.fi/Low-Temp-Record.html|publisher=Low Temperature Laboratory, Teknillinen Korkeakoulu|date=8 December 2000|access-date=2008-02-11| archive-url= https://web.archive.org/web/20080218053521/http://ltl.hut.fi/Low-Temp-Record.html| archive-date=2008-02-18| url-status= live}}</ref>\n* 2014 - Scientists in the [[CUORE]] collaboration at the [[Laboratori Nazionali del Gran Sasso]] in Italy cooled a copper vessel with a volume of one cubic meter to {{convert|0.006|K|C F|sigfig=6|abbr=out}} for 15 days, setting a record for the lowest temperature in the known universe over such a large contiguous volume<ref>{{cite news|title=CUORE: The Coldest Heart in the Known Universe.|url=http://www.interactions.org/cms/?pid=1034217|access-date=21 October 2014|publisher=INFN Press Release}}</ref>\n* 2015 - Experimental physicists at [[Massachusetts Institute of Technology]] (MIT) successfully cooled molecules in a gas of sodium potassium to a temperature of 500 nanokelvins, and it is expected to exhibit an exotic [[state of matter]] by cooling these molecules a bit further.<ref>{{cite web|title=MIT team creates ultracold molecules|url=https://newsoffice.mit.edu/2015/ultracold-molecules-0610|work=Massachusetts Institute of Technology, Massachusetts, Cambridge}}</ref>\n* 2015 - A team of atomic physicists from [[Stanford University]] used a matter-wave lensing technique to cool a sample of rubidium atoms to an effective temperature of 50 pK along two spatial dimensions.<ref>{{cite journal |last1=Kovachy |first1=Tim |last2=Hogan |first2=Jason M. |last3=Sugarbaker |first3=Alex |last4=Dickerson |first4=Susannah M. |last5=Donnelly |first5=Christine A. |last6=Overstreet |first6=Chris |last7=Kasevich |first7=Mark A. |date=2015 |title=Matter Wave Lensing to Picokelvin Temperatures |url=https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.114.143004 |journal=Physical Review Letters |volume=114 |issue=14 |pages=143004 |doi=10.1103/PhysRevLett.114.143004|doi-access=free }}</ref>\n* 2017 - [[Cold Atom Laboratory]] (CAL), an experimental instrument launched to the [[International Space Station]] (ISS) in 2018.<ref>{{Cite news|url=https://www.sciencemag.org/news/2017/09/coolest-science-ever-headed-space-station|title=Coolest science ever headed to the space station|date=2017-09-05|work=Science {{!}} AAAS|access-date=2017-09-24|language=en}}</ref> The instrument creates extremely cold conditions in the [[microgravity]] environment of the ISS leading to the formation of [[Bose Einstein Condensate]]s that are a magnitude colder than those that are created in laboratories on Earth. In this space-based laboratory, up to 20 seconds interaction times and as low as 1 picokelvin (<math>10^{-12}</math> K) temperatures are projected to be achievable, and it could lead to exploration of unknown [[Quantum mechanics|quantum mechanical]] phenomena and test some of the most fundamental laws of physics.<ref name="NASA Cold Atom Laboratory Mission">{{cite web |url=http://coldatomlab.jpl.nasa.gov/mission/ |archive-url=https://web.archive.org/web/20130329092843/http://coldatomlab.jpl.nasa.gov/mission/ |url-status=dead |archive-date=2013-03-29 |title=Cold Atom Laboratory Mission |work=Jet Propulsion Laboratory |publisher=NASA |date=2017 |access-date=2016-12-22 }}</ref><ref name="CALnasa">{{cite web |url=http://www.nasa.gov/mission_pages/station/research/news/cold_atom_lab/ |title=Cold Atom Laboratory Creates Atomic Dance |work=NASA News |date=26 September 2014 |access-date=2015-05-21 }}</ref>"}},
{"article_title": "Timeline of rocket and missile technology", "pageid": "58741", "revid": "1062256166", "timestamp": "2021-12-27T09:22:07Z", "history_paths": [["Timeline of rocket and missile technology --- Introduction ---"], ["Timeline of rocket and missile technology --- Introduction ---", "11th century"], ["Timeline of rocket and missile technology --- Introduction ---", "17th century-19th century"], ["Timeline of rocket and missile technology --- Introduction ---", "20th century"], ["Timeline of rocket and missile technology --- Introduction ---", "21st century"]], "categories": ["aviation timelines", "spaceflight timelines", "military timelines", "science timelines", "technology timelines"], "heading_tree": {"Timeline of rocket and missile technology --- Introduction ---": {"11th century": {}, "17th century-19th century": {}, "20th century": {}, "21st century": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Timeline of rocket and missile technology --- Introduction ---": "{{Refimprove|date=December 2009}}\n{{see also|Timeline of the gunpowder age}}\n[[File:11th century long serpent fire arrow rocket launcher.jpg|thumb|right|180px|A depiction of the "long serpent" rocket launcher from the 11th century book ''[[Wujing Zongyao]]''. The holes in the frame are designed to keep the fire arrows separate.]]\nThis article gives a concise '''[[timeline]] of [[rocket]] and [[missile]] [[technology]]'''.\n\n * 11th century AD - The first documented record of [[gunpowder]] and the [[fire arrow]], an early form of rocketry, appears in the Chinese text ''[[Wujing Zongyao]]''.\n\n * 1633 - [[Lag\u00e2ri Hasan \u00c7elebi]] launched a 7-winged rocket using 50 okka (140 lbs) of gunpowder from Sarayburnu, the point below [[Topkap\u0131 Palace]] in [[Istanbul]].<ref name="refLAGARI">Winter, Frank H. (1992). "Who First Flew in a Rocket?", Journal of the British Interplanetary Society 45 (July 1992), p. 275-80</ref>\n* 1650 - ''Artis Magnae Artilleriae pars prima'' ("Great Art of Artillery, the First Part") is printed in Amsterdam, about a year before the death of its author, [[Kazimierz Siemienowicz]].\n* 1664 - A "space rocket" is imagined as a future technology to be studied in France and its drawing is ordered by [[France|French]] finance minister [[Jean-Baptiste Colbert|Colbert]]; designed by [[Charles Le Brun|Le Brun]] on a [[Gobelins manufactory|Gobelins]] tapestry<ref>{{cite web|url=https://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1972x006x004/HSMx1972x006x004x0250.pdf|archive-url=https://web.archive.org/web/20190426061726/https://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1972x006x004/HSMx1972x006x004x0250.pdf|url-status=dead|archive-date=2019-04-26|title=Astronautique|author=Jean Cheymol|website=Biusante.parisdescartes.fr|access-date=2017-08-11}}</ref> (see: [[French space program]])\n* 1798 - [[Tipu Sultan]], the King of the state of [[Mysore]] in India, develops and uses iron rockets against the British Army (see [[Mysorean rockets]]).\n* 1801 - The British Army develops the [[Congreve rocket]] based on weapons used against them by [[Tipu Sultan]].\n* 1806 - [[Claude Ruggieri]], an Italian living in France, launched animals on rockets and recovered them using parachutes. He was prevented from launching a child by police.<ref>{{cite web|url=http://history.msfc.nasa.gov/rocketry/14.html|archive-url=https://web.archive.org/web/20010215015030/http://history.msfc.nasa.gov/rocketry/14.html|url-status=dead|archive-date=15 February 2001|title=MSFC History OFFICE: CLAUDE RUGGIERI|publisher=History.msfc.nasa.gov|access-date=30 November 2014}}</ref>\n* 1813 - "A Treatise on the Motion of Rockets" by [[William Moore (British mathematician)|William Moore]] \u2013 first appearance of the [[rocket equation]]\n* 1818 - [[Henry Trengrouse]] demonstrates his rocket apparatus for projecting a lifeline from a wrecked ship to the shore, later widely adopted\n* 1844 - [[William Hale (British inventor)|William Hale]] invents the [[Spin-stabilisation|spin-stabilized]] rocket\n* 1861 - [[William Leitch (scientist)|William Leitch]] publishes an essay "A Journey Through Space" (later published in his book ''God's Glory in the Heavens'' (1862)) as a humorous science fantasy story about a [[space gun]] launching a manned spacecraft equipped with rockets for landing on the Moon, but eventually used for another [[orbital maneuver]].\n\n * 1902 - French cinema pioneer [[Georges M\u00e9li\u00e8s]] directs ''[[A Trip to the Moon]]'', the first film about space travel.\n* 1903 - [[Konstantin Tsiolkovsky]] begins a series of papers discussing the use of [[rocket]]ry to reach outer space, [[space suit]]s, and colonization of the [[Solar System]]. Two key points discussed in his works are [[liquid fuel]]s and [[staging (rocketry)|staging]].\n* 1913 - Without knowing the work of Russian mathematician [[Konstantin Tsiolkovsky]], French engineer [[Robert Esnault-Pelterie]] derived the equations for space flight, produced a paper that presented the [[rocket equation]] and calculated the energies required to reach the Moon and nearby planets.<ref>"Considerations sur les resultats d'un allegement indefini des moteurs", ''Journal de physique theorique et appliquee'', Paris, 1913</ref>\n* 1916 - first use of rockets (with the solid fuel [[Le Prieur rocket]]) for both air-to-air attacks, and air to ground.<ref>{{cite book|last=Guttman|first=Jon|title=Balloon-busting aces of World War 1|url=https://archive.org/details/balloonbustingac01gutt|url-access=limited|series=Osprey aircraft of the aces 66|publisher=Osprey|location=Oxford, UK|year=2005|isbn=978-1841768779|page=[https://archive.org/details/balloonbustingac01gutt/page/n13 12]}}</ref>\n* 1922 - [[Hermann Oberth]] publishes his scientific work about rocketry and space exploration: ''Die Rakete zu den Planetenr\u00e4umen'' ("By Rocket into Planetary Space").\n* 1924 - [[Society for Studies of Interplanetary Travel]] founded in [[Moscow]] by Konstantin Tsiolkovsky, [[Friedrich Zander]] and 200 other space and rocket experts\n* 1926 - [[Robert Goddard (scientist)|Robert Goddard]] launches the first liquid fuel rocket. This is considered by some to be the start of the [[Space Age]].<ref>{{Cite web|title = Goddard launches space age with historic first 85 years ago today|url = http://www.clarku.edu/article/goddard-launches-space-age-historic-first-85-years-ago-today|access-date = 2019-07-28}}</ref>\n* 1927 - [[Verein f\u00fcr Raumschiffahrt]] (VfR - "Spaceflight Society") founded in Germany.\n* 1928 - World's first large-scale rocket program, [[Opel RAK]] initiated by [[Max Valier]] and [[Fritz von Opel]], achieving speed records for ground and rail vehicles in 1928<ref>https://www.airforcemag.com/article/0904rocket/ article by Walter J. Boyne in Air Force Magazine, September 1, 2004 </ref> \n* 1929 - Opel RAK head of rocket technology [[Friedrich Wilhelm Sander]] laucnches two liquid-fuel rockets on April 10 and 12, 1929 as of 21 cm in diameter and with a length of 74 cm,  weighing 7 kg empty and 16 kg with fuel, maximum thrust was 45 to 50 kp, total burning time 132 seconds.\n* 1929 - World's first public flight of a manned rocket plane, [[Opel RAK.1]], piloted by [[Fritz von Opel]] on September 30, 1929<ref>https://www.airforcemag.com/article/0904rocket/ article by Walter J. Boyne in Air Force Magazine, September 1, 2004 </ref>\n* 1929 - ''[[Woman in the Moon]]'', considered to be one of the first "serious" science fiction films.\n* 1931 - [[Friedrich Schmiedl]] attempts the first [[rocket mail]] service in [[Austria]] \n*1933 - [[Sergei Korolev]] and [[Mikhail Tikhonravov]] launch the first liquid-fueled rocket in the [[Soviet Union]]<ref name=":0">{{Cite web|url=https://www.britannica.com/science/space-exploration|title=space exploration {{!}} History, Definition, & Facts|website=Encyclopedia Britannica|language=en|access-date=2019-07-06}}</ref> \n* 1935 - [[Emilio Herrera Linares]] from [[Spain]] designed and made the first full-pressured astronaut suit, called the escafandra estraton\u00e1utica. The Russians then used a model of Herrera's suit when first flying into space of which the Americans would then later adopt when creating their own space program\n*1936 - Research on rockets begins at the [[Guggenheim Aeronautical Laboratory]] at the [[California Institute of Technology]] (GALCIT), the predecessor to the [[Jet Propulsion Laboratory]], under the direction of [[Frank Malina]] and [[Theodore von K\u00e1rm\u00e1n]]<ref name=":0" /> \n* 1937 - [[Peenem\u00fcnde Army Research Center]] founded in Germany\n* 1938 - The Projectile Development Establishment founded at [[Fort Halstead]] for the [[United Kingdom]]'s research into military [[Solid-propellant rocket|solid-fuel rockets]].\n* 1939 - [[Katyusha rocket launcher|Katyusha]] multiple rocket launchers ({{Lang-ru|\u041a\u0430\u0442\u044e\u0448\u0430}}) are a type of [[rocket artillery]] first built and fielded by the [[Soviet Union]].\n* 1941 -  French rocket [[EA-41 (rocket)|EA-41]] is launched, being the first European [[Rocket propellant|liquid propellant]] working rocket<ref>{{cite web|url=http://www.capcomespace.net/dossiers/espace_europeen/ariane/index.htm|title=Sommaire chronologie Ariane|website=Capcomespace.net|access-date=11 August 2017}}</ref> (It was, however, preceded by the Peenemunde A5 and Soviet experiments.)\n* 1941 - Jet Assisted Take Off [[JATO]] installed on US Army Air Corp [[ERCO Ercoupe|Ercoupe]] aircraft occurred on 12 August in March Field, California.\n* 1942 - [[Wernher von Braun]] and [[Walter Dornberger]] launch the first [[V-2 rocket]] at [[Peenem\u00fcnde]] in northern Germany.\n* 1942 - A V-2 rocket reaches an altitude of 85 km.\n* 1944 - The V-2 rocket [[MW 18014]] reaches an altitude of 176 km, becoming the first man-made object in [[Outer space|space]].\n* 1945 - [[Lothar Sieber]] dies after the first vertical take-off manned rocket flight in a [[Bachem Ba 349]] "Natter"\n* 1945 - [[Operation Paperclip]] takes 1,600 German rocket scientists and technicians to the United States\n* 1945 - [[Operation Osoaviakhim]] takes 2,000 German rocket scientists and technicians to the Soviet Union\n* 1946 - First flight of the [[Nike missile]], later the first operational [[Surface-to-air missile|surface-to-air guided missile]]\n* 1947 - [[Chuck Yeager]] achieves the first manned [[supersonic]] flight in a [[Bell X-1]] rocket-powered aircraft\n* 1949 - [[Willy Ley]] publishes ''The Conquest of Space''\n* 1952 - 22 May, French [[V\u00e9ronique (rocket)|V\u00e9ronique 1]] rocket is launched from the [[French Algeria|Algerian desert]].\n* 1952 - Wernher von Braun discusses the technical details of a manned exploration of [[Mars]] in ''[[Das Marsprojekt]]''.\n* 1953 - ''Colliers'' magazine publishes a series of articles on man's future in space, igniting the interest of people around the world. The series includes numerous articles by Ley and von Braun, illustrated by Chesley Bonestell.\n* 1956 - First launch of [[PGM-17 Thor]], the first US ballistic missile and forerunner of the [[Delta (rocket family)|Delta space launch rockets]]\n* 1957 - Launch of the first [[ICBM]], the [[Soviet Union|USSR]]'s [[R-7 rocket|R-7 (8K71)]], known to [[NATO]] as the SS-6 ''Sapwood''.\n* 1957 - The USSR launches [[Sputnik 1]], the first artificial satellite.\n* 1958 - The U.S. launches [[Explorer 1]], the first American artificial satellite, on a [[Jupiter-C]] rocket.\n* 1958 - US launches their first ICBM, the [[Atlas (missile)|Atlas]]-B (the Atlas-A was a test article only).\n* 1961 - the USSR launches [[Vostok 1]], [[Yuri Gagarin]] reached a height of 327 km above Earth and was the first man to orbit Earth.\n* 1961 - US, a [[Mercury program|Mercury]] capsule named ''[[Freedom 7]]'' with [[Alan Shepard|Alan B. Shepard]], spacecraft was launched by a [[Redstone (rocket)|Redstone rocket]] on a ballistic trajectory [[suborbital flight]]. It was the first human space mission that landed with pilot still in spacecraft, thus the first complete human spaceflight by [[F\u00e9d\u00e9ration A\u00e9ronautique Internationale|FAI]] definitions.<ref>{{cite web |last1=Garmon |first1=Jay |title=Geek Trivia: A leap of fakes |url=http://www.techrepublic.com/article/geek-trivia-a-leap-of-fakes |website=TechRepublic |access-date=28 July 2019 |language=en}}</ref>\n* 1962 - The US launches Mercury MA-6 (''[[Friendship 7]]'') on an [[Atlas (rocket family)|Atlas D]] booster, [[John Glenn]] puts America in orbit.\n*1962 - [[Pakistan]] launched [[Rehbar-I]] and was the first country in [[Islamic world]] to successfully launch a vessel in outer space.\n* 1963 - The USSR launches [[Vostok 6]], [[Valentina Tereshkova]] was the first woman (and first civilian) to orbit Earth. She remained in space for nearly three days and orbited the Earth 48 times.\n* 1963 - US [[X-15]] rocket-plane, the first reusable manned spacecraft (suborbital) reaches space, pioneering reusability, carried launch and glide landings.\n* 1965 - USSR Proton rocket, highly successful launch vehicle with notable payloads, Salyut 6 and Salyut 7, Mir, and ISS components\n* 1965 - Robert Salked investigates various single stage to orbit spaceplane concepts<ref>{{cite web|url=http://www.astronautix.com/craft/saluttle.htm|title=Salkeld Shuttle|publisher=Astronautix.com|access-date=30 November 2014}}</ref><ref>{{cite web|url=http://www.pmview.com/spaceodysseytwo/spacelvs/sld039.htm|title=ROBERT SALKELD'S|publisher=Pmview.com|access-date=30 November 2014}}</ref><ref>{{cite web|url=https://history.nasa.gov/sts25th/printFriendly/further.html|title=STS-1 Further Reading|publisher=History.nasa.gov|access-date=30 November 2014}}</ref>\n* 1965 - FR [[Diamant (rocket)|Diamant]], first French and European rocket to reach the orbit, France became the third space nation.<ref>https://presse.cnes.fr/en/cnes-celebrates-diamants-50th-anniversary-origins-frances-independence-space</ref>\n* 1966 - USSR [[Luna 9]], the first soft landing on the [[Moon]]\n* 1966 - USSR launches [[Soyuz spacecraft]], longest-running series of spacecraft, eventually serving Soviet, Russian and International space missions.\n* 1968 - USSR [[Zond 5]], two tortoises and smaller biological Earthlings circle the Moon and return safely to Earth.\n* 1968 - US [[Apollo 8]], the first men to reach and orbit the Moon.\n* 1969 - US [[Apollo 11]], first men on the Moon, first lunar surface extravehicular activity.\n* 1975 - EU [[ESA]], creation of the European Space Agency.<ref>https://www.esa.int/About_Us/ESA_history/History_of_Europe_in_space</ref>\n* 1979 - EU [[Ariane 1]], first Ariane European rocket.<ref>https://www.arianespace.com/company-milestones/decades/1970/</ref>\n* 1980 - EU [[Arianespace]], creation of Arianespace, world first commercial space transportation company. <ref>https://www.arianespace.com/company-milestones/decades/1980/#timeline-year-1980</ref>\n* 1981 - US [[Space Shuttle]] pioneers reusability and glide landings\n* 1988 - EU [[Ariane 4]], first launch of the Ariane 4 rocket.<ref>https://www.arianespace.com/company-milestones/decades/1980/#timeline-year-1988</ref>\n* 1996 - EU [[Ariane 5]], first flight of the Ariane 5 rocket, self-destructed in flight. After that, Ariane 5 will be the main European rocket for decades.<ref>https://videotheque.cnes.fr/index.php?urlaction=doc&id_doc=16001&rang=1</ref>\n* 1998 - US [[Deep Space 1]] is first deep space mission to use an [[ion thruster]] for propulsion.\n* 1998 - Russia launch [[Zarya]] module which is the first part of the [[International Space Station]].\n\n * 2001 - Russian [[Soyuz spacecraft]] sent the first space tourist [[Dennis Tito]] to [[International Space Station]].<ref>{{cite web|url=http://www.redorbit.com/news/space/65010/first_space_tourist_dennis_tito_to_make_business_visit_to/index.html |title=First Space Tourist Dennis Tito to Make Business Visit to Russia |date=June 15, 2004 |publisher=redOrbit |access-date=February 27, 2013 |url-status=unfit |archive-url=https://web.archive.org/web/20101127161905/http://www.redorbit.com/news/space/65010/first_space_tourist_dennis_tito_to_make_business_visit_to/index.html |archive-date=November 27, 2010 }}</ref>\n* 2004 - US-based, first privately developed, manned (suborbital) spaceflight, [[SpaceShipOne]] demonstrates reusability.<ref name=ft>{{Cite web|url=http://www.scaled.com/projects/tierone/combined_white_knight_spaceshipone_flight_tests|title=SpaceShipOne Flight Tests|work=Scaled Composites|url-status=dead|archive-url=https://web.archive.org/web/20100822194232/http://www.scaled.com/projects/tierone/combined_white_knight_spaceshipone_flight_tests|archive-date=2010-08-22}}</ref>\n* 2008 - [[SpaceX]]\u2014with their [[Falcon 1]] rocket\u2014became the first [[private spaceflight|private entity]] to successfully launch a [[launch vehicle|rocket]] into [[orbital spaceflight|orbit]].<ref name=sfn20080928>\n{{cite web |last=Clark|first=Stephen |title=Sweet Success at Last for Falcon 1 Rocket |date=2008-09-28 |work=Spaceflight Now |url=http://www.spaceflightnow.com/falcon/004/index.html |access-date=2014-11-30 |quote=''the first privately developed liquid-fueled rocket to successfully reach orbit.''}}</ref>\n* 2012 - The [[SpaceX Dragon]] [[space capsule]]\u2014launched aboard a [[Falcon 9 v1.0|Falcon 9]] launch vehicle\u2014was the first private [[spacecraft]] to successfully dock with another spacecraft, and was also the first private capsule to dock at the [[International Space Station]].<ref name=sfn2012>\n{{cite web |last=Clark |first=Stephen |title=First commercial cargo ship arrives at space station |url=http://spaceflightnow.com/falcon9/003/120525arrival/ |access-date=30 November 2014 |work=Spaceflight Now |date=25 May 2012 |archive-url=https://web.archive.org/web/20120529031450/http://www.spaceflightnow.com/falcon9/003/120525arrival/ |archive-date=29 May 2012 |url-status=dead }}</ref>\n* 2014 - First booster rocket returning from an [[orbital spaceflight|orbital trajectory]] to achieve a zero-velocity-at-zero-altitude [[Rocket propulsion|propulsive]] [[VTVL|vertical landing]].  The first-stage booster of [[Falcon 9 Flight 9]] made the first successful controlled ocean soft touchdown of a liquid-rocket-engine orbital booster on April 18, 2014.<ref name=mit20140422>\n{{cite news |last=Belfiore|first=Michael |title=SpaceX Brings a Booster Safely Back to Earth |url=http://www.technologyreview.com/news/526806/spacex-brings-a-booster-safely-back-to-earth/ |access-date=April 25, 2014 |newspaper=MIT Technology Review |date=April 22, 2014 }}</ref><ref name=bi20141125>\n{{cite news |last1=Orwig|first1=Jessica |title=Elon Musk Just Unveiled A Game-Changing Ocean Landing Pad For His Reusable Rockets |url=http://www.businessinsider.com/elon-musk-rockets-that-land-at-sea-2014-11 |access-date=2014-12-11 |work=Business Insider |date=2014-11-25 |quote=''The first successful "soft landing" of a Falcon 9 rocket happened in April of this year'' }}</ref>\n* 2015 - [[SpaceX]]'s [[Falcon 9 Flight 20]] was the first time that the first stage of an orbital rocket made a successful return and [[VTVL|vertical landing]].<ref name=sn20151221>{{cite news |author=Jeff Foust |title=Falcon 9 Launches Orbcomm Satellites, Lands First Stage |url=http://spacenews.com/falcon-9-launches-orbcomm-satellites-first-stage-lands/ |work=SpaceNews |date=December 21, 2015 |access-date=2015-12-22 |quote=''the first time SpaceX had successfully landed the rocket's first stage.'' }}</ref>\n* 2017 - [[SpaceX]]'s [[Falcon 9]] [[SES-10]] was the first time a used orbital rocket made a successful return<ref>{{cite web|url=http://spacenews.com/spacex-demonstrates-rocket-reusability-with-ses-10-launch-and-booster-landing/|title=SpaceX demonstrates rocket reusability with SES-10 launch and booster landing|date=30 March 2017|website=Spacenews.com|access-date=11 August 2017}}</ref>\n* 2018 - The [[Electron (rocket)|Electron]] rocket was the first New-Zealand rocket to achieve orbit. The rocket is also unique in using an [[electric pump-fed engine]]. The rocket also carried an additional satellite payload called "[[Humanity Star]]", a 1-meter-wide (3 ft) carbon fiber sphere made up of 65 panels that reflect the Sun's light.<ref name="tv20180124">{{cite news |url=https://www.theverge.com/2018/1/24/16926426/rocket-lab-humanity-star-secret-satellite-electron-test-launch |title=Rocket Lab secretly launched a disco ball satellite on its latest test flight |work=[[The Verge]] |last=Grush |first=Loren |date=24 January 2018 |access-date=24 January 2018}}</ref>\n*2020 - [[SpaceX]]'s [[SpaceX Dragon|Dragon capsule]], rode on the [[Falcon 9]] rocket whilst carrying crew aboard, marking the first time astronauts have been sent to space via a private company.\n\n* [[History of rockets]]\n* [[List of missiles]]\n* [[Lists of rockets]]\n* [[Timeline of heat engine technology]]\n\n {{Reflist}}\n\n{{Spaceflight lists and timelines}}\n\n{{DEFAULTSORT:Timeline Of Rocket And Missile Technology}}", "Timeline of rocket and missile technology --- Introduction ---|11th century": "* 11th century AD - The first documented record of [[gunpowder]] and the [[fire arrow]], an early form of rocketry, appears in the Chinese text ''[[Wujing Zongyao]]''.", "Timeline of rocket and missile technology --- Introduction ---|17th century-19th century": "* 1633 - [[Lag\u00e2ri Hasan \u00c7elebi]] launched a 7-winged rocket using 50 okka (140 lbs) of gunpowder from Sarayburnu, the point below [[Topkap\u0131 Palace]] in [[Istanbul]].<ref name="refLAGARI">Winter, Frank H. (1992). "Who First Flew in a Rocket?", Journal of the British Interplanetary Society 45 (July 1992), p. 275-80</ref>\n* 1650 - ''Artis Magnae Artilleriae pars prima'' ("Great Art of Artillery, the First Part") is printed in Amsterdam, about a year before the death of its author, [[Kazimierz Siemienowicz]].\n* 1664 - A "space rocket" is imagined as a future technology to be studied in France and its drawing is ordered by [[France|French]] finance minister [[Jean-Baptiste Colbert|Colbert]]; designed by [[Charles Le Brun|Le Brun]] on a [[Gobelins manufactory|Gobelins]] tapestry<ref>{{cite web|url=https://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1972x006x004/HSMx1972x006x004x0250.pdf|archive-url=https://web.archive.org/web/20190426061726/https://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1972x006x004/HSMx1972x006x004x0250.pdf|url-status=dead|archive-date=2019-04-26|title=Astronautique|author=Jean Cheymol|website=Biusante.parisdescartes.fr|access-date=2017-08-11}}</ref> (see: [[French space program]])\n* 1798 - [[Tipu Sultan]], the King of the state of [[Mysore]] in India, develops and uses iron rockets against the British Army (see [[Mysorean rockets]]).\n* 1801 - The British Army develops the [[Congreve rocket]] based on weapons used against them by [[Tipu Sultan]].\n* 1806 - [[Claude Ruggieri]], an Italian living in France, launched animals on rockets and recovered them using parachutes. He was prevented from launching a child by police.<ref>{{cite web|url=http://history.msfc.nasa.gov/rocketry/14.html|archive-url=https://web.archive.org/web/20010215015030/http://history.msfc.nasa.gov/rocketry/14.html|url-status=dead|archive-date=15 February 2001|title=MSFC History OFFICE: CLAUDE RUGGIERI|publisher=History.msfc.nasa.gov|access-date=30 November 2014}}</ref>\n* 1813 - "A Treatise on the Motion of Rockets" by [[William Moore (British mathematician)|William Moore]] \u2013 first appearance of the [[rocket equation]]\n* 1818 - [[Henry Trengrouse]] demonstrates his rocket apparatus for projecting a lifeline from a wrecked ship to the shore, later widely adopted\n* 1844 - [[William Hale (British inventor)|William Hale]] invents the [[Spin-stabilisation|spin-stabilized]] rocket\n* 1861 - [[William Leitch (scientist)|William Leitch]] publishes an essay "A Journey Through Space" (later published in his book ''God's Glory in the Heavens'' (1862)) as a humorous science fantasy story about a [[space gun]] launching a manned spacecraft equipped with rockets for landing on the Moon, but eventually used for another [[orbital maneuver]].", "Timeline of rocket and missile technology --- Introduction ---|20th century": "* 1902 - French cinema pioneer [[Georges M\u00e9li\u00e8s]] directs ''[[A Trip to the Moon]]'', the first film about space travel.\n* 1903 - [[Konstantin Tsiolkovsky]] begins a series of papers discussing the use of [[rocket]]ry to reach outer space, [[space suit]]s, and colonization of the [[Solar System]]. Two key points discussed in his works are [[liquid fuel]]s and [[staging (rocketry)|staging]].\n* 1913 - Without knowing the work of Russian mathematician [[Konstantin Tsiolkovsky]], French engineer [[Robert Esnault-Pelterie]] derived the equations for space flight, produced a paper that presented the [[rocket equation]] and calculated the energies required to reach the Moon and nearby planets.<ref>"Considerations sur les resultats d'un allegement indefini des moteurs", ''Journal de physique theorique et appliquee'', Paris, 1913</ref>\n* 1916 - first use of rockets (with the solid fuel [[Le Prieur rocket]]) for both air-to-air attacks, and air to ground.<ref>{{cite book|last=Guttman|first=Jon|title=Balloon-busting aces of World War 1|url=https://archive.org/details/balloonbustingac01gutt|url-access=limited|series=Osprey aircraft of the aces 66|publisher=Osprey|location=Oxford, UK|year=2005|isbn=978-1841768779|page=[https://archive.org/details/balloonbustingac01gutt/page/n13 12]}}</ref>\n* 1922 - [[Hermann Oberth]] publishes his scientific work about rocketry and space exploration: ''Die Rakete zu den Planetenr\u00e4umen'' ("By Rocket into Planetary Space").\n* 1924 - [[Society for Studies of Interplanetary Travel]] founded in [[Moscow]] by Konstantin Tsiolkovsky, [[Friedrich Zander]] and 200 other space and rocket experts\n* 1926 - [[Robert Goddard (scientist)|Robert Goddard]] launches the first liquid fuel rocket. This is considered by some to be the start of the [[Space Age]].<ref>{{Cite web|title = Goddard launches space age with historic first 85 years ago today|url = http://www.clarku.edu/article/goddard-launches-space-age-historic-first-85-years-ago-today|access-date = 2019-07-28}}</ref>\n* 1927 - [[Verein f\u00fcr Raumschiffahrt]] (VfR - "Spaceflight Society") founded in Germany.\n* 1928 - World's first large-scale rocket program, [[Opel RAK]] initiated by [[Max Valier]] and [[Fritz von Opel]], achieving speed records for ground and rail vehicles in 1928<ref>https://www.airforcemag.com/article/0904rocket/ article by Walter J. Boyne in Air Force Magazine, September 1, 2004 </ref> \n* 1929 - Opel RAK head of rocket technology [[Friedrich Wilhelm Sander]] laucnches two liquid-fuel rockets on April 10 and 12, 1929 as of 21 cm in diameter and with a length of 74 cm,  weighing 7 kg empty and 16 kg with fuel, maximum thrust was 45 to 50 kp, total burning time 132 seconds.\n* 1929 - World's first public flight of a manned rocket plane, [[Opel RAK.1]], piloted by [[Fritz von Opel]] on September 30, 1929<ref>https://www.airforcemag.com/article/0904rocket/ article by Walter J. Boyne in Air Force Magazine, September 1, 2004 </ref>\n* 1929 - ''[[Woman in the Moon]]'', considered to be one of the first "serious" science fiction films.\n* 1931 - [[Friedrich Schmiedl]] attempts the first [[rocket mail]] service in [[Austria]] \n*1933 - [[Sergei Korolev]] and [[Mikhail Tikhonravov]] launch the first liquid-fueled rocket in the [[Soviet Union]]<ref name=":0">{{Cite web|url=https://www.britannica.com/science/space-exploration|title=space exploration {{!}} History, Definition, & Facts|website=Encyclopedia Britannica|language=en|access-date=2019-07-06}}</ref> \n* 1935 - [[Emilio Herrera Linares]] from [[Spain]] designed and made the first full-pressured astronaut suit, called the escafandra estraton\u00e1utica. The Russians then used a model of Herrera's suit when first flying into space of which the Americans would then later adopt when creating their own space program\n*1936 - Research on rockets begins at the [[Guggenheim Aeronautical Laboratory]] at the [[California Institute of Technology]] (GALCIT), the predecessor to the [[Jet Propulsion Laboratory]], under the direction of [[Frank Malina]] and [[Theodore von K\u00e1rm\u00e1n]]<ref name=":0" /> \n* 1937 - [[Peenem\u00fcnde Army Research Center]] founded in Germany\n* 1938 - The Projectile Development Establishment founded at [[Fort Halstead]] for the [[United Kingdom]]'s research into military [[Solid-propellant rocket|solid-fuel rockets]].\n* 1939 - [[Katyusha rocket launcher|Katyusha]] multiple rocket launchers ({{Lang-ru|\u041a\u0430\u0442\u044e\u0448\u0430}}) are a type of [[rocket artillery]] first built and fielded by the [[Soviet Union]].\n* 1941 -  French rocket [[EA-41 (rocket)|EA-41]] is launched, being the first European [[Rocket propellant|liquid propellant]] working rocket<ref>{{cite web|url=http://www.capcomespace.net/dossiers/espace_europeen/ariane/index.htm|title=Sommaire chronologie Ariane|website=Capcomespace.net|access-date=11 August 2017}}</ref> (It was, however, preceded by the Peenemunde A5 and Soviet experiments.)\n* 1941 - Jet Assisted Take Off [[JATO]] installed on US Army Air Corp [[ERCO Ercoupe|Ercoupe]] aircraft occurred on 12 August in March Field, California.\n* 1942 - [[Wernher von Braun]] and [[Walter Dornberger]] launch the first [[V-2 rocket]] at [[Peenem\u00fcnde]] in northern Germany.\n* 1942 - A V-2 rocket reaches an altitude of 85 km.\n* 1944 - The V-2 rocket [[MW 18014]] reaches an altitude of 176 km, becoming the first man-made object in [[Outer space|space]].\n* 1945 - [[Lothar Sieber]] dies after the first vertical take-off manned rocket flight in a [[Bachem Ba 349]] "Natter"\n* 1945 - [[Operation Paperclip]] takes 1,600 German rocket scientists and technicians to the United States\n* 1945 - [[Operation Osoaviakhim]] takes 2,000 German rocket scientists and technicians to the Soviet Union\n* 1946 - First flight of the [[Nike missile]], later the first operational [[Surface-to-air missile|surface-to-air guided missile]]\n* 1947 - [[Chuck Yeager]] achieves the first manned [[supersonic]] flight in a [[Bell X-1]] rocket-powered aircraft\n* 1949 - [[Willy Ley]] publishes ''The Conquest of Space''\n* 1952 - 22 May, French [[V\u00e9ronique (rocket)|V\u00e9ronique 1]] rocket is launched from the [[French Algeria|Algerian desert]].\n* 1952 - Wernher von Braun discusses the technical details of a manned exploration of [[Mars]] in ''[[Das Marsprojekt]]''.\n* 1953 - ''Colliers'' magazine publishes a series of articles on man's future in space, igniting the interest of people around the world. The series includes numerous articles by Ley and von Braun, illustrated by Chesley Bonestell.\n* 1956 - First launch of [[PGM-17 Thor]], the first US ballistic missile and forerunner of the [[Delta (rocket family)|Delta space launch rockets]]\n* 1957 - Launch of the first [[ICBM]], the [[Soviet Union|USSR]]'s [[R-7 rocket|R-7 (8K71)]], known to [[NATO]] as the SS-6 ''Sapwood''.\n* 1957 - The USSR launches [[Sputnik 1]], the first artificial satellite.\n* 1958 - The U.S. launches [[Explorer 1]], the first American artificial satellite, on a [[Jupiter-C]] rocket.\n* 1958 - US launches their first ICBM, the [[Atlas (missile)|Atlas]]-B (the Atlas-A was a test article only).\n* 1961 - the USSR launches [[Vostok 1]], [[Yuri Gagarin]] reached a height of 327 km above Earth and was the first man to orbit Earth.\n* 1961 - US, a [[Mercury program|Mercury]] capsule named ''[[Freedom 7]]'' with [[Alan Shepard|Alan B. Shepard]], spacecraft was launched by a [[Redstone (rocket)|Redstone rocket]] on a ballistic trajectory [[suborbital flight]]. It was the first human space mission that landed with pilot still in spacecraft, thus the first complete human spaceflight by [[F\u00e9d\u00e9ration A\u00e9ronautique Internationale|FAI]] definitions.<ref>{{cite web |last1=Garmon |first1=Jay |title=Geek Trivia: A leap of fakes |url=http://www.techrepublic.com/article/geek-trivia-a-leap-of-fakes |website=TechRepublic |access-date=28 July 2019 |language=en}}</ref>\n* 1962 - The US launches Mercury MA-6 (''[[Friendship 7]]'') on an [[Atlas (rocket family)|Atlas D]] booster, [[John Glenn]] puts America in orbit.\n*1962 - [[Pakistan]] launched [[Rehbar-I]] and was the first country in [[Islamic world]] to successfully launch a vessel in outer space.\n* 1963 - The USSR launches [[Vostok 6]], [[Valentina Tereshkova]] was the first woman (and first civilian) to orbit Earth. She remained in space for nearly three days and orbited the Earth 48 times.\n* 1963 - US [[X-15]] rocket-plane, the first reusable manned spacecraft (suborbital) reaches space, pioneering reusability, carried launch and glide landings.\n* 1965 - USSR Proton rocket, highly successful launch vehicle with notable payloads, Salyut 6 and Salyut 7, Mir, and ISS components\n* 1965 - Robert Salked investigates various single stage to orbit spaceplane concepts<ref>{{cite web|url=http://www.astronautix.com/craft/saluttle.htm|title=Salkeld Shuttle|publisher=Astronautix.com|access-date=30 November 2014}}</ref><ref>{{cite web|url=http://www.pmview.com/spaceodysseytwo/spacelvs/sld039.htm|title=ROBERT SALKELD'S|publisher=Pmview.com|access-date=30 November 2014}}</ref><ref>{{cite web|url=https://history.nasa.gov/sts25th/printFriendly/further.html|title=STS-1 Further Reading|publisher=History.nasa.gov|access-date=30 November 2014}}</ref>\n* 1965 - FR [[Diamant (rocket)|Diamant]], first French and European rocket to reach the orbit, France became the third space nation.<ref>https://presse.cnes.fr/en/cnes-celebrates-diamants-50th-anniversary-origins-frances-independence-space</ref>\n* 1966 - USSR [[Luna 9]], the first soft landing on the [[Moon]]\n* 1966 - USSR launches [[Soyuz spacecraft]], longest-running series of spacecraft, eventually serving Soviet, Russian and International space missions.\n* 1968 - USSR [[Zond 5]], two tortoises and smaller biological Earthlings circle the Moon and return safely to Earth.\n* 1968 - US [[Apollo 8]], the first men to reach and orbit the Moon.\n* 1969 - US [[Apollo 11]], first men on the Moon, first lunar surface extravehicular activity.\n* 1975 - EU [[ESA]], creation of the European Space Agency.<ref>https://www.esa.int/About_Us/ESA_history/History_of_Europe_in_space</ref>\n* 1979 - EU [[Ariane 1]], first Ariane European rocket.<ref>https://www.arianespace.com/company-milestones/decades/1970/</ref>\n* 1980 - EU [[Arianespace]], creation of Arianespace, world first commercial space transportation company. <ref>https://www.arianespace.com/company-milestones/decades/1980/#timeline-year-1980</ref>\n* 1981 - US [[Space Shuttle]] pioneers reusability and glide landings\n* 1988 - EU [[Ariane 4]], first launch of the Ariane 4 rocket.<ref>https://www.arianespace.com/company-milestones/decades/1980/#timeline-year-1988</ref>\n* 1996 - EU [[Ariane 5]], first flight of the Ariane 5 rocket, self-destructed in flight. After that, Ariane 5 will be the main European rocket for decades.<ref>https://videotheque.cnes.fr/index.php?urlaction=doc&id_doc=16001&rang=1</ref>\n* 1998 - US [[Deep Space 1]] is first deep space mission to use an [[ion thruster]] for propulsion.\n* 1998 - Russia launch [[Zarya]] module which is the first part of the [[International Space Station]].", "Timeline of rocket and missile technology --- Introduction ---|21st century": "* 2001 - Russian [[Soyuz spacecraft]] sent the first space tourist [[Dennis Tito]] to [[International Space Station]].<ref>{{cite web|url=http://www.redorbit.com/news/space/65010/first_space_tourist_dennis_tito_to_make_business_visit_to/index.html |title=First Space Tourist Dennis Tito to Make Business Visit to Russia |date=June 15, 2004 |publisher=redOrbit |access-date=February 27, 2013 |url-status=unfit |archive-url=https://web.archive.org/web/20101127161905/http://www.redorbit.com/news/space/65010/first_space_tourist_dennis_tito_to_make_business_visit_to/index.html |archive-date=November 27, 2010 }}</ref>\n* 2004 - US-based, first privately developed, manned (suborbital) spaceflight, [[SpaceShipOne]] demonstrates reusability.<ref name=ft>{{Cite web|url=http://www.scaled.com/projects/tierone/combined_white_knight_spaceshipone_flight_tests|title=SpaceShipOne Flight Tests|work=Scaled Composites|url-status=dead|archive-url=https://web.archive.org/web/20100822194232/http://www.scaled.com/projects/tierone/combined_white_knight_spaceshipone_flight_tests|archive-date=2010-08-22}}</ref>\n* 2008 - [[SpaceX]]\u2014with their [[Falcon 1]] rocket\u2014became the first [[private spaceflight|private entity]] to successfully launch a [[launch vehicle|rocket]] into [[orbital spaceflight|orbit]].<ref name=sfn20080928>\n{{cite web |last=Clark|first=Stephen |title=Sweet Success at Last for Falcon 1 Rocket |date=2008-09-28 |work=Spaceflight Now |url=http://www.spaceflightnow.com/falcon/004/index.html |access-date=2014-11-30 |quote=''the first privately developed liquid-fueled rocket to successfully reach orbit.''}}</ref>\n* 2012 - The [[SpaceX Dragon]] [[space capsule]]\u2014launched aboard a [[Falcon 9 v1.0|Falcon 9]] launch vehicle\u2014was the first private [[spacecraft]] to successfully dock with another spacecraft, and was also the first private capsule to dock at the [[International Space Station]].<ref name=sfn2012>\n{{cite web |last=Clark |first=Stephen |title=First commercial cargo ship arrives at space station |url=http://spaceflightnow.com/falcon9/003/120525arrival/ |access-date=30 November 2014 |work=Spaceflight Now |date=25 May 2012 |archive-url=https://web.archive.org/web/20120529031450/http://www.spaceflightnow.com/falcon9/003/120525arrival/ |archive-date=29 May 2012 |url-status=dead }}</ref>\n* 2014 - First booster rocket returning from an [[orbital spaceflight|orbital trajectory]] to achieve a zero-velocity-at-zero-altitude [[Rocket propulsion|propulsive]] [[VTVL|vertical landing]].  The first-stage booster of [[Falcon 9 Flight 9]] made the first successful controlled ocean soft touchdown of a liquid-rocket-engine orbital booster on April 18, 2014.<ref name=mit20140422>\n{{cite news |last=Belfiore|first=Michael |title=SpaceX Brings a Booster Safely Back to Earth |url=http://www.technologyreview.com/news/526806/spacex-brings-a-booster-safely-back-to-earth/ |access-date=April 25, 2014 |newspaper=MIT Technology Review |date=April 22, 2014 }}</ref><ref name=bi20141125>\n{{cite news |last1=Orwig|first1=Jessica |title=Elon Musk Just Unveiled A Game-Changing Ocean Landing Pad For His Reusable Rockets |url=http://www.businessinsider.com/elon-musk-rockets-that-land-at-sea-2014-11 |access-date=2014-12-11 |work=Business Insider |date=2014-11-25 |quote=''The first successful "soft landing" of a Falcon 9 rocket happened in April of this year'' }}</ref>\n* 2015 - [[SpaceX]]'s [[Falcon 9 Flight 20]] was the first time that the first stage of an orbital rocket made a successful return and [[VTVL|vertical landing]].<ref name=sn20151221>{{cite news |author=Jeff Foust |title=Falcon 9 Launches Orbcomm Satellites, Lands First Stage |url=http://spacenews.com/falcon-9-launches-orbcomm-satellites-first-stage-lands/ |work=SpaceNews |date=December 21, 2015 |access-date=2015-12-22 |quote=''the first time SpaceX had successfully landed the rocket's first stage.'' }}</ref>\n* 2017 - [[SpaceX]]'s [[Falcon 9]] [[SES-10]] was the first time a used orbital rocket made a successful return<ref>{{cite web|url=http://spacenews.com/spacex-demonstrates-rocket-reusability-with-ses-10-launch-and-booster-landing/|title=SpaceX demonstrates rocket reusability with SES-10 launch and booster landing|date=30 March 2017|website=Spacenews.com|access-date=11 August 2017}}</ref>\n* 2018 - The [[Electron (rocket)|Electron]] rocket was the first New-Zealand rocket to achieve orbit. The rocket is also unique in using an [[electric pump-fed engine]]. The rocket also carried an additional satellite payload called "[[Humanity Star]]", a 1-meter-wide (3 ft) carbon fiber sphere made up of 65 panels that reflect the Sun's light.<ref name="tv20180124">{{cite news |url=https://www.theverge.com/2018/1/24/16926426/rocket-lab-humanity-star-secret-satellite-electron-test-launch |title=Rocket Lab secretly launched a disco ball satellite on its latest test flight |work=[[The Verge]] |last=Grush |first=Loren |date=24 January 2018 |access-date=24 January 2018}}</ref>\n*2020 - [[SpaceX]]'s [[SpaceX Dragon|Dragon capsule]], rode on the [[Falcon 9]] rocket whilst carrying crew aboard, marking the first time astronauts have been sent to space via a private company.\n\n* [[History of rockets]]\n* [[List of missiles]]\n* [[Lists of rockets]]\n* [[Timeline of heat engine technology]]"}},
{"article_title": "Timeline of materials technology", "pageid": "58742", "revid": "1047457785", "timestamp": "2021-09-30T23:51:08Z", "history_paths": [["Timeline of materials technology --- Introduction ---"], ["Timeline of materials technology --- Introduction ---", "BC"], ["Timeline of materials technology --- Introduction ---", "1st millennium"], ["Timeline of materials technology --- Introduction ---", "2nd millennium"]], "categories": ["technology timelines", "materials science"], "heading_tree": {"Timeline of materials technology --- Introduction ---": {"BC": {}, "1st millennium": {}, "2nd millennium": {"18th century": {}, "19th century": {}, "20th century": {}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Timeline of materials technology --- Introduction ---": "{{Short description|Tools}}\nMajor innovations in '''[[Materials science|materials technology]]'''\n{{Expand list|date=February 2011}}\n\n \n*28,000 BC \u2013 People wear beads, bracelets, and pendants<ref name=":0">{{Cite book|title=Volume Library 1|publisher=The Southwestern Company|year=2009}}</ref>\n*14,500 BC \u2013 First [[pottery]], made by the [[J\u014dmon period|J\u014dmon]] people of Japan.\n*[[6th millennium BC]] \u2013 [[Copper]] [[metallurgy]] is invented and copper is used for ornamentation (see [[Plo\u010dnik (archaeological site)|Plo\u010dnik]] article)\n*[[2nd millennium BC]] \u2013 [[Bronze]] is used for [[weapon]]s and [[armor]]\n*16th century BC \u2013 The [[Hittites]] develop crude [[History of ferrous metallurgy|iron metallurgy]]\n*13th century BC \u2013 Invention of [[steel]] when [[iron]] and [[charcoal]] are combined properly\n*10th century BC \u2013 [[Glass]] production begins in [[ancient Near East]]\n*[[1st millennium BC]] \u2013 [[Pewter]] beginning to be used in China and [[Egypt]]\n*1000 BC \u2013 The [[Phoenicia|Phoenicians]] introduce dyes made from the purple murex.<ref name=":0" />\n*3rd century BC \u2013 [[Wootz steel]], the first [[crucible steel]], is invented in [[History of India|ancient India]]\n*50s BC \u2013 Glassblowing techniques flourish in [[Phoenicia]]\n*20s BC \u2013 [[Rome|Roman]] [[architecture (built environment)|architect]] [[Vitruvius]] describes low-water-content method for mixing [[concrete]]\n\n *3rd century \u2013 [[Cast iron]] widely used in [[Han Dynasty]] China\n*300 \u2013 Greek alchemist Zomius, summarizing the work of Egyptian alchemists, describes arsenic and lead acetate<ref name=":0" />\n*4th century \u2013 [[Iron pillar of Delhi]] is the oldest surviving example of corrosion-resistant steel\n*8th century \u2013 [[Porcelain]] is invented in [[Tang Dynasty]] China\n*8th century \u2013 [[Tin-glazing]] of [[ceramic]]s invented by [[Alchemy and chemistry in Islam|Arabic chemists]] and [[Islamic pottery|potters]] in [[Basra]], [[Iraq]]<ref name=Mason>{{cite journal | last=Mason | first=Robert B. | title=New Looks at Old Pots: Results of Recent Multidisciplinary Studies of Glazed Ceramics from the Islamic World | journal=Muqarnas: Annual on Islamic Art and Architecture | year=1995 | volume=XII | pages=1\u201310 | publisher=Brill Academic Publishers | isbn=90-04-10314-7 | doi=10.2307/1523219| jstor=1523219 }}</ref>{{rp|1}}\n*9th century \u2013 [[Stoneware|Stonepaste ceramics]] invented in [[Iraq]]<ref name=Mason />{{rp|5}}\n*900 \u2013 First systematic classification of chemical substances appears in the works attributed to [[Jabir ibn Hayyan|J\u0101bir ibn \u1e24ayy\u0101n]] (Latin: Geber) and in those of the Persian alchemist and physician [[Abu Bakr al-Razi|Ab\u016b Bakr al-R\u0101z\u012b]] ({{circa}} 865\u2013925, Latin: Rhazes)<ref>{{Cite journal|last1=Karpenko|first1=Vladim\u00edr|last2=Norris|first2=John A.|year=2002|title=Vitriol in the History of Chemistry|journal=Chemick\u00e9 listy|volume=96|issue=12|pages=997\u20131005|url=http://www.chemicke-listy.cz/ojs3/index.php/chemicke-listy/article/view/2266}}</ref>\n*900 \u2013 [[Chemical synthesis|Synthesis]] of [[ammonium chloride]] from [[Organic compound|organic substances]] described in the works attributed to J\u0101bir ibn \u1e24ayy\u0101n (Latin: Geber)<ref>{{Cite book|last=Kraus|first=Paul|author-link=Paul Kraus (Arabist)|year=1942\u20131943|title=J\u00e2bir ibn Hayy\u00e2n: Contribution \u00e0 l'histoire des id\u00e9es scientifiques dans l'Islam. I. Le corpus des \u00e9crits j\u00e2biriens. II. J\u00e2bir et la science grecque|publisher=[[Institut Fran\u00e7ais d'Arch\u00e9ologie Orientale]]|location=Cairo|oclc=468740510|isbn=9783487091150}} Vol. II, pp. 41\u201342.</ref>\n*900 \u2013 Ab\u016b Bakr al-R\u0101z\u012b describes the preparation of plaster of Paris and metallic antimony<ref name=":0" />\n*9th century \u2013 [[Lustreware]] appears in Mesopotamia<ref>{{cite book|title=Ten thousand years of pottery |author=Emmanuel Cooper |publisher=University of Pennsylvania Press |edition=4th |date=2000 |isbn=0-8122-3554-1}}</ref>{{rp|86\u201387}}\n\n *1000 \u2013 Gunpowder is developed in China<ref name=":0" />\n*1340 \u2013 In [[Li\u00e8ge|Li\u00e8ge, Belgium]], the first blast furnaces for the production of iron are developed<ref name=":0" />\n*1448 \u2013 [[Johann Gutenberg]] develops [[type metal]] alloy\n*1450s \u2013 [[Cristallo]], a clear soda-based glass, is invented by [[Angelo Barovier]]\n*[[:Category:1540s in science|1540]] \u2013 [[Vannoccio Biringuccio]] publishes first systematic book on [[metallurgy]]\n*[[:Category:1550s in science|1556]] \u2013 [[Georg Agricola]]'s influential book on [[metallurgy]]\n*[[1590 in science|1590]] \u2013 Glass [[lens (optics)|lens]]es are developed in the Netherlands and used for the first time in [[microscope]]s and [[telescope]]s\n*1664 \u2013 In the pipes supplying water to the gardens at Versailles, cast iron is used<ref name=":0" />\n\n *1717 \u2013 [[Abraham Darby I|Abraham Darby]] makes iron with coke, a derivative of coal<ref name=":0" />\n*[[1738 in science|1738]] \u2013 Metallic [[zinc]] processed by [[distillation]] from [[calamine (mineral)|calamine]] and charcoal patented by [[William Champion (metallurgist)|William Champion]]\n*[[1740 in science|1740]]  \u2013 [[Crucible steel]] technique developed by [[Benjamin Huntsman]]\n*1774 \u2013 \n**Joseph Priestley discovers oxygen<ref name=":0" />\n**Johann Gottlieb Gahn discovers manganese<ref name=":0" />\n**Karl Wilhelm Scheele discovers chlorine<ref name=":0" />\n*[[1779 in science|1779]]  \u2013 Hydraulic cement ([[stucco]]) patented by [[Bryan Higgins]] for use as an exterior [[plaster]]\n*[[1799 in science|1799]]  \u2013 [[Acid]] [[battery (electricity)|battery]] made from copper/zinc by [[Alessandro Volta]]\n\n *[[1821 in science|1821]]  \u2013 [[Thermocouple]] invented by [[Thomas Johann Seebeck]]\n*[[1824 in science|1824]]  \u2013 [[Portland cement]] patent issued to [[Joseph Aspdin]]\n*[[1825 in science|1825]]  \u2013 Metallic [[aluminum]] produced by [[Hans Christian \u00d8rsted]]\n*[[1839 in science|1839]]  \u2013 [[Vulcanization|Vulcanized rubber]] invented by [[Charles Goodyear]]\n*[[1839 in science|1839]]  \u2013 [[Silver]]-based [[photography|photographic]] processes invented by [[Louis Daguerre]] and [[William Fox Talbot]]\n*[[1855 in science|1855]]  \u2013 [[Bessemer process]] for mass production of steel patented by [[Henry Bessemer]]\n*[[1861 in science|1861]]  \u2013 Color photography demonstrated by [[James Clerk Maxwell]]\n*[[1883 in science|1883]]  \u2013 First [[solar cell]]s using [[selenium]] waffles made by [[Charles Fritts]]\n*1893  \u2013 [[Exothermic welding|Thermite Welding]] developed and soon used to weld rails\n\n *[[1902 in science|1902]]  \u2013 [[Chemical synthesis|Synthetic]] [[ruby|rubies]] created by the [[Verneuil process]] developed by [[Auguste Verneuil]]\n*[[1908 in science|1908]]  \u2013 [[Cellophane]] invented by [[Jacques E. Brandenberger]]\n*[[1909 in science|1909]]  \u2013 [[Bakelite]] hard thermosetting [[plastic]] presented by [[Leo Baekeland]]\n*[[1911 in science|1911]]  \u2013 [[Superconductivity]] discovered by [[Heike Kamerlingh Onnes]]\n*[[1912 in science|1912]]  \u2013 [[Stainless steel]] invented by [[Harry Brearley]]\n*[[1916 in science|1916]]  \u2013 Method for growing single [[crystal]]s of [[metal]]s invented by [[Jan Czochralski]]\n*1919  \u2013 The merchant ship [[Cammell Laird|Fullagar]] has the first all [[Welding|welded]] hull. \n*[[1924 in science|1924]]  \u2013 [[Pyrex]] invented by scientists at [[Corning Glass Works|Corning Incorporated]], a glass with a very low [[coefficient of thermal expansion]]\n*[[1931 in science|1931]]  \u2013 synthetic [[rubber]] called [[neoprene]] developed by [[Julius Nieuwland]] (''see also: [[E.K. Bolton]], [[Wallace Carothers]]'')\n*[[1931 in science|1931]]  \u2013 [[Nylon]] developed by [[Wallace Carothers]]\n*[[1935 in science|1935]]  \u2013 [[Langmuir\u2013Blodgett film]] coating of glass was developed by [[Katharine Burr Blodgett]], creating "invisible glass" which is >99% transmissive\n*[[1938 in science|1938]]  \u2013 The process for making poly-tetrafluoroethylene, better known as [[Polytetrafluoroethylene|Teflon]] discovered by [[Roy J. Plunkett|Roy Plunkett]]\n*[[1939 in science|1939]]  \u2013 Dislocations in metals confirmed by [[Robert W. Cahn]]\n*[[1947 in science|1947]]  \u2013 First [[germanium]] [[point-contact transistor]] invented\n*[[1947 in science|1947]]  \u2013 First commercial application of a [[piezoelectricity|piezoelectric]] [[ceramic]]: [[barium titanate]] used as a [[phonograph]] pickup\n*[[1951 in science|1951]]  \u2013 Individual [[atom]]s seen for the first time using the [[field ion microscope]]\n*[[1953 in science|1953]]  \u2013 Metallic [[catalyst]]s which greatly improve the strength of [[polyethylene]] [[polymer]]s discovered by [[Karl Ziegler]]\n*[[1954 in science|1954]]  \u2013 [[Silicon]] [[solar cell]]s with 6% efficiency made at [[Bell Labs|Bell Laboratories]]\n*[[1954 in science|1954]]  \u2013 [[Argon oxygen decarburization]] (AOD) refining invented by scientists at the [[Union Carbide Corporation]]\n*[[1959 in science|1959]]  \u2013 [[Float glass]] process patented by the [[Pilkington Brothers]]\n*[[1962 in science|1962]]  \u2013 [[SQUID]] superconducting quantum interference device invented\n*[[1966 in science|1966]]  \u2013 [[Stephanie Kwolek]] invented a fibre that would later become known as [[Kevlar]]\n*[[1968 in science|1968]]  \u2013 [[Liquid crystal display]] developed by [[RCA]]\n*[[1970 in science|1970]]  \u2013 Silica [[optical fiber]]s grown by [[Corning Incorporated]]\n*[[1980 in science|1980]]  \u2013 [[Duplex stainless steel]]s developed which resist oxidation in chlorides\n*[[1984 in science|1984]]  \u2013 [[Fold-forming]] system developed by Charles Lewton-Brain to produce complex three dimensional forms rapidly from sheet metal\n*[[1985 in science|1985]]  \u2013 The first [[fullerene]] molecule discovered by scientists at [[Rice University]] (''see also:'' [[Timeline of carbon nanotubes]])\n*[[1986 in science|1986]]  \u2013 The first [[high temperature superconductor]] is discovered by [[Georg Bednorz]] and [[K. Alex M\u00fcller]]\n\n *[[Timeline of scientific discoveries]]\n*[[Timeline of historic inventions]]\n*[[List of inventions named after people]]\n*[[Materials science]]\n*[[Roman metallurgy]]\n\n {{reflist}}\n{{History of physics}}\n{{DEFAULTSORT:Timeline Of Materials Technology}}", "Timeline of materials technology --- Introduction ---|BC": "*28,000 BC \u2013 People wear beads, bracelets, and pendants<ref name=":0">{{Cite book|title=Volume Library 1|publisher=The Southwestern Company|year=2009}}</ref>\n*14,500 BC \u2013 First [[pottery]], made by the [[J\u014dmon period|J\u014dmon]] people of Japan.\n*[[6th millennium BC]] \u2013 [[Copper]] [[metallurgy]] is invented and copper is used for ornamentation (see [[Plo\u010dnik (archaeological site)|Plo\u010dnik]] article)\n*[[2nd millennium BC]] \u2013 [[Bronze]] is used for [[weapon]]s and [[armor]]\n*16th century BC \u2013 The [[Hittites]] develop crude [[History of ferrous metallurgy|iron metallurgy]]\n*13th century BC \u2013 Invention of [[steel]] when [[iron]] and [[charcoal]] are combined properly\n*10th century BC \u2013 [[Glass]] production begins in [[ancient Near East]]\n*[[1st millennium BC]] \u2013 [[Pewter]] beginning to be used in China and [[Egypt]]\n*1000 BC \u2013 The [[Phoenicia|Phoenicians]] introduce dyes made from the purple murex.<ref name=":0" />\n*3rd century BC \u2013 [[Wootz steel]], the first [[crucible steel]], is invented in [[History of India|ancient India]]\n*50s BC \u2013 Glassblowing techniques flourish in [[Phoenicia]]\n*20s BC \u2013 [[Rome|Roman]] [[architecture (built environment)|architect]] [[Vitruvius]] describes low-water-content method for mixing [[concrete]]", "Timeline of materials technology --- Introduction ---|1st millennium": "*3rd century \u2013 [[Cast iron]] widely used in [[Han Dynasty]] China\n*300 \u2013 Greek alchemist Zomius, summarizing the work of Egyptian alchemists, describes arsenic and lead acetate<ref name=":0" />\n*4th century \u2013 [[Iron pillar of Delhi]] is the oldest surviving example of corrosion-resistant steel\n*8th century \u2013 [[Porcelain]] is invented in [[Tang Dynasty]] China\n*8th century \u2013 [[Tin-glazing]] of [[ceramic]]s invented by [[Alchemy and chemistry in Islam|Arabic chemists]] and [[Islamic pottery|potters]] in [[Basra]], [[Iraq]]<ref name=Mason>{{cite journal | last=Mason | first=Robert B. | title=New Looks at Old Pots: Results of Recent Multidisciplinary Studies of Glazed Ceramics from the Islamic World | journal=Muqarnas: Annual on Islamic Art and Architecture | year=1995 | volume=XII | pages=1\u201310 | publisher=Brill Academic Publishers | isbn=90-04-10314-7 | doi=10.2307/1523219| jstor=1523219 }}</ref>{{rp|1}}\n*9th century \u2013 [[Stoneware|Stonepaste ceramics]] invented in [[Iraq]]<ref name=Mason />{{rp|5}}\n*900 \u2013 First systematic classification of chemical substances appears in the works attributed to [[Jabir ibn Hayyan|J\u0101bir ibn \u1e24ayy\u0101n]] (Latin: Geber) and in those of the Persian alchemist and physician [[Abu Bakr al-Razi|Ab\u016b Bakr al-R\u0101z\u012b]] ({{circa}} 865\u2013925, Latin: Rhazes)<ref>{{Cite journal|last1=Karpenko|first1=Vladim\u00edr|last2=Norris|first2=John A.|year=2002|title=Vitriol in the History of Chemistry|journal=Chemick\u00e9 listy|volume=96|issue=12|pages=997\u20131005|url=http://www.chemicke-listy.cz/ojs3/index.php/chemicke-listy/article/view/2266}}</ref>\n*900 \u2013 [[Chemical synthesis|Synthesis]] of [[ammonium chloride]] from [[Organic compound|organic substances]] described in the works attributed to J\u0101bir ibn \u1e24ayy\u0101n (Latin: Geber)<ref>{{Cite book|last=Kraus|first=Paul|author-link=Paul Kraus (Arabist)|year=1942\u20131943|title=J\u00e2bir ibn Hayy\u00e2n: Contribution \u00e0 l'histoire des id\u00e9es scientifiques dans l'Islam. I. Le corpus des \u00e9crits j\u00e2biriens. II. J\u00e2bir et la science grecque|publisher=[[Institut Fran\u00e7ais d'Arch\u00e9ologie Orientale]]|location=Cairo|oclc=468740510|isbn=9783487091150}} Vol. II, pp. 41\u201342.</ref>\n*900 \u2013 Ab\u016b Bakr al-R\u0101z\u012b describes the preparation of plaster of Paris and metallic antimony<ref name=":0" />\n*9th century \u2013 [[Lustreware]] appears in Mesopotamia<ref>{{cite book|title=Ten thousand years of pottery |author=Emmanuel Cooper |publisher=University of Pennsylvania Press |edition=4th |date=2000 |isbn=0-8122-3554-1}}</ref>{{rp|86\u201387}}", "Timeline of materials technology --- Introduction ---|2nd millennium": "*1000 \u2013 Gunpowder is developed in China<ref name=":0" />\n*1340 \u2013 In [[Li\u00e8ge|Li\u00e8ge, Belgium]], the first blast furnaces for the production of iron are developed<ref name=":0" />\n*1448 \u2013 [[Johann Gutenberg]] develops [[type metal]] alloy\n*1450s \u2013 [[Cristallo]], a clear soda-based glass, is invented by [[Angelo Barovier]]\n*[[:Category:1540s in science|1540]] \u2013 [[Vannoccio Biringuccio]] publishes first systematic book on [[metallurgy]]\n*[[:Category:1550s in science|1556]] \u2013 [[Georg Agricola]]'s influential book on [[metallurgy]]\n*[[1590 in science|1590]] \u2013 Glass [[lens (optics)|lens]]es are developed in the Netherlands and used for the first time in [[microscope]]s and [[telescope]]s\n*1664 \u2013 In the pipes supplying water to the gardens at Versailles, cast iron is used<ref name=":0" />\n\n *1717 \u2013 [[Abraham Darby I|Abraham Darby]] makes iron with coke, a derivative of coal<ref name=":0" />\n*[[1738 in science|1738]] \u2013 Metallic [[zinc]] processed by [[distillation]] from [[calamine (mineral)|calamine]] and charcoal patented by [[William Champion (metallurgist)|William Champion]]\n*[[1740 in science|1740]]  \u2013 [[Crucible steel]] technique developed by [[Benjamin Huntsman]]\n*1774 \u2013 \n**Joseph Priestley discovers oxygen<ref name=":0" />\n**Johann Gottlieb Gahn discovers manganese<ref name=":0" />\n**Karl Wilhelm Scheele discovers chlorine<ref name=":0" />\n*[[1779 in science|1779]]  \u2013 Hydraulic cement ([[stucco]]) patented by [[Bryan Higgins]] for use as an exterior [[plaster]]\n*[[1799 in science|1799]]  \u2013 [[Acid]] [[battery (electricity)|battery]] made from copper/zinc by [[Alessandro Volta]]\n\n *[[1821 in science|1821]]  \u2013 [[Thermocouple]] invented by [[Thomas Johann Seebeck]]\n*[[1824 in science|1824]]  \u2013 [[Portland cement]] patent issued to [[Joseph Aspdin]]\n*[[1825 in science|1825]]  \u2013 Metallic [[aluminum]] produced by [[Hans Christian \u00d8rsted]]\n*[[1839 in science|1839]]  \u2013 [[Vulcanization|Vulcanized rubber]] invented by [[Charles Goodyear]]\n*[[1839 in science|1839]]  \u2013 [[Silver]]-based [[photography|photographic]] processes invented by [[Louis Daguerre]] and [[William Fox Talbot]]\n*[[1855 in science|1855]]  \u2013 [[Bessemer process]] for mass production of steel patented by [[Henry Bessemer]]\n*[[1861 in science|1861]]  \u2013 Color photography demonstrated by [[James Clerk Maxwell]]\n*[[1883 in science|1883]]  \u2013 First [[solar cell]]s using [[selenium]] waffles made by [[Charles Fritts]]\n*1893  \u2013 [[Exothermic welding|Thermite Welding]] developed and soon used to weld rails\n\n *[[1902 in science|1902]]  \u2013 [[Chemical synthesis|Synthetic]] [[ruby|rubies]] created by the [[Verneuil process]] developed by [[Auguste Verneuil]]\n*[[1908 in science|1908]]  \u2013 [[Cellophane]] invented by [[Jacques E. Brandenberger]]\n*[[1909 in science|1909]]  \u2013 [[Bakelite]] hard thermosetting [[plastic]] presented by [[Leo Baekeland]]\n*[[1911 in science|1911]]  \u2013 [[Superconductivity]] discovered by [[Heike Kamerlingh Onnes]]\n*[[1912 in science|1912]]  \u2013 [[Stainless steel]] invented by [[Harry Brearley]]\n*[[1916 in science|1916]]  \u2013 Method for growing single [[crystal]]s of [[metal]]s invented by [[Jan Czochralski]]\n*1919  \u2013 The merchant ship [[Cammell Laird|Fullagar]] has the first all [[Welding|welded]] hull. \n*[[1924 in science|1924]]  \u2013 [[Pyrex]] invented by scientists at [[Corning Glass Works|Corning Incorporated]], a glass with a very low [[coefficient of thermal expansion]]\n*[[1931 in science|1931]]  \u2013 synthetic [[rubber]] called [[neoprene]] developed by [[Julius Nieuwland]] (''see also: [[E.K. Bolton]], [[Wallace Carothers]]'')\n*[[1931 in science|1931]]  \u2013 [[Nylon]] developed by [[Wallace Carothers]]\n*[[1935 in science|1935]]  \u2013 [[Langmuir\u2013Blodgett film]] coating of glass was developed by [[Katharine Burr Blodgett]], creating "invisible glass" which is >99% transmissive\n*[[1938 in science|1938]]  \u2013 The process for making poly-tetrafluoroethylene, better known as [[Polytetrafluoroethylene|Teflon]] discovered by [[Roy J. Plunkett|Roy Plunkett]]\n*[[1939 in science|1939]]  \u2013 Dislocations in metals confirmed by [[Robert W. Cahn]]\n*[[1947 in science|1947]]  \u2013 First [[germanium]] [[point-contact transistor]] invented\n*[[1947 in science|1947]]  \u2013 First commercial application of a [[piezoelectricity|piezoelectric]] [[ceramic]]: [[barium titanate]] used as a [[phonograph]] pickup\n*[[1951 in science|1951]]  \u2013 Individual [[atom]]s seen for the first time using the [[field ion microscope]]\n*[[1953 in science|1953]]  \u2013 Metallic [[catalyst]]s which greatly improve the strength of [[polyethylene]] [[polymer]]s discovered by [[Karl Ziegler]]\n*[[1954 in science|1954]]  \u2013 [[Silicon]] [[solar cell]]s with 6% efficiency made at [[Bell Labs|Bell Laboratories]]\n*[[1954 in science|1954]]  \u2013 [[Argon oxygen decarburization]] (AOD) refining invented by scientists at the [[Union Carbide Corporation]]\n*[[1959 in science|1959]]  \u2013 [[Float glass]] process patented by the [[Pilkington Brothers]]\n*[[1962 in science|1962]]  \u2013 [[SQUID]] superconducting quantum interference device invented\n*[[1966 in science|1966]]  \u2013 [[Stephanie Kwolek]] invented a fibre that would later become known as [[Kevlar]]\n*[[1968 in science|1968]]  \u2013 [[Liquid crystal display]] developed by [[RCA]]\n*[[1970 in science|1970]]  \u2013 Silica [[optical fiber]]s grown by [[Corning Incorporated]]\n*[[1980 in science|1980]]  \u2013 [[Duplex stainless steel]]s developed which resist oxidation in chlorides\n*[[1984 in science|1984]]  \u2013 [[Fold-forming]] system developed by Charles Lewton-Brain to produce complex three dimensional forms rapidly from sheet metal\n*[[1985 in science|1985]]  \u2013 The first [[fullerene]] molecule discovered by scientists at [[Rice University]] (''see also:'' [[Timeline of carbon nanotubes]])\n*[[1986 in science|1986]]  \u2013 The first [[high temperature superconductor]] is discovered by [[Georg Bednorz]] and [[K. Alex M\u00fcller]]"}},
{"article_title": "Timeline of lighting technology", "pageid": "58744", "revid": "1029026371", "timestamp": "2021-06-17T12:55:57Z", "history_paths": [["Timeline of lighting technology --- Introduction ---"], ["Timeline of lighting technology --- Introduction ---", "Antiquity"], ["Timeline of lighting technology --- Introduction ---", "18th century"], ["Timeline of lighting technology --- Introduction ---", "19th century"], ["Timeline of lighting technology --- Introduction ---", "20th century"], ["Timeline of lighting technology --- Introduction ---", "21st century"]], "categories": ["lighting", "technology timelines", "types of lamp"], "heading_tree": {"Timeline of lighting technology --- Introduction ---": {"Antiquity": {}, "18th century": {}, "19th century": {}, "20th century": {}, "21st century": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Timeline of lighting technology --- Introduction ---": "[[File:Eclairage.jpg|thumb|Lighting through the ages ([[:File:Eclairage.jpg|legend]])]]\n{{Timeline of lighting technology}}\nArtificial [[lighting]] technology began to be developed tens of thousands of years ago and continues to be refined in the present day.\n\n * 125,000 BC Widespread [[control of fire by early humans]].<ref name="beyondveg">{{cite web|url=http://www.beyondveg.com/nicholson-w/hb/hb-interview2c.shtml|title=First Control of Fire by Human Beings\u2014How Early?|access-date=2007-11-12}}</ref>\n* 70,000 BC A hollow rock, shell, or other natural found object was filled with moss or a similar material that was soaked in animal fat and ignited.<ref>{{cite book\n|page=270\n|title=Domestic Technology: A Chronology of Developments\n|last=DuVall\n|first=Nell\n|publisher=G.K. Hall\n|year=1988}}</ref>\n* c. 4500 BC [[oil lamp]]s\n* c. 3000 BC [[candle]]s are invented.\n\n * 1780  [[Aim\u00e9 Argand]] invents the [[Argand lamp|central draught fixed oil lamp]].\n* 1784  Argand adds glass chimney to central draught lamp.\n* 1792  [[William Murdoch]] begins experimenting with [[gas lighting]] and probably produced the first gas light in this year.\n* 1800  French watchmaker [[Bernard Guillaume Carcel]] overcomes the disadvantages of the Argand-type lamps with his clockwork fed [[Carcel lamp]].\n\n * 1800-1809 [[Humphry Davy]] invents the [[arc lamp]] when using Voltaic piles (battery) for his electrolysis experiments.\n* 1802  William Murdoch illuminates the exterior of the [[Soho Foundry]] with gas.\n* 1805  Philips and Lee's Cotton Mill, [[Manchester]] was the first industrial factory to be fully lit by gas.\n* 1809  Humphry Davy publicly demonstrates first electric lamp over 10,000 lumens, at the Royal Society.<ref name="DrThomasKlett">Dr. Thomas Klett, Geschichte der Lichttechnik/History of Lighting</ref>\n* 1813  National Heat and Light Company formed by [[Fredrich Winzer]] (Winsor)\n* 1815  Humphry Davy invents the [[Davy lamp|miner's safety lamp]].\n* 1823 [[Johann Wolfgang D\u00f6bereiner]] invents the [[D\u00f6bereiner's lamp]].\n* 1835  [[James Bowman Lindsay]] demonstrates a [[light bulb]] based electric lighting system to the citizens of [[Dundee, Scotland|Dundee]].\n* 1841  Arc-lighting is used as experimental public lighting in Paris.\n* 1853  [[Ignacy Lukasiewicz]] invents the modern [[kerosene lamp]].\n* 1856  [[glassblowing|glassblower]] [[Heinrich Geissler]] confines the electric arc in a [[Geissler tube]].\n* 1867  [[A. E. Becquerel]] demonstrates the first [[fluorescent lamp]].<ref>http://txchnologist.com/post/77710091911/in-the-beginning-10-inventors-of-the-incandescent In The Beginning: 10 Inventors of the Incandescent Lightbulb</ref>\n* 1879 (About Christmas time) Col. R.E. Crompton illuminated his home in Porchester Gardens, using a primary battery of Grove Cells, then a generator which was better. He gave special parties and illuminated his drawing room and dining room. Source: Practical Electrical Engineering, Newnes. Article entitled "The Development of Electric Lighting". \n* 1874  [[Alexander Lodygin]] patents an [[incandescent light bulb]].\n* 1875   [[Henry Woodward (inventor)|Henry Woodward]] patents an electric light bulb.\n* 1876   [[Pavel Yablochkov]] invents the [[Yablochkov candle]], the first practical carbon arc lamp, for public street lighting in Paris.\n* 1879   [[Thomas Edison]] and [[Joseph Wilson Swan]] patent the carbon-thread [[incandescent lamp]]. It lasted 40 hours.\n* 1880 Edison produced a 16-watt lightbulb that lasts 1500 hours.\n* 1882 Introduction of large scale [[direct current]] based indoor incandescent lighting and lighting [[utility]] with Edison's first [[Pearl Street Station]]\n* c. 1885 Incandescent [[gas mantle]] invented, revolutionises [[gas lighting]].\n* 1886   [[Great Barrington, Massachusetts]] demonstration project, a much more versatile (long-distance transmission) [[transformer]] based [[alternating current]] based indoor incandescent lighting system introduced by [[William Stanley, Jr.]] working for [[George Westinghouse]].<ref>Great Barrington Historical Society, Great Barrington, Massachusetts</ref>  Stanley lit 23 businesses along a 4000 feet length of main street stepping a 500 AC volt current at the street down to 100 volts to power incandescent lamps at each location.<ref>[http://www.edisontechcenter.org/GreatBarrington.html Great Barrington 1886 - Inspiring an industry toward AC power]</ref>\n* 1893 GE introduces first commercial fully enclosed carbon arc lamp. Sealed in glass globes, it lasts 100h and therefore 10 times longer than hitherto carbon arc lamps <ref name="DrThomasKlett"/><ref name=Gorowitz>Bernard Gorowitz Ed., The General Electric Story</ref>\n* 1893 [[Nikola Tesla]] puts forward his ideas on high frequency and wireless electric lighting<ref>W. Bernard Carlson, Tesla: Inventor of the Electrical Age, page 132</ref><ref>note: at [[St. Louis, Missouri]], Tesla public demonstration called, "[[s:On Light and Other High-Frequency Phenomena|On Light and Other High-Frequency Phenomena]]", (Journal of the Franklin Institute, Volume 136 By Persifor Frazer, Franklin Institute, Philadelphia, Pa)</ref> which included public demonstrations where he lit a [[Geissler tube]] wirelessly.\n* 1894 [[D. McFarlan Moore]] creates the [[Moore tube]], precursor of [[glow discharge|electric gas-discharge]] lamps.\n* 1897 [[Walther Nernst]] invents and patents his [[Nernst lamp|incandescent lamp]], based on [[Solid state (electronics)|solid state]] [[electrolyte]]s.\n\n * 1901   [[Peter Cooper Hewitt]] creates the first commercial [[mercury-vapor lamp]].\n* 1904   [[Alexander Just]] and [[Franjo Hanaman]] invent the [[tungsten]] filament for incandescent lightbulbs.\n* 1910   [[Georges Claude]] demonstrates [[neon lighting]] at the [[Paris Motor Show]].\n* 1912   Charles P. Steinmetz invents the [[metal-halide lamp]].<ref>{{cite web|title=A brief history of high intensity discharge hid lighting|url=https://www.shineretrofits.com/knowledge-base/lighting-learning-center/a-brief-history-of-high-intensity-discharge-hid-lighting.html|website=Shine Retrofits|access-date=21 December 2017}}</ref>\n* 1913   [[Irving Langmuir]] discovers that [[inert gas]] could double the luminous efficacy of incandescent lightbulbs.\n* 1917   Burnie Lee Benbow patents the [[coiled coil]] filament.\n* 1920   [[Arthur H. Compton]] invents the [[sodium-vapor lamp]].<ref>{{cite web|title=Sodium Lamp|url=http://www.edisontechcenter.org/SodiumLamps.html|website=Edison Center|access-date=21 December 2017|url-status=dead|archive-url=https://web.archive.org/web/20140920234320/http://www.edisontechcenter.org/SodiumLamps.html|archive-date=20 September 2014}}</ref>\n* 1921   Junichi Miura creates the first incandescent lightbulb to utilize a coiled coil filament.\n* 1925   [[Marvin Pipkin]] invents the first internal frosted lightbulb.\n* 1926   [[Edmund Germer]] patents the modern fluorescent lamp.\n* 1927   [[Oleg Losev]] creates the first [[light-emitting diode|LED]] (light-emitting diode).\n* 1953   Elmer Fridrich invents the [[halogen light bulb]].<ref>{{cite web|title=20th Century Inventors: Tungsten Halogen Lamp|url=http://americanhistory.si.edu/lighting/bios/frid.htm|website=American History|access-date=21 December 2017}}</ref>\n* 1953   Andr\u00e9 Bernanose and several colleagues observe [[electroluminescence]] in organic materials.<ref>{{cite journal|author= Bernanose, A.|author2= Comte, M.|author3 = Vouaux, P. |journal= J. Chim. Phys.|year = 1953|volume= 50|page= 64|title= A new method of light emission by certain organic compounds|doi= 10.1051/jcp/1953500064}}</ref><ref>{{cite journal|author= Bernanose, A. |author2 = Vouaux, P.|journal= J. Chim. Phys.|year= 1953|volume= 50|page= 261|title= Organic electroluminescence type of emission|doi = 10.1051/jcp/1953500261}}</ref>\n* 1960   [[Theodore H. Maiman]] creates the first [[laser]].\n* 1962   [[Nick Holonyak]] Jr. develops the first practical visible-spectrum (red) light-emitting diode.\n* 1963   Kurt Schmidt invents the first [[Sodium-vapor lamp#High-pressure sodium|high pressure sodium-vapor lamp]].<ref>{{cite web|last1=Schmidt|first1=Kurt|title=High pressure sodium vapor lamp|url=https://www.google.com/patents/US3248590|website=Google Patents|access-date=21 December 2017}}</ref>\n* 1972   [[M. George Craford]] invents the first yellow light-emitting diode.\n* 1972   Herbert Paul Maruska and Jacques Pankove create the first violet light-emitting diode.\n* 1981   Philips sells their first Compact Fluorescent Energy Saving Lamps, with integrated conventional ballast.\n* 1981   Thorn Lighting Group exhibits the [[ceramic discharge metal-halide lamp]].\n* 1985   Osram answers with the first electronic Energy Saving Lamps to be very successful <ref name="DrThomasKlett" />\n* 1987   [[Ching W. Tang]] and [[Steven Van Slyke]] at [[Eastman Kodak]] create the first practical [[OLED|organic light-emitting diode]] (OLED).\n* 1990   Michael Ury, Charles Wood, and several colleagues develop the [[sulfur lamp]].\n* 1991   [[Philips]] invents a fluorescent lightbulb that lasts 60,000 hours using [[Electromagnetic induction|magnetic induction]].\n* 1994   T5 lamps with cool tip are introduced to become the leading fluorescent lamps with up to 117 lm/W with good color rendering. These and almost all new fluorescent lamps are to be operated on electronic ballasts only.<ref name="DrThomasKlett" />\n* 1994   The first commercial [[sulfur lamp]] is sold by Fusion Lighting.\n* 1995   [[Shuji Nakamura]] at [[Nichia|Nichia labs]] invents the first practical blue and with additional phosphor, white LED, starting an LED boom.<ref name="DrThomasKlett" />\n\n * 2008   Ushio Lighting demonstrates the first [[LED Filament]].\n* 2011   [[Philips]] wins [[L Prize]] for LED screw-in lamp equivalent to 60W incandescent A-lamp for general use.\n\n {{reflist}}\n\n{{Clear}}\n{{Refimprove|date=June 2008}}", "Timeline of lighting technology --- Introduction ---|Antiquity": "* 125,000 BC Widespread [[control of fire by early humans]].<ref name="beyondveg">{{cite web|url=http://www.beyondveg.com/nicholson-w/hb/hb-interview2c.shtml|title=First Control of Fire by Human Beings\u2014How Early?|access-date=2007-11-12}}</ref>\n* 70,000 BC A hollow rock, shell, or other natural found object was filled with moss or a similar material that was soaked in animal fat and ignited.<ref>{{cite book\n|page=270\n|title=Domestic Technology: A Chronology of Developments\n|last=DuVall\n|first=Nell\n|publisher=G.K. Hall\n|year=1988}}</ref>\n* c. 4500 BC [[oil lamp]]s\n* c. 3000 BC [[candle]]s are invented.", "Timeline of lighting technology --- Introduction ---|18th century": "* 1780  [[Aim\u00e9 Argand]] invents the [[Argand lamp|central draught fixed oil lamp]].\n* 1784  Argand adds glass chimney to central draught lamp.\n* 1792  [[William Murdoch]] begins experimenting with [[gas lighting]] and probably produced the first gas light in this year.\n* 1800  French watchmaker [[Bernard Guillaume Carcel]] overcomes the disadvantages of the Argand-type lamps with his clockwork fed [[Carcel lamp]].", "Timeline of lighting technology --- Introduction ---|19th century": "* 1800-1809 [[Humphry Davy]] invents the [[arc lamp]] when using Voltaic piles (battery) for his electrolysis experiments.\n* 1802  William Murdoch illuminates the exterior of the [[Soho Foundry]] with gas.\n* 1805  Philips and Lee's Cotton Mill, [[Manchester]] was the first industrial factory to be fully lit by gas.\n* 1809  Humphry Davy publicly demonstrates first electric lamp over 10,000 lumens, at the Royal Society.<ref name="DrThomasKlett">Dr. Thomas Klett, Geschichte der Lichttechnik/History of Lighting</ref>\n* 1813  National Heat and Light Company formed by [[Fredrich Winzer]] (Winsor)\n* 1815  Humphry Davy invents the [[Davy lamp|miner's safety lamp]].\n* 1823 [[Johann Wolfgang D\u00f6bereiner]] invents the [[D\u00f6bereiner's lamp]].\n* 1835  [[James Bowman Lindsay]] demonstrates a [[light bulb]] based electric lighting system to the citizens of [[Dundee, Scotland|Dundee]].\n* 1841  Arc-lighting is used as experimental public lighting in Paris.\n* 1853  [[Ignacy Lukasiewicz]] invents the modern [[kerosene lamp]].\n* 1856  [[glassblowing|glassblower]] [[Heinrich Geissler]] confines the electric arc in a [[Geissler tube]].\n* 1867  [[A. E. Becquerel]] demonstrates the first [[fluorescent lamp]].<ref>http://txchnologist.com/post/77710091911/in-the-beginning-10-inventors-of-the-incandescent In The Beginning: 10 Inventors of the Incandescent Lightbulb</ref>\n* 1879 (About Christmas time) Col. R.E. Crompton illuminated his home in Porchester Gardens, using a primary battery of Grove Cells, then a generator which was better. He gave special parties and illuminated his drawing room and dining room. Source: Practical Electrical Engineering, Newnes. Article entitled "The Development of Electric Lighting". \n* 1874  [[Alexander Lodygin]] patents an [[incandescent light bulb]].\n* 1875   [[Henry Woodward (inventor)|Henry Woodward]] patents an electric light bulb.\n* 1876   [[Pavel Yablochkov]] invents the [[Yablochkov candle]], the first practical carbon arc lamp, for public street lighting in Paris.\n* 1879   [[Thomas Edison]] and [[Joseph Wilson Swan]] patent the carbon-thread [[incandescent lamp]]. It lasted 40 hours.\n* 1880 Edison produced a 16-watt lightbulb that lasts 1500 hours.\n* 1882 Introduction of large scale [[direct current]] based indoor incandescent lighting and lighting [[utility]] with Edison's first [[Pearl Street Station]]\n* c. 1885 Incandescent [[gas mantle]] invented, revolutionises [[gas lighting]].\n* 1886   [[Great Barrington, Massachusetts]] demonstration project, a much more versatile (long-distance transmission) [[transformer]] based [[alternating current]] based indoor incandescent lighting system introduced by [[William Stanley, Jr.]] working for [[George Westinghouse]].<ref>Great Barrington Historical Society, Great Barrington, Massachusetts</ref>  Stanley lit 23 businesses along a 4000 feet length of main street stepping a 500 AC volt current at the street down to 100 volts to power incandescent lamps at each location.<ref>[http://www.edisontechcenter.org/GreatBarrington.html Great Barrington 1886 - Inspiring an industry toward AC power]</ref>\n* 1893 GE introduces first commercial fully enclosed carbon arc lamp. Sealed in glass globes, it lasts 100h and therefore 10 times longer than hitherto carbon arc lamps <ref name="DrThomasKlett"/><ref name=Gorowitz>Bernard Gorowitz Ed., The General Electric Story</ref>\n* 1893 [[Nikola Tesla]] puts forward his ideas on high frequency and wireless electric lighting<ref>W. Bernard Carlson, Tesla: Inventor of the Electrical Age, page 132</ref><ref>note: at [[St. Louis, Missouri]], Tesla public demonstration called, "[[s:On Light and Other High-Frequency Phenomena|On Light and Other High-Frequency Phenomena]]", (Journal of the Franklin Institute, Volume 136 By Persifor Frazer, Franklin Institute, Philadelphia, Pa)</ref> which included public demonstrations where he lit a [[Geissler tube]] wirelessly.\n* 1894 [[D. McFarlan Moore]] creates the [[Moore tube]], precursor of [[glow discharge|electric gas-discharge]] lamps.\n* 1897 [[Walther Nernst]] invents and patents his [[Nernst lamp|incandescent lamp]], based on [[Solid state (electronics)|solid state]] [[electrolyte]]s.", "Timeline of lighting technology --- Introduction ---|20th century": "* 1901   [[Peter Cooper Hewitt]] creates the first commercial [[mercury-vapor lamp]].\n* 1904   [[Alexander Just]] and [[Franjo Hanaman]] invent the [[tungsten]] filament for incandescent lightbulbs.\n* 1910   [[Georges Claude]] demonstrates [[neon lighting]] at the [[Paris Motor Show]].\n* 1912   Charles P. Steinmetz invents the [[metal-halide lamp]].<ref>{{cite web|title=A brief history of high intensity discharge hid lighting|url=https://www.shineretrofits.com/knowledge-base/lighting-learning-center/a-brief-history-of-high-intensity-discharge-hid-lighting.html|website=Shine Retrofits|access-date=21 December 2017}}</ref>\n* 1913   [[Irving Langmuir]] discovers that [[inert gas]] could double the luminous efficacy of incandescent lightbulbs.\n* 1917   Burnie Lee Benbow patents the [[coiled coil]] filament.\n* 1920   [[Arthur H. Compton]] invents the [[sodium-vapor lamp]].<ref>{{cite web|title=Sodium Lamp|url=http://www.edisontechcenter.org/SodiumLamps.html|website=Edison Center|access-date=21 December 2017|url-status=dead|archive-url=https://web.archive.org/web/20140920234320/http://www.edisontechcenter.org/SodiumLamps.html|archive-date=20 September 2014}}</ref>\n* 1921   Junichi Miura creates the first incandescent lightbulb to utilize a coiled coil filament.\n* 1925   [[Marvin Pipkin]] invents the first internal frosted lightbulb.\n* 1926   [[Edmund Germer]] patents the modern fluorescent lamp.\n* 1927   [[Oleg Losev]] creates the first [[light-emitting diode|LED]] (light-emitting diode).\n* 1953   Elmer Fridrich invents the [[halogen light bulb]].<ref>{{cite web|title=20th Century Inventors: Tungsten Halogen Lamp|url=http://americanhistory.si.edu/lighting/bios/frid.htm|website=American History|access-date=21 December 2017}}</ref>\n* 1953   Andr\u00e9 Bernanose and several colleagues observe [[electroluminescence]] in organic materials.<ref>{{cite journal|author= Bernanose, A.|author2= Comte, M.|author3 = Vouaux, P. |journal= J. Chim. Phys.|year = 1953|volume= 50|page= 64|title= A new method of light emission by certain organic compounds|doi= 10.1051/jcp/1953500064}}</ref><ref>{{cite journal|author= Bernanose, A. |author2 = Vouaux, P.|journal= J. Chim. Phys.|year= 1953|volume= 50|page= 261|title= Organic electroluminescence type of emission|doi = 10.1051/jcp/1953500261}}</ref>\n* 1960   [[Theodore H. Maiman]] creates the first [[laser]].\n* 1962   [[Nick Holonyak]] Jr. develops the first practical visible-spectrum (red) light-emitting diode.\n* 1963   Kurt Schmidt invents the first [[Sodium-vapor lamp#High-pressure sodium|high pressure sodium-vapor lamp]].<ref>{{cite web|last1=Schmidt|first1=Kurt|title=High pressure sodium vapor lamp|url=https://www.google.com/patents/US3248590|website=Google Patents|access-date=21 December 2017}}</ref>\n* 1972   [[M. George Craford]] invents the first yellow light-emitting diode.\n* 1972   Herbert Paul Maruska and Jacques Pankove create the first violet light-emitting diode.\n* 1981   Philips sells their first Compact Fluorescent Energy Saving Lamps, with integrated conventional ballast.\n* 1981   Thorn Lighting Group exhibits the [[ceramic discharge metal-halide lamp]].\n* 1985   Osram answers with the first electronic Energy Saving Lamps to be very successful <ref name="DrThomasKlett" />\n* 1987   [[Ching W. Tang]] and [[Steven Van Slyke]] at [[Eastman Kodak]] create the first practical [[OLED|organic light-emitting diode]] (OLED).\n* 1990   Michael Ury, Charles Wood, and several colleagues develop the [[sulfur lamp]].\n* 1991   [[Philips]] invents a fluorescent lightbulb that lasts 60,000 hours using [[Electromagnetic induction|magnetic induction]].\n* 1994   T5 lamps with cool tip are introduced to become the leading fluorescent lamps with up to 117 lm/W with good color rendering. These and almost all new fluorescent lamps are to be operated on electronic ballasts only.<ref name="DrThomasKlett" />\n* 1994   The first commercial [[sulfur lamp]] is sold by Fusion Lighting.\n* 1995   [[Shuji Nakamura]] at [[Nichia|Nichia labs]] invents the first practical blue and with additional phosphor, white LED, starting an LED boom.<ref name="DrThomasKlett" />", "Timeline of lighting technology --- Introduction ---|21st century": "* 2008   Ushio Lighting demonstrates the first [[LED Filament]].\n* 2011   [[Philips]] wins [[L Prize]] for LED screw-in lamp equivalent to 60W incandescent A-lamp for general use."}},
{"article_title": "Unmanned aerial vehicle", "pageid": "58900", "revid": "1062928707", "timestamp": "2021-12-31T06:29:20Z", "history_paths": [["Unmanned aerial vehicle --- Introduction ---", "History"]], "categories": ["unmanned aerial vehicles", "wireless", "avionics", "embedded systems", "robotics", "emerging technologies", "articles containing video clips"], "heading_tree": {"Unmanned aerial vehicle --- Introduction ---": {"Terminology": {}, "Classifications": {"Based on the weight": {}, "Based on the degree of autonomy": {}, "Based on the altitude": {}, "Based on the composite criteria": {}}, "History": {"Early drones": {}, "World War II": {}, "Postwar period": {}, "Modern UAVs": {}}, "Design": {"Aircraft configuration": {}, "Propulsion": {}, "Ornithopters - wing propulsion": {}}, "Computer control systems": {"Architecture": {"Sensors": {}, "Actuators": {}, "Software": {}, "Loop principles": {}, "Communications": {}}, "Autonomy": {}}, "Performance considerations": {"Flight envelope": {}, "Endurance": {}, "Reliability": {}}, "Applications": {"Warfare": {}, "Civil": {"Aerial photography": {}, "Agriculture and forestry": {}, "Law enforcement": {}}}, "Safety and security": {"Threats": {"Nuisance": {}, "Security vulnerabilities": {}, "Aggression": {}}, "Countermeasures": {"Counter unmanned air system": {}, "Regulation": {}, "Export controls": {}}}, "See also": {}, "References": {"Citations": {}, "Bibliography": {}}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Unmanned aerial vehicle --- Introduction ---|History": "{{Main|History of unmanned aerial vehicles}}\n[[File:Winston Churchill and the Secretary of State for War waiting to see the launch of a de Havilland Queen Bee radio-controlled target drone, 6 June 1941. H10307.jpg|thumb|right|[[Winston Churchill]] and others waiting to watch the launch of a [[De Havilland Tiger Moth#Gunnery target drone|de Havilland Queen Bee]] [[target drone]], 6 June 1941]]\n[[File:Teledyne-Ryan-Firebee-hatzerim-1.jpg|thumb|right|A [[Ryan Firebee]], one of a series of target drones/unpiloted aerial vehicles that first flew in 1951. [[Israeli Air Force Museum]], Hatzerim airbase, Israel, 2006]]\n[[File:Last preparation before first tactical mission across Suez canal (1969).jpg|thumb|Last preparations before the first tactical UAV mission across the Suez canal (1969). Standing: Major Shabtai Brill from the Israeli intelligence corps, the innovator of the tactical UAV.]]\n[[File:Tadiran-Mastiff-III-hatzerim-1.jpg|thumb|The Israeli [[Tadiran Mastiff]], which first flew in 1975, is seen by many{{quantify|date=December 2021}} as the first modern battlefield UAV, due to its data-link system, endurance-loitering, and live video-streaming.<ref>The ''Encyclopedia of the Arab-Israeli Conflict: A Political, Social, and Military History: A Political, Social, and Military History'', ABC-CLIO, 12 May 2008, by Spencer C. Tucker, Priscilla Mary Roberts, pages 1054\u201355 ISBN</ref>]]\n\n The earliest recorded use of an unmanned aerial vehicle for warfighting occurred in July 1849,<ref>[https://books.google.com/books?id=YSSPAgAAQBAJ&pg=PT43 The Future of Drone Use: Opportunities and Threats from Ethical and Legal Perspectives], Asser Press{{snd}} Springer, chapter by Alan McKenna, page 355</ref> with a [[balloon carrier]] (the precursor to the [[aircraft carrier]])<ref name="Kaplan">{{cite book|last=Kaplan|first=Philip|title=Naval Aviation in the Second World War|url= https://books.google.com/books?id=pDARBQAAQBAJ&pg=PT19|year= 2013|publisher=Pen and Sword|isbn= 978-1-4738-2997-8|page=19}}</ref> in the first offensive use of [[air power]] in [[naval aviation]].<ref name="Hallion">{{cite book|last= Hallion|first= Richard P.|title= Taking Flight: Inventing the Aerial Age, from Antiquity through the First World War|url= https://archive.org/details/takingflightinve0000hall|url-access= registration|year= 2003|publisher= Oxford University Press|isbn=978-0-19-028959-1|page=[https://archive.org/details/takingflightinve0000hall/page/66 66]}}</ref><ref name="LaymanFirst">[https://archive.org/details/navalaviationinf00laym <!-- quote=vulcano balloon venice. --> Naval Aviation in the First World War: Its Impact and Influence], R. D. Layman, page 56</ref><ref name="RennerFirst">{{cite book|last=Renner|first=Stephen L.|title=Broken Wings: The Hungarian Air Force, 1918\u201345|url=https://books.google.com/books?id=HDoJDgAAQBAJ&pg=PP1|year=2016|publisher=Indiana University Press|isbn=978-0-253-02339-1|page=2}}</ref> Austrian forces besieging Venice attempted to launch some 200 [[incendiary balloon]]s at the besieged city. The balloons were launched mainly from land; however, some were also launched from the Austrian ship {{SMS|Vulcano}}. At least one bomb fell in the city; however, due to the wind changing after launch, most of the balloons missed their target, and some drifted back over Austrian lines and the launching ship ''Vulcano''.<ref name="Murphy">{{cite book|last= Murphy|first=Justin D.|title=Military Aircraft, Origins to 1918: An Illustrated History of Their Impact|url= https://books.google.com/books?id=7pS1QpH8FRgC&pg=PA9|year= 2005|publisher=ABC-CLIO|isbn= 978-1-85109-488-2|pages=9\u201310}}</ref><ref name="Haydon">{{cite book|last=Haydon|first=F. Stansbury|title= Military Ballooning During the Early Civil War|url= https://archive.org/details/militaryballooni00hayd |url-access= registration|year=2000|publisher=JHU Press|isbn=978-0-8018-6442-1|pages=[https://archive.org/details/militaryballooni00hayd/page/18 18]\u201320}}</ref><ref name="Mikesh">{{Cite web |url=https://repository.si.edu/bitstream/handle/10088/18679/SAoF-0009-Lo_res.pdf|title=Mikesh, Robert C. "Japan's World War II balloon bomb attacks on North America." (1973).}}</ref>\n\nThe Spanish engineer [[Leonardo Torres y Quevedo]] introduced a radio-based control-system called the "''Telekino''" at the [[Paris Academy of Science]] in 1903 with the intention of testing an [[Astra-Torres airship| airship]] of his own design without risking human lives.<ref>Sarkar 2006, page 97</ref><ref>H. R. Everett, Unmanned Systems of World Wars I and II, MIT Press - 2015, pages 91-95</ref>\n\nSignificant development of drones started in the 1900s, and originally focused on providing practice targets for training military personnel. The earliest attempt at a powered UAV was [[Archibald Low| A. M. Low]]'s "Aerial Target" in 1916.<ref name="autogenerated1">Taylor, John W. R.. ''Jane's Pocket Book of Remotely Piloted Vehicles''.</ref> Low confirmed that Geoffrey de Havilland's monoplane was the one that flew under control on 21 March 1917 using his radio system.<ref>Professor A. M. Low  FLIGHT, 3 October 1952  page 436 \u201cThe First Guided Missile\u201d</ref> Following this successful demonstration in the spring of 1917 Low was transferred to develop aircraft controlled fast motor launches [[Coastal Motor Boat|D.C.B.s]] with the Royal Navy in 1918 intended to attack shipping and port installations and he also assisted [[Frank Arthur Brock|Wing Commander Brock]] in preparations for the [[Zeebrugge Raid|Zeebrugge Raid]]. Other [[British unmanned aerial vehicles of World War I| British unmanned developments]] followed, leading to the fleet of over 400 [[de Havilland Tiger Moth |de Havilland 82 Queen Bee]] aerial targets that went into service in 1935.\n\n[[Nikola Tesla]] described a fleet of uncrewed aerial combat vehicles in 1915.<ref name="armyeyes">{{cite web |last=Dempsey |first=Martin E.|url= http://www.rucker.army.mil/usaace/uas/US%20Army%20UAS%20RoadMap%202010%202035.pdf |title=Eyes of the Army\u2014U.S. Army Roadmap for Unmanned Aircraft Systems 2010\u20132035 |publisher=[[U.S. Army]] |date=9 April 2010 |access-date=6 March 2011 |archive-date=22 September 2018 |archive-url= https://web.archive.org/web/20180922052536/http://www.rucker.army.mil/usaace/uas/US%20Army%20UAS%20RoadMap%202010%202035.pdf |url-status=dead }}</ref> These developments also inspired the construction of the [[Kettering Bug]] by [[Charles Kettering]] from [[Dayton, Ohio]] and the [[Hewitt-Sperry Automatic Airplane]] - initially meant as an uncrewed plane that would carry an explosive payload to a predetermined target. Development continued during World War I, when the [[Dayton-Wright Airplane Company]] invented a pilotless [[aerial torpedo]] that would explode at a preset time.<ref>{{cite web |last= Says|first= Robert Kanyike|title= History of U.S. Drones|url= http://understandingempire.wordpress.com/2-0-a-brief-history-of-u-s-drones/|date= 21 May 2012}}</ref> \n\nThe film star and [[model-airplane]] enthusiast [[Reginald Denny (actor)| Reginald Denny]] developed the first scaled remote piloted vehicle in 1935.<ref name="autogenerated1" />\n\nSoviet researchers experimented with controlling [[Tupolev TB-1]] bombers remotely in the late 1930s.<ref>\n{{cite book\n |last1                = Andersson\n |first1               = Lennart\n |title                = Soviet Aircraft and Aviation, 1917-1941\n |url                  = https://books.google.com/books?id=1lzbAAAAMAAJ\n |series               = The Putnam Aviation Series\n |location             = Annapolis, Maryland\n |publisher            = Naval Institute Press\n |publication-date     = 1994\n |page                 = 249\n |isbn                 = 9781557507709\n |access-date          = 18 December 2021\n |quote                = Experiments with a pilotless drone version of the TB-1 controlled by radio from other aircraft started in 1935 and continued until 1939.\n}} \n</ref>\n\n In 1940 Denny started the [[Radioplane Company]] and more models emerged during [[World War II]]{{snd}} used both to train antiaircraft gunners and to fly attack-missions. [[Nazi Germany]] produced and used various UAV aircraft during the war, like the [[Argus As 292]] and the [[V-1 flying bomb]] with a [[jet engine]].\n\n After World War II development continued in vehicles such as the American [[JB-4]] (using television/radio-command guidance), the Australian [[GAF Jindivik]] and [[Ryan Aeronautical |Teledyne Ryan]] [[Ryan Firebee| Firebee I]] of 1951, while companies like [[Beechcraft]] offered their [[Beechcraft MQM-61 Cardinal |Model 1001]] for the [[U.S. Navy]] in 1955.<ref name="autogenerated1" /> Nevertheless, they were little more than remote-controlled airplanes until the [[Vietnam War]].\nIn 1959 the [[U.S. Air Force]], concerned about losing pilots over hostile territory, began planning for the use of uncrewed aircraft.{{sfn|Wagner|1982|p= xi}} Planning intensified after the [[Soviet Union]] [[1960 U-2 incident |shot down a U-2]] in 1960. Within days, a highly-[[classified information|classified]] UAV program started under the code name of "Red Wagon".{{sfn|Wagner|1982|p= xi, xii}} The August 1964 [[Tonkin Gulf Incident|clash in the Tonkin Gulf]] between naval units of the U.S. and the [[North Vietnamese Navy]] initiated America's highly-classified UAVs ([[Ryan Model 147]], [[Ryan AQM-91 Firefly]], [[Lockheed D-21]]) into their first combat missions of the [[Vietnam War]].{{sfn|Wagner|1982|p=xii}} When the Chinese government{{sfn|Wagner|1982|p=79}} showed photographs of downed U.S. UAVs via ''Wide World Photos'',{{sfn|Wagner|1982|p=78, 79}} the official U.S. response was "no comment".\n\nDuring the [[War of Attrition]] (1967\u20131970) in the Middle East, Israeli intelligence tested the first tactical UAVs installed with [[reconnaissance]] cameras, which successfully returned photos from across the Suez Canal. This was the first time that tactical UAVs that could be launched and landed on any short runway (unlike the heavier jet-based UAVs) were developed and tested in battle.<ref>\n{{cite book\n| last1 = Dunstan\n| first1 = Simon\n| title = Israeli Fortifications of the October War 1973\n| url = {{google books |plainurl=y |id=CPm8EocIfoQC|page=16}}\n| publisher = Osprey Publishing\n| date = 2013\n| page = 16\n| isbn = 9781782004318\n| access-date = 25 October 2015\n| quote = The War of Attrition was also notable for the first use of UAVs, or unmanned aerial vehicles, carrying reconnaissance cameras in combat.\n}}\n</ref>\n\nIn the 1973 [[Yom Kippur War]], [[Israel]] used UAVs as decoys to spur opposing forces into wasting expensive anti-aircraft missiles.<ref>\n{{cite book\n| last1 = Saxena\n| first1 = V. K.\n| author-link1 = Corps of Army Air Defence#Director General\n| title = The Amazing Growth and Journey of UAV's and Ballistic Missile Defence Capabilities: Where the Technology is Leading to?\n| url = {{google books |plainurl=y |id=hwWqCQAAQBAJ|page=6}}\n| publisher = Vij Books India Pvt Ltd\n| date = 2013\n| page = 6\n| isbn = 9789382573807\n| access-date = 25 October 2015\n| quote = During the Yom Kippur War the Israelis used Teledyne Ryan 124 R RPVs along with the home-grown Scout and Mastiff UAVs for reconnaissance, surveillance, and as decoys to draw fire from Arab SAMs. This resulted in Arab forces expending costly and scarce missiles on inappropriate targets [...].\n}}\n</ref> After the 1973 Yom Kippur war, a few key people from the team that developed this early UAV joined a small startup company that aimed to develop UAVs into a commercial product, eventually purchased by Tadiran and leading to the development of the first Israeli UAV.<ref>{{cite book |last1= Blum |first1= Howard |title= The eve of destruction: the untold story of the Yom Kippur War |date= 2003 |publisher=HarperCollins |isbn=9780060013998 |language=en}}</ref>{{Pages needed|date=January 2019}}\n\nIn 1973 the U.S. military officially confirmed that they had been using UAVs in Southeast Asia (Vietnam).{{sfn|Wagner|1982|p=202}} Over 5,000 U.S. airmen had been killed and over 1,000 more were [[Missing In Action| missing]] or [[POW|captured]]. The USAF [[100th Strategic Reconnaissance Wing]] flew about 3,435 UAV missions during the war{{sfn|Wagner|1982|p=200, 212}} at a cost of about 554 UAVs lost to all causes. In the words of USAF [[General]] [[George S. Brown]], Commander, [[Air Force Systems Command]], in 1972, "The only reason we need (UAVs) is that we don't want to needlessly expend the man in the cockpit."{{sfn|Wagner|1982|p=208}} Later that year, General [[John C. Meyer]], Commander in Chief, [[Strategic Air Command]], stated, "we let the drone do the high-risk flying ... the loss rate is high, but we are willing to risk more of them ...they save lives!"{{sfn|Wagner|1982|p=208}}\n\nDuring the 1973 [[Yom Kippur War]], Soviet-supplied [[surface-to-air missile]]-batteries in [[Egypt]] and [[Syria]] caused heavy damage to Israeli [[fighter jet]]s. As a result, Israel developed the [[IAI Scout]] as the first UAV with real-time surveillance.<ref>{{cite web\n| url = http://www.howstuffworks.com/reaper1.htm\n| title = A Brief History of UAVs\n| publisher = Howstuffworks.com\n| access-date = 8 January 2015\n| date = 22 July 2008\n}}</ref><ref>{{cite web\n| url = http://www.strategypage.com/htmw/htairfo/articles/20090409.aspx\n| title = Russia Buys A Bunch of Israeli UAVs\n| publisher = Strategypage.com\n| access-date = 8 January 2015\n}}</ref><ref>{{cite web\n| url = http://www.globes.co.il/serveen/globes/docview.asp?did=1000691790\n| title = Unmanned combat vehicles shaping future warfare\n| first = Yuval\n| last = Azoulai\n| date = 24 October 2011\n| work = [[Globes (newspaper)|Globes]]\n| access-date = 8 January 2015\n}}</ref> The images and radar decoys provided by these UAVs helped Israel to [[Operation Mole Cricket 19 | completely neutralize]] the Syrian [[air defense]]s at the start of the [[1982 Lebanon War]], resulting in no pilots downed.<ref name="WSJLevinson">{{cite news\n| url = https://www.wsj.com/articles/SB126325146524725387\n| title = Israeli Robots Remake Battlefield\n| first = Charles\n| last = Levinson\n| date = 13 January 2010\n| work = [[The Wall Street Journal]]\n| page = A10\n| access-date = 13 January 2010\n}}</ref> In Israel in 1987, UAVs were first used as proof-of-concept of super-agility, post-stall controlled flight in combat-flight simulations that involved tailless, stealth-technology-based, three-dimensional thrust vectoring flight-control, and jet-steering.<ref>{{cite book |first = Benjamin |last = Gal-Or |title = Vectored Propulsion, Supermaneuverability & Robot Aircraft |publisher = Springer Verlag |year = 1990 |isbn = 978-3-540-97161-0 }}</ref>\n\n With the maturing and miniaturization of applicable technologies in the 1980s and 1990s, interest in UAVs grew within the higher echelons of the U.S. military. In the 1990s, the U.S. DoD gave a contract to [[AAI Corporation]] along with Israeli company Malat. The U.S. Navy bought the AAI Pioneer UAV that AAI and Malat developed jointly. Many of these UAVs saw service in the [[1991 Gulf War]]. UAVs demonstrated the possibility of cheaper, more capable fighting-machines, deployable without risk to aircrews. Initial generations primarily involved [[surveillance aircraft]], but [[unmanned combat air vehicle|some carried armaments]], such as the [[General Atomics MQ-1 Predator]], that launched [[AGM-114 Hellfire]] [[air-to-ground missile]]s.\n\n[[CAPECON project| CAPECON]], a [[European Union]] [[project]] to develop UAVs,<ref name="Z. Goraj, A. Frydrychewicz, R. \u015awitkiewicz, B. Hernik, J. Gadomski, T. Goetzendorf-Grabowski, M. Figat, St Suchodolski, W. Chajec">{{cite book |url=http://bulletin.pan.pl/(52-3)173.pdf|author1=Z. Goraj |author2= A. Frydrychewicz |author3=R. \u015awitkiewicz |author4=B. Hernik |author5=J. Gadomski |author6=T. Goetzendorf-Grabowski |author7=M. Figat |author8=St Suchodolski |author9=W. Chajec |title= report |publisher= Bulletin of the Polish Academy of Sciences, Technical Sciences, Volume 52. Number 3, 2004|access-date=9 December 2015}}</ref> ran from 1 May 2002 to 31 December 2005.<ref name="CORDIS">{{cite book |url=http://cordis.europa.eu/project/rcn/63495_en.html|author=Community Research and Development Information Service|title=Civil uav application and economic effectiveness of potential configuration solutions|publisher=published by the Publications Office of the European Union|access-date= 9 December 2015|author-link=Community Research and Development Information Service}}</ref>\n\n{{As of | 2012}} the [[United States Air Force]] (USAF) employed 7,494 UAVs{{snd}} almost one in three USAF aircraft.<ref name="WIRED">{{cite news|url= https://www.wired.com/2012/01/drone-report/|title= Almost 1 in 3 U.S. Warplanes Is a Robot|work= WIRED |access-date= 8 January 2015 |first1= Spencer |last1= Ackerman|first2= Noah|last2= Shachtman|date= 9 January 2012}}</ref><ref name="Singer" /> The [[Central Intelligence Agency]] [[Use of UAVs by the CIA| also operated UAVs]].<ref>{{cite journal|last= Radsan|first= AJ|author2= Murphy|title= Measure Twice, Shoot Once: Higher Care for Cia-Targeted Killing|journal= Univ. Ill. Law Rev.:1201\u20131241|year= 2011}}</ref> By 2013 at least 50 countries used UAVs. China, Iran, Israel, Pakistan, Turkey, and others{{which|date=December 2020}} designed and built their own varieties. The use of drones has continued to increase.<ref name="sayler">Sayler (2015)</ref> Due to their wide proliferation, no comprehensive list of UAV systems exists.<ref name="Singer">Singer, Peter W. [http://www.brookings.edu/articles/2009/11_robotic_revolution_singer.aspx "A Revolution Once More: Unmanned Systems and the Middle East"] {{webarchive|url= https://web.archive.org/web/20110806065520/http://www.brookings.edu/articles/2009/11_robotic_revolution_singer.aspx |date=6 August 2011 }}, [http://www.brookings.edu/ The Brookings Institution], November 2009.</ref><ref name="Franke">Franke, Ulrike Esther ["The global diffusion of unmanned aerial vehicles (UAVs) or 'drones'"], in Mike Aaronson (ed) Precision Strike Warfare and International Intervention, Routledge 2015.</ref>\n\nThe development of smart technologies and improved electrical-power systems led to a parallel increase in the use of drones for consumer and general aviation activities. As of 2021, [[quadcopter]] drones exemplify the widespread popularity of hobby [[radio-controlled aircraft]] and toys, however the use of UAVs in commercial and general aviation is limited by a lack of autonomy{{huh?|date=December 2021}} and by new regulatory environments which require line-of-sight contact with the pilot.{{cn|date=December 2021}}\n\nIn 2020 a [[STM Kargu| Kargu 2]] drone hunted down and attacked a human target in [[Libya]], according to a report from the [[UN Security Council]]\u2019s Panel of Experts on Libya, published in March 2021. This may have been the first time an [[:Lethal_autonomous_weapon |autonomous killer-robot]] armed with lethal weaponry attacked human beings.<ref>{{Cite web|last= Hambling|first= David|title= Drones may have attacked humans fully autonomously for the first time|url= https://www.newscientist.com/article/2278852-drones-may-have-attacked-humans-fully-autonomously-for-the-first-time/|access-date=2021-05-30|website= New Scientist|language= en-US}}</ref><ref>\n{{Cite web\n|date= 2021-05-29\n|title= Killer drone 'hunted down a human target' without being told to\n|url= https://www.foxnews.com/world/killer-drone-hunted-down-a-human-target-without-being-told-to\n|access-date=2021-05-30|website=New York Post|language=en-US\n}}\n</ref>\n\nSuperior drone technology played a role in Azerbaijan's successes in the [[2020 Nagorno-Karabakh war]] against Armenia.<ref>\n{{cite news\n| last1                 = Forestier-Walker\n| first1                = Robin\n| title                 = Nagorno-Karabakh: New weapons for an old conflict spell danger\n| url                   = https://www.aljazeera.com/features/2020/10/13/nagorno-karabakh-new-weapons-for-an-old-conflict-spell-danger\n| publisher             = Al Jazeera\n| publication-date      = 13 October 2020\n| access-date           = 18 December 2021\n| quote                 = [...] battlefield videos and the known military capabilities of the two warring sides suggest Azerbaijan has the technological advantage, especially with its combat drones purchased from Israel and Turkey.\n}}\n</ref>"}},
{"article_title": "Timeline of telescopes, observatories, and observing technology", "pageid": "58953", "revid": "1059842891", "timestamp": "2021-12-11T23:58:44Z", "history_paths": [["Timeline of telescopes, observatories, and observing technology --- Introduction ---", "Before the Common Era (BCE)"], ["Timeline of telescopes, observatories, and observing technology --- Introduction ---", "Common Era (CE)"]], "categories": ["technology timelines", "astronomy timelines", "astronomical observatories", "astronomical imaging", "observational astronomy", "telescopes"], "heading_tree": {"Timeline of telescopes, observatories, and observing technology --- Introduction ---": {"Before the Common Era (BCE)": {"3500s BCE": {}, "1900s BCE": {}, "1500s BCE": {}, "600s BCE": {}, "200s BCE": {}, "100s BCE": {}}, "Common Era (CE)": {"400s": {}, "500s": {}, "600s": {}, "700s": {}, "800s": {}, "900s": {}, "1000s": {}, "1100s": {}, "1200s": {}, "1300s": {}, "1400s": {}, "1500s": {}, "1600s": {}, "1700s": {}, "1800s": {}, "1900s": {"1910s": {}, "1930s": {}, "1940s": {}, "1950s": {}, "1960s": {}, "1970s": {}, "1980s": {}, "1990s": {}}, "2000s": {}}, "Under Construction": {}, "Planned": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Timeline of telescopes, observatories, and observing technology --- Introduction ---|Before the Common Era (BCE)": "* The earliest [[sundial]]s known from the archaeological record are the [[obelisks]] from ancient [[Egyptian astronomy]] and [[Babylonian astronomy]]\n\n * [[Taosi]] Astronomical Observatory, [[Xiangfen]] County, [[Linfen]] City, [[Shanxi]] Province, China\n\n * [[Shadow clock]]s invented in [[ancient Egypt]] and [[Mesopotamia]]\n\n * 11th\u20137th century BCE, [[Zhou dynasty]] astronomical observatory (\u7075\u53f0) in today's [[Xian]], China\n\n * Thirteen Towers solar observatory, [[Chankillo]], [[Peru]]\n\n * 220-206 BCE, [[Han dynasty]] astronomical observatory ([[\u7075\u53f0]]) in [[Chang'an]] and [[Luoyang]]. During [[Han dynasty|East Han dynasty]], astronomical observatory (\u7075\u53f0) built in [[Yanshi]], [[Henan]] Province, China\n* 220-150 BCE, [[Astrolabe]] invented by [[Apollonius of Perga]]", "Timeline of telescopes, observatories, and observing technology --- Introduction ---|Common Era (CE)": "* 5th century \u2013 Observatory at [[Ujjain]], [[India]]\n* 5th century \u2013 ''[[Surya Siddhanta]]'' written in India\n* 499 \u2013 ''[[Aryabhatiya]]'' written by [[Aryabhata]]\n\n * 6th century \u2013 Various [[siddhanta]]s compiled by [[Indian astronomy|Indian astronomers]]\n\n * c. 628 \u2013 ''[[Brahmasphutasiddhanta]]'' by [[Brahmagupta]]\n* 632\u2013647 \u2013 [[Cheomseongdae]] observatory is built in the reign of [[Queen Seondeok]] at [[Gyeongju]], then the capital of [[Silla]] (present day [[South Korea]])\n* 618\u20131279 \u2013 [[Tang dynasty]]-[[Song dynasty]], observatories built in [[Chang'an]], [[Kaifeng]], [[Hangzhou]], China\n\n * 700\u201377 \u2013 The first [[Zij]] treatise, ''Az-Z\u012bj \u201bal\u0101 Sin\u012b al-\u201bArab'', written by [[Ibrahim al-Fazari]] and [[Muhammad al-Fazari]]\n* 700\u201396 \u2013 Brass [[astrolabe]] constructed by [[Muhammad al-Fazari]] based on [[Hellenistic civilization|Hellenistic]] sources\n* c. 777 \u2013 [[Yaq\u016bb ibn T\u0101riq]] wrote ''Az-Zij al-Mahlul min as-Sindhind li-Darajat Daraja'' based on [[Brahmagupta]] and ''[[Surya Siddhanta]]''\n\n * 9th century \u2013 [[Quadrant (instrument)|quadrant]] invented by [[Muhammad ibn M\u016bs\u0101 al-Khw\u0101rizm\u012b]] in 9th century [[Baghdad]] and is used for astronomical calculations<ref name="King-2002">{{Citation |last=King |first=David A. |year=2002 |title=A Vetustissimus Arabic Text on the Quadrans Vetus |journal=Journal for the History of Astronomy |volume=33 |issue=112 |pages=237\u2013255 [237\u20138]|bibcode = 2002JHA....33..237K |doi=10.1177/002182860203300302 }}</ref>\n* 800\u201333 \u2013 The first modern [[observatory]] research institute built in [[Baghdad]], [[Iraq]], by [[Astronomy in medieval Islam|Arabic astronomers]] during time of [[Al-Mamun]]<ref>{{Citation |last=Kennedy |first=Edward S. |year=1962 |title=Review: ''The Observatory in Islam and Its Place in the General History of the Observatory'' by Aydin Sayili |journal=[[Isis (journal)|Isis]] |volume=53 |issue=2 |pages=237\u2013239 |doi=10.1086/349558 }}</ref>\n* 800\u201350 \u2013 ''[[Zij|Zij al-Sindhind]]'' written by [[Muhammad ibn M\u016bs\u0101 al-Khw\u0101rizm\u012b]] (Algorismi)\n* 825\u201335 \u2013 [[Astronomy in medieval Islam#Observatories|Al-Shammisiyyah observatory]] by [[Habash al-Hasib al-Marwazi]] in Baghdad, Iraq<ref name="Langermann">{{citation|title=The Book of Bodies and Distances of Habash al-Hasib|last=Langermann|first=Y. Tzvi|journal=[[Centaurus (journal)|Centaurus]]|year=1985|volume=28|issue=2|pages=108\u2013128 [112]|doi=10.1111/j.1600-0498.1985.tb00831.x|bibcode = 1985Cent...28..108T }}</ref>\n* 869 \u2013 [[Kodungallur|Mahodayapuram]] Observatory in [[Kerala]], [[India]], by [[Sankaranarayana]]\n\n * 10th century \u2013 Large [[astrolabe]] of diameter 1.4 meters constructed by [[Ibn Yunus]]{{Citation needed|date=May 2010}}\n* 900\u201329 \u2013 ''[[Zij|Az-Zij as-Sabi]]'' written by [[Muhammad ibn J\u0101bir al-Harr\u0101n\u012b al-Batt\u0101n\u012b]] (Albatenius)\n* 994 \u2013 First [[Sextant (astronomical)|sextant]] constructed in [[Ray, Iran]], by [[Abu-Mahmud al-Khujandi]]. It was a very large [[Mural instrument|mural]] sextant that achieved a high level of accuracy for astronomical measurements.<ref>{{MacTutor|id=Al-Khujandi|title=Al-Khujandi}}</ref>\n\n * 1000 \u2013 [[Mokattam]] observatory in [[Egypt]] for [[Al-Hakim bi-Amr Allah]]\n* 1000 \u2013 [[Volvelle]], an early paper [[analog computer]], invented by [[Medicine in medieval Islam|Arabic physicians]]<ref>{{citation|title=On the Origin of Polyalphabetic Substitution|author=David Kahn|journal=[[Isis (journal)|Isis]]|volume=71|issue=1|date=March 1980|publisher=[[University of Chicago Press]]|jstor=230316|pages=122\u2013127 [126]|author-link=David Kahn (writer)|doi=10.1086/352410}}</ref> and improved by [[Abu Rayhan Biruni]] for use in astronomy.<ref>{{citation|title=State, Science and Economy in Traditional Societies: Some Problems in Weberian Sociology of Science|author=Bryan S. Turner|journal=British Journal of Sociology|volume=38|issue=1|date=March 1987|publisher=[[Wiley-Blackwell (publisher)|Blackwell Publishing]]|jstor=590576|pages=1\u201323 [12]|author-link=Bryan S. Turner (sociologist)|doi=10.2307/590576}}</ref>\n* 11th century \u2013 [[Planisphere]] invented by Biruni<ref>[[Will Durant]] (1950). ''[[The Story of Civilization]] IV: The Age of Faith'', pp. 239\u201345.</ref>\n* 11th century \u2013 Universal latitude-independent [[astrolabe]] invented by [[Ab\u016b Ish\u0101q Ibr\u0101h\u012bm al-Zarq\u0101l\u012b]] (Arzachel)<ref>{{cite book |title=The History of Cartography: Cartography in the traditional Islamic and South Asian societies |volume = 2| year = 1992| publisher = [[Oxford University Press]]| isbn = 0-226-31635-1| pages = 28\u20139 |author1=John Brian Harley |author2=David Woodward |author3=G. Malcolm Lewis}}</ref>\n* 1015 \u2013 [[Equatorium]] invented by Arzachel in [[Al-Andalus]]<ref>{{Citation |last=Hassan |first=Ahmad Y. |author-link=Ahmad Y Hassan |url=http://www.history-science-technology.com/Articles/articles%2071.htm |title=Transfer Of Islamic Technology To The West, Part II: Transmission Of Islamic Engineering |access-date=2008-01-22 }}</ref>\n* 1023 \u2013 [[Hamedan]] observatory in [[Iran|Persia]]\n* c. 1030 \u2013 ''[[Book of Optics|Treasury of Optics]]'' by [[Ibn al-Haytham]] (Alhazen) of Iraq and Egypt\n* 1074\u201392 \u2013 [[Malikshah Observatory]] at [[Isfahan]] used by [[Omar Khayy\u00e1m]]\n* 1086 \u2013 [[Northern Song dynasty]] astronomical observatory\n\n * 1100\u201350 \u2013 [[Jabir ibn Aflah]] (Geber) (c. 1100\u20131150) invented the [[torquetum]], an observational instrument and mechanical [[analog computer]] device<ref>{{citation|first=R. P.|last=Lorch|title=The Astronomical Instruments of Jabir ibn Aflah and the Torquetum|journal=[[Centaurus (journal)|Centaurus]]|volume=20|issue=1|year=1976|pages=11\u201334|doi=10.1111/j.1600-0498.1976.tb00214.x|bibcode = 1976Cent...20...11L }}</ref>\n* 1114\u201387 \u2013 ''[[Tables of Toledo]]'' based on Arzachel and published by [[Gerard of Cremona]]\n* 1115\u201316 \u2013 ''Sinjaric Tables'' written by [[al-Khazini]]\n* 1119\u201325 \u2013 [[Cairo]] al-Bataihi observatory for [[Al-Afdal Shahanshah]]\n* cs. 1020 \u2013 [[Gear]]ed mechanical [[astrolabe]] invented by Ibn Samh\n\n * 1206 \u2013 [[Al-Jazari]] invented his largest [[astronomical clock]], the "[[castle clock]]", which is considered to be the first [[Computer programming|programmable]] [[analog computer]].<ref name="Ancient Discoveries">{{citation|title=Ancient Discoveries, Episode 11: Ancient Robots|publisher=[[History (U.S. TV channel)|History Channel]]|url=https://www.youtube.com/watch?v=rxjbaQl0ad8 |url-status=dead|access-date=2008-09-06}}</ref>\n* 1252\u201372 \u2013 ''[[Alfonsine tables]]'' recorded\n* 1259 \u2013 [[Maragheh observatory]] and library of [[Nasir al-Din al-Tusi]] built in Persia under [[Hulagu Khan]]\n* c. 1270 \u2013 Terrace for Managing Heaven 26 observatory network of [[Guo Shoujing]] under [[Khubilai Khan]]\n* 1272 \u2013 ''[[Zij-i Ilkhani]]'' written by [[Nasir al-Din al-Tusi]]\n* 1276 \u2013 [[Gaocheng Astronomical Observatory|Dengfeng Star Observatory Platform]], Gaocheng, [[Dengfeng]] City, [[Henan]] Province, China\n\n * 1371 \u2013 The idea of using hours of equal time length throughout the year in a [[sundial]] was the innovation of [[Ibn al-Shatir]]<ref>{{cite web|title=History of the sundial|url=http://www.nmm.ac.uk/server/show/conWebDoc.353|publisher=[[National Maritime Museum]]|access-date=2008-07-02|url-status=dead|archive-url=https://web.archive.org/web/20071010044606/http://www.nmm.ac.uk/server/show/conWebDoc.353|archive-date=2007-10-10}}</ref><ref>{{citation|title=The Sundial And Geometry|first=Lawrence|last=Jones|journal=North American Sundial Society|volume=12|issue=4|date=December 2005}}</ref>\n\n * 1400\u201329 \u2013 ''[[Zij|Khaqani Zij]]'' by [[Jamsh\u012bd al-K\u0101sh\u012b]]\n* 1417 \u2013 ''Speculum Planetarum'' by Simones de Selandia\n* 1420 \u2013 [[Ulugh Beg Observatory|Samarkand observatory]] of [[Ulugh Beg]]\n* 1437 \u2013 ''[[Zij-i-Sultani]]'' written by [[Ulugh Beg]]\n* 1442 \u2013 [[Beijing Ancient Observatory]] in China\n* 1467\u201371 \u2013 Observatory at [[Oradea]], Hungary for [[Matthias Corvinus]]\n* 1472 \u2013 The [[Nuremberg]] observatory of [[Regiomontanus]] and [[Bernhard Walther]].<ref>{{cite book|last=Pedersen|first=Olaf|title=A Survey of the Almagest|url=https://archive.org/details/surveyalmagest00pede|url-access=limited|year=2010|publisher=Springer|isbn=978-0387848259|pages=[https://archive.org/details/surveyalmagest00pede/page/n20 20]}}</ref>\n\n * 1540 [[Petrus Apianus|Apian]] ''[[Astronomicum Caesareum]]''\n* 1560 \u2013 [[Kassel]] observatory under Landgrave [[William IV of Hesse|Wilhelm IV of Hesse]]\n* 1574 \u2013 [[Taqi al-Din Muhammad ibn Ma'ruf]] describes a long-distance [[Magnification|magnifying]] device in his ''Book of the Light of the Pupil of Vision and the Light of the Truth of the Sights'', which may have possibly been an early rudimentary [[telescope]].<ref>{{Cite web|date=2008-07-15|title=Taqi al-Din ibn Ma\u2018ruf and the Science of Optics: The Nature of Light and the Mechanism of Vision|url=https://muslimheritage.com/taqi-al-din-sci-optics-light-vision/|access-date=2021-03-21|website=Muslim Heritage}}</ref>\n* 1575\u201380 \u2013 [[Constantinople Observatory of Taqi ad-Din]] under Sultan [[Murad III]]\n* 1576 \u2013 Royal Danish Astronomical Observatory [[Uraniborg]] at [[Hven]] by [[Tycho Brahe]]\n* 1577 \u2013 [[Constantinople]] observatory constructed for Taqi al-Din Muhammad ibn Ma'ruf\n* 1577\u201380 \u2013 ''Unbored Pearl'', a [[Zij]] treatise by Taqi al-Din\n* 1577\u201380 \u2013 Taqi al-Din invents a mechanical [[astronomical clock]] that measures time in seconds, one of the most important innovations in 16th-century practical astronomy, as previous clocks were not accurate enough to be used for astronomical purposes.<ref name="Tekeli">{{cite encyclopedia | first = Sevim | last = Tekeli | title = Taqi al-Din | year = 1997 | encyclopedia = Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures | publisher = [[Kluwer Academic Publishers]] | isbn = 0-7923-4066-3 | url = https://www.springer.com/philosophy/philosophy+of+sciences/book/978-1-4020-4425-0 }}</ref>\n* 1577\u201380 \u2013 Taqi al-Din invents [[Sextant (astronomical)|framed sextant]]<ref name=Tekeli/>\n* 1581 \u2013 Royal Danish Astronomical Observatory [[Stjerneborg]] at [[Hven]] by [[Tycho Brahe]]\n* 1589\u201390 \u2013 [[Celestial globe]] without [[Seam (metallurgy)|seams]] invented in [[Mughal India]] by Ali Kashmiri ibn Luqman during [[Akbar the Great]]'s reign.<ref>{{citation|first=Emilie|last=Savage-Smith|title=Islamicate Celestial Globes: Their History, Construction, and Use|publisher=Smithsonian Institution Press, Washington, D.C.|year=1985}}</ref>\n\n * 1600 \u2013 Prague observatory in [[Ben\u00e1tky nad Jizerou]] by [[Tycho Brahe]]\n* 1603 \u2013 [[Johann Bayer]]'s ''[[Uranometria]]'' is published\n* 1608 \u2013 [[Hans Lippershey]] tries to patent an optical [[refracting telescope]], the first recorded functional [[telescope]]\n* 1609 \u2013 [[Galileo Galilei]] builds his first optical refracting telescope\n* 1616 \u2013 [[Niccol\u00f2 Zucchi]] experiments with a [[reflecting telescope]]\n* 1633 \u2013 Construction of [[Leiden Observatory|Leiden University Observatory]]\n* 1641 \u2013 [[William Gascoigne (scientist)|William Gascoigne]] invents telescope cross hairs\n* 1641 \u2013 Danzig/Gdansk observatory of [[Johannes Hevelius|Jan Hevelius]]\n* 1642  \u2013 [[Rundet\u00e5rn|Copenhagen University Royal observatory]]\n* 1661 \u2013 [[James Gregory (astronomer and mathematician)|James Gregory]] proposes an optical reflecting telescope with [[Parabolic reflector|parabolic]] mirrors\n* 1667 \u2013 [[Paris Observatory]]\n* 1668 \u2013 [[Isaac Newton]] constructs the first "practical" reflecting telescope, the [[Newtonian telescope]]<ref name="books.google.com">{{cite book|author=A. Rupert Hall|title=Isaac Newton: Adventurer in Thought|url=https://archive.org/details/isaacnewtonadven0000hall|url-access=registration|year=1996|publisher=Cambridge University Press|isbn=978-0-521-56669-8|page=[https://archive.org/details/isaacnewtonadven0000hall/page/67 67]}}</ref>\n* 1672 \u2013 [[Laurent Cassegrain]] designs the Cassegrain telescope\n* 1675 \u2013 [[Royal Greenwich Observatory]] of England\n* 1684 \u2013 [[Christiaan Huygens]] publishes "Astroscopia Compendiaria" in which he described the design of very long [[aerial telescope]]s\n\n * 1704 \u2013 First observatory at [[University of Cambridge|Cambridge University]] (based at [[Trinity College, Cambridge|Trinity College]])\n* 1724 \u2013 Indian observatory of [[Jai Singh II|Sawai Jai Singh]] at [[Delhi]]\n* 1725 \u2013 St. Petersburg observatory at Royal Academy\n* 1732 \u2013 Indian observatories of Sawai Jai Singh at [[Varanasi]], [[Ujjain]], [[Mathura]], [[Madras]]\n* 1733 \u2013 [[Chester Moore Hall]] invents the [[achromatic lens]] refracting telescope\n* 1734 \u2013 Indian observatory of Sawai Jai Singh at [[Jaipur]]\n* 1753 \u2013 Real Observatorio de C\u00e1diz (Spain)\n* 1753 \u2013 [[Vilnius Observatory]] at [[Vilnius University]], [[Lithuania]]\n* 1758 \u2013 [[John Dollond]] reinvents the achromatic lens\n* 1761 \u2013 [[Joseph-Nicolas Delisle]] 62 observing station network for observing the [[transit of Venus]]\n* 1769 \u2013 [[James Short (mathematician)|Short]] reflectors used at 63 station network for [[transit of Venus]]\n* 1774 \u2013 [[Vatican Observatory|Vatican Observatory ''(Specola Vaticana)'']], originally established as ''the Observatory of the Roman College''. \n* 1780  \u2013 [[Florence]] [[La Specola|Specola]] observatory\n* 1789 \u2013 [[William Herschel]] finishes a 49-inch (1.2 m) optical reflecting telescope, located in [[Slough]], England\n* 1798 \u2013 Real Observatorio de la Isla de L\u00e9on (actualmente Real Instituto y Observatorio de la Armada) (Spain)\n\n *1803 [[National Astronomical Observatory (Colombia)]], the first observatory in the [[Americas]]<ref>{{Cite journal|last=Keenan|first=Philip C.|date=February 1, 1991|title=The Earliest National Observatories in Latin America|journal=Journal for the History of Astronomy|volume=22|issue=1|pages=21\u201330|bibcode=1991JHA....22...21K|doi=10.1177/002182869102200104}}</ref>\n*1836 Swathithirunal opened Trivandrum observatory\n*1839 [[Louis Jacques Mand\u00e9 Daguerre]] (inventor of the [[daguerreotype]] photographic process) attempts in  to photograph the [[moon]]. Tracking errors in guiding the telescope during the long exposure made the photograph came out as an indistinct fuzzy spot\n* 1840 \u2013 [[John William Draper]] takes make a successful photographic image of the [[Moon]], the first [[astrophotography|astronomical photograph]]\n* 1845 \u2013 [[William Parsons, 3rd Earl of Rosse|Lord Rosse]] finishes the Birr Castle [[Leviathan of Parsonstown|{{convert|72|in|m|adj=on}} optical reflecting telescope]], located in [[Birr, County Offaly|Parsonstown, Ireland]]\n* 1849 \u2013 Santiago observatory set up by USA, later becomes Chilean National Observatory (now part of the [[University of Chile]])<ref>[http://home.earthlink.net/~claelliott/chron1840.htm Chronology of Science in the United States 1840\u20131849 (derived from ''Clark A. Elliott, History of Science in the United States: A Chronology and Research Guide'' \u2013 New York and London: Garland Publishing, 1996, pp. 34\u2013177)].</ref>\n* 1859 \u2013  [[Gustav Kirchhoff|Kirchhoff]] and [[Robert Bunsen|Bunsen]] develop [[spectroscopy]]\n* 1864 \u2013 [[Alexander Stewart Herschel|Herschel]]'s so-called GC (General Catalogue) of nebulae and star clusters published\n* 1868 \u2013  [[Pierre Jules C\u00e9sar Janssen|Janssen]] and [[Joseph Norman Lockyer|Lockyer]] discover [[Helium]] observing spectra of [[Sun]]\n* 1871 \u2013 [[Astronomische Gesellschaft|German Astronomical Association]] organized network of 13 (later 16) observatories for stellar proper motion studies\n* 1863 \u2013 [[William Allen Miller]] and Sir [[William Huggins]] use the photographic [[Wet plate|wet collodion plate]] process to obtain the first ever photographic [[spectrogram]] of a star, [[Sirius]] and [[Capella (star)|Capella]].<ref name="astro-canada.ca">[http://astro-canada.ca/_en/a2311.html Spectrometers, ASTROLab of Mont-M\u00e9gantic National Park]</ref>\n* 1872 \u2013 [[Henry Draper]] photographs a [[optical spectrum|spectrum]] of [[Vega]] that shows [[absorption lines]].<ref name="astro-canada.ca"/>\n* 1878 \u2013 [[John Louis Emil Dreyer|Dreyer]] published a supplement to the GC of about 1000 new objects, the [[New General Catalogue]]\n* 1883 \u2013 [[Andrew Ainslie Common]] uses the photographic [[dry plate]] process and a 36-inch (91 cm) reflecting telescope in his backyard to record 60 minute exposures of the [[Orion nebula]] that for the first time showed stars too faint to be seen by the human eye.<ref>{{cite book| author = J. B. Hearnshaw| title = The Measurement of Starlight: Two Centuries of Astronomical Photometry| url = https://archive.org/details/measurementofsta0000hear| url-access = registration| date = 1996-05-02| publisher = Cambridge University Press| isbn = 978-0-521-40393-1| page = [https://archive.org/details/measurementofsta0000hear/page/122 122] }}</ref>\n* 1887 \u2013  Paris conference institutes ''[[Carte du Ciel]]'' project to map entire sky to 14th magnitude photographically\n* 1888 \u2013  First light of [[James Lick telescope|91cm refracting telescope]] at [[Lick Observatory]], on [[Mount Hamilton (California)|Mount Hamilton]] near [[San Jose, California]]\n* 1889 \u2013  [[Astronomical Society of the Pacific]] founded\n* 1890 \u2013 [[Albert A. Michelson]] proposes the stellar [[interferometer]]\n* 1892 \u2013 [[George Ellery Hale]] finishes a [[spectroheliograph]], which allows the [[Sun]] to be photographed in the light of one element only\n* 1897 \u2013 [[Alvan Clark]] finishes the [[Yerkes telescope|Yerkes {{convert|40|in|m|adj=on}} optical refracting telescope]], located in [[Williams Bay, Wisconsin]]\n\n * 1902 \u2013 [[Dominion Observatory]], Ottawa, Ontario, Canada established\n* 1904 \u2013 Observatories of the [[Carnegie Institution]] of Washington founded\n* 1907 \u2013 F.C. Brown and [[Joel Stebbins]] develop a selenium cell photometer at the [[University of Illinois Observatory]].\n\n * 1912 \u2013 [[Joel Stebbins]] and Jakob Kunz begin to use a photometer using a photoelectric cell at the [[University of Illinois Observatory]].\n* 1917 \u2013 Mount Wilson {{convert|100|in|m|adj=on}} optical reflecting telescope begins operation, located in [[Mount Wilson Observatory|Mount Wilson, California]]\n* 1918 \u2013 1.8m Plaskett Telescope begins operation at the [[Dominion Astrophysical Observatory]], [[Victoria, British Columbia|Victoria]], [[British Columbia]], Canada\n* 1919 \u2013 [[International Astronomical Union]] (IAU) founded\n\n \n* 1930 \u2013 [[Bernard-Ferdinand Lyot]] invents the [[coronagraph]]\n* 1930 \u2013 [[Karl Jansky]] builds a 30-meter long rotating aerial [[radio telescope]] This was the first radio telescope.\n* 1933 \u2013 [[Bernard-Ferdinand Lyot]] invents the [[Lyot filter]]\n* 1934 \u2013 [[Bernhard Schmidt]] finishes the first {{convert|14|in|mm|adj=on}} [[Schmidt camera|Schmidt optical reflecting telescope]]\n* 1936 \u2013 Palomar {{convert|18|in|mm|adj=on}} Schmidt optical reflecting telescope begins operation, located in [[Mount Palomar observatory|Palomar, California]]\n* 1937 \u2013 [[Grote Reber]] builds a {{convert|31|ft|m|adj=on}} radio telescope\n\n \n* 1941 \u2013 [[Dmitri Dmitrievich Maksutov]] invents the [[Maksutov telescope]] which is adopted by major observatories in the [[Soviet Union]] and internationally. It is now also a popular design with [[Amateur astronomy|amateur astronomers]]\n* 1946 \u2013 [[Martin Ryle]] and his group perform the first astronomical observations with a radio interferometer\n* 1947 \u2013 [[Bernard Lovell]] and his group complete the [[Jodrell Bank]] {{convert|218|ft|m|adj=on}} non-steerable radio telescope\n* 1949 \u2013 [[Samuel Oschin telescope|Palomar {{convert|48|in|m|adj=on}} Schmidt]] optical reflecting telescope begins operation, located in Palomar, California\n* 1949 \u2013 Palomar {{convert|200|in|m|adj=on}} optical reflecting telescope ([[Hale telescope]]) begins regular operation, located in Palomar, California\n\n \n* 1953 \u2013 [[Luoxue Mountain Cosmic Rays Research Center]], [[Yunnan]] Province, in China founded\n* 1954 \u2013 Earth rotation [[aperture synthesis]] suggested (see e.g. Christiansen and Warburton (1955))\n* 1956 \u2013 [[Dwingeloo Radio Observatory]] 25 m telescope completed, [[Dwingeloo]], [[Netherlands]]\n* 1957 \u2013 [[Bernard Lovell]] and his group complete the [[Jodrell Bank]] 250-foot (75 m) steerable radio telescope (the [[Lovell Telescope]])\n* 1957 \u2013 [[Peter Scheuer]] publishes his P(D) method for obtaining [[source counts]] of spatially unresolved sources\n* 1959 \u2013 Radio Observatory of the [[University of Chile]], located at [[Maip\u00fa, Chile]] founded\n* 1959 \u2013 The [[Third Cambridge Catalogue of Radio Sources|3C]] catalogue of radio sources is published (revised in 1962)\n* 1959 \u2013 The [[C. Donald Shane telescope|Shane {{convert|120|in|m|adj=on}} Telescope]] Opened at [[Lick Observatory]]\n\n \n* 1960 \u2013 [[Owens Valley Radio Observatory|Owens Valley]] 27-meter radio telescopes begin operation, located in [[Big Pine, California]]\n* 1961 \u2013 [[Parkes Observatory|Parkes 64-metre radio telescope]] begins operation, located near [[Parkes, New South Wales|Parkes]], Australia\n* 1962 \u2013 [[European Southern Observatory]] (ESO) founded\n* 1962 \u2013  [[McMath-Pierce Solar Telescope|Kitt Peak solar observatory]] founded\n* 1962 \u2013 [[Green Bank, West Virginia]] 90m radio telescope\n* 1962 \u2013 [[Orbiting Solar Observatory]] 1 satellite launched\n* 1963 \u2013 [[Arecibo radio telescope|Arecibo 300-meter radio telescope]] begins operation, located in [[Arecibo, Puerto Rico]]\n* 1964 \u2013 [[Martin Ryle]]'s {{convert|1|mi|km|adj=on}} radio [[interferometer]] begins operation, located in [[Cambridge, England]]\n* 1965 \u2013 Owens Valley 40-meter radio telescope begins operation, located in [[Big Pine, California]]\n* 1967 \u2013 First [[VLBI]] images, with 183 km [[Astronomical interferometer|baseline]]\n* 1969 \u2013 Observations start at [[Big Bear Solar Observatory]], located in [[Big Bear, California]]\n* 1969 \u2013 [[Las Campanas Observatory]]\n\n \n* 1970 \u2013 [[Cerro Tololo telescope|Cerro Tololo {{convert|158|in|m|adj=on}} optical reflecting telescope]] begins operation, located in [[Cerro Tololo]], [[Chile]]\n* 1970 \u2013 [[Kitt Peak National Observatory]] {{convert|158|in|m|adj=on}} optical reflecting telescope begins operation, located near [[Tucson, Arizona]]\n* 1970 \u2013 [[Uhuru (satellite)|Uhuru]] x-ray telescope satellite\n* 1970 \u2013 [[Antoine \u00c9mile Henry Labeyrie|Antoine Labeyrie]] performs the first high-resolution optical [[Speckle imaging|speckle interferometry]] observations\n* 1970 \u2013 [[Westerbork Synthesis Radio Telescope]] completed, near [[Westerbork (village)|Westerbork]], [[Netherlands]]\n* 1972 \u2013 100 m [[Effelsberg]] radio telescope inaugurated ([[Germany]])\n* 1973 \u2013 [[UK Schmidt Telescope]] 1.2 metre optical reflecting telescope begins operation, located in [[Anglo-Australian Observatory]] near [[Coonabarabran]], Australia\n* 1974 \u2013 [[Anglo-Australian Telescope]] {{convert|153|in|m|adj=on}} optical reflecting telescope begins operation, located in [[Anglo-Australian Observatory]] near [[Coonabarabran]], Australia\n* 1975 \u2013 Gerald Smith, Frederick Landauer, and James Janesick use a [[Charge-coupled device|CCD]] to observe [[Uranus]], the first astronomical CCD observation\n* 1975 \u2013 [[Antoine \u00c9mile Henry Labeyrie|Antoine Labeyrie]] builds the first two-telescope optical [[interferometer]]\n* 1976 \u2013 The 6-m [[BTA-6]] (Bolshoi Teleskop Azimutalnyi or \u201cLarge Altazimuth Telescope\u201d) goes into operation on Mt. Pashtukhov in the Russian Caucasus\n* 1978 \u2013 Multiple Mirror {{convert|176|in|m|adj=on}} equivalent optical/infrared reflecting telescope begins operation, located in [[Amado, Arizona]]\n* 1978 \u2013 [[International Ultraviolet Explorer]] (IUE) telescope satellite\n* 1978  \u2013 [[Einstein Observatory|Einstein High Energy Astronomy Observatory]] x-ray telescope satellite\n* 1979 \u2013 [[UKIRT]] {{convert|150|in|m|adj=on}} infrared reflecting telescope begins operation, located at [[Mauna Kea Observatory]], Hawaii\n* 1979 \u2013 [[Canada-France-Hawaii Telescope|Canada-France-Hawaii]] {{convert|140|in|m|adj=on}} optical reflecting telescope begins operation, located at [[Mauna Kea Observatory]], Hawaii\n* 1979 \u2013 [[NASA Infrared Telescope Facility]][http://irtfweb.ifa.hawaii.edu/] {{convert|120|in|m|adj=on}} infrared reflecting telescope begins operation, located at Mauna Kea, Hawaii\n\n \n* 1980 \u2013 Completion of construction of the [[Very Large Array|VLA]], located in [[Socorro, New Mexico]]\n* 1983 \u2013 [[Infrared Astronomical Satellite]] (IRAS) telescope\n* 1984 \u2013 [[IRAM 30-m]] telescope at [[Veleta (Sierra Nevada)|Pico Veleta]] near [[Granada]], [[Spain]] completed\n* 1987 \u2013 15-m [[James Clerk Maxwell Telescope]] UK submillimetre telescope installed at [[Mauna Kea Observatory]]\n* 1987 \u2013 5-m Swedish-ESO Submillimetre Telescope (SEST) installed at the ESO [[La Silla Observatory]]\n* 1988 \u2013 [[Australia Telescope Compact Array]] aperture synthesis radio telescope begins operation, located near [[Narrabri]], Australia\n* 1989 \u2013 [[Cosmic Background Explorer]] (COBE) satellite\n\n * 1990 \u2013 [[Hubble Space Telescope|Hubble]] 2.4m space Telescope launched, mirror found to be flawed\n* 1991 \u2013 [[Compton Gamma Ray Observatory]] satellite\n* 1993 \u2013 [[Keck telescope|Keck 10-meter optical/infrared reflecting telescope]] begins operation, located at Mauna Kea, Hawaii\n* 1993 \u2013 [[Very Long Baseline Array]] of 10 dishes\n* 1995 \u2013 [[Cambridge Optical Aperture Synthesis Telescope (COAST)]]\u2014the first very high resolution optical astronomical images (from [[aperture synthesis]] observations)\n* 1995 \u2013 [[Giant Metrewave Radio Telescope]] of thirty 45 m dishes at Pune\n* 1996 \u2013 [[Keck 2]] 10-meter optical/infrared reflecting telescope begins operation, located at Mauna Kea, Hawaii\n* 1997 \u2013 The Japanese [[HALCA]] satellite begins operations, producing first [[VLBI]] observations from space, 25,000 km maximum baseline\n* 1998 \u2013 First light at [[Very Large Telescope|VLT]]1, the 8.2 m [[European Southern Observatory|ESO]] telescope\n\n \n* 2001 \u2013 First light at the [[Keck Interferometer]]. Single-baseline operations begin in the near-infrared.\n* 2001 \u2013 First light at [[VLTI]] interferometry array. Operations on the interferometer start with single-baseline near-infrared observations with the 103 m [[Astronomical interferometer|baseline]].\n* 2005 \u2013 First imaging with the [[VLTI]] using the AMBER optical aperture synthesis instrument and three [[Very Large Telescope|VLT]] telescopes.\n* 2005 \u2013 First light at [[Southern African Large Telescope|SALT]], the largest optical telescope in the Southern Hemisphere, with a primary mirror diameter of 11 meters."}},
{"article_title": "Next-Generation Secure Computing Base", "pageid": "59524", "revid": "1054340260", "timestamp": "2021-11-09T13:24:43Z", "history_paths": [["Next-Generation Secure Computing Base --- Introduction ---", "History"]], "categories": ["cryptographic software", "discontinued windows components", "disk encryption", "microsoft criticisms and controversies", "microsoft initiatives", "microsoft windows security technology", "trusted computing", "windows vista"], "heading_tree": {"Next-Generation Secure Computing Base --- Introduction ---": {"History": {"Early development": {}, "As \"Palladium\"": {}, "As NGSCB": {}}, "Architecture and technical details": {"Secure storage and attestation": {}, "Curtained memory": {}, "Applications": {}}, "Uses and scenarios": {"WinHEC 2004 scenarios": {}}, "Reception": {}, "Vulnerability": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Next-Generation Secure Computing Base --- Introduction ---|History": "[[File:PeterBiddle_eTech07.jpg|200px|thumb|left|Peter Biddle speaks at the ETech conference in 2007.]]\nDevelopment of NGSCB began in 1997 after [[Peter Biddle]] conceived of new ways to protect content on personal computers.<ref name="TheBigSecret"/><ref name="PalladiumSummary">{{cite web|url=http://vitanuova.loyalty.org/2002-07-05.html |title=Palladium summary |last=Schoen |first=Seth |author-link=Seth Schoen |date=July 5, 2002 |archive-url=https://web.archive.org/web/20020802145913/http://vitanuova.loyalty.org/2002-07-05.html |archive-date=August 2, 2002 |access-date=January 30, 2015 |url-status=unfit }}</ref><ref name="Flak">{{cite web\n|url=http://www.eetimes.com/document.asp?doc_id=1144938 |title=Microsoft scheme for PC security faces flak |last=Merritt |first=Rick |date=July 15, 2002 |access-date=January 30, 2015 |publisher=[[UBM plc]] |work=[[EE Times]]}}</ref><ref name="CopyrightDebate">{{cite news |url=http://archives.dailytimes.com.pk/infotech/09-Sep-2002/microsoft-allies-gear-to-reshape-copyright-debate |title=Microsoft, allies gear to reshape copyright debate |agency=Reuters |date=September 9, 2002 |newspaper=[[Daily Times (Pakistan)|Daily Times]] |access-date=September 1, 2015 |archive-date=March 4, 2016 |archive-url=https://web.archive.org/web/20160304055137/http://archives.dailytimes.com.pk/infotech/09-Sep-2002/microsoft-allies-gear-to-reshape-copyright-debate |url-status=dead }}</ref> Biddle enlisted assistance from members from the [[Microsoft Research]] division and other core contributors eventually included Blair Dillaway, [[Brian LaMacchia]], Bryan Willman, [[Butler Lampson]], John DeTreville, John Manferdelli, Marcus Peinado, and Paul England.<ref name="PdOverview">{{cite web |url=http://groups.csail.mit.edu/cis/crypto/classes/6.857/papers/lamacchia-palladium.ppt |title=An Overview of Palladium |last=LaMacchia |first=Brian |author-link=Brian LaMacchia |format=PPT |publisher=[[Microsoft]] |access-date=February 17, 2015}}</ref> Adam Barr, a former Microsoft employee who worked to secure the remote boot feature during development of [[Windows 2000]] was approached by Biddle and colleagues during his tenure with an initiative tentatively known as "Trusted Windows," which aimed to protect [[DVD]] content from being copied. To this end, Lampson proposed the use of a hypervisor to execute a limited operating system dedicated to DVD playback alongside Windows 2000.<ref name="Kuro5hin">{{cite web |url=http://www.kuro5hin.org/story/2002/7/9/17842/90350 |title=TCPA and Palladium: Sony Inside |date=July 9, 2002 |last=Barr |first=Adam  |publisher=[[Kuro5hin]] |access-date=January 30, 2015}}</ref> Patents for a DRM operating system were later filed in 1999 by DeTreville, England, and Lampson;<ref name="US6330670B1">{{Cite patent|US|6330670|title=Digital rights management operating system |status=patent |assign1=Microsoft Corporation|invent3=Lampson, Butler |invent2=DeTreville, John |invent1=England, Paul}}</ref><ref name="US6327652B1">{{Cite patent|US|6327652|title=Loading and identifying a digital rights management operating system  |status=patent |assign1=Microsoft Corporation|invent3=Lampson, Butler |invent2=DeTreville, John |invent1=England, Paul}}</ref> Lampson noted that these patents were for NGSCB.<ref name="CV">{{cite web |url=http://research.microsoft.com/en-us/um/people/blampson/cv.doc |title=Cirriculum Vitae |last=Lampson |first=Butler |author-link=Butler Lampson |publisher=[[Microsoft]] |format=DOC |access-date=January 30, 2015}}</ref> Biddle and colleagues realized by 1999 that NGSCB was more applicable to privacy and security than content protection, and the project was formally given the [[green-light]] by Microsoft in October, 2001.<ref name="TheBigSecret"/><ref name="Flak"/><ref name="CopyrightDebate"/><ref name="Manferdelli2002">{{cite web |url=http://news.microsoft.com/2002/07/01/qa-microsoft-seeks-industry-wide-collaboration-for-palladium-initiative/ |title=Q&A: Microsoft Seeks Industry-Wide Collaboration for Palladium Initiative |date=July 1, 2002 |publisher=[[Microsoft]] |work=News Center |access-date=January 30, 2015}}</ref>\n\nDuring WinHEC 1999, Biddle discussed intent to create a "trusted" architecture for Windows to leverage new hardware to promote confidence and security while preserving backward compatibility with previous software.<ref name="Nash">{{cite web |url=http://download.microsoft.com/download/c/f/1/cf1806ad-5a4f-4f7d-a5b2-07fdb59a7adb/WH03_TPT17.exe |title=Microsoft Directions In Security: Making It Real |archive-url=https://web.archive.org/web/20030808211422/http://download.microsoft.com/download/c/f/1/cf1806ad-5a4f-4f7d-a5b2-07fdb59a7adb/WH03_TPT17.exe |archive-date=August 8, 2003 |last=Nash |first=Mike |date=2003 |publisher=[[Microsoft]] |format=EXE |access-date=February 16, 2015}}</ref> On October 11, 1999, the [[Trusted Computing Group|Trusted Computing Platform Alliance]], a consortium of various technology companies including [[Compaq]], [[Hewlett-Packard]], [[IBM]], [[Intel]], and Microsoft was formed in an effort to promote personal computing confidence and security.<ref name="TCPA">{{cite web |url=https://www-03.ibm.com/press/us/en/pressrelease/2016.wss |title=Compaq, Hewlett Packard, IBM, Intel, and Microsoft Announce Open Alliance to Build Trust and Security into PCs for e-business |last=Gorman |first=Ray |date=October 11, 1999 |publisher=[[IBM]] |access-date=February 16, 2015}}</ref> The TCPA released detailed specifications for a trusted computing platform with focus on features such as code validation and encryption based on integrity measurements, hardware-based key storage, and machine authentication; these features required a new hardware component designed by the TCPA called the "Trusted Platform Module" (referred to as a "Security Support Component",<ref name="MS-NGSCB-FAQ"/> "Security CoProcessor",<ref name="NISTPalladium"/> or "Security Support Processor"<ref name="NISTPalladium"/> in early NGSCB documentation).\n\nAt WinHEC 2000, Microsoft released a technical presentation on the topics of protection of privacy, security, and [[intellectual property]] titled "Privacy, Security, and Content in Windows Platforms", which focused on turning Windows into a "platform of trust" for computer security, user content, and user privacy. Notable in the presentation is the contention that "there is no difference between privacy protection, computer security, and content protection"\u2014"assurances of trust must be universally true".<ref name="TrustedWindows"/> Microsoft reiterated these claims at WinHEC 2001.<ref name="WinHEC2001">{{cite web |url=http://download.microsoft.com/download/a/f/c/afcf8195-0eda-4190-a46d-aa60b45e0740/Secure.ppt |title=Privacy, Security, and Content Protection |last3=Flanagan |first3=Dennis |last2=Peinado |first2=Marcus |last1=Biddle |first1=Peter |date=2001 |publisher=[[Microsoft]] |format=PPT |access-date=January 30, 2015 |archive-date=June 26, 2017 |archive-url=https://web.archive.org/web/20170626001906/http://download.microsoft.com/download/a/f/c/afcf8195-0eda-4190-a46d-aa60b45e0740/Secure.ppt |url-status=dead }}</ref> NGSCB intended to protect all forms of content, unlike traditional rights management schemes which focus only on the protection of audio tracks or movies instead of users they have the potential to protect which made it, in Biddle's words, "egalitarian".<ref name="TrustedWindows"/><ref name="PEU">{{cite web |url=http://marc.info/?l=cypherpunks&m=102874057630774&w=2 |title=Re: Privacy-enabling uses for TCPA - MARC |last=Biddle |first=Peter |author-link=Peter Biddle |publisher=[[MARC (archive)|MARC]] |access-date=May 1, 2015}}</ref>\n\n Microsoft held its first design review for the NGSCB in April 2002, with approximately 37 companies under a [[non-disclosure agreement]].<ref name="Flak"/> NGSCB was publicly unveiled under its codename "Palladium" in a June 2002 article by [[Steven Levy]] for ''[[Newsweek]]'' that focused on its design, feature set, and origin.<ref name="Geek.com">{{cite web |url=http://www.geek.com/chips/palladium-microsofts-big-plan-for-the-pc-549258/ |title=Palladium: Microsoft's big plan for the PC |author=Geek.com |date=June 24, 2002 |publisher=[[Ziff Davis Media]] |work=[[Geek.com]] |access-date=January 30, 2015 |archive-date=March 29, 2019 |archive-url=https://web.archive.org/web/20190329235643/https://www.geek.com/chips/palladium-microsofts-big-plan-for-the-pc-549258/ |url-status=dead }}</ref><ref name="RevisitsRM">{{cite web |url=http://www.extremetech.com/extreme/51436-palladium-microsoft-revisits-digitalrights-management |title=Palladium: Microsoft Revisits Digital Rights Management |author=ExtremeTech |date=June 24, 2002 |access-date=January 30, 2015 |publisher=[[Ziff Davis Media]]|author-link=ExtremeTech}}</ref> Levy briefly described potential features: access control, authentication, authorization, DRM, encryption, as well as protection from [[E-mail spam|junk mail]] and [[malware]], with example policies being [[email]] accessible only to an intended recipient and [[Microsoft Word]] documents readable for only a week after their creation;<ref name="TheBigSecret"/> Microsoft later release a guide clarifying these assertions as being hyperbolic; namely, that NGSCB would not intrinsically enforce content protection, or protect against junk mail or malware. Instead, it would provide a platform on which developers could build new solutions that did not exist by isolating applications and store secrets for them.<ref name="MS-NGSCB-FAQ"/> Microsoft was not sure whether to "expose the feature in the [[Control Panel (Windows)|Control Panel]] or present it as a separate utility," but NGSCB would be an opt-in solution\u2014disabled by default.<ref name="Channel">{{cite web  |url=http://www.crn.com/news/security/18820863/channel-positive-about-microsoft-palladium-security-project.htm |title=Channel Positive About Microsoft Palladium Security Project |last=Rooney |first=Paula |date=June 25, 2002 |access-date=January 30, 2015 |publisher=[[The Channel Company]]}}</ref>\n\nMicrosoft PressPass later interviewed John Manferdelli, who restated and expanded on many of the key points discussed in the article by ''Newsweek''. Manferdelli described it as evolutionary platform for Windows in July, articulating how "'Palladium' will not require DRM, and DRM will not require 'Palladium'.<ref name="Manferdelli2002"/> Microsoft sought a group program manager in August to assist in leading the development of several Microsoft technologies including NGSCB.<ref name="Recruitment">{{cite web |url=https://www.theregister.co.uk/2002/08/13/ms_recruits_for_palladium_microkernel/ |title=MS recruits for Palladium microkernel and/or DRM platform |last=Lettice |first=John |date=August 13, 2002 |access-date=January 30, 2015 |publisher=Situation Publishing |work=[[The Register]]}}</ref> [[Paul Otellini]] announced Intel's support for NGSCB with a set of chipset, platform, and processor codenamed "[[Trusted Execution Technology|LaGrande]]" at [[Intel Developer Forum]] 2002,<ref name="IDF2002">{{cite web |url=http://www.intel.com/pressroom/archive/speeches/otellini20020909.htm |title=Paul Otellini Keynote -- IDF Fall 2002 |date=September 9, 2002 |publisher=[[Intel]] |access-date=February 16, 2015}}</ref><ref name="SecurityRenaissance">{{cite web |url=https://www.theregister.co.uk/2002/09/10/intels_new_chip_for_security1/ |title=Intel's new chip for security Renaissance |last=Greene |first=Thomas |date=September 10, 2002 |publisher=Situation Publishing |work=[[The Register]] |access-date=February 16, 2015}}</ref> which would provide an NGSCB hardware foundation and preserve backward compatibility with previous software.<ref name="LGNGSCB">{{cite web |url=http://www.intel.com/idf/us/fall2003/presentations/F03USSCMS16_OS.pdf |last2=Jones-Ferron |first2=Mike |last1=Girard |first1=Luke |title=LaGrande Technology & Safer Computing Overview |date=2003 |publisher=[[Intel]] |archive-url=https://web.archive.org/web/20031217145829/http://www.intel.com/idf/us/fall2003/presentations/F03USSCMS16_OS.pdf |archive-date=December 17, 2003 |access-date=March 6, 2015}}</ref>\n\n NGSCB was known as "Palladium" until January 24, 2003 when Microsoft announced it had been renamed as "Next-Generation Secure Computing Base." Project manager Mario Juarez stated this name was chosen to avoid legal action from an unnamed company which had acquired the rights to the "Palladium" name, as well as to reflect Microsoft's commitment to NGSCB in the upcoming decade. Juarez acknowledged the previous name was controversial, but denied it was changed by Microsoft to dodge criticism.<ref name="CNET-NGSCB">{{cite web |url=http://news.cnet.com/2100-1001-982127.html |title=What's in a name? Not Palladium |last=Lemos |first=Robert |date=January 24, 2003 |publisher=[[CBS Interactive]] |work=[[CNET]] |archive-url=https://web.archive.org/web/20110810003317/http://news.cnet.com/2100-1001-982127.html |archive-date=August 10, 2011 |access-date=March 29, 2019}}</ref>\n\nThe Trusted Computing Platform Alliance was superseded by the Trusted Computing Group in April 2003.<ref name="TCG">{{cite web |url=http://www.eetimes.com/document.asp?doc_id=1202119 |title=New group aims to secure PCs, PDAs, cell phones |last=Merritt |first=Rick |date=April 8, 2003 |publisher=[[UBM plc]] |work=[[EETimes]] |access-date=February 16, 2015}}</ref> A principal goal of the new consortium was to produce a TPM specification compatible with NGSCB; the previous specification, TPM 1.1 did not meet its requirements.<ref name="Flak"/><ref name="DangersTCPAPalladium">{{cite web |url=http://www.cl.cam.ac.uk/~rja14/biddle.txt |title=Re: Dangers of TCPA/Palladium |last=Biddle |first=Peter |author-link=Peter Biddle |date=August 5, 2002 |format=TXT |access-date=February 16, 2015}}</ref> TPM 1.2 was designed for compliance with NGSCB<ref name="PEE">{{cite web |url=http://download.microsoft.com/download/8/d/5/8d5ec8cf-3e09-49e0-95dd-0a6a3ded510f/NGSCB_Privacy_Enhancements.doc |title=Privacy-Enabling Enhancements in the Next-Generation Secure Computing Base |publisher=[[Microsoft]] |date=2003 |archive-url=https://web.archive.org/web/20051228130120/http://download.microsoft.com/download/8/d/5/8d5ec8cf-3e09-49e0-95dd-0a6a3ded510f/NGSCB_Privacy_Enhancements.doc |archive-date=December 28, 2005 |format=DOC |access-date=February 21, 2015 |url-status=dead }}</ref> and introduced many features for such platforms.<ref name="TPM1.2NGSCB">{{cite web |url=http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04053_WINHEC2004.ppt |title=TPM 1.2 Trusted Platform Module And Its Use In NGSCB |last2=Zeman |first2=Pavel |last1=Heil |first1=Stephen |date=2004 |archive-url=https://web.archive.org/web/20060827073150/http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04053_WINHEC2004.ppt |archive-date=August 27, 2006 |publisher=[[Microsoft]] |format=PPT |access-date=February 21, 2015}}</ref> The first TPM 1.2 specification, Revision 62 was released in 2003.<ref name="TPMMainSpecification">{{cite web |url=http://www.trustedcomputinggroup.org/resources/tpm_main_specification |title=Trusted Computing Group - TPM Main Specification |author=Trusted Computing Group |access-date=February 21, 2015|author-link=Trusted Computing Group }}</ref>\n\nBiddle emphasized in June 2003 that hardware vendors and software developers were vital to NGSCB.<ref name="ControlPCs">{{cite web |url=http://www.eweek.com/c/a/Security/Microsoft-to-Get-More-Control-of-the-PC |title=Microsoft to Get More Control of the PC? |last=Fisher |first=Dennis |date=May 5, 2003  |publisher=[[QuinStreet]] |work=[[eWeek]] |access-date=January 30, 2015}}</ref> Microsoft publicly demonstrated NGSCB for the first time at WinHEC 2003,<ref name="Pd2003-04"/><ref name="ShowsOff">{{cite web |url=http://news.cnet.com/Microsoft-shows-off-security-prototype/2100-1009_3-1000142.html |title=Microsoft shows off security prototype |last=Lemos |first=Robert |date=May 6, 2003 |publisher=[[CBS Interactive]] |work=[[CNET]] |access-date=January 30, 2015}}</ref><ref name="RMPd">{{cite web |url=http://redmondmag.com/articles/2003/05/06/palladium-on-display-at-winhec.aspx |title=Palladium on Display at WinHEC |last=Bekker |first=Scott |date=May 6, 2003 |publisher=1105 Media Inc. |work=Redmond Magazine |access-date=January 30, 2015}}</ref> where it protected data in [[random-access memory|memory]] from an attacker; prevented access to\u2014and alerted the user of\u2014an application that had been changed; and prevented a [[remote administration tool]] from capturing an [[instant messaging]] conversation.<ref name="MSRightsScheme">{{cite web |url=http://www.extremetech.com/extreme/54096-microsoft-demos-ngscb-rights-scheme |title=Microsoft Demos NGSCB Rights Scheme |last=Hachman |first=Mark |date=May 7, 2003 |publisher=[[Ziff Davis Media]] |work=[[ExtremeTech]] |access-date=January 30, 2015}}</ref><ref name="NGSCBEmulators">{{cite web |url=http://www.networkworld.com/article/2342054/lan-wan/microsoft-turns-to-emulators-for-security-demo.html |title=Microsoft turns to emulators for security demo |last=Evers |first=Joris |date=May 7, 2003 |publisher=[[International Data Group|IDG]] |work=[[Network World]] |access-date=January 30, 2015}}</ref> Despite Microsoft's desire to demonstrate NGSCB on hardware,<ref name="NGSCBDemo">{{cite web |url=http://www.computerworld.com/article/2580817/security0/microsoft-plans-palladium-demo-in-may.html |title=Microsoft plans Palladium demo in May |last=Evers |first=Joris |date=March 26, 2003 |publisher=[[International Data Group|IDG]] |work=[[Computer World]] |access-date=January 30, 2015}}</ref> [[emulator|software emulation]] was required for as few hardware components were available.<ref name="NGSCBEmulators"/> Biddle reiterated that NGSCB was a set of evolutionary enhancements to Windows, basing this assessment on preserved backward compatibility and employed concepts in use before its development, but said the capabilities and scenarios it would enable would be revolutionary.<ref name="WinHEC2003">{{cite web |url=http://www.microsoft.com/en-us/news/features/2003/may03/05-07ngscb.aspx |title=At WinHEC, Microsoft Discusses Details of Next-Generation Secure Computing Base |date=May 7, 2003 |access-date=January 30, 2015 |author=Microsoft|author-link=Microsoft }}</ref> Microsoft also revealed its multi-year roadmap for NGSCB,<ref name="MaryFoley">{{cite web |url=https://www.pcmag.com/article2/0,2817,1009420,00.asp |title=Microsoft To Do More Than Just Demo 'Palladium' |last=Foley |first=Jo Mary |author-link=Mary Jo Foley |date=April 8, 2003 |publisher=[[Ziff Davis Media]] |work=[[PC Magazine]] |access-date=January 30, 2015}}</ref> with the next major development milestone scheduled for the [[Professional Developers Conference]],<ref name="NGSCBEmulators"/><ref name="ReadiesKit">{{cite web |url=http://www.infoworld.com/article/2678133/security/microsoft-readies-kit-for-security-initiative.html |title=Microsoft readies kit for security initiative |last=Krill |first=Paul |date=June 19, 2003 |publisher=[[International Data Group|IDG]] |work=[[InfoWorld]] |access-date=January 30, 2015}}</ref> indicating that subsequent versions would ship concurrently with pre-release builds of Windows Vista; however, news reports suggested that NGSCB would not be integrated with Windows Vista when release, but it would instead be made available as separate software for the operating system.<ref name="KanellosMichael">{{cite web |url=http://news.cnet.com/Microsoft-A-separate-look-for-security/2100-1012_3-1000584.html |title=Microsoft: A separate look for security |last=Kanellos |first=Michael |date=May 8, 2003 |publisher=[[CBS Interactive]] |work=[[CNET]] |access-date=January 30, 2015}}</ref>\n\nMicrosoft also announced details related to adoption and deployment of NGSCB at WinHEC 2003, stating that it would create a new value proposition for customers without significantly increasing the cost of computers; NGSCB adoption during the year of its introductory release was not anticipated and immediate support for servers was not expected.<ref name="PdAdoption">{{cite web |url=http://www.infoworld.com/article/2678589/security/winhec--microsoft-expects-slow-adoption-for-ngscb.html |title=WinHEC: Microsoft expects slow adoption for NGSCB |last=Evers |first=Joris |date=May 8, 2003 |publisher=[[International Data Group|IDG]] |work=[[InfoWorld]] |access-date=January 30, 2015}}</ref><ref name="PdServers">{{cite web |url=http://www.infoworld.com/article/2678353/computer-hardware/winhec---palladium--for-servers-a-long-way-out.html |title=WinHEC: Palladium for servers a long way out |last=Evers |first=Joris. |date=May 9, 2003 |publisher=[[International Data Group|IDG]] |work=[[InfoWorld]] |access-date=January 30, 2015}}</ref> On the last day of the conference, Biddle said NGSCB needed to provide users with a way to differentiate between secured and unsecured windows\u2014that a secure window should be "noticeably different" to help protect users from [[spoofing attacks]];<ref name="KanellosMichael"/> [[Nvidia]] was the earliest to announce this feature.<ref name="TrustedGraphicsandNGSCB">{{cite web|url=http://download.microsoft.com/download/c/f/1/cf1806ad-5a4f-4f7d-a5b2-07fdb59a7adb/WH03_TPT11.exe |title=Trusted Graphics and NGSCB |last2=Kirk |first2=David |last1=Biddle |first1=Peter |date=2003 |publisher=[[Microsoft]] |archive-url=https://web.archive.org/web/20030808211422/http://download.microsoft.com/download/c/f/1/cf1806ad-5a4f-4f7d-a5b2-07fdb59a7adb/WH03_TPT11.exe |archive-date=August 8, 2003 |access-date=December 2, 2015 |url-status=unfit}}</ref> WinHEC 2003 represented an important development milestone for NGSCB. Microsoft dedicated several hours to presentations and released many technical whitepapers,<ref name="TrustedPlatformTechnologies">{{cite web |url=http://www.microsoft.com/winhec/trusted03.mspx |title=Trusted Platform Technologies |date=2003 |archive-url=https://web.archive.org/web/20030620102525/http://www.microsoft.com/winhec/trusted03.mspx |archive-date=June 20, 2003 |access-date=January 30, 2015 |author=Microsoft |work=Windows Hardware Engineering Conference|author-link=Microsoft }}</ref><ref name="3DUI">{{cite web |url=http://www.extremetech.com/computing/54124-microsofts-longhorn-3d-ui150-more-info-emerges |title=Microsoft's Longhorn 3D UI - More Info Emerges |date=May 9, 2003 |publisher=[[Ziff Davis Media]] |work=[[ExtremeTech]] |access-date=January 30, 2015}}</ref><ref name="GetTechnical">{{cite web |url=http://www.itworld.com/article/2805325/operating-systems/microsoft-to-get-technical-on-longhorn-and--palladium-.html |title=Microsoft to get technical on Longhorn and Palladium |last=Bennett |first=Amy |date=May 2, 2003 |publisher=[[International Data Group|IDG]] |work=[[ITWorld]] |access-date=January 30, 2015}}</ref> and companies including [[Atmel]],<ref name="BusinessWire">{{cite web |url=http://www.businesswire.com/news/home/20030507005219/en/Atmel-Microsoft-Demonstrate-Secure-USB-Keyboard-Prototype |title=Atmel and Microsoft Demonstrate New Secure USB Keyboard Prototype at WinHEC 2003 |author=Business Wire |date=May 7, 2003  |access-date=January 30, 2015|author-link=Business Wire }}</ref> [[Comodo Group]],<ref name="FujitsuWinHEC2003">{{cite web |url=http://www.fujitsu.com/us/about/resources/news/press-releases/2003/fcai-20030506-2.html |title=Fujitsu Components and Comodo Demonstrate the Future of Secure Input at WINHEC 2003 |last=Linden |first=Marielle |date=May 6, 2003 |publisher=[[Fujitsu]] |access-date=January 30, 2015}}</ref><ref name="SIDEN">{{cite web |url=https://www.comodo.com/products/pdf/SIDEN_Trust_Chip_Brochure.pdf |title=SIDEN TC4000 Cost Optimized Security Solution (NGSCB Compatible) |author=Comodo Group |date=2003 |access-date=November 22, 2014|author-link=Comodo Group }}</ref> [[Fujitsu]],<ref name="FujitsuWinHEC2003"/> and [[SafeNet]]<ref name="SafeNet">{{cite web |url=http://www.safenet-inc.com/news/2003/2003-05-06-safenet-supplies-encryption-technology-to-microsoft-for-its/ |title=SafeNet Supplies Encryption Technology to Microsoft for its Next-Generation Secure Computing Base Demonstration |date=May 6, 2003 |author=SafeNet |access-date=January 30, 2015|author-link=SafeNet }}</ref><ref name="SafeNetBusinessWire">{{cite web |url=http://www.businesswire.com/news/home/20030506005151/en/SafeNet-Supplies-Encryption-Technology-Microsoft-Next-Generation-Secure |title=SafeNet Supplies Encryption Technology to Microsoft for its Next-Generation Secure Computing Base Demonstration; SafeNet to Demonstrate New Technology at the WinHEC 2003 Conference |date=May 6, 2003 |publisher=[[BusinessWire]] |access-date=December 6, 2015}}</ref> produced preliminary hardware for the demonstration. Microsoft also demonstrated NGSCB at several U.S. campuses in California and in New York in June 2003.<ref name="ReadiesKit"/><ref name="OnTour">{{cite web |url=http://www.infoworld.com/article/2679001/security/microsoft-takes--palladium--on-tour.html |title=Microsoft takes 'Palladium' on tour |last=Evers |first=Joris |date=June 12, 2003 |publisher=[[International Data Group|IDG]] |work=[[InfoWorld]] |access-date=January 30, 2015}}</ref>\n\n[[File:NGSCBRoadmap.png|200px|thumb|right|Microsoft's roadmap for NGSCB as revealed during WinHEC 2003.]]\nNGSCB was among the topics discussed during Microsoft's PDC 2003 with a pre-beta [[software development kit]], known as the Developer Preview, being distributed to attendees.<ref name="Pd2003-04"/> The Developer Preview was the first time that Microsoft made NGSCB code available to the developer community and was offered by the company as an educational opportunity for NGSCB software development.<ref name="PdDP">{{cite web |url=http://www.networkworld.com/article/2338050/lan-wan/developers-get-hands-on-microsoft-s-ngscb.html |title=Developers get hands on Microsoft's NGSCB |last=Evers |first=Joris |date=October 30, 2003 |access-date=January 30, 2015 |publisher=[[International Data Group|IDG]] |work=[[NetworkWorld]]}}</ref> With this release, Microsoft stated that it was primarily focused on supporting business and enterprise applications and scenarios with the first version of the NGSCB scheduled to ship with Windows Vista, adding that it intended to address consumers with a subsequent version of the technology, but did not provide an estimated time of delivery for this version.<ref name="Overview and Drilldown"/><ref name="PdDP"/> At the conference, [[Jim Allchin]] said that Microsoft was continuing to work with hardware vendors so that they would be able to support the technology,<ref name="SpeechTranscript">{{cite web |url=http://news.microsoft.com/2003/10/27/speech-transcript-jim-allchin-microsoft-professional-developers-conference-2003/ |title=Speech Transcript \u2013 Jim Allchin, Microsoft Professional Developers Conference 2003 |date=October 27, 2003 |publisher=[[Microsoft]] |work=News Center |access-date=January 30, 2015}}</ref> and [[Bill Gates]] expected a new generation of [[central processing unit]]s to offer full support.<ref name="PdCPUtr">{{cite web |url=https://www.theregister.co.uk/2003/10/28/ngscb_aka_palladium_in_next1/ |title=NGSCB, aka Palladium, in next generation of CPU, says Gates |last=Lettice |first=John |date=October 28, 2003 |publisher=Situation Publishing |work=[[The Register]] |access-date=January 30, 2015}}</ref> Following PDC 2003, NGSCB was demonstrated again on prototype hardware during the annual [[RSA Security]] conference in November.<ref name="RSAConference">{{cite web |url=http://news.microsoft.com/2003/11/04/microsoft-details-new-security-innovations-at-rsa-conference-2003-europe/ |title=Microsoft Details New Security Innovations at RSA Conference 2003, Europe |date=November 4, 2003 |publisher=[[Microsoft]] |work=News Center |access-date=January 30, 2015}}</ref>\n\nMicrosoft announced at WinHEC 2004 that it would revise NSCB in response to feedback from customers and [[independent software vendor]]s who did not desire to rewrite their existing programs in order to benefit from its functionality;<ref name="RevisitsSecurity"/><ref name="ShakesUpSecurity">{{cite web | url=http://www.v3.co.uk/v3-uk/news/1979725/microsoft-shakes-longhorn-security | title=Microsoft shakes up Longhorn security |last=Sanders |first=Tom |date=May 6, 2004 |access-date=January 30, 2015 |publisher=[[Incisive Media]]}}</ref> the revision would also provide more direct support for Windows with protected environments for the operating system, its components, and applications, instead of it being an environent to itself and new applications.<ref name="PdWinHEC2004">{{cite web |url=http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04008_WINHEC2004.ppt |title=Next-Generation Secure Computing Base |last=Biddle |first=Peter |author-link=Peter Biddle |date=2004 |archive-url=https://web.archive.org/web/20060827073150/http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04008_WINHEC2004.ppt |archive-date=August 27, 2006 |format=PPT |access-date=January 30, 2015 |publisher=[[Microsoft]]}}</ref> The NGSCB secure input feature would also undergo a significant revision based on cost assessments, hardware requirements, and usability issues of the previous implementation.<ref name="WinHEC2004SecureInput">{{cite web |url=http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04055_WINHEC2004.ppt |title=Securing the User Input Path on NGSCB Systems |last=Wooten |first=David |date=2004 |archive-url=https://web.archive.org/web/20060509115312/http://download.microsoft.com/download/1/8/f/18f8cee2-0b64-41f2-893d-a6f2295b40c8/TW04055_WINHEC2004.ppt |archive-date=May 9, 2006 |publisher=[[Microsoft]] |format=PPT |access-date=September 12, 2015}}</ref> There were subsequent reports that Microsoft would cease developing NGSCB;<ref name="ArsNGSCB">{{cite web |url=https://arstechnica.com/uncategorized/2004/05/3736-2/  |title=Microsoft kills Next-Generation Secure Computing Base |last=Bangeman |first=Eric |date=May 5, 2004 |access-date=January 30, 2015 |publisher=[[Cond\u00e9 Nast]] |work=[[Ars Technica]]}}</ref><ref name="NGSCBvNX">{{cite web |url=http://www.crn.com/news/security/18841713/microsoft-shelves-ngscb-project-as-nx-moves-to-center-stage.htm |title=Microsoft shelves NGSCB project as NX moves to center stage |last=Rooney |first=Paula |date=May 5, 2004 |access-date=January 30, 2015 |publisher=[[The Channel Company]]}}</ref> Microsoft denied these reports and reaffirmed its commitment to delivery.<ref name="eWeekPd"/><ref name="WinHEC2004ShowReport">{{cite web |url=http://winsupersite.com/product-review/winhec-2004-show-report-and-photo-gallery |title=WinHEC 2004 Show Report and Photo Gallery |last=Thurrott |first=Paul |author-link=Paul Thurrott |date=May 7, 2004  |access-date=January 30, 2015 |publisher=[[Penton (professional information services)|Penton]] |work=Supersite for Windows}}</ref> Additional reports published later that year suggested that Microsoft would make even additional changes based on feedback from the industry.<ref name="Controversial"/><ref name="NGSCB2004-CW">{{cite web |url=http://www.computerworld.com/article/2566246/security0/what-to-expect-from-microsoft-s-ngscb-plan.html |title=What to expect from Microsoft's NGSCB plan |last=Liang |first=Ping |date=August 19, 2004 |publisher=[[International Data Group|IDG]] |work=[[ComputerWorld]] |access-date=June 26, 2015}}</ref>\n\nMicrosoft's absence of continual updates on NGSCB progress in 2005 had caused industry insiders to speculate that NGSCB had been cancelled.<ref name="SilenceAndSpeculation">{{cite web |url=http://www.pcworld.com/article/119798/article.html |title=Silence Fuels Speculation on Microsoft Security Plan |last=Evers |first=Joris |date=February 24, 2005 |publisher=[[International Data Group|IDG]] |work=[[PCWorld]] |access-date=January 30, 2015 |archive-date=June 13, 2015 |archive-url=https://web.archive.org/web/20150613214727/http://www.pcworld.com/article/119798/article.html |url-status=dead }}</ref> At the Microsoft Management Summit event, [[Steve Ballmer]] said that the company would build on the security foundation it had started with the NGSCB to create a new set of [[virtualization]] technologies for Windows,<ref name="MMS">{{cite web |url=http://www.microsoft.com/en-us/news/exec/steve/2005/04-20managementsummit.aspx |title=Steve Ballmer: Microsoft Management Summit |date=April 20, 2005 |access-date=January 30, 2015 |author=Microsoft|author-link=Microsoft }}</ref> which were later [[Hyper-V]]. Reports during WinHEC 2005 indicated Microsoft scaled back its plans for NGSCB, so that it could to ship Windows Vista\u2014which had already been beset by numerous delays and even a "development reset"\u2014within a reasonable timeframe; instead of isolating components, NGSCB would offer "Secure Startup" ("BitLocker Drive Encryption") to encrypt disk volumes and validate both pre-boot firmware and operating system components.<ref name="LonghornSecurity"/><ref name="Delays">{{cite web |url=http://www.computerworld.com/article/2555794/security0/microsoft-delays-bulk-of-next-generation-security-plan.html |title=Microsoft delays bulk of next-generation security plan |last=Evers |first=Joris |date=April 25, 2005 |publisher=[[International Data Group|IDG]] |work=[[ComputerWorld]] |access-date=June 26, 2015}}</ref><ref name="LR">{{cite web |url=http://www.securityfocus.com/news/11005 |title=Microsoft reveals hardware security plans, concerns remain |last=Lemos |first=Robert |date=April 26, 2005 |access-date=January 30, 2015 |publisher=[[NortonLifeLock|Symantec]] |work=[[SecurityFocus]]}}</ref><ref name="DustsOff">{{cite web |url=https://www.pcmag.com/article2/0,2817,1786570,00.asp |title=Microsoft Dusts Off 'Palladium' Security for Longhorn |last=Foley Jo |first=Mary |author-link=Mary Jo Foley |date=April 15, 2005 |publisher=[[Ziff Davis]] |work=[[PC Magazine]] |access-date=June 11, 2015}}</ref> Microsoft intended to deliver other aspects of NGSCB later.<ref name="MS-NGSCB"/> [[Jim Allchin]] stated NGSCB would "marry hardware and software to gain better security", which was instrumental in the development of BitLocker.<ref name="DustsOff"/>"}},
{"article_title": "Dial-up Internet access", "pageid": "59546", "revid": "1060515794", "timestamp": "2021-12-16T00:51:27Z", "history_paths": [["Dial-up Internet access --- Introduction ---", "History"]], "categories": ["american inventions", "internet access", "web 1.0", "obsolete technologies"], "heading_tree": {"Dial-up Internet access --- Introduction ---": {"History": {}, "Modems": {}, "Availability": {}, "Replacement by broadband": {}, "Performance": {"Using compression to exceed 56k": {"Compression by the ISP": {}}}, "Usage in other devices": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Dial-up Internet access --- Introduction ---|History": "In 1979, [[Tom Truscott]] and [[Jim Ellis (computing)|Jim Ellis]], graduates of [[Duke University]], created an early predecessor to dial-up Internet access called the [[USENET]]. The USENET was a [[UNIX]] based system that used a dial-up connection to transfer data through telephone modems.<ref name="Hauben">{{cite book|last1=Hauben|first1=Michael|last2=Hauben|first2=Rhonda|title=Netizens: On the History and Impact of Usenet and the Internet|date=1997|publisher=IEEE Computer Society Press|location=Los Alamitos, CA|isbn=0-8186-7706-6|pages=161\u2013200|edition=1st|url=http://www.columbia.edu/~rh120/|access-date=25 February 2017}}</ref> Dial-up Internet has been around since the 1980s via public providers such as [[NSFNET]]-linked universities. The [[BBC]] established Internet access via [[Brunel University]] in the United Kingdom in 1989.<ref>{{Cite web|url=https://support.bbc.co.uk/support/history.html|title=BBC Internet Services - History|website=support.bbc.co.uk|access-date=2019-09-19}}</ref> Dial-up was first offered commercially in 1992 by [[Pipex]] in the United Kingdom and [[Sprint Corporation|Sprint]] in the United States.<ref>{{Cite news|url=https://www.telegraph.co.uk/technology/connecting-britain/timeline-how-uk-got-connected/|title=How the UK got connected|date=2016-10-27|work=The Telegraph|access-date=2019-09-17|language=en-GB|issn=0307-1235|postscript=none}}; {{cite web|url=http://www.gtnet.gov.uk/corporate/about/|title=About PIPEX|publisher=GTNet|access-date=2012-06-30|archive-url=https://web.archive.org/web/20121101022035/http://www.gtnet.gov.uk/corporate/about/|archive-date=2012-11-01|url-status=dead}}</ref><ref>{{cite web |url=http://h-net.msu.edu/cgi-bin/logbrowse.pl?trx=vx&list=edtech&month=9207&week=&msg=An61j4s0%2BR1UHNuEZOgGfw&user=&pw= |website=h-net.msu.edu |date=31 July 1992 |title=H-Net Discussion Networks \u2013 SprintLink Commercial Availability Announced (fwd) |access-date=16 October 2015 |archive-url=https://web.archive.org/web/20160305153637/http://h-net.msu.edu/cgi-bin/logbrowse.pl?trx=vx&list=edtech&month=9207&week=&msg=An61j4s0%2BR1UHNuEZOgGfw&user=&pw= |archive-date=5 March 2016 |url-status=dead }}</ref> After the introduction of commercial [[broadband]] in the late 1990s,<ref>{{Cite web|url=http://home.bt.com/tech-gadgets/internet/broadband/who-invented-broadband-11364284589900|title=Who invented broadband? How copper telephone lines became high-speed internet connections|date=25 July 2018|website=BT|access-date=19 September 2019}}</ref> dial-up Internet access became less popular in the mid-2000s. It is still used where other forms are not available or where the cost is too high, as in some rural or remote areas.<ref>{{Cite news|url=https://www.digitaltrends.com/cool-tech/aol-dial-up-a-relic-of-the-past/|title=What's it like to use AOL dial-up internet in 2017?|date=2017-04-01|work=Digital Trends|access-date=2018-06-03|language=en-US}}</ref><ref>{{Cite news|url=http://www.cbc.ca/news/technology/dial-up-internet-used-by-hundreds-of-thousands-in-canada-1.1202392|title=Dial-up internet used by hundreds of thousands in Canada {{!}} CBC News|work=CBC|access-date=2018-06-03|language=en-US}}</ref>"}},
{"article_title": "Anti-lock braking system", "pageid": "59587", "revid": "1062404128", "timestamp": "2021-12-28T07:32:52Z", "history_paths": [["Anti-lock braking system --- Introduction ---", "History"]], "categories": ["vehicle safety technologies", "mechanical power control", "motorcycle technology", "vehicle braking technologies"], "heading_tree": {"Anti-lock braking system --- Introduction ---": {"History": {"Early systems": {}, "Modern systems": {}}, "Operation": {}, "Components": {}, "Use": {}, "Brake types": {}, "Effectiveness": {}, "ABS on motorcycles": {"History of motorcycle ABS": {}, "Basic principle": {}, "Anti-lock Braking System (ABS)": {}, "Combined Braking System (CBS)": {}, "CBS and ABS": {}}, "Safety and legislation": {"Safety": {}, "Laws and regulations": {}}, "See also": {}, "Further reading": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Anti-lock braking system --- Introduction ---|History": "The concept for ABS predates the modern systems that were introduced in the 1950s. In 1908, for example, J.E. Francis introduced his 'Slip Prevention Regulator for Rail Vehicles'.<ref name="Lawes2014">{{cite book|author=Jon Lawes|title=Car Brakes: A Guide to Upgrading, Repair and Maintenance|url=https://books.google.com/books?id=Sod8AwAAQBAJ&pg=PT207|date=31 January 2014|publisher=Crowood|isbn=978-1-84797-675-8|pages=207\u2013}}</ref>\n\nIn 1920 the French [[automobile]] and aircraft pioneer [[Gabriel Voisin]] experimented with systems that modulated the hydraulic braking pressure on his aircraft brakes to reduce the risk of tire slippage, as threshold braking on aircraft is nearly impossible. These systems used a [[flywheel]] and valve attached to a hydraulic line that feeds the brake cylinders. The flywheel is attached to a drum that runs at the same speed as the wheel. In normal braking, the drum and flywheel should spin at the same speed. However, when a wheel slows down, then the drum would do the same, leaving the flywheel spinning at a faster rate. This causes the valve to open, allowing a small amount of brake fluid to bypass the master cylinder into a local reservoir, lowering the pressure on the cylinder and releasing the brakes. The use of the drum and flywheel meant the valve only opened when the wheel was turning. In testing, a 30% improvement in braking performance was noted, because the pilots immediately applied full brakes instead of slowly increasing pressure in order to find the skid point. An additional benefit was the elimination of burned or burst tires.<ref>{{cite web |url=http://www.flightglobal.com/pdfarchive/view/1953/1953%20-%201433.html |title=Non-Skid Braking |work=Flight International |date=30 October 1953 |pages=587\u2013588}}</ref>\n\nThe first proper recognition of the ABS system came later with the German engineer Karl Waessel, whose system for modulating braking power was officially patented in 1928. Wessel, however, never developed a working product and neither did [[Robert Bosch]] who produced a similar patent eight years later.<ref name="Lawes2014"/>\n\nBy the early 1950s, the [[Maxaret|Dunlop Maxaret]] anti-skid system was in widespread aviation use in the UK, with aircraft such as the [[Avro Vulcan]] and [[Handley Page Victor]], [[Vickers Viscount]], [[Vickers Valiant]], [[English Electric Lightning]], [[de Havilland Comet|de Havilland Comet 2c]], [[de Havilland Sea Vixen]], and later aircraft, such as the [[Vickers VC10]], [[Hawker Siddeley Trident]], [[British Aerospace 125|Hawker Siddeley 125]], [[Hawker Siddeley HS 748]] and derived [[British Aerospace ATP]], and [[BAC One-Eleven]], and the Dutch [[Fokker F27 Friendship]] (which unusually had a Dunlop high pressure (200 Bar) pneumatic system in lieu of hydraulics for braking, nose wheel steering and landing gear retraction), being fitted with Maxaret as standard.<ref>{{cite web|url=http://www.flightglobal.com/pdfarchive/search.aspx?ArchiveSearchForm%24search=maxaret&ArchiveSearchForm%24fromYear=&ArchiveSearchForm%24toYear=&x=0&y=0 |title=Browse Flight's archive of Historic Aviation |publisher=Flightglobal.com |access-date=2014-08-26}}</ref> Maxaret, while reducing braking distances by up to 30% in icy or wet conditions, also increased tire life, and had the additional advantage of allowing take-offs and landings in conditions that would preclude flying at all in non-Maxaret equipped aircraft.\n\nIn 1958, a [[Royal Enfield Super Meteor]] [[motorcycle]] was used by the [[Transport Research Laboratory|Road Research Laboratory]] to test the Maxaret anti-lock brake.<ref name="Reynolds">{{cite book|last=Reynolds|first=Jim|title=Best of British Bikes|publisher=Patrick Stephens Ltd|year=1990|isbn=1-85260-033-0|url-access=registration|url=https://archive.org/details/bestofbritishbik0000reyn}}</ref> The experiments demonstrated that anti-lock brakes can be of great value to motorcycles, for which skidding is involved in a high proportion of accidents. Stopping distances were reduced in most of the tests compared with locked wheel braking, particularly on slippery surfaces, in which the improvement could be as much as 30 percent. Enfield's technical director at the time, Tony Wilson-Jones, saw little future in the system, however, and it was not put into production by the company.<ref name="Reynolds"/>\n\nA fully-mechanical system saw limited automobile use in the 1960s in the [[Ferguson P99]] racing car, the [[Jensen FF]], and the experimental [[all wheel drive]] [[Ford Zodiac]], but saw no further use; the system proved expensive and unreliable.\n\nThe first fully-electronic anti-lock braking system was developed in the late-1960s for the [[Concorde]] aircraft.\n\nThe modern ABS system was invented in 1971 by Mario Palazzetti (known as 'Mister ABS') in the Fiat Research Center and is now standard in almost every car. The system was called Antiskid and the patent was sold to Bosch who named it ABS.<ref name="google.com">Google Patents: [https://patents.google.com/patent/US3707313 US3707313A - Anti-skid braking systems - Google Patents], accessdate: 16. July 2020</ref>\n\n [[File:Martin Motors CEO Rear.JPG|thumb|A car with a sticker in the rear conveying about having ABS and EBD features.]]\n[[Chrysler]], together with the [[Bendix Corporation]], introduced a computerized, three-channel, four-sensor all-wheel<ref>{{cite web|url=http://www.oldcarbrochures.com/static/NA/Chrysler_and_Imperial/1972%20Chrysler/1972_Imperial_Press_Kit/1972%20Imperial%20Press%20Kit-04.html |title=Directory Index: Chrysler_and_Imperial/1972 Chrysler/1972_Imperial_Press_Kit |publisher=Oldcarbrochures.com |access-date=2014-08-26}}</ref> ABS called "Sure Brake" for its 1971 [[Imperial (automobile)|Imperial]].<ref>{{cite web |url=http://imperialclub.org/~imperialclub/Yr/1973/Data/49.htm |title=Chrysler Imperial Sure Brake system description |publisher=ImperialClub.org |access-date=2008-11-11 |archive-url=https://web.archive.org/web/20110726174127/http://imperialclub.org/~imperialclub/Yr/1973/Data/49.htm |archive-date=2011-07-26 |url-status=dead }}</ref> It was available for several years thereafter, functioned as intended, and proved reliable. In 1969 1/2, Ford introduced an anti-lock braking system called "Sure-Track" to the rear wheels of the [[Lincoln Continental Mark III]] and [[Ford Thunderbird]], as an option;<ref>{{cite web|url=http://www.oldcarbrochures.com/static/NA/Lincoln/1970_Lincoln/1970%20Lincoln%20Continental%20Brochure/1970%20Lincoln%20Continental-15.html |title=Directory Index: Lincoln/1970_Lincoln/1970 Lincoln Continental Brochure |publisher=Oldcarbrochures.com |access-date=2014-08-26}}</ref> it became standard in 1971.<ref>{{cite web|url=http://www.oldcarbrochures.com/static/NA/Lincoln/1971_Lincoln/1971_Lincoln_Continental_Brochure/1971%20Lincoln%20Continental-13.html |title=Directory Index: Lincoln/1971_Lincoln/1971_Lincoln_Continental_Brochure |publisher=Oldcarbrochures.com |access-date=2014-08-26}}</ref>  The Sure-Track braking system was designed with help from Kelsey-Hayes.  In 1971, [[General Motors]] introduced the "Trackmaster" rear-wheel only<ref>{{cite web|url=http://www.oldcarbrochures.com/static/NA/Cadillac/1972_Cadillac/1972_Cadillac_Brochure_1/1972%20Cadillac-25.html |title=Directory Index: Cadillac/1972_Cadillac/1972_Cadillac_Brochure_1 |publisher=Oldcarbrochures.com |access-date=2014-08-26}}</ref> ABS as an option on their [[rear-wheel drive]] [[Cadillac]] models<ref>{{cite web |url=http://www.welovecadillacs.com/history.html |archive-url=https://web.archive.org/web/20040603095607/http://welovecadillacs.com/history.html |url-status=dead |archive-date=2004-06-03 |title=History |publisher=We Love Cadillacs }}</ref><ref>{{cite web|url=http://history.gmheritagecenter.com/wiki/index.php/1972,_First_Automotive_Anti-lock_Brake_System_(ABS)|title=1972, First Automotive Anti-lock Brake System (ABS)|work=gmheritagecenter.com|access-date=2011-03-17|archive-url=https://web.archive.org/web/20131203054131/http://history.gmheritagecenter.com/wiki/index.php/1972,_First_Automotive_Anti-lock_Brake_System_(ABS)|archive-date=2013-12-03|url-status=dead}}</ref> and the [[Oldsmobile Toronado]].<ref>{{cite web|url=http://www.oldcarbrochures.com/static/NA/Oldsmobile/1971%20Oldsmobile/album/1971%20Oldsmobile%20Toronado-06.html |title=Directory Index: Oldsmobile/1971 Oldsmobile/album |publisher=Oldcarbrochures.com |access-date=2014-08-26}}</ref> In the same year, [[Nissan]] offered an EAL (Electro Anti-lock System) developed by Japanese company [[Denso]] as an option on the [[Nissan President]], which became [[Japan]]'s first electronic ABS.<ref>{{cite web |url=http://www.jsae.or.jp/autotech/data_e/5-4e.html |title=Electro antilock system (installed in Nissan President) |work=240 Landmarks of Japanese Automotive Technology |publisher=Society of Automotive Engineers in Japan, Inc. |access-date=2018-12-03 |archive-url=https://web.archive.org/web/20100720035152/http://www.jsae.or.jp/autotech/data_e/5-4e.html |archive-date=2010-07-20 |url-status=dead }}</ref>\n\n1971: [http://www.imperialclub.com/Yr/1971/SureBrake/ Imperial] {{Webarchive|url=https://web.archive.org/web/20200204105619/http://www.imperialclub.com/Yr/1971/SureBrake/ |date=2020-02-04 }} became the first production car with a 4 wheel computer-operated anti-lock braking system. Toyota introduced electronically controlled anti-skid brakes on [[Toyota Crown]].<ref>{{cite web|url=http://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/chassis/index.html|title=TOYOTA MOTOR CORPORATION GLOBAL WEBSITE - 75 Years of TOYOTA - Technical Development - Chassis|work=toyota-global.com}}</ref>\nIn 1972, four-wheel-drive [[Triumph 2000|Triumph 2500]] Estates were fitted with [[Mullard]] electronic systems as standard.{{cn|date=December 2021}} Such cars were very rare however and very few survive today.\n\n1971: First truck application: "Antislittamento" system developed by [[Fiat]] Veicoli Industriali and installed on [[Fiat]] truck model 691N1.<ref>{{cite web|url=https://www.youtube.com/watch?v=JbpmalG8VUE |archive-url=https://ghostarchive.org/varchive/youtube/20211211/JbpmalG8VUE| archive-date=2021-12-11 |url-status=live|title=Sistema antislittamento Sicurezza frenata - Centro Storico FIAT - Archivio Nazionale del Cinema d'Impresa, 1971|website=[[YouTube]]}}{{cbignore}}</ref>\n\n1976: [[Westinghouse Air Brake Company|WABCO]] began the development of the anti-locking braking system on commercial vehicles to prevent locking on slippery roads, followed in 1986 by the electronic braking system (EBS) for heavy-duty vehicles.<ref>{{cite web|url=http://www.wabco-auto.com/about-us/wabco-at-a-glance/our-history/|title=WABCO GLOBAL WEBSITE - 150 Years of WABCO|access-date=2017-01-02|archive-url=https://web.archive.org/web/20170122210817/http://www.wabco-auto.com/about-us/wabco-at-a-glance/our-history/|archive-date=2017-01-22|url-status=dead}}</ref>\n\n1978: [[Mercedes-Benz W116]] As one of the firsts, used an electronic four-wheel multi-channel anti-lock braking system (ABS) from [[Robert Bosch GmbH|Bosch]] as an option from 1978 on.\n\n1982: Honda introduced electronically controlled multi-channel ALB (Anti Locking Brakes) as an option for the second generation of Prelude, launched worldwide in 1982. \nAdditional info:\nThe general agent for Honda in Norway required all Preludes for the Norwegian market to have the ALB-system as a standard feature, making Honda Prelude be the first car delivered in Europe with ABS as a standard feature. The Norwegian general agent also included a sunroof and other options to be standard equipment in Norway, adding more luxury to the Honda brand. However, the Norwegian tax system made the well-equipped car very expensive, and the sales suffered from high costs. From 1984 the ALB-system, as well as the other optional features from Honda, was no longer a standard feature in Norway.\n\nIn 1985 the [[Ford Scorpio]] was introduced to the European market with a Teves electronic system throughout the range as standard. For this the model was awarded the coveted [[European Car of the Year]] Award in 1986, with very favorable praise from motoring journalists. After this success, Ford began research into Anti-Lock systems for the rest of their range, which encouraged other manufacturers to follow suit.\n\nSince 1987 ABS has been standard equipment on all [[Mercedes-Benz]] automobiles.<ref>{{cite web |title=Mercedes-Benz and the invention of the anti-lock braking system |url=https://media.daimler.com/marsMediaSite/en/instance/ko/Mercedes-Benz-and-the-invention-of-the-anti-lock-braking-system-ABS-ready-for-production-in-1978.xhtml?oid=9913502 |website=Daimler |publisher=Mercedes-Benz}}</ref>  [[Lincoln Motor Company|Lincoln]] followed suit in 1993.<ref>{{cite web|url=https://www.youtube.com/watch?v=wMJSXyTnOhI|title=1993 Lincoln safety ad|last=Anthony Slanda|date=15 July 2007|via=YouTube}}</ref>\n\nIn 1988, [[BMW]] introduced the first [[motorcycle]] with an [[Electrohydraulic servo valve|electro-hydraulic]] ABS: the [[BMW K100]]. [[Yamaha]] Introduced the FJ1200 model with optional ABS in 1991. [[Honda]] followed suit in 1992 with the launch of its first motorcycle ABS on the [[ST1100]] Pan European. In 2007, [[Suzuki]] launched its [[Suzuki Bandit Series|GSF1200SA (Bandit)]] with an ABS. In 2005, Harley-Davidson began offering an ABS option on police bikes."}},
{"article_title": "Disc brake", "pageid": "59597", "revid": "1059993466", "timestamp": "2021-12-12T21:51:25Z", "history_paths": [["Disc brake --- Introduction ---", "History"]], "categories": ["brakes", "vehicle braking technologies", "english inventions", "railway brakes"], "heading_tree": {"Disc brake --- Introduction ---": {"Design": {}, "History": {"Early experiments": {}, "First impact in racing": {}, "Mass production": {}, "In the U.S.": {}, "Motorcycles": {}}, "Brake disc": {"Motorcycles and scooters": {}, "Bicycles": {}, "Heavy vehicles": {}, "Rail and aircraft": {}, "Automotive use": {}, "Racing": {}, "Ceramic composites": {}, "Adjustment mechanism": {}, "Disc damage modes": {}, "Run-out": {}, "Scarring": {}, "Cracking": {}, "Rusting": {}}, "Calipers": {"Pistons and cylinders": {}}, "Brake pads": {}, "Common problems": {"Squeal": {}, "Judder or shimmy": {}, "Dust": {}, "Brake fade": {}}, "Patents": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Disc brake --- Introduction ---|History": "Development of disc brakes began in England in the 1890s.\n\nThe first caliper-type automobile disc brake was patented by [[Frederick William Lanchester]] in his Birmingham factory in 1902 and used successfully on [[Lanchester Motor Company|Lanchester cars]]. However, the limited choice of metals in this period meant that he had to use copper as the braking medium acting on the disc. The poor state of the roads at this time, no more than dusty, rough tracks, meant that the copper wore quickly making the system impractical.<ref name="hemmings1"/><ref name="Industrial">{{cite web|last=Bell |first=Andy |title=A brief history of the bicycle disc brake|date=May 2020 |url= https://industrialdesigncatalyst.com/2020/05/09/a-brief-history-of-the-bicycle-disc-brake/|access-date=20 August 2020}}</ref>\n\nIn 1921, the [[Douglas (motorcycles)|Douglas]] motorcycle company introduced a form of disc brake on the front wheel of their overhead-valve sports models. Patented by the British Motorcycle & Cycle-Car Research Association, Douglas described the device as a "novel wedge brake" working on a "bevelled hub flange", the brake was operated by a [[Bowden cable]]. Front and rear brakes of this type were fitted to the machine on which [[Tom Sheard]] rode to victory in the 1923 [[Senior TT]].<ref>{{cite journal |date=26 September 1957|title=The Editor's Correspondence - Vintage Disc Brakes|journal=Motor Cycling|publisher=Temple Press Ltd|location=London|pages=669}}</ref>\n\nSuccessful application began on railroad [[streamliner]] passenger trains and in airplanes and tanks before and during World War II. In the US, the [[Budd Company]] introduced disc brakes on the [[General Pershing Zephyr]] for the [[Chicago, Burlington & Quincy|Burlington Railroad]] in 1938. By the early 1950s, disc brakes were being regularly applied to new passenger rolling stock.<ref>D.P. Morgan, "All About the RDC," ''[[Trains (magazine)|Trains & Travel]]'' magazine, March 1953</ref> In Britain, the [[Daimler Company]] used disc brakes on its [[Daimler Armoured Car]] of 1939, the disc brakes, made by the [[Lucas Industries#Girling|Girling]] company, were necessary because in that [[four-wheel drive]] (4x4) vehicle the [[Epicyclic gearing|epicyclic]] [[final drive]] was in the wheel hubs and therefore left no room for conventional hub-mounted [[drum brake]]s.<ref>http://daimler-fighting-vehicles.co.uk/DFV-File%20Part%20Af%20-%20DAC%20Design%20&%20Development.pdf</ref>\n\nAt Germany's [[Argus Motoren]], Hermann Klaue (1912-2001) had patented<ref>{{cite web| url = https://www.google.gg/patents/US2323052| title = US2323052A - Disk brake for use in motor cars, airplanes, and the like - Google Patents}} Disk brake for use in motor cars, airplanes, and the like US 2323052 A</ref> disc brakes in 1940. Argus supplied wheels fitted with disc brakes e.g. for the [[Arado Ar 96]].<ref>{{cite web|url=http://www.lexikon-der-wehrmacht.de/Waffen/Ar96.htm|title=Lexikon der Wehrmacht - Ar 96|website=www.lexikon-der-wehrmacht.de|access-date=15 April 2018}}</ref> The German [[Tiger I]] heavy tank, was introduced in 1942 with a 55 cm Argus-Werke disc<ref>{{cite web|url=http://www.alanhamby.com/transmission.shtml|title=Tiger I Information Center - Transmission and Steering|website=www.alanhamby.com|access-date=15 April 2018}}</ref> on each drive shaft.\n\nThe American [[Crosley]] Hot Shot had four wheel disc brakes in 1949 and 1950, but these quickly proved troublesome and were removed.<ref name="hemmings1"/> Crosley returned to drum brakes, and drum brake conversions for Hot Shots were quite popular.<ref name="Langworth 1996"/> Lack of sufficient research caused reliability problems, such as sticking and corrosion, especially in regions using salt on winter roads.<ref name="Langworth 1996"/> Crosley four wheel Disc Brakes made Crosleys and Crosley based specials popular in SCCA H-Production and H-modified racing in the 1950s. {{citation needed|date=August 2021}} Their superior braking, made them difficult to beat. {{citation needed|date=August 2021}} The Crosley disc was a [[Goodyear Tire and Rubber Company|Goodyear]]-Hawley design, a modern caliper "spot" type with modern disc, derived from a design from aircraft applications.<ref name="hemmings1"/>\n\nCrosleys were not mere novelties, despite being sold from department stores.{{citation needed|date=August 2021}} The 1948 Crosley station wagon was the best selling station wagon in the world.{{citation needed|date=August 2021}}\n\n[[Chrysler]] developed a unique braking system, offered from 1949 to 1953.<ref name="ChryslerDisc">{{cite web|url=https://www.curbsideclassic.com/blog/1950-chrysler-crown-imperial-four-wheel-disc-brakes-standard-but-not-like-modern-discs/|title=1950 Chrysler Crown Imperial: Four Wheel Disc Brakes Standard \u2013 But Not Like Modern Discs|last=NIEDERMEYER|first=Paul|date=24 September 2015|access-date=20 August 2020}}</ref> Instead of the disc with caliper squeezing on it, this system used twin expanding discs that rubbed against the inner surface of a cast-iron brake drum, which doubled as the brake housing.<ref name="Langworth 1996">{{cite book |last=Langworth |first=Richard M. |title=Chrysler and Imperial: The Postwar Years |publisher=Motorbooks International |year=1994 |isbn=0-87938-034-9}}</ref> The discs spread apart to create friction against the inner drum surface through the action of standard [[wheel cylinder]]s.<ref name="Langworth 1996"/> Because of the expense, the brakes were only standard on the Chrysler Crown and the [[Chrysler Town & Country (1941\u20131988)|Town and Country Newport]] in 1950.<ref name="Langworth 1996"/> They were optional, however, on other Chryslers, priced around $400, at a time when an entire Crosley Hot Shot retailed for $935.<ref name="Langworth 1996"/> This four-wheel disc brake system was built by Auto Specialties Manufacturing Company (Ausco) of [[St. Joseph, Michigan]], under patents of inventor H.L. Lambert, and was first tested on a 1939 [[Plymouth (automobile)|Plymouth]].<ref name="Langworth 1996"/> Chrysler discs were "self energizing," in that some of the braking energy itself contributed to the braking effort.<ref name="Langworth 1996"/> This was accomplished by small balls set into oval holes leading to the brake surface.<ref name="Langworth 1996"/> When the disc made initial contact with the friction surface, the balls would be forced up the holes forcing the discs further apart and augmenting the braking energy.<ref name="Langworth 1996"/> This made for lighter braking pressure than with calipers, avoided brake fade, promoted cooler running, and provided one-third more friction surface than standard Chrysler twelve-inch drums.<ref name="Langworth 1996"/> Today's owners consider the [[Ausco Lambert disc brake|Ausco-Lambert]] very reliable and powerful, but admit its grabbiness and sensitivity.<ref name="Langworth 1996"/>\n\nIn 1953, 50 aluminum bodied [[Austin-Healey 100#100S|Austin-Healey 100S (Sebring)]] models, built primarily for racing, were the first European cars sold to the public to have disc brakes, fitted to all 4 wheels.<ref>{{cite book |last=Lawrence |first=Mike |title=A to Z of Sports Cars 1945\u20131990 |publisher=Bay View Books |year=1991 |isbn=978-1-870979-81-8 }}</ref>\n\n {{multiple image\n| align     = right\n| direction = vertical\n| image1    = Jaguar C TYPE dutch licence registration AE-19-27 pic08.jpg\n| caption1  = Jaguar C TYPE similar to 1953 "24 Heures du Mans" winner\n| image2    = Citroen DS 19 (c.late 1950s) (16575063556).jpg \n| caption2  = Citro\u00ebn DS 19 \n}}\nThe [[Jaguar C-Type]] racing car won the [[1953 24 Hours of Le Mans]], the only vehicle in the race to use disc brakes, developed in the [[United Kingdom|UK]] by [[Dunlop Rubber|Dunlop]], and the first car at Le Mans ever to average over 100 mph.<ref>{{cite web|url=https://www.stratstone.com/jaguar/e-type/why-le-mans-matters-to-jaguar/|title=Why Le Mans Matters to Jaguar|access-date=20 August 2021}}</ref> ''"Rivals\u2019 large drum brakes could match discs\u2019 ultimate stopping, but not their formidable staying power."'' <ref name="GiganticLeap">{{cite journal|url=https://www.motorsportmagazine.com/articles/sports-cars/le-mans/le-mans-1953-jaguars-gigantic-leap|first=Paul |last=Fearnley |title=Le Mans 1953: Jaguar's gigantic leap - History, Le Mans |publisher=Motor Sport Magazine |date=13 June 2013 |access-date=14 December 2015}}</ref>\n\nBefore this, in 1950, a Crosley HotShot with stock four wheel disc brakes won the Index of Performance in the first race at Sebring (6 hours rather than 12) on New Year's Eve in 1950. {{citation needed|date=August 2021}}  Crosley four wheel Disc Brakes made Crosleys and Crosley based specials popular in SCCA H-Production and H-modified racing in the 1950s. {{citation needed|date=August 2021}} Their superior braking, made them difficult to beat. {{citation needed|date=August 2021}}\n\n The [[Citro\u00ebn DS]] was the first sustained [[mass production]] use of modern automotive disc brakes, in 1955.<ref name="hemmings1"/><ref name="Industrial"/><ref name="MotorTrend2006">{{cite journal|publisher=[[Motor Trend]]|url=https://www.motortrend.com/vehicle-genres/c12-0511-1960-citroen-ds/|last=Bramley|first=Mark|title=Drive: 1960 Citroen DS Future Shock: Nothing as otherworldly radical had ever touched down on Planet Earth|date=11 August 2006|access-date=20 August 2020}}</ref><ref>{{cite web|title=Automotive Heroes \u2013 the Citro\u00ebn DS|last=Skelton|first=Sam|publisher=[[Classic & Sports Car]]|url=https://www.classicandsportscar.com/sponsored/promoted-automotive-heroes-citroen-ds|date= 21 August 2019|access-date=20 August 2020}}</ref><ref name="SMMT">{{cite web|title= Car safety \u2013 a brief history |date=3 February 2015 |publisher=The Society of Motor Manufacturers and Traders 71 Great Peter Street London SW1P 2BN|url=https://www.smmt.co.uk/2015/02/car-safety-brief-history/|access-date=20 August 2020}}</ref> The car featured caliper-type front disc brakes among its many innovations.<ref name="hemmings1"/> These discs were mounted inboard near the transmission, and were powered by the vehicle's central hydraulic system.  This model went on to sell 1.5 million units over 20 years with the same brake setup.<ref name="hemmings1"/>\n\nDespite early experiments in 1902, from British [[Lanchester Motor Company]], and in 1949 from Americans [[Chrysler]] and [[Crosley]], the costly, trouble prone technology wasn't ready for mass production.<ref name="hemmings1"/><ref name="ChryslerDisc"/> Attempts were soon withdrawn.<ref name="hemmings1"/><ref name="ChryslerDisc"/><ref name="Langworth 1996"/>\n\nThe [[Jensen 541]], with four-wheel disc brakes, followed in 1956.<ref name="hemmings1"/><ref>{{cite book |publisher=The Motor |title=October 17 |year=1956 }}</ref> Triumph exhibited a 1956 [[Triumph TR3|TR3]]  with disc brakes to the public, but the first production cars with Girling front-disc brakes were made in September 1956.<ref>{{cite journal|last=Lentinello |first=Richard |title=The first car with disc brakes really was . . . |journal=Hemmings Sports & Exotic Car |date=April 2011 |url= https://www.hemmings.com/magazine/hsx/2011/04/The-first-car-with-disc-brakes-really-was------/3698201.html |access-date=5 May 2018}}</ref>\n\nDisc brakes were most popular on [[sports car]]s when they were first introduced, since these vehicles are more demanding about brake performance. Discs have now become the more common form in most passenger vehicles, although many (particularly light weight vehicles) use [[drum brake]]s on the rear wheels to keep costs and weight down as well as to simplify the provisions for a [[parking brake]]. As the front brakes perform most of the braking effort, this can be a reasonable compromise.\n\nMany early implementations for automobiles located the brakes on the [[inboard brake|inboard]] side of the [[driveshaft]], near the [[differential (mechanics)|differential]], while most brakes today are located inside the wheels. An inboard location reduces the [[unsprung weight]] and eliminates a source of heat transfer to the tires.\n\nHistorically, brake discs were manufactured throughout the world with a strong concentration in Europe and America. Between 1989 and 2005, manufacturing of brake discs migrated predominantly to China.\n\n In 1963 [[Studebaker Avanti]] was made with disc brakes.<ref name="cv">{{cite web |url= http://www.pointhappy.com/cvcars/avanti.htm |title=The Avanti \u2014 Born in Palm Springs |publisher=Point Happy Interactive |access-date=14 December 2015}}</ref> (the [[Bendix Corporation|Bendix]] system was optional on some of the other Studebaker models<ref>{{cite web|title=1963\u20131964 Studebaker Avanti|url= http://auto.howstuffworks.com/1963-1964-studebaker-avanti.htm |publisher=auto.howstuffworks.com |author=Auto Editors of''Consumer Guide''|date=17 December 2007 |access-date=14 December 2015}}</ref>). Front disc brakes became standard equipment in 1965 on the [[Rambler Marlin]]<ref>{{cite web|title=Introduction to the 1965\u20131967 AMC Marlin |url= http://auto.howstuffworks.com/1965-1967-amc-marlin.htm/printable |publisher=auto.howstuffworks.com |author=Auto Editors of ''Consumer Guide'' |date=26 October 2007 |access-date=14 December 2015}}</ref> (the Bendix units were optional on all [[American Motors]]' [[Rambler Classic]] and [[AMC Ambassador|Ambassador]] models<ref name="whatsnewAMC">{{cite journal |title=What's new at American Motors |journal=Popular Science |volume=185 |issue=4 |pages=90\u201391 |date=October 1964 |url= https://books.google.com/books?id=1yUDAAAAMBAJ&q=What's+new+at+American+Motors+1965&pg=PA90 |access-date=14 December 2015}}</ref>), as well as on the [[Ford Thunderbird (fourth generation)|Ford Thunderbird]],<ref>{{cite book|last=Long |first=Brian |title=The Book of the Ford Thunderbird from 1954 |year=2007 |publisher=Veloce Publishing |isbn=978-1-904788-47-8|url= https://books.google.com/books?id=6Xrl9QmUyRAC&q=disc+brakes+1965+Ford+Thunderbird&pg=PA104 |page=104 |access-date=11 November 2010}}</ref> and the [[Lincoln Continental]].<ref>{{cite web|title=1964\u20131965 Lincoln Continental|url= http://auto.howstuffworks.com/1964-1965-lincoln-continental.htm/printable |publisher=auto.howstuffworks.com |author=Auto Editors of''Consumer Guide'' |date=27 November 2007 |access-date=14 December 2015}}</ref> A four-wheel disc brake system was also introduced in 1965 on the [[Chevrolet Corvette (C2)|Chevrolet Corvette]] Stingray.<ref>{{cite web|title=1965 Corvette|url= http://auto.howstuffworks.com/1965-corvette.htm |publisher=auto.howstuffworks.com |author=Auto Editors of ''Consumer Guide'' |date=14 December 2015 |access-date=14 December 2015}}</ref> Most U.S. cars switched from front drum brakes to front disk brakes in the late 1970s and early 1980s.\n\n The first motorcycles to use disc brakes were racing vehicles. [[MV Agusta]] was the first to offer a front disc brake motorcycle to the public on a small scale in 1965, on their relatively expensive [[MV Agusta 600|600 touring motorcycle]], using a mechanical brake linkage.<ref name=Frank2003>{{cite book |title= Honda Motorcycles |first=Aaron |last=Frank |publisher=MotorBooks/MBI |year=2003 |isbn=0-7603-1077-7 |page=80 }}</ref> In 1969 Honda introduced the more affordable [[Honda CB750|CB750]], which had a single hydraulically-actuated front disc brake (and a rear drum brake), and which sold in huge numbers.<ref name=Frank2003/> Disc brakes are now common on motorcycles, [[moped]]s and even [[mountain bike]]s."}},
{"article_title": "Drum brake", "pageid": "59722", "revid": "1062404899", "timestamp": "2021-12-28T07:40:50Z", "history_paths": [["Drum brake --- Introduction ---", "History"]], "categories": ["vehicle braking technologies", "brakes"], "heading_tree": {"Drum brake --- Introduction ---": {"History": {}, "Components": {"Backing plate": {}, "Brake drum": {}, "Wheel cylinder": {}, "Brake shoe": {}}, "In operation": {"Normal braking": {}, "Automatic self-adjustment": {}, "Parking/emergency brake": {}}, "Self-applying characteristic": {}, "Drum brake designs": {}, "Advantages": {}, "As a driveshaft parking/emergency brake": {}, "Disadvantages": {}, "Safety": {}, "Re-arcing": {}, "Use in music": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Drum brake --- Introduction ---|History": "[[File:Tipologia tamburo.svg|thumb|Several schemes of drum brake operation; the distribution force during the braking phase is highlighted in black.]]\nThe modern [[automobile]] drum brake was first used in a car made by [[Wilhelm Maybach|Maybach]] in 1900, although the principle was only later patented in 1902 by [[Louis Renault (industrialist)|Louis Renault]]. He used woven asbestos lining for the drum brake lining, as no alternative dissipated heat like the asbestos lining, though [[Maybach]] had used a less sophisticated drum brake. In the first drum brakes, levers and rods or cables operated the shoes mechanically. From the mid-1930s, oil pressure in a small [[wheel cylinder]] and [[piston]]s (as in the picture) operated the brakes, though some vehicles continued with purely mechanical systems for decades. Some designs have two wheel cylinders.\n\nAs the shoes in drum brakes wear, brakes required regular manual adjustment until the introduction of self-adjusting drum brakes in the 1950s. Drum brakes are also prone to [[brake fade]] with repeated use.<ref>{{cite web |url=http://www.crashforensics.com/brakefailure.cfm |title=Archived copy |access-date=2015-05-19 |url-status=dead |archive-url=https://web.archive.org/web/20150409074407/http://www.crashforensics.com/brakefailure.cfm |archive-date=2015-04-09 }}</ref>\n\n[[Jaguar Cars]] fielded three cars equipped with [[disc brake]]s at [[1953 24 Hours of Le Mans|Le Mans]] in 1953, where they won, in large part due to their superior braking over drum-equipped rivals.<ref>{{Cite web |url=http://www.motorsportmagazine.com/race/sports-cars/le-mans/le-mans-1953-jaguars-gigantic-leap/ |title=Archived copy |access-date=2015-05-19 |archive-date=2015-09-05 |archive-url=https://web.archive.org/web/20150905102834/http://www.motorsportmagazine.com/race/sports-cars/le-mans/le-mans-1953-jaguars-gigantic-leap/ |url-status=dead }}</ref> This spelled the beginning of the end for drum brakes in passenger cars. From the 1960s to the 1980s, disc brakes gradually replaced drum brakes on the front wheels of cars (which receive the majority of braking force). Now practically all cars use disc brakes on the front wheels, and many use disc brakes on all four wheels.\n\nIn the United States, the [[Jeep CJ-5]] (manufactured by [[AM General]]) was the final automobile (produced for the United States Postal Service) to use front drum brakes when it was phased out in 1986. However, drum brakes are still often used on the rear wheels, and for [[parking brake]]s. Some vehicles utilize a "drum-in-hat" parking brake, where the brake shoes are arranged inside the center portion (hat) of a disc brake rotor, which acts as the drum.<ref>{{Cite web|title=Drum-In-Hat Parking Brake Kits|url=https://www.carlsonqualitybrakeparts.com/wp-content/uploads/2018/12/Carlson-Drum-In-Hat-Parking-Brake-Kits-Flyer-2018.pdf|access-date=2020-10-17}}</ref>\n\nEarly brake shoes contained [[asbestos]]. When working on brake systems of older cars, care must be taken not to inhale any dust present in the brake assembly. After the United States Federal Government began to regulate asbestos production, brake manufacturers had to switch to non-asbestos linings. Owners initially complained of poor braking with the replacements, but brake technology eventually advanced to compensate. A majority of daily-driven older vehicles have been fitted with asbestos-free linings. Many other countries have also prohibited the use of asbestos in brakes."}},
{"article_title": "Smart card", "pageid": "59957", "revid": "1062647200", "timestamp": "2021-12-29T18:20:51Z", "history_paths": [["Smart card --- Introduction ---", "History"]], "categories": ["smart cards", "banking technology", "german inventions", "iso standards", "ubiquitous computing", "authentication methods"], "heading_tree": {"Smart card --- Introduction ---": {"History": {"Invention": {}, "Carte bleue": {}, "EMV": {}, "Development of contactless systems": {}, "Complex smart cards": {"Functionalities": {"One time password": {}, "Account information": {}, "Transaction security": {}, "User authentication": {}}, "Components": {"Buttons": {}, "Buzzer": {}, "Display": {}, "Cryptoprocessor": {}, "Power supply": {}}, "Manufacturing": {}, "Card life cycle": {}}, "History and major players": {"AudioSmartCard": {}, "CardLab Innovation": {}, "Coin": {}, "Ellipse World, Inc.": {}, "EMue Technologies": {}, "Feitian Technologies": {}, "Fingerprint Cards": {}, "Giesecke+Devrient": {}, "Gemalto": {}, "Idemia": {}, "Idex": {}, "Innovative Card Technologies": {}, "NagraID": {}, "NagraID Security": {}, "nCryptone": {}, "Oberthur Technologies, now Idemia": {}, "Plastc": {}, "Stratos": {}, "Swyp": {}}, "Businesses": {}}, "Design": {"Internal structure": {"Data structures": {}, "Logical layout": {}}, "Physical interfaces": {"Contact smart cards": {}, "Contactless smart cards": {}, "Hybrids": {}, "USB": {}}, "Logical interfaces": {"Reader side": {}, "Application side": {}}}, "Applications": {"Financial": {}, "SIM": {}, "Identification": {}, "Public transit": {}, "Video games": {}, "Computer security": {}, "Schools": {}, "Healthcare": {}, "Other uses": {}, "Multiple-use systems": {}}, "Security": {}, "Benefits": {}, "Advantages": {}, "Smart cards and electronic commerce": {}, "Disadvantages": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Smart card --- Introduction ---|History": "{{See also|Payment card}}\n\nThe basis for the smart card is the [[silicon]] [[integrated circuit]] (IC) chip.<ref name="Chen">{{cite book |last1=Chen |first1=Zhiqun |title=Java Card Technology for Smart Cards: Architecture and Programmer's Guide |date=2000 |publisher=[[Addison-Wesley Professional]] |isbn=9780201703290 |pages=[https://archive.org/details/javacardtmtechno00zhiq/page/3 3]-4 |url=https://archive.org/details/javacardtmtechno00zhiq|url-access=registration }}</ref> It was invented by [[Robert Noyce]] at [[Fairchild Semiconductor]] in 1959, and was made possible by [[Mohamed M. Atalla]]'s silicon [[surface passivation]] process (1957) and [[Jean Hoerni]]'s [[planar process]] (1959).<ref>{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=[[Springer Science & Business Media]] |isbn=9783540342588 |pages=120 & 321\u2013323}}</ref><ref name="Bassett46">{{cite book |last1=Bassett |first1=Ross Knox |title=To the Digital Age: Research Labs, Start-up Companies, and the Rise of MOS Technology |date=2007 |publisher=[[Johns Hopkins University Press]] |isbn=9780801886393 |page=46 |url=https://books.google.com/books?id=UUbB3d2UnaAC&pg=PA46}}</ref><ref name="Sah">{{cite journal |last=Sah |first=Chih-Tang |author-link=Chih-Tang Sah |title=Evolution of the MOS transistor-from conception to VLSI |journal=[[Proceedings of the IEEE]] |date=October 1988 |volume=76 |issue=10 |pages=1280\u20131326 (1290) |doi=10.1109/5.16328 |url=http://www.dejazzer.com/ece723/resources/Evolution_of_the_MOS_transistor.pdf |issn=0018-9219 |bibcode=1988IEEEP..76.1280S |quote=Those of us active in silicon material and device research during 1956{{ndash}}1960 considered this successful effort by the Bell Labs group led by Atalla to stabilize the silicon surface the most important and significant technology advance, which blazed the trail that led to silicon integrated circuit technology developments in the second phase and volume production in the third phase.}}</ref> The invention of the silicon integrated circuit led to the idea of incorporating it onto a plastic card in the late 1960s.<ref name="Chen"/> Smart cards have since used [[MOS integrated circuit]] chips, along with [[MOS memory]] technologies such as [[flash memory]] and [[EEPROM]] (electrically [[erasable programmable read-only memory]]).<ref>{{cite book |last1=Veendrick |first1=Harry J. M. |title=Nanometer CMOS ICs: From Basics to ASICs |date=2017 |publisher=Springer |isbn=9783319475974 |page=315 |url=https://books.google.com/books?id=Lv_EDgAAQBAJ&pg=PA315}}</ref>\n\n [[File:Prototype moreno2.jpg|thumb|One of the first smart card prototypes, created by its inventor [[Roland Moreno]] around 1975. The chip has not yet been miniaturized. On this prototype, one can see how each pin of the microchip (center) is connected to the exterior world by a copper connector.]]\n[[File:1979 erste G&D-Chipkarte (8 Kontakte).jpg|thumb|First smart card manufactured by [[Giesecke+Devrient|Giesecke & Devrient]] in 1979, already with the finally standardized dimension (ID-1) and a contact area with eight pads (initially on the upper left corner)]]\n\nThe idea of incorporating an [[integrated circuit]] chip onto a plastic card was first introduced by two German engineers in the late 1960s, [[Helmut Gr\u00f6ttrup]] and [[J\u00fcrgen Dethloff]].<ref name="Chen"/> In February 1967, Gr\u00f6ttrup filed the [[patent]] DE1574074<ref>{{Cite patent|title=Nachahmungssicherer Identifikationsschalter|country=DE|number=1574074|status=application|pubdate=1971-11-25|invent1=Gr\u00f6ttrup|inventor1-first=Helmut|fdate=1967-02-06|inventorlink=Helmut Gr\u00f6ttrup|url=}}</ref> in [[West Germany]] for a tamper-proof identification switch based on a [[semiconductor device]]. Its primary use was intended to provide individual copy-protected keys for releasing the tapping process at unmanned gas stations. In September 1968, Helmut Gr\u00f6ttrup, together with Dethloff as an investor, filed further patents for this identification switch, first in [[Austria]]<ref>{{Cite patent|title=Identifizierungsschalter|country=AT|number=287366|status=patent|gdate=1971-01-21|invent1=Dethloff|inventor1-first=J\u00fcrgen|fdate=1968-09-13|pridate=1968-09-13|invent2=Gr\u00f6ttrup|inventor2-first=Helmut|inventorlink=J\u00fcrgen Dethloff|inventorlink2=Helmut Gr\u00f6ttrup|assign1=Intelectron Patentverwaltung}}</ref> and in 1969 as subsequent applications in the [[United States]],<ref>{{Cite patent|title=Identification System|country=US|number=3641316|status=patent|gdate=1972-02-08|invent1=Dethloff|inventor1-first=J\u00fcrgen|fdate=1970-08-17|pridate=1969-06-30|invent2=Gr\u00f6ttrup|inventor2-first=Helmut|inventorlink=J\u00fcrgen Dethloff|inventorlink2=Helmut Gr\u00f6ttrup}}</ref><ref>{{Cite patent|title=Identification Switch|country=US|number=3678250|status=patent|gdate=1972-07-18|invent1=Dethloff|inventor1-first=J\u00fcrgen|fdate=1969-09-15|pridate=1968-09-13|invent2=Gr\u00f6ttrup|inventor2-first=Helmut|inventorlink=J\u00fcrgen Dethloff|inventorlink2=Helmut Gr\u00f6ttrup}}</ref> [[Great Britain]], West Germany and other countries.<ref>{{Cite book|title=From Eurocheque Card to Mobile Security 1968-2012|last1=B\u00f6ttge|first1=Horst|publisher=Battenberg Gietl Verlag|year=2013|isbn=978-3866465497|last2=Mahl|first2=Tobias|last3=Kamp|first3=Michael|editor-last=[[Giesecke+Devrient]]}}</ref>\n\nIndependently, Kunitaka Arimura of the Arimura Technology Institute in Japan developed a similar idea of incorporating an integrated circuit onto a plastic card, and filed a smart card patent in March 1970.<ref name="Chen"/><ref name="Jurgensen">{{cite book |last1=Jurgensen |first1=Timothy M. |last2=Guthery |first2=Scott B. |title=Smart Cards: The Developer's Toolkit |date=2002 |publisher=[[Prentice Hall Professional]] |isbn=9780130937308 |pages=2\u20133 |url=https://books.google.com/books?id=TyniOOmvzKEC&pg=PA2}}</ref> The following year, Paul Castrucci of [[IBM]] filed an American patent titled "Information Card" in May 1971.<ref name="Jurgensen"/>\n\nIn 1974 [[Roland Moreno]] patented a secured memory card later dubbed the "smart card".<ref name=cwhrmoreno>{{cite web|title=Monticello Memoirs Program|url=http://www.cwhonors.org/Search/his_8.asp|publisher=Computerworld honors|access-date=13 February 2012|url-status=dead|archive-url=https://web.archive.org/web/20160303193616/http://www.cwhonors.org/Search/his_8.asp|archive-date=3 March 2016}}</ref><ref>{{Cite web\n |url = http://www.cardwerk.com/smartcards/smartcard_history.aspx\n |title = history of smartcard invention\n |access-date = 29 July 2016\n}}</ref> In 1976, J\u00fcrgen Dethloff introduced the known element (called "the secret") to identify gate user as of USP 4105156.<ref>{{cite web|url=http://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=19780808&DB=EPODOC&locale=en_EP&CC=US&NR=4105156A&KC=A&ND=4 |title=Espacenet \u2013 Original document |publisher=Worldwide.espacenet.com |date=1978-08-08 |access-date=2014-02-13}}</ref>\n\nIn 1977, Michel Ugon from [[Groupe Bull|Honeywell Bull]] invented the first [[microprocessor]] smart card with two [[integrated circuit|chips]]: one microprocessor and one [[computer memory|memory]], and in 1978, he patented the self-programmable one-chip microcomputer (SPOM) that defines the necessary architecture to program the chip. Three years later, [[Motorola]] used this patent in its "CP8". At that time, Bull had 1,200 patents related to smart cards. In 2001, Bull sold its CP8 division together with its patents to [[Schlumberger]], who subsequently combined its own internal smart card department and CP8 to create [[Axalto]]. In 2006, Axalto and Gemplus, at the time the world's top two smart-card manufacturers, merged and became [[Gemalto]]. In 2008, Dexa Systems spun off from Schlumberger and acquired Enterprise Security Services business, which included the smart-card solutions division responsible for deploying the first large-scale smart-card management systems based on [[public key infrastructure]] (PKI).\n\nThe first mass use of the cards was as a [[telephone card]] for payment in French [[payphone]]s, starting in 1983.{{Citation needed|date=May 2012}}\n\n After the T\u00e9l\u00e9carte, microchips were integrated into all French ''[[Carte Bleue]]'' [[debit card]]s in 1992. Customers inserted the card into the merchant's [[point-of-sale]] (POS) terminal, then typed the [[personal identification number]] (PIN), before the transaction was accepted. Only very limited transactions (such as paying small [[Electronic toll collection|highway tolls]]) are processed without a PIN.\n\nSmart-card-based "[[Stored value card|electronic purse]]" systems store funds on the card, so that readers do not need network connectivity. They entered European service in the mid-1990s. They have been common in Germany ([[Geldkarte]]), Austria ([[Quick Wertkarte]]), [[Belgium]] ([[Proton (bank card)|Proton]]), France ([[Moneo]]<ref>[http://www.moneo.net Moneo's website] (in French).</ref>), the Netherlands ([[Chipknip]] Chipper (decommissioned in 2015)), Switzerland ("Cash"), Norway ("[[Mondex]]"), Spain ("Monedero 4B"), Sweden ("Cash", decommissioned in 2004), Finland ("Avant"), UK ("Mondex"), Denmark ("Danm\u00f8nt") and Portugal ("Porta-moedas Multibanco").\nPrivate electronic purse systems have also been deployed such as the Marines corps (USMC) at Parris Island allowing small amount payments at the cafeteria.\n\nSince the 1990s, smart cards have been the [[subscriber identity module]]s (SIMs) used in [[GSM]] mobile-phone equipment. Mobile phones are widely used across the world, so smart cards have become very common.\n\n {{details|EMV}}\nEuropay MasterCard Visa (EMV)-compliant cards and equipment are widespread with the deployment led by European countries. The United States started later deploying the EMV technology in 2014, with the deployment still in progress in 2019. Typically, a country's national payment association, in coordination with [[MasterCard]] International, [[Visa Inc.|Visa]] International, [[American Express]] and [[Japan Credit Bureau]] (JCB), jointly plan and implement EMV systems.\n\nHistorically, in 1993 several international payment companies agreed to develop smart-card specifications for [[debit card|debit]] and [[credit card]]s. The original brands were MasterCard, Visa, and [[Europay]]. The first version of the EMV system was released in 1994. In 1998 the specifications became stable.\n\nEMVCo maintains these specifications. EMVco's purpose is to assure the various financial institutions and retailers that the specifications retain backward compatibility with the 1998 version. EMVco upgraded the specifications in 2000 and 2004.<ref>[http://www.emvco.org/ EMVco]</ref>\n\nEMV compliant cards were first accepted into Malaysia in 2005<ref>{{cite news |url=http://www.therakyatpost.com/business/2015/10/14/us-learns-from-malaysia-10-years-later/|title=US learns from Malaysia, 10 years later|newspaper=The Rakyat Post}}</ref> and later into United States in 2014. MasterCard was the first company that was allowed to use the technology in the United States. The United States has felt pushed to use the technology because of the increase in [[identity theft]]. The credit card information stolen from Target in late 2013 was one of the largest indicators that American credit card information is not safe. Target made the decision on April 30, 2014 that it would try to implement the smart chip technology in order to protect itself from future credit card identity theft.\n\nBefore 2014, the consensus in America was that there were enough security measures to avoid credit card theft and that the smart chip was not necessary. The cost of the smart chip technology was significant, which was why most of the corporations did not want to pay for it in the United States. The debate finally ended when Target sent out a notice<ref>{{Cite web|url=https://corporate.target.com/article/2013/12/important-notice-unauthorized-access-to-payment-ca|title = A message from CEO Gregg Steinhafel about Target's payment card issues}}</ref> stating unauthorized access to magnetic strips<ref>{{Cite news|url=https://www.npr.org/sections/alltechconsidered/2014/01/23/264910138/target-hack-a-tipping-point-in-moving-away-from-magnetic-stripes|title=Target Hack a Tipping Point in Moving Away from Magnetic Stripes|newspaper=NPR.org}}</ref> costing Target over 300 million dollars<ref>{{Cite web|url=https://www.thesslstore.com/blog/2013-target-data-breach-settled/|title = Cost of 2013 Target Data Breach Nears $300 Million|date = 26 May 2017}}</ref> along with the increasing cost of online credit theft was enough for the United States to invest in the technology. The adaptation of EMV's increased significantly in 2015 when the [https://sumup.com/business-guide/emv-liability-shift-explained/ liability shifts] occurred in October by the credit card companies.\n\n {{see also|Contactless payment}}\n''Contactless'' smart cards do not require physical contact between a card and reader. They are becoming more popular for payment and ticketing. Typical uses include mass transit and motorway tolls. Visa and MasterCard implemented a version deployed in 2004\u20132006 in the U.S., with Visa's current offering called [[Visa Inc.#Visa Contactless (formerly payWave)|Visa Contactless]]. Most contactless fare collection systems are incompatible, though the [[MIFARE]] Standard card from [[NXP Semiconductors]] has a considerable market share in the US and Europe.\n\nUse of "Contactless" smart cards in transport has also grown through the use of low cost chips NXP Mifare Ultralight and paper/card/PET rather than PVC. This has reduced media cost so it can be used for low cost tickets and short term transport passes (up to 1 year typically). The cost is typically 10% that of a PVC smart card with larger memory. They are distributed through vending machines, ticket offices and agents. Use of paper/PET is less harmful to the environment than traditional PVC cards.\n\nSmart cards are also being introduced for identification and entitlement by regional, national, and international organizations. These uses include citizen cards, drivers\u2019 licenses, and patient cards. In [[Malaysia]], the compulsory national ID [[MyKad]] enables eight applications and has 18 million users. Contactless smart cards are part of [[ICAO]] [[biometric passport]]s to enhance security for international travel.\n\n \nComplex Cards are smart cards that conform to the [[ISO/IEC 7810]] standard and include components in addition to those found in traditional single chip smart cards. Complex Cards were invented by Cyril Lalo and Philippe Guillaud in 1999 when they designed a chip smart card with additional components, building upon the initial concept consisting of using audio frequencies to transmit data patented by Alain Bernard.<ref>{{cite web |last1=Bernard |first1=Alain |title=Electronic telephone device |url=https://patents.google.com/patent/US5182767A/en |website=Google Patents |access-date=April 29, 2021}}</ref> The first Complex Card prototype was developed collaboratively by Cyril Lalo and Philippe Guillaud , who were working at AudioSmartCard<ref>{{cite web |title=AudioSmartCard |url=https://www.infogreffe.com/entreprise-societe/391975125-audiosmartcard-international-sa-750196B12386.html |website=Infogreffe |publisher=French Commercial Court |access-date=29 April 2021}}</ref> at the time, and Henri Boccia and Philippe Patrice, who were working at [[Gemalto#Gemplus|Gemplus]]. It was ISO 7810-compliant and included a battery, a piezoelectric buzzer, a button, and delivered audio functions, all within a 0.84mm thickness card.\n\nThe Complex Card pilot, developed by AudioSmartCard, was launched in 2002 by [[Cr\u00e9dit Lyonnais]], a French financial institution. This pilot featured acoustic tones as a means of authentication. Although Complex Cards were developed since the inception of the smart card industry, they only reached maturity after 2010.\n\nComplex Cards can accommodate various peripherals including:\n* One or more buttons,\n* A digital keyboard,\n* An alphabetic keyboard,\n* A touch keyboard,\n* A small display, for a dynamic [[Card security code|Card Security Code (CSC)]] for instance,\n* A larger digital display, for OTP or balance, QR code\n* An alphanumeric display, \n* A [[fingerprint sensor]],\n* A LED, \n* A buzzer or speaker.\n\nWhile first generation Complex Cards were battery powered, the second generation is battery-free and receives power through the usual card connector and/or induction .\n\nSound, generated by a buzzer, was the preferred means of communication for the first projects involving Complex Cards. Later, with the progress of displays, visual communication is now present in almost all Complex Cards.\n\n \nComplex Cards support all communication protocols present on regular smart cards: contact, thanks to a contact pad as defined [[ISO/IEC 7816]]  standard, contactless following the [[ISO/IEC 14443]]  standard, and magstripe.\n\nDevelopers of Complex Cards target several needs when developing them: \n* One Time Password, \n* Provide account information,  \n* Provide computation capabilities,  \n* Provide a means of transaction security, \n* Provide a means of user authentication.\n\n \nA Complex Card can be used to compute a cryptographic value, such as a [[One-time password]]. The One-Time Password is generated by a [[Secure cryptoprocessor|cryptoprocessor]] encapsulated in the card. In order to implement this function, the cryptoprocessor must be initialized with a seed value, which enables the identification of the OTPs respective of each card. The hash of seed value has to be stored securely within the card to prevent unauthorized prediction of the generated OTPs.\n\nOne-Time Passwords generation is based either on incremental values (event based) or on a real time clock (time based). Using clock-based One-Time Password generation requires the Complex Card to be equipped with a [[Real-time clock]] and a [[Crystal oscillator|quartz]].\n\nComplex Cards used to generate One Time Password have been developed for: \n* Standard Chartered,<ref>{{cite news |last1=Liau |first1=Yun Qing |title=MasterCard launching banking card with OTP capability |url=https://www.zdnet.com/article/mastercard-launching-banking-card-with-otp-capability/ |access-date=12 May 2021 |publisher=ZDNet |date=November 8, 2012}}</ref> Singapore,\n* Bank of America,<ref>{{cite web |last1=GamerStuff |title=CES 2012: Interview Cyril Lalo NagraID Security |url=https://www.youtube.com/watch?v=xIEHHZH9br8  |archive-url=https://ghostarchive.org/varchive/youtube/20211211/xIEHHZH9br8| archive-date=2021-12-11 |url-status=live|website=YouTube |access-date=12 May 2021 |date=24 January 2012}}{{cbignore}}</ref> USA, \n* Erste Bank, Croatia, \n* Verisign,<ref>{{cite web |title=Mastercard, Symantec and NagraID Security team up to provide further payment card security features |url=https://www.nagra.com/media-center/press-releases/mastercard-symantec-and-nagraid-security-team-provide-further-payment |website=www.nagra.com |access-date=12 May 2021 |date=14 February 2011}}</ref> USA,\n* RSA Security.<ref>{{cite news |title=RSA SecurID SD200 - hardware token Series Specs |url=https://www.cnet.com/products/rsa-securid-sd200-hardware-token-series/ |access-date=12 May 2021 |publisher=CNet}}</ref>\n\n \nA Complex Card with buttons can display the balance of one or multiple account(s) linked  to the card. Typically, either one button is used to display the balance in the case of a single account card or, in the case of a card linked to multiple accounts, a combination of buttons is used to select a specific account's balance.\n\nFor additional security, features such as requiring the user to enter an identification or a security value such as a [[Personal identification number|PIN]] can be added to a Complex Card.\n\nComplex Cards used to provide account information have been developed for: \n* Getin Bank, Poland,<ref>{{cite news |last1=Getin Bank |title=Getin Bank - poznaj now\u0105 Kart\u0119 Display do konta bankowego |url=https://www.youtube.com/watch?v=lek_px4wcXQ |access-date=21 May 2021 |publisher=YouTube |date=7 June 2013 |language=Polish}}</ref>\n* TEB, Turkey.\n\nThe latest generation of battery free, button free, Complex Cards can display a balance or other kind of information without requiring any input from the card holder. The information is updated during the use of the card. For instance, in a transit card, key information such as the monetary value balance, the number of remaining trips or the expiry date of a transit pass can be displayed.\n\n \nA Complex Card being deployed as a payment card can be equipped with capability to provide transaction security. Typically, online payments are made secure thanks to the [[Card security code|Card Security Code (CSC)]], also known as card verification code (CVC2),  or card verification value (CVV2). The card security code (CSC) is a 3 or 4 digits number printed on a credit or debit card, used as a security feature for [[Card not present transaction|card-not-present (CNP)]] payment card transactions to reduce the incidence of fraud.\n\nThe Card Security Code (CSC) is to be given to the merchant by the cardholder in order to complete a card-not-present transaction. The CSC is transmitted along with other transaction data and verified by the card issuer. The [[Payment Card Industry Data Security Standard|Payment Card Industry Data Security Standard (PCI DSS)]] prohibits the storage of the CSC by the merchant or any stakeholder in the payment chain. Although designed to be a security feature, the static CSC is susceptible to fraud as it can easily be memorized by a shop attendant, who could then use it for fraudulent online transactions or sale on the dark web. \n \nThis vulnerability has led the industry to develop a Dynamic Card Security Code (DCSC) that can be changed at certain time intervals, or after each contact or contactless EMV transaction. This Dynamic CSC brings significantly better security than a static CSC.\n\nThe first generation of Dynamic CSC cards, developed by NagraID Security required a battery, a quartz and Real Time Clock (RTC) embedded within the card to power the computation of a new Dynamic CSC, after expiration of the programmed period.\n\nThe second generation of Dynamic CSC cards, developed by Ellipse World, Inc. , does not require any battery, quartz, or RTC to compute and display the new dynamic code. Instead, the card obtains its power either through the usual card connector or by induction during every EMV transaction from the Point of Sales (POS) terminal or Automated Teller Machine (ATM) to compute a new DCSC.\n\nThe Dynamic CSC, also called dynamic cryptogram, is marketed by several companies, under different brand names: \n* MotionCode, first developed by NagraID Security, a company later acquired by [[IDEMIA|Idemia]], \n* DCV, the solution offered by [[Gemalto|Thales]],\n* EVC (Ellipse Verification Code) by Ellipse, a Los Angeles, USA based company.\n\nThe advantage of the Dynamic Card Security Code (DCSC) is that new information is transmitted with the payment transactions, thus making it useless for a potential fraudster to memorize or store it. A transaction with a Dynamic Card Security Code is carried out exactly the same way, with the same processes and use of parameters as a transaction with a static code in a card-not-present transaction. Upgrading to a DCSC allows cardholders and merchants to continue their payment habits and processes undisturbed.\n\n \nComplex Cards can be equipped with biometric sensors allowing for stronger user authentication. In the typical use case, fingerprint sensors are integrated into a payment card to bring a higher level of user authentication than a PIN.\n\nIn order to implement user authentication using a fingerprint enabled smart card, the user has to authenticate himself/herself to the card by means of the fingerprint before starting a payment transaction.\n\nSeveral companies<ref>{{cite web |last1=D'Albore |first1=Antonio |title=The rise of biometric cards |date=5-6 October 2017 |url=http://icma.com/wp-content/uploads/2017/10/The-Rise-of-Biometric-Cards10-4.pdf |publisher=Embedded Security News |website=International Card Manufacturers Association |access-date=2021-10-26}}</ref> offer cards with fingerprint sensors: \n* [[Gemalto|Thales]]: Biometric card, \n* [[IDEMIA|Idemia]]: F.Code, originally developed by NagraID Security,\n* [[IDEX Biometrics|Idex Biometrics]], \n* [[NXP Semiconductors]], \n* \u2026\n\n \nComplex Cards can incorporate a wide variety of components. The choice of components drives functionality, influences cost, power supply needs, and manufacturing complexity.\n\n \nDepending on Complex Card types, buttons have been added to allow an easy interaction between the user and the card. Typically, these buttons are used to:\n* Select one action, such as which account to obtain the balance, or the unit (''e.g.'' currency or number of trips) in which the information is displayed,\n* Enter numeric data via the addition of a digital keypad,\n* Enter text data via the addition of an alphanumeric keyboard.\n\nWhile [[Membrane keyboard|separate keys]] have been used on prototypes in the early days, capacitive keyboards are the most popular solution now, thanks to technology developments by AudioSmartCard International SA.<ref>{{cite web |title=Infogreffe - AudioSmartCard International SA |url=https://www.infogreffe.com/entreprise-societe/391975125-audiosmartcard-international-sa-750196B12386.html |website=Infogreffe |publisher=French corporate register |access-date=12 June 2021}}</ref>\n\nThe interaction with a capacitive keyboard requires constant power, therefore a battery and a mechanical button are required to activate the card.\n\n \nThe first Complex Cards were equipped with a buzzer that made it possible to broadcast sound. This feature was generally used over the phone to send identification data such as an identifier and One-Time Passwords (OTPs). Technologies used for sound transmission include DTMF ([[Dual-tone multi-frequency signaling]]) or FSK ([[Frequency-shift keying]]).\n\nCompanies that offered cards with buzzers include: \n* AudioSmartCard, \n* nCryptone,<ref>{{cite web |title=Bloomberg - nCryptone |url=https://www.bloomberg.com/profile/company/758050Z:FP |website=Bloomberg |publisher=Bloomberg |access-date=12 June 2021}}</ref>\n* Prosodie,\n* Soci\u00e9t\u00e9 d'exploitation du jeton s\u00e9curis\u00e9 \u2013 SEJS.\n\n \nDisplaying data is an essential part of Complex Card functionalities. Depending on the information that needs to be shown, displays can be digital or alphanumeric and of varying lengths. Displays can be located either on the front or back of the card. A front display is the most common solution for showing information such as a One-Time Password or an electronic purse balance. A rear display is more often used for showing a Dynamic Card Security Code (DCSC).\n\nDisplays can be made using two technologies: \n* [[Liquid-crystal display]] (LCD) : LCDs are easily available from a wide variety of suppliers, and they are able to display either digits or alphabetical data. However, to be fitted in a complex smart card, LCDs need to have a certain degree of flexibility. Also, LCDs need to be powered to keep information displayed. \n* [[Liquid-crystal display#"Zero-power" (bistable) displays|Bistable displays]], also known as [[Ferroelectric liquid crystal display]]s, are increasingly used as they only require power to refresh the displayed information. The displayed data remains visible, without the need for of any power supply. Bistable displays are also available in a variety of specifications, displaying digits or pixels. Bistable displays are available from E Ink Corporation<ref>{{cite web |title=E Ink |url=https://www.eink.com/index.html |website=E Ink |publisher=E Ink |access-date=12 June 2021}}</ref> among others.\n\n \nIf a Complex smart Card is dedicated to making cryptographic computations such as generating a One-Time Password, it may require a [[secure cryptoprocessor]].\n\n \nAs Complex  Cards  contain more components than traditional smart cards, their power consumption must be carefully monitored.\n\nFirst generation Complex Cards require a power supply even in standby mode. As such, product designers generally included a battery in their design. Incorporating a battery creates an additional burden in terms of complexity, cost, space and flexibility in an already dense design. Including a battery in a Complex Card increases the complexity of the manufacturing process as a battery cannot be hot laminated.\n\nSecond generation Complex Cards feature a battery-free design. These cards harvest the necessary power from external sources; for example when the card interacts in a contact or [[Electromagnetic induction|contactless]] fashion with a payment system or an NFC-enabled smartphone.  The use of a bistable display in the card design ensures that the screen remains legible even when the Complex Card is unconnected to the power source.\n\n \nComplex Card manufacturing methods are inherited from the smart card industry and from the electronics mounting industry. As Complex Cards incorporate several components while having to remain within 0.8 mm thickness and be flexible, and to comply with the [[ISO/IEC 7810]], [[ISO/IEC 7811]] and [[ISO/IEC 7816]] standards, renders their manufacture more complex than standard smart cards.\n\nOne of the most popular manufacturing processes in the smart card industry is lamination. This process  involves  laminating an inlay between two card faces. The inlay contains the needed electronic components with an antenna printed on an inert support.\n\nTypically battery-powered Complex Cards  require a cold lamination manufacturing process. This process impacts the manufacturing lead time and the whole cost of such a Complex Card.\n\nSecond generation, battery-free Complex Cards can be manufactured by existing hot lamination process. This automated process, inherited from traditional smart card manufacturing, enables the production of Complex Cards in large quantities while keeping costs under control, a necessity for the evolution from a niche to a mass market.\n\n \nAs with standard smart cards, Complex Cards go through a lifecycle comprising the following steps: \n* Manufacturing,\n* Personalization,\n* User enrollment, if needed by the application,\n* Provisioning,\n* Active life,\n* Cancellation,\n* Recycling / destruction.\n\nAs Complex Cards bring more functionalities than standard smart cards and, due to their complexity, their personalization can take longer or require more inputs. Having Complex Cards that can be personalized by the same machines and the same processes as regular smart cards allows them to be integrated more easily in existing manufacturing chains and applications.\n\nFirst generation, battery-operated Complex Cards require specific [[Battery recycling|recycling]] processes, mandated by different regulatory bodies. Additionally, keeping battery-operated Complex Cards in inventory for extended periods of time may reduce their performance due to [[Capacity loss|battery ageing]].\n\nSecond-generation battery-free technology ensures operation during the entire lifetime of the card and eliminates self-discharge, providing [[extended shelf life]], and is more eco-friendly.\n\n \nSince the inception of smart cards, innovators have been trying to add extra features. As technologies have matured and have been industrialized, several smart card industry players have been involved in Complex Cards.\n\nThe Complex Card concept began in 1999 when Cyril Lalo and Philippe Guillaud, its inventors, first designed a smart card with additional components. The first prototype was developed collaboratively by Cyril Lalo, who was the CEO of AudioSmartCard at the time, and Henri Boccia and Philippe Patrice, from Gemplus. The prototype  included a button and audio functions on a 0.84mm thick  ISO 7810-compliant card .\n\nSince then, Complex Cards have been mass-deployed primarily by NagraID Security.\n\n \nAudioSmartCard International SA<ref>{{cite web |title=Company Information AudioSmartCard International SA |url=https://www.infogreffe.com/entreprise-societe/391975125-audiosmartcard-international-sa-750196B12386.html |website=Infogreffe |publisher=French Registries at Commercial Courts |access-date=16 July 2021}}</ref> was instrumental in developing the first Complex Card that included a battery, a piezoelectric buzzer, a button,  and audio functions all on a 0.84mm thick, ISO 7810-compatible card.\n\nAudioSmartCard was founded in 1993 and specialized in the development and marketing of acoustic tokens incorporating security features. These acoustic tokens exchanged data in the form of sounds transmitted over a phone line. In 1999, AudioSmartCard transitioned to  a new leadership under Cyril Lalo and Philippe Guillaud, who also became major shareholders. They made AudioSmartCard evolve towards the smart card world. In 2003 Prosodie,<ref>{{cite web |title=Information about Prosodie Corporation |url=https://www.infogreffe.fr/entreprise-societe/411393218-prosodie-920197B043840000/liste-etablissements-1.html |website=Infogreffe |publisher=French commercial court registries |access-date=16 July 2021}}</ref> a subsidiary of [[Capgemini]], joined the shareholders of AudioSmartCard.\n\nAudioSmartCard was renamed nCryptone,<ref>{{cite web |title=nCryptone Corporate Profile |url=https://www.bloomberg.com/profile/company/758050Z:FP |website=Bloomberg |publisher=Bloomberg |access-date=16 July 2021}}</ref> in 2004.\n\n \nCardLab Innovation,<ref>{{cite web |title=CardLab Innovation |url=https://www.cardlab.com |website=CardLab Innovation |publisher=CardLab Innovation |access-date=16 July 2021}}</ref> incorporated in 2006 in Herlev, Denmark, specializes in Complex Cards that include a switch, a biometric reader, an RFID jammer, and one or more magstripes. The company works with manufacturing partners in China and Thailand and owns a card lamination factory in Thailand.\n\n \nCoin was a US-based startup<ref>{{cite web |last1=Cipriani |first1=Jason |title=Coin adds NFC capabilities to its new all-in-one card |url=https://fortune.com/2015/08/27/coin-nfc-update/ |website=Fortune |publisher=Fortune |access-date=16 July 2021}}</ref> founded in 2012 by Kanishk Parashar.<ref>{{cite web |title=LinkedIn: Kanishk Parashar |url=https://www.linkedin.com/in/diamondk/ |website=LinkedIn |publisher=LinkedIn}}</ref> It developed a Complex Card capable of storing the data of several credit and debit cards. The card prototype was equipped with a display<ref>{{cite web |last1=Statt |first1=Nick |title=Inside Coin's techie vision for the all-in-one credit card |url=Inside Coin's techie vision for the all-in-one credit card |website=CNet |publisher=CNet |access-date=16 July 2021}}</ref>{{Full citation needed|date=July 2021}} and a button that enabled the user to switch between different cards. In 2015, the original Coin card concept evolved into Coin 2.0 adding contactless communication to its original magstripe emulation.<ref>{{cite web |last1=Statt |first1=Nick |title=Coin adds NFC capabilities to its new all-in-one card |url=https://www.cnet.com/tech/mobile/inside-coins-techie-vision-for-the-all-in-one-credit-card/ |website=CNet |publisher=CNet |access-date=16 July 2021}}</ref>\n\nCoin was acquired by [[Fitbit]] in May 2016<ref>{{cite web |last1=Cooper |first1=Daniel |title=Fitbit buys Coin to help with mobile payments |url=https://www.engadget.com/2016-05-18-fitbit-buys-coin.html |website=Engadget |publisher=Engadget}}</ref> and all Coin activities were discontinued in February 2017.<ref>{{cite web |last1=Heater |first1=Brian |title=Coin will shut down its product services at the end of February |url=https://techcrunch.com/2017/01/31/coin-shut-down/?guccounter=1 |website=TechCrunch |publisher=TechCrunch |access-date=16 July 2021}}</ref>\n\n \nEllipse World, Inc.<ref>{{cite web |title=Ellipse World Inc. |url=https://www.ellipse.la |website=Ellipse World Inc. |publisher=Ellipse World Inc. |access-date=16 July 2021}}</ref> was founded in 2017 by Cyril Lalo  and S\u00e9bastien Pochic,  both recognized experts in Complex Card technology.   Ellipse  World, Inc. specializes in battery-free Complex Card technology.\n\nThe Ellipse patented technologies enable smart card manufacturers to use their existing dual interface payment card manufacturing process and supply chain to build battery-free,  second generation Complex Cards with display capabilities. Thanks to this ease of integration, smart card vendors are able to address banking, transit and prepaid cards markets.\n\n \nEMue<ref>{{cite web |title=Emue Technologies |url=http://www.emue.com |website=Emue Technologies |publisher=Emue Technologies |access-date=16 July 2021}}</ref> Technologies, headquartered in Melbourne, Australia, designed and developed authentication solutions for the financial services industry from 2009 to 2015.<ref>{{cite web |title=LinkedIn: Emue Technologies |url=https://www.linkedin.com/company/emue-technologies/about/ |website=LinkedIn |publisher=LinkedIn |access-date=16 July 2021}}</ref> The company\u2019s flagship product, developed in collaboration with Cyril Lalo and Philippe Guillaud , was the eMue Card, a Visa CodeSure<ref>{{cite web |title=Visa CodeSure gets commercial green light |url=https://www.finextra.com/newsarticle/21447/visa-codesure-gets-commercial-green-light |website=Finextra |date=2 June 2010 |publisher=Finextra |access-date=16 July 2021}}</ref> credit card with an embedded keypad, a display and a microprocessor.\n\n \n[[Feitian Technologies Co., Ltd.|Feitian Technologies]], a China-based company created in 1998, provides cyber security products and solutions. The company offers security solutions based on smart cards as well as other authentication devices. These include Complex Cards, that incorporate a display,<ref>{{cite web |title=OTP Display Card |url=https://www.ftsafe.com/Products/Power_Card/Standard |website=Feitian technologies |publisher=Feitian technologies |access-date=16 July 2021}}</ref> a keypad<ref>{{cite web |title=Chip Embedded Card |url=https://www.ftsafe.com/Products/Power_Card/Chip |website=Feitian Technologies |publisher=Feitian Technologies |access-date=16 July 2021}}</ref> or a fingerprint sensor.<ref>{{cite web |title=OTP Display Card |url=https://www.ftsafe.com/Products/Power_Card/Fingerprint |website=Feitian Technologies |publisher=Feitian Technologies |access-date=16 July 2021}}</ref>\n\n \n[[Fingerprint Cards]] AB (or Fingerprints<ref>{{cite web |title=Fingerprint Cards |url=https://www.fingerprints.com |website=Fingerprint Cards |publisher=Fingerprint Cards |access-date=16 July 2021}}</ref>) is a Swedish company specializing in biometric solutions. The company sells biometric sensors and has recently introduced payment cards incorporating a fingerprint sensor<ref>{{cite web |title=Biometrics: The missing piece of the contactless card puzzle |url=https://www.fingerprints.com/uploads/2018/05/fpc-smartcards-infographics-v1.pdf |website=Fingerprint Cards |publisher=Fingerprint Cards |access-date=16 July 2021}}</ref> such as  the Zwipe card,<ref>{{cite web |title=Zwipe Payment Card the World's Leading Biometric Payment Card |url=https://www.fingerprints.com/showcase/zwipe-payment-card/ |website=Fingerprint Cards |publisher=Fingerprint Cards |access-date=16 July 2021}}</ref> a biometric dual-interface payment card using an integrated sensor from Fingerprints.\n\n \n[[Giesecke+Devrient|Giesecke & Devrient]], also known as G+D,<ref>{{cite web |title=Giesecke+Devrient |url=https://www.gi-de.com/en/ |website=Giesecke+Devrient |publisher=Giesecke+Devrient |access-date=16 July 2021}}</ref> is a German company headquartered in Munich that provides banknotes, security printing, smart cards and cash handling systems.  Its smart card portfolio  includes display cards, OTP cards, as well as cards displaying a [[#Transaction_security|Dynamic CSC]].\n\n \n[[Gemalto]], a division of [[Thales Group]], is a major player in the secure transaction industry. \nThe company\u2019s  Complex Card portfolio includes cards with a display<ref>{{cite web |title=Payments |url=https://www.gemalto.com/financial/cards/payments |website=Thales Group - Gemalto |publisher=Thales Group - Gemalto |access-date=16 July 2021}}</ref> or a fingerprint sensor.<ref>{{cite web |title=EMV Biometric Card |url=https://www.gemalto.com/financial/cards/emv-biometric-card |website=Thales Group - Gemalto |publisher=Thales Group - Gemalto |access-date=16 July 2021}}</ref> These cards may display an OTP<ref>{{cite web |title=SafeNet OTP Display Card |url=https://cpl.thalesgroup.com/access-management/authenticators/safenet-otp-display-card |website=Thales Group - SafeNet |publisher=Thales Group - SafeNet |access-date=16 July 2021}}</ref> or a Dynamic CSC.<ref>{{cite web |title=Dynamic Code Verification |url=https://www.gemalto.com/financial/cards/payments/dynamic-code-verification |website=Thales Group - Gemalto |publisher=Thales Group - Gemalto |access-date=16 July 2021}}</ref>\n\n \n[[IDEMIA|Idemia]] is the product of the 2017<ref>{{cite web |title=Oberthur Technologies \u2013Morpho becomes IDEMIA, the global leader in trusted identities |url=https://www.idemia.com/public_download/oberthur-technologies-morpho-becomes-idemia-global-leader-trusted-identities |website=Idemia |publisher=Idemia |access-date=16 July 2021}}</ref> merger of Oberthur Technologies and Morpho. The combined company has positioned itself as a global provider of financial cards, SIM cards, biometric devices as well as public and private identity solutions. Due to Oberthur\u2019s acquisition of NagraID Security in 2014, Idemia\u2019s  Complex Card offerings include the F.CODE<ref>{{cite web |title=Biometric payment card |url=https://www.idemia.com/biometric-payment-card |website=Idemia |publisher=Idemia |access-date=16 July 2021}}</ref> biometric payment card that includes a fingerprint sensor, and its battery-powered Motion Code<ref>{{cite web |title=Motion Code |url=https://www.idemia.com/motion-code |website=Idemia |date=13 October 2020 |publisher=Idemia |access-date=16 July 2021}}</ref> card that displays a Dynamic CSC.\n\n \n[[IDEX Biometrics|Idex Biometrics]] ASA, incorporated in Norway, specializes in fingerprint identification technologies for  personal authentication. The company offers fingerprint sensors<ref>{{cite web |title=Fingerprint sensor manufacturer |url=https://www.idexbiometrics.com/products/biometric-fingerprint-sensors/ |website=Idex Biometrics |publisher=Idex Biometrics |access-date=16 July 2021}}</ref> and modules<ref>{{cite web |title=What is a fingerprint sensor module? |url=https://www.idexbiometrics.com/faq/fingerprint-sensors/what-is-a-fingerprint-sensor-module/ |website=Idex Biometrics |publisher=Idex Biometrics |access-date=16 July 2021}}</ref> that are ready to be embedded into cards.<ref>{{cite web |title=XH Smart Tech showcasing dual-interface biometric card with IDEX sensor at Mobile World Congress in Barcelona |url=https://www.idexbiometrics.com/xh-smart-tech-showcasing-dual-interface-biometric-card-with-idex-sensor-at-mobile-world-congress-in-barcelona/ |website=Idex Biometrics |date=25 February 2019 |publisher=Idex Biometrics |access-date=16 July 2021}}</ref>\n\n \nFounded in 2002, by Alan Finkelstein, Innovative Card Technologies developed and commercialized enhancements for the smart card market. The company acquired the display card assets of nCryptone<ref>{{cite news |title=nCryptone monte au capital d'Innovative Card Technologies |url=https://www.journaldunet.com/solutions/dsi/1066019-ncryptone-monte-au-capital-d-innovative-card-technologies/ |access-date=16 July 2021 |publisher=JDN |date=30 June 2006 |language=French}}</ref> in 2006. Innovative Card Technologies has ceased its activities.\n\n \nNagra ID, now known as NID,<ref>{{cite web |title=NID |url=https://www.nagraid.com |website=NID |publisher=NID |access-date=16 July 2021}}</ref> was a wholly-owned subsidiary of the [[Kudelski Group]] until 2014. NID can trace its history with Complex Cards back to 2003 when it collaborated on development with nCryptone. Nagra ID was instrumental in developing the cold lamination process for Complex Cards manufacturing.\n\nNagra ID manufactures Complex Cards<ref>{{cite web |title=Complex Cards |url=https://www.nagraid.com/en/solutions/complex-cards |website=NID |publisher=NID |access-date=16 July 2021}}</ref> that can include a battery, buttons, displays or other electronic components.\n\n \nNagra ID Security began in 2008 as a spinoff of Nagra ID to focus on Complex Card development and manufacturing. The company was owned by [[Kudelski Group]] (50%), Cyril Lalo (25%) and Philippe Guillaud (25%).\n\nNagraID Security quickly became a leading player in the adoption of Complex Cards due, in large part, to its development of MotionCode cards that featured a small display to enable  a [[Card security code|Card Security Code (CVV2)]].\n\nNagraID Security was the first Complex Cards manufacturer to develop a mass market for payment display cards. Their customers included: \n* ABSA,<ref>{{cite web |title=MasterCard and Absa Introduce Next Generation Payment Card, a First for APMEA |url=https://newsroom.mastercard.com/press-releases/mastercard-and-absa-introduce-next-generation-payment-card-a-first-for-apmea/ |website=MasterCard |publisher=MasterCard |access-date=16 July 2021}}</ref> South Africa,\n* Banco Bicentenario, Venezuela,\n* Banco MontePaschi, Belgium,\n* Erste Bank, Croatia, \n* Getin Bank, Poland, \n* Standard Chartered Bank, Singapore.\n\nNagraID Security also delivered One-Time Password cards to companies including: \n* Bank of America,\n* HID Security,\n* Paypal,\n* RSA Security, \n* Verisign.\n\nIn 2014, NagraID Security was sold to [[Oberthur Technologies]] (now [[IDEMIA|Idemia]]).\n\n \nnCryptone emerged in 2004 from the renaming of AudioSmartCard. nCryptone was headed by Cyril Lalo and Philippe Guillaud<ref>{{cite web |title=Philippe Guillaud |url=https://www.epita.fr/2018/11/26/temoignage-ancien-ingenieur-entrepreneur-muzeek-intelligence-artificielle-musique-entreprises-parcours-2018/ |website=Epita |date=26 November 2018 |publisher=Epita |access-date=16 July 2021}}</ref> and developed technologies around authentication servers and devices.\n\nnCryptone display card assets were acquired by Innovative Card Technologies in 2006.<ref>{{cite news |title=nCryptone acquiert IC Tech |url=https://investir.lesechos.fr/actions/actualites/ncryptone-acquiert-ic-tech-141099.php |access-date=16 July 2021 |publisher=Les Echos Investir |date=June 30, 2006 |language=French}}</ref>\n\n \n[[Oberthur Technologies]], now [[IDEMIA|Idemia]], is one of the major players in the secure transactions industry. It acquired the business of NagraID Security in 2014. Oberthur then merged with Morpho and the combined entity was renamed Idemia  in 2017.\n\nMajor references in the Complex Cards business include: \n* BPCE Group,<ref>{{cite web |title=BPCE Group and Oberthur Technologies launch a world-exclusive innovation: the first dynamic cryptogram payment card |url=https://newsroom-en.groupebpce.fr/news/bpce-group-and-oberthur-technologies-launch-a-world-exclusive-innovation-the-first-dynamic-cryptogram-payment-card-e9bc-53927.html |website=BPCE |publisher=BPCE |access-date=16 July 2021}}</ref> France, \n* Orange Bank,<ref>{{cite news |title=Orange Bank : une carte Visa Premium avec cryptogramme dynamique et Apple Pay |url=https://www.igen.fr/ailleurs/2019/03/orange-bank-une-carte-visa-premium-avec-cryptogramme-dynamique-et-apple-pay-107063 |access-date=16 July 2021 |publisher=iGen |date=March 7, 2019 |language=French}}</ref> France, \n* Soci\u00e9t\u00e9 G\u00e9n\u00e9rale,<ref>{{cite web |title=1 million MOTION CODE online transactions with Soci\u00e9t\u00e9 G\u00e9n\u00e9rale |url=https://www.idemia.com/press-release/1-million-motion-code-online-transactions-societe-generale-2017-10-17 |website=Idemia |publisher=Idemia |access-date=16 July 2021}}</ref> France.\n\n \nSet up in 2009, Plastc announced a single card that could digitally hold the data of up to 20 credit or debit cards. The company succeeded in raising US$9 million through preorders but failed to deliver any product.<ref>{{cite news |last1=Hales |first1=Brett |title=R.I.P Plastc and Coin. Death of the 'smartcard' industry. |url=https://hackernoon.com/r-i-p-plastc-and-coin-death-of-the-smartcard-industry-bc243cec913c |publisher=Hackernoon |date=May 12, 2017}}</ref><ref>{{cite news |last1=Schubarth |first1=Cromwell |title=Palo Alto 'smart' credit card startup shutters after taking $9M in pre-orders |url=https://www.bizjournals.com/sanjose/news/2017/04/21/palo-alto-smartcredit-card-startup-shutters-after.html |access-date=16 July 2021 |publisher=Biz Journals |date=April 21, 2017}}</ref> Plastc was then acquired<ref>{{cite magazine |title=Edge Mobile Payments Acquires Plastc Assets |url=https://edgemobilepayments.com/edge-mobile-payments-acquires-plastc |magazine=Edge |publisher=Edge |access-date=16 July 2021}}</ref> in 2017 by Edge Mobile Payments,<ref>{{cite web |title=Edge Mobile Payments |url=https://edgemobilepayments.com |website=Edge Mobile Payments |access-date=16 July 2021}}</ref> a Santa Cruz-based Fintech company. The Plastc project continues as the Edge card,<ref>{{cite web |title=EDGE Mobile Payments Announces Development of the EDGE Card |url=https://edgemobilepayments.com/edge-mobile-payments-announces-development-of-the-edge-card |website=EDGE Mobile Payments |publisher=EDGE Mobile Payments |access-date=16 July 2021}}</ref> a dynamic payment card that consolidates several payment cards in one device. The card is equipped with a battery and an ePaper screen and can store data from up to 50 credit, debit, loyalty and gift cards.\n\n \nStratos<ref>{{cite web |title=Stratos |url=https://cardlabcards.com |website=Stratos |publisher=Stratos |access-date=16 July 2021}}</ref> was created in 2012 in Ann Arbor, Michigan, USA. In 2015, Stratos developed the Stratos Bluetooth Connected Card,<ref>{{cite news |last1=Cipriani |first1=Jason |title=One card to rule them all? Stratos smart card replaces the need for a wallet |url=https://fortune.com/2015/05/13/stratos-smart-card/ |access-date=16 July 2021 |publisher=Fortune |date=May 13, 2015}}</ref> which was designed  to integrate up to three credit and debit card in a single card format and featured a smartphone app used to manage the card. Due to its Lithium ion thin film battery, the Stratos card was equipped with LEDs and communicated in contactless mode and in Bluetooth low Energy.\n\nIn 2017 Stratos was acquired<ref>{{cite web |title=Stratos Connected Card Platform Acquired by CardLab Innovations |url=https://cardlabcards.com/blog/2017/02/15/cardlab-acquisition-announcement/ |website=Stratos |publisher=Stratos |access-date=16 July 2021}}</ref> by CardLab Innovation, a company headquartered in Herlev, Denmark.\n\n \nSWYP<ref>{{cite web |title=Swyp |url=https://www.swypcard.com |website=Swyp |publisher=Swyp |access-date=16 July 2021}}</ref> was the brand name of  a card developed by Qvivr, a company incorporated in 2014 in Fremont, California.  SWYP was introduced in 2015  and dubbed the world\u2019s first smart wallet. SWYP was a metal card with the ability to combine over 25 credit, debit, gift and loyalty cards. The card worked in conjunction with a smartphone app used to manage the cards. The Swyp card included a battery, a button and a matrix display that showed which card was in use. The company registered users in its beta testing program, but the product never shipped on a commercial scale.\n\nQvivr raised US$5 million in January 2017<ref>{{cite news |last1=Magistretti |first1=B\u00e9r\u00e9nice |title=Mobile payment startup Qvivr raises $5 million led by Khosla Ventures |url=https://venturebeat.com/2017/01/31/mobile-payment-startup-qvivr-raises-5-million-led-by-khosla-ventures/ |access-date=16 July 2021 |publisher=VentureBeat |date=January 31, 2017}}</ref> and went out of business in November 2017.\n\n \nComplex Cards have been adopted by numerous financial institutions worldwide. They may include different functionalities such as payment cards (credit, debit, prepaid), [[One-Time Password]], mass-transit, and dynamic [[Card security code|Card Security Code (CVV2)]].\n\nComplex Card technology is used by numerous financial institutions including: \n* ABSA,<ref>{{cite web |title=MasterCard and Absa Introduce Next Generation Payment Card, a First for APMEA |url=https://newsroom.mastercard.com/press-releases/mastercard-and-absa-introduce-next-generation-payment-card-a-first-for-apmea/ |website=MasterCard |publisher=MasterCard |access-date=17 July 2021 |date=November 28, 2012}}</ref> South Africa, \n* Banca MontePaschi Belgio,<ref>{{cite web |title=World first for Belgium: Banca Monte Paschi Belgio and MasterCard launch the first payment card combining debit, credit, display screen and contactless payment facilities |url=https://newsroom.mastercard.com/press-releases/world-first-for-belgium-banca-monte-paschi-belgio-and-mastercard-launch-the-first-payment-card-combining-debit-credit-display-screen-and-contactless-payment-facilities/ |website=MasterCard |publisher=MasterCard |access-date=17 July 2021 |date=23 October 2012}}</ref> \n* Bank of America,<ref>{{cite news |title=Bank of America unveils SafePass card |url=https://www.finextra.com/news/announcement.aspx?pressreleaseid=24783 |access-date=17 July 2021 |agency=Finextra |publisher=Finextra |date=24 November 2008}}</ref> USA, \n* BPCE Group,<ref>{{cite news |last1=Verdict Staff |title=BPCE, Oberthur to pilot first dynamic cryptogram payment card |url=https://www.cardsinternational.com/news/bpce-oberthur-to-pilot-first-dynamic-cryptogram-payment-card-210515-4582123/ |access-date=17 July 2021 |publisher=Cards International |date=May 21, 2015}}</ref> France, \n* Carpatica Bank,<ref>{{cite news |title=Carpatica Bank launches display card in Romania |url=https://business-review.eu/news/carpatica-bank-launches-display-card-in-romania-12929-479 |access-date=17 July 2021 |publisher=Business Review, Romania |date=6 December 2011}}</ref> Romania,  \n* Credit Europe Bank,<ref>{{cite web |title=MasterCard Drives Growth in Its Display Card Programme with Bank Launches in Romania |url=https://newsroom.mastercard.com/press-releases/mastercard-drives-growth-in-its-display-card-programme-with-bank-launches-in-romania/ |website=MasterCard |publisher=MasterCard |access-date=17 July 2021 |date=15 November 2011}}</ref> Romania,  \n* Erste&Steierm\u00e4rkische Ban,<ref>{{cite web |title=Erste Maestro PayPass Display Card |url=https://ceesca.org/uploads/presentations/09-2013/Erste-CEESCA-zadar.pdf |website=Erste Bank |publisher=Erste Bank |access-date=17 July 2021}}</ref> Croatia \n* Getin Bank,<ref>{{cite web |author1=Getin Bank |title=Getin Bank - poznaj now\u0105 Kart\u0119 Display do konta bankowego |url=https://www.youtube.com/watch?v=lek_px4wcXQ |website=YouTube |publisher=YouTube |access-date=17 July 2021 |language=Polish |format=Video |date=June 7, 2013}}</ref> Poland, \n* Newcastle Banking Society,<ref>{{cite news |last1=Grant |first1=Ian |title=Newcastle Banking Society debuts smart display cards |url=https://www.computerweekly.com/news/1280093009/Newcastle-Banking-Society-debuts-smart-display-cards |access-date=17 July 2021 |publisher=Computer Weekly |date=14 Jun 2010}}</ref> UK,  \n* Orange Bank, France, \n* Paypal,<ref>{{cite news |last1=Smith |first1=Josh |title=PayPal security key card - is it worth it? |url=https://www.aol.com/2010/08/04/paypal-security-key-card-offers-extra-security-for-online-paymen/?guccounter=2 |access-date=17 July 2021 |publisher=AOL |date=August 4, 2010}}</ref> USA, \n* Sinopac,<ref>{{cite news |title=Taiwan's Bank SinoPac issues credit cards with digital display |url=https://www.finextra.com/news/fullstory.aspx?newsitemid=21900 |access-date=17 July 2021 |publisher=Finextra |date=14 October 2010}}</ref> Taiwan,  \n* Soci\u00e9t\u00e9 G\u00e9n\u00e9rale,<ref>{{cite news |title=1 Million MOTION CODE? Online Transactions With Soci\u00e9t\u00e9 G\u00e9n\u00e9rale |url=https://www.eleconomista.es/empresas-finanzas/noticias/8679977/10/17/1-Million-MOTION-CODE-Online-Transactions-With-Societe-Generale.html |publisher=El Economista |date=17 October 2017}}</ref> France,  \n* Standard Chartered Bank,<ref>{{cite news |last1=Liau |first1=Yun Qing |title=MasterCard launching banking card with OTP capability |url=https://www.zdnet.com/article/mastercard-launching-banking-card-with-otp-capability/ |agency=ZDNet |publisher=ZDNet |date=November 8, 2012}}</ref><ref>{{cite news |last1=Parrish |first1=Kevin |title=MasterCard Electronic Display Cards Finally Go Mainstream |url=https://www.tomsguide.com/us/MasterCard-Display-Card-Debit-Credit-OTP,news-16282.html |access-date=17 July 2021 |publisher=Tom's Guide |date=November 8, 2012}}</ref>  Singapore,  \n* Symantec,<ref>{{cite news |title=MasterCard, Symantec and NagraID Security team on display card |url=https://www.finextra.com/pressarticle/37871/mastercard-symantec-and-nagraid-security-team-on-display-card |agency=Finextra |publisher=Finextra |date=15 February 2011}}</ref>  \n* TEB,<ref>{{cite news |title=T\u00fcrk Ekonomi Bankas\u0131 (TEB) has launched a new digital banking service |url=https://cardflash.com/news/2015/04/cepteteb/ |access-date=17 July 2021 |publisher=CardFlash |date=27 April 2015}}</ref> Turkey."}},
{"article_title": "Airbag", "pageid": "60023", "revid": "1055882972", "timestamp": "2021-11-18T11:22:38Z", "history_paths": [["Airbag --- Introduction ---", "History"]], "categories": ["airbags", "1973 introductions", "20th-century inventions", "aircraft emergency systems", "american inventions", "bags", "vehicle parts", "vehicle safety technologies"], "heading_tree": {"Airbag --- Introduction ---": {"Active vs. passive safety": {}, "History": {"Origins": {}, "As a substitute to seat belts": {}, "As a supplemental restraint system": {"Frontal airbag": {"Shape of airbags": {}}, "Side airbag": {"Side torso airbag": {}, "Side tubular or curtain airbag": {}}, "Knee airbag": {}, "Tri-Chamber Passenger Airbag": {}, "Rear curtain airbag": {}, "Seat cushion airbag": {}, "Center airbag": {}, "Seat-belt airbag": {}, "Pedestrian airbag": {}, "Manufacturers": {}}}, "Operation": {"Triggering conditions": {"Inflation": {}, "Variable-force deployment": {}, "Post-deployment": {}}}, "Regulatory specifications": {"United States": {}, "Outside the United States": {}}, "Maintenance": {}, "Limitations": {}, "Injuries and fatalities": {"Airbag fatality statistics": {}}, "Aerospace and military applications": {"Spacecraft airbag landing systems": {}, "Aircraft airbag landing systems": {}, "Occupant protection": {}}, "Motorcycle airbag systems": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Airbag --- Introduction ---|History": "[[File:Round & Parrott blue plaque unveiling - Andy Mabbett - 2019-03-18 - 05.jpg|thumb|upright=0.9| [[Blue plaque]] commemorating Round and Parrott's patent, at [[Birmingham Dental Hospital]] ]]\n[[File:Original Airbag Design Blueprint 1953.png|thumb|upright|John W. Hetrick's 1953 safety cushion patent drawing<ref>{{Cite patent|title=Safety cushion assembly for automotive vehicles|pubdate=1953-08-18|country=US|number=2649311|inventor1-first=John W.|inventor1-last=Hetrick|inventor1-link=John_W._Hetrick}}</ref>]]\n[[File:Interior of 1975 Buick Electra.jpg|thumb|1975 [[Buick Electra]] with ACRS]]\n[[File:Ford Mondeon curtain airbag deployed.jpg|thumb|A deployed curtain airbag in a [[Ford Mondeo]]]]\n\n The airbag "for the covering of aeroplane and other vehicle parts" traces its origins to a United States patent, submitted in 1919 by two dentists from [[Birmingham]], Arthur Parrott & Harold Round<ref name="BDH">{{cite web |title=University of Birmingham to unveil new 'blue plaque' celebrating the work of two innovative dentists |url=https://www.birmingham.ac.uk/university/colleges/mds/news/2019/03/dentistry-blue-plaque.aspx |publisher=Birmingham Dental Hospital |access-date=18 March 2019 |date=13 March 2019}}</ref> and approved in 1920.<ref>{{cite patent |country=US |number=1331359 |inventor2-first=Harold |inventor2-last= Round |inventor1-first=Arthur Hughes|inventor1-last= Parrott|pubdate=1920-02-17|assign=[[Robert_Davis_(inventor)|Robert Henry Davis]]}}</ref> Air-filled bladders were in use as early as 1951.<ref>{{cite book|chapter-url= https://books.google.com/books?id=bBDKTa4abNwC&pg=PA12|page=12 |title=Innovative Materials and Techniques in Concrete Construction: ACES Workshop |editor-first=Michael N. |editor-last=Fardis |chapter=1 Non Finito: challenges in rehabilitation |first=Urs |last=Meier |publisher=Springer |year=2012 |isbn=9789400719965 |access-date=16 March 2014}}</ref><ref>{{cite web|title=Air Bags for Automobiles |url= https://textilelearner.net/airbag-for-automobiles/ |work=Textile Learner |first=Moin.S |last=Khan |date= 10 September 2012 |archive-url= https://web.archive.org/web/20121118075037/http://textilelearner.blogspot.com/2012/09/air-bags-for-automobiles-materials-and.html |archive-date=18 November 2012 |access-date=22 September 2016}}</ref> The airbag specifically for automobile use is credited independently to the American John W. Hetrick, who filed for an airbag patent on 5 August 1952, that was granted #2,649,311 by the United States Patent Office on 18 August 1953.<ref>{{cite book|url= https://books.google.com/books?id=kXP6AQAAQBAJ&pg=PA1613|page=1613 |title=Road and Off-Road Vehicle System Dynamics Handbook |year=2014 |publisher=CRC Press |editor-first=Giampiero |editor-last=Mastinu |editor-first2=Manfred |editor-last2=Ploechl |isbn=9780849333224 |access-date=22 September 2016}}</ref><ref>{{cite web|title=United States Patent #2649311|publisher=United States Patent and Trademark Office |url= http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&d=PALL&s1=2649311.PN.|access-date=15 March 2021}}</ref><ref>{{Cite web|title=Patent Images|url=https://pdfpiw.uspto.gov/.piw?Docid=02649311&homeurl=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1%2526Sect2=HITOFF%2526p=1%2526u=/netahtml/PTO/srchnum.html%2526r=1%2526f=G%2526l=50%2526d=PALL%2526s1=2649311.PN.%2526OS=%2526RS=&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|access-date=2021-03-15|website=pdfpiw.uspto.gov}}</ref> German engineer Walter Linderer, who filed German patent #896,312 on 6 October 1951, was issued on 12 November 1953, approximately three months after American John Hetrick. Hetrick and Linderer's airbags were both based on a compressed air system, either released by spring, bumper contact, or by the driver. Later research during the 1960s showed that compressed air could not inflate the mechanical airbags fast enough to ensure maximum safety, leading to the current chemical and electrical airbags.<ref>{{cite web |title=The History of Airbags |date=19 April 2017 |work=The Thought Company |url=https://www.thoughtco.com/history-of-airbags-1991232 |first=Mary |last=Bellis |access-date=22 September 2016 |url-status=dead |archive-url=https://web.archive.org/web/20170714234135/https://www.thoughtco.com/history-of-airbags-1991232 |archive-date=14 July 2017 }}</ref><ref name="Big Ideas">{{cite book|first= Alex |last=Hutchinson |title=Big Ideas: 100 Modern Inventions That Have Transformed Our World |publisher=Sterling Publishing |url= https://books.google.com/books?id=FtN7DIvmmF4C&pg=PA136|page=136 |isbn=9781588167224 |year=2009 |access-date=22 September 2016}}</ref> In patent applications, manufacturers sometimes use the term "inflatable occupant restraint systems".\n\nHetrick was an [[Industrial engineering|industrial engineer]] and member of the [[United States Navy]]. His airbag design, however, only came about when he combined his experiences working with navy [[torpedo]]es with his desire to protect his family on the road. Sadly, despite working with the major automobile manufacturers of his time, no company invested in Hetrick's idea.<ref>{{cite web|url= http://www.airbagsolutions.com/history2.aspx |title=Airbag History \u2013 When Was The Airbag Invented? |publisher=Airbagsolutions.com |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20140316195436/http://www.airbagsolutions.com/history2.aspx |archive-date=16 March 2014}}</ref><ref>{{cite web|url=http://inventors.about.com/od/astartinventions/a/air_bags.htm |title=The History of Airbags |publisher=Inventors.about.com |access-date=16 March 2014}}</ref> Although airbags are now required in every automobile sold in the United States, Hetrick's 1951 patent filing serves as an example of a "valuable" invention with little economic value to its inventor. Its first commercial use was not implemented until after the patent expired in 1971, at which point the airbag was installed in a few experimental [[Ford Motor Company|Ford]] cars.<ref>{{cite book|url= https://books.google.com/books?id=KgCXLF5u9dMC&pg=PA85|page=22.6 |title=Litigation services handbook: the role of the financial expert |editor-first=Roman L. |editor-last=Weil |editor-link1=Roman L. Weil|editor-first2=Peter B. |editor-last2=Frank |editor-first3=Kevin D. |editor-last3=Kreb |publisher=John Wiley |year=2009 |isbn=9780470286609 |access-date=16 March 2014}}</ref>\n\nIn 1964, a Japanese automobile engineer, [[:ja:\u5c0f\u5800\u4fdd\u4e09\u90ce|Yasuzaburou Kobori]] (\u5c0f\u5800\u4fdd\u4e09\u90ce), started developing an airbag "safety net" system. His design harnessed an explosive to inflate an airbag, for which he was later awarded patents in 14 countries. He died in 1975, before seeing widespread adoption of airbag systems.<ref>{{cite web |url= http://www.jahfa.jp/jahfa6/pala/person5-1.htm |title=Achievements of Yasuzaburou Kobori |publisher=Japan Automotive Hall of Fame |language=ja |quote=Source of creative ideas, [he] started the development of the air bag as a starting point to develop a safety net of motor vehicles in 1964. |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20130802085217/http://www.jahfa.jp/jahfa6/pala/person5-1.htm |archive-date=2 August 2013 }}</ref><ref>{{cite web| url= http://zasshi.news.yahoo.co.jp/article?a=20150321-00818815-sspa-soci |title=\u300c\u30a8\u30a2\u30d0\u30c3\u30b0\u300d\u751f\u307f\u306e\u89aa\u306f\u65e5\u672c\u4eba\u3060\u3063\u305f \uff08\u9031\u520aSPA!\uff09|archive-url= https://web.archive.org/web/20150519022006/http://zasshi.news.yahoo.co.jp/article?a=20150321-00818815-sspa-soci |archive-date=19 May 2015 }}</ref><ref>{{cite web |url=http://nikkan-spa.jp/818815/airbag |title=\u30a8\u30a2\u30d0\u30c3\u30b0 - airbag.jpg \u2013 \u65e5\u520aSPA! |author=SPA! |work=\u65e5\u520aSPA! |url-status=dead |archive-url=https://web.archive.org/web/20150323145459/http://nikkan-spa.jp/818815/airbag |archive-date=23 March 2015 |date=21 March 2015 |access-date=13 October 2017 }}</ref>\n\nIn 1967, a breakthrough in the development of airbag crash [[sensor]]s came when Allen K. Breed invented a ball-in-tube mechanism for crash detection. Under his system, an [[Electromechanics|electromechanical]] sensor with a steel ball attached to a tube by a [[magnet]] would inflate an airbag in under 30 milliseconds.<ref>{{cite news|url= https://www.nytimes.com/2000/01/14/business/allen-k-breed-72-a-developer-of-air-bag-technology-for-cars.html |title=Allen K. Breed, 72, a Developer of Air Bag Technology for Cars |first=Nick |last=Ravop |date=14 January 2000 |newspaper=The New York Times |access-date=28 March 2015 |url-status=live |archive-url= https://web.archive.org/web/20150402214752/http://www.nytimes.com/2000/01/14/business/allen-k-breed-72-a-developer-of-air-bag-technology-for-cars.html |archive-date=2 April 2015 }}</ref> A small explosion of [[sodium azide]] was used instead of compressed air during inflation for the first time.<ref name="Big Ideas"/> Breed Corporation then marketed this innovation to [[Chrysler]]. A similar "Auto-Ceptor" crash-restraint, developed by the [[Eaton Corporation|Eaton, Yale & Towne]] company for Ford, was soon also offered as an automatic safety system in the United States,<ref>[http://blog.modernmechanix.com/category/transportation/automotive/page/34/ Popular Science] {{webarchive|url=https://web.archive.org/web/20080229200618/http://blog.modernmechanix.com/category/transportation/automotive/page/34/ |date=29 February 2008}} May 1968</ref><ref>{{cite web|url=http://web.mit.edu/invent/iow/breed.html |title=Inventor of the Week: Archive |publisher=Web.mit.edu |access-date=27 February 2010 |url-status=dead |archive-url= https://web.archive.org/web/20090318103350/http://web.mit.edu/invent/iow/breed.html |archive-date=18 March 2009 }}</ref> while the Italian Eaton-Livia company offered a variant with localized{{elucidate|date=June 2014}} air cushions.<ref name=thetimes>{{cite news|title=Safety Design |first=John |last=Fenton |newspaper=The Times |date=24 January 1969}}</ref>\n\nIn the early 1970s, [[General Motors]] began offering cars equipped with airbags, initially in government [[fleet vehicle|fleet-purchased]], 1973 Chevrolet Impala sedans. These cars came with a 1974-style Oldsmobile instrument panel and a special steering wheel that contained the driver-side air bag. Two of these cars were crash tested after 20 years and the airbags deployed perfectly.<ref>{{cite web |last=Phillips |first=David |title=Impalas' 1973 experimental airbags held up |url= https://www.autonews.com/article/20111031/CHEVY100/310319928/impalas-1973-experimental-airbags-held-up |publisher=Automotive News |date=31 October 2011 |access-date=1 August 2020}}</ref> An early example of the air-bag cars survives as of 2009.<ref>{{cite web |last=Lorio |first=Joe |title=Whats this 73 Chevrolet Impala doing at a classic car auction? |url= https://www.automobilemag.com/news/whats-this-73-chevrolet-impala-doing-at-a-classic-car-auction-2-135242/ |publisher=Automobile Magazine |date=15 June 2009 |access-date=1 August 2020}}</ref> GM's [[Oldsmobile Toronado]] was the first domestic U.S. vehicle to include a passenger airbag.<ref>{{cite news|last1=Phillips|first1=David|title=Impalas' 1973 experimental airbags held up: Fleet customers tested 1,000 vehicles with cutting-edge technology|url= http://www.autonews.com/article/20111031/CHEVY100/310319928/impalas-1973-experimental-airbags-held-up|access-date=16 November 2017|newspaper=Automotive News|date=31 October 2011}}</ref>{{when|date=June 2014}}{{citation needed|date=August 2013}} General Motors marketed its first airbag modules under the "Air Cushion Restraint System" name, or ACRS. The automaker discontinued the option for its 1977 [[model year]], citing lack of consumer interest. Ford and GM then spent years [[lobbying]] against air-bag requirements, claiming that the devices were unfeasible and inappropriate. Chrysler made driver-side airbags standard on 1988\u20131989 models, but airbags did not become widespread in American cars until the early 1990s.<ref>{{cite news|first=Paul |last=Tullis |url= https://www.nytimes.com/packages/html/magazine/2013/innovations-issue/#/?part=airbag |title=Air Bag \u2013 Who Made That? The Magazine's 2013 Innovations Issue |newspaper=The New York Times |date=7 June 2013|url-status=live |archive-url= https://web.archive.org/web/20140215212225/http://www.nytimes.com/packages/html/magazine/2013/innovations-issue/ |archive-date=15 February 2014}}</ref>\n\n Airbags for passenger cars were introduced in the United States in the 1970s, when seat-belt usage rates in the country were quite low compared to modern-day. Ford built experimental cars with airbags in 1971. [[Allstate]] operated a fleet of 200 [[Mercury Monterey]]s and showed reliability of airbags as well as their operation in crash testing, which also was promoted by the insurance company in popular magazine advertisements.<ref>{{cite magazine |title=Allstate fleet cars show the reliability of air bags (advertisement) |magazine=Life |date=9 June 1972 |volume=72 |issue=22 |pages=8\u20139 |url= https://books.google.com/books?id=9lYEAAAAMBAJ&q=Allstate+fleet+cars+show+the+reliability+of+air+bags&pg=PA6 |access-date=13 August 2021}}</ref> General Motors followed in 1973 using full-sized Chevrolet vehicles. The early fleet of experimental GM vehicles equipped with airbags experienced seven fatalities, one of which was later suspected to have been caused by the airbag.<ref>{{cite web |url=http://www.airbagcrash.com/contactusetc.html |title=GM's Acrs |publisher=Airbagcrash.com |year=2001 |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20140223133516/http://www.airbagcrash.com/contactusetc.html |archive-date=23 February 2014 }}</ref>\n\nIn 1974, GM made its ACRS system (which consisted of a padded lower dashboard and a passenger-side air bag) available as a regular production option (RPO code AR3) in full-sized Cadillac,<ref>{{cite web|url= http://www.oldcarbrochures.com/static/NA/Cadillac/1975_Cadillac/1975_Cadillac_Brochure/1975%20Cadillac-25.html |title=1975 Cadillac Brochure |page=25 |publisher=Oldcarbrochures.com |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20140316214731/http://www.oldcarbrochures.com/static/NA/Cadillac/1975_Cadillac/1975_Cadillac_Brochure/1975%20Cadillac-25.html |archive-date=16 March 2014 }}</ref> Buick and Oldsmobile models. The GM cars from the 1970s equipped with ACRS had a driver-side airbag, a driver-side knee restraint,.<ref name="oldcarbrochures1974">{{cite web|url= http://www.oldcarbrochures.com/static/NA/Oldsmobile/1974_Oldsmobile/1974_Oldsmobile_Air_Cushion_Folder/1974%20Oldsmobile%20Air%20Cushion%20Folder-06-07.html |title=1974 Oldsmobile Air Cushion Folder |pages=6\u20137 |publisher=Oldcarbrochures.com |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20141213023724/http://www.oldcarbrochures.com/static/NA/Oldsmobile/1974_Oldsmobile/1974_Oldsmobile_Air_Cushion_Folder/1974%20Oldsmobile%20Air%20Cushion%20Folder-06-07.html |archive-date=13 December 2014 }}</ref> The passenger-side airbag protected both front passengers,<ref name="oldcarbrochures1974"/> and unlike most modern systems, integrated a knee and torso cushion while also having a dual-stage deployment dictated by force of the impact. The cars equipped with ACRS had lap belts for all seating positions, but lacked shoulder belts. Shoulder belts were already mandatory in the United States on closed cars without airbags for the driver and outer front passenger, but GM chose to market its airbags as a substitute for shoulder belts. Prices for this option on Cadillac models were US$225 in 1974, $300 in 1975, and $340 in 1976 (US${{formatnum:{{Inflation|US|340|1976}}}} in {{Inflation-year|US}} dollars {{inflation-fn|US}}).\n\nThe early development of airbags coincided with international interest in automobile safety legislation. Some safety experts advocated a [[Risk assessment|performance-based]] occupant-protection standard rather than one mandating a particular technical solution (which could rapidly become outdated and prove to not be a [[Cost-effectiveness analysis|cost-effective]] approach). Less emphasis was placed on other designs as countries successfully mandated seatbelt restrictions, however.<ref name=thetimes/>\n\n  {{multiple image\n| footer = Three photos of a crash test dummy whose head lands right into the airbag \n| image1 = Airbag1.jpg\n| width1 = 150\n| image2 = Airbag2.jpg\n| width2 = 141 \n| image3 = Airbag3.jpg\n| width3 = 150\n}}\nThe auto industry and research and regulatory communities have moved away from their initial view of the airbag as a seat-belt replacement, and the bags are now nominally designated as supplemental restraint systems ('''SRS''') or supplemental inflatable restraints.\n\nIn 1981, [[Mercedes-Benz]] introduced the airbag in [[West Germany]] as an option on its flagship saloon model, [[Mercedes-Benz W126|S-Class (W126)]]. In the Mercedes system, the sensors automatically tensioned the seat belts to reduce occupants' motion on impact (now a common feature), and then deployed the airbag on impact. This integrated the seat belts and airbag into a restraint system, rather than the airbag being considered an alternative to the seat belt.\n\nIn 1987, the [[Porsche 944]] Turbo became the first car to have driver and passenger airbags as standard equipment.  The Porsche 944 and 944S had this as an available option. The same year also had the first airbag in a Japanese car, the [[Honda Legend]].<ref>{{cite web |url= http://www.jsae.or.jp/autotech/data_e/7-3e.html |title=240 Landmarks of Japanese Automotive Technology \u2013 Subaru Legend airbag system |publisher=Society of Automotive Engineers of Japan |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20141123222600/http://www.jsae.or.jp/autotech/data_e/7-3e.html |archive-date=23 November 2014}}</ref>\n\nIn 1988, [[Chrysler]] became the first United States automaker to fit a driver-side airbag as standard equipment, which was offered in six different models.<ref name="Godshall">{{cite journal|url= https://books.google.com/books?id=duNp3hLLlkUC&pg=PA71|first=Jeffery|last=Godshall |title=Form, Function, and Fantasy \u2013 seventy years of Chrysler design |journal=Automobile Quarterly |volume=32 |issue=4 |pages=70\u201371 |access-date=27 April 2019|isbn=9781596139275}}</ref><ref>{{cite journal|url= http://www.automotive-fleet.com/article/story/1988/07/chrysler-introduces-driver-side-air-bags.aspx |title=Chrysler Introduces Driver-Side Air Bags |date=July 1988 |journal=Automotive Fleet |access-date=27 April 2019 |url-status=live |archive-url= https://web.archive.org/web/20140316195140/http://www.automotive-fleet.com/article/story/1988/07/chrysler-introduces-driver-side-air-bags.aspx |archive-date=16 March 2014 }}</ref> The following year, Chrysler became the first US auto manufacturer to offer driver-side airbags in all its new passenger models.<ref>{{cite web |title=Automobile Safety |url= https://americanhistory.si.edu/america-on-the-move/essays/automobile-safety |publisher=National Museum of American History|date= 24 July 2017 }}</ref><ref>{{cite book|url= https://books.google.com/books?id=K0Le2urkC0cC&pg=PA220|page=220 |title=Business ethics|first=William H. |last=Shaw |publisher=Wadsworth/Cengage |year=2011 |isbn=9780495808763 |access-date=16 March 2014}}</ref> Chrysler also began featuring the air bags in advertisements showing how the devices had saved lives that helped the public know the value of them and safety became a selling advantage in the late 1980s.<ref>{{cite journal |title=1990 Government Mandates Safety |journal=Popular Mechanics |date=May 1996 |volume=173 |issue=5 |page=59 |url= https://books.google.com/books?id=MWUEAAAAMBAJ&pg=PA59 |access-date=5 November 2019}}</ref> All versions of the [[Chrysler minivans (AS)|Chrysler minivans]] came with airbags starting for the 1991 model year.<ref name="Godshall"/> In 1993, The Lincoln Motor Company boasted that all vehicles in their model line were equipped with dual airbags, one for driver-side and another for passenger-side.<ref>https://www.youtube.com/watch?v=wMJSXyTnOhI</ref> The [[Jeep Grand Cherokee (ZJ)|1993 Jeep Grand Cherokee]] became the first SUV to offer a driver-side airbag when it was launched in 1992.<ref>{{cite journal|url= https://books.google.com/books?id=pOMDAAAAMBAJ&pg=PA25|pages=25\u201327 |date=July 1993 |journal=Popular Mechanics |title=Jeep Grand Cherokee \u2013 another home run for the home team |first=Michael |last=Lamm |volume=170 |issue=7 |access-date=16 March 2014}}</ref> Driver and passenger airbags became standard equipment in all [[Dodge Intrepid]], [[Eagle Vision]], and [[Chrysler Concorde]] sedans ahead of any safety regulations.<ref>{{cite book |url= https://books.google.com/books?id=mAZeW0y7h5sC&pg=PA147|page=147 |title=Air Bag Safety: Hearing Before the Committee on Commerce, Science, & Transportation, U.S. Senate |year=1996 |editor-first=Larry |editor-last=Pressler |publisher=Dianne Publishing |access-date=16 March 2014|isbn=9780788170676 }}</ref><ref>Legislation passed in 1991 required driver and front passenger air bags for passenger vehicles offered for sale in the US after September 1997 and for other vehicles after September 1998.{{cite book |title=Air Bag Safety: Hearing Before the Committee on Commerce, Science and Transportations US Senate 104 Congress 2nd session |url= https://books.google.com/books?id=R-bXBSwvBO8C&pg=PA3 |date=2 March 1996 |isbn=9780788170676 |last1=Pressler|first1=Larry}}</ref> Early 1993 saw the 4-millionth airbag-equipped Chrysler vehicle roll off the assembly line.<ref>{{cite press release|url= http://www.thefreelibrary.com/CHRYSLER+AIR+BAG+PRODUCTION+HITS+4+MILLION+UNITS-a013141245 |title=Chrysler air bag production hits 4 million units |date=19 April 1993 |agency=PRNewswire |publisher=thefreelibrary.com |access-date=16 March 2014}}</ref> In October 1993, the [[Dodge Ram]] became the first [[pickup truck]] with a standard driver-side airbag.<ref>{{cite journal|url= https://books.google.com/books?id=5-MDAAAAMBAJ&pg=PA24|page=24 |title=Design and Engineering Awards |journal=Popular Mechanics |date=January 1994 |volume=171 |issue=1 |access-date=16 March 2014}}</ref>\n\nThe first known collision between two airbag-equipped automobiles took place on 12 March 1990 in [[Virginia]], USA. A 1989 [[Chrysler LeBaron]] crossed the [[Road surface marking|center line]] and hit another 1989 Chrysler LeBaron in a [[head-on collision]], causing both driver airbags to deploy. The drivers suffered only minor injuries despite extensive damage to the vehicles.<ref>{{cite news | url = https://pqasb.pqarchiver.com/washingtonpost/doc/307238903.html?FMT=ABS&FMTS=ABS:FT&date=Mar+31%2C+1990&author=Cohn%2C+D%27Vera%3B+Henderson%2C+Nell&pub=The+Washington+Post+%28pre-1997+Fulltext%29&edition=&startpage=a.01&desc=Va.+Crash+Shines+Spotlight+on+Air+Bags%3BSafety+Experts+Say+They+Feel+Vindicated+in+20-Year+Battle |title=Va. Crash Shines Spotlight on Air Bags; Safety Experts Say They Feel Vindicated in 20-Year Battle |date= 31 March 1990 |last1=Cohn |first1=D'Vera |last2=Henderson |first2=Nell |page=A.01 |newspaper=The Washington Post |archive-url= https://web.archive.org/web/20171013172923/https://pqasb.pqarchiver.com/washingtonpost/doc/307238903.html?FMT=ABS&FMTS=ABS:FT&date=Mar+31%2C+1990&author=Cohn%2C+D%27Vera%3B+Henderson%2C+Nell&pub=The+Washington+Post+%28pre-1997+Fulltext%29&edition=&startpage=a.01&desc=Va.+Crash+Shines+Spotlight+on+Air+Bags%3BSafety+Experts+Say+They+Feel+Vindicated+in+20-Year+Battle |archive-date=13 October 2017 |url-status=live |df=dmy-all }}</ref><ref>{{cite news|url= http://articles.orlandosentinel.com/1990-04-01/business/9003312872_1_woody-crash-bags |title=Air Bags Save 2 Lives in Historic Collision |date=1 April 1990 |newspaper=Orlando Sentinel |url-status=live |archive-url= https://web.archive.org/web/20160818150250/http://articles.orlandosentinel.com/1990-04-01/business/9003312872_1_woody-crash-bags |archive-date=18 August 2016 }}</ref><ref>{{citation|url= http://www.people.com/people/archive/article/0,,20117450,00.html |title=Dueling Air Bags Allow Two Virginia Drivers to Walk Away from a Horrifying Head-on Collision |date=23 April 1990 |volume=33 |issue=16 |magazine=[[People (magazine)|People]] |url-status=live |archive-url=https://web.archive.org/web/20160914213704/http://www.people.com/people/archive/article/0%2C%2C20117450%2C00.html |archive-date=14 September 2016 }}</ref>\n\nThe United States [[Intermodal Surface Transportation Efficiency Act]] of 1991 required passenger cars and light trucks built after 1 September 1998 to have airbags for the driver and the right front passenger.<ref name="AirBagTechnology">{{cite web|url=http://www.nhtsa.gov.edgesuite-staging.net/DOT/NHTSA/NRD/Multimedia/PDFs/Crashworthiness/Air%20Bags/rev_report.pdf |page=1 |date=21 June 2001 |title=Air Bag Technology in Light Passenger Vehicles |author=Office of Research and Development |publisher=U.S. NHTSA |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20141215001813/http://www.nhtsa.gov.edgesuite-staging.net/DOT/NHTSA/NRD/Multimedia/PDFs/Crashworthiness/Air%20Bags/rev_report.pdf |archive-date=15 December 2014 }}</ref><ref>{{cite web|url= http://www.history.com/this-day-in-history/federal-legislation-makes-airbags-mandatory |title=Sep 1, 1998: Federal legislation makes airbags mandatory |publisher=history.com |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20140316195048/http://www.history.com/this-day-in-history/federal-legislation-makes-airbags-mandatory |archive-date=16 March 2014 }}</ref> In the United States, NHTSA estimated that airbags had saved over 4,600 lives by 1 September 1999; however, the crash deployment experience of the early 1990s installations indicated that some fatalities and serious injuries were in fact caused by airbags.<ref name="AirBagTechnology"/> In 1998, NHTSA initiated new rules for advanced airbags that gave automakers more flexibility in devising effective technological solutions. The revised rules also required improved protection for occupants of different sizes regardless of whether they use seat belts, while minimizing the risk to infants, children, and other occupants caused by airbags.<ref name="AirBagTechnology"/>\n\nIn [[Europe]], airbags were almost unheard of until the early 1990s. By 1991, four manufacturers \u2013 [[BMW]], [[Honda]], Mercedes-Benz, and [[Volvo]] \u2013 offered the airbag on some of their higher-end models, but shortly afterwards, airbags became a common feature on more mainstream cars, with [[Ford Motor Company|Ford]] and [[Vauxhall Motors|Vauxhall]]/[[Opel]] being among the manufacturers to introduce the airbag to its model ranges in 1992. [[Citro\u00ebn]], [[Fiat]], [[Nissan]], [[Hyundai Motor Group|Hyundai]], [[Peugeot]], [[Renault]], and [[Volkswagen]] followed shortly afterwards.\n\nBy 1999, finding a new mass market car without an airbag at least as optional equipment was difficult, and some late 1990s products, such as the [[Volkswagen Golf Mk4]], also featured side airbags. The [[Peugeot 306]] is one example of the European automotive mass-market evolution: starting in early 1993, most of these models did not even offer a driver's airbag as an option, but by 1999, even side airbags were available on several variants. [[Audi]] was late to offer airbag systems on a broader scale, since even in the 1994 model year, its popular models did not offer airbags. Instead, the German automaker until then relied solely on its proprietary cable-based [[procon-ten]] restraint system.\n\nFrom around 2000, side-impact airbags became commonplace on even low- to mid-range vehicles, such as the smaller-engined versions of the [[Ford Fiesta]] and [[Peugeot 206]], and curtain airbags were also becoming regular features on mass-market cars. The [[Toyota Avensis]], launched in 2003, was the first mass-market car to be sold in Europe with nine airbags.\n\n[[Adaptive airbag|Variable force-deployment]] front airbags were developed to help minimize injury from the airbag itself.\n\nThe emergence of the airbag has contributed to a sharp decline in the number of deaths and serious injuries on the roads of Europe since 1990, and by 2010, the number of cars on European roads lacking an airbag represented a very small percentage of cars, mostly the remaining cars dating from the mid-1990s or earlier.\n\nMany new cars in Latin America, including the [[Kia Picanto]], [[Kia Rio]], [[Hyundai Accent]], and [[Suzuki Alto]], are still regularly sold without airbags, as neither airbags nor [[automatic braking (disambiguation)|automatic braking]] systems in new cars are compulsory in Latin America.\n\n The [[Citro\u00ebn C4]] provided the first "shaped" driver airbag, made possible by this car's unusual fixed-hub steering wheel.<ref>{{cite news|url= http://www.theaustralian.news.com.au/story/0,20867,16128857-13232,00.html |archive-url=https://web.archive.org/web/20060512203054/http://theaustralian.news.com.au/story/0%2C20867%2C16128857-13232%2C00.html |url-status=dead |archive-date=12 May 2006 |title=Citroen C4 |last=Wilson |first=Robert |date=3 August 2005 |newspaper=The Australian |access-date=3 November 2009 }}</ref>\n\n [[File:Seitenairbag Porsche.jpg|thumb|Side airbag inflated permanently for display purposes]]\n[[File:Curtainairbags.JPG|thumb|Deployed curtain airbag and side torso airbag in a [[Citro\u00ebn C4]] ]]\n\nEssentially, two types of side airbags are commonly used today - the side-torso airbag and the side-curtain airbag.\n\nMost vehicles equipped with side-curtain airbags also include side-torso airbags. However, some, such as the [[Chevrolet Cobalt]],<ref>{{cite web |url= http://www.iihs.org/ratings/ratingsbyseries.aspx?id=527 |title=IIHS-HLDI: Chevrolet Cobalt 4-door |publisher=Iihs.org |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20130523132834/http://www.iihs.org/ratings/ratingsbyseries.aspx?id=527 |archive-date=23 May 2013 }}</ref> 2007\u201309 model [[Chevrolet Silverado|Chevrolet Silverado/GMC Sierra]], and 2009\u201312 [[Dodge Ram]]<ref>{{cite web|url= http://www.iihs.org/ratings/rating.aspx?id=1087 |title=IIHS-HLDI: Dodge Ram 1500 |publisher=Iihs.org |date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20100410024807/http://www.iihs.org/ratings/rating.aspx?id=1087 |archive-date=10 April 2010 }}</ref> do not feature the side-torso airbag.\n\n[[Hyundai Motor Group]] announced its development of center side airbag on September 18, 2019. Installed inside the driver\u2019s seat, it is deployed on the instant of detecting impact.\n\n Side-impact airbags or side-torso airbags <!-- (side thorax/abdomen airbags) --> are a category of airbags usually located in the seat<ref>{{cite web |language=en |url= http://www.protext.cz/english/zprava.php?id%3D5890 |title=Johnson Controls develops and manufactures the instrument panel, seating system, door panels and acoustic parking system for the new Mercedes-Benz A-Class |archive-url= https://web.archive.org/web/20170302112307/http://www.protext.cz/english/zprava.php?id=5890 |archive-date=2 March 2017 |access-date=11 May 2018 |url-status=dead}}</ref> or door panel,<ref>{{cite web |language=en |url= http://www.motortrend.com/cars/mercedes-benz/e-class/1996/1996-mercedes-benz-eclass/ |title=1996 Mercedes-Benz E-Class \u2013 Roadtest \u2013 European Car |author=Rik Paul |others=Jerry Garns (photographer) |publisher=MotorTrend |date=1 January 1996 |archive-url= https://web.archive.org/web/20180304003839/http://www.motortrend.com/cars/mercedes-benz/e-class/1996/1996-mercedes-benz-eclass/ |archive-date=4 March 2018 |access-date=11 May 2018 |url-status=live}}</ref> and inflate between the seat occupant and the door. These airbags are designed to reduce the risk of injury to the pelvic and lower abdomen regions.<ref>{{cite web |language=en |url= http://www.freepatentsonline.com/7063350.html |title=Dual chamber side airbag apparatus and method |website=freepatentsonline.com |date=20 June 2006 |access-date=11 May 2018 }}</ref> Most vehicles are now being equipped with different types of designs, to help reduce injury and ejection from the vehicle in rollover crashes. More recent side-airbag designs<ref>{{cite web |language=en |url=http://news.honda.com/newsandviews/article.aspx?id%3D4110-en |title=2008 Honda Accord \u2013 Safety |publisher=American Honda Motor Co. |date=21 August 2007 |archive-url= https://web.archive.org/web/20170302030917/http://news.honda.com/newsandviews/article.aspx?id=4110-en |archive-date=2 March 2017 |access-date=11 May 2018 |url-status=dead}}</ref> include a two chamber system;<ref>{{cite web |language=en |url= https://www.media.volvocars.com/us/en-us/media/pressreleases/3549 |title=All New Volvo S80: Style, Sophistication, Safety and Scandinavian |publisher=Volvo Car Corporation |date=28 February 2006 |archive-url=https://web.archive.org/web/20170302111856/https://www.media.volvocars.com/us/en-us/media/pressreleases/3549 |archive-date=2 March 2017 |access-date=1 March 2017 |url-status=live}}</ref> a firmer lower chamber for the pelvic region and softer upper chamber for the ribcage.<ref>{{cite web |language=en |url=http://xc60volvo.blogspot.de/2009/05/dual-chamber-side-airbags.html |title=Dual-chamber Side Airbags |date=23 October 2009 |archive-url= https://web.archive.org/web/20170202101456/http://xc60volvo.blogspot.de/2009/05/dual-chamber-side-airbags.html |archive-date=2 February 2017 |access-date=26 January 2017 |url-status=live}}</ref><ref>{{Cite journal |language=en |last1=Jakobsson |first1=Lotta |last2=Lindman |first2=Magdalena |last3=Svanberg |first3=Bo |last4=Carlsson |first4=Henrik |title=Real World Data Driven Evolution of Volvo Cars' Side Impact Protection Systems and their Effectiveness |journal=Annals of Advances in Automotive Medicine / Annual Scientific Conference |volume=54 |pages=127\u2013136 |issn=1943-2461 |pmc=3242537 |pmid=21050597 |year=2010}}</ref>\n\nSwedish company [[Autoliv|Autoliv AB]] was granted a patent on side-impact airbags, and they were first offered as an option in 1994<ref name="volvogroup.com">{{cite press release|url= http://www.volvogroup.com/group/global/en-gb/newsmedia/pressreleases/previous/1998/_layouts/CWP.Internet.VolvoCom/NewsItem.aspx?News.ItemId%3D22963%26News.Language%3Den-gb |title=Second-Generation Sips-Bag protects both chest and head |publisher=Volvo Car Corporation |date=17 July 1998 |archive-url= https://web.archive.org/web/20150630101018/http://www.volvogroup.com/group/global/en-gb/newsmedia/pressreleases/previous/1998/_layouts/CWP.Internet.VolvoCom/NewsItem.aspx?News.ItemId=22963&News.Language=en-gb |archive-date=30 June 2015 |access-date=15 January 2020 |url-status=dead}}</ref> on the 1995 [[Volvo 850]], and as standard equipment on all Volvo cars made after 1995.<ref name="volvogroup.com" />\nIn 1997, Saab introduced the first combined head and torso airbags with the launch of the Saab 9-5.\n\nSome cars, such as the 2010 [[Volkswagen Polo Mk5|Volkswagen Polo Mk.5]] have combined head- and torso-side airbags. These are fitted in the backrest of the front seats, and protect the head and the torso.\n\n In 1997, the [[BMW 7 Series (E38)|BMW 7 Series]] and [[BMW 5 Series (E39)|5 Series]] were fitted with tubular-shaped head side airbags (inflatable tubular structure),<ref>{{cite web |url= http://www.zodiacautomotive.com/products/side-impact-rollover-protection/inflatable-tubular-structure-its/ |title=Zodiac Coating \u2013 Medical Silicone Gel Components |work=zodiacautomotive.com |archive-url= https://web.archive.org/web/20150109083508/http://www.zodiacautomotive.com/products/side-impact-rollover-protection/inflatable-tubular-structure-its/ |archive-date=9 January 2015 |access-date=3 September 2018 |url-status=dead}}</ref> the "Head Protection System (HPS)" as standard equipment.<ref>{{cite press release |url= http://www.theautochannel.com/news/press/date/19971030/press007605.html |title=BMW Head Protection System Sets New Standard in Side-Impact Protection in Latest IIHS Crash Test |author=BMW of North America |publisher=Theautochannel.com |date=30 October 1997 |archive-url= https://web.archive.org/web/20140316215210/http://www.theautochannel.com/news/press/date/19971030/press007605.html |archive-date=16 March 2014 |access-date=16 March 2014 |url-status=live}}</ref> This airbag was designed to offer head protection in side impact collisions and also maintained inflation for up to seven seconds for rollover protection. However, this tubular-shaped airbag design has been quickly replaced by an inflatable 'curtain' airbag.\n\nIn May 1998, Toyota began offering a side-curtain airbag deploying from the roof on the [[Toyota Progr\u00e8s|Progr\u00e9s]].<ref>{{cite web |url= http://www.theautochannel.com/news/2007/07/23/055878.html |title=Toyota to Make Side Airbags and Curtain Shield Airbags Standard on All New Passenger Vehicle Models in Japan |publisher=Theautochannel.com |date=23 July 2007 |archive-url= https://web.archive.org/web/20140316215658/http://www.theautochannel.com/news/2007/07/23/055878.html |archive-date=16 March 2014 |access-date=16 March 2014 |url-status=live}}</ref> In 1998, the [[Volvo S80]] was given roof-mounted curtain airbags to protect both front and rear passengers.<ref>{{cite web |language=en |url= https://www.volvoclub.org.uk/press/s80/tech/s80tech3.shtml |title=Volvo S80 |website=www.volvoclub.org.uk |archive-url= https://web.archive.org/web/20160102080537/https://www.volvoclub.org.uk/press/s80/tech/s80tech3.shtml |archive-date=2 January 2016 |access-date=11 May 2018 |url-status=live}}</ref> Curtain airbags were then made standard equipment on all new Volvo cars from 2000 except for the first-generation [[Volvo C70|C70]], which received an enlarged side-torso airbag that also protects the head of front-seat occupants.<ref name="volvogroup.com"/> The second-generation C70 convertible received the world's first door-mounted, side-curtain airbags that deployed upwards.\n\nCurtain airbags have been said to reduce brain injury or fatalities by up to 45% in a side impact with an SUV. These airbags come in various forms (e.g., tubular, curtain, door-mounted) depending on the needs of the application.<ref>{{cite web |url= http://www.safercar.gov/Vehicle+Shoppers/Air+Bags/Side-Impact+Air+Bags+(SABs) |title=Side-Impact Air Bags (SABs) |publisher=Safercar.gov |archive-url= https://web.archive.org/web/20140316214326/http://www.safercar.gov/Vehicle%2BShoppers/Air%2BBags/Side-Impact%2BAir%2BBags%2B%28SABs%29 |archive-date=16 March 2014 |access-date=16 March 2014 |url-status=live}}</ref> Many recent [[Sport utility vehicle|SUVs]] and [[Multi-purpose vehicle|MPVs]] have a long inflatable curtain airbag that protects all rows of seats.\n\nIn many vehicles, the curtain airbags are programmed to deploy during some/all frontal impacts to manage passenger kinetics (e.g. head hitting B-pillar on rebound), especially in offset crashes such as the IIHS's small overlap crash test.\n\n'''Roll-sensing curtain airbag (RSCA)'''\n\nRoll-sensing airbags are different to normal side curtain airbags. They are designed to stay inflated for a longer duration of time, cover a larger proportion of the window, and to be deployed in a roll over crash. They offer protection to occupants' heads and help to prevent ejection. SUVs and pickups are more likely to be equipped with RSCAs due to their higher probability of rolling over and often a switch can disable the feature in case the driver wants to take the vehicle off-road.\n\n The second driver-side and separate knee airbag was used in the [[Kia Sportage]] SUV and has been standard equipment since then. The airbag is located beneath the steering wheel.<ref>{{cite web|url= http://cms.firehouse.com/web/online/University-of-Extrication/Kia-Motors-Knee-Airbag-System/19$708 |archive-url=https://archive.today/20070731071404/http://cms.firehouse.com/web/online/University-of-Extrication/Kia-Motors-Knee-Airbag-System/19$708 |url-status=dead |archive-date=31 July 2007 |title=Kia Motors' Knee Airbag System | Firehouse.com |publisher=Cms.firehouse.com |access-date=8 December 2009 }}</ref><ref>{{cite web|url=https://articles.latimes.com/1996-05-24/business/fi-9924_1_chest-air-bags |title=New Air Bag Will Aim For Knees, Legs |work=Los Angeles Times |url-status=live |archive-url=https://web.archive.org/web/20151208075015/http://articles.latimes.com/1996-05-24/business/fi-9924_1_chest-air-bags |archive-date=8 December 2015 |date=24 May 1996 }}</ref>\n\n[[File:V08589P076.jpg|thumb|Deployed passenger knee airbag in a [[Toyota Tundra]] after a frontal collision test, the driver-side knee airbag also deployed. Blue and yellow markings indicate the dummy's knees.]]\n\nThe [[Toyota Caldina]] introduced the first driver-side SRS knee airbag on the Japanese market in 2002.<ref>{{cite web|url= http://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/electronics_parts/index.html |title=Technical Development: Electronics Parts|work=toyota-global.com |url-status=live |archive-url= https://web.archive.org/web/20150324075624/http://www.toyota-global.com/company/history_of_toyota/75years/data/automotive_business/products_technology/technology_development/electronics_parts/index.html |archive-date=24 March 2015 }}</ref> [[Toyota Avensis]] became the first vehicle sold in Europe equipped with a driver's knee airbag.<ref>{{cite web|url= http://www.toyota.eu/06_Safety/04_implementing_passive_safety/02_airbags.aspx | title=Airbags | website=Toyota Europe|archive-url= https://web.archive.org/web/20090624034121/http://www.toyota.eu/06_Safety/04_implementing_passive_safety/02_airbags.aspx |archive-date=24 June 2009}}</ref><ref>{{cite press release|url= http://www.toyoda-gosei.com/news/2003/030630.html |title=Euro NCAP praises the new Driver-Side SRS Knee Airbag manufactured by Toyoda Gosei |publisher=Toyoda Gosei |date=30 June 2003 |access-date=16 March 2014 |url-status=dead |archive-url= https://web.archive.org/web/20130619041547/http://www.toyoda-gosei.com/news/2003/030630.html |archive-date=19 June 2013 }}</ref> The [[EuroNCAP]] reported on the 2003 Avensis, "There has been much effort to protect the driver's knees and legs and a knee airbag worked well."<ref>{{cite web|url= http://www.euroncap.com/tests/toyota_avensis_2003/172.aspx |title=Toyota Avensis |publisher=Euro NCAP |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20130624135027/http://euroncap.com/tests/toyota_avensis_2003/172.aspx |archive-date=24 June 2013 }}</ref> Since then certain models have also included front-passenger knee airbags, which deploy near or over the [[glove compartment]] in a crash. Knee airbags are designed to reduce leg injury. The knee airbag has become increasingly common from 2000.\n\n \nIn 2019, Honda announced it would introduce a new airbag technology starting in 2021. Developed by Honda R&D in Ohio, U.S.A., this new airbag design features three inflatable chambers connected across the front by a "noninflatable sail panel." The two outer chambers are larger than the middle chamber. When the airbag deploys, the sail panel cushions the occupant's head from the impact of hitting the airbag and the three chambers hold the occupant's head in place like a catcher's mitt.  The goal of the tri-chamber airbag is to help "arrest high speed movement" of the head, thereby reducing the likelihood of concussion injuries in a collision. The first vehicle to come with the tri-chamber airbag installed from the factory was the 2021 Acura TLX. Honda hopes that the new technology will soon make its way to all vehicles.<ref>{{Cite web|url=https://www.caranddriver.com/news/a28791083/honda-multi-compartment-airbag-cars/|title = Honda's New Airbag Will Give Front Passengers Better Protection|date = 23 August 2019}}</ref>\n\n In 2008, the new [[Toyota iQ]] microcar featured the first production rear-curtain shield airbag to protect the rear occupants' heads in the event of a rear-end impact.<ref>{{cite web |last=Abuelsamid |first=Sam |url=http://www.autobloggreen.com/2008/09/30/toyota-develops-rear-curtain-airbag-for-tiny-iq/ |title=Toyota develops rear curtain airbag for tiny iQ |publisher=Autobloggreen.com |date=30 September 2008 |access-date=16 March 2014 |url-status=dead |archive-url=https://web.archive.org/web/20090414062617/http://www.autobloggreen.com/2008/09/30/toyota-develops-rear-curtain-airbag-for-tiny-iq |archive-date=14 April 2009 }}</ref>\n\n Another feature of the Toyota iQ was a seat-cushion airbag in the passenger seat to prevent the pelvis from diving below the lap belt during a frontal impact or submarining.<ref>{{cite web|url= http://www.toyota-global.com/innovation/safety_technology/safety_technology/technology_file/passive/srs_airbag/seat_cushion.html |title=Mobility |access-date=1 March 2017 |url-status=live |archive-url= https://web.archive.org/web/20160225013819/http://www.toyota-global.com/innovation/safety_technology/safety_technology/technology_file/passive/srs_airbag/seat_cushion.html |archive-date=25 February 2016 }}</ref> Later Toyota models such as the Yaris added the feature to the driver's seat, as well.\n\n {{Update|section|date=February 2019}}\n[[File:V08232P024.jpg|thumb|Front-center airbag of a [[Chevrolet Traverse]] deployed in a static out-of-position test: The purpose of the test was to find out how this airbag affects a 3-year-old child who is out of his seat and in the direct reach of the airbag.]]\n[[File:Gurtairbag.jpg|thumb|upright|Seat-belt airbag]]\nIn 2009, Toyota developed the first production rear-seat center airbag designed to reduce the severity of secondary injuries to rear passengers in a side collision. This system deploys from the rear center seat first appearing in on the  [[Toyota Crown Majesta|Crown Majesta]].<ref>{{cite web|url= http://www.worldcarfans.com/109031117798/toyota-develops-worlds-first-rear-seat-center-airbag |title=Toyota Develops World's First Rear-seat Center Airbag |publisher=Worldcarfans.com |date=11 March 2009 |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20140316213508/http://www.worldcarfans.com/109031117798/toyota-develops-worlds-first-rear-seat-center-airbag |archive-date=16 March 2014 }}</ref> In late 2012, General Motors with supplier Takata introduced a front center airbag; it deploys from the driver's seat.<ref>{{cite web|first=Zach |last=Bowman |url= http://www.autoblog.com/2011/09/29/gm-debuts-new-front-center-airbag-w-video/ |title=GM debuts new front center airbag |publisher=Autoblog |date=29 September 2011 |access-date=16 March 2014 |url-status=live |archive-url= https://web.archive.org/web/20140316224521/http://www.autoblog.com/2011/09/29/gm-debuts-new-front-center-airbag-w-video/ |archive-date=16 March 2014 }}</ref>\n\nSome upcoming vehicles in 2020 are equipped with center airbags; [[Polestar 2]],<ref>{{Cite web|title=Polestar Media Newsroom|url=https://www.polestar.com/uk/press/press-release/polestar-2-matches-electric-performance-with-high-levels-of-safety|website=www.polestar.com|access-date=2020-05-30}}</ref> VW [[Volkswagen ID.3|ID.3]].,<ref>{{Cite web|title=New ID.3: 'Today, safety wouldn't be possible without simulation'|url=https://www.volkswagen-newsroom.com:443/en/stories/new-id3-today-safety-wouldnt-be-possible-without-simulation-5429|website=Volkswagen Newsroom|language=en|access-date=2020-05-30}}</ref> Toyota Yaris\n\n The seat-belt airbag is designed to better distribute the forces experienced by a buckled person in a crash by means of increased seat belt area. This is done to reduce possible injuries to the rib cage or chest of the belt wearer.\n*2010: [[Ford Explorer]]<ref name=fbeltairbags>{{cite web |url= https://media.ford.com/content/fordmedia/fna/us/en/news/2013/08/13/ford-expands-availability-of-rear-inflatable-safety-belt-to-2014.html |title=Ford Expands Availability of Rear Inflatable Safety Belt to 2014 Fusion |work=ford.com |archive-url= https://web.archive.org/web/20151006051112/https://media.ford.com/content/fordmedia/fna/us/en/news/2013/08/13/ford-expands-availability-of-rear-inflatable-safety-belt-to-2014.html |archive-date=6 October 2015 |url-status=dead |access-date=17 September 2015}}</ref> and 2013 [[Ford Flex]]: optional rear seat belt airbags; standard on the 2013 [[Lincoln MKT]]\n*2010: [[Lexus LFA]]<ref>{{cite press release |url=http://us.aving.net/news/view.php?articleId=177230 |title=Takata First to Commercialize Front Seat Safety "Airbelt" for Passenger Cars |publisher=us.aving.net/news |date=6 December 2010 |archive-url= https://web.archive.org/web/20140426234136/http://us.aving.net/news/view.php?articleId=177230 |archive-date=26 April 2014 |access-date=11 April 2013 |url-status=live}}</ref> had seat belt airbags for driver and passenger<ref>{{cite web |url =http://www.caranddriver.com/reviews/2012-lexus-lfa-review |title=2012 Lexus LFA |work=caranddriver.com |archive-url= https://web.archive.org/web/20150914203008/http://www.caranddriver.com/reviews/2012-lexus-lfa-review |archive-date=14 September 2015 |url-status=live|date=20 October 2009 }}</ref>\n*2013: [[Mercedes-Benz S-Class (W222)]] has rear seat ''beltbags''<ref>{{cite web |url= http://media.daimler.com/dcmedia/0-921-1549267-1-1549474-1-0-0-1549717-0-1-11702-0-0-1-0-0-0-0-0.html?TS=1419880077161 |title=Extended protection in the rear: The seat belt gets into top shape |work=daimler.com |date=19 November 2012 |archive-url= https://web.archive.org/web/20160102080537/http://media.daimler.com/dcmedia/0-921-1549267-1-1549474-1-0-0-1549717-0-1-11702-0-0-1-0-0-0-0-0.html?TS=1419880077161 |archive-date=2 January 2016 |url-status=dead |access-date=17 September 2015}}</ref>\n*2014: [[Ford Mondeo (fourth generation)|Ford Mondeo Mk IV]]<ref>{{cite web |url= https://media.ford.com/content/fordmedia-mobile/fap/th/en/news/2013/08/13/ford-mondeo-introduces-inflatable-seatbelts--a-ford-first-for-au.html |title=Ford Mondeo Introduces Inflatable Seatbelts, a Ford First for Australian customers |work=ford.com |archive-url= https://web.archive.org/web/20160102080537/https://media.ford.com/content/fordmedia-mobile/fap/th/en/news/2013/08/13/ford-mondeo-introduces-inflatable-seatbelts--a-ford-first-for-au.html |archive-date=2 January 2016 |url-status=dead}}</ref> has optional rear seat belt airbags for the two outer seats<ref>{{cite web |url= http://www.consumerreports.org/cro/news/2011/03/the-ford-inflatable-seat-belt-how-it-affects-car-seats-and-children/index.htm |title=The Ford inflatable seat belt: How it affects car seats and children |work=consumerreports.org |archive-url= https://web.archive.org/web/20150916051302/http://www.consumerreports.org/cro/news/2011/03/the-ford-inflatable-seat-belt-how-it-affects-car-seats-and-children/index.htm |archive-date=16 September 2015 |url-status=live}}</ref>\n\n[[Cessna Aircraft]]<ref>{{cite web|url= http://cessna.txtav.com/citation-service/featured-parts/amsafe-inflatable-seatbelts |title=AmSafe Inflatable Seatbelts |work=Cessna |url-status=live |archive-url= https://web.archive.org/web/20150914023903/http://cessna.txtav.com/citation-service/featured-parts/amsafe-inflatable-seatbelts |archive-date=14 September 2015}}</ref> also introduced seat belt airbags.<ref name = cessnaairbags/> They are as of 2003<ref name=cessnaairbags>{{cite web |url= http://www.flyingmag.com/blogs/fly-wire/are-airbags-worth-money |title=Are Airbags Worth the Money? |work=Flying Magazine |archive-url= https://web.archive.org/web/20160102080538/http://www.flyingmag.com/blogs/fly-wire/are-airbags-worth-money |archive-date=2 January 2016 |url-status=live}}</ref> standard on the 172, 182, and 206.\n\n Airbag(s) mounted to the exterior of vehicles, so called ''pedestrian airbags'', are designed to reduce injuries in the event of a vehicle to pedestrian collision.<ref>{{cite web |language=en |url=http://www-nrd.nhtsa.dot.gov/pdf/esv/esv23/23ESV-000447.PDF |title=Pedestrian Airbag Technology \u2013 a Production System |archive-url= https://web.archive.org/web/20161004224711/http://www-nrd.nhtsa.dot.gov/pdf/esv/esv23/23ESV-000447.PDF |archive-date=4 October 2016 |access-date=4 July 2016 |url-status=dead}}</ref> When a collision is detected the airbag will deploy and cover hard areas, such as a-pillars<ref name=LRDS>{{cite web |url=https://www.youtube.com/watch?v=ZqOJageFVY8 |title=Land Rover Discovery Sport \u2013 Pedestrian Airbag |last=LandRoverMENA |date=1 October 2014 |via=YouTube |archive-url= https://web.archive.org/web/20170602042022/https://www.youtube.com/watch?v=ZqOJageFVY8 |archive-date=2 June 2017 |url-status=live}}</ref> and bonnet edges, before they can be struck by the pedestrian.<ref>{{cite web |url= https://www.youtube.com/watch?v=gauwfbKZAPc |title=YouTube |website=www.youtube.com |archive-url= https://web.archive.org/web/20170602042022/https://www.youtube.com/watch?v=gauwfbKZAPc |archive-date=2 June 2017 |url-status=live}}</ref> \nWhen introduced in 2012 the [[Volvo V40 (P1)|Volvo V40]] included the world's first pedestrian airbag as standard.<ref>{{cite web |language=en |url= http://www.news.com.au/technology/science/volvo-offers-worlds-first-pedestrian-airbag/story-fn5fsgyc-1226579835911 |title=Volvo offers world's first pedestrian airbag |author=Joshua Dowling |date=17 February 2013 |archive-url= https://web.archive.org/web/20141202035414/http://www.news.com.au/technology/science/volvo-offers-worlds-first-pedestrian-airbag/story-fn5fsgyc-1226579835911 |archive-date=2 December 2014 |access-date=5 July 2016 |url-status=live}}</ref> As a result, the V40 ranked highest (88%) in the EuroNCAP's pedestrian tests.<ref>{{cite web |language=en |url= http://www.euroncap.com/results/volvo/v40/485.aspx |title=Volvo V40 |publisher=Euro NCAP |date=August 2013 |archive-url= https://web.archive.org/web/20131015141326/http://www.euroncap.com/results/volvo/v40/485.aspx |archive-date=15 October 2013 |access-date=16 March 2014 |url-status=live}}</ref>\nThe 2014 Land Rover Discovery was fitted with a pedestrian airbag as well.<ref name = LRDS/><ref name=LRDS60>{{cite web |language=en |url= http://www.landrover.com/experiences/news/euro-ncap.html |title=New Discovery Sport Achieves Five Star Euro NCAP Rating |archive-url =https://web.archive.org/web/20160818001413/http://www.landrover.com/experiences/news/euro-ncap.html |archive-date=18 August 2016 |access-date=4 July 2016 |url-status=live}}</ref>\n\n SRS airbag suppliers include [[Autoliv]], [[Daicel]], [[Takata Corporation|Takata]] , [[TRW Automotive|TRW]] and [[Key Safety Systems|KSS]] which is Takata rebadged, formerly Breed, one of the pioneers in the field. The majority of impact sensors of air bags are manufactured by Lanka Harness Company."}},
{"article_title": "Barcode", "pageid": "60600", "revid": "1059844765", "timestamp": "2021-12-12T00:10:40Z", "history_paths": [["Barcode --- Introduction ---", "History"]], "categories": ["barcodes", "encodings", "automatic identification and data capture", "1952 introductions", "american inventions", "records management technology"], "heading_tree": {"Barcode --- Introduction ---": {"History": {"Collins at Sylvania": {}, "Computer Identics Corporation": {}, "Universal Product Code": {}}, "Industrial adoption": {}, "Use": {}, "Symbologies": {}, "Barcode readers": {}, "Quality control and verification": {"Barcode verifier standards": {}}, "Benefits": {}, "Types of barcodes": {"Linear barcodes": {}, "{{anchor|2D barcodes}} Matrix (2D) barcodes": {}, "Example images": {}}, "In popular culture": {}, "Designed barcodes": {}, "Hoaxes about barcodes": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Barcode --- Introduction ---|History": "{{duplication|dupe=Universal Product Code#History|date=December 2013}}\nIn 1948 [[Bernard Silver]], a graduate student at [[Drexel Institute of Technology]] in [[Philadelphia]], Pennsylvania, US overheard the president of the local food chain, [[Food Fair]], asking one of the deans to research a system to automatically read product information during checkout.<ref>{{cite news|date=1 August 2001 |title=The Killer App \u2013 Bar None |url=http://www.americanwaymag.com/so-woodland-bar-code-bernard-silver-drexel-university |first=Charles |last=Fishman |work=American Way |access-date=19 April 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100112043409/http://www.americanwaymag.com/so-woodland-bar-code-bernard-silver-drexel-university |archive-date=12 January 2010  }}</ref> Silver told his friend [[Norman Joseph Woodland]] about the request, and they started working on a variety of systems. Their first working system used [[ultraviolet]] ink, but the ink faded too easily and was expensive.<ref name=story>{{Citation |first=Tony |last=Seideman |title=Barcodes Sweep the World |work=Wonders of Modern Technology |url=http://www.bar-code.com/upc/bar_code_history.php |archive-url=https://web.archive.org/web/20161016084435/http://www.bar-code.com/upc/bar_code_history.php|archive-date=16 October 2016|url-status=dead|date=Spring 1993}}</ref>\n\nConvinced that the system was workable with further development, Woodland left Drexel, moved into his father's apartment in Florida, and continued working on the system. His next inspiration came from [[Morse code]], and he formed his first barcode from sand on the beach. "I just extended the dots and dashes downwards and made narrow lines and wide lines out of them."<ref name=story/> To read them, he adapted technology from optical soundtracks in movies, using a 500-watt incandescent light bulb shining through the paper onto an [[RCA935]] [[photomultiplier]] tube (from a movie projector) on the far side. He later decided that the system would work better if it were printed as a circle instead of a line, allowing it to be scanned in any direction.\n\nOn 20 October 1949, Woodland and Silver filed a patent application for "Classifying Apparatus and Method", in which they described both the linear and [[bullseye (target)|bull's eye]] printing patterns, as well as the mechanical and electronic systems needed to read the code. The patent was issued on 7 October 1952 as US Patent 2,612,994.<ref name="patent"/> In 1951, Woodland moved to [[IBM]] and continually tried to interest IBM in developing the system. The company eventually commissioned a report on the idea, which concluded that it was both feasible and interesting, but that processing the resulting information would require equipment that was some time off in the future.\n\nIBM offered to buy the patent, but the offer was not accepted. [[Philco]] purchased the patent in 1962 and then sold it to [[RCA]] sometime later.<ref name="story"/>\n\n During his time as an undergraduate, [[David Jarrett Collins]] worked at the [[Pennsylvania Railroad]] and became aware of the need to automatically identify railroad cars. Immediately after receiving his master's degree from [[Massachusetts Institute of Technology|MIT]] in 1959, he started work at [[Sylvania Electric Products|GTE Sylvania]] and began addressing the problem. He developed a system called ''KarTrak'' using blue and red reflective stripes attached to the side of the cars, encoding a six-digit company identifier and a four-digit car number.<ref name="story"/> Light reflected off the colored stripes was read by [[photomultiplier]] vacuum tubes.<ref>{{cite web | url =https://www.technologyreview.com/s/601032/david-collins-sm-59/ | title =David Collins, SM '59: Making his mark on the world with bar codes | last =Dunn | first =Peter | date =20 October 2015 | website=technologyreview.com | publisher =MIT | access-date =2 December 2019 }}</ref>\n\nThe [[Boston and Maine Railroad]] tested the KarTrak system on their gravel cars in 1961. The tests continued until 1967, when the [[Association of American Railroads]] (AAR) selected it as a standard, [[Automatic Car Identification]], across the entire North American fleet. The installations began on 10 October 1967. However, the [[1970s#Economy|economic downturn]] and rash of bankruptcies in the industry in the early 1970s greatly slowed the rollout, and it was not until 1974 that 95% of the fleet was labeled. To add to its woes, the system was found to be easily fooled by dirt in certain applications, which greatly affected accuracy. The AAR abandoned the system in the late 1970s, and it was not until the mid-1980s that they introduced a similar system, this time based on radio tags.<ref>{{cite journal |last=Graham-White|first=Sean |date=August 1999|title=Do You Know Where Your Boxcar Is?|journal=Trains |volume=59 |issue=8 |pages=48\u201353 }}</ref>\n\nThe railway project had failed, but a [[toll bridge]] in [[New Jersey]] requested a similar system so that it could quickly scan for cars that had purchased a monthly pass. Then the [[United States Postal Service|U.S. Post Office]] requested a system to track trucks entering and leaving their facilities. These applications required special [[retroreflector]] labels. Finally, [[Whiskas|Kal Kan]] asked the Sylvania team for a simpler (and cheaper) version which they could put on cases of pet food for inventory control.\n\n In 1967, with the [[railway]] system maturing, Collins went to management looking for funding for a project to develop a black-and-white version of the code for other industries. They declined, saying that the railway project was large enough, and they saw no need to branch out so quickly.\n\nCollins then quit Sylvania and formed the Computer Identics Corporation.<ref name="story"/> As its first innovations, Computer Identics moved from using incandescent light bulbs in its systems, replacing them with [[helium\u2013neon laser]]s, and incorporated a mirror as well, making it capable of locating a barcode up to several feet in front of the scanner. This made the entire process much simpler and more reliable, and typically enabled these devices to deal with damaged labels, as well, by recognizing and reading the intact portions.\n\nComputer Identics Corporation installed one of its first two scanning systems in the spring of 1969 at a [[General Motors]] (Buick) factory in Flint, Michigan.<ref name="story"/> The system was used to identify a dozen types of transmissions moving on an overhead conveyor from production to shipping. The other scanning system was installed at General Trading Company's distribution center in Carlstadt, New Jersey to direct shipments to the proper loading bay.\n\n {{Main|Universal Product Code}}\n\nIn 1966, the [[National Association of Food Chains]] (NAFC) held a meeting on the idea of automated checkout systems. [[RCA]], who had purchased the rights to the original Woodland patent, attended the meeting and initiated an internal project to develop a system based on the bullseye code. The [[Kroger]] grocery chain volunteered to test it.\n\nIn the mid-1970s, the NAFC established the Ad-Hoc Committee for U.S. Supermarkets on a Uniform Grocery-Product Code to set guidelines for barcode development. In addition, it created a symbol-selection subcommittee to help standardize the approach. In cooperation with consulting firm, [[McKinsey & Co.]], they developed a standardized 11-digit code for identifying products. The committee then sent out a contract tender to develop a [[barcode system]] to print and read the code. The request went to [[Singer Corporation|Singer]], [[National Cash Register]] (NCR), [[Litton Industries]], RCA, [[Pitney-Bowes]], IBM and many others.<ref>{{cite web |first=George |last=Laurer |author-link=George Laurer |url=http://bellsouthpwp.net/l/a/laurergj/UPC/upc_work.html |title=Development of the U.P.C. Symbol |archive-url=https://web.archive.org/web/20080925105745/http://bellsouthpwp.net/l/a/laurergj/UPC/upc_work.html |archive-date=25 September 2008 }}</ref> A wide variety of barcode approaches was studied, including linear codes, RCA's bullseye concentric circle code, [[wikt:starburst|starburst]] patterns and others.\n\nIn the spring of 1971, RCA demonstrated their bullseye code at another industry meeting. IBM executives at the meeting noticed the crowds at the RCA booth and immediately developed their own system. IBM marketing specialist Alec Jablonover remembered that the company still employed Woodland, and he{{who|date=February 2016}} established a new facility in Raleigh-Durham [[Research Triangle Park]] to lead development.\n\nIn July 1972, RCA began an 18-month test in a Kroger store in Cincinnati. Barcodes were printed on small pieces of adhesive paper, and attached by hand by store employees when they were adding price tags. The code proved to have a serious problem; the printers would sometimes smear ink, rendering the code unreadable in most orientations. However, a linear code, like the one being developed by Woodland at IBM, was printed in the direction of the stripes, so extra ink would simply make the code "taller" while remaining readable. So on 3 April 1973, the IBM UPC was selected as the NAFC standard. IBM had designed five versions of UPC symbology for future industry requirements: UPC A, B, C, D, and E.<ref name="Nelson">{{cite book | last = Nelson | first = Benjamin | year = 1997 | title = Punched Cards To Bar Codes: A 200-year journey |publisher=Helmers |location=Peterborough, N.H. |isbn=9780911261127}}</ref>\n\nNCR installed a testbed system at [[Marsh Supermarkets|Marsh's Supermarket]] in [[Troy, Ohio]], near the factory that was producing the equipment. On 26 June 1974, Clyde Dawson pulled a 10-pack of Wrigley's [[Juicy Fruit]] gum out of his basket and it was scanned by Sharon Buchanan at 8:01 am. The pack of gum and the receipt are now on display in the [[Smithsonian Institution]]. It was the first commercial appearance of the UPC.<ref name="Varchaver">{{cite journal | last = Varchaver | first = Nicholas | date = 31 May 2004 | title = Scanning the Globe | journal = [[Fortune (magazine)|Fortune]] | url = https://money.cnn.com/magazines/fortune/fortune_archive/2004/05/31/370719/index.htm | access-date = 27 November 2006 | archive-url= https://web.archive.org/web/20061114065720/https://money.cnn.com/magazines/fortune/fortune_archive/2004/05/31/370719/index.htm| archive-date= 14 November 2006 | url-status= live}}</ref>\n\nIn 1971, an IBM team was assembled for an intensive planning session, threshing out, 12 to 18 hours a day, how the technology would be deployed and operate cohesively across the system, and scheduling a roll-out plan. By 1973, the team were meeting with grocery manufacturers to introduce the symbol that would need to be printed on the packaging or labels of all of their products. There were no cost savings for a grocery to use it, unless at least 70% of the grocery's products had the barcode printed on the product by the manufacturer. IBM projected that 75% would be needed in 1975. Yet, although this was achieved, there were still scanning machines in fewer than 200 grocery stores by 1977.<ref name="Selmeier">{{cite book |title=Spreading the Barcode |last=Selmeier |first=Bill |year=2009 |publisher=Lulu |pages= 26, 214, 236, 238, 244, 245, 236, 238, 244, 245 | isbn=978-0-578-02417-2 }}</ref>\n\nEconomic studies conducted for the grocery industry committee projected over $40 million in savings to the industry from scanning by the mid-1970s. Those numbers were not achieved in that time-frame and some predicted the demise of barcode scanning. The usefulness of the barcode required the adoption of expensive scanners by a critical mass of retailers while manufacturers simultaneously adopted barcode labels. Neither wanted to move first and results were not promising for the first couple of years, with ''Business Week'' proclaiming "The Supermarket Scanner That Failed" in a 1976 article.<ref name="Varchaver" /><ref>{{cite news|url=https://www.nytimes.com/2010/02/28/t-magazine/womens-fashion/28talk-rawsthorn.html?_r=0|title=Scan Artists| work=New York Times|last= Rawsthorn| first= Alice| date= 23 February 2010| access-date= 31 July 2015}}</ref>\n\nOn the other hand, experience with barcode scanning in those stores revealed additional benefits. The detailed sales information acquired by the new systems allowed greater responsiveness to customer habits, needs and preferences. This was reflected in the fact that about 5 weeks after installing barcode scanners, sales in grocery stores typically started climbing and eventually leveled off at a 10\u201312% increase in sales that never dropped off. There was also a 1\u20132% decrease in operating cost for those stores, and this enabled them to lower prices and thereby to increase market share. It was shown in the field that the [[return on investment]] for a barcode scanner was 41.5%. By 1980, 8,000 stores per year were converting.<ref name="Selmeier" />\n\n[[Sims Supermarket]]s were the first location in Australia to use barcodes, starting in 1979.<ref>{{cite web|title=World hails barcode on important birthday|url=http://www.fullyloaded.com.au/news/logistics/1407/world-hails-barcode-on-important-birthday/|website=ATN|date=1 July 2014}}</ref>"}},
{"article_title": "Surveying", "pageid": "60891", "revid": "1057636214", "timestamp": "2021-11-28T20:00:03Z", "history_paths": [["Surveying --- Introduction ---", "History"]], "categories": ["surveying", "ancient egyptian technology", "civil engineering", "egyptian inventions", "land use"], "heading_tree": {"Surveying --- Introduction ---": {"Definition": {}, "History": {"Ancient history": {}, "Modern era": {}, "20th century": {}, "21st century": {}}, "Equipment": {"Hardware": {}, "Software": {}}, "Techniques": {"Distance measurement": {}, "Angle measurement": {}, "Levelling": {}, "Determining position": {}, "Reference networks": {"Datum and coordinate systems": {}}, "Errors and accuracy": {}}, "Types": {"Plane and geodetic surveying": {}}, "Profession": {"Licensing": {}, "Surveying institutions": {}, "Building surveying": {}, "Cadastral surveying": {}, "Noteworthy surveyors": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Surveying --- Introduction ---|History": "{{see also|History of geodesy|History of cadastre|History of cartography|Topographic map#History}}\n\n [[File:Cc&j-fig23--plumb rule.png|upright=0.4|thumb|alt=refer to caption |A plumb rule from the book Cassells' Carpentry and Joinery]]\nSurveying has occurred since humans built the first large structures. In [[ancient Egypt]], a [[rope stretcher]] would use simple geometry to re-establish boundaries after the annual floods of the [[Nile River]]. The almost perfect squareness and north\u2013south orientation of the [[Great Pyramid of Giza]], built c. 2700 BC, affirm the Egyptians' command of surveying. The ''[[Groma surveying|groma]]'' instrument originated in [[Mesopotamia]] (early 1st millennium BC).<ref>{{citation|title=International Symposium on History of Machines and Mechanisms: Proceedings of HMM 2008|author=Hong-Sen Yan & Marco Ceccarelli|publisher=[[Springer Science+Business Media|Springer]]|year=2009|isbn=978-1-4020-9484-2|page=107}}</ref> The prehistoric monument at [[Stonehenge]] (c. 2500 BC) was set out by prehistoric surveyors using peg and rope geometry.<ref>Johnson, Anthony, ''Solving Stonehenge: The New Key to an Ancient Enigma''. (Thames & Hudson, 2008) {{ISBN|978-0-500-05155-9}}</ref>\n\nThe mathematician [[Liu Hui]] described ways of measuring distant objects in his work ''[[Haidao Suanjing]]'' or ''The Sea Island Mathematical Manual'', published in 263 AD.\n\nThe Romans recognized land surveying as a profession. They established the basic measurements under which the Roman Empire was divided, such as a tax register of conquered lands (300 AD).<ref name="Lewis2001">{{cite book|last=Lewis|first=M. J. T.|title=Surveying Instruments of Greece and Rome|url=https://books.google.com/books?id=1Izau5_ihmsC|access-date=30 August 2012|date=23 April 2001|publisher=Cambridge University Press|isbn=9780521792974}}</ref> Roman surveyors were known as ''[[Gromatici]]''.\n\nIn medieval Europe, [[beating the bounds]] maintained the boundaries of a village or parish. This was the practice of gathering a group of residents and walking around the parish or village to establish a communal memory of the boundaries. Young boys were included to ensure the memory lasted as long as possible.\n\nIn England, [[William the Conqueror]] commissioned the [[Domesday Book]] in 1086. It recorded the names of all the land owners, the area of land they owned, the quality of the land, and specific information of the area's content and inhabitants. It did not include maps showing exact locations.\n\n [[File:Table of Surveying, Cyclopaedia, Volume 2.jpg|thumb|left|alt=Printed image of surveying equipment. | Table of Surveying, 1728 ''[[Cyclopaedia, or an Universal Dictionary of Arts and Sciences|Cyclopaedia]]'']]\n\nAbel Foullon described a [[plane table]] in 1551, but it is thought that the instrument was in use earlier as his description is of a developed instrument.\n\n[[Gunter's chain]] was introduced in 1620 by English mathematician [[Edmund Gunter]]. It enabled plots of land to be accurately surveyed and plotted for legal and commercial purposes.\n\n[[Leonard Digges (scientist)|Leonard Digges]] described a [[theodolite]] that measured horizontal angles in his book ''A geometric practice named Pantometria'' (1571). Joshua Habermel ([[Erasmus Habermehl]]) created a theodolite with a compass and tripod in 1576. Johnathon Sission was the first to incorporate a telescope on a theodolite in 1725.<ref name="turner">Turner, Gerard L'E. ''Nineteenth Century Scientific Instruments'', Sotheby Publications, 1983, {{ISBN|0-85667-170-3}}</ref>\n\nIn the 18th century, modern techniques and instruments for surveying began to be used. [[Jesse Ramsden]] introduced the first precision [[theodolite]] in 1787. It was an instrument for measuring [[angle]]s in the horizontal and vertical planes. He created his [[Ramsden theodolite|great theodolite]] using an accurate [[dividing engine]] of his own design. Ramsden's theodolite represented a great step forward in the instrument's accuracy. [[William Gascoigne (scientist)|William Gascoigne]] invented an instrument that used a [[telescope]] with an installed [[crosshair]] as a target device, in 1640. [[James Watt]] developed an optical meter for the measuring of distance in 1771; it measured the [[parallactic angle]] from which the distance to a point could be deduced.\n\nDutch mathematician [[Willebrord Snellius]] (a.k.a. Snel van Royen) introduced the modern systematic use of [[Triangulation (surveying)|triangulation]]. In 1615 he surveyed the distance from [[Alkmaar]] to [[Breda]], approximately {{convert|72|mi}}. He underestimated this distance by 3.5%. The survey was a chain of quadrangles containing 33 triangles in all. Snell showed how planar formulae could be corrected to allow for the curvature of the earth. He also showed how to [[Free stationing|resect]], or calculate, the position of a point inside a triangle using the angles cast between the vertices at the unknown point. These could be measured more accurately than bearings of the vertices, which depended on a compass. His work established the idea of surveying a primary network of control points, and locating subsidiary points inside the primary network later. Between 1733 and 1740, [[Jacques Cassini]] and his son [[C\u00e9sar-Fran\u00e7ois Cassini de Thury|C\u00e9sar]] undertook the first triangulation of France. They included a re-surveying of the [[meridian arc]], leading to the publication in 1745 of the first map of France constructed on rigorous principles. By this time triangulation methods were well established for local map-making.\n\n[[File:1870 Index Chart to GTS India-1.jpg|thumb|alt=Map of triangulation network covering India.| A map of India showing the Great Trigonometrical Survey, produced in 1870]]\n\nIt was only towards the end of the 18th century that detailed triangulation network surveys mapped whole countries. In 1784, a team from General [[William Roy]]'s [[Ordnance Survey]] of Great Britain began the [[Principal Triangulation of Britain]]. The first Ramsden theodolite was built for this survey. The survey was finally completed in 1853. The [[Great Trigonometric Survey]] of India began in 1801. The Indian survey had an enormous scientific impact. It was responsible for one of the first accurate measurements of a section of an arc of longitude, and for measurements of the geodesic anomaly. It named and mapped [[Mount Everest]] and the other Himalayan peaks. Surveying became a professional occupation in high demand at the turn of the 19th century with the onset of the [[Industrial Revolution]]. The profession developed more accurate instruments to aid its work. Industrial infrastructure projects used surveyors to lay out [[canal]]s, roads and rail.\n\nIn the US, the [[Land Ordinance of 1785]] created the [[Public Land Survey System]]. It formed the basis for dividing the western territories into sections to allow the sale of land. The PLSS divided states into township grids which were further divided into sections and fractions of sections.\n\n[[Napoleon]] Bonaparte founded [[continental Europe]]'s first [[cadastre]] in 1808. This gathered data on the number of parcels of land, their value, land usage, and names. This system soon spread around Europe.\n[[File:Camp of surverying party at Russel's Tank, Arizona, on eastern slope of Laja Range, 1,271 miles from Missouri River. (Boston Public Library) (cropped).jpg|thumb|left|A railroad surveying party at Russel's Tank, [[Arizona]] in the 1860s]]\n[[Robert Richard Torrens|Robert Torrens]] introduced the [[Torrens system]] in South Australia in 1858. Torrens intended to simplify land transactions and provide reliable titles via a centralized register of land. The Torrens system was adopted in several other nations of the English-speaking world.\nSurveying became increasingly important with the arrival of railroads in the 1800s. Surveying was necessary so that railroads could plan technologically and financially viable routes.\n\n [[File:Bundesarchiv Bild 183-S12054, Vermessungstruppe bei Fernaufnahmen.jpg|thumb|alt=Soldier standing next to a Telescopic instrument on a tripod. |A German engineer surveying during the [[First World War]], 1918]]\n\nAt the beginning of the century surveyors had improved the older chains and ropes, but still faced the problem of accurate measurement of long distances. [[Trevor Wadley|Dr Trevor Lloyd Wadley]] developed the [[Tellurometer]] during the 1950s. It measures long distances using two microwave transmitter/receivers.<ref>{{cite web|last1=Sturman|first1=Brian|last2=Wright|first2=Alan|title=The History of the Tellurometer|url=http://www.fig.net/pub/fig2008/papers/hs01/hs01_03_sturman_wright_2833.pdf|publisher=International Federation of Surveyors|access-date=20 July 2014}}</ref>\nDuring the late 1950s [[Geodimeter]] introduced [[electronic distance measurement]] (EDM) equipment.<ref>{{cite web|last1=Cheves |first1=Marc |title=Geodimeter-The First Name in EDM |url=http://www.profsurv.com/magazine/article.aspx?i=394 |access-date=20 July 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140310225310/http://www.profsurv.com/magazine/article.aspx?i=394 |archive-date=10 March 2014 }}</ref> EDM units use a multi frequency phase shift of light waves to find a distance.<ref>{{cite web|last1=Mahun|first1=Jerry|title=Electronic Distance Measurement|url=http://jerrymahun.com/library/Distance/a.htm|website=Jerrymahun.com|access-date=20 July 2014|url-status=dead|archive-url=https://web.archive.org/web/20140729013241/http://jerrymahun.com/library/Distance/a.htm|archive-date=29 July 2014}}</ref> These instruments saved the need for days or weeks of chain measurement by measuring between points kilometers apart in one go.\n\nAdvances in electronics allowed miniaturization of EDM. In the 1970s the first instruments combining angle and distance measurement appeared, becoming known as [[total station]]s. Manufacturers added more equipment by degrees, bringing improvements in accuracy and speed of measurement. Major advances include tilt compensators, data recorders, and on-board calculation programs.\n\nThe first satellite positioning system was the [[US Navy]] [[Transit (satellite)|TRANSIT system]]. The first successful launch took place in 1960. The system's main purpose was to provide position information to [[Polaris missile]] submarines. Surveyors found they could use field receivers to determine the location of a point. Sparse satellite cover and large equipment made observations laborious, and inaccurate. The main use was establishing benchmarks in remote locations.\n\nThe US Air Force launched the first prototype satellites of the [[Global Positioning System]] (GPS) in 1978. GPS used a larger constellation of satellites and improved signal transmission to provide more accuracy. Early GPS observations required several hours of observations by a static receiver to reach survey accuracy requirements. Recent improvements to both satellites and receivers allow [[Real Time Kinematic]] (RTK) surveying. RTK surveys get high-accuracy measurements by using a fixed base station and a second roving antenna. The position of the roving antenna can be tracked.\n\n The [[theodolite]], [[total station]], and [[Real Time Kinematic|RTK]] [[Global Positioning System|GPS]] survey remain the primary methods in use.\n\nRemote sensing and satellite imagery continue to improve and become cheaper, allowing more commonplace use. Prominent new technologies include three-dimensional (3D) scanning and use of [[lidar]] for topographical surveys. [[Unmanned aerial vehicle|UAV]] technology along with [[photogrammetry|photogrammetric]] image processing is also appearing."}},
{"article_title": "Spintronics", "pageid": "61220", "revid": "1062670729", "timestamp": "2021-12-29T21:08:51Z", "history_paths": [["Spintronics --- Introduction ---", "History"]], "categories": ["spintronics", "emerging technologies", "theoretical computer science"], "heading_tree": {"Spintronics --- Introduction ---": {"History": {}, "Theory": {}, "Spintronic-logic devices": {"Applications": {}}, "Semiconductor-based spintronic devices": {"Applications": {}, "Storage media": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Spintronics --- Introduction ---|History": "Spintronics emerged from discoveries in the 1980s concerning spin-dependent electron transport phenomena in solid-state devices. This includes the observation of [[Spin polarization|spin-polarized]] electron injection from a ferromagnetic metal to a normal metal by Johnson and Silsbee (1985)<ref>{{Cite journal | last1 = Johnson | first1 = M. | last2 = Silsbee | first2 = R. H. | doi = 10.1103/PhysRevLett.55.1790 | title = Interfacial charge-spin coupling: Injection and detection of spin magnetization in metals | journal = Physical Review Letters | volume = 55 | issue = 17 | pages = 1790\u20131793 | year = 1985 | pmid =  10031924|bibcode = 1985PhRvL..55.1790J }}</ref> and the discovery of [[giant magnetoresistance]] independently by [[Albert Fert]] et al.<ref>{{Cite journal | last1 = Baibich | first1 = M. N. | last2 = Broto | first2 = J. M. | last3 = Fert | first3 = A. | last4 = Nguyen Van Dau | first4 = F. N. | last5 = Petroff | first5 = F. | last6 = Etienne | first6 = P. | last7 = Creuzet | first7 = G. | last8 = Friederich | first8 = A. | last9 = Chazelas | first9 = J. | doi = 10.1103/PhysRevLett.61.2472 | title = Giant Magnetoresistance of (001)Fe/(001)Cr Magnetic Superlattices | journal = Physical Review Letters | volume = 61 | issue = 21 | pages = 2472\u20132475 | year = 1988 | pmid =  10039127|bibcode = 1988PhRvL..61.2472B | url = http://www.lume.ufrgs.br/bitstream/10183/99075/1/000014840.pdf | doi-access = free }}</ref> and [[Peter Gr\u00fcnberg]] et al. (1988).<ref>{{Cite journal | last1 = Binasch | first1 = G. | last2 = Gr\u00fcnberg | first2 = P. | last3 = Saurenbach | first3 = F. | last4 = Zinn | first4 = W. | title = Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange | doi = 10.1103/PhysRevB.39.4828 | journal = Physical Review B | volume = 39 | issue = 7 | pages = 4828\u20134830 | year = 1989 | pmid =  9948867|bibcode = 1989PhRvB..39.4828B | doi-access = free }}</ref> The origin of spintronics can be traced to the ferromagnet/superconductor tunneling experiments pioneered by Meservey and Tedrow and initial experiments on magnetic tunnel junctions by Julliere in the 1970s.<ref>{{Cite journal | last1 = Julliere | first1 = M. | title = Tunneling between ferromagnetic films | doi = 10.1016/0375-9601(75)90174-7 | journal = Physics Letters A | volume = 54 | issue = 3 | pages = 225\u2013226| year = 1975 |bibcode = 1975PhLA...54..225J }}</ref> The use of semiconductors for spintronics began with the theoretical proposal of a spin field-effect-transistor by [[Supriyo Datta|Datta]] and Das in 1990<ref>{{cite journal| doi =  10.1063/1.102730| author =  Datta, S.| author2 =  Das, B.| name-list-style =  amp |title = Electronic analog of the electrooptic modulator|journal = Applied Physics Letters| volume = 56| pages = 665\u2013667|date = 1990|bibcode = 1990ApPhL..56..665D| issue =  7 }}</ref> and of the [[electric dipole spin resonance]] by [[Emmanuel Rashba|Rashba]] in 1960.<ref>E. I. Rashba, Cyclotron and combined resonances in a perpendicular field, Sov. Phys. Solid State  '''2''', 1109 -1122 (1960)</ref>"}},
{"article_title": "Akademgorodok", "pageid": "63067", "revid": "1029416288", "timestamp": "2021-06-19T20:58:50Z", "history_paths": [["Akademgorodok --- Introduction ---", "History"]], "categories": ["science and technology in siberia", "science and technology in the soviet union", "naukograds", "sovetsky district, novosibirsk"], "heading_tree": {"Akademgorodok --- Introduction ---": {"History": {}, "Akademgorodok in the post-Soviet era": {}, "List of research and education facilities in Akademgorodok": {}, "Sightseeing": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Akademgorodok --- Introduction ---|History": "[[File:Akademgorodok House of Scientists.jpg|thumb|right|The House of Scientists is the cultural centre of Akademgorodok]]\n[[File:Akademgorodok Morskoy Prospekt.jpg|thumb|right|Residential houses at [[Morskoy Prospekt, Novosibirsk|Morskoy Avenue]]]]\nThe town was founded in 1957 under the auspices of the [[Russian Academy of Sciences|Academy of Sciences]] of the [[USSR]]. Academician [[Mikhail Lavrentyev|Mikhail Alexeyevich Lavrentyev]], a [[mechanician]] and mathematician, the first Chairman of the [[Siberian Branch of the Russian Academy of Sciences|Siberian Branch of the Soviet Academy of Sciences]], played a prominent role in establishing Akademgorodok. At its peak, Akademgorodok was home to 65,000 scientists and their families, and was a privileged area to live in.<ref name=graun16>{{cite web |url=https://www.theguardian.com/artanddesign/2016/jan/05/silicon-forest-putin-secret-weapon-global-tech-race-siberia-russia |title=Step into Silicon Forest, Putin's secret weapon in the global tech race |newspaper=The Guardian |date= 5 January 2016 |author= Oliver Wainwright |access-date= 5 January 2016}}</ref>\n\nDuring the Soviet period (1961\u20131991), due to the peculiarity of the Soviet economic system, monetary rewards did not always translate into a higher standard of living. To offset this, a special compensation system was devised in Akademgorodok for its residents and leading scientists. For example, residents of Akademgorodok had access to special food ration distribution outlets (''{{transl|ru|stoly zakazov}}'') that provided, most of the time, an access to some basic subsidized foodstuffs, which were not always easily obtainable elsewhere. Scientists who had obtained a doctorate (a post-Ph.D. degree under the Russian system) were rewarded by the authorities with the special food delivery service (''{{transl|ru|doktorskiy zakaz}}''), which provided access to a wider selection of groceries than available to the general population; some of the scientists, despite being eligible, refused it on moral grounds.{{Citation needed|date=July 2008}} Full and corresponding members of the Academy of Sciences had access to still higher level of service (''{{transl|ru|akademicheskiy zakaz}}'') and were eligible to live in [[single-family residence]]s (called "cottages"), considered luxurious by Soviet standards, as most of the population lived in apartments in nine- and four-story multi-apartment buildings.\n\nDuring the early years residents enjoyed great freedom from the rules and restraints of the Soviet Union, with a modernist cultural centre exhibiting works by banned Soviet artists, risqu\u00e9 poetry evenings, and other activities allowed nowhere else. Scientific research in areas dismissed as dangerous pseudoscience in Moscow, such as cybernetics and genetics, flourished. However, freedoms were severely curtailed in the 1970s during the [[Brezhnev]] era.<ref name=graun16/>"}},
{"article_title": "Brake", "pageid": "65423", "revid": "1047693009", "timestamp": "2021-10-02T03:32:50Z", "history_paths": [["Brake --- Introduction ---", "History"]], "categories": ["brakes", "vehicle braking technologies"], "heading_tree": {"Brake --- Introduction ---": {"Background": {}, "Types": {"Frictional": {}, "Pumping": {}, "Electromagnetic": {}}, "Characteristics": {"Foundation components": {}, "Brake boost": {}}, "Noise": {}, "Fires": {}, "Inefficiency": {}, "History": {"Early brake system": {}, "Electronic brake system": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Brake --- Introduction ---|History": "In the 1890s, Wooden block brakes became obsolete when Michelin brothers introduced rubber tires.<ref>{{Cite web|url=https://didyouknowcars.com/the-history-of-brakes/|title = The History of Brakes | Did You Know Cars|date = 28 August 2017}}</ref>\n\nDuring the 1960s, some car manufacturers replaced drum brakes with disc brakes.<ref>{{Cite web|url=https://didyouknowcars.com/the-history-of-brakes/|title = The History of Brakes | Did You Know Cars|date = 28 August 2017}}</ref>\n\n \nIn 1966, the [[Anti-lock braking system|ABS]] was fitted in the [[Jensen FF]] grand tourer.<ref>{{Cite web|url=https://didyouknowcars.com/the-history-of-brakes/|title = The History of Brakes | Did You Know Cars|date = 28 August 2017}}</ref>\n\nIn 1978, Bosch and Mercedes updated their 1936 anti-lock brake system for the [[Mercedes S-Class]]. That ABS is a fully electronic, four-wheel and multi-channel system that later became standard.<ref>{{Cite web|url=https://didyouknowcars.com/the-history-of-brakes/|title = The History of Brakes | Did You Know Cars|date = 28 August 2017}}</ref>\n\nIn 2005, ESC \u2014 which automatically applies the brakes to avoid a loss of steering control \u2014 become compulsory for carriers of dangerous goods without data recorders in the Canadian province of Quebec.<ref>[http://www.mtq.gouv.qc.ca/portal/page/portal/entreprises_en/camionnage/matieres_dangereuses/reglement/reglement_modifiant_reglement_transport_matiere_dangeureuses Roll Stability Control system (RSC)] {{webarchive|url=https://web.archive.org/web/20110716213223/http://www.mtq.gouv.qc.ca/portal/page/portal/entreprises_en/camionnage/matieres_dangereuses/reglement/reglement_modifiant_reglement_transport_matiere_dangeureuses |date=2011-07-16 }}</ref>\n\nSince 2017, numerous [[United Nations Economic Commission for Europe]] (UNECE) countries use ''Brake Assist System'' (BAS) a function of the braking system that deduces an emergency braking event from a characteristic of the driver's brake demand and under such conditions assist the driver to improve barking.<ref>https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2020/ECE-TRANS-WP.29-343-Rev.28-Add.1.pdf</ref>\n\nIn July 2013<ref>https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2020/ECE-TRANS-WP.29-343-Rev.28-Add.1.pdf</ref> UNECE vehicle regulation 131 was enacted. This regulation defines [[Advanced Emergency Braking Systems]] (AEBS) for heavy vehicles to automatically detect a potential forward collision and activate the vehicle braking system.\n\nOn 23 January 2020<ref>https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2020/ECE-TRANS-WP.29-343-Rev.28-Add.1.pdf</ref> UNECE vehicle regulation 152 was enacted, defining Advanced Emergency Braking Systems for light vehicles.\n\nFrom May 2022, in the European Union, by law, new vehicles will have advanced emergency-braking system.<ref>{{cite web|url=https://www.europarl.europa.eu/news/en/press-room/20190410IPR37528/parliament-approves-eu-rules-requiring-life-saving-technologies-in-vehicles |title=Parliament approves EU rules requiring life-saving technologies in vehicles | News | European Parliament |publisher=Europarl.europa.eu |date=2019-04-16 |access-date=2020-08-31}}</ref>"}},
{"article_title": "Cassette tape", "pageid": "65880", "revid": "1061930073", "timestamp": "2021-12-25T00:01:27Z", "history_paths": [["Cassette tape --- Introduction ---", "History"]], "categories": ["audiovisual introductions in 1963", "audio storage", "tape recording", "computer storage tape media", "home computer peripherals", "philips products", "belgian inventions", "dutch inventions", "1963 in music", "1963 in technology", "computer-related introductions in 1963", "products introduced in 1963", "20th-century inventions", "science and technology in the netherlands", "science and technology in belgium"], "heading_tree": {"Cassette tape --- Introduction ---": {"History": {"Before the Compact Cassette": {}, "Introduction of the Compact Cassette": {}, "Popularity of music cassettes": {}, "Cassette culture": {}, "Decline": {}, "21st-century use and revival": {}}, "Features": {"Cassette types": {}, "Tape length": {}, "Track width": {}, "Head gap": {}, "Write-protection": {}, "Tape leaders": {}, "Endless loop cassette": {}, "Cassette tape adapter": {}, "Optional mechanics": {}, "Flaws": {}}, "Cassette players and recorders": {}, "Applications": {"Audio": {}, "Broadcasting": {}, "Home studio": {}, "Home dubbing": {}, "Institutional duplication": {}, "Data recording {{anchor|data}}": {}, "Video": {}}, "Rivals and successors": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cassette tape --- Introduction ---|History": "{{multiple image\n | width = 260\n | align = right\n | direction = vertical\n | image1 = Wollensak portable reel-to-reel tape recorder.jpg\n | caption1 = Wollensak portable reel-to-reel tape recorder\n | image2 = RCA Quarter Inch Tape Cartridge 2A.png\n | caption2 = Compact Cassette vs. RCA Tape Cartridge\n}}\n\nIn 1935, [[AEG]] released the first [[reel-to-reel tape recorder]] with the commercial name "[[Magnetophon]]". It was based on the invention of the [[magnetic tape]] by [[Fritz Pfleumer]] in 1928. These machines were very expensive and relatively difficult to use and were therefore used mostly by professionals in [[radio station]]s and [[recording studio]]s.\n\nAfter the [[World War II|Second World War]], the magnetic tape recording technology proliferated across the world. In the US, [[Ampex]], using equipment obtained in Germany as a starting point, began commercial production of tape recorders. First used in studios to record radio programs, tape recorders quickly found their way into schools and homes. By 1953, 1 million US homes had tape machines.<ref name=Vartape>{{cite magazine|magazine=[[Variety (magazine)|Variety]]|title=Brew Disk-To-Tape Revolution|date=16 September 1953|page=1|url=http://www.archive.org/stream/variety191-1953-09#page/n144/mode/1up|access-date=6 October 2019}}</ref>\n\nIn 1958, following four years of development, [[RCA Victor]] introduced the stereo, quarter-inch, reversible, reel-to-reel [[RCA tape cartridge]].<ref>{{cite web|url=http://www.videointerchange.com/audio_history.htm |title=videointerchange.com |publisher=videointerchange.com |date=7 August 2010 |access-date=20 August 2010}}</ref><ref>{{cite web|url=http://blog.dianaschnuth.com/details/audio/cartridge.html |title=dianaschnuth.com |publisher=Blog.dianaschnuth.com |access-date=20 August 2010}}</ref> The cartridge was large (5 \u00d7 7 in, or 13 \u00d7 20 cm), and few pre-recorded tapes were offered. Despite the multiple versions, it failed.\n\nConsumer use of magnetic tape machines took off in the early 1960s, after playback machines reached a comfortable, user-friendly design. This was aided by the introduction of [[transistor]]s which replaced the bulky, fragile, and costly [[vacuum tube]]s of earlier designs. Reel-to-reel tape then became more suitable for household use, but still remained an esoteric product.\n\n {{multiple image\n | width = 260\n | align = right\n | direction = vertical\n | image1 = Norelco_Cartridge_Tape_Carry-Corder_150_User_Manual_cover_page.jpg\n | caption1 = Operating instructions for the Philips/Norelco Cartridge Tape Carry-Corder 150 (1964)\n | image2 = Philips EL3302.jpg\n | caption2 = One of the first cassette recorders from Philips, the Typ EL 3302 (1968)\n | image3 = Memorex Compact Cassette opened.jpg\n | caption3 = Inside of a cassette.\n}}\n\nIn the early 1960s Philips Eindhoven tasked two different teams to design a tape cartridge for thinner and narrower tape compared to what was used in reel-to-reel tape recorders. By 1962, the Vienna division of Philips developed a [[single-hole cassette]], adapted from its German described name ''Einloch-Kassette''.<ref>{{Cite book |url=https://books.google.com/books?id=7eA7AAAAMAAJ|title=Radio Elektronik Schau|year=1965|volume=41|language=de}}</ref> The Belgian team created a two-spool cartridge similar to an earlier RCA design, but much smaller.\n\nPhilips selected the two-spool cartridge as a winner and introduced it in Europe on 30 August 1963 at the [[Internationale Funkausstellung Berlin|Berlin Radio Show]],{{refn|<ref>Daniel et al, p.102-4.</ref><ref>David Morton, ''Sound recording: the life story of a technology''. Greenwood Publishing Group, 2004, p.161.</ref><ref>John Shepherd, ''Continuum encyclopedia of popular music of the world''. Continuum International Publishing Group, 2003, p.506</ref><ref>{{Cite magazine|date=4 November 1967|title=Cassette Rampage Forecast|magazine=[[Billboard (magazine)|Billboard]]|publisher=Nielsen Business Media, Inc.|volume=79|issue=44|pages=1, 72|issn=0006-2510}}</ref><ref name="bb8467">{{Cite magazine|date=8 April 1967|title=European Mfrs. Bid for Market Share|magazine=Billboard |publisher=Nielsen Business Media, Inc.|volume=79|issue=14|page=18|issn=0006-2510}}</ref><ref>Jan Drees, Christian Vorbau, ''Kassettendeck: Soundtrack einer Generation''. Klappenbroschur, 2011{{Cite book|date=23 May 2011|title=Kassettendeck: Soundtrack einer Generation|isbn=978-3821866147|last1=Drees|first1=Jan|last2=Vorbau|first2=Christian}}</ref><ref name="Cassette Tape" />}} and in the United States (under the ''[[Norelco]]'' brand) in November 1964. The [[trademark]] name ''Compact Cassette'' came a year later. The team of Dutch and Belgian origin at Philips was led by the Dutch [[Lou Ottens]] in [[Hasselt]], Belgium.<ref>{{cite news|last=Rothman|first=Lily|title=Rewound: On its 50th birthday, the cassette tape is still rolling|url=http://www.time.com/time/magazine/article/0,9171,2148631,00.html|archive-url=https://web.archive.org/web/20130802030310/http://www.time.com/time/magazine/article/0,9171,2148631,00.html|url-status=dead|archive-date=2 August 2013|magazine=[[Time (magazine)|Time]]|access-date=6 August 2013}}</ref><ref>{{cite web|title=Gouden jubileum muziekcassette |url=http://nos.nl/artikel/546117-gouden-jubileum-muziekcassette.html|work=NOS|access-date=30 December 2013}}</ref><ref>{{cite news |url=https://www.theregister.co.uk/2013/09/02/compact_cassette_supremo_lou_ottens_talks_to_el_reg/?page=1 |title=Compact Cassette supremo Lou Ottens talks to El Reg |date=2 September 2013 |access-date=9 April 2020}}</ref>\n\nPhilips also offered a machine to play and record the cassettes, the Philips ''Typ EL 3300''. An updated model, ''Typ EL 3301'' was offered in the US in November 1964 as [[Norelco]] ''Carry-Corder 150''. By 1966 over 250,000 recorders had been sold in the US alone and Japan soon became the major source of recorders. By 1968, 85 manufacturers had sold over 2.4 million players.<ref name="Cassette Tape" /><ref>Hans-Joachim Braun, ''Music and technology in the twentieth century''. JHU Press, 2002, p.161.</ref> By the end of the 1960s, the cassette business was worth an estimated 150 million dollars.<ref name="Cassette Tape" /> By the early 1970s the compact cassette machines were outselling other types of tape machines by a large margin.<ref>{{cite book|title=The Dolby stretcher \u2014 new boon for tape|url=https://worldradiohistory.com/Archive-All-Audio/Archive-Tape-Recording/60s/Tape-Recording-1970-11-12.pdf|publisher=Tape Recording ##11-12, 1970|page=11}}</ref>\n\nPhilips was competing with [[Telefunken]] and [[Grundig]] (with their DC International format <ref>{{Cite web|url=https://thegreatbear.net/audio-tape/grundig-c100/|title = Grundig C 100 and the early history of the Compact Cassette|date = 7 March 2016}}</ref>) in a race to establish its cassette tape as the worldwide standard, and it wanted support from Japanese electronics manufacturers.<ref>{{cite book|last1=Nathan|first1=John|title=Sony: The Private Life|url=https://archive.org/details/sony00john|url-access=registration|date=1999|publisher=Houghton Mifflin|page=[https://archive.org/details/sony00john/page/129 129]}}</ref> Philips' Compact Cassette became dominant as a result of [[Sony]] pressuring Philips to [[license]] the format to them free of charge.<ref>{{cite book|last1=Nathan|first1=John|title=Sony: the Private Life|date=1999|publisher=Houghton Mifflin|page=129|url=https://books.google.com/books?id=6XZ11jJPKQQC&q=philips+company+cassette+free+licensing&pg=PA129|access-date=8 November 2015|isbn=978-0618126941}}</ref>\n\nIn the early years sound quality was mediocre, but it improved dramatically by the early 1970s when it caught up with the quality of [[8-track tape]] and kept improving.<ref name= Daniel /> The Compact Cassette went on to become a popular (and [[Sound recording and reproduction|re-recordable]]) alternative to the [[gramophone record|12-inch vinyl LP]] during the late 1970s.<ref name= Daniel />\n\n The mass production of "blank" (not yet recorded) Compact Cassettes began in 1964 in [[Hanover]], Germany.<ref name="Cassette Tape" /> Prerecorded '''music cassettes''' (also known as ''Music-Cassettes'', and later just '''Musicassettes'''; M.C. for short) were launched in Europe in late 1965. The [[Mercury Record Company]], a US affiliate of Philips, introduced M.C. to the US in July 1966. The initial offering consisted of 49 titles.<ref>{{Cite magazine|date=16 July 1966|title=Mercury Issues 49 'Cassettes'|magazine=Billboard |publisher=Nielsen Business Media, Inc.|volume=78|issue=29|page=69|issn=0006-2510}}</ref>\n\nHowever, the system had been designed initially for dictation and portable use, with the audio quality of early players not well suited for music. Some early models also had an unreliable mechanical design. In 1971, the [[Henry Kloss|Advent Corporation]] introduced their Model 201 tape deck that combined [[Dolby noise-reduction system|Dolby type B]] noise reduction and [[chromium(IV) oxide]] (CrO<sub>2</sub>) tape, with a commercial-grade tape transport mechanism supplied by the Wollensak camera division of 3M Corporation. This resulted in the format being taken more seriously for musical use, and started the era of [[high fidelity]] cassettes and players.<ref name=Camras />\n\nAlthough the birth and growth of the cassette began in the 1960s, its cultural moment took place during the 1970s and 1980s.<ref name="Cassette Tape" /> The cassette's popularity grew during these years as a result of being a more effective, convenient and portable way of listening to music.<ref name="Cassette Tape">{{cite book|last1=Millard|first1=Andre|chapter=Cassette Tape|date=2013|title=[[St. James Encyclopedia of Popular Culture]]|page=529|edition=2.1}}</ref> Stereo tape decks and [[boom box]]es became some of the most highly sought-after consumer products of both decades.<ref name="Cassette Tape"/> Portable pocket recorders and high-fidelity ("hi-fi") players, such as Sony's [[Walkman]] (1979), also enabled users to take their music with them anywhere with ease.<ref name="Cassette Tape"/> The increasing user-friendliness of the cassette led to its popularity around the globe.<ref name="Cassette Tape" /><ref>{{Cite journal|title = Digital Compact Cassette|date = 1994 |volume = 82|issue = 10|pages = 1479\u20131489|journal= [[Proceedings of the IEEE]]|last = Hoogendoorn|first = A|doi = 10.1109/5.326405}}</ref>\n\n[[File:Original Sony Walkman TPS-L2.JPG|thumb|upright|left|The [[Sony Walkman]]]]\nLike the [[transistor radio]] in the 1950s and 1960s, the [[portable CD player]] in the 1990s, and the [[MP3 player]] in the 2000s, the Walkman defined the portable music market for the decade of the '80s, with cassette sales overtaking those of [[gramophone record|LPs]].<ref name="Daniel"/><ref name = Walkman/> Total [[Gramophone record|vinyl record]] sales remained higher well into the 1980s due to greater sales of singles, although [[cassette single]]s achieved popularity for a period in the 1990s.<ref name=Walkman>{{Cite book|title=Doing Cultural Studies: The Story of the Sony Walkman|author1=Paul du Gay |author2=Stuart Hall |author3=Linda Janes |author4=Hugh Mackay |author5=Keith Negus |year=1997|publisher=Sage Publications Ltd|isbn= 978-0-7619-5402-6}}</ref> Another barrier to cassettes overtaking vinyl in sales was [[shoplifting]]; compact cassettes were small enough that a thief could easily place one inside a pocket and walk out of a shop without being noticed. To prevent this, retailers in the US would place cassettes inside oversized "spaghetti box" containers or locked [[display case]]s, either of which would significantly inhibit browsing, thus reducing cassette sales.<ref name="Record8">{{cite journal|last=Gans|first=David |title=Packaging Innovations Raise Cassettes' In-store Profile|journal=Record|date=June 1983|volume=2 |issue=8|page=20}}</ref> During the early 1980s some record labels sought to solve this problem by introducing new, larger packages for cassettes which would allow them to be displayed alongside vinyl records and [[compact disc]]s, or giving them a further market advantage over vinyl by adding [[bonus track]]s.<ref name="Record8"/> Willem Andriessen wrote that the development in technology allowed "hardware designers to discover and satisfy one of the collective desires of human beings all over the world, independent of region, climate, religion, culture, race, sex, age and education: the desire to enjoy music at any time, at any place, in any desired sound quality and almost at any wanted price".<ref>{{cite journal |last=Andriessen|first=Willem|title="THE WINNER": Compact Cassette. A Commercial and Technological Look Back at the Greatest Success Story in the History of Audio Up to Now|journal=[[Journal of Magnetism and Magnetic Materials]]|date=1999|volume=193|issue=1\u20133|pages=12 |doi=10.1016/s0304-8853(98)00502-2}}</ref> Critic [[Robert Palmer (writer)|Robert Palmer]], writing in ''[[The New York Times]]'' in 1981, cited the proliferation of personal stereos as well as extra tracks not available on LP as reasons for the surge in popularity of cassettes.<ref>{{cite news |last1=Palmer |first1=Robert |author1-link=Robert Palmer (writer) |title=The Pop Life; Cassettes Now Have Material Not Available On Disks |url=https://www.nytimes.com/1981/07/29/arts/the-pop-life-cassettes-now-have-material-not-available-on-disks.html?searchResultPosition=9 |access-date=27 April 2021 |work=The New York Times |date=29 July 1981}}</ref>\n\nBetween 1985 and 1992, the cassette tape was the most popular format in the UK and record labels experimented with innovative packaging designs. A designer during the era explained: "There was so much money in the industry at the time, we could try anything with design." The introduction of the [[cassette single]], called a "cassingle", was also part of this era and featured a music single in Compact Cassette form. Until 2005, cassettes remained the dominant medium for purchasing and listening to music in some [[Developing country|developing countries]], but [[compact disc]] (CD) technology had superseded the Compact Cassette in the vast majority of music markets throughout the world by this time.<ref name=BBCthirdworld>{{Cite news|title=Not long left for cassette tapes|publisher=BBC|date=17 June 2005|url=http://news.bbc.co.uk/1/hi/technology/4099904.stm|access-date=13 September 2006}}</ref><ref>{{cite news|title=Total rewind: 10 key moments in the life of the cassette|url=https://www.theguardian.com/music/2013/aug/30/cassette-store-day-music-tapes|access-date=17 March 2014|newspaper=The Guardian|date=30 August 2013|author=Jude Rogers | author-link = Jude Rogers}}</ref>\n\n {{further|Cassette culture}}\nCompact cassettes served as catalysts for social change. Their small size, durability and ease of copying helped bring underground rock and punk music behind the [[Iron Curtain]], creating a foothold for Western culture among the younger generations.<ref>{{Cite book|author=Robin James|title=Cassette Mythos |isbn=978-0-936756-69-1|year=1992|publisher=Autonomedia|location=Brooklyn, NY}}</ref> For similar reasons, cassettes became popular in developing nations.\n\nOne of the most famous political uses of cassette tapes was the dissemination of sermons by the exiled [[Ruhollah Khomeini|Ayatollah Khomeini]] throughout [[Iran]] before the 1979 [[Iranian Revolution]], in which Khomeini urged the overthrow of the regime of the [[Shah]], [[Mohammad Reza Pahlavi]].<ref>{{cite book|page=[https://archive.org/details/assimilatecritic0000reed/page/113 113]|title=Assimilate: A Critical History of Industrial Music|author=S. Alexander Reed|isbn=978-0199832606|year=2013|publisher=Oxford University Press|url=https://archive.org/details/assimilatecritic0000reed/page/113}}</ref> During the [[Military dictatorship of Chile (1973\u20131990)|military dictatorship of Chile]] (1973\u20131990) a "cassette culture" emerged where [[blacklisting|blacklisted]] music or music that was by other reasons not available as records was shared.<ref name=GonzLau19>{{Cite book|title=The SAGE International Encyclopedia of Music and Culture|last=Jord\u00e1n Gonz\u00e1lez|first=Laura|publisher=SAGE Publications|year=2019|isbn=978-1-4833-1775-5|pages=509\u2013511|editor-last=Sturman|editor-first=Janet|chapter=Chile: Modern and Contemporary Performance Practice}}</ref><ref name=Laura2009>{{Cite journal|title=M\u00fasica y clandestinidad en dictadura: la represi\u00f3n, la circulaci\u00f3n de m\u00fasicas de resistencia y el casete clandestino|journal=Revista Musical Chilena|url=https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0716-27902009000200006|last=Jord\u00e1n|first=Laura|year=2009|volume=63|pages=212|issue=Julio-Diciembre|doi=10.4067/S0716-27902009000200006|language=es|trans-title=Music and "clandestinidad" During the Time of the Chilean Dictatorship: Repression and the Circulation of Music of Resistance and Clandestine Cassettes}}</ref><ref name=OmarMarco2017>{{Cite journal|title=Etnograf\u00eda de la m\u00fasica mexicana en Chile: Estudio de caso|journal=Revista Electr\u00f3nica de Divulgaci\u00f3n de la Investigaci\u00f3n|last1=Montoya Arias|first1=Luis Omar|date=12 September 2017|pages=1\u201320|last2=D\u00edaz G\u00fcemez|first2=Marco Aurelio|language=es|volume=14}}</ref> Some [[Copyright infringement|pirate]] cassette producers created brands such as ''Cumbre y Cuatro'' that have in retrospect received praise for their contributions to popular music.<ref name=OmarMarco2017/> [[Armed resistance in Chile (1973\u20131990)|Armed groups]] such as [[Manuel Rodr\u00edguez Patriotic Front]] (FPMR) and the [[Revolutionary Left Movement (Chile)|Revolutionary Left Movement]] (MIR) made use of cassettes to propagandize their struggle.<ref name=Laura2009/>\n\nIn 1970s India, cassettes were blamed for bringing unwanted Christian and Islamic influences into traditionally Sikh and Hindu areas. Cassette technology was a booming market for [[Indian music|pop music in India]], drawing criticism from conservatives while at the same time creating a huge market for legitimate recording companies, as well as pirated tapes.<ref name=Manuel>{{Cite book |author=Peter Manuel |title=Cassette Culture: Popular Music and Technology in North India |publisher=University of Chicago Press |year=1993 |isbn=978-0-226-50401-8 |url=https://archive.org/details/cassetteculturep00manu }}</ref> Some sales channels were associated with cassettes: in Spain [[filling station]]s often featured a display selling cassettes.\nWhile offering also mainstream music these cassettes became associated with genres such as [[Gipsy rhumba]], light music and joke tapes that were very popular in the 1970s and 1980s.<ref name="Retina">{{cite news |last1=Arenas |first1=Guillermo |title=Las cintas de casete pasan de la gasolinera a la Biblioteca Nacional |url=https://retina.elpais.com/retina/2019/08/13/tendencias/1565685637_246147.html |newspaper=El Pa\u00eds |access-date=23 May 2020 |language=es |date=16 August 2019}}</ref>\n\n \nCassettes remained popular for specific applications, such as [[car audio]], [[personal stereo]], [[boomboxes]], [[telephone answering machine]]s, [[field recording]], [[home recording]], and [[mixtape]]s well into the 1990s. Cassette players were typically more resistant to shocks than CD players, and their lower fidelity was not considered a serious drawback. With the introduction of [[electronic skip protection]] it became possible to use portable CD players on the go, and automotive CD players became viable.\n\nBy 1993, annual shipments of CD players had reached 5 million, up 21% from the year before; while cassette player shipments had dropped 7% to approximately 3.4 million.<ref>{{cite encyclopedia|title=Record and prerecorded tape stores|encyclopedia=Gale Encyclopedia of American Industries|year=2005|url=http://www.answers.com/topic/record-and-prerecorded-tape-stores|access-date=20 September 2006}}</ref> By the early 2000s, the CD player rapidly replaced the cassette player as the default audio component in the majority of new vehicles in Europe and America.{{citation needed|date=March 2014}}\n\nSales of pre-recorded music cassettes in the US dropped from 442 million in 1990 to 274,000 by 2007.<ref>{{cite magazine|title=Tape Echo: Specialty labels keep cassettes alive |magazine=Billboard |url=http://www.lostsoundtapes.com/files/billboard_magazine.jpg |date=11 October 2008 |url-status=dead |archive-url=https://web.archive.org/web/20090225121218/http://www.lostsoundtapes.com/files/billboard_magazine.jpg |archive-date=25 February 2009 }}</ref> Most of the major US music companies had discontinued production of pre-recorded cassettes by 2003.\n\nFor [[audiobook]]s, the final year that cassettes represented greater than 50% of total market sales was 2002 when they were replaced by CDs as the dominant media.<ref name=apa2004>[http://www.audiopub.org/LinkedFiles/APA_Fact_Sheet.pdf Audio Publishers Association Fact Sheet] {{webarchive |url=https://web.archive.org/web/20101026033037/http://www.audiopub.org/LinkedFiles/APA_Fact_Sheet.pdf |date=26 October 2010 }} (also includes some historical perspective in the 1950s by Marianne Roney)</ref> Many out-of-print titles, such as those published during the cassette's heyday of the 1970s\u20132000s, are only available on the original cassettes.\n\nThe last new car with an available cassette player was a 2010 [[Lexus SC]] 430.<ref>{{Cite news|title = For Car Cassette Decks, Play Time Is Over|url = https://www.nytimes.com/2011/02/06/automobiles/06AUDIO.html|newspaper = The New York Times|date = 4 February 2011|last1 = Williams|first1 = Stephen}}</ref> The same year, Sony stopped the production of personal cassette players.<ref>{{cite web|title=Sony kills the cassette Walkman on the iPod's birthday|url=https://gizmodo.com/sony-kills-the-cassette-walkman-on-the-ipods-birthday-5671670|access-date=19 October 2020}}</ref> In 2011, the [[Oxford English Dictionary]] removed the word "cassette player" from its 12th edition Concise version.<ref>{{cite dictionary| url=http://blog.oxforddictionaries.com/2011/11/reports-of-the-death-of-the-cassette-tape-are-greatly-exaggerated/ | access-date=28 January 2015 | dictionary=Oxford English Dictionary | first=Ammon | last=Shea | title=Reports of the death of the cassette tape are greatly exaggerated | date=10 November 2011 }}</ref> Some media sources mistakenly claimed that the term "cassette tape" was being removed.<ref>{{cite news| url=http://www.huffingtonpost.com/2011/08/22/cassette-tapes-removal-from-dictionary_n_932107.html | work=Huffington Post | first=David | last=Moye | title=Oxford Dictionary Removes 'Cassette Tape,' Gets Sound Lashing From Audiophiles | date=22 August 2011}}</ref>\n\nIn India, music continued to be released on the cassette format due to its low cost until 2009.<ref>Vanita Kohli-Khandekar, ''The Indian Media Business'', 4th ed. New Delhi: Sage India, 2013. 184-90.\n{{ISBN|9788132118015}}\nbooks.google.com/books?id=tRdBDwAAQBAJ&pg=PT184</ref>\n\n [[Image:Burmese music casette tapes, Yangon, Myanmar.jpg|thumb|Burmese music cassette tapes for sale, [[Yangon]], [[Myanmar]].]]\nAlthough [[Audio recorder#Digital recording|portable digital recorders]] are most common today, analog tape remains a desirable option for certain artists and consumers.<ref name="Lynskey">{{Cite news|url=https://www.theguardian.com/music/2010/mar/29/audio-cassette-comeback |location=London |work=The Guardian |first=Dorian |last=Lynskey |title=Return of the audio cassette |date=29 March 2010}}</ref><ref name="Segal">{{Cite journal |last=Segal |first=Dave |date=9 March 2016 |title=Baby, I'm for Reel: Unspooling the Affordable, Accessible Microeconomy of the Cassette Revival |journal=[[The Stranger (newspaper)|The Stranger]] |url=http://www.thestranger.com/music/2016/03/09/23679384/baby-im-for-reel-unspooling-the-affordable-accessible-microeconomy-of-the-cassette-revival |access-date=11 March 2016 }}</ref> Older genres like "[[dansband]]" may favor the format most familiar to their fans.<ref>{{cite web |url=http://www.dansbandsbloggen.se/2006/05/vad-hnder-med-dansbandsutgivningen-nr.html |title=Vad h\u00e4nder med dansbandsutgivningen n\u00e4r Bert s\u00e4ljer? |language=sv |trans-title=What happens to the dance band release when Bert sells? |website=Dansbandsbloggen.se |date=21 May 2006 |access-date=20 August 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100820082718/http://www.dansbandsbloggen.se/2006/05/vad-hnder-med-dansbandsutgivningen-nr.html |archive-date=20 August 2010 }}</ref> Some musicians and DJs in the [[independent music]] community maintain a tradition of using and releasing cassettes due to its low cost and ease of use.<ref name="Lynskey"/><ref name="Segal"/> Underground and [[DIY punk ethic|DIY]] communities release regularly, and sometimes exclusively, on cassette format, particularly in [[experimental music]] circles and to a lesser extent in [[hardcore punk]], [[death metal]], and [[black metal]] circles, out of a fondness for the format. Even among major-label stars, the form has at least one devotee: [[Thurston Moore]] claimed in 2009, "I only listen to cassettes."<ref name="pitchfork.com">{{cite web|url=http://pitchfork.com/features/articles/7764-this-is-not-a-mixtape/ |title=Articles: This Is Not a Mixtape |website=Pitchfork |date=22 February 2010 |access-date=20 August 2010}}</ref> Very few companies (as of 2021) still make cassettes. Among those are National Audio Company, from the US, and Mulann, also known as Recording The Masters, from France.<ref>{{cite web\n |url=https://www.thelocal.fr/20190322/french-firm-opens-factory-making-first-cassettes-since-1990s-after-artists-like-taylor-swift-go-for-retro-tapes \n |title=French firm opens factory making first cassettes since 1990s after artists like Taylor Swift go retro\n |date=March 22, 2019 |access-date= November 22, 2021}}</ref><ref>{{Cite web|url=https://www.news-leader.com/story/news/local/ozarks/2019/04/22/springfield-audiocassettes-business-national-audio-company-cassette-making/3501329002/|title = National Audio Company now has a cassette-making competitor. They're in France}}</ref> They both make their own magnetic tape, which used to be [[outsourcing|outsourced]].\n\nIn 2010, Botswana-based Diamond Studios announced plans<ref>{{cite web|url=http://allafrica.com/stories/201004190264.html|title=Zimbabwe: Diamond Studios to Commission Cassette Plant|first=Ruth|last=Butaumocho|date=19 April 2010|access-date=1 January 2017|via=AllAfrica}}</ref> for establishing a plant to mass-produce cassettes in a bid to combat piracy. It opened in 2011.<ref>{{cite news | first = Robyn | last = Curnow | title = Pause and rewind: Zimbabwe's audio cassette boom | date = 7 June 2011 | url = http://edition.cnn.com/2011/BUSINESS/06/07/cassette.culture.zimbabwe/index.html | work = CNN | access-date = 13 July 2011}}</ref>\n\nIn South Korea, the early English education boom for toddlers encourages a continuous demand for English language cassettes, {{as of|2011|lc=y}}, due to the affordable cost.<ref>{{cite news|first=Yeon-jin (\uc5f0\uc9c4) |last=Choi (\ucd5c) |script-title=ko:\uba78\uc885 \uc911\uc778 \uce74\uc138\ud2b8, \ud55c\uad6d\uc120 '\uc7a5\uc218 \ub9cc\uc138 |date=31 May 2011 |url=http://news.hankooki.com/lpage/economy/201105/h2011053102312221540.htm |work=Hankook Ilbo |access-date=13 July 2011 |language=ko |url-status=dead |archive-url=https://web.archive.org/web/20110814081328/http://news.hankooki.com/lpage/economy/201105/h2011053102312221540.htm |archive-date=14 August 2011 }}</ref>\n\nNational Audio Company in Missouri, the largest of the few remaining manufacturers of audio cassettes in the US, oversaw the mass production of the [[Guardians of the Galaxy (soundtrack)|"Awesome Mix #1"]] cassette from the film ''[[Guardians of the Galaxy (film)|Guardians of the Galaxy]]'' in 2014.<ref>{{Cite web|title = Meet The Owner Of America's Last Awesome Cassette Tape Factory|url = https://www.slantnews.com/story/2015-09-16-meet-the-owner-of-americas-last-awesome-cassette-tape-factory|website=Slant|access-date = 4 June 2017|url-status=dead|archive-url=https://web.archive.org/web/20160419090228/https://www.slantnews.com/story/2015-09-16-meet-the-owner-of-americas-last-awesome-cassette-tape-factory|archive-date=19 April 2016}}</ref>\nThey reported that they had produced more than 10 million tapes in 2014 and that sales were up 20 percent the following year, their best year since they opened in 1969.<ref>{{cite news|title=This Company Is Still Making Audio Cassettes and Sales Are Better Than Ever |url=https://www.bloomberg.com/news/articles/2015-09-01/this-company-is-still-making-audio-cassettes-and-sales-are-better-than-ever |access-date=9 September 2015|author=Jeniece Pettitt|newspaper=Bloomberg.com |date=1 September 2015}}</ref> In 2016, cassette sales in the United States rose by 74% to 129,000.<ref>{{cite magazine|url=http://www.billboard.com/articles/columns/chart-beat/7662572/us-cassette-album-sales-increase-2016-guardians|title=U.S. Cassette Album Sales Increased by 74% in 2016, Led by 'Guardians' Soundtrack|magazine=[[Billboard (magazine)|Billboard]]|date=21 January 2017}}</ref> In 2018, following several years of shortage, National Audio Company began producing their own magnetic tape, becoming the world's first known manufacturer of an all-new tape stock.<ref>{{cite web|title=The world was running out of cassette tape. Now it's being made in Springfield.|url=https://www.news-leader.com/story/news/local/ozarks/2018/01/07/world-running-out-cassette-tape-now-its-being-made-springfield/852739001/|work=Springfield News-Leader|access-date=24 April 2018|date=7 January 2018}}</ref> Mulann, a company which acquired [[Recording Media Group International|Pyral/RMGI]] in 2015 and originates from [[BASF]], also started production of its new cassette tape stock in 2018, basing on reel tape formula.<ref>{{cite web|title=Audio cassettes are produced again!|url=https://www.recordingthemasters.com/2018/10/11/audio-cassettes-are-produced-again/|work=Mulann S.A.|access-date=6 May 2020|date=11 October 2018}}</ref>\n\nIn Japan and South Korea, the pop acts [[Matsuda Seiko]],<ref>{{cite web |url=http://www.cdjapan.co.jp/product/UPSH-89001 |title=Eien no Motto Hate Made / Wakusei ni Naritai [Cassette Tape] [Limited Edition / Type C]|website=CDJapan}}, CD Japan. Retrieved 13 June 2018</ref> [[SHINee]],<ref>{{cite web |url=https://www.yesasia.com/global/shinee-vol-5-1-of-1-cassette-tape-limited-edition/1053520608-0-0-0-en/info.html |title=SHINee Vol. 5 - 1 of 1 (Cassette Tape Limited Edition)}}, YesAsia. Retrieved 13 June 2018</ref> and [[NCT (band)|NCT 127]]<ref>{{cite web |url=http://tower.jp/item/4710517/Chain-%5b%E3%82%B9%E3%83%9E%E3%83%97%E3%83%A9%E4%BB%98%5d%EF%BC%9C%E5%88%9D%E5%9B%9E%E7%94%9F%E7%94%A3%E9%99%90%E5%AE%9A%E7%9B%A4%EF%BC%9E |title=\u3010\u30ab\u30bb\u30c3\u30c8\u30c6\u30fc\u30d7\u3011 Chain \uff3b\u30b9\u30de\u30d7\u30e9\u4ed8\uff3d\uff1c\u521d\u56de\u751f\u7523\u9650\u5b9a\u76e4\uff1e]}}, Tower Records Japan. Retrieved 13 June 2018</ref> have released their recent material on [[Special edition|limited-run]] cassettes.\n\nIn 2016, retail chain [[Urban Outfitters]], which had long sold [[LP record|LPs]], started selling new pre-recorded cassettes (both new and old albums), blank cassettes, and players.<ref>{{cite web |url=http://www.urbanoutfitters.com/urban/catalog/category.jsp?id=MUSIC-CASSETTES#/ |title=Urban Outfitters Web Site}}, Retrieved 30 July 2016</ref>\n\nSince 2016, cassette sales have seen a modest resurgence, with 2016, 2017, and 2018 all showing increases.<ref>{{cite web |url=https://thevinylfactory.com/news/cassette-album-sales-rise-74-2016/ |title=Cassette sales increased by 74% in 2016|date=23 January 2017}} The Vinyl Factory. Retrieved 26 October 2018</ref><ref>{{cite web |url=https://thevinylfactory.com/news/cassette-sales-2017/ |title=Cassette sales grew 35% in 2017|date=5 January 2018}} The Vinyl Factory. Retrieved 26 October 2018</ref><ref>{{cite web |url=https://thevinylfactory.com/news/uk-cassette-sales-grew-90-percent-first-half-2018/ |title=UK cassette sales grew by 90% in first half of 2018|date=26 July 2018}} The Vinyl Factory. Retrieved 26 October 2018</ref>"}},
{"article_title": "Holography", "pageid": "66338", "revid": "1056901593", "timestamp": "2021-11-24T06:59:17Z", "history_paths": [["Holography --- Introduction ---", "Overview and history"]], "categories": ["holography", "british inventions", "emerging technologies", "hungarian inventions", "laser image generation", "photographic techniques", "3d imaging"], "heading_tree": {"Holography --- Introduction ---": {"Overview and history": {}, "How it works": {"Laser": {}, "Apparatus": {}, "Process": {}, "Comparison with photography": {}}, "Physics of holography": {"Plane wavefronts": {}, "Point sources": {}, "Complex objects": {}}, "Applications": {"Art": {}, "Data storage": {}, "Dynamic holography": {}, "Hobbyist use": {}, "Holographic interferometry": {}, "Interferometric microscopy": {}, "Sensors or biosensors": {}, "Security": {}, "Other applications": {"High security registration plates": {}}}, "Non-optical holography": {}, "False holograms": {}, "In fiction": {}, "See also": {}, "References": {}, "Bibliography": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Holography --- Introduction ---|Overview and history": "The [[Magyars|Hungarian]]-[[British people|British]] physicist [[Dennis Gabor]] (in Hungarian: ''G\u00e1bor D\u00e9nes'')<ref>{{cite journal |last1 = Gabor |first1 = Dennis |author-link = Dennis Gabor |year = 1948 |title = A new microscopic principle |journal = Nature |volume = 161 |issue = 4098 |pages = 777\u20138 |doi=10.1038/161777a0 |bibcode = 1948Natur.161..777G |pmid=18860291 |s2cid = 4121017 }}</ref><ref>{{Cite journal |doi = 10.1098/rspa.1949.0075 |first = Dennis |last = Gabor |year = 1949 |title = Microscopy by reconstructed wavefronts |journal = Proceedings of the Royal Society |volume = 197 |pages = 454\u2013487 |issue = 1051 |bibcode = 1949RSPSA.197..454G |s2cid = 123187722 |doi-access = free}}</ref> was awarded the [[Nobel Prize in Physics]] in 1971 "for his invention and development of the holographic method".<ref>{{cite web |url=https://www.nobelprize.org/nobel_prizes/physics/laureates/1971/ |title=The Nobel Prize in Physics 1971 |publisher=Nobelprize.org |access-date=2012-04-21}}</ref>\n\nHis work, done in the late 1940s, was built on pioneering work in the field of X-ray microscopy by other scientists including [[Mieczys\u0142aw Wolfke]] in 1920 and [[William Lawrence Bragg]] in 1939.<ref name="Hariharan 1996">{{cite book |last1=Hariharan |first1=P. |title=Optical Holography |date=1996 |publisher=Cambridge University Press |location=Cambridge |isbn=9780521433488}}</ref> This discovery was an unexpected result of research into improving [[electron microscope]]s at the [[British Thomson-Houston]] Company (BTH)  in [[Rugby, Warwickshire|Rugby]], England, and the company filed a [[patent]] in December 1947 (patent GB685286). The technique as originally invented is still used in [[electron microscopy]], where it is known as [[electron holography]], but optical holography did not really advance until the development of the [[laser]] in 1960. The word ''holography'' comes from the [[Greek language|Greek]] words {{lang|grc|\u1f45\u03bb\u03bf\u03c2}} (''holos''; "whole") and {{lang|grc|\u03b3\u03c1\u03b1\u03c6\u03ae}} (''[[-graphy|graph\u0113]]''; "[[writing]]" or "[[drawing]]").\n\nA hologram is a recording of an interference pattern which can reproduce a 3D [[light field]] using diffraction. The reproduced light field can generate an image which still has the depth, [[parallax]], and other properties of the original scene.<ref>{{Cite web |url=http://holocenter.org/what-is-holography |title=What is Holography? {{!}} holocenter |language=en-US |access-date=2019-09-02}}</ref>  A hologram is a photographic recording of a light field, rather than an [[image]] formed by a [[Lens (optics)|lens]]. The holographic medium, for example the object produced by a holographic process (which may be referred to as a hologram) is usually unintelligible when viewed under [[Diffuse reflection|diffuse ambient light]]. It is an encoding of the light field as an [[Interference (wave propagation)|interference]] pattern of variations in the [[opacity (optics)|opacity]], [[density]], or surface profile of the photographic medium. When suitably lit, the interference pattern [[Diffraction|diffracts]] the light into an accurate reproduction of the original light field, and the objects that were in it exhibit visual [[Depth perception|depth cues]] such as [[parallax]] and [[perspective (visual)|perspective]] that change realistically with the different angles of viewing. That is, the view of the image from different angles represents the subject viewed from similar angles. In this sense, holograms do not have just the illusion of depth but are truly three-dimensional images.\n\n[[File:III-BIBI BEI BOB.jpg|thumb|Horizontal symmetric text, by [[Dieter Jung (artist)|Dieter Jung]]]]\nThe development of the [[laser]] enabled the first practical optical holograms that recorded 3D objects to be made in 1962 by [[Yuri Denisyuk]] in the Soviet Union<ref name="denisyuk">{{Cite journal \n|title = On the reflection of optical properties of an object in a wave field of light scattered by it \n|last = Denisyuk \n|first = Yuri N. \n|author-link = Yuri Denisyuk\n|journal = [[Doklady Akademii Nauk SSSR]] \n|volume = 144\n|pages = 1275\u20131278\n|year = 1962\n|issue = 6\n}}</ref> and by [[Emmett Leith]] and [[Juris Upatnieks]] at the [[University of Michigan]], USA.<ref name="leith">{{Cite journal \n|title = Reconstructed wavefronts and communication theory\n|author = Leith, E.N.\n|author2=Upatnieks, J.\n|journal = J. Opt. Soc. Am. \n|volume = 52\n|pages = 1123\u20131130\n|year = 1962\n|doi =10.1364/JOSA.52.001123| issue = 10\n|bibcode = 1962JOSA...52.1123L\n}}</ref> Early holograms used [[silver halide]] photographic emulsions as the recording medium. They were not very efficient as the produced grating absorbed much of the incident light. Various methods of converting the variation in transmission to a variation in refractive index (known as "bleaching") were developed which enabled much more efficient holograms to be produced.<ref>{{cite journal |last1 = Upatniek |first1 = J |last2 = Leaonard |first2 = C |year = 1969 |title = Diffraction efficiency of bleached photographically recorded intereference patterns |journal = Applied Optics |volume = 8 |issue = 1 |pages = 85\u201389 |doi = 10.1364/ao.8.000085 |pmid = 20072177 |bibcode = 1969ApOpt...8...85U }}</ref><ref>{{cite journal |last1 = Graube |first1 = A |year = 1974 |title = Advances in bleaching methods for photographically recorded holograms |journal = Applied Optics |volume = 13 |issue = 12 |pages = 2942\u20136 |doi = 10.1364/ao.13.002942 |pmid = 20134813 |bibcode = 1974ApOpt..13.2942G }}</ref><ref>{{cite journal |last1 = Phillips |first1 = N. J. |last2 = Porter |first2 = D. |year = 1976 |title = An advance in the processing of holograms |journal = Journal of Physics E: Scientific Instruments |volume = 9 |issue = 8 |page = 631 |doi = 10.1088/0022-3735/9/8/011 |bibcode = 1976JPhE....9..631P }}</ref>\n\nOptical holography needs a [[laser]] light to record the light field. In its early days, holography required high-power and expensive lasers, but currently, mass-produced low-cost [[laser diode]]s, such as those found on [[DVD recorder]]s and used in other common applications, can be used to make holograms and have made holography much more accessible to low-budget researchers, artists and dedicated hobbyists. A [[Microscopic scale|microscopic]] level of detail throughout the recorded scene can be reproduced. The 3d image can, however, be viewed with non-laser light. In common practice, however, major image quality compromises are made to remove the need for laser illumination to view the hologram, and in some cases, to make it. Holographic portraiture often resorts to a non-holographic intermediate imaging procedure, to avoid the dangerous high-powered [[Laser#Pulsed operation|pulsed lasers]] which would be needed to optically "freeze" moving subjects as perfectly as the extremely motion-intolerant holographic recording process requires. Holograms can now also be entirely computer-generated to show objects or scenes that never existed. Most holograms produced are of static objects but systems for displaying changing scenes on a holographic [[volumetric display]] are now being developed.<ref>{{cite web |url=http://www.tgdaily.com/hardware-features/53703-mit-unveils-holographic-tv-system |title=MIT unveils holographic TV system |access-date = 2011-09-14}}</ref><ref>See [[Zebra imaging]].</ref><ref>{{cite journal |last1 = Blanche |first1 = P.-A. |year =2010 |title =  Holographic three-dimensional telepresence using large-area photorefractive polymer |journal = Nature |volume = 468 |issue = 7320 |pages = 80\u201383 |doi=10.1038/nature09521 |last2 = Bablumian |first2 = A. |last3 = Voorakaranam |first3 = R. |last4 = Christenson |first4 = C. |last5 = Lin |first5 = W. |last6 = Gu |first6 = T. |last7 = Flores |first7 = D. |last8 = Wang |first8 = P. |last9 = Hsieh |first9 = W.-Y. |last10 = Kathaperumal |first10 = M. |last11 = Rachwal |first11 = B. |last12 = Siddiqui |first12 = O. |last13 = Thomas |first13 = J. |last14 = Norwood |first14 = R. A. |last15 = Yamamoto |first15 = M. |last16 = Peyghambarian |first16 = N. |pmid = 21048763 |bibcode = 2010Natur.468...80B |s2cid = 205222841 |display-authors = 8 }}</ref>\n\nHolography is distinct from [[lenticular lens|lenticular]] and other earlier [[autostereoscopy|autostereoscopic]] 3D display technologies, which can produce superficially similar results but are based on conventional lens imaging. Images requiring the aid of [[Stereoscopy|special glasses or other intermediate optics]], stage illusions such as [[Pepper's Ghost]] and other unusual, baffling, or seemingly magical images are often incorrectly called holograms.\n\nIt is also distinct from [[specular holography]] which is a technique for making three-dimensional images by controlling the motion of specularities on a two-dimensional surface.<ref>{{cite web |url=http://www.zintaglio.com/how.html |title=specular holography: how |publisher=Zintaglio.com |access-date=2012-04-21}}</ref> It works by reflectively or refractively manipulating bundles of light rays, not by using interference and diffraction.\n\nHolography is also used with many other types of [[Holography#Non-optical holography|waves]]."}},
{"article_title": "Nixie tube", "pageid": "66904", "revid": "1059338925", "timestamp": "2021-12-08T21:59:19Z", "history_paths": [["Nixie tube --- Introduction ---", "History"]], "categories": ["display technology", "neon lighting", "obsolete technologies", "vacuum tube displays"], "heading_tree": {"Nixie tube --- Introduction ---": {"History": {}, "Design": {}, "Applications and lifetime": {}, "Alternatives and successors": {}, "Legacy": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Nixie tube --- Introduction ---|History": "[[File:NixieFrequencyCounter.jpg|thumb|Systron-Donner frequency counter from 1973 with Nixie-tube display]]\n\nThe early Nixie displays were made by a small vacuum tube manufacturer called Haydu Brothers Laboratories, and introduced in 1955<ref>'Solid State Devices--Instruments' article by S. Runyon in ''Electronic Design'' magazine vol. 24, 23 November 1972, p. 102, via Electronic Inventions and Discoveries: Electronics from its Earliest Beginnings to the Present Day, 4th Ed., Geoffrey William Arnold Dummer, 1997, {{ISBN|0-7503-0376-X}}, p. 170</ref> by [[Burroughs Corporation]], who purchased Haydu. The name ''Nixie'' was derived by Burroughs from "NIX I", an abbreviation of "Numeric Indicator eXperimental No. 1",<ref name="sciam">{{cite journal |last1=Sobel |first1=Alan |title=Electronic Numbers |journal=Scientific American |date=June 1973 |volume=228 |issue=6 |pages=64\u201373 |doi=10.1038/scientificamerican0673-64 |jstor=24923073}}</ref> although this may have been a [[backronym]] designed to justify the evocation of [[Nixie (folklore)|the mythical creature with this name]]. Hundreds of variations of this design were manufactured by many firms, from the 1950s until the 1990s. The Burroughs Corporation introduced "Nixie" and owned the name ''Nixie'' as a [[trademark]]. Nixie-like displays made by other firms had trademarked names including ''Digitron'', ''Inditron'' and ''Numicator''. A proper generic term is ''cold cathode neon readout tube'', though the phrase ''Nixie tube'' quickly entered the vernacular as a generic name.\n\nBurroughs even had another Haydu tube that could operate as a [[Counter (digital)|digital counter]] and directly drive a Nixie tube for display. This was called a "Trochotron", in later form known as the "Beam-X Switch" counter tube; another name was "magnetron beam-switching tube", referring to their derivation from a [[magnetron|split-anode magnetron]]. Trochotrons were used in the [[UNIVAC 1101]] computer, as well as in clocks and frequency counters.\n\nThe first trochotrons were surrounded by a hollow cylindrical magnet, with poles at the ends. The field inside the magnet had essentially-parallel lines of force, parallel to the axis of the tube. It was a thermionic vacuum tube; inside were a central cathode, ten anodes, and ten "spade" electrodes. The magnetic field and voltages applied to the electrodes made the electrons form a thick sheet (as in a cavity magnetron) that went to only one anode. Applying a pulse with specified width and voltages to the spades made the sheet advance to the next anode, where it stayed until the next advance pulse. Count direction was determined by the direction of the magnetic field, and as such was not reversible. A later form of trochotron called a Beam-X Switch replaced the large, heavy external cylindrical magnet with ten small internal metal-alloy rod magnets which also served as electrodes.\n\n[[File:In 19a.jpg|thumb|upright|This \u0418\u041d-19\u0410 (IN-19A) Nixie tube displays symbols, including % and \u00b0C.]]\n\nGlow-transfer counting tubes, similar in essential function to the trochotrons, had a glow discharge on one of a number of main cathodes, visible through the top of the glass envelope. Most used a neon-based gas mixture and counted in base-10, but faster types were based on argon, hydrogen, or other gases, and for timekeeping and similar applications a few base-12 types were available. Sets of "guide" cathodes (usually two sets, but some types had one or three) between the indicating cathodes moved the glow in steps to the next main cathode. Types with two or three sets of guide cathodes could count in either direction. A well-known trade name for glow-transfer counter tubes in the [[United Kingdom]] was [[Dekatron]]. Types with connections to each individual indicating cathode, which enabled presetting the tube's state to any value (in contrast to simpler types which could only be directly reset to zero or a small subset of their total number of states), were trade named ''Selectron'' tubes.\n\nDevices that functioned in the same way as Nixie tubes were patented in the 1930s, and the first mass-produced display tubes were introduced in 1954 by National Union Co. under the brand name Inditron. However, their construction was cruder, their average lifetime was shorter, and they failed to find many applications due to their complex periphery."}},
{"article_title": "Satellite radio", "pageid": "67066", "revid": "1062799592", "timestamp": "2021-12-30T16:21:01Z", "history_paths": [["Satellite radio --- Introduction ---", "History and overview"]], "categories": ["satellite radio", "international broadcasting", "digital radio", "radio technology"], "heading_tree": {"Satellite radio --- Introduction ---": {"History and overview": {"Africa and Eurasia": {}, "United States": {}, "Japan": {}, "Canada": {}}, "System design": {}, "Content, availability and market penetration": {}, "Satellite radio vs. other formats": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Satellite radio --- Introduction ---|History and overview": "The first satellite radio broadcasts occurred in Africa and the Middle East in 1999. The first US broadcasts were in 2001 followed by Japan in 2004 and Canada in 2005.\n\nThere have been three (not counting [[MobaHo!]] of Japan) major satellite radio companies: [[WorldSpace]], [[Sirius Satellite Radio]] and [[XM Satellite Radio]], all founded in the 1990s in the United States. WorldSpace operated in the Africa and Asia region, whereas Sirius and XM competed in the North American (USA and Canada) market. Of the three companies, WorldSpace went bankrupt in 2009 and Sirius and XM merged in 2008 to form [[Sirius XM]]. The merger was done to avoid bankruptcy. The new company had financial problems and was within days of bankruptcy in 2009, but was able to find investors. The company did not go bankrupt and Sirius XM Satellite radio continues ({{as of|2021|lc=on}}) to operate.\n\n WorldSpace was founded by Ethiopia-born lawyer Noah Samara in [[Washington, D.C.]], in 1990,<ref>{{cite news |first=Alex |last=Benady |url=https://www.independent.co.uk/news/media/clockwork-meets-satellite-in-a-revolution-for-third-world-radio-1162230.html |title=Clockwork meets satellite in a revolution for Third World radio |work=[[The Independent]] |date=June 1, 1998}}</ref> with the goal of making satellite radio programming available to the developing world.<ref name="dhilzenrath">{{cite news |first=David S. |last=Hilzenrath |url=https://www.washingtonpost.com/wp-dyn/content/article/2010/03/18/AR2010031801762.html |title=WorldSpace announces potential decommissioning of satellites |work=Washington Post |date=March 18, 2010}}</ref> On June 22, 1991, the FCC gave WorldSpace permission to launch a satellite to provide digital programming to [[Africa]] and the [[Middle East]].<ref name="eandrews"/> WorldSpace first began broadcasting satellite radio on October 1, 1999, in Africa.<ref>{{cite news |first=Denise |last=Caruso |url=https://www.nytimes.com/1999/10/11/business/technology-digital-commerce-can-technology-investors-move-into-areas-like-africa.html |title=Digital Commerce |work=New York Times |date=October 11, 1999}}</ref> [[India]] would ultimately account for over 90% of WorldSpace\u2019s subscriber base.<ref>{{cite news |first=Dilip |last=Maitra |url=http://www.deccanherald.com/content/43092/worldspace-india-shut-shop-december.html |title=WorldSpace India to shut shop on December 31 |work=[[Deccan Herald]] |date=December 24, 2009}}</ref> In 2008, WorldSpace announced plans to enter [[Europe]], but those plans were set aside when the company filed for [[Chapter 11, Title 11, United States Code|Chapter 11]] bankruptcy in November 2008.<ref>{{cite news |first=Eric |last=Pfanner |url=https://www.nytimes.com/2009/01/11/business/worldbusiness/11iht-radio.1.19245263.html?pagewanted=all&_r=0 |title=As AM signal fades, Europe moves hesitantly to digital radio |work=New York Times |date=January 11, 2009}}</ref> In March 2010, the company announced it would be de-commissioning its two satellites (one served [[Asia]], the other served Africa). [[Liberty Media]], which owns 50% of Sirius XM Radio, had considered purchasing WorldSpace\u2019s assets, but talks between the companies collapsed.<ref name="dhilzenrath"/><ref>{{cite news |first=Roger |last=Collis |url=https://www.nytimes.com/2002/12/20/style/20iht-trfreq_ed3__.html |title=The Frequent Traveler: Keeping in touch on the road through satellite radio |work=New York Times |date=December 20, 2002}}</ref> The satellites are now transmitting educational data and operate under the name of Yazmi USA, LLC.\n\nOndas Media was a Spanish company which had proposed to launch a subscription-based satellite radio system to serve Spain and much of Western Europe, but failed to acquire licenses throughout Europe.{{citation needed|date=January 2019}}\n\nOnde Num\u00e9rique was a French company which had proposed to launch a subscription-based satellite radio system to serve France and several other countries in Western Europe but has suspended its plans indefinitely, effective December, 2016.{{citation needed|date=January 2019}}\n\n Sirius Satellite Radio was founded by [[Martine Rothblatt]], [[David Margolese]] and [[Robert Briskman]].<ref name="mherper">{{cite news |first=Matthew |last=Herper |url=https://www.forbes.com/forbes/2010/0510/second-acts-pharmaceuticals-orphan-drugs-pah-deep-breaths.html |title=From Satellites to Pharmaceuticals |work=[[Forbes]] |date=April 22, 2010}}</ref><ref name="swarren">{{cite book |first=Steve |last=Warren |url=https://books.google.com/books?id=s0jSxLqs-TwC&q=cd+radio+david+margolese&pg=PT181 |title=Radio: The Book |publisher=[[Focal Press]] |year=2004 |page=166|isbn=9780240806969 }}</ref> In June 1990, Rothblatt's shell company, Satellite CD Radio, Inc., petitioned the [[Federal Communications Commission]] (FCC) to assign new frequencies for satellites to broadcast digital sound to homes and cars.<ref name="eandrews"/> The company identified and argued in favor of the use of the [[S-band]] frequencies that the FCC subsequently decided to allocate to digital audio broadcasting. The [[National Association of Broadcasters]] contended that satellite radio would harm local radio stations.<ref name="lbelsie"/>\n\nIn April 1992, Rothblatt resigned as CEO of Satellite CD Radio;<ref name="mherper"/> former NASA engineer Robert Briskman, who designed the company's satellite technology, was then appointed chairman and CEO.<ref>{{cite news |url=http://www.highbeam.com/doc/1G1-12310541.html |archive-url=https://web.archive.org/web/20131031092005/http://www.highbeam.com/doc/1G1-12310541.html |url-status=dead |archive-date=October 31, 2013 |title=Robert Briskman appointed chairman and CEO |work=Satellite News |date=June 1, 1992}}</ref><ref name="bmclean">{{cite news |first=Bethany |last=McLean |url=https://money.cnn.com/magazines/fortune/fortune_archive/2001/01/22/295563/index.htm |title=Satellite Killed The Radio Star| work=[[Fortune (magazine)|Fortune]] |date=January 22, 2001 |pages=94\u2013100}}</ref> Six months later, [[Rogers Wireless]] co-founder David Margolese, who had provided financial backing for the venture, acquired control of the company and succeeded Briskman. Margolese renamed the company CD Radio, and spent the next five years lobbying the FCC to allow satellite radio to be deployed, and the following five years raising $1.6 billion, which was used to build and launch three satellites into elliptical orbit from [[Kazakhstan]] in July 2000.<ref name="bmclean"/><ref>{{cite news |first=Nancy |last=Dillon |url=http://www.nydailynews.com/archives/money/beaming-radio-high-tech-fast-lane-article-1.875098 |title=Beaming Radio Into High-Tech Fast Lane |work=[[New York Daily News]] |date=June 5, 2000}}</ref><ref>{{cite book |first=Christopher H. |last=Sterling |url=https://books.google.com/books?id=Z4XJQD4O_TkC&q=sirius+name+change+orbital&pg=PA750 |title=Encyclopedia of Radio, Volume 1 |publisher=[[Taylor & Francis]] |year=2003 |page=750|isbn=9780203484289 }}</ref><ref>{{cite news |first=Simon |last=Romero |url=https://www.nytimes.com/2000/07/10/business/xm-satellite-radio-completes-its-financing.html |title=XM Satellite Radio Completes Its Financing |work=New York Times|date=July 10, 2000}}</ref> In 1997, after Margolese had obtained regulatory clearance and "effectively created the industry," the FCC also sold a license to the American Mobile Radio Corporation,<ref>{{cite news |first=Simon |last=Houpt |url=http://www.davidmargolese.com/pub/report-on-business-web.pdf |title=Radio Flyer |work=[[Report on Business]] |issue=September 2001 |pages=14\u201316}}</ref> which changed its name to [[XM Satellite Radio]] in October 1998.<ref>{{cite press release|url=http://nl.newsbank.com/nl-search/we/Archives?p_product=NewsLibrary&p_multi=BBAB&d_place=BBAB&p_theme=newslibrary2&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0F98E7271A1EFA29&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |title=AMRC changes name to XM Satellite Radio |author=XM Satellite Radio |location=New York |publisher=BBC Archive |date=November 16, 1998}}</ref> XM was founded by Lon Levin and [[Gary Parsons]], who served as chairman until November 2009.<ref>{{cite magazine |first=Vince |last=Beiser |url=https://www.wired.com/science/space/magazine/15-11/ff_spacehotel?currentPage=4 |title=Hotel Biz Zillionaire's Next Venture? Inflatable Space Pods |magazine=[[Wired (magazine)|Wired]] |date=October 23, 2007}}</ref><ref>{{cite news |first=Kathy |last=Shwiff |url=https://www.wsj.com/articles/SB10001424052748703683804574532221444468060 |title=Parsons Resigns as Chairman of Sirius XM Radio |work=[[Wall Street Journal]] |date=November 12, 2009}}</ref>\n\nCD Radio purchased their license for $83.3 million, and American Mobile Radio Corporation bought theirs for $89.9 million. Digital Satellite Broadcasting Corporation and [[Primosphere]] were unsuccessful in their bids for licenses.<ref>{{cite news |url=https://www.pbs.org/newshour/media/radio/comparison.html  |title=Revolutions in Radio |work=[[PBS]] Newshour |date=May 4, 2005}}</ref> Sky Highway Radio Corporation had also expressed interest in creating a satellite radio network, before being bought out by CD Radio in 1993 for $2 million.<ref>{{cite web |url=http://www.fundinguniverse.com/company-histories/sirius-satellite-radio-inc-history/ |title=Sirius Satellite Radio, Inc. History |website=fundinguniverse.com |access-date=May 7, 2013}}</ref> In November 1999, Margolese changed the name of CD Radio to Sirius Satellite Radio.<ref name="swarren"/> In November 2001, Margolese stepped down as CEO, remaining as chairman until November 2003, with Sirius issuing a statement thanking him "for his great vision, leadership and dedication in creating both Sirius and the satellite radio industry."<ref>{{cite web |url=http://www.thefreelibrary.com/David+Margolese+Steps+Down+as+Sirius+CEO.-a079162975 |title=David Margolese Steps Down as Sirius CEO |website=[[PRNewswire]] |date=October 16, 2001}}</ref>\n\nXM\u2019s first satellite was launched on March 18, 2001 and its second on May 8, 2001.<ref name="kbonsor">{{cite web |first=Kevin |last=Bonsor |url=http://electronics.howstuffworks.com/satellite-radio.htm |title=How Satellite Radio Works |website=[[HowStuffWorks]] |access-date=May 1, 2013|date=2001-09-26 }}</ref> Its first broadcast occurred on September 25, 2001, nearly four months before Sirius.<ref name="sparker">{{cite news |first=Steve |last=Parker |url=http://www.huffingtonpost.com/steve-parker/xm-plus-sirius-satellite_b_114678.html |title=XM plus Sirius = Satellite Radio Monopoly |work=[[Huffington Post]] |date=July 24, 2008}}</ref> Sirius launched the initial phase of its service in four cities on February 14, 2002,<ref>{{cite news |url=http://radiomagonline.com/currents/business/radio_sirius_begins_satellite/ |title=Sirius Begins Satellite Service |work=[[Radio (magazine)|Radio]] |date=February 14, 2002 |url-status=dead |archive-url=https://web.archive.org/web/20170607222527/http://www.radiomagonline.com/currents/business/radio_sirius_begins_satellite |archive-date=June 7, 2017 }}</ref> expanding to the rest of the contiguous United States on July 1, 2002.<ref name="sparker"/> The two companies spent over $3 billion combined to develop satellite radio technology, build and launch the satellites, and for various other business expenses.<ref name="spacefoundation"/> Stating that it was the only way satellite radio could survive, Sirius and XM announced their merger on February 19, 2007, becoming Sirius XM.<ref>{{cite news |first=Kim |last=Hart |url=https://www.washingtonpost.com/wp-dyn/content/article/2008/07/25/AR2008072503026.html?hpid=topnews |title=Satellite Radio Merger Approved |work=[[Washington Post]] |date=July 26, 2008}}</ref><ref>{{cite news |first1=Richard |last1=Siklos  |first2=Andrew Ross |last2=Sorkin |url=https://www.nytimes.com/2007/02/20/business/media/20radio.html?pagewanted=all |title=Merger Would End Satellite Radio's Rivalry |work=New York Times |date=February 20, 2007}}</ref> The FCC approved the merger on July 25, 2008, concluding that it was not a monopoly, primarily due to Internet audio-streaming competition.<ref>{{cite news |first=Olga |last=Kharif |url=http://www.businessweek.com/stories/2008-07-25/the-fcc-approves-the-xm-sirius-mergerbusinessweek-business-news-stock-market-and-financial-advice |title=The FCC Approves the XM-Sirius Merger |work=[[Bloomberg Businessweek]] |date=July 25, 2008}}</ref>\n\n MobaHo! was a mobile satellite digital audio/video broadcasting service based in [[Japan]] which offered different services to  Japan and the Republic of Korea and whose services began on October 20, 2004, and ended on March 31, 2009.<ref>{{cite news |first=Tim |last=Conneally |url=http://betanews.com/2008/07/30/toshiba-to-shut-down-mobile-broadcast-tv-service/ |title=Toshiba to shut down mobile broadcast TV service |work=betanews.com |date=July 30, 2008}}</ref>\n\n XM satellite radio was launched in Canada on November 29, 2005. Sirius followed two days later on December 1, 2005. [[Sirius Canada]] and [[XM Radio Canada]] announced their merger into [[Sirius XM Canada]] on November 24, 2010.<ref>{{cite web |first=Emil |last=Protalinski |url=http://www.techspot.com/news/41302-xm-and-sirius-to-finally-merge-in-canada.html |title=XM and Sirius to finally merge in Canada |website=techspot.com |date=November 25, 2010}}</ref> It was approved by the [[Canadian Radio-television and Telecommunications Commission]] on April 12, 2011.<ref>{{cite web |url=http://www.allaccess.com/net-news/archive/story/89975/crtc-approves-sirius-xm-merger-in-canada |title=CRTC Approves Sirius XM Merger In Canada |website=All Access |date=April 12, 2011}}</ref>"}},
{"article_title": "Well drilling", "pageid": "67488", "revid": "1049112922", "timestamp": "2021-10-09T22:30:29Z", "history_paths": [["Well drilling --- Introduction ---", "History"]], "categories": ["american inventions", "chinese inventions", "drilling technology", "water wells"], "heading_tree": {"Well drilling --- Introduction ---": {"History": {}, "Drill bits in mechanical drilling": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Well drilling --- Introduction ---|History": "The earliest record of well drilling dates from 347 AD in China.<ref name="Vogt">{{cite book|author=Kristiina A. Vogt|title=Sustainability Unpacked: Food, Energy and Water for Resilient Environments and Societies|url=https://books.google.com/books?id=oTI2rOXbEAwC&pg=PT47|date=25 June 2012|publisher=Routledge|isbn=978-1-136-53060-9|page=47|quote=The first record of drilling for oil occurred in China in 347 CE}}</ref> Petroleum was used in ancient China for "lighting, as a lubricant for cart axles and the bearings of water-powered drop hammers, as a source of carbon for [[inkstick]]s, and as a medical remedy for sores on humans and [[mange]] in animals."<ref name="Golas">{{cite book|author=Peter J. Golas|title=Science and Civilisation in China: Volume 5, Chemistry and Chemical Technology, Part 13, Mining|date=25 February 1999|publisher=Cambridge University Press|isbn=978-0-521-58000-7|page=202}}</ref> In ancient China, deep well drilling machines were in the forefront of brine well production by the 1st century BC. The ancient Chinese developed advanced sinking wells and were the first civilization to use a well-drilling machine and to use bamboo well casings to keep the holes open.<ref>{{Cite book |title=Applied Principles of Hydrology |last=Manning |first=John C.  |publisher= Prentice Hall |year=1996 |isbn= 978-0135655320 |edition=3rd |publication-date=June 24, 1996 |page=154}}</ref><ref>{{Cite book |title=The Technology of Ancient China |last=Greenberger |first=Robert |publisher=Rosen Publishing Group |year=2005 |isbn=978-1404205581 |pages=[https://archive.org/details/technologyofanci0000gree/page/27 27] |url-access=registration |url=https://archive.org/details/technologyofanci0000gree/page/27 }}</ref>\n\nIn the modern era, the first roller cone [[patent]] was for the rotary rock bit and was issued to American businessman and inventor [[Howard Hughes Sr.]] in 1909. It consisted of two interlocking cones. American businessman [[Walter Benona Sharp]] worked very closely with Hughes in developing the rock bit. The success of this bit led to the founding of the [[Sharp-Hughes Tool Company]]. In 1933 two Hughes engineers, one of whom was Ralph Neuhaus, invented the tricone bit, which has three cones.  The Hughes patent for the tricone bit lasted until 1951, after which other companies made similar bits. However, Hughes still held 40% of the world's drill bit market in 2000. The superior wear performance of [[Diamond tool#PCD cutting tools|polycrystalline diamond compact]] (PDC) bits gradually eroded the dominance of roller cone bits and early in this century PDC drill bit revenues overtook those of roller cone bits. The technology of both bit types has advanced significantly to provide improved durability and rate of penetration of the rock. This has been driven by the economics of the industry, and by the change from the empirical approach of Hughes in the 1930s, to modern day domain Finite Element codes for both the hydraulic and cutter placement software."}},
{"article_title": "Tennessine", "pageid": "67611", "revid": "1059732493", "timestamp": "2021-12-11T07:32:25Z", "history_paths": [["Tennessine --- Introduction ---", "History"]], "categories": ["tennessine", "chemical elements", "halogens", "synthetic elements", "science and technology in tennessee"], "heading_tree": {"Tennessine --- Introduction ---": {"Introduction": {}, "History": {"Pre-discovery": {}, "Discovery": {}, "Confirmation": {}, "Naming": {}}, "Predicted properties": {"Nuclear stability and isotopes": {}, "Atomic and physical": {}, "Chemical": {}}, "Notes": {}, "References": {}, "Bibliography": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Tennessine --- Introduction ---|History": "{{see also|Timeline of chemical element discoveries}}\n\n In December 2004, the [[Joint Institute for Nuclear Research]] (JINR) team in [[Dubna]], [[Moscow Oblast]], Russia, proposed a joint experiment with the [[Oak Ridge National Laboratory]] (ORNL) in [[Oak Ridge, Tennessee|Oak Ridge]], [[Tennessee]], United States, to synthesize element 117 \u2014 so called for the 117 [[proton]]s in its [[atomic nucleus|nucleus]]. Their proposal involved [[nuclear fusion|fusing]] a [[berkelium]] (element 97) target and a [[calcium]] (element 20) beam, conducted via bombardment of the berkelium target with calcium nuclei:<ref name="elements">{{cite press release |last=Cabage |first=B. |date=2010 |title=International team discovers element 117 |publisher=[[Oak Ridge National Laboratory]] |url=http://web.ornl.gov/info/ornlreview/v43_2_10/article02.shtml |url-status=dead |access-date=2017-06-26 |archive-url=https://web.archive.org/web/20150923175349/http://web.ornl.gov/info/ornlreview/v43_2_10/article02.shtml |archive-date=2015-09-23}}</ref> this would complete a set of experiments done at the JINR on the fusion of [[actinide]] targets with a calcium-48 beam, which had thus far produced the new elements [[nihonium|113]]\u2013[[livermorium|116]] and [[oganesson|118]]. The ORNL\u2014then the world's only producer of berkelium\u2014could not then provide the element, as they had temporarily ceased production,<ref name="elements" /> and re-initiating it would be too costly.<ref name="vanderbilt">{{cite press release |title=Vanderbilt physicist plays pivotal role in discovery of new super-heavy element |publisher=Vanderbilt University |date=April 2010 |url=http://news.vanderbilt.edu/2010/04/vanderbilt-physicist-plays-pivotal-role-in-discovery-of-new-super-heavy-element-112107/ |access-date=2016-06-12}}</ref> Plans to synthesize element 117 were suspended in favor of the confirmation of element 118, which had been produced earlier in 2002 by bombarding a [[californium]] target with calcium.<ref name="pp2002">{{cite journal |last1=Oganessian |first1=Yu.Ts. |last2=Utyonkov |first2=V.K. |last3=Lobanov |first3=Yu.V. |last4=Abdullin |first4=F.Sh. |last5=Polyakov |first5=A.N. |last6=Shirokovsky |first6=I.V. |last7=Tsyganov |first7=Yu.S. |last8=Mezentsev |first8=A.N. |display-authors=6 |year=2002 |title=Results from the first <sup>249</sup>Cf+<sup>48</sup>Ca experiment |journal=JINR Communication |url=http://www.jinr.ru/publish/Preprints/2002/287(D7-2002-287)e.pdf |access-date=2015-09-23}}</ref> The required berkelium-249 is a by-product in californium-252 production, and obtaining the required amount of berkelium was an even more difficult task than obtaining that of californium, as well as costly: It would cost around 3.5 million dollars, and the parties agreed to wait for a commercial order of californium production, from which berkelium could be extracted.<ref name="vanderbilt" /><ref name="InsideScience" />\n\nThe JINR team sought to use berkelium because [[calcium-48]], the [[isotopes of calcium|isotope of calcium]] used in the beam, has 20 protons and 28 neutrons, making a neutron\u2013proton ratio of 1.4; and it is the lightest stable or near-stable nucleus with such a large neutron excess. The second-lightest such nucleus, [[palladium-110]] (46 protons, 64 neutrons, neutron\u2013proton ratio of 1.391), is much heavier. Thanks to the neutron excess, the resulting nuclei were expected to be heavier and closer to the sought-after [[island of stability]].{{efn|Although stable isotopes of the lightest elements usually have a neutron\u2013proton ratio close or equal to one (for example, the only stable isotope of [[aluminium]] has 13 protons and 14 neutrons,<ref name="NUBASE" /> making a neutron\u2013proton ratio of 1.077), stable isotopes of heavier elements have higher neutron\u2013proton ratios, increasing with the number of protons. For example, [[iodine]]'s only stable isotope has 53 protons and 74 neutrons, giving neutron\u2013proton ratio of 1.396, [[gold]]'s only stable isotope has 79 protons and 118 neutrons, yielding a neutron\u2013proton ratio of 1.494, and [[plutonium]]'s most stable isotope has 94 protons and 150 neutrons, and a neutron\u2013proton ratio of 1.596.<ref name="NUBASE" /> This trend<ref>{{cite book |last1=Karpov |first1=A. V. |last2=Zagrebaev |first2=V. I. |last3=Palenzuela |first3=Y. Martinez |last4=Greiner |first4=Walter |year=2013 |chapter=Superheavy Nuclei: Decay and Stability |title=Exciting Interdisciplinary Physics |page=69 |series=FIAS Interdisciplinary Science Series |doi=10.1007/978-3-319-00047-3_6 |isbn=978-3-319-00046-6}}</ref> is expected to make it difficult to synthesize the most stable isotopes of super-heavy elements as the neutron\u2013proton ratios of the elements they are synthesized from will be too low.}} Of the aimed for 117 protons, calcium has 20, and thus they needed to use berkelium, which has 97 protons in its nucleus.<ref name="NUBASE">{{cite journal |last1=Audi |first1=G. |last2=Bersillon |first2=O. |last3=Blachot |first3=J. |last4=Wapstra |first4=A.H. |year=2003 |title=The NUBASE evaluation of nuclear and decay properties |journal=[[Nuclear Physics A]] |volume=729 |issue=1 |pages=3\u2013128 |bibcode=2003NuPhA.729....3A |citeseerx=10.1.1.692.8504 |doi=10.1016/j.nuclphysa.2003.11.001 |url=http://amdc.in2p3.fr/nubase/Nubase2003.pdf |url-status=dead |archive-url=https://web.archive.org/web/20110720233206/http://amdc.in2p3.fr/nubase/Nubase2003.pdf |archive-date=2011-07-20}}</ref>\n\nIn February 2005, the leader of the JINR team \u2014 [[Yuri Oganessian]] \u2014 presented a colloquium at ORNL. Also in attendance were representatives of Lawrence Livermore National Laboratory, who had previously worked with JINR on the discovery of elements 113\u2013116 and 118, and Joseph Hamilton of [[Vanderbilt University]], a collaborator of Oganessian.<ref name="Oganessian" />\n\nHamilton checked if the ORNL high-flux reactor produced californium for a commercial order: The required berkelium could be obtained as a by-product. He learned that it did not and there was no expectation for such an order in the immediate future. Hamilton kept monitoring the situation, making the checks once in a while. (Later, Oganessian referred to Hamilton as "the father of 117" for doing this work.)<ref name="Oganessian">{{cite news |title=What it takes to make a new element |magazine=Chemistry World |url=https://www.chemistryworld.com/what-it-takes-to-make-a-new-element/1017677.article |access-date=2016-12-03}}</ref>\n\n ORNL resumed californium production in spring 2008. Hamilton noted the restart during the summer and made a deal on subsequent extraction of berkelium<ref>{{cite web |last=Witze |first=Alexandra |year=2010 |title=The backstory behind a new element |website=Science News |url=https://www.sciencenews.org/blog/deleted-scenes/backstory-behind-new-element |access-date=2016-06-12}}</ref> (the price was about $600,000).<ref name="Bloomberg" /> During a September 2008 symposium at [[Vanderbilt University]] in [[Nashville, Tennessee|Nashville]], Tennessee celebrating his 50th year on the Physics faculty, he introduced Oganessian to James Roberto (then the deputy director for science and technology at ORNL).<ref name="symposiumintro">{{cite news |first=Emily |last=Siner |year=2016 |title=How scientists plan to enshrine Tennessee on the periodic table of elements |publisher=National Public Radio |url=http://nashvillepublicradio.org/post/how-scientists-plan-enshrine-tennessee-periodic-table-elements |access-date=2017-03-07}}</ref> They established a collaboration among JINR, ORNL, and Vanderbilt;<ref name="InsideScience" /> the team at the [[Lawrence Livermore National Laboratory]] (LLNL) in [[Livermore, California|Livermore]], [[California]], U.S., was soon invited to join.<ref name="discoveryornl">{{cite press release |first=James |last=Roberto |year=2010 |publisher=Oak Ridge National Laboratory |title=The discovery of element 117 |url=http://www.fornl.info/Presentations/Discovery%20of%20Element%20117%20final.pdf |access-date=2017-06-26 |url-status=dead |archive-url=https://web.archive.org/web/20161021230058/http://www.fornl.info/Presentations/Discovery%20of%20Element%20117%20final.pdf |archive-date=2016-10-21}}</ref>[[File:Berkelium.jpg|thumb|left|The berkelium target used for the synthesis (in solution)|alt=A very small sample of a blue liquid in a plastic pipette held by a hand wearing heavy protection equipment]]\nIn November 2008, the [[United States Department of Energy|U.S. Department of Energy]], which had oversight over the [[High Flux Isotope Reactor|reactor in Oak Ridge]], allowed the scientific use of the extracted berkelium.<ref name="discoveryornl" /> The production lasted 250 days and ended in late December 2008,<ref name="forthepress" /> resulting in 22 milligrams of berkelium, enough to perform the experiment.<ref name="eurekalert" /> In January 2009, the berkelium was removed from ORNL's High Flux Isotope Reactor;<ref name="discoveryornl" /> it was subsequently cooled for 90 days and then processed at ORNL's Radiochemical Engineering and Development Center to separate and purify the berkelium material, which took another 90 days.<ref name="InsideScience" /> Its [[half-life]] is only 330 days: after that time, half the berkelium produced would have [[radioactive decay|decayed]]. Because of this, the berkelium target had to be quickly transported to Russia; for the experiment to be viable, it had to be completed within six months of its departure from the United States.<ref name="InsideScience">{{cite web |title=An Atom at the End of the Material World |year=2010 |first=J. S. |last=Bardi |url=http://www.insidescience.org/content/atom-end-material-world/1042 |publisher=Inside Science |access-date=2015-01-03 }}</ref> The target was packed into five lead containers to be flown from New York to Moscow.<ref name="InsideScience" />\n\nRussian customs officials twice refused to let the target enter the country because of missing or incomplete paperwork. Over the span of a few days, the target traveled over the Atlantic Ocean five times.<ref name="InsideScience" /> On its arrival in Russia in June 2009, the berkelium was immediately transferred to [[Research Institute of Atomic Reactors]] (RIAR) in [[Dimitrovgrad (Russia)|Dimitrovgrad]], [[Ulyanovsk Oblast]], where it was deposited as a 300-[[nanometer]]-thin layer on a [[titanium]] film.<ref name="forthepress">{{cite press release |publisher=[[Joint Institute for Nuclear Research]] |title=For the Press |year=2010 |url=http://flerovlab.jinr.ru/linkc/117/For%20press%20Z=117.doc |access-date=2015-07-28 |archive-date=4 March 2016 |archive-url=https://web.archive.org/web/20160304120450/http://flerovlab.jinr.ru/linkc/117/For%20press%20Z=117.doc |url-status=dead }}</ref> In July 2009, it was transported to Dubna,<ref name="forthepress" /> where it was installed in the [[particle accelerator]] at the JINR.<ref name="eurekalert">{{cite press release |last=Stark |first=A.M. |year=2010  |title=International team discovers element 117 |publisher=[[United States Department of Energy|DOE]] / [[Lawrence Livermore National Laboratory]] |url=http://www.eurekalert.org/pub_releases/2010-04/dlnl-itd040610.php |access-date=2012-11-29 }}</ref> The [[calcium-48]] beam was generated by [[extraction (chemistry)|chemically extracting]] the small quantities of calcium-48 present in naturally occurring calcium, enriching it 500 times.{{citation needed|date=November 2020}} This work was done in the [[Closed city|closed town]] of [[Lesnoy, Sverdlovsk Oblast|Lesnoy]], [[Sverdlovsk Oblast]], Russia.<ref name="discoveryornl" />\n\nThe experiment began in late July 2009.<ref name="discoveryornl" /> In January 2010, scientists at the [[Flerov Laboratory of Nuclear Reactions]] announced internally that they had detected the [[Radioactive decay|decay]] of a new element with atomic number 117 via two decay chains: one of an [[odd-odd nuclei|odd\u2013odd]] isotope undergoing 6 [[alpha decay]]s before [[spontaneous fission]], and one of an [[odd-even nuclei|odd\u2013even]] isotope undergoing 3 alpha decays before fission.<ref name="E117">{{cite conference |url=http://www.jinr.ru/img_sections/PAC/NP/31/PAK_NP_31_recom_eng.pdf |title=Recommendations|conference=31st meeting, PAC for nuclear physics |last=Greiner |first=W. |page=6 |date=2010 |url-status=dead |archive-url=https://web.archive.org/web/20100414173735/http://www.jinr.ru/img_sections/PAC/NP/31/PAK_NP_31_recom_eng.pdf |archive-date=2010-04-14}}</ref> The obtained data from the experiment was sent to the LLNL for further analysis.<ref>{{cite press release |title=Nations work together to discover new element |year=2011 |publisher=U.S. [[Department of Energy]] |department=DOE Office of Science |website=[[U.S. Department of Energy]] |url=http://science.energy.gov/news/featured-articles/2011/127004/ |access-date=2016-01-05}}</ref> On 9 April 2010, an official report was released in the journal ''[[Physical Review Letters]]'' identifying the isotopes as <sup>294</sup>117 and <sup>293</sup>117, which were shown to have half-lives on the [[order of magnitude|order]] of tens or hundreds of [[millisecond]]s. The work was signed by all parties involved in the experiment to some extent: JINR, ORNL, LLNL, RIAR, Vanderbilt, the [[University of Tennessee]] ([[Knoxville, Tennessee|Knoxville]], [[Tennessee]], U.S.), and the [[University of Nevada, Las Vegas|University of Nevada]] ([[Las Vegas, Nevada|Las Vegas]], [[Nevada]], U.S.), which provided data analysis support.<ref name="vanderbilt.edu">{{cite web |title=Heaviest in the world |date=November 2011 |website=Arts and Science Magazine |publisher=Vanderbilt University |url=http://www.vanderbilt.edu/magazines/arts-and-science/2010-11/heaviest-in-the-world/ |access-date=2016-06-12 |url-status=dead |archive-url=https://web.archive.org/web/20160503072001/http://www.vanderbilt.edu/magazines/arts-and-science/2010-11/heaviest-in-the-world/ |archive-date=2016-05-03}}</ref> The isotopes were formed as follows:<ref name="117s" />{{efn|A nuclide is commonly denoted by the chemical element's symbol immediately preceded by the mass number as a superscript and the atomic number as a subscript. Neutrons are represented as nuclides with atomic mass 1, atomic number 0, and symbol '''n'''. Outside the context of nuclear equations, the atomic number is sometimes omitted. An asterisk denotes an extremely short-lived (or even non-existent) intermediate stage of the reaction.}}\n\n:{{nuclide|Berkelium|249}} + {{nuclide|calcium|48}} \u2192 <sup>297</sup>117* \u2192 <sup>294</sup>117 + 3 {{su|b=0|p=1}}{{SubatomicParticle|neutron}} (1 event)\n\n:{{nuclide|Berkelium|249}} + {{nuclide|calcium|48}} \u2192 <sup>297</sup>117* \u2192 <sup>293</sup>117 + 4 {{su|b=0|p=1}}{{SubatomicParticle|neutron}} (5 events)\n\n [[File:DecayChain Tennessine.svg|thumb|upright=1.5|Decay chain of the atoms produced in the original experiment. The figures near the arrows describe experimental (black) and theoretical (blue) values for the lifetime and [[decay energy|energy]] of each decay. Lifetimes may be converted to [[half-life|half-lives]] by multiplying by [[Natural logarithm of 2|ln 2]].<ref name="117s" />]]\nAll [[daughter isotope]]s (decay products) of element 117 were previously unknown;<ref name="117s">{{cite journal|last1=Oganessian |first1=Yu.Ts. |author-link1=Yuri Oganessian |last2=Abdullin |first2=F.Sh. |last3=Bailey |first3=P.D. |last4=Benker |first4=D.E. |last5=Bennett |first5=M.E. |last6=Dmitriev |first6=S.N. |last7=Ezold |first7=J.G. |last8=Hamilton |first8=J.H. |last9=Henderson |first9=R.A. |first10=M.G. |last10=Itkis |first11=Yuri V. |last11=Lobanov |first12=A.N. |last12=Mezentsev |first13=K. J. |last13=Moody |first14=S.L. |last14=Nelson |first15=A.N. |last15=Polyakov | first16=C.E. |last16=Porter |first17=A.V. |last17=Ramayya |first18=F.D. |last18=Riley |first19=J.B. |last19=Roberto |first20=M. A. |last20=Ryabinin | first21=K.P. |last21=Rykaczewski |first22=R.N. |last22=Sagaidak | first23=D.A. |last23=Shaughnessy |first24=I.V. |last24=Shirokovsky |first25=M.A. |last25=Stoyer |first26=V.G. |last26=Subbotin | first27=R. |last27=Sudowe |first28=A.M. |last28=Sukhov |first29=Yu.S. |last29=Tsyganov |first30=Vladimir K. |last30=Utyonkov |first31=A.A. |last31=Voinov |first32=G.K. |last32=Vostokin | first33=P.A. |last33=Wilk |display-authors=6 |title=Synthesis of a new element with atomic number {{nowrap|{{mvar|Z}} {{=}} 117}} |year=2010 |journal=Physical Review Letters |volume=104 |issue=14 |page=142502 |doi=10.1103/PhysRevLett.104.142502 |pmid=20481935 |bibcode=2010PhRvL.104n2502O |s2cid=3263480 |url=https://semanticscholar.org/paper/ec9412add23e66f34b6bf51ebd7332278af413fc}}</ref> therefore, their properties could not be used to confirm the claim of discovery. In 2011, when one of the decay products ({{sup|289}}115) was synthesized directly, its properties matched those measured in the claimed indirect synthesis from the decay of element 117.<ref>{{cite web |last=Molchanov |first=E. |year=2011 |script-title=ru:\u0412 \u043b\u0430\u0431\u043e\u0440\u0430\u0442\u043e\u0440\u0438\u044f\u0445 \u041e\u0418\u042f\u0418. \u0412\u043e\u0437\u0432\u0440\u0430\u0449\u0435\u043d\u0438\u0435 \u043a \u0434\u0443\u0431\u043d\u0438\u044e |trans-title=In JINR labs. Returning to dubnium |publisher=JINR |url=http://www.jinr.ru/news_article.asp?n_id=954&language=rus |access-date=2011-11-09 |language=ru}}</ref> The discoverers did not submit a claim for their findings in 2007\u20132011 when the [[IUPAC/IUPAP Joint Working Party|Joint Working Party]] was reviewing claims of discoveries of new elements.<ref>{{cite journal |last1=Barber |first1=R.C. |last2=Karol |first2=P.J. |last3=Nakahara |first3=H. |last4=Vardaci |first4=E. |last5=Vogt |first5=E.W. |year=2011 |title=Discovery of the elements with atomic numbers greater than or equal to 113 |series=IUPAC Technical Report |journal=Pure and Applied Chemistry |volume=83 |issue=7 |pages=1485\u20131498 |s2cid=98065999 |doi=10.1351/PAC-REP-10-05-01}}</ref>\n\nThe Dubna team repeated the experiment in 2012, creating seven atoms of element 117 and confirming their earlier synthesis of element 118 (produced after some time when a significant quantity of the [[berkelium]]-249 target had [[beta decay]]ed to [[californium]]-249). The results of the experiment matched the previous outcome;<ref name="277Mt" /> the scientists then filed an application to register the element.{{citation needed|date=November 2020}} In May 2014, a joint German\u2013American collaboration of scientists from the ORNL and the [[GSI Helmholtz Center for Heavy Ion Research]] in [[Darmstadt]], [[Hessen]], Germany, claimed to have confirmed discovery of the element.<ref name="266Lr" /><ref>{{cite web |first=D. |last=Chow |date=2014-05-01 |title=New super-heavy element 117 confirmed by scientists |publisher=Live Science |url=http://www.livescience.com/45289-superheavy-element-117-confirmed.html |access-date=2014-05-02}}</ref> The team repeated the Dubna experiment using the Darmstadt accelerator, creating two atoms of element 117.<ref name="266Lr" />\n\nIn December 2015, the JWP officially recognized the discovery of <sup>293</sup>117 on account of the confirmation of the properties of its daughter {{sup|289}}115,<ref>{{cite press release |title=Discovery and assignment of elements with atomic numbers 113, 115, 117 and 118 |publisher=IUPAC |year=2015 |url=http://www.iupac.org/news/news-detail/article/discovery-and-assignment-of-elements-with-atomic-numbers-113-115-117-and-118.html |access-date=2016-01-04}}</ref> and thus the listed discoverers \u2014 JINR, LLNL, and ORNL \u2014 were given the right to suggest an official name for the element. (Vanderbilt was left off the initial list of discoverers in an error that was later corrected.)<ref>{{cite journal |last1=Karol |first1=Paul J. |last2=Barber |first2=Robert C. |last3=Sherrill |first3=Bradley M. |last4=Vardaci |first4=Emanuele |last5=Yamazaki |first5=Toshimitsu |date=22 December 2015 |title=Discovery of the elements with atomic numbers {{nowrap|{{mvar|Z}} {{=}} 113,}} 115, and 117 |series=IUPAC Technical Report |journal=Pure Appl. Chem. |volume=88 |issue=1\u20132 |pages=139\u2013153 |doi=10.1515/pac-2015-0502 |s2cid=101634372 |url=https://www.degruyter.com/downloadpdf/j/pac.2016.88.issue-1-2/pac-2015-0502/pac-2015-0502.pdf |access-date=2 April 2016}}</ref>\n\nIn May 2016, [[Lund University]] ([[Lund]], [[Scania]], Sweden) and GSI cast some doubt on the syntheses of elements [[Moscovium|115]] and 117. The decay chains assigned to {{sup|289}}115, the isotope instrumental in the confirmation of the syntheses of elements 115 and 117, were found based on a new statistical method to be too different to belong to the same nuclide with a reasonably high probability. The reported <sup>293</sup>117 decay chains approved as such by the JWP were found to require splitting into individual data sets assigned to different isotopes of element 117. It was also found that the claimed link between the decay chains reported as from {{sup|293}}117 and {{sup|289}}115 probably did not exist. (On the other hand, the chains from the non-approved isotope {{sup|294}}117 were found to be [[wikt:congruent|congruent]].) The multiplicity of states found when nuclides that are not even\u2013even undergo alpha decay is not unexpected and contributes to the lack of clarity in the cross-reactions. This study criticized the JWP report for overlooking subtleties associated with this issue, and considered it "problematic" that the only argument for the acceptance of the discoveries of elements 115 and 117 was a link they considered to be doubtful.<ref>{{cite journal |last1=Forsberg |first1=U. |last2=Rudolph |first2=D. |first3=C. |last3=Fahlander |first4=P. |last4=Golubev |first5=L.G. |last5=Sarmiento |first6=S. |last6=\u00c5berg |first7=M. |last7=Block |first8=Ch.E. |last8=D\u00fcllmann |first9=F.P. |last9=He\u00dfberger |first10=J.V. |last10=Kratz |first11=A. |last11=Yakushev |date=9 July 2016 |title=A new assessment of the alleged link between element 115 and element 117 decay chains |journal=Physics Letters B |volume=760 |issue=2016 |pages=293\u2013296 |doi=10.1016/j.physletb.2016.07.008 |bibcode=2016PhLB..760..293F |url=http://portal.research.lu.se/portal/files/9762047/PhysLettB760_293_2016.pdf |access-date=2 April 2016|doi-access=free }}</ref><ref>{{cite conference |last1=Forsberg |first1=Ulrika |last2=Fahlander |first2=Claes |last3=Rudolph |first3=Dirk |year=2016 |title=Congruence of decay chains of elements 113, 115, and 117  |conference=Nobel Symposium NS160 \u2013 Chemistry and Physics of Heavy and Superheavy Elements |doi=10.1051/epjconf/201613102003 |url=http://www.epj-conferences.org/articles/epjconf/pdf/2016/26/epjconf-NS160-02003.pdf|doi-access=free }}</ref>\n\nOn 8 June 2017, two members of the Dubna team published a journal article answering these criticisms, analysing their data on the nuclides {{sup|293}}117 and {{sup|289}}115 with widely accepted statistical methods, noted that the 2016 studies indicating non-congruence produced problematic results when applied to radioactive decay: they excluded from the 90% confidence interval both average and extreme decay times, and the decay chains that would be excluded from the 90% confidence interval they chose were more probable to be observed than those that would be included. The 2017 reanalysis concluded that the observed decay chains of {{sup|293}}117 and {{sup|289}}115 were consistent with the assumption that only one nuclide was present at each step of the chain, although it would be desirable to be able to directly measure the mass number of the originating nucleus of each chain as well as the excitation function of the {{nowrap|[[Americium|{{sup|243}}Am]] + [[Calcium-48|{{sup|48}}Ca]]}} reaction.<ref>{{cite journal |last1=Zlokazov |first1=V.B. |last2=Utyonkov |first2=V.K. |date=8 June 2017 |title=Analysis of decay chains of superheavy nuclei produced in the {{nowrap|{{sup|249}}Bk + {{sup|48}}Ca}} and {{nowrap|{{sup|243}}Am + {{sup|48}}Ca}} reactions |journal=Journal of Physics G: Nuclear and Particle Physics |volume=44 |issue=7 |page=075107 |doi=10.1088/1361-6471/aa7293 |doi-access=free |bibcode=2017JPhG...44g5107Z}}</ref>\n\n [[File:CorneliusVanderbiltStatue.JPG|thumb|left|Main campus of Hamilton's workplace, Vanderbilt University, one of the institutions named as co-discoverers of tennessine]]\nUsing [[Mendeleev's predicted elements|Mendeleev's nomenclature for unnamed and undiscovered elements]], element 117 should be known as ''eka-[[astatine]]''. Using the 1979 [[systematic element name|recommendations]] by the [[International Union of Pure and Applied Chemistry]] (IUPAC), the element was [[placeholder name|temporarily called]] ''ununseptium'' (symbol ''Uus'') until its discovery was confirmed and a permanent name chosen; the temporary name was formed from [[Latin language|Latin]] roots "one", "one", and "seven", a reference to the element's atomic number 117.<ref name="iupac">{{cite journal |last=Chatt |first=J. |date=1979 |title=Recommendations for the naming of elements of atomic numbers greater than 100 |journal=Pure Appl. Chem. |volume=51 |issue=2 |pages=381\u2013384 |doi=10.1351/pac197951020381}}</ref> Many scientists in the field called it "element 117", with the symbol ''E117'', ''(117)'', or ''117''.<ref name="Haire" /> According to guidelines of IUPAC valid at the moment of the discovery approval, the permanent names of new elements should have ended in "-ium"; this included element 117, even if the element was a [[halogen]], which traditionally have names ending in "-ine";<ref>{{cite journal |last=Koppenol |first=W.H. |year=2002 |title=Naming of new elements |series=IUPAC Recommendations 2002 |journal=Pure and Applied Chemistry |volume=74 |issue=5 |pages=787\u2013791 |s2cid=95859397 |doi=10.1351/pac200274050787 |url=http://media.iupac.org/publications/pac/2002/pdf/7405x0787.pdf}}</ref> however, the new recommendations published in 2016 recommended using the "-ine" ending for all new group 17 elements.<ref>{{cite journal |last1=Koppenol |first1=Willem H. |last2=Corish |first2=John |last3=Garc\u00eda-Mart\u00ednez |first3=Javier |last4=Meija |first4=Juris |last5=Reedijk |first5=Jan |year=2016 |title=How to name new chemical elements |series=IUPAC Recommendations 2016 |journal=Pure and Applied Chemistry |volume=88 |issue=4 |pages=401\u2013405 |doi=10.1515/pac-2015-0802 |hdl=10045/55935 |s2cid=102245448 |url=http://rua.ua.es/dspace/bitstream/10045/55935/1/2016_Koppenol_etal_PureApplChem.pdf|hdl-access=free }}</ref>\n\nAfter the original synthesis in 2010, [[Dawn Shaughnessy]] of LLNL and Oganessian declared that naming was a sensitive question, and it was avoided as far as possible.<ref>{{cite press release |last=Glanz |first=J. |year=2010 |title=Scientists discover heavy new element |publisher=[[Oregon State University]] |department=Department of Chemistry |url=http://chemistry.oregonstate.edu/courses/ch121-3/ch123/ch123latestnews/ch123ln.htm |access-date=2016-01-05}}</ref> However, Hamilton declared that year, "I was crucial in getting the group together and in getting the <sup>249</sup>Bk target essential for the discovery. As a result of that, I'm going to get to name the element. I can't tell you the name, but it will bring distinction to the region."<ref name="vanderbilt.edu" /> (Hamilton teaches at [[Vanderbilt University]] in [[Nashville, Tennessee]], U.S.) In a 2015 interview, Oganessian, after telling the story of the experiment, said, "and the Americans named this a tour de force, they had demonstrated they could do [this] with no margin for error. Well, soon they will name the 117th element."<ref name="OTR">{{cite interview |last=Oganessian |first=Yu.Ts. |title=\u0413\u0430\u043c\u0431\u0443\u0440\u0433\u0441\u043a\u0438\u0439 \u0441\u0447\u0435\u0442 |url=https://www.youtube.com/watch?v=ZdnvOxxDeKM | archive-url=https://ghostarchive.org/varchive/youtube/20211111/ZdnvOxxDeKM| archive-date=2021-11-11 | url-status=live|access-date=2020-01-18 |date=2015-10-10 |interviewer-last=Orlova |interviewer-first=O. |trans-title=Hamburg reckoning |language=ru |publisher=[[Public Television of Russia]]}}{{cbignore}}</ref>\n\nIn March 2016, the discovery team agreed on a conference call involving representatives from the parties involved on the name "tennessine" for element 117.<ref name="Oganessian" /> In June 2016, IUPAC published a declaration stating the discoverers had submitted their suggestions for naming the new elements 115, 117, and 118 to the IUPAC; the suggestion for the element 117 was ''tennessine'', with a symbol of ''Ts'', after "the region of Tennessee".{{efn|name=fn1}} The suggested names were recommended for acceptance by the IUPAC Inorganic Chemistry Division; formal acceptance was set to occur after a five-months term following publishing of the declaration expires.<ref name="IUPAC-June2016">{{cite press release | url = http://iupac.org/iupac-is-naming-the-four-new-elements-nihonium-moscovium-tennessine-and-oganesson/ | title = IUPAC Is Naming The Four New Elements Nihonium, Moscovium, Tennessine, and Oganesson | date = 2016-06-08 | publisher = IUPAC | access-date = 2016-06-08}}</ref> In November 2016, the names, including tennessine, were formally accepted. Concerns that the proposed symbol ''Ts'' may clash with a notation for the [[tosyl]] group used in organic chemistry were rejected, following existing symbols bearing such dual meanings: Ac ([[actinium]] and [[Acetyl group|acetyl]]) and Pr ([[praseodymium]] and [[Propyl group|propyl]]).<ref>{{Cite news |url=https://iupac.org/iupac-announces-the-names-of-the-elements-113-115-117-and-118/ |title=IUPAC Announces the Names of the Elements 113, 115, 117, and 118 - IUPAC {{!}} International Union of Pure and Applied Chemistry |date=2016-11-30 |newspaper=IUPAC {{!}} International Union of Pure and Applied Chemistry |language=en-US |access-date=2016-11-30}}</ref> The naming ceremony for moscovium, tennessine, and oganesson was held on 2 March 2017 at the [[Russian Academy of Sciences]] in [[Moscow]]; a separate ceremony for tennessine alone had been held at ORNL in January<!--the 27th--> 2017.<ref>{{cite web |url=http://www.jinr.ru/posts/at-the-inauguration-ceremony-of-the-new-elements-of-the-periodic-table-of-d-i-mendeleev/ |title=At the inauguration ceremony of the new elements of the periodic table of D.I. Mendeleev |last=Fedorova |first=Vera |date=3 March 2017 |website=jinr.ru |publisher=[[Joint Institute for Nuclear Research]] |access-date=4 February 2018}}</ref>"}},
{"article_title": "Heat pump", "pageid": "68316", "revid": "1061640277", "timestamp": "2021-12-22T23:31:58Z", "history_paths": [["Heat pump --- Introduction ---", "History"]], "categories": ["heat pumps", "bright green environmentalism", "building engineering", "energy conversion", "energy recovery", "energy technology", "residential heating"], "heading_tree": {"Heat pump --- Introduction ---": {"Principle of operation": {}, "History": {}, "Types": {"Air source heat pump": {}, "Geothermal (ground-source) heat pump": {}, "Exhaust air heat pump": {}, "Solar-assisted heat pump": {}, "Water source heat pump": {}, "Hybrid heat pump": {}}, "Applications": {"Heating and cooling of buildings and vehicles": {}, "Water heating": {}, "District heating": {}, "Industrial heating": {}}, "Performance": {}, "Operation": {"Refrigerant choice": {}}, "Government incentives": {"United Kingdom": {}, "United States": {"Alternative Energy Credits in Massachusetts": {}}}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Heat pump --- Introduction ---|History": "{{Expand section|date=June 2008}}\n\nMilestones:\n\n* 1748: [[William Cullen]] demonstrates artificial refrigeration.\n* 1834: [[Jacob Perkins]] builds a practical [[refrigerator]] with [[dimethyl ether]].\n* 1852: [[William Thomson, 1st Baron Kelvin|Lord Kelvin]] describes the theory underlying heat pumps.\n* 1855\u20131857: [[Peter von Rittinger]] develops and builds the first heat pump.<ref>{{Cite book|url=http://www.researchandmarkets.com/reports/2174113/an_introduction_to_thermogeology_ground_source.pdf|title=An Introduction to Thermogeology: Ground Source Heating and Cooling|last=Banks|first=David L.|publisher=Wiley-Blackwell|isbn=978-1-4051-7061-1|author-link=David L. Banks|date=2008-05-06|access-date=2014-03-05|archive-date=2016-12-20|archive-url=https://web.archive.org/web/20161220214051/http://www.researchandmarkets.com/reports/2174113/an_introduction_to_thermogeology_ground_source.pdf|url-status=live}}</ref>\n* 1877: In the period before 1875, heat pumps were for the time being pursued for [[Vapor-compression evaporation|vapour compression evaporation]] (open heat pump process) in salt works with their obvious advantages for saving wood and coal. In 1857, Peter von Rittinger was the first to try to implement the idea of vapor compression in a small pilot plant. Presumably inspired by Rittinger's experiments in Ebensee, Antoine-Paul Piccard from the University of Lausanne and the engineer J.H. Weibel from the Weibel-Briquet company in Geneva built the world's first really functioning vapor compression system with a two-stage piston compressor. In 1877 this first heat pump in Switzerland was installed in the [[Bex|Bex salt works]]. <ref name="MaZo-HHP2008">Zogg M.: History of Heat Pumps - Swiss Contributions and International Milestones, Swiss Federal Office of Energy, Berne 2008|online=https://www.aramis.admin.ch/Texte/?ProjectID=45262 {{Webarchive|url=https://web.archive.org/web/20211123223806/https://www.aramis.admin.ch/Texte/?ProjectID=45262 |date=2021-11-23 }}</ref><ref>{{citation|surname1=Wirth E.|title=Aus der Entwicklungsgeschichte der W\u00e4rmepumpe, Schweizerische Bauzeitung 1955, Vol. 73, No. 52, pp 647-650.|language=German|url=https://www.e-periodica.ch/digbib/view?pid=sbz-002:1955:73#3306\n}}</ref>   \n* 1928: [[Aurel Stodola]] constructs a closed loop heat pump (water source from [[Lake Geneva]]) which provides heating for the [[Geneva]] city hall to this day.\n* 1937-1945: During and after the [[World War I|First World War]], Switzerland suffered from heavily difficult energy imports and subsequently expanded its hydropower plants. In the period before and especially during the [[World War II|Second World War]], when neutral Switzerland was completely surrounded by fascist-ruled countries, the coal shortage became alarming again. Thanks to their leading position in energy technology, the Swiss companies [[Sulzer (manufacturer) |Sulzer]], [[Escher Wyss & Cie |Escher Wyss]] and [[Brown, Boveri & Cie|Brown Boveri]] built and put in operation around 35 heat pumps between 1937 and 1945. The main heat sources were lake water, river water, groundwater and waste heat. Particularly noteworthy are the six historic heat pumps from the city of Zurich with heat outputs from 100 kW to 6 MW. An international milestone is the heat pump built by Escher Wyss in 1937/38 to replace the wood stoves in the City Hall of Zurich. To avoid noise and vibrations, a recently developed rotary piston compressor was used. This historic heat pump heated the town hall for 63 years until 2001! Only then it was replaced by a new, more efficient heat pump <ref>Zogg M.: History of Heat Pumps - Swiss Contributions and International Milestones, Proceedings 9th International Energy Agency Heat Pump Conference, Zurich, 20-22 May 2008.|online= https://heatpumpingtechnologies.org/publications/history-of-heat-pumpsswiss-contributions-and-international-milestones-2/ {{Webarchive|url=https://web.archive.org/web/20211118164320/https://heatpumpingtechnologies.org/publications/history-of-heat-pumpsswiss-contributions-and-international-milestones-2/ |date=2021-11-18 }}</ref>,<ref name="MaZo-HHP2008"/>\n* 1945: John Sumner, City Electrical Engineer for [[Norwich]], installs an experimental water-source heat pump fed central heating system, using a neighboring river to heat new Council administrative buildings. Seasonal efficiency ratio of 3.42. Average thermal delivery of 147 kW and peak output of 234 kW.<ref name="auto">{{Cite book|title=Electricity supply in the United Kingdom : a chronology - from the beginnings of the industry to 31 December 1985|date=1987|publisher=The Council|others=Electricity Council.|isbn=978-0851881058|oclc=17343802}}</ref>\n* 1948: Robert C. Webber is credited as developing and building the first ground heat pump.<ref>{{cite book |last1=Banks |first1=David |title=An Introduction to Thermogeology: Ground Source Heating and Cooling |date=August 2012 |publisher=John Wiley & Sons |pages=123 }}</ref>\n* 1951: First large scale installation\u2014the [[Royal Festival Hall]] in London is opened with a [[Coal gas|town gas]]-powered reversible water-source heat pump, fed by [[River Thames|the Thames]], for both winter heating and summer cooling needs.<ref name="auto"/>"}},
{"article_title": "Ocean thermal energy conversion", "pageid": "68498", "revid": "1062453602", "timestamp": "2021-12-28T15:19:58Z", "history_paths": [["Ocean thermal energy conversion --- Introduction ---", "History"]], "categories": ["energy conversion", "renewable energy technology", "marine energy", "power station technology", "oceanographical terminology"], "heading_tree": {"Ocean thermal energy conversion --- Introduction ---": {"History": {}, "Currently operating OTEC plants": {}, "Thermodynamic efficiency": {}, "Power cycle types": {"Closed": {}, "Open": {}, "Hybrid": {}, "Working fluids": {}}, "Land, shelf and floating sites": {"Land-based": {}, "Shelf based": {}, "Floating": {}}, "Political concerns": {}, "Cost and economics": {}, "Some proposed projects": {"Bahamas": {}, "Hawaii": {}, "Hainan": {}, "Japan": {}, "United States Virgin Islands": {}, "Kiribati": {}, "Martinique": {}, "Maldives": {}}, "Related activities": {"Desalination": {}, "Air conditioning": {}, "Chilled-soil agriculture": {}, "Aquaculture": {}, "Hydrogen production": {}, "Mineral extraction": {}, "Climate control": {}}, "Thermodynamics": {"Variation of ocean temperature with depth": {}, "Open/Claude cycle": {}, "Closed Anderson cycle": {}}, "Environmental impact": {"Hydrodynamic modeling": {}, "Biological modeling": {}, "Studies": {}}, "Technical difficulties": {"Dissolved gases": {}, "Microbial fouling": {}, "Sealing": {}, "Parasitic power consumption by exhaust compressor": {}}, "Cold air/warm water conversion": {}, "Application of the thermoelectric effect": {}, "See also": {}, "References": {}, "Sources": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Ocean thermal energy conversion --- Introduction ---|History": "Attempts to develop and refine OTEC technology started in the 1880s. In 1881, [[Jacques Arsene d'Arsonval]], a French [[physicist]], proposed tapping the thermal energy of the ocean. D'Arsonval's student, [[Georges Claude]], built the first OTEC plant, in Matanzas, [[Cuba]] in 1930.<ref>{{Cite journal\n  | last = Chiles\n  | first = Jamesin \n  | title = The Other Renewable Energy\n  | journal = Invention and Technology\n  | volume = 23\n  | issue = 4\n  | pages = 24\u201335\n  | date = Winter 2009\n  }}\n</ref><ref>[https://books.google.com/books?id=qOIDAAAAMBAJ&pg=PA881&dq=Popular+Science+1930+plane+%22Popular+Mechanics%22&hl=en&ei=_7BlTsWeBYTWgQf9mIiLCg&sa=X&oi=book_result&ct=result&resnum=10&sqi=2&ved=0CE8Q6AEwCQ#v=onepage&q&f=true "Power from the Sea" ''Popular Mechanics'', December 1930, pp 881-882] detail article and photos of Cuban power plant</ref> The system generated 22 [[Kilowatt|kW]] of [[electricity]] with a low-[[pressure]] [[turbine]].<ref name="dow-book">{{Cite book|last=Takahashi|first=Masayuki Mac|url=http://www.terrapub.co.jp/e-library/dow/index.html|title=Deep Ocean Water as Our Next Natural Resource|publisher=Terra Scientific Publishing Company|year=2000|isbn=978-4-88704-125-7|location=Tokyo, Japan|translator-last=Kitazawa|translator-first=Kazuhiro|orig-year=1991|translator-last2=Snowden|translator-first2=Paul}}</ref> The plant was later destroyed in a storm.<ref name="Avery, William H 1994">Avery, William H. and Chih Wu. Renewable Energy From the Ocean: A Guide to OTEC.\tNew York: Oxford University Press. 1994.</ref>\n\nIn 1935, Claude constructed a plant aboard a 10,000-[[ton]] cargo vessel moored off the coast of Brazil. Weather and waves destroyed it before it could generate net power.<ref name=dow-book/> (Net power is the amount of power generated after subtracting power needed to run the system).\n\nIn 1956, French scientists designed a 3 [[Megawatt|MW]] plant for [[Abidjan]], [[Ivory Coast]]. The plant was never completed, because new finds of large amounts of cheap petroleum made it uneconomical.<ref name=dow-book/>\n\nIn 1962, J. Hilbert Anderson and James H. Anderson, Jr. focused on increasing component efficiency. They patented their new "closed cycle" design in 1967.<ref name=closed-cycle-patent>{{Ref patent | country = US | number = 3312054 | status = patent | title = Sea Water Power Plant | gdate = 1967-04-04 | fdate = 1966-09-27 | invent1 = J.H. Anderson}}</ref> This design improved upon the original closed-cycle Rankine system, and included this in an outline for a plant that would produce power at lower cost than oil or coal. At the time, however, their research garnered little attention since coal and nuclear were considered the future of energy.<ref name="Avery, William H 1994"/>\n\nJapan is a major contributor to the development of OTEC technology.<ref name=osti-assessment>{{Cite report |title= An Assessment of Research and Development Leadership in Ocean Energy Technologies |date=April 1994| last= Bruch |first= Vicki L. |location= Albuquerque, NM |publisher= Sandia National Laboratories: Energy Policy and Planning Department |id= SAND93-3946 |url= https://www.osti.gov/servlets/purl/10154003 |doi= 10.2172/10154003}}</ref> Beginning in 1970 the [[Tokyo Electric Power Company]] successfully built and deployed a 100 kW closed-cycle OTEC plant on the island of [[Nauru]].<ref name=osti-assessment/>  The plant became operational on 14 October 1981, producing about 120 kW of electricity; 90 kW was used to power the plant and the remaining electricity was used to power a school and other places.<ref name=dow-book/> This set a world record for power output from an OTEC system where the power was sent to a real (as opposed to an experimental) power grid.<ref name=nauru-outline>{{Cite journal | title =  Outline of the 100 kW OTEC Pilot Plant in the Republic of Nauru | vauthors = Mitsui T, Ito F, Seya Y, Nakamoto Y |date=September 1983 | journal = IEEE Transactions on Power Apparatus and Systems | volume = PAS-102 | issue = 9 | pages = 3167\u20133171 |url = http://library.greenocean.org/oteclibrary/otecdesigns/OTEC-nauru.pdf/view | doi = 10.1109/TPAS.1983.318124 |bibcode =1983ITPAS.102.3167M | s2cid = 8924555 |archive-url=https://web.archive.org/web/20080502133042/http://library.greenocean.org/oteclibrary/otecdesigns/OTEC-nauru.pdf/view |archive-date=2008-05-02 |url-status=dead}}</ref> 1981 also saw a major development in OTEC technology when Russian engineer, Dr. Alexander Kalina, used a mixture of ammonia and water to produce electricity. This new ammonia-water mixture greatly improved the efficiency of the power cycle. In 1994 Saga University designed and constructed a 4.5 kW plant for the purpose of testing a newly invented Uehara cycle, also named after its inventor Haruo Uehara. This cycle included\nabsorption and extraction processes that allow this system to outperform the Kalina cycle by 1-2%.<ref>Finney, Karen Anne. "Ocean Thermal Energy Conversion". Guelph Engineering Journal. 2008.</ref> Currently, the Institute of Ocean Energy, Saga University, is the leader in OTEC power plant research and also focuses on many of the technology's secondary benefits.\n\nThe 1970s saw an uptick in OTEC research and development during the post 1973 Arab-Israeli War, which caused oil prices to triple. The U.S. federal government poured $260 million into OTEC research after President Carter signed a law that committed the US to a production goal of 10,000 MW of electricity from OTEC systems by 1999.<ref>{{cite news|last=Daly|first=John|title=Hawaii About to Crack Ocean Thermal Energy Conversion Roadblocks?|url=http://oilprice.com/Alternative-Energy/Renewable-Energy/Hawaii-About-To-Crack-Ocean-Thermal-Energy-Conversion-Roadblocks.html|access-date=28 March 2013|newspaper=OilPrice.com|date=December 5, 2011}}</ref>\n\n[[File:OTEC in Hawaii.jpg|thumb|left|View of a land based OTEC facility at [[Keahole Point]] on the [[Kona District, Hawaii|Kona]] coast of [[Hawaii]]]]\n\nIn 1974, The U.S. established the [[Natural Energy Laboratory of Hawaii Authority]] (NELHA) at [[Keahole Point]] on the [[Kona District, Hawaii|Kona coast]] of [[Hawaii (island)|Hawaii]]. Hawaii is the best US OTEC location, due to its warm surface water, access to very deep, very cold water, and high electricity costs. The laboratory has become a leading test facility for OTEC technology.<ref name=elec-costs>{{cite web | title =  Average Retail Price of Electricity to Ultimate Customers by End-Use Sector, by State | publisher = [[Energy Information Administration]] |date = September 2007| url = http://www.eia.doe.gov/cneaf/electricity/epm/table5_6_a.html}}</ref> In the same year, Lockheed received a grant from the U.S. National Science Foundation to study OTEC. This eventually led to an effort by Lockheed, the US Navy, Makai Ocean Engineering, Dillingham Construction, and other firms to build the world's first and only net-power producing OTEC plant, dubbed "Mini-OTEC"<ref name="lockheed1">{{cite web|author1=L. Meyer |author2=D. Cooper |author3=R. Varley |title=Are We There Yet? A Developer's Roadmap to OTEC Commercialization|url=http://hinmrec.hnei.hawaii.edu/wp-content/uploads/2010/01/OTEC-Road-to-Commercialization-September-2011-_-LM.pdf|website=Hawaii National Marine Renewable Energy Center|access-date=28 March 2013}}</ref> For three months in 1979, a small amount of electricity was generated.\n\nA European initiative EUROCEAN - a privately funded joint venture of 9 European companies already active in offshore engineering - was active in promoting OTEC from 1979 to 1983. Initially a large scale offshore facility was studied. Later a 100 kW land based installation was studied combining land based OTEC with Desalination and Aquaculture nicknamed ODA. This was based on the results from a small scale aquaculture facility at the island of St Croix that used a deepwater supply line to feed the aquaculture basins. Also a shore based open cycle plant was investigated.\nThe location of the case of study was the Dutch Kingdom related island Cura\u00e7ao.<ref>{{cite web | url = https://en.wikipedia.org/wiki/Cura%C3%A7ao | title = Cura\u00e7ao | access-date=28 April 2020}}</ref>{{Circular reference|date=May 2020}}\n\nResearch related to making open-cycle OTEC a reality began earnestly in 1979 at the Solar Energy Research Institute (SERI) with funding from the US Department of Energy. Evaporators and suitably configured direct-contact condensers were developed and patented by SERI (see<ref>Bharathan, D.; Penney, T. R. (1984). Flash Evaporation from Turbulent Water Jets. Journal of Heat Transfer. Vol. 106(2), May 1984; pp. 407-416.</ref><ref>Bharathan, D. (1984). Method and Apparatus for Flash Evaporation of Liquids. U.S. Patent No. 4,474,142.</ref><ref>Bharathan, D.; Parsons, B. K.; Althof, J. A. (1988). Direct-Contact Condensers for Open-Cycle OTEC Applications: Model Validation with Fresh Water Experiments for Structured Packings. 272 pp.; NREL Report No. TR-253-3108.</ref>). An original design for a power-producing experiment, then called the 165-kW experiment was described by [[Frank Kreith|Kreith]] and Bharathan (,<ref>Bharathan, D.; [[Frank Kreith|Kreith, F.]]; Schlepp, D. R.; Owens, W. L. (1984). Heat and Mass Transfer in Open-Cycle OTEC Systems. Heat Transfer Engineering. Vol. 5(1-2); pp. 17-30.</ref> and<ref>Kreith, F.; Bharathan, D. (1988). Heat Transfer Research for Ocean Thermal Energy Conversion. Journal of Heat Transfer. Vol. 110, February 1988; pp. 5-22.</ref>) as the [[Max Jakob Memorial Award]] Lecture. The initial design used two parallel axial turbines, using last stage rotors taken from large steam turbines. Later, a team led by Dr. Bharathan at the National Renewable Energy Laboratory (NREL) developed the initial conceptual design for up-dated 210 kW open-cycle OTEC experiment (<ref>Bharathan, D.; Green, H. J.; Link, H. F.; Parsons, B. K.; Parsons, J. M.; Zangrando, F. (1990). Conceptual Design of an Open-Cycle Ocean Thermal Energy Conversion Net Power-Producing Experiment (OC-OTEC NPPE). 160 pp.; NREL Report No. TR-253-3616.</ref>). This design integrated all components of the cycle, namely, the evaporator, condenser and the turbine into one single vacuum vessel, with the turbine mounted on top to prevent any potential for water to reach it. The vessel was made of concrete as the first process vacuum vessel of its kind. Attempts to make all components using low-cost plastic material could not be fully achieved, as some conservatism was required for the turbine and the vacuum pumps developed as the first of their kind. Later Dr. Bharathan worked with a team of engineers at the Pacific Institute for High Technology Research (PICHTR) to further pursue this design through preliminary and final stages. It was renamed the Net Power Producing Experiment (NPPE) and was constructed at the Natural Energy Laboratory of Hawaii (NELH) by PICHTR by a team led by Chief Engineer Don Evans and the project was managed by Dr. Luis Vega.\n\n[[File:otec2.jpg|thumb|left|[[India]] \u2013 pipes used for OTEC (left) and floating OTEC plant constructed in 2000 (right)]]\n\nIn 2002, India tested a 1 MW floating OTEC pilot plant near Tamil Nadu. The plant was ultimately unsuccessful due to a failure of the deep sea cold water pipe.<ref>Avery, William H. and Chih Wu. Renewable Energy From the Ocean: A Guide to OTEC. New York: Oxford University Press. 1994.</ref> [[Government of India|Its government]] continues to sponsor research.<ref>{{cite web | url = http://www.makai.com/ocean-thermal-energy-conversion/ | title = Deep Pipelines for Ocean Thermal Energy Conversion | access-date=8 January 2020}}</ref>\n\nIn 2006, Makai Ocean Engineering was awarded a contract from the U.S. [[Office of Naval Research]] (ONR) to investigate the potential for OTEC to produce nationally significant quantities of hydrogen in at-sea floating plants located in warm, tropical waters. Realizing the need for larger partners to actually commercialize OTEC, Makai approached Lockheed Martin to renew their previous relationship and determine if the time was ready for OTEC. And so in 2007, Lockheed Martin resumed work in OTEC and became a subcontractor to Makai to support their SBIR, which was followed by other subsequent collaborations<ref name="lockheed1" />\n\nIn March 2011, Ocean Thermal Energy Corporation signed an Energy Services Agreement (ESA) with the Baha Mar resort, Nassau, Bahamas, for the world's first and largest seawater air conditioning (SWAC) system.<ref>{{cite web|url=http://otecorporation.com/2011/12/19/baha-mar-resort-signs-energy-services-agreement-with-ote-corporation/|title=Baha Mar Resort Signs Energy Services Agreement with OTE Corporation|last=Spaine |date=19 December 2011}}</ref> In June 2015, the project was put on pause while the resort resolved financial and ownership issues.<ref>{{cite web|url=https://www.forbes.com/sites/erincarlyle/2015/06/29/baha-mar-resorts-to-chapter-11-bankruptcy-blames-china-construction-for-delays/|title=Baha Mar Resorts To Chapter 11 Bankruptcy, Blames China Construction For Delays|first=Erin|last=Carlyle|website=Forbes}}</ref> In August 2016, it was announced that the issues had been resolved and that the resort would open in March 2017.<ref name="otecorporation.com">http://otecorporation.com/2016/08/30/ocean-thermal-energy-corporation-reports-announcement-bahamian-government-remobilization-completion-opening-baha-mar-beach-resort/</ref> It is expected that the SWAC system's construction will resume at that time.\n\nIn July 2011, Makai Ocean Engineering completed the design and construction of an OTEC Heat Exchanger Test Facility at the [[Natural Energy Laboratory of Hawaii]]. The purpose of the facility is to arrive at an optimal design for OTEC heat exchangers, increasing performance and useful life while reducing cost (heat exchangers being the #1 cost driver for an OTEC plant).<ref>{{cite web|title=Makai Ocean Engineering's Heat Exchanger Test Facility opened|url=http://www.otecnews.org/2011/11/makai-ocean-engineerings-heat-exchanger-test-facility-opened/|website=www.otecnews.org|access-date=28 March 2013|date=2011-11-22}}</ref> And in March 2013, Makai announced an award to install and operate a 100 kilowatt turbine on the OTEC Heat Exchanger Test Facility, and once again connect OTEC power to the grid.<ref>{{cite web|title=Makai Ocean Engineering working with Navy on Big Island OTEC project|url=http://www.bizjournals.com/pacific/news/2013/03/19/makai-ocean-engineering-working-with.html|access-date=28 March 2013}}</ref><ref>{{cite web |title=Makai Ocean Engineering to add 100kW turbine generator to Kona, Hawaii OTEC test facility |url=http://www.districtenergy.org/blog/2013/03/19/makai-ocean-engineering-to-add-100kw-turbine-generator-to-kona-hawaii-otec-test-facility/ |website=International District Energy Association |access-date=2013-03-28 |archive-url=https://web.archive.org/web/20141110122515/http://www.districtenergy.org/blog/2013/03/19/makai-ocean-engineering-to-add-100kw-turbine-generator-to-kona-hawaii-otec-test-facility/ |archive-date=2014-11-10 |url-status=dead }}</ref>\n\nIn July 2016, the Virgin Islands Public Services Commission approved Ocean Thermal Energy Corporation's application to become a Qualified Facility. The company is thus permitted to begin negotiations with the Virgin Islands Water and Power Authority (WAPA) for a Power Purchase Agreement (PPA) pertaining to an Ocean Thermal Energy Conversion (OTEC) plant on the island of St. Croix. This would be the world's first commercial OTEC plant.<ref name="ReferenceA">{{Cite web|url=http://otecorporation.com/2016/07/18/ote-receives-approval-otec-system-usvi/|title = OTE Receives Approval for OTEC System in the USVI|date = 18 July 2016}}</ref><ref name="lancasteronline.com">{{cite web|url=https://lancasteronline.com/business/local_business/ocean-thermal-to-begin-talks-for-renewable-energy-plants-in/article_e68b41f4-4da4-11e6-8d72-1352558baa6f.html|title=Ocean Thermal to begin talks for renewable energy plants in St. Croix, St. Thomas |first=Tim |last=Mekeel |website=LancasterOnline}}</ref>"}},
{"article_title": "Alarm device", "pageid": "68630", "revid": "1060815650", "timestamp": "2021-12-17T21:02:15Z", "history_paths": [["Alarm device --- Introduction ---", "History and development"]], "categories": ["security technology", "alarms", "warning systems"], "heading_tree": {"Alarm device --- Introduction ---": {"Etymology": {}, "History and development": {}, "Responses to an alarm": {}, "False alarms": {}, "Devices": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Alarm device --- Introduction ---|History and development": "Early alarm devices were often [[bell]]s, [[drums]], other musical instruments, or any items which made unusual loud noises that attracted the attention of the surrounding population.\n\nWhistles were used by police in the 19th century. [[Steam whistle]]s have been used on locomotives, ships, and in factories as alarm devices.\n\nWith the advent of electricity, a variety of other alerting devices have been invented, such as [[buzzer]]s, [[klaxon]]s, [[siren (alarm)|sirens]], [[horn (acoustic)|horns]], flashing and coloured lights, and other all-purpose alarms.\n\nAlarm devices can be fitted to buildings as well as vehicles. Many buildings are fitted with [[Fire alarm system|fire alarms]], ranging from a self-contained domestic [[smoke detector]] to a sophisticated alarm system that can operate building fire fighting systems automatically to extinguish fires with water or inert gases.\n\nMany industries have developed standards for alarm devices, and the colours red, blue and amber are generally recognized as alarm device-related colours, with flashing lights often indicating urgent conditions."}},
{"article_title": "Fruit press", "pageid": "68869", "revid": "1030024851", "timestamp": "2021-06-23T12:14:55Z", "history_paths": [["Fruit press --- Introduction ---", "History"]], "categories": ["oenology", "flavor technology"], "heading_tree": {"Fruit press --- Introduction ---": {"History": {}, "Cider press": {}, "Wine press": {}, "Oil press": {}, "DIY fruit press": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Fruit press --- Introduction ---|History": "In the United States, [[Madeline Turner]] invented the Turner's Fruit-Press, in 1916.<ref name=CSU1>{{cite web|title=Madeline M. Turner|url=http://www.csupomona.edu/~plin/inventors/turner.html|work=Food Production and Processing|publisher=[[California State University]]|access-date=20 March 2014|url-status=dead|archive-url=https://web.archive.org/web/20130612173854/http://www.csupomona.edu/~plin/inventors/turner.html|archive-date=12 June 2013}}</ref><ref name="Foy2012">{{cite book|author=David M. Foy|title=Great Discoveries and Inventions by African-Americans: Fourth Edition|url=https://books.google.com/books?id=KMxbrg8uv-oC&pg=PA85|date=2 February 2012|publisher=AuthorHouse|isbn=978-1-4685-2435-2|page=85}}</ref>"}},
{"article_title": "FSO Syrena", "pageid": "69206", "revid": "1051423298", "timestamp": "2021-10-23T12:24:05Z", "history_paths": [["FSO Syrena --- Introduction ---", "History"]], "categories": ["fso vehicles", "science and technology in poland", "cars introduced in 1957", "1960s cars", "1970s cars", "1980s cars", "front-wheel-drive vehicles", "sedans"], "heading_tree": {"FSO Syrena --- Introduction ---": {"History": {"Syrena 100": {}, "Syrena 101": {}, "Syrena 102": {}, "Syrena 103": {}, "Syrena 104": {}, "Syrena 105": {}}, "{{anchor|Bosto}} Syrena Bosto": {"Dimensions": {}}, "Syrena Sport": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"FSO Syrena --- Introduction ---|History": "At first, Polish engineers wanted Syrena to have a four-stroke air-cooled engine and a self-supporting chassis. But due to a lack of [[Deep drawing|deep-drawn]] metal parts and cost reductions, the first Syrena 100 cars were supposed to have a wooden bodywork covered with leather-like material. The cars were powered by 2-stroke engines designed by engineer [[Fryderyk Bluemke]]. The first two prototypes of Syrena were made in December 1953. One \u2013 with a wooden framework, was constructed by [[Stanislaw Panczakiewicz]], while the second, steel-bodied car was made by [[Stanislaw Lukaszewicz]]. They met halfway by combining the first car's design with the steel bodywork of the second one (with one exception \u2013 the roof remained wooden). By March 1955 FSO had built 5 prototypes of Syrena 100.\n\nIn September all of the prototypes took part in an experimental rally covering a distance of 5600 km. One of the cars, driven by Karol Pionnier, crashed, revealing the weak structure of the roof. As a result, the engineers decided to use steel instead of wood for this part of the car. One of the prototypes was exhibited at the Pozna\u0144 Trade Fair in autumn 1955. On 20 March 1957 the mass production of Syrena 100 started.\n{{clear}}\n\n [[File:Syrena.jpg|thumb|Syrena 100]]\n\nSyrena 100 was designed by engineers Stanislaw Lukasiewicz, Stanislaw Panczakiewicz and Fryderyk Bluemke. It was introduced to the public in June 1955 at the 24th Pozna\u0144 Trade Fair. The car aroused much interest, which prompted the government to put it into production. At first, the production rate was to be 10,000 cars a year. Because of financial reasons, Syrena 100 and the much larger [[FSO Warszawa|Warszawa automobile]] shared many parts. As a result, the Syrena was much heavier than intended (950 kg).\n{{clear}}\n\n [[File:FSO Syrena 101 in Muzeum In\u017cynierii Miejskiej in Krak\u00f3w (2).JPG|thumb|Syrena 101]]\nIn 1960 Syrena underwent a first, minor modernisation. The improved car had a pneumatic [[Fuel pump (engine)|fuel pump]] and a different type of [[carburetor]]. It also received new twin [[windscreen wiper]]s and a better suspension.\n{{clear}}\n\n [[File:Syrena 102.jpg|thumb|right|Syrena 102]]\nThe Syrena 102, produced in 1962 and 1963, had slightly different body details. The "S" version of this model shared an engine with [[Wartburg_311#Wartburg_312|Wartburg 312]]. Around 150 examples of Syrena 102S were produced.\n{{clear}}\n\n [[File:FSO Syrena 103.JPG|thumb|right|Syrena 103 - original painting]]\nSyrena 103 (1963\u201366) had a restyled front and a different engine.\n{{clear}}\n\n [[File:Syrena 104.JPG|thumb|Syrena 104]]\nThe next model lasted from 1966 to 1972. It had a new, three-cylinder engine, a [[Manual transmission#Synchromesh|synchronized gearbox]] and restyled tail lights.\n{{clear}}\n\n [[File:FSM Syrena 105 at the Muzeum In\u017cynierii Miejskiej in Krak\u00f3w (2).JPG|thumb|left|FSM Syrena 105]]\nThe 105 was the last Syrena design.<ref name=abc>{{ cite web | url = http://www.abc.se/~m9805/eastcars/syrena/history.html | archive-url = https://web.archive.org/web/20200316105254/https://www.abc.se/~m9805/eastcars/syrena/history.html | archive-date = 2020-03-16 | title = History of Syrena | work = Kent Ekholms webbsidor | first = J\u00eadrzej | last = Lubicz }}</ref> It was produced from 1972 to 1983 by the [[Fabryka Samochod\u00f3w Ma\u0142olitra\u017cowych|FSM factory]] and was badged accordingly.<ref name=abc/> Unlike its predecessors it had regular front doors instead of [[suicide door|"suicide"]] ones. The "Lux" version, produced from 1974, had the gear lever and handbrake between the front seats. The 105 served as a basis for two other models \u2013 Syrena R-20, which was a pick-up and a van \u2013 Bosto.\n\n[[File:FSM Syrena R20 z 1981 roku.jpg|thumb|1981 FSM Syrena R-20]]\nA 1983 FSM Syrena 105L finished in [[yellow]] was featured in series 10 episode 10 of the [[Great Britain|British]] [[television]] program ''[[Wheeler Dealers]]''.  Presenter [[Mike Brewer (television presenter)|Mike Brewer]] purchased the car in Poland for [[Polish z\u0142oty|z\u0142]]7,000 (the equivalent of [[Pound sterling|\u00a3]]1,400) and drove it back to the show's UK-based workshop where it underwent repairs and upgrades by mechanic [[Edd China]]. The colour was changed to red and white in homage to the Polish flag. Other work included upgrades to the steering box, refurbishing the drum brakes, replacing the dynamo with an alternator and replacing the radio. The total cost of procuring and upgrading the car reached \u00a35454. The completed car was driven to the Polish embassy where ambassador [[Witold Sobk\u00f3w]] took a ride with them. The car was later sold for \u00a38,000 to the [[bubble car]] museum in [[Lincolnshire]].\n\n{{clear}}"}},
{"article_title": "Delta Works", "pageid": "69398", "revid": "1057144348", "timestamp": "2021-11-25T18:44:07Z", "history_paths": [["Delta Works --- Introduction ---", "History"]], "categories": ["delta works", "rhine\u2013meuse\u2013scheldt delta", "dikes in the netherlands", "dams in the netherlands", "flood control in the netherlands", "water resource management in the netherlands", "science and technology in the netherlands"], "heading_tree": {"Delta Works --- Introduction ---": {"History": {"Delta law and conceptual framework": {}, "Alterations to the plan during the execution of the Works": {"The storm-surge barrier": {}, "Environmental policy implementations": {}}}, "Environmental effects": {}, "Project costs": {}, "Current status": {}, "Projects": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Delta Works --- Introduction ---|History": "The [[estuary|estuaries]] of the rivers [[Rhine]], [[Meuse]] and [[Schelde]] have been subject to flooding over the centuries. After building the [[Afsluitdijk]] (1927{{snd}}1932), the Dutch started studying the damming of the [[Rhine\u2013Meuse\u2013Scheldt delta|Rhine-Meuse Delta]]. Plans were developed to shorten the coastline and turn the delta into a group of freshwater [[coastal reservoir|coastal lakes]]. By shortening the coastline, fewer dikes would have to be reinforced.\n\nDue to indecision and the [[World War II|Second World War]], little action was taken. In 1950 two small estuary mouths, the Brielse Gat near [[Brielle]] and the Botlek near [[Vlaardingen]] were dammed. After the [[North Sea flood of 1953]], a Delta Works Commission was installed to research the causes and develop measures to prevent such disasters in future. They revised some of the old plans and came up with the "Deltaplan".\n\nUnlike the Zuiderzee Works, the Delta Plan's purpose is largely defensive and not for [[land reclamation]].<ref name="ley196110">{{cite magazine |last=Ley |first=Willy |date=October 1961 |title=The Home-Made Land |department=For Your Information |url=https://archive.org/stream/Galaxy_v19n06_1961-08#page/n65/mode/1up |magazine=Galaxy Science Fiction |pages=92\u2013106 }}</ref> The Delta Plan is a national programme and demands collaboration between the national government, provincial authorities, municipal authorities and the water boards. The plan consisted of blocking the estuary mouths of the [[Oosterschelde]], the [[Haringvliet]] and the [[Grevelingen]]. This reduced the length of the dikes exposed to the sea by {{Convert|700|km|mi}}. The mouths of the [[Nieuwe Waterweg]] and the [[Westerschelde]] were to remain open because of the important shipping routes to the ports of [[Rotterdam]] and [[Port of Antwerp|Antwerp]]. The dikes along these waterways were to be heightened and strengthened. The works would be combined with road and waterway infrastructure to stimulate the economy of the province of [[Zeeland]] and improve the connection between the ports of Rotterdam and Antwerp.\n\n [[File:Colijnsplaat - Zeelandbr\u00fccke.jpg|thumb|[[Zeeland Bridge]]]]\n[[File:OosterscheldeKering.jpg|thumb|[[Oosterscheldekering]]]]\n\nAn important part of this project was fundamental research to come up with long term solutions, protecting the Netherlands against future floods. Instead of analysing past floods and building protection sufficient to deal with those, the Delta Works commission pioneered a conceptual framework to use as norm for investment in flood defences.\n\nThe framework is called the 'Delta norm'; it includes the following principles:\n* Major areas to be protected from flooding are identified. These are called "dike ring areas" because they are protected by a ring of primary sea defences.\n* The cost of flooding is assessed using a statistical model involving damage to property, lost production, and a given amount per human life lost.\n* For the purpose of this model, a human life is valued at \u20ac2.2 million (2008 data).\n* The chances of a significant flood within the given area are calculated. This is done using data from a purpose-built flood simulation lab, as well as empirical statistical data regarding water wave properties and distribution. Storm behaviour and spring tide distribution are also taken into account.\n\nThe most important "dike ring area" is the South Holland coast region. It is home to four million people, most of whom live below normal sea level. The loss of human life in a catastrophic flood here can be very large because there is typically little warning time with North Sea storms. Comprehensive evacuation is not a realistic option for the Holland coastal region.\n\nThe commission initially set the acceptable risk for complete failure of every "dike ring" in the country at 1 in 125,000 years. But, it found that the cost of building to this level of protection could not be supported. It set "acceptable" risks by region as follows:\n\n* North and South Holland (excluding Wieringermeer): 1 per 10,000 years\n* Other areas at risk from sea flooding: 1 per 4,000 years\n* Transition areas between high land and low land: 1 per 2,000 years\n\nRiver flooding causes less damage than salt water flooding, which causes long-term damage to agricultural lands. Areas at risk from river flooding were assigned a higher acceptable risk. River flooding also has a longer warning time, producing a lower estimated death toll per event.\n\n* South Holland at risk from river flooding: 1 per 1,250 years\n* Other areas at risk from river flooding: 1 per 250 years.\n\nThese acceptable risks were enshrined in the Delta Law (Dutch: ''Deltawet''). This required the government to keep risks of catastrophic flooding within these limits and to upgrade defences should new insights into risks require this. The limits have also been incorporated into the new Water Law (''Waterwet''), effective from 22 December 2009.\n\nThe Delta Project (of which the Delta Works are a part) has been designed with these guidelines in mind. All other primary defences have been upgraded to meet the norm. New data elevating the risk assessment on expected [[sea level rise]] due to global warming has identified ten 'weak points.' These have been upgraded to meet future demands. The latest upgrades are made under the High Water Protection Program.\n\n [[File:Schaalmodel Maeslantkering.jpg|thumb|Scale model of the [[Maeslantkering]]]]\nDuring the execution of the works, changes were made in response to public pressure. In the Nieuwe Waterweg, the heightening and the associated widening of the dikes proved very difficult because of public opposition to the planned destruction of important historic buildings to achieve this. The plan was changed to the construction of a storm surge barrier (the [[Maeslantkering]]) and dikes were only partly built up.\n\n The Delta Plan originally intended to create a large freshwater lake, the ''{{lang|nl|Zeeuwse Meer}}'' (Zeeland Lake).{{r|ley196110}} This would have caused major environmental destruction in Oosterschelde, with the total loss of the saltwater ecosystem and, consequently, the harvesting of oysters. Environmentalists and fishermen combined their efforts to prevent the closure; they persuaded parliament to amend the original plan. Instead of completely damming the estuary, the government agreed to build a storm surge barrier. This essentially is a long collection of very large valves that can be closed against storm surges.\n\nThe storm surge barrier closes only when the sea-level is expected to rise 3 metres above mean sea level. Under normal conditions, the estuary's mouth is open, and salt water flows in and out with the tide. As a result of the change, the weak dikes along the Oosterschelde needed to be strengthened. Over 200 km of the dike needed new revetments. The connections between the Eastern Scheldt and the neighboring [[Haringvliet]] had to be dammed to limit the effect of the salt water. Extra dams and locks were needed at the east part of the Oosterschelde to create a shipping route between the ports of Rotterdam and Antwerp. Since operating the barrier has an effect on the environment, fisheries and the water management system, decisions made on opening or closing the gate are carefully considered. Also the safety of the surrounding dykes are affected by barrier operations.\n\n In an attempt to restore and preserve the natural system surrounded by the dykes and storm-surge barrier, the concept 'building with nature' was introduced in revised Delta Program updates after 2008. The new integrated water management plan not only takes into account protection against flooding, but also covers water quality, leisure industry, economic activities, shipping, environment and nature. Whenever possible, existing engineering constructions would be replaced by more 'nature friendly' options in an attempt to restore natural estuary and tides, while still protecting against flooding.<ref>{{cite journal|last1=Kabat|first1=Pavel|last2=Fresco|first2=Louise|last3=Stive|first3=Marcel J.F.|last4=Veerman|first4=Cees P.|last5=van Alphen|first5=Jos S.L.J.|last6=Parmet|first6=Bart W. A. H.|last7=Hazeleger|first7=Wilco|last8=Katsman|first8=Caroline A.|title=Dutch coasts in transition|journal=Nature Geoscience|date=July 2009|volume=2|issue=7|pages=450\u2013451|doi=10.1038/ngeo572|bibcode=2009NatGe...2..450K}}</ref> In addition, building components of the reinforcements are designed in a way that they support formation of entire ecosystems.<ref>{{cite journal|last1=Deltares|title=Bouwen met de natuur in de praktijk|journal=Delta Life|date=2014|volume=1|pages=14\u201315}}</ref> As part of the revision, the [[Room for the River (Netherlands)|Room for the River]] projects, enabled nature to occupy space by lowering or widening the river bed.<ref>{{cite journal|last1=Van Buuren|first1=A|last2=Ellen|first2=G.J.|last3=Warner|first3=J.F.|title=Path-dependency and policy learning in the Dutch delta: toward more resilient flood risk management in the Netherlands?|journal=Ecology and Society|date=2016|volume=21|issue=4|doi=10.5751/es-08765-210443}}</ref> In order to establish this, agricultural flood plains are turned into natural parks, excavated farmland is used for wild vegetation and newly excavated lakes and bypasses create habitats for fish and birds.<ref>{{cite journal|last1=Rijcken|first1=Ties|title=A critical approach to some new ideas about the Dutch flood risk system|journal=Research in Urbanism Series|date=2015|volume=3|issue=1}}</ref> Along the coast, natural sand is added each year to allow sand to blow freely through the dunes instead of having the dunes held in place by planted vegetation or revetments.<ref>{{cite web|last1=DGW|title=Nationaal Waterplan|website=rijksoverheid.nl |url=https://www.rijksoverheid.nl/documenten/rapporten/2009/12/01/nationaal-waterplan-2009-2015|publisher=Ministerie van Infrastructuur en Milieu}}</ref> Although the new plan brought along additional cost, it was received favourably.{{citation needed|date=November 2018}} The re-considerations of the Delta Project indicated the growing importance of integrate environmental impact assessments in policy-making."}},
{"article_title": "Nuclear pulse propulsion", "pageid": "69937", "revid": "1060994594", "timestamp": "2021-12-19T00:04:31Z", "history_paths": [["Nuclear pulse propulsion --- Introduction ---", "History"]], "categories": ["emerging technologies", "nuclear spacecraft propulsion", "plasma physics"], "heading_tree": {"Nuclear pulse propulsion --- Introduction ---": {"History": {"Los Alamos": {}, "Project Orion": {}, "Project Daedalus": {}, "''Medusa''": {}, "Project Longshot": {}, "Antimatter-catalyzed nuclear reaction": {}, "Magneto-inertial fusion": {}, "Pulsed fission-fusion propulsion": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Nuclear pulse propulsion --- Introduction ---|History": "{{Main|Los Alamos Scientific Laboratory}}\n\nCalculations for a potential use of this technology were made at the laboratory from and toward the close of the 1940s to the mid 1950s.<ref>{{cite journal |last1=Nance |first1=JC|title=NUCLEAR-PULSE PROPULSION\u2014II |url=https://nyaspubs.onlinelibrary.wiley.com/doi/abs/10.1111/j.1749-6632.1966.tb50975.x|access-date=2 July 2021|journal= Annals of the New York Academy of Sciences|date=December 1966 |volume=140 |issue=1|pages=396\u2013406|doi=10.1111/j.1749-6632.1966.tb50975.x|bibcode=1966NYASA.140..396N|s2cid=85148140|archive-url= |archive-date= |url-status=live |quote=Research discussed in this paper was sponsored by Air Force Special Weapons Center, Kirtland Air Force Base, New Mexico, Air Force Systems Command, USAF, under Contract AF29(601)-6214. }}</ref>\n\n {{Main|Project Orion (nuclear propulsion)}}\n[[File:Orion pulse unit.png|thumb| A nuclear pulse propulsion unit. The explosive charge [[radiation implosion|ablatively vaporizes]] the propellant, propelling it away from the charge, and simultaneously creating a plasma out of the propellant. The propellant then goes on to impact the pusher plate at the bottom of the Orion spacecraft, imparting a pulse of 'pushing' energy.]]\n\nProject Orion was the first serious attempt to design a nuclear pulse rocket. A design was formed at [[General Atomics]] during the late 1950s and early 1960s, with the idea of reacting small directional nuclear explosives utilizing a variant of the [[Teller\u2013Ulam]] two-stage bomb design against a large steel pusher plate attached to the spacecraft with shock absorbers. Efficient directional explosives maximized the momentum transfer, leading to [[specific impulse]]s in the range of 6,000 seconds, or about thirteen times that of the [[Space Shuttle main engine]]. With refinements a theoretical maximum of 100,000 seconds (1 MN\u00b7s/kg) might be possible. Thrusts were in the millions of [[ton]]s, allowing spacecraft larger than 8{{e|6}} tons to be built with 1958 materials.<ref name="GeneralDynamics1964NuclearPulseVehicleCondensed">{{cite web| url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19760065935_1976065935.pdf| title=Nuclear Pulse Vehicle Study Condensed Summary Report (General Dynamics Corp.)|date=January 1964| author=[[General Dynamics]] Corp.| publisher=U.S. Department of Commerce National Technical Information Service| access-date=December 24, 2008}}</ref>\n\nThe [[reference design]] was to be constructed of steel using submarine-style construction with a crew of more than 200 and a vehicle takeoff weight of several thousand [[ton]]s. This single-stage reference design would reach Mars and return in four weeks from the Earth's surface (compared to 12 months for NASA's current chemically powered reference mission). The same craft could visit Saturn's moons in a seven-month mission (compared to chemically powered missions of about nine years). Notable engineering problems that occurred were related to crew shielding and pusher-plate lifetime. \n\nAlthough the system appeared to be workable, the project was shut down in 1965, primarily because the [[Partial Test Ban Treaty]] made it illegal; in fact, before the treaty, the US and Soviet Union had already  separately detonated a combined number of at least nine nuclear bombs, including thermonuclear, in space, i.e., at altitudes of over 100 km (see [[high-altitude nuclear explosion]]s). [[nuclear ethics|Ethical]] issues complicated the launch of such a vehicle within the Earth's [[magnetosphere]]: calculations using the (disputed) [[linear no-threshold model]] of radiation damage showed that the [[fallout]] from each takeoff would cause the death of approximately 1 to 10 individuals.<ref>{{Cite book|last=Dyson|first=George|url=https://www.worldcat.org/oclc/51109229|title=Project Orion : the atomic spaceship, 1957-1965|date=2003|publisher=Penguin|isbn=0-14-027732-3|location=London|oclc=51109229}}</ref> In a threshold model, such extremely low levels of thinly distributed radiation would have no associated ill-effects, while under [[hormesis]] models, such tiny doses would be negligibly beneficial.<ref>{{Cite journal| author = Heyes| display-authors = etal| title = Authors' reply| date = 1 October 2006| url = http://bjr.birjournals.org/cgi/content/citation/79/946/855| access-date =27 March 2008| doi = 10.1259/bjr/52126615| journal = British Journal of Radiology| volume = 79| issue = 946| pages = 855\u2013857}}</ref><ref>{{Cite journal| author = Aurengo| display-authors = etal| title = Dose-effect relationships and estimation of the carcinogenic effects of low doses of ionizing radiation| publisher = Acad\u00e9mie des Sciences & Acad\u00e9mie nationale de M\u00e9decine| date = 30 March 2005| url = http://www.radscihealth.org/rsh/Papers/FrenchAcadsFinal07_04_05.pdf| access-date = 27 March 2008| url-status = dead| archive-url = https://web.archive.org/web/20110725061127/http://www.radscihealth.org/rsh/Papers/FrenchAcadsFinal07_04_05.pdf| archive-date = 25 July 2011}}</ref> The use of less efficient [[Nuclear weapon design#Clean bombs|clean nuclear bombs]] for achieving orbit and then more efficient, higher yield [[Dirty bomb#Other uses of the term|dirtier bombs]] for travel would significantly reduce the amount of fallout caused from an Earth-based launch.\n\n{{Anchor|deflect2016-01-30}}One useful mission would be to deflect an asteroid or comet on collision course with the Earth, depicted dramatically in the 1998 film ''[[Deep Impact (film)|Deep Impact]]''. The high performance would permit even a late launch to succeed, and the vehicle could effectively transfer a large amount of [[kinetic energy]] to the asteroid by simple impact.<ref>{{cite journal|last=Solem|first=J. C.|year=1994|title=Nuclear explosive propelled interceptor for deflecting objects on collision course with Earth|journal=Journal of Spacecraft and Rockets |volume=31 |issue=4 |pages=707\u2013709 |bibcode=1994JSpRo..31..707S |doi=10.2514/3.26501}}</ref> The prospect of an imminent asteroid impact would obviate concerns over the few predicted deaths from fallout. An automated mission would remove the challenge of designing a shock absorber that would protect the crew.\n\nOrion is one of very few interstellar space drives that could theoretically be constructed with available technology, as discussed in a 1968 paper, "Interstellar Transport" by [[Freeman Dyson]].\n\n {{Main|Project Daedalus}}\nProject Daedalus was a study conducted between 1973 and 1978 by the [[British Interplanetary Society]] (BIS) to design an interstellar unmanned spacecraft that could reach a nearby star within about 50 years. A dozen scientists and engineers led by [[Alan Bond (engineer)|Alan Bond]] worked on the project. At the time [[nuclear fusion|fusion]] research appeared to be making great strides, and in particular, [[inertial confinement fusion]] (ICF) appeared to be adaptable as a rocket engine.\n\nICF uses small pellets of fusion fuel, typically [[Lithium hydride#Lithium deuteride|lithium deuteride]] (<sup>6</sup>Li<sup>2</sup>H) with a small [[deuterium]]/[[tritium]] trigger at the center. The pellets are thrown into a reaction chamber where they are hit on all sides by [[laser]]s or another form of beamed energy. The heat generated by the beams explosively compresses the pellet to the point where fusion takes place. The result is a hot [[Plasma (physics)|plasma]], and a very small "explosion" compared to the minimum size bomb that would be required to instead create the necessary amount of fission.\n\nFor Daedalus, this process was to be run within a large [[electromagnet]] that formed the rocket engine. After the reaction, ignited by electron beams, the magnet funnelled the hot gas to the rear for thrust. Some of the energy was diverted to run the ship's systems and engine. In order to make the system safe and energy efficient, Daedalus was to be powered by a [[helium-3]] fuel collected from [[Jupiter]].\n\n [[File:MedusaNuclearPropulsionConceptDrawing.png|thumb|left|upright=1.36|Conceptual diagram of a Medusa propulsion spacecraft, showing: '''(A)''' the payload capsule, '''(B)''' the winch mechanism, '''(C)''' the optional main tether cable, '''(D)''' riser tethers, and '''(E)''' the parachute mechanism.]]\n[[File:MedusaNuclearPropulsionOperatingSequenceDrawing.png|thumb|right|Operating sequence of the ''Medusa'' propulsion system. This diagram shows the operating sequence of a ''Medusa'' propulsion spacecraft '''(1)''' Starting at moment of explosive-pulse unit firing, '''(2)''' As the explosive pulse reaches the parachute canopy, '''(3)''' Pushes the canopy, accelerating it away from the explosion as the spacecraft plays out the main tether with the winch, generating electricity as it extends, and accelerating the spacecraft, '''(4)''' And finally winches the spacecraft forward to the canopy and uses excess electricity for other purposes.]]\n\nThe ''Medusa'' design has more in common with [[solar sail]]s than with conventional rockets. It was envisioned by [[Johndale Solem]]<ref>{{cite book|last=Gilster|first=Paul|title=Centauri Dreams: Imagining and Planning Interstellar Exploration |publisher=Copernicus Books, Atlanta Book Company|year=2004|isbn=978-0387004365|page=86|url={{google books |plainurl=y |id=57HbBwAAQBAJ|page=86}}}}</ref> in the 1990s and published in the ''[[Journal of the British Interplanetary Society]]'' (JBIS).<ref>{{Cite journal|last=Solem|first=J. C.|title=Medusa: Nuclear explosive propulsion for interplanetary travel|journal=Journal of the British Interplanetary Society|volume=46|number=1|pages=21\u201326|date=January 1993 |bibcode=1993JBIS...46R..21S|issn=0007-084X}}</ref>\n\nA ''Medusa'' spacecraft would deploy a large sail ahead of it, attached by independent cables, and then launch nuclear explosives forward to detonate between itself and its sail. The sail would be accelerated by the plasma and photonic impulse, running out the tethers as when a fish flees a fisher, generating electricity at the "reel". The spacecraft would use some of the generated electricity to reel itself up towards the sail, constantly smoothly accelerating as it goes.<ref>{{cite journal|last=Solem|first=J. C.|title=Nuclear explosive propulsion for interplanetary travel: Extension of the ''Medusa'' concept for higher specific impulse|journal=Journal of the British Interplanetary Society |volume=47|number=6|pages=229\u2013238|date=June 1994|bibcode=1994JBIS...47..229S |issn=0007-084X}}</ref>\n\nIn the original design, multiple tethers connected to multiple motor generators. The advantage over the single tether is to increase the distance between the explosion and the tethers, thus reducing damage to the tethers.\n\nFor heavy payloads, performance could be improved by taking advantage of lunar materials, for example, wrapping the explosive with lunar rock or water, stored previously at a stable [[Lagrangian point|Lagrange point]].<ref>{{Cite journal|last=Solem|first=J. C.|title=The Moon and the Medusa: Use of Lunar Assets in Nuclear-Pulse-Propelled Space Travel |journal=Journal of the British Interplanetary Society|volume=53|number=1|pages=362\u2013370|date=2000|url=http://www.jbis.org.uk/paper.php?p=2000.53.362|bibcode=2000JBIS...53..362S}}</ref>\n\n''Medusa'' performs better than the classical Orion design because its sail intercepts more of the explosive impulse, its shock-absorber stroke is much longer, and its major structures are in tension and hence can be quite lightweight. ''Medusa''-type ships would be capable of a [[specific impulse]] between 50,000 and 100,000 seconds (500 to 1000 kN\u00b7s/kg).\n\n''Medusa'' became widely known to the public in the BBC documentary film [[To Mars By A-Bomb (film)|''To Mars By A-Bomb: The Secret History of Project Orion'']].<ref>{{Citation|last=Sykes|first=Christopher|title=To Mars by A-Bomb: The Secret History of Project Orion|date=2003-03-26|url=https://www.imdb.com/title/tt1039992/|type=Documentary|others=Jaromir Astl, Jeremy Bernstein, Arthur C. Clarke, Ed Creutz|publisher=British Broadcasting Corporation |access-date=2021-06-04}}</ref> A short film shows an artist's conception of how the ''Medusa'' spacecraft works "by throwing bombs into a sail that's ahead of it".<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/mT4ZdPRADEw Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20141016072034/http://www.youtube.com/watch?v=mT4ZdPRADEw Wayback Machine]{{cbignore}}: {{Citation|title=The Medusa: An advanced nuclear pulse spacecraft|url=https://www.youtube.com/watch?v=mT4ZdPRADEw|language=en|access-date=2021-06-04|last=Stevens|first= Nick|year=2014}}{{cbignore}}</ref>\n\n {{Main|Project Longshot}}\nProject Longshot was a [[NASA]]-sponsored research project carried out in conjunction with the [[US Naval Academy]] in the late 1980s.<ref>{{cite web |last=Beals |first=Keith A. |display-authors=etal  |title=Project Longshot An Unmanned Probe To Alpha Centauri|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19890007533_1989007533.pdf |publisher=[[NASA]] |access-date=March 14, 2011}}</ref> ''Longshot'' was in some ways a development of the basic Daedalus concept, in that it used magnetically funneled ICF. The key difference was that they felt that the reaction could not power both the rocket and the other systems, and instead included a 300 kW conventional [[nuclear reactor]] for running the ship. The added weight of the reactor reduced performance somewhat, but even using [[Lithium hydride|LiD]] fuel it would be able to reach neighboring star [[Alpha Centauri]] in 100 years (approx. velocity of 13,411 km/s, at a distance of 4.5 light years, equivalent to 4.5% of light speed).\n\n {{Main|Antimatter-catalyzed nuclear pulse propulsion}}\n\nIn the mid-1990s, research at [[Pennsylvania State University]] led to the concept of using [[antimatter]] to catalyze nuclear reactions. [[Antiproton]]s would react inside the nucleus of [[uranium]], releasing energy that breaks the nucleus apart as in conventional nuclear reactions. Even a small number of such reactions can start the [[chain reaction]] that would otherwise require a much larger volume of fuel to sustain. Whereas the "normal" [[Critical mass (nuclear)|critical mass]] for [[plutonium]] is about 11.8 kilograms (for a sphere at standard density), with antimatter catalyzed reactions this could be well under one gram.\n\nSeveral rocket designs using this reaction were proposed, some which would use all-fission reactions for interplanetary missions, and others using fission-fusion (effectively a very small version of Orion's bombs) for interstellar missions.\n\n {{infobox rocket engine\n |name            = MSNW magneto-inertial fusion driven rocket\n |image           = The Fusion Driven Rocket powered spacecraft.jpg\n |image_size      = 300px\n |caption         = Concept graphic of a fusion-driven rocket powered spacecraft arriving at Mars\n |country_of_origin=\n |date            =\n |first_date      =\n |last_date       =\n |designer        = MSNW LLC\n |manufacturer    =\n |purpose         = Interplanetary\n |associated      =\n |predecessor     =\n |successor       =\n |status          = Theoretical\n\n |specific_impulse= 1,606 s to 5,722 s (depending on fusion gain)\n |burn_time       = 1 day to 90 days (10 days optimal with gain of 40)\n\n | references = <ref name="sloughetal">{{cite web |first1=John |last1=Slough |first2=Anthony |last2=Pancotti |first3=David |last3=Kirtley |first4=Christopher |last4=Pihl |first5=Michael |last5=Pfaff |url=https://www.nasa.gov/pdf/716077main_Slough_2011_PhI_Fusion_Rocket.pdf |title=Nuclear Propulsion through Direct Conversion of Fusion Energy: The Fusion Driven Rocket |publisher=NASA |date=September 30, 2012 |pages=1\u201331}}</ref>\n |notes           = {{plainlist|\n*'''Fuel''':           Deuterium-tritium cryogenic pellet\n*'''Propellant''': Lithium or aluminum\n*'''Power requirements''': 100 kW to 1,000 kW}}\n}}\nNASA funded MSNW LLC and the [[University of Washington]] in 2011 to study and develop a [[fusion rocket]] through the NASA Innovative Advanced Concepts [[NASA Innovative Advanced Concepts|NIAC]] Program.<ref>{{Cite web|url=http://www.nasa.gov/directorates/spacetech/niac/2011_nuclear_propulsion|title=Nuclear Propulsion Through Direct Conversion of Fusion Energy|first=Loura|last=Hall|date=July 13, 2017|website=NASA}}</ref>\n\nThe rocket uses a form of [[magneto-inertial fusion]] to produce a direct thrust fusion rocket. Magnetic fields cause large metal rings to collapse around the [[deuterium]]-[[tritium]] plasma, triggering fusion. The energy heats and ionizes the shell of metal formed by the crushed rings. The hot, ionized metal is shot out of a magnetic rocket nozzle at a high speed (up to 30 km/s). Repeating this process roughly every minute would propel the spacecraft.<ref>{{cite conference|title=Nuclear Propulsion based on Inductively Driven Liner Compression of Fusion Plasmoids |last1= Slough |first1=J.|last2= Kirtley |first2=D. |conference=AIAA Aerospace Sciences Conference |year=2011|url=http://msnwllc.com/Papers/FDR_AIAA_2011.pdf}}</ref> The fusion reaction is not self-sustaining and requires electrical energy to explode each pulse. With electrical requirements estimated to be between 100 kW to 1,000 kW (300 kW average), designs incorporate solar panels to produce the required energy.<ref name="sloughetal"/> \n \nFoil Liner Compression creates fusion at the proper energy scale. The proof of concept experiment in Redmond, Washington, was to use aluminum liners for compression. However, the ultimate design was to use lithium liners.<ref>{{cite conference|title=Mission Design Architecture for the Fusion Driven Rocket |last1= Pancotti |first1=A. |last2=Slough|first2= J. |last3=Kirtley|first3= D. |conference=AIAA Joint Propulsion Conference|year=2012 |url=http://msnwllc.com/Papers/FDR_JPC_2012.pdf}}</ref><ref>{{cite news |url=http://www.nbcnews.com/science/scientists-develop-fusion-rocket-technology-lab-aim-mars-1B9235633 |title=Scientists develop fusion rocket technology in lab \u2013 and aim for Mars |work=NBC News |date=April 5, 2013 |first=Alan |last=Boyle}}</ref>\n\nPerformance characteristics are dependent on the [[fusion gain|fusion energy gain factor]] achieved by the reactor. Gains were expected to be between 20 and 200, with an estimated average of 40. Higher gains produce higher exhaust velocity, higher specific impulse and lower electrical power requirements. The table below summarizes different performance characteristics for a theoretical 90-day Mars transfer at gains of 20, 40 and 200.\n\n{| class="wikitable"\n|+ | FDR parameters for 90 Mars transfer burn<ref name="sloughetal" />\n|-\n! Total gain !! Gain of 20 !! Gain of 40 !! Gain of 200\n|-\n| Liner mass (kg) || 0.365 || 0.365 || 0.365\n|-\n| Specific impulse (s) || 1,606 || 2,435 || 5,722\n|-\n| Mass fraction || 0.33 || 0.47 || 0.68\n|-\n| Specific mass (kg/kW) || 0.8 || 0.53 || 0.23\n|-\n| Mass propellant (kg) || 110,000 || 59,000 || 20,000\n|-\n| Mass initial (kg) || 184,000 || 130,000 || 90,000\n|-\n| Electrical power required (kW) || 1,019 || 546 || 188\n|}\n\nBy April 2013, MSNW had demonstrated subcomponents of the systems: heating [[deuterium]] [[plasma (physics)|plasma]] up to fusion temperatures and concentrating the magnetic fields needed to create fusion. They planned to put the two technologies together for a test before the end of 2013.<ref name="sloughetal"/><ref name=ps20130408>{{cite news |last=Diep|first=Francie |title=Fusion Rocket Would Shoot People To Mars In 30 Days |url=http://www.popsci.com/science/article/2013-04/fusion-rocket-idea-would-shoot-people-mars |access-date=2013-04-12 |work=Popular Science |date=2013-04-08 }}</ref><ref>{{cite conference|title=The Fusion Driven Rocket |last1=Slough |first1=J. |last2=Pancotti |first2=A. |last3=Kirtley |first3=D. |last4=Pfaff |first4=M. |last5=Pihl |first5=C. |last6=Votroube |first6=G. |conference=NASA NIAC( Phase II) Symposium |date=November 2012|url=http://www.msnwllc.com/Papers/NIAC_PhaseII_FDR.pdf}}</ref>\n\n Pulsed Fission-Fusion (PuFF) propulsion is reliant on principles similar to magneto-inertial fusion, It aims to solve the problem of the extreme stress induced on containment by an Orion-like motor by ejecting the plasma obtained from small fuel pellets that undergo autocatalytic fission and fusion reactions initiated by a [[Z-pinch]]. It is a theoretical propulsion system researched through the NIAC Program by the [[University of Alabama in Huntsville]].<ref>{{Cite web|last=Adams|first=Robert, B.|date=2013|title=Pulsed Fission-Fusion (PuFF) \u2013 Phase I Report|url=https://www.nasa.gov/sites/default/files/files/Adams_2013_PhI_PuFF_inProgress.pdf|url-status=live|archive-url=|archive-date=|access-date=7 February 2021|website=Nasa.gov}}</ref> It is in essence a fusion rocket that uses a Z-pinch configuration, but coupled with a fission reaction to boost the fusion process. \n\nA PuFF fuel pellet, around 1 cm in diameter,<ref>{{Cite web|last=Adams|first=Robert, B.|date=|title=The Pulsed Fission-Fusion (PuFF) Concept for Deep Space Exploration and Terrestrial Power Generation|url=https://www.nasa.gov/sites/default/files/atoms/files/the_pulsed_fission_-_fusion_puff_concept_for_deep_space_exploration_and_terrestrial_power.pdf|url-status=live|archive-url=|archive-date=|access-date=|website=Nasa.gov}}</ref> consists of two components: A deuterium-tritium (D-T) cylinder of plasma, called the ''target'', which undergoes fusion, and a surrounding [[U-235]] sheath that undergoes fission enveloped by a lithium liner. Liquid lithium, serving as a moderator, fills the space between the D-T cylinder and the uranium sheath.  Current is run through the liquid lithium, a [[Lorentz force]] is generated which then compresses the D-T plasma by a factor of 10 in what is known as a Z-pinch. The compressed plasma reaches criticality and undergoes fusion reactions. However, the fusion energy gain (''Q'') of these reactions is far below breakeven (''Q'' < 1), meaning that the reaction consumes more energy than it produces. \n\nIn a PuFF design, the fast neutrons released by the initial fusion reaction induce fission in the U-235 sheath. The resultant heat causes the sheath to expand, increasing its implosion velocity onto the D-T core and compressing it further, releasing more fast neutrons. Those again amplify the fission rate in the sheath, rendering the process autocatalytic. It is hoped that this results in a complete burn up of both the fission and fusion fuels, making PuFF more efficient than other nuclear pulse concepts.<ref>{{Cite journal|last=Winterberg|first=Friedwart|date=2000|title=Autocatalytic fission\u2013fusion microexplosions for nuclear pulse propulsion |url=|journal=Acta Astronautica|volume=47|issue=12|pages=879\u2013883|doi=10.1016/S0094-5765(00)00136-3|bibcode=2000AcAau..47..879W|via=Elsevier Science Direct}}</ref><ref>{{Cite journal|last=Adams|first=Robert, B.|date=2014|title=Developing the Pulsed Fission-Fusion (PuFF) Engine|url=|journal=Propulsion and Energy Forum|volume=|pages=|via=}}</ref> Much like in a magneto-inertial fusion rocket, the performance of the engine is dependent on the degree to which the fusion gain of the D-T target is increased.\n\nOne "pulse" consist of the injection of a fuel pellet into the combustion chamber, its consumption through a series of fission-fusion reactions, and finally the ejection of the released plasma through a magnetic nozzle, thus generating thrust. A single pulse is expected to take only a fraction of a second to complete."}},
{"article_title": "Non-linear editing", "pageid": "70729", "revid": "1062302050", "timestamp": "2021-12-27T16:44:54Z", "history_paths": [["Non-linear editing --- Introduction ---", "History"]], "categories": ["film and video technology", "film editing", "digital audio", "video editing software", "filmmaking"], "heading_tree": {"Non-linear editing --- Introduction ---": {"Basic techniques": {}, "Broadcast workflows and advantages": {}, "Accessing the material": {}, "Editor brands": {}, "Home use": {}, "History": {"First non-linear editor": {}, "The 1980s": {}, "The 1990s": {}, "DV": {}, "HD": {}, "The cloud": {}, "4K": {}, "8K": {}, "Image editing": {}}, "Quality": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Non-linear editing --- Introduction ---|History": "{{cleanup rewrite|section|date=May 2012}}\n\nWhen [[videotape]]s were first developed in the 1950s, the only way to edit was to physically cut the tape with a razor blade and splice segments together.  While the footage excised in this process was not technically destroyed, continuity was lost and the footage was generally discarded. In 1963, with the introduction of the [[Ampex]] Editec, video tape could be edited electronically with a process known as [[linear video editing]] by selectively copying the original footage to another tape called a ''master''.  The original recordings are not destroyed or altered in this process. However, since the final product is a copy of the original, there is a generation loss of quality.\n\n The first truly non-linear editor, the [[CMX 600]], was introduced in 1971 by [[CMX Systems]], a joint venture between [[CBS]] and [[Memorex]].<ref>{{citation |archive-url=https://web.archive.org/web/20130410092334/http://sundialmedia.com/sait/articles/found_a/heat_f.htm |archive-date=2013-04-10 |url=http://sundialmedia.com/sait/articles/found_a/heat_f.htm |title=The History of Digital Nonlinear Editing |work=Facer Ezine}}</ref><ref>{{citation |archive-url=https://web.archive.org/web/20071021231834/http://nonlinear.info/N4.history.pdf |archive-date=2007-10-21 |url=http://nonlinear.info/N4.history.pdf |title=A Brief History Of Electronic Editing |work=Non Linear}}</ref>  It recorded and played back black-and-white analog video recorded in "[[skip-field]]" mode on modified [[disk pack]] drives the size of washing machines.  These were commonly used to store about half an hour of data digitally on mainframe computers of the time.  The 600 had a console with two monitors built in.  The right monitor, which played the preview video, was used by the editor to make cuts and edit decisions using a [[light pen]].  The editor selected from options superimposed as text over the preview video. The left monitor was used to display the edited video.  A DEC [[PDP-11]] computer served as a controller for the whole system.  Because the video edited on the 600 was in low-resolution black and white, the 600 was suitable only for offline editing.\n\n Non-linear editing systems were built in the 1980s using computers coordinating multiple [[LaserDisc]]s or banks of VCRs.  One example of these tape and disc-based systems was Lucasfilm's [[EditDroid]], which used several LaserDiscs of the same raw footage to simulate random-access editing.{{efn|A compatible system called [[SoundDroid]] was developed for sound post-production. This is considered to be one of the earliest [[digital audio workstation]]s.{{citation needed|date=May 2019|reason=Not mentioned at [[digital audio workstation]].}}}} EditDroid was demonstrated at NAB in 1984.<ref name="fraser-harrison">{{cite web |title=What was EditDroid? |url=https://fraser-harrison-postproduction.blogspot.com/2013/03/what-was-editdroid.html |author=Fraser Harrison |date=2013-03-14 |access-date=2019-08-29}}<!--ref indicates 1994 NAB #62. this appears to be a typo. first [[NAB Show was]] 1923 so #62 was in 1984.--></ref> EditDroid was the first system to introduce modern concepts in non-linear editing such as timeline editing and clip bins.\n\nThe LA-based post house Laser Edit{{efn|Laser Edit later merged with Pacific Video as Laser-Pacific.}} also had an in-house system using recordable random-access LaserDiscs.\n\nThe most popular non-linear system in the 1980s was [[Ediflex]],<ref>{{cite web |url=http://www.articles.adsoft.org/postproduction.htm |archive-url=https://web.archive.org/web/20120302111642/http://www.articles.adsoft.org/postproduction.htm |archive-date=2012-03-02 |author=Richard Seel |title=Developments in Post Production 1946 - 1991}}</ref> which used a bank of Sony JVC VCRs for offline editing. Ediflex was introduced in 1983 on the Universal series "[[Still the Beaver]]". By 1985 it was used on over 80% of filmed network programs. In 1985 Ediflex maker, Cinedco was awarded the [[Technical Emmy]] for "Design and Implementation of Non-Linear Editing for Filmed Programs."<ref>{{cite book|first1=John|last1=Buck|title=Timeline, A History of Editing |publisher=Enriched Books |location=Melbourne|year=1988 | pages = 448 |isbn=978-0-646-49224-7}}</ref><ref>{{cite news\n |title       = NBC LEADS EMMY WINNERS WITH 15 HONORS IN BEHIND-SCENES CATEGORIES\n |newspaper   = Associated Press\n |location    = Padadena, CA\n |url         = http://www.apnewsarchive.com/1986/NBC-Leads-Emmy-Winners-With-15-Honors-In-Behind-Scenes-Categories/id-b0bef37b4cc86b35ea770cb2443d3dc4\n |date        = September 8, 1986\n |access-date  = July 30, 2013\n |archive-url  = https://web.archive.org/web/20150928230637/http://www.apnewsarchive.com/1986/NBC-Leads-Emmy-Winners-With-15-Honors-In-Behind-Scenes-Categories/id-b0bef37b4cc86b35ea770cb2443d3dc4\n |archive-date = September 28, 2015\n |url-status     = live\n}}</ref>\n\nIn 1984, [[Montage Picture Processor]] was demonstrated at NAB.<ref name="fraser-harrison"/> Montage used 17 identical copies of a set of film rushes on modified consumer Betamax VCRs.  A custom circuit board was added to each deck that enabled frame-accurate switching and playback using vertical interval timecode. Intelligent positioning and sequencing of the source decks provided a simulation of random-access playback of a lengthy edited sequence without any rerecording. The theory was that with so many copies of the rushes, there could always be one machine cued up to replay the next shot in real time. Changing the EDL could be done easily, and the results seen immediately.\n\nThe first feature edited on the Montage was Sidney Lumet's ''[[Power (1986 film)|Power]]''.  Notably, Francis Coppola edited ''[[The Godfather Part III]]'' on the system, and Stanley Kubrick used it for ''[[Full Metal Jacket]]''.  It was used on several episodic TV shows (''[[Knots Landing]]'', for one) and on hundreds of commercials and music videos.\n\nThe original Montage system won an Academy Award for Technical Achievement in 1988.{{citation needed|reason=Doesn't appear in list at [[Academy Scientific and Technical Award]]|date=September 2019}} Montage was reincarnated as Montage II in 1987, and Montage III appeared at NAB in 1991, using digital disk technology, which should prove to be considerably less cumbersome than the Betamax system.\n\nAll of these original systems were slow, cumbersome, and had problems with the limited computer horsepower of the time, but the mid-to-late-1980s saw a trend towards non-linear editing, moving away from film editing on [[Moviola]]s and the linear videotape method using [[U-matic]] VCRs. Computer processing advanced sufficiently by the end of the '80s to enable true digital imagery, and has progressed today to provide this capability in personal desktop computers.\n\nAn example of computing power progressing to make non-linear editing possible was demonstrated in the first all-digital non-linear editing system, the "Harry" effects compositing system manufactured by [[Quantel]] in 1985.  Although it was more of a video effects system, it had some non-linear editing capabilities. Most importantly, it could record (and apply effects to) 80 seconds (due to hard disk space limitations) of broadcast-quality uncompressed digital video encoded in 8-bit [[CCIR 601]] format on its built-in hard disk array.\n\n The term ''nonlinear editing'' was formalized in 1991 with the publication of Michael Rubin's ''Nonlinear: A Guide to Digital Film and Video Editing'' (Triad, 1991)\u2014which popularized this terminology over other terminology common at the time, including ''real-time'' editing, ''random-access'' or ''RA'' editing, ''virtual'' editing, ''electronic film'' editing, and so on.{{Citation needed|date=December 2016}}\n\nNon-linear editing with computers as it is known today was first introduced by [[Editing Machines Corp.]] in 1989 with the EMC2 editor, a PC-based non-linear off-line editing system that utilized magneto-optical disks for storage and playback of video, using half-screen-resolution video at 15 frames per second. A couple of weeks later that same year, [[Avid Technology|Avid]] introduced the Avid/1, the first in the line of their [[Media Composer]] systems. It was based on the [[Apple Macintosh]] computer platform ([[Macintosh II]] systems were used) with special hardware and software developed and installed by Avid.\n\nThe video quality of the Avid/1 (and later [[Media Composer]] systems from the late 1980s) was somewhat low (about VHS quality), due to the use of a very early version of a [[Motion JPEG]] (M-JPEG) [[codec]].  It was sufficient, however, to provide a versatile system for offline editing.  ''[[Lost in Yonkers (film)|Lost in Yonkers]]'' (1993) was the first film edited with Avid Media Composer, and the first long-form documentary so edited was the HBO program ''Earth and the American Dream'', which won a National Primetime Emmy Award for Editing in 1993.\n\nThe NewTek [[Video Toaster Flyer]] for the [[Amiga]] included non-linear editing capabilities in addition to processing live video signals.  The Flyer used [[hard drive]]s to store video clips and audio, and supported complex scripted playback. The Flyer provided simultaneous dual-channel playback, which let the Toaster's [[video switcher]] perform transitions and other effects on [[video clip]]s without additional [[Rendering (computer graphics)|rendering]].  The Flyer portion of the Video Toaster/Flyer combination was a complete computer of its own, having its own [[microprocessor]] and [[embedded software]]. Its hardware included three embedded [[SCSI]] controllers. Two of these SCSI buses were used to store video data, and the third to store audio.  The Flyer used a proprietary [[wavelet compression]] algorithm known as VTASC, which was well regarded at the time for offering better visual quality than comparable non-linear editing systems using [[motion JPEG]].\n\nUntil 1993, the Avid Media Composer was most often used for editing commercials or other small-content and high-value projects. This was primarily because the purchase cost of the system was very high, especially in comparison to the offline tape-based systems that were then in general use. Hard disk storage was also expensive enough to be a limiting factor on the quality of footage that most editors could work with or the amount of material that could be held digitized at any one time.{{efn|In editing facilities rented by the hour or the day, a production's digitized rushes would usually be deleted at the end of the hire, so that the full amount of hard disk storage was available to the next client.}}\n\nUp until 1992, the Apple Macintosh computers could access only 50 [[gigabytes]] of storage at once.  This limitation was overcome by a digital video R&D team at the [[Disney Channel]] led by [[Rick Eye]]. By February 1993, this team had integrated a long-form system that let the Avid Media Composer running on the Apple Macintosh access over seven [[terabytes]] of digital video data. With instant access to the shot footage of an entire [[movie]], long-form non-linear editing was now possible. The system made its debut at the [[National Association of Broadcasters|NAB]] conference in 1993 in the booths of the three primary sub-system manufacturers, Avid, [[Silicon Graphics]] and [[Sony]].  Within a year, thousands of these systems had replaced [[35mm movie film|35mm film]] editing equipment in major motion picture studios and TV stations worldwide.<ref>{{cite book|url=https://books.google.com/books?id=k9KkIsSb5x0C&q=media+100+editing+suite+history&pg=PA137 |title=Producing Video Podcasts: A Guide for Media Professionals |first1=Richard |last1=Harrington |first2=Mark |last2=Weiser |first3=RHED |last3=Pixel |date=12 February 2019 |publisher=Taylor & Francis |isbn=9780240810294 |via=Google Books}}</ref>\n\nAlthough M-JPEG became the standard codec for NLE during the early 1990s, it had drawbacks. Its high computational requirements ruled out software implementations imposing extra cost and complexity of hardware compression/playback cards. More importantly, the traditional tape [[workflow]] had involved editing from videotape, often in a rented facility. When the editor left the edit suite, they could securely take their tapes with them. But the M-JPEG data rate was too high for systems like Avid/1 on the [[Apple Macintosh|Mac]] and [[Lightworks]] on PC to store the video on removable storage. The content needed to be stored on fixed hard disks instead. The secure tape paradigm of keeping your content with you was not possible with these fixed disks. Editing machines were often rented from facilities houses on a per-hour basis, and some productions chose to delete their material after each edit session, and then ingest it again the next day to guarantee the security of their content.{{Citation needed|date=November 2009}} In addition, each NLE system had storage limited by its fixed disk capacity.\n\nThese issues were addressed by a small UK company, [[Eidos Interactive]]. Eidos chose the new [[ARM architecture|ARM]]-based computers from the UK and implemented an editing system, launched in Europe in 1990 at the [[International Broadcasting Convention]]. Because it implemented its own compression software designed specifically for non-linear editing, the Eidos system had no requirement for JPEG hardware and was cheap to produce. The software could decode multiple video and audio streams at once for real-time effects at no extra cost. But most significantly, for the first time, it supported unlimited cheap removable storage. The Eidos Edit 1, Edit 2, and later Optima systems let the editor use ''any'' Eidos system, rather than being tied down to a particular one, and still keep his data secure. The Optima software editing system was closely tied to [[Acorn Computers Ltd|Acorn]] hardware, so when Acorn stopped manufacturing the [[Risc PC]] in the late 1990s, Eidos discontinued the Optima system.{{citation needed|reason=Entire paragraph is unsourced and there is nothing helpful in [[Eidos Interactive]].|date=October 2020}}\n\nIn the early 1990s, a small American company called Data Translation took what it knew about coding and decoding pictures for the US military and large corporate clients and spent $12 million developing a desktop editor based on its proprietary compression algorithms and off-the-shelf parts. Their aim was to democratize the desktop and take some of Avid's market. In August 1993, [[Media 100]] entered the market, providing would-be editors with a low-cost, high-quality platform.{{citation needed|reason=Entire paragraph is unsourced and there are no helpful sources in [[Media 100]].|date=October 2020}}\n\nAround the same period, two other competitors provided non-linear systems that required special hardware\u2014typically cards added to the computer system. Fast Video Machine was a PC-based system that first came out as an offline system, and later became more [[online editing]] capable. The [[Imix video cube]] was also a contender for media production companies. The Imix Video Cube had a control surface with faders to allow mixing and shuttle control. Data Translation's Media 100 came with three different JPEG codecs for different types of graphics and many resolutions. These other companies caused tremendous downward market pressure on Avid. Avid was forced to continually offer lower-priced systems to compete with the Media 100 and other systems.\n\nInspired by the success of Media 100, members of the [[Adobe Premiere Pro|Premiere]] development team left Adobe to start a project called "Keygrip" for Macromedia.  Difficulty raising support and money for development led the team to take their non-linear editor to the [[NAB Show]]. After various companies made offers, Keygrip was purchased by Apple as Steve Jobs wanted a product to compete with Adobe Premiere in the desktop video market. At around the same time, Avid\u2014now with Windows versions of its editing software\u2014was considering abandoning the Macintosh platform. Apple released [[Final Cut Pro]] in 1999, and despite not being taken seriously at first by professionals, it has evolved into a serious competitor to entry level's Avid's systems.\n\n Another leap came in the late 1990s with the launch of [[DV|DV-based]] video formats for consumer and professional use. With DV came [[IEEE 1394]] (FireWire/iLink), a simple and inexpensive way of getting video into and out of computers. Users no longer had to convert video from [[analog signal|analog]] to digital\u2014it was recorded as digital to start with\u2014and FireWire offered a straightforward way to transfer video data without additional hardware. With this innovation, editing became a more realistic proposition for software running on standard computers. It enabled desktop editing producing high-quality results at a fraction of the cost of earlier systems.\n\n In early 2000, the introduction of highly compressed HD formats such as [[HDV]] has continued this trend, making it possible to edit HD material on a standard computer running a software-only editing system.\n\n[[Avid Technology|Avid]] is an industry standard used for major feature films, television programs, and commercials.<ref name="Nonlinear-editors">{{cite magazine|date=September 1, 2011|title=Nonlinear editors|url=http://www.tvtechnology.com/multiformat/0112/nonlinear-editors/242232|archive-url=https://web.archive.org/web/20180104191436/http://www.tvtechnology.com/multiformat/0112/nonlinear-editors/242232|archive-date=2018-01-04|magazine=Broadcast engineering}}</ref> Final Cut Pro received a [[Technology & Engineering Emmy Award#2001 Awards|Technology & Engineering Emmy Award]] in 2002.\n\nSince 2000, many personal computers include basic non-linear video editing software free of charge. This is the case of Apple [[iMovie]] for the Macintosh platform, various open-source programs like [[Kdenlive]], [[Cinelerra-GG Infinity]] and [[PiTiVi]] for the Linux platform, and [[Windows Movie Maker]] for the Windows platform. This phenomenon has brought low-cost non-linear editing to consumers.\n\n The demands of video editing in terms of the volumes of data involved means the proximity of the stored footage being edited to the NLE system doing the editing is governed partly by the capacity of the data connection between the two. The increasing availability of broadband internet combined with the use of lower-resolution copies of original material provides an opportunity to not just review and edit material remotely but also open up access to far more people to the same content at the same time. In 2004 the first [[cloud-based video editor]], known as [[Blackbird (software)|Blackbird]] and based on technology invented by [[Stephen B. Streater|Stephen Streater]], was demonstrated at [[International Broadcasting Convention|IBC]] and recognised by the [[Royal Television Society|RTS]] the following year. Since that time a number of other cloud-based editors have become available including systems from [[Avid Technology|Avid]], [[WeVideo]] and [[Grabyo]]. Despite their reliance on a network connection, the need to ingest material before editing can take place, and the use of lower-resolution ''video proxies'', their adoption has grown. Their popularity has been driven largely by efficiencies arising from opportunities for greater collaboration and the potential for cost savings derived from using a shared platform, hiring rather than buying infrastructure, and the use of conventional IT equipment over hardware specifically designed for video editing.\n\n {{As of|2014}}, [[4K resolution|4K Video]] in NLE was fairly new, but it was being used in the creation of many movies throughout the world, due to the increased use of advanced 4K cameras such as the [[Red Digital Cinema Camera Company|Red Camera]]. Examples of software for this task include [[Avid Technology|Avid]] [[Media Composer]], [[Apple Inc.|Apple's]] [[Final Cut Pro X]], [[Sony Vegas]], [[Adobe Premiere]], [[DaVinci Resolve]], [[Edius]], and [[Cinelerra-GG Infinity]] for Linux.{{citation needed|date=August 2021}}\n\n {{asof|2019}} [[8K resolution|8K video]] was relatively new. 8K video editing requires advanced hardware and software capable of handling the standard.{{citation needed|date=August 2021}}\n\n For imaging software, early works such as [[Kai Krause|HSC Software]]'s Live Picture<ref>{{Cite web |url=http://www.pixiq.com/article/live-picture |title=Archived copy |access-date=2016-07-01 |archive-url=https://web.archive.org/web/20130202102219/http://www.pixiq.com/article/live-picture |archive-date=2013-02-02 |url-status=dead }}</ref> brought non-destructive editing to the professional market and current efforts such as [[GEGL]] provide an implementation being used in open-source image editing software."}},
{"article_title": "Tape recorder", "pageid": "70912", "revid": "1061163912", "timestamp": "2021-12-20T01:32:59Z", "history_paths": [["Tape recorder --- Introduction ---", "History"]], "categories": ["audio storage", "sound production technology", "sound recording", "sound recording technology", "articles containing video clips", "tape recording", "audiovisual introductions in 1886"], "heading_tree": {"Tape recorder --- Introduction ---": {"History": {"Wax strip recorder": {}, "Celluloid strip recorder": {}, "Photoelectric paper tape recorder": {}, "Magnetic recording": {}, "Wire recorders": {}, "Early steel tape recorders": {}, "Modern tape recorders": {}}, "Commercialization": {"American developments": {}, "Tape recording at the BBC": {}, "Standardized products": {}}, "Later developments": {}, "Operation": {"Electrical": {}, "Mechanical": {}}, "Limitations": {}, "Tape recorder variety": {}, "Uses": {}, "Tape speeds": {}, "Tape formats": {}, "Recorders": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Tape recorder --- Introduction ---|History": "{{further|Timeline of audio formats}}\n{{gallery |title=Early tape recorders |width=250\n|File:Early experimental non-magnetic Tape Recorder invented by the Volta Associates -Bell & Tainter -i013.jpg |An early experimental '''non-magnetic tape recorder''' patented in 1886 by Alexander Graham Bell's Volta Laboratory.\n|File:Tape Recorder 1909.tif |1909 analog tape recorder of Franklin C. Goodale. This machine had 15 Tracks\n|File:Tape Recorder 1909.pdf |Franklin C. Goodale built the first working tape recorder in 1909 and got the patent for this invention\n|File:Prototype of the Goodale Tape Recorder.jpg |Prototype of the Goodale tape recorder. The patent is based on this machine.\n}}\n\n The earliest known audio tape recorder was a [[Magnetism|non-magnetic]], [[electricity|non-electric]] version invented by [[Alexander Graham Bell]]'s [[Volta Laboratory and Bureau|Volta Laboratory]] and patented in 1886 ({{US patent|341214}}). It employed a {{convert|3/16|in|mm|adj=mid|-wide}} strip of wax-covered paper that was coated by dipping it in a solution of [[beeswax]] and [[Paraffin wax|paraffin]] and then had one side scraped clean, with the other side allowed to harden. The machine was of sturdy wood and metal construction, and hand-powered by means of a knob fastened to the [[flywheel]]. The wax strip passed from one eight-inch reel around the periphery of a pulley (with guide flanges) mounted above the V-pulleys on the main vertical shaft, where it came in contact with either its recording or playback [[stylus]]. The tape was then taken up on the other reel. The sharp recording stylus, actuated by a vibrating mica diaphragm, cut the wax from the strip. In playback mode, a dull, loosely mounted stylus, attached to a rubber diaphragm, carried the reproduced sounds through an ear tube to its listener. Both recording and playback styluses, mounted alternately on the same two posts, could be adjusted vertically so that several recordings could be cut on the same {{convert|3/16|in|mm|adj=mid|-wide}} strip.<ref name="Newville" />\n\nWhile the machine was never developed commercially, it somewhat resembled the modern magnetic tape recorder in its design. The tapes and machine created by Bell's associates, examined at one of the [[Smithsonian Institution]]'s museums, became brittle, and the heavy paper reels warped. The machine's playback head was also missing. Otherwise, with some reconditioning, they could be placed into working condition.<ref name="Newville">Newville, Leslie J. [http://www.gutenberg.org/files/30112/30112-h/30112-h.htm Development of the Phonograph at Alexander Graham Bell's Volta Laboratory], United States National Museum Bulletin, [[Smithsonian Institution|United States National Museum]] and the [[Museum of History and Technology]], Washington, D.C., 1959, No. 218, Paper 5, pp.69\u201379. Retrieved from ProjectGutenberg.org.</ref>\n\nThe waxed tape recording medium was inferior to Edison's [[Phonograph cylinder|wax cylinder]] medium, and Edison's wax cylinder phonograph became the first widespread sound recording technology, used for both entertainment and office dictation.\n\n [[File:Franklin C. Goodale Tape Recorder D.jpg|thumb|This tape recorder of Dr. Goodale is exhibited in the private Phonograph Museum in Mariazell, Austria.]]\nFranklin C. Goodale adapted movie film for analog audio recording. He received the patent for his invention in 1909.<ref>{{cite patent\n| country       = United States\n| number        = 944608\n| status        = patent\n| title         = Sound-reproducing machine\n| pubdate       = \n| gdate         = 28 December 1909\n| fdate         = 26 June 1908\n| pridate       = \n| inventor      = \n| invent1       = F. G. Goodale\n| invent2       = \n| assign1       = \n| assign2       = \n| class = \n| url = https://patents.google.com/patent/US944608\n}}</ref> The celluloid film was inscribed and played back with a stylus, in a manner similar to the wax cylinders of Edison's gramophone. The patent description states that the machine could store six records on the same strip of film, side by side, and it was possible to switch between them. In 1912, a similar process was used for the Hiller [[talking clock]].\n\n In 1932, after six years of developmental work, including a patent application in 1931,<ref>USPTO. [https://books.google.com/books?ei=uKJ2TOTzM6eCnAek7aCdCw&ct=result&id=gCegAAAAMAAJ Official Gazette Of The United States Patent Office], United States Patent Office, 1936, Volume 463, pp.537.</ref><ref>USPTO. [http://www.google.com/patents/US2030973 United States Patent Office, Patent US2030973 A, "Method of and apparatus for electrically recording and reproducing sound or other vibrations"]</ref> Merle Duston, a [[Detroit]] radio engineer, created a tape recorder capable of recording both sounds and voice that used a low-cost chemically treated paper tape.  During the recording process, the tape moved through a pair of electrodes which immediately imprinted the modulated sound signals as visible black stripes into the paper tape's surface.  The [[sound track]] could be immediately replayed from the same recorder unit, which also contained photoelectric sensors, somewhat similar to the various [[sound-on-film]] technologies of the era.<ref>Popular Science. [https://books.google.com/books?id=2CcDAAAAMBAJ&pg=PA40&lpg=PA40#v=onepage&q&f=false Record Of Voice Now Made On Moving Paper Tape], Popular Science, Bonnier Corporation, February 1934, pp.40, Vol. 124, No. 2, ISSN 0161-7370.</ref><ref name="Onosko">Onosko, Tim. [https://books.google.com/books?id=2XKQAAAACAAJ Wasn't The Future Wonderful?: A View Of Trends And Technology From The 1930s: (article) Book Reads Itself Aloud: After 500 Years, Books Are Given Voice], Dutton, 1979, pp.73, {{ISBN|0-525-47551-6}}, {{ISBN|978-0-525-47551-4}}. Article attributed to: [[Popular Mechanics]], date of publication unstated, likely c. February 1934.</ref>\n\n [[Magnetic recording]] was conceived as early as 1878 by the American engineer [[Oberlin Smith]]<ref>Engel, Friedrich Karl, ed. (2006) "Oberlin Smith and the invention of magnetic sound recording:  An appreciation on the 150th anniversary of the inventor's birth".  Smith's caveat of 4 October 1878 regarding the recording of sound on magnetic media appears on pp. 14\u201316.  Available at:  [http://www.richardhess.com/tape/history/Engel--Oberlin_Smith_2006.pdf RichardHess.com]</ref><ref>Smith, Oberlin (1888 September 8) [https://books.google.com/books?id=zYVMAAAAYAAJ&pg=RA3-PA116#v=onepage&q&f=false "Some possible forms of phonograph,"] ''The Electrical World'', '''12''' (10) :  116\u2013117.</ref> and demonstrated in practice in 1898 by Danish engineer [[Valdemar Poulsen]].<ref>Poulsen, Valdemar, [http://pdfpiw.uspto.gov/.piw?Docid=00661619&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect2%3DPTO1%2526Sect2%3DHITOFF%2526p%3D1%2526u%3D%2Fnetahtml%2FPTO%2Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526d%3DPALL%2526S1%3D0661619.PN.%2526OS%3DPN%2F661619%2526RS%3DPN%2F661619&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page "Method of recording and reproducing sounds or signals,"] U.S. Patent no. 661,619 (filed:  1899 July 8 ; issued: 1900 November 13).</ref><ref name="Nagra">{{cite web |title=Magnetic Recording Timeline |archive-url=https://webarchive.nla.gov.au/awa/20040302130000/http://pandora.nla.gov.au/pan/13071/20040303-0000/www.acmi.net.au/AIC/HIST_REC_NAGRA.html |archive-date=2004-03-02 |url=http://www.acmi.net.au/AIC/HIST_REC_NAGRA.html |author=Nagra Company}}{{cbignore|bot=medic}}</ref> Analog magnetic [[wire recording]], and its successor, [[magnetic tape]] recording, involve the use of a magnetizable medium which moves with a constant speed past a recording head. An electrical signal, which is analogous to the sound that is to be recorded, is fed to the recording head, inducing a pattern of magnetization similar to the signal. A playback head can then pick up the changes in magnetic field from the tape and convert it into an electrical signal to be [[Amplifier|amplified]] and played back through a [[loudspeaker]].\n\n {{main|Wire recording}}\n[[File:Telegrafon 8154.jpg|thumb|right|Magnetic wire recorder, invented by [[Valdemar Poulsen]], 1898. It is exhibited at [[Brede works]] Industrial Museum, Lyngby, Denmark.]]\n\nThe first wire recorder was the Telegraphone invented by Valdemar Poulsen in the late 1890s.  Wire recorders for law and office dictation and telephone recording were made almost continuously by various companies (mainly the American Telegraphone Company) through the 1920s and 1930s. These devices were mostly sold as consumer technologies after World War II.\n\nWidespread use of wire recording occurred within the decades spanning from 1940 until 1960, following the development of inexpensive designs licensed internationally by the Brush Development Company of Cleveland, Ohio and the Armour Research Foundation of the Armour Institute of Technology (later [[Illinois Institute of Technology]]).{{Citation needed|date=July 2009}} These two organizations licensed dozens of manufacturers in the U.S., Japan, and Europe.{{Citation needed|date=July 2009}}  Wire was also used as a recording medium in [[Flight recorder|black box]] voice recorders for aviation in the 1950s.\n\nConsumer wire recorders were marketed for home entertainment or as an inexpensive substitute for commercial office dictation recorders, but the development of consumer magnetic tape recorders starting in 1946, with the BK 401 Soundmirror, using paper-based tape,<ref name=CLEVE02/><!--less reliable, but interesting refs: http://esrv.net/brush_bk401.html, http://www.radiomuseum.org/r/brush_bk401.html--> gradually drove wire recorders from the market, being "pretty much out of the picture" by 1952.<ref>Mooney, Mark Jr. "The History of Magnetic Recording." Hi-Fi Tape Recording 5:3 (February 1958), 37. This detailed, illustrated 17-page article is a fundamental source for early history of magnetic (wire/tape) recording: https://worldradiohistory.com/Archive-All-Audio/Archive-Tape-Recording/50s/Tape-Recording-1958-02.pdf</ref>\n\n [[File:Blattnerphone recorder 1937.jpg|thumb|Blattnerphone steel tape recorder at BBC studios, London, 1937]]\n\nIn 1924 a German engineer, Kurt Stille, developed the Poulsen wire recorder as a dictating machine.<ref>{{Cite web|title=Magnetic tape recorder - Kurt Stille, Marconi's Wireless Telegraph Company|url=https://artsandculture.google.com/asset/magnetic-tape-recorder-kurt-stille-marconi-s-wireless-telegraph-company/mAFj8zsPfUBqrw|access-date=2020-06-20|website=Google Arts & Culture|language=en}}</ref> The following year a fellow German, [[Louis Blattner]], working in Britain, licensed Stille's device and started work on a machine which would instead record on a magnetic steel tape, which he called the Blattnerphone.<ref>{{citation |url=http://www.orbem.co.uk/tapes/blattner.htm |title=Blattnerphone |access-date=2013-12-11}}</ref> The tape was 6 mm wide and 0.08 mm thick, travelling at 5 feet per second; the recording time was 20 minutes.\n\nThe [[BBC]] installed a Blattnerphone at Avenue House<!--Probably not [[Avenue House]]. [http://www.bbceng.info/Equipment/ed_top.htm This] mentions more than one Avenue House.--> in September 1930 for tests, and used it to record [[George V|King George V]]'s speech at the opening of the [[Round Table Conferences (India)|India Round Table Conference]] on 12 November 1930. Though not considered suitable for music the machine continued in use and was moved to [[Broadcasting House]] in March 1932, a second machine also being installed. In September 1932, a new model was installed, using 3 mm tape with a recording time of 32 minutes.\n\nIn 1933, the [[Marconi Company]] purchased the rights to the Blattnerphone, and newly developed Marconi-Stille recorders were installed in the BBC's [[Maida Vale Studios]] in March 1935.<ref>{{citation |url=http://www.orbem.co.uk/tapes/ms.htm |title=Marconi-Stille recorders |access-date=2013-12-11}}</ref> The quality and reliability was slightly improved, though it still tended to be obvious that one was listening to a recording. A reservoir system containing a loop of tape helped to stabilize the speed. The tape was 3 mm wide and traveled at 1.5  meters/second.<ref name="Nagra"/> By September there were three recording rooms, each with two machines.\n\nThey were not easy to handle. The reels were heavy and expensive and the steel tape has been described as being like a traveling razor blade. The tape was liable to snap, particularly at joints, which at 1.5  meters/second could rapidly cover the floor with loops of the sharp-edged tape. Rewinding was done at twice the speed of the recording.\n\nDespite these drawbacks, the ability to make replayable recordings proved useful, and even with subsequent methods coming into use (direct-cut discs<ref>{{citation |url=http://rfwilmut.net/broadcast/recording4.html |title=Directly-cut discs |access-date=2013-12-11}}</ref> and Philips-Miller optical film<ref>{{citation |url=http://rfwilmut.net/broadcast/recording3.html |title=Optical film |access-date=2013-12-11}}),</ref> the Marconi-Stilles remained in use until the late 1940s.<ref>Information in this section from 'BBC Engineering 1922-1972' by Edward Pawley, pp178-182; plus some from colleagues who worked in BH in the 1930s.</ref>\n{{clear}}\n\n [[File:Ton S.b, tape unit.jpg|thumb|right|Magnetophon from a German radio station in World War II]]\n\nMagnetic tape recording as we know it today was developed in Germany during the 1930s at [[BASF]] (then part of the chemical giant [[IG Farben]]) and [[AEG]] in cooperation with the state radio [[Reichs-Rundfunk-Gesellschaft|RRG]].  This was based on [[Fritz Pfleumer]]'s 1928 invention of paper tape with oxide powder lacquered to it. The first practical tape recorder from [[AEG]] was the [[Magnetophon K1]], demonstrated in Germany in 1935. {{ill|Eduard Sch\u00fcller (engineer)|lt=Eduard Sch\u00fcller|de}} of AEG built the recorders and developed a ring-shaped recording and playback head.  It replaced the needle-shaped head which tended to shred the tape. Friedrich Matthias of IG Farben/BASF developed the recording tape, including the oxide, the binder, and the backing material. Walter Weber, working for {{ill|Hans Joachim von Braunm\u00fchl|de}} at the RRG, discovered the [[AC bias]]ing technique, which radically improved sound quality.<ref name="fenster"/>\n\nDuring [[World War II]], the [[Allies of World War II|Allies]] noticed that certain German officials were making radio broadcasts from multiple time zones almost simultaneously.<ref name="fenster"/> Analysts such as [[Richard H. Ranger]] believed that the broadcasts had to be transcriptions, but their audio quality was indistinguishable from that of a live broadcast<ref name="fenster"/> and their duration was far longer than was possible even with 16 rpm transcription discs.{{efn|The Allies were aware of the existence of the pre-war Magnetophon recorders, but not of the introduction of high-frequency [[Tape bias|bias]] and PVC-backed tape.<ref>Information from ''BBC Engineering 1922\u20131972'' by Edward Pawley, page 387.</ref>}} In the final stages of the war in Europe, the Allied capture of a number of German [[Magnetophon]] recorders from [[Radio Luxembourg (German)|Radio Luxembourg]] aroused great interest. These recorders incorporated all the key technological features of modern analog magnetic recording and were the basis for future developments in the field."}},
{"article_title": "Document management system", "pageid": "71608", "revid": "1061754108", "timestamp": "2021-12-23T19:04:55Z", "history_paths": [["Document management system --- Introduction ---", "History"]], "categories": ["information technology management", "document management systems", "records management technology"], "heading_tree": {"Document management system --- Introduction ---": {"History": {}, "Components": {}, "Standardization": {}, "Document control": {}, "Integrated DM": {}, "Document management software": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Document management system --- Introduction ---|History": "Beginning in the 1980s, a number of vendors began to develop software systems to manage paper-based documents. These systems dealt with [[paper document]]s, which included not only printed and published documents, but also [[photograph]]s, prints, etc.\n\nLater developers began to write a second type of system which could manage [[electronic document]]s, i.e., all those documents, or files, created on computers, and often stored on users' local [[file-system]]s. The earliest electronic document management (EDM) systems managed either proprietary file types, or a limited number of [[file format]]s. Many of these systems later{{When|date=February 2011}} became known as [[document imaging]] systems, because they focused on the capture, storage, indexing and retrieval of [[image file formats]]. EDM systems evolved to a point where systems could manage any type of file format that could be stored on the network. The applications grew to encompass electronic documents, [[collaboration tool]]s, security, workflow, and [[audit]]ing capabilities.\n\nThese systems enabled an organization to capture faxes and forms, to save copies of the documents as images, and to store the image files in the [[Information repository|repository]] for security and quick retrieval (retrieval made possible because the system handled the extraction of the text from the document in the process of capture, and the text-indexer function provided [[text retrieval|text-retrieval]] capabilities).\n\nWhile many EDM systems store documents in their native file format (Microsoft Word or Excel, PDF), some web-based document management systems are beginning to store content in the form of [[HTML]]. These HTML-based document management systems can act as publishing systems or policy management systems.<ref>[http://www.policystat.com/health-systems-or-networks/ Policy Management System] {{webarchive |url=https://web.archive.org/web/20111029013250/http://www.policystat.com/health-systems-or-networks/ |date=29 October 2011 }}</ref>  Content is captured either by using browser based editors or the importing and conversion of not HTML content.  Storing documents as HTML enables a simpler full-text workflow as most search engines deal with HTML natively.  DMS without an HTML storage format are required to extract the text from the proprietary format making the full text search workflow slightly more complicated.\n\nSearch capabilities including [[Full-text_search#Boolean_queries|boolean queries]], [[cluster analysis]], and [[stemming]]<ref>[http://www.policystat.com/blog/2011/11/08/making-medical-office-policies-easier-to-find-with-stemming/ Stemming: Making searching easier] {{webarchive|url=https://web.archive.org/web/20120111094547/http://www.policystat.com/blog/2011/11/08/making-medical-office-policies-easier-to-find-with-stemming/ |date=11 January 2012 }}</ref> have become critical components of DMS as users have grown use to internet searching and spend less time organizing their content."}},
{"article_title": "Organic farming", "pageid": "72754", "revid": "1062996288", "timestamp": "2021-12-31T17:05:36Z", "history_paths": [["Organic farming --- Introduction ---", "History"]], "categories": ["organic farming", "agroecology", "sustainable technologies", "sustainable food system"], "heading_tree": {"Organic farming --- Introduction ---": {"History": {"Terminology": {}, "Regulations": {}}, "Methods": {"Crop diversity": {}, "Soil management": {}, "Weed management": {}, "Controlling other organisms": {}, "Livestock": {}, "Genetic modification": {}, "Tools": {}}, "Standards": {"Composting": {}}, "Economics": {"Geographic producer distribution": {}, "Growth": {}, "Productivity": {"Long term studies": {}}, "Profitability": {}, "Energy efficiency": {}, "Sales and marketing": {}, "Distributors": {"Direct-to-consumer sales": {}}, "Labour and employment": {}, "World's food security": {}, "Capacity building in developing countries": {"Millennium Development Goals": {}}, "Externalities": {}}, "Issues": {"Environmental impact and emissions": {}, "Nutrient leaching": {}, "Land use": {}, "Pesticides": {}, "Food quality and safety": {}, "Soil conservation": {}, "Biodiversity": {}, "Opposition to labour standards": {}}, "Regional support for organic farming": {"China": {}, "Denmark": {}, "India": {}, "Dominican Republic": {}, "Thailand": {}, "United States": {}, "Sri Lanka": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Organic farming --- Introduction ---|History": "{{Main|History of organic farming}}\n[[Agriculture]] was practiced for thousands of years without the use of artificial chemicals. [[Artificial fertilizer]]s were first developed during the mid-19th century. These [[Fertilizer#History|early fertilizers]] were cheap, powerful, and easy to transport in bulk. Similar advances occurred in chemical [[pesticide]]s in the 1940s, leading to the decade being referred to as the 'pesticide era'.<ref name=Horne2>{{cite book|last=Horne|first=Paul Anthony|title=Integrated pest management for crops and pastures|year=2008|publisher=CSIRO Publishing|isbn=978-0-643-09257-0|page=2|url={{google books |plainurl=y |id=dhO4HAQbNU8C|page=2}}}}</ref> These new agricultural techniques, while beneficial in the short-term, had serious longer-term side-effects such as [[soil compaction]], [[soil erosion|erosion]], and declines in overall [[soil fertility]], along with health concerns about toxic chemicals entering the food supply.<ref name=Stinner2007>{{Cite book |year=2007 |last=Stinner, D.H |chapter=The Science of Organic Farming |editor=William Lockeretz |title=Organic Farming: An International History |publisher=Oxfordshire, UK & Cambridge, Massachusetts: CAB International (CABI) |chapter-url={{google books |plainurl=y |id=25QnL3-njZQC%22Organic}} |access-date=30 April 2013|isbn=978-1-84593-289-3}}</ref>{{rp|10}} In the late 1800s and early 1900s, [[soil biology]] scientists began to seek ways to remedy these side effects while still maintaining higher production.\n\nIn 1921 the founder and pioneer of the organic movement [[Sir Albert Howard|Albert Howard]] and his wife [[Gabrielle Howard]],<ref name="CP_2001">{{cite book |last1=Conford |first1=P. |title=The Origins of the Organic Movement. |date=2001 |publisher=Floris Books |location=Glasgow, Great Britain}}</ref><ref name="GTF_1999">{{cite book |last1=Gieryn |first1=T.F. |title=Cultural Boundaries of Science: Credibility on the Line. |url=https://archive.org/details/culturalboundari0000gier |url-access=registration |date=1999 |publisher=University of Chicago Press |location=Chicago, Il. |pages=[https://archive.org/details/culturalboundari0000gier/page/233 233]\u2013335 }}</ref><ref name="JH_2007">Joseph Heckman, [http://www.westonaprice.org/health-topics/a-history-of-organic-farming-transitions-from-sir-albert-howards-war-in-the-soil-to-the-usda-national-organic-program/ A History of Organic Farming: Transitions from Sir Albert Howard\u2019s War in the Soil to the USDA National Organic Program]</ref> accomplished [[botanist]]s, founded an Institute of Plant Industry to improve traditional farming methods in India. Among other things, they brought improved implements and improved animal husbandry methods from their scientific training; then by incorporating aspects of Indian traditional methods, developed protocols for the rotation of crops, erosion prevention techniques, and the systematic use of composts and manures.<ref>Yeshwant D. Wad, [http://journeytoforever.org/farm_library/howard_memorial.html The Work At Indore]</ref> Stimulated by these experiences of traditional farming, when Albert Howard returned to Britain in the early 1930s<ref>Gabrielle Howard had died while the Howards were still in India.</ref> he began to promulgate a system of organic agriculture.<ref name=vogt>{{cite book |work=Organic Farming: An International History |editor=Lockeretz W |publisher=CABI Publishing |year=2007 |pages=9\u201330 |isbn=9780851998336 |author=Vogt G |title=Chapter 1: The Origins of Organic Farming}}</ref><ref>{{cite journal | last1 = Lotter | first1 = D.W. | year = 2003 | title = Organic agriculture | url = http://www.donlotter.net/lotter_organicag.pdf | journal = Journal of Sustainable Agriculture | volume = 21 | issue = 4 | pages = 59\u2013128 | doi = 10.1300/J064v21n04_06 | s2cid = 216090323 }}</ref><ref name=Kirchmann>{{cite book|last1=Kirchmann|first1=Holger|last2=Bergstrom|first2=Lars|title=Organic Crop Production - Ambitions and Limitations|url={{google books |plainurl=y |id=B6tBN1dyC9oC&pg=PR2}}|date=16 December 2008|publisher=Springer Science & Business Media|isbn=978-1-4020-9316-6|pages=2\u2013}}</ref>\n\nIn 1924 [[Rudolf Steiner]] gave a series of eight lectures on agriculture with a focus on influences of the moon, planets, non-physical beings and elemental forces.<ref>Paull, John (2013) [http://orgprints.org/22491/17/22491.pdf "Koberwitz (Kobierzyce); In the footseps of Rudolf Steiner'"], Journal of Bio-Dynamics Tasmania, 109 (Autumn), pp. 7-11.</ref><ref>Paull, John (2013) [http://orgprints.org/22976/27/22976.pdf "Breslau (Wroc\u0142aw): In the footsteps of Rudolf Steiner"], Journal of Bio- Dynamics Tasmania, 110:10-15.</ref> They were held in response to a request by adherent farmers who noticed degraded soil conditions and a deterioration in the health and quality of crops and livestock resulting from the use of chemical fertilizers.<ref name="Introduction">Diver (1999), [http://attra.ncat.org/attra-pub/biodynamic.html#intro "Introduction"] {{Webarchive|url=https://web.archive.org/web/20110526054008/http://attra.ncat.org/attra-pub/biodynamic.html#intro |date=26 May 2011 }}.</ref> The lectures were published in November 1924; the first English translation appeared in 1928 as ''The Agriculture Course''.<ref>{{cite journal |last=Paull |first=John |year=2011 |url=http://www.jsrp.ro/content/JSRP-Nr3_PAULL |title=The secrets of Koberwitz: the diffusion of Rudolf Steiner's agriculture course and the founding of biodynamic agriculture |journal=Journal of Social Research & Policy |volume=2 |issue=1 |pages=19\u201329 |access-date=6 March 2016 |archive-url=https://web.archive.org/web/20160308223858/http://www.jsrp.ro/content/JSRP-Nr3_PAULL |archive-date=8 March 2016 |url-status=live }}</ref>\n\nIn July 1939, [[Ehrenfried Pfeiffer]], the author of the standard work on [[biodynamic agriculture]] (''Bio-Dynamic Farming and Gardening''),<ref name=Paull2011>{{cite journal |author=Paull, John |year=2011 |title=Biodynamic Agriculture: The Journey from Koberwitz to the World, 1924-1938|url=http://ora.ox.ac.uk/objects/uuid:304a24bf-3961-4798-b13c-9e0a1e2aa339|journal=Journal of Organic Systems |volume=6 |issue=1 |pages=27\u201341}}</ref> came to the UK at the invitation of [[Walter James, 4th Baron Northbourne]] as a presenter at the [[Betteshanger]] Summer School and Conference on Biodynamic Farming at Northbourne's farm in Kent.<ref name=Betteshanger>Paull, John (2011) [http://orgprints.org/19511/1/Paull2011BetteshangerJOS.pdf "The Betteshanger Summer School: Missing link between biodynamic agriculture and organic farming"], Journal of Organic Systems, 6(2):13-26.</ref> One of the chief purposes of the conference was to bring together the proponents of various approaches to organic agriculture in order that they might cooperate within a larger movement. Howard attended the conference, where he met Pfeiffer.<ref>Ehrenfried E. Pfeiffer, [http://journeytoforever.org/farm_library/howard_memorial.html Sir Albert Howard's Deed for Science]</ref> In the following year, Northbourne published his manifesto of organic farming, ''Look to the Land'', in which he coined the term "organic farming". The Betteshanger conference has been described as the 'missing link' between biodynamic agriculture and other forms of organic farming.<ref name=Betteshanger/>\n\nIn 1940 Howard published his ''[[An Agricultural Testament]]''. In this book he adopted Northbourne's terminology of "organic farming".<ref name=Paull>Paull, John (2006) [http://orgprints.org/10138/1/10138.pdf The Farm as Organism: The Foundational Idea of Organic Agriculture] Elementals ~ Journal of Bio-Dynamics Tasmania 83:14\u201318</ref> Howard's work spread widely, and he became known as the "father of organic farming" for his work in applying scientific knowledge and principles to various traditional and natural methods.<ref name=Stinner2007/>{{rp|45}} In the United States [[Jerome Irving Rodale|J.I. Rodale]], who was keenly interested both in Howard's ideas and in biodynamics,<ref name="JH_2007"/> founded in the 1940s both a working organic farm for trials and experimentation, [[The Rodale Institute]], and the [[Rodale Press]] to teach and advocate organic methods to the wider public. These became important influences on the spread of organic agriculture. Further work was done by [[Lady Eve Balfour]] (the [[Haughley Experiment]]) in the United Kingdom, and many others across the world.\n\nThe term "eco-agriculture" was coined in 1970 by [[Charles Walters, Jr.|Charles Walters]], founder of ''Acres Magazine'', to describe agriculture which does not use "man-made molecules of toxic rescue chemistry", effectively another name for organic agriculture.<ref>{{cite web |url=http://www.acresusa.com/eco-agriculture/ |title=What is Eco-Agriculture? |publisher=Acres, USA |access-date=15 October 2019}}</ref>\n\nIncreasing environmental awareness in the general population in modern times has transformed the originally supply-driven organic movement to a demand-driven one. Premium prices and some government subsidies attracted farmers. In the developing world, many producers farm according to traditional methods that are comparable to organic farming, but not certified, and that may not include the latest scientific advancements in organic agriculture. In other cases, farmers in the developing world have converted to modern organic methods for economic reasons.<ref>Paull, John [http://orgprints.org/10949/01/10949.pdf "China's Organic Revolution"], Journal of Organic Systems (2007) 2 (1): 1-11.</ref>\n\n The use of "organic" popularized by Howard and Rodale refers more narrowly to the use of [[Soil organic matter|organic matter]] derived from plant compost and animal manures to improve the [[humus]] content of soils, grounded in the work of early soil scientists who developed what was then called "humus farming". Since the early 1940s the two camps have tended to merge.<ref>{{cite web|last=Nayler|first=Justin|title=Second Thoughts About Organic Agriculture|url=http://www.soilandhealth.org/01aglibrary/Second.Thoughts.pdf|publisher=Soil And Health Library|access-date=11 May 2014|archive-url=https://web.archive.org/web/20140801061226/http://www.soilandhealth.org/01aglibrary/Second.Thoughts.pdf|archive-date=1 August 2014|url-status=dead}}</ref><ref>{{cite web|last=Diver|first=Steve|title=Controlled Microbial Composting and Humus Management: Luebke Compost|url=http://www.ibiblio.org/steved/Luebke/Luebke-compost2.html|access-date=11 May 2014}}</ref>\n\nBiodynamic agriculturists, on the other hand, used the term "organic" to indicate that a farm should be viewed as a living organism,<ref name=Kirchmann/>{{rp|17\u201319}}<ref name=Betteshanger/> in the sense of the following quotation:\n{{quote|1="An organic farm, properly speaking, is not one that uses certain methods and substances and avoids others; it is a farm whose structure is formed in imitation of the structure of a natural system that has the integrity, the independence and the benign dependence of an organism"\n| 2=[[Wendell Berry]], "The Gift of Good Land"}}\nThey based their work on Steiner's spiritually-oriented alternative agriculture which includes various esoteric concepts.\n\n Regulations on "organic" food labels define "organic" primarily in terms of whether "natural" or "artificial" substances were allowed as inputs in the food production process.<ref>{{Cite journal|date=2017-04-01|title=What is this thing called organic? \u2013 How organic farming is codified in regulations|url=https://www.sciencedirect.com/science/article/abs/pii/S0306919216300690|journal=Food Policy|language=en|volume=68|pages=10\u201320|doi=10.1016/j.foodpol.2016.12.009|issn=0306-9192|last1=Seufert|first1=Verena|last2=Ramankutty|first2=Navin|last3=Mayerhofer|first3=Tabea|hdl=2429/70221|hdl-access=free}}</ref>"}},
{"article_title": "Odometer", "pageid": "72877", "revid": "1060651225", "timestamp": "2021-12-16T20:51:59Z", "history_paths": [["Odometer --- Introduction ---", "History"]], "categories": ["american inventions", "ancient greek technology", "chinese inventions", "english inventions", "greek inventions", "length, distance, or range measuring devices", "vehicle parts", "vehicle technology"], "heading_tree": {"Odometer --- Introduction ---": {"History": {"Classical Era": {}, "Imperial China": {"Han Dynasty and Three Kingdoms period": {}, "Song Dynasty": {}}, "Subsequent developments": {}}, "Trip meters": {}, "Clocking/busting miles and legality": {"Prevalence": {}}, "Accuracy": {}, "See also": {}, "References": {}, "Sources": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Odometer --- Introduction ---|History": "{{for|a detailed list of the recorded distances by Alexander's bematists|Bematist}}\n [[File:Hero's odometer, 1st century AD, Alexandria (reconstruction).jpg|thumb|Reconstruction of [[Hero of Alexandria|Hero]]'s odometer, 1st century AD, Alexandria, [[Thessaloniki Science Center and Technology Museum]]]]\nPossibly the first evidence for the use of an odometer can be found in the works of the ancient Roman [[Pliny the Elder|Pliny]] (NH 6. 61-62) and the ancient Greek [[Strabo]] (11.8.9). Both authors list the distances of routes traveled by [[Alexander the Great]] (r. 336-323 BC) as by his [[bematist]]s Diognetus and Baeton. However, the high accuracy of the bematists's measurements rather indicates the use of a mechanical device. For example, the section between the cities Hecatompylos and Alexandria Areion, which later became a part of the [[silk road]], was given by Alexander's bematists as 575 [[Roman mile|Roman miles]] (529 [[Mile|English miles]]) long, that is with a deviation of 0.2% from the actual distance (531 English miles). From the nine surviving bematists' measurements in Pliny's ''[[Natural History (Pliny)|Naturalis Historia]]'' eight show a deviation of less than 5% from the actual distance, three of them being within 1%. Since these minor discrepancies can be adequately explained by slight changes in the tracks of roads during the last 2300 years, the overall accuracy of the measurements implies that the bematists already must have used a sophisticated device for measuring distances, although there is no direct mention of such a device.\n\nAn odometer for measuring distance was first described by [[Vitruvius]] around 27 and 23 BC, although the actual inventor may have been [[Archimedes of Syracuse]] (c. 287 BC \u2013 c. 212 BC) during the [[First Punic War]]. [[Hero of Alexandria]] (10 AD \u2013 70 AD) describes a similar device in chapter 34 of his ''[[Dioptra]]''. The machine was also used in the time of Roman Emperor [[Commodus]] (c. 192 AD), although after this point in time there seems to be a gap between its use in Roman times and that of the 15th century in Western Europe.{{sfn | Needham | 1965 | p=285}}  Some researchers have speculated that the device might have included technology similar to that of the Greek [[Antikythera mechanism]].<ref name="autogenerated188">{{cite journal | bibcode=1981SciAm.245d.188S | title=Vitruvius' Odometer | date=October 1981 | last=Sleeswyk | first=Andr\u00e9 Wegener | journal=[[Scientific American]] | volume=245 | issue=4 | pages=188\u2013200 | issn=0036-8733 | doi=10.1038/scientificamerican1081-188}}</ref>\n\nThe odometer of Vitruvius was based on chariot wheels of 4 Roman feet (1.18 m) diameter turning 400 times in one Roman mile (about 1,480 m). For each revolution a pin on the axle engaged a 400-tooth cogwheel thus turning it one complete revolution per mile. This engaged another gear with holes along the circumference, where pebbles (''[[calculus]]'') were located, that were to drop one by one into a box. The distance traveled would thus be given simply by counting the number of pebbles.<ref name="autogenerated188" />  Whether this instrument was ever built at the time is disputed. [[Leonardo da Vinci]] later tried to build it himself according to the description, but failed.  However, in 1981 engineer Andre Sleeswyk built his own replica, replacing the square-toothed gear designs of da Vinci with the triangular, pointed teeth found in the ''Antikythera mechanism''.  With this modification, the Vitruvius odometer functioned perfectly.<ref name="autogenerated188" />\n\n [[File:Han dynasty odometer cart.jpg|thumb|right|A [[Han Dynasty]] stone rubbing of a horse-drawn odometer cart.]]\n The odometer was also independently invented in [[History of Science and Technology in China|ancient China]],{{sfn | Needham | 1965 | pp=280\u2013286}} possibly by the prolific inventor and early scientist [[Zhang Heng]] (78 AD \u2013 139 AD) of the [[Han Dynasty]]. By the 3rd century (during the [[Three Kingdoms]] Period), the Chinese had termed the device as the 'j\u00ec l\u012d g\u016d ch\u0113' (\u8a18\u91cc\u9f13\u8eca), or '[[li (unit)|li]]-recording drum carriage' (Note: the modern measurement of li = {{Cvt|1640|ft|order=flip}}).{{sfn | Needham | 1965 | p=281}} Chinese texts of the 3rd century tell of the mechanical carriage's functions, and as one li is traversed, a mechanical-driven wooden figure strikes a drum, and when ten li is traversed, another wooden figure would strike a gong or a bell with its mechanical-operated arm.{{sfn | Needham | 1965 | p=281}}\n\nDespite its association with Zhang Heng or even the later [[Ma Jun (mechanical engineer)|Ma Jun]] (c. 200\u2013265), there is evidence to suggest that the invention of the odometer was a gradual process in Han Dynasty China that centered around the ''huang men'' court people (i.e. eunuchs, palace officials, attendants and familiars, actors, acrobats, etc.) that would follow the musical procession of the royal 'drum-chariot'.{{sfn | Needham | 1965 | p=283}} The historian [[Joseph Needham]] asserts that it is no surprise this social group would have been responsible for such a device, since there is already other evidence of their craftsmanship with mechanical toys to delight the emperor and the court. There is speculation that some time in the 1st century BC (during the Western Han Dynasty), the beating of drums and gongs were mechanically-driven by working automatically off the rotation of the road-wheels.{{sfn | Needham | 1965 | p=283}} This might have actually been the design of one Loxia Hong (c. 110 BC), yet by 125 AD the mechanical odometer carriage in China was already known (depicted in a mural of the [[Xiaotang Mountain Han Shrine|Xiaotangshan Tomb]]).{{sfn | Needham | 1965 | p=283}}\n\nThe odometer was used also in subsequent periods of Chinese history. In the historical text of the ''[[Book of Jin|Jin Shu]]'' (635 AD), the oldest part of the compiled text, the book known as the ''Cui Bao'' (c. 300 AD), recorded the use of the odometer, providing description (attributing it to the Western Han era, from 202 BC\u20139 AD).{{sfn | Needham | 1965 | p=282}} The passage in the ''Jin Shu'' expanded upon this, explaining that it took a similar form to the mechanical device of the [[south-pointing chariot]] invented by [[Ma Jun (mechanical engineer)|Ma Jun]] (200\u2013265, see also [[differential (mechanical device)|differential]] gear). As recorded in the ''[[History of Song (Yuan dynasty)|Song Shi]]'' of the [[Song Dynasty]] (960-1279 AD), the odometer and south-pointing chariot were combined into one wheeled device by engineers of the 9th century, 11th century, and 12th century. The ''[[Sunzi Suanjing]]'' (Master Sun's Mathematical Manual), dated from the 3rd century to 5th century, presented a mathematical problem for students involving the odometer. It involved a given distance between two cities, the small distance needed for one rotation of the carriage's wheel, and the posed question of how many rotations the wheels would have in all if the carriage was to travel between point A and B.{{sfn | Needham | 1965 | p=282}}\n\n The historical text of the ''[[History of Song (Yuan dynasty)|Song Shi]]'' (1345 AD), recording the people and events of the Chinese [[Song Dynasty]] (960\u20131279), also mentioned the odometer used in that period. However, unlike written sources of earlier periods, it provided a much more thoroughly detailed description of the device that harkens back to its ancient form ([[Wade-Giles]] spelling):\n\n<blockquote>\nThe odometer. [The mile-measuring carriage] is painted red, with pictures of flowers and birds on the four sides, and constructed in two storeys, handsomely adorned with carvings. At the completion of every li, the wooden figure of a man in the lower storey strikes a drum; at the completion of every ten li, the wooden figure in the upper storey strikes a bell. The carriage-pole ends in a phoenix-head, and the carriage is drawn by four horses. The escort was formerly of 18 men, but in the 4th year of the Yung-Hsi reign-period (987 AD) [[Emperor Taizong of Song|the emperor Thai Tsung]] increased it to 30. In the 5th year of the Thien-Sheng reign-period (1027 AD) the Chief Chamberlain Lu Tao-lung presented specifications for the construction of odometers as follows:{{sfn | Needham | 1965 | p=283}}\n</blockquote>\n\nWhat follows is a long dissertation made by the Chief Chamberlain Lu Daolong on the ranging measurements and sizes of wheels and gears, along with a concluding description at the end of how the device ultimately functions:\n\n<blockquote>\nThe vehicle should have a single pole and two wheels. On the body are two storeys, each containing a carved wooden figure holding a drumstick. The road-wheels are each 6 ft in diameter, and 18 ft in circumference, one evolution covering 3 paces. According to ancient standards the pace was equal to 6 ft and 300 paces to a li; but now the li is reckoned as 360 paces of 5 ft each.{{sfn | Needham | 1965 | p=283}}\n</blockquote>\n\n[Note: the measurement of the Chinese-mile unit, the li, was changed over time, as the li in Song times differed from the length of a li in Han times.]\n\n<blockquote>\nThe vehicle wheel (li lun) is attached to the left road-wheel; it has a diameter of 1.38 ft with a circumference of 4.14 ft, and has 18 cogs (chhih) 2.3 inches apart. There is also a lower horizontal wheel (hsia phing lun), of diameter 4.14 ft and circumference 12.42 ft, with 54 cogs, the same distance apart as those on the vertical wheel (2.3 inches). (This engages with the former.){{sfn | Needham | 1965 | p=283}}\n</blockquote>\n\n<blockquote>\nUpon a vertical shaft turning with this wheel, there is fixed a bronze "turning-like-the-wind wheel" (hsuan feng lun) which has (only) 3 cogs, the distance between these being 1.2 inches. (This turns the following one.) In the middle is a horizontal wheel, 4 ft in diameter, and 12 ft circumference, with 100 cogs, the distance between these cogs being the same as on the "turning-like-the-wind wheel" (1.2 inches).{{sfn | Needham | 1965 | p=284}}\n</blockquote>\n\n<blockquote>\nNext, there is fixed (on the same shaft) a small horizontal wheel (hsiao phing lun) 3.3 inches in diameter and 1 ft in circumference, having 10 cogs 1.5 inches apart. (Engaging with this) there is an upper horizontal wheel (shang phing lun) having a diameter of 3.3 ft and a circumference of 10 ft, with 100 cogs, the same distance apart as those of the small horizontal wheel (1.5 inches).{{sfn | Needham | 1965 | p=284}}\n</blockquote>\n\n<blockquote>\nWhen the middle horizontal wheel has made 1 revolution, the carriage will have gone 1 li and the wooden figure in the lower story will strike the drum. When the upper horizontal wheel has made 1 revolution, the carriage will have gone 10 li and the figure in the upper storey will strike the bell. The number of wheels used, great and small, is 8 inches in all, with a total of 285 teeth. Thus the motion is transmitted as if by the links of a chain, the "dog-teeth" mutually engaging with each other, so that by due revolution everything comes back to its original starting point (ti hsiang kou so, chhuan ya hsiang chih, chou erh fu shih).{{sfn | Needham | 1965 | p=284}}\n</blockquote>\n\n [[File:Hubodometer on a wheel of a semitrailer.jpg|thumb|A [[Hubodometer]] on a wheel of a semitrailer]]\n[[File:Smiths speedo.jpg|thumb|right|A Smiths speedometer from the 1920s showing odometer and trip meter.]]\nOdometers were first developed in the 1600s for wagons and other horse-drawn vehicles in order to measure distances traveled.\n\n[[Levinus Hulsius]] published the odometer in 1604 in his work ''Gr\u00fcndtliche Beschreibung de\u00df Diensthafften und Nutzbahrn Instruments Viatorii oder Wegz\u00e4hlers, So zu Fu\u00df, zu Pferdt unnd zu Fu\u00dfen gebraucht werden kann, damit mit geringer m\u00fche zu wissen, wie weit man gegangen, geritten, oder gefahren sey: als auch zu erfahren, ohne messen oder zehlen, wie weit von einem Orth zum andern. Daneben wird auch der grosse verborgene Wegweiser angezeiget und vermeldet''.{{sfn | Kern | 2010 | p=470}}\n\nIn 1645, the French mathematician [[Blaise Pascal]] invented the ''[[pascaline]]''. Though not an odometer, the ''pascaline'' utilized gears to compute measurements.  Each gear contained 10 teeth.  The first gear advanced the next gear one position when moved one complete revolution, the same principle employed on modern mechanical odometers.\n\nOdometers were developed for ships in 1698 with the odometer invented by the Englishman [[Thomas Savery]].  [[Benjamin Franklin]], U.S. statesman and the first [[United States Postmaster General|Postmaster General]], built a prototype odometer in 1775 that he attached to his carriage to help measure the [[Distance|mileage]] of postal routes.<ref>{{cite web | access-date=2019-10-10 | archive-date=2015-08-29 | archive-url=https://web.archive.org/web/20150829041636/http://learn.fi.edu/franklin/inventor/inventor.html | url=http://learn.fi.edu/franklin/inventor/inventor.html | title=Benjamin Franklin and His Inventions | url-status=dead | website=learn.fi.edu}}</ref>  In 1847, [[William Clayton (Mormon)|William Clayton]] and [[Orson Pratt]], pioneers of [[The Church of Jesus Christ of Latter-day Saints]], first implemented the ''Roadometer'' they had invented earlier (a version of the modern odometer), which they attached to a wagon used by American settlers heading west.<ref>{{cite web | access-date=2019-10-10 | url=https://www.thoughtco.com/history-of-odometers-4074178 | title=The History of the Odometer | date=2019-04-06 | last=Bellis | first=Mary | language=en | website=ThoughtCo}}</ref>  It recorded the distance traveled each day by the [[wagon trains]].   The ''Roadometer'' used two gears and was an early example of an odometer with pascaline-style gears in actual use.<ref>{{cite web | access-date=2021-04-06 | url=https://history.churchofjesuschrist.org/content/museum/museum-treasures-odometer?lang=eng | title=One Tool That Built the West: Orson Pratt's Odometer | date=2018-09-01 | language=en | website=ChurchOfJesusChrist}}</ref>\n\nIn 1895, Curtis Hussey Veeder invented the ''Cyclometer''.<ref>{{cite journal | hdl=2027/njp.32101048981896 | url=https://hdl.handle.net/2027/njp.32101048981896?urlappend=%3Bseq=210 | title=Personal Notes of the Automobile Trade | date=1917-05-17 | journal=The Horseless Age | volume=40 | issue=4 | page=58}}</ref><ref>{{cite web | url=http://www.ctheritage.org/encyclopedia/topicalsurveys/inventors.htm | title=Connecticut Inventors | publisher=Connecticut Humanities Council | access-date=2011-03-01 | author=Robert Asher | archive-url=https://web.archive.org/web/20110518133818/http://www.ctheritage.org/encyclopedia/topicalsurveys/inventors.htm | archive-date=2011-05-18 | url-status=dead | year=2003}}</ref>  The ''Cyclometer'' was a mechanical device that counted the number of rotations of a bicycle wheel.<ref>{{cite web | access-date=2019-10-10 | url=https://www.veeder.com/us/company-overview | title=Company Overview | website=Veeder-Root}}</ref>  A flexible cable transmitted the number of rotations of the wheel to an analog odometer visible to the rider, which converted the wheel rotations into the number of miles traveled according to a predetermined formula.\n\nIn 1903 [[Arthur Pratt Warner|Arthur P.]] and Charles H. Warner, two brothers from Beloit, Wisconsin, introduced their patented ''Auto-meter''.  The ''Auto-Meter'' used a magnet attached to a rotating shaft to induce a magnetic pull upon a thin metal disk.  Measuring this pull provided accurate measurements of both distance and speed information to automobile drivers in a single instrument.  The Warners sold their company in 1912 to the Stewart & Clark Company of Chicago.  The new firm was renamed the Stewart-Warner Corporation. By 1925, Stewart-Warner odometers and trip meters were standard equipment on the vast majority of automobiles and motorcycles manufactured in the United States.\n\nBy the early 2000s, mechanical odometers would be phased out on cars from major manufacturers. The [[Pontiac Grand Prix#Sixth generation (1997\u20132003)|Pontiac Grand Prix]] was the last GM car sold in the US to offer a mechanical odometer in 2003, the Canadian-built [[Ford Crown Victoria#Second generation (1998\u20132012)|Ford Crown Victoria]] and [[Mercury Grand Marquis#Fourth generation (2003\u20132011)|Mercury Grand Marquis]] were the last Fords sold with one in 2005. {{citation needed|date=October 2016}}"}},
{"article_title": "Astrolabe", "pageid": "73664", "revid": "1061698841", "timestamp": "2021-12-23T09:56:21Z", "history_paths": [["Astrolabe --- Introduction ---", "History"]], "categories": ["analog computers", "ancient greek astronomy", "greek inventions", "ancient greek technology", "astrometry", "astronomical instruments", "historical scientific instruments", "inclinometers", "islamic astronomy", "islamic technology", "mechanical calculators", "navigational equipment"], "heading_tree": {"Astrolabe --- Introduction ---": {"Applications": {}, "Etymology": {}, "History": {"Ancient world": {}, "Medieval era": {}, "Astrolabes and clocks": {}}, "Construction": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Astrolabe --- Introduction ---|History": "An early astrolabe was invented in the [[Hellenistic civilization]] by [[Apollonius of Perga]] between 220 and 150 BC, often attributed to [[Hipparchus]]. The astrolabe was a marriage of the [[planisphere]] and [[dioptra]], effectively an analog calculator capable of working out several different kinds of problems in astronomy. [[Theon of Alexandria]] ({{circa|335}} \u2013 {{circa|405}}) wrote a detailed treatise on the astrolabe, and Lewis{{sfn|Lewis|2001}} argues that [[Ptolemy]] used an astrolabe to make the astronomical observations recorded in the ''[[Tetrabiblos]]''. The invention of the plane astrolabe is sometimes wrongly attributed to Theon's daughter [[Hypatia]] ({{circa|350\u2013370}}; died 415 AD),<ref>Michael Deakin (August 3, 1997). "Ockham's Razor: Hypatia of Alexandria". ABC Radio. Retrieved July 10, 2014.</ref><ref name="Theodore">{{cite book|last=Theodore|first=Jonathan|date=2016|title=The Modern Cultural Myth of the Decline and Fall of the Roman Empire|url=https://books.google.com/books?id=3QPWDAAAQBAJ&pg=PA183|location=Manchester, England|publisher=Palgrave, Macmillan|page=183|isbn=978-1-137-56997-4}}</ref><ref name="Deakin2007">{{cite book|last=Deakin|first=Michael A. B.|date=2007|title=Hypatia of Alexandria: Mathematician and Martyr|url=https://books.google.com/books?id=P6X1DJ7UIb4C&pg=PA135|location=Amherst, New York|publisher=Prometheus Books|pages=102\u2013104|isbn=978-1-59102-520-7}}</ref><ref name="Bradley">{{cite book|last=Bradley|first=Michael John|date=2006|title=The Birth of Mathematics: Ancient Times to 1300|url=https://books.google.com/books?id=EIdtVPeD7GcC|location=New York City, New York|publisher=Infobase Publishing|page=63|isbn=9780816054237}}</ref> but it is, in fact, known to have already been in use at least 500 years before Hypatia was born.<ref name="Theodore"/><ref name="Deakin2007"/><ref name="Bradley"/> The misattribution comes from a misinterpretation of a statement in a letter written by Hypatia's pupil [[Synesius]] ({{circa|373}} \u2013 {{circa|414}}),<ref name="Theodore"/><ref name="Deakin2007"/><ref name="Bradley"/> which mentions that Hypatia had taught him how to construct a plane astrolabe, but does not state anything about her having invented it herself.<ref name="Theodore"/><ref name="Deakin2007"/><ref name="Bradley"/>\n\nAstrolabes continued in use in the Greek-speaking world throughout the [[Byzantine Empire|Byzantine]] period. About 550 AD, Christian philosopher [[John Philoponus]] wrote a treatise on the astrolabe in Greek, which is the earliest extant treatise on the instrument.{{efn|Modern editions of [[John Philoponus]]' treatise on the astrolabe are ''De usu astrolabii eiusque constructione libellus'' (On the Use and Construction of the Astrolabe), ed. Heinrich Hase, Bonn: E. Weber, 1839, {{OCLC|165707441}} (or id. Rheinisches Museum f\u00fcr Philologie 6 (1839): 127\u201371); repr. and translated into French by Alain Philippe Segonds, ''Jean Philopon, trait\u00e9 de l'astrolabe,'' Paris: Librairie Alain Brieux, 1981, {{OCLC|10467740}}; and translated into English by H.W. Green in R.T. Gunther, ''The Astrolabes of the World'', Vol. 1/2, Oxford, 1932, {{OL|18840299M}} repr. London: Holland Press, 1976, {{OL|14132393M }} pp. 61\u201381.}} Mesopotamian bishop [[Severus Sebokht]] also wrote a treatise on the astrolabe in the [[Syriac language]] in the mid-7th century.{{efn|{{cite book| publisher = Routledge and Kegan Paul| last = O'Leary| first = De Lacy|author-link=De Lacy O'Leary| title = How Greek Science Passed to the Arabs| date = 1948 |url=http://www.aina.org/books/hgsptta.htm}} "The most distinguished Syriac scholar of this later period was [[Severus Sebokht]] (d. 666\u20137), Bishop of Kennesrin. [...] In addition to these works [...] he also wrote on astronomical subjects (Brit. Mus. Add. 14538), and composed a treatise on the astronomical instrument known as the astrolabe, which has been edited and published by F. Nau (Paris, 1899)." <br />Severus' treatise was translated by Jessie Payne Smith Margoliouth in R.T. Gunther, ''Astrolabes of the World'', Oxford, 1932, pp. 82\u2013103.}} Sebokht refers to the astrolabe as being made of brass in the introduction of his treatise, indicating that metal astrolabes were known in the Christian East well before they were developed in the Islamic world or in the Latin West.<ref>{{cite web |first=Severus |last=Sebokht |title=Description of the astrolabe |url=  http://www.tertullian.org/fathers/severus_sebokht_astrolabe_01_trans.htm |publisher=Tertullian.org}}</ref>\n\nThe first Renaissance treatises dealing with scientific problems were based on earlier classical works and were often concerned with Ptolemaic doctrines. Among these, the most influential was the astronomical section of Regiomontanus' Almanacium, written in 1472 and published in Venice in 1506.\n\n Astrolabes were further developed in the [[Islamic Golden Age|medieval Islamic world]], where [[Astronomy in medieval Islam|Muslim astronomers]] introduced angular scales to the design,<ref>See p. 289 of {{Citation\n| doi = 10.1088/1475-4878/24/5/302| issn = 1475-4878| volume = 24| issue = 5| pages = 289\u2013303| last = Martin| first = L. C.| title = Surveying and navigational instruments from the historical standpoint| journal = Transactions of the Optical Society| date = 1923| postscript = .|bibcode = 1923TrOS...24..289M }}</ref> adding circles indicating [[azimuth]]s on the [[horizon]].<ref>{{citation|title=The Mathematics of Egypt, Mesopotamia, China, India, and Islam: a Sourcebook|editor-first=Victor J.|editor-last=Katz|first=J. Lennart|last=Berggren|chapter=Mathematics in Medieval Islam|chapter-url=https://books.google.com/books?id=3ullzl036UEC&pg=PA519|publisher=[[Princeton University Press]]|date=2007|isbn=978-0-691-11485-9|page=519}}</ref> It was widely used throughout the Muslim world, chiefly as an [[Geography in medieval Islam|aid to navigation]] and as a way of finding the [[Qibla]], the direction of [[Mecca]]. Eighth-century [[Mathematics in medieval Islam|mathematician]] [[Muhammad al-Fazari]] is the first person credited with building the astrolabe in the Islamic world.<ref>[[Richard Nelson Frye]]: ''Golden Age of Persia''. p. 163</ref>\n\nThe mathematical background was established by Muslim astronomer [[Muhammad ibn J\u0101bir al-Harr\u0101n\u012b al-Batt\u0101n\u012b|Albatenius]] in his treatise ''Kitab az-Zij'' (c. 920 AD), which was translated into Latin by [[Plato Tiburtinus]] (''De Motu Stellarum''). The earliest surviving astrolabe is dated [[Islamic calendar|AH]] 315 (927\u201328 AD).<ref>{{cite web | title=The Earliest Surviving Dated Astrolabe | website=HistoryOfInformation.com | url=http://www.historyofinformation.com/expanded.php?id=2340}}</ref> In the Islamic world, astrolabes were used to find the times of sunrise and the rising of fixed stars, to help schedule morning prayers ([[salat]]). In the 10th century, [[al-Sufi]] first described over 1,000 different uses of an astrolabe, in areas as diverse as [[astronomy]], [[Islamic astrology|astrology]], [[Mariner's astrolabe|navigation]], [[surveying]], timekeeping, prayer, [[Salat]], [[Qibla]], etc.<ref>Dr. Emily Winterburn ([[National Maritime Museum]]), [https://muslimheritage.com/using-an-astrolabe/ Using an Astrolabe], Foundation for Science Technology and Civilisation, 2005.</ref><ref>{{cite book |last1=Lachi\u00e8z-Rey |first1=Marc |last2=Luminet |first2=Jean-Pierre |others=Trans. Joe Laredo |title=Celestial Treasury: From the Music of Spheres to the Conquest of Space |date=2001 |publisher=Cambridge University Press |location=Cambridge, UK |isbn=978-0-521-80040-2 |page=74}}</ref>\n\nThe [[spherical astrolabe]] was a variation of both the astrolabe and the [[armillary sphere]], invented during the [[Middle Ages]] by astronomers and [[Inventions in the Muslim world|inventors]] in the Islamic world.{{efn|{{cite journal|first=Emilie|last=Savage-Smith|year=1993|title=Book Reviews|journal=Journal of Islamic Studies|volume=4|issue=2|pages=296\u2013299|doi=10.1093/jis/4.2.296|quote=There is no evidence for the Hellenistic origin of the spherical astrolabe, but rather evidence so far available suggests that it may have been an early but distinctly Islamic development with no Greek antecedents.}}}}\nThe earliest description of the spherical astrolabe dates back to [[Al-Nayrizi]] ([[floruit|fl.]] 892\u2013902). In the 12th century, [[Sharaf al-D\u012bn al-T\u016bs\u012b]] invented the ''linear astrolabe'', sometimes called the "staff of al-Tusi", which was "a simple wooden rod with graduated markings but without sights. It was furnished with a plumb line and a double chord for making angular measurements and bore a perforated pointer".<ref name=MacTutor>{{MacTutor|id=Al-Tusi_Sharaf|title=Sharaf al-Din al-Muzaffar al-Tusi}}</ref> The geared mechanical astrolabe was invented by Abi Bakr of [[Isfahan]] in 1235.<ref name=Bedini>{{cite journal|author-link1=Silvio Bedini|first1=Silvio A.|last1=Bedini|author-link2=Francis Maddison|first2=Francis R.|last2=Maddison|year=1966|title=Mechanical Universe: The Astrarium of Giovanni de' Dondi|journal=Transactions of the American Philosophical Society|volume=56|issue=5|pages=1\u201369|jstor=1006002|doi=10.2307/1006002}}</ref>\n\nThe first known metal astrolabe in Western Europe is the Destombes astrolabe made from brass in the eleventh century in Portugal.<ref>{{cite web|url=http://www.qantara-med.org/qantara4/public/show_document.php?do_id=1379&lang=en |title=Qantara \u2013 'Carolingian' astrolabe |publisher=Qantara-med.org |access-date=2013-11-07}}</ref><ref>Nancy Marie Brown (2010), "The Abacus and the Cross". Page 140.  Basic Books.  {{ISBN|978-0-465-00950-3}}</ref> Metal astrolabes avoided the warping that large wooden ones were prone to, allowing the construction of larger and therefore more accurate instruments. Metal astrolabes were heavier than wooden instruments of the same size, making it difficult to use them in navigation.<ref>{{cite book|title=Toward the Setting Sun: Columbus, Cabot, Vespucci, and the Race for America|first=David|last=Boyle|publisher=Bloomsbury Publishing USA|date=2011|isbn=9780802779786|page=253|url=https://books.google.com/books?id=x92SNeDpKqsC&pg=PA253}}.</ref>\n\n[[Herman Contractus]] of [[Reichenau Abbey]], examined the use of the astrolabe in ''Mensura Astrolai'' during the 11th century.<ref>{{Cite book|title=Encyclopedia of world trade : from ancient times to the present|publisher=Routledge|editor=Northrup, Cynthia Clark |year=2015|isbn=978-0765680587|edition=Enhanced Credo |location=Armonk, New York|pages=[https://archive.org/details/encyclopediaofwo0000unse_d8h7/page/72 72]|oclc=889717964|url=https://archive.org/details/encyclopediaofwo0000unse_d8h7/page/72}}</ref> [[Peter of Maricourt]] wrote a treatise on the construction and use of a universal astrolabe in the last half of the 13th century entitled ''Nova compositio astrolabii particularis''. Universal astrolabes can be found at the History of Science Museum in Oxford.<ref>{{Cite web|title=Introduction|url=https://www.mhs.ox.ac.uk/astrolabe/|date=2006|website=The Astrolabe: an Online Resource|access-date=2020-05-15}}</ref> David A. King, historian of Islamic instrumentation, describes the universal astrolobe designed by Ibn al-Sarraj of [[Aleppo]] (aka Ahmad bin Abi Bakr; fl. 1328) as "the most sophisticated astronomical instrument from the entire Medieval and Renaissance periods".<ref>{{cite book|last=Harley|first=J. B.|title=The history of cartography|date=1992|publisher=Univ. of Chicago Press|location=Chicago|isbn=0-226-31635-1|author2=Woodward, David|page=31}}</ref>\n\nEnglish author [[Geoffrey Chaucer]] (c. 1343\u20131400) compiled ''[[A Treatise on the Astrolabe]]'' for his son, mainly based on a work by [[Mashallah ibn Athari|Messahalla]] or [[Ibn al-Saffar]].<ref>{{Cite journal| volume = 31| issue = 106| pages = 42\u201362| last = Kunitzsch| first = Paul| title = On the authenticity of the treatise on the composition and use of the astrolabe ascribed to Messahalla| journal = Archives Internationales d'Histoire des Sciences Oxford| date = 1981}}</ref><ref>{{Cite book| publisher = Springer Science & Business Media| isbn = 978-1-4020-4559-2| last = Selin| first = Helaine| title = Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures| url = https://archive.org/details/encyclopaediahis00seli| url-access = limited| date = 2008-03-12|page=[https://archive.org/details/encyclopaediahis00seli/page/n1347 1335]|quote=Paul Kunitzsch has recently established that the Latin treatise on the astrolabe long ascribed to Ma'sh'allah and translated by John of Seville is in fact by Ibn al-Saffar, a disciple of Maslama al-Majriti.}}</ref> The same source was translated by French astronomer and astrologer P\u00e9lerin de Prusse and others. The first printed book on the astrolabe was ''Composition and Use of Astrolabe'' by [[Christian of Prachatice]], also using Messahalla, but relatively original.\n\nIn 1370, the first Indian treatise on the astrolabe was written by the [[Jainism|Jain]] astronomer [[Mahendra Suri]], titled ''Yantrar\u0101ja''.<ref>{{Citation | editor1-first=Thomas|editor1-last=Glick|editor2-first=Steven J.|editor2-last=Livesey|editor3-first=Faith|editor3-last=Wallis | title = Medieval Science, Technology, and Medicine: An Encyclopedia | date = 2005 | publisher = Routledge | isbn = 0-415-96930-1 | page = 464 | display-editors = 1 | url=https://books.google.com/books?id=SaJlbWK_-FcC&pg=PA464 }}</ref>\n\nA simplified astrolabe, known as a ''balesilha'', was used by sailors to get an accurate reading of latitude while out to sea. The use of the ''balesilha'' was promoted by [[Prince Henry the Navigator|Prince Henry]] (1394\u20131460) while out navigating for Portugal.<ref>{{Cite book|title=Encyclopedia of world trade : from ancient times to the present|publisher=Routledge|editor=Northrup, Cynthia Clark |year=2015|isbn=978-0765680587|edition=[Enhanced Credo edition]|location=Armonk, New York|pages=[https://archive.org/details/encyclopediaofwo0000unse_d8h7/page/460 460]|oclc=889717964|url=https://archive.org/details/encyclopediaofwo0000unse_d8h7/page/460}}</ref>\n\nThe astrolabe was almost certainly first brought north of the Pyrenees by Gerbert of Aurillac (future [[Pope Sylvester II]]), where it was integrated into the [[quadrivium]] at the school in Reims, France sometime before the turn of the 11th century.<ref>Nancy Marie Brown (2010), "The Abacus and the Cross".  Page 143. basic Books. {{ISBN|978-0-465-00950-3}}</ref> In the 15th century, French instrument maker Jean Fusoris (c. 1365\u20131436) also started remaking and selling astrolabes in his shop in [[Paris]], along with portable sundials and other popular scientific devices of the day.  Thirteen of his astrolabes survive to this day.<ref>{{cite book |title=The Biographical Encyclopedia of Astronomers |last=Hockey |first=Thomas |date=2009 |publisher=[[Springer Publishing]] |isbn=978-0-387-31022-0 |access-date=August 22, 2012 |url=http://www.springerreference.com/docs/html/chapterdbid/58493.html}}</ref>  One more special example of craftsmanship in early 15th-century Europe is the astrolabe designed by Antonius de Pacento and made by Dominicus de Lanzano, dated 1420.<ref>Ralf Kern (2010), ''Wissenschaftliche Instrumente in ihrer Zeit''. Band 1: Vom Astrolab zum mathematischen Besteck. Cologne, S. 204. {{ISBN|978-3-86560-865-9}}</ref>\n\nIn the 16th century, [[Johannes St\u00f6ffler]] published ''Elucidatio fabricae ususque astrolabii'', a manual of the construction and use of the astrolabe. Four identical 16th-century astrolabes made by [[Georg Hartmann]] provide some of the earliest evidence for [[batch production]] by [[division of labor]].\n\n{{Gallery\n|title=Medieval astrolabes\n|align=center\n|File:Tusi manus.jpg|A treatise explaining the importance of the astrolabe by [[Nasir al-Din al-Tusi]], Persian scientist\n|File:Jean Fusoris planispheric astrolabe in Putnam Gallery, 2009-11-24.jpg|Astrolabe of {{Interlanguage link multi|Jean Fusoris|fr}}, made in [[Paris]], 1400\n|File:Astrolabe-Persian-18C.jpg|An 18th-century [[Persia]]n astrolabe\n|File:Astrolabe, 18th century, disassembled.jpg|Disassembled 18th-century astrolabe\n|File:Astrolabium im Mathematisch-Physikalischen Salon (Zwinger, Dresden).jpg|Exploded view of an astrolabe\n|File:Astrolabe - Stereographic projection on tympan.gif|Animation showing how [[celestial coordinate system|celestial]] and [[geographic coordinate system|geographic coordinates]] are mapped on an astrolabe's tympan through a [[stereographic projection]]. Hypothetical tympan ([[40th parallel north|40\u00b0 north latitude]]) of a 16th-century European [[planisphere|planispheric]] astrolabe.\n|File:Astrolabium Masha'allah Public Library Brugge Ms. 522.tif|Astrolabium Masha'Allah {{Interlanguage link multi|Public Library Bruges|nl|3=Openbare Bibliotheek Brugge}} Ms. 522\n}}\n\n \n[[File:Het gebruik van het astrolabium door Amerigo Vespucci, Jan Collaert II, Museum Plantin-Moretus, PK.OPB.0186.018.jpg|thumb|[[Amerigo Vespucci]] observing the [[Crux|Southern Cross]] with an Astrolabium, by [[Jan Collaert II]]. [[Museum Plantin-Moretus]], [[Antwerp]], Belgium.]]\n\nMechanical [[astronomical clock]]s were initially influenced by the astrolabe; they could be seen in many ways as clockwork astrolabes designed to produce a continual display of the current position of the sun, stars, and planets. For example, [[Richard of Wallingford]]'s clock (c. 1330) consisted essentially of a star map rotating behind a fixed rete, similar to that of an astrolabe.{{sfn|North| 2005}}\n\nMany astronomical clocks use an astrolabe-style display, such as the famous [[Prague Orloj|clock at Prague]], adopting a stereographic projection (see below) of the ecliptic plane. In recent times, astrolabe watches have become popular. For example, Swiss watchmaker [[Ludwig Oechslin|Dr. Ludwig Oechslin]] designed and built an astrolabe wristwatch in conjunction with [[Ulysse Nardin]] in 1985.<ref>{{cite web |url=http://www.ulysse-nardin.ch/en/swiss_watch_manufacturer/Collection/Archive/Astrolabium_G._Galilei.html |url-status=dead |archive-url=https://web.archive.org/web/20110102024043/http://www.ulysse-nardin.ch/en/swiss_watch_manufacturer/Collection/Archive/Astrolabium_G._Galilei.html |archive-date=2 January 2011 |title=Astrolabium G. Galilei |website=Ulysse Nardin}}</ref> Dutch watchmaker Christaan van der Klauuw also manufactures astrolabe watches today.<ref>{{cite web |url=http://www.klaauw.com/ |title=Christaan van der Klauuw}}</ref>"}},
{"article_title": "Electrocardiography", "pageid": "76988", "revid": "1060476672", "timestamp": "2021-12-15T19:37:16Z", "history_paths": [["Electrocardiography --- Introduction ---", "History"]], "categories": ["cardiac electrophysiology", "cardiac procedures", "electrodiagnosis", "electrophysiology", "mathematics in medicine", "medical tests", "dutch inventions", "science and technology in the netherlands", "biology in the netherlands"], "heading_tree": {"Electrocardiography --- Introduction ---": {"Medical uses": {"Screening": {}}, "Electrocardiograph machines": {"Cardiac monitors": {}}, "Electrodes and leads": {"Limb leads": {}, "Augmented limb leads": {}, "Precordial leads": {}, "Specialized leads": {}, "Lead locations on an ECG report": {}, "{{anchor|Lead groups}}Contiguity of leads": {}}, "Electrophysiology": {}, "Interpretation": {"Theory": {}, "Background grid": {}, "Rate and rhythm": {}, "Axis": {}, "Amplitudes and intervals": {}, "Limb leads and electrical conduction through the heart": {}, "Ischemia and infarction": {}, "Artifacts": {}}, "Diagnosis": {}, "History": {"Etymology": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Electrocardiography --- Introduction ---|History": "[[File:Willem Einthoven ECG.jpg|thumb|An early commercial ECG device (1911)]]\n[[File:BASA-532K-1-2-15-Ran Bosilek.jpg|thumb|ECG from 1957]]\n* In 1872, [[Alexander Muirhead]] is reported to have attached wires to the wrist of a patient with fever to obtain an electronic record of their heartbeat.<ref>{{Cite ODNB |url=http://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-37794 |title=Muirhead, Alexander (1848\u20131920), electrical engineer |last=Birse |first=Ronald M. |date=2004-09-23 |editor-last=Knowlden |editor-first=Patricia E. |language=en |doi=10.1093/ref:odnb/37794 |access-date=2020-01-20}}</ref>\n* In 1882, [[John Burdon-Sanderson]] working with frogs, was the first to appreciate that the interval between variations in potential was not electrically quiescent and coined the term "isoelectric interval" for this period.<ref>{{Cite journal |last=Rogers |first=Mark C. |date=1969 |title=Historical Annotation: Sir John Scott Burdon-Sanderson (1828-1905) A Pioneer in Electrophysiology |journal=Circulation |language=en |volume=40 |issue=1 |pages=1\u20132 |doi=10.1161/01.CIR.40.1.1 |issn=0009-7322 |pmid=4893441|doi-access=free }}</ref>\n* In 1887, [[Augustus Desir\u00e9 Waller|Augustus Waller]]<ref name="Waller_1887">{{Cite journal |last=Waller AD |year=1887 |title=A demonstration on man of electromotive changes accompanying the heart's beat |journal=J Physiol |volume=8 |issue=5 |pages=229\u201334 |doi=10.1113/jphysiol.1887.sp000257 |pmc=1485094 |pmid=16991463}}</ref> invented an ECG machine consisting of a [[lippmann electrometer|Lippmann capillary electrometer]] fixed to a projector. The trace from the heartbeat was projected onto a photographic plate that was itself fixed to a toy train. This allowed a heartbeat to be recorded in real time.\n* In 1895, [[Willem Einthoven]] assigned the letters P, Q, R, S, and T to the deflections in the theoretical waveform he created using equations which corrected the actual waveform obtained by the capillary electrometer to compensate for the imprecision of that instrument. Using letters different from A, B, C, and D (the letters used for the capillary electrometer's waveform) facilitated comparison when the uncorrected and corrected lines were drawn on the same graph.<ref name=naming/> Einthoven probably chose the initial letter P to follow the example set by [[Descartes]] in [[geometry]].<ref name=naming/> When a more precise waveform was obtained using the string galvanometer, which matched the corrected capillary electrometer waveform, he continued to use the letters P, Q, R, S, and T,<ref name="naming">{{Cite journal |last=Hurst JW |date=3 November 1998 |title=Naming of the Waves in the ECG, With a Brief Account of Their Genesis |journal=Circulation |volume=98 |issue=18 |pages=1937\u201342 |doi=10.1161/01.CIR.98.18.1937 |pmid=9799216|doi-access=free }}</ref> and these letters are still in use today. Einthoven also described the electrocardiographic features of a number of cardiovascular disorders.\n* In 1897, the string galvanometer was invented by the French engineer [[Cl\u00e9ment Ader]].<ref>{{Cite journal |last=Interwoven W |year=1901 |title=Un nouveau galvanometre |journal=Arch Neerl Sc Ex Nat |volume=6 |page=625}}</ref>\n* In 1901, Einthoven, working in [[Leiden]], the [[Netherlands]], used the [[string galvanometer]]: the first practical ECG.<ref>{{Cite journal |vauthors=Rivera-Ruiz M, Cajavilca C, Varon J |date=29 September 1927 |title=Einthoven's String Galvanometer: The First Electrocardiograph |journal=Texas Heart Institute Journal  |volume=35 |issue=2 |pages=174\u201378 |pmc=2435435 |pmid=18612490}}</ref> This device was much more sensitive than the capillary electrometer Waller used.\n* In 1924, Einthoven was awarded the [[Nobel Prize in Medicine]] for his pioneering work in developing the ECG.<ref name="Cooper_1986">{{Cite journal |last=Cooper JK |year=1986 |title=Electrocardiography 100 years ago. Origins, pioneers, and contributors |journal=N Engl J Med |volume=315 |issue=7 |pages=461\u201364 |doi=10.1056/NEJM198608143150721 |pmid=3526152}}</ref>\n* By 1927, General Electric had developed a portable apparatus that could produce electrocardiograms without the use of the string galvanometer. This device instead combined amplifier tubes similar to those used in a radio with an internal lamp and a moving mirror that directed the tracing of the electric pulses onto film.<ref>{{Cite journal |last=Blackford, John M., MD |date=1 May 1927 |title=Electrocardiography: A Short Talk Before the Staff of the Hospital |journal=Clinics of the Virginia Mason Hospital |volume=6 |issue=1 |pages=28\u201334}}</ref>\n* In 1937, [[Taro Takemi]] invented a new portable electrocardiograph machine.<ref>{{Cite news |url=https://www.hsph.harvard.edu/takemi/about-the-program/dr-taro-takemi/ |title=Dr. Taro Takemi |date=2012-08-27 |work=Takemi Program in International Health |access-date=2017-10-21 |language=en-US}}</ref>\n* In 1942, Emanuel Goldberger increases the voltage of Wilson's unipolar leads by 50% and creates the augmented limb leads aVR, aVL and aVF. When added to Einthoven's three limb leads and the six chest leads we arrive at the 12-lead electrocardiogram that is used today.<ref name="nicehist">{{Cite web |year=2009 |title=A (not so) brief history of electrocardiography. |url=https://ecglibrary.com/ecghist.html}}</ref>\n* In the late 1940s [[Rune Elmqvist]] invented an inkjet printer - thin jets of ink deflected by electrical potentials from the heart, with good frequency response and direct recording of ECG on paper - the device, called the Mingograf, was sold by Siemens Elema until the 1990s.<ref>{{cite web\n  | title = A (not so) brief history of electrocardiography\n  | publisher = ECG Library\n  | date = 2006-01-03\n  | url = http://www.ecglibrary.com/ecghist.html\n  | doi = \n  | accessdate = 2021-01-11\n  | archive-date = 2012-01-27\n  | archive-url = https://www.webcitation.org/650UBAj8Z?url=http://www.ecglibrary.com/ecghist.html\n  | url-status = live\n  }}</ref>\n\n The word is derived from the [[Greek language|Greek]] ''electro'', meaning related to electrical activity; ''kardia'', meaning heart; and ''graph'', meaning "to write".{{citation needed|date=March 2021}}"}},
{"article_title": "Vehicle audio", "pageid": "78427", "revid": "1058710250", "timestamp": "2021-12-05T03:48:19Z", "history_paths": [["Vehicle audio --- Introduction ---", "History"]], "categories": ["american inventions", "audio players", "in-car entertainment", "radio hobbies", "sound production technology", "automotive accessories", "automotive technologies"], "heading_tree": {"Vehicle audio --- Introduction ---": {"History": {"Radio": {}, "Physical media": {}}, "Active noise control and noise synthesis": {}, "Components and terms": {}, "Legality": {}, "Gallery": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Vehicle audio --- Introduction ---|History": "[[File:Een Philips Autoradio veraangenaamt den rit en houdt den geest frisch.jpg|thumb|upright|1937 Philips Auto Radio. Weighing 24 kg and taking 8 litres of space, it was floor mounted with a wired remote control to be fitted to the dashboard.]]\n\nIn 1904, well before commercially viable technology for mobile radio was in place, [[United States|American]] [[inventor]] and self-described "Father of Radio" [[Lee de Forest]] did some demonstration around a '''car radio''' at the 1904 [[Louisiana Purchase Exposition]] in [[St. Louis, Missouri|St. Louis]].<ref>{{cite web |last=Erb |first=Ernst |title=First Car radios-history and development of early Car Radios |url= https://www.radiomuseum.org/forum/first_car_radios_history_and_development_of_early_car_radios.html |website=radiomuseum.org |date=30 April 2012 |access-date=10 February 2020}}</ref>\n\nAround 1920, [[vacuum tube]] technology had matured to the point where the availability of [[radio receiver]]s made radio broadcasting viable.<ref>{{cite journal|last=Guarnieri|first=M.|year=2012|title=The age of vacuum tubes: the conquest of analog communications |journal=IEEE Ind. Electron. M. |pages=52\u201354 |doi=10.1109/MIE.2012.2193274 |s2cid=42357863}}</ref> A technical challenge was that the vacuum tubes in the radio receivers required 50 to 250 [[Voltage|volt]] [[direct current]], but car batteries ran at 6V. Voltage was stepped up with a [[Vibrator (electronic)|vibrator]] that provided a pulsating DC which could be converted to a higher voltage with a [[transformer]], [[Rectifier|rectified]], and filtered to create higher-voltage DC.\n\nIn 1924, Kelly's Motors in NSW, Australia, installed its first car radio.<ref>{{cite web|url= http://www.carhistory4u.com/the-last-100-years/parts-of-the-car/car-radio |title=Car History 4U - History of the Car Radio in Motor Cars |date=2012-12-09|access-date=2018-08-17|archive-url= https://web.archive.org/web/20121209064343/http://www.carhistory4u.com/the-last-100-years/parts-of-the-car/car-radio |archive-date=2012-12-09}}</ref><ref>{{cite web|url= https://www.radioinfo.com.au/news/lessons-history-inform-acma-thinking-today-radcomms-conference |title=Lessons of history inform ACMA thinking today: RadComms Conference|date=30 April 2009 |website=Radio info|access-date=17 August 2018}}</ref><ref>{{cite web|url= https://www.autoguru.com.au/car-advice/articles/10-aussie-auto-facts-you-probably-didnt-know |title=10 Aussie Auto Facts You Probably Didn't Know |website=autoguru.com.au |language=en |access-date=2018-08-17}}</ref>\n\nIn 1930, the American [[Galvin Manufacturing Corporation]] marketed a [[Motorola]] branded [[radio receiver]] for $130.<ref name="caranddriver">{{cite web|title=The History of Car Radios|url= http://www.caranddriver.com/features/the-history-of-car-radios |website=Car and Driver|date= 25 October 2010 |access-date=14 January 2016}}</ref> It was expensive: the contemporary [[Ford Model A (1927\u201331)|Ford Model A]] cost $540. A Plymouth sedan, "wired for Philco Transistone radio without extra cost," is advertised in [[Ladies' Home Journal]] in 1931. In 1932 in Germany the [[Blaupunkt]] AS 5 [[medium wave]] and [[longwave]] radio was marketed for 465 Reichsmark, about one third of the price of a small car. Because it took nearly 10 litres of space, it could not be located near the driver, and was operated via a steering wheel remote control.<ref>{{cite web|title=Blaupunkt: Success Story|url = http://www.blaupunkt.com/us/about-us/success-story/ |website=blaupunkt.com|access-date = 2016-01-14}}</ref> In 1933 [[Crossley Motors]] offer a factory fitted car radio.<ref name="guinness">{{cite book |last=Harding (ed) |title=Guinness book of car facts and feats |year=1977 |publisher=Guinness Superlatives|location=London |isbn=0-900424-54-0}}</ref> By the late 1930s, push button AM radios were considered a standard feature. In 1946, there were an estimated 9 million AM car radios in use.<ref name="When the car radio was introduced">{{Cite web|title = When the Car Radio Was Introduced, People Freaked Out |url = http://mentalfloss.com/article/29631/when-car-radio-was-introduced-people-freaked-out |website=MentalFloss |date = 3 January 2012 |access-date=2016-08-10}}</ref>\n\nAn [[Frequency modulation|FM]] receiver was offered by Blaupunkt in 1952. In 1953, Becker introduced the AM/FM Becker Mexico with a Variometer tuner, basically a station-search or scan function.<ref name="The History of the Car Stereo">{{cite web|title=The History of the Car Stereo |url= https://www.pcmag.com/article2/0,2817,2399878,00.asp |website= PCMAG |access-date=2016-01-14}}</ref>\n\nIn April 1955, the [[Chrysler|Chrysler Corporation]] announced that it was offering a [[Mopar]] model 914HR branded [[Philco]] all transistor car radio,<ref>{{Cite web|title = Mopar 914-HR Ch= C-5690HR Car Radio Philco, Philadelphia|url = http://www.radiomuseum.org/r/philco_mopar_914_hr_ch_c_5690hr.html |website= www.radiomuseum.org|access-date = 2016-01-14}}</ref> as a $150 option for its 1956 Chrysler and Imperial car models. Chrysler Corporation had decided to discontinue its all transistor car radio option at the end of 1956, due to it being too expensive, and replaced it with a cheaper hybrid (transistors and low voltage vacuum tubes) car radio for its new 1957 car models.<ref name="Hirsh">{{cite web|last = Hirsh|first = Rick|url= http://www.allpar.com/stereo/Philco/index.html |title= Philco's All-Transistor Mopar Car Radio|publisher = Allpar.com|access-date = February 18, 2015}}</ref> In 1963, Becker introduced the Monte Carlo, a tubeless [[Solid-state electronics|solid state]] radio with no vacuum tubes.<ref name="The History of the Car Stereo"/>\n\nFrom 1974 to 2005, the [[Autofahrer-Rundfunk-Informationssystem]] was used by the German [[ARD (broadcaster)|ARD]] network.<ref>{{cite web | title=Institut f\u00fcr Rundfunktechnik Historic Milestones |url=http://www.irt.de/en/irt/milestones.html |access-date=2009-05-17| archive-url= https://web.archive.org/web/20090420084023/http://www.irt.de/en/irt/milestones.html| archive-date= 20 April 2009 | url-status= live}}</ref> Developed jointly by the [[Institut f\u00fcr Rundfunktechnik]] and Blaupunkt,<ref>{{cite web|title=March 2009: RDS is now 25 \u2013 the complete history |url= http://www.rds.org.uk/rds98/pdf/RDS_25_090327_4.pdf |publisher=The RDS Forum |location=Geneva, Switzerland |date=2009-03-27 |page=1 |access-date=2009-05-17 |url-status=dead |archive-url= https://web.archive.org/web/20091007182550/http://www.rds.org.uk/rds98/pdf/RDS_25_090327_4.pdf |archive-date=October 7, 2009 }}</ref> it indicated the presence of traffic announcements through manipulation of the 57[[kHz]] [[subcarrier]] of the station's FM signal.<ref>{{Cite patent|EP|1432157}}</ref> ARI was replaced by the [[Radio Data System]].<ref>{{cite web |title=Das Autofahrer-Rundfunk-Informationssystem wird abgeschaltet |url= http://www.shortnews.de/start.cfm?id=562110 |publisher=ShortNews |location=Regensburg, Germany |date=2005-02-28 |language=de |access-date=2009-05-17}}</ref>\n\nIn the 2010s, [[internet radio]] and [[Satellite radio system|satellite radio]] came into competition with FM radio. By this time some models were offering [[5.1 surround sound]]. And the automobile head unit became increasingly important as a housing for front and [[backup camera|backup]] [[dashcam]]s, [[Automotive navigation system|navis]], and operating systems with multiple functions, such as [[Android Auto]], [[CarPlay]] and [[MirrorLink]]. Latest models are coming equipped with features like Bluetooth technology along with HDMI port for better connectivity. Screen size varies from 5-inch to 7-inch for the double Din car stereos.<ref>{{cite web|url= https://stereoauthority.com/best-double-din-stereo/ |title=Best Double Din Stereo 2019 - Top 5 Reviews|date=2019-01-01 |website=Stereo Authority |language=en-US |access-date=2019-01-16}}</ref>\n\nThe AM/FM radio combined with a CD player has remained a mainstay of car audio, despite being obsolescent in non-car applications.<ref>{{cite web|url= https://www.crutchfield.ca/learn/is-the-car-cd-player-dead.html |title=Is the car CD player dead?|first=Dominic |last=DeVito |work=Crutchfield}}</ref><ref>{{cite web|url= https://www.hagerty.com/articles-videos/Articles/2018/01/08/obsolete-car-audio-part-5 |title=History of obsolete car audio, part 5: What's old is new (or, at least, in vogue) |first=Rob|last=Siegel |website=hagerty.com|date=8 January 2018 }}</ref>\n\nMost modern vehicle audio are now equipped with [[anti-theft system]] for protection purposes.\n\n Mobile players for physical media have been provided for [[vinyl record]]s, [[8-track tape]]s, [[cassette tape]]s, and [[compact disc]]s.\n\nAttempts at providing mobile play from media were first made with vinyl records, beginning in the 1950s. The first such player was offered by Chrysler as an option on 1956 Chrysler, Desoto, Dodge, and Plymouth cars. The player was developed by [[CBS Labs]] and played a limited selection of specially provided 7-inch discs at 16\u2154 [[RPM]]. The unit was an expensive option and was dropped after two years. Cheaper options using commonly available [[45 rpm record]]s were made by [[RCA Victor]] (available only in 1961) and [[Norelco]]. All of these players required extra pressure on the [[Gramophone needle|needle]] to avoid skipping during vehicle movement, which caused accelerated wear on the records.<ref>{{cite web |url= https://www.consumerreports.org/cro/news/2014/04/record-players-were-the-infotainment-systems-of-the-1950s-and-60s/index.htm |title=Record players were the infotainment systems of the 1950s and '60s |author=Sharon Riley |date=April 12, 2014 |work=Consumer Reports |access-date=April 16, 2020}}</ref>\n\nIn 1962, Muntz introduced the Wayfarer 4-track cartridge tape player.  Celebrities, including Frank Sinatra, had these units installed in their cars.\n\nIn 1965, [[Ford Motor Company|Ford]] and Motorola jointly introduced the in-car [[8-track tape]] player as optional equipment for 1966 Ford car models. In 1968, a dashboard car radio with a built-in [[cassette tape]] player was introduced by Philips. In subsequent years, cassettes supplanted the 8-track and improved the technology, with longer play times, better tape quality, auto-reverse, and [[Dolby noise-reduction system|Dolby noise reduction]]. They were popular throughout the 1970s and 1980s.\n\nPioneer introduced the CDX-1, the first car [[CD]] (compact disc) player, in 1984. It was known for its improved sound quality, instant track skipping, and the format's increased durability over cassette tapes. Car CD changers started to gain popularity in the late 80s and continuing throughout the 90s, with the earlier devices being trunk-mounted and later ones being mounted in the head unit, some able to accommodate six to ten CDs.<ref>{{cite web|url= http://ca.complex.com/music/2015/02/the-evolution-of-playing-music-in-your-car/1980s-1990s-the-rise-of-the-cd |title=The Evolution of Playing Music in Your Car 1980s-1990s: The Rise of the CD |work=Complex CA |language=en|access-date=2017-01-22}}</ref> Stock and aftermarket CD players began appearing in the late 1980s, competing with the cassette. The first car with an OEM CD player was the 1987 [[Lincoln Town Car]], and the last new cars in the American market to be factory-equipped with a cassette deck in the dashboard was the 2010 Lexus SC430,<ref>{{cite news|title = For Car Cassette Decks, Play Time Is Over|url = https://www.nytimes.com/2011/02/06/automobiles/06AUDIO.html |newspaper=The New York Times |date=2011-02-04|access-date =2016-01-14 |first=Stephen |last=Williams}}</ref> and the Ford Crown Victoria.<ref>{{cite news|title=The in car cassette deck lives on for one more year |url= http://www.autoguide.com/auto-news/2011/03/the-in-car-cassette-deck-lives-on-for-one-more-year.html}}</ref> The car cassette adapter allowed motorists to plug in a portable music player (CD player, MP3 player) into an existing installed cassette tape deck.<ref>{{Cite web|url= https://www.vice.com/en_us/article/gyz9j7/the-car-cassette-adapter-was-an-unsung-hero-at-the-dawn-of-the-digital-age |title=The Car Cassette Adapter Was an Unsung Hero at the Dawn of the Digital Age |first=Ernie |last=Smith |date=November 6, 2019}}</ref>\n\nIn the early 21st century, compact digital storage media \u2013 [[Bluetooth]]-enabled devices, [[thumb drive]]s, [[memory cards]], and dedicated hard drives \u2013 came to be accommodated by vehicle audio systems."}},
{"article_title": "Paper shredder", "pageid": "79488", "revid": "1057490558", "timestamp": "2021-11-27T23:40:08Z", "history_paths": [["Paper shredder --- Introduction ---", "History of use"]], "categories": ["american inventions", "office equipment", "paper recycling", "records management technology", "security", "products introduced in 1935"], "heading_tree": {"Paper shredder --- Introduction ---": {"Invention": {}, "History of use": {}, "Types": {"Mobile shredding truck": {}, "Kiosks": {}, "Services": {}}, "Shredding method, and output": {"Security levels": {"''Deutsches Institut f\u00fcr Normung'' (DIN)": {}, "NSA/CSS": {}, "ISO/IEC": {}}}, "Destruction of evidence": {}, "Unshredding and forensics": {"Reconstruction examples": {}, "Forensic identification": {}}, "Recycling of waste": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Paper shredder --- Introduction ---|History of use": "Until the mid-1980s, it was rare for paper shredders to be used by non-government entities.\n\nA high-profile example of their use was when the [[Embassy of the United States, Tehran|U.S. embassy in Iran]] used shredders to reduce [[paper]] pages to strips before [[Iran hostage crisis|the embassy was taken over in 1979]], but some documents were reconstructed from the strips, as detailed below.\n\nAfter Colonel [[Oliver North]] told [[United States Congress|Congress]] that he used a Schleicher cross-cut model to shred [[Iran-Contra]] documents, sales for that company increased nearly 20 percent in 1987.<ref>{{cite magazine |url=http://content.time.com/time/magazine/article/0,9171,966794,00.html |title=Business notes office equipment |magazine=Time |date=1988-02-29 |access-date=2009-07-27 |url-status=live |archive-url=https://web.archive.org/web/20070930115604/http://www.time.com/time/magazine/article/0,9171,966794,00.html?promoid=googlep |archive-date=2007-09-30}}</ref>\n\nPaper shredders became more popular among U.S. citizens with [[privacy]] concerns after the 1988 [[Supreme Court of the United States|Supreme Court]] decision in ''[[California v. Greenwood]]''; in which the Supreme Court of the United States held that the [[Fourth Amendment to the United States Constitution|Fourth Amendment]] does not prohibit the warrantless search and seizure of garbage left for collection outside of a home. Anti-burning laws also resulted in increased demand for paper shredding.\n\nMore recently, concerns about [[identity theft]] have driven increased personal use,<ref>{{cite web|title=About Identity Theft|url=http://www.ftc.gov/bcp/edu/microsites/idtheft/consumers/about-identity-theft.html|work=US FTC website|url-status=dead|archive-url=https://web.archive.org/web/20090520060906/http://www.ftc.gov/bcp/edu/microsites/idtheft/consumers/about-identity-theft.html|archive-date=2009-05-20}}</ref> with the US Federal Trade Commission recommending that individuals shred financial documents before disposal.<ref>{{cite web|title=Fighting Back Against Identity Theft|url=http://www.ftc.gov/bcp/edu/pubs/consumer/idtheft/idt01.shtm|work=US FTC website|url-status=live|archive-url=https://web.archive.org/web/20090528001302/http://www.ftc.gov/bcp/edu/pubs/consumer/idtheft/idt01.shtm|archive-date=2009-05-28}}</ref>\n\n[[Information privacy]] laws such as [[Fair and Accurate Credit Transactions Act|FACTA]], [[Health Insurance Portability and Accountability Act|HIPAA]], and the [[Gramm\u2013Leach\u2013Bliley Act]] are driving shredder usage, as businesses and individuals take steps to securely dispose of confidential information."}},
{"article_title": "SCART", "pageid": "80765", "revid": "1054105433", "timestamp": "2021-11-08T02:52:31Z", "history_paths": [["SCART --- Introduction ---", "History"]], "categories": ["analog video connectors", "audiovisual connectors", "high-definition television", "film and video technology", "analog display connectors"], "heading_tree": {"SCART --- Introduction ---": {"History": {}, "Features": {"Daisy chaining": {}, "Direct connections": {}, "RGB overlays": {}, "Device control": {}}, "Design": {"Cables": {}, "Blanking and switching": {}, "Non-standard extensions": {}}, "Implementations": {}, "Japanese RGB 21-pin connector": {}, "Newer standards": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"SCART --- Introduction ---|History": "Before SCART was introduced, TVs did not offer a standardised way of inputting signals other than [[RF connector|RF]] antenna connectors, and these differed between countries. Assuming other connectors even existed, devices made by various companies could have different and incompatible standards. For example, a domestic VCR could output a [[composite video]] signal through a German-originated [[DIN plug|DIN-style connector]], an American-originated [[RCA connector]], an [[SO-239|SO239]] connector or a [[BNC connector]].\n\nThe SCART connector first appeared on TVs in 1977. It became compulsory on new TVs sold in France from January 1980,<ref>{{cite web|url=http://croque-vacances2.chez-alice.fr/tele801.htm|title=La t\u00e9l\u00e9 des ann\u00e9es 80|work=croque-vacances.com|url-status=dead|archive-url=https://web.archive.org/web/20090403222027/http://croque-vacances2.chez-alice.fr/tele801.htm|archive-date=April 3, 2009}} [https://translate.googleusercontent.com/translate_c?depth=1&nv=1&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=https://web.archive.org/web/20090403222027/http://croque-vacances2.chez-alice.fr/tele801.htm&usg=ALkJrhjLC8U77h_9qJsKeUny1sMgChOyZg Alt URL]</ref><ref>{{cite web|url=http://perso.orange.fr/fabrice.montupet/tipresse.htm|title=Le TI-99/4A et la Presse Informatique|work=perso.orange.fr/fabrice.montupet|url-status=dead|archive-url=https://web.archive.org/web/20071014174806/http://perso.orange.fr/fabrice.montupet/tipresse.htm|archive-date=October 14, 2007}} [https://translate.googleusercontent.com/translate_c?depth=1&nv=1&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=https://web.archive.org/web/20071014174806/http://perso.orange.fr/fabrice.montupet/tipresse.htm&usg=ALkJrhjUjLbC0Zo9mlNahQoXf1x5sIoi3Q Alt URL]</ref> and since 1989/1990 in eastern Europe, such as Poland. The actual French legal decree was adopted on 7 February 1980 and revoked on 3 July 2015.<ref>{{Cite web|url=https://translate.googleusercontent.com/translate_c?depth=1&nv=1&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=https://www.legifrance.gouv.fr/affichTexte.do%3Bjsessionid%3D72F30CF74F7243AE43E0FC5A8452E4E1.tpdila24v_1%3FcidTexte%3DJORFTEXT000030838473%26dateTexte%3D%26oldAction%3DrechJO%26categorieLien%3Did%26idJO%3DJORFCONT000030838080&usg=ALkJrhiapKQOl4WC8dgs6RQsiFG1trv-Eg|title=Arr\u00eat\u00e9 du 3 juillet 2015 abrogeant l'arr\u00eat\u00e9 du 7 f\u00e9vrier 1980 portant homologation et mise en application obligatoire de la norme fran\u00e7aise NF C 92-250|publisher=Legifrance}}</ref>\n\nThe standard was subject to several amendments and at least 2 major revisions, approved by CENELEC on 13 November 1988 (EN 50049-1:1989) and 1 July 1997 (EN 50049-1:1997).<ref name="British Standard">{{cite book|url=http://fr.meric.free.fr/Articles/articlesba/stsurtvplat/Scart/BS_EN_50049-1%20Peritelevision%20connector.pdf|title=Domestic and similar electronic equipment interconnection requirements: Peritelevision connector|date=15 June 1998|publisher=[[British Standards Institution]]|isbn=0580298604}}</ref>"}},
{"article_title": "Windows Metafile", "pageid": "81673", "revid": "1028477686", "timestamp": "2021-06-14T06:41:19Z", "history_paths": [["Windows Metafile --- Introduction ---", "History"]], "categories": ["graphics file formats", "vector graphics", "microsoft windows multimedia technology"], "heading_tree": {"Windows Metafile --- Introduction ---": {"History": {}, "Metafile structure": {"WMF": {"Bitmap records": {}, "Drawing records": {}, "Object records": {}, "State records": {}, "Escape records": {}}, "EMF": {}, "EMF+": {}}, "Implementations": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Windows Metafile --- Introduction ---|History": "The original 16 bit WMF file format was fully specified in volume 4 of the 1992 Windows 3.1 SDK documentation<ref>Microsoft Windows 3.1 Programmers Reference, Volume 4 Resources, Microsoft Press 1992, {{ISBN|1-55615-494-1}}, chapter 3 pp. 21-45</ref> (at least if combined with the descriptions of the individual functions and structures in the other volumes), but that specification was vague about a few details. These manuals were published as printed books available in bookstores with no [[clickwrap|click through]] [[End-user license agreement|EULA]] or other unusual licensing restrictions (just a general warning that if purchased as part of a software bundle, the software would be subject to one).\n\nOver time the existence of that historic specification was largely forgotten and some alternative implementations resorted to reverse engineering to figure out the file format from existing WMF files, which was difficult and error prone.<ref>{{cite web | url=http://wvware.sourceforge.net/caolan/support.html | title=Window Metafile (wmf) Reference | quote=''These opcodes are unimplemented, for the reason that i dont know what they are, no known documentation'' | author=Caolan McNamara | access-date=2008-06-01}}</ref> In September 2006, Microsoft again published the WMF file format specification in a more complete form<ref>{{cite web | url=http://msdn.microsoft.com/en-us/library/cc215212.aspx | title=<nowiki>[MS-WMF]:</nowiki> Windows Metafile Format Specification | access-date=2008-06-01 }}</ref> in the context of the [[Microsoft Open Specification Promise]], promising to not assert patent rights to file format implementors.<ref name="osp">{{cite web | url=http://www.microsoft.com/interop/osp/ | title=Microsoft Open Specification Promise | access-date=2008-06-01 }}</ref>\n\nMicrosoft later deprecated WMF files in favour of 32-bit EMF files as WMF files had real issues with device independence, despite the use of a "placeable" file header which provided basic device independence. Microsoft found that developers who use the format were "[embedding] application, location, or scaling comments in the metafiles... Others added headers to the metafile that provided various application-specific information", causing major compatibility issues.<ref name="ENHMETA_technote">{{citation|title=Enhanced Metafiles in Win32|publisher=Microsoft Developer Network Technology Group|date=June 10, 1993|url=http://www.massmind.org/techref/fileext/emf/enh_meta.htm}}</ref> Thus, in 1992 with [[Windows NT 3.1]], Microsoft introduced the Enhanced Metafile format (EMF)<ref name="rfc7903">{{cite IETF|title = Windows Image Media Types|rfc = 7903|sectionname = Windows Metafiles|page = 1|last1 = Leonard|first1 = Sean|date = September 2016|publisher = [[Internet Engineering Task Force|IETF]]|access-date = February 8, 2020|issn = 2070-1721|doi = 10.17487/RFC7903}}</ref> — a format which was based on the [[Win32]] API and with which they built-in in device independence.<ref name="emfintroduced">{{citation|url=https://wiki.fileformat.com/image/emf/|title=EMF|work=FileFormat|publisher=Aspose Pty Ltd|access-date=2020-01-20}}</ref><ref name="ENHMETA_technote"/> — these were also known as NT metafiles.<ref>{{citation|title=NT Metafiles and GDI Objects|first=Charles|last=Petzold|author-link=Charles Petzold|work=[[PC Magazine]]|date=October 11, 1994|pages=343\u2013347|url=https://books.google.com/books?id=fy_G-xlQbE8C&pg=PA345}}</ref> With the release of Windows XP and GDI+, the set of records had to be significantly increased and so Microsoft released EMF+ as an extension to the existing EMF file format.<ref name="rfc7903"/><ref>{{cite book|title=Graphics Programming with GDI+ & DirectX|publisher=A-List Publishing|page=68|year=2005|first1=Alex|last1=Polyakov|first2=Vitaly|last2=Brusentsev|isbn=1-931769-39-7|url=https://books.google.com/books?id=MJ_VAwAAQBAJ&pg=PA68}}</ref>"}},
{"article_title": "Blender (software)", "pageid": "81926", "revid": "1063140775", "timestamp": "2022-01-01T13:30:23Z", "history_paths": [["Blender (software) --- Introduction ---", "History"], ["Blender (software) --- Introduction ---", "Release history"]], "categories": ["1995 software", "3d animation software", "3d graphics software", "3d computer graphics software for linux", "3d rendering software for linux", "amigaos 4 software", "articles containing video clips", "blender foundation", "computer science in the netherlands", "computer-aided design software for linux", "cross-platform free software", "formerly proprietary software", "free 3d graphics software", "free computer-aided design software", "free software programmed in c", "free software programmed in c++", "free software programmed in python", "global illumination software", "information technology in the netherlands", "visual effects software", "irix software", "macos graphics-related software", "morphos software", "motion graphics software for linux", "portable software", "software that uses ffmpeg", "technical communication tools", "video game development software", "windows graphics-related software", "2d animation software"], "heading_tree": {"Blender (software) --- Introduction ---": {"History": {}, "Suzanne": {}, "Release history": {}, "Features": {"Modeling": {"Primitives": {}, "Modifiers": {}, "Sculpting": {}, "Geometry Nodes": {}, "Hard surface modeling": {}}, "Simulation": {"Fluid simulation": {}}, "Animation": {"Grease Pencil": {}}, "Rendering": {"Texture and shading": {}}, "Post-production": {}, "Plugins/addons and scripts": {}, "Deprecated features": {}, "Blender Internal": {}, "File format": {"Import and export": {}}}, "User interface": {"Commands": {}, "Modes": {}, "Workspaces": {}}, "Rendering engines": {"Cycles": {"GPU rendering": {}, "Integrator": {"The two types of integrators": {}}, "Open Shading Language": {}, "Materials": {"Surface shader": {}, "Volume shader": {}, "Displacement shader": {}}}, "EEVEE": {}, "Workbench": {}, "External renderers": {}, "Past renderers": {"Blender Internal": {}, "Blender Game Engine": {}}}, "Development": {"Blender 2.8": {}, "Cycles X": {}}, "Support": {}, "Modified versions": {}, "Use in industry": {}, "Open projects": {"''Elephants Dream'' (Project Orange)": {}, "''Big Buck Bunny'' (Project Peach)": {}, "''Yo Frankie!'' (Open ''Game'' Project: Apricot)": {}, "''Sintel'' (Project Durian)": {}, "''Tears of Steel'' (Project Mango)": {}, "''Cosmos Laundromat: First Cycle'' (Project Gooseberry)": {}, "''Glass Half''": {}, "''Caminandes''": {}, "''Agent 327: Operation Barbershop''": {}, "''Hero''": {}, "''Spring''": {}, "''Coffee Run''": {}, "''Sprite Fright''": {}}, "Online services": {"Blender Foundation": {"Blender Studio": {}, "The Blender Development Fund": {}, "Blender ID": {}, "Blender Open Data": {}, "Blender Network": {}, "Blender Store": {}}, "Blender Community": {"BlenderArtists": {}, "Blender Market": {}}}, "Notes": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Blender (software) --- Introduction ---|History": "[[File:Blender-Desktop-2-77.png|250px|thumb|right|Models and render in version 2.77 (2016)]]\n[[File:Blender Editor.jpg|250px|thumb|right|A Blender [[Cube]] (Version 2.93).]]\n\nThe [[Netherlands|Dutch]] animation studio NeoGeo (not associated with the [[Neo Geo]] video game hardware entity) started to develop Blender as an in-house application, and based on the [[timestamp]]s for the first [[source code|source files]], January 2, 1994 is considered to be Blender's birthday.<ref>{{cite web |url=https://code.blender.org/2013/12/how-blender-started-twenty-years-ago/ |title=How Blender started, twenty years ago\u2026 |website=Blender Developers Blog |publisher=Blender Foundation |language=en |access-date=2019-01-10}}</ref> The version 1.00 was released in January 1995,<ref>{{cite web|url=https://archive.blender.org/wiki/index.php/Doc:DK/2.6/Manual|title=Doc:DK/2.6/Manual - BlenderWiki|work=Blender.org|access-date=2019-01-11}}</ref> with the primary author being company co-owner and software developer [[Ton Roosendaal]]. The name ''Blender'' was inspired by a song by the Swiss electronic band [[Yello]], from the album ''[[Baby (Yello album)|Baby]]'' which NeoGeo used in its [[showreel]].<ref>{{Cite web|date=2021-10-19|title=Ton Roosendaal Reveals the Origin of Blender\u2019s name|url=https://www.blendernation.com/2021/10/19/ton-roosendaal-reveals-the-origin-of-blenders-name/|access-date=2021-10-20|website=BlenderNation|language=en-US}}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/3CdA_NMw7lc Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20190216080628/https://www.youtube.com/watch?v=3CdA_NMw7lc&gl=US&hl=en Wayback Machine]{{cbignore}}: {{cite web|url=https://www.youtube.com/watch?v=3CdA_NMw7lc |title=NeoGeo \u2014 Blender |publisher=YouTube.com |date=2011-10-28 |access-date=2019-06-11}}{{cbignore}}</ref><ref>{{cite web |url=http://www.mopi.nl/blogo/p1.html |title=Brief history of the Blender logo \u2014 Traces |last=Kassenaar |first=Joeri |date=2006-07-20 |access-date=2010-01-22 |archive-url=https://web.archive.org/web/20100122234804/http://www.mopi.nl/blogo/p1.html |archive-date=2010-01-22 |url-status=unfit}}</ref> Some of the design choices and experiences for Blender were carried over from an earlier software application, called Traces, that Roosendaal developed for NeoGeo on the Commodore Amiga platform during the 1987\u20131991 period.<ref>{{Cite web|url=http://zgodzinski.com/blender-prehistory/|title=Blender's prehistory - Traces on Commodore Amiga (1987-1991)|website=zgodzinski.com}}</ref>\n\nOn January 1, 1998, Blender was released publicly online as [[Silicon Graphics|SGI]] freeware.<ref name="25th" /> NeoGeo was later dissolved and its client contracts were taken over by another company. After NeoGeo's dissolution, Ton Roosendaal founded Not a Number Technologies (NaN) in June 1998 to further develop Blender, initially distributing it as [[shareware]]<!--did the c-key make it shareware?--> until NaN went bankrupt in 2002. This also meant, at the time, discontinuing the development of Blender.<ref>{{cite web |url=https://www.blender.org/foundation/history/ |title=Blender History|website=Blender.org |access-date=March 29, 2018}}</ref>\n\nIn May 2002, Roosendaal started the non-profit [[Blender Foundation]], with the first goal to find a way to continue developing and promoting Blender as a community-based [[Open-source software|open-source]] project. On July 18, 2002, Roosendaal started the ''"Free Blender"'' campaign, a [[crowdfunding]] precursor.<ref>{{cite web|url=http://www.linuxtoday.com/infrastructure/2002072201226OSBZCY |title=Blender Foundation Launches Campaign to Open Blender Source |publisher=Linux Today |access-date=2017-01-22}}</ref><ref>{{cite web|url=http://www.blender3d.com/campaign.html|archive-url=https://web.archive.org/web/20021010045558/http://www.blender3d.com/campaign.html |url-status=dead |archive-date=2002-10-10 |title=Free Blender campaign |date=2002-10-10 |access-date=2017-01-22}}</ref> The campaign aimed at open-sourcing Blender for a one-time payment of \u20ac100,000 (US$100,670 at the time), with the money being collected from the community.<ref>{{cite web|url=http://www.blender3d.com/members.html|archive-url=https://web.archive.org/web/20021010174347/http://www.blender3d.com/members.html |url-status=dead |archive-date=2002-10-10 |title=members |date=2002-10-10 |access-date=2017-01-22}}</ref> On September 7, 2002, it was announced that they had collected enough funds and would release the Blender [[source code]]. Today, Blender is [[free and open-source software]], largely developed by its community as well as 24 employees employed by the Blender Institute.<ref name=":13">{{cite web |url=https://www.blender.org/institute/ |title=Blender.org About |location=Amsterdam |access-date=2021-02-01}}</ref>\n\nThe Blender Foundation initially reserved the right to use [[dual license|dual licensing]], so that, in addition to [[GNU General Public License|GPL-2.0-or-later]], Blender would have been available also under the ''Blender License'' that did not require disclosing source code but required payments to the Blender Foundation. However, they never exercised this option and suspended it indefinitely in 2005.<ref>{{cite web |url=https://www.blender.org/BL/ |title=Blender License |access-date=January 19, 2007 |last=Roosendaal |first=Ton |date=June 2005 |archive-url=https://web.archive.org/web/20160304090101/https://www.blender.org/BL/ |archive-date=March 4, 2016 |url-status=dead }}</ref> Blender is solely available under "GNU GPLv2 or any later" and was not updated to the [[GPLv3]], as "no evident benefits" were seen.<ref name="libredwg-gplv3-opinion">{{cite web |url=http://libregraphicsworld.org/blog/entry/whats-up-with-dwg-adoption-in-free-software |title=What's up with DWG adoption in free software? |last=Prokoudine |first=Alexandre |date=26 January 2012 |access-date=2015-12-05 |publisher=libregraphicsworld.org |quote=''[Blender's Ton Roosendaal:] "Blender is also still "GPLv2 or later". For the time being we stick to that, moving to GPL 3 has no evident benefits I know of. My advice for LibreDWG: if you make a library, choosing a widely compatible license (MIT, BSD, or LGPL) is a very positive choice."'' |url-status=dead |archive-url=https://web.archive.org/web/20161109103037/http://libregraphicsworld.org/blog/entry/whats-up-with-dwg-adoption-in-free-software |archive-date=9 November 2016 }}</ref>\n\nIn 2019, with the release of version 2.80, the integrated [[Blender Game Engine|game engine]] for making and prototyping video games was removed; Blender's developers recommended users migrate to more powerful [[open source]] game engines such as [[Godot (game engine)|Godot]] instead.<ref name="bge-removed">{{cite web|title=rB159806140fd3|url=https://developer.blender.org/rB159806140fd33e6ddab951c0f6f180cfbf927d38|website=developer.blender.org|access-date=2019-02-28}}</ref><ref name="OSgodotRec">{{cite web|title=Blender 2.80 release|url=https://www.blender.org/download/releases/2-80/|website=blender.org|access-date=2020-01-16}}</ref>", "Blender (software) --- Introduction ---|Release history": "The following table lists notable developments during Blender's release history: green indicates the current version (3.0.0), yellow indicates currently supported versions, and red indicates versions that are no longer supported (though many later versions can still be used on modern systems).{{Citation needed|date=May 2020}}\n\n{| class="wikitable collapsible"\n|+\n! Version\n! scope="col" style="width: 9.5em;" | Release Date<ref>{{cite web |url=http://download.blender.org/source/ |title=Index of /source/ |website=blender.org |access-date=October 13, 2010}}</ref>\n! Notes and key changes\n|-\n| {{Version|o|1.00}}\n| January 1994\n| Blender in development.<ref name="Foundation">{{Cite web|url=https://docs.blender.org/manual/en/latest/getting_started/about/history.html|title=Blender's History|first=Blender|last=Foundation}}</ref>\n|-\n| {{Version|o|1.23}}\n| January 1998\n| SGI version released, [[IrisGL]].<ref name="Foundation"/>\n|-\n| {{Version|o|1.30}}\n| April 1998\n| Linux and FreeBSD version, port to OpenGL and [[X11]].<ref name="Foundation"/>\n|-\n| {{Version|o|1.4x}}\n| September 1998\n| [[Solaris (operating system)|Sun]] and Linux [[DEC Alpha|Alpha]] version released.<ref name="Foundation"/>\n|-\n| {{Version|o|1.50}}\n| November 1998\n| First Manual published.<ref name="Foundation"/>\n|-\n| {{Version|o|1.60}}\n| April 1999\n| New features behind a $95 lock. Windows version released.<ref name="Foundation"/>\n|-\n| {{Version|o|1.6x}}\n| June 1999\n| [[BeOS]] and PPC version released.<ref name="Foundation"/>\n|-\n| {{Version|o|1.80}}\n| June 2000\n| Blender freeware again.<ref name="Foundation"/>\n|-\n| {{Version|o|2.00}}\n| August 2000\n| Interactive 3D and real-time engine.<ref name="Foundation"/>\n|-\n| {{Version|o|2.03}}\n| 2000\n| Handbook ''The official Blender 2.0 guide''.\n|-\n| {{Version|o|2.10}}\n| December 2000\n| New engine, physics, and Python.<ref name="Foundation"/>\n|-\n| {{Version|o|2.20}}\n| August 2001\n| Character animation system.<ref name="Foundation"/>\n|-\n| {{Version|o|2.21}}\n| October 2001\n| Blender Publisher launch.<ref name="Foundation"/>\n|-\n| {{Version|o|2.2x}}\n| December 2001\n| Apple macOS version.<ref name="Foundation"/>\n|-\n| {{Version|o|2.25}}\n| October 13, 2002\n| Blender Publisher freely available.<ref name="Foundation"/>\n|-\n| {{Version|o|2.26}}\n| February 2003\n| The first truly open source Blender release.<ref name="Foundation"/>\n|-\n| {{Version|o|2.30}}\n| November 22, 2003\n| New [[GUI]]; edits are now reversible.\n|-\n| {{Version|o|2.32}}\n| February 3, 2004\n| [[Ray tracing (graphics)|Ray tracing]] in internal renderer; support for [[YafaRay]].\n|-\n| {{Version|o|2.34}}\n| August 5, 2004\n| LSCM-UV-Unwrapping, object-particle interaction.\n|-\n| {{Version|o|2.37}}\n| May 31, 2005\n| Simulation of elastic surfaces; improved subdivision surface.\n|-\n| {{Version|o|2.40}}\n| December 22, 2005\n| Greatly improved system and character animations (with a non-linear editing tool), and added a fluid and hair simulator. New functionality was based on ''[[Google Summer of Code]]'' 2005.<ref>{{cite web|url=http://www.blender.org/development/release-logs/blender-240/ |title=Blender 2.40 |website=blender.org |access-date=December 23, 2005 |url-status=dead |archive-url=https://web.archive.org/web/20070304080023/http://www.blender.org/development/release-logs/blender-240/ |archive-date=March 4, 2007 }}</ref>\n|-\n| {{Version|o|2.41}}\n| January 25, 2006\n| Improvements of the game engine (programmable vertex and pixel shaders, using Blender materials, split-screen mode, improvements to the physics engine), improved UV mapping, recording of the [[Python (programming language)|Python]] scripts for sculpture or sculpture works with the help of grid or mesh (mesh sculpting) and set-chaining models.\n|-\n| {{Version|o|2.42}}\n| July 14, 2006\n| The film ''[[Elephants Dream]]'' resulted in high development as a necessity. In particular, the [[Node graph architecture|Node-System]] (Material- and Compositor) has been implemented.\n|-\n| {{Version|o|2.43}}\n| February 16, 2007\n| ''Sculpt-Modeling'' as a result of ''[[Google Summer of Code]] 2006''.\n|-\n| {{Version|o|2.46}}\n| May 19, 2008\n| With the production of ''Big Buck Bunny'', Blender gained the ability to produce grass quickly and efficiently.<ref>{{cite web |url=http://www.heise.de/newsticker/meldung/108160 |title=3D-Software Blender 2.46 zum Download freigegeben |website=heise.de |language=de |access-date=May 20, 2008}}</ref>\n|-\n| {{Version|o|2.48}}\n| October 14, 2008\n| Due to development of ''[[Yo Frankie!]]'', the game engine was improved substantially.<ref>{{cite web|url=http://www.blender.org/development/release-logs/blender-248/ |title=Blender 2.48 |website=blender.org |access-date=December 25, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20090120083347/http://www.blender.org/development/release-logs/blender-248 |archive-date=January 20, 2009 }}</ref>\n|-\n| {{Version|o|2.49}}\n| June 13, 2009\n| New window and file manager, new interface, new [[Python (programming language)|Python]] API, and new animation system.<ref>{{cite web|url=http://www.blender.org/development/release-logs/blender-249/ |title=Blender 2.49 |website=blender.org |access-date=June 21, 2009 |url-status=dead |archive-url=https://web.archive.org/web/20090611183623/http://www.blender.org/development/release-logs/blender-249/ |archive-date=June 11, 2009 }}</ref>\n|-\n| {{Version|o|2.57}}\n| April 13, 2011\n| First official stable release of 2.5 branch: new interface, new window manager and rewritten event \u2014 and tool \u2014 file processing system, new animation system (each setting can be animated now), and new Python API.<ref>{{cite web |url=http://www.blender.org/development/release-logs/blender-257/ |title=Blender 2.57 |website=blender.org |access-date=April 13, 2011 |archive-url=https://web.archive.org/web/20131030043004/http://www.blender.org/development/release-logs/blender-257/ |archive-date=October 30, 2013}}</ref>\n|-\n| {{Version|o|2.58}}\n| June 22, 2011\n| New features, such as the addition of the warp modifier and render baking. Improvements in sculpting.<ref>{{cite web | url = https://archive.blender.org/wiki/index.php/Dev:Ref/Release_Notes/2.58 | title = Blender 2.58 release notes | access-date = 2019-01-14 | author = blenderfoundation | date = 2011-07-09 | publisher = blender.org}}</ref>\n|-\n| {{Version|o|2.58a}}\n| July 4, 2011\n| Some bug fixes, along with small extensions in GUI and [[Python (programming language)|Python]] interface.<ref>{{cite web | url = https://archive.blender.org/wiki/index.php/Dev:Ref/Release_Notes/2.58/Bug_Fixes/2.58a | title = Blender 2.58a update log | access-date = 2019-01-14 | author = blenderfoundation | date = 2011-07-09 | publisher = blender.org}}</ref>\n|-\n| {{Version|o|2.59}}\n| August 13, 2011\n| 3D mouse support.\n|-\n| {{Version|o|2.60}}\n| October 19, 2011\n| Developer branches integrated into the main developer branch: among other things, B-mesh, a new rendering/shading system, [[Non-uniform rational B-spline|NURBS]], to name a few, directly from [[Google Summer of Code]].\n|-\n| {{Version|o|2.61}}\n| December 14, 2011\n| New Render Engine, Cycles, added alongside Blender Internal (as a "preview release").<ref>{{Cite web|title=Dev:Ref/Release Notes/2.61 - BlenderWiki|url=https://archive.blender.org/wiki/index.php/Dev:Ref/Release_Notes/2.61/|access-date=2020-11-26|website=archive.blender.org}}</ref> [[Motion capture|Motion Tracking]], Dynamic Paint, and Ocean Simulator.\n|-\n| {{Version|o|2.62}}\n| February 16, 2012\n| Motion tracking improvement, further expansion of UV tools, and remesh modifier. Cycles render engine updates to make it more production-ready.\n|-\n| {{Version|o|2.63}}\n| April 27, 2012\n| Bug fixes, B-mesh project: completely new mesh system with n-corners, plus new tools: dissolve, inset, bridge, vertex slide, vertex connect, and bevel.\n|-\n| {{Version|o|2.64}}\n| October 3, 2012\n| [[Chroma key|Green screen]] keying, node-based compositing.\n|-\n| {{Version|o|2.65}}\n| December 10, 2012\n| Over 200 bug fixes, support for the [[Open Shading Language]], and fire simulation.\n|-\n| {{Version|o|2.66}}\n| February 21, 2013\n| Rigid body simulation available outside of the game engine, dynamic topology sculpting, hair rendering now supported in Cycles.\n|-\n| {{Version|o|2.67}}\n| May 7\u201330, 2013\n| Freestyle rendering mode for non-photographic rendering, [[subsurface scattering]] support added, the motion tracking solver is made more accurate and faster, and an add-on for 3D printing now comes bundled.\n|-\n| {{Version|o|2.68}}\n| July 18, 2013\n| Rendering performance is improved for [[CPU]]s and GPUs, support for [[NVIDIA]] Tesla K20, GTX Titan and GTX 780 GPUs. Smoke rendering improved to reduce blockiness.<ref>{{cite web|url=https://archive.blender.org/wiki/index.php/Dev:Ref/Release_Notes/2.68|title=Dev:Ref/Release Notes/2.68 - BlenderWiki|website=blender.org|access-date=2019-01-14}}</ref>\n|-\n| {{Version|o|2.69}}\n| October 31, 2013\n| Motion tracking now supports plane tracking, and hair rendering has been improved.\n|-\n| {{Version|o|2.70}}\n| March 19, 2014\n| Initial support for [[volume rendering]] and small improvements to the user interface.\n|-\n| {{Version|o|2.71}}\n| June 26, 2014\n| Support for baking in Cycles and volume rendering branched path tracing now renders faster.\n|-\n| {{Version|o|2.72}}\n| October 4, 2014\n| Volume rendering for GPUs, more features for sculpting and painting.\n|-\n| {{Version|o|2.73}}\n| January 8, 2015\n| New fullscreen mode, improved Pie Menus, 3D View can now display the world background.<ref name="past-releases">{{cite web |url=http://www.blender.org/features/past-releases/ |title=Past Releases |website=blender.org |access-date=November 13, 2015}}</ref>\n|-\n| {{Version|o|2.74}}\n| March 31, 2015\n| Cycles got several precision, noise, speed, memory improvements, and a new Pointiness attribute.<ref name="past-releases" />\n|-\n| {{Version|o|2.75a}}\n| July 1, 2015\n| Blender now supports a fully integrated Multi-View and Stereo 3D pipeline, Cycles has much-awaited initial support for AMD GPUs, and a new Light Portals feature.<ref name="past-releases" />\n|-\n| {{Version|o|2.76b}}\n| November 3, 2015\n| Cycles volume density render, [[Pixar]] OpenSubdiv mesh subdivision library, node inserting, and video editing tools.<ref name="past-releases" />\n|-\n| {{Version|o|2.77a}}\n| April 6, 2016\n| Improvements to Cycles, new features for the Grease Pencil, more support for OpenVDB, updated [[Python (programming language)|Python]] library and support for Windows XP has been removed.<ref>{{cite web |url=https://www.blender.org/features/2-77/ |title=Blender 2.77|publisher=blender.org |date=March 19, 2016 |access-date=March 29, 2016}}</ref>\n|-\n| {{Version|o|2.78c}}\n| February 28, 2017\n| Spherical stereo rendering for virtual reality, Grease Pencil improvements for 2D animations, Freehand curves drawing over surfaces, Bendy Bones, Micropolygon displacements, and Adaptive Subdivision. Cycles performance improvements.<ref>{{cite web |url=https://www.blender.org/features/2-78/ |title=Blender 2.78b Release Logs|publisher=blender.org |date=February 16, 2017 |access-date=September 30, 2016}}</ref>\n|-\n| {{Version|o|2.79b}}\n| September 11, 2017\n| Cycles denoiser, improved OpenCL rendering support, Shadow Catcher, Principled BSDF Shader, Filmic color management, improved UI and Grease Pencil functionality, improvements in Alembic import and export, surface deformities modifier, better animation keyframing, simplified video encoding, [[Python (programming language)|Python]] additions and new add-ons.<ref>{{Cite web|url=https://wiki.blender.org/wiki/Dev:Ref/Release_Notes/2.79|title=Reference/Release Notes/2.79 - Blender Developer Wiki|website=wiki.blender.org}}</ref>\n|-\n| {{Version|o|2.80}}\n| July 30, 2019\n| Revamped UI, added a dark theme,<ref>{{Cite web|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.80/UI|title=Reference/Release Notes/2.80/UI - Blender Developer Wiki|date=26 June 2019|website=Blender Developer Wiki|access-date=11 July 2019}}</ref> EEVEE realtime rendering engine on OpenGL, Principled shader,<ref>{{Cite web|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.80/EEVEE|title=Reference/Release Notes/2.80/EEVEE - Blender Developer Wiki|date=9 July 2019|website=Blender Developer Wiki|access-date=11 July 2019}},</ref> Workbench viewport<ref name="auto">{{cite web|url=https://twitter.com/tonroosendaal/status/991709311293448192|title=Ton Roosendaal on Twitter|website=Twitter|access-date=May 24, 2018}}</ref> Grease Pencil 2D animation tool,<ref>{{Cite web|url=https://code.blender.org/2017/12/drawing-2d-animation-in-blender-2-8/|title=Drawing 2D Animation in Blender 2.8 - Blender Developers Blog|date=12 December 2017|website=Blender Developers Blog - Developer musings on Blender|access-date=11 July 2019}}</ref> multi-object editing, collections, GPU+CPU rendering, Rigify.<ref>{{Cite web|url=https://www.blender.org/download/releases/2-80/|title=2.80 - Blender.org|date=11 July 2019|website=blender.org - Home of the Blender project - Free and Open 3D Creation Software|access-date=11 July 2019}}</ref>\n|-\n| {{Version|o|2.81a}}\n| November 21, 2019\n| OpenVDB voxel remesh, QuadriFlow remesh, transparent BSDF, brush curves preset in sculpting, [[WebM]] support.<ref>{{Cite web|url=https://www.blender.org/download/releases/2-81/|title=2.81 blender.org|date=18 August 2019|access-date=19 August 2019}}</ref>\n|-\n| {{Version|o|2.82}}\n|February 14, 2020\n| Improved fluid and smoke simulation (using Mantaflow), [https://docs.blender.org/manual/en/2.82/modeling/meshes/editing/uv/workflows/udims.html UDIM] support, [[Universal Scene Description|USD]] export<ref>{{Cite web|url=https://www.blender.org/download/releases/2-82/|title=2.82|access-date=15 February 2020}}</ref> and 2 new sculpting tools.\n|-\n| {{Version|co|2.83{{break}}LTS}}\n|June 3, 2020<ref>{{Cite web|last=Foundation|first=Blender|title=2.83 LTS|url=https://www.blender.org/download/releases/2-83/|access-date=2020-06-10|website=blender.org|language=en}}</ref>\n| Improved performance and user interface with the grease pencil tool, added VR capability, hair simulation uses same physics as cloth simulation, cloth self-collision has been optimized with 15-20% performance increase, bug fixes and usability improvements for fluid systems, new cloth brush added, new clay thumb brush, layer brush was redesigned, voxel remesh can be previewed, voxel mode added for remesh modifier, multiresolution rewritten to resolve artifacts, adaptive sampling for cycles, EEVEE supports more passes to make it more viable for final renders. (This LTS version is now being maintained until 2022.) Actual state is 2.83.18 in October 2021 with about 300 bugfixes in comparison to initial 2.83.0. Cuda 11 support for last Nvidia Series with Ampere and OptiX support for Maxwell+ are included in last patches.<ref>{{Cite web|url=https://www.blender.org/download/lts/|title = Long-term Support}}</ref>\n|-\n| {{Version|o|2.90}}\n|August 31, 2020<ref>{{Cite web|last=Foundation|first=Blender|title=2.90|url=https://www.blender.org/download/releases/2-90/|access-date=2021-10-02|website=blender.org|language=en}}</ref><ref>{{Cite web|title=What's new in Blender 2.90?|url=https://cgcookie.com/articles/everything-new-in-blender-2-90|access-date=2021-10-02|website=CG Cookie|language=en}}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/7M1UaDe0qsk Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20200831232158/https://www.youtube.com/watch?v=7M1UaDe0qsk&list=WL&index=10 Wayback Machine]{{cbignore}}: {{Citation|title=Blender 2.90 New Features in LESS than 5 minutes|url=https://www.youtube.com/watch?v=7M1UaDe0qsk|language=en|access-date=2021-10-02}}{{cbignore}}</ref>\n| Built-in Nishita realistic sky texturing,<ref>{{Cite web|title=Sky Texture Node \u2014 Blender Manual|url=https://docs.blender.org/manual/en/2.90/render/shader_nodes/textures/sky.html|access-date=2021-10-02|website=docs.blender.org|language=en}}</ref><ref>{{Cite web|last=Scratchapixel|title=Simulating the Colors of the Sky|url=https://www.scratchapixel.com//lessons/procedural-generation-virtual-worlds/simulating-sky|access-date=2021-10-02|website=Scratchapixel}}</ref> completely rewritten EEVEE motion blur,<ref>{{Cite web|title=rBf84414d6e14c|url=https://developer.blender.org/rBf84414d6e14c|access-date=2021-10-02|website=developer.blender.org}}</ref> viewport denoising with OpenImageDenoise,<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/wWudE_gamCk Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20200626225418/https://www.youtube.com/watch?v=wWudE_gamCk Wayback Machine]{{cbignore}}: {{Citation|title=Blender Denoising Just Got CRAZIER With OPENIMAGEDENOISE|url=https://www.youtube.com/watch?v=wWudE_gamCk|language=en|access-date=2021-10-02}}{{cbignore}}</ref><ref>{{Citation|title=CPU DENOISE IN THE VIEWPORT! {{!}} Blender Today|url=https://www.youtube.com/watch?v=czULfXW81sU|language=en|access-date=2021-10-02}}</ref> new shadow terminator offset which fixes some shading artifacts,<ref>{{Cite web|title=Object \u2014 Blender Manual|url=https://docs.blender.org/manual/en/2.90/render/cycles/object_settings/object_data.html#shading|access-date=2021-10-02|website=docs.blender.org}}</ref> the Multires Modifier can now rebuild lower subdivisions levels and extract its displacement,<ref>{{Cite web|title=Multiresolution Modifier \u2014 Blender Manual|url=https://docs.blender.org/manual/en/2.90/modeling/modifiers/generate/multiresolution.html|access-date=2021-10-02|website=docs.blender.org}}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/DCFVn_EjBXA Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20211002115052/https://www.youtube.com/watch?v=DCFVn_EjBXA Wayback Machine]{{cbignore}}: {{Citation|title=BLENDER 2.9 Alpha - MULTIREZ IS HERE WITH UPDATES! \ud83d\ude0d|url=https://www.youtube.com/watch?v=DCFVn_EjBXA|language=en|access-date=2021-10-02}}{{cbignore}}</ref><ref>{{Cite web|title=Reference/Release Notes/2.90/Sculpt - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.90/Sculpt|access-date=2021-10-02|website=wiki.blender.org}}</ref> new scale/translate and squash & stretch pose brushes,<ref>{{Cite web|title=rB77789a190491|url=https://developer.blender.org/rB77789a19049|access-date=2021-10-02|website=developer.blender.org}}</ref><ref>{{Cite web|title=rB3778f168f688|url=https://developer.blender.org/rB3778f168f68|access-date=2021-10-02|website=developer.blender.org}}</ref><ref>{{Cite web|title=rB438bd823714a|url=https://developer.blender.org/rB438bd823714|access-date=2021-10-02|website=developer.blender.org}}</ref> extrude manifold tool removes adjacent faces when extruding inwards,<ref>{{Cite web|title=rBb79a5bdd5ae0|url=https://developer.blender.org/rBb79a5bdd5ae0|access-date=2021-10-02|website=developer.blender.org}}</ref><ref name=":6">{{Cite web|title=Reference/Release Notes/2.90/Modeling - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.90/Modeling|access-date=2021-10-02|website=wiki.blender.org}}</ref> bevel custom profile now supports bezier curve handle types,<ref>{{Cite web|title=rBbaff05ad1c15|url=https://developer.blender.org/rBbaff05ad1c15|access-date=2021-10-02|website=developer.blender.org}}</ref> spray direction maps in ocean modifier,<ref>{{Cite web|title=rB17b89f6dacba|url=https://developer.blender.org/rB17b89f6dacba|access-date=2021-10-02|website=developer.blender.org}}</ref><ref name=":6" /> automatic UV adjustment when editing mesh,<ref>{{Cite web|title=rB4387aff99e01|url=https://developer.blender.org/rB4387aff|access-date=2021-10-02|website=developer.blender.org}}</ref> updated search UI showing the location for menu items,<ref>{{Cite web|title=Reference/Release Notes/2.90/User Interface - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.90/User_Interface|access-date=2021-10-02|website=wiki.blender.org}}</ref> UI improvements like feature headings and more readable checkbox layouts,<ref>{{Cite web|title=rB219049bb3b76|url=https://developer.blender.org/rB219049bb3b76|access-date=2021-10-02|website=developer.blender.org}}</ref> reordering the modifier stack,<ref>{{Cite web|title=rB9b099c86123f|url=https://developer.blender.org/rB9b099c86123f|access-date=2021-10-02|website=developer.blender.org}}</ref> and more stats display options.<ref>{{Cite web|title=rBfd10ac9acaa0|url=https://developer.blender.org/rBfd10ac9acaa0|access-date=2021-10-02|website=developer.blender.org}}</ref>\n|-\n| {{Version|o|2.91}}\n|November 25, 2020<ref name=":1">{{Cite web|title=2.91|url=https://www.blender.org/download/releases/2-91/|access-date=2020-11-26|website=blender.org|language=en}}</ref>\n|New more advanced exact [[Constructive solid geometry|boolean]] solver for more accurate cuts.<ref>{{Cite web|title=Reference/Release Notes/2.91/Modeling - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/Modeling|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB9e09b5c418c0|url=https://developer.blender.org/rB9e09b5c418c0|access-date=2021-10-20|website=developer.blender.org}}</ref>Curves objects now can have a custom bevel profile.<ref>{{Cite web|title=rB60fa80de0b2c|url=https://developer.blender.org/rB60fa80de0b2c|access-date=2021-10-20|website=developer.blender.org}}</ref> Cloth brush improvements with support for collisions<ref>{{Cite web|title=Reference/Release Notes/2.91/Sculpt - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/Sculpt|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB675700d94892|url=https://developer.blender.org/rB675700d9489|access-date=2021-10-20|website=developer.blender.org}}</ref> and posing.<ref>{{Cite web|title=rBc2f0522760b2|url=https://developer.blender.org/rBc2f0522760b|access-date=2021-10-20|website=developer.blender.org}}</ref> New boundry brush<ref>{{Cite web|title=rBed9c0464bae6|url=https://developer.blender.org/rBed9c0464bae|access-date=2021-10-20|website=developer.blender.org}}</ref> and trimming tools.<ref>{{Cite web|title=rB675c9644420e|url=https://developer.blender.org/rB675c9644420|access-date=2021-10-20|website=developer.blender.org}}</ref> New Volume modifers for converting mesh to volume,<ref>{{Cite web|title=Reference/Release Notes/2.91/Volumes - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/Volumes|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB5845c06a63a6|url=https://developer.blender.org/rB5845c06a63a6|access-date=2021-10-20|website=developer.blender.org}}</ref> Volume to mesh<ref>{{Cite web|title=rBf7832b1583cd|url=https://developer.blender.org/rBf7832b1583cd|access-date=2021-10-20|website=developer.blender.org}}</ref> and Volume displace.<ref>{{Cite web|title=rB1f50beb9f28e|url=https://developer.blender.org/rB1f50beb9f28edd|access-date=2021-10-20|website=developer.blender.org}}</ref>  New compound shapes for rigid body physics simulations.<ref>{{Cite web|title=Reference/Release Notes/2.91/Physics - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/Physics|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB820ca419e098|url=https://developer.blender.org/rB820ca419e098|access-date=2021-10-20|website=developer.blender.org}}</ref> Improved animation F-curves to be more snappier.<ref>{{Cite web|title=Reference/Release Notes/2.91/Animation-Rigging - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/Animation-Rigging|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rBda95d1d851b4|url=https://developer.blender.org/rBda95d1d851b|access-date=2021-10-20|website=developer.blender.org}}</ref> The properties editor now has a search tool for searching for settings.<ref>{{Cite web|title=Reference/Release Notes/2.91/User Interface - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/User_Interface|access-date=2021-10-20|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB7c633686e995|url=https://developer.blender.org/rB7c633686e995|access-date=2021-10-20|website=developer.blender.org}}</ref><ref>{{Cite web|title=rB8bcdcab659fb|url=https://developer.blender.org/rB8bcdcab659fb|access-date=2021-10-20|website=developer.blender.org}}</ref><ref>{{Cite web|title=rBbedbd8655ed1|url=https://developer.blender.org/rBbedbd8655ed1|access-date=2021-10-20|website=developer.blender.org}}</ref> Search results now improved due to fuzzy search implimentation.<ref>{{Cite web|title=rB98eb89be5dd0|url=https://developer.blender.org/rB98eb89be5dd08f3|access-date=2021-10-20|website=developer.blender.org}}</ref> Library Overide improvements.<ref>{{Cite web|title=Reference/Release Notes/2.91/IO - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.91/IO|access-date=2021-10-20|website=wiki.blender.org}}</ref>\n|-\n| {{Version|o|2.92}}\n|February 25, 2021<ref>{{Cite web|last=Foundation|first=Blender|title=2.92|url=https://www.blender.org/download/releases/2-92/|access-date=2021-02-27|website=blender.org|language=en}}</ref>\n|A new modifier for more advanced [[Procedural modeling|procedural modelling]] called Geometry Nodes which connects to a custom node editor.<ref>{{Cite web|title=Reference/Release Notes/2.92/Geometry Nodes - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Geometry_Nodes|access-date=2021-11-04|website=wiki.blender.org}}</ref> Main functionality is with procedural scattering. New about dialog<ref>{{Cite web|title=rB79eeabafb39f|url=https://developer.blender.org/rB79eeabafb39f|access-date=2021-11-04|website=developer.blender.org}}</ref> and other UI tweaks and changes.<ref>{{Cite web|title=Reference/Release Notes/2.92/User Interface - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/User_Interface|access-date=2021-11-04|website=wiki.blender.org}}</ref> A new tool for creating primitive objects interactively<ref name=":16">{{Cite web|title=Reference/Release Notes/2.92/Modeling - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Modeling|access-date=2021-11-04|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB122cb1aea823|url=https://developer.blender.org/rB122cb1a|access-date=2021-11-04|website=developer.blender.org}}</ref> and a new copy modifier operator.<ref name=":16" /> A new sculpt brush that's manipulates the geometry based on the silhouette.<ref>{{Cite web|title=Reference/Release Notes/2.92/Sculpt - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Sculpt|access-date=2021-11-04|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB383c20a6abd6|url=https://developer.blender.org/rB383c20a6abd|access-date=2021-11-04|website=developer.blender.org}}</ref> EEVEE support for AOV<ref>{{Cite web|title=Reference/Release Notes/2.92/EEVEE - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/EEVEE|access-date=2021-11-04|website=wiki.blender.org}}</ref> and cryptomatte passes. Mantalfow [[Fluid animation|fluid simulations]] now support APIC.<ref>{{Cite web|title=Reference/Release Notes/2.92/Physics - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Physics|access-date=2021-11-04|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB8bdf191461a6|url=https://developer.blender.org/rB8bdf191461a6|access-date=2021-11-04|website=developer.blender.org}}</ref> Colliders can now be disabled with a toggle button.<ref>{{Cite web|title=rBac290bfbe434|url=https://developer.blender.org/rBac290bfbe|access-date=2021-11-04|website=developer.blender.org}}</ref> Bone Constraints now have a custom space option<ref>{{Cite web|title=Reference/Release Notes/2.92/Animation-Rigging - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Animation-Rigging|access-date=2021-11-04|website=wiki.blender.org}}</ref> NLA strip can now sync length based on the position of the key-frames.<ref>{{Cite web|title=rB60746363875a|url=https://developer.blender.org/rB60746363875a67ae15278d8e4629f898d9562c47|access-date=2021-11-04|website=developer.blender.org}}</ref> New exposure node for the compositor.<ref>{{Cite web|title=Reference/Release Notes/2.92/More Features - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/More_Features|access-date=2021-11-04|website=wiki.blender.org}}</ref><ref>{{Cite web|title=rB6538f1e600ad|url=https://developer.blender.org/rB6538f1e600ad|access-date=2021-11-04|website=developer.blender.org}}</ref>\n|-\n| {{Version|co|2.93{{break}}LTS}}\n| June 2, 2021<ref>{{Cite web|last=Foundation|first=Blender|title=2.93 LTS|url=https://www.blender.org/download/releases/2-93/|access-date=2021-10-14|website=blender.org|language=en}}</ref><ref name=":10">{{Cite web|title=Reference/Release Notes/2.93 - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93|access-date=2021-10-14|website=wiki.blender.org}}</ref>\n| Expansion of Geometry Nodes Attributes and Nodes including such as Mesh [[Geometric primitive|Primitives]]. A new [[spreadsheet]] editor for viewing attributes.<ref>{{Cite web|title=Reference/Release Notes/2.93/Geometry Nodes - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/Geometry_Nodes|access-date=2021-10-14|website=wiki.blender.org}}</ref> Sculpting improvements.<ref>{{Cite web|title=Reference/Release Notes/2.93/Sculpt - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/Sculpt|access-date=2021-10-14|website=wiki.blender.org}}</ref> Grease Pencil Line Art modifier, interpolate tool, fill tool improvements. Import and export grease pencils as [[Scalable Vector Graphics|SVGs]] and [[PDF|PDFs]].<ref>{{Cite web|title=Reference/Release Notes/2.93/Grease Pencil - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/Grease_Pencil|access-date=2021-10-14|website=wiki.blender.org}}</ref> EEVEE improvements with volumetrics, ambient occlusion and depth of field.<ref>{{Cite web|title=Reference/Release Notes/2.93/EEVEE - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/EEVEE|access-date=2021-10-14|website=wiki.blender.org}}</ref> Cycles persistent data and support for Intel Open Image Denoise version 1.3.<ref>{{Cite web|title=Reference/Release Notes/2.93/Cycles - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/Cycles|access-date=2021-10-14|website=wiki.blender.org}}</ref> Python 3.9 support.<ref>{{Cite web|title=Reference/Release Notes/2.93/Python API - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/2.93/Python_API|access-date=2021-10-14|website=wiki.blender.org}}</ref> This LTS version is scheduled to be maintained until 2023. [[Windows 7]] is no longer supported. Windows 8.1 or newer is required.<ref name=":10" /> Actual Version is 2.93.7 (December 2021).\n|-\n| {{Version|c|3.0}}\n| December 3, 2021<ref>{{Cite web|title=BF Blender (3.0)|url=https://developer.blender.org/project/view/120/|access-date=2021-11-10|website=developer.blender.org}}</ref><ref>{{Cite web|last=Foundation|first=Blender|title=Call for videos, \u201cBLENDER IS\u2026\u201d|url=https://www.blender.org/news/call-for-videos-blender-is/|access-date=2021-11-10|website=blender.org|language=en}}</ref>\n|New Asset Browser editor with Pose library.<ref>{{Cite web|last=Foundation|first=Blender|title=Asset Browser Project Update|url=https://code.blender.org/2021/06/asset-browser-project-update/|access-date=2021-07-02|website=Blender Developers Blog|language=en}}</ref><ref>{{Cite web|date=2021-07-16|title=Pose Library v2.0 now in master!|url=https://www.blendernation.com/2021/07/16/pose-library-v2-0-now-in-master/|access-date=2021-08-11|website=BlenderNation|language=en-US}}</ref><ref>{{Cite web|last=Foundation|first=Blender|title=Pose Library v2.0|url=https://code.blender.org/2021/05/pose-library-v2-0/|access-date=2021-08-11|website=Blender Developers Blog|language=en}}</ref> [[Universal Scene Description|USD]] importer.<ref>{{Cite web|date=2021-08-07|title=Blender 3.0 gets USD Import!|url=https://www.blendernation.com/2021/08/07/blender-3-0-gets-usd-import/|access-date=2021-08-11|website=BlenderNation|language=en-US}}</ref> Geometry Nodes Curve support<ref>{{Cite web|date=2021-08-10|title=Blender 3.0 Gets Two New Curve Editing Nodes|url=https://www.blendernation.com/2021/08/10/blender-3-0-gets-two-new-curve-editing-nodes/|access-date=2021-08-11|website=BlenderNation|language=en-US}}</ref><ref>{{Cite web|date=2021-06-02|title=Blender Developers Meeting Notes: May 31, 2021|url=https://www.blendernation.com/2021/06/02/blender-developers-meeting-notes-may-31-2021/|access-date=2021-08-11|website=BlenderNation|language=en-US}}</ref><ref name=":7">{{Cite web|last=Foundation|first=Blender|title=Procedural Curves in 3.0 and Beyond|url=https://code.blender.org/2021/09/procedural-curves-in-3-0-and-beyond/|access-date=2021-09-27|website=Blender Developers Blog|language=en}}</ref> and new fields system which makes geometry nodes more like working with shaders.<ref name=":8">{{Cite web|last=Foundation|first=Blender|title=Attributes and Fields|url=https://code.blender.org/2021/08/attributes-and-fields/|access-date=2021-10-02|website=Blender Developers Blog|language=en}}</ref><ref>{{Cite web|date=2021-08-18|title=Attributes and Fields: The Future of Geometry Nodes has Been Decided|url=https://www.blendernation.com/2021/08/18/attributes-and-fields-the-future-of-geometry-nodes-has-been-decided/|access-date=2021-10-02|website=BlenderNation|language=en-US}}</ref> Compressor Change from Gzip to faster zStandard in Core.<ref>{{Cite web|url=https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Core|title = Reference/Release Notes/3.0/Core - Blender Developer Wiki}}</ref> A new posterize node for the compositor.<ref>{{Cite web|date=2021-09-10|title=Blender Compositor Gets New Posterize Node|url=https://www.blendernation.com/2021/09/10/blender-compositor-gets-new-posterize-node/|access-date=2021-09-23|website=BlenderNation|language=en-US}}</ref> Dash to Dot grease pencil modifier.<ref>{{Cite web|date=2021-09-16|title=Grease Pencil New "Dot-Dash" Modifier|url=https://www.blendernation.com/2021/09/16/grease-pencil-new-dot-dash-modifier/|access-date=2021-09-23|website=BlenderNation|language=en-US}}</ref> Spreadsheet editor improvements.<ref>{{Cite web|date=2021-07-03|title=Spreadsheet Editor Gets Filtering Feature|url=https://www.blendernation.com/2021/07/03/spreadsheet-editor-gets-filtering-feature/|access-date=2021-09-23|website=BlenderNation|language=en-US}}</ref> Merging of the Cycles X branch giving performance improvements.<ref name=":2">{{Cite web|last=Foundation|first=Blender|title=Cycles X|url=https://code.blender.org/2021/04/cycles-x/|access-date=2021-05-01|website=Blender Developers Blog|language=en}}</ref><ref name=":3">{{Cite web|date=2021-09-21|title=Cycles X now in Blender 3.0 alpha!|url=https://www.blendernation.com/2021/09/21/cycles-x-now-in-blender-3-0-alpha/|access-date=2021-09-23|website=BlenderNation|language=en-US}}</ref><ref name=":4">{{Cite web|date=2021-04-23|title=Blender Announces Cycles X: The Blazingly Fast Future of Cycles|url=https://www.blendernation.com/2021/04/23/blender-announces-cycles-x-the-blazingly-fast-future-of-cycles/|access-date=2021-05-01|website=BlenderNation|language=en-US}}</ref> Removal of branched path tracing and [[OpenCL]] rendering.<ref name=":11">{{Cite web|title=Reference/Release Notes/3.0/Cycles - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles|access-date=2021-10-20|website=wiki.blender.org}}</ref>  Cycles HIP support for [[Advanced Micro Devices|AMD]] graphics cards.<ref name=":17">{{Cite web|last=Foundation|first=Blender|title=Next level support for AMD GPUs|url=https://code.blender.org/2021/11/next-level-support-for-amd-gpus/|access-date=2021-11-15|website=Blender Developers Blog|language=en}}</ref> The auto tile size add-on was also removed as the same functionality was natively implemented.<ref>{{Cite web|title=rBA20cbcd98e045|url=https://developer.blender.org/rBA20cbcd98e0455a0afdf8c69d7864f0721c49bca0|access-date=2021-10-20|website=developer.blender.org}}</ref> Open Image Denoise has been updated to version 1.4.<ref name=":11" /> EEVEE support for the wavelength node and the attribute node.<ref>{{Cite web|title=Reference/Release Notes/3.0/EEVEE - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/EEVEE|access-date=2021-10-31|website=wiki.blender.org}}</ref> The VR inspection add-on now supports controller visualisation and navigation functionality such as teleporting, flying and grabbing.<ref>{{Cite web|title=Reference/Release Notes/3.0/Virtual Reality - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Virtual_Reality|access-date=2021-11-05|website=wiki.blender.org}}</ref> Video Sequence editor Thumbnails,<ref>{{Cite web|title=rB997b5fe45dab|url=https://developer.blender.org/rB997b5fe45dab8bd0e2976c8b673e56266134fc80|access-date=2021-09-27|website=developer.blender.org}}</ref><ref name=":5">{{Citation|title=BLENDER ANEW {{!}} Blender.Today LIVE #171|url=https://www.youtube.com/watch?v=JSREL5GBbas|language=en|access-date=2021-09-27}}</ref> Transform tools<ref>{{Cite web|title=rBfa2c1698b077|url=https://developer.blender.org/rBfa2c1698b077f510175e79adf3dbf3e1602b1030|access-date=2021-09-27|website=developer.blender.org}}</ref><ref name=":5" /> and an increase of strip limit from 32 to 128.<ref>{{Cite web|title=rB8fecc2a85254|url=https://developer.blender.org/rB8fecc2a8525467ee2fbbaae16ddbbc10b3050d46|access-date=2021-09-27|website=developer.blender.org}}</ref><ref name=":5" /><ref>{{Cite web|date=2021-09-23|title=GSoC 2021 Roundup Part 2: UV Editor and VSE|url=https://www.blendernation.com/2021/09/23/gsoc-2021-roundup-part-2-uv-editor-and-vse/|access-date=2021-09-27|website=BlenderNation|language=en-US}}</ref>Knife tool improvements from the Google Summer of Code.<ref>{{Cite web|title=\u2699 D12600 GSOC 2021 Knife Tool Improvements Project|url=https://developer.blender.org/D12600|access-date=2021-09-27|website=developer.blender.org}}</ref><ref name=":5" /><ref>{{Cite web|last=Foundation|first=Blender|title=GSoC Roundup Episode Three: Ahead of the Curve, On the Cutting Edge|url=https://code.blender.org/2021/09/gsoc-roundup-episode-three-ahead-of-the-curve-on-the-cutting-edge/|access-date=2021-10-02|website=Blender Developers Blog|language=en}}</ref>Modelling performance improvements.<ref>{{Cite web|last=Foundation|first=Blender|title=Mesh Editing Optimization \u2013 Initial Steps|url=https://code.blender.org/2021/05/mesh-editing-optimization-initial-steps/|access-date=2021-10-02|website=Blender Developers Blog|language=en}}</ref> A new design for Panels<ref>{{Cite web|title=\u2699 D12814 UI: Visual style update to panels|url=https://developer.blender.org/D12814|access-date=2021-10-18|website=developer.blender.org}}</ref> and Nodes,<ref>{{Cite web|title=\u2699 D12884 Node Editor: Style update to nodes|url=https://developer.blender.org/D12884|access-date=2021-10-27|website=developer.blender.org}}</ref> Node Editor overlays for noodle colours and annotations,<ref>{{Cite web|title=\u2699 D12886 Node Editor: Introduce color overlay and dashed wires theme setting|url=https://developer.blender.org/D12886|access-date=2021-10-21|website=developer.blender.org}}</ref><ref>{{Cite web|date=2021-10-24|title=Node Editor UI Update: Colored Noodles and Customizability|url=https://www.blendernation.com/2021/10/24/node-editor-ui-update-colored-noodles-and-customizability/|access-date=2021-10-25|website=BlenderNation|language=en-US}}</ref> node editors now have a dot grid,<ref>{{Cite web|title=\u2699 D10345 Node Redesign: Dot Grid|url=https://developer.blender.org/D10345|access-date=2021-10-27|website=developer.blender.org}}</ref> Theme changes<ref>{{Cite web|title=rBbfec984cf82a|url=https://developer.blender.org/rBbfec984cf82a64a74ee86a902348a46e3c231b8f|access-date=2021-10-27|website=developer.blender.org}}</ref> and other UI tweaks.<ref>{{Cite web|title=Reference/Release Notes/3.0/User Interface - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/User_Interface|access-date=2021-10-18|website=wiki.blender.org}}</ref> Blenderkit add-on was removed as Blender ended support for commercial add-ons.<ref>{{Cite web|title=rBA13ecbb8fee64|url=https://developer.blender.org/rBA13ecbb8fee64fe3c262c6f904a2bd21ea2ca2070|access-date=2021-11-24|website=developer.blender.org}}</ref><ref>{{Cite web|title=Process/Addons - Blender Developer Wiki|url=https://wiki.blender.org/wiki/Process/Addons|access-date=2021-11-24|website=wiki.blender.org}}</ref>\n|-\n| {{Version|p|3.1}}\n| March 9, 2022<ref>{{Cite web|title=BF Blender (3.1)|url=https://developer.blender.org/project/view/135/|access-date=2021-11-03|website=developer.blender.org}}</ref><ref>{{Cite web|last=Felinto|first=Dalai|date=November 2, 2021|title=[Bf-committers] Blender 3.1 Preliminary Dates|url=https://lists.blender.org/pipermail/bf-committers/2021-November/051186.html|access-date=2021-11-03}}</ref>\n|Cycles [[Metal (API)|Metal]] Support.<ref>{{Cite web|date=2021-12-13|title=Cycles Apple Metal device feedback|url=https://devtalk.blender.org/t/cycles-apple-metal-device-feedback/21868|access-date=2021-12-13|website=Blender Developer Talk|language=en}}</ref><ref>{{Cite web|last=Dinges|first=Thomas|date=13 December 2021|title=[Bf-committers] Blender developer week notes - 2021.12.13|url=https://lists.blender.org/pipermail/bf-committers/2021-December/051219.html|url-status=live|access-date=13 December 2021}}</ref> AMD HIP support for Linux(unconfirmed for 3.1).<ref name=":17" /> Point Cloud Geometry type rendering support.<ref>{{Cite web|title=\u2699 D9887 Cycles: pointcloud geometry type|url=https://developer.blender.org/D9887|access-date=2021-12-20|website=developer.blender.org}}</ref> Panoramic cameras now support the Fisheye Lens Polynomial camera model.<ref>{{Cite web|title=rB24e016546302|url=https://developer.blender.org/rB24e01654630|access-date=2021-12-28|website=developer.blender.org}}</ref><ref name=":18">{{Cite web|date=2021-12-06|title=13 December 2021|url=https://devtalk.blender.org/t/13-december-2021/21738|access-date=2021-12-28|website=Blender Developer Talk|language=en}}</ref> Improved caustic rendering(unconfirmed for 3.1).<ref>{{Cite web|title=\u2699 D13533 Adding Manifold Next Event Estimation Sampling Technique|url=https://developer.blender.org/D13533|access-date=2021-12-21|website=developer.blender.org}}</ref><ref>{{Cite web|date=2021-12-20|title=Cycles To Get Fast Refractive Caustics|url=https://www.blendernation.com/2021/12/20/cycles-to-get-fast-refractive-caustics/|access-date=2021-12-21|website=BlenderNation|language=en-US}}</ref>Add node search menu now can be triggered by dragging a noodle in empty space.<ref>{{Cite web|title=rB11be151d58ec|url=https://developer.blender.org/rB11be151d58e|access-date=2021-12-28|website=developer.blender.org}}</ref> Geometry Nodes now has a execution time overlay,<ref>{{Cite web|title=rBe4986f92f32b|url=https://developer.blender.org/rBe4986f92f32|access-date=2021-12-01|website=developer.blender.org}}</ref> new nodes to access mesh topology<ref name=":18" />, a new dual mesh node<ref>{{Cite web|title=rBd54a08c8af12|url=https://developer.blender.org/rBd54a08c8af1|access-date=2021-12-28|website=developer.blender.org}}</ref> and a new accumulate field node<ref>{{Cite web|title=rBa836ded9902d|url=https://developer.blender.org/rBa836ded9902d67359ea94a03c45de7edd4f826fb|access-date=2021-12-30|website=developer.blender.org}}</ref>. A new shrink wrap modifier for grease pencil.<ref>{{Cite web|title=rB459af75d1ed5|url=https://developer.blender.org/rB459af75d1ed5|access-date=2021-12-14|website=developer.blender.org}}</ref> \nAlpha Version available since 27 October 2021<ref name=":15">{{cite web|last=Felinto|first=Dalai|date=October 27, 2021|title=[Bf-committers] Now at 3.0 Bcon3 (and 3.1 Bcon1)|url=https://lists.blender.org/pipermail/bf-committers/2021-October/051184.html|access-date=2021-10-27}}</ref>\n|-\n| colspan="3" | {{Version|l|show=111111}}\n|}\n\nAs of 2021, official releases of Blender for [[Microsoft Windows]], {{nowrap|[[MacOS]]}} and [[Linux]],<ref name="download">{{cite web|title=Download \u2013 blender.org \u2013 Home of the Blender project \u2013 Free and Open 3D Creation Software|url=https://www.blender.org/download/|publisher=[[Blender Foundation]]|access-date=July 30, 2014}}</ref> as well as a [[Porting|port]] for [[FreeBSD]],<ref>{{cite web|title=FreeBSD Ports: Graphics|url=https://www.freebsd.org/ports/graphics.html#blender-2.79_6|date=March 16, 2018|website=FreeBSD|publisher=The FreeBSD Project|access-date=March 16, 2018|archive-date=September 20, 2020|archive-url=https://web.archive.org/web/20200920053907/https://www.freebsd.org/ports/graphics.html#blender-2.79_6|url-status=dead}}</ref> are available in [[64-bit computing|64-bit]] versions. Blender is available for Windows 8.1 and above, and Mac OS X 10.13 and above.<ref>{{Cite web|url=https://www.blender.org/download/requirements/|title = Requirements}}</ref>\n\nBlender 2.76b was the last supported release for Windows XP and version 2.63 was the last supported release for [[PowerPC]]. Blender 2.83 LTS and 2.92 were the last supported versions for Windows 7.<ref name="system-requirements">{{cite web|title=System Requirements|url=https://www.blender.org/download/requirements/|website=Blender.org|access-date=March 29, 2016}}</ref> In 2013, Blender was released on [[Android (operating system)|Android]] as a demo but hasn't been updated since.<ref name="Index of /demo/android">{{Cite web|title=Index of /demo/android/|url=https://download.blender.org/demo/android/|access-date=2020-09-23|website=download.blender.org}}</ref>"}},
{"article_title": "Companion planting", "pageid": "81945", "revid": "1041386777", "timestamp": "2021-08-30T07:38:26Z", "history_paths": [["Companion planting --- Introduction ---", "History"]], "categories": ["sustainable gardening", "permaculture", "crops", "biological pest control", "sustainable technologies", "chemical ecology"], "heading_tree": {"Companion planting --- Introduction ---": {"History": {}, "Mechanisms": {"Provision of nutrients": {}, "Trap cropping": {}, "Host-finding disruption": {}, "Pest suppression": {}, "Predator recruitment": {}, "Protective shelter": {}}, "Systems": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Companion planting --- Introduction ---|History": "In China, [[Azolla|mosquito ferns]] (''Azolla'' spp.) have been used for at least a thousand years as companion plants for [[rice]] crops. They host a [[Cyanobacteria|cyanobacterium]] that fixes nitrogen from the atmosphere, and they block light from plants that would compete with the rice.<ref>{{cite web|url=http://www.dhakai.com/botany/Keynote%20paper.pdf|title=Plant Resources for Human Development-Nitrogen in Rice|publisher=Dhakai.com|access-date=February 21, 2015|url-status=dead|archive-url=https://web.archive.org/web/20160304231916/http://www.dhakai.com/botany/Keynote%20paper.pdf|archive-date=March 4, 2016}}</ref>\n\nCompanion planting was practiced in various forms by the [[indigenous peoples of the Americas]] prior to the arrival of Europeans. These peoples domesticated [[Cucurbita pepo|squash]] 8,000 to 10,000 years ago,<ref name="smith">Smith, B. D. (1997). [http://fbae.org/2009/FBAE/website/images/PDF%20files/Imporatant%20Publication/1997%20Squash%20origin.pdf The initial domestication of ''Cucurbita pepo'' in the Americas 10,000 years ago.] ''Science'' 276 932-34.</ref><ref name="ucla">{{cite web|url=http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/Cucurbita/|title=Cucurbitaceae--Fruits for Peons, Pilgrims, and Pharaohs|publisher=University of California at Los Angeles|access-date=September 2, 2013|url-status=dead|archive-url=https://web.archive.org/web/20131016003715/http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/Cucurbita/|archive-date=October 16, 2013}}</ref> then [[maize]], then [[Phaseolus vulgaris|common bean]]s, forming the [[Three Sisters (agriculture)|Three Sisters]] agricultural technique. The cornstalk served as a [[trellis (architecture)|trellis]] for the beans to climb, the beans [[Nitrogen fixation|fixed nitrogen]], benefitting the maize, and the wide leaves of the squash plant provide ample shade for the soil keeping it moist and fertile.<ref name="Mount Pleasant 2006">{{cite book |author-link=Jane Mount Pleasant |last=Mount Pleasant |first=Jane |editor1=Staller, John E. |editor2=Tykot, Robert H. |editor3=Benz, Bruce F. |title=Histories of Maize: Multidisciplinary Approaches to the Prehistory, Linguistics, Biogeography, Domestication, and Evolution of Maize |publisher=Academic Press |location=Amsterdam |year=2006 |pages=529\u2013537 |isbn=978-1-5987-4496-5 |chapter=The science behind the Three Sisters mound system: An agronomic assessment of an indigenous agricultural system in the northeast}}</ref><ref name="Landon">{{cite journal |last=Landon |first=Amanda J. |title=The 'How' of the Three Sisters: The Origins of Agriculture in Mesoamerica and the Human Niche |journal=Nebraska Anthropologist |year=2008 |url=https://digitalcommons.unl.edu/nebanthro/40/ |volume=23 |issn=1555-4937 |pages=110\u2013124}}</ref><ref name="Bushnell">{{cite journal |last=Bushnell |first=G. H. S. |title=The Beginning and Growth of Agriculture in Mexico |journal=Philosophical Transactions of the Royal Society of London |year=1976 |volume=275 |issue=936 |pages=117\u2013120 |doi=10.1098/rstb.1976.0074}}</ref>\n\nCompanion planting was widely promoted in the 1970s as part of the [[Organic horticulture|organic gardening]] movement.<ref>{{cite web |title=Companion Planting Guide |url=https://wheelbarrowexpert.com/companion-planting-guide/ |website=Mel's Garden |access-date=12 July 2018|date=2018-07-11 }}</ref> It was encouraged for pragmatic reasons, such as natural [[Trellis (architecture)|trellising]], but mainly with the idea that [[List of companion plants|different species of plant]] may thrive more when close together.<ref>{{cite web |title=7 Reasons For Companion Planting |url=http://www.gardenandgreenhouse.net/articles/september-2017/7-reasons-companion-planting/ |website=Garden & Greenhouse |access-date=12 July 2018}}</ref> It is also a technique frequently used in [[permaculture]], together with [[mulch]]ing, [[polyculture]], and [[intercropping|changing of crops]].<ref>{{cite web |title=Companion Planting Guide |url=https://wheelbarrowexpert.com/companion-planting-guide/ |website=Mel's Garden |access-date=12 July 2018|date=2018-07-11 }}</ref>"}},
{"article_title": "Two-stroke engine", "pageid": "82156", "revid": "1061446099", "timestamp": "2021-12-21T19:28:13Z", "history_paths": [["Two-stroke engine --- Introduction ---", "History"]], "categories": ["two-stroke engine technology", "all articles with unsourced statements", "engine technology", "internal combustion piston engines", "motorcycle engines", "piston ported engines"], "heading_tree": {"Two-stroke engine --- Introduction ---": {"History": {}, "Emissions": {}, "Applications": {}, "Different two-stroke design types": {"Piston-controlled inlet port": {}, "Reed inlet valve": {}, "Rotary inlet valve": {}, "Cross-flow scavenging": {}, "Loop scavenging": {}, "Uniflow scavenging": {}, "Stepped piston engine": {}}, "Power-valve systems": {}, "Direct injection": {}, "Diesel": {}, "Lubrication": {}, "Two-stroke reversibility": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Two-stroke engine --- Introduction ---|History": "The first commercial two-stroke engine involving cylinder compression is attributed to [[Scotland|Scottish]] engineer [[Dugald Clerk]], who patented his design in 1881.<ref>See:\n*  Clerk, Dugald ; English patent no. 1,089 (issued:  March 14, 1881).\n*  Clerk, Dugald [https://pdfpiw.uspto.gov/.piw?Docid=00249307 "Motor worked by combustible gas or vapor,"] U.S. patent no. 249,307 (filed:  September 2, 1881 ; issued:  November 8, 1881).</ref> However, unlike most later two-stroke engines, his had a separate charging cylinder. The [[crankcase]]-scavenged engine, employing the area below the piston as a charging pump, is generally credited to Englishman [[Joseph Day (inventor)|Joseph Day]].<ref>See:\n*  Day, Joseph ; British patent no. 6,410 (issued: April 14, 1891).\n*  Day, Joseph ; British patent no. 9,247 (issued: July 1, 1891).\n*  Day, Joseph [https://pdfpiw.uspto.gov/.piw?docid=00543614 "Gas-engine"] US patent no. 543,614 (filed:  May 21, 1892 ; issued:  July 30, 1895).\n*  {{cite journal |last1=Torrens |first1=Hugh S. |title=A study of 'failure' with a 'successful innovation': Joseph Day and the two-stroke internal combustion engine |journal=Social Studies of Science |date=May 1992 |volume=22 |issue=2 |pages=245\u2013262|doi=10.1177/030631292022002004 |s2cid=110285769 }}</ref><ref>Joseph Day's engine used a reed valve.  One of Day's employees, Frederic Cock (1863\u20131944), found a way to render the engine completely valve-less. See:\n*  Cock, Frederic William Caswell ; British patent no. 18,513 (issued:  October 15, 1892).\n*  Cock, Frederic William Caswell [https://pdfpiw.uspto.gov/.piw?docid=00544210 "Gas-engine"] US patent no. 544,210 (filed:  March 10, 1894 ; issued: August 6, 1895).\n*  The Day-Cock engine is illustrated in: {{cite journal |last1=Dowson |first1=Joseph Emerson |title=Gas-power for electric lighting: Discussion |journal=Minutes of Proceedings of the Institution of Civil Engineers |date=1893 |volume=112 |pages=2\u2013110 |doi=10.1680/imotp.1893.20024 |url=https://babel.hathitrust.org/cgi/pt?id=hvd.hxgrpu&view=1up&seq=60}} ; see p. 48.</ref> On 31 December 1879, [[Germany|German]] [[inventor]] [[Karl Benz]] produced a two-stroke gas engine, for which he received a patent in 1880 in Germany. The first truly practical two-stroke engine is attributed to Yorkshireman [[Alfred Angas Scott]], who started producing [[twin cylinder|twin-cylinder]] [[water cooled|water-cooled]] [[motorcycle]]s in 1908.<ref>{{cite book|last1=Clew|first1=Jeff|title=The Scott Motorcycle: The Yowling Two-Stroke|date=2004|publisher=Haynes Publishing|isbn=0854291644|pages=240}}</ref>\n\nTwo-stroke [[gasoline]] engines with electrical [[spark ignition]] are particularly useful in lightweight or portable applications such as [[chainsaws]] and motorcycles. However, when weight and size are not an issue, the cycle's potential for high [[thermodynamic efficiency]] makes it ideal for [[diesel fuel|diesel]] [[compression ignition]] engines operating in large, weight-insensitive applications, such as [[marine propulsion]], [[locomotive|railway locomotives]], and [[Diesel generator|electricity generation]]. In a two-stroke engine, the exhaust gases transfer less heat to the cooling system than a four-stroke, which means more energy to drive the piston, and if present, a turbocharger."}},
{"article_title": "Chiptune", "pageid": "83463", "revid": "1062925256", "timestamp": "2021-12-31T05:58:47Z", "history_paths": [["Chiptune --- Introduction ---", "History"]], "categories": ["video game culture", "video game terminology", "video game music technology", "chiptune", "demoscene", "electronica", "1970s in music", "1980s in music", "1990s in music", "2000s in music", "2010s in music", "2020s in music"], "heading_tree": {"Chiptune --- Introduction ---": {"Technology": {}, "History": {"Video game origins": {}, "FM synthesis": {}, "SID music culture": {}}, "Mainstream popularity": {}, "Tracker chiptunes": {}, "Contemporary chiptune music": {}, "Live performances": {"MAGFest and Chipspace": {}}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Chiptune --- Introduction ---|History": "The earliest precursors to chip music can be found in the early history of [[computer music]]. In 1951, the computers [[CSIRAC]] and [[Ferranti Mark 1]] were used to perform real-time synthesized digital music in public.<ref>\n{{cite news\n|title=17 June 2008: 'Oldest' computer music unveiled\n|last=Fildes\n|first=Jonathan\n|url=http://news.bbc.co.uk/2/hi/technology/7458479.stm\n|work=BBC News\n|date=2008-06-17\n|access-date=2010-07-09\n}}\n</ref>\nOne of the earliest commercial computer music albums came from the First Philadelphia Computer Music Festival, held August 25, 1978, as part of the Personal Computing '78 show. The First Philadelphia Computer Music Festival recordings were published by Creative Computing in 1979.<ref>\n{{cite web\n|title=First Philadelphia Computer Music Festival\n|url=https://vintagecomputermusic.com\n|website=Vintage Computer Music.com\n}}\n</ref>\nThe [[Global TV]] program ''[[Science International]]'' (1976\u20131979) credited a [[PDP-11|PDP-11/10]] for the music.<ref>\n{{cite web\n|title=Science International (What Will They Think Of Next)\n|url=https://youtube.com/watch?v=kPzA2jkN0vs\n|last=bmuz\n|via=YouTube\n}}\n</ref>\n\nBy the early 1980s, [[personal computer]]s had become less expensive and more accessible than they had been previously. This led to a proliferation of outdated personal computers and game consoles that had been abandoned by consumers as they upgraded to newer machines. They were in low demand by consumers as a whole, and thus were not difficult to find, making them a highly accessible and affordable method of creating sound or art. While it has been a mostly underground genre, chiptune has had periods of moderate popularity in the 1980s and 21st century, and has influenced the development of [[electronic dance music]].\n{{external media\n|float=right\n|video1=[https://youtube.com/watch?v=kPzA2jkN0vs&lc=CJKoHtM60L9wUdoAxfRE2dOhjSt8h2QdVNNECbuBPWk ''Science International'': ''What Will They Think Of Next?''], YouTube video\n}}\n\n Chiptune music began to appear with the [[video game music]] produced during the [[golden age of video arcade games]]. An early example was the opening tune in [[Tomohiro Nishikado]]'s [[arcade game]] ''[[Gun Fight]]'' (1975). The first video game to use a continuous background soundtrack was Tomohiro Nishikado's 1978 release ''[[Space Invaders]]'', which had four simple [[Diatonic and chromatic|chromatic]] descending [[bass note]]s repeating in [[music loop|a loop]], though it was dynamic and interacted with the player, increasing pace as the enemies descended on the player.<ref>\n<!--this is collins_2 not to be confused with pages 12 or 19 earlier or 10&11 later-->\n{{citation\n|title=From Pac-Man to pop music: interactive audio in games and new media\n|first=Karen\n|last=Collins\n|publisher=[[Ashgate Publishing]]\n|year=2008\n|isbn=978-0-7546-6200-6\n|url=https://google.com/books/edition/_/lFEYAQAAIAAJ\n|page=2\n}}\n</ref>\nThe first video game to feature continuous melodic [[background music]] was ''[[Rally-X]]'', an arcade game released by [[Namco]] in 1980, featuring a simple tune that repeats continuously during [[gameplay]].<ref name="gradar2">\n{{cite web\n|title=Gaming's most important evolutions\n|url=https://gamesradar.com/gamings-most-important-evolutions\n|date=2010-10-09\n|website=gamesradar\n}}\n</ref>\nIt was also one of the earliest games to use a [[digital-to-analog converter]] to produce [[Sampling (signal processing)|sampled]] sounds.<ref name="collins_12">\n<!--this is collins_12 not to be confused with pages 19 or 2 or 10&11 later-->\n{{cite book\n|title=Game sound: an introduction to the history, theory, and practice of video game music and sound design\n|last=Collins\n|first=Karen\n|year=2008\n|publisher=[[MIT Press]]\n|isbn=978-0-262-03378-7\n|page=12\n|url=https://google.com/books/edition/Game_Sound/gnw0Zb4St-wC?&pg=PA12\n|access-date=June 12, 2011\n}}\n</ref>\nThat same year, the first video game to feature [[speech synthesis]] was also released, [[Sunsoft]]'s [[shoot 'em up]] arcade game ''[[Stratovox]]''.<ref name="gradar2"/>\n\nIn the late 1970s, the pioneering [[synthpop]]/[[electronic dance music]] group [[Yellow Magic Orchestra]] (YMO) were using computers to produce synthesized music.<ref name="Sarasota">\n{{cite journal\n|title=Computer rock music gaining fans\n|url=https://news.google.com/newspapers?id=7s4mAAAAIBAJ&pg=4481,2128223\n|journal=[[Sarasota Journal]]\n|date=August 18, 1980\n|access-date=2011-05-25\n|page=8\n}}\n</ref>\nSome of their early music, including their 1978 self-titled [[Yellow Magic Orchestra (album)|debut album]], were [[Sampling (music)|sampling]] sounds from popular arcade games such as ''Space Invaders''<ref name="wire_1996">{{citation\n|title=A-Z Of Electro\n|work=[[The Wire (magazine)|The Wire]]\n|issue=145\n|date=March 1996\n|author=David Toop\n|url=https://thewire.co.uk/in-writing/essays/a-z-of-electro#V\n|access-date=2020-06-21\n|archive-url=https://web.archive.org/web/20190328142136/http://thewire.co.uk/in-writing/essays/a-z-of-electro#V\n|archive-date=March 28, 2019\n|url-status=live\n}}\n<!--\n|url=https://thewire.co.uk/articles/210\n|accessdate=2011-05-29\n--></ref> and ''Gun Fight''. In addition to incorporating sounds from contemporary video games into their music, the band would later have a major influence on much of the video game and chiptune music produced during the [[History of video game consoles (third generation)|8-bit]] and [[History of video game consoles (fourth generation)|16-bit eras]].<ref>{{cite web\n|title=YMCK takes 'chiptune' revolution major\n|url=http://search.japantimes.co.jp/cgi-bin/fm20080229a1.html\n|url-status=dead\n|date=February 29, 2008\n|author=Daniel Robson\n|work=[[The Japan Times]]\n|access-date=2011-06-11\n|archive-url=https://archive.today/20120629195429/http://www.japantimes.co.jp/text/fm20080229a1.html%23.T-4H2qgo_KA\n|archive-date=June 29, 2012\n}}\n</ref><ref>\n{{cite web\n|title=Game Music Roots: Yellow Magic Orchestra\n|url=http://1up.com/features/game-music-roots-yellow-magic\n|url-status=dead\n|archive-url=https://web.archive.org/web/20121019235737/http://www.1up.com/features/game-music-roots-yellow-magic\n|archive-date=October 19, 2012\n|last=Smith\n|first=David F.\n|website=[[1UP.com]]\n|access-date=6 August 2012\n|date=June 2012\n|df=mdy-all\n}}\n</ref>\n[[Sega]]'s 1982 arcade game ''[[Super Locomotive]]'', for example, featured a chiptune [[cover version]] of YMO's "[[Solid State Survivor|Rydeen]]" (1979);<ref>{{KLOV game|9910|Super Locomotive}}</ref> several later [[PC game|computer games]] also covered the song, such as  ''Trooper Truck'' (1983) by [[Rabbit Software]] as well as ''[[Daley Thompson's Decathlon]]'' (1984) and ''[[Stryker's Run]]'' (1986) arranged by [[Martin Galway]].\n\nBy 1983, [[Konami]]'s arcade game ''[[Gyruss]]'' utilized five sound chips along with a digital-to-analog converter, which were partly used to create an electronic rendition of [[Johann Sebastian Bach|J. S. Bach's]] ''[[Toccata and Fugue in D minor, BWV 565|Toccata and Fugue in D minor]]''.<ref>\n<!--this is collins_19 not to be confused with page 12 earlier or 2 and 10&11 later-->\n{{cite book\n|title=Game sound: an introduction to the history, theory, and practice of video game music and sound design\n|url=https://google.com/books/edition/_/gnw0Zb4St-wC?pg=PA19\n|last=Collins\n|first=Karen\n|year=2008\n|publisher=[[MIT Press]]\n|isbn=978-0-262-03378-7\n|page=19\n|access-date=June 12, 2011}}\n</ref>\nIn 1984, former YMO member [[Haruomi Hosono]] released an album produced entirely from Namco arcade game samples entitled ''Video Game Music'', an early example of a chiptune record<ref name="discogs_hosono">\n{{Discogs master\n|190001\n|Haruomi Hosono \u2013 Video Game Music\n|type=album\n}}\n</ref>\nand the first video game music album.<ref>{{cite web\n|title=Xevious\n|url=http://hardcoregaming101.net/xevious/xevious2.htm\n|url-status=dead\n|access-date=2011-06-11\n|publisher=Hardcore Gaming 101\n|page=2\n|author=Carlo Savorelli\n|archive-url=https://web.archive.org/web/20180322111516/http://www.hardcoregaming101.net/xevious/xevious2.htm\n|archive-date=March 22, 2018\n}}</ref>\nThe record featured the work of Namco's chiptune composers: Toshio Kai (''[[Pac-Man]]'' in 1980), Nobuyuki Ohnogi (''[[Galaga]]'', ''[[New Rally-X]]'' and ''[[Bosconian]]'' in 1981, and ''[[Pole Position (video game)|Pole Position]]'' in 1982), and Yuriko Keino (''[[Dig Dug]]'' and ''[[Xevious]]'' in 1982).<ref name="vgmdb_namco">\n{{cite web\n|title=Video Game Music\n|url=http://vgmdb.net/album/489\n|work=VGMdb\n|access-date=September 6, 2011\n}}\n</ref>\n\n A major advance for chip music was the introduction of [[frequency modulation synthesis]] (FM synthesis), first commercially released by [[Yamaha]] for their [[digital synthesizer]]s and FM [[sound chip]]s, which began appearing in arcade machines from the early 1980s.<ref name="karen_10-1">\n<!--this is collins_10&11 not to be confused with pages 12, 19, or 2 earlier-->\n{{cite book\n|title=Game sound: an introduction to the history, theory, and practice of video game music and sound design\n|url=https://google.com/books/edition/_/gnw0Zb4St-wC&pg=PA10\n|access-date=June 12, 2011\n|last=Collins\n|first=Karen\n|year=2008\n|publisher=[[MIT Press]]\n|isbn=978-0-262-03378-7\n|pages=10\u20131\n}}\n</ref><ref>\n{{cite web\n|title=The Magic of FM Synth\n|url=https://1up.com/features/the-magic-of-fm-synth\n|url-status=dead\n|archive-url=https://web.archive.org/web/20130124112215/http://www.1up.com/features/the-magic-of-fm-synth\n|archive-date=January 24, 2013\n|access-date=6 August 2012\n|date=June 2012\n|last=Barnholt\n|first=Ray\n|website=[[1UP.com]]\n|df=mdy-all\n}}\n</ref>\nArcade game composers utilizing FM synthesis at the time included Konami's [[Miki Higashino]] (''[[Gradius]]'', ''[[Yie-Ar Kung Fu]]'', ''[[Teenage Mutant Ninja Turtles (arcade game)|Teenage Mutant Ninja Turtles]]'') and [[Sega]]'s [[Hiroshi Kawaguchi (composer)|Hiroshi Kawaguchi]] (''[[Space Harrier]]'', ''[[Hang-On]]'', ''[[Out Run]]'').\n\nBy the early 1980s, significant improvements to [[personal computer game]] music were made possible with the introduction of [[Digital synthesizer|digital]] FM synthesis sound. [[Yamaha]] began manufacturing FM [[Sound card|synth boards]] for Japanese computers such as the [[NEC PC-8801]] and [[NEC PC-9801|PC-9801]] in the early 1980s, and by the mid-1980s, the PC-8801 and [[FM-7]] had built-in FM sound. This allowed computer game music to have greater complexity than the simplistic [[Beep (sound)|beeps]] from internal speakers. These FM synth boards produced a "warm and pleasant sound" that musicians such as [[Yuzo Koshiro]] and [[Takeshi Abo]] utilized to produce music that is still highly regarded within the chiptune community.<ref name="hg101_retro">\n{{cite web\n|title=Retro Japanese Computers: Gaming's Final Frontier\n|url=https://hardcoregaming101.net/JPNcomputers/Japanesecomputers.htm\n|access-date=2011-03-29\n|author=John Szczepaniak\n|publisher=Hardcore Gaming 101\n}}\nReprinted from\n{{citation\n|title=[[Retro Gamer]]\n|issue=67\n|year=2009}}\n</ref>\nIn the early 1980s, Japanese [[personal computer]]s such as the NEC PC-88 and PC-98 featured [[audio programming language]]s such as [[Music Macro Language]] (MML) and [[MIDI]] interfaces, which were most often used to produce video game music.<ref name="shimazu104">\n{{cite journal\n|title=The History of Electronic and Computer Music in Japan: Significant Composers and Their Works\n|url=https://muse.jhu.edu/article/585311/pdf\n|access-date=11 October 2018\n|last=Shimazu\n|first=Takehito\n|journal=[[Leonardo Music Journal]]\n|year=1994\n|volume=4\n|pages=102\u2013106 [104]\n|publisher=[[MIT Press]]\n|doi=10.2307/1513190\n|jstor=1513190\n|s2cid=193084745\n}}\n</ref>\n\n[[Fujitsu]] also released the ''FM Sound Editor'' software for the FM-7 in 1985, providing users with a user-friendly interface to create and edit synthesized music.<ref>\n{{cite web\n|title=FM Sound Editor V1.0\n|url=http://retropc.net/fm-7/museum/softhouse/fujitsu/520200300.html\n|url-status=dead\n|archive-url=https://web.archive.org/web/20071109175447/http://retropc.net/fm-7/museum/softhouse/fujitsu/520200300.html\n|archive-date=November 9, 2007\n|access-date=2012-09-02\n|date=2003-05-20\n|work=[[:jp:Oh!FM|Oh!FM]]\n|df=ymd-all\n}}</ref>\n\nIn 1987, FM synthesis became available for Western computers when Canadian company [[Ad Lib, Inc.| Ad Lib]] released the AdLib Music Synthesizer Card for the [[IBM Personal Computer]],<ref>{{cite web |title=AdLib Music Synthesizer Card |url=http://www.computinghistory.org.uk/det/23724/AdLib-Music-Synthesizer-Card/ |website=Centre for Computing History |access-date=24 December 2020}}</ref> while Singapore-based [[Creative Labs]] incorporated the AdLib card's sound chip into its [[Sound Blaster]] card in 1989.<ref>{{cite news |last1=Hardwidge |first1=Ben |title=The Sound Blaster Story |url=https://custompc.raspberrypi.org/articles/the-sound-blaster-story |access-date=24 December 2020 |publisher=Custom PC}}</ref> Both cards were widely supported by [[MS-DOS]] game developers in the late 1980s and early 1990s.\n\nThe widespread adoption of FM synthesis by consoles would later be one of the major advances of the [[History of video game consoles (fourth generation)|16-bit era]], by which time 16-bit arcade machines were using multiple FM synthesis chips.<ref name="karen_10-1"/> A major chiptune composer during this period was [[Yuzo Koshiro]].<ref name="santos_2006">\n{{cite journal\n|last=Santos\n|first=Wayne\n|title=Songs & Sounds In The 21st Century\n|journal=GameAxis Unwired\n|date=December 2006\n|issue=40\n|page=39\n|publisher=[[Singapore Press Holdings|SPH Magazines]]\n|issn=0219-872X\n|url=https://google.com/books/edition/_/EOkDAAAAMBAJ&pg=PA39\n|access-date=2011-08-05\n}}\n</ref>\nDespite later advances in audio technology, he would continue to use older PC-8801 hardware to produce chiptune soundtracks for series such as ''[[Streets of Rage (series)|Streets of Rage]]'' (1991\u20131994) and ''[[Etrian Odyssey]]'' (2007\u2013present).<ref name="hg101_retro"/> His soundtrack to ''[[The Revenge of Shinobi (1989 video game)|The Revenge of Shinobi]]'' (1989) featured [[House music|house]]<ref name="greening_kotowski">\n{{cite web\n|title=Interview with Yuzo Koshiro\n|date=February 2011\n|publisher=Square Enix Music Online\n|last1=Greening\n|last2=Kotowski\n|first1=Chris\n|first2=Don\n|url=http://www.squareenixmusic.com/features/interviews/yuzokoshiro.shtml\n|access-date=2011-06-20\n}}\n</ref><ref>\n{{cite web\n|url=https://www.allgame.com/game.php?id=3322|title=Yuzo Koshiro\n|archive-url=https://web.archive.org/web/20140101010101/https://www.allgame.com/game.php?id=3322|archive-date=2014-01-01|url-status=dead\n|website=[[All Media Network#AllGame|AllGame]]\n}}\n</ref>\nand [[Progressive electronic dance music|progressive]] [[techno]] compositions<ref name="santos_2006"/> that fused [[electronic dance music]] with traditional [[Music of Japan|Japanese music]].<ref>\n{{cite web\n|title=Interview with Yuzo Koshiro\n|url=http://www.squareenixmusic.com/composers/koshiro/oct99interview.shtml\n|publisher=Square Enix Music Online\n|access-date=8 August 2011\n|author=RocketBaby\n|date=October 1999\n}}\n</ref>\n[[Discography of the Streets of Rage series|The soundtrack]] for ''[[Streets of Rage 2]]'' (1992) is considered "revolutionary" and "ahead of its time" for its "[[electro house|blend of]] swaggering house [[synthesizer|synths]], [[electro house|dirty]] [[electro (music)|electro-funk]] and [[trance music|trancey]] electronic textures that would feel as comfortable in a [[nightclub]] as a video game."<ref>\n{{cite web\n|title=Game music of the day: Streets of Rage 2\n|url=http://www.gamesradar.com/game-music-of-the-day-streets-of-rage-2\n|access-date=28 July 2012\n|date=April 19, 2010\n|last=McNeilly\n|first=Joe\n|publisher=[[GamesRadar]]\n}}\n</ref>\nFor the soundtrack to ''[[Streets of Rage 3]]'' (1994), Koshiro created a new composition method called the "Automated Composing System" to produce "fast-beat techno like [[Drum and bass|jungle]]",<ref name="jeff_davis">\n{{cite web\n|title=Interview with Yuzo Koshiro\n|url=https://thegia.com/features/f010123.html\n|url-status=dead\n|archive-url=https://web.archive.org/web/20010131055900/http://thegia.com/features/f010123.html\n|archive-date=January 31, 2001\n|access-date=6 August 2011\n|last=Davis\n|first=Jeff\n|work=Gaming Intelligence Agency\n|df=mdy-all\n}}\n<!--|url=https://psy-q.ch/mirrors/thegia/sites/thegia.com/features/f010123.html--></ref>\nresulting in innovative and [[Experimental music|experimental sounds]] generated automatically.<ref name="sega_horowitz">\n{{cite web\n|title=Interview: Yuzo Koshiro\n|url=https://sega-16.com/feature_page.php?id=136&title=Interview:+Yuzo+Koshiro\n|url-status=dead\n|archive-url=https://web.archive.org/web/20080921205228/http://sega-16.com/feature_page.php?id=136&title=Interview%3A+Yuzo+Koshiro\n|archive-date=September 21, 2008\n|access-date=6 August 2011\n|date=February 5, 2008\n|df=mdy-all\n|last=Horowitz\n|first=Ken\n|work=Sega-16\n}}</ref>\nKoshiro also composed chiptune soundtracks for series such as ''[[Dragon Slayer (series)|Dragon Slayer]]'', ''[[Ys (video game)|Ys]]'', ''[[Shinobi (series)|Shinobi]]'', and ''[[ActRaiser]]''. Another important FM synth composer was the late [[Ryu Umemoto]], who composed chiptune soundtracks for various [[visual novel]] and [[shoot 'em up]] games.<ref>\n{{cite web\n|title=A Dragon's Journey: Ryu Umemoto in Europe\n|url=https://hardcoregaming101.net/umemoto/umemoto.htm\n|url-status=dead\n|access-date=2011-08-23\n|author=Audi\n|publisher=Hardcore Gaming 101\n|archive-url=https://web.archive.org/web/20170726130608/http://www.hardcoregaming101.net/umemoto/umemoto.htm\n|archive-date=July 26, 2017\n}}</ref>\n\n {{See also|MOS Technology SID|Demoscene}}\n[[file:MOS Technologies 6581.jpg|thumb|MOS 6581 and 8580 Commodore 64 SID chips.]]\nLater on, several demo groups moved to using their own music instead of ripped game music. In 1986, Jeroen "Red" Kimmel studied Rob Hubbard's player routine and used it for original demo songs<ref>\n{{cite web\n|title=Kimmel, Jeroen "Red": Red Hubbard (C-64 demo)\n|url=http://noname.c64.org/csdb/release/?id=14758\n|access-date=2010-07-09\n|publisher=Noname.c64.org\n}}\n</ref>\nbefore writing a routine of his own in 1987. Hobbyists were also writing their own dedicated music editor software, such as [[Chris H\u00fclsbeck]]'s ''Soundmonitor'' which was released as a type-in listing in a 1986 issue of the German C-64 magazine ''[[64'er]]''.<ref>\n{{cite web\n|title=H\u00fclsbeck, Chris: Soundmonitor 1.0 (C-64 program)\n|url=http://noname.c64.org/csdb/release/?id=59929\n|access-date=2010-07-09\n|publisher=Noname.c64.org\n}}\n</ref>\n\nThe practice of SID music composition has continued seamlessly until this day in conjunction with the [[Commodore 64]] demoscene. [[The High Voltage SID Collection]], a comprehensive archive of SID music, contains over 40,000 pieces of SID music.<ref>\n[http://www.hvsc.de/#faq High Voltage SID Collection FAQ] {{webarchive|url=https://web.archive.org/web/20120722121810/http://www.hvsc.de/ |date=July 22, 2012 }}</ref>"}},
{"article_title": "Centrifugal governor", "pageid": "84130", "revid": "1021018424", "timestamp": "2021-05-02T12:50:00Z", "history_paths": [["Centrifugal governor --- Introduction ---", "History"]], "categories": ["steam engine governors", "mechanisms (engineering)", "control devices", "cybernetics", "mechanical power control", "rotating machines", "scottish inventions", "british inventions", "inventions by christiaan huygens", "science and technology in the dutch republic"], "heading_tree": {"Centrifugal governor --- Introduction ---": {"Operation": {"Non-gravitational regulation": {}}, "History": {}, "Dynamic systems": {"Natural selection": {}}, "Culture": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Centrifugal governor --- Introduction ---|History": "[[File:Boulton and Watt centrifugal governor-MJ.jpg|thumb|right|Boulton & Watt engine of 1788]]\nJames Watt designed his first governor in 1788 following a suggestion from his business partner [[Matthew Boulton]]. It was a [[conical pendulum]] governor and one of the final series of innovations Watt had employed for steam engines. James Watt never claimed the centrifugal governor to be an invention of his own. A giant statue of Watt's governor stands at [[Smethwick]] in the [[England|English]] [[West Midlands (county)|West Midlands]]. It is known as the flyball governor.\n\nCentrifugal governors are also used in many modern [[Repeater (horology)|repeating watches]] to limit the speed of the [[Striking clock#Parts of mechanism|striking train]], so the repeater doesn't run too quickly.\n\nAnother kind of centrifugal governor consists of a pair of masses on a spindle inside a cylinder, the masses or the cylinder being coated with pads, somewhat like a [[drum brake]]. This is used in a spring-loaded [[record player]] and a spring-loaded [[telephone]] dial to limit the speed."}},
{"article_title": "Closed-circuit television", "pageid": "87179", "revid": "1062817583", "timestamp": "2021-12-30T18:36:48Z", "history_paths": [["Closed-circuit television --- Introduction ---", "History"]], "categories": ["applications of computer vision", "assistive technology", "crime prevention", "law enforcement techniques", "physical security", "public safety", "security engineering", "security technology", "surveillance", "video surveillance", "video", "warning systems", "telecommunications-related introductions in 1942"], "heading_tree": {"Closed-circuit television --- Introduction ---": {"History": {"Technology": {}, "Application": {}}, "Uses": {"Crime prevention": {}, "Crime solving": {}, "Body worn": {}, "Traffic flow monitoring": {}, "Vehicle traffic": {}, "Pedestrian traffic": {}, "Management of infection": {}, "Increasing safety and security in public transport": {}, "Sporting events": {}, "Employee monitoring": {}, "Use in schools": {}, "Use in private homes": {}, "Criminal use": {}, "Use in shopping malls & retail stores": {}}, "Prevalence": {"Asia": {}, "United States": {}, "United Kingdom": {}, "Canada": {}, "South Africa": {}, "Latin America": {}, "Russia": {}}, "Video surveillance and terrorism": {}, "Privacy": {}, "Technological developments": {"Computer-controlled analytics and identification": {}, "Retention, storage and preservation": {}, "IP cameras": {}, "Networking CCTV cameras": {}, "Wireless security cameras": {}, "Talking CCTV": {}}, "Countermeasures": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Closed-circuit television --- Introduction ---|History": "[[File:THE CENTRAL POLICE CONTROL STATION, MANNED 24 HOURS A DAY CONTROLS ALL TRAFFIC LIGHTS, RECEIVES REMOTE TV INPUTS FROM... - NARA - 551905.tif|thumb|Closed circuit TV monitoring at the Central Police Control Station, Munich Germany in 1973.]]\n[[File:Cameratoezichtcentrale politie nederland.jpg|thumb|Desk in one of the regional control-rooms of the National Police in the Netherlands in 2017.]]\n[[File:CCTV control room monitor wall.jpg|thumb|CCTV control-room monitor wall for 176 open-street cameras in 2017.]]\nAn early [[Mechanical television|mechanical]] CCTV system was developed in June 1927 by Russian physicist [[L\u00e9on Theremin]]<ref name=":0">{{Cite book|title=Theremin : ether music and espionage|last=Glinsky, Albert.|date=2000|publisher=University of Illinois Press|isbn=0252025822|location=Urbana|pages=46\u201347|oclc=43286443}}</ref> (cf. [[Television in the Soviet Union]]). Originally requested by the Soviet of Labor and Defense, the system consisted of a manually-operated scanning-transmitting camera and wireless shortwave transmitter and receiver, with a resolution of a hundred lines. Having been commandeered by [[Kliment Voroshilov]], Theremin's CCTV system was demonstrated to [[Joseph Stalin]], [[Semyon Budyonny]], and [[Sergo Ordzhonikidze]], and subsequently installed in the courtyard of the [[Moscow Kremlin]] to monitor approaching visitors.<ref name=":0" />\n\nAnother early CCTV system was installed by [[Siemens|Siemens AG]] at [[Test Stand VII]] in [[Peenem\u00fcnde]], Nazi Germany in 1942, for observing the launch of [[V-2 rocket]]s.<ref name="dornberger">[[Walter Dornberger|Dornberger, Walter]]: ''V-2'', [[Ballantine Books]] 1954, ASIN: B000P6L1ES, page 14.</ref>\n\nIn the U.S. the first commercial closed-circuit television system became available in 1949, called Vericon. Very little is known about Vericon except it was advertised as not requiring a government permit.<ref>[https://books.google.com/books?id=pCQDAAAAMBAJ&pg=PA179&dq=popular+science+1949+%22Some+time+ago%22&hl=en&ei=gZjhTI-wHZGUnweD79T6Dw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCoQ6AEwAA#v=onepage&q&f=true '' "Television Rides Wires" '', February 1949, Popular Science] small article, bottom of page 179</ref>\n\n The earliest video surveillance systems involved constant monitoring because there was no way to record and store information. The development of reel-to-reel media enabled the recording of surveillance footage. These systems required magnetic tapes to be changed manually, which was a time-consuming, expensive and unreliable process, with the operator having to manually thread the tape from the tape reel through the recorder onto an empty take-up reel. Due to these shortcomings, video surveillance was not widespread. [[VCR]] technology became available in the 1970s, making it easier to record and erase information, and the use of video surveillance became more common.<ref>{{cite book|url=https://books.google.com/books?id=DaQY8CrmqFcC&pg=PA276 |title=CCTV Surveillance|isbn=9780080468181|last1=Kruegle|first1=Herman|date=15 March 2011}}</ref>\n\nDuring the 1990s, digital [[multiplexing]] was developed, allowing several cameras to record at once, as well as [[Time lapse photography|time lapse]] and motion-only recording. This saved time and money which then led to an increase in the use of CCTV.<ref name="wecusurveillance.com"/>\n\nRecently CCTV technology has been enhanced with a shift toward Internet-based products and systems, and other technological developments.<ref>{{cite web | url=http://fennoturvapalvelut.com/ | title=Internet based CCTV on cloud services|language=fi|date=27 March 2015|publisher=fennoturvapalvelut}}</ref>\n\n Closed-circuit television was used as a form of [[pay-per-view]] [[theatre television]] for sports such as [[professional boxing]] and [[professional wrestling]], and from 1964 through 1970, the [[Indianapolis 500]] automobile race. Boxing telecasts were broadcast live to a select number of venues, mostly theaters, where viewers paid for tickets to watch the fight live.<ref name="Ezra">{{cite book|last=Ezra|first=Michael|title=The Economic Civil Rights Movement: African Americans and the Struggle for Economic Power|date=2013|publisher=[[Routledge]]|isbn=9781136274756|page=105|url=https://books.google.com/books?id=DL41bsCigZcC&pg=PA105|language=en}}</ref><ref name="bloodyelbow">{{cite news|title=History of Prizefighting's Biggest Money Fights|url=https://www.bloodyelbow.com/2017/8/24/16170894/history-of-prizefightings-biggest-money-fights-boxing-mma-ufc|work=[[Bloody Elbow]]|agency=[[SB Nation]]|date=24 August 2017}}</ref> The first fight with a closed-circuit telecast was [[Joe Louis]] vs. [[Jersey Joe Walcott|Joe Walcott]] in 1948.<ref>{{cite book|title=Television|date=1965|publisher=Frederick A. Kugel Company|page=78|url=https://books.google.com/books?id=it0aAQAAMAAJ&q=Louis+Walcott|language=en|quote=Teleprompter's main-spring, Irving B. Kahn (he's chairman of the board and president), had a taste of closed circuit operations as early as 1948. That summer, Kahn, then a vice president of 20th Century-Fox, negotiated what was probably the first inter-city closed circuit telecast in history, a pickup of the Joe Louis-Joe Walcott fight.}}</ref> Closed-circuit telecasts peaked in popularity with [[Muhammad Ali]] in the 1960s and 1970s,<ref name="Ezra"/><ref name="bloodyelbow"/> with "[[The Rumble in the Jungle]]" fight drawing 50{{nbsp}}million CCTV viewers worldwide in 1974,<ref>{{cite news|title=Zaire's fight promotion opens new gold mines|url=https://www.newspapers.com/newspage/28336306/|work=[[The Morning Herald]]|date=18 November 1974|language=en}}</ref> and the "[[Thrilla in Manila]]" drawing 100{{nbsp}}million CCTV viewers worldwide in 1975.<ref>{{cite journal|title=Karriem Allah|journal=[[Black Belt (magazine)|Black Belt]]|date=1976|page=35|url=https://books.google.com/books?id=XtUDAAAAMBAJ&pg=PA35|publisher=Active Interest Media, Inc.|language=en}}</ref> In 1985, the [[WrestleMania I]] professional wrestling show was seen by over one million viewers with this scheme.<ref>{{cite news|title=Wrestlemania In Photographs: 1-10|url=https://www.sportskeeda.com/wwe/wrestlemania-in-photographs-1-10|work=[[Sportskeeda]]|date=1 April 2017}}</ref> As late as 1996, the [[Julio C\u00e9sar Ch\u00e1vez vs. Oscar De La Hoya]] boxing fight had 750,000 viewers.<ref>[http://articles.chicagotribune.com/1996-06-07/sports/9606070183_1_closed-circuit-sites-las-vegas-oscar-de-la-hoya Chavez-De La Hoya Fight Is A Bout About Contrasts], Chicago Tribune article, 1996-06-07, Retrieved on 2015-02-23</ref> Although closed-circuit television was gradually replaced by [[pay-per-view]] home [[cable television]] in the 1980s and 1990s, it is still in use today for most awards shows and other events that are transmitted live to most venues but do not air as such on network television, and later re-edited for broadcast.<ref name="bloodyelbow"/>\n\n[[Marie Van Brittan Brown]] first pioneered and patented a CCTV home security system, much of the technology of which is still used in home security systems today (''{{US patent|3482037}}'').\n\nIn September 1968, [[Olean, New York]] was the first city in the United States to install video cameras along its main business street in an effort to fight crime.<ref name="Robb, Gary C. 1979 pg. 571-602">[Robb, Gary C. (1979) "Police Use of CCTV Surveillance: Constitutional Implications and Proposed Regulations" University of Michigan Journal of Law Reform. pg. 572]</ref> Another early appearance was in 1973 in [[Times Square]] in [[New York City]].<ref name="Yesil, Bilge">[Yesil, Bilge. (2006) "Watching Ourselves" Cultural Studies. Vol 20(4-5) pp. 400-416]</ref> The NYPD installed it to deter crime in the area; however, crime rates did not appear to drop much due to the cameras.<ref name="Yesil, Bilge"/> Nevertheless, during the 1980s video surveillance began to spread across the country specifically targeting public areas.<ref name="wecusurveillance.com">Roberts, Lucy. "[http://www.wecusurveillance.com/cctvhistory History of Video Surveillance and CCTV] {{Webarchive|url=https://web.archive.org/web/20191221172303/http://www.wecusurveillance.com/cctvhistory |date=21 December 2019 }}" We C U Surveillance Retrieved 2011-10-20</ref> It was seen as a cheaper way to deter crime compared to increasing the size of the police departments.<ref name="Yesil, Bilge"/> Some businesses as well, especially those that were prone to theft, began to use video surveillance.<ref name="Yesil, Bilge"/> From the mid-1990s on, police departments across the country installed an increasing number of cameras in various public spaces including housing projects, schools and public parks departments.<ref name="Yesil, Bilge"/> CCTV later became common in banks and stores to discourage theft, by recording evidence of criminal activity. In 1998, 3,000 CCTV systems were in use in New York City.<ref>{{cite news|title=You're being watched, New York!|url=http://news.bbc.co.uk/1/hi/world/americas/1865828.stm|publisher=BBC|date=11 March 2002}}</ref>\n\nExperiments in the UK during the 1970s and 1980s, including outdoor CCTV in [[Bournemouth]] in 1985, led to several larger trial programs later that decade. The first use by local government was in [[King's Lynn]], Norfolk, in 1987.<ref name=wndc>{{cite web|url=http://www.west-norfolk.gov.uk/default.aspx?page=21697|title=CCTV|last=Staff|date=August 2007|publisher=Borough Council of King's Lynn & West Norfolk|access-date=2008-12-14|url-status=dead|archive-url=https://web.archive.org/web/20090523184010/http://www.west-norfolk.gov.uk/default.aspx?page=21697|archive-date=23 May 2009}}</ref>"}},
{"article_title": "Screensaver", "pageid": "89769", "revid": "1060322918", "timestamp": "2021-12-14T20:22:07Z", "history_paths": [["Screensaver --- Introduction ---", "History"]], "categories": ["screensavers", "display technology", "utility software types"], "heading_tree": {"Screensaver --- Introduction ---": {"Purpose": {"Screen protection": {}, "Modern usage": {}}, "History": {}, "Underlying architecture": {"Microsoft Windows": {}, "MacOS": {}, "Atari": {}}, "Considerations": {}, "Entertainment": {"Microsoft Windows": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Screensaver --- Introduction ---|History": "Decades before the first computers using this technology were invented, [[Robert A. Heinlein]] gave an example of how they might be used in his novel ''[[Stranger In A Strange Land]]'' (1961):<ref>[http://www.technovelgy.com/ct/content.asp?Bnum=184 Screensaver (Inventor of) by Robert Heinlein from Stranger in a Strange Land] {{webarchive |url=https://web.archive.org/web/20150318155626/http://www.technovelgy.com/ct/content.asp?Bnum=184 |date=March 18, 2015 }}</ref><ref>{{cite book|last=Heinlein|first=Robert|title=Stranger in a Strange Land|year=1987|publisher=Penguin|location=New York, NY|isbn=9780441790340|pages=448|url=https://books.google.com/books?id=jBtDSf1VzQkC}}</ref>\n{{quote|Opposite his chair was a stereovision tank disguised as an aquarium; he switched it on, guppies and tetras gave way to the face of the well-known Winchell Augustus Greaves.}}\n\nThe first screensaver was allegedly written for the original [[IBM PC]] by [[John Socha]], best known for creating the [[Norton Commander]]; he also coined the term ''screen saver''. The screensaver, named ''scrnsave'', was published in the December 1983 issue of the [[Softalk]] magazine. It simply blanked the screen after three minutes of inactivity (an interval which could be changed by recompiling the program).\n\nBy 1983 a [[Zenith Data Systems]] executive included "screen-saver" among the new Z-29 [[computer terminal]]'s features, telling ''[[InfoWorld]]'' that it "blanks out the display after 15 minutes of nonactivity, preventing burned-in character displays".<ref name="chin19830411">{{Cite magazine |last=Chin |first=Kathy |date=1983-04-11 |title=Z-29, a new computer terminal from Zenith Data Systems |url=https://books.google.com/books?id=8S8EAAAAMBAJ&pg=PA13 |magazine=InfoWorld |language=en  |page=13}}</ref> The first screensaver that allowed users to change the activating time was released on [[Apple Computer|Apple]]'s [[Apple Lisa|Lisa]], in 1983.\n\nThe [[Atari 400]] and [[Atari 800|800's]] screens would also go through random screensaver-like color changes if they were left inactive for about 8 minutes. Normal users had no control over this, though programs did. These computers, released in 1979, are technically earlier "screen savers." Prior to these computers, games for the 1977 [[Atari 2600|Atari VCS/2600]] gaming console such as Combat and [[Breakout (video game)|Breakout]], included color cycling in order to prevent burn-in of game images into 1970s-era televisions. In addition, the first model of the [[TI-30]] calculator from 1976 featured a screensaver, which consisted of a decimal point running across the display after 30 seconds of inactivity. This was chiefly used to save battery power, as the TI-30 [[LED]] display was more power intensive than later [[LCD]] models. These are examples of screensavers in [[Read-only memory|ROM]] or the [[firmware]] of a computer.\n\n[[Android 4.2]] introduced "daydreams", screensavers that activate while the device is [[dock connector|docked]] or charging.<ref name="Walter">{{cite web |last1=Walter |first1=Derek |title=How to Set Up Android's Daydream Screensaver |url=https://www.tomsguide.com/us/android-daydream,review-3306.html |website=Tom's Guide |access-date=14 December 2021 |language=en |date=29 December 2015}}</ref><ref name="Hoffman">{{cite web |last1=Hoffman |first1=Chris |title=5+ Cool Uses for Android\u2019s Daydream Mode |url=https://www.howtogeek.com/170990/5-cool-uses-for-androids-daydream-mode/ |website=How-To Geek |access-date=14 December 2021 |language=en}}</ref>\n\nToday with the help of modern graphics technologies there is a wide variety of screensavers. Because of [[3D computer graphics]], which provide realistic environments, 3D screensavers are available."}},
{"article_title": "Military technology", "pageid": "90815", "revid": "1050611408", "timestamp": "2021-10-18T22:00:15Z", "history_paths": [["Military technology --- Introduction ---", "History"]], "categories": ["military technology", "military equipment"], "heading_tree": {"Military technology --- Introduction ---": {"History": {"Ancient technology": {}, "Post-classical technology": {}, "Modern technology": {"Armies": {}, "Naval": {}, "Organization and finance": {}}}, "Postmodern technology": {"Space": {}, "Mobilization": {}, "Defence": {}, "Sensors and communication": {}}, "Future technology": {"Emerging territory": {"Cyberspace": {}}}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Military technology --- Introduction ---|History": "{{Main|History of military technology}}This section is divided into the broad cultural developments that affected military technology.\n\n The first use of stone tools may have begun during the [[Paleolithic]] Period. The earliest stone tools are from the site of Lomekwi, Turkana, dating from 3.3 million years ago. Stone tools diversified through the [[Pleistocene]] Period, which ended ~12,000 years ago.<ref name=primitive>{{cite book|last1=Wescott|first1=David|title=Primitive Technology: A Book of Earth Skills|date=1999|publisher=Society of Primitive Technology, Gibbs Smith|location=Layton, UT|isbn=978-0-87905-911-8|page=60}}</ref>\nThe earliest evidence of warfare between two groups is recorded at the site of [[Nataruk]] in Turkana, Kenya, where human skeletons with major traumatic injuries to the head, neck, ribs, knees and hands, including an embedded obsidian bladelet on a skull, are evidence of inter-group conflict between groups of nomadic hunter-gatherers 10,000 years ago.<ref>{{Cite journal|title = Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya|journal = Nature|pages = 394\u2013398|volume = 529|issue = 7586|doi = 10.1038/nature16477|first1 = M. Miraz\u00f3n|last1 = Lahr|first2 = F.|last2 = Rivera|first3 = R. K.|last3 = Power|first4 = A.|last4 = Mounier|first5 = B.|last5 = Copsey|first6 = F.|last6 = Crivellaro|first7 = J. E.|last7 = Edung|first8 = J. M. Maillo|last8 = Fernandez|first9 = C.|last9 = Kiarie|pmid=26791728|year=2016|url = https://www.repository.cam.ac.uk/handle/1810/253726|bibcode = 2016Natur.529..394L|s2cid = 4462435}}</ref>\n\nHumans entered the [[Bronze Age]] as they learned to smelt copper into an alloy with tin to make weapons. In Asia where copper-tin ores are rare, this development was delayed until trading in bronze began in the third millennium [[BCE]]. In the Middle East and Southern European regions, the Bronze Age follows the [[Neolithic]] period, but in other parts of the world, the [[Copper Age]] is a transition from Neolithic to the Bronze Age. Although the Iron Age generally follows the Bronze Age, in some areas the [[Iron Age]] intrudes directly on the Neolithic from outside the region, with the exception of Sub-Saharan Africa where it was developed independently.<ref>[http://portal.unesco.org/en/ev.php-URL_ID=3432&URL_DO=DO_PRINTPAGE&URL_SECTION=201.html Iron In Africa: Revising The History : Unesco]. Portal.unesco.org. Retrieved on 2014-11-20.</ref>\n\nThe first large-scale use of iron weapons began in Asia Minor around the 14th century BCE and in Central Europe around the 11th century BCE followed by the Middle East (about 1000 BCE) and India and China.<ref name=Tucker2>{{cite book|last1=Tucker|first1=Spencer|title=A Global Chronology of Conflict|date=2010|publisher=ABC-CLIO, LLC|location=Santa Barbara, CA|isbn=978-1-85109-672-5|pages=6\u20137}}</ref>\n\nThe [[Assyria]]ns are credited with the introduction of horse cavalry in warfare and the extensive use of iron weapons by 1100 BCE. Assyrians were also the first to use iron-tipped arrows.<ref name=Tucker2 />\n\n{{Further|List of premodern combat weapons}}\n\n [[Image:Trebuchet1-intransit.jpg|alt=An ink on paper diagram of a trebuchet. A long arm with a spherical cap rests on top of a large square platform. The square platform is supported by four plain cut square beams, which connect to an open undercarriage. Rope hangs between the end of the pole that does not have the cap to the inside of the undercarriage, as far away from the start of the rope as possible. The assembly moves on four wheels attached to the sides of the undercarriage.|thumb|An illustration of a [[trebuchet]] catapult, as described in the ''[[Wujing Zongyao]]'' of 1044.]]\nThe ''[[Wujing Zongyao]]'' (''Essentials of the Military Arts''), written by Zeng Gongliang, Ding Du, and others at the order of [[Emperor Renzong of Song|Emperor Renzong]] around 1043 during the [[Song dynasty]] illustrate the eras focus on advancing intellectual issues and military technology due to the significance of warfare between the Song and the Liao, Jin, and Yuan to their north.  The book covers topics of military strategy, training, and the production and employment of advanced weaponry.<ref name=teacher>{{cite journal|title=Teachers' Guide for Military Technology|date=2001-11-26|page=1|url=http://depts.washington.edu/chinaciv/tg/tmiltech.pdf|access-date=2014-11-20}}</ref>\n\n[[Image:Chinese Flamethrower.JPG|alt=An ink on paper diagram of a flametrhower. It consists of a tube with multiple chambers mounted on top of a wooden box with four legs. How exactly the flamethrower would work is not apparent from the diagram alone.|thumb|A Chinese [[flamethrower]] from the ''[[Wujing Zongyao]]'' manuscript of 1044 CE, [[Song dynasty]].]]\n\nAdvances in military technology aided the [[Song dynasty]] in its defense against hostile neighbors to the north. The [[flamethrower]] found its origins in [[Byzantine]]-era [[Greece]], employing [[Greek fire]] (a chemically complex, highly [[flammable]] petrol fluid) in a device with a [[siphon]] hose by the 7th century.<ref name=pingyu>{{cite book|last1=Ping-Y\u00fc|first1=with the collaboration of Ho|last2=Gwei-Djen|first2=Lu|last3=Ling|first3=Wang|title=Science and Civilization in China. The Gunpowder Epic|date=1986|publisher=Cambridge U.P.|location=Cambridge|isbn=9780521303583|edition=1. publ.|url=https://books.google.com/books?id=hNcZJ35dIyUC|access-date=20 November 2014}}</ref>{{rp|77}}  The earliest reference to Greek Fire in China was made in 917, written by [[Wu Renchen]] in his ''[[Spring and Autumn Annals of the Ten Kingdoms]]''.<ref name=pingyu/>{{rp|80}}  In 919, the siphon projector-pump was used to spread the 'fierce fire oil' that could not be doused with water, as recorded by Lin Yu in his {{lang|zh-Latn|Wuyue Beishi}}, hence the first credible Chinese reference to the flamethrower employing the chemical solution of Greek fire (see also [[Pen Huo Qi]]).<ref name=pingyu/>{{rp|81}} Lin Yu mentioned also that the 'fierce fire oil' derived ultimately from one of China's maritime contacts in the 'southern seas', [[Arabia]] {{lang|zh-Latn|Dashiguo}}.<ref name=pingyu/>{{rp|82}} In the [[Battle of Langshan Jiang]] in 919, the naval fleet of the [[Qian Yuanguan|Wenmu King]] from [[Wuyue (Ten Kingdoms)|Wuyue]] defeated a [[Huainan]] army from the [[Wu (Ten Kingdoms)|Wu state]]; Wenmu's success was facilitated by the use of 'fire oil' ('huoyou') to burn their fleet, signifying the first Chinese use of [[gunpowder]] in a battle.<ref name=pingyu/>{{rp|81\u201383}} The Chinese applied the use of double-[[piston]] [[bellows]] to pump petrol out of a single cylinder (with an upstroke and downstroke), lit at the end by a slow-burning gunpowder match to fire a continuous stream of flame.<ref name=pingyu/>{{rp|82}} This device was featured in description and illustration of  the ''[[Wujing Zongyao]]'' military manuscript of 1044.<ref name=pingyu/>{{rp|82}} In the suppression of the [[Southern Tang]] state by 976, early Song naval forces confronted them on the Yangtze River in 975. Southern Tang forces attempted to use flamethrowers against the Song navy, but were accidentally consumed by their own fire when violent winds swept in their direction.<ref name=pingyu/>{{rp|89}}\n\n{{Further|Science and technology of the Song dynasty}}\n\nAlthough the destructive effects of gunpowder were described in the earlier [[Tang dynasty]] by a [[Taoism|Daoist]] [[alchemy|alchemist]], the earliest developments of the gun barrel and the projectile-fire [[cannon]] were found in late Song China. The first art depiction of the Chinese '[[fire lance]]' (a combination of a temporary-fire flamethrower and gun) was from a Buddhist mural painting of [[Dunhuang]], dated circa 950.<ref name="needham volume 5 part 7 224 225">Needham, Volume 5, Part 7, 224\u2013225.</ref> These 'fire-lances' were widespread in use by the early 12th century, featuring hollowed bamboo poles as tubes to fire sand particles (to blind and choke), lead pellets, bits of sharp metal and pottery shards, and finally large gunpowder-propelled arrows and [[rocket]] weaponry.<ref name=pingyu/>{{rp|220\u2013221}}  Eventually, perishable bamboo was replaced with hollow tubes of cast iron, and so too did the terminology of this new weapon change, from '[[fire lance|fire-spear]]' {{lang|zh-Latn|huo qiang}} to 'fire-tube' {{lang|zh-Latn|huo tong}}.<ref name=pingyu/>{{rp|221}}  This ancestor to the gun was complemented by the ancestor to the cannon, what the Chinese referred to since the 13th century as the 'multiple bullets magazine erupter' {{lang|zh-Latn|bai zu lian zhu pao}}, a tube of bronze or cast iron that was filled with about 100 lead balls.<ref name=pingyu/>{{rp|263\u2013264}}\n\nThe earliest known depiction of a gun is a sculpture from a cave in [[Sichuan]], dating to 1128, that portrays a figure carrying a vase-shaped [[bombard (weapon)|bombard]], firing flames and a cannonball.<ref name=gwei>{{cite journal|first=Lu|last=Gwei-Djen|author2=Joseph Needham |author3=Phan Chi-Hsing |date=July 1988|journal=[[Technology and Culture]]|volume=29|issue=3|pages=594\u2013605|title=The Oldest Representation of a Bombard|doi=10.2307/3105275|jstor=3105275}}</ref> However, the oldest existent [[archaeological]] discovery of a metal barrel [[handgun]] is from the Chinese [[Heilongjiang]] excavation, dated to 1288.<ref name=pingyu/>{{rp|293}} The Chinese also discovered the explosive potential of packing hollowed cannonball shells with gunpowder. Written later by [[Jiao Yu]] in his ''[[Huolongjing]]'' (mid-14th century), this manuscript recorded an earlier Song-era cast-iron cannon known as the 'flying-cloud thunderclap eruptor' (fei yun pi-li pao). The manuscript stated that:\n\nAs noted before, the change in terminology for these new weapons during the Song period were gradual. The early Song cannons were at first termed the same way as the Chinese [[trebuchet]] [[catapult]]. A later [[Ming dynasty]] scholar known as [[Mao Yuanyi]] would explain this use of terminology and true origins of the cannon in his text of the ''[[Wubei Zhi]]'', written in 1628:\n\nThe 14th-century ''[[Huolongjing]]'' was also one of the first Chinese texts to carefully describe to the use of explosive [[land mine]]s, which had been used by the late Song Chinese against the Mongols in 1277, and employed by the [[Yuan dynasty]] afterwards. The innovation of the detonated land mine was accredited to one Luo Qianxia in the campaign of defense against the Mongol invasion by [[Kublai Khan]],<ref name=pingyu/>{{rp|192}} Later Chinese texts revealed that the Chinese land mine employed either a rip cord or a motion [[booby trap]] of a pin releasing falling weights that rotated a steel [[wheellock|flint wheel]], which in turn created sparks that ignited the train of [[Fuse (explosives)|fuses]] for the land mines.<ref name=pingyu/>{{rp|199}}  Furthermore, the Song employed the earliest known gunpowder-propelled [[rocket]]s in warfare during the late 13th century,<ref name=pingyu/>{{rp|477}} its earliest form being the archaic [[Fire Arrow]]. When the Northern Song capital of Kaifeng fell to the Jurchens in 1126, it was written by Xia Shaozeng that 20,000 fire arrows were handed over to the Jurchens in their conquest.  An even earlier Chinese text of the ''[[Wujing Zongyao]]'' ("Collection of the Most Important Military Techniques"), written in 1044 by the Song scholars Zeng Kongliang and Yang Weide, described the use of three spring or triple bow [[ballista|arcuballista]] that fired arrow bolts holding gunpowder packets near the head of the arrow.<ref name=pingyu/>{{rp|154}} Going back yet even farther, the {{lang|zh-Latn|Wu Li Xiao Shi}} (1630, second edition 1664) of Fang Yizhi stated that fire arrows were presented to [[Emperor Taizu of Song]] (r. 960\u2013976) in 960.<ref name=partington>{{cite book|last1=Partington|first1=J.R.|title=A History of Greek Fire and gunpowder|date=1960|publisher=Heffer|location=Cambridge|isbn=9780801859540|page=211|edition=Johns Hopkins paperback|url=https://books.google.com/books?id=sHGdq4rLSTEC|access-date=20 November 2014}}</ref>\n\n{{Further|Post-classical history}}\n\n \n [[File:Dardanelles Gun Turkish Bronze 15c.png|thumb|left|200px|The bronze [[Dardanelles Gun]] on display at [[Fort Nelson, Hampshire|Fort Nelson]] in Hampshire. Similar cannons were used by the [[Ottoman Empire|Ottoman Turks]] in the [[Fall of Constantinople|siege of Constantinople]] in 1453.]]\n[[File:Rocket warfare.jpg|thumb|250px|A painting showing the Mysorean army fighting the British forces with Mysorean rockets.<ref>{{cite news|title=Missiles mainstay of Pak's N-arsenal|url=http://articles.timesofindia.indiatimes.com/2008-04-21/india/27784965_1_cruise-missile-missile-program-hatf-viii|archive-url=https://web.archive.org/web/20120924125020/http://articles.timesofindia.indiatimes.com/2008-04-21/india/27784965_1_cruise-missile-missile-program-hatf-viii|url-status=dead|archive-date=24 September 2012|access-date=2011-08-30|work=[[The Times of India]]|date=21 April 2008}}</ref>]]\nThe Islamic [[gunpowder empires]] introduced numerous developed firearms, cannon and small arms. During the period of [[Proto-industrialization]], newly invented weapons were seen to be used in [[Mughal India]].\n\nRapid development in military technology had a dramatic impact on armies and navies in the industrialized world in 1740-1914.<ref>Max Boot, ''War made new: technology, warfare, and the course of history, 1500 to today'' (Penguin, 2006).</ref> For land warfare, cavalry faded in importance, while infantry became transformed by the use of highly accurate more rapidly loading rifles, and the use of smokeless powder. Machine guns were developed in the 1860s in Europe. [[Rocket artillery]] and the [[Mysorean rockets]], both pioneered by Indian Muslim [[Tipu Sultan]], became more powerful as new high explosives (based on nitroglycerin) arrived during the [[Anglo-Mysore Wars]], and the French introduced much more accurate rapid-fire field artillery. Logistics and communications support for land warfare dramatically improved with use of railways and telegraphs. Industrialization provided a base of factories that could be converted to  produce munitions, as well as uniforms, tents, wagons and essential supplies. Medical facilities were enlarged and reorganized based on improved hospitals and the creation of modern nursing,  typified by [[Florence Nightingale]] in Britain during the [[Crimean War]] of 1854-56.<ref>B.H. Liddell Hart, "Armed Forces in the Art of War: Armies", in J.P.T. Bury, ed., ''The New Cambridge Modern History: volume X: The Zenith of European Power 1830-70'' (1967), 302-330.</ref>\n\n Naval warfare was transformed by many innovations,<ref>Michael Lewis, "Armed Forces in the Art of War: Navies", in J.P.T. Bury, ed., ''The New Cambridge Modern History: Volume X: The Zenith of European Power 1830-70'' (1967), 274-301.</ref> most notably the coal-based steam engine, highly accurate long-range naval guns, heavy steel armour for battleships, mines, and the introduction of the torpedo, followed by the torpedo boat and the destroyer. Coal after 1900 was eventually displaced by more efficient oil, but meanwhile navies with an international scope had to depend on a network of coaling stations to refuel. The British Empire provided them in abundance, as did the French Empire to a lesser extent.  War colleges developed, as military theory became a specialty; cadets and senior commanders were taught the theories of Jomini, Clausewitz and Mahan, and engaged in tabletop war games. Around 1900, entirely new innovations such as submarines and airplanes appeared, and were quickly adapted to warfare by 1914. The British [[HMS Dreadnought (1906)|HMS ''Dreadnought'' (1906)]] incorporated so much of the latest technology in weapons, propulsion and armour that it at a stroke made all other battleships obsolescent.<ref>David K. Brown, ''Warrior to Dreadnought: Warship Development 1860\u20131905''(2003).</ref>\n\n New financial tools were developed to fund the rapidly increasing costs of warfare, such as popular bond sales and income taxes, and the funding of permanent research centers.<ref>Michael Howard, "The armed forces." In F.H. Hinsley, ed. \u2018\u2019The new Cambridge modern history: volume XI: 1870-1898" (1962) pp 204-42.</ref><ref>John Sumida, ''In Defence of Naval Supremacy: Finance, Technology, and British Naval Policy 1889-1914'' Naval Institute Press, 2014.</ref>  Many 19th century innovations were largely invented and promoted by lone individuals with small teams of assistants, such as [[David Bushnell]] and the submarine, [[John Ericsson]] and the battleship, [[Hiram Maxim]] and the machine gun, and [[Alfred Nobel]] and high explosives. By 1900 the military began to realize that they needed to rely much more heavily on large-scale research centers, which needed government funding.<ref>{{cite journal | last1 = McBride | first1 = William M. | year = 1992 | title = 'The Greatest Patron of Science'?: The Navy-Academia Alliance and US Naval Research, 1896-1923 | journal = Journal of Military History | volume = 56 | issue = 1| pages = 7\u201334 | doi=10.2307/1985709| jstor = 1985709 }}</ref>  They brought in leaders of organized innovation such as [[Thomas Edison]] in the U.S. and chemist [[Fritz Haber]] of the [[Kaiser Wilhelm Institute]] in Germany.<ref>{{cite journal | last1 = Jeffrey | first1 = Thomas E. | year = 2016 | title = 'Commodore' Edison Joins the Navy: Thomas Alva Edison and the Naval Consulting Board | journal = Journal of Military History | volume = 80 | issue = 2| pages = 411\u201346 }}</ref><ref>L.F. Haber, ''The poisonous cloud: chemical warfare in the First World War'' (Oxford UP, 1986).</ref>"}},
{"article_title": "Instructional design", "pageid": "91820", "revid": "1058976428", "timestamp": "2021-12-06T18:31:34Z", "history_paths": [["Instructional design --- Introduction ---", "History"], ["Instructional design --- Introduction ---", "Instructional Design history"]], "categories": ["applied psychology", "educational technology", "educational psychology", "learning", "pedagogy", "communication design", "curricula"], "heading_tree": {"Instructional design --- Introduction ---": {"History": {"Origins": {}, "1950s": {}, "1960s": {}, "1970s": {}, "1980s": {}, "1990s": {}, "2000 - 2010": {}, "2010 - 2020": {}}, "Instructional Design history": {}, "Robert Gagn\u00e9": {"Taxonomy": {}, "Nine events": {}, "Influence": {}}, "Learning design": {}, "Models": {"ADDIE process": {}, "Rapid prototyping": {}, "Dick and Carey": {}, "Guaranteed Learning": {}, "Other": {}}, "Motivational design": {"Motivation concepts": {}, "ARCS MODEL": {"Components": {"Attention": {}, "Relevance": {}, "Confidence": {}, "Satisfaction": {}}, "Motivational Design Process": {}}, "Motivating opportunities": {}}, "Influential researchers and theorists": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Instructional design --- Introduction ---|History": "As a field, instructional design is historically and traditionally rooted in [[cognitive]] and [[behavioral psychology]], though recently [[constructivism (learning theory)|constructivism]] has influenced thinking in the field.<ref>{{cite journal|last1=Mayer|first1=Richard E|year=1992|title=Cognition and instruction: Their historic meeting within educational psychology|journal=Journal of Educational Psychology|volume=84|issue=4|pages=405\u2013412|doi=10.1037/0022-0663.84.4.405}}</ref><ref>Duffy, T. M., & Cunningham, D. J. (1996). Constructivism: Implications for the design and delivery of instruction. In D. Jonassen (Ed.), Handbook of Research for Educational Communications and Technology (pp. 170-198). New York: Simon & Schuster Macmillan</ref><ref>Duffy, T. M., & Jonassen, D. H. (1992). Constructivism: New implications for instructional technology. In T. Duffy & D. Jonassen (Eds.), Constructivism and the technology of instruction (pp. 1-16). Hillsdale, NJ: Erlbaum.</ref> This can be attributed to the way it emerged during a period when the behaviorist paradigm was dominating American psychology. There are also those who cite that, aside from behaviorist psychology, the origin of the concept could be traced back to [[systems engineering]]. While the impact of each of these fields is difficult to quantify, it is argued that the language and the "look and feel" of the early forms of instructional design and their progeny were derived from this engineering discipline.<ref>{{Cite book|title=Instructional Design: International Perspectives. Theory, research, and models. Vol. 1|last1=Tennyson|first1=Robert|last2=Dijkstra|first2=S.|last3=Schott|first3=Frank|last4=Seel|first4=Norbert|publisher=Lawrence Erlbaum Associates, Inc.|year=1997|isbn=0805814000|location=Mahwah, NJ|pages=42}}</ref> Specifically, they were linked to the training development model used by the [[United States Armed Forces|U.S. military]], which were based on systems approach and was explained as "the idea of viewing a problem or situation in its entirety with all its ramifications, with all its interior interactions, with all its exterior connections and with full cognizance of its place in its context."<ref>{{Cite book|title=Handbook of Improving Performance in the Workplace, Instructional Design and Training Delivery|last1=Silber|first1=Kenneth|last2=Foshay|first2=Wellesley|publisher=Pfeiffer|year=2010|isbn=9780470190685|location=San Francisco, CA|pages=62}}</ref>\n\nThe role of systems engineering in the early development of instructional design was demonstrated during [[World War II]] when a considerable amount of training materials for the military were developed based on the principles of instruction, learning, and human behavior. Tests for assessing a learner's abilities were used to screen candidates for the training programs. After the success of military training, psychologists began to view training as a system and developed various analysis, design, and evaluation procedures.<ref name="TrendsIssues" /> In 1946, [[Edgar Dale]] outlined a hierarchy of instructional methods, organized intuitively by their concreteness.<ref name="slides">Clark, B. (2009). ''[http://www.slideshare.net/benton44/history-of-instructional-design-and-technology?from=embed The history of instructional design and technology.] {{webarchive|url=https://web.archive.org/web/20121203232320/http://www.slideshare.net/benton44/history-of-instructional-design-and-technology?from=embed |date=2012-12-03 }}''</ref><ref>Thalheimer, Will. People remember 10%, 20%...Oh Really? October 8, 2006. {{cite web |url=http://www.willatworklearning.com/2006/10/people_remember.html |title=Archived copy |access-date=2016-09-15 |url-status=dead |archive-url=https://web.archive.org/web/20160914001649/http://www.willatworklearning.com/2006/10/people_remember.html |archive-date=2016-09-14 }}</ref> The framework first migrated to the industrial sector to train workers before it finally found its way to the education field.<ref>{{Cite book|title=Instructional Design: Principles and Applications|last1=Briggs|first1=Leslie|last2=Gustafson|first2=Kent|last3=Tillman|first3=Murray|publisher=Educational Technology Publications|year=1991|isbn=9780877782308|location=Englewood Cliffs, NJ|pages=375}}</ref>\n\n [[File:Bloom_taxonomy.svg|thumb|The original version of [[Bloom's taxonomy]] (published in 1956) defined a [[Bloom's taxonomy#The cognitive domain (knowledge-based)|cognitive domain]] in terms of six objectives.]]\n\nB. F. Skinner's 1954 article \u201c''The Science of Learning and the Art of Teaching''\u201d suggested that effective instructional materials, called programmed instructional materials, should include small steps, frequent questions, and immediate feedback; and should allow self-pacing.<ref name="TrendsIssues" /> [[Robert F. Mager]] popularized the use of learning objectives with his 1962 article \u201c''Preparing Objectives for Programmed Instruction\u201d''. The article describes how to write objectives including desired behavior, learning condition, and assessment.<ref name="TrendsIssues" />\n\nIn 1956, a committee led by [[Benjamin Bloom]] published an influential [[Taxonomy of Educational Objectives|taxonomy]] with three domains of learning: cognitive (what one knows or thinks), psychomotor (what one does, physically) and [[affective]] (what one feels, or what [[Attitude (psychology)|attitudes]] one has). These taxonomies still influence the design of instruction.<ref name="slides" /><ref>Bloom's Taxonomy. Retrieved from Wikipedia on April 18, 2012 at [[Bloom's Taxonomy]]</ref>\n\n [[Robert Glaser]] introduced \u201ccriterion-referenced measures\u201d in 1962. In contrast to norm-referenced tests in which an individual's performance is compared to group performance, a criterion-referenced test is designed to test an individual's behavior in relation to an objective standard. It can be used to assess the learners\u2019 entry level behavior, and to what extent learners have developed mastery through an instructional program.<ref name="TrendsIssues" />\n\nIn 1965, Robert Gagn\u00e9 (see below for more information) described three domains of learning outcomes (cognitive, affective, psychomotor), five learning outcomes (Verbal Information, Intellectual Skills, Cognitive Strategy, Attitude, Motor Skills), and nine events of instruction in \u201c''The Conditions of Learning''\u201d, which remain foundations of instructional design practices.<ref name="TrendsIssues" /> Gagne's work in learning hierarchies and hierarchical analysis led to an important notion in instruction \u2013 to ensure that learners acquire prerequisite skills before attempting superordinate ones.<ref name="TrendsIssues" />\n\nIn 1967, after analyzing the failure of training material, Michael Scriven suggested the need for formative assessment \u2013 e.g., to try out instructional materials with learners (and revise accordingly) before declaring them finalized.<ref name="TrendsIssues" />\n\n During the 1970s, the number of instructional design models greatly increased and prospered in different sectors in military, academia, and industry.<ref name="TrendsIssues" /> Many instructional design theorists began to adopt an information-processing-based approach to the design of instruction. David Merrill for instance developed Component Display Theory (CDT), which concentrates on the means of presenting instructional materials (presentation techniques).<ref>[http://www.instructionaldesign.org/theories/component-display.html Instructional Design Theories] {{webarchive|url=https://web.archive.org/web/20111004194825/http://www.instructionaldesign.org/theories/component-display.html |date=2011-10-04 }}. Instructionaldesign.org. Retrieved on 2011-10-07.</ref>\n\n Although interest in instructional design continued to be strong in business and the military, there was little evolution of ID in schools or higher education.<ref name="TrendsIssues" /><ref name="ReiserPDF">Reiser, R. A. (2001). "[https://files.nyu.edu/jpd247/public/2251/readings/Reiser_2001_History_of_ID.pdf A History of Instructional Design and Technology: Part II: A History of Instructional Design] {{webarchive|url=https://web.archive.org/web/20120915184958/https://files.nyu.edu/jpd247/public/2251/readings/Reiser_2001_History_of_ID.pdf |date=2012-09-15 }}". ETR&D, Vol. 49, No. 2, 2001, pp. 57\u201367.</ref>\nHowever, educators and researchers began to consider how the personal computer could be used in a [[learning environment]] or a [[learning space]].<ref name="TrendsIssues" /><ref name="slides" /><ref name="YouTube">History of instructional media. Uploaded to YouTube by crozitis on Jan 17, 2010. Retrieved from {{cite web |url=https://www.youtube.com/watch?v=y-fKcf4GuOU |title=Archived copy |website=[[YouTube]] |access-date=2016-12-01 |url-status=live |archive-url=https://web.archive.org/web/20170215093134/https://www.youtube.com/watch?v=y-fKcf4GuOU |archive-date=2017-02-15 }}</ref> [[PLATO (computer system)|PLATO]] (Programmed Logic for Automatic Teaching Operation) is one example of how computers began to be integrated into instruction.<ref name="HyperHist">[http://faculty.coe.uh.edu/smcneil/cuin6373/idhistory/index.html A hypertext history of instructional design] {{webarchive|url=https://web.archive.org/web/20120418193147/http://faculty.coe.uh.edu/smcneil/cuin6373/idhistory/index.html |date=2012-04-18 }}. Retrieved April 11, 2012</ref> Many of the first uses of computers in the classroom were for "drill and skill" exercises.<ref name="Markham">Markham, R. "[http://home.utah.edu/~rgm15a60/Paper/html/index_files/Page1108.htm History of instructional design] {{webarchive|url=https://web.archive.org/web/20130228081307/http://home.utah.edu/~rgm15a60/Paper/html/index_files/Page1108.htm |date=2013-02-28 }}". Retrieved on April 11, 2012</ref> There was a growing interest in how cognitive psychology could be applied to instructional design.<ref name="slides" />\n\n The influence of [[constructivism (philosophy of education)|constructivist theory]] on instructional design became more prominent in the 1990s as a counterpoint to the more traditional cognitive learning theory.<ref name="ReiserPDF" /><ref name="History">[http://www.instructionaldesigncentral.com/htm/IDC_instructionaltechnologytimeline.htm History and timeline of instructional design] {{webarchive|url=https://web.archive.org/web/20120425142515/http://www.instructionaldesigncentral.com/htm/IDC_instructionaltechnologytimeline.htm |date=2012-04-25 }}. Retrieved April 11, 2012</ref> Constructivists believe that learning experiences should be "authentic" and produce real-world learning environments that allow learners to construct their own knowledge.<ref name="ReiserPDF" /> This emphasis on the learner was a significant departure away from traditional forms of instructional design.<ref name="TrendsIssues" /><ref name="slides" /><ref name="History" />\n\n[[Performance improvement]] was also seen as an important outcome of learning that needed to be considered during the design process.<ref name="TrendsIssues" /><ref name="YouTube" /> The World Wide Web emerged as an online learning tool with [[hypertext]] and hypermedia being recognized as good tools for learning.<ref name="HyperHist" /> As technology advanced and constructivist theory gained popularity, technology's use in the classroom began to evolve from mostly drill and skill exercises to more interactive activities that required more complex thinking on the part of the learner.<ref name="Markham" /> Rapid prototyping was first seen during the 1990s. In this process, an instructional design project is prototyped quickly and then vetted through a series of try and revise cycles. This is a big departure from traditional methods of instructional design that took far longer to complete.<ref name="ReiserPDF" />\n\n Online learning became common.<ref name="TrendsIssues" /><ref name="Braine">Braine, B., (2010). "Historical Evolution of Instructional Design & Technology". Retrieved on April 11, 2012 from {{cite web |url=http://timerime.com/en/timeline/415929/Historical+Evolution+of+Instructional+Design++Technology/ |title=Archived copy |access-date=2012-04-14 |url-status=dead |archive-url=https://web.archive.org/web/20120526113721/http://timerime.com/en/timeline/415929/Historical+Evolution+of+Instructional+Design++Technology/ |archive-date=2012-05-26 }}</ref><ref>{{Cite web|url=http://www.xterior-windschermen.nl/|title=Xterior - Windschermen, Windschermen|last=Webbees|website=www.xterior-windschermen.nl|access-date=2016-11-05|url-status=live|archive-url=https://web.archive.org/web/20161024043905/http://www.xterior-windschermen.nl/|archive-date=2016-10-24}}</ref><ref>Trentin G. (2001). Designing Online Courses. In C.D. Maddux & D. LaMont Johnson (Eds) [https://www.researchgate.net/publication/235938996_Designing_Online_Courses?ev=pub_srch_pub The Web in Higher Education: Assessing the Impact and Fulfilling the Potential] {{webarchive|url=https://web.archive.org/web/20140505011040/http://www.researchgate.net/publication/235938996_Designing_Online_Courses?ev=pub_srch_pub |date=2014-05-05 }}, pp. 47-66, The Haworth Press Inc., New York, London, Oxford, {{ISBN|0-7890-1706-7}}.</ref> Technology advances permitted sophisticated simulations with authentic and realistic learning experiences.<ref name="Markham" />\n\nIn 2008, the Association for Educational Communications and Technology (AECT) changed the definition of Educational Technology to "the study and ethical practice of facilitating learning and improving performance by creating, using, and managing appropriate technological processes and resources".<ref>Association for Educational Communications and Technology (2008). Definition. In A. Januszewski and M. Molenda (Eds.), ''Educational Technology: A definition with commentary.'' New York: Lawrence Erlbaum Associates.</ref><ref>{{Cite journal|last1=Hlynka|first1=Denis|last2=Jacobsen|first2=Michele|date=2009|title=What is educational technology, anyway? A commentary on the new AECT definition of the field|url=https://www.cjlt.ca/index.php/cjlt/article/view/26395|journal=Canadian Journal of Learning and Technology|language=en|volume=35|issue=2|issn=1499-6685|url-status=live|archive-url=https://web.archive.org/web/20170904155646/https://www.cjlt.ca/index.php/cjlt/article/view/26395|archive-date=2017-09-04}}</ref>\n\n Academic degrees focused on integrating technology, internet, and [[human\u2013computer interaction]] with education gained momentum with the introduction of Learning Design and Technology (LDT) majors.  Universities such as [[Bowling Green State University]],<ref>{{cite web |url=http://www.bgsu.edu/technology-architecture-and-applied-engineering/departments-and-programs/visual-communication-and-technology-education/learning-design-and-technology.html |title=Archived copy |access-date=2016-08-03 |url-status=dead |archive-url=https://web.archive.org/web/20160805142032/http://www.bgsu.edu/technology-architecture-and-applied-engineering/departments-and-programs/visual-communication-and-technology-education/learning-design-and-technology.html |archive-date=2016-08-05 }} BGSU LDT</ref> [[Penn State]],<ref>{{cite web |url=http://ed.psu.edu/lps/ldt |title=Archived copy |access-date=2016-08-03 |url-status=live |archive-url=https://web.archive.org/web/20160723110536/http://ed.psu.edu/lps/ldt/ |archive-date=2016-07-23 }} Penn State LDT</ref> [[Purdue]],<ref>{{cite web |url=http://online.purdue.edu/ldt/learning-design-technology |title=Archived copy |access-date=2016-08-03 |url-status=live |archive-url=https://web.archive.org/web/20160803073738/http://online.purdue.edu/ldt/learning-design-technology |archive-date=2016-08-03 }} Purdue LDT</ref> [[San Diego State University]],<ref>{{cite web |url=http://jms.sdsu.edu/index.php/admissions/ldt_admissions_requirements |title=Archived copy |access-date=2016-08-03 |url-status=live |archive-url=https://web.archive.org/web/20160817222104/http://jms.sdsu.edu/index.php/admissions/ldt_admissions_requirements |archive-date=2016-08-17 }} SDSU LDT</ref> [[Stanford University|Stanford]], [[Harvard Graduate School of Education|Harvard]]<ref>{{cite web |url=https://ed.stanford.edu/academics/masters-handbook/program-requirements/ldt |title=Archived copy |access-date=2016-08-03 |url-status=live |archive-url=https://web.archive.org/web/20160819014703/https://ed.stanford.edu/academics/masters-handbook/program-requirements/ldt |archive-date=2016-08-19 }} Stanford LDT</ref> [[University of Georgia]],<ref>{{cite web |url=https://coe.uga.edu/academics/degrees/med/learning-design-technology |title=Archived copy |access-date=2016-08-03 |url-status=dead |archive-url=https://web.archive.org/web/20160901133238/https://coe.uga.edu/academics/degrees/med/learning-design-technology |archive-date=2016-09-01 }} UGA LDT</ref> California State University, Fullerton and [[Carnegie Mellon University]]<ref>{{cite web|url=http://metals.hcii.cmu.edu|title=METALS \u2013 Master of Educational Technology and Applied Learning Science @ Carnegie Mellon|website=metals.hcii.cmu.edu|url-status=live|archive-url=https://web.archive.org/web/20170401210608/http://metals.hcii.cmu.edu/|archive-date=2017-04-01}}</ref> have established undergraduate and graduate degrees in technology-centered methods of designing and delivering education.\n\nInformal learning became an area of growing importance in instructional design, particularly in the workplace.<ref name=":1">{{Cite news|url=http://cyrilandersontraining.com/2014/05/05/instructional-design-and-technical-writing/|title=Instructional Design and Technical Writing|date=2014-05-05|work=Cyril Anderson's Learning and Performance Support Blog|access-date=2018-11-29|language=en-US}}</ref><ref name=":2">{{Cite news|url=https://702010institute.com/informal-learning-important-formal-learning-moving-forward-702010/|title=Informal learning is more important than formal learning \u2013 moving forward with 70:20:10 - 70:20:10 Institute|date=2016-10-03|work=70:20:10 Institute|access-date=2018-11-29|language=en-US}}</ref> A 2014 study showed that formal training makes up only 4 percent of the 505 hours per year an average employee spends learning. It also found that the learning output of informal learning is equal to that of formal training.<ref name=":2" /> As a result of this and other research, more emphasis was placed on creating knowledge bases and other supports for self-directed learning.<ref name=":1" />", "Instructional design --- Introduction ---|Instructional Design history": "{| class="wikitable"\n|+ Instructional Media History<ref name="TrendsIssues"/>\n|-\n! Era!!  Media !!Characteristics  !! Outcome \n|-\n| 1900s ||Visual media || School museum as supplementary material (First school museum opened in  St. Louis in 1905)|| Materials are viewed as supplementary curriculum materials. District-wide media center is the modern equivalent.\n|-\n|  1914-1923||Visual media films, Slides, Photographer ||Visual Instruction Movement|| The effect of visual instruction was limited because of teacher resistance to change, quality of the file and cost etc.\n|-\n| Mid 1920s to 1930s || Radio broadcasting, Sound recordings, Sound motion pictures ||  Radio Audiovisual Instruction movement|| Education in large was not affected.\n|-\n|  World War II ||Training films, Overhead projector, Slide projector, Audio equipment, Simulators and training devices ||  Military and industry at this time had strong demand for training. || Growth of audio-visual instruction movement in school was slow, but audiovisual device were used extensively in military services and industry.\n|-\n|  Post World War II || Communication medium  ||Suggested to consider all aspects of a communication process (influenced by communication theories).  || This view point was first ignored, but eventually helped to expand the focus of the audiovisual movement.\n|-\n|  1950s to mid-1960s || Television  || Growth of Instructional television  || Instructional television was not adopted to a greater extent.\n|-\n|  1950s-1990s || Computer ||Computer-assisted instruction (CAI) research started in the 1950s, became popular in the 1980s a few years after computers became available to general  public. || The effect of CAI was rather small and the use of computer was far from innovative.\n|-\n|  1990s-2000s || Internet, Simulation ||The internet offered opportunities to train many people long distances. Desktop simulation gave advent to levels of Interactive Multimedia Instruction (IMI).  || Online training increased rapidly to the point where entire curriculums were given through web-based training.  Simulations are valuable but expensive, with the highest level being used primarily by the military and medical community. \n|-\n|  2000s-2020s || Mobile Devices, Social Media||On-demand training moved to people's personal devices; social media allowed for collaborative learning. Smartphones allowed for real-time interactive feedback. || Personalized learning paths enhanced by artificial intelligence. Microlearning and gamification are widely adopted to deliver learning in the flow of work. Real-time data capture enables ongoing design and remediation. \n\n|}"}},
{"article_title": "Webcam", "pageid": "92171", "revid": "1062395201", "timestamp": "2021-12-28T05:58:05Z", "history_paths": [["Webcam --- Introduction ---", "History"]], "categories": ["computing input devices", "english inventions", "film and video technology", "privacy", "teleconferencing", "videotelephony", "webcams", "world wide web", "articles containing video clips"], "heading_tree": {"Webcam --- Introduction ---": {"Technology": {"Image sensor": {}, "Optics": {}, "Compression": {}, "Interface": {}, "Software": {}}, "Characteristics": {}, "Uses": {"Video monitoring": {}, "Commerce": {}, "Videocalling and videoconferencing": {}, "Video security": {}, "Video clips and stills": {}, "Input control devices": {}, "Astro photography": {}, "Laser beam profiling": {}}, "History": {"Early development (Early 1990s)": {"IndyCam": {}}, "Commercial webcam (Mid 90s)": {"Connectix QuickCam": {}, "RS/6000 integrated webcam": {}}, "Entering the mainstream (Late 90s - 2000s)": {}, "Later developments (2010s - Present)": {}}, "Privacy": {}, "Effects on modern society": {}, "Descriptive names and terminology": {}, "See also": {}, "References": {}, "Bibliography": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Webcam --- Introduction ---|History": "{{See also|History of videotelephony}}\n\n First developed in 1991, a webcam was pointed at the [[Trojan Room coffee pot]] in the [[University of Cambridge|Cambridge University]] Computer Science Department (initially operating over a local network instead of the web). The camera was finally switched off on August 22, 2001. The final image captured by the camera can still be viewed at its homepage.<ref>[http://www.cl.cam.ac.uk/coffee/coffee.html CoffeeCam] {{Webarchive|url=https://www.webcitation.org/6688onux5?url=http://www.cl.cam.ac.uk/coffee/coffee.html |date=2012-03-13 }}, University of Cambridge.</ref><ref>{{cite web|url=http://www.spiegel.de/static/popup/coffeecam/cam2.html|title=Trojan Room Coffee Pot \u2013 SPIEGEL ONLINE|access-date=29 July 2015|archive-url=https://web.archive.org/web/20150925043554/http://www.spiegel.de/static/popup/coffeecam/cam2.html|archive-date=25 September 2015|url-status=live}}</ref> The oldest continuously operating webcam, [[San Francisco State University]]'s FogCam, has run since 1994 and was slated to turn off August 2019.<ref>{{cite web |title='World's oldest webcam' to be switched off |url=https://www.bbc.co.uk/news/technology-49408335 |website=BBC News |access-date=20 August 2019 |date=20 August 2019 |archive-url=https://web.archive.org/web/20190820170350/https://www.bbc.co.uk/news/technology-49408335 |archive-date=20 August 2019 |url-status=live }}</ref> After the publicity following extensive news coverage about the planned ending of FogCam, SFSU agreed to continue maintaining the FogCam and keep it running.<ref>{{cite web |title=FogCam on Twitter |url=https://twitter.com/FogCam  }}</ref><ref>{{cite web |title=FogCam.org |url=https://FogCam.org  }}</ref>\n[[File:Silicon Graphics camera IMG 4205.jpg|thumb|[[Silicon Graphics|SGI]] IndyCam]]\n\n The released in 1993 [[SGI Indy]] is the first commercial computer to have a standard video camera,<ref name="MD camera">{{cite magazine|date=August 13, 1993|title=Low-cost, high-speed SGI Indy comes with camera|url=https://search.proquest.com/docview/217148786|magazine=Machine Design|volume=65|issue=16|page=84|id={{ProQuest|217148786}}|access-date=March 5, 2021|via=[[ProQuest]]|url-access=registration}}</ref> and the first SGI computer to have standard video inputs.<ref name="ED Video input">{{cite magazine|author=DB|date=July 22, 1993|title=Video input becoming workstation standard.|url=https://web-b-ebscohost-com.wikipedialibrary.idm.oclc.org/ehost/detail/detail?vid=0&sid=d6805b5a-27de-4991-a527-b8d1649e6b8e%40pdc-v-sessmgr01&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=9311156271&db=f6h|magazine=Electronic Design|volume=41|issue=15|page=30|issn=0013-4872|access-date=March 5, 2021|via=[[EBSCO]]|url-access=registration}}</ref>\n\nThe maximum supported input resolution is 640\u00d7480 for [[NTSC]] or 768\u00d7576 for [[PAL]]. A fast machine is required to capture at either of these resolutions, though; an Indy with slower [[R4600|R4600PC]] CPU, for example, may require the input resolution to be reduced before storage or processing.  However, the Vino hardware is capable of [[Direct memory access|DMA]]ing video fields directly into the framebuffer with minimal CPU overhead.\n\n \n The first widespread commercial webcam, the black-and-white [[QuickCam]], entered the marketplace in 1994, created by the U.S. computer company [[Connectix]]. QuickCam was available in August 1994 for the [[Apple Macintosh]], connecting via a [[serial port]], at a cost of $100.  Jon Garber, the designer of the device, had wanted to call it the "Mac-camera", but was overruled by Connectix's marketing department; a version with a PC-compatible parallel port and software for  [[Microsoft Windows]] was launched in October 1995.  The original QuickCam provided 320x240-pixel resolution with a grayscale depth of 16 shades at 60 frames per second, or 256 shades at 15 frames per second.<ref>Edwards, Benj. [http://www.pcworld.com/article/199112/victorian_scifi.html History of Video Calls: From Fantasy to Flops to Facetime] {{Webarchive|url=https://web.archive.org/web/20111010182111/http://www.pcworld.com/article/199112/victorian_scifi.html |date=2011-10-10 }}, [[PC World (magazine)|PC World Magazine]], June 17, 2010.</ref>  These cam were tested on several Delta II launch using a variety of communication protocols including CDMA, TDMA, GSM and HF.\n\nIn 2010, [[Time Magazine]] named the QuickCam as one of the top computer devices of all time.<ref>Ha, Peter. [http://www.time.com/time/specials/packages/article/0,28804,2023689_2023703_2023628,00.html Computing: Connectix QuickCam] {{Webarchive|url=https://web.archive.org/web/20110120104554/http://www.time.com/time/specials/packages/article/0,28804,2023689_2023703_2023628,00.html |date=2011-01-20 }}, [[Time Magazine]], October 25, 2010.</ref>\n\n[[Videoconferencing]] via computers already existed, and at the time [[Client\u2013server model|client-server]] based videoconferencing software such as [[CU-SeeMe]] had started to become popular.\n\n The first widely known laptop with integrated webcam option, at a pricepoint starting at US$ 12,000, was an IBM [[RS/6000]] 860 laptop<ref>{{cite web|url=http://ps-2.kev009.com/aixtp/Brochure/4249-860.pdf|title=RS/6000 Notebook 860|website=kev009.com}}</ref><ref>{{Cite web|date=2000-06-28|title=US - IBM RS/6000 Notebook 860 Model 860|url=https://www-01.ibm.com/common/ssi/rep_sm/0/897/ENUS7249-860/index.html|access-date=2020-12-30|website=www-01.ibm.com|language=en-US}}</ref> and his [[ThinkPad 850]] sibling,<ref>{{Cite web|date=1996-07-09|title=IBM ThinkPad Power Series 820 and 850|url=https://www-01.ibm.com/common/ssi/printableversion.wss?docURL=/common/ssi/rep_ca/8/877/ENUSZG96-0188/index.html&request_locale=en|access-date=2020-12-30|website=www-01.ibm.com|language=en-US}}</ref> released in 1996.\n\n One of the most widely reported-on webcam sites was [[JenniCam]], created in 1996, which allowed Internet users to observe the life of its namesake constantly, in the same vein as the [[Reality television|reality TV series]] ''[[Big Brother (TV series)|Big Brother]]'', launched four years later.<ref>[https://www.theguardian.com/international/story/0,,1115262,00.html "Plug pulled on live website seen by millions"] by Oliver Burkeman in ''The Guardian'', January 3, 2004</ref>  Other cameras are mounted overlooking bridges, public squares, and other public places, their output made available on a public web page in accordance with the original concept of a "webcam".  Aggregator websites have also been created, providing thousands of live video streams or up-to-date still pictures, allowing users to find live video streams based on location or other criteria.\n\nIn the late 1990s, [[Microsoft NetMeeting]] was the only videoconferencing software on PC in widespread use, making use of webcams.<ref>{{Cite web|url=https://www.chicagotribune.com/news/ct-xpm-1999-05-24-9905240145-story.html|title=Video-Conference Program Allows More Private Face-To-Face Time|website=[[Chicago Tribune]]}}</ref> In the following years, [[instant messaging]] clients started adding webcam support: [[Yahoo Messenger]] introduced this with version 5.5 in 2002, allowing video calling in 20 frames per second using a webcam.<ref>{{Cite web|url=https://www.computerweekly.com/news/2240047061/Yahoo-instant-messenger-unveils-broadband-Webcam|title = Yahoo! Instant messenger unveils broadband Webcam}}</ref> [[MSN Messenger]] gained this in version 5.0 in 2003.<ref>{{Cite web|url=https://www.computerweekly.com/news/2240049915/MSN-Messenger-gains-webcam-functionality|title=MSN Messenger gains webcam functionality}}</ref>\n\nAround the turn of the 21st century, computer hardware manufacturers began building webcams directly into [[laptop]] and desktop screens, thus eliminating the need to use an external USB or [[FireWire]] camera.  Gradually webcams came to be used more for telecommunications, or [[videotelephony]], between two people, or among several people, than for offering a view on a Web page to an unknown public.\n\n For less than US$100 in 2012, a [[three-dimensional|three-dimensional space]] webcam became available, producing videos and photos in 3D [[anaglyph image]] with a resolution up to 1280 \u00d7 480 pixels. Both sender and receiver of the images must use 3D glasses to see the effect of three dimensional image.<ref>{{cite web |last=Lanxon |first=Nate |url=http://crave.cnet.co.uk/gadgets/3d-photos-minoru-3d-webcam-hands-on-49303012/ |title=3D photos: Minoru 3D webcam hands-on | CNET UK |publisher=Crave.cnet.co.uk |date=2009-07-16 |access-date=2013-01-07 |archive-url=https://web.archive.org/web/20101205030408/http://crave.cnet.co.uk/gadgets/3d-photos-minoru-3d-webcam-hands-on-49303012/ |archive-date=2010-12-05 |url-status=dead }}</ref>\n\nWebcams are considered an essential accessory for working from home, mainly to compensate for lower quality video processing with the built-in camera of the average laptop. As a result of the COVID-19 pandemic, webcams initially sold out, or their prices were being marked up by third party sellers.<ref>{{Cite web|url=https://www.theverge.com/2020/4/9/21199521/webcam-shortage-price-raise-logitech-razer-amazon-best-buy-ebay|title = Webcams have become impossible to find, and prices are skyrocketing|date = 9 April 2020}}</ref> Most laptops before and during the pandemic were made with cameras capping out at 720p recording quality at best, compared to the industry standard of 1080p or 4K seen in smartphones and televisions from the same period.<ref>{{Cite web|url=https://www.techradar.com/news/computing-components/peripherals/what-webcam-5-reviewed-and-rated-1027972|title = Best webcams 2021: Top picks for working from home|date = 5 August 2021}}</ref> The backlog on new developments for built-in webcams is the result of a design flaw with laptops being too thin to support the 7mm camera modules to fit inside, instead resorting to ~2.5mm.<ref>{{Cite web|url=https://www.theverge.com/2018/2/25/17050098/huawei-matebook-x-pro-webcam-mwc-2018|title=Huawei's new laptop has a mechanical pop-up webcam in the keyboard|date=25 February 2018}}</ref><ref>{{Cite web|url=https://www.digitaltrends.com/computing/laptops-need-better-webcams/|title = In the Age of Zoom, Bad Laptop Webcams Are a Big Problem|date = 8 April 2020}}</ref> Also the camera components are more expensive and not a high level of demand for this feature, companies like Apple have not updated their webcams since 2012.<ref>{{Cite web|url=https://www.imore.com/macbook-air-2020-so-much-love-except-crappy-facetime-camera|title=Dear Apple, please stop putting crummy cameras on your MacBooks|date=19 March 2020}}</ref> Smartphones started to be used as a backup option or webcam replacement, with kits including lighting and tripods or downloadable apps.<ref>{{Cite magazine|url=https://www.wired.com/story/use-your-phone-as-webcam/|title = How to Turn Your Smartphone into a Webcam|magazine = Wired}}</ref>"}},
{"article_title": "Agricultural biotechnology", "pageid": "93829", "revid": "1058152097", "timestamp": "2021-12-01T19:59:05Z", "history_paths": [["Agricultural biotechnology --- Introduction ---", "History"]], "categories": ["agricultural technology", "biotechnology", "life sciences industry"], "heading_tree": {"Agricultural biotechnology --- Introduction ---": {"History": {}, "Crop modification techniques": {"Traditional breeding": {}, "Mutagenesis": {}, "Polyploidy": {}, "Protoplast fusion": {}, "RNA interference": {}, "Transgenics": {}, "Genome editing": {}}, "Improved nutritional content": {}, "Genes and traits of interest for crops": {"Agronomic traits": {"Insect resistance": {}, "Herbicide tolerance": {}, "Disease resistance": {}, "Temperature tolerance": {}}, "Quality traits": {}}, "Common GMO crops": {}, "Safety testing and government regulations": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Agricultural biotechnology --- Introduction ---|History": "[[Farmer|Farmers]] have manipulated plants and animals through [[selective breeding]] for decades of thousands of years in order to create desired traits. In the 20th century, a surge in technology resulted in an increase in agricultural biotechnology through the selection of traits like the increased yield, pest resistance, [[drought resistance]], and herbicide resistance. The first food product produced through [[biotechnology]] was sold in 1990, and by 2003, 7 million farmers were utilizing biotech crops. More than 85% of these farmers were located in developing countries.<ref>{{Cite web|url=http://absp2.cornell.edu/resources/briefs/documents/warp_briefs_eng_scr.pdf|title=Agricultural Biotechnology|date=2004|website=cornell.edu|publisher=PBS, ABSP II, US Agency for International Development|access-date=1 Dec 2016}}</ref>"}},
{"article_title": "Nuclear technology", "pageid": "97830", "revid": "1054221196", "timestamp": "2021-11-08T19:42:02Z", "history_paths": [["Nuclear technology --- Introduction ---", "History and scientific background"]], "categories": ["nuclear technology"], "heading_tree": {"Nuclear technology --- Introduction ---": {"History and scientific background": {"Discovery": {}, "Nuclear fission": {}, "Nuclear fusion": {}}, "Nuclear weapons": {}, "Civilian uses": {"Nuclear power": {}, "Medical applications": {}, "Industrial applications": {}, "Commercial applications": {}, "Food processing and agriculture": {}}, "Accidents": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Nuclear technology --- Introduction ---|History and scientific background": "{{main|Nuclear physics}}\nThe vast majority of common, natural phenomena on Earth only involve [[gravity]] and [[electromagnetism]], and not nuclear reactions. This is because atomic nuclei are generally kept apart because they contain positive electrical charges and therefore repel each other.\n\nIn 1896, [[Henri Becquerel]] was investigating [[phosphorescence]] in [[uranium]] salts when he discovered a new phenomenon which came to be called [[radioactivity]].<ref>{{cite web|url=http://nobelprize.org/nobel_prizes/physics/laureates/1903/becquerel-bio.html|title=Henri Becquerel - Biographical|website=nobelprize.org|access-date=9 May 2018|url-status=live|archive-url=https://web.archive.org/web/20170904065620/https://www.nobelprize.org/nobel_prizes/physics/laureates/1903/becquerel-bio.html|archive-date=4 September 2017}}</ref> He, [[Pierre Curie]] and [[Marie Curie]] began investigating the phenomenon. In the process, they isolated the element [[radium]], which is highly radioactive. They discovered that radioactive materials produce intense, penetrating rays of three distinct sorts, which they labeled alpha, beta, and gamma after the first three [[Greek alphabet|Greek letters]]. Some of these kinds of radiation could pass through ordinary matter, and all of them could be harmful in large amounts. All of the early researchers received various [[radiation burn]]s, much like [[sunburn]], and thought little of it.\n\nThe new phenomenon of radioactivity was seized upon by the manufacturers of [[quack medicine]] (as had the discoveries of [[electricity]] and [[magnetism]], earlier), and a number of [[patent medicine]]s and treatments involving radioactivity were put forward.\n\nGradually it was realized that the radiation produced by radioactive decay was [[ionizing radiation]], and that even quantities too small to burn could pose a [[nuclear safety|severe long-term hazard]]. Many of the scientists working on radioactivity died of [[cancer]] as a result of their exposure. Radioactive patent medicines mostly disappeared, but other applications of radioactive materials persisted, such as the use of radium salts to produce [[Radium Girls|glowing dials on meters]].\n\nAs the atom came to be better understood, the nature of radioactivity became clearer. Some larger atomic nuclei are unstable, and so [[radioactive decay|decay]] (release matter or energy) after a random interval. The three forms of [[Ionizing radiation|radiation]] that Becquerel and the Curies discovered are also more fully understood. [[Alpha decay]] is when a nucleus releases an [[alpha particle]], which is two [[proton]]s and two [[neutron]]s, equivalent to a [[helium]] nucleus. [[Beta decay]] is the release of a [[beta particle]], a high-energy [[electron]]. [[Gamma decay]] releases [[gamma rays]], which unlike alpha and beta radiation are not matter but [[electromagnetic radiation]] of very high [[frequency]], and therefore [[energy]]. This type of radiation is the most dangerous and most difficult to block. All three types of radiation occur naturally in [[List of elements by stability of isotopes|certain elements]].\n\nIt has also become clear that the ultimate source of most terrestrial energy is nuclear, either through radiation from the [[Sun]] caused by [[Stellar surface fusion|stellar thermonuclear reactions]] or by radioactive decay of uranium within the Earth, the principal source of [[geothermal energy]].\n\n {{main|Nuclear fission}}\nIn natural nuclear radiation, the byproducts are very small compared to the nuclei from which they originate. Nuclear fission is the process of splitting a nucleus into roughly equal parts, and releasing energy and neutrons in the process. If these neutrons are captured by another unstable nucleus, they can fission as well, leading to a [[chain reaction]]. The average number of neutrons released per nucleus that go on to fission another nucleus is referred to as ''k''. Values of ''k'' larger than 1 mean that the fission reaction is releasing more neutrons than it absorbs, and therefore is referred to as a self-sustaining chain reaction. A mass of fissile material large enough (and in a suitable configuration) to induce a self-sustaining chain reaction is called a [[Critical mass (nuclear)|critical mass]].\n\nWhen a neutron is captured by a suitable nucleus, fission may occur immediately, or the nucleus may persist in an unstable state for a short time. If there are enough immediate decays to carry on the chain reaction, the mass is said to be [[Prompt criticality|prompt critical]], and the energy release will grow rapidly and uncontrollably, usually leading to an explosion.\n\nWhen discovered on the eve of [[World War II]], this insight led multiple countries to begin programs investigating the possibility of constructing an [[atomic bomb]] \u2014 a weapon which utilized fission reactions to generate far more energy than could be created with chemical explosives. The [[Manhattan Project]], run by the [[United States]] with the help of the [[United Kingdom]] and [[Canada]], developed multiple fission weapons which were used against [[Japan]] in 1945 at [[Hiroshima]] and [[Nagasaki]]. During the project, the first [[nuclear reactor|fission reactors]] were developed as well, though they were primarily for weapons manufacture and did not generate electricity.\n\nIn 1951, the first nuclear fission power plant was the first to produce electricity at the Experimental Breeder Reactor No. 1 (EBR-1), in Arco, Idaho, ushering in the "Atomic Age" of more intensive human energy use.<ref>{{cite web|url=https://futurism.com/images/a-brief-history-of-technology/|title=A Brief History of Technology|website=futurism.com|access-date=9 May 2018|url-status=live|archive-url=https://web.archive.org/web/20180423093858/https://futurism.com/images/a-brief-history-of-technology/|archive-date=23 April 2018}}</ref>\n\nHowever, if the mass is critical only when the delayed neutrons are included, then the reaction can be controlled, for example by the introduction or removal of [[neutron absorber]]s. This is what allows [[nuclear reactor]]s to be built. Fast neutrons are not easily captured by nuclei; they must be slowed (slow neutrons), generally by collision with the nuclei of a [[neutron moderator]], before they can be easily captured. Today, this type of fission is commonly used to generate electricity.\n\n {{main|Nuclear fusion}}\n{{see also|Timeline of nuclear fusion}}\nIf nuclei are forced to collide, they can undergo [[nuclear fusion]]. This process may release or absorb energy. When the resulting nucleus is lighter than that of [[iron]], energy is normally released; when the nucleus is heavier than that of iron, energy is generally absorbed. This process of fusion occurs in [[star]]s, which derive their energy from [[hydrogen]] and [[helium]]. They form, through [[stellar nucleosynthesis]], the light elements ([[lithium]] to [[calcium]]) as well as some of the heavy elements (beyond iron and [[nickel]], via the [[S-process]]). The remaining abundance of heavy elements, from nickel to uranium and beyond, is due to [[supernova nucleosynthesis]], the [[R-process]].\n\nOf course, these natural processes of astrophysics are not examples of nuclear "technology". Because of the very strong repulsion of nuclei, fusion is difficult to achieve in a controlled fashion. [[Hydrogen bomb]]s obtain their enormous destructive power from fusion, but their energy cannot be controlled. Controlled fusion is achieved in [[particle accelerator]]s; this is how many [[synthetic element]]s are produced. A [[fusor]] can also produce controlled fusion and is a useful [[neutron source]]. However, both of these devices operate at a net energy loss. Controlled, viable [[fusion power]] has proven elusive, despite the occasional [[cold fusion|hoax]]. Technical and theoretical difficulties have hindered the development of working civilian fusion technology, though research continues to this day around the world.\n\nNuclear fusion was initially pursued only in theoretical stages during World War II, when scientists on the Manhattan Project (led by [[Edward Teller]]) investigated it as a method to build a bomb. The project abandoned fusion after concluding that it would require a fission reaction to detonate. It took until 1952 for the first full [[hydrogen]] bomb to be detonated, so-called because it used reactions between [[deuterium]] and [[tritium]]. Fusion reactions are much more energetic per unit mass of [[Nuclear fuel|fuel]] than fission reactions, but starting the fusion chain reaction is much more difficult."}},
{"article_title": "Transcranial magnetic stimulation", "pageid": "98093", "revid": "1058819173", "timestamp": "2021-12-05T19:38:11Z", "history_paths": [["Transcranial magnetic stimulation --- Introduction ---", "History"]], "categories": ["physical psychiatric treatments", "electrotherapy", "magnetic devices", "neurophysiology", "neuropsychology", "neurotechnology", "treatment of bipolar disorder", "treatment of depression", "medical devices", "1985 introductions", "2008 introductions", "bioelectromagnetics"], "heading_tree": {"Transcranial magnetic stimulation --- Introduction ---": {"Medical uses": {"Diagnosis": {}, "Treatment": {}}, "Adverse effects": {}, "Procedure": {}, "Physics": {"Frequency and duration": {}, "Coil types": {}}, "History": {}, "Research": {"Study blinding": {}, "Animal model limitations": {}}, "Treatments for the general public": {"Regulatory approvals": {"Neurosurgery planning": {}, "Depression": {}, "Migraine": {}, "Other neurological areas": {}}, "Coverage by health services and insurers": {"United Kingdom": {}, "United States: Commercial health insurance": {}, "United States: Medicare": {}}, "Costs": {}, "Providers": {}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Transcranial magnetic stimulation --- Introduction ---|History": "[[Luigi Galvani]] (1737-1798) undertook research on the effects of electricity on the body in the late-eighteenth century and laid the foundations for the field of [[electrophysiology]].<ref name=Horvath>{{cite journal | vauthors = Horvath JC, Perez JM, Forrow L, Fregni F, Pascual-Leone A | title = Transcranial magnetic stimulation: a historical evaluation and future prognosis of therapeutically relevant ethical concerns | journal = Journal of Medical Ethics | volume = 37 | issue = 3 | pages = 137\u201343 | date = March 2011 | pmid = 21106996 | doi = 10.1136/jme.2010.039966 | jstor = 23034661 | s2cid = 13262044 }}</ref> In the 1830s [[Michael Faraday]] (1791-1867) discovered that an [[electrical current]] had a corresponding [[magnetic field]], and that changing one could induce its counterpart.<ref name=Nooh>{{cite journal | vauthors = Noohi S, Amirsalari S | title = History, Studies and Specific Uses of Repetitive Transcranial Magnetic Stimulation (rTMS) in Treating Epilepsy | journal = Iranian Journal of Child Neurology | volume = 10 | issue = 1 | pages = 1\u20138 | date = 2016 | pmid = 27057180 | pmc = 4815479 }}</ref>\n\nWork to directly stimulate the human brain with electricity started in the late 1800s, and by the 1930s the Italian physicians [[Ugo Cerletti|Cerletti]] and [[Lucio Bini|Bini]] had developed [[electroconvulsive therapy]] (ECT).<ref name=Horvath/> ECT became widely used to treat [[mental illness]], and ultimately overused, as it began to be seen as a [[panacea (medicine)|panacea]]. This led to a backlash in the 1970s.<ref name=Horvath/>\n\nIn 1980 Merton and Morton successfully used transcranial electrical stimulation (TES) to stimulate the motor cortex. However, this process was very uncomfortable, and subsequently Anthony T. Barker began to search for an alternative to TES.<ref>{{cite journal | vauthors = Klomjai W, Katz R, Lackmy-Vall\u00e9e A | title = Basic principles of transcranial magnetic stimulation (TMS) and repetitive TMS (rTMS) | journal = Annals of Physical and Rehabilitation Medicine | volume = 58 | issue = 4 | pages = 208\u2013213 | date = September 2015 | pmid = 26319963 | doi = 10.1016/j.rehab.2015.05.005 | doi-access = free }}</ref> He began exploring the use of magnetic fields to alter electrical signaling within the brain, and the first stable TMS devices were developed in 1985.<ref name=Horvath/><ref name=Nooh/> They were originally intended{{by whom|date=October 2019}} as diagnostic and research devices, with evaluation of their therapeutic potential being a later development.<ref name=Horvath/><ref name=Nooh/>  The United States' [[Food and Drug Administration|FDA]] first approved TMS devices in October 2008.<ref name=Horvath/>"}},
{"article_title": "Radio wave", "pageid": "98132", "revid": "1062110903", "timestamp": "2021-12-26T10:01:38Z", "history_paths": [["Radio wave --- Introduction ---", "Discovery and exploitation"]], "categories": ["radio technology", "waves", "electromagnetic spectrum"], "heading_tree": {"Radio wave --- Introduction ---": {"Discovery and exploitation": {}, "Generation and reception": {}, "Properties": {"Polarization": {}}, "Propagation characteristics": {}, "Radio communication": {}, "Biological and environmental effects": {}, "Measurement": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Radio wave --- Introduction ---|Discovery and exploitation": "{{Main|History of radio}}\nRadio waves were first predicted by mathematical work done in 1867 by Scottish mathematical physicist [[James Clerk Maxwell]].<ref name="Harman1998">{{cite book |last=Harman |first=Peter Michael |year=1998 |title=The natural philosophy of James Clerk Maxwell |publisher=Cambridge University Press |isbn=0-521-00585-X |location=Cambridge, UK |page=6}}</ref> His mathematical theory, now called [[Maxwell's equations]], predicted that a coupled [[electric field|electric]] and [[magnetic field]] could travel through space as an "[[electromagnetic wave]]". Maxwell proposed that light consisted of electromagnetic waves of very short wavelength. In 1887, German physicist [[Heinrich Hertz]] demonstrated the reality of Maxwell's electromagnetic waves by experimentally generating radio waves in his laboratory,<ref>{{cite web |last=Edwards|first=Stephen A. |title=Heinrich Hertz and electromagnetic radiation |url=https://www.aaas.org/heinrich-hertz-and-electromagnetic-radiation|access-date=13 April 2021|publisher=American Association for the Advancement of Science}}</ref> showing that they exhibited the same wave properties as light: [[standing wave]]s, [[refraction]], [[diffraction]], and [[polarization (waves)|polarization]]. Italian inventor [[Guglielmo Marconi]] developed the first practical radio transmitters and receivers around 1894\u20131895. He received the 1909 [[Nobel Prize in physics]] for his radio work. Radio communication began to be used commercially around 1900. The modern term "''radio wave''" replaced the original name "''Hertzian wave''" around 1912."}},
{"article_title": "High-temperature superconductivity", "pageid": "101336", "revid": "1062689193", "timestamp": "2021-12-29T23:27:23Z", "history_paths": [["High-temperature superconductivity --- Introduction ---", "History"]], "categories": ["high-temperature superconductors", "correlated electrons", "emerging technologies", "unsolved problems in physics"], "heading_tree": {"High-temperature superconductivity --- Introduction ---": {"History": {}, "Selected list of superconductors": {}, "Properties": {"Cuprates": {}, "Iron-based": {}, "Magnesium diboride": {}, "Nickelates": {"Magnetic properties": {}}}, "Cuprates": {"Yttrium\u2013barium cuprate": {}, "Other cuprates": {}, "Preparation and manufacturing": {}}, "Ongoing research": {}, "Theoretical models": {"D symmetry in YBCO": {}, "Spin-fluctuation mechanism": {}}, "Examples": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"High-temperature superconductivity --- Introduction ---|History": "[[File:Timeline of Superconductivity from 1900 to 2015.svg|thumb|462x462px|Timeline of superconductor discoveries. On the right one can see the liquid nitrogen temperature, which usually divides superconductors at high from superconductors at low temperatures. [[Cuprate]]s are displayed as blue diamonds, and [[iron-based superconductor]]s as yellow squares. [[Magnesium diboride]] and other low-temperature metallic [[BCS superconductor]]s are displayed for reference as green circles.]]\n\nSuperconductivity was discovered by [[Heike Kamerlingh Onnes|Kamerlingh Onnes]] in 1911, in a metal solid. Ever since, researchers have attempted to observe superconductivity at increasing temperatures<ref name="bbc">\n{{cite video\n |people=Nisbett, Alec (producer)\n |year=1988\n |title=Superconductor: The race for the prize\n |medium=Television Episode\n}}\n</ref> with the goal of finding a [[room-temperature superconductor]].<ref>\n{{cite book\n |last=Mourachkine  |first=A.\n |year=2004\n |title=Room-Temperature Superconductivity\n |publisher=Cambridge International Science Publishing\n |arxiv=cond-mat/0606187\n |place=Cambridge, UK\n |id=cond\u2013mat/0606187  |isbn=978-1-904602-27-9  |bibcode=2006cond.mat..6187M\n}}\n</ref> By the late 1970s, superconductivity was observed in several metallic compounds (in particular Nb-based, such as [[Niobium\u2013titanium|NbTi]], [[Niobium\u2013tin|Nb<sub>3</sub>Sn]], and [[Nb3Ge|Nb<sub>3</sub>Ge]]) at temperatures that were much higher than those for elemental metals and which could even exceed {{convert|20|K|C}}. \nIn 1986, at the [[IBM]] research lab near [[Zurich]], in [[Switzerland]], Bednorz and M\u00fcller were looking for superconductivity in a new class of '''[[ceramic]]s''': the ''copper oxides'', or ''cuprates''. \nBednorz encountered a particular '''copper oxide''' whose resistance dropped to zero at a temperature around {{convert|-238|C|K}}.<ref name=bbc/> Their results were soon confirmed<ref>\nStuart A Wolf & Vladimir Z Kresin, Eds, Novel Superconductivity, Springer (October 1987)\n</ref> by many groups, notably [[Chu Ching-wu|Paul Chu]] at the [[University of Houston]] and Shoji Tanaka at the [[University of Tokyo]].<ref name=tanaka01>\n{{cite journal\n |last=Tanaka |first=Shoji\n |title=High temperature superconductivity: History and Outlook\n |journal=JSAP International\n |year=2001\n |url=http://www.jsap.or.jp/jsapi/Pdf/Number04/PastPresentFuture.pdf\n |access-date=March 2, 2012  |url-status=live\n |archive-url=https://web.archive.org/web/20120816203010/http://www.jsap.or.jp/jsapi/Pdf/Number04/PastPresentFuture.pdf\n |archive-date=August 16, 2012\n}}\n</ref>\n\nShortly after, at [[Princeton University]], [[P. W. Anderson|Anderson]] gave the first theoretical description of these materials, based on the [[resonating valence bond theory]],<ref name=Anderson87>\n{{cite journal\n |last=Anderson |first=Philip\n |year=1987\n |title=The resonating valence bond state in la-2CuO-4 and superconductivity\n |journal=Science\n |volume=235 |issue=4793 |pages=1196\u20131198\n |bibcode=1987Sci...235.1196A |doi=10.1126/science.235.4793.1196\n |pmid=17818979 |s2cid=28146486\n}}\n</ref> but a full understanding of these materials is still developing today. These superconductors are now known to possess a ''d''-wave{{clarify|date=June 2014}} pair symmetry. The first proposal that high-temperature cuprate superconductivity involves ''d''-wave pairing was made in 1987 by Bickers, [[Douglas James Scalapino|Scalapino]] and Scalettar,<ref name=bickers87>\n{{cite journal\n |last1=Bickers    |first1=N.E.\n |last2=Scalapino  |first2=D.J.\n |last3=Scalettar  |first3=R.T.\n |year=1987\n |title=CDW and SDW mediated pairing interactions\n |journal=Int. J. Mod. Phys. B\n |volume=1  |issue=3n04  |pages=687\u2013695\n |bibcode=1987IJMPB...1..687B  |doi=10.1142/S0217979287001079\n}}\n</ref> followed by three subsequent theories in 1988 by Inui, Doniach, Hirschfeld and Ruckenstein,<ref name=inui88>\n{{cite journal |last1=Inui       |first1=Masahiko   |last2=Doniach     |first2=Sebastian |last3=Hirschfeld |first3=Peter J.   |last4=Ruckenstein |first4=Andrei E. |last5=Zhao       |first5=Z.         |last6=Yang        |first6=Q. |last7=Ni         |first7=Y.         |last8=Liu         |first8=G. |year=1988 |title=Coexistence of antiferromagnetism and superconductivity in a mean-field theory of high-{{mvar|T}}{{sub|c}} superconductors |journal=Phys. Rev. B |volume=37 |issue=10 |pages=5182\u20135185\n |bibcode=1988PhRvB..37.5182D  |doi=10.1103/PhysRevB.37.5182  |pmid=9943697 |url=http://prb.aps.org/abstract/PRB/v37/i4/p2320_1  |url-status=dead |archive-url=https://archive.today/20130703172401/http://prb.aps.org/abstract/PRB/v37/i4/p2320_1 |archive-date=July 3, 2013}}</ref> using spin-fluctuation theory, and by [[Claudius Gros|Gros]], Poilblanc, Rice and Zhang,<ref name=gros88>\n{{cite journal\n |last1=Gros   |first1=Claudius\n |last2=Poilblanc |first2=Didier\n |last3=Rice   |first3=T. Maurice\n |last4=Zhang  |first4=F. C.\n |year=1988\n |title=Superconductivity in correlated wavefunctions\n |journal=Physica C\n |volume=153\u2013155 |pages=543\u2013548\n |bibcode=1988PhyC..153..543G |doi=10.1016/0921-4534(88)90715-0\n}}</ref> and by [[Gabriel Kotliar|Kotliar]] and Liu identifying ''d''-wave pairing as a natural consequence of the RVB theory.<ref name=kotliar88>\n{{cite journal\n |last1=Kotliar |first1=Gabriel\n |last2=Liu     |first2=Jialin\n |year=1988\n |title=Superexchange mechanism and d-wave superconductivity\n |journal=Physical Review B\n |volume=38 |issue=7 |pages=5142\u20135145\n |bibcode=1988PhRvB..38.5142K |doi=10.1103/PhysRevB.38.5142 |pmid=9946940\n}}\n</ref> The confirmation of the ''d''-wave nature of the cuprate superconductors was made by a variety of experiments, including the direct observation of the ''d''-wave nodes in the excitation spectrum through Angle Resolved Photoemission Spectroscopy, the observation of a half-integer flux in tunneling experiments, and indirectly from the temperature dependence of the penetration depth, specific heat and thermal conductivity.\n\nThe superconductor with the highest transition temperature at ambient pressure is the cuprate of mercury, barium, and calcium, at around 133 K.<ref name=Schi>\n{{cite journal\n |last1=Schilling |first1=A.    |last2=Cantoni |first2=M.\n |last3=Guo       |first3=J.D.  |last4=Ott     |first4=H.R.\n |year=1993\n |title=Superconductivity in the Hg-Ba-Ca-Cu-O system\n |journal=Nature\n |volume=363 |issue=6424 |pages=56\u201358\n |doi=10.1038/363056a0  |bibcode=1993Natur.363...56S  |s2cid=4328716\n}}\n</ref> There are other superconductors with higher recorded transition temperatures - for example lanthanum superhydride at 250 K, but these only occur at very high pressures.<ref name=eremets>\n{{cite journal\n  |last1=Drozdov    |first1=A.P.  |last2=Kong        |first2=P.P.\n  |last3=Minkov     |first3=V.S.  |last4=Besedin     |first4=S.P.\n  |last5=Kuzovnikov |first5=M.A.  |last6=Mozaffari   |first6=S.\n  |last7=Balicas    |first7=L.    |last8=Balakirev   |first8=F.F.\n  |last9=Graf       |first9=D.E.  |last10=Prakapenka |first10=V.B.\n  |last11=Greenberg |first11=E.   |last12=Knyazev    |first12=D.A.\n  |last13=Tkacz     |first13=M.   |last14=Eremets    |first14=M.I.\n  |year=2019\n  |title=Superconductivity at 250 K in lanthanum hydride under high pressures\n  |journal=Nature\n  |volume=569  |issue=7757  |pages=528\u2013531\n  |doi=10.1038/s41586-019-1201-8  |arxiv=1812.01561  |pmid=31118520\n  |bibcode=2019Natur.569..528D   |s2cid=119231000\n}}\n</ref>\n\nThe origin of high-temperature superconductivity is still not clear, but it seems that instead of ''electron-[[phonon]]'' attraction mechanisms, as in conventional superconductivity, one is dealing with genuine ''electronic'' mechanisms (e.g. by antiferromagnetic correlations), and instead of conventional, purely [[atomic orbital|''s''-wave]] pairing, more exotic pairing symmetries are thought to be involved (''d''-wave in the case of the cuprates; primarily extended ''s''-wave, but occasionally ''d''-wave, in the case of the iron-based superconductors). \nIn 2014, evidence showing that fractional particles can happen in quasi two-dimensional magnetic materials, was found by EPFL scientists<ref>\n{{cite journal\n |last1=Dalla Piazza |first1=B. |last2=Mourigal |first2=M.\n |last3=Christensen |first3=N. B. |last4=Nilsen |first4=G. J.\n |last5=Tregenna-Piggott |first5=P. |last6=Perring |first6=T. G.\n |last7=Enderle |first7=M. |last8=McMorrow |first8=D. F.\n |last9=Ivanov |first9=D. A. |last10=R\u00f8nnow |first10=H. M.\n |display-authors=6\n |year=2015\n |title=Fractional excitations in the square-lattice quantum antiferromagnet\n |journal=Nature Physics\n |volume=11  |issue=1  |pages=62\u201368\n |doi=10.1038/nphys3172  |pmid=25729400  |pmc=4340518  |arxiv=1501.01767\n |bibcode=2015NatPh..11...62D\n}}\n</ref> lending support for Anderson's theory of high-temperature superconductivity.<ref>\n{{cite press release\n |title=How electrons split: New evidence of exotic behaviors\n |date=Dec 23, 2014\n |website=Nanowerk\n |publisher=\u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne\n |url=http://www.nanowerk.com/nanotechnology-news/newsid=38557.php\n |access-date=Dec 23, 2014  |url-status=live\n |archive-url=https://web.archive.org/web/20141223224211/http://www.nanowerk.com/nanotechnology-news/newsid=38557.php\n |archive-date=December 23, 2014\n}}\n</ref>"}},
{"article_title": "8-track tape", "pageid": "101596", "revid": "1060010515", "timestamp": "2021-12-12T23:47:00Z", "history_paths": [["8-track tape --- Introduction ---", "History"]], "categories": ["audiovisual introductions in 1964", "audio storage", "tape recording", "discontinued media formats", "quadraphonic sound", "american inventions", "1964 in music", "1964 in technology", "products introduced in 1964", "1970s fads and trends"], "heading_tree": {"8-track tape --- Introduction ---": {"History": {"Development of tape cartridges": {}, "Introduction of Stereo 8": {}, "Commercial success": {}, "Early karaoke machines": {}, "Nature and operation": {}, "Quad 8 and Q8": {}, "Other use": {}, "Decline": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"8-track tape --- Introduction ---|History": "The original format for [[magnetic tape]] sound reproduction was the [[reel-to-reel audio tape recording|reel-to-reel tape recorder]], first available in the United States in the late 1940s, but too expensive and bulky to be practical for amateur home use until well into the 1950s. Loading a reel of tape onto the machine and threading it through the various guides and rollers proved daunting to some casual users \u2014 certainly, it was more difficult than putting an LP record on a record player and flicking a switch. Because, in the early years, each tape had to be dubbed from the master tape in real-time to maintain good sound quality, pre-recorded tapes were more expensive to manufacture, and costlier to buy, than [[phonograph record|vinyl records]], which could be stamped far more quickly than their own playing time.\n\nTo eliminate the inconvenience of tape-threading, various manufacturers introduced cartridges that held the tape inside a metal or plastic housing, thereby eliminating handling. Most were intended only for low-fidelity voice recording in dictation machines. The first tape cartridge designed for general consumer use, including music reproduction, was the Sound Tape or Magazine Loading Tape Cartridge ([[RCA tape cartridge]]), introduced in 1958. Pre-recorded [[stereophonic sound|stereophonic]] music cartridges were available, and blank cartridges could be used to make recordings at home, but the format failed to gain popularity.\n\n [[File:Quad 8 Track (white background).jpg|thumb|A blank 8-track cartridge.]]\n[[File:Unitape-8-track-recordimg-cartridge.jpg|thumb|Blank cartridges could be used to make recordings at home.]]\n\nThe [[Endless tape cartridge|endless loop tape cartridge]] was first designed in 1952 by Bernard Cousino around a single reel carrying a continuous loop of standard 1/4-inch, plastic, oxide-coated recording tape, running at {{convert|3.75|in|cm|2|abbr=on}} per second. Program starts and stops were signaled by a one-inch-long metal foil that activated the track-change sensor.\n\nInventor George Eash invented a design in 1953, called the [[Fidelipac]] cartridge.<ref>{{cite magazine|url= https://books.google.com/books?id=BikEAAAAMBAJ&q=George+Eash+CARtridge+inventor+tells+how+it+was+born&pg=RA1-PA19 |title=George Eash CARtridge inventor tells how it was born |magazine=Billboard |date=3 March 1966 |volume=78 |issue=10 |access-date=26 January 2013 }}</ref> The Eash cartridge was later licensed by manufacturers, notably the Collins Radio Company, which first introduced a cartridge system for broadcasting at the National Association of Broadcasters 1959 annual show. Fidelipac cartridges (nicknamed "carts" by DJs and radio engineers) were used by many radio stations for commercials, jingles, and other short items. Eash later formed the Fidelipac Corporation to manufacture and market tapes and recorders, as did several others, including Audio-Pak (Audio Devices Corp.).\n\nThere were several attempts to sell music systems for cars, beginning with the Chrysler [[Highway Hi-Fi]] of the late 1950s, which used [[phonograph record|discs]]. However, entrepreneur, marketer and television set dealer, [[Madman Muntz|Earl "Madman" Muntz]], of [[Los Angeles, California]], saw a potential in the "broadcast carts" for an automobile music system. In 1962, he introduced his [[Stereo-Pak]] four-track cartridge stereo system and tapes, mostly in [[California]] and [[Florida]]. The four tracks were divided into two "programs", typically corresponding to the two sides of an [[LP record]], with each program comprising two tracks read simultaneously for stereo (two channel) sound playback. He licensed popular music albums from the major record companies and duplicated them on the four-track cartridges, or "CARtridges", as they were first advertised.\n\n [[File:Lear Jet Stereo 8 advertisement.png|thumb|Lear Jet Stereo 8 advertisement, ''[[Billboard (magazine)|Billboard]]'' July 16, 1966]]\nThe Lear Jet Stereo 8 cartridge was designed by Richard Kraus while working for the [[Lear Jet Corporation]], under [[Bill Lear]], in 1963. The major change was to incorporate a neoprene rubber and nylon pinch roller into the cartridge itself, rather than to make the pinch roller a part of the tape player, reducing mechanical complexity. Lear also eliminated some of the internal parts of the Eash cartridge, such as the tape-tensioning mechanism and an interlock that prevented tape slippage. By doubling the number of tracks from 4 to 8,<ref>https://www.ischool.utexas.edu/~cochinea/html-paper/a-crews-03-magnetic-media.html {{dead link|date=September 2021}}</ref> the length of any recording doubled to 80 minutes.\n\nIn 1964, Lear's aircraft company constructed 100 demonstration Stereo 8 players for distribution to executives at RCA and the auto companies.\n\n [[File:1967 Marlin gold ny-inf.jpg|thumb|right|Factory optional 8-track stereo player in a 1967 [[American Motors]] [[Rambler Marlin|Marlin]] mounted between the [[Center console (automobile)|center console]] and dash]]\n[[File:1978 AMC Matador sedan red NC detail of factory AM-FM-stereo-8-track unit.jpg|thumb|Factory installed AM/FM radio/8-track unit in a 1978 [[AMC Matador]] with a ''[[Briefcase Full of Blues]]'' cartridge in "play" position]]\n\nThe popularity of both four-track and eight-track cartridges grew from the booming automobile industry.<ref>{{cite web |url=http://www.videointerchange.com/audio_history.htm |title=Vintage Audio Recording History |publisher=Videointerchange.com |date=10 May 2012 |access-date=27 January 2013 }}</ref> In September 1965, the [[Ford Motor Company]] introduced factory-installed and dealer-installed eight-track tape players as an option on three of its 1966 models (the sporty [[Ford Mustang|Mustang]], luxurious [[Ford Thunderbird|Thunderbird]], and high-end [[Lincoln (automobile)|Lincoln]]),<ref>{{Cite news |url=https://www.nytimes.com/1976/01/25/archives/some-help-from-debussy-for-the-hassled-driver.html|title=Some Help From Debussy For the Hassled Driver |last=Despagni |first=Anthony J.|date=1976 |newspaper=[[The New York Times]] |access-date=2017-09-29 |language=en-US |issn=0362-4331}}</ref> and RCA Victor introduced 175 Stereo-8 Cartridges from its RCA Victor and RCA Camden labels of recording artists catalogs.<ref name="Billboard Sep 1965">{{cite magazine |title=RCA Fires 175-Title Burst with Release of Stereo 8 Cartridges | magazine=Billboard |volume=77 |issue=39 |page=3 |date=25 September 1965 |url=https://books.google.com/books?id=HCkEAAAAMBAJ&pg=PA3 |issn=0006-2510 |access-date=27 January 2013 }}</ref> By the 1967 model year, all of Ford's vehicles offered this tape player upgrade option. Most of the initial factory installations were separate players from the radio (such as shown in the image), but [[dashboard]] mounted 8-track units were offered in combination with an AM radio, as well as with AM/FM receivers.<ref>{{cite book |url=https://books.google.com/books?id=JHVaQFDrx_MC&q=AMC+AM/8-track+stereo+tape+player&pg=RA1-PT16 |page=73 |last=Mitchell |first=Larry G. |title=AMC Muscle Cars | year=2000 |publisher=MBI Publishing |isbn=978-0-7603-0761-8 |access-date=26 January 2013 }}</ref> Muntz, and a few other manufacturers, also offered 4/8 or "12-track" players that were capable of playing cartridges of either format, 4-track or 8-track. With the backing of the U.S. automakers, the eight-track format quickly won out over the four-track format, with Muntz abandoning it completely by late 1970.\n\nThe 8-track format gained steadily in popularity because of its convenience and portability. Home players were introduced in 1966 that allowed consumers to share tapes between their homes and portable systems. By the late 1960s, the 8-track segment was the largest in the consumer electronics market and the popularity of 8-track systems for cars helped generate demand for home units.<ref>{{cite magazine |url=https://books.google.com/books?id=sgoEAAAAMBAJ&q=8-track+segment+of+this+booming+market+is+by+far+the+largest&pg=RA1-PA32 |title=8-track market booms |first=Oscar P. |last=Kussisto |magazine=Billboard |date=2 November 1968 |access-date=23 April 2014}}</ref> "Boombox" type portable players were also popular but eight-track player/recorders failed to gain wide popularity and few manufacturers offered them except for manufacturer Tandy Corporation (for its [[Radio Shack]] electronics stores). With the availability of cartridge systems for the home, consumers started thinking of eight-tracks as a viable alternative to 33 rpm album style [[vinyl record]]s, not only as a convenience for the car. Also by the late 1960s, prerecorded releases on the 8-track tape format began to arrive within a month of the vinyl release. The 8-track format became by far the most popular and offered the largest music library of all the tape systems.<ref>{{cite journal|url= https://books.google.com/books?id=5ikDAAAAMBAJ&q=Eight-track+by+far+the+most+popular+offers+the+largest+music+library&pg=PA128 |title=The best tape system for you |first=Sam |last=Shatavsky |journal=Popular Science |date=February 1969 |pages=126\u2013129 |volume=194 |issue=2}}</ref> \nEight-track players were fitted as standard equipment in most [[Rolls-Royce]] and [[Bentley]] cars of the period for sale in [[Great Britain]] and worldwide. Optional 8-track players were available in many cars and trucks through the early 1980s.\n\nAmpex, based in [[Elk Grove Village, Illinois]], set up a European operation (Ampex Stereo Tapes) in London, England, in 1970 to promote 8-track product and [[Cassette tape|musicassettes]] in [[United Kingdom|Britain]] and Europe, but it struggled and folded in 1974.{{Verify source|date=January 2014}} GRT Corporation, [[General Recorded Tape]] of Sunnyvale, California, was another large manufacturer which duplicated many tapes for smaller record labels; it went out of business in 1979.\n\n[[Quadraphonic]] sound on eight-track cartridges was announced by RCA in April 1970. It employed four-channel receiver/amplifiers that balanced the sound via sliders or a joystick.\n\nFord was particularly eager to promote in-car quadraphonic players as a pricey option, being the only "Big Four" American automotive company to do so.{{citation needed|date=August 2019}} The format enjoyed moderate success in the early 1970s but faded by mid-decade. Quadraphonic cartridges provided four channels of discrete sound, unlike [[Matrix decoder|matrixed]] formats such as SQ, which [[Columbia Records|Columbia]]/[[Sony Music Entertainment|CBS Records]] used for their quadraphonic sound vinyl records.{{citation needed|date=August 2019}}\n\n [[Daisuke Inoue]] invented the first karaoke machine in 1971 called the Juke-8.<ref>{{cite book |last1=Raftery |first1=Brian |title=Don't Stop Believin': How Karaoke Conquered the World and Changed My Life |date=2008 |publisher=Da Capo Press |location=Boston, Massachusetts |isbn=978-0306815836 |url-access=registration |url=https://archive.org/details/dontstopbelievin00raft}}</ref><ref>{{cite book |last1=Mitsui |first1=T\u014dru |last2=Hosokawa |first2=Sh\u016bhei |title=Karaoke around the world: global technology, local singing |date=1998 |publisher=Routledge |location=London ; New York |isbn=9781280140877 |pages=29\u201342}}</ref>\n\n An 8-track cartridge provides four pairs of stereo tracks, whereas the later quadraphonic cartridges had two sets of four tracks. The ends of the tape were spliced with a thin strip of metal that would trigger a solenoid that would cause the playback heads to automatically jump to the next set of channels. Both types of players also provided a button for manually changing channels. Due to the design of the endless loop tape, which fed from the reel in only one direction, there was no rewind control. Due to the mechanical stress on the tape, few machines offered a fast-forward control.\n\n The [[audio mixing]] process for four channel [[quadraphonic sound]] is different than for stereo versions of the same recording. Some producers opted for strong separation between channels and this was regularly used for popular music. Others chose a style in which there is only surround sound ambience or "echo" heard in the rear speakers. This type of sound, which can realistically reproduce a live concert hall experience, was commonly used for classical music. However, mixing engineers could also aim for more of a hybrid effect. In some situations sounds move in rotation around a three dimensional space. While rarely heard, the four channel effect can be quite spectacular. Quadraphonic recordings are often highly regarded and some quad 8-tracks have become highly collectible. Beginning in the 1990s many four channel recordings were reissued on modern digital formats such as [[Super Audio CD]].\n\n [[Milton Bradley]]'s (MB) [[OMNI Entertainment System]] was an electronic quiz machine game first released in 1980, similar to ''[[Jeopardy! (video game)|Jeopardy!]]'' or later [[You Don't Know Jack (franchise)|''You Don't Know Jack'' video game series]], using 8-track tapes for playback analog audio for questions, instructions and answers as well as digital signals in [[magnetic tape data storage]] on remaining tracks to load the right answer for counting the score. In 1978, the [[Mego Corporation]] launched the [[2-XL]] toy robot, which utilized the tracks for determining right from wrong answers.<ref>[[Techmoan]]: [https://www.youtube.com/watch?v=zyOKgLtUxto MB OMNI Entertainment System - The 1980s 8-Track games machine], YouTube, 6 August 2017</ref> In 1977, the Scottish company GR International released the Bandmaster Powerhouse, a drum machine that played back custom-made 8-track cartridges containing drum and percussion rhythms loops recorded with real instruments. These could be subjected to a degree of processing using the drum machine's controls, which included tempo and instrument balance.<ref>{{Cite web|url=http://www.vintagesynth.com/grinternational/bandmaster-powerhouse/|title=GR International Bandmaster Powerhouse | Vintage Synth Explorer}}</ref>\n\n 1978 was the peak year for 8-track sales in the United States, with sales declining quite rapidly from then on.<ref>{{Cite web|url=https://www.riaa.com/u-s-sales-database/|title = U.S. Sales Database}}</ref> Eight-track players became less common in homes and vehicles in the late 1970s. The [[compact cassette]] had arrived in 1963<ref>{{Cite web |url=https://southtree.com/blogs/artifact/the-convenience-of-the-cassette |title=The History of the Audio Cassette |website=Southtree |access-date=2019-12-15}}</ref> and, by the late 1970s, the eight-track cartridges had greatly diminished in popularity. In some [[Latin America]]n and European countries, the format was abandoned in the mid-1970s in favor of the smaller [[cassette tape]], which was one-third the size.\n\nIn the U.S., eight-track cartridges were phased out of retail stores in late 1982 and early 1983. However, some titles were still available as eight-track tapes through [[Columbia House]] and [[RCA]] (BMG) Music Service ''Record Clubs'' until late 1988. Until 1990, [[Radio Shack]] (Tandy Corporation) continued to sell blank eight-track cartridges and players for home recording use under its [[Realistic (brand)|Realistic]] brand.<ref>{{Cite web |url=http://www.radioshackcatalogs.com/catalogs/1990/ |title=1990 Radio Shack Catalog|website=www.radioshackcatalogs.com}}</ref>\n\nThe professional broadcast cart format survived for more than another decade, being used for jingles, advertisements, station identifications, and limited music content at most local radio stations, before being replaced by computer-generated sound in the 1990s. The format also continued in use for relatively short sound loops, in which a rapid start was more important than other criteria. The endless-loop tape concept continued to be used in newer cinema [[movie projector]]s, though their tape spool is actively rotated and not drawn by tension on the film. That technology is now almost entirely supplanted by [[digital cinema]]."}},
{"article_title": "Obelisk", "pageid": "101600", "revid": "1055054037", "timestamp": "2021-11-13T15:51:07Z", "history_paths": [["Obelisk --- Introduction ---", "Ancient obelisks"], ["Obelisk --- Introduction ---", "Modern obelisks"]], "categories": ["obelisks", "ancient egyptian architecture", "monoliths", "types of monuments and memorials", "outdoor sculptures", "sculpture", "stone monuments and memorials", "garden features", "ancient egyptian technology", "egyptian inventions"], "heading_tree": {"Obelisk --- Introduction ---": {"Ancient obelisks": {"Egyptian": {"Nubian": {}, "Ancient Egyptian obelisks in Ancient Rome": {}, "Ancient Egyptian obelisks in modern cities": {}}, "Assyrian": {}, "Axumite (Ethiopia)": {}, "Ancient Roman": {}, "Byzantine": {}, "Pre-Columbian": {}}, "Modern obelisks": {"Post-Egyptian obelisks": {"As commemorative monuments": {}, "Others usages": {}}, "Recent erections of Egyptian obelisks": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Obelisk --- Introduction ---|Ancient obelisks": "Obelisks were prominent in the architecture of the [[ancient Egypt]]ians, and played a vital role in their religion placing them in pairs at the entrance of the [[Egyptian temple|temples]]. The word "obelisk" as used in English today is of Greek rather than Egyptian origin because [[Herodotus]], the Greek traveller, was one of the first classical writers to describe the objects. A number of<!-- can't find a current source, 19th century sources say more --> ancient Egyptian obelisks are known to have survived, plus the "[[Unfinished Obelisk]]" found partly hewn from its quarry at [[Aswan]]. These obelisks are now dispersed around the world, and fewer than half of them remain in Egypt.\n\n[[File:Luxor-Tempel Pylon 08.jpg|thumb|left|[[Pylon (architecture)|Pylon]] of the [[Temple of Luxor]] with the remaining [[Luxor Obelisk]] in front (the second is today on the [[Place de la Concorde]] in Paris).]]\n[[File:Heliopolis200501.JPG|thumb|upright|right|Obelisk of Pharaoh [[Senusret I]], Al-Maalla area of [[Al-Matariyyah]] district in [[Heliopolis (Cairo suburb)|modern Heliopolis]]]]\n\nThe earliest [[temple]] obelisk still in its original position is the {{convert|20.7|m|ft|adj=on|order=flip}} {{convert|120|MT|ST|adj=on|lk=on}}<ref>{{cite web |series=NOVA Online: Mysteries of the Nile |title=A World of Obelisks: Cairo |publisher=[[PBS]] |url=https://www.pbs.org/wgbh/nova/egypt/raising/cairo.html |access-date=14 June 2013}}</ref> red granite Obelisk of [[Senusret I]] of the [[Twelfth Dynasty of Egypt|Twelfth Dynasty]] at [[Al-Matariyyah]] in [[Heliopolis (Cairo suburb)|modern Heliopolis]].<ref>{{cite EB1911 |wstitle=Obelisk |volume=19 |page=945 |first=Francis Llewellyn |last=Griffith}}</ref>\n\nIn [[Egyptian mythology]], the obelisk symbolized the sun god [[Ra]], and during the religious reformation of [[Akhenaten]] it was said to have been a petrified ray of the [[Aten]], the sundisk. [[Benben]] was the mound that arose from the primordial waters [[Naunet|Nu]] upon which the creator god [[Atum]] settled in the creation story of the [[Ancient Egyptian creation myths|Heliopolitan creation myth]] form of Ancient Egyptian religion. The Benben stone (also known as a [[pyramidion]]) is the top stone of the Egyptian pyramid. It is also related to the obelisk.\n\nIt is hypothesized by [[New York University]] [[Egyptologist]] Patricia Blackwell Gary and ''[[Astronomy (magazine)|Astronomy]]'' senior editor Richard Talcott that the shapes of the [[ancient Egypt]]ian [[pyramid]] and obelisk were derived from natural phenomena associated with the sun (the sun-god [[Ra]] being the Egyptians' greatest deity at that time).<ref>{{cite magazine |first1=Patricia |last1=Blackwell Gary |first2=Richard |last2=Talcott |date=June 2006 |title=Stargazing in Ancient Egypt |magazine=[[Astronomy (magazine)|Astronomy]] |pages=62\u201367 |url=http://www.astronomy.com/~/media/import/files/pdf/8/6/c/august_2010_we_stargazing-in-ancient-egypt.pdf |access-date=2021-01-30 |url-status=live}}</ref> The [[pyramid]] and obelisk's significance have been previously overlooked, especially the astronomical phenomena connected with [[sunrise]] and [[sunset]]: [[Zodiacal light]] and [[sun pillar]]s respectively.\n\n Ancient [[Nubia|Nubian kings]] of the [[Twenty-fifth Dynasty of Egypt|twenty-fifth Dynasty]] sought to legitimize their rule over Egypt by constructing Egyptianizing monuments in the Middle Nile region. Historical sources mention that king [[Piye]] built at least one obelisk. The obelisk was made of local [[black granite]] and was found  at the site of [[Kadakol]]. It had been cut down to make it into a column, presumably for one of the early Christian churches in the area of [[Old Dongola]]. Today the obelisk is exhibited in the [[National Museum in Khartoum]].<ref>{{cite journal |last=Lacovara |first=Petere |title=Pyramids and Obelisks beyond Egypt |journal=Aegyptiaca |date=2018 |issue=2 |page=130 |doi=10.11588/aegyp.2018.2.48018 |url=https://journals.ub.uni-heidelberg.de/index.php/aegyp/article/view/48018/41478 |access-date=17 June 2019}}</ref> The obelisk is inscribed with the kings official titulary: ''Strong-bull, Appearing-in-Dominion (Thebes), King-of-Upper-and-Lower-Egypt, Two-ladies, Ruler-of-Egypt, Son-of-R\u00ea, Pi(ankh)y: what he made as his monument for his father Amen-R\u00ea, lord of [...]''.<ref>{{cite journal |last1=Tormod |first1=Eide |title=Fontes historiae Nubiorum: Textual Sources for the History of the Middle Nile region between the eighth century BC and the sixth century AD |volume=1 |issue=54 |page=54}} {{full citation|date=January 2021|reason=missing journal name}}</ref>\n\nAn obelisk of King [[Senkamanisken]] was found at [[Gebel Barkal]] in 1916 by the [[Harvard University]] Museum of Fine Arts expedition to [[Sudan]]. There are remains of another small obelisk inscribed with the [[cartouche]] of King [[Aktisanes]] at the site of Gebel Barkal.<ref>{{cite journal |last=Lacovara |first=Petere |year=2018 |title=Pyramids and obelisks beyond Egypt |journal=Aegyptiaca |issue=2 |pages=131\u2013135 |doi=10.11588/aegyp.2018.2.48018 |url=https://journals.ub.uni-heidelberg.de/index.php/aegyp/article/view/48018/41478 |access-date=17 June 2019}}</ref>\n\n {{See also|List_of_obelisks_in_Rome#Ancient_Egyptian_obelisks|label 1=List of Ancient Egyptian obelisks in Rome}}\nAround 30 BCE, after [[Cleopatra]], "the last Pharaoh", committed suicide, Rome seized control of Egypt. The Ancient Romans looted the various [[Egyptian temple|temple]] complexes, in one case they destroyed walls at the [[Karnak|Temple of Karnak]] to haul them out. There are now more than twice as many obelisks that were seized and shipped out by Rome as remain in Egypt. The majority were dismantled during the Roman period over 1,700 years ago and the obelisks were sent to different locations.\n\nThe largest standing and tallest Egyptian obelisk is the [[Lateran Obelisk]] in the square at the west side of the [[Lateran Basilica]] in Rome at {{convert|105.6|ft|m}} tall and a weight of {{convert|455|MT|ST}}.<ref  name=PBS-Nile-mysteries-Rome>{{cite web |series=NOVA Online: Mysteries of the Nile |title=A World of Obelisks: Rome |publisher=[[PBS]] |url=https://www.pbs.org/wgbh/nova/egypt/raising/rome.html |access-date=14 June 2013}}</ref> More well known is the [[Cultural icon|iconic]] {{convert|25|m|ft}}, {{convert|331|MT|ST|adj=on}} obelisk at [[Saint Peter's Square]].<ref name=PBS-Nile-mysteries-Rome/> Brought to Rome by the Emperor [[Caligula]] in 37 CE, it has stood at its current site and on the wall of the [[Circus of Nero]], flanking St Peter's Basilica.\n\n{{quote|The elder [[Pliny the Elder|Pliny]] in his ''[[Pliny's Natural History|Natural History]]'' refers to the obelisk's transportation from Egypt to Rome by order of the Emperor Gaius (Caligula) as an outstanding event. The barge that carried it had a huge mast of fir wood which four men's arms could not encircle. One hundred and twenty bushels of lentils were needed for ballast. Having fulfilled its purpose, the gigantic vessel was no longer wanted. Therefore, filled with stones and cement, it was sunk to form the foundations of the foremost quay of the new harbour at [[Ostia Antica|Ostia]].<ref>{{cite book |first=James |last=Lees-Milne |author-link=James Lees-Milne |title=Saint Peter's |year=1967}}</ref>}}\n\nPope [[Sixtus V]] was determined to erect the obelisk in front of St Peter's, of which the nave was yet to be built. He had a full-sized wooden mock-up erected within months of his election. [[Domenico Fontana]], the assistant of [[Giacomo Della Porta]] in the Basilica's construction, presented the Pope with a little model crane of wood and a heavy little obelisk of lead, which Sixtus himself was able to raise by turning a little winch with his finger. Fontana was given the project. Half-buried in the debris of the ages, it was first excavated as it stood; then it took from 30 April to 17 May 1586 to move it on rollers to the Piazza: it required nearly 1000 men, 140 carthorses, and 47 cranes. The re-erection, scheduled for 14 September, the Feast of the [[Exaltation of the Cross]], was watched by a large crowd. It was a famous feat of engineering, which made the reputation of Fontana, who detailed it in a book illustrated with copperplate etchings, ''Della Trasportatione dell'Obelisco Vaticano et delle Fabriche di Nostro Signore Papa Sisto V'' (1590),<ref>{{cite web |title=Della trasportatione dell\u00aaobelisco Vaticano et delle fabriche di Nostro Signore Papa Sisto ... |website=purl.pt |url=http://purl.pt/6256/1/index.html}}</ref><ref>{{cite web |title=Della trasportatione dell'obelisco vaticano et delle fabriche di nostro signore papa Sisto V fatte dal cavallier Domenico Fontana, architetto di Sva Santita, libro primo |website=NYPL Digital Collections |url=http://digitalgallery.nypl.org/nypldigital/dgkeysearchresult.cfm?parent_id=350916&word= |access-date=21 August 2015}}</ref> which itself set a new standard in communicating technical information and influenced subsequent architectural publications by its meticulous precision.<ref>{{cite web |last=Fontana |first=Domenico |year = 1590 |title=Moving the Obelisk |website=Martayan Lan Rare Books |publisher=Domenico Basa |place=Rome, IT |url=http://www.martayanlan.com/cgi-bin/display.cgi/Books/5/28/25/606 |access-date=21 August 2015 |archive-url=https://web.archive.org/web/20120315090244/http://www.martayanlan.com/cgi-bin/display.cgi/Books/5/28/25/606 |archive-date=21 May 2013 |url-status=dead |df=dmy-all}}</ref> Before being re-erected the obelisk was exorcised. It is said that Fontana had teams of relay horses to make his getaway if the enterprise failed. When [[Carlo Maderno]] came to build the Basilica's nave, he had to put the slightest kink in its axis, to line it precisely with the obelisk.\n\nThree more obelisks were erected in Rome under Sixtus V: at [[Santa Maria Maggiore]], in 1587; at the Lateran Basilica, in 1588; and at the [[Piazza del Popolo]], in 1589.<ref>{{cite book |last=Fontana |first=Domenico |year=1590 |title=Della trasportatione dell'obel |publisher=ETH-Bibliothek \u2013 e-rara |place=Z\u00fcrich (NEBIS) |doi=10.3931/e-rara-117}}</ref> An obelisk stands in front of the church of [[Trinit\u00e0 dei Monti]], at the head of the [[Spanish Steps]]. Another obelisk in Rome is sculpted as carried on the back of an [[elephant]]. Rome lost one of its obelisks, the [[Boboli obelisk]] which had decorated the temple of Isis, where it was uncovered in the 16th century. The Medici claimed it for the [[Villa Medici]], but in 1790 they moved it to the [[Boboli Gardens]] attached to the [[Palazzo Pitti]] in [[Florence]], and left a replica in its place.\n\nNot all the Egyptian obelisks in the Roman Empire were set up at Rome: [[Herod the Great]] imitated his Roman patrons and set up a red granite Egyptian obelisk in the [[hippodrome]] of his new city [[Caesarea Maritima|Caesarea]] in northern [[Judea]]. This one is about {{convert|40|ft|m}} tall and weighs about {{convert|100|MT|ST}}.<ref>{{cite web |title=Caesarea Obelisk |publisher=Highskyblue.web.fc2.com |date=18 June 2001 |url=http://highskyblue.web.fc2.com/caesarea.htm |access-date=14 June 2013}}</ref> It was discovered by archaeologists and has been re-erected at its former site.\n\nIn 357 CE, Emperor [[Constantius II]] had two Karnak Temple obelisks removed and transported down the [[Nile]] to [[Alexandria]] to commemorate his ''ventennalia'', the 20th year of his reign. Afterward, one was sent to Rome and erected on the ''[[spina (Roman circus)|spina]]'' of the [[Circus Maximus]], and is today known as the Lateran Obelisk. The other one, known as the [[Obelisk of Theodosius]], remained in Alexandria until 390 CE, when Emperor [[Theodosius I]] had it transported to Constantinople (now [[Istanbul]]) and put up on the ''spina'' of the [[Hippodrome of Constantinople]] (now Sultan Ahmet Square).<ref>{{cite book | last=Habachi | first=Labib | author-link=Labib Habachi | year=1985 | title=The Obelisks of Egypt: Skyscrapers of the past | publisher=American University in Cairo Press | isbn=978-9774240225 | pages=145\u2013151 }}</ref> It once stood {{convert|95|ft|m}} tall and weighed {{convert|380|MT|ST}}; however, its lower section (which reputedly also once stood in the hippodrome) is now lost, reducing the obelisk's size to {{convert|65|ft|m}}.<ref name=PBS-Nile-mysteries-Istanbul>{{cite web |series=NOVA Online: Mysteries of the Nile |title=A World of Obelisks: Istanbul |publisher=[[PBS]] |url=https://www.pbs.org/wgbh/nova/egypt/raising/istanbul.html |access-date=14 June 2013}}</ref>\n\n [[Image:Obelisk5.jpg|right|thumb|Tip of Hatshepsut's fallen obelisk, [[Karnak|Karnak Temple Complex]], [[Luxor]], [[Egypt]] ]]\nThe Ancient Romans populated their city with 8 large and 42 small Egyptian obelisks. More have been re-erected elsewhere, and the best-known examples outside Rome are the pair of {{convert|21|m|ft|adj=on}} {{convert|187|MT|ST|adj=on}} [[Cleopatra's Needle (London)|Cleopatra's Needle]]s in [[London|London, England]] ({{convert|69|ft|m|order=flip|disp=or}}), and [[New York City|New York City, USA]] ({{convert|70|ft|m|order=flip|disp=or}}), and the {{convert|75|ft|m|adj=on|order=flip}} over-{{convert|250|MT|ST|adj=on|abbr=}} [[Luxor Obelisk]] at the [[Place de la Concorde]] in [[Paris, France]].<ref>{{cite web |series=NOVA Online | Mysteries of the Nile |title=A World of Obelisks: World |publisher=[[PBS]] |url=https://www.pbs.org/wgbh/nova/egypt/raising/world.html |access-date=14 June 2013}}</ref>\n\nObelisks were being shipped out of [[Egypt]] as late as the nineteenth century when three of them were sent to [[London]], [[New York City|New York]] and [[Paris]]. Their transportation was covered by various newspapers.<ref name="Paris obelisk">{{cite journal |last=Brier |first=Bob |year=2018 |title=The secret life of the Paris obelisk |journal=Aegyptiaca |issue=2 |pages=75\u201391 |doi=10.11588/aegyp.2018.2.47945 |url=https://journals.ub.uni-heidelberg.de/index.php/aegyp/article/view/47945/41416 |access-date=18 June 2019}}</ref>\n\n[[Image:Hippodrome Oblisk.jpg|upright|thumb|The [[Obelisk of Theodosius|Obelisk of Tuthmosis III]], [[Istanbul]], [[Turkey]]]]\n[[Image:Bartholomeus Breenbergh 002.jpg|upright|thumb|The [[Dutch Golden Age]] painter [[Bartholomeus Breenbergh]] placed an obelisk in the background of his 1655 painting ''Joseph Sells Grain'']]\nThere are ancient Egyptian obelisks in the following locations:\n* Egypt \u2013 11\n**Pharaoh [[Seti II]], Karnak Temple, Luxor, {{convert|7|m|ft|abbr=on}}\n**Pharaoh [[Thutmosis I]], [[Karnak|Karnak Temple]], [[Luxor]]\n**Pharaoh [[Ramses II]], [[Luxor Temple]]\n**Pharaoh [[Hatshepsut]], Karnak Temple, Luxor\n**Pharaoh [[Senusret I]], Al-Masalla area of [[Al-Matariyyah]] district in [[Heliopolis (Cairo suburb)|Heliopolis]], [[Cairo]]\n**Pharaoh [[Ramses II]], [[Tahrir Square]], [[Cairo]]\n**Pharaoh [[Ramses III]], [[Luxor Museum]]\n**Pharaoh [[Ramses II]], [[Gezira Island]], Cairo, {{convert|20.4|m|ft|abbr=on}}<ref>{{cite web |title=History of the Egyptian Obelisks |url=http://egipto.com/obeliscos/cairo2.html |access-date=21 August 2015}}</ref>\n**Pharaoh [[Ramses II]], [[Cairo International Airport]], {{convert|16.97|m|ft|abbr=on}}\n**Pharaoh [[Hatshepsut]], "[[Unfinished obelisk|The Unfinished obelisk]]", Stone Quarries, [[Aswan]]\n**Pharaoh [[Senusret I]], [[Faiyum]]\n*France \u2013 1\n**Pharaoh [[Ramses II]], [[Luxor Obelisk]], in [[Place de la Concorde]], Paris<ref name="Paris obelisk"/>\n*Israel \u2013 1\n**[[Caesarea obelisk]]\n*Italy \u2013 13 (includes the only one located in the [[Vatican City]])\n**Rome \u2014 8 ancient Egyptian obelisks ''(see [[List of obelisks in Rome]])''\n**Piazza del Duomo, [[Catania]] ([[Sicily]])\n**[[Boboli Obelisk]] ([[Florence]])\n**[[Urbino]]\n*Poland \u2013 1\n**Pharaoh [[Ramses II]], Pozna\u0144 Archaeological Museum, [[Pozna\u0144]] (on loan from \u00c4gyptisches Museum und Papyrussammlung, Berlin)<ref>{{cite web |title=Obelisk of Ramesses II in the Museum's courtyard |website=Muzeum Archeologiczne w Poznaniu |url=http://www.muzarp.poznan.pl/en/exhibitions/permanent/obelisk-of-ramesses-ii-in-the-museums-courtyard/ |access-date=21 August 2015}}</ref>\n*Turkey \u2013 1\n**Pharaoh [[Tuthmosis III]], the [[Obelisk of Theodosius]] in the [[Hippodrome of Constantinople]] (now Sultan Ahmet Square), [[Istanbul]]\n*United Kingdom \u2013 4\n**Pharaoh [[Tuthmosis III]], "[[Cleopatra's Needle (London)|Cleopatra's Needle]]", beside the Thames [[Victoria Embankment]], in London\n**Pharaoh [[Amenhotep II]], in the Oriental Museum, [[University of Durham]]\n**Pharaoh [[Ptolemy IX]], [[Philae obelisk]], at [[Kingston Lacy]], near [[Wimborne Minster]], [[Dorset]]\n**Pharaoh [[Nectanebo II]], [[British Museum]], London (pair of obelisks)\n*United States \u2013 1\n**Pharaoh [[Tuthmosis III]], "[[Cleopatra's Needle (New York)|Cleopatra's Needle]]", in [[Central Park]], [[New York (state)|New York]]\n\n Obelisk monuments are also known from the [[Assyria]]n civilization, where they were erected as public monuments that commemorated the achievements of the Assyrian king.\n\nThe [[British Museum]] possesses four Assyrian obelisks:\n\nThe [[White Obelisk of Ashurnasirpal I]] (named due to its colour), was discovered by [[Hormuzd Rassam]] in 1853 at [[Nineveh]]. The obelisk was erected by either [[Ashurnasirpal I]] (1050\u20131031 BCE) or [[Ashurnasirpal II]] (883\u2013859 BCE). The obelisk bears an inscription that refers to the king's seizure of goods, people and herds, which he carried back to the city of Ashur. The reliefs of the Obelisk depict military campaigns, hunting, victory banquets and scenes of tribute bearing.\n\nThe Rassam Obelisk, named after its discoverer [[Hormuzd Rassam]], was found on the citadel of [[Nimrud]] (ancient Kalhu). It was erected by Ashurnasirpal II, though only survives in fragments. The surviving parts of the reliefs depict scenes of tribute bearing to the king from Syria and the west.<ref>{{cite web |title=Rassam Obelisk |series=Collection object details |website=British Museum |url=https://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=366799&partId=1&searchText=Rassam+Obelisk&page=1}}</ref>\n\nThe [[Black Obelisk]] was discovered by [[Sir Austen Henry Layard]] in 1846 on the citadel of Kalhu. The obelisk was erected by [[Shalmaneser III]] and the reliefs depict scenes of tribute bearing as well as the depiction of two subdued rulers, [[Jehu]] the Israelite, and Sua the Gilzanean, making gestures of submission to the king. The reliefs on the obelisk have accompanying epigraphs, but besides these the obelisk also possesses a longer inscription that records one of the latest versions of Shalmaneser III's annals, covering the period from his accessional year to his 33rd regnal year.\n\nThe Broken Obelisk, that was also discovered by Rassam at Nineveh. Only the top of this [[monolith]] has been reconstructed in the British Museum. The obelisk is the oldest recorded obelisk from Assyria, dating to the 11th century BCE.<ref>{{cite web |title=Broken Obelisk |series=Collection object details |website=British Museum |url=https://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=277955&partId=1&searchText=Broken+Obelisk&page=1}}</ref>\n\n [[Image:Stela aksum.jpg|thumb|upright|[[King Ezana's Stele]] in [[Axum]]]]\nA number of obelisks were carved in the ancient [[Axumite Kingdom]] of today northern [[Ethiopia]]. Together with ({{convert|21|m|ft|disp=or|adj=mid|-high}}) [[King Ezana's Stele]], the last erected one and the only unbroken, the most famous example of axumite obelisk is the so-called ({{convert|24|m|ft|disp=or|adj=mid|-high}}h) [[Obelisk of Axum]]. It was carved around the 4th century CE and, in the course of time, it collapsed and broke into three parts. In these conditions it was found by Italian soldiers in 1935, after the [[Second Italo-Abyssinian War]], looted and taken to Rome in 1937, where it stood in the Piazza di [[Porta Capena]]. Italy signed a 1947 [[United Nations|UN]] agreement to return the obelisk but did not affirm its agreement until 1997, after years of pressure and various controversial settlements. In 2003 the Italian government made the first steps toward its return, and in 2008 it was finally re-erected.\n\nThe largest known obelisk, the [[Great Stele]] at [[Axum]], now fallen, at {{convert|33|m}} high and {{convert|3|m|abbr=on}} by {{convert|2|m|abbr=on}} at the base ({{convert|520|MT|ST|disp=or}})<ref>{{cite book |title=The Seventy Wonders of the Ancient World |editor=Scarre, Chris |year=1999}}</ref> is one of the largest single pieces of stone ever worked in human history (the largest is either at [[Baalbek]] or the [[Ramesseum]]) and probably fell during erection or soon after, destroying a large part of the massive burial chamber underneath it. The obelisks, properly termed [[stela]]e or the native ''[[hawilt]]'' or ''hawilti'' as they do not end in a pyramid, were used to mark graves and underground burial chambers. The largest of the grave markers were for royal burial chambers and were decorated with multi-storey false windows and false doors, while nobility would have smaller less decorated ones. While there are only a few large ones standing, there are hundreds of smaller ones in "stelae fields".\n\n The Romans commissioned obelisks in an ancient Egyptian style. Examples include:\n*[[Arles]], France \u2013 [[Arles Obelisk]], in Place de la R\u00e9publique, a 4th-century obelisk of [[Ancient Rome|Roman]] origin\n*[[Benevento]], Italy \u2013 [[Domitian]] Obelisk<ref>{{cite web |url=http://www.museodelsannio.com/museo/sezioni/iside/obelisco.htm |title=museodelsannio.com |access-date=21 August 2015 |archive-url=https://web.archive.org/web/20141006075213/http://www.museodelsannio.com/museo/sezioni/iside/obelisco.htm |archive-date=6 October 2014 |url-status=dead}}</ref><ref>{{cite web |url=http://www.obelisks.org/en/benevento.htm |title=Domitian Obelisk (In Piazza Papiniano, Benevento) |website=obelisks.org |access-date=15 September 2019}}</ref>\n*[[Munich]], Germany \u2013 Obelisk of [[Titus Sextius Africanus]], at [[Staatliche Sammlung f\u00fcr \u00c4gyptische Kunst]], 1st century CE, {{convert|5.8|m}}\n*Rome \u2013 there are five, ''see [[List of obelisks in Rome]]''\n\n [[Image:\u00d6rme dikilita\u015f.JPG|thumb|upright|The [[Walled Obelisk]] in [[Istanbul]], [[Turkey]]]]\n*[[Istanbul]], Turkey \u2013 [[Walled Obelisk]], at [[Hippodrome of Constantinople]] (now Sultan Ahmet Square), built by [[Constantine VII]] Porphyrogenitus (905\u2013959) and originally covered with gilded bronze plaques\n\n The prehistoric [[Tello Obelisk]], found in 1919 at ''[[Chav\u00edn de Huantar]]'' in [[Peru]], is a monolith stele with obelisk-like proportions. It is 2.52 metres tall and was carved in a design of low relief with Chav\u00edn symbols, such as bands of teeth and animal heads. Long housed in the ''[[Museo Nacional de Arqueolog\u00eda, Antropolog\u00eda e Historia del Per\u00fa]]'' in [[Lima]], it was relocated to the ''Museo Nacional de Chav\u00edn'', which opened in July 2008. The obelisk was named for the archeologist [[Julio C. Tello]], who discovered it and was considered the 'father of Peruvian archeology'. He was America's first [[Indigenous peoples of the Americas|indigenous]] archeologist.<ref name="iowa">{{cite book |url=http://www.uiowapress.org/books/2009-spring/burger.htm |first=Richard L. |last=Burger |title=The Life and Writings of Julio C. Tello |publisher=University of Iowa Press |access-date=27 September 2010}}</ref>", "Obelisk --- Introduction ---|Modern obelisks": "Egyptian obelisks remain a source of fascination, serving as a reminder of past glories and a symbol of state power. A majority of modern obelisks are made of [[masonry]] or [[concrete]], so not monolithic like their Egyptian counterparts, and are often oversized. Examples from the 19th and 20th centuries include the {{ill|The Stone of the Empress|fi|Keisarinnankivi|lt=Stone of the Empress}} (1835) in [[Helsinki]],<ref>[https://www.myhelsinki.fi/en/see-and-do/sights/the-stone-of-the-empress The Stone of the Empress - My Helsinki]</ref> the [[Wellington Monument, Dublin|Wellington Monument]] (1861) in [[Dublin]], the [[Washington Monument]] (1884) in [[Washington, D.C.]],<ref name=DedicationNYT>[https://timesmachine.nytimes.com/timesmachine/1885/02/22/103628255.pdf Marking a people's love], an article from [[The New York Times]] published February 22, 1885.</ref> the [[Obelisco de Buenos Aires|Obelisk of Buenos Aires]] (1936) in [[Buenos Aires]],<ref name=Lagleyze>Julio A. Luqui Lagleyze, ''Plazas de Buenos Aires'', Revista Todo es Historia, Nro 90, noviembre de 1974</ref> and the [[National Monument (Indonesia)|National Monument]] (1975) in [[Jakarta]]. A few, however, continue the ancient tradition of the monolithic obelisk.\n\n<gallery heights="200" caption="Post-Egyptian obelisks" mode="packed">\nFile:Ireland - Dublin - Phoenix Park - Wellington Monument 2.jpg|The [[Wellington Monument, Dublin|Wellington Monument]] in [[Dublin]], built between 1817 and 1861 to commemorate the victories of [[Arthur Wellesley, 1st Duke of Wellington]]\nFile:Obe brol 1.JPG|The Brothers Broglie Obelisk at the [[Monrepos Park]] in [[Vyborg]], Russia, erected in 1827\nFile:Keisarinnankivihelsinginkauppatorilla.jpg|The {{ill|The Stone of the Empress|fi|Keisarinnankivi|lt=Stone of the Empress}} by [[Carl Ludvig Engel]], erected in 1835 to commemorate Empress [[Alexandra Feodorovna (Charlotte of Prussia)|Alexandra Feodorovna of Russia]], at the [[Market Square, Helsinki|Market Square]] in [[Helsinki]], Finland\nFile: Washington October 2016-6.jpg|The [[Washington Monument]] in [[Washington, D.C.]], built between 1848 and 1884 to commemorate [[George Washington]]\nFile: Obelisk at night.JPG|The [[Obelisco de Buenos Aires|Obelisk of Buenos Aires]], erected in 1936 to commemorate the quadricentennial of the foundation of the city\nFile:Merdeka Square Monas 02.jpg|The [[National Monument (Indonesia)|National Monument]] in [[Jakarta]], built in 1961\u20131975 to commemorate the [[Indonesian National Revolution|struggle for Indonesian independence]]\n</gallery>\n\n In [[Rome]], the [[Via della Conciliazione]], cleared in 1936\u20131950 to link [[Saint Peter's Basilica]] to the centre of the capital is lined with obelisks serving as [[lamppost]]s.\n\nIn France and other European countries, monuments to the dead, such as [[headstone]]s and grave markers, were very often given a form of obelisks, but they are of more modest size. The practice is also still widespread in the [[Islamic world]].\n\nModern obelisks have also been used in [[surveying]] as [[boundary marker]]s.\n\n<gallery heights="200" mode="packed">\nFile:St peters vat distance.jpg|A view from ground level of the [[Via della Conciliazione]] in Rome\nFile:Grab Ludwig van Beethoven Wiener Zentralfriedhof 2020-01-30 21.jpg|Grave of [[Ludwig van Beethoven]] (1770\u20131827) in the central cemetery of [[Vienna]]\nFile:Tombe JEAN BAPTISTE HUBERT \u00e0 YVES --17 --.JPG|Grave of [[Jean-Baptiste Hubert]] (1781\u20131845) in the cemetery of [[Yves, Charente-Maritime]] (France)\nFile:Islamic cemetery in Sarajevo.jpg|Islamic cemetery in [[Sarajevo]], with columnar headstones\n</gallery>\n\n In late summer 1999, Roger Hopkins and [[Mark Lehner]] teamed up with a ''[[Nova (American TV program)|NOVA]]'' crew to erect a 25-ton obelisk. This was the third attempt to erect a 25-ton obelisk; the first two, in 1994 and 1999, ended in failure. There were also two successful attempts to raise a 2-ton obelisk and a 9-ton obelisk. Finally in August\u2013September 1999, after learning from their experiences, they were able to erect one successfully.\n\nFirst Hopkins and Rais Abdel Aleem organized an experiment to tow a block of stone weighing about 25 tons. They prepared a path by embedding wooden rails into the ground and placing a sledge on them bearing a megalith weighing about 25 tons. Initially they used more than 100 people to try to tow it but were unable to budge it. Finally, with well over 130 people pulling at once and an additional dozen using levers to prod the sledge forward, they moved it. Over the course of a day, the workers towed it 10\u201320 feet. Despite problems with broken ropes, they proved the monument could be moved this way.<ref>[https://www.pbs.org/wgbh/nova/egypt/dispatches/990314.html "Dispatches"], NOVA</ref> Additional experiments were done in Egypt and other locations to tow megalithic stone with ancient technologies, some of which are [[List of megalithic sites#List of efforts to move and install stones|listed here]].\n\nOne experiment was to transport a small obelisk on a barge in the Nile River. The barge was built based on ancient Egyptian designs. It had to be very wide to handle the obelisk, with a 2 to 1 ratio length to width, and it was at least twice as long as the obelisk. The obelisk was about {{convert|10|ft|m|order=flip}} long and no more than {{convert|5|MT|ST}}. A barge big enough to transport the largest Egyptian obelisks with this ratio would have had to be close to {{convert|200|ft|m|order=flip|adj=mid|-long}} and {{convert|100|ft|m|order=flip|adj=mid|-wide}}. The workers used ropes that were wrapped around a guide that enabled them to pull away from the river while they were towing it onto the barge. The barge was successfully launched into the Nile.\n\nThe final and successful erection event was organized by Rick Brown, Hopkins, Lehner and Gregg Mullen in a Massachusetts quarry. The preparation work was done with modern technology, but experiments have proven that with enough time and people, it could have been done with ancient technology. To begin, the obelisk was lying on a gravel and stone ramp. A pit in the middle was filled with dry sand. Previous experiments showed that wet sand would not flow as well. The ramp was secured by stone walls. Men raised the obelisk by slowly removing the sand while three crews of men pulled on ropes to control its descent into the pit. The back wall was designed to guide the obelisk into its proper place. The obelisk had to catch a turning groove which would prevent it from sliding. They used brake ropes to prevent it from going too far. Such turning grooves had been found on the ancient pedestals. Gravity did most of the work until the final 15\u00b0 had to be completed by pulling the obelisk forward. They used brake ropes again to make sure it did not fall forward. On 12 September they completed the project.<ref>{{cite web|url=https://www.pbs.org/wgbh/nova/egypt/dispatches/990827.html |title=Mysteries of the Nile | August 27, 1999: The Third Attempt |publisher=Pbs.org |date=27 August 1999 |access-date=14 June 2013}}</ref>\n\nThis experiment has been used to explain how the obelisks may have been erected in Luxor and other locations. It seems to have been supported by a 3,000 year-old [[papyrus]] [[scroll]] in which one scribe taunts another to erect a monument for "thy lord". The scroll reads "Empty the space that has been filled with sand beneath the monument of thy Lord."<ref>[[Nova (American TV program)|NOVA (TV series)]] ''Secrets of Lost Empire II'': "Pharaoh's Obelisks"</ref> To erect the obelisks at Luxor with this method would have involved using over a million cubic meters of stone, mud brick and sand for both the ramp and the platform used to lower the obelisk.<ref>''Time Life Lost Civilizations series: Ramses II: Magnificence on the Nile'', New York: TIME/Life, 1993, pp. 56\u201357</ref> The largest obelisk successfully erected in ancient times weighed {{convert|455|MT|ST}}. A {{convert|520|MT|ST|adj=on}} stele was found in [[Axum]], but researchers believe it was broken while attempting to erect it."}},
{"article_title": "Binaural recording", "pageid": "102676", "revid": "1060018354", "timestamp": "2021-12-13T00:42:04Z", "history_paths": [["Binaural recording --- Introduction ---", "History"]], "categories": ["binaural recordings", "autonomous sensory meridian response", "microphones", "sound recording technology", "stereophonic sound"], "heading_tree": {"Binaural recording --- Introduction ---": {"History": {}, "Recording techniques": {}, "Re-recording techniques": {}, "Playback": {}, "Known issues": {"Timbral issues": {}, "Timbral issues related to headphones": {}}, "Commonly used binaural microphones": {"Br\u00fcel & Kj\u00e6r Head and Torso Simulators (HATS)": {}, "Neumann KU 100": {}, "G.R.A.S. Head & Torso Simulator KEMAR (HATS)": {}, "Core Sound Binaural (CSB) Microphone Set": {}, "3Dio range": {}, "Sound.Codes Kaan": {}, "Sound Professionals SP-TFB-2": {}, "ZiBionic": {}, "Hooke Verse": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Binaural recording --- Introduction ---|History": "The history of binaural recording goes back to 1881.<ref name="Mattana 2017">{{cite web |first=Anthony |last=Mattana |title=The History of Binaural Audio, Part 1: The First Experiments, 1881-1939 |url=https://www.linkedin.com/pulse/history-binaural-audio-part-1-anthony-mattana/ |website=[[LinkedIn]] |date=2017-07-31 |access-date=2021-09-25 }}</ref> The first binaural unit, the [[th\u00e9\u00e2trophone]], was invented by [[Cl\u00e9ment Ader]].<ref name="Mattana 2017" /> It consisted of an array of carbon telephone microphones installed along the front edge of the [[Palais Garnier|Opera Garnier]]. The signal was sent to subscribers through the [[telephone]] system, and required that they wear a special headset, which had a tiny speaker for each ear.\n\nIn 1978, [[Lou Reed]] released the first commercially produced binaural pop record, ''[[Street Hassle]]'', a combination of live and studio recordings.<ref>{{cite news|last=Nusser|first=Dick|title=Arista Has 1st Stereo/Binaural Disk|url=https://books.google.com/books?id=piQEAAAAMBAJ&q=street+hassle+binaural&pg=PP1|access-date=7 April 2014|newspaper=Billboard|date=14 January 1978}}</ref>\n\nBinaural stayed in the background due to the expensive, specialized equipment required for quality recordings, and the requirement of headphones for proper reproduction. Particularly in pre-[[Walkman]] days, most consumers considered headphones an inconvenience, and were only interested in recordings that could be listened to on a home stereo system or in automobiles. Lastly, the types of things that can be recorded do not have a typically high market value. Studio recordings would have little to benefit from using a binaural set up, beyond natural cross-feed, as the spatial quality of the studio would not be very dynamic and interesting. Recordings that are of interest are live [[orchestra]]l performances, and ambient "environmental" recordings of city sounds, nature, and other such subject matters.\n\nThe modern era has seen a resurgence of interest in binaural, partially due to the widespread availability of headphones, cheaper methods of recording and the general increased commercial interest in 360\u00b0 audio technology.\n\nThe online [[ASMR]] community is another movement that has widely employed binaural recordings.\n\nThe rise of [[Dolby Atmos]] and other 360\u00b0 audio film technology in relation to commercial entertainment has seen a rise in popularity of the use of binaural simulation. This is with the purpose of fully adapting the 360\u00b0 soundtrack for headphones and earphones. Users can ostensibly watch 360\u00b0 films and music with the immersive [[surround sound]] experience remaining intact despite using just the two headset speakers. Notably, any full 360\u00b0 multi-channel soundtrack is automatically converted to simulated binaural audio when listened to with headphones.\n\nIn 2020, British film-maker Nicholas Cooley released the short film ''[https://www.imdb.com/title/tt12125712/?ref_=nm_knf_t1  Rear Mirror]'',<ref>https://www.amazon.co.uk/gp/video/detail/B0877TMQM5 ''Prime Video'', Retrieved 15 May 2020.</ref><ref>{{cite web |url=https://www.imdb.com/event/ev0013701/2020/1/ |title=New York Movie Awards on IMBD |website=[[IMDb]] |access-date=15 May 2020 }}</ref> which was the first binaural sound film to be featured on a video on demand platform ([[Amazon Prime Video]]).<ref>https://www.imdb.com/title/tt12125712/?ref_=nm_knf_t1 '' IMBD'', Retrieved 14 May 2020.</ref>\n\nIn 2021, British singer-songwriter Anna Aarons released the single ''[https://open.spotify.com/track/2A6WjoPbpzbeMYtklJVrgb A Perfect Day]'' in binaural format.<ref>{{cite AV media |people=Anna Aarons |date=2021-08-06 |title=A Perfect Day (Binaural 3D Mix) |type=Video |url=https://www.youtube.com/watch?v=tnv9_scfEUE | archive-url=https://ghostarchive.org/varchive/youtube/20211211/tnv9_scfEUE| archive-date=2021-12-11 | url-status=live|access-date=2021-09-28 |location= |publisher=Horus Music }}{{cbignore}}</ref>"}},
{"article_title": "Remote control", "pageid": "105803", "revid": "1060245633", "timestamp": "2021-12-14T08:59:18Z", "history_paths": [["Remote control --- Introduction ---", "History"]], "categories": ["remote control", "british inventions", "assistive technology", "consumer electronics", "human\u2013machine interaction", "infrared technology"], "heading_tree": {"Remote control --- Introduction ---": {"History": {"Television remote controls": {}, "Other remote controls": {}, "Proliferation": {}}, "Technique": {"Opto components and circuits": {}, "Consumer electronics infrared protocols": {}, "Infrared, line of sight and operating angle": {}, "Radio remote control systems": {}}, "Usage": {"Industry": {}, "Garage and gate": {}, "Military": {}, "Space": {}, "PC control": {}, "Photography": {}, "Video games": {}}, "Standby power": {}, "Alternatives": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Remote control --- Introduction ---|History": "{{See|Radio control#History}}\nWired and wireless remote control was developed in the latter half of the 19th century to meet the need to control unmanned vehicles (for the most part military torpedoes).<ref>H. R. Everett, Unmanned Systems of World Wars I and II, MIT Press - 2015, pages 79-80</ref> These included a wired version by German engineer [[Werner von Siemens]] in 1870, and radio controled ones by British engineer Ernest Wilson and C. J. Evans (1897)<ref>H. R. Everett, Unmanned Systems of World Wars I and II, MIT Press - 2015, page 87</ref><ref>{{Cite book|url=https://books.google.com/books?id=fNjgCgAAQBAJ&q=Wilson+1897+Torpedo&pg=PA87|title=Unmanned Systems of World Wars I and II|isbn=9780262029223|last1=Everett|first1=H. R.|date=6 November 2015}}</ref> and a prototype that inventor [[Nikola Tesla]] demonstrated in New York in 1898.<ref>[[Tapan K. Sarkar]], '' History of wireless'', John Wiley and Sons, 2006, {{ISBN|0-471-71814-9}}, p. 276-278.</ref> In 1903 Spanish engineer [[Leonardo Torres y Quevedo]] demonstrated a radio controlled boat using a system called "''Telekino''", which he hoped to use to control a [[Astra-Torres airship|dirigible airship of his own design]].<ref>Sarkar 2006, page 97</ref><ref>H. R. Everett, Unmanned Systems of World Wars I and II, MIT Press - 2015, pages 91-95</ref> The first remote-controlled model airplane flew in 1932,{{fact|date=November 2021}} and the use of remote control technology for military purposes was worked on intensively during the [[Second World War]], one result of this being the German [[Wasserfall missile]].\n\n[[File:PhilcoMysteryRadioRemoteControl CBCMuseum.png|thumb|[[Philco]] Mystery Control (1939)]]\n\nBy the late 1930s, several radio manufacturers offered remote controls for some of their higher-end models.<ref>{{cite web|url=https://books.google.com/books?id=xSgDAAAAMBAJ&q=Popular+Science+1931+plane&pg=PA78|title=Radio Aims At Remote Control|date=November 1930|work=Popular Science|publisher=Bonnier Corporation}}</ref> Most of these were connected to the set being controlled by wires, but the [[Philco]] Mystery Control (1939) was a battery-operated low-frequency radio transmitter,<ref>{{cite web |url=http://www.philcorepairbench.com/mystery/index.htm|title=Philco Mystery Control}}</ref> thus making it the first wireless remote control for a consumer electronics device.  Using pulse-count modulation, this also was the first digital wireless remote control.\n\n [[File:Circa 1950's Television Remote Control made by Motorola.jpg|thumb|1950s TV Remote by Motorola]]\n[[File:SABA-corded-TV-remote-left.jpg|thumb|alt=A photo of a SABA TV remote with cord attached|[[SABA (electronics manufacturer)|SABA]] corded TV remote]]\nThe first remote intended to control a television was developed by [[Zenith Electronics Corporation|Zenith Radio Corporation]] in 1950. The remote, called "Lazy Bones,"<ref name="metv.com">{{cite web|url=https://www.metv.com/stories/a-history-of-the-television-remote-control-as-told-through-its-advertising|title=A history of the TV remote control as told through its advertising|website=Me-TV Network|access-date=17 August 2018}}</ref> was connected to the [[television]] by a wire. A wireless remote control, the "Flashmatic,"<ref name="metv.com"/><ref>{{cite web|url=https://www.zenith.com/remote-background/|title=Remote Background - Zenith Electronics|website=zenith.com|access-date=17 August 2018}}</ref> was developed in 1955 by [[Eugene Polley]]. It worked by shining a beam of light onto one of four [[Solar cell|photoelectric cells]],<ref>{{cite web|url=https://www.cnet.com/pictures/remembering-eugene-polley-and-his-flash-matic-remote-photos/|title=Remembering Eugene Polley and his Flash-Matic remote (photos)|date=23 May 2012|website=cnet.com|access-date=17 August 2018}}</ref> but the cell did not distinguish between light from the remote and light from other sources.<ref name="theregister.co.uk">{{cite web|url=https://www.theregister.co.uk/2012/05/23/remote_control_inventor_eugene_polley/|title=Wireless remote control inventor zaps out at 96|website=theregister.co.uk|access-date=17 August 2018}}</ref> The Flashmatic also had to be pointed very precisely at one of the sensors in order to work.<ref name="theregister.co.uk"/><ref>{{cite web |url=http://www.zenith.com/sub_about/about_remote.html |archive-url=https://web.archive.org/web/20080116212531/http://www.zenith.com/sub_about/about_remote.html |archive-date=January 16, 2008 |title=Five Decades of Channel Surfing: History of the TV Remote Control |access-date=December 3, 2008}}</ref>\n\n[[Image:Zenith Space Commander 600.jpg|thumb|200px|right|The ''Zenith Space Commander Six hundred'' remote control]]\nIn 1956, [[Robert Adler]] developed<ref>{{cite web|url=https://patents.google.com/patent/US2817025A/en|title=Control system (US patent 2817025A)|author=Robert Adler|website=google.com|access-date=17 August 2018}}</ref> "Zenith Space Command,"<ref name="metv.com"/> a wireless remote.<ref name=Farhi>Farhi, Paul. [https://web.archive.org/web/20180817031653/http://www.washingtonpost.com/wp-dyn/content/article/2007/02/16/AR2007021602102.html "The Inventor Who Deserves a Sitting Ovation."] ''Washington Post''. February 17, 2007.</ref> It was mechanical and used ultrasound to change the channel and volume.<ref>{{cite news|url=https://www.nytimes.com/2007/12/30/magazine/30Adler-t.html|title=The Lives They Lived - Robert Adler - Remote Control - Television|first=Jon|last=Gertner|newspaper=The New York Times|date=December 30, 2007|access-date=17 August 2018}}</ref> When the user pushed a button on the remote control, it struck a bar and clicked, hence they were commonly called a "clicker," but it sounded like a "clink" and the mechanics were similar to a [[plectrum|pluck]].<ref>{{cite magazine|url=https://www.wired.com/2007/10/vg-greatestgadget/|title=1956: Zenith Space Commander Remote Control|magazine=Wired|access-date=17 August 2018}}</ref> Each of the four bars emitted a different fundamental frequency with ultrasonic harmonics, and circuits in the television detected these sounds and interpreted them as channel-up, channel-down, sound-on/off, and power-on/off.<ref>{{cite web|url=https://lemelson.mit.edu/resources/robert-adler|title=Robert Adler -TV wireless remote|publisher=MIT |access-date=13 April 2021}}</ref>\n\nLater, the rapid decrease in price of [[transistor]]s made possible cheaper [[electronics|electronic]] remotes that contained a [[Piezoelectricity|piezoelectric]] crystal that was fed by an [[Oscillation|oscillating]] electric current at a [[frequency]] near or above the upper threshold of [[Hearing (sense)|human hearing]], though still audible to [[dog]]s. The receiver contained a [[microphone]] attached to a circuit that was tuned to the same frequency. Some problems with this method were that the receiver could be triggered accidentally by naturally occurring noises or deliberately by metal against glass, for example, and some people could hear the lower ultrasonic harmonics.\n\n[[File:RCA RCU403.jpg|thumb|150px|An [[RCA]] universal remote]]\nIn 1970, [[RCA]] introduced an all-electronic remote control that uses [[digital signals]] and [[metal\u2013oxide\u2013semiconductor field-effect transistor]] (MOSFET) [[semiconductor memory|memory]]. This was widely adopted for [[color television]], replacing motor-driven tuning controls.<ref>{{cite journal |title=Remote control for color tv goes the all-electronic route |journal=[[Electronics (magazine)|Electronics]] |date=April 1970 |volume=43 |page=102 |url=https://books.google.com/books?id=rFJJAQAAIAAJ |publisher=McGraw-Hill Publishing Company |quote=RCA's Wayne Evans, Carl Moeller and Edward Milbourn tell how digital signals and MOS FET memory modules are used to replace motor-driven tuning controls}}</ref>\n\nThe impetus for a more complex type of television remote control came in 1973, with the development of the [[Ceefax]] [[teletext]] service by the [[BBC]]. Most commercial remote controls at that time had a limited number of functions, sometimes as few as three: next channel, previous channel, and volume/off. This type of control did not meet the needs of Teletext sets, where pages were identified with three-digit numbers. A remote control that selects Teletext pages would need buttons for each numeral from zero to nine, as well as other control functions, such as switching from text to picture, and the normal television controls of volume, channel, brightness, color intensity, etc. Early Teletext sets used wired remote controls to select pages, but the continuous use of the remote control required for Teletext quickly indicated the need for a wireless device. So BBC engineers began talks with one or two television manufacturers, which led to early prototypes in around 1977\u20131978 that could control many more functions. [[ITT Corporation|ITT]] was one of the companies and later gave its name to the ITT protocol of infrared communication.<ref>{{cite web|url=http://www.sbprojects.com/knowledge/ir/itt.php |title=SB-Projects: IR remote control: ITT protocol}}</ref>\n\n[[Image:Remote controls.JPG|thumb|center|680px|[[TV]], [[VHS]] and [[DVD]] Remote controls]]\nIn 1980, the most popular remote control was the ''Starcom Cable TV Converter''<ref>{{cite web|url=http://theoldcatvequipmentmuseum.org/170/173/1731/index.html|title=1731|website=theoldcatvequipmentmuseum.org|access-date=17 August 2018}}</ref> (from [[Jerrold Electronics]], a division of [[General Instrument]])<ref name="metv.com"/> which used 40-kHz sound to change channels. Then, a Canadian company, Viewstar, Inc., was formed by engineer Paul Hrivnak and started producing a cable TV [[Cable converter box|converter]] with an infrared remote control. The product was sold through Philips for approximately $190 [[Canadian dollar|CAD]]. The Viewstar converter was an immediate success, the millionth converter being sold on March 21, 1985, with 1.6 million sold by 1989.<ref>{{cite web|url=https://tedium.co/2017/05/25/universal-remote-control-history/|title=Universal Remote Control History: Not Great, Just Good Enough|date=26 May 2017|website=tedium.co|access-date=17 August 2018}}</ref><ref>"Philips tops in converters". ''The Toronto Star'': p. F03. November 29, 1980.</ref>\n\n The Blab-off was a wired remote control created in 1952 that turned a TV's (television) sound on or off so that viewers could avoid hearing commercials.<ref>{{cite web|url=http://www.earlytelevision.org/blab_off.html|title=Blab-Off|work=earlytelevision.org}}</ref> In the 1980s [[Steve Wozniak]] of [[Apple Inc.|Apple]] started a company named [[CL 9]]. The purpose of this company was to create a remote control that could operate multiple electronic devices. The CORE unit (Controller Of Remote Equipment) was introduced in the fall of 1987. The advantage to this remote controller was that it could "learn" remote signals from different devices. It had the ability to perform specific or multiple functions at various times with its built-in clock. It was the first remote control that could be linked to a computer and loaded with updated software code as needed. The CORE unit never made a huge impact on the market. It was much too cumbersome for the average user to program, but it received rave reviews from those who could.{{citation needed|date=December 2011}} These obstacles eventually led to the demise of CL 9, but two of its employees continued the business under the name Celadon. This was one of the first computer-controlled learning remote controls on the market.<ref>{{cite web|url=http://www.celadon.com/Profile/Profile.html|title=Celadon Remote Control Systems Company Profile Page}}</ref>\n\nIn the 1990s, cars were increasingly sold with electronic remote control door locks. These remotes transmit a signal to the car which locks or unlocks the door locks or unlocks the trunk. An aftermarket device sold in some countries is the remote starter. This enables a car owner to remotely start their car. This feature is most associated with countries with winter climates, where users may wish to run the car for several minutes before they intend to use it, so that the car heater and defrost systems can remove ice and snow from the windows.\n\n [[File:Remote Controls for sale in Hong Kong.JPG|thumb|right|300px|Used remote controls for sale in a market in [[Hong Kong]].]]\nBy the early 2000s, the number of consumer electronic devices in most homes greatly increased, along with the number of remotes to control those devices. According to the [[Consumer Electronics Association]], an average US home has four remotes.{{citation needed|date=December 2011}} To operate a [[home cinema|home theater]] as many as five or six remotes may be required, including one for cable or satellite receiver, [[VCR]] or [[digital video recorder]] (DVR/PVR), [[DVD player]], [[Television|TV]] and [[audio amplifier]]. Several of these remotes may need to be used sequentially for some programs or services to work properly. However, as there are no accepted interface guidelines, the process is increasingly cumbersome. One solution used to reduce the number of remotes that have to be used is the [[universal remote]], a remote control that is programmed with the operation codes for most major brands of TVs, DVD players, etc. In the early 2010s, many [[smartphone]] manufacturers began incorporating infrared emitters into their devices, thereby enabling their use as universal remotes via an included or downloadable [[Mobile app|app]].<ref>{{cite web|last1=Seifert|first1=Dan|title=Back from the dead: why do 2013's best smartphones have IR blasters?|url=https://www.theverge.com/2013/4/24/4262074/is-this-the-year-of-the-ir-blaster|website=The Verge|date=April 24, 2013|access-date=28 December 2015}}</ref>"}},
{"article_title": "Library (computing)", "pageid": "106421", "revid": "1061985040", "timestamp": "2021-12-25T11:22:38Z", "history_paths": [["Library (computing) --- Introduction ---", "History"]], "categories": ["computer libraries", "operating system technology"], "heading_tree": {"Library (computing) --- Introduction ---": {"History": {}, "{{anchor|Smart linking}}Linking": {}, "Relocation": {}, "Static libraries": {}, "Shared libraries": {"Memory sharing": {}, "Dynamic linking": {}, "Optimizations": {}, "Locating libraries at runtime": {"Microsoft Windows": {}, "OpenStep": {}, "Unix-like systems": {}}, "Dynamic loading": {}}, "Object libraries": {}, "Class libraries": {}, "Remote libraries": {}, "Code generation libraries": {}, "File naming": {"Most modern Unix-like systems": {}, "macOS": {}, "Microsoft Windows": {}}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Library (computing) --- Introduction ---|History": "[[File:FirstCodeLibrary-ESDAC-ThePreparationOfProgramsForAnElectronicDigitalComputer-1951.jpg|thumb|A woman working next to a filing cabinet containing the subroutine library on reels of punched tape for the EDSAC computer.]]\n\nIn 1947 [[Herman Goldstine|Goldstine]] and [[John von Neumann|von Neumann]] speculated that it would be useful to create a "library" of [[subroutine]]s for their work on the [[IAS machine]], an early computer that was not yet operational at that time.<ref>{{Cite book|last=Goldstine|first=Herman H.|url=http://dx.doi.org/10.1515/9781400820139|title=The Computer from Pascal to von Neumann|date=2008-12-31|publisher=Princeton University Press|isbn=978-1-4008-2013-9|location=Princeton|doi=10.1515/9781400820139}}</ref> They envisioned a physical library of [[magnetic wire recording]]s, with each wire storing reusable computer code.<ref>{{cite report |last1=Goldstine |first1=Herman |last2=von Neumann |first2=John |author-link1=Herman Goldstine |author-link2=John von Neumann |date=1947 |title=Planning and coding of problems for an electronic computing instrument |url= |publisher=Institute for Advanced Study |page=3, 21\u201322 |oclc=26239859 |quote=it will probably be very important to develop an extensive "library" of subroutines}}</ref>\n\nInspired by von Neumann, [[Maurice Wilkes|Wilkes]] and his team constructed [[EDSAC]]. A [[filing cabinet]] of [[punched tape]] held the subroutine library for this computer.<ref>{{Cite conference|last=Wilkes|first=M. V.|date=1951|title=The EDSAC Computer|url=http://dx.doi.org/10.1109/afips.1951.13|conference=1951 International Workshop on Managing Requirements Knowledge|publisher=IEEE|doi=10.1109/afips.1951.13}}</ref> Programs for EDSAC consisted of a main program and a sequence of subroutines copied from the subroutine library.<ref>{{cite journal |last1=Campbell-Kelly |first1=Martin |date=September 2011 |title=In Praise of 'Wilkes, Wheeler, and Gill' |url=https://cacm.acm.org/magazines/2011/9/122802-in-praise-of-wilkes-wheeler-and-gill/fulltext |journal=Communications of the ACM |volume=54 |issue=9 |pages=25\u201327 |doi=10.1145/1995376.1995386|s2cid=20261972 }}</ref> In 1951 the team published the first textbook on programming, ''[[The Preparation of Programs for an Electronic Digital Computer]]'', which detailed the creation and the purpose of the library.<ref>{{cite book |last1=Wilkes |first1=Maurice |last2=Wheeler |first2=David |last3=Gill |first3=Stanley |author-link1=Maurice Wilkes |author-link2=David Wheeler (computer scientist) |author-link3=Stanley Gill |date=1951 |title=The Preparation of Programs for an Electronic Digital Computer |oclc=641145988 |url=https://archive.org/details/programsforelect00wilk/page/80/mode/2up?q=library |location= |publisher=Addison-Wesley |page=45, 80\u201391, 100 |isbn=}}</ref>\n\n[[COBOL]] included "primitive capabilities for a library system" in 1959,<ref name="Wexelblat_1981_247">{{Cite book |last=Wexelblat |first=Richard |title=History of Programming Languages |publisher=Academic Press (A subsidiary of [[Harcourt Brace]]) |year=1981 |series=ACM Monograph Series |publication-place=New York, NY |isbn=0-12-745040-8 |page=[https://archive.org/details/historyofprogram0000hist/page/274 274] |url=https://archive.org/details/historyofprogram0000hist/page/274 }}</ref> but [[Jean E. Sammet|Jean Sammet]] described them as "inadequate library facilities" in retrospect.<ref name="Wexelblat_1981_258">Wexelblat, ''op. cit.'', p. 258</ref>\n\n[[JOVIAL]] had a Communication Pool (COMPOOL), roughly a library of header files.\n\nAnother major contributor to the modern library concept came in the form of the [[subprogram]] innovation of [[FORTRAN]]. FORTRAN subprograms can be compiled independently of each other, but the compiler lacked a [[Linker (computing)|linker]]. So prior to the introduction of modules in Fortran-90, [[type checking]] between FORTRAN<ref group=NB>It was possible earlier between, e.g., Ada subprograms.</ref> subprograms was impossible.<ref name="Wilson_Clark_1988_126">{{Cite book |last1=Wilson |first1=Leslie B. |last2=Clark |first2=Robert G.\n|title=Comparative Programming Languages\n|publisher=Addison-Wesley |year=1988 |publication-place=Wokingham, England |isbn=0-201-18483-4 |page=126 }}</ref>\n\nBy the mid 1960s, copy and macro libraries for assemblers were common. Starting with the popularity of the [[IBM System/360]], libraries containing other types of text elements, e.g., system parameters, also became common.\n\n[[Simula]] was the first [[object-oriented programming]] language, and its [[Class (computer science)|classes]] were nearly identical to the modern concept as used in [[Java (programming language)|Java]], [[C++]], and [[C Sharp (programming language)|C#]]. The ''class'' concept of Simula was also a progenitor of the ''package'' in [[Ada (programming language)|Ada]] and the ''module'' of [[Modula-2]].<ref name="Wilson_Clark_1988_52">Wilson and Clark, ''op. cit.'', p. 52</ref> Even when developed originally in 1965, Simula classes could be included in library files and added at compile time.<ref name="Wexelblat_1981_716">Wexelblat, ''op. cit.'', p. 716</ref>"}},
{"article_title": "Unijunction transistor", "pageid": "108824", "revid": "1054989048", "timestamp": "2021-11-13T04:46:29Z", "history_paths": [["Unijunction transistor --- Introduction ---", "Applications"], ["Unijunction transistor --- Introduction ---", "Invention"]], "categories": ["transistor types", "general electric inventions", "1953 in technology"], "heading_tree": {"Unijunction transistor --- Introduction ---": {"Types": {}, "Applications": {}, "Construction": {}, "Device operation": {}, "Invention": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Unijunction transistor --- Introduction ---|Applications": "Unijunction transistor circuits were popular in hobbyist electronics circuits in the 1960s and 1970s because they allowed simple [[oscillator]]s to be built using just one active device. For example, they were used for [[relaxation oscillator]]s in variable-rate strobe lights.<ref>\n{{cite journal\n | journal = Popular Science\n | title = A Repeating Flash You Can Build\n | author = Ronald M. Benrey\n | volume = 185\n | issue = 4\n | pages = 132\u2013136\n | date = October 1964\n | url = https://books.google.com/books?id=1yUDAAAAMBAJ&pg=PA132\n }}</ref>\nLater, as [[integrated circuit]]s became more popular, oscillators such as the [[555 timer IC]] became more commonly used.\n\nIn addition to its use as the active device in relaxation oscillators, one of the most important applications of UJTs or PUTs is to trigger [[thyristor]]s ([[silicon controlled rectifier]]s (SCR), [[TRIAC]], etc.). A DC voltage can be used to control a UJT or PUT circuit such that the "on-period" increases with an increase in the DC control voltage. This application is important for large AC current control.\n\nUJTs can also be used to measure magnetic flux. The [[hall effect]] modulates the voltage at the PN junction. This affects the frequency of UJT relaxation oscillators.<ref>{{cite journal\n|last1=Agrawal\n|first1=S. L.\n|last2=Saha\n|first2=D. P.\n|last3=Swami\n|first3=R.\n|last4=Singh\n|first4=R. P.\n|title=Digital magnetic fluxmeter using unijunction transistor probe\n|journal=International Journal of Electronics\n|date=23 April 1987\n|volume=63\n|issue=6\n|pages=905\u2013910\n|doi=10.1080/00207218708939196\n}}</ref> This only works with UJTs. PUTs do not exhibit this phenomenon.", "Unijunction transistor --- Introduction ---|Invention": "The unijunction transistor was invented as a byproduct of research on [[germanium]] tetrode transistors at [[General Electric]].<ref>{{cite web|url=http://www.semiconductormuseum.com/Transistors/GE/OralHistories/Suran/Suran_Index.htm|title=Transistor Museum Oral History Suran Index GE Unijunction Transistors|author=Jack Ward|date=2005|work=SemiconductorMuseum.com|access-date=April 10, 2017}}</ref> It was patented in 1953. Commercially, silicon devices were manufactured.<ref>{{cite web|url=https://sites.google.com/site/transistorhistory/Home/us-semiconductor-manufacturers/general-electric-history|title=General Electric  History - Transistor History|work=Google.com|access-date=April 10, 2017}}</ref> A common part number is 2N2646."}},
{"article_title": "Adze", "pageid": "113276", "revid": "1050162673", "timestamp": "2021-10-16T05:17:12Z", "history_paths": [["Adze --- Introduction ---", "History"]], "categories": ["archaeological artefact types", "egyptian artefact types", "green woodworking tools", "lithics", "primitive technology", "woodworking hand tools"], "heading_tree": {"Adze --- Introduction ---": {"History": {"Africa": {}, "New Zealand": {}, "Northwest Coastal America": {}, "New Guinea and Melanesia": {}}, "Modern adzes": {"Foot adze": {}, "Hand adze": {}}, "See also": {}, "Footnotes and references": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Adze --- Introduction ---|History": "The adze is depicted in ancient Egyptian art from the [[Old Kingdom]] onward.<ref>{{cite book \n  |quote=A statue of the third dynasty boat builder Ankhwah is showing him holding an adze \n  |author =Rice M \n  |title=Who's who in ancient Egypt \n  |publisher=Routledge |location=New York \n  |year=1999 \n  |pages=25 \n  |isbn=0-415-15448-0 \n}}</ref> Originally the adze blades were made of stone, but already in the [[Predynastic Egypt|Predynastic Period]] copper adzes had all but replaced those made of flint.<ref>{{cite book |vauthors =Shubert SB, Bard KA |title=Encyclopedia of the archaeology of ancient Egypt |url =https://archive.org/details/encyclopediaarch00bard |url-access =limited |publisher=Routledge |location=New York |year=1999 |pages=[https://archive.org/details/encyclopediaarch00bard/page/n510 458] |isbn=0-415-18589-0 }}</ref> While stone blades were fastened to the wooden handle by tying, metal blades had sockets into which the handle was fitted. Examples of Egyptian adzes can be found in museums and on the Petrie Museum website.\n\n{{Hiero|Adze-on-Block|<hiero>U21</hiero>|align=right|era=egypt}}\nA [[adze-on-block (hieroglyph)|depiction of an adze]] was also used as a [[Egyptian hieroglyphs|hieroglyph]], representing the consonants ''stp'', "chosen", and used as: ''...Pharaoh XX, chosen of God/Goddess YY...''\n\nThe ''ahnetjer'' ([[Manuel de Codage]] transliteration: ''aH-nTr'') depicted as an adze-like instrument,<ref>{{cite book |title=W\u00f6rterbuch der \u00e4gyptischen Sprache [Dictionary of the Egyptian language] |vauthors =Erman A, Grapow H |year=1926 |publisher=JC Hinrichs |location=Leipzig |volume=1 |pages=214.24 }}</ref> was used in the [[Opening of the mouth ceremony|Opening of the Mouth ceremony]], intended to convey power over their senses to statues and mummies. It was apparently the [[foreleg of ox|foreleg]] of a freshly sacrificed bull or cow with which the mouth was touched.<ref>{{cite book |vauthors =Schwabe CW, Gordon A |title=The quick and the dead: biomedical theory in ancient Egypt |publisher=Brill |location=Leiden |year=2004 |pages=76 |isbn=90-04-12391-1 }}</ref><ref>{{cite book |author =Eyre C |title=The cannibal hymn: a cultural and literary study |publisher=Liverpool University Press |location=Liverpool |year=2002 |pages=54 |isbn=0-85323-706-9 }}</ref>\n\nAs [[Iron Age]] technology moved south into [[Africa]] with migrating ancient Egyptians{{Citation needed|date=February 2015}}, they carried their technology with them, including adzes. To this day, iron adzes are used all over rural Africa for various purposes - from digging pit latrines, and chopping firewood, to tilling crop fields - whether they are of maize (corn), coffee, tea, pyrethrum, beans, Millett, yams or a plethora of other cash and subsistence crops.\n\n Prehistoric [[M\u0101ori culture|M\u0101ori]] adzes from [[New Zealand]] (called ''toki'' in [[M\u0101ori language|M\u0101ori]]) were for [[wood carving]], typically made from [[pounamu]] sourced from the South Island.<ref name="Kneebone">{{Cite journal| doi = 10.1002/arco.5193| issn = 1834-4453| volume = 54| issue = 3| pages = 163\u2013172| last1 = Kneebone| first1 = Brendan| last2 = Mcalister| first2 = Andrew| title = Addressing models of Maori interaction and regional variation in New Zealand: an analysis of stone adzes from the Auckland (Tamaki) region| journal = Archaeology in Oceania| access-date = 2021-01-14| date = 2019| url = https://onlinelibrary.wiley.com/doi/abs/10.1002/arco.5193}}</ref> During the [[M\u0101ori history|M\u0101ori Archaic period]] found on the North Island were commonly made from [[greywacke]] from [[Motutapu Island]] or [[basalt]] from \u014cpito Bay in the [[Coromandel Peninsula|Coromandel]], similar to adzes constructed on other Pacific Islands.<ref name="Kneebone"/> Early period notched adzes found in [[Northland Region|Northland]] were primarily made of [[argillite]] quarried from locations around the [[Marlborough Region|Marlborough]] and [[Nelson, New Zealand|Nelson]] regions.<ref>{{Cite journal| issn = 1174-9202| volume = 49| pages = 5\u201313| last = Furey| first = Louise| title = Adzes with notches| journal = [[Auckland War Memorial Museum|Records of the Auckland Museum]] | access-date = 2021-01-14| date = 2014| url = https://www.aucklandmuseum.com/getmedia/40fe1acc-fa75-45b8-9dda-4f2f3c427edd/records-of-the-auckland-museum-vol-49-2014}}</ref> At the same time on [[Henderson Island (Pitcairn Islands)|Henderson Island]], a small coral island in eastern [[Polynesia]] lacking any rock other than [[limestone]], native populations may have fashioned giant clamshells into adzes.<ref>{{cite book |last=Diamond|first=Jared |title=Guns, Germs, and Steel |publisher= Norton |location=New York, N.Y. |year=1997 |page=67 |isbn=0-393-31755-2}}</ref>\n\n [[File: Native Alaskan boat builder.jpg|thumb|Native Alaskan boat builder using an adze]]\nAmerican Northwest coast native peoples traditionally used adzes for both functional construction (from bowls to canoes) and art (from masks to totem poles).  Northwest coast adzes take two forms: hafted and D-handle.  The hafted form is similar in form to a European adze with the haft constructed from a natural crooked branch which approximately forms a 60% angle.  The thin end is used as the handle and the thick end is flattened and notched such that an adze iron can be lashed to it. Modern hafts are sometimes constructed from a sawed blank with a dowel added for strength at the crook.  The second form is the D-handle adze which is basically an adze iron with a directly attached handle.  The D-handle, therefore, provides no mechanical leverage.  Northwest coast adzes are often classified by size and iron shape vs. role.  As with European adzes, iron shapes include straight, gutter and lipped.  Where larger Northwest adzes are similar in size to their European counterparts, the smaller sizes are typically much lighter such that they can be used for the detailed smoothing, shaping and surface texturing required for figure carving.  Final surfacing is sometimes performed with a [[crooked knife]].{{Citation needed|date=August 2010}}\n\n [[File:Adzes from New Guinea.jpg|thumb|140px|right|Contemporary stone adzes from New Guinea]]\nGround stone adzes are still in use by a variety of people in [[Irian Jaya]] (Indonesia), [[Papua New Guinea]] and some of the smaller Islands of [[Melanesia]] and [[Micronesia]]. The hardstone is ground on a riverine rock with the help of water until it has got the desired shape. It is then fixed to a natural grown angled wood with resin and plant fibers. The shape and manufacture of these adzes is similar to those found from the Neolithic Stone Age in Europe. A variety of minerals are used. Their everyday use is on a steady decline, as it is much more convenient to cut firewood using imported steel axes or [[machete]]s. However, certain ceremonial crafts such as making canoes, ceremonial shields, masks, drums, containers or communal houses etc. may require the use of traditional-made stone adzes.\n\n<gallery widths="200px" heights="200px">\nFile:19th century knowledge woodworking adze and axe.jpg|19th century knowledge woodworking adze and axe\nFile:Making paddle with adze, Tobi, Western Caroline Islands, Micronesia.jpg|Micronesian of [[Tobi (island)|Tobi]], [[Palau]], making a paddle for his ''[[Wa (watercraft)|wa]]'' with an adze\nFile:WLA brooklynmuseum Boat Building Scene 2.jpg|Egyptian boat-building relief, featuring a workman using an adze\nFile:Adzes, Marshall and Yap Islands - Pacific collection - Peabody Museum, Harvard University - DSC05732.JPG|Adzes, Marshall and Yap Islands - Pacific collection - [[Peabody Museum of Archaeology and Ethnology|Peabody Museum]], Harvard University - DSC05732\nFile:19th century knowledge carpentry and woodworking japanese adze.jpg|Japanese adze.\nFile:Rye Shipyard- the Construction of Motor Fishing Vessels, Rye, Sussex, England, UK, 1944 D22783.jpg|Rye Shipyard- the Construction of Motor Fishing Vessels, Rye, Sussex, England, UK, 1944 D22783\nFile:SainteMarieAmongTheHuronsAdze.jpg|A craftsman uses an adze to square beams, and to recreate 17th-century colonial life.\n</gallery>"}},
{"article_title": "Geothermal energy", "pageid": "113728", "revid": "1063145907", "timestamp": "2022-01-01T14:20:48Z", "history_paths": [["Geothermal energy --- Introduction ---", "History"]], "categories": ["geothermal energy", "power station technology", "sustainable energy", "volcanism", "earth"], "heading_tree": {"Geothermal energy --- Introduction ---": {"History": {}, "Resources": {}, "Geothermal power": {}, "Geothermal heating": {}, "Types": {"Liquid-dominated plants": {}, "Enhanced geothermal systems": {}}, "Economics": {}, "Renewability and sustainability": {}, "Environmental effects": {}, "Production": {}, "Legal frameworks": {}, "See also": {}, "References": {}, "Bibliography": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Geothermal energy --- Introduction ---|History": "[[File:Oldest geothermal.jpg|thumb|right|The oldest known pool fed by a hot spring, built in the [[Qin dynasty]] in the 3rd century BCE]]\n[[Hot spring]]s have been used for bathing at least since [[Paleolithic]] times.<ref>{{Citation| last = Cataldi | first = Raffaele| date =August 1992| title =Review of historiographic aspects of geothermal energy in the Mediterranean and Mesoamerican areas prior to the Modern Age| periodical =Geo-Heat Centre Quarterly Bulletin| location =Klamath Falls, Oregon| publisher =Oregon Institute of Technology| volume =18| issue =1| pages = 13\u201316| url =http://geoheat.oit.edu/pdf/bulletin/bi046.pdf| access-date =2009-11-01}}</ref> The oldest known spa is a stone pool on China's Lisan mountain built in the [[Qin Dynasty]] in the 3rd century BCE, at the same site where the Huaqing Chi palace was later built. In the first century CE, Romans conquered ''[[Aquae Sulis]]'', now [[Bath, Somerset]], England, and used the hot springs there to feed [[thermae|public baths]] and [[hypocaust|underfloor heating]]. The admission fees for these baths probably represent the first commercial use of geothermal power. The world's oldest geothermal district heating system in [[Chaudes-Aigues]], France, has been operating since the 15th century.<ref name="utilization">{{Citation| last = Lund | first = John W.| date =June 2007| title =Characteristics, Development and utilization of geothermal resources| periodical =Geo-Heat Centre Quarterly Bulletin| location =Klamath Falls, Oregon| publisher =Oregon Institute of Technology| volume =28| issue =2| pages = 1\u20139| url =http://geoheat.oit.edu/bulletin/bull28-2/art1.pdf| access-date =2009-04-16}}</ref> \nThe earliest industrial exploitation began in 1827 with the use of geyser steam to extract [[boric acid]] from [[volcanic mud]] in [[Larderello]], Italy.\n\nIn 1892, America's first [[district heating]] system in [[Boise, Idaho]] was powered directly by geothermal energy, and was copied in [[Klamath Falls, Oregon]] in 1900. The first known building in the world to utilize geothermal energy as its primary heat source was the [[Hot Lake Hotel]] in [[Union County, Oregon]], whose construction was completed in 1907.{{sfn|Cleveland|Morris|2015|p=291}} A deep geothermal well was used to heat greenhouses in Boise in 1926, and geysers were used to heat greenhouses in Iceland and [[Tuscany]] at about the same time.<ref name="Dickson">{{Citation\n |last1 = Dickson\n |first1 = Mary H.\n |last2 = Fanelli\n |first2 = Mario\n |date = February 2004\n |title = What is Geothermal Energy?\n |publisher = Istituto di Geoscienze e Georisorse\n |place = Pisa, Italy\n |url = http://www.geothermal-energy.org/314,what_is_geothermal_energy.html\n |access-date = 2010-01-17\n |archive-url = https://web.archive.org/web/20110726100731/http://www.geothermal-energy.org/314,what_is_geothermal_energy.html\n |archive-date = 2011-07-26\n |url-status = dead\n}}</ref> Charlie Lieb developed the first [[downhole heat exchanger]] in 1930 to heat his house. Steam and hot water from geysers began heating homes in Iceland starting in 1943.\n\n[[File:geothermal capacity.svg|thumb|left|Global geothermal electric capacity. Upper red line is installed capacity;<ref name="Bertani">{{Citation\n| last =Bertani | first =Ruggero | date =September 2007\n| title =World Geothermal Generation in 2007\n| periodical =Geo-Heat Centre Quarterly Bulletin\n| location =Klamath Falls, Oregon\n| publisher =Oregon Institute of Technology\n| volume =28\n| issue =3\n| pages =8\u201319\n| url =http://geoheat.oit.edu/bulletin/bull28-3/art3.pdf\n| access-date =2009-04-12\n}}</ref> lower green line is realized production.<ref name="IPCC" />]]\n\nIn the 20th century, demand for electricity led to the consideration of geothermal power as a generating source. Prince [[Piero Ginori Conti]] tested the first geothermal power generator on 4 July 1904, at the same Larderello dry steam field where geothermal acid extraction began. It successfully lit four light bulbs.<ref>{{Citation\n |author1=Tiwari, G. N. |author2=Ghosal, M. K. |title=Renewable Energy Resources: Basic Principles and Applications\n |publisher=Alpha Science\n |year=2005\n |isbn=978-1-84265-125-4\n}}{{page needed|date=February 2014}}</ref> Later, in 1911, the world's first commercial geothermal power plant was built there. It was the world's only industrial producer of geothermal electricity until New Zealand built a plant in 1958. In 2012, it produced some 594 megawatts.<ref name=sci2013>{{Citation |doi=10.1126/science.1235640|pmid = 23704561|title = More Power from Below|journal = Science|volume = 340|issue = 6135|pages = 933\u20134|year = 2013|last1 = Moore|first1 = J. N.|last2 = Simmons|first2 = S. F.|s2cid = 206547980|bibcode = 2013Sci...340..933M}}</ref>\n\nIn 1960, [[Pacific Gas and Electric]] began operation of the first successful geothermal electric power plant in the United States at The Geysers in California.<ref name="100years" /> The original turbine lasted for more than 30 years and produced 11 [[Megawatt|MW]] net power.<ref>{{Citation\n |last1 = McLarty\n |first1 = Lynn\n |last2 = Reed\n |first2 = Marshall J.\n |title = The U.S. Geothermal Industry: Three Decades of Growth\n |journal = Energy Sources, Part A\n |volume = 14\n |issue = 4\n |pages = 443\u2013455\n |year = 1992\n |url = http://geotherm.inel.gov/publications/articles/mclarty/mclarty-reed.pdf\n |doi = 10.1080/00908319208908739\n |access-date = 2009-11-05\n |archive-url = http://arquivo.pt/wayback/20160516221028/http://geotherm.inel.gov/publications/articles/mclarty/mclarty%2Dreed.pdf\n |archive-date = 2016-05-16\n |url-status = dead\n}}</ref>\n\nThe [[binary cycle power plant]] was first demonstrated in 1967 in the [[USSR]] and later introduced to the US in 1981.<ref name="100years">\n{{Citation\n| last =Lund | first =J.\n| date =September 2004\n| title =100 Years of Geothermal Power Production\n| periodical =Geo-Heat Centre Quarterly Bulletin | location =Klamath Falls, Oregon | publisher =Oregon Institute of Technology\n| volume =25\n| issue =3\n| pages =11\u201319\n| url =http://geoheat.oit.edu/bulletin/bull25-3/art2.pdf\n| access-date =2009-04-13\n}}</ref> This technology allows the generation of electricity from much lower temperature resources than previously. In 2006, a binary cycle plant in [[Chena Hot Springs, Alaska]], came on-line, producing electricity from a record low fluid temperature of {{convert|57|C}}.<ref name="Chena">\n{{Citation\n | title = Understanding the Chena Hot flop\u00eb Springs, Alaska, geothermal system using temperature and pressure data\n | year = 2008\n | journal = Geothermics\n | pages = 565\u2013585\n | volume = 37\n | issue = 6\n | last1 = Erkan | first1 = K.\n | last2 = Holdmann | first2 = G.\n | last3 = Benoit | first3 = W.\n | last4 = Blackwell | first4 = D.\n | doi = 10.1016/j.geothermics.2008.09.001\n}}</ref>"}},
{"article_title": "Optical microscope", "pageid": "117534", "revid": "1063131242", "timestamp": "2022-01-01T11:38:13Z", "history_paths": [["Optical microscope --- Introduction ---", "History"]], "categories": ["microscopes", "dutch inventions", "science and technology in the dutch republic", "1590s in the dutch republic", "1600s in the dutch republic", "17th-century inventions", "optical microscopy"], "heading_tree": {"Optical microscope --- Introduction ---": {"Types": {"Simple microscope": {}, "Compound microscope": {}, "Other microscope variants": {}, "Digital microscope": {}}, "History": {"Invention": {}, "Popularization": {}, "Lighting techniques": {}, "Fluorescence microscopy": {}}, "Components": {"Eyepiece (ocular lens)": {}, "Objective turret (revolver or revolving nose piece)": {}, "Objective lens": {"Oil immersion objective": {}}, "Focus knobs": {}, "Frame": {}, "Stage": {}, "Light source": {}, "Condenser": {}}, "Magnification": {"Magnification and micrographs": {}}, "Operation": {"Illumination techniques": {}, "Other techniques": {}}, "Applications": {}, "Limitations": {"Surpassing the resolution limit": {"Structured illumination SMI": {}, "Localization microscopy SPDMphymod": {}, "3D super resolution microscopy": {}, "STED": {}}}, "Alternatives": {}, "See also": {}, "References": {}, "Cited sources": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Optical microscope --- Introduction ---|History": "{{See also|History of optics|Timeline of microscope technology}}\n\n The earliest microscopes were single [[lens (optics)|lens]] [[magnifying glass]]es with limited magnification which date at least as far back as the widespread use of lenses in [[eyeglasses]] in the 13th century.<ref>Atti Della Fondazione Giorgio Ronchi E Contributi Dell'Istituto Nazionale Di Ottica, Volume 30, La Fondazione-1975, page 554</ref>\n\nCompound microscopes first appeared in Europe around 1620<ref>{{cite book|author1=Albert Van Helden|author2=Sven Dupr\u00e9|author3=Rob van Gent|title=The Origins of the Telescope|url=https://books.google.com/books?id=XguxYlYd-9EC&pg=PA24|year=2010|publisher=Amsterdam University Press|isbn=978-90-6984-615-6|page=24}}</ref><ref>William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, pp. 391\u2013392</ref> including one demonstrated by [[Cornelis Drebbel]] in London (around 1621) and one exhibited in Rome in 1624.<ref name="Raymond J. Seeger 2016, page 24">Raymond J. Seeger, Men of Physics: Galileo Galilei, His Life and His Works, Elsevier - 2016, page 24</ref><ref name="J. William Rosenthal 1996, page 391">J. William Rosenthal, Spectacles and Other Vision Aids: A History and Guide to Collecting, Norman Publishing, 1996, page 391</ref>\n\nThe actual inventor of the compound microscope is unknown although many claims have been made over the years. These include a claim 35<ref>{{cite book|author1=Albert Van Helden|author2=Sven Dupr\u00e9|author3=Rob van Gent|title=The Origins of the Telescope|url=https://books.google.com/books?id=XguxYlYd-9EC&pg=PA36|year=2010|publisher=Amsterdam University Press|isbn=978-90-6984-615-6|pages=32\u201336, 43}}</ref> years after they appeared by [[Dutch people|Dutch]] spectacle-maker Johannes Zachariassen that his father, [[Zacharias Janssen]], invented the compound microscope and/or the telescope as early as 1590. Johannes' (some claim dubious)<ref>[[#Van Helden|Van Helden]], p. 43</ref><ref>Shmaefsky, Brian (2006) ''Biotechnology 101''. Greenwood. p. 171. {{ISBN|0313335281}}.</ref><ref>Note: stories vary, including Zacharias Janssen had the help of his father Hans Martens (or sometimes said to have been built entirely by his father). Zacharias' probable birth date of 1585 ([[#Van Helden|Van Helden]], p. 28) makes it unlikely he invented it in 1590 and the claim of invention is based on the testimony of Zacharias Janssen's son, Johannes Zachariassen, who may have fabricated the whole story ([[#Van Helden|Van Helden]], p. 43).</ref> testimony pushes the invention date so far back that Zacharias would have been a child at the time, leading to speculation that, for Johannes' claim to be true, the compound microscope would have to have been invented by Johannes' grandfather, Hans Martens.<ref>Brian Shmaefsky, Biotechnology 101 - 2006, page 171</ref> Another claim is that Janssen's competitor, [[Hans Lippershey]] (who applied for the first telescope patent in 1608) also invented the compound microscope.<ref>{{cite web|url=http://www.livescience.com/39649-who-invented-the-microscope.html|title=Who Invented the Microscope?|access-date=31 March 2017|url-status=live|archive-url=https://web.archive.org/web/20170203052525/http://www.livescience.com/39649-who-invented-the-microscope.html|archive-date=3 February 2017}}</ref> Other historians point to the Dutch innovator Cornelis Drebbel with his 1621 compound microscope.<ref name="Raymond J. Seeger 2016, page 24"/><ref name="J. William Rosenthal 1996, page 391"/>\n\n[[Galileo Galilei]] is also sometimes cited as a compound microscope inventor. After 1610, he found that he could close focus his telescope to view small objects, such as flies, close up<ref>Robert D. Huerta, Giants of Delft: Johannes Vermeer and the Natural Philosophers : the Parallel Search for Knowledge During the Age of Discovery, Bucknell University Press - 2003, page 126</ref> and/or could look through the wrong end in reverse to magnify small objects.<ref>A. Mark Smith, From Sight to Light: The Passage from Ancient to Modern Optics, University of Chicago Press - 2014, page 387</ref> The only drawback was that his 2 foot long telescope had to be extended out to 6 feet to view objects that close.<ref>Daniel J. Boorstin, The Discoverers, Knopf Doubleday Publishing Group - 2011, page 327</ref> After seeing the compound microscope built by  Drebbel exhibited in Rome in 1624, Galileo built his own improved version.<ref name="Raymond J. Seeger 2016, page 24"/><ref name="J. William Rosenthal 1996, page 391"/> In 1625, [[Giovanni Faber]] coined the name ''microscope'' for the compound microscope Galileo submitted to the [[Accademia dei Lincei]] in 1624 <ref>{{cite book |author=Gould, Stephen Jay |title=The Lying Stones of Marrakech: Penultimate Reflections in Natural History |url=https://archive.org/details/isbn_9780095031417 |url-access=registration | chapter = Chapter 2: The Sharp-Eyed Lynx, Outfoxed by Nature |publisher=Harmony |location=New York, N.Y |year=2000 |isbn=978-0-224-05044-9}}</ref> (Galileo had called it the "''occhiolino''" or "''little eye''"). Faber coined the name from the [[Greek language|Greek]] words ''\u03bc\u03b9\u03ba\u03c1\u03cc\u03bd'' (micron) meaning "small", and ''\u03c3\u03ba\u03bf\u03c0\u03b5\u1fd6\u03bd'' (skopein) meaning "to look at", a name meant to be analogous with "[[telescope]]", another word coined by the Linceans.<ref>[http://brunelleschi.imss.fi.it/esplora/microscopio/dswmedia/risorse/testi_completi.pdf "Il microscopio di Galileo"] {{webarchive|url=https://web.archive.org/web/20080409010159/http://brunelleschi.imss.fi.it/esplora/microscopio/dswmedia/risorse/testi_completi.pdf |date=9 April 2008 }}, Instituto e Museo di Storia della Scienza (in Italian)</ref>\n\n[[Christiaan Huygens]], another Dutchman, developed a simple 2-lens ocular system in the late 17th century that was [[Achromatic lens|achromatically]] corrected, and therefore a huge step forward in microscope development. The Huygens ocular is still being produced to this day, but suffers from a small field size, and other minor disadvantages.\n\n [[File:Stelluti bees1630.jpg|thumb|right|The oldest published image known to have been made with a microscope: bees by [[Francesco Stelluti]], 1630<ref>Gould, Stephen Jay (2000) ''[[The Lying Stones of Marrakech]]''. Harmony Books. {{ISBN|0-609-60142-3}}.</ref>]]\n[[Antonie van Leeuwenhoek]] (1632\u20131724) is credited with bringing the microscope to the attention of biologists, even though simple magnifying lenses were already being produced in the 16th century. Van Leeuwenhoek's home-made microscopes were simple microscopes, with a single very small, yet strong lens. They were awkward in use, but enabled van Leeuwenhoek to see detailed images. It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses. In the 1850s, [[John Leonard Riddell]], Professor of Chemistry at [[Tulane University]], invented the first practical binocular microscope while carrying out one of the earliest and most extensive American microscopic investigations of [[cholera]].<ref name="Riddell">{{cite journal | author = Riddell JL | title = On the binocular microscope | journal = Q J Microsc Sci | volume = 2 | pages = 18\u201324 | year = 1854}}</ref><ref name="Cassedy">{{cite journal | author = Cassedy JH | title = John L. Riddell's Vibrio biceps: Two documents on American microscopy and cholera etiology 1849\u201359 | journal = J Hist Med | volume = 28 | pages = 101\u2013108 | year = 1973 | issue=2}}</ref>\n\n While basic microscope technology and optics have been available for over 400 years it is much more recently that techniques in sample illumination were developed to generate the high quality images seen today.\n\nIn August 1893, [[August K\u00f6hler]] developed [[K\u00f6hler illumination]]. This method of sample illumination gives rise to extremely even lighting and overcomes many limitations of older techniques of sample illumination. Before development of K\u00f6hler illumination the image of the light source, for example a [[lightbulb]] filament, was always visible in the image of the sample.\n\nThe [[Nobel Prize]] in physics was awarded to Dutch physicist [[Frits Zernike]] in 1953 for his development of [[phase contrast]] illumination which allows imaging of transparent samples. By using [[Interference (wave propagation)|interference]] rather than [[Absorption (electromagnetic radiation)|absorption]] of light, extremely transparent samples, such as live [[mammalian]] cells, can be imaged without having to use staining techniques. Just two years later, in 1955, [[Georges Nomarski]] published the theory for [[differential interference contrast]] microscopy, another [[Interference (wave propagation)|interference]]-based imaging technique.\n\n Modern biological microscopy depends heavily on the development of [[fluorescent]] [[Hybridization probe|probe]]s for specific structures within a cell. In contrast to normal transilluminated light microscopy, in [[fluorescence microscopy]] the sample is illuminated through the objective lens with a narrow set of wavelengths of light. This light interacts with fluorophores in the sample which then emit light of a longer [[wavelength]]. It is this emitted light which makes up the image.\n\nSince the mid-20th century chemical fluorescent stains, such as [[DAPI]] which binds to [[DNA]], have been used to label specific structures within the cell. More recent developments include [[immunofluorescence]], which uses fluorescently labelled [[antibodies]] to recognise specific proteins within a sample, and fluorescent proteins like [[Green fluorescent protein|GFP]] which a live cell can [[gene expression|express]] making it fluorescent."}},
{"article_title": "Innovation", "pageid": "118450", "revid": "1061514647", "timestamp": "2021-12-22T04:20:42Z", "history_paths": [["Innovation --- Introduction ---", "History"]], "categories": ["innovation", "design", "innovators", "innovation economics", "product management", "science and technology studies"], "heading_tree": {"Innovation --- Introduction ---": {"Definition": {"Creativity and innovation": {}}, "Types": {"Sustaining vs disruptive innovation": {}, "Four types model": {}, "Non-economic innovation": {}}, "History": {}, "Process of innovation": {"Sources of innovation": {}, "Facilitating innovation": {}, "Goals and failures": {}}, "Diffusion": {}, "Measures": {"Organizational-level": {}, "Political-level": {}, "Indicators": {}, "Indices": {}, "Rankings": {}, "Rate of innovation": {}, "Innovation and development": {}}, "Government policies": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Innovation --- Introduction ---|History": "{{See also|Innovation economics}}\nThe word "innovation" once had a quite different meaning. The first full-length discussion about innovation is the account by the Greek philosopher and historian [[Xenophon]] (430\u2013355 BCE). He viewed the concept as multifaceted and connected it to political action. The word for innovation that he uses is 'Kainotomia' and before him it had been used in two plays by [[Aristophanes]]. [[Plato]] discussed innovation in his book Laws and was not very fond of the concept. He was skeptical to it in both culture (dancing and art) and education (he did not believe in introducing new games and toys to the kids).<ref name=":0">{{Cite book|last=Godin, Benoit|url=https://www.worldcat.org/oclc/903958473|title=Innovation contested : the idea of innovation over the centuries|year=2015|isbn=978-1-315-85560-8|location=New York, New York|oclc=903958473}}</ref> [[Aristotle]] did not like organizational innovations as he believed that all possible forms of organization had been discovered. (Politics II as cited by [[Beno\u00eet Godin]] 2015)\n\nBefore the 4th century in Rome, the words ''novitas'' and ''res nova / nova resmeant'' were used with either negative or positive judgment on the innovator. This concept meant renewing and was incorporated into the new word ''innovo'' in the centuries that followed. It was used in the ''[[Vulgate]]'' Bible in spiritual as well as political contexts. It was also used in poetry and then mainly had spiritual connotations but was also connected to political, material and cultural aspects.<ref name=":0" />\n\nIn [[Niccol\u00f2 Machiavelli|Machiavelli]]'s [[The Prince]] (1513), innovation is described in a political setting. It is portrayed as a strategy a Prince may employ in order to cope with a constantly changing world as well as the corruption within it. Here innovation is described as introducing change in government (new laws and institutions) in Machiavelli's later book The Discourses (1528) innovation is described as imitation, as a return to the original that has been corrupted by people and by time. Thus for Machiavelli Innovation came with positive connotations. This is however an exception in the description of innovation from the 16th century and onward. No innovator from the renaissance until the late 19th century ever thought of applying the word innovator upon themselves, it was a word used to attack enemies.<ref name=":0" />\n\nFrom the 1400s{{citation needed|date=September 2020}} through the 1600s,  the concept of innovation was pejorative \u2013 the term was an [[Early Modern English|early-modern]] synonym for "rebellion", "revolt" and "heresy".<ref name="Mazzaferro">{{cite journal|last1=Mazzaferro|first1=Alexander|year=2018|title=Such a Murmur": Innovation, Rebellion, and Sovereignty in William Strachey's "True Reportory|journal=Early American Literature|volume=53|issue=1|pages=3\u201332|doi=10.1353/eal.2018.0001|s2cid=166005186}}</ref><ref name="Diss">{{cite thesis|last1=Mazzaferro|first1=Alexander McLean|url=https://rucore.libraries.rutgers.edu/rutgers-lib/55583/|title="No newe enterprize" (Doctoral dissertation)|date=2017|publisher=Rutgers University|location=Camden, New Jersey|doi=10.7282/T38W3HFQ|access-date=19 February 2019}}</ref><ref name="Lepore">{{cite news|last1=Lepore|first1=Jill|date=23 June 2014|title=The Disruption Machine: What the gospel of innovation gets wrong|work=The New Yorker|url=https://www.newyorker.com/magazine/2014/06/23/the-disruption-machine|access-date=19 February 2019|quote=The word 'innovate'\u2014to make new\u2014used to have chiefly negative connotations: it signified excessive novelty, without purpose or end. [[Edmund Burke]] called the French Revolution a 'revolt of innovation'; [[Federalists]] declared themselves to be 'enemies to innovation.' [[George Washington]], on his deathbed, was said to have uttered these words: 'Beware of innovation in politics.' Noah Webster warned in his dictionary, in 1828, 'It is often dangerous to innovate on the customs of a nation.'}}</ref><ref name="Green">{{cite news|last1=Green|first1=Emma|date=20 June 2013|title=Innovation: The History of a Buzzword|work=The Atlantic|url=https://www.theatlantic.com/business/archive/2013/06/innovation-the-history-of-a-buzzword/277067/|access-date=19 February 2019}}\n</ref><ref>{{oed|innovation}}\n</ref> In the 1800s people promoting [[capitalism]] saw [[socialism]] as an innovation and spent a lot of energy working against it. For instance [[Goldwin Smith]] saw the spread of social innovations as an attack on money and banks. These social innovations were socialism, communism, nationalization, cooperative associations.<ref name=":0" />\n\nIn the 1900s the concept of innovation did not become popular until after the Second World War. This is the point in time when people started to talk about ''technological'' product innovation and tie it to the idea of economic growth and competitive advantage.<ref>{{Cite book|last=Godin, Benoit|url=https://www.worldcat.org/oclc/1125747489|title=The invention of technological innovation : languages, discourses and ideology in historical perspective|others=Edward Elgar Publishing|year=2019|isbn=978-1-78990-334-8|location=Cheltenham, UK|oclc=1125747489}}</ref> [[Joseph Schumpeter]] (1883\u20131950) is often credited for being the one who made the term popular and he contributed greatly to the study of [[innovation economics]],\n\nIn [[commerce|business]] and in [[economics]], innovation can be a catalyst for growth. With rapid advancements in [[transportation]] and [[communications]] over the past few decades, the old concepts of [[factor endowment]]s and [[comparative advantage]] which focused on an area's unique inputs are outmoded in today's [[globalization|global economy]]. Schumpeter argued that industries must incessantly revolutionize the economic structure from within, that is innovate with better or more effective processes and products, as well as market distribution, such as the connection from the craft shop to factory. He famously asserted that "[[creative destruction]] is the essential fact about [[capitalism]]".<ref name="capsocdem">{{cite book | author = Schumpeter, J. A. | author-link = Joseph Schumpeter | year = 1943 | title = Capitalism, Socialism, and Democracy | publisher = Routledge | edition = 6 | pages = 81\u201384 | isbn = 978-0-415-10762-4}}</ref> [[Entrepreneur]]s continuously look for better ways to satisfy their [[consumer demand|consumer base]] with improved quality, durability, service and price which come to fruition in innovation with advanced technologies and organizational strategies.<ref>Heyne, P., Boettke, P. J., and Prychitko, D. L. (2010). ''The Economic Way of Thinking''. Prentice Hall, 12th ed. pp. 163, 317\u201318.</ref>\n\nA prime example of innovation involved the boom of [[Silicon Valley]] startups out of the [[Stanford Industrial Park]]. In 1957, dissatisfied employees of [[Shockley Semiconductor]], the company of [[Nobel laureate]] and co-inventor of the [[transistor]] [[William Shockley]], left to form an independent firm, [[Fairchild Semiconductor]]. After several years, Fairchild developed into a formidable presence in the sector. Eventually, these founders left to start their own companies based on their own unique ideas, and then leading employees started their own firms. Over the next 20 years, this process resulted in the momentous [[startup company|startup-company]] explosion of [[information technology|information-technology]] firms. Silicon Valley began as 65 new enterprises born out of Shockley's eight former employees.<ref>{{cite web|url= http://www.netvalley.com/svhistory.html |title= Silicon Valley History & Future |website= Netvalley.com |access-date= 14 March 2016}}</ref>\n\nAnother example involves [[business incubator]]s \u2013 a phenomenon nurtured by governments around the world, close to knowledge clusters (mostly research-based) like universities or other Government Excellence Centres \u2013 which aim primarily to channel generated knowledge to applied innovation outcomes in order to stimulate regional or national [[economic growth]].<ref>\n{{Cite journal\n|last1= Rubin|first1= Tzameret H.|last2= Aas|first2= Tor Helge\n|last3= Stead|first3= Andrew|date= 1 July 2015\n|title= Knowledge flow in Technological Business Incubators: Evidence from Australia and Israel\n|journal= Technovation|volume= 41\u201342|pages= 11\u201324\n|doi= 10.1016/j.technovation.2015.03.002\n}}\n</ref>"}},
{"article_title": "Phonograph cylinder", "pageid": "125659", "revid": "1059502286", "timestamp": "2021-12-09T20:51:42Z", "history_paths": [["Phonograph cylinder --- Introduction ---"], ["Phonograph cylinder --- Introduction ---", "Early development"], ["Phonograph cylinder --- Introduction ---", "Commercial packaging"], ["Phonograph cylinder --- Introduction ---", "Hard plastic cylinders"], ["Phonograph cylinder --- Introduction ---", "Disc records"], ["Phonograph cylinder --- Introduction ---", "Decline"], ["Phonograph cylinder --- Introduction ---", "Later applications"]], "categories": ["audio storage", "audiovisual introductions in 1877", "audiovisual introductions in 1888", "thomas edison", "alexander graham bell", "american inventions", "obsolete technologies"], "heading_tree": {"Phonograph cylinder --- Introduction ---": {"Early development": {}, "Commercial packaging": {}, "Hard plastic cylinders": {}, "Disc records": {}, "Advantages of cylinders": {}, "Advantages of discs": {}, "Decline": {}, "Later applications": {}, "Preservation of cylinder recordings": {}, "Gallery": {}, "Demonstration": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Phonograph cylinder --- Introduction ---": "{{short description|Medium for recording and reproducing sound}}\n{{multiple issues|\n{{more citations needed|date=January 2017}}\n{{original research|date=January 2017}}\n}}\n[[File:EdisonPhonograph.jpg|thumb|Edison wax cylinder phonograph c. 1899]]\n'''Phonograph cylinders''' are the earliest commercial medium for [[Sound recording and reproduction|recording and reproducing sound]]. Commonly known simply as "records" in their era of greatest popularity (c. 1896\u20131915), these hollow [[cylinder|cylindrical]] objects have an audio recording engraved on the outside surface, which can be reproduced when they are played on a mechanical cylinder [[phonograph]].<ref name="prezi">{{Cite web\n| url = https://prezi.com/6vthtpprlye5/history-of-recorded-music/\n| title = History of Recorded Music\n| access-date = 2018-01-12\n| author = Aodhan Phipps\n| date = November 8, 2013\n| work = Transcript of History of Recorded Music\n| publisher = Prezi\n}}</ref> In the 1910s, the competing [[phonograph record|disc record]]<!-- BE usage resulting from corporate history and legal proceedings notwithstanding, "phonograph" is the Edison-created overarching generic term for ALL systems in which sound is physically recorded as modulations of a groove \u2014 e.g., Edison's own naming of his "Diamond Disc Phonograph", inclusion of disc format options in early Edison patents, etc. --> system [[Format war|triumphed]] in the marketplace to become the dominant commercial audio medium.<ref name="PBS">\n{{Cite web\n| url = https://www.pbs.org/wgbh/pages/frontline/shows/music/inside/cron.html\n| title = Chronology: Technology and the Music Industry\n| access-date = 2018-01-12\n| author = Callie Taintor\n| date = May 27, 2004\n| work = [[Frontline (American TV program)|Frontline]]\n| publisher = [[PBS]]\n}}</ref>\n\n [[File:CylinderRecordsWPackage.jpg|thumb|Two Edison cylinder records (left and right) and their cylindrical cardboard boxes (center)]]\n[[File:Brownwaxcylinders.jpg|thumb|Brown wax cylinders showing various shades (and mold damage)]]\nIn December 1877,<ref name="congress" /> [[Thomas Edison]] and his team invented the [[phonograph]] using a thin sheet of [[tin foil]] wrapped around a hand-cranked grooved metal cylinder.<ref>{{cite web|url=http://www.mixonline.com/news/news-products/1877-thomas-edison-cylinder-recorder/383579|title=1877 Thomas Edison Cylinder Recorder|date=September 1, 2006|work=[[Mix (magazine)|Mix Magazine]]|access-date=2016-07-11}}</ref> Tin foil was not a practical recording medium for either commercial or artistic purposes and the crude hand-cranked phonograph was only marketed as a novelty, to little or no profit. Edison moved on to developing a practical [[Edison light bulb|incandescent electric light]] and the next improvements to [[History of sound recording|sound recording technology]] were made by others.<ref name="PBS" />\n\nFollowing seven years of research and experimentation at their [[Volta Laboratory and Bureau#Sound recording and phonograph development|Volta Laboratory]], [[Charles Sumner Tainter]], [[Alexander Graham Bell]], and [[Chichester Bell]] introduced [[wax]] as the recording medium and engraving, rather than indenting, as the recording method. In 1887, their "[[Graphophone]]" system was being put to the test of practical use by official reporters of the [[United States Congress|US Congress]], with commercial units later being produced by the [[Dictaphone|Dictaphone Corporation]].<ref name="acusd">{{Cite web|url=http://history.acusd.edu/gen/recording/notes.html|archive-url=https://web.archive.org/web/20060813081151/http://history.acusd.edu/gen/recording/notes.html|url-status=dead|archive-date=August 13, 2006|title=Recording Technology History|access-date=2018-01-12|first=Steve|last=Schoenherr|date=July 6, 2005|publisher=University of San Diego}}</ref> After this system was demonstrated to Edison's representatives, Edison quickly resumed work on the phonograph. He settled on a thicker all-wax cylinder, the surface of which could be repeatedly shaved down for reuse. Both the Graphophone and Edison's "[[Edison phonograph|Perfected Phonograph]]" were commercialized in 1888. Eventually, a patent-sharing agreement was signed and the wax-coated cardboard tubes were abandoned in favor of Edison's all-wax cylinders as an interchangeable standard format.<ref>Schoenherr, S. (1999) [http://www.aes.org/aeshc/docs/recording.technology.history/graphophone.html "Charles Sumner Tainter and the Graphophone"] (via the Audio Engineering Society). Retrieved 2014-05-04.</ref>\n\n{{stack|{{Listen|type=music|filename=Edison cylinder Lost Chord.ogg|title=One of the earliest surviving recordings of music|description=1888 recording of Arthur Sullivan's "[[The Lost Chord]]", recorded by [[George Gouraud]], and played at the August 14, 1888, press conference that introduced the phonograph to London.}}}}\nBeginning in 1889, prerecorded wax cylinders were marketed. These have professionally made recordings of songs, instrumental music or humorous monologues in their grooves. At first, the only customers for them were proprietors of nickel-in-the-slot machines\u2014the first [[jukebox]]es\u2014installed in arcades and taverns, but within a few years, private owners of phonographs were increasingly buying them for home use. Each cylinder can easily be placed on and removed from the [[mandrel]] of the machine used to play them.<ref name="Reiss">{{Cite book|url=https://books.google.com/books?id=hVTcbLuuA5IC&q=Each+cylinder+can+easily+be+placed+on+and+removed+from+the+mandrel+of+the+machine+used+to+play+them&pg=PA1|title=Mechanics|access-date=2018-01-12|first=Eric L.|last=Reiss|date=1954|work=The Compleat Talking Machine: A Collector's Guide to Antique Phonographs|publisher=Sanoran Publishing|isbn=9781886606227}}</ref> Unlike later, shorter-playing high-speed cylinders, early cylinder recordings were usually cut at a speed of about 120 rpm and can play for as long as three minutes.<ref name="congress">{{Cite web|url=https://www.loc.gov/collections/edison-company-motion-pictures-and-sound-recordings/articles-and-essays/history-of-edison-sound-recordings/history-of-the-cylinder-phonograph/|title=History of the Cylinder Phonograph|access-date=2018-01-12|work=Inventing Entertainment: The Early Motion Pictures and Sound Recordings of the Edison Companies|publisher=Library of Congress}}</ref> They were made of a relatively soft wax formulation and would wear out after they were played a few dozen times.<ref name="Adapters">{{Cite web|url=http://45recordadapters.com/10-record-types/|title=13 All About the Records|access-date=2018-01-12|first=Russ|last=Orcutt|date=September 7, 2017|work=45 Record Adapters|publisher=45 Record Adapters}}</ref> The buyer could then<!--reference needed: either bring the worn cylinders back to the dealer to be traded in as partial credit for purchase of new recordings, or have--> use a mechanism which left their surfaces shaved smooth so new recordings could be made on them.<ref name="Gracyk">{{Cite web|url=http://www.gracyk.com/cylinders.shtml|title=Phonograph Cylinders: A Beginner's Guide|access-date=2018-01-12|first=Tim|last=Gracyk|date=2006|publisher=Tim's Phonographs and Old Records}}</ref>\n\n[[File:EdisonSlip1903.JPG|thumb|upright|Paper record slip from 1903 cylinder]]\n[[File:EdisonSlip1903backside.JPG|thumb|Back side of 1903 record slip]]\nCylinder machines of the late 1880s and the 1890s were usually sold with recording attachments. The ability to record as well as play back sound was an advantage of cylinder phonographs over the competition from cheaper [[phonograph record|disc record]] phonographs which began to be mass-marketed at the end of the 1890s, as the disc system machines could be used only to play back prerecorded sound.<ref name="Gracyk" />\n\nIn the earliest stages of phonograph manufacturing, various competing incompatible types of cylinder recordings were made. A standard system was decided upon by [[Edison Records]], [[Columbia Phonograph]], and other companies in the late 1880s. The standard cylinders are about {{convert|4|in|cm}} long, {{convert|2+1/4|in|cm}} in diameter, and play about two minutes of music or other sound.<ref name="Adapters" />\n\nOver the years, the type of wax used in cylinders was improved and hardened so that cylinders could be played with good quality over 100 times. In 1902, Edison Records launched a line of improved, hard wax cylinders marketed as "Edison Gold Moulded Records". The major development of this line of cylinders is that Edison had developed a process that allowed a mold to be made from a master cylinder which then permitted the production of several hundred cylinders to be made from the mold.<ref>{{cite web|url=http://www.cylinder.de/guide_black-wax-cylinders.html|title=The Cylinder Archive \u2013 Cylinder Guide: Black Wax Cylinders}}</ref> The process was labeled "Gold Moulded" because of the [[gold]] [[vapor]] that was given off by gold [[Electrode|electrodes]] used in the process.<ref name="congress" />\n\nOriginally, all cylinders sold had to be recorded live on the softer brown wax which wore out after as few as 20 plays. Later cylinders were reproduced either mechanically or by linking phonographs together with rubber tubes.<ref>{{cite web|url=http://www.cylinder.de/guide_brown-wax-cylinders.html|title=Brown Wax Cylinders}}</ref> Although not completely satisfactory, the result was good enough to be sold.{{citation needed|date=October 2017}}\n\n {{stack|{{Listen|type=music|help=no|filename=Ujangong.ogg|title=Song of the "Ujangong" mask dance|description=Phonograph cylinder recorded in [[German New Guinea]] on August 23, 1904, by German [[anthropology|anthropologist]] [[Rudolf P\u00f6ch]]}}}}\n[[File:ColumbiaCylLabelPortion.jpg|thumb|Portion of the label from the outside of a Columbia cylinder box, before 1901. Note that the title is handwritten.]]\n[[File:Edisongoldmoulded.jpg|thumbnail|Edison Gold Moulded record made of relatively hard black wax, c. 1904]]\nCylinders were sold in cardboard tubes with cardboard caps on each end, the upper one a removable lid. Like cylindrical containers for hats, they were simply called "boxes", the word still used by experienced collectors.{{citation needed|date=November 2019}} Within them, the earliest soft wax cylinders came swathed in a separate length of thick cotton batting. Later, molded hard-wax cylinders were sold in boxes with a cotton lining. [[Celluloid]] cylinders were sold in unlined boxes. These protective boxes were normally kept and used to house the cylinders after purchase. Their general appearance allowed bandleader [[John Philip Sousa]] to deride their contents as "canned music", an epithet he borrowed from [[Mark Twain]],<ref>Bierley, Paul Edmund, "The Incredible Band of John Philip Sousa". [[University of Illinois Press]], 2006. p. 82.</ref> but that did not stop Sousa's band from profiting by recording on cylinders.\n\nThe earliest cylinder boxes have a plain brown paper exterior, sometimes rubber-stamped with the company name. By the late 1890s, record companies usually pasted a generic printed label around the outside of the box, sometimes with a penciled catalog number but no other indication of the identity of the recording inside. A slip of paper stating the title and performer was placed inside the box with the cylinder. At first, this information was handwritten or typed on each slip, but printed versions became more common once cylinders were sold in large enough quantities to justify the printing setup cost. The recording itself usually began with a spoken announcement of the title and performer and also the name of the record company. On a typical Edison record slip from 1903, the consumer is invited to cut off a coupon with the printed information and paste it onto the lid of the box. Alternatively, a circular area within the coupon could be cut out and pasted onto the end of a spindle for that cylinder in one of the specially built cases and cabinets made for storing cylinder records. Only a minority of cylinder record customers purchased such storage units, however. Slightly later, the record number was stamped on the lid, then later still, a printed label with the title and artist information was factory-applied to the lid. Shortly after the start of the 20th century, an abbreviated version of this information was impressed into or printed on one edge of the cylinder itself.\n\n {{See also|Blue Amberol Records|Edison Records}}\n{{stack|{{Listen|type=music|help=no|filename=Auld Lang Syne.ogg|title=1910 Indestructible Record|description="[[Auld Lang Syne]]", sung by [[Frank C. Stanley]]}}}}\n[[File:BlueAmberolRim.jpg|thumb|Rim of Edison "[[Blue Amberol Records|Blue Amberol]]" celluloid cylinder with plaster core]]\n[[File:AmberolLid.jpg|thumb|[[Blue Amberol Records|Blue Amberol]] cylinder box lid]]\nOn March 20, 1900, Thomas B. Lambert was granted a US patent (645,920) that described a process for mass-producing cylinders made from [[celluloid]], an early hard plastic. ({{ill|Henri Jules Lioret|fr}} of France was producing celluloid cylinders as early as 1893, but they were individually recorded rather than molded.) That same year, the Lambert Company of Chicago began selling cylinder records made of the material. They would not break if dropped and could be played thousands of times without wearing out, although the choice of the bright pink color of early cylinders was arguably a marketing error. The color was changed to black in 1903, but brown and blue cylinders were also produced. The coloring was purportedly because the dye reduced [[surface noise]]. Unlike wax, the hard, inflexible material could not be shaved and recorded over, but it had the advantage of being nearly permanent.<ref>{{cite web|url=http://www.cylinder.de/guide_lambert-cylinders.html|title=Norman Bruderhofer's Cylinder Guide \u2013 Lambert Cylinders|website=cylinder.de}}</ref><ref>{{cite web|url=http://www.phonographcylinders.com/lambert-replica-cylinder.php|title=Lambert Replica Cylinders|website=phonographcylinders.com|access-date=2012-03-15|url-status=dead|archive-url=https://web.archive.org/web/20120324014701/http://www.phonographcylinders.com/lambert-replica-cylinder.php|archive-date=2012-03-24}}</ref>\n\nSuch "indestructible" style cylinders are one of the most durable forms of sound recording produced in the entire era of analog audio media; they can withstand a greater number of playbacks before wearing out than later media such as the [[vinyl record]] or [[Compact Cassette|audio tape]]. Their only serious shortcoming is that the celluloid slowly shrinks over the years, so that if it is on a core of plaster, metal or other very unyielding material, the ever-increasing tension can ultimately cause the celluloid to split lengthwise. A typical Lambert cylinder will have shrunk by approximately 3 mm in length in the 100 years or so since its manufacture. (The actual amount is very dependent on storage conditions.) Thus the grooves will no longer be 100 per inch, and the cylinder will skip if played on a typical feed-screw-type machine. The diameter will also have shrunk and many such cylinders will no longer fit on the [[mandrel]] unless very carefully reamed to fit. Such cylinders can still be played quite satisfactorily on suitable modern equipment. The Lambert company was put out of business in 1906 due to repeated actions from Edison for patent infringement, which Lambert had not actually committed. It was the cost of defending the actions that eventually sank Lambert.{{Citation needed|date=May 2015}}\n\nThis superior technology was licensed by the Indestructible Record Company<ref>{{Cite web|date=2005-11-16|title=Cylinder Preservation and Digitalization Project|url=http://cylinders.library.ucsb.edu/history-indestructible.php|url-status=live|access-date=June 19, 2021|website=Indestructible Records {{!}} UCSB Cylinder Audio Archive|publisher=[[University of California, Santa Barbara Library]]}}</ref> in 1906 and [[Columbia Records|Columbia Phonograph Company]] in 1908. The [[Edison Bell]] company in Europe had separately licensed the technology and were able to market Edison's titles in both wax (popular series) and celluloid (indestructible series).{{sfn|Read|Welch|1976|page=146}} Lambert was able to license the process because the patent was not owned by the now defunct Lambert Company, but by Lambert himself.{{citation needed|date=December 2016}}\n\nIn late 1908, Edison had introduced wax cylinders that played for nominally 4 minutes (instead of the usual 2) under the ''Amberol'' brand. They were made from a harder (and more fragile) form of wax to withstand the smaller stylus used to play them. The longer playing time was achieved by shrinking the groove size and spacing them twice as close together. In 1912, the Edison company eventually acquired Lambert's patents to the celluloid technology, and almost immediately started production under a variation of their existing ''Amberol'' brand as ''Edison Blue Amberol Records''.<ref>{{cite web|url=http://www.cylinder.de/guide_blue-amberol-cylinders.html|title=The Cylinder Archive \u2013 Cylinder Guide: Amberol and 4-minute Indestructible Cylinders}}</ref> These new celluloid recordings were given a core made from [[plaster of Paris]]. The celluloid material itself was blue, but purple was introduced in 1919, "... for more sophisticated selections". The use of camphor in Edison's celluloid base rendered it more stable, and the plaster core provided further resistance to possible shrinkage, but the playing surface is still liable to split if stored in less than ideal conditions; however, the groove pitch rarely changes. The plaster core itself can deteriorate in conditions that are too damp or too dry. Nevertheless, most Blue Amberol cylinders are, today, quite playable on antique phonographs or modern equipment alike (although the plaster core may need some reaming).{{citation needed|date=December 2016}}\n\nEdison made several designs of phonographs both with internal and external horns for playing these improved cylinder records. The internal horn models were called ''Amberolas''. Edison marketed its "Fireside" model phonograph with a gearshift and a 'model K' reproducer with two styli that allowed it to play both 2-minute and 4-minute cylinders.<ref>Model Number taken directly from actual Fireside reproducer.</ref> Conversion kits were produced for some of the later model 2-minute phonographs adding a gear change and a second 'model H' reproducer. These kits were shipped with a set of 12 (wax) Amberol cylinders in distinctive orange boxes. The purchaser had no choice as to the titles.{{citation needed|date=December 2016}}\n\n In the era before [[World War I]], phonograph cylinders and [[gramophone record|disc records]] competed with each other for public favor.\n\nThe audio fidelity of a sound groove is improved{{Clarify|date=August 2019}} if it is engraved on a cylinder due to better linear tracking.{{Explain|date=August 2019}} This was not resolved{{dubious|date=August 2019}} until the advent of [[RIAA equalization|RIAA Equalization]] in the early 1940s\u2014by which time it had already been rendered academic, as cylinder production stopped with Edison's last efforts in October 1929.\n\n The cylinder system had certain advantages. As noted, wax cylinders could be used for home recordings, and "indestructible" types could be played over and over many more times than discs. Cylinders usually rotated twice as fast as contemporary discs, but the linear velocity was comparable to the innermost grooves of the disc. In theory,{{clarify|date=August 2019}} there would be generally{{clarify|date=August 2019}} poorer [[High fidelity|audio fidelity]]. Furthermore, since [[constant angular velocity]] translates into [[constant linear velocity]] (the radius of the [[helix|helical]] track is constant), cylinders were also free from inner-groove problems suffered by disc recordings. Around 1900, cylinders were, on average, indeed of notably higher audio quality than contemporary discs, but as disc makers improved their technology by 1910 the fidelity differences between better discs and cylinders became minimal.{{citation needed|date=August 2019}}{{dubious|date=August 2019}}\n\nCylinder phonographs generally used a [[worm drive|worm gear]] to move the stylus in synchronization with the grooves of the recording, whereas most disc machines relied on the grooves to pull the stylus along. This resulted in cylinder records played a number of times having less degradation than discs, but this added mechanism made cylinder machines more expensive.\n\n Both the disc records, and the machines to play them, were cheaper to mass-produce than the products of the cylinder system. Disc records were also easier and cheaper to store in bulk, as they could be stacked, or when in paper sleeves put in rows on shelves like books\u2014packed together more densely than cylinder recordings.\n\nMany cylinder phonographs used a belt to turn the mandrel; slight slippage of this belt could make the mandrel turn unevenly, thus resulting in pitch fluctuations. Disc phonographs using a direct system of gears turned more evenly; the heavy metal turntable of disc machines acted as a flywheel, helping to minimize speed wobble.\n\nVirtually all US disc records were single-sided until 1908, when [[Columbia Records]] began mass production of discs with recordings [[A-side and B-side|pressed on both sides]]. Except for premium-priced classical records, that quickly became the industry standard. With their capacity effectively doubled, the storage efficiency advantage of discs over the cylinder format became even more obvious.\n\nThe disc companies had superior advertising and promotion, most notably the [[Victor Talking Machine Company]] in the United States and the [[Gramophone Company]]/[[HMV]] in the Commonwealth. Great singers like [[Enrico Caruso]] were hired to record exclusively, helping put the idea in the public mind that that company's product was superior. Edison tried to get into the disc market with [[Vertical cut recording|hill-and-dale]] discs, [[Edison Disc Record]]s.\n\n [[File:PhonographCylinders.JPG|thumb|Disc records and cylinders]]\nCylinder records continued to compete with the growing disc record market into the 1910s, when discs won the commercial battle. In 1912, [[Columbia Records]], which had been selling both discs and cylinders, dropped the cylinder format, while Edison introduced his unique{{clarify|date=August 2019}} [[Edison Disc Record|Diamond Disc]] format. Beginning in 1915, new Edison cylinder issues were simply dubs of Edison discs and therefore had lower audio quality than the disc originals.{{Explain|date=August 2019}} Although his cylinders continued to be sold in steadily dwindling and eventually minuscule quantities, Edison continued to support owners of cylinder phonographs by making new titles available in that format until the company ceased manufacturing all records and phonographs in November 1929.<!-- presumably still available into October, but no new titles added after mid-year. --><ref name="congress" />\n\n [[File:Wax cylinder in Dictaphone.jpg|thumb|Cylinder on Dictaphone dictation machine (c. 1922). The recording head moved left to right. The black lines are shiny gaps between tracks. Each cylinder could record 1,200 to 1,500 words. They could be reused 100 to 120 times by putting them in a machine that erased them by shaving off the surface.]]\n\nCylinder phonograph technology continued to be used for [[Dictaphone]] and Ediphone recordings for office use for decades.<ref name="Dictaphone">{{Cite web|url=http://www.soundrecordinghistory.net/history-of-sound-recording/history-of-dictaphone/|title=History of Dictaphone|access-date=2018-01-12|author=Tim Gracyk|date=2018|work=History of Sound Recording Devices|publisher=Sound Recording History}}</ref>\n\nIn 1947, Dictaphone replaced wax cylinders with their [[Dictabelt]] technology, which cut a mechanical groove into a plastic belt instead of into a wax cylinder. This was later replaced by [[magnetic tape]] recording. However, cylinders for older style dictating machines continued to be available for some years, and it was not unusual to encounter cylinder dictating machines into the 1950s.<ref name="Dictabelt">{{Cite web|url=http://www.obsoletemedia.org/dictabelt/|title=History of Dictaphone|access-date=2018-01-12|first=Jason|last=Curtis|work=Museum of Obsolete Media|date=30 April 2013|publisher=Museum of Obsolete Media}}</ref>\n\nIn the late 20th and early 21st century, new recordings have been made on cylinders for the [[novelty effect]] of using obsolete technology. Probably the most famous of these are by [[They Might Be Giants]], who in 1996 recorded "I Can Hear You" and three other songs, performed without electricity, on an 1898 Edison wax recording studio phonograph at the [[Edison National Historic Site]] in [[West Orange, New Jersey]]. This song was released on ''[[Factory Showroom]]'' in 1996 and re-released on the 2002 compilation ''[[Dial-A-Song: 20 Years of They Might Be Giants]]''. The other songs recorded were "James K. Polk", "Maybe I Know", and "The Edison Museum", the last a song about the site of the recording. These recordings were officially released online as MP3 files in 2001.<ref name="giants">{{Cite web|url=https://www.theymightbegiants.com/factory-showroom|title=Factory Showroom|access-date=2018-01-12|date=2017|work=The Official Website of Brooklyn's Ambassadors of Love|publisher=They Might Be Giants}}</ref>\n\nSmall numbers of cylinders have been manufactured in the 21st century out of modern long-lasting materials. Two companies engaged in such enterprise are the Vulcan Cylinder Record Company of [[Sheffield]], England,<ref>{{cite web|url=http://www.phonographcylinders.com|title=New Phonograph Cylinder Records|publisher=Vulcan Cylinder Record Company|date=2002|access-date=2014-10-20}}</ref> and the Wizard Cylinder Records Company in [[Baldwin, Nassau County, New York|Baldwin, New York]].<ref>{{cite web|url=http://www.capsnews.org/apn2008-6.htm|title=The Wizard Cylinder Record Company|author=Peter N. Dilg|work=Canadian Antique Phonograph Society|date=November\u2013December 2008|access-date=2014-10-20}}</ref> Both appear to have started in 2002.\n\nIn 2010 the British [[steampunk]] band [[The Men That Will Not Be Blamed for Nothing]] released the track "Sewer", from their debut album, ''[[Now That's What I Call Steampunk! Volume 1]]'' on a wax cylinder in a limited edition of 40, of which only 30 were put on sale. The box set came with instructions on how to make your own cylinder player for less than \u00a320. The [[BBC]] covered the release on Television on [[BBC Click]], on [[BBC Online]], and on [[Radio 5 Live]].<ref>{{cite news| url=http://news.bbc.co.uk/1/hi/technology/10171206.stm | work=BBC News | title=Tech Know: A journey into sound | date=2010-05-27}}</ref>\n\nIn August 2010, [[Ash International]] and PARC released the first commercially available glow in the dark phonograph cylinder, a work by [[Michael Esposito (paranormal investigator)|Michael Esposito]] and [[Carl Michael von Hausswolff]], entitled ''The Ghosts of Effingham''. The cylinder was released in a limited edition of 150 copies, and was produced by Vulcan Records in Sheffield, England.{{citation needed|date=October 2017}}\n\nIn June 2017 the Cthulhu Breakfast Club podcast released a special limited wax cylinder edition of a show.<ref>{{Cite web|publisher=[[British Library]]|date=2017-05-25|title=Podcast on Wax Cylinder|url=https://twitter.com/BL_DramaSound/status/867737576056258561|url-status=live|archive-url=|archive-date=|access-date=|via=Twitter}}</ref>\n\nIn April 2019, the podcast ''[[Hello Internet]]'' released ten limited edition wax cylinder recordings.<ref>[http://www.hellointernet.fm/podcast/2019/4/24/hi-122-wax-cylinders "Wax cylinder episode"], ''[[Hello Internet]]'', April 2019</ref>\n\n {{More citations needed section|date=November 2019}}\n[[File:HoldPhonoCylinder.jpg|thumbnail|Proper way to hold a cylinder record: put fingers on the inside; do not touch the outer surface which has the recording.]]\nBecause of the nature of the recording medium, playback of many cylinders can cause degradation of the recording. The replay of cylinders diminishes their fidelity and degrades their recorded signals. Additionally, when exposed to humidity, mold can penetrate a cylinder's surface and cause the recording to have surface noise. Currently, the only professional machine manufactured for the playback of cylinder recordings is the [[Arch\u00e9ophone]] player, designed by Henri Chamoux. The Arch\u00e9ophone is used by the Edison National Historic Site, [[Bowling Green State University]] (Bowling Green, Ohio), The Department of Special Collections, Donald C Davidson Library at The [[University of California, Santa Barbara]], and many other libraries and archives.\n\nOther modern plug-in mounts, each incorporating the use of a Stanton 500AL MK II magnetic cartridge, have been manufactured from time to time. Information on each may be viewed on the Phonograph Makers Pages link. It is possible to use these on the Edison cylinder players.\n\nAlso of interest is the cylinder player built by BBC engineers working in "Engineering Operations \u2013 Radio" in 1987. It was equipped with a linear-tracking arm borrowed from a contemporary Revox turntable, and a variety of re-tipped Shure SC35 cartridges.\n\nIn an attempt to preserve the historic content of the recordings, cylinders can be read with a [[confocal microscope]] and converted to a [[digital recording|digital audio]] format. The resulting sound clip in most cases sounds better than stylus playback from the original cylinder. Having an electronic version of the original recordings enables archivists to open access to the recordings to a wider audience. This technique also has the potential to allow for reconstruction of damaged or broken cylinders.{{sfn|Fedeyev|Haber|Radding|Maul|2004}} This method, developed by physicist [[Carl Haber (physicist)|Carl Haber]], is known as [[IRENE (technology)|IRENE]].\n\nModern reproductions of cylinder and disc recordings usually give the impression that the introduction of discs was a quantum leap in audio fidelity, but this is on modern playback equipment; played on equipment from around 1900, the cylinders do not have noticeably more rumble and poorer bass reproduction than the discs. Another factor is that many cylinders are amateur recordings, while disc recording equipment was simply too expensive for anyone but professional engineers; many extremely poor{{lopsided|date=June 2020}} recordings were made on cylinder, while the vast majority of disc recordings were competently recorded. All cylinder recordings were acoustically recorded as were early disc recordings. From the mid-1920s onward, discs started to be recorded electrically which provided a much enhanced frequency range of recording.\n\nAlso important is the quality of the material: the earliest tinfoil recordings wore out fast. Once the tinfoil was removed from the cylinder it was nearly impossible to realign in playable condition.\n\n{{Listen|help=no|filename=IsraelInEgypt18880629.ogg|title=An example of a heavily degraded cylinder: Handel's ''Israel in Egypt'' (June 29, 1888)|description=This is the earliest surviving intentional recording of music, and was played at the conference introducing the phonograph to London.<ref>[http://www.nps.gov/edis/photosmultimedia/very-early-recorded-sound.htm Very Early Recordings], from the Edison National Historic Site, [U.S.] National Park Service.</ref>\n|filename2=Arthur Sullivan - wax cylinder recording.ogg|title2=1888 speech by Arthur Sullivan at the Little Menlo, London|description2=One of the earliest surviving wax cylinder recordings.}}\nIn addition to poor{{lopsided|date=June 2020}} states of preservation, the poor impression{{lopsided|date=June 2020}} modern listeners may get of wax cylinders is from their early date, which can compare unfavorably{{lopsided|date=June 2020}} to recordings made even a dozen years later. Other than a single playable example from 1878 (from an experimental phonograph-clock), the oldest playable preserved cylinders are from the year 1888. These include a severely degraded{{lopsided|date=June 2020}} recording of [[Johannes Brahms]], Handel's ''[[Israel in Egypt]]'' and a short speech by Sir [[Arthur Sullivan]] in fairly listenable condition. Somewhat later are the 1889 amateur recordings of [[Nina Grieg]]. The problem with the wax cylinders is that they readily support the growth of mildew which penetrates throughout the cylinder and, if serious enough, renders the recording unplayable. The earliest preserved rubber disc recordings are children's records, featuring animal noises and nursery rhymes. This means that the earliest disc recordings most music lovers will hear are shellac discs made after 1900, after more than ten years of development.\n\n <gallery>\nFile:Cylinderscolors.JPG|Celluloid phonograph cylinders displaying a variety of colors\nFile:Cylindersdiameter.JPG|Wax phonograph cylinders in a variety of diameters\nFile:Cylinderslength.JPG|Wax phonograph cylinders in a variety of lengths\nFile:Mapleson cylinders.jpg|A sound engineer holds one of the [[Mapleson Cylinders]] containing a fragment of a live performance recorded at the [[Metropolitan Opera]] in 1901.\nFile:Amberola close-up.jpg|Close-up of the mechanism of an Edison Amberola, manufactured c. 1915\nFile:Thomas Edison listening to wax cylinder, 1888.png|Thomas Edison in 1888 listening to a wax cylinder phonograph at the Edison laboratory, Orange, N.J.\nFile:CBS-Listening-Post-Cylinders-1941.jpg|Delivering Ediphone wax cylinder recordings of propaganda broadcasts for analysis at the CBS listening post (May 1941)\nFile:CBS-Listening-Post-Transcription-1941.jpg|Transcribing propaganda broadcasts from Europe recorded on Ediphone cylinders at the CBS listening post (May 1941)\n</gallery>\n\n [[File:Edison cylinder playback demo.webm|thumb|Playback demonstration]]\nAudio/video recordings of a recording and playback demonstration at the [[Thomas Edison National Historical Park]] in [[West Orange, New Jersey]]. The performers are Earl Karlsen on mandolin, Arnie Reisman on banjo, and Drew Uhlmann on fiddle, performing "Jerusalem Ridge", a bluegrass classic attributed to [[Bill Monroe]]; the operator is Jerry Fabris, Museum Curator.\n\n[[File:Edison cylinder recording demo.webm|thumb|left|upright 1.5|Recording demonstration]]\n{{clear|left}}\n\n * [[Arch\u00e9ophone]]\n* [[Audio format]]\n* [[Audio storage]]\n* [[Cylinder Audio Archive]]\n* [[Mapleson Cylinders]]\n* [[Telediphone]]\n* [[Volta Laboratory and Bureau]]\n\n '''Notes'''\n{{reflist}}\n\n'''Sources'''\n* {{cite journal|last1=Fedeyev|first1=Vitaliy|last2=Haber|first2=Carl|author2-link=Carl Haber (physicist)|last3=Radding|first3=Zachary|last4=Maul|first4=Christian|last5=McBride|first5=John|last6=Golden|first6=Mitchell|url=http://www-cdf.lbl.gov/~av/JAES-paper-LBNL.pdf|title=Reconstruction of Mechanically Recorded Sound by Image Processing|journal=[[Journal of the Acoustical Society of America]]|volume=115|issue=5|date=May 2004|page=172|bibcode=2001ASAJ..115.2494F|doi=10.1121/1.4782907}}\n* {{cite book|last1=Read|first1=Oliver|last2=Welch|first2=Walter L.|title=From Tin Foil to Stereo: Evolution of the Phonograph|edition=2nd|publisher=Howard W. Sams|location=Indianapolis, Indiana|year=1976|isbn=978-0672212062}}\n\n * {{cite book|last1=Frow|first1=George L.|last2=Sefl|first2=Albert F.|title=The Edison Cylinder Phonographs 1877\u20131929|publisher=George F. Frow|location=Sevenoaks, Kent|year=1978|isbn=0-9505462-2-4|ref=none}}\n* {{cite book|last=Koenigsberg|first=Allen|title=Edison Cylinder Records, 1889\u20131912, With an illustrated history of the phonograph|publisher=APM Press|location=Brooklyn, New York|year=1987|isbn=0-937612-07-3|ref=none}}\n* {{cite book|last=Morton Jr.|first=David L.|title=Sound Recording \u2013 The Life Story of a Technology|publisher=Johns Hopkins University Press|location=Baltimore, Maryland|year=2004|ref=none}}\n* {{cite book|last=Sch\u00fcller|first=Dietrich|chapter=Technology for the Future|title=Archives for the Future: Global Perspectives on Audiovisual Archives in the 21st Century|editor1=A. Seeger|editor2=S. Chaudhuri|publisher=Seagull Books|location=Calcutta, India|year=2004|ref=none}}\n\n {{Commons category|Phonograph cylinders}}\n* [http://www.tinfoil.com/ Tinfoil.com] \u2013 History of phonograph cylinders; listen to many examples dating from 1878 through 1912\n* [http://cylinders.library.ucsb.edu/ UCSB Cylinder Audio Archive], [[University of California, Santa Barbara]]: Streaming and downloadable versions of over 10,000 cylinders.\n* [https://www.vulcanrecords.com/ Vulcan Cylinder Record Company]\n* [http://sounds.bl.uk/World-and-traditional-music/Ethnographic-wax-cylinders Ethnographic wax cylinders] from the [[British Library]]]\n\n{{Audio formats}}\n{{Grooved track audio}}\n{{Alexander Graham Bell}}\n\n{{Authority control}}", "Phonograph cylinder --- Introduction ---|Early development": "[[File:CylinderRecordsWPackage.jpg|thumb|Two Edison cylinder records (left and right) and their cylindrical cardboard boxes (center)]]\n[[File:Brownwaxcylinders.jpg|thumb|Brown wax cylinders showing various shades (and mold damage)]]\nIn December 1877,<ref name="congress" /> [[Thomas Edison]] and his team invented the [[phonograph]] using a thin sheet of [[tin foil]] wrapped around a hand-cranked grooved metal cylinder.<ref>{{cite web|url=http://www.mixonline.com/news/news-products/1877-thomas-edison-cylinder-recorder/383579|title=1877 Thomas Edison Cylinder Recorder|date=September 1, 2006|work=[[Mix (magazine)|Mix Magazine]]|access-date=2016-07-11}}</ref> Tin foil was not a practical recording medium for either commercial or artistic purposes and the crude hand-cranked phonograph was only marketed as a novelty, to little or no profit. Edison moved on to developing a practical [[Edison light bulb|incandescent electric light]] and the next improvements to [[History of sound recording|sound recording technology]] were made by others.<ref name="PBS" />\n\nFollowing seven years of research and experimentation at their [[Volta Laboratory and Bureau#Sound recording and phonograph development|Volta Laboratory]], [[Charles Sumner Tainter]], [[Alexander Graham Bell]], and [[Chichester Bell]] introduced [[wax]] as the recording medium and engraving, rather than indenting, as the recording method. In 1887, their "[[Graphophone]]" system was being put to the test of practical use by official reporters of the [[United States Congress|US Congress]], with commercial units later being produced by the [[Dictaphone|Dictaphone Corporation]].<ref name="acusd">{{Cite web|url=http://history.acusd.edu/gen/recording/notes.html|archive-url=https://web.archive.org/web/20060813081151/http://history.acusd.edu/gen/recording/notes.html|url-status=dead|archive-date=August 13, 2006|title=Recording Technology History|access-date=2018-01-12|first=Steve|last=Schoenherr|date=July 6, 2005|publisher=University of San Diego}}</ref> After this system was demonstrated to Edison's representatives, Edison quickly resumed work on the phonograph. He settled on a thicker all-wax cylinder, the surface of which could be repeatedly shaved down for reuse. Both the Graphophone and Edison's "[[Edison phonograph|Perfected Phonograph]]" were commercialized in 1888. Eventually, a patent-sharing agreement was signed and the wax-coated cardboard tubes were abandoned in favor of Edison's all-wax cylinders as an interchangeable standard format.<ref>Schoenherr, S. (1999) [http://www.aes.org/aeshc/docs/recording.technology.history/graphophone.html "Charles Sumner Tainter and the Graphophone"] (via the Audio Engineering Society). Retrieved 2014-05-04.</ref>\n\n{{stack|{{Listen|type=music|filename=Edison cylinder Lost Chord.ogg|title=One of the earliest surviving recordings of music|description=1888 recording of Arthur Sullivan's "[[The Lost Chord]]", recorded by [[George Gouraud]], and played at the August 14, 1888, press conference that introduced the phonograph to London.}}}}\nBeginning in 1889, prerecorded wax cylinders were marketed. These have professionally made recordings of songs, instrumental music or humorous monologues in their grooves. At first, the only customers for them were proprietors of nickel-in-the-slot machines\u2014the first [[jukebox]]es\u2014installed in arcades and taverns, but within a few years, private owners of phonographs were increasingly buying them for home use. Each cylinder can easily be placed on and removed from the [[mandrel]] of the machine used to play them.<ref name="Reiss">{{Cite book|url=https://books.google.com/books?id=hVTcbLuuA5IC&q=Each+cylinder+can+easily+be+placed+on+and+removed+from+the+mandrel+of+the+machine+used+to+play+them&pg=PA1|title=Mechanics|access-date=2018-01-12|first=Eric L.|last=Reiss|date=1954|work=The Compleat Talking Machine: A Collector's Guide to Antique Phonographs|publisher=Sanoran Publishing|isbn=9781886606227}}</ref> Unlike later, shorter-playing high-speed cylinders, early cylinder recordings were usually cut at a speed of about 120 rpm and can play for as long as three minutes.<ref name="congress">{{Cite web|url=https://www.loc.gov/collections/edison-company-motion-pictures-and-sound-recordings/articles-and-essays/history-of-edison-sound-recordings/history-of-the-cylinder-phonograph/|title=History of the Cylinder Phonograph|access-date=2018-01-12|work=Inventing Entertainment: The Early Motion Pictures and Sound Recordings of the Edison Companies|publisher=Library of Congress}}</ref> They were made of a relatively soft wax formulation and would wear out after they were played a few dozen times.<ref name="Adapters">{{Cite web|url=http://45recordadapters.com/10-record-types/|title=13 All About the Records|access-date=2018-01-12|first=Russ|last=Orcutt|date=September 7, 2017|work=45 Record Adapters|publisher=45 Record Adapters}}</ref> The buyer could then<!--reference needed: either bring the worn cylinders back to the dealer to be traded in as partial credit for purchase of new recordings, or have--> use a mechanism which left their surfaces shaved smooth so new recordings could be made on them.<ref name="Gracyk">{{Cite web|url=http://www.gracyk.com/cylinders.shtml|title=Phonograph Cylinders: A Beginner's Guide|access-date=2018-01-12|first=Tim|last=Gracyk|date=2006|publisher=Tim's Phonographs and Old Records}}</ref>\n\n[[File:EdisonSlip1903.JPG|thumb|upright|Paper record slip from 1903 cylinder]]\n[[File:EdisonSlip1903backside.JPG|thumb|Back side of 1903 record slip]]\nCylinder machines of the late 1880s and the 1890s were usually sold with recording attachments. The ability to record as well as play back sound was an advantage of cylinder phonographs over the competition from cheaper [[phonograph record|disc record]] phonographs which began to be mass-marketed at the end of the 1890s, as the disc system machines could be used only to play back prerecorded sound.<ref name="Gracyk" />\n\nIn the earliest stages of phonograph manufacturing, various competing incompatible types of cylinder recordings were made. A standard system was decided upon by [[Edison Records]], [[Columbia Phonograph]], and other companies in the late 1880s. The standard cylinders are about {{convert|4|in|cm}} long, {{convert|2+1/4|in|cm}} in diameter, and play about two minutes of music or other sound.<ref name="Adapters" />\n\nOver the years, the type of wax used in cylinders was improved and hardened so that cylinders could be played with good quality over 100 times. In 1902, Edison Records launched a line of improved, hard wax cylinders marketed as "Edison Gold Moulded Records". The major development of this line of cylinders is that Edison had developed a process that allowed a mold to be made from a master cylinder which then permitted the production of several hundred cylinders to be made from the mold.<ref>{{cite web|url=http://www.cylinder.de/guide_black-wax-cylinders.html|title=The Cylinder Archive \u2013 Cylinder Guide: Black Wax Cylinders}}</ref> The process was labeled "Gold Moulded" because of the [[gold]] [[vapor]] that was given off by gold [[Electrode|electrodes]] used in the process.<ref name="congress" />\n\nOriginally, all cylinders sold had to be recorded live on the softer brown wax which wore out after as few as 20 plays. Later cylinders were reproduced either mechanically or by linking phonographs together with rubber tubes.<ref>{{cite web|url=http://www.cylinder.de/guide_brown-wax-cylinders.html|title=Brown Wax Cylinders}}</ref> Although not completely satisfactory, the result was good enough to be sold.{{citation needed|date=October 2017}}", "Phonograph cylinder --- Introduction ---|Commercial packaging": "{{stack|{{Listen|type=music|help=no|filename=Ujangong.ogg|title=Song of the "Ujangong" mask dance|description=Phonograph cylinder recorded in [[German New Guinea]] on August 23, 1904, by German [[anthropology|anthropologist]] [[Rudolf P\u00f6ch]]}}}}\n[[File:ColumbiaCylLabelPortion.jpg|thumb|Portion of the label from the outside of a Columbia cylinder box, before 1901. Note that the title is handwritten.]]\n[[File:Edisongoldmoulded.jpg|thumbnail|Edison Gold Moulded record made of relatively hard black wax, c. 1904]]\nCylinders were sold in cardboard tubes with cardboard caps on each end, the upper one a removable lid. Like cylindrical containers for hats, they were simply called "boxes", the word still used by experienced collectors.{{citation needed|date=November 2019}} Within them, the earliest soft wax cylinders came swathed in a separate length of thick cotton batting. Later, molded hard-wax cylinders were sold in boxes with a cotton lining. [[Celluloid]] cylinders were sold in unlined boxes. These protective boxes were normally kept and used to house the cylinders after purchase. Their general appearance allowed bandleader [[John Philip Sousa]] to deride their contents as "canned music", an epithet he borrowed from [[Mark Twain]],<ref>Bierley, Paul Edmund, "The Incredible Band of John Philip Sousa". [[University of Illinois Press]], 2006. p. 82.</ref> but that did not stop Sousa's band from profiting by recording on cylinders.\n\nThe earliest cylinder boxes have a plain brown paper exterior, sometimes rubber-stamped with the company name. By the late 1890s, record companies usually pasted a generic printed label around the outside of the box, sometimes with a penciled catalog number but no other indication of the identity of the recording inside. A slip of paper stating the title and performer was placed inside the box with the cylinder. At first, this information was handwritten or typed on each slip, but printed versions became more common once cylinders were sold in large enough quantities to justify the printing setup cost. The recording itself usually began with a spoken announcement of the title and performer and also the name of the record company. On a typical Edison record slip from 1903, the consumer is invited to cut off a coupon with the printed information and paste it onto the lid of the box. Alternatively, a circular area within the coupon could be cut out and pasted onto the end of a spindle for that cylinder in one of the specially built cases and cabinets made for storing cylinder records. Only a minority of cylinder record customers purchased such storage units, however. Slightly later, the record number was stamped on the lid, then later still, a printed label with the title and artist information was factory-applied to the lid. Shortly after the start of the 20th century, an abbreviated version of this information was impressed into or printed on one edge of the cylinder itself.", "Phonograph cylinder --- Introduction ---|Hard plastic cylinders": "{{See also|Blue Amberol Records|Edison Records}}\n{{stack|{{Listen|type=music|help=no|filename=Auld Lang Syne.ogg|title=1910 Indestructible Record|description="[[Auld Lang Syne]]", sung by [[Frank C. Stanley]]}}}}\n[[File:BlueAmberolRim.jpg|thumb|Rim of Edison "[[Blue Amberol Records|Blue Amberol]]" celluloid cylinder with plaster core]]\n[[File:AmberolLid.jpg|thumb|[[Blue Amberol Records|Blue Amberol]] cylinder box lid]]\nOn March 20, 1900, Thomas B. Lambert was granted a US patent (645,920) that described a process for mass-producing cylinders made from [[celluloid]], an early hard plastic. ({{ill|Henri Jules Lioret|fr}} of France was producing celluloid cylinders as early as 1893, but they were individually recorded rather than molded.) That same year, the Lambert Company of Chicago began selling cylinder records made of the material. They would not break if dropped and could be played thousands of times without wearing out, although the choice of the bright pink color of early cylinders was arguably a marketing error. The color was changed to black in 1903, but brown and blue cylinders were also produced. The coloring was purportedly because the dye reduced [[surface noise]]. Unlike wax, the hard, inflexible material could not be shaved and recorded over, but it had the advantage of being nearly permanent.<ref>{{cite web|url=http://www.cylinder.de/guide_lambert-cylinders.html|title=Norman Bruderhofer's Cylinder Guide \u2013 Lambert Cylinders|website=cylinder.de}}</ref><ref>{{cite web|url=http://www.phonographcylinders.com/lambert-replica-cylinder.php|title=Lambert Replica Cylinders|website=phonographcylinders.com|access-date=2012-03-15|url-status=dead|archive-url=https://web.archive.org/web/20120324014701/http://www.phonographcylinders.com/lambert-replica-cylinder.php|archive-date=2012-03-24}}</ref>\n\nSuch "indestructible" style cylinders are one of the most durable forms of sound recording produced in the entire era of analog audio media; they can withstand a greater number of playbacks before wearing out than later media such as the [[vinyl record]] or [[Compact Cassette|audio tape]]. Their only serious shortcoming is that the celluloid slowly shrinks over the years, so that if it is on a core of plaster, metal or other very unyielding material, the ever-increasing tension can ultimately cause the celluloid to split lengthwise. A typical Lambert cylinder will have shrunk by approximately 3 mm in length in the 100 years or so since its manufacture. (The actual amount is very dependent on storage conditions.) Thus the grooves will no longer be 100 per inch, and the cylinder will skip if played on a typical feed-screw-type machine. The diameter will also have shrunk and many such cylinders will no longer fit on the [[mandrel]] unless very carefully reamed to fit. Such cylinders can still be played quite satisfactorily on suitable modern equipment. The Lambert company was put out of business in 1906 due to repeated actions from Edison for patent infringement, which Lambert had not actually committed. It was the cost of defending the actions that eventually sank Lambert.{{Citation needed|date=May 2015}}\n\nThis superior technology was licensed by the Indestructible Record Company<ref>{{Cite web|date=2005-11-16|title=Cylinder Preservation and Digitalization Project|url=http://cylinders.library.ucsb.edu/history-indestructible.php|url-status=live|access-date=June 19, 2021|website=Indestructible Records {{!}} UCSB Cylinder Audio Archive|publisher=[[University of California, Santa Barbara Library]]}}</ref> in 1906 and [[Columbia Records|Columbia Phonograph Company]] in 1908. The [[Edison Bell]] company in Europe had separately licensed the technology and were able to market Edison's titles in both wax (popular series) and celluloid (indestructible series).{{sfn|Read|Welch|1976|page=146}} Lambert was able to license the process because the patent was not owned by the now defunct Lambert Company, but by Lambert himself.{{citation needed|date=December 2016}}\n\nIn late 1908, Edison had introduced wax cylinders that played for nominally 4 minutes (instead of the usual 2) under the ''Amberol'' brand. They were made from a harder (and more fragile) form of wax to withstand the smaller stylus used to play them. The longer playing time was achieved by shrinking the groove size and spacing them twice as close together. In 1912, the Edison company eventually acquired Lambert's patents to the celluloid technology, and almost immediately started production under a variation of their existing ''Amberol'' brand as ''Edison Blue Amberol Records''.<ref>{{cite web|url=http://www.cylinder.de/guide_blue-amberol-cylinders.html|title=The Cylinder Archive \u2013 Cylinder Guide: Amberol and 4-minute Indestructible Cylinders}}</ref> These new celluloid recordings were given a core made from [[plaster of Paris]]. The celluloid material itself was blue, but purple was introduced in 1919, "... for more sophisticated selections". The use of camphor in Edison's celluloid base rendered it more stable, and the plaster core provided further resistance to possible shrinkage, but the playing surface is still liable to split if stored in less than ideal conditions; however, the groove pitch rarely changes. The plaster core itself can deteriorate in conditions that are too damp or too dry. Nevertheless, most Blue Amberol cylinders are, today, quite playable on antique phonographs or modern equipment alike (although the plaster core may need some reaming).{{citation needed|date=December 2016}}\n\nEdison made several designs of phonographs both with internal and external horns for playing these improved cylinder records. The internal horn models were called ''Amberolas''. Edison marketed its "Fireside" model phonograph with a gearshift and a 'model K' reproducer with two styli that allowed it to play both 2-minute and 4-minute cylinders.<ref>Model Number taken directly from actual Fireside reproducer.</ref> Conversion kits were produced for some of the later model 2-minute phonographs adding a gear change and a second 'model H' reproducer. These kits were shipped with a set of 12 (wax) Amberol cylinders in distinctive orange boxes. The purchaser had no choice as to the titles.{{citation needed|date=December 2016}}", "Phonograph cylinder --- Introduction ---|Disc records": "In the era before [[World War I]], phonograph cylinders and [[gramophone record|disc records]] competed with each other for public favor.\n\nThe audio fidelity of a sound groove is improved{{Clarify|date=August 2019}} if it is engraved on a cylinder due to better linear tracking.{{Explain|date=August 2019}} This was not resolved{{dubious|date=August 2019}} until the advent of [[RIAA equalization|RIAA Equalization]] in the early 1940s\u2014by which time it had already been rendered academic, as cylinder production stopped with Edison's last efforts in October 1929.", "Phonograph cylinder --- Introduction ---|Decline": "[[File:PhonographCylinders.JPG|thumb|Disc records and cylinders]]\nCylinder records continued to compete with the growing disc record market into the 1910s, when discs won the commercial battle. In 1912, [[Columbia Records]], which had been selling both discs and cylinders, dropped the cylinder format, while Edison introduced his unique{{clarify|date=August 2019}} [[Edison Disc Record|Diamond Disc]] format. Beginning in 1915, new Edison cylinder issues were simply dubs of Edison discs and therefore had lower audio quality than the disc originals.{{Explain|date=August 2019}} Although his cylinders continued to be sold in steadily dwindling and eventually minuscule quantities, Edison continued to support owners of cylinder phonographs by making new titles available in that format until the company ceased manufacturing all records and phonographs in November 1929.<!-- presumably still available into October, but no new titles added after mid-year. --><ref name="congress" />", "Phonograph cylinder --- Introduction ---|Later applications": "[[File:Wax cylinder in Dictaphone.jpg|thumb|Cylinder on Dictaphone dictation machine (c. 1922). The recording head moved left to right. The black lines are shiny gaps between tracks. Each cylinder could record 1,200 to 1,500 words. They could be reused 100 to 120 times by putting them in a machine that erased them by shaving off the surface.]]\n\nCylinder phonograph technology continued to be used for [[Dictaphone]] and Ediphone recordings for office use for decades.<ref name="Dictaphone">{{Cite web|url=http://www.soundrecordinghistory.net/history-of-sound-recording/history-of-dictaphone/|title=History of Dictaphone|access-date=2018-01-12|author=Tim Gracyk|date=2018|work=History of Sound Recording Devices|publisher=Sound Recording History}}</ref>\n\nIn 1947, Dictaphone replaced wax cylinders with their [[Dictabelt]] technology, which cut a mechanical groove into a plastic belt instead of into a wax cylinder. This was later replaced by [[magnetic tape]] recording. However, cylinders for older style dictating machines continued to be available for some years, and it was not unusual to encounter cylinder dictating machines into the 1950s.<ref name="Dictabelt">{{Cite web|url=http://www.obsoletemedia.org/dictabelt/|title=History of Dictaphone|access-date=2018-01-12|first=Jason|last=Curtis|work=Museum of Obsolete Media|date=30 April 2013|publisher=Museum of Obsolete Media}}</ref>\n\nIn the late 20th and early 21st century, new recordings have been made on cylinders for the [[novelty effect]] of using obsolete technology. Probably the most famous of these are by [[They Might Be Giants]], who in 1996 recorded "I Can Hear You" and three other songs, performed without electricity, on an 1898 Edison wax recording studio phonograph at the [[Edison National Historic Site]] in [[West Orange, New Jersey]]. This song was released on ''[[Factory Showroom]]'' in 1996 and re-released on the 2002 compilation ''[[Dial-A-Song: 20 Years of They Might Be Giants]]''. The other songs recorded were "James K. Polk", "Maybe I Know", and "The Edison Museum", the last a song about the site of the recording. These recordings were officially released online as MP3 files in 2001.<ref name="giants">{{Cite web|url=https://www.theymightbegiants.com/factory-showroom|title=Factory Showroom|access-date=2018-01-12|date=2017|work=The Official Website of Brooklyn's Ambassadors of Love|publisher=They Might Be Giants}}</ref>\n\nSmall numbers of cylinders have been manufactured in the 21st century out of modern long-lasting materials. Two companies engaged in such enterprise are the Vulcan Cylinder Record Company of [[Sheffield]], England,<ref>{{cite web|url=http://www.phonographcylinders.com|title=New Phonograph Cylinder Records|publisher=Vulcan Cylinder Record Company|date=2002|access-date=2014-10-20}}</ref> and the Wizard Cylinder Records Company in [[Baldwin, Nassau County, New York|Baldwin, New York]].<ref>{{cite web|url=http://www.capsnews.org/apn2008-6.htm|title=The Wizard Cylinder Record Company|author=Peter N. Dilg|work=Canadian Antique Phonograph Society|date=November\u2013December 2008|access-date=2014-10-20}}</ref> Both appear to have started in 2002.\n\nIn 2010 the British [[steampunk]] band [[The Men That Will Not Be Blamed for Nothing]] released the track "Sewer", from their debut album, ''[[Now That's What I Call Steampunk! Volume 1]]'' on a wax cylinder in a limited edition of 40, of which only 30 were put on sale. The box set came with instructions on how to make your own cylinder player for less than \u00a320. The [[BBC]] covered the release on Television on [[BBC Click]], on [[BBC Online]], and on [[Radio 5 Live]].<ref>{{cite news| url=http://news.bbc.co.uk/1/hi/technology/10171206.stm | work=BBC News | title=Tech Know: A journey into sound | date=2010-05-27}}</ref>\n\nIn August 2010, [[Ash International]] and PARC released the first commercially available glow in the dark phonograph cylinder, a work by [[Michael Esposito (paranormal investigator)|Michael Esposito]] and [[Carl Michael von Hausswolff]], entitled ''The Ghosts of Effingham''. The cylinder was released in a limited edition of 150 copies, and was produced by Vulcan Records in Sheffield, England.{{citation needed|date=October 2017}}\n\nIn June 2017 the Cthulhu Breakfast Club podcast released a special limited wax cylinder edition of a show.<ref>{{Cite web|publisher=[[British Library]]|date=2017-05-25|title=Podcast on Wax Cylinder|url=https://twitter.com/BL_DramaSound/status/867737576056258561|url-status=live|archive-url=|archive-date=|access-date=|via=Twitter}}</ref>\n\nIn April 2019, the podcast ''[[Hello Internet]]'' released ten limited edition wax cylinder recordings.<ref>[http://www.hellointernet.fm/podcast/2019/4/24/hi-122-wax-cylinders "Wax cylinder episode"], ''[[Hello Internet]]'', April 2019</ref>"}},
{"article_title": "Music sequencer", "pageid": "127510", "revid": "1061441904", "timestamp": "2021-12-21T18:58:30Z", "history_paths": [["Music sequencer --- Introduction ---", "History"]], "categories": ["music sequencers", "electronic musical instruments", "midi", "music software", "sound production technology", "synthesiser modules", "articles containing video clips", "iranian inventions"], "heading_tree": {"Music sequencer --- Introduction ---": {"Overview": {"Modern sequencers": {}}, "Types of music sequencer": {"Realtime sequencer (realtime recording mode)": {}, "Analog sequencer": {}, "Step sequencer (step recording mode)": {}, "Software sequencer": {}}, "History": {"Early sequencers": {}, "Analog sequencers": {}, "Step sequencers": {}, "Early computers": {}, "Digital sequencers": {}, "{{vanchor|Music workstations}}": {}, "{{vanchor|Standalone CV/Gate sequencers}}": {}, "{{vanchor|MIDI sequencers}}": {}, "{{vanchor|Personal computers}}": {}, "Visual timeline of rhythm sequencers": {}}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Music sequencer --- Introduction ---|History": "{{See also|Category:Mechanical musical instruments|Music box#Evolving box production}}\n{{multiple image | align = right | direction = horizontal\n | image1   = Barrel-organ 1.png| width1 = 155\n | caption1 = '''Barrel with pins''' on a large stationary [[barrel organ]] <!-- worked by hydraulic power, from Solomon de Caus, Les Raisons des forces mouvantes (Frankfort-on-Main, (1615) -->\n | image2   = DrehorgelLochkarte.jpg| width2 = 109\n | caption2 = '''[[Music roll]]''' <br />on barrel organ\n | <!-- image3   = Welteorchestrion1862.jpg| width3 = 123 -->\n | <!-- caption3 = [[Orchestrion]] (1862) controlled by music roll -->\n | <!-- image4   = AeolianHammond Player Organ model BA, NYSFair 2011.jpg| width4 = 100 -->\n | <!-- caption4 = [[Hammond organ|Electric organ]] (1938) controlled by music roll]] -->\n}}<!-- NOTE: Too wide image layout is not practical. -->\n\nThe early music sequencers were sound producing devices such as [[:Category:Mechanical musical instruments|automatic musical instruments]], [[music box]]es, [[mechanical organ]]s, [[player piano]]s, and [[Orchestrion]]s. Player pianos, for example, had much in common with contemporary sequencers. Composers or arrangers transmitted music to [[piano roll]]s which were subsequently edited by technicians who prepared the rolls for mass duplication. Eventually consumers were able to purchase these rolls and play them back on their own player pianos.\n\nThe origin of automatic musical instruments seems remarkably old.  As early as the 9th century, the [[Persian people|Persian]] (Iranian) [[Ban\u016b M\u016bs\u0101]] brothers invented a [[hydropower]]ed [[organ (music)|organ]] using exchangeable cylinders with pins,<ref>\n{{cite journal\n | first     = Charles B. |last = Fowler\n | date      = October 1967\n | title     = The Museum of Music: A History of Mechanical Instruments\n | journal   = Music Educators Journal\n | volume    = 54 | issue = 2 | pages = 45\u201349\n | doi       = 10.2307/3391092  |jstor = 3391092\n |s2cid = 190524140\n }}\n</ref> and also an [[automation|automatic]] [[flute]] playing machine using [[steam power]],<ref name=Koetsier>\n{{cite journal\n | last1     = Koetsier |first1=Teun\n | year      = 2001\n | title     = On the prehistory of programmable machines: musical automata, looms, calculators\n | journal   = Mechanism and Machine Theory\n | volume    = 36 | issue = 5 | pages = 589\u2013603\n | doi       = 10.1016/S0094-114X(01)00005-2\n}}\n</ref><ref>\n{{cite book\n | author    = [[Banu Musa]] (authors)\n | editor    = [[Donald Routledge Hill]] (translator)\n | year      = 1979\n | title     = The book of ingenious devices (Kit\u0101b al-\u1e25iyal)\n | publisher = [[Springer Science+Business Media|Springer]]\n | isbn     = 9027708339\n | pages     = 76\u20137\n}}\n</ref> as described in their ''[[Book of Ingenious Devices#Mechanical musical machines|Book of Ingenious Devices]]''. The Banu Musa brothers' automatic flute player was the first [[Program (machine)|programmable]] music sequencer device,<ref>{{cite journal |last1=Long |first1=Jason |last2=Murphy |first2=Jim |last3=Carnegie |first3=Dale |last4=Kapur |first4=Ajay |title=Loudspeakers Optional: A history of non-loudspeaker-based electroacoustic music |journal=[[Organised Sound]] |date=12 July 2017 |volume=22 |issue=2 |pages=195\u2013205 |publisher=[[Cambridge University Press]] |doi=10.1017/S1355771817000103|doi-access=free }}</ref> and the first example of repetitive [[music technology]], powered by [[hydraulics]].<ref>{{cite journal |last1=Levaux |first1=Christophe |title=The Forgotten History of Repetitive Audio Technologies |journal=[[Organised Sound]] |date=12 July 2017 |volume=22 |issue=2 |publisher=[[Cambridge University Press]] |pages=187\u2013194 |doi=10.1017/S1355771817000097|doi-access=free }}</ref>\n\nIn 1206, [[Al-Jazari]], an [[List of inventions in the medieval Islamic world|Arab engineer]], invented programmable musical [[automata]],<ref name="Fowler 45\u201349">{{Cite journal|title=The Museum of Music: A History of Mechanical Instruments|first=Charles B.|last=Fowler|journal=Music Educators Journal|volume=54|issue=2|date=October 1967|pages=45\u201349|doi=10.2307/3391092|jstor=3391092|s2cid=190524140}}</ref> a "[[robot]] [[Musical ensemble|band]]" which performed "more than fifty facial and body actions during each musical selection."<ref>{{citation|title=The Museum of Music: A History of Mechanical Instruments |first=Charles B.|last=Fowler|journal=Music Educators Journal|volume=54|issue=2|date=October 1967|pages=45\u201349|doi=10.2307/3391092|publisher=MENC_ The National Association for Music Education|jstor=3391092|s2cid=190524140}}</ref> It was notably the first programmable [[drum machine]]. Among the four [[automaton]] musicians were two drummers. It was a drum machine where [[Wiktionary:peg|pegs]] ([[cam]]s) bump into little [[lever]]s that operated the percussion. The drummers could be made to play different rhythms and different drum patterns if the pegs were moved around.<ref name=Sharkey>[[Noel Sharkey]], [https://web.archive.org/web/20070629182810/http://www.shef.ac.uk/marcoms/eview/articles58/robot.html A 13th Century Programmable Robot (Archive)], [[University of Sheffield]].</ref>\n\nIn the 14th century, rotating cylinders with pins were used to play a [[carillon]] (steam organ) in Flanders,{{citation needed|date=November 2011}} and at least in the 15th century, [[barrel organ]]s were seen in the Netherlands.<ref>\n{{cite EB1911\n | wstitle   = Barrel-organ\n         | volume    = 3\n         | pages     = 432\u2013434\n         | first     = Kathleen\n         | last      = Schlesinger\n}}</ref>\n\n{{multiple image | align = right | direction = horizontal\n | image1   = Steinway piano - Duo-Art.ogv| width1 = 128\n | caption1 = [[Player piano]] (1920) controlled by [[piano roll]].\n | image2   = RCA Mark II Sound Synthesizer.jpg| width2 = 136\n | caption2 = [[RCA Mark II Sound Synthesizer|RCA Mark II]] (1957), <br />controlled via wide punched paper roll\n}}\nIn the late-18th or early-19th century, with technological advances of the [[Industrial Revolution]] various automatic musical instruments were invented. Some examples: [[music box]]es, [[barrel organ]]s and [[barrel piano]]s consisting of a barrel or cylinder with pins or a flat metal disc with punched holes; or [[mechanical organ]]s, [[player piano]]s and [[orchestrion]]s using [[book music]] / [[music roll]]s ([[piano roll]]s) with punched holes, etc.  These instruments were disseminated widely as popular entertainment devices prior to the inventions of [[phonograph]]s, [[radio]]s, and [[sound film]]s which eventually eclipsed all such home music production devices.\nOf them all, punched-paper-tape media had been used until the mid-20th century. The earliest programmable [[music synthesizer]]s including the [[RCA Mark II Sound Synthesizer]] in 1957<!-- for researching Mathematical Theory Of Music -->, and the Siemens Synthesizer in 1959, were also controlled via [[punch tape]]s similar to [[piano roll]]s.<ref name=rcamark2>\n{{cite web\n |title       = The RCA Synthesiser\n |url         = http://120years.net/machines/rca/\n |work        = 120 Years of Electronic Music (120years.net)\n |url-status     = live\n |archive-url  = http://archive.wikiwix.com/cache/20111026223002/http://120years.net/machines/rca/\n |archive-date = 2011-10-26\n|date = 2014-02-11\n }}\u2014([http://www.mathieubosi.com/zikprojects/120YearsOfElectronicMusic.pdf PDF version] {{webarchive|url=https://web.archive.org/web/20120402113013/http://www.mathieubosi.com/zikprojects/120YearsOfElectronicMusic.pdf |date=2012-04-02 }} is available)\n</ref><ref name=siemens>\n{{cite web\n |title       = Das Siemens-Studio f\u00fcr elektronische Musik von Alexander Schaaf und Helmut Klein\n |url         = http://www.deutsches-museum.de/sammlungen/ausgewaehlte-objekte/meisterwerke-vi/siemens-studio/\n |language    = de\n |publisher   = [[Deutsches Museum]]\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20130930175905/http://www.deutsches-museum.de/sammlungen/ausgewaehlte-objekte/meisterwerke-vi/siemens-studio\n |archive-date = 2013-09-30\n}}\n</ref><ref name=holmes2012>\n{{cite book\n |last             = Holmes\n |first            = Thom\n |chapter          = Early Synthesizers and Experimenters\n |chapter-url       = https://books.google.com/books?id=aT5nAQAAQBAJ&pg=PA175\n |title            = Electronic and Experimental Music: Technology, Music, and Culture\n |edition          = 4th\n |publisher        = Routledge\n |date = 2012\n |isbn             = 978-1-136-46895-7\n |pages            = [https://archive.org/details/electronicexperi00holm/page/190 190]\u2013[https://archive.org/details/electronicexperi00holm/page/192 192]\n}} See also excerpt from pp. 157-160 in [http://static1.squarespace.com/static/50e79ec7e4b07dba60068e4d/t/515704dce4b05239ba84e64c/1364657372465/Holmes4.pdf Chapter 6] of ''Early Synthesizers and Experimenters''.</ref>\n\n<!-- [[Image:Films on Oramics move in this direction (clip).png|thumb|132px|[[Drawn sound]]  films on [[Oramics]] (1957) <br />resembles strip chart]] -->\nAdditional inventions grew out of [[sound film]] audio technology. The [[drawn sound]] technique which appeared in the late 1920s, is notable as a precursor of today's intuitive [[graphical user interface]]s. In this technique, notes and various sound parameters are triggered by hand-drawn black ink waveforms directly upon the film substrate, hence they resemble piano rolls (or the 'strip charts' of the modern sequencers/DAWs). Drawn soundtrack was often used in early experimental electronic music, including the [[Variophone]] developed by Yevgeny Sholpo in 1930, and the [[Oramics]] designed by [[Daphne Oram]] in 1957, and so forth.\n\n \n{{multiple image | align = right | direction = horizontal\n | <!-- image1   = Buchla 250e Arbitrary Function Generator.jpg| width1 = 132 -->\n | <!-- caption1 = [[Buchla 200e|Buchla 250e]] Arbitrary Function Generator (2004)<br />seems influenced <br />by [[Raymond Scott#Electronics and research|Circle Machine]] -->\n | image2   = Buchla 100 series at NYU.jpg| width2 = 132\n | caption2 = <!-- One of the -->Earliest commercially available analog sequencers (bottom<!-- , 3\u00d78 step and 3\u00d716 step -->) on [[Buchla]] 100 (1964/1966)<ref name=holmes2008a>\n{{cite book\n | last      = Holmes | first = Thom\n | year      = 2008\n | title     = Electronic and experimental music: technology, music, and culture\n | edition   = 3rd\n | publisher = Routledge\n | isbn        = 978-0-415-95781-6\n | page      = [https://books.google.com/books?id=Q0uTAgAAQBAJ&q=Buchla+100+sequencer&pg=PA222#v=onepage 222]\n | quote     = <span style="font-size:90%;">Moog admired Buchla's work, recently stating that Buchla designed a system not only for "making new sounds but [for] making textures out of these sounds by specifying when these sounds could change and how regular those change would be."</span>\n}}\n</ref><!-- Temporarily comment out (can't re-verify enough): <ref name=miller2001>\n{{citation\n | last      = Miller | first = David\n | year      = 2001   | date  = May 9, 2001\n | title     = personal communication with Thom Holmes\n}}\n  </ref> -->\n | image3   = 1st commercial Moog synthesizer (1964, commissioned by the Alwin Nikolai Dance Theater of NY) @ Stearns Collection (Stearns 2035), University of Michigan.jpg| width3 = 132\n | caption3 = Moog sequencer module (top left, probably added after 1968) on <!-- the 1st commercial --> [[Moog modular synthesizer|Moog Modular]] (1964)\n}}\n{{Main|Analog sequencer}}\n{{expand section|date=April 2017}}\n\nDuring the 1940s\u20131960s, [[Raymond Scott]], an American composer of electronic music, invented various kind of music sequencers for his electric compositions.  The "Wall of Sound", once covered on the wall of his studio in New York during the 1940s\u20131950s, was an [[electro-mechanical]] sequencer to produce rhythmic patterns, consisting of stepping [[relay]]s (used on [[dial pulse]] [[telephone exchange]]), [[solenoid]]s, control switches, and tone circuits with 16 individual [[oscillator]]s.<ref name=wallofsound>\n{{cite web\n |title       = Wall of Sound (sequencer)\n |url         = http://raymondscott.com/1946.htm\n |work        = RaymondScott.com\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20111113023228/http://raymondscott.com/1946.htm\n |archive-date = 2011-11-13\n}}\n</ref>  Later, [[Robert Moog]] would explain it in such terms as "the whole room would go 'clack - clack - clack', and the sounds would come out all over the place".<ref name=memories/>\nThe Circle Machine, developed in 1959, had [[Incandescent light bulb|incandescent bulbs]] each with its own [[rheostat]], arranged in a ring, and a rotating arm with [[photocell]] scanning over the ring, to generate an arbitrary waveform. Also, the rotating speed of the arm was controlled via the brightness of lights, and as a result, arbitrary rhythms were generated.<ref name=circlemachine> \n{{cite web\n |title       = Circle Machine\n |url         = http://raymondscott.com/circle.html\n |work        = RaymondScott.com\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20110927232227/http://raymondscott.com/circle.html\n |archive-date = 2011-09-27\n}}\u2014includes 2 sound files: Raymond Scott's demonstration, and commercial soundtrack for new batteries of [[Ford Motors]].\n</ref>\nThe first electronic sequencer was invented by Raymond Scott, using [[thyratron]]s and [[relay]]s.<ref>[https://www.raymondscott.net/docs/RS-Artifacts.pdf Raymond Scott Artifacts], p. 13</ref>\n\n[[Clavivox]], developed since 1952, was a kind of keyboard synthesizer with sequencer.{{Verify source|date=November 2011|reason=Although it was quoted phrase from the article [[Clavivox]], "sequencer" function on Clavivox seems to be not found on any sources. Possibly it was confused with the film-based portamento function.}}  On its prototype, a [[theremin]] manufactured by young Robert Moog was utilized to enable [[portamento]] over 3-octave range, and on later version, it was replaced by a pair of [[photographic film]] and photocell for controlling the pitch by [[voltage]].<ref name=memories>\n{{cite web\n |last      = Moog\n |first      = Robert\n |title       = Memories of Raymond Scott\n |url         = http://raymondscott.com/moog.html\n |work        = RaymondScott.com\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20111106035451/http://raymondscott.com/moog.html\n |archive-date = 2011-11-06\n}}</ref>\n\nIn 1968 [[Ralph Lundsten]] and [[Leo Nilsson]] had a polyphonic synthesizer with sequencer called [[Andromatic]] built for them by [[Erkki Kurenniemi]].<ref>\n{{cite web\n |last      = St\u00e4dje\n |first      = J\u00f6rgen\n |date        = 2012-10-06\n |title       = Andromatic, den automatiska andromedaren\n |url         = http://www.idg.se/2.1085/1.445306/andromatic-den-automatiska-andromedaren\n |publisher   = International Data Group (IDG)\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20121007224640/http://www.idg.se/2.1085/1.445306/andromatic-den-automatiska-andromedaren\n |archive-date = 2012-10-07\n}}</ref>\n\n \n{{multiple image | align=right | direction=horizontal\n | <!-- header    = Step sequencers -->\n <!-- Image 1 -->\n | image1    = Wurlitzer Sideman (1959) disc sequencer.jpg| width1    = 130\n | caption1  = Electro-mechanical disc sequencer on [[Drum machine#Early drum machines|early drum machine]] <!-- , [[Wurlitzer]] Sideman --> (1959)\n <!-- Image 2 -->\n | image2    = Eko ComputeRhythm.png| width2    = 131\n | caption2  = [[Eko guitars|Eko]] ComputeRhythm (1972),<ref name="jarrography-Eko">\n{{cite web\n |title       = EKO Computerhythm (1972)\n |url         = http://www.jarrography.free.fr/details_equipement_audio.php?id_equip=117\n |work        = Jarrography - The ultimate Jean Michel Jarre discography\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20120503190624/http://www.jarrography.free.fr/details_equipement_audio.php?id_equip=117\n |archive-date = 2012-05-03\n}}\n</ref><ref name="synthmaster-Eko">\n{{cite web\n |title       = EKO Computerhythm\n |url         = http://www.synthmaster.de/ekodrum.htm\n |work        = SynthMaster.de\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20160304083316/http://www.synthmaster.de/ekodrum.htm\n |archive-date = 2016-03-04\n}}\n</ref> one of the earliest programmable drum machines\n <!-- Image 3 -->\n | image3    = Firstman SQ-01.png| width3    = 116\n | caption3  = [[Multivox#Digital sequencers|Firstman SQ-01]] (1980),<ref name="synrise-SQ01">\n{{cite web\n | title     = Multivox International\n | url       = http://www.synrise.de/docs/types/f/firstman.htm\n | language  = de| work      = SYNRISE\n | archive-url= https://web.archive.org/web/20030420170643/http://www.synrise.de/docs/types/f/firstman.htm\n | archive-date=2003-04-20\n}}\n</ref> one of the earliest step [[Bass synth|bass]] machines\n}}\n{{See also|Drum machine|Bass synth|Groovebox}}\n{{Confusing section|date=October 2011}}\n\nThe '''step sequencer'''s played rigid patterns of notes using a grid of (usually) 16 buttons, or steps, each step being 1/16 of a [[bar (music)|measure]]. These patterns of notes were then chained together to form longer compositions.  Sequencers of this kind are still in use, mostly built into [[drum machine]]s and [[groovebox]]es. They are monophonic by nature, although some are [[multi-timbral]], meaning that they can control several different sounds but only play one note on each of those sounds.{{clarify|date=October 2011}}\n\n {{Main|Computer music}}\n\n[[File:CSIRAC-Pano,-Melb.-Museum,-12.8.2008.jpg|thumb|265px|[[CSIRAC]] played the earliest [[computer music]] in 1951]]\nOn the other hand, software sequencers were continuously utilized since the 1950s in the context of [[computer music]], including computer-''played'' music (software sequencer), computer-''composed'' music ([[algorithmic music|music synthesis]]), and computer ''sound generation'' ([[sound synthesis]]). In June 1951, the first computer music ''Colonel Bogey'' was played on [[CSIRAC]], Australia's first digital computer.<ref name=csirac>{{cite web\n |title       = CSIRAC: Australia's first computer\n |url         = http://www.csiro.au/science/ps4f.html\n |publisher   = [[Commonwealth Scientific and Industrial Research Organisation]] (CSIRO)\n |location    = Australia\n |access-date  = 2007-12-21\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20071116112251/http://www.csiro.au/science/ps4f.html\n |archive-date = 2007-11-16\n}}</ref><ref name="bbc2008">{{cite news\n |last        = Fildes\n |first       = Jonathan\n |date        = 2008-06-17\n |title       = 'Oldest' computer music unveiled\n |url         = http://news.bbc.co.uk/1/hi/technology/7458479.stm\n |work        = [[BBC News Online]]\n |access-date  = 2008-06-18\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20090111225358/http://news.bbc.co.uk/1/hi/technology/7458479.stm\n |archive-date = 2009-01-11\n}}\u2014another oldest known recording of [[computer music|computer realized <!-- generated -->music]] played by the [[Ferranti Mark 1]], captured by [[BBC]] in Autumn, 1951; the songs ''[[Baa Baa Black Sheep]]'' and ''[[In the Mood]]''.</ref> In 1956, [[Lejaren Hiller]] at the [[University of Illinois at Urbana\u2013Champaign]] wrote one of the earliest programs for [[algorithmic music|computer music composition]] on [[ILLIAC]], and collaborated on the first piece, ''[[Illiac Suite]] for String Quartet'', with [[Leonard Issaction]].<ref name=hiller1981>{{cite journal\n | last      = Hiller | first = Lejaren\n | date      = Winter 1981\n | title     = Composing with Computer: A Progress Report\n | journal   = Computer Music Journal\n | volume    = 5 | number = 4\n| pages = 7\u201321\n | doi = 10.2307/3679501\n | jstor = 3679501\n }} <br />also available in\n{{cite book\n | editor    = Curtis Roads\n | title     = The Music Machine: Selected Readings from Computer Music Journal\n | pages     = [https://books.google.com/books?id=bqKfS3qQjMQC&q=Mathews&pg=PA75#v=onepage 75]\n | publisher = MIT Press (1989/1992)\n | isbn     = 978-0-262-68078-3\n| date = 1992-10-08\n }}</ref> In 1957 [[Max Mathews]] at [[Bell Labs]] wrote [[MUSIC-N|MUSIC]], the first widely used program for sound generation, and a 17-second composition was performed by the [[IBM 704]] computer. Subsequently, computer music <!-- and computer sound generation --> was mainly researched on the expensive [[mainframe computer]]s in computer centers, until the 1970s when [[minicomputer]]s and then [[microcomputer]]s became available in this field.\n\nIn Japan, experiments in computer music date back to 1962, when [[Keio University]] professor Sekine and [[Toshiba]] engineer Hayashi experimented with the [[:jp:TOSBAC|TOSBAC]] computer. This resulted in a piece entitled ''TOSBAC Suite''.<ref name="shimazu104">{{cite journal |last1=Shimazu |first1=Takehito |title=The History of Electronic and Computer Music in Japan: Significant Composers and Their Works |journal=Leonardo Music Journal |date=1994 |volume=4 |pages=102\u2013106 |doi=10.2307/1513190 |jstor=1513190 |s2cid=193084745 |url=https://www.semanticscholar.org/paper/35e86781e233b5f8c8c2930e854ac68dcc3b4c86 }}</ref>\n{{multiple image\n | image1   = 3C DDP-24 computer card rack side.jpg |width1=115\n | image2   = 3C DDP-24 computer card rack.JPG      |width2=143\n | <!-- image3   = 3C DDP-24 computer card rack rear.JPG |width3=120 -->\n | footer   = DDP-24 S Block (expansion card rack unit) that is assumed <!-- to had been --> the [[Analog-to-digital converter|A/D converters]] used  for GROOVE (1970) by Max Mathews.\n}} In 1965,<ref name=Ninke1965>{{citation\n | first     = William | last = Ninke\n | title     = Graphic 1: A Remote Graphical Display Console System\n | periodical= Proceedings of Fall Joint Computer Conference\n | volume    = 27\n | date = 1965\n}}</ref> Mathews and L. Rosler developed [[Graphic 1]], an interactive [[graphical sound]] system  (that implies sequencer) on which one could draw figures using a light-pen that would be converted into sound, simplifying the process of [[algorithmic composition|composing computer generated music]].<ref name=holmes2008b>{{cite book\n  | last  = Holmes | first = Thom\n  | year  = 2008\n  | chapter=Digital Synthesis and Computer Music\n  | title = Electronic and experimental music: technology, music, and culture\n  | pages = [https://books.google.com/books?id=hCthQ-bec-QC&q=Mathews+MUSIC+GROOVE+%22Graphic+1%22&pg=PA254#v=onepage 254]\n  | publisher = Taylor & Francis\n  | isbn  = 978-0-415-95781-6\n}}</ref><ref name=roads1980 /> It used [[PDP-5]] minicomputer for data input, and [[IBM 7090#IBM 7094|IBM 7094]] mainframe computer for rendering sound. Also in 1970, Mathews and F. R. Moore developed the [[GROOVE]] (Generated Real-time Output Operations on [[CV/gate|Voltage-controlled]] Equipment) system,<ref name=groove>{{cite journal\n  | first1 = Mathews |last1 = Max V.\n  | first2 = Moore   |last2 = F.R.\n  | year   = 1970\n  | title  = GROOVE\u2014a program to compose, store, and edit functions of time\n  | journal= Communications of the ACM\n  | volume = 13 |issue=12\n}}</ref> a first fully developed [[algorithmic composition|music synthesis]] system for interactive composition (that implies sequencer) and realtime performance, using 3C/[[Honeywell]] [[DDP-24]]<ref name=vercoe>{{cite web |author1=Nyssim Lefford |author2=Eric D. Scheirer |author3=Barry L. Vercoe |name-list-style=amp |title=An Interview with Barry Vercoe |url=http://www.media.mit.edu/events/EMS/bv-interview.html |work=Experimental Music Studio 25 |publisher=Machine Listening Group, MIT Media Laboratory |url-status=live |archive-url=https://web.archive.org/web/20120331173352/http://www.media.mit.edu/events/EMS/bv-interview.html |archive-date=2012-03-31 }}</ref> (or DDP-224<ref name=bogdanov2001 />) minicomputers. It used a CRT display to simplify the management of music synthesis in realtime, 12bit [[Digital-to-analog converter|D/A]] for realtime sound playback, an interface for analog devices, and even several controllers including a musical keyboard, knobs, and rotating [[joystick]]s to capture realtime performance.<ref name=holmes2008b /><ref name=bogdanov2001>{{cite book\n  | last  = Bogdanov | first = Vladimir\n  | year  = 2001\n  | title = All music guide to electronica: the definitive guide to electronic music\n  | pages = [https://books.google.com/books?id=GJNXLSBlL7IC&q=GROOVE+Generated+Real-time+Output+Operations+on+Voltage-controlled+Equipment&pg=PT271#v=onepage 320]\n  | publisher = Backbeat Books\n  | isbn  = 978-0-87930-628-1\n}}</ref><ref name=roads1980>{{cite journal\n  | last  = Roads | first = Curtis\n  | title = Interview with Max Mathews\n  | date  = Winter 1980\n  | journal = Computer Music Journal\n  | volume=4 | number = 4 }} <br />in\n{{cite book\n  | editor= Curtis Roads\n  | title = The Music Machine: Selected Readings from Computer Music Journal\n  | pages = [https://books.google.com/books?id=bqKfS3qQjMQC&q=Mathews&pg=PA5#v=onepage 5]\n  | publisher = MIT Press (1989/1992)\n  | isbn  = 978-0-262-68078-3\n| date = 1992-10-08\n }}</ref>\n\n{{multiple image | align = right | direction = horizontal\n | image1   = EMS at MIM Sequencer.jpg| width1 = 125\n | caption1      = [[Electronic Music Studios|EMS]] Sequencer 256 (1971), branched from [[EMS Synthi 100|Synthi 100]].\n}}\n\n In 1971, [[Electronic Music Studios]] (EMS) released one of the first digital sequencer products as a module of [[EMS Synthi 100|Synthi 100]], and its derivation, [[Electronic Music Studios#Timeline of major products|Synthi Sequencer]] series.<ref name=synthi100>\n{{cite web | last      = Hinton | first      = Graham | year      = 2001 | title      = Synthi 100 (1971, formerly Digitana, aka the Delaware) | url      = http://www.ems-synthi.demon.co.uk/emsprods.html#synthi100 | publisher      = Electronic Music Studios (Cornwall) | url-status      = live | archive-url      = https://web.archive.org/web/20131031040324/http://www.ems-synthi.demon.co.uk/emsprods.html#synthi100 | archive-date      = 2013-10-31 }}\n</ref><ref name=seq256>\n{{cite web | last      = Hinton | first      = Graham | year      = 2001 | title      = Synthi Sequencer 256 (1971, formerly Synthi Moog Sequencer) | url      = http://www.ems-synthi.demon.co.uk/emsprods.html#seq256 | publisher      = Electronic Music Studios (Cornwall) | url-status      = live | archive-url      = https://web.archive.org/web/20131031040324/http://www.ems-synthi.demon.co.uk/emsprods.html#seq256 | archive-date      = 2013-10-31 }}</ref>\nAfter then, [[Oberheim Electronics|Oberheim]] released the DS-2 Digital Sequencer in 1974,<ref name=ds2>\n{{cite book\n |author       = J.Michmerhuizen\n |author2      = Thomas E. Oberheim\n |date         = June 1974\n |title        = DS-2 Digital Sequencer Instruction and Service Manual\n |url          = http://www.cem3374.com/docs/Manuals/Oberheim/DS2_O&SM.pdf\n |archive-url  = https://web.archive.org/web/20111218194017/http://www.cem3374.com/docs/Manuals/Oberheim/DS2_O%26SM.pdf\n |url-status     = dead\n |archive-date = 2011-12-18\n |access-date  = 2017-12-06\n}}\n</ref> and [[Sequential Circuits]] released Model 800 in 1977 <ref name=model800>\n{{cite web\n |title       = Model 800 Sequencer\n |url         = http://www.synthmuseum.com/sequ/seqseq80001.html\n |publisher   = SynthMuseum.com\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20111011114838/http://synthmuseum.com/sequ/seqseq80001.html\n |archive-date = 2011-10-11\n}}</ref>\n\n{{multiple image |direction=horizontal |align=right\n | image1   = Synclavier1 JB.jpg| width1 = 116\n | caption1 = [[Synclavier]] I (1977)<!--, a product version of Dartmouth Digital Synthesizer (1973\u20131975) -->\n | image2   = Fairlight green screen.jpg| width2 = 148\n | caption2 = Fairlight CMI (1979)<!--, a successor of Quasar (1975\u20131977) --> {{nowrap|supporting MCL <!-- language (software --> {{smaller|(sequencer)}}}}\n}}\n\n {{See also|Music workstation}}\n\nIn 1975, [[New England Digital]] (NED) released ABLE computer (microcomputer)<ref name=NEDhistory>\n{{cite web\n |title       = Synclavier Early History\n |url         = http://www.500sound.com/synclavierhistory.html\n |publisher   = Synclavier European Services\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20161114050731/http://www.500sound.com/synclavierhistory.html\n |archive-date = 2016-11-14\n}}\n</ref> as a dedicated data processing unit for Dartmouth Digital Synthesizer (1973), and based on it, later Synclavier series were developed.\n\nThe [[Synclavier|Synclavier I]], released in September 1977,<ref name=chadabe2001>\n{{cite journal\n |last      = Chadabe\n |first      = Joel\n |date        = May 1, 2001\n |title       = The Electronic Century Part IV: The Seeds of the Future\n |url         = http://emusician.com/tutorials/electronic_century4/\n |journal     = Electronic Musician\n |quote       = In September 1977, I bought the first Synclavier, although mine came without the special keyboard and control panel ... (see [http://emusician.com/tutorials/electronic_century4/ Fig. 1] on the page).\n |url-status     = dead\n |archive-url  = https://web.archive.org/web/20091002070017/http://emusician.com/tutorials/electronic_century4/\n |archive-date = October 2, 2009\n}}\n</ref>  was one of the earliest digital [[music workstation]] product with multitrack sequencer.  Synclavier series evolved throughout the late-1970s to the mid-1980s, and they also established integration of [[digital audio|digital-audio]] and music-sequencer, on their Direct-to-Disk option in 1984, and later Tapeless Studio system.\n\n{{multiple image | align = right | direction = horizontal\n | image1   = Fairlight II Page R.png| width1 = 125\n | caption1 = Page R on Fairlight\n}}\n\nIn 1982, renewed the [[Fairlight CMI]] Series II and added new sequencer software "Page R", which combined [[step sequencer|step sequencing]] with [[Sampling (music)|sample]] playback.<ref name=AudioMedia1996>\n{{cite magazine\n |title       = Fairlight- The Whole Story\n |url         = http://www.anerd.com/fairlight/fairlightstory.htm\n |magazine    = [[Audio Media (magazine)|Audio Media]]\n |issue       = January 1996\n |quote       = ''<!-- The first Fairlight CMI had been capable of recording a player's movements on keyboard and storing up to 50,000 notes, and it also contained something called MCL (Music Composition Language). However, MCL was criticised for being rather too complex and laborious for practical purposes. To resolve the problem, -->Fairlight launched the CMI Series II in 1982, which incorporated their now legendary Page R, the first serious music sequencer, which, according to Paine, "simply blew people away".''\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20170504030342/http://www.anerd.com/fairlight/fairlightstory.htm\n |archive-date = 2017-05-04\n}}\n</ref>\n\n[[Yamaha]]'s GS-1, their first [[FM synthesis|FM]] [[digital synthesizer]], was released in 1980.<ref>\n{{cite book\n | last    = Roads\n | first    = Curtis\n | year      = 1996\n | title     = The computer music tutorial\n | url       = https://books.google.com/books?id=nZ-TetwzVcIC&pg=PA226\n | publisher = [[MIT Press]]\n | page      = 226\n | isbn      = 0-262-68082-3\n | access-date= 2011-06-05\n}}</ref> To program the synthesizer, Yamaha built a custom computer workstation {{citation needed span|designed to be used as a sequencer for the GS-1|date=September 2017}}{{failed verification|date=September 2017}}. It was only available at Yamaha's headquarters in Japan ([[Hamamatsu]]) and the United States ([[Buena Park]]).{{citation needed|date=September 2018}}\n\n While there were earlier microprocessor-based sequencers for digital polyphonic synthesizers,<ref group=note name=Microprocessor_based_sequencer_in_mid1970s>\nIn 1974-1975, Australian computer music engineer Tony Furse developed the MC6800-based [[Fairlight CMI#Details|Qasar M8]] with a software sequencer [[Fairlight CMI#MUSEQ 8|MUSEQ 8]], with a minimum price of $8,000. In 1976, it was licensed to [[Fairlight (company)|Fairlight Instruments Pty Ltd.]], and eventually Fairlight CMI was released in 1979. (For details, see [[Fairlight CMI]])<br />\nAlso in 1975, [[New England Digital]] released original microprocessor-based [[Synclavier#Processor|ABLE computer]] (utilizing mini-computer architecture) as a future migration target of Dartmouth Digital Synthesizer. Their commercial version of digital synthesizer, [[Synclavier#Black panel models|Synclavier I]] was first shipped in 1977. (For details, see [[Synclavier]])\n</ref><!-- FALSEHOOD (both music & ASCII keyboard entries are supported): they were based on keyboard entry, and --> their early products tended to prefer the newer internal digital buses than the old-style analogue CV/Gate interface once used on their prototype system. Then in the early-1980s, they also re-recognized the needs of [[CV/Gate]] interface, and [[List of music sequencers#Proprietary digital interfaces (pre MIDI era)|supported it along with MIDI as options]].\n\n{{multiple image | align = right | direction = horizontal\n | image2   = Roland MC-8.jpg | width2 = 139\n | caption2 = [[Roland MC-8 Microcomposer]] (1977)\n | <!-- image3   = Roland MC-4 Microcomposer.jpg| width3 = 129 -->\n | <!-- caption3 = [[Roland MC-4 Microcomposer|Roland MC-4]] (1981), a successor of the [[Roland MC-8 Microcomposer|MC-8]] (1977)]] -->\n}}\nIn 1977, [[Roland Corporation]] released the [[Roland MC-8 Microcomposer|MC-8 Microcomposer]], also called ''[[computer music]] composer'' by Roland. It was an early stand-alone, [[microprocessor]]-based, digital CV/Gate sequencer,<ref name="russ">{{cite book\n | last      = Russ\n         |first      = Martin\n | year      = 2008\n | title     = Sound Synthesis and Sampling\n | url       = https://books.google.com/books?id=_D2cTt5DPmEC&pg=PA346\n | publisher = [[Focal Press]]\n | isbn     = 978-0240521053\n | page      = 346\n | access-date = 21 June 2011\n}}</ref><ref name="russ2012">{{cite book | last      = Russ         |first      = Martin | year      = 2012 | title     = Sound Synthesis and Sampling | url       = https://books.google.com/books?id=X9h5AgAAQBAJ&pg=PA192 | publisher = [[CRC Press]] | isbn     = 978-1136122149 | page      = 192 | access-date = 26 April 2017}}</ref> and an early [[Polyphony and monophony in instruments|polyphonic]] sequencer.<ref>Paul Th\u00e9berge (1997), [https://books.google.com/books?id=asBnYmKKz6kC&pg=PA223 ''Any Sound You Can Imagine: Making Music/Consuming Technology'', page 223], [[Wesleyan University Press]]</ref><ref>Herbert A. Deutsch (1985), [https://books.google.com/books?id=tjEJAQAAMAAJ ''Synthesis: an introduction to the history, theory & practice of electronic music''], page 96, [[Alfred Music]]</ref> It equipped a [[keypad]] to enter [[Musical note|notes]] as numeric codes, 16 [[Kilobyte|KB]] of [[Random access memory|RAM]] for a maximum of 5200 notes (large for the time), and a [[polyphony]] function which allocated multiple pitch [[CV/Gate|CVs]] to a single [[CV/Gate|Gate]].<ref name="SOS Nov. 2004">\n{{cite journal\n |last      = Reid\n |first      = Gordon\n |title       = The History Of Roland Part 1: 1930-1978\n |url         = http://www.soundonsound.com/sos/nov04/articles/roland.htm\n |issue       = Nov 2004\n |journal     = [[Sound on Sound]]\n |access-date  = 2011-06-19\n |url-status     = live\n |archive-url  = https://web.archive.org/web/20110629214447/http://www.soundonsound.com/sos/nov04/articles/roland.htm\n |archive-date = 2011-06-29\n}}\n</ref> It was capable of eight-channel polyphony, allowing the creation of [[polyrhythm]]ic sequences.<ref name="sos">[[Chris Carter (British musician)|Chris Carter]], [http://www.chriscarter.co.uk/content/sos/roland_mc8.html ROLAND MC8 MICROCOMPOSER] {{webarchive|url=https://web.archive.org/web/20170420095502/http://www.chriscarter.co.uk/content/sos/roland_mc8.html |date=2017-04-20 }}, ''[[Sound on Sound]]'', Vol.12, No.5, March 1997</ref><ref name="russ"/><ref name="russ2012"/> The MC-8 had a significant impact on popular [[electronic music]], with the MC-8 and its descendants (such as the [[Roland MC-4 Microcomposer]]) impacting popular electronic music production in the 1970s and 1980s more than any other family of sequencers.<ref name="sos"/> The MC-8's earliest known users were [[Yellow Magic Orchestra]] in 1978.<ref name="discogs_ymo_lp">{{Discogs release|453067|Yellow Magic Orchestra\u2014Yellow Magic Orchestra}}</ref><!-- VERIFICATION FAILED: they created new sounds not possible until then.{{Peacock term|date=October 2011}}<ref name="billboard_1979">\n{{cite journal\n | title     = Artists and producers strive for inroads overseas\n | url       = https://books.google.com/books?id=_iQEAAAAMBAJ&pg=PT61\n | journal   = [[Billboard (magazine)|Billboard]]\n | publication-date = 26 May 1979\n | volume    = 91 | issue = 20 | page = 61\n | issn      = 0006-2510\n | access-date = 2011-05-29\n}}</ref>{{Failed verification|date=October 2011|reason=Given article didn't mentioned on "Roland MC-8".}} -->\n\n {{Main|MIDI}}\n{{See also|Comparison of MIDI standards|Comparison of MIDI editors and sequencers|Groovebox}}\n\nIn June 1981, [[Roland Corporation]] founder [[Ikutaro Kakehashi]] proposed the concept of standardization between different manufacturers' instruments as well as computers, to [[Oberheim Electronics]] founder [[Tom Oberheim]] and [[Sequential Circuits]] president [[Dave Smith (engineer)|Dave Smith]]. In October 1981, Kakehashi, Oberheim and Smith discussed the concept with representatives from [[Yamaha]], [[Korg]] and [[Kawai (company)|Kawai]].<ref name="chadab5100">{{cite journal|last=Chadabe|first=Joel|author-link=Joel Chadabe|date=1 May 2000|title=Part IV: The Seeds of the Future|journal=Electronic Musician|publisher=Penton Media|volume=XVI|issue=5|url=http://www.emusician.com/gear/0769/the-electronic-century-part-iv-the-seeds-of-the-future/145415|url-status=dead|archive-url=https://web.archive.org/web/20120928230435/http://www.emusician.com/gear/0769/the-electronic-century-part-iv-the-seeds-of-the-future/145415|archive-date=28 September 2012}}</ref> In 1983, the [[MIDI|MIDI standard]] was unveiled by Kakehashi and Smith.<ref>{{cite web|url=http://www.grammy.com/news/technical-grammy-award-ikutaro-kakehashi-and-dave-smith|title=Technical GRAMMY Award: Ikutaro Kakehashi And Dave Smith|date=29 January 2013|url-status=live|archive-url=https://web.archive.org/web/20160822073641/http://www.grammy.com/news/technical-grammy-award-ikutaro-kakehashi-and-dave-smith|archive-date=22 August 2016}}</ref><ref>{{cite web|url=http://www.grammy.com/videos/technical-grammy-award-recipients-ikutaro-kakehashi-and-dave-smith-at-special-merit-awards|title=Ikutaro Kakehashi, Dave Smith: Technical GRAMMY Award Acceptance|date=9 February 2013|url-status=live|archive-url=https://web.archive.org/web/20141209022049/http://www.grammy.com/videos/technical-grammy-award-recipients-ikutaro-kakehashi-and-dave-smith-at-special-merit-awards|archive-date=9 December 2014}}</ref> The first MIDI sequencer was the Roland MSQ-700, released in 1983.<ref>{{cite web |url=https://www.roland.com/ca/company/history/ |title=Roland - Company - History - History |access-date=2017-05-17 |url-status=live |archive-url=https://web.archive.org/web/20170712075811/https://www.roland.com/ca/company/history/ |archive-date=2017-07-12 }}</ref>\n\nIt was not until the advent of MIDI that [[general-purpose computer]]s started to play a role as sequencers. Following the widespread adoption of MIDI, computer-based MIDI sequencers were developed. MIDI-to-[[CV/Gate]] converters were then used to enable [[analogue synthesizer]]s to be controlled by a MIDI sequencer.<ref name="russ2012"/> Since its introduction, MIDI has remained the musical instrument industry standard interface through to the present day.<ref name="fact">[http://www.factmag.com/2017/04/02/ikutaro-kakehashi-life/ The life and times of Ikutaro Kakehashi, the Roland pioneer modern music owes everything to] {{webarchive|url=https://web.archive.org/web/20170403005512/http://www.factmag.com/2017/04/02/ikutaro-kakehashi-life/ |date=2017-04-03 }}, ''[[Fact (UK magazine)|Fact]]''</ref>\n\n {{See also|MIDI|Computer music|Sampler (musical instrument)|Audio sequencer|Music tracker}}\n\nIn 1978, Japanese [[personal computer]]s such as the <!-- [[Sharp MZ]] and -->[[Hitachi]] [[:ja:\u30d9\u30fc\u30b7\u30c3\u30af\u30de\u30b9\u30bf\u30fc|Basic Master]] equipped the low-bit [[digital to analogue converter|D/A converter]] to generate sound which can be sequenced using [[Music Macro Language]] (MML).<ref name="BASIC MASTER">\n{{cite document | last1     =Kunihiko | first1     =Nagai | last2     =Teruhiro | first2     =Takezawa | last3     =Kazuma | first3     =Yoshimura | last4     =KaTsutoshi | first4     =Tajima | date     =April 1979 | title     =Micro computer BASIC MASTER (MB-6880)  | url     =http://www.hitachihyoron.com/jp/pdf/1979/04/1979_04_26.pdf | language     =ja | quote     ={{smaller|'''''{{nowrap|2.\u7279\u9577}}''' ... (4) \u30b9\u30d4\u30fc\u30ab\u30fc\u3092\u5185\u8535\u3057\u3066\u304a\u308a\u3001\u30d7\u30ed\u30b0\u30e9\u30e0\u306b\u3088\u308b\u97f3\u697d\u306e\u81ea\u52d5\u6f14\u594f\u304c\u53ef\u80fd\u3067\u3042\u308b\u3002 / '''\u8868 I''' \u300c\u30d9\u30fc\u30b7\u30c3\u30af\u30de\u30b9\u30bf\u30fc\u300d\u306e\u4e3b\u306a\u4ed5\u69d8\u4e00\u89a7 ... \u97f3\u697d\u767a\u751f\u6a5f\u80fd: 5\u30d3\u30c3\u30c8D/A\u5909\u63db\u306e\u30b9\u30d4\u30fc\u30ab\u30fc\u518d\u751f / '''{{nowrap|4.3 \u97f3\u697d\u767a\u751f\u6a5f\u80fd}}''' ...'' | url-status     =live | archive-url     =https://web.archive.org/web/20170915071518/http://www.hitachihyoron.com/jp/pdf/1979/04/1979_04_26.pdf | archive-date     =2017-09-15 }}\n}} <br />Published on: {{cite journal | title     = Special Features: Micro computer and its application<!-- A micro-computer, the application method --> | url     = http://www.hitachihyoron.com/jp/archive/1970s/1979/04.html | journal     = Hitachi Hyoron | issue     = April 1979 | location     = Japan | publisher     = [[Hitachi|Hitachi, Ltd]] | access-date     = 15 September 2017 | url-status     = live | archive-url     = https://web.archive.org/web/20170915071500/http://www.hitachihyoron.com/jp/archive/1970s/1979/04.html | archive-date     = 15 September 2017 }}</ref> This was used to produce [[chiptune]] [[video game music]].<ref name="shimazu104"/>\n\n{{multiple image | align = right | direction = horizontal\n | image1   = Moog Song Producer (1983, SN 1366, MIDI & CV-Gate interface for Commodore 64) on Lab Series SynAmp prototype (1978, SN E0471), at Cantos Music Foundation in 2009.jpg | width1 = 125\n | caption1 = <div style="line-height:120%;">Moog Song Producer (1983) {{smaller|MIDI & CV/Gate interface <!-- for [[Commodore 64]] --> on <!-- Lab Series --> SynAmp <!-- prototype (1978) -->}}</div>\n}}\n\nIt was not until the advent of [[MIDI]], introduced to the public in 1983, that [[general-purpose computer]]s really started to play a role as software sequencers.<ref name="russ2012"/> [[NEC]]'s personal computers, the [[PC-88]] and [[PC-98]], added support for [[MIDI]] sequencing with MML programming in 1982.<ref name="shimazu104"/> In 1983, [[Yamaha CX5M|Yamaha modules]] for the [[MSX]] featured music production capabilities,<ref>Martin Russ, [https://books.google.com/books?id=X9h5AgAAQBAJ&pg=PA84 ''Sound Synthesis and Sampling'', page 84], [[CRC Press]]</ref><ref name="ellis"/> real-time [[FM synthesis]] with sequencing, MIDI sequencing,<ref>{{cite book   | title     = Yamaha Music Computer CX5M Owner's Manual   | url     = http://download.yamaha.com/api/asset/file/?language=hu&site=hu.yamaha.com&asset_id=4605   | publisher     = Yamaha   | ref     = {{sfnref|CX5M Owner's Manual}}   | url-status     = dead   | archive-url     = https://web.archive.org/web/20151022170650/http://download.yamaha.com/api/asset/file/?language=hu&site=hu.yamaha.com&asset_id=4605   | archive-date     = 2015-10-22   | access-date     = 2018-12-26   }}</ref><ref name="ellis">David Ellis, [http://www.muzines.co.uk/articles/yamaha-cx5m/1481 Yamaha CX5M] {{webarchive|url=https://web.archive.org/web/20171026002632/http://www.muzines.co.uk/articles/yamaha-cx5m/1481 |date=2017-10-26 }}, ''Electronics & Music Maker'', October 1984</ref> and a [[graphical user interface]] for the software sequencer.<ref>{{cite book|url=https://archive.org/details/CX5MFlyer|title=Yamaha CX5M Music Computer Flyer (GB)|last=Yamaha|date=5 May 1984|access-date=5 May 2018|via=Internet Archive}}</ref><ref name="ellis"/> Also in 1983, [[Roland Corporation]]'s CMU-800 [[sound module]] introduced music synthesis and sequencing to the PC, [[Apple II]],<ref>[http://www.vintagesynth.com/roland/cmu800.php Roland CMU-800] {{webarchive|url=https://web.archive.org/web/20170604041554/http://www.vintagesynth.com/roland/cmu800.php |date=2017-06-04 }}, Vintage Synth Explorer</ref> and [[Commodore 64]].<ref>[https://www.theregister.co.uk/Print/2013/08/26/part_two_midi_spec_1_is_30_happy_birthday_musical_instrument_digital_interface/ Happy birthday MIDI 1.0: Slave to the rhythm] {{webarchive|url=https://web.archive.org/web/20171026002557/http://www.theregister.co.uk/Print/2013/08/26/part_two_midi_spec_1_is_30_happy_birthday_musical_instrument_digital_interface/ |date=2017-10-26 }}, ''[[The Register]]''</ref>\n\nThe spread of MIDI on personal computers was facilitated by Roland's [[MPU-401]], released in 1984. It was the first MIDI-equipped PC [[sound card]], capable of MIDI sound processing<ref name="emusician-mpu"/> and sequencing.<ref>{{cite web|url=http://www.piclist.com/techref/io/serial/midi/mpu.html|title=Programming the MPU-401|website=www.piclist.com|access-date=5 May 2018|url-status=live|archive-url=https://web.archive.org/web/20170506080336/http://www.piclist.com/techref/io/serial/midi/mpu.html|archive-date=6 May 2017}}</ref><ref>[ftp://ftp.oldskool.org/pub/drivers/Roland/MPU-401%20technical%20reference%20manual.pdf MIDI PROCESSING UNIT MPU-401 TECHNICAL REFERENCE MANUAL], [[Roland Corporation]]</ref> After Roland sold MPU [[sound chip]]s to other sound card manufacturers,<ref name="emusician-mpu">[http://www.textfiles.com/music/midi-em.txt MIDI INTERFACES FOR THE IBM PC] {{webarchive|url=https://web.archive.org/web/20151021050032/http://textfiles.com/music/midi-em.txt |date=2015-10-21 }}, ''[[Electronic Musician]]'', September 1990</ref> it established a universal standard MIDI-to-PC interface.<ref>Peter Manning (2013), [https://books.google.com/books?id=ryet1i-8OlYC ''Electronic and Computer Music''], page 319, [[Oxford University Press]]</ref> Following the widespread adoption of MIDI, computer-based [[Comparison of MIDI editors and sequencers|MIDI software sequencers]] were developed.<ref name="russ2012"/>\n\n{{multiple image | align = right | direction = horizontal\n | image2   = Milkytracker Instrument.jpg| width2 = 125\n | caption2 = [[Music tracker|Tracker]] software\n}}\n\nIn 1987, software sequencers called [[Tracker (music software)|trackers]] were developed to realize the low-cost integration of sampling sound and interactive digital sequencer as seen on [[Fairlight CMI]] II "Page R". They became popular in the 1980s and 1990s as simple sequencers for creating [[Video game music|computer game music]], and remain popular in the [[demoscene]] and [[chiptune]] music.\n\n \n{{Main|Drum machines|Groovebox|Beat slicing|Sampler (musical instrument)}}\n<div style="width:100%;overflow-x:scroll; margin-left:1em; border:1px solid #CCC;">\n{|style="margin:0;padding:0; font-size:88%;line-height:1.8ex;"\n|-style="vertical-align:top;"\n|[[Image:Welte Style 6 Concert Orchestrion No.198 (1895) - Assembly 06 (brighten, transformed & clipped).jpg|76px]]<br />\n[[:Category:Mechanical musical instruments|Mechanical<!-- musical instruments -->]] (pre-20th century)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Joseph Schillinger and the Rhythmicon.jpg|37px]]<br />\n[[Rhythmicon]] (1930)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|style="width:100px;"|<div style="width:70px;">[[Image:Wurlitzer Sideman drum machine (inside).jpg|57px]]</div>\n[[Drum machine|Drum machine]] <br />(1959\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|<div style="width:124px;">[[Image:Seeburg Select-A-Rhythm.jpg|122px]]<!-- [[Image:Maestro Rhythm MRQ-1.png|108px]] --></div><br />\n[[Transistor]]ized drum machine (1964\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Eko ComputeRhythm.png|100px]]<!-- |[[Image:Roland TR-808 drum machine.jpg|123px]] --><br />\nStep [[drum machine]] (1972\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Linn LM-1 Drum Computer.jpg|137px]]<br />\n[[Sampler (musical instrument)|Digital drum]] machine (1980\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|style="width:100px;"|[[File:Movement Computer Systems (MCS) Drum System II (or Percussion Computer II), circa 1981, United Kingdom - Knobcon 2014.jpg|100px]]<br />\n[[Groovebox|Groove machine]] (1981\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Fairlight II Page R.png|116px]]<br />\n"Page R" on [[Fairlight CMI|Fairlight<!-- CMI II Rev.10~ -->]] (1982)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Milkytracker Instrument.jpg|98px]]<br />\n[[Tracker (music software)|Tracker]] (1987\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|[[Image:Cubase6 Sample Editor beat slicing - Amen break.jpg|131px]]<!-- Deleted image removed: [[Image:Recycle mac screenshot.png|118px]] --><br />\n[[Beat slicing|Beat slicer]] (1990s\u2013)\n|[[Image:Cubase6 LoopMash 2 loop remixer (brighten).jpg|114px]]\n[[Loop (music)#Modern looping|Loop]] sequencer (1998\u2013)\n|<br /><br /><br />[[Image:Nuvola arrow right.svg|30px]]\n|style="width:140px;"|[[Image:Polyphonic note separation & manipulation.jpg|112px]]<br />\n[[Melodyne#Melodyne Direct Note Access|Note manipulation on audio tracks]] (2009\u2013)\n|}</div>"}},
{"article_title": "Mudbrick", "pageid": "140612", "revid": "1048553558", "timestamp": "2021-10-06T16:42:23Z", "history_paths": [["Mudbrick --- Introduction ---"], ["Mudbrick --- Introduction ---", "Ancient world"]], "categories": ["bricks", "sustainable building", "appropriate technology", "sustainable products", "soil-based building materials", "pre-pottery neolithic a"], "heading_tree": {"Mudbrick --- Introduction ---": {"Ancient world": {}, "Adobe": {}, "Banco": {}, "Mudbrick architecture worldwide": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Mudbrick --- Introduction ---": "{{short description|Unbaked earth used as building material blocks}}\n[[File:Mudbricks in Palestine 2011.jpg|thumb|New, unlaid mudbricks in the [[Jordan Valley (Middle East)|Jordan Valley]], [[West Bank]] (2011)]]\n[[File:Choghazanbil2.jpg|right|thumb|Mudbrick was used for the construction of [[Elam|Elamite]] [[ziggurat]]s\u2014some of the world's largest and oldest constructions. ''[[Choqa Zanbil]]'', a 13th-century BC [[ziggurat]] in [[Iran]], is similarly constructed from clay bricks combined with burnt bricks.<ref>Roman Ghirshman, La ziggourat de Tchoga-Zanbil (Susiane), Comptes-rendus des s\u00e9ances de l'Acad\u00e9mie des Inscriptions et Belles-Lettres, vol. 98 lien Issue 2, pp. 233\u2013238, 1954</ref>]]\n\nA '''mudbrick''' or '''mud-brick''' is an air-dried [[brick]], made of a mixture of [[loam]], [[mud]], [[sand]] and [[water]] mixed with a binding material such as [[rice]] husks or [[straw]]. Mudbricks are known from 9000 BCE, though since 4000 BC, bricks have also been fired, to increase their strength and durability.\n\nIn warm regions with very little [[timber]] available to fuel a [[kiln]], bricks were generally sun-dried. In some cases, brickmakers extended the life of mud bricks by putting fired bricks on top or covering them with [[stucco]].\n\n [[File:Mud-brick stamped with seal impression of raised relief of the Treasury of the Vizier. From Lahun, Fayum, Egypt. 12th Dynasty. The Petrie Museum of Egyptian Archaeology, London.jpg|thumb|Mud-brick stamped with seal impression of raised relief of the Treasury of the Vizier. From Lahun, Fayum, Egypt. 12th Dynasty. The Petrie Museum of Egyptian Archaeology, London]]\n\nThe history of mudbrick production and construction in the [[southern Levant]] may be dated as far back to the [[Pre-Pottery Neolithic A]] (e.g., PPNA Jericho).<ref name="Rosenberg2020">{{cite journal |last1=Rosenberg |first1=Danny |last2=Love |first2=Serena |last3=Hubbard |first3=Emily |last4=Klimscha |first4=Florian |title=7,200 years old constructions and mudbrick technology: The evidence from Tel Tsaf, Jordan Valley, Israel |journal=PLOS ONE |date=22 January 2020 |volume=15 |issue=1 |pages=e0227288 |doi=10.1371/journal.pone.0227288 |pmid=31968007 |pmc=6975557 |bibcode=2020PLoSO..1527288R |issn=1932-6203|doi-access=free }}</ref> These sun dried mudbricks, also known as adobe or just mudbrick, were made from a mixture of sand, clay, water and frequently temper (e.g. chopped straw and chaff branches), and were the most common method/material for constructing earthen buildings throughout the ancient Near East for millennia.<ref name="Rosenberg2020"/><ref>{{cite book |last1=Hasel |first1=Michael G. |editor1-last=Freedman |editor1-first=David Noel |title=Eerdmans dictionary of the Bible |date=2019 |publisher=William B. Eerdmans Publishing Company |isbn=978-1-4674-6046-0 |page=246-247? |chapter-url=https://www.google.com/books?id=Fq7qDwAAQBAJ&pg=PT246 |chapter=Architecture}}</ref><ref name="Morgenstein1998">{{cite journal |last1=Morgenstein |first1=Maury E. |last2=Redmount |first2=Carol A. |title=Mudbrick Typology, Sources, and Sedimentological Composition: A Case Study from Tell el-Muqdam, Egyptian Delta |journal=Journal of the American Research Center in Egypt |date=1998 |volume=35 |pages=129\u2013146 |doi=10.2307/40000466 |jstor=40000466 |url=https://www.jstor.org/stable/40000466 |issn=0065-9991}}</ref> Unfired mud-brick is still made throughout the world today, using both modern and traditional methods.<ref>{{cite journal |last1=Littman |first1=Robert |last2=Lorenzon |first2=Marta |last3=Silverstein |first3=Jay |title=With & without straw: How Israelite slaves made bricks |journal=Biblical Archaeology Review |date=2014 |volume=40 |issue=2 |url=https://www.researchgate.net/publication/287786412 |language=en}}</ref><ref>{{cite journal |last1=Emery |first1=Virginia L. |title=Mud-Brick |journal=UCLA Encyclopedia of Egyptology |date=2009 |volume=1 |issue=1 |url=https://escholarship.org/content/qt7v84d6rh/qt7v84d6rh.pdf}}</ref>\n\nThe 9000 BCE dwellings of [[Jericho]], were constructed from mudbricks,<ref>{{Cite book|last=Tellier|first=Luc-Normand|url=https://books.google.com/books?id=cXuCjDbxC1YC&q=jericho+9000+bc+bricks&pg=PA37|title=Urban World History: An Economic and Geographical Perspective|date=2009|publisher=PUQ|isbn=978-2-7605-2209-1|language=en}}</ref> affixed with mud, as would those at  numerous sites across the [[Levant]] over the following millennia. Well-preserved mudbricks from a site at Tel Tsaf, in the Jordan Valley, have been dated to 5200 BCE,<ref name=":0">{{Cite journal|last1=Rosenberg|first1=Danny|last2=Love|first2=Serena|last3=Hubbard|first3=Emily|last4=Klimscha|first4=Florian|date=2020-01-22|title=7,200 years old constructions and mudbrick technology: The evidence from Tel Tsaf, Jordan Valley, Israel|journal=PLOS ONE|language=en|volume=15|issue=1|pages=e0227288|doi=10.1371/journal.pone.0227288|issn=1932-6203|pmc=6975557|pmid=31968007|bibcode=2020PLoSO..1527288R|doi-access=free}}</ref> though there is no evidence that either site was the first to use the technology. Evidence suggests that the mudbrick composition at Tel Tsaf was stable for at least 500 years, throughout the middle [[Chalcolithic]] period.<ref name="Rosenberg2020"/>\n\nThe [[South Asia]]n inhabitants of [[Mehrgarh]] constructed and lived in mud-brick houses between 7000\u20133300 BC.<ref name="Possehl">Possehl, Gregory L. (1996)</ref> Mud bricks were used at more than 15 reported sites attributed to the 3rd millennium BC in the ancient [[Indus Valley Civilization]]. In the [[Mature Harappan]] phase fired bricks were used.<ref name="Bricks and Urbanism in Indus Valley">[https://www.academia.edu/1285495/Bricks_and_urbanism_in_the_Indus_Valley_rise_and_decline Bricks and urbanism in the Indus Valley rise and decline], bricks in antiquity</ref> \n\nThe [[Mesopotamia]]ns used sun-dried bricks in their city construction; <ref>Mogens Herman Hansen, ''A Comparative Study of Six City-state Cultures'', K\u00f8benhavns universitet Polis centret (2002) Videnskabernes Selskab, 144 pages {{ISBN|87-7876-316-9}}</ref> typically these bricks were flat on the bottom and curved on the top, called plano-convex mud bricks. Some were formed in a square mould and rounded so that the middle was thicker than the ends.  Some walls had a few courses of fired bricks from their bases up to the splash line to extend the life of the building.\n\nIn [[Minoan civilization|Minoan]] [[Crete]], at the [[Knossos]] site, there is [[archaeological]] evidence that sun-dried bricks were used in the [[Neolithic]] period (prior to 3400 BC).<ref>C. Michael Hogan, [http://www.themodernantiquarian.com/site/10854/knossos.html#fieldnotes ''Knossos fieldnotes'', Modern Antiquarian (2007)]</ref>\n\nSun dried mudbrick was the most common construction material employed in [[ancient Egypt]] during pharaonic times and were made in pretty much the same way for millennia. Mud from some locations required sand, chopped straw or other binders such as animal dung to be mixed in with the mud to increase durability and plasticity.<ref name="Morgenstein1998"/> Workers gathered mud from the Nile river and poured it into a pit. Workers then tramped on the mud while straw was added to solidify the mold.{{cn|date=December 2018}} The mudbricks were chemically suitable as fertilizer, leading to the destruction of many ancient Egyptian ruins, such as at [[Edfu]]. A well-preserved site is [[Amarna]].<ref>{{cite book|last=Hawkes|first=Jacquetta|author-link=Jacquetta Hawkes|title=Atlas of Ancient Archaeology|year=1974|publisher=[[McGraw-Hill Education|McGraw-Hill Book Company]]|isbn=0-07-027293-X|page=[https://archive.org/details/atlasofancientar00hawk/page/146 146]|url-access=registration|url=https://archive.org/details/atlasofancientar00hawk/page/146}}</ref> Mudbrick use increased at the time of [[Ancient Rome|Roman]] influence.<ref>Kathryn A. Bard and Steven Blake Shubert, ''Encyclopedia of the Archaeology of Ancient Egypt'', 1999, Routledge, 938 pages  {{ISBN|0-415-18589-0}}</ref>\n\nIn the [[Ancient Greece|Ancient Greek]] world, mudbrick was commonly used for the building of walls, fortifications and citadels, such as the walls of the Citadel of [[Troy]] (Troy II).<ref>[[Richard T. Neer|Neer, Richard. T]]., ''Art & archaeology of the Greek world: a new history, c. 2500-c.150 BCE,'' Second edition, Thames and Hudson, London, 2019, pp.23</ref> These mudbricks were often made with straw or dried vegetable matter.<ref>{{cite book |last1=Birge |first1=Darice Elizabeth |last2=Miller |first2=Stephen Gaylord |last3=Kraynak |first3=Lynn Harriett |last4=Miller |first4=S. G. |title=Excavations at Nemea. |date=1992\u20132018 |publisher=University of California Press |isbn=978-0-520-07027-1 |page=113n345 |url=https://www.google.com/books?id=ojTPxLcWGTwC&pg=PA113 |quote=Adding straw or dried vegetable matter to the clay of mudbricks was a common practice}}</ref>\n\n {{main article|Adobe}}\nIn areas of Spanish influence, mud-brick construction is called [[adobe]], and developed over time into a complete system of wall protection, flat roofing and finishes which in modern English usage is often referred to as ''adobe style'', regardless of the construction method.\n\n [[Image:Great Mosque of Djenn\u00e9 3.jpg|thumb|right|The Great Mosque of Djenn\u00e9 is a well-known [[Mosque]] located in [[Djenn\u00e9]], [[Mali]], and the largest mudbrick structure in the world.]]\n\nThe [[Great Mosque of Djenn\u00e9]], in central [[Mali]], is the world's largest mudbrick structure. It, like much [[Sahelian]] architecture, is built with a mudbrick called '''Banco''',<ref>{{cite web|url=http://www.kyoto-seika.ac.jp/researchlab/wp/wp-content/uploads/kiyo/pdf-data/no41/oussouby_sacko.pdf|title=Issues of Cultural Conservation and Tourism Development in the Process of World Heritage Preservation|last=SACKO|first=Oussouby|date=15 November 2015|publisher=Area Studies|access-date=7 October 2016}}</ref> a recipe of mud and [[grain]] husks, fermented, and either formed into bricks or applied on surfaces as a [[plaster]] like paste in broad strokes. This plaster must be reapplied annually.<ref>{{cite web|url=https://www.telegraph.co.uk/culture/art/3562677/Timbuktu-Mud-mud-glorious-mud.html|title=Timbuktu: Mud, mud, glorious mud|last=Bradbury|first=Dominic|date=30 October 2008|publisher=The Telegraph|access-date=25 February 2012}}</ref>\n\n <gallery>\nFile:Mudbrick production Niger 2007.jpg|Production of mudbricks for construction in [[Niger]], 2007.\nImage:RomaniaDanubeDelta MakingMaterialForCOnstructing0003jpg.JPG|Mudbrick is still used today, as seen here in the [[Romania]] [[Danube River]] Delta.\nFile:Zinder Old Town Niger 2007.jpg|The "Old Town" area of [[Zinder]], [[Niger]], with traditional painted mudbrick buildings.\nFile:Punjabi Home.JPG|A [[Punjabi people|Punjabi]] mudbrick home in [[Pakistan]].\nFile:Shibam Wadi Hadhramaut Yemen.jpg|Mudbrick [[tower house|high-rises]] in [[Shibam]], [[Yemen]].\nFile:Working mudbrick press 5.jpg|Making mudbricks near [[Cooktown, Australia]]\n</gallery>\n\n *{{annotated link|Cob (material)|Cob}}\n*{{annotated link|Earth structure}}\n*{{annotated link|Loam}}\n*{{annotated link|Rammed earth}}\n*{{annotated link|Sod house}}\n\n {{Reflist}}\n\n * Possehl, Gregory L. (1996). ''Mehrgarh'' in ''Oxford Companion to Archaeology'', edited by Brian Fagan. Oxford University Press.\n\n *[http://eartharchitecture.org Earth Architecture], website whose focus is contemporary issues in earth architecture.\n*[http://eartha.org.uk/ '''EARTHA''': ''Earth Architecture and Conservation in East Anglia''], British organisation that focuses on the proper maintenance and conservation of earth buildings in a region of the UK that has a long history of building with mud. Very experienced experts are contactable and there are regular demonstrations in the area.\n*[https://web.archive.org/web/20150912063954/http://one.revver.com/find/video/stepping+gently Video showing mud brick making], mud brick building and biolytic sewerage in South Africa.\n*[http://www.craterre.org/ '''CRAterre''': ''Centre de recherche architectural en terre''], French university research organisation dedicated to unfired earth construction\n\n{{Prehistoric technology|state=expanded}}", "Mudbrick --- Introduction ---|Ancient world": "[[File:Mud-brick stamped with seal impression of raised relief of the Treasury of the Vizier. From Lahun, Fayum, Egypt. 12th Dynasty. The Petrie Museum of Egyptian Archaeology, London.jpg|thumb|Mud-brick stamped with seal impression of raised relief of the Treasury of the Vizier. From Lahun, Fayum, Egypt. 12th Dynasty. The Petrie Museum of Egyptian Archaeology, London]]\n\nThe history of mudbrick production and construction in the [[southern Levant]] may be dated as far back to the [[Pre-Pottery Neolithic A]] (e.g., PPNA Jericho).<ref name="Rosenberg2020">{{cite journal |last1=Rosenberg |first1=Danny |last2=Love |first2=Serena |last3=Hubbard |first3=Emily |last4=Klimscha |first4=Florian |title=7,200 years old constructions and mudbrick technology: The evidence from Tel Tsaf, Jordan Valley, Israel |journal=PLOS ONE |date=22 January 2020 |volume=15 |issue=1 |pages=e0227288 |doi=10.1371/journal.pone.0227288 |pmid=31968007 |pmc=6975557 |bibcode=2020PLoSO..1527288R |issn=1932-6203|doi-access=free }}</ref> These sun dried mudbricks, also known as adobe or just mudbrick, were made from a mixture of sand, clay, water and frequently temper (e.g. chopped straw and chaff branches), and were the most common method/material for constructing earthen buildings throughout the ancient Near East for millennia.<ref name="Rosenberg2020"/><ref>{{cite book |last1=Hasel |first1=Michael G. |editor1-last=Freedman |editor1-first=David Noel |title=Eerdmans dictionary of the Bible |date=2019 |publisher=William B. Eerdmans Publishing Company |isbn=978-1-4674-6046-0 |page=246-247? |chapter-url=https://www.google.com/books?id=Fq7qDwAAQBAJ&pg=PT246 |chapter=Architecture}}</ref><ref name="Morgenstein1998">{{cite journal |last1=Morgenstein |first1=Maury E. |last2=Redmount |first2=Carol A. |title=Mudbrick Typology, Sources, and Sedimentological Composition: A Case Study from Tell el-Muqdam, Egyptian Delta |journal=Journal of the American Research Center in Egypt |date=1998 |volume=35 |pages=129\u2013146 |doi=10.2307/40000466 |jstor=40000466 |url=https://www.jstor.org/stable/40000466 |issn=0065-9991}}</ref> Unfired mud-brick is still made throughout the world today, using both modern and traditional methods.<ref>{{cite journal |last1=Littman |first1=Robert |last2=Lorenzon |first2=Marta |last3=Silverstein |first3=Jay |title=With & without straw: How Israelite slaves made bricks |journal=Biblical Archaeology Review |date=2014 |volume=40 |issue=2 |url=https://www.researchgate.net/publication/287786412 |language=en}}</ref><ref>{{cite journal |last1=Emery |first1=Virginia L. |title=Mud-Brick |journal=UCLA Encyclopedia of Egyptology |date=2009 |volume=1 |issue=1 |url=https://escholarship.org/content/qt7v84d6rh/qt7v84d6rh.pdf}}</ref>\n\nThe 9000 BCE dwellings of [[Jericho]], were constructed from mudbricks,<ref>{{Cite book|last=Tellier|first=Luc-Normand|url=https://books.google.com/books?id=cXuCjDbxC1YC&q=jericho+9000+bc+bricks&pg=PA37|title=Urban World History: An Economic and Geographical Perspective|date=2009|publisher=PUQ|isbn=978-2-7605-2209-1|language=en}}</ref> affixed with mud, as would those at  numerous sites across the [[Levant]] over the following millennia. Well-preserved mudbricks from a site at Tel Tsaf, in the Jordan Valley, have been dated to 5200 BCE,<ref name=":0">{{Cite journal|last1=Rosenberg|first1=Danny|last2=Love|first2=Serena|last3=Hubbard|first3=Emily|last4=Klimscha|first4=Florian|date=2020-01-22|title=7,200 years old constructions and mudbrick technology: The evidence from Tel Tsaf, Jordan Valley, Israel|journal=PLOS ONE|language=en|volume=15|issue=1|pages=e0227288|doi=10.1371/journal.pone.0227288|issn=1932-6203|pmc=6975557|pmid=31968007|bibcode=2020PLoSO..1527288R|doi-access=free}}</ref> though there is no evidence that either site was the first to use the technology. Evidence suggests that the mudbrick composition at Tel Tsaf was stable for at least 500 years, throughout the middle [[Chalcolithic]] period.<ref name="Rosenberg2020"/>\n\nThe [[South Asia]]n inhabitants of [[Mehrgarh]] constructed and lived in mud-brick houses between 7000\u20133300 BC.<ref name="Possehl">Possehl, Gregory L. (1996)</ref> Mud bricks were used at more than 15 reported sites attributed to the 3rd millennium BC in the ancient [[Indus Valley Civilization]]. In the [[Mature Harappan]] phase fired bricks were used.<ref name="Bricks and Urbanism in Indus Valley">[https://www.academia.edu/1285495/Bricks_and_urbanism_in_the_Indus_Valley_rise_and_decline Bricks and urbanism in the Indus Valley rise and decline], bricks in antiquity</ref> \n\nThe [[Mesopotamia]]ns used sun-dried bricks in their city construction; <ref>Mogens Herman Hansen, ''A Comparative Study of Six City-state Cultures'', K\u00f8benhavns universitet Polis centret (2002) Videnskabernes Selskab, 144 pages {{ISBN|87-7876-316-9}}</ref> typically these bricks were flat on the bottom and curved on the top, called plano-convex mud bricks. Some were formed in a square mould and rounded so that the middle was thicker than the ends.  Some walls had a few courses of fired bricks from their bases up to the splash line to extend the life of the building.\n\nIn [[Minoan civilization|Minoan]] [[Crete]], at the [[Knossos]] site, there is [[archaeological]] evidence that sun-dried bricks were used in the [[Neolithic]] period (prior to 3400 BC).<ref>C. Michael Hogan, [http://www.themodernantiquarian.com/site/10854/knossos.html#fieldnotes ''Knossos fieldnotes'', Modern Antiquarian (2007)]</ref>\n\nSun dried mudbrick was the most common construction material employed in [[ancient Egypt]] during pharaonic times and were made in pretty much the same way for millennia. Mud from some locations required sand, chopped straw or other binders such as animal dung to be mixed in with the mud to increase durability and plasticity.<ref name="Morgenstein1998"/> Workers gathered mud from the Nile river and poured it into a pit. Workers then tramped on the mud while straw was added to solidify the mold.{{cn|date=December 2018}} The mudbricks were chemically suitable as fertilizer, leading to the destruction of many ancient Egyptian ruins, such as at [[Edfu]]. A well-preserved site is [[Amarna]].<ref>{{cite book|last=Hawkes|first=Jacquetta|author-link=Jacquetta Hawkes|title=Atlas of Ancient Archaeology|year=1974|publisher=[[McGraw-Hill Education|McGraw-Hill Book Company]]|isbn=0-07-027293-X|page=[https://archive.org/details/atlasofancientar00hawk/page/146 146]|url-access=registration|url=https://archive.org/details/atlasofancientar00hawk/page/146}}</ref> Mudbrick use increased at the time of [[Ancient Rome|Roman]] influence.<ref>Kathryn A. Bard and Steven Blake Shubert, ''Encyclopedia of the Archaeology of Ancient Egypt'', 1999, Routledge, 938 pages  {{ISBN|0-415-18589-0}}</ref>\n\nIn the [[Ancient Greece|Ancient Greek]] world, mudbrick was commonly used for the building of walls, fortifications and citadels, such as the walls of the Citadel of [[Troy]] (Troy II).<ref>[[Richard T. Neer|Neer, Richard. T]]., ''Art & archaeology of the Greek world: a new history, c. 2500-c.150 BCE,'' Second edition, Thames and Hudson, London, 2019, pp.23</ref> These mudbricks were often made with straw or dried vegetable matter.<ref>{{cite book |last1=Birge |first1=Darice Elizabeth |last2=Miller |first2=Stephen Gaylord |last3=Kraynak |first3=Lynn Harriett |last4=Miller |first4=S. G. |title=Excavations at Nemea. |date=1992\u20132018 |publisher=University of California Press |isbn=978-0-520-07027-1 |page=113n345 |url=https://www.google.com/books?id=ojTPxLcWGTwC&pg=PA113 |quote=Adding straw or dried vegetable matter to the clay of mudbricks was a common practice}}</ref>"}},
{"article_title": "Bow drill", "pageid": "140988", "revid": "1030505949", "timestamp": "2021-06-26T10:19:04Z", "history_paths": [["Bow drill --- Introduction ---", "History"]], "categories": ["mechanical hand tools", "primitive technology", "woodworking hand tools", "firelighting using friction"], "heading_tree": {"Bow drill --- Introduction ---": {"History": {}, "Usage": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Bow drill --- Introduction ---|History": "Bow drills with [[jasper|green jasper]] bits were used in [[Mehrgarh]] between the 4th and 5th millennium BC to drill holes into [[lapis lazuli]] and [[carnelian]]. Similar drills were found in other parts of the [[Indus Valley Civilization]] and [[Iran]] one millennium later.<ref name=kulke2004/>"}},
{"article_title": "Comet Hyakutake", "pageid": "141738", "revid": "1062202646", "timestamp": "2021-12-27T00:34:00Z", "history_paths": [["Comet Hyakutake --- Introduction ---"], ["Comet Hyakutake --- Introduction ---", "Discovery"]], "categories": ["non-periodic comets", "science and technology in japan", "astronomical objects discovered in 1996", "great comets"], "heading_tree": {"Comet Hyakutake --- Introduction ---": {"Discovery": {}, "Orbit": {}, "Earth passage": {}, "Perihelion and afterwards": {}, "Scientific results": {"Spacecraft passes through the tail": {}, "Composition": {}, "X-ray emission": {}, "Nucleus size and activity": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Comet Hyakutake --- Introduction ---": "{{Short description|Comet that passed close to Earth in March 1996}}\n{{Infobox planet\n| minorplanet = yes\n| background = #FFE0C2\n| name = C/1996 B2 (Hyakutake)\n| image = Hyakutake Color.jpg\n| image_size = 240\n| caption = The comet on the evening of its closest approach to Earth on 25 March 1996\n| discovery_ref =\n| discoverer = [[Yuji Hyakutake]]\n| discovered = 31 January 1996<ref name="iauc6299">Comet was discovered on 1996 January 30.8 UT (local time: January 31), see [http://www.cbat.eps.harvard.edu/iauc/06200/06299.html IAU Circular No. 6299] {{Webarchive|url=https://web.archive.org/web/20141222230944/http://www.cbat.eps.harvard.edu/iauc/06200/06299.html |date=2014-12-22 }}</ref>\n| mpc_name =\n| alt_names = Great Comet of 1996\n| mp_category =\n| orbit_ref = <ref>{{cite web|url=http://www.eso.org/public/events/astro-evt/hyakutake/eph/comet-hyakutake-eph-may23-bm.txt |title=Comet Hyakutake: Orbital elements and 10-day ephemeris |publisher=European Southern Observatory |url-status=dead |archive-url=https://web.archive.org/web/20090203101107/http://www.eso.org/public/events/astro-evt/hyakutake/eph/comet-hyakutake-eph-may23-bm.txt |archive-date=2009-02-03 }}</ref><ref name=barycenter>{{cite web \n |date=2011-01-30 \n |author=Horizons output \n |author-link=JPL Horizons On-Line Ephemeris System \n |url=http://home.comcast.net/~kpheider/Hyakutake-70kyr.txt \n |title=Barycentric Osculating Orbital Elements for Comet Hyakutake (C/1996 B2) \n |access-date=2011-01-30 \n |archive-url=https://archive.today/20130703113349/http://home.surewest.net/kheider/astro/Hyakutake-70kyr.txt \n |archive-date=July 3, 2013 \n }} ([http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=C/1996+B2 Horizons] {{Webarchive|url=https://web.archive.org/web/20190605225109/https://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=C%2F1996+B2 |date=2019-06-05 }})</ref>\n| epoch = 2450400.5\n| aphelion = ~1320 [[Astronomical Unit|AU]] (inbound)<ref name=barycenter/>{{ref_label|A|a|none}}<br/>~3500 AU (outbound)\n| perihelion = 0.2301987 AU\n| semimajor = 1700 AU (outbound)<ref name=barycenter/>{{ref_label|A|a|none}}\n| eccentricity = 0.9998946\n| period = ~17,000 [[Julian year (astronomy)|yr]] (inbound)<ref name=barycenter/>{{ref_label|A|a|none}}<br/>~72,000 (outbound)\n| inclination = 124.92246\u00b0\n| asc_node = 188.05766\u00b0\n| mean_anomaly =\n| arg_peri = 130.17218\u00b0\n| physical_characteristics =\n| dimensions = {{cvt|4.2|km}}<ref name=jpldata>{{JPL Small Body|name=C/1996 B2}}</ref>\n| sidereal_day = 6 hours\n}}\n\n'''Comet Hyakutake''' ({{IPA-ja|\u00e7ak\u026f\u0325take}}, [[Astronomical naming conventions#Comets|formally designated]] '''C/1996 B2''') is a [[comet]], discovered on 31 January 1996,<ref name="iauc6299"/> that passed very close to Earth in March of that year. It was dubbed the '''Great Comet of 1996'''; its passage near the Earth was one of the closest cometary approaches of the previous 200 years. Hyakutake appeared very bright in the night sky and was widely seen around the world. The comet temporarily upstaged the much anticipated [[Comet Hale\u2013Bopp]], which was approaching the inner [[Solar System]] at the time.\n\nScientific observations of the comet led to several discoveries. Most surprising to cometary scientists was the first discovery of [[X-ray]] emission from a comet, believed to have been caused by ionised [[solar wind]] particles interacting with neutral [[atom]]s in the [[coma (cometary)|coma]] of the comet. The [[Ulysses probe|''Ulysses'' spacecraft]] unexpectedly crossed the comet's tail at a distance of more than {{convert|500|e6km|AU e6mi|abbr=unit}} from the [[comet nucleus|nucleus]], showing that Hyakutake had the longest tail known for a comet.\n\nHyakutake is a [[Comet#Orbital characteristics|long-period comet]]. Before its most recent passage through the Solar System, its orbital period was about 17,000 years,<ref name=barycenter/><ref name="jbaa"/> but the [[gravitational]] [[Perturbation (astronomy)|perturbation]] of the [[giant planet]]s has increased this period to 70,000 years.<ref name=barycenter/><ref name="jbaa"/>\n\n The comet was discovered on 30 January 1996,<ref name="iauc6299"/> by [[Yuji Hyakutake]], an [[amateur]] [[astronomer]] from southern Japan.<ref>{{cite web| publisher=[[NASA]]| access-date=9 January 2007| title=Comet C/1996 B2 Hyakutake| url=http://www2.jpl.nasa.gov/comet/hyakutake/index.html| archive-url=https://web.archive.org/web/20110106160112/http://www2.jpl.nasa.gov/comet/hyakutake/index.html| archive-date=6 January 2011| url-status=live}}</ref> He had been searching for comets for years and had moved to [[Kagoshima Prefecture]] partly for the dark skies in nearby rural areas. He was using a powerful set of [[binoculars]] with {{cvt|150|mm|0}} [[objective lens]]es to scan the skies on the night of the discovery.<ref>For a photo of Hyakutake and his binocular, see [http://www.skyandtelescope.com/observing/objects/comets/3304291.html?page=1&c=y How Yuji Hyakutake Found His Comet] {{Webarchive|url=https://web.archive.org/web/20090203005926/http://www.skyandtelescope.com/observing/objects/comets/3304291.html?page=1&c=y |date=2009-02-03 }} (Sky&Telescope. Retrieved on 21 April 2008).</ref>\n\nThis comet was actually the second Comet Hyakutake; Hyakutake had discovered comet [[C/1995 Y1]] several weeks earlier.<ref>{{cite web| publisher=[[NASA]] |work=Gekkan Tenmon| url=http://www2.jpl.nasa.gov/comet/hyakutake/disc1.html| title=How Comet Hyakutake B2 Was Discovered| access-date=9 January 2007| author=Yuji Hyakutake| date=April 1996| archive-url=https://www.webcitation.org/6149Bh5w3?url=http://www2.jpl.nasa.gov/comet/hyakutake/disc1.html| archive-date=19 August 2011| url-status=live}}</ref> While re-observing his first comet (which never became visible to the [[naked eye]]) and the surrounding patch of sky, Hyakutake was surprised to find another comet in almost the same position as the first had been. Hardly believing a second discovery so soon after the first, Hyakutake reported his observation to the [[National Astronomical Observatory of Japan]] the following morning.<ref>{{cite press release|title=Press Statement by Mr. Yuji Hyakutake Discoverer of Comet Hyakutake|url=http://www2.jpl.nasa.gov/comet/hyakutake/disc2.html|access-date=13 February 2007|author=Yuji Hyakutake|archive-url=https://www.webcitation.org/6E8Cxj8Ra?url=http://www2.jpl.nasa.gov/comet/hyakutake/disc2.html|archive-date=2 February 2013|url-status=live}}</ref> Later that day, the discovery was confirmed by independent observations.{{citation needed|date=January 2019}}\n\nAt the time of its discovery, the comet was shining at [[apparent magnitude|magnitude]] 11.0 and had a coma approximately 2.5 [[arcminute]]s across. It was approximately 2 [[astronomical unit]]s (AU) from the [[Sun]].<ref>{{cite press release| title=Press Information Sheet: Comet C/1996 B2 (Hyakutake)| url=http://www.cfa.harvard.edu/iau/pressinfo/info1996B2.html| access-date=16 October 2007| publisher=Harvard-Smithsonian Center for Astrophysics| date=20 November 1996| archive-url=https://web.archive.org/web/20071121004046/http://www.cfa.harvard.edu/iau/pressinfo/info1996B2.html| archive-date=2007-11-21| url-status=dead}}</ref> Later, a [[precovery]] image of the comet was found on a photograph taken on January 1, when the comet was about 2.4 AU from the Sun and had a magnitude of 13.3.<ref name="jbaa">{{cite journal | author= James, N.D. | title=Comet C/1996 B2 (Hyakutake): The Great Comet of 1996 | journal=Journal of the British Astronomical Association | year=1998 | volume=108 | pages=157 | bibcode = 1998JBAA..108..157J }}</ref>\n\n [[File:Comet Hyakutake inner solar system 1996.png|thumb|320px|left|Comet Hyakutake's trajectory through the inner solar system, with a high inclination, passed closest to the earth in late March 1996, passing over the earth's north pole. It was at perihelion on May 1.]]\n\nWhen the first calculations of the comet's [[orbit]] were made, scientists realized that it was going to pass just 0.1 AU from Earth on 25 March.<ref name="Miller1996">{{cite journal|title=8.35 and 14.35 GHz continuum observations of comet Hyakutake C/1996 B2|journal=Astrophysical Journal Letters| doi=10.1086/310192| volume=467| pages=L37\u2013L40| issue=1| year=1996|author=Minter, Anthony H.|last2=Langston|first2=Glen|bibcode = 1996ApJ...467L..37M |doi-access=free}}</ref> Only four comets in the previous century had passed closer.<ref>{{cite web|url = http://www.eso.org/public/outreach/press-rel/pr-1996/pr-06-96.html|title = Comet Hyakutake to Approach the Earth in Late March 1996|publisher = European Southern Observatory|url-status = dead|archive-url = https://web.archive.org/web/20110804223613/http://www.eso.org/public/news/eso9613/|archive-date = 2011-08-04}}</ref> [[Comet Hale\u2013Bopp]] was already being discussed as a possible "[[great comet]]"; the astronomical community eventually realised that Hyakutake might also become spectacular because of its close approach.\n\nMoreover, Comet Hyakutake's orbit meant that it had last been to the inner [[Solar System]] approximately 17,000 years earlier.<ref name=barycenter/> Because it had probably passed close to the Sun several times before,<ref name="jbaa"/> the approach in 1996 would not be a maiden arrival from the [[Oort cloud]], a place where comets with orbital periods of millions of years come from. Comets entering the inner Solar System for the first time may brighten rapidly before fading as they near the Sun, because a layer of highly volatile material evaporates. This was the case with [[Comet Kohoutek]] in 1973; it was initially touted as potentially spectacular, but only appeared moderately bright. Older comets show a more consistent brightening pattern. Thus, all indications suggested Comet Hyakutake would be bright.{{citation needed|date=January 2019}}\n\nBesides approaching close to Earth, the comet would also be visible throughout the night to [[northern hemisphere]] observers at its closest approach because of its path, passing very close to the [[pole star]]. This would be an unusual occurrence, because most comets are close to the Sun in the sky when the comets are at their brightest, leading to the comets appearing in a sky not completely dark.{{citation needed|date=January 2019}}\n\n [[File:Comet_Hyakutake_skyview_1996.png|thumb|The path of Comet Hyakutake across the sky]]\n\nHyakutake became visible to the naked eye in early March 1996. By mid-March, the comet was still fairly unremarkable, shining at 4th [[Apparent magnitude|magnitude]] with a tail about 5 [[degree (angle)|degrees]] long. As it neared its closest approach to Earth, it rapidly became brighter, and its tail grew in length. By March 24, the comet was one of the brightest objects in the night sky, and its tail stretched 35 degrees. The comet had a notably bluish-green colour.<ref name="jbaa"/>\n\nThe closest approach occurred on 25 March at a distance of {{Convert|0.1|AU|e6km LD|abbr=unit|lk=on}}.<ref name=jpldata/> Hyakutake was moving so rapidly across the night sky that its movement could be detected against the stars in just a few minutes; it covered the [[diameter]] of a [[full moon]] (half a degree) every 30 minutes. Observers estimated its magnitude as around 0, and tail lengths of up to 80 degrees were reported.<ref name="jbaa"/> Its coma, now close to the [[zenith]] for observers at mid-northern [[latitude]]s, appeared approximately 1.5 to 2 degrees across, roughly four times the diameter of the full moon.<ref name="jbaa"/> Even to the naked eye, the comet's head appeared distinctly green, due to strong emissions from [[diatomic carbon]] (C<sub>2</sub>).{{citation needed|date=January 2019}}\n\nBecause Hyakutake was at its brightest for only a few days, it did not have time to permeate the public imagination in the way that [[Comet Hale\u2013Bopp]] did the following year. Many European observers in particular did not see the comet at its peak because of unfavourable weather conditions.<ref name="jbaa"/>\n\n After its close approach to the Earth, the comet faded to about 2nd magnitude. It reached [[perihelion]] on 1 May 1996, brightening again and exhibiting a dust tail in addition to the gas tail seen as it passed the Earth. By this time, however, it was close to the Sun and was not seen as easily. It was observed passing perihelion by the [[Solar and Heliospheric Observatory|''SOHO'']] Sun-observing [[satellite]], which also recorded a large [[coronal mass ejection]] being formed at the same time. Its distance from the Sun at perihelion was 0.23 AU, well inside the orbit of [[Mercury (planet)|Mercury]].<ref>{{cite press release| url=http://www.eso.org/outreach/press-rel/pr-1996/pr-06-96.html| title=Comet Hyakutake to Approach the Earth in Late March 1996| publisher=European Southern Observatory| access-date=20 February 2007| date=13 July 1996| url-status=dead| archive-url=https://web.archive.org/web/20070208073005/http://www.eso.org/outreach/press-rel/pr-1996/pr-06-96.html| archive-date=8 February 2007}}</ref>\n\nAfter its perihelion passage, Hyakutake faded rapidly and was lost to naked-eye visibility by the end of May. Its orbital path carried it rapidly into the southern skies, but following perihelion it became much less monitored. The last known observation of the comet took place on November 2.<ref>{{Cite web |url=http://www.oaa.gr.jp/~oaacs/nk/nk838.htm |title=Nakano Note 838 |access-date=2008-05-12 |archive-url=https://www.webcitation.org/6149E95Rp?url=http://www.oaa.gr.jp/~oaacs/nk/nk838.htm |archive-date=2011-08-19 |url-status=live }}</ref>\n\nHyakutake had passed through the inner Solar System approximately 17,000 years ago; gravitational interactions with the [[gas giants]] during its 1996 passage stretched its orbit greatly, and [[Barycentric coordinates (astronomy)|barycentric fits]] to the comet's orbit predict it will not return to the inner [[Solar System]] again for approximately 70,000<ref name=barycenter/><ref name="jbaa"/>{{ref_label|A|a|none}} years.\n\n \n [[File:Animation of Ulysses trajectory.gif|thumb|right|Animation of ''Ulysses''{{'}} trajectory from 6 October 1990 to 29 June 2009<br/>{{legend2|magenta|''Ulysses''}}{{\u00b7}}{{legend2|Royalblue|[[Earth]]}}{{\u00b7}}{{legend2|Gold|[[Jupiter]]}}{{\u00b7}}{{legend2|Cyan|[[C/2006 P1]]}}{{\u00b7}}{{legend2|Lime|C/1996 B2}}{{\u00b7}}{{legend2|OrangeRed|[[C/1999 T1]]}}]]\nThe [[Ulysses (spacecraft)|''Ulysses'' spacecraft]] made an unexpected pass through the tail of the comet on 1 May 1996.<ref>{{cite news |publisher=PhysicsWeb |title=Comet Hyakutake makes a mark on ''Ulysses'' |date=6 April 2000 |url=https://physicsworld.com/a/comet-hyakutake-makes-a-mark-on-ulysses/ |access-date=9 November 2020 |archive-url=https://web.archive.org/web/20201109190833/https://physicsworld.com/a/comet-hyakutake-makes-a-mark-on-ulysses/ |archive-date=9 November 2020 |url-status=live }}</ref> Evidence of the encounter was not noticed until 1998. Astronomers analysing old data found that ''Ulysses''{{'}} instruments had detected a large drop in the number of [[proton]]s passing, as well as a change in the direction and strength of the local [[magnetic field]]. This implied that the spacecraft had crossed the 'wake' of an object, most likely a comet; the object responsible was not immediately identified.{{citation needed|date=January 2019}}\n\nIn 2000, two teams independently analyzed the same event. The [[magnetometer]] team realized that the changes in the direction of the magnetic field mentioned above agreed with the "draping" pattern expected in a comet's ion, or plasma tail. The magnetometer team looked for likely suspects. No known comets were located near the satellite, but looking further afield, they found that Hyakutake, {{convert|500|e6km|AU|abbr=unit}} away, had crossed ''Ulysses''{{'}} orbital plane on 23 April 1996. The [[solar wind]] had a velocity at the time of about {{cvt|750|km/s}}, at which speed it would have taken eight days for the tail to be carried out to where the spacecraft was situated at 3.73 AU, approximately 45 degrees out of the [[ecliptic]] plane. The orientation of the ion tail inferred from the magnetic field measurements agreed with the source lying in Comet Hyakutake's orbital plane.<ref name="nature">{{cite journal |author1=Jones, G. H. |author2=Balogh, A. |author3=Horbury, T. S. |title=Identification of comet Hyakutake's extremely long ion tail from magnetic field signatures |journal=Nature |year=2000 |volume=404 |pages=574\u2013576 |bibcode=2000Natur.404..574J |doi=10.1038/35007011 |pmid=10766233 |issue=6778|s2cid=4418311 }}</ref>\n\nThe other team, working on data from the spacecraft's ion composition spectrometer, discovered a sudden large spike in detected levels of [[ion]]ised particles at the same time. The relative abundances of chemical elements detected indicated that the object responsible was definitely a comet.<ref name="nature2">{{cite journal |author=Gloeckler |title=Interception of comet Hyakutake's ion tail at a distance of 500 million kilometres |journal=Nature |year=2000 |volume=404 |pages=576\u2013578 |bibcode=2000Natur.404..576G |doi=10.1038/35007015 |pmid=10766234 |issue=6778 |author2=G. |author3=Geiss |author4=J. |author5=Schwadron |author6=N.A. |display-authors=6 |last7=Von Steiger |first7=R. |last8=Balsiger |first8=H. |last9=Wilken |first9=B.|hdl=2027.42/62756 |s2cid=4420901 |url=https://deepblue.lib.umich.edu/bitstream/2027.42/62756/1/404576a0.pdf |hdl-access=free }}</ref>\n\nBased on the ''Ulysses'' encounter, the comet's tail is known to have been at least 570 million km (360 million miles; 3.8 AU) long. This is almost twice as long as the previous longest-known cometary tail, that of the [[Great Comet of 1843]], which was 2.2 AU long.{{citation needed|date=January 2019}}\n\n Terrestrial observers found [[ethane]] and [[methane]] in the comet, the first time either of these gases had been detected in a comet. Chemical analysis showed that the abundances of ethane and methane were roughly equal, which may imply that its ices formed in interstellar space, away from the Sun, which would have evaporated these volatile molecules. Hyakutake's ices must have formed at temperatures of 20 [[Kelvin|K]] or less, indicating that it probably formed in a denser-than-average interstellar cloud.<ref name="science">{{cite journal |author1=Mumma, M.J. |author2=Disanti, M.A. |author3=dello Russo, N. |author4=Fomenkova, M. |author5=Magee-Sauer, K. |author6=Kaminski, C.D. |author7=Xie, D.X. |title=Detection of Abundant Ethane and Methane, Along with Carbon Monoxide and Water, in Comet C/1996 B2 Hyakutake: Evidence for Interstellar Origin |journal=Science |year=1996 |volume=272 |pages=1310\u20131314 |bibcode=1996Sci...272.1310M |doi=10.1126/science.272.5266.1310 |pmid=8650540 |issue=5266|s2cid=27362518 }}</ref>\n\nThe amount of [[deuterium]] in the comet's water ices was determined through [[astronomical spectroscopy|spectroscopic]] observations.<ref name="icarus">{{cite journal |author=Bockelee-Morvan, D. |author2=Gautier |title=Deuterated Water in Comet C/1996 B2 (Hyakutake) and Its Implications for the Origin of Comets |journal=Icarus |year=1998 |volume=133 |issue=1 |pages=147\u2013162 |bibcode=1998Icar..133..147B |doi=10.1006/icar.1998.5916|hdl=2060/19980035143 |hdl-access=free }}</ref> It was found that the ratio of deuterium to [[hydrogen]] (known as the D/H ratio) was about 3{{E|\u22124}}, which compares to a value in Earth's oceans of about 1.5{{E|\u22124}}. It has been proposed that cometary collisions with Earth might have supplied a large proportion of the water in the oceans, but the high D\u2013H ratio measured in Hyakutake and other comets such as Hale\u2013Bopp and [[Halley's Comet]] have caused problems for this theory.{{citation needed|date=January 2019}}\n\n [[File:X-rays from Hyakutake.jpg|thumb|right|150px|[[X-ray]] emission from Hyakutake, as seen by the [[ROSAT]] satellite]]\n\nOne of the great surprises of Hyakutake's passage through the inner Solar System was the discovery that it was emitting [[X-rays]], with observations made using the ''[[ROSAT]]'' satellite revealing very strong X-ray emission.<ref name="science2">{{cite journal |author=Glanz, J |title=Comet Hyakutake Blazes in X-rays |journal=Science |year=1996 |volume=272 |pages=194\u20130 |bibcode=1996Sci...272..194G |doi=10.1126/science.272.5259.194 |issue=5259|s2cid=120173459 }}</ref> This was the first time a comet had been seen to do so, but astronomers soon found that almost every comet they looked at was emitting X-rays. The emission from Hyakutake was brightest in a crescent shape surrounding the nucleus with the ends of the crescent pointing away from the Sun.{{citation needed|date=January 2019}}\n\nThe cause of the X-ray emission is thought to be a combination of two mechanisms. Interactions between energetic solar wind particles and cometary material evaporating from the nucleus is likely to contribute significantly to this effect.<ref>{{cite journal |journal=Science |title=Discovery of X-ray and Extreme Ultraviolet Emission from Comet C/Hyakutake 1996 B2 |author1=C. M. Lisse |author2=K. Dennerl |author3=J. Englhauser |author4=M. Harden |author5=F. E. Marshall |author6=M. J. Mumma |author7=R. Petre |author8=J. P. Pye |author9=M. J. Ricketts |author10=J. Schmitt |author11=J. Tr\u00fcmper |author12=R. G. West |year=1996 |volume=274 |issue=5285 |pages=205\u2013209 |doi=10.1126/science.274.5285.205 |bibcode=1996Sci...274..205L|s2cid=122700701 |url=https://zenodo.org/record/1231082 }}</ref> Reflection of solar X-rays is seen in other Solar System objects such as the [[Moon]], but a simple calculation assuming even the highest X-ray reflectivity possible per molecule or dust grain is not able to explain the majority of the observed flux from Hyakutake, as the comet's atmosphere is very tenuous and diffuse. Observations of comet [[C/1999 S4 (LINEAR)]] with the [[Chandra X-ray Observatory|''Chandra'' satellite]] in 2000 determined that X-rays observed from that comet were produced predominantly by charge exchange collisions between highly charged [[carbon]], [[oxygen]] and [[nitrogen]] minor ions in the solar wind, and neutral water, oxygen and hydrogen in the comet's coma.{{citation needed|date=January 2019}}\n\n [[File:Comet Hyakutake from Hubble.jpg|thumb|left|Comet Hyakutake captured by the [[Hubble Space Telescope]] on 4 April 1996, with an [[infrared filter]]]]\n\n[[File:Nucleus of Hyakutake.png|thumb|right|250px|The region around the [[comet nucleus|nucleus]] of Comet Hyakutake, as seen by the [[Hubble Space Telescope]]. Some fragments can be seen breaking off.]]\n\nRadar results from the [[Arecibo Observatory]] indicated that the [[comet nucleus]] was about {{cvt|4.8|km|0}} across, and surrounded by a flurry of pebble-sized particles ejected at a few metres per second. This size measurement corresponded well with indirect estimates using [[infrared]] emission and radio observations.<ref name="ajl">{{cite journal |author1=Sarmecanic, J. |author2=Fomenkova, M. |author3=Jones, B. |author4=Lavezzi, T. |title=Constraints on the Nucleus and Dust Properties from Mid-Infrared Imaging of Comet Hyakutake |journal=Astrophysical Journal Letters |year=1997 |volume=483 |issue=1 |pages=L69\u2013L72 |bibcode=1997ApJ...483L..69S |doi=10.1086/310726|pmid=11541247 }}</ref><ref name="icarus2">{{cite journal |author=Lisse |author2=C.M. |title=The Nucleus of Comet Hyakutake (C/1996 B2) |journal=Icarus |year=1999 |volume=140 |issue=1 |pages=189\u2013204 |bibcode=1999Icar..140..189L |doi=10.1006/icar.1999.6131}}</ref>\n\nThe small size of the nucleus ([[Halley's Comet]] is about {{cvt|15|km}} across, while Comet Hale\u2013Bopp was about {{cvt|60|km}} across) implies that Hyakutake must have been very active to become as bright as it did. Most comets undergo outgassing from a small proportion of their surface, but most or all of Hyakutake's surface seemed to have been active. The dust production rate was estimated to be about 2{{E|3}} kg/s at the beginning of March, rising to 3{{E|4}} kg/s as the comet approached perihelion. During the same period, dust ejection velocities increased from 50 m/s to 500 m/s.<ref name="aa">{{cite journal |author=Fulle, M. |author2=Mikuz, H. |author3=S. Bosio |name-list-style=amp |title=Dust environment of Comet Hyakutake 1996 B2 |journal=Astronomy and Astrophysics |year=1997 |volume=324 |pages=1197 |bibcode=1997A&A...324.1197F}}</ref><ref name="aj">{{cite journal |author1=Jewitt, D.C. |author2=H.E. Matthews |title=Submillimeter Continuum Observations of Comet Hyakutake (1996 B2) |journal=Astronomical Journal |year=1997 |volume=113 |pages=1145 |bibcode=1997AJ....113.1145J |doi=10.1086/118333}}</ref>\n\nObservations of material being ejected from the nucleus allowed astronomers to establish its rotation period. As the comet passed the Earth, a large puff or blob of material was observed being ejected in the sunward direction every 6.23 hours. A second smaller ejection with the same period confirmed this as the rotation period of the nucleus.<ref name="icarus3">{{cite journal |author=Schleicher, D.G. |author2=Millis, R.L. |author3=Osip, D.J. |author4=S.M. Lederer |name-list-style=amp |title=Activity and the Rotation Period of Comet Hyakutake (1996 B2) |journal=Icarus |year=1998 |volume=131 |pages=233\u2013244 |bibcode=1998Icar..131..233S |doi=10.1006/icar.1997.5881 |issue=2}}</ref>\n\n * [[Lists of comets]]\n\n {{Refbegin}}\n<ol type="a">\n\n<li>{{Note_label|A|a|none}} Solution using the Solar System [[Center of mass#Barycenter in astrophysics and astronomy|Barycenter]]. For objects at such high eccentricity, the Sun's [[Barycentric coordinates (astronomy)|barycentric coordinates]] are more stable than heliocentric coordinates.</li>\n\n</ol>\n{{Refend}}\n\n {{Reflist|colwidth=30em}}\n\n {{Commons category}}\n* [http://www.jpl.nasa.gov/comet/hyakutake/ JPL Comet Hyakutake home page]\n* [https://web.archive.org/web/20080906174837/http://ssd.jpl.nasa.gov/data/ELEMENTS.COMET JPL DASTCOM Cometary Orbital Elements]\n* [http://www.cometography.com/lcomets/1996b2.html Cometography.com: Comet Hyakutake]\n* {{APOD |date=14 March 1996 |title=Diagram of Comet Hyakutake's orbit}}\n* {{JPL Small Body|name=C/1996 B2}}\n\n{{Comets}}\n{{Portal bar|Astronomy|Stars|Spaceflight|Outer space|Solar System}}\n{{Authority control}}\n{{Featured article}}\n\n{{DEFAULTSORT:Hyakutake, 1996 B2}}", "Comet Hyakutake --- Introduction ---|Discovery": "The comet was discovered on 30 January 1996,<ref name="iauc6299"/> by [[Yuji Hyakutake]], an [[amateur]] [[astronomer]] from southern Japan.<ref>{{cite web| publisher=[[NASA]]| access-date=9 January 2007| title=Comet C/1996 B2 Hyakutake| url=http://www2.jpl.nasa.gov/comet/hyakutake/index.html| archive-url=https://web.archive.org/web/20110106160112/http://www2.jpl.nasa.gov/comet/hyakutake/index.html| archive-date=6 January 2011| url-status=live}}</ref> He had been searching for comets for years and had moved to [[Kagoshima Prefecture]] partly for the dark skies in nearby rural areas. He was using a powerful set of [[binoculars]] with {{cvt|150|mm|0}} [[objective lens]]es to scan the skies on the night of the discovery.<ref>For a photo of Hyakutake and his binocular, see [http://www.skyandtelescope.com/observing/objects/comets/3304291.html?page=1&c=y How Yuji Hyakutake Found His Comet] {{Webarchive|url=https://web.archive.org/web/20090203005926/http://www.skyandtelescope.com/observing/objects/comets/3304291.html?page=1&c=y |date=2009-02-03 }} (Sky&Telescope. Retrieved on 21 April 2008).</ref>\n\nThis comet was actually the second Comet Hyakutake; Hyakutake had discovered comet [[C/1995 Y1]] several weeks earlier.<ref>{{cite web| publisher=[[NASA]] |work=Gekkan Tenmon| url=http://www2.jpl.nasa.gov/comet/hyakutake/disc1.html| title=How Comet Hyakutake B2 Was Discovered| access-date=9 January 2007| author=Yuji Hyakutake| date=April 1996| archive-url=https://www.webcitation.org/6149Bh5w3?url=http://www2.jpl.nasa.gov/comet/hyakutake/disc1.html| archive-date=19 August 2011| url-status=live}}</ref> While re-observing his first comet (which never became visible to the [[naked eye]]) and the surrounding patch of sky, Hyakutake was surprised to find another comet in almost the same position as the first had been. Hardly believing a second discovery so soon after the first, Hyakutake reported his observation to the [[National Astronomical Observatory of Japan]] the following morning.<ref>{{cite press release|title=Press Statement by Mr. Yuji Hyakutake Discoverer of Comet Hyakutake|url=http://www2.jpl.nasa.gov/comet/hyakutake/disc2.html|access-date=13 February 2007|author=Yuji Hyakutake|archive-url=https://www.webcitation.org/6E8Cxj8Ra?url=http://www2.jpl.nasa.gov/comet/hyakutake/disc2.html|archive-date=2 February 2013|url-status=live}}</ref> Later that day, the discovery was confirmed by independent observations.{{citation needed|date=January 2019}}\n\nAt the time of its discovery, the comet was shining at [[apparent magnitude|magnitude]] 11.0 and had a coma approximately 2.5 [[arcminute]]s across. It was approximately 2 [[astronomical unit]]s (AU) from the [[Sun]].<ref>{{cite press release| title=Press Information Sheet: Comet C/1996 B2 (Hyakutake)| url=http://www.cfa.harvard.edu/iau/pressinfo/info1996B2.html| access-date=16 October 2007| publisher=Harvard-Smithsonian Center for Astrophysics| date=20 November 1996| archive-url=https://web.archive.org/web/20071121004046/http://www.cfa.harvard.edu/iau/pressinfo/info1996B2.html| archive-date=2007-11-21| url-status=dead}}</ref> Later, a [[precovery]] image of the comet was found on a photograph taken on January 1, when the comet was about 2.4 AU from the Sun and had a magnitude of 13.3.<ref name="jbaa">{{cite journal | author= James, N.D. | title=Comet C/1996 B2 (Hyakutake): The Great Comet of 1996 | journal=Journal of the British Astronomical Association | year=1998 | volume=108 | pages=157 | bibcode = 1998JBAA..108..157J }}</ref>"}},
{"article_title": "Material requirements planning", "pageid": "141906", "revid": "1054157374", "timestamp": "2021-11-08T11:46:47Z", "history_paths": [["Material requirements planning --- Introduction ---", "History"]], "categories": ["information technology management", "computer-aided engineering", "enterprise resource planning terminology", "business terms", "production planning", "production economics", "supply chain management"], "heading_tree": {"Material requirements planning --- Introduction ---": {"History": {}, "The scope of MRP in manufacturing": {"Dependent demand vs independent demand": {}, "Data": {}, "Outputs": {}, "Methods to find order quantities": {}, "Mathematical formulation": {}}, "Problems with MRP systems": {"Solutions to data integrity issues": {}}, "Demand Driven MRP": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Material requirements planning --- Introduction ---|History": "Prior to MRP, and before computers dominated industry, [[Reorder point|reorder point (ROP)]]/reorder-quantity (ROQ) type methods like [[Economic order quantity|EOQ (economic order quantity)]] had been used in manufacturing and inventory management.<ref>Uday Karmarkar, Getting Control of Just-in-Time, Harvard Business Review 1989</ref>\n\nMRP was computerized by the aero engine makers Rolls Royce and General Electric in the early 1950s but not commercialized by them. It was then 'reinvented' to supply the [[Polaris (UK nuclear programme)|Polaris program]] and then, in 1964, as a response to the [[Toyota Production System|Toyota Manufacturing Program]], [[Joseph Orlicky]] developed material requirements planning (MRP). The first company to use MRP was [[Black & Decker]] in 1964, with Dick Alban as project leader. Orlicky's 1975 book ''Material Requirements Planning'' has the subtitle ''The New Way of Life in Production and Inventory Management''.<ref>Joseph Orlicky, Materials Requirement Planning, McGraw-Hill 1975</ref> By 1975, MRP was implemented in 700 companies. This number had grown to about 8,000 by 1981.\n\nIn 1983, [[Oliver Wight]] developed MRP into [[manufacturing resource planning]] (MRP II).<ref>WJ Hopp, ML Spearman ''Commissioned Paper To Pull or Not to Pull: What Is the Question?'' Manufacturing & Service Operations Management, 2004</ref>  In the 1980s, Joe Orlicky's MRP evolved into Oliver Wight's manufacturing resource planning (MRP II) which brings master scheduling, rough-cut capacity planning, [[capacity planning|capacity requirements planning]], S&OP in 1983 and other concepts to classical MRP. By 1989, about one third of the [[software industry]] was MRP II software sold to American industry ($1.2 billion worth of software).<ref>IE. 1991. Competition in manufacturing leads to MRP II. 23 (July) 10-13.</ref>"}},
{"article_title": "Stone tool", "pageid": "142839", "revid": "1062717838", "timestamp": "2021-12-30T03:12:39Z", "history_paths": [["Stone tool --- Introduction ---", "Evolution"]], "categories": ["lithics", "tools", "archaeological artefact types", "primitive technology", "stone objects"], "heading_tree": {"Stone tool --- Introduction ---": {"Evolution": {"Pre-Mode I": {}, "Mode I: The Oldowan Industry": {}, "Mode II: The Acheulean Industry": {}, "Mode III: The Mousterian Industry": {}, "Mode IV: The Aurignacian Industry": {}, "Mode V: The Microlithic Industries": {}, "Neolithic industries": {}}, "Modern uses": {}, "Tool stone": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Stone tool --- Introduction ---|Evolution": "[[File:National park stone tools.jpg|thumb|upright=1.25|A selection of [[prehistoric]] stone tools]]\n\nArchaeologists classify stone tools into [[Industry (archaeology)|industries]] (also known as complexes or technocomplexes<ref name="Clarke 1978">{{Cite book|title=Analytical Archaeology|last=Clarke|first=David|publisher=Columbia University Press|year=1978|isbn=0231046308|edition=2nd|location=New York, NY|pages=372\u2013373}}</ref>) that share distinctive technological or morphological characteristics.<ref>{{cite book |doi=10.1007/978-4-431-54511-8_4 |chapter=Issues of Chronological and Geographical Distributions of Middle and Upper Palaeolithic Cultural Variability in the Levant and Implications for the Learning Behavior of Neanderthals and Homo sapiens |title=Dynamics of Learning in Neanderthals and Modern Humans Volume 1 |year=2013 |last1=Kadowaki |first1=Seiji |pages=59\u201391 |isbn=978-4-431-54510-1 }}</ref>\n\nIn 1969 in the 2nd edition of ''World Prehistory'', [[Grahame Clark]] proposed an evolutionary progression of [[flint-knapping]] in which the "dominant lithic technologies" occurred in a fixed sequence from Mode 1 through Mode 5.<ref>{{cite book | first=Grahame |last=Clarke |title=World Prehistory: a New Outline | year=1969 |edition=2 | publisher=Cambridge University Press | location=Cambridge |page=31}}</ref> He assigned to them relative dates: Modes 1 and 2 to the Lower [[Palaeolithic]], 3 to the [[Middle Palaeolithic]], 4 to the [[Upper Paleolithic|Advanced]] and 5 to the [[Mesolithic]]. They were not to be conceived, however, as either universal\u2014that is, they did not account for all [[lithic technology]]; or as synchronous\u2014they were not in effect in different regions simultaneously. Mode 1, for example, was in use in [[Europe]] long after it had been replaced by Mode 2 in [[Africa]].\n\nClark's scheme was adopted enthusiastically by the archaeological community. One of its advantages was the simplicity of terminology; for example, the Mode 1 / Mode 2 Transition. The transitions are currently of greatest interest. Consequently, in the literature the stone tools used in the period of the [[Palaeolithic]] are divided into four "modes", each of which designates a different form of complexity, and which in most cases followed a rough [[chronological]] order.\n\n ;Kenya\nStone tools found from 2011 to 2014 at [[Lake Turkana]] in [[Kenya]], are dated to be 3.3 million years old, and predate the genus ''Homo'' by about one million years.<ref>{{cite journal |last1=Harmand |first1=Sonia |last2=Lewis |first2=Jason E. |last3=Feibel |first3=Craig S. |last4=Lepre |first4=Christopher J. |last5=Prat |first5=Sandrine |last6=Lenoble |first6=Arnaud |last7=Bo\u00ebs |first7=Xavier |last8=Quinn |first8=Rhonda L. |last9=Brenet |first9=Michel |last10=Arroyo |first10=Adrian |last11=Taylor |first11=Nicholas |last12=Cl\u00e9ment |first12=Sophie |last13=Daver |first13=Guillaume |last14=Brugal |first14=Jean-Philip |last15=Leakey |first15=Louise |last16=Mortlock |first16=Richard A. |last17=Wright |first17=James D. |last18=Lokorodi |first18=Sammy |last19=Kirwa |first19=Christopher |last20=Kent |first20=Dennis V. |last21=Roche |first21=H\u00e9l\u00e8ne |title=3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya |journal=Nature |date=20 May 2015 |volume=521 |issue=7552 |pages=310\u2013315 |doi=10.1038/nature14464 |pmid=25993961 |bibcode=2015Natur.521..310H |s2cid=1207285 }}</ref><ref>{{cite journal |last1=Foley |first1=R. A. |last2=Miraz\u00f3n Lahr |first2=M. |title=The evolution of the diversity of cultures |journal=Philosophical Transactions of the Royal Society B: Biological Sciences |date=12 April 2011 |volume=366 |issue=1567 |pages=1080\u20131089 |doi=10.1098/rstb.2010.0370 |pmid=21357230 |pmc=3049104 }}</ref> The oldest known ''Homo'' fossil is about 2.4-2.3 million years old compared to the 3.3 million year old stone tools.<ref name='Morelle'>{{cite news |last=Morelle |first=Rebecca |url=https://www.bbc.com/news/science-environment-32804177 |title=Oldest stone tools pre-date earliest humans |work=BBC News |date=20 May 2015 |access-date=2016-01-03 }}</ref>  The stone tools may have been made by ''[[Australopithecus afarensis]]'', the species whose best fossil example is [[Lucy (Australopithecus)|Lucy]], which inhabited East Africa at the same time as the date of the oldest stone tools, or by [[Kenyanthropus|''Kenyanthropus platyops'']] (a 3.2 to 3.5-million-year-old [[Pliocene]] hominin fossil discovered in 1999).<ref>{{cite news |last1=Drake |first1=Nadia |title=Wrong Turn Leads to Discovery of Oldest Stone Tools |url=https://www.nationalgeographic.com/news/2015/05/150520-oldest-stone-tools-discovery-harmand-archaeology/ |work=National Geographic News |date=20 May 2015 }}</ref><ref>{{cite journal |last1=Harmand |first1=Sonia |last2=Lewis |first2=Jason E. |last3=Feibel |first3=Craig S. |last4=Lepre |first4=Christopher J. |last5=Prat |first5=Sandrine |last6=Lenoble |first6=Arnaud |last7=Bo\u00ebs |first7=Xavier |last8=Quinn |first8=Rhonda L. |last9=Brenet |first9=Michel |last10=Arroyo |first10=Adrian |last11=Taylor |first11=Nicholas |last12=Cl\u00e9ment |first12=Sophie |last13=Daver |first13=Guillaume |last14=Brugal |first14=Jean-Philip |last15=Leakey |first15=Louise |last16=Mortlock |first16=Richard A. |last17=Wright |first17=James D. |last18=Lokorodi |first18=Sammy |last19=Kirwa |first19=Christopher |last20=Kent |first20=Dennis V. |last21=Roche |first21=H\u00e9l\u00e8ne |title=3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya |journal=Nature |date=20 May 2015 |volume=521 |issue=7552 |pages=310\u2013315 |doi=10.1038/nature14464 |pmid=25993961 |bibcode=2015Natur.521..310H |s2cid=1207285 }}</ref><ref>{{cite news |last1=Thompson |first1=Helen |title=The Oldest Stone Tools Yet Discovered Are Unearthed in Kenya |url=https://www.smithsonianmag.com/science-nature/oldest-known-stone-tools-unearthed-kenya-180955341/ |work=Smithsonian Magazine |date=May 20, 2015 }}</ref><ref>{{cite news |last1=Wilford |first1=John Noble |title=Stone Tools From Kenya Are Oldest Yet Discovered |url=https://www.nytimes.com/2015/05/21/science/stone-tools-from-kenya-are-oldest-yet-discovered.html |work=The New York Times |date=20 May 2015 }}</ref><ref>{{cite web |title=Oldest Known Stone Tools Discovered: 3.3 Million Years Old |url=https://video.nationalgeographic.com/video/news/0000014d-720b-d248-a94f-7b8bdb7a0000 |date=May 20, 2015 }}</ref> Dating of the tools was by dating volcanic ash layers in which the tools were found and dating the magnetic signature (pointing north or south due to reversal of the magnetic poles)  of the rock at the site.<ref>{{cite web |last1=Zastrow |first1=Mark |title=How a disparate team found the world's oldest stone tools |url=https://www.natureindex.com/news-blog/how-a-disparate-team-found-the-worlds-oldest-tools |website=Nature Index |date=1 April 2016 }}</ref>\n\n;Ethiopia\nGrooved, cut and fractured animal bone fossils, made by using stone tools, were found in [[Dikika]], [[Ethiopia]] near (200 yards) the remains of [[Selam (Australopithecus)|Selam]], a young ''[[Australopithecus afarensis]]'' girl who lived about 3.3 million years ago.<ref>{{cite journal |last1=McPherron |first1=Shannon P. |last2=Alemseged |first2=Zeresenay |last3=Marean |first3=Curtis W. |last4=Wynn |first4=Jonathan G. |last5=Reed |first5=Denn\u00e9 |last6=Geraads |first6=Denis |last7=Bobe |first7=Ren\u00e9 |last8=B\u00e9arat |first8=Hamdallah A. |title=Evidence for stone-tool-assisted consumption of animal tissues before 3.39 million years ago at Dikika, Ethiopia |journal=Nature |date=August 2010 |volume=466 |issue=7308 |pages=857\u2013860 |doi=10.1038/nature09248 |pmid=20703305 |bibcode=2010Natur.466..857M |s2cid=4356816 |lay-url=https://www.sciencedaily.com/releases/2010/08/100811135039.htm |lay-source=ScienceDaily |lay-date=August 11, 2010 }}</ref>\n\n {{Main|Oldowan}}\n[[File:Chopping tool.gif|thumb|upright=1.25|A typical Oldowan simple chopping-tool. This example is from the Duero Valley, [[Valladolid]].]]\n{{Commons category|Oldowan}}\nThe earliest stone tools in the life span of the genus ''[[Homo]]'' are [[Oldowan|Mode 1]] tools,<ref>Clarke's "chopper tools and flakes."</ref> and come from what has been termed the [[Oldowan Industry]], named after the type of site (many sites, actually) found in [[Olduvai Gorge]], [[Tanzania]], where they were discovered in large quantities. Oldowan tools were characterised by their simple construction, predominantly using [[lithic core|core]] forms. These cores were river pebbles, or rocks similar to them, that had been struck by a spherical [[hammerstone]] to cause [[conchoidal fracture]]s removing flakes from one surface, creating an edge and often a sharp tip. The blunt end is the proximal surface; the sharp, the distal. Oldowan is a percussion technology. Grasping the proximal surface, the hominid brought the distal surface down hard on an object he wished to detach or shatter, such as a bone or tuber.{{fact|date=May 2020}}\n\nThe earliest known Oldowan tools yet found date from 2.6 million years ago, during the [[Lower Palaeolithic]] period, and have been uncovered at [[Gona, Ethiopia|Gona]] in [[Ethiopia]].<ref>{{cite journal | author=Semaw, S. |author2=M. J. Rogers |author3=J. Quade |author4=P. R. Renne |author5=R. F. Butler |author6=M. Dom\u00ednguez-Rodrigo |author7=D. Stout |author8=W. S. Hart |author9=T. Pickering |author10= S. W. Simpson  | year=2003 |title=2.6-Million-year-old stone tools and associated bones from OGS-6 and OGS-7, Gona, Afar, Ethiopia | journal=Journal of Human Evolution |volume=45 |issue=2 |pages=169\u2013177 | doi=10.1016/S0047-2484(03)00093-9 | pmid=14529651}}</ref> After this date, the Oldowan Industry subsequently spread throughout much of Africa, although archaeologists are currently unsure which [[Hominan]] species first developed them, with some speculating that it was ''[[Australopithecus garhi]]'', and others believing that it was in fact ''[[Homo habilis]]''.<ref>{{cite book |last1=Toth |first1=Nicholas |last2=Schick |first2=Kathy |chapter=African Origins |pages=46\u201383 |chapter-url=https://archive.org/details/humanpastworldpr0000unse/page/48 |editor1-last=Scarre |editor1-first=Christopher |title=The Human Past: World Prehistory & the Development of Human Societies |date=2005 |publisher=Thames & Hudson |isbn=978-0-500-28531-2 |oclc=1091012125 }}</ref> ''Homo habilis'' was the hominin who used the tools for most of the Oldowan in Africa, but at about 1.9-1.8 million years ago [[Homo erectus]] inherited them. The Industry flourished in southern and eastern Africa between 2.6 and 1.7 million years ago, but was also spread out of Africa and into [[Eurasia]] by travelling bands of ''H. erectus'', who took it as far east as [[Java]] by 1.8 million years ago and [[North China (continent)|Northern China]] by 1.6 million years ago.{{fact|date=May 2020}}\n\n [[File:Biface (trihedral) Amar Merdeg, Mehran, Ilam, Lower Paleolithic, National Museum of Iran.jpg|thumb|left|upright|A biface (trihedral) from Amar Merdeg, Zagros foothills, Lower Paleolithic, National Museum of Iran]]\n[[Image:Hand axe spanish.gif|thumb|upright=1.25|A typical Acheulean handaxe; this example is from the Douro valley, [[Zamora (province)|Zamora]], Spain. The small flakes on the edge are from reworking.]]\n{{Commons category|Acheulean}}\n{{Main|Acheulean Industry}}\n\nEventually, more complex Mode 2 tools began to be developed through the [[Acheulean Industry]], named after the site of [[Saint-Acheul (Amiens)|Saint-Acheul]] in France. The Acheulean was characterised not by the core, but by the [[biface]], the most notable form of which was the [[hand axe]].<ref>Clarke's "bifacially flaked hand axes."</ref> The Acheulean first appears in the archaeological record as early as 1.7 million years ago in the [[Turkana District|West Turkana]] area of [[Kenya]] and contemporaneously in southern Africa.\n\nThe Leakeys, excavators at Olduvai, defined a "Developed Oldowan" Period in which they believed they saw evidence of an overlap in Oldowan and Acheulean. In their species-specific view of the two industries, Oldowan equated to ''H. habilis'' and Acheulean to ''H. erectus''. Developed Oldowan was assigned to ''habilis'' and Acheulean to ''erectus''. Subsequent dates on ''H. erectus'' pushed the fossils back to well before Acheulean tools; that is, ''H. erectus'' must have initially used Mode 1. There was no reason to think, therefore, that Developed Oldowan had to be ''habilis''; it could have been ''erectus''. Opponents of the view divide Developed Oldowan between Oldowan and Acheulean. There is no question, however, that ''habilis'' and ''erectus'' coexisted, as ''habilis'' fossils are found as late as 1.4 million years ago. Meanwhile, African ''H. erectus'' developed Mode 2. In any case a wave of Mode 2 then spread across Eurasia, resulting in use of both there. ''H. erectus'' may not have been the only hominin to leave Africa; European fossils are sometimes associated with ''[[Homo ergaster]]'', a contemporary of ''H. erectus'' in Africa.\n\nIn contrast to an Oldowan tool, which is the result of a fortuitous and probably [[ex tempore]] operation to obtain one sharp edge on a stone, an Acheulean tool is a planned result of a manufacturing process. The manufacturer begins with a blank, either a larger stone or a slab knocked off a larger rock. From this blank he or she removes large flakes, to be used as cores. Standing a core on edge on an anvil stone, he or she hits the exposed edge with centripetal blows of a hard hammer to roughly shape the implement. Then the piece must be worked over again, or retouched, with a soft hammer of wood or bone to produce a tool finely Knapped all over consisting of two convex surfaces intersecting in a sharp edge. Such a tool is used for slicing; concussion would destroy the edge and cut the hand.\n\nSome Mode 2 tools are disk-shaped, others ovoid, others leaf-shaped and pointed, and others elongated and pointed at the distal end, with a blunt surface at the proximal end, obviously used for drilling. Mode 2 tools are used for butchering; not being composite (having no haft) they are not very appropriate killing instruments. The killing must have been done some other way. Mode 2 tools are larger than Oldowan. The blank was ported to serve as an ongoing source of flakes until it was finally retouched as a finished tool itself. Edges were often sharpened by further retouching.\n\n [[File:Nucl\u00e9us Levallois La-Parrilla.png|thumb|upright=1.25|A tool made by the [[Levallois technique]]. This example is from La Parrilla (Valladolid, Spain).]]\n{{Commons category|Mousterian}}\n\n{{Main|Mousterian}}\n\nEventually, the Acheulean in Europe was replaced by a lithic technology known as the [[Mousterian Industry]], which was named after the site of [[Le Moustier]] in France, where examples were first uncovered in the 1860s. Evolving from the Acheulean, it adopted the [[Levallois technique]] to produce smaller and sharper knife-like tools as well as scrapers. Also known as the "prepared core technique," flakes are struck from worked cores and then subsequently retouched. <ref>Clarke's "flake tools from prepared cores."</ref> The Mousterian Industry was developed and used primarily by the [[Neanderthals]], a native European and Middle Eastern hominin species, but a broadly similar industry is contemporaneously widespread in Africa. <ref>{{Citation | last=Pettitt |first=Paul | year=2009 | contribution=The Rise of Modern Humans | title=The Human Past: World Prehistory and the Development of Human Societies | edition=2nd | editor-first=Chris | editor-last=Scarre | location=London | publisher=Thames and Hudson | pages=149\u2013151}}</ref>\n\n[[File:Middle Paleolithic stone tool known as Mousterian point discovered in the Darai Rockshelter in the Sirwan valley of Hawraman, Zagros.jpg|thumb|Middle Paleolithic stone tool known as Mousterian point, Darai Rockshelter, Zagros]]\n\n The widespread use of long [[lithic blade|blade]]s (rather than flakes) of the [[Upper Palaeolithic]] Mode 4 industries appeared during the [[Upper Palaeolithic]] between 50,000 and 10,000 years ago, although blades were produced in small quantities much earlier by Neanderthals.<ref>{{cite book | last1=Lewin | first1=R. |last2=Foley |first2=R. A. | year=2004 | title=Principles of Human Evolution |edition=2 | publisher=Blackwell Science |location=UK | isbn=0-632-04704-6 | page=311}}</ref> The [[Aurignacian]] culture seems to have been the first to rely largely on blades.<ref>Clarke's "punch-struck blades with steep retouch."</ref> The use of blades exponentially increases the efficiency of core usage compared to the Levallois flake technique, which had a similar advantage over Acheulean technology which was worked from cores.\n\n {{multiple image\n| align = right\n| image1 = Arp\u00f3n con microlitos.png\n| width1 = 100\n| alt1 = \n| caption1 = The most widely accepted hypothesis is that geometric microliths were used on projectiles such as this harpoon.\n| image2 = Tv\u00e6rmose arrow (Denmark).png\n| width2 = 100\n| alt2 = \n| caption2 = Trapezoid microliths and arrow with a trapeze used to strengthen the tip, found in a peat bog at Tv\u00e6rmose (Denmark)\n| footer = \n}}\n\n{{Main|Microlith}}\n\nMode 5 stone tools involve the production of [[microlith]]s, which were used in composite tools, mainly fastened to a shaft.<ref>Clarke's "microlithic components of composite artifacts."</ref> Examples include the [[Magdalenian]] culture. Such a technology makes much more efficient use of available materials like flint, although required greater skill in manufacturing the small flakes. Mounting sharp flint edges in a wood or bone handle is the key innovation in microliths, essentially because the handle gives the user protection against the flint and also improves leverage of the device.\n\n [[Image:N\u00e9olithique 0001.jpg|thumb|left|An array of [[Neolithic]] artifacts, including bracelets, axe heads, chisels, and polishing tools.]]\n[[File:Hache 222.1 Global fond.jpg|thumb|left|Polished Neolithic [[jadeitite]] axe from the Museum of Toulouse]]\n[[File:HMB Steinaxtmanufaktur Vinelz Jungsteinzeit 2700 BC.jpg|thumb|Axe heads found at a 2700 BC Neolithic manufacture site in Switzerland, arranged in the various stages of production from left to right]]\n\nIn prehistoric [[Japan]], ground stone tools appear during the [[Japanese Paleolithic]] period, that lasted from around 40,000 BC to 14,000 BC.<ref>"Prehistoric Japan, New perspectives on insular East Asia", Keiji Imamura, University of Hawaii Press, Honolulu, {{ISBN|0-8248-1853-9}}</ref>  Elsewhere, ground stone tools became important during the [[Neolithic]] period beginning about 10,000 BC. These ground or polished implements are manufactured from larger-grained materials such as [[basalt]], [[jade]] and [[jadeite]], [[Greenstone (archaeology)|greenstone]] and some forms of [[rhyolite]] which are not suitable for flaking. The greenstone industry was important in the [[English Lake District]], and is known as the [[Langdale axe industry]]. Ground stone implements included [[adze]]s, [[celt (tool)|celt]]s, and [[axe]]s, which were manufactured using a labour-intensive, time-consuming method of repeated grinding against an abrasive stone, often using water as a lubricant. Because of their coarse surfaces, some ground stone tools were used for grinding plant foods and were polished not just by intentional shaping, but also by use. [[Mano (stone)|Manos]] are hand stones used in conjunction with [[metate]]s for grinding corn or grain. Polishing increased the intrinsic [[mechanical strength]] of the axe. Polished stone axes were important for the widespread clearance of woods and forest during the Neolithic period, when crop and livestock farming developed on a large scale. They are distributed very widely and were traded over great distances since the best rock types were often very local. They also became venerated objects, and were frequently buried in [[long barrow]]s or [[round barrow]]s with their former owners.{{fact|date=May 2020}}\n\nDuring the [[Neolithic]] period, large axes were made from flint [[nodule (geology)|nodule]]s by knapping a rough shape, a so-called "rough-out". Such products were traded across a wide area. The rough-outs were then polished to give the surface a fine finish to create the axe head. Polishing not only increased the final strength of the product but also meant that the head could penetrate wood more easily.{{fact|date=May 2020}}\n[[File:Mar Dalan-Rawansar-Kermanshah.jpg|thumb|left|Small lunates from Epipaleolithic site of Mar Dalan, [[Rawansar]] , Kermanshah, Zagros]]\nThere were many sources of supply, including [[Grimes Graves]] in [[Suffolk]], [[Cissbury]] in [[Sussex]] and [[Spiennes]] near [[Mons]] in [[Belgium]] to mention but a few. In [[Great Britain|Britain]], there were numerous small quarries in [[downland]] areas where flint was removed for local use, for example.{{fact|date=May 2020}}\n\nMany other rocks were used to make axes from stones, including the [[Langdale axe industry]] as well as numerous other sites such as [[Penmaenmawr]] and [[Tievebulliagh]] in [[Co Antrim]], [[Ulster]]. In Langdale, there many [[outcrop]]s of the [[greenstone (archaeology)|greenstone]] were exploited, and knapped where the stone was extracted. The sites exhibit piles of waste flakes, as well as rejected rough-outs. Polishing improved the [[mechanical strength]] of the tools, so increasing their life and effectiveness. Many other tools were developed using the same techniques. Such products were traded across the country and abroad.{{fact|date=May 2020}}"}},
{"article_title": "Creativity", "pageid": "142910", "revid": "1062130045", "timestamp": "2021-12-26T13:49:44Z", "history_paths": [["Creativity --- Introduction ---", "Conceptual history"]], "categories": ["creativity", "aptitude", "cognition", "concepts in aesthetics", "concepts in metaphilosophy", "concepts in metaphysics", "concepts in the philosophy of mind", "critical thinking skills", "design", "imagination", "innovation economics", "mental processes", "metaphysics of mind", "problem solving skills", "product management", "science and technology studies", "thought"], "heading_tree": {"Creativity --- Introduction ---": {"Etymology": {}, "Definition": {}, "Aspects": {}, "Conceptual history": {"Ancient": {}, "Post-Enlightenment": {}, "Modern": {}}, "\"Four C\" model": {}, "Process theories": {"Incubation": {}, "Convergent and divergent thinking": {}, "Creative cognition approach": {}, "The Explicit\u2013Implicit Interaction (EII) theory": {}, "Conceptual blending": {}, "Honing theory": {}, "Everyday imaginative thought": {}, "Dialectical theory of creativity": {}, "Neuroeconomic framework for creative cognition": {}}, "Personal assessment": {"Creativity quotient": {}, "Psychometric approach": {}, "Social-personality approach": {}, "Self-report questionnaires": {}}, "Intelligence{{anchor|Creativity_and_intelligence}}": {"Creativity as a subset of intelligence": {}, "Intelligence as a subset of creativity": {}, "Creativity and intelligence as overlapping yet distinct constructs": {}, "Creativity and intelligence as coincident sets": {}, "Creativity and intelligence as disjoint sets": {}}, "Neuroscience": {"Working memory and the cerebellum": {}, "REM sleep": {}}, "Affect": {"Positive affect relations": {}}, "Computational creativity{{anchor|Creativity_and_artificial_intelligence}}": {}, "Creativity and mental health": {"Bipolar Disorders and Creativity": {}}, "Personality": {}, "Malevolent creativity": {"Crime": {}, "Predictive factors": {}}, "Cultural differences in creativity": {}, "Organizational creativity": {"Team composition": {}, "Team processes": {}, "Organizational culture": {}, "Constraints": {}}, "The sociology of creativity": {}, "Economic views": {}, "Fostering creativity": {"Managing the need for closure": {}}, "Education policies": {"Scotland": {}}, "Academic journals": {}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Creativity --- Introduction ---|Conceptual history": "{{Main|History of the concept of creativity}}\n[[File:Plato-raphael.jpg|thumb|150px|right|Greek philosophers like Plato rejected the concept of creativity, preferring to see art as a form of discovery. Asked in ''[[Republic (Plato)|The Republic]]'', "Will we say, of a painter, that he makes something?", Plato answers, "Certainly not, he merely [[mimesis|imitates]]."<ref name="Six Ideas p. 244">[[W\u0142adys\u0142aw Tatarkiewicz]], ''A History of Six Ideas: an Essay in Aesthetics'', p. 244.</ref>]]\n\n Most ancient cultures, including thinkers of [[Ancient Greece]],<ref name="Six Ideas p. 244" /> [[History of China#Ancient China|Ancient China]], and [[Outline of ancient India|Ancient India]],<ref name="Albert99">{{cite book|last=Albert|first= R. S.|author2=Runco, M. A.|year=1999|editor = Sternberg, R. J.|title= Handbook of Creativity|publisher= [[Cambridge University Press]]|chapter=A History of Research on Creativity}}</ref> lacked the concept of creativity, seeing art as a form of discovery and not creation. The [[Ancient Greece|ancient Greeks]] had no terms corresponding to "to create" or "creator" except for the expression "{{transl|grc|poiein}}" ("to make"), which only applied to {{transl|grc|poiesis}} (poetry) and to the {{transl|grc|poietes}} (poet, or "maker") who made it. [[Plato]] did not believe in art as a form of creation. Asked in ''[[Republic (Plato)|The Republic]]'',<ref>Plato, The Republic, Book X \u2013 [[wikisource:The Republic/Book X]]</ref> "Will we say, of a painter, that he makes something?", he answers, "Certainly not, he merely [[mimesis|imitates]]."<ref name="Six Ideas p. 244" />\n\nIt is commonly argued that the notion of "creativity" originated in [[Western culture]]s through [[Christianity]], as a matter of [[Revelation|divine inspiration]].<ref name="RuncoAlbert" /> According to the historian [[Daniel J. Boorstin]], "the early Western conception of creativity was the [[Genesis creation narrative|Biblical story of creation]] given in the ''[[Book of Genesis|Genesis]]''."<ref name="Albert2">{{cite book|last=Albert|first= R. S.|author2=Runco, M. A.|year=1999|editor = Sternberg, R. J.|title= Handbook of Creativity|publisher= [[Cambridge University Press]]|chapter=A History of Research on Creativity|page=5}}</ref> However, this is not creativity in the modern sense, which did not arise until the [[Renaissance]]. In the Judeo-Christian tradition, creativity was the sole province of God; humans were not considered to have the ability to create something new except as an expression of God's work.<ref name="NiuSternberg">{{cite journal|doi=10.1037/h0091265|last=Niu|first=Weihua|author2=Sternberg, Robert J.|title=The Philosophical Roots of Western and Eastern Conceptions of Creativity|journal=Journal of Theoretical and Philosophical Psychology|year=2006|volume=26|issue=1\u20132|pages=18\u201338|url=http://www.westga.edu/~stpp/JTPP_Aticles/26-2/THE1210.pdf|access-date=23 October 2010|url-status=dead|archive-url=https://www.webcitation.org/641OBVx0d?url=http://www.westga.edu/~stpp/JTPP_Aticles/26-2/THE1210.pdf|archive-date=18 December 2011}}; cf. [[Michel Weber]], "[https://www.academia.edu/3640181/_Creativity_Efficacy_and_Vision_Ethics_and_Psychology_in_an_Open_Universe_2006_ Creativity, Efficacy and Vision: Ethics and Psychology in an Open Universe]," in Michel Weber and Pierfrancesco Basile (eds.), ''Subjectivity, Process, and Rationality'', Frankfurt/Lancaster, ontos verlag, Process Thought XIV, 2006, pp. 263-281.</ref> A concept similar to that of Christianity existed in Greek culture. For instance, [[Muse]]s were seen as mediating inspiration from the Gods.<ref name="Dacey">{{cite book|last=Dacey|first=John|title=Encyclopedia of Creativity, Vol. 1|year=1999|isbn=978-0-12-227076-5|editor=Mark A. Runco |editor2=Steven R. Pritzer|chapter=Concepts of Creativity: A history|publisher=[[Elsevier]]}}</ref> Romans and Greeks invoked the concept of an external creative "[[daemon (classical mythology)|daemon]]" (Greek) or "[[Genius (mythology)|genius]]" (Latin), linked to the sacred or the divine. However, none of these views are similar to the modern concept of creativity, and the individual was not seen as the cause of creation until the [[Renaissance]].<ref name="Albert3">{{cite book|last=Albert|first= R. S.|author2=Runco, M. A.|year=1999|editor = Sternberg, R. J.|title= Handbook of Creativity|publisher= [[Cambridge University Press]]|chapter=A History of Research on Creativity|page=6}}</ref> It was during the Renaissance that creativity was first seen, not as a conduit for the divine, but from the abilities of "[[Great Man theory|great men]]".<ref name="Albert3" />\n\n The rejection of creativity in favor of discovery and the belief that individual creation was a conduit of the divine would dominate the West probably until the [[Renaissance]] and even later.<ref name="NiuSternberg" /> The development of the modern concept of creativity began in the [[Renaissance]], when creation began to be perceived as having originated from the abilities of the individual and not God. This could be attributed to the leading intellectual movement of the time, aptly named [[humanism]], which developed an intensely human-centric outlook on the world, valuing the intellect and achievement of the individual.<ref>{{Cite web|title = Humanism - Rome Reborn: The Vatican Library & Renaissance Culture {{!}} Exhibitions - Library of Congress|url = https://www.loc.gov/exhibits/vatican/humanism.html|website = www.loc.gov|date = 1993-01-08|access-date = 2015-11-23}}</ref> From this philosophy arose the [[Renaissance man]] (or polymath), an individual who embodies the principals of humanism in their ceaseless courtship with knowledge and creation.<ref>{{Cite web|title = Leonardo da Vinci {{!}} Italian artist, engineer, and scientist|url = http://www.britannica.com/biography/Leonardo-da-Vinci|website = Encyclop\u00e6dia Britannica|access-date = 2015-11-23}}</ref> One of the most well-known and immensely accomplished examples is [[Leonardo da Vinci]].\n\nHowever, this shift was gradual and would not become immediately apparent until the Enlightenment.<ref name="Albert3" /> By the 18th century and the [[Age of Enlightenment]], mention of creativity (notably in [[aesthetics]]), linked with the concept of [[imagination]], became more frequent.<ref name="Tatarkiewicz80">{{cite book |author=Tatarkiewicz, W\u0142adys\u0142aw |author-link=W\u0142adys\u0142aw Tatarkiewicz |title=A History of Six Ideas: an Essay in Aesthetics |location=Translated from the Polish by [[Christopher Kasparek]], The Hague |publisher=Martinus Nijhoff |year=1980}}</ref> In the writing of [[Thomas Hobbes]], imagination became a key element of human cognition;<ref name="RuncoAlbert" /> [[William Duff (writer)|William Duff]] was one of the first to identify imagination as a quality of [[genius]], typifying the separation being made between talent (productive, but breaking no new ground) and genius.<ref name="Dacey" />\n\nAs a direct and independent topic of study, creativity effectively received no attention until the 19th century.<ref name="Dacey" /> Runco and Albert argue that creativity as the subject of proper study began seriously to emerge in the late 19th century with the increased interest in individual differences inspired by the arrival of [[Darwinism]]. In particular, they refer to the work of [[Francis Galton]], who through his [[Eugenics|eugenicist]] outlook took a keen interest in the heritability of intelligence, with creativity taken as an aspect of genius.<ref name="RuncoAlbert" />\n\nIn the late 19th and early 20th centuries, leading mathematicians and scientists such as [[Hermann von Helmholtz]] (1896) and [[Henri Poincar\u00e9]] (1908) began to reflect on and publicly discuss their creative processes.\n\n The insights of Poincar\u00e9 and von Helmholtz were built on in early accounts of the creative process by pioneering theorists such as [[Graham Wallas]]<ref name="Wallas26">{{cite book |author=Wallas, G. |title=Art of Thought |url=https://archive.org/details/theartofthought |year=1926 |author-link=Graham Wallas}}</ref> and [[Max Wertheimer]]. In his work ''Art of Thought'', published in 1926, Wallas presented one of the first models of the creative process. In the Wallas stage model, creative insights and illuminations may be explained by a process consisting of 5 stages:\n:(i) ''[[Preparation (principle)|preparation]]'' (preparatory work on a problem that focuses the individual's mind on the problem and explores the problem's dimensions),\n:(ii) ''[[Incubation (psychology)|incubation]]'' (where the problem is internalized into the unconscious mind and nothing appears externally to be happening),\n:(iii) ''intimation'' (the creative person gets a "feeling" that a solution is on its way),\n:(iv) ''illumination'' or insight (where the creative idea bursts forth from its [[preconscious]] processing into conscious awareness);\n:(v) ''verification'' (where the idea is consciously verified, elaborated, and then applied).\nWallas' model is often treated as four stages, with "intimation" seen as a sub-stage.\n\nWallas considered creativity to be a legacy of the [[evolution]]ary process, which allowed humans to quickly adapt to rapidly changing environments. Simonton<ref name="Simonton99">{{cite book |author=Simonton, D. K. |year=1999 |title=Origins of genius: Darwinian perspectives on creativity |url=https://archive.org/details/originsofgeniusd00simo |url-access=registration |publisher=Oxford University Press|isbn=978-0-19-512879-6 }}</ref> provides an updated perspective on this view in his book, ''Origins of genius: Darwinian perspectives on creativity''.\n\nIn 1927, [[Alfred North Whitehead]] gave the Gifford Lectures at the University of Edinburgh, later published as ''[[Process and Reality]].''<ref>{{cite book|last=Whitehead|first=Alfred North|title=Process, and reality : an essay in cosmology ; Gifford Lectures delivered in the University of Edinburgh during the session 1927\u201328|year=1978|publisher=Free Press|location=New York|isbn=978-0-02-934580-1|edition=Corrected|url=https://archive.org/details/processrealitygi00alfr}}</ref> He is credited with having coined the term "creativity" to serve as the ultimate category of his metaphysical scheme: "Whitehead actually coined the term \u2013 our term, still the preferred currency of exchange among literature, science, and the arts. . . a term that quickly became so popular, so omnipresent, that its invention within living memory, and by Alfred North Whitehead of all people, quickly became occluded".<ref>{{cite journal|last=Meyer|first=Steven|title=Introduction: Whitehead Now|journal=Configurations|year=2005|volume=1|issue=13|pages=1\u201333|doi=10.1353/con.2007.0010}}. Cf. [[Michel Weber]] and Will Desmond (eds.). ''[https://www.academia.edu/279955/Handbook_of_Whiteheadian_Process_Thought Handbook of Whiteheadian Process Thought]'' (Frankfurt / Lancaster, Ontos Verlag, Process Thought X1 & X2, 2008) and Ronny Desmet & Michel Weber (edited by), ''[https://www.academia.edu/279940/Whitehead._The_Algebra_of_Metaphysics Whitehead. The Algebra of Metaphysics. Applied Process Metaphysics Summer Institute Memorandum]'', Louvain-la-Neuve, Les \u00c9ditions Chromatika, 2010.</ref>\n\nAlthough psychometric studies of creativity had been conducted by The London School of Psychology as early as 1927 with the work of H. L. Hargreaves into the Faculty of Imagination,<ref>{{cite journal | last1 = Hargreaves | first1 = H. L. | year = 1927 | title = The faculty of imagination: An enquiry concerning the existence of a general faculty, or group factor, of imagination | journal = British Journal of Psychology | volume = Monograph Supplement 3 | pages = 1\u201374 }}</ref> the formal [[Psychometrics|psychometric]] measurement of creativity, from the standpoint of orthodox [[Psychology|psychological]] literature, is usually considered to have begun with [[J. P. Guilford]]'s address to the [[American Psychological Association]] in 1950.<ref name="Sternberg99">{{cite book |author=Sternberg, R. J. |author2=Lubart, T. I. |chapter=The Concept of Creativity: Prospects and Paradigms |editor=Sternberg, R. J. |title=Handbook of Creativity |year=1999 |publisher= Cambridge University Press |author-link=Robert Sternberg |isbn=978-0-521-57285-9}}</ref> The address helped to popularize the study of creativity and to focus attention on scientific approaches to conceptualizing creativity. Statistical analyses led to the recognition of creativity (as measured) as a separate aspect of human cognition to [[Intelligence quotient|IQ]]-type intelligence, into which it had previously been subsumed. Guilford's work suggested that above a threshold level of IQ, the relationship between creativity and classically measured intelligence broke down.<ref name="Kozbelt">{{cite book|last=Kozbelt|first=Aaron|title=The Cambridge Handbook of Creativity|year=2010|publisher=[[Cambridge University Press]]|isbn=978-0-521-73025-9|author2=Beghetto, Ronald A.|author3=Runco, Mark A.|editor=[[James C. Kaufman]]|editor2=Robert J. Sternberg|chapter=Theories of Creativity|chapter-url-access=registration|chapter-url=https://archive.org/details/cambridgehandboo0000unse_x7r7}}</ref>"}},
{"article_title": "Projectile point", "pageid": "143830", "revid": "1062929282", "timestamp": "2021-12-31T06:34:34Z", "history_paths": [["Projectile point --- Introduction ---", "History in North America"]], "categories": ["projectile points", "lithics", "archaeological artefact types", "primitive technology", "primitive weapons", "stone age", "archaic period in north america", "j\u014dmon period", "paleolithic japan"], "heading_tree": {"Projectile point --- Introduction ---": {"History in North America": {"Types": {}, "North American types": {}}, "Gallery": {}, "See also": {}, "Notes": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Projectile point --- Introduction ---|History in North America": "A large variety of prehistoric arrowheads, dart points, javelin points, and spear points have been discovered. [[Chert]], [[obsidian]], [[quartzite]], [[quartz]], and many other rocks and minerals were commonly used to make points in North America.  The oldest projectile points found in North America were long thought to date from about 13,000 years ago, during the [[Paleo-Indian|Paleo-Indian period]], however recent evidence suggests that North American projectile points may date to as old as 15,500 years.<ref>{{cite news | url=https://www.nytimes.com/2011/03/25/science/25archeo.html?hpw | work=The New York Times | title=Clovis People Weren't First in Americas, Texas Spear Points Suggest | date=24 March 2011 | url-status=live | archive-url=https://web.archive.org/web/20150319035529/http://www.nytimes.com/2011/03/25/science/25archeo.html?hpw | archive-date=19 March 2015 }}</ref>  Some of the more famous Paleo-Indian types include [[Clovis point|Clovis]], [[Folsom point|Folsom]] and Dalton points.<ref>[http://www.theaaca.com/index.htm Authentic Artefacts Collectors Association] {{webarchive|url=https://web.archive.org/web/20081120201207/http://www.theaaca.com/index.htm |date=2008-11-20 }}</ref>\n\n Projectile points fall into two general types: [[dart (missile)|dart]], [[javelin]], or [[spear]] points and [[Arrowhead|arrow points]]. Larger points were used to tip [[atlatl]] javelins or darts and spears. Arrow points are smaller and lighter than dart points, and were used to tip arrows. The question of how to distinguish an arrow point from a point used on a larger projectile is non-trivial. According to some investigators, the best indication is the width of the [[hafting]] area, which is thought to correlate to the width of the shaft.<ref>Wyckoff 1964</ref> An alternative approach is to distinguish arrow points by their necessarily smaller size (weight, length, thickness).<ref>Thomas 1981</ref>\n\nProjectile points come in an amazing variety of shapes and styles, which vary according to chronological periods, cultural identities, and intended functions.\n\nTypological studies of projectile points have become more elaborate through the years. For instance, [[Gregory Perino]] began his categorical study of projectile point typology in the late 1950s. Collaborating with Robert Bell, he published a set of four volumes defining the known point types of that time. Perino followed this several years later with a three-volume study of "Selected Preforms, Points and Knives of the North American Indians".<ref>Fraser 2005</ref> Another recent set of typological studies of North American projectile points has been produced by Noel Justice.<ref>Justice 1987</ref><ref>Justice 2001</ref><ref>Justice 2002a</ref><ref>Justice 2002b</ref>\n\n * [[Bare Island projectile point]]\n* [[Barnes projectile point]]\n* [[Cascade point]]\n* [[Clovis point]]\n* [[Cumberland point]]\n* [[Eden point]]\n* [[Elko point]]\n* [[Folsom point]]\n* [[Greene projectile point]]\n* [[Jack's Reef pentagonal projectile point]]\n* [[Lamoka projectile point]]\n* [[Levanna projectile point]]\n* [[Neville archaeological site|Neville projectile point]] \n* [[Susquehanna broad projectile point]]\n* [[Plano point]]"}},
{"article_title": "Precision agriculture", "pageid": "144068", "revid": "1058965527", "timestamp": "2021-12-06T17:16:05Z", "history_paths": [["Precision agriculture --- Introduction ---", "History"]], "categories": ["agricultural revolutions", "agricultural soil science", "agricultural technology", "emerging technologies", "global positioning system", "applications of geographic information systems"], "heading_tree": {"Precision agriculture --- Introduction ---": {"History": {}, "Overview": {"Prescriptive planting": {}}, "Principles": {"Geolocating": {}, "Variables": {}, "Strategies": {}, "Implementing practices": {}}, "Usage around the world": {}, "Economic and environmental impacts": {}, "Emerging technologies": {"Robots": {}, "Drones and satellite imagery": {}, "The Internet of things": {}, "Smartphone applications": {}, "Machine learning": {}}, "Conferences": {}, "See also": {}, "Notes": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Precision agriculture --- Introduction ---|History": "{{See also|Timeline of agriculture and food technology}}\n\nPrecision agriculture is a key component of the third wave of modern [[Agricultural revolution (disambiguation)|agricultural revolutions]].  The first agricultural revolution was the increase of [[mechanized agriculture]], from 1900 to 1930. Each farmer produced enough food to feed about 26 people during this time.<ref name="ey.com">{{Cite web | url=https://consulting.ey.com/digital-agriculture-helping-to-feed-a-growing-world/ | title=Digital agriculture: Helping to feed a growing world| date=2017-02-23}}</ref> The 1960s prompted the [[Green Revolution]] with new methods of genetic modification, which led to each farmer feeding about 156 people.<ref name="ey.com"/> It is expected that by 2050, the global population will reach about 9.6 billion, and food production must effectively double from current levels in order to feed every mouth. With new technological advancements in the agricultural revolution of precision farming, each farmer will be able to feed 265 people on the same acreage.<ref name="ey.com"/>"}},
{"article_title": "Knapping", "pageid": "144551", "revid": "1062780737", "timestamp": "2021-12-30T13:51:41Z", "history_paths": [["Knapping --- Introduction ---", "Uses"], ["Knapping --- Introduction ---", "Contemporary study"]], "categories": ["lithics", "primitive technology", "natural materials", "experimental archaeology"], "heading_tree": {"Knapping --- Introduction ---": {"Method": {"Tools": {}}, "Uses": {}, "Health hazards": {}, "Contemporary study": {}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Knapping --- Introduction ---|Uses": "[[File:Aztec sacrificial knives.jpg|thumb|right|[[Aztec]] stone knives]]\n[[File:Steinschloss.jpg|thumb|right|A gun-flint mounted in the jaws of a flintlock musket]]\n[[File:Stratford_St_Mary_church_April_2005.JPG|thumb|right|Knapped flint walls and [[flushwork]] at the church of [[Stratford St. Mary]]]]\nIn cultures that have not adopted metalworking technologies, the production of stone tools by knappers is common, but in modern cultures the making of such tools is the domain of [[experimental archaeology|experimental archaeologists]] and hobbyists. [[Archaeologist]]s usually undertake the task so that they can better understand how prehistoric [[stone tool]]s were made.\n\nKnapping is often learned by outdoor enthusiasts.\n\nKnapping ''gun flints'', used by [[Flintlock mechanism|flintlock firearms]] was formerly a major industry in flint bearing locations, such as [[Brandon, Suffolk|Brandon]] in [[Suffolk]], England and the small towns of [[Meusnes]] and [[Couffy]] in France.<ref name="ancientcrafts" /> Meusnes has a small museum dedicated to the industry.\n\nIn 1804, during the [[Napoleonic Wars]], Brandon was supplying over 400,000 flints a month for use by the British Army and Navy.<ref name="whittaker">{{cite journal | url=http://web.grinnell.edu/anthropology/Faculty/JohnWhittaker/Articles/2001_The_Oldest_British.pdf | title=The Oldest British Industry: continuity and obsolescence in a flintknapper's sample set | author=Whittaker, John | journal=Antiquity | year=2001 | volume=75 | issue=288 | pages=382\u201390 | doi=10.1017/s0003598x00061032| s2cid=163235035 }}</ref> Brandon knappers made gun flints for export to Africa as late as the 1960s.\n\nKnapping for building purposes is still a skill that is practiced in the flint-bearing regions of southern England, such as [[Sussex]], Suffolk and [[Norfolk]], and in northern France, especially [[Brittany]] and [[Normandy]], where there is a resurgence of the craft due to government funding.<ref>{{Cite web|url=http://www.flintknapping.co.uk/arch.html|title = Architectural flintwork}}</ref>", "Knapping --- Introduction ---|Contemporary study": "[[File:Ense\u00f1ando a tallar.jpg|thumb|150px|right|French prehistorian [[Jacques Tixier]] offers modern training in stone knapping.]] \nModern American interest in knapping can be traced back <ref>Whittaker 1994:56-58</ref> to the study of a [[California]] Native American called [[Ishi]] who lived in the early twentieth century. Ishi taught scholars and academics traditional methods of making stone tools and how to use them for survival in the wild. Early European explorers to the New world were also exposed to flint knapping techniques. Additionally, several pioneering nineteenth-century European experimental knappers are also known and in the late 1960s and early 1970s experimental archaeologist [[Don Crabtree]] published texts such as "Experiments in Flintworking". [[Fran\u00e7ois Bordes]] was an early writer on [[Old World]] knapping; he experimented with ways to replicate stone tools found across [[Western Europe]]. These authors helped to ignite a small craze in knapping among archaeologists and prehistorians.\n\nEnglish archaeologist [[Phil Harding (archaeologist)|Phil Harding]] is another contemporary expert, whose exposure on the television series [[Time Team]] has led to him being a familiar figure in the UK and beyond. Many groups, with members from all walks of life, can now be found across the United States and Europe. These organizations continue to demonstrate and teach various ways of shaping stone tools."}},
{"article_title": "Universal joint", "pageid": "144948", "revid": "1061092239", "timestamp": "2021-12-19T16:19:20Z", "history_paths": [["Universal joint --- Introduction ---", "History"]], "categories": ["rotating shaft couplings", "mechanisms (engineering)", "automotive transmission technologies", "articles containing video clips"], "heading_tree": {"Universal joint --- Introduction ---": {"History": {}, "Equation of motion": {}, "Double Cardan shaft": {}, "Double Cardan joint": {"Thompson coupling": {}}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Universal joint --- Introduction ---|History": "[[File:Universal Shaft.ogv|thumbnail|This video shows different parts and operation of the universal shaft.]]\n\nThe main concept of the universal joint is based on the design of [[gimbal]]s, which have been in use since antiquity. One anticipation of the universal joint was its use by the ancient Greeks on [[ballistae]].<ref>see: "Universal Joint - Invented by Gerolamo Cardano" {{cite web |url=http://www.edubilla.com/invention/universal-joint/ |title=Archived copy |access-date=2017-04-21 |url-status=live |archive-url=https://web.archive.org/web/20170422130444/http://www.edubilla.com/invention/universal-joint/ |archive-date=2017-04-22 }}</ref> In Europe the universal joint is often called the Cardano joint or [[Cardan shaft]], after the Italian mathematician [[Gerolamo Cardano]]; however, in his writings, he mentioned only gimbal mountings, not universal joints.<ref>See:\n* Tony Rothman (2013) "Cardano v. Tartaglia: The Great Feud Goes Supernatural," p. 25. Available on-line at: [https://arxiv.org/ftp/arxiv/papers/1308/1308.2181.pdf Arxiv.org]. (Note that Rothman mentions Wikipedia's error regarding Cardano's supposed invention of the universal joint.)\n* Hans-Christoph Seherr-Thoss, Friedrich Schmelz, Erich Aucktor, ''Universal Joints and Driveshafts: Analysis, Design, Applications'' (Berlin, Germany: Springer Verlag, 1992), [https://books.google.com/books?id=-iLyCAAAQBAJ&pg=PA1#v=onepage&q&f=false p. 1.]\n* Marie Boas, ''The Scientific Renaissance: 1450-1630'' (New York, New York: Harper Brothers, 1962), [https://archive.org/stream/scientificrenais007153mbp#page/n209/mode/2up p. 186] {{webarchive|url=https://web.archive.org/web/20160411103028/https://archive.org/stream/scientificrenais007153mbp |date=2016-04-11 }}.\n* James Eckman, ''Jerome Cardan'' (Baltimore, Maryland: The Johns Hopkins Press, 1946.), p. 77.\n* Hieronymi Cardanime (Gerolamo Cardano), ''De Subtilitate Libri XXI.'' (On subtle things in 21 books) (Basel, Switzerland: Sebastian Henric Petri, 1553), ''Liber XVII. De Artibus, Artificiosisque; rebus.'' (Book 17. On crafts and ingenious devices), p. 817. (Note: (1) This book is a reprint of the 1500 original. (2) In the margin of p. 817 is printed: ''Sedes mira'' (miraculous chair).) [https://archive.org/stream/immagineDE295MiscellaneaOpal#page/n895/mode/2up From p. 817:] {{webarchive|url=https://web.archive.org/web/20171011035211/https://archive.org/stream/immagineDE295MiscellaneaOpal |date=2017-10-11 }} ''"Simili ratione invent\u0169 est, ut C\u00e6saris sedes ita disponeretur, ut quocumque situ constituatur, ille immobilis, ac commod\u00e8 dum vehitur sedeat. Hoc tractum ex armillarum ratione: cum enim circuli tres chalybei constituentur, polis sursum, deorsum, ant\u00e8, retro, dextra ac sinistra mobilibus, cum plures non possint esse situs, necesse est ipsum in essedo quomodocumque agatur quiescere perpetu\u00f2."'' (By similar reasoning, [it] has been found that the Emperor's chair might be so arranged that he [remain] fixed in whatever orientation be decided and he sit comfortably while he is transported. This is based on the logic of the gimbal mounting: the three steel rings are arranged by the movable poles [i.e., ends of the axes] upwards, downwards, forwards, backwards, right and left, when more [motions] cannot be allowed, [because it] is necessary [that] he in the carriage somehow be made to remain still constantly.)\n* Hieronymi Cardani (Gerolamo Cardano), ''Mediolanensis Philosophi ac Medici Celeberrimi Operum'' [Of the very famous works of the Milanese philosopher and physician] (Lyon (Lugdunum), France: Jean Antoine Huguetan and Marc Antoine Ravaud, 1663), vol. 10: ''Opuscula miscellanea'' (Miscellaneous works), ''Paralipomenon'' (Supplement), ''Liber V. De rebus factis raris & artificiis'' (Book 5. On rare and ingeniously made things), ''Caput VII. De Armillarum instrumento'' (Chapter 7. On the armillary), [https://books.google.com/books?id=kgxTAAAAcAAJ&pg=PA488#v=onepage&q&f=false pp. 488-489.]</ref>\n\nThe mechanism was later described in ''Technica curiosa sive mirabilia artis'' (1664) by [[Gaspar Schott]], who mistakenly claimed that it was a [[constant-velocity joint]].<ref name="Mills2007">Mills, Allan, "Robert Hooke's 'universal joint' and its application to sundials and the sundial-clock", ''Notes & Records of the Royal Society'', 2007, accessed [http://rsnr.royalsocietypublishing.org/content/61/2/219.full.pdf+html online] {{webarchive|url=https://web.archive.org/web/20150925130716/http://rsnr.royalsocietypublishing.org/content/61/2/219.full.pdf+html |date=2015-09-25 }} 2010-06-16</ref><ref>Gasparis Schotti, ''Technica Curiosa, sive Mirabilia Artis, Libris XII. \u2026 '' [Curious works of skill, or marvelous works of craftsmanship] (Nuremberg (Norimberga), (Germany): Johannes Andreas Endter & Wolfgang Endter, 1664), ''Liber IX. Mirabilia Chronometrica, \u2026 '' (Book 9. Marvelous Clocks, \u2026 ), ''Caput V. Signa chronometrica optica, seu indices.'' (Chapter 5. Marvelous visual clocks, or clocks with hands), [https://books.google.com/books?id=dhRTAAAAcAAJ&pg=PA664#v=onepage&q&f=false pp. 664-665:] ''Propositio XX. Indicem sinuosum & obliquatum per anfractus quosvis, sine Rotis dentatis quocumque lubet educere.'' (Proposition 20. [How], without any gears, to lead the twisting, turning pointer [i.e., the shaft that drives the clock's hands] through any bend one pleases.) In the margin is printed: ''Vide Iconism. VII. Fig. 32.'' (See [https://books.google.com/books?id=DKPSEzEWz8EC&pg=PA662-IA2#v=onepage&q&f=false Plate 7, Figure 32.]), which depicts Schott's universal joint. Schott first notes that there may be occasions when a clock's gear works and its face can't be conveniently aligned; e.g., public clocks installed in towers. He then mentions, in the description of its construction (''Technasma'', the Greek word for "artifice"), that the universal joint resembles a gimbal that is used to hold an oil lamp so that it won't spill oil. Schott's joint consists of two forks (''fuscinula''), each of which consists of a shaft to which a metal strip, bent into a semicircle, is attached to one end. Near each end of the semicircle, a hole is drilled. A cross with four perpendicular arms (''crux sive 4 brachia'') is also made. The holes in each semicircle fit over the ends of an opposing pair of arms. The angle between the shafts must be greater than a right angle. In discussing the joint's motion (''Motus''), Schott claims that the two shafts move at the same speed (i.e., they form a constant-velocity joint): ''" \u2026 horum autem ductum necesse est sequatur & altera fuscinula, parique cum priore illa feratur velocitate: unde si fuerit unius fuscinulae motus regularis circularis, erit similis & alterius \u2026 "'' ( \u2026 but this driven [fork] must follow the other [driving] fork, and it be born at a speed equal to the former: whence if one fork's motion were regularly circular, it will be similarly with the other \u2026 ).</ref><ref>For a (partial) history of universal joints, see: Robert Willis, ''Principles of Mechanism'' \u2026 , 2nd ed. (London, England: Longmans, Green, and Co., 1870), Part the Fifth: On Universal Joints, [https://books.google.com/books?id=KFjHSfh561MC&pg=PA437#v=onepage&q&f=false pp. 437-457.]</ref> Shortly afterward, between 1667 and 1675, [[Robert Hooke]] analysed the joint and found that its speed of rotation was nonuniform, but that this property could be used to track the motion of the shadow on the face of a sundial.<ref name="Mills2007"/> In fact, the component of the [[equation of time]] which accounts for the tilt of the equatorial plane relative to the ecliptic is entirely analogous to the mathematical description of the universal joint. The first recorded use of the term ''universal joint'' for this device was by Hooke in 1676, in his book ''Helioscopes''.<ref>"universal, ''a. (adv.)'' and ''n.''", para.13, Oxford English Dictionary Online, accessed 2010-06-16</ref><ref>Hooke first described a universal joint in [[Johannes Hevelius|Hevelius']] instrument in: Robert Hooke, ''Animadversions on the first part of the Machina Coelestis'' \u2026 (London, England: John Martyn, 1674), [https://books.google.com/books?id=KAtPAAAAcAAJ&pg=PA73#v=onepage&q&f=false p. 73.] Here he calls the joint a "universal Instrument". From page 73: I shall show " \u2026 what use I have made of this Joynt, for a universal Instrument for Dialling, for equalling of Time, for making the Hand of a Clock move in the Shadow of a Style, and for performing a multitude of other Mechanical Operations." The joint is depicted on Plate X, Fig.s 22 and 23, which are available at: [http://posner.library.cmu.edu/Posner/books/pages.cgi?call=530_H78AA&layout=vol0/part0/copy0&file=0093 Posner Memorial Collection - Carnegie Mellon University] {{webarchive|url=https://web.archive.org/web/20151117025019/http://posner.library.cmu.edu/Posner/books/pages.cgi?call=530_H78AA&layout=vol0%2Fpart0%2Fcopy0&file=0093 |date=2015-11-17 }}</ref><ref>Robert Hooke, ''A Description of Helioscopes, and Some Other Instruments'' (London, England: John Martyn, 1676), p. 14. [https://books.google.com/books?id=KQtPAAAAcAAJ&pg=PA14#v=onepage&q&f=false From p. 14:] "The ''Universal Joynt'' for all these manner of Operations, having not had time to describe the last Exercise, I shall now more particularly explain." Illustrations of Hooke's universal joint appear on p. 40, Fig.s 9 and 10; available at: [http://www.e-rara.ch/zut/content/pageview/731094 ETU Library ; Zurich, Switzerland] {{webarchive|url=https://web.archive.org/web/20150923225412/http://www.e-rara.ch/zut/content/pageview/731094 |date=2015-09-23 }}.</ref> He published a description in 1678,<ref name=Berthoud>Review of Ferdinand Berthoud's Treatise on Marine Clocks, Appendix Art. VIII, [https://books.google.com/books?id=JYMCAAAAYAAJ&pg=PA565 The Monthly Review or Literary Journal], Vol. L, 1774; see footnote, page 565.</ref> resulting in the use of the term ''Hooke's joint'' in the English-speaking world. In 1683, Hooke proposed a solution to the nonuniform rotary speed of the universal joint: a pair of Hooke's joints 90\u00b0 out of phase at either end of an intermediate shaft, an arrangement that is now known as a type of [[constant-velocity joint]].<ref name="Mills2007"/><ref>Gunther, Robert Theodore, ''Early Science in Oxford'', vol. 7: "Life and work of Robert Hooke, Part II" (Oxford, England:  Dawsons of Pall Mall, 1930), pp. 621\u2013622.</ref> [[Christopher Polhem]] of Sweden later re-invented the universal joint, giving rise to the name ''Polhemsknut'' ("Polhem knot") in Swedish.\n\nIn 1841, the English scientist [[Robert Willis (engineer)|Robert Willis]] analyzed the motion of the universal joint.<ref>Willis, Robert, ''Principles of Mechanisms'', \u2026 (London, England: John W. Parker, 1841), [https://books.google.com/books?id=1CCEKSqQaqcC&pg=PA272#v=onepage&q&f=false pp. 272-284.]</ref> By 1845, the French engineer and mathematician [[Jean-Victor Poncelet]] had analyzed the movement of the universal joint using spherical trigonometry.<ref>J. V. Poncelet, ''Trait\u00e9 de m\u00e9canique appliqu\u00e9e aux machines'', Part 1 (Li\u00e9ge, France: Librairie scientifique et industrielle, 1845), [https://books.google.com/books?id=Qqw-AAAAYAAJ&pg=PA121#v=onepage&q&f=false pp. 121-124.]</ref>\n\nThe term ''universal joint'' was used in the 18th century<ref name=Berthoud /> and was in common use in the 19th century. Edmund Morewood's 1844 patent for a metal coating machine called for a universal joint, by that name, to accommodate small alignment errors between the engine and rolling mill shafts.<ref>Edmund P. Morewood, Improvement in Coating Iron and Copper, [http://www.google.com/patents?id=EidCAAAAEBAJ U.S. Patent 3,746], Sept. 17, 1844.</ref> Ephriam Shay's [[Shay locomotive|locomotive]] patent of 1881, for example, used double universal joints in the locomotive's [[drive shaft]].<ref>Ephraim Shay, Locomotive-Engine, [http://www.google.com/patents?id=RvpGAAAAEBAJ U.S. Patent 242,992], June 14, 1881.</ref> Charles Amidon used a much smaller universal joint in his [[Brace (tool)|bit-brace]] patented 1884.<ref>Charles H. Amidon, Bit-Brace, [http://www.google.com/patents?id=RhdpAAAAEBAJ U.S. Patent 298,542], May 13, 1884.</ref> [[Beauchamp Tower]]'s spherical, rotary, high speed steam engine used an adaptation of the universal joint circa 1885.<ref>{{cite web\n  |author=Douglas Self \n  |author-link=Douglas Self \n  |url=http://www.douglas-self.com/MUSEUM/POWER/tower/tower.htm\n  |title=The Tower Spherical Engine\n}}</ref>\n\nThe term ''Cardan joint'' appears to be a latecomer to the English language. Many early uses in the 19th century appear in translations from [[French language|French]] or are strongly influenced by French usage. Examples include an 1868 report on the [[Exposition Universelle (1867)|''Exposition Universelle'' of 1867]]<ref>William P. Blake, Report of the Commissioner to the Paris Exposition, 1867, Chapter 1, [https://books.google.com/books?id=peENdsQu6cgC&pg=PA257 Transactions of the California State Agricultural Society, During the Years 1866 and 1867], Vol X, Gelwicks, Sacramento, 1868.</ref> and an article on the [[dynamometer]] translated from French in 1881.<ref>The Dynamometer Balance, [Van Nostrand's Engineering Magazine], Vol. XXV, No. CLVI (Dec. 1881); page 471.</ref>"}},
{"article_title": "Windpump", "pageid": "145193", "revid": "1058851912", "timestamp": "2021-12-06T00:03:12Z", "history_paths": [["Windpump --- Introduction ---"], ["Windpump --- Introduction ---", "Worldwide use"]], "categories": ["windpumps", "windmills", "energy harvesting", "sustainable technologies", "wind power", "water supply infrastructure", "water wells", "iranian inventions"], "heading_tree": {"Windpump --- Introduction ---": {"Worldwide use": {}, "Construction": {}, "Multi-bladed windpumps": {}, "Fundamental problems of multi-bladed windpumps": {"Inefficient rotor": {}, "Poor load matching": {}, "Cyclic torque variation": {}}, "Development of improved windpumps": {"USDA experiments at Texas": {}, "Fluttering windpumps": {}, "Variable stroke windpump": {}, "Vertical axis wind pump (VAWP)": {}}, "Combinations": {"''Tjasker''": {}, "Thai windpumps": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Windpump --- Introduction ---": "{{Short description|A windmill for pumping water}}\n\nA '''windpump''' is a type of [[windmill]] which is used for pumping [[water]].\n\n[[File:Molendeolifant.jpg|thumb|[[De Olifant, Burdaard|De Olifant]] at [[Burdaard]], [[Friesland]]]]\nWindpumps were used to pump water since at least the 9th century in what is now [[Afghanistan]], [[Iran]] and [[Pakistan]].<ref>{{cite book |first=Adam |last=Lucas |year=2006 |title=Wind, Water, Work: Ancient and Medieval Milling Technology |publisher=Brill Publishers |isbn=90-04-14649-0 |page=61}}</ref> The use of wind pumps became widespread across the [[Muslim world]] and later spread to [[China]] and [[Indian subcontinent|India]].<ref>{{cite web|url=http://home.swipnet.se/islam/articles/HistoryofSciences.htm|archive-url=https://web.archive.org/web/20070524071743/http://home.swipnet.se/islam/articles/HistoryofSciences.htm|archive-date=May 24, 2007|title=History of Sciences in the Islamic World|website=swipnet.se|access-date=August 20, 2021}}</ref> Windmills were later used extensively in Europe, particularly in the [[Netherlands]] and the [[East Anglia]] area of [[Great Britain]], from the late [[Middle Ages]] onwards, to drain land for agricultural or building purposes.\n\n[[Simon Stevin]]'s work in the ''waterstaet'' involved improvements to the [[sluice]]s and [[spillway]]s to control [[flood]]ing. [[Windmill]]s were already in use to pump the water out, but in ''Van de Molens'' (''On mills''), he suggested improvements, including the idea that the wheels should move slowly, and a better system for meshing of the [[gear teeth]]. These improvements increased the efficiency of the windmills used to pump water out of the [[polder]]s by three times. He received a [[patent]] on his innovation in 1586.<ref name=isis/>\n\nEight- to ten-bladed windmills were used in the [[Region of Murcia]], [[Spain]], to raise water for irrigation purposes.<ref>{{cite web|url=http://www.yachtmollymawk.com/2008/11/spanish-water-works/|title=Spanish Water Works|last=Schinas|first=Jill|website=yachtmollymawk.com|year=2008|access-date=August 20, 2021}}</ref> The drive from the windmill's rotor was led down through the tower and back out through the wall to turn a large wheel known as a ''[[noria]]''. The ''noria'' supported a bucket chain which dangled down into the well. The buckets were traditionally made of wood or clay. These windmills remained in use until the 1950s, and many of the towers are still standing.\n\nEarly immigrants to the [[New World]] brought with them the technology of windmills from Europe.<ref name="Brief History">{{cite web|url=http://www.windmillersgazette.com/history.html|archive-url=https://web.archive.org/web/20111007162315/http://www.windmillersgazette.com/history.html|archive-date=October 7, 2011|website=windmillersgazette.com|title=Brief History of Windmills in the New World|last=Baker|first=T. Lindsay|access-date=August 20, 2021}}</ref> On US farms, particularly on the [[Great Plains]], wind pumps were used to pump water from farm wells for cattle. In California and some other states, the windmill was part of a self-contained domestic water system, including a hand-dug well and a redwood water tower supporting a redwood tank and enclosed by redwood siding ([[tankhouse]]). The self-regulating farm wind pump was invented by [[Daniel Halladay]] in 1854.<ref name="Brief History" /><ref>{{cite journal|url=https://www.fnal.gov/pub/ferminews/ferminews03-02-14/p4.html|title=Historic Turns in The Windmill City|last=Clements|first=Elizabeth|journal=Fermi News|volume=26|issue=3|year=2003|publisher=[[Fermilab]]|access-date=August 20, 2021}}</ref> Eventually, steel blades and steel towers replaced wooden construction, and at their peak in 1930, an estimated 600,000 units were in use, with capacity equivalent to 150 megawatts.<ref>{{cite book|title=Wind Energy Comes of Age|last=Gipe|first=Paul|pages=123\u2013127|publisher=John Wiley and Sons|year=1995|isbn=0-471-10924-X}}</ref> Very large lighter wind pumps in Australia directly crank the pump with the rotor of the windmill. Extra back gearing between small rotors for high wind areas and the pump crank prevents trying to push the pump rods down on the downstroke faster than they can fall by gravity. Otherwise pumping too fast leads to the pump rods buckling, making the seal of the stuffing box leak and wearing through the wall of the rising main (UK) or the drop-pipe (US) so all output is lost.\n\nThe multi-bladed wind pump or wind [[turbine]] atop a lattice tower made of wood or steel hence became, for many years, a fixture of the landscape throughout rural America.<ref>{{cite web|url=https://www.semprius.com/wind-turbines-vs-windmills/|title=Wind Turbines vs. Windmills: What's the Difference?|last=Duval|first=George|website=semprius.com|date=July 18, 2021|access-date=August 20, 2021}}</ref> These mills, made by a variety of manufacturers, featured many blades so that they would turn slowly with considerable [[torque]] in moderate winds and be self-regulating in high winds. A tower-top [[Transmission (mechanics)|gearbox]] and [[crankshaft]] converted the rotary motion into reciprocating strokes carried downward through a rod to the pump cylinder below. Today, rising energy costs and improved pumping technology are increasing interest in the use of this once declining technology.\n\n [[File:Wicken Fen Windpump.jpg|thumb|A working wooden windpump on [[The Fens]] in [[Cambridgeshire]], UK]]\nThe [[Netherlands]] is well known for its windmills. Most of these iconic structures situated along the edge of [[polders]] are actually windpumps, designed to drain the land. These are particularly important as much of the country lies below [[sea level]].\n\nIn the UK, the term ''windpump'' is rarely used, and they are better known as ''drainage windmills''. Many of these were built in [[The Broads]] and [[The Fens]] of [[East Anglia]] for the draining of land, but most of them have since been replaced by [[diesel fuel|diesel]] or electric powered pumps.<ref>{{cite book|url=https://books.google.com/books?id=K-JRAQAAIAAJ&pg=PA106|page=106|title=The Norfolk Broads: A Landscape History|last=Williamson|first=Tom|publisher=Manchester University Press|year=1997|isbn=9780719048005}}</ref> Many of the original windmills still stand in a derelict state although some have been restored.<sup>[needs citation]</sup>\n\nWindpumps are used extensively in [[Southern Africa]], Australia, and on farms and ranches in the central plains and Southwest of the United States. In South Africa and Namibia thousands of windpumps are still operating. These are mostly used to provide water for human use as well as drinking water for large sheep stocks.\n\n[[Kenya]] has also benefited from the African development of windpump technologies. At the end of the 1970s, the UK [[NGO]] [[Intermediate Technology Development Group]] provided engineering support to the Kenyan company Bobs Harries Engineering Ltd for the development of the Kijito windpumps. Bobs Harries Engineering Ltd is still manufacturing the Kijito windpumps, and more than 300 of them are operating in the whole of [[East Africa]].{{citation needed|date=August 2021}}\n\nIn many parts of the world, a [[rope pump]] is being used in conjunction with wind turbines. This easy-to- construct pump works by pulling a knotted rope through a pipe (usually a simple PVC pipe) causing the water to be pulled up into the pipe. This type of pump has become common in [[Nicaragua]] and other places.{{citation needed|date=August 2021}}\n\n To construct a windpump, the bladed rotor needs to be matched to the pump. With non-electric windpumps, high [[Blade solidity|solidity]] rotors are best used in conjunction with positive displacement (piston) pumps, because single-acting piston pumps need about three times as much torque to start them as to keep them going. Low solidity rotors, on the other hand, are best used with [[centrifugal pump]]s, [[waterladder pump]]s and chain and washer pumps, where the torque needed by the pump for starting is less than that needed for running at design speed. Low solidity rotors are best used if they are intended to drive an electricity generator; which in turn can drive the pump.<ref>[http://www.fao.org/docrep/010/ah810e/AH810E10.htm Water lifting devices; matching bladed rotors to pumps]</ref>\n\n [[File:Wind-powered-agricultural-pump-1.jpg|thumb|Wind powered water pump on Oak Park Farm, Shedd, Oregon.]]\n[[File:Windmill in far western NSW.jpg|thumb|Windpump in far western [[NSW]].]]\nMulti-bladed wind pumps can be found worldwide and are manufactured in the United States, Argentina, China, New Zealand, South Africa, and Australia. Commonly known in the US and Canada as a "weathercock" because it behaves much like a traditional weather vane, moving with the direction of the wind (but also measuring wind speed).The Butler brand added improvements to the technology of windpumps in 1897, 1898 and 1905<ref>http://www.vintagewindmillpartslist.com/sitebuildercontent/sitebuilderfiles/butlerpictorial.pdf</ref> A 16 ft (4.8 m) diameter wind pump can lift up to 1600 US gallons (about 6.4 metric tons) of water per hour to an elevation of 100 ft with a 15 to 20 mph wind (24\u201332 km/h).<ref>[http://www.ironmanwindmill.com Iron Man Windmill Website pumping capacity calculator], retrieved January 15, 2011</ref> However they take a strong wind to start so they turn over the crank of the piston pump. Wind pumps require little maintenance\u2014usually only a change of gear box oil annually.<ref>[http://www.aermotorwindmill.com/Sales/CommonQuestions.asp Aermotor Web site frequently asked questions], retrieved Sept. 17, 2008</ref> An estimated 60,000 wind pumps are still in use in the United States. They are particularly attractive for use at remote sites where electric power is not available and maintenance is difficult to provide.<ref>http://www.windmill-parts.com/index.html\n</ref>\nA common multi-bladed windpump usefully pumps with about 4%\u20138% of the annual windpower passing through the area it sweeps<ref>[http://www.nrel.gov/docs/fy03osti/30361.pdf Argaw, N.,"Renewable Energy for Water Pumping Applications in Rural Villages",2003, NREL Report 30361, page 27]</ref><ref>[http://www.cprl.ars.usda.gov/REMM%20Pubs/1997%20Performance%20and%20Economic%20Comparison%20of%20a%20Mechanical%20Windmill%20to%20a%20Wind-Electric%20Water%20Pumping%20System.pdf Brian Vick, Nolan Clark "Performance and Economic Comparison of a Mechanical Windmill to Wind-Electric Water Pumping System", 1997, USDA-Agricultural Research Service, see Figure-2]</ref> This lower conversion is due to poor load matching between wind rotors and fixed-stroke piston pumps.\n\n \n [[File:Derelict windpump with water tank in the foreground next to the Boorowa railway in Galong NSW Australia.JPG|thumb|Derelict water tank with windmill in the background]]\nThe main design feature of a multi-bladed rotor is "high starting torque", which is necessary for cranking a piston pump operation. Once started a multi-bladed rotor runs at too high a tipspeed ratio at less than its best efficiency of 30%.<ref name="Hau 2005, page 101">Hau, Erich "Wind Turbines", 2005, page 101, Fig.5-10</ref> On the other hand, modern wind rotors can operate at an aerodynamic efficiency of more than 40% at higher tipspeed ratio for a smaller swirl added and wasted to the wind.<ref name="Hau 2005, page 101"/> But they would need a highly variable stroke mechanism rather than just a crank to piston pump.\n\n \nA multi-bladed windmill is a mechanical device with a piston pump. Because a piston pump has a fixed stroke, the energy demand of this type of pump is proportional to pump speed only. On the other hand, the energy supply of a wind rotor is proportional to the cube of wind speed. Because of that, a wind rotor runs at over speed (more speed than needed), yielding a loss of aerodynamic efficiency.\n\nA variable stroke would match the rotor speed according to wind speed, functioning like a "variable-speed generator". The flow rate of variable stroke windpump can be increased two times, compared to fixed stroke windpumps at the same wind speed.<ref name="ena.com.tr">[https://web.archive.org/web/20161223052210/http://www.ena.com.tr/Wind90.pdf Clark, Nolan "Variable Stroke Pumping for Mechanical Windmills", 1990, AWEA Proceedings]</ref>\n\n \nA piston pump has a very light suction phase, but the upstroke is heavy and puts a big backtorque on a starting rotor when the crank is horizontal and ascending. A counterweight on the crank up in the tower and yawing with the wind direction can at least spread the torque to the crank descent.\n\n \n[[File:Windmill-patent-drawing-from-1889-vintage-aged.jpg|thumb|left|Windmill-patent-drawing-from-1889-vintage-aged]][[File:Aldrich-windmill-patent-drawing-from-1889-blue-ink-aged-pixel.jpg|thumb|Aldrich-windmill-patent-drawing-from-1889]]\n\nAlthough multi-bladed windpumps are based on proven technology and are widely used, they have the fundamental problems mentioned above and need a practical variable stroke mechanism .\n\n Between 1988 and 1990, a variable stroke windpump was tested at the USDA-Agriculture Research Center-Texas, based on two patented designs (Don E. Avery Patent #4.392.785, 1983 and Elmo G. Harris Patent #617.877, 1899).<ref name="ena.com.tr"/> Control systems of the variable stroke wind pumps were mechanical and hydraulic; however, those experiments did not attract the attention of any windpump manufacturer. After experiments with this variable stroke windpump, research focused on wind-electric water pumping systems; no commercial variable stroke windpump exists yet.\n\n \nFluttering windpumps have been developed in Canada with a  pump stroke varying strongly with amplitude to absorb all the variable power in the wind and to stop the uniblade from swinging too far beyond horizontal from its vertical mean position. They are much lighter and use less material than multiblade windpumps and can pump effectively in lighter wind regimes.<ref>http://www.econologica.org</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211205/6zIj7LCtX0U Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20150607101812/https://www.youtube.com/watch?v=6zIj7LCtX0U Wayback Machine]{{cbignore}}: {{cite web| url = https://www.youtube.com/watch?v=6zIj7LCtX0U| title = WING'D MILLS 2013: FLO'Pump and FLUTTER WELL Pump | website=[[YouTube]]}}{{cbignore}}</ref>\n\n A Turkish engineer re-designed the variable stroke windpump technology by using modern electronic control equipment. Research began in 2004, with governmental R&D support. The first commercial new generation variable stroke wind pumps have been designed after ten years of R&D. The 30 kW variable stroke windpump design includes a Darrieus-type modern wind rotor, counterbalance and regenerative brake technology.<ref>[http://www.ena.com.tr/english.htm ENA Yelkapan Technologies Ltd.]</ref>\n\n Using a vertical axis wind turbine, the redirection of the turbine torque from horizontal to the vertical axis can be solved, thus creating a basic shaft connection between the turbine and the pump.<ref>[https://www.osti.gov/biblio/7101869-darrieus-wind-turbine-pump-performance-low-lift-irrigation-pumping-final-report Hagen, L. J., and Sharif, M., 1981, \u201cDarrieus Wind Turbine and Pump Performance for Low-Lift Irrigation Pumping,\u201d U.S. Department of Agriculture, Manhattan, KS, Report No. DOE/ARS-3707-20741/81/1.]</ref> The direct connection can produce a more efficient wind-pump. for example, Combining the VAWP system with a high-pressure (HP-VAWP) drip irrigation system can lead, with proper optimization, to two to three times higher efficiency than traditional windpumps.<ref>[https://asmedigitalcollection.asme.org/fluidsengineering/article-abstract/143/5/051204/1095494/High-Pressure-Vertical-Axis-Wind-Pump?redirectedFrom=fulltext Keisar, D., Eilan, B., and Greenblatt, D. (February 8, 2021). "High Pressure Vertical Axis Wind Pump." ASME. J. Fluids Eng. May 2021; 143(5): 051204. https://doi.org/10.1115/1.4049692]</ref>\n\n \n {{Main article|tjasker}}\n[[File:Tjasker Sanpoel 04.JPG|thumb|The ''tjasker'']]\nIn the [[Netherlands]], the ''tjasker'' is a drainage mill with [[windmill sail#Common sails|common sails]] connected to an [[Archimedean screw]]. This is used for pumping water in areas where only a small lift is required. The windshaft sits on a tripod which allows it to pivot. The Archimedean screw lifts water into a collecting ring, where it is drawn off into a ditch at a higher level, thus draining the land.<ref name=Tjasker>{{cite web|url=http://odur.let.rug.nl/polders/boekje/types.htm|title=The types of windmills|publisher=Odur|access-date=2008-05-24}}</ref>\n\n In Thailand, windpumps are traditionally built on Chinese windpump designs. These pumps are constructed from wire-braced bamboo poles carrying fabric or bamboo-mat sails; a paddle pump or [[waterladder pump]] is fixed to a Thai bladed rotor. They are mainly used in [[Salt pan (evaporation)|salt pans]] where the water lift required is typically less than one meter.<ref>{{cite journal|last=Smulders|first=P.T.|date=January 1996|title=Wind water pumping: the forgotten option|journal=[[Energy for Sustainable Development]]|volume=11|issue=5|url=http://www.energieautark.at/cms/dmdocuments/WindwaterpumpingAfrica.pdf}}</ref>\n\n *''[[:nl:Tjasker|Tjasker]]'' on Dutch Wikipedia\n*[[Wind turbine]]\n*[[Blade solidity]]\n*[[Coil pump]], another frequently used pump<ref>[http://blog.modernmechanix.com/2007/07/27/chinese-windmill-waters-farm/ Coil pump frequently used for windpump construction]</ref>\n*[[Loeriesfontein, Northern Cape]], where there is a museum dedicated to water-pumping windmills\n*[[Aermotor Windmill Company]], an American windpump manufacturer\n\n {{Reflist|refs=\n<ref name=isis>{{cite journal|title= Simon Stevin of Bruges (1548-1620)|author=Sarton, George| journal=Isis| volume=21| issue=2| pages=241\u2013303 | year=1934|doi= 10.1086/346851|s2cid=144054163}}</ref>\n|2}}\n\n {{Commons category|Wind pumps}}\n*[http://picasaweb.google.com/andy.bytheway/RestorationOfASouthAfricanWindmill# A detailed photographic record of the restoration of an 8' Stewarts & Lloyds windpump in South Africa]\n*[http://www.ironmanwindmill.com/windmill-history.htm History of the Water Pumping Windmill in America.]\n*[http://www.ironmanwindmill.com/how-windmills-work.htm How Water Pumping Windmills work.]\n\n{{Authority control}}", "Windpump --- Introduction ---|Worldwide use": "[[File:Wicken Fen Windpump.jpg|thumb|A working wooden windpump on [[The Fens]] in [[Cambridgeshire]], UK]]\nThe [[Netherlands]] is well known for its windmills. Most of these iconic structures situated along the edge of [[polders]] are actually windpumps, designed to drain the land. These are particularly important as much of the country lies below [[sea level]].\n\nIn the UK, the term ''windpump'' is rarely used, and they are better known as ''drainage windmills''. Many of these were built in [[The Broads]] and [[The Fens]] of [[East Anglia]] for the draining of land, but most of them have since been replaced by [[diesel fuel|diesel]] or electric powered pumps.<ref>{{cite book|url=https://books.google.com/books?id=K-JRAQAAIAAJ&pg=PA106|page=106|title=The Norfolk Broads: A Landscape History|last=Williamson|first=Tom|publisher=Manchester University Press|year=1997|isbn=9780719048005}}</ref> Many of the original windmills still stand in a derelict state although some have been restored.<sup>[needs citation]</sup>\n\nWindpumps are used extensively in [[Southern Africa]], Australia, and on farms and ranches in the central plains and Southwest of the United States. In South Africa and Namibia thousands of windpumps are still operating. These are mostly used to provide water for human use as well as drinking water for large sheep stocks.\n\n[[Kenya]] has also benefited from the African development of windpump technologies. At the end of the 1970s, the UK [[NGO]] [[Intermediate Technology Development Group]] provided engineering support to the Kenyan company Bobs Harries Engineering Ltd for the development of the Kijito windpumps. Bobs Harries Engineering Ltd is still manufacturing the Kijito windpumps, and more than 300 of them are operating in the whole of [[East Africa]].{{citation needed|date=August 2021}}\n\nIn many parts of the world, a [[rope pump]] is being used in conjunction with wind turbines. This easy-to- construct pump works by pulling a knotted rope through a pipe (usually a simple PVC pipe) causing the water to be pulled up into the pipe. This type of pump has become common in [[Nicaragua]] and other places.{{citation needed|date=August 2021}}"}},
{"article_title": "Devon Rex", "pageid": "146038", "revid": "1055504510", "timestamp": "2021-11-16T07:16:05Z", "history_paths": [["Devon Rex --- Introduction ---", "Breed history"]], "categories": ["science and technology in devon", "rex cat breeds", "cat breeds originating in england", "cat breeds"], "heading_tree": {"Devon Rex --- Introduction ---": {"Breed history": {}, "Appearance": {"Hair": {}, "Other characteristics": {}}, "Personality": {}, "Gallery": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Devon Rex --- Introduction ---|Breed history": "The Devon Rex is a [[cat breeds|breed]] of [[cat]] with a curly, very soft short coat similar to that of the [[Cornish Rex]]. They are often thought of as one of the most hypoallergenic cats available because of their type of coat. However, they are technically not hypoallergenic.\n\nThe first Devon was discovered by Beryl Cox<ref name="cfa">{{Cite web|url=http://www.cfa.org/Breeds/BreedsCJ/DevonRex.aspx|title=Breed Profile: The Devon Rex|website=cfa.org|access-date=2017-11-16}}</ref> in [[Buckfastleigh]], [[Devon]], UK, in 1959.<ref name="cattime">{{Cite web|url=http://cattime.com/cat-breeds/devon-rex-cats#/slide/1|title=Devon Rex|website=cattime.com|access-date=2017-11-16}}</ref> The breed was initially thought to be linked with the Cornish Rex; however, test mating proved otherwise.<ref name="cattime"/>"}},
{"article_title": "Steamship", "pageid": "146635", "revid": "1053913858", "timestamp": "2021-11-06T21:18:26Z", "history_paths": [["Steamship --- Introduction ---", "History"]], "categories": ["steamships", "steam engines", "steam engine technology"], "heading_tree": {"Steamship --- Introduction ---": {"History": {}, "Screw-propeller steamers": {}, "Name prefix": {}, "First ocean-going steamships": {}, "Long-distance commercial steamships": {}, "Triple expansion engines": {}, "Era of the ocean liner": {}, "Decline of the steamship": {}, "1970\u2013present day": {}, "See also": {}, "Notes": {}, "References": {}, "Bibliography": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Steamship --- Introduction ---|History": "The steamship was preceded by smaller vessels, called [[steamboat]]s, conceived in the first half of the 18th century, with the first working steamboat and [[paddle steamer]], the [[Pyroscaphe]], from 1783. Once the technology of steam was mastered at this level, steam engines were mounted on larger, and eventually, ocean-going vessels. Becoming reliable, and propelled by screw rather than paddlewheels, the technology changed the design of ships for faster, more economic propulsion.\n\n[[Paddle]]wheels as the main motive source became standard on these early vessels. It was an effective means of propulsion under ideal conditions but otherwise had serious drawbacks. The paddle-wheel performed best when it operated at a certain depth, however when the depth of the ship changed from added weight it further submerged the paddle wheel causing a substantial decrease in performance.<ref>[[#Carlton2012|Carlton, 2012]] p.23</ref>\n\nWithin a few decades of the development of the river and canal steamboat, the first steamships began to cross the [[Atlantic Ocean]]. The first sea-going steamboat was Richard Wright's first steamboat ''Experiment'', an ex-French [[lugger]]; she steamed from [[Leeds]] to [[Great Yarmouth|Yarmouth]] in July 1813.<ref>{{Citation | first = R | last = Malster | title = Wherries & Waterways | place = Lavenham | year = 1971 | page = 61}}.</ref><ref name="google">{{cite book|title=DNB|author=Stephen, L.|date=1894|publisher=Smith, Elder, & Company|url=https://books.google.com/books?id=puApAAAAYAAJ&pg=PA399|page=399|access-date=2017-12-28}}</ref><!---could use better citation to prove that there was a canal from Leeds to Yarmouth, but that seems to be the intent of all statements on the subject-->\n\nThe first iron steamship to go to sea was the 116-ton ''[[Aaron Manby]]'', built in 1821 by [[Aaron Manby (ironmaster)|Aaron Manby]] at the [[Horseley Ironworks]], and became the first iron-built vessel to put to sea when she crossed the [[English Channel]] in 1822, arriving in Paris on 22 June.<ref name="artistaswitness">{{cite web|url=http://www.artistaswitness.com/Steamships/steamships_dn_07.htm|website=artistaswitness.com|title=Steamships/steamships_dn_07|access-date=2017-12-28}}</ref> She carried passengers and freight to Paris in 1822 at an average speed of 8 knots (9 mph, 14 km/h).\n\n[[File:Great Western maiden voyage.jpg|thumb|The side-wheel paddle steamer {{SS|Great Western}}, the first purpose-built transatlantic steamship, on its maiden voyage in 1838|alt=]]\n\nThe American ship {{SS|Savannah}} first crossed the Atlantic Ocean arriving in Liverpool, England, on June 20, 1819, although most of the voyage was actually made under sail. The first ship to make the transatlantic trip substantially under steam power may have been the British-built Dutch-owned ''Cura\u00e7ao'', a wooden 438-ton vessel built in [[Dover]] and powered by two 50 hp engines, which crossed from [[Hellevoetsluis]], near [[Rotterdam]] on 26 April 1827 to [[Paramaribo]], [[Surinam]] on 24 May, spending 11 days under steam on the way out and more on the return. Another claimant is the Canadian ship {{SS|Royal William}} in 1833.<ref>{{cite book |title=Steam Navigation: And Its Relation to the Commerce of Canada and the United |publisher=W. Briggs |first=James |last= Croil |page=[https://archive.org/details/steamnavigation03croigoog/page/n58 54] |year=1898 |url=https://archive.org/details/steamnavigation03croigoog}}</ref>\n\nThe first steamship purpose-built for regularly scheduled trans-Atlantic crossings was the British side-wheel paddle steamer {{SS|Great Western}} built by  [[Isambard Kingdom Brunel]] in 1838, which inaugurated the era of the trans-Atlantic [[ocean liner]].\n\nThe {{SS|Archimedes}}, built in Britain in 1839 by  [[Francis Pettit Smith]], was the world's first [[propeller#History of ship and submarine screw propellers|screw propeller]]-driven steamship{{efn|The emphasis here is on ''ship''. There were a number of successful screw propeller driven vessels prior to ''Archimedes'', including Smith's own ''Francis Smith'' and Ericsson's ''Francis B. Ogden'' and ''Robert F. Stockton''. However, these vessels were ''boats''\u2014designed for service on inland waterways\u2014as opposed to ''ships'', built for seagoing service.}} for open water seagoing. She had considerable influence on ship development, encouraging the adoption of screw propulsion by the [[Royal Navy]], in addition to her influence on commercial vessels. The first screw-driven propeller steamship  introduced in America was on a ship built by [[Thomas Clyde (businessman)|Thomas Clyde]] in 1844 and many more ships and routes followed."}},
{"article_title": "Digital Video Broadcasting", "pageid": "146977", "revid": "1057558453", "timestamp": "2021-11-28T09:40:38Z", "history_paths": [["Digital Video Broadcasting --- Introduction ---", "Adoption"]], "categories": ["digital video broadcasting", "digital broadcasting", "digital television", "high-definition television", "mpeg", "open standards", "television technology", "television transmission standards"], "heading_tree": {"Digital Video Broadcasting --- Introduction ---": {"Transmission": {}, "Content": {}, "Encryption and metadata": {}, "Software platform": {}, "Return channel": {}, "Adoption": {"Africa": {"Kenya": {}, "Madagascar": {}, "South Africa": {}}, "Asia": {"Hong Kong": {}, "Iran": {}, "Israel": {}, "Japan": {}, "Malaysia": {}, "Philippines": {}, "Taiwan": {}}, "Europe": {"Cyprus": {}, "Denmark": {}, "Finland": {}, "Italy": {}, "Netherlands": {}, "Norway": {}, "Poland": {}, "Portugal": {}, "Romania": {}, "Russia": {}, "United Kingdom": {}}, "North America": {}, "Oceania": {"Australia": {}, "New Zealand": {}}, "South America": {"Colombia": {}}}, "DVB compliant products": {}, "Related standards": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Digital Video Broadcasting --- Introduction ---|Adoption": "[[Image:Digital broadcast standards.svg|thumb|400px|right|DTT broadcasting systems.]]\nDVB-S and DVB-C were ratified in 1994. DVB-T was ratified in early 1997. The first commercial DVB-T broadcasts were performed by the [[United Kingdom]]'s [[Digital TV Group]] in late 1998. In 2003 [[Berlin]], [[Germany]] was the first area to completely stop broadcasting analog TV signals. Most European countries are fully covered by digital television and many have switched off [[PAL]]/[[SECAM]] services.\n\nIn [[Europe]], as well as in [[Australia]], [[South Africa]] and [[India]], DVB is used throughout. This also holds true for cable and satellite in most [[Asia]]n, [[Africa]]n and many [[South America]]n countries. Many of these have not yet selected a format for digital terrestrial broadcasts (DTTV) and a few ([[Canada]], [[El Salvador]], [[Honduras]], [[Mexico]], [[South Korea]] and the [[United States]]) have chosen ATSC instead of DVB-T.\n\n \n DVB-T broadcasts were launched by the [[President of Kenya]], [[Mwai Kibaki]] on 9 December 2009. Broadcasts are using [[H.264/MPEG-4 AVC|H.264]], with the [[University of Nairobi]] supplying the decoders. [[Kenya]] has also been broadcasting DVB-H since July 2009, available on selected [[Nokia]] and [[ZTE]] handsets on the [[Safaricom]] and other GSM networks.<ref>{{cite web |url=http://www.nation.co.ke/News/-/1056/819994/-/vnlh64/-/ |title=Digital TV a reality in Kenya |publisher=Nation Media |access-date=2009-12-09}}</ref>\n\n Since 2011, the pay TV operator Blueline<ref>{{cite web|url=http://www.blueline.mg|title=Blueline Madagascar|website=www.blueline.mg|access-date=1 April 2018}}</ref> launched a DVB-T service branded BluelineTV.<ref>[http://www.blueline.mg/tv BluelineTV]</ref> It supplies both smart cards and set-top-boxes.\n\n Since 1995, the pay TV operator [[DStv]] used the DVB-S standard to broadcast its services. In 2010 it started a DVB over IP service, and in 2011 it started DStv mobile using the DVB-H standard.<ref>http://www.multichoice.co.za/multichoice/content/en/page44122</ref>\n\nIn late 2010, the South African cabinet endorsed a decision by a [[Southern African Development Community]] (SADC) task team to adopt the DVB-T2 standard.<ref>{{cite web |url=http://www.fin24.com/Economy/SA-to-adopt-European-TV-standard-report-20110104 |title=SA to adopt European TV standard: report |publisher=24.com |access-date=2011-01-18}}</ref>\n\n In Asia several Standards are under implementation\n\n In [[Hong Kong]], several cable TV operators such as [[TVB Pay Vision]] and [[Cable TV Hong Kong|Cable TV]] have already started using DVB-S or DVB-C. The government however has adopted the [[DMB-T/H]] standard, developed in [[mainland China]], for its digital terrestrial broadcasting services which has started since 31 December 2007.<ref>{{cite web|url=http://www.digitaltv.gov.hk/general/news_26112007.htm|title=Digital TV|website=www.digitaltv.gov.hk|access-date=1 April 2018|archive-url=https://web.archive.org/web/20110721092023/http://www.digitaltv.gov.hk/general/news_26112007.htm|archive-date=21 July 2011|url-status=dead}}</ref>\n\n On 17 March 2009, DVB-H and DVB-T H.264/AAC broadcasting started in [[Tehran]].\nDVB-T broadcasting now available in other cities like: Isfahan, Mashhad, Shiraz, Qom, [[Tabriz]] and Rasht.\n\n DVB-T broadcasts using [[H.264/MPEG-4 AVC|H.264]] commenced in [[Israel]] on 1 June 2009 with the broadcast trial and the full broadcast began on 2 August 2009. Analog broadcasts were originally planned to end in 18 months after the launch, but analog broadcasts were switched off on 31 March 2011 instead.\n\nDuring 2010, DVB-T broadcasts have become widely available in most of Israel and an EPG was added to the broadcasts.<ref>{{cite web|url=http://www.dvb.org/about_dvb/dvb_worldwide/israel/index.xml|title=About - DVB|website=www.dvb.org|access-date=1 April 2018}}</ref>\n\n With the exception of [[SKY PerfecTV!]], [[Japan]] uses different formats in all areas ([[Integrated Services Digital Broadcasting|ISDB]]), which are however quite similar to their DVB counterparts. SkyPerfect is a satellite provider using DVB on its 124 and 128 degrees east satellites. Its satellite at 110 degrees east does not use DVB, however.\n\n In [[Malaysia]], a new pay television station [[MiTV]] began service in September 2005 using [[DVB-IPTV]] technology while lone satellite programming provider [[Astro (satellite TV)|ASTRO]] has been transmitting in DVB-S since its inception in 1996. Free-to-air DVB-T trials began in late 2006 with a simulcast of both TV1 and TV2 plus a new channel called RTM3/RTMi. In April 2007, RTM announced that the outcome of the test was favourable and that it expected DVB-T to go public by the end of 2007. However, the system did not go public as planned. As of 2008, the trial digital line-up has expanded to include a music television channel called [[Muzik Aktif]], and a sports channel called Arena, with a news channel called Berita Aktif planned for inclusion in the extended trials soon. Also, high definition trials were performed during the Beijing Olympics and the outcome was also favourable. It was announced that the system would go public in 2009.\n\nIn 2009, MiTV closed down, changed its name to U-Television and announced that it was changing to scrambled DVB-T upon relaunch instead of the [[DVB-IPTV]] system used prior to shutting down. However, RTM's digital network again did not go public, although around this time TVs that are first-generation DVB-T capable went on sale. The government has since announced that they will be deploying DVB-T2 instead in stages starting in mid-2015 and analog shutoff has been delayed to April 2019.\n\n In the [[Philippines]], [[DVB-S]] and [[DVB-S2]] are the two broadcast standards currently used by satellite companies, while [[DVB-C]] is also used by some cable companies. The government adopted [[DVB-T]] in November 2006 for digital terrestrial broadcasting but a year later, it considered other standards to replace DVB-T. The country has chosen the [[ISDB-T]] system instead of [[DVB-T]].\n\n {{Update|section|date=May 2016}}\nIn [[Taiwan]], some digital cable television systems use DVB-C, though most customers still use analog NTSC cable television. The government planned adopting ATSC or the Japanese ISDB-T standard as NTSC's replacement. However, the country has chosen the European DVB-T system instead. Public Television Service (PTS) and Formosan TV now provided high definition television.  The former has a channel called HiHD; the latter uses its HD channel for broadcasting MLB baseball.\n\n {{Update|European countries that use DVB but are not in this list|January 1018|date=January 2018}}\n\n [[Cyprus]] uses DVB-T with MPEG-4 encoding. Analog transmission stopped on 1 July 2011 for all channels except [[CyBC|CyBC 1]].\n\n In [[Denmark]], DVB-T replaced the analog transmission system for TV on 1 November 2009. Danish national digital TV transmission has been outsourced to the company Boxer TV A/S,<ref>{{cite web|url=http://www.boxertv.dk|title=Fleksible tv-pakker og bredb\u00e5nd hos Boxer - Tv-udbyder med valgfrihed|website=www.boxertv.dk|access-date=1 April 2018}}</ref> acting as gatekeeper organization for terrestrial TV transmission in Denmark.<ref>{{cite web|url=http://www.kum.dk/graphics/kum/downloads/Pressemeddelelser/Pressemeddelelse+fra+N%25E6vnet+UK.pdf|title=Kulturministeriets hjemmeside|website=www.kum.dk|access-date=1 April 2018}}</ref><ref>{{cite web|url=http://www.kum.dk/sw69161.asp|title=Kulturministeriets hjemmeside|website=www.kum.dk|access-date=1 April 2018|archive-url=https://web.archive.org/web/20091008071354/http://www.kum.dk/sw69161.asp|archive-date=8 October 2009|url-status=dead}}</ref> However, there are still several free channels from [[DR (broadcaster)|DR]].\n\n {{See also|Television in Finland}}\nDVB-T transmissions were launched on 21 August 2001. The analogue networks continued alongside the digital ones until 1 September 2007, when they were shut down nationwide. Before the analogue switchoff, the terrestrial network had three multiplexes: MUX A, MUX B and MUX C. MUX A contained the channels of the public broadcaster [[Yleisradio]] and MUX B was shared between the two commercial broadcasters: [[MTV3]] and [[Nelonen]]. MUX C contained channels of various other broadcasters. After the analogue closedown, a fourth multiplex named MUX E was launched. All of the [[Yleisradio]] (YLE) channels are broadcast free-to-air, likewise a handful of commercial ones including [[MTV3]], [[Nelonen]], [[Subtv]], [[Jim (TV channel)|Jim]], [[Nelonen Sport]], [[Liv (TV channel)|Liv]], [[FOX (Finland)|FOX]], [[TV Viisi|TV5]] [[Finland]], [[AVA (TV channel)|AVA]] and [[The Voice TV Finland|Kutonen]]. There are also several pay channels sold by [[PlusTV]].\n\n {{See also|Television in Italy}}\nIn Italy, DVB-S started in 1996 and the final analogue broadcasts were terminated in 2005. The switch-off from analogue terrestrial network to DVB-T started on 15 October 2008. Analogue broadcast was ended on 4 July 2012 after nearly four years of transition in phases.\n\n In the [[Netherlands]], DVB-S broadcasting started on 1 July 1996, satellite provider MultiChoice (now [[CanalDigitaal]]) switched off the analogue service shortly after on 18 August 1996. DVB-T broadcasting started April 2003, and terrestrial analog broadcasting was switched off December 2006. It was initially marketed by [[Digitenne]] but later by [[KPN]]. Multiplex 1 contains the [[NPO 1]], [[NPO 2]] and [[NPO 3]] national TV channels, and a regional channel. Multiplexes 2~5 have the other encrypted commercial and international channels. Multiplex 1 also broadcasts the radio channels Radio 1, Radio 2, 3 FM, Radio 4, Radio 5, Radio 6, Concertzender, FunX and also a regional channel. As of June 2011, the Dutch DVB-T service had 29 TV channels and 20 radio channels (including free to air channels). DVB-T2 will be introduced during 2019/2020.\n\n In [[Norway]], DVB-T broadcasting is marketed under RiksTV (encrypted pay channels) and [[NRK]] (unencrypted public channels). DVB-T broadcasting via the terrestrial network began in November 2007, and has subsequently been rolled out one part of the country at a time. The Norwegian implementation of DVB-T is different from most others, as it uses [[H.264]] with [[HE-AAC]] audio encoding, while most other countries have adapted the less recent [[MPEG-2]] standard. Notably most DVB software for PC has problems with this, though in late 2007 compatible software was released, like [[DVBViewer]] using the [[Advanced Audio Coding#FAAC and FAAD2|libfaad2]] library. [[Sony]] has released several HDTVs (Bravia W3000, X3000, X3500, E4000, V4500, W4000, W4500, X4500) that support Norway's DVB-T implementation without use of a separate [[set-top box]], and Sagem ITD91 HD, Grundig DTR 8720 STBs are others.\n\n Currently, [[Poland]] uses the DVB-T standard with MPEG-4 encoding. Analogue broadcast switch-off started on 7 November 2012 and was completed on 23 July 2013.<ref>{{cite web |url=https://mac.gov.pl/naziemna-telewizja-cyfrowa/ |title=General information about the digital broadcasting system in Poland |publisher=Ministry of Administration and Digitalization of Poland |access-date=2013-08-13}}</ref>\n\n [[Portugal]] follows the DVB-T implementation, using H.264 with AAC audio encoding. It has been live since 29 April 2009 and the switch-off date for all analog signals was on 26 April 2012.\n\n [[Romania]] started digital terrestrial broadcasting in 2005 but it was virtually unknown by many people in Romania due to the lack of content, cable TV and satellite TV being far more popular, however it was the first platform to deliver HD content. Today, Romania is using DVB-T2 as terrestrial standard,  but also DVB-S/S2, and DVB-C which is extremely popular. The only analogue broadcast remains on cable. Romania adopted the DVB-T2 standard in 2016 after a series of tests with mpeg2, mpeg4 on DVB-T, and has today fully implemented DVB-T2. DVB-C, which was introduced in late 2005, still remains with mpeg2 on SD content and mpeg4 on HD content. DVB-S (introduced in 2004 focus sat being the first such platform) is used in basic packages with standard definition content, while DVB-S2 set top boxes are provided for both SD and HD content.\n\n Fully switched to digital in 2019, [[Russia]] uses the DVB-T2 standard for broadcasting 2 channel packs with about ten main national radio and TV channels ([[Channel One (Russia)|Channel One]], [[Rossiya 1]]/2/K/24, [[NTV (Russia)|NTV]], [[Radio Mayak]], [[Radio Rossii]] etc.\n\n {{See also|Digital terrestrial television in the United Kingdom}}\nIn the UK DVB-T has been adopted for broadcast of standard definition terrestrial programming, as well as a single DVB-T2 multiplex for high-definition programming. The UK terminated all analogue terrestrial broadcasts by the end of 2012. The vast majority of channels are available [[free-to-air]] through the [[Freeview (UK)|Freeview]] service. DVB-T was also used for the now-defunct [[ITV Digital|ONDigital/ITV Digital]] and [[Top Up TV]] service.\n\nAll satellite programming (some of which is available free-to-air via [[Freesat]] or [[free-to-view]] via [[Freesat from Sky]]; the remainder requires a subscription to [[Sky (UK and Ireland)|Sky]]), is broadcast using either DVB-S or DVB-S2.\n\nSubscription-based cable television from [[Virgin Media]] uses DVB-C.\n\n In [[North America]], [[DVB-S]] is often used in encoding and [[video compression]] of digital satellite communications alongside [[Hughes DSS]]. Unlike [[Motorola]]'s [[DigiCipher 2]] standard, DVB has a wider adoption in terms of the number of manufacturers of receivers. Terrestrial digital television broadcasts in Canada, Mexico, El Salvador, Honduras, and the United States use ATSC encoding with [[8VSB]] modulation instead of DVB-T with [[COFDM]].  Television newsgathering links from mobile vans to central receive points (often on mountaintops or tall buildings) use DVB-T with COFDM in the 2 GHz frequency band.\n\n  In [[Australia]], DVB broadcasting is marketed under the [[Freeview (Australia)|Freeview]] brand name, and more recently 'Freeview Plus', denoting the integration of online [[HbbTV]] and EPG in certain DVB devices. Regular broadcasts began in January 2001 using MPEG 2 video and MPEG 1 audio in SD and HD.\n\nChanges to broadcasting rules have enabled broadcasters to offer multi-channeling, prompting broadcasters to use H.264 video with MPEG 1 or AAC audio encoding for some secondary channels.\n\nSpecifications for HD channels now differ depending on the broadcaster. ABC, Nine and Ten use 1920x1080i MPEG 4 video with [[Dolby Digital]] audio. Seven and SBS use 1440x1080i MPEG 2 video with Dolby Digital and MPEG 1 audio respectively.<ref>{{cite web|url=http://about.abc.net.au/press-releases/abc-is-changing-to-hd/ |title=ABC HD is now live |publisher=Australian Broadcasting Corporation |access-date=27 December 2016}}</ref>\n\n In [[New Zealand]], DVB broadcasting is marketed under the [[Freeview (New Zealand)|Freeview]] brand name. SD [[MPEG-2]] DVB-S broadcasts via satellite began on 2 May 2007 and DVB-T (terrestrial) broadcasts began April 2008 broadcasting in HD H.264 video with HE-AAC audio.\n\n \n Since 2008, [[Colombia]] has adopted as a public policy the decision to migrate from the analog television implemented in 1954 to [[Digital terrestrial television|Digital Terrestrial Television]] ([[DVB-T2]]). This measure allows the viewers access to the open television ([[Terrestrial television|OTA]]) of public and private channels, with video quality in [[High-definition television|HD]]. As planned, analogue television broadcasts will end in 2021."}},
{"article_title": "HIV vaccine development", "pageid": "147473", "revid": "1062163493", "timestamp": "2021-12-26T18:45:07Z", "history_paths": [["HIV vaccine development --- Introduction ---"], ["HIV vaccine development --- Introduction ---", "Difficulties in development"], ["HIV vaccine development --- Introduction ---", "Clinical trials"]], "categories": ["hiv vaccine research", "prevention of hiv/aids", "hypothetical technology"], "heading_tree": {"HIV vaccine development --- Introduction ---": {"Difficulties in development": {"HIV structure": {}, "Animal model": {}}, "Clinical trials": {"Phase I": {}, "Phase II": {}, "Phase III": {}}, "Economics": {}, "Classification of possible vaccines": {"Filtering virions from blood (Stage I)": {}, "Approaches to catching the virion (Stage I-III, VI, VII)": {}, "Approaches to destroying or damaging the virion or its parts (Stage I-VII)": {}, "Blocking replication (Stage V)": {}, "Biological, chemical or physical approaches to inhibit the process of phases": {}, "Inhibiting the functionality of infected cells (Stage VI-VII)": {}}, "Future work": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"HIV vaccine development --- Introduction ---": "{{Short description|In-progress vaccinations that may prevent or treat HIV infections}}\n{{Update|type=|date=November 2021|reason=}}\n[[File:Various approaches for HIV vaccine development.jpg|thumb|right|Various approaches for HIV vaccine development]]\nA '''HIV vaccine''' is a potential vaccine that could be either a preventive [[vaccine]] or a therapeutic vaccine, which means it would either protect individuals from being infected with [[HIV]] or treat HIV-infected individuals. \n\nIt is thought that a HIV vaccine could either induce an immune response against HIV (active vaccination approach) or consist of preformed antibodies against HIV (passive vaccination approach).<ref>{{cite journal | vauthors = Gray GE, Laher F, Lazarus E, Ensoli B, Corey L | title = Approaches to preventative and therapeutic HIV vaccines | journal = Current Opinion in Virology | volume = 17 | pages = 104\u2013109 | date = April 2016 | pmid = 26985884 | pmc = 5020417 | doi = 10.1016/j.coviro.2016.02.010 }}</ref>\n\nTwo active vaccine regimens, studied in the [[RV 144]] and Imbokodo trials, showed they can prevent HIV in some individuals.\n\nHowever, the protection was in relatively few individuals, and was not long lasting. For these reasons, no HIV vaccines have been licensed for the market yet.\n\n In 1984, after it was confirmed that HIV caused AIDS, the United States [[Health and Human Services Secretary]] [[Margaret Heckler]] declared that a [[vaccine]] would be available within two years.<ref>{{cite book | last = Shilts | first = Randy | year = 1987 | title = And the Band Played On: Politics, People, and the AIDS Epidemic | edition = 2007 | publisher = St. Martin's Press | isbn = 978-0-312-24135-3 | page = [https://archive.org/details/andbandplayedonp00shil_0/page/451 451] | url-access = registration | url = https://archive.org/details/andbandplayedonp00shil_0/page/451 }}</ref> However, priming the [[adaptive immunity|adaptive immune]] system to recognize the [[viral envelope]] proteins did not prevent HIV acquisition. \n\nMany factors make the development of an HIV vaccine different from other classic vaccines:<ref>{{cite journal | vauthors = Fauci AS | year = 1996 | title = An HIV vaccine: breaking the paradigms | journal = Proc. Am. Assoc. Phys. | volume = 108 | issue = 1| pages = 6\u201313 | pmid = 8834058 }}</ref>\n* Classic vaccines mimic natural immunity against reinfection as seen in individuals recovered from infection; there are almost no recovered AIDS patients.{{Citation needed|date=January 2019}}\n* Most vaccines protect against disease, not against infection; HIV infection may remain latent for long periods before causing AIDS.\n* Most effective vaccines are whole-killed or live-attenuated organisms; killed HIV-1 does not retain antigenicity and the use of a live retrovirus vaccine raises safety issues.\n\n [[File:HIV structure cycle zh.png|thumb|HIV structure cycle]]\nThe [[epitope]]s of the viral envelope are more variable than those of many other viruses. Furthermore, the functionally important epitopes of the [[gp120]] protein are masked by [[glycosylation]], [[trimerisation]] and receptor-induced conformational changes making it difficult to block with neutralizing antibodies.\n\nThe ineffectiveness of previously developed vaccines primarily stems from two related factors:\n* First, HIV is highly mutable. Because of the virus's ability to rapidly respond to selective pressures imposed by the immune system, the population of virus in an infected individual typically evolves so that it can evade the two major arms of the adaptive immune system; humoral ([[antibody]]-mediated) and cellular (mediated by [[T cells]]) immunity.\n* Second, HIV isolates are themselves highly variable. HIV can be categorized into multiple subtypes with a high degree of genetic divergence. Therefore, the immune responses raised by any vaccine need to be broad enough to account for this variability. Any vaccine that lacks this breadth is unlikely to be effective.\n\nThe difficulties in stimulating a reliable [[antibody]] response has led to the attempts to develop a vaccine that stimulates a response by [[cytotoxic T-lymphocyte]]s.<ref name="pmid17502236">{{cite journal | vauthors = Kim D, Elizaga M, Duerr A | title = HIV vaccine efficacy trials: towards the future of HIV prevention | journal = Infectious Disease Clinics of North America | volume = 21 | issue = 1 | pages = 201\u201317, x | date = March 2007 | pmid = 17502236 | doi = 10.1016/j.idc.2007.01.006 }}</ref><ref name="pmid18425263">{{cite journal | vauthors = Watkins DI | title = The hope for an HIV vaccine based on induction of CD8+ T lymphocytes--a review | journal = Mem\u00f3rias do Instituto Oswaldo Cruz | volume = 103 | issue = 2 | pages = 119\u201329 | date = March 2008 | pmid = 18425263 | pmc = 2997999 | doi = 10.1590/S0074-02762008000200001 }}</ref>\n\nAnother response to the challenge has been to create a single peptide that contains the least variable components of all the known HIV strains.<ref name="pmid17912361">{{cite journal | vauthors = L\u00e9tourneau S, Im EJ, Mashishi T, Brereton C, Bridgeman A, Yang H, Dorrell L, Dong T, Korber B, McMichael AJ, Hanke T | title = Design and pre-clinical evaluation of a universal HIV-1 vaccine | journal = PLOS ONE | volume = 2 | issue = 10 | pages = e984 | date = October 2007 | pmid = 17912361 | pmc = 1991584 | doi = 10.1371/journal.pone.0000984 | editor1-last = Nixon | editor1-first = Douglas | bibcode = 2007PLoSO...2..984L | doi-access = free }}</ref>\n\n [[File:2006-12-09 Chipanzees D Bruyere.JPG|thumb| Young chimpanzees from [[Tchimpounga Sanctuary]] ([[Republic of the Congo]])]]\nThe typical [[animal model]] for vaccine research is the monkey, often the [[macaque]]. Monkeys can be infected with [[Simian immunodeficiency virus|SIV]] or the chimeric SHIV for research purposes. However, the well-proven route of trying to induce neutralizing antibodies by vaccination has stalled because of the great difficulty in stimulating antibodies that neutralise heterologous primary HIV isolates.<ref>{{cite journal | vauthors = Poignard P, Sabbe R, Picchio GR, Wang M, Gulizia RJ, Katinger H, Parren PW, Mosier DE, Burton DR | display-authors = 6 | title = Neutralizing antibodies have limited effects on the control of established HIV-1 infection in vivo | journal = Immunity | volume = 10 | issue = 4 | pages = 431\u20138 | date = April 1999 | pmid = 10229186 | doi = 10.1016/S1074-7613(00)80043-6 | doi-access = free }}</ref> Some vaccines based on the virus envelope have protected chimpanzees or macaques from homologous virus challenge,<ref>{{cite journal | vauthors = Berman PW, Gregory TJ, Riddle L, Nakamura GR, Champe MA, Porter JP, Wurm FM, Hershberg RD, Cobb EK, Eichberg JW | display-authors = 6 | title = Protection of chimpanzees from infection by HIV-1 after vaccination with recombinant glycoprotein gp120 but not gp160 | journal = Nature | volume = 345 | issue = 6276 | pages = 622\u20135 | date = June 1990 | pmid = 2190095 | doi = 10.1038/345622a0 | bibcode = 1990Natur.345..622B | s2cid = 4258128 }}</ref> but in clinical trials, humans who were immunised with similar constructs became infected after later exposure to HIV-1.<ref>{{cite journal | vauthors = Connor RI, Korber BT, Graham BS, Hahn BH, Ho DD, Walker BD, Neumann AU, Vermund SH, Mestecky J, Jackson S, Fenamore E, Cao Y, Gao F, Kalams S, Kunstman KJ, McDonald D, McWilliams N, Trkola A, Moore JP, Wolinsky SM | display-authors = 6 | title = Immunological and virological analyses of persons infected by human immunodeficiency virus type 1 while participating in trials of recombinant gp120 subunit vaccines | journal = Journal of Virology | volume = 72 | issue = 2 | pages = 1552\u201376 | date = February 1998 | pmid = 9445059 | pmc = 124637 | doi =  10.1128/JVI.72.2.1552-1576.1998}}</ref>\n\nThere are some differences between SIV and HIV that may introduce challenges in the use of an animal model. The animal model can be extremely useful but at times controversial.<ref>{{cite journal | vauthors = Morgan C, Marthas M, Miller C, Duerr A, Cheng-Mayer C, Desrosiers R, Flores J, Haigwood N, Hu SL, Johnson RP, Lifson J, Montefiori D, Moore J, Robert-Guroff M, Robinson H, Self S, Corey L | display-authors = 6 | title = The use of nonhuman primate models in HIV vaccine development | journal = PLOS Medicine | volume = 5 | issue = 8 | pages = e173 | date = August 2008 | pmid = 18700814 | pmc = 2504486 | doi = 10.1371/journal.pmed.0050173 | author-link8 = Nancy Haigwood }}</ref>\n\nThere is a new animal model strongly resembling that of HIV in humans. Generalized immune activation as a direct result of activated CD4+ T cell killing - performed in mice allows new ways of testing HIV behaviour.<ref>{{cite journal | vauthors = Marques R, Williams A, Eksmond U, Wullaert A, Killeen N, Pasparakis M, Kioussis D, Kassiotis G | display-authors = 6 | title = Generalized immune activation as a direct result of activated CD4+ T cell killing | journal = Journal of Biology | volume = 8 | issue = 10 | pages = 93 | year = 2009 | pmid = 19943952 | pmc = 2790834 | doi = 10.1186/jbiol194 }}</ref><ref>{{cite journal | vauthors = Vrisekoop N, Mandl JN, Germain RN | title = Life and death as a T lymphocyte: from immune protection to HIV pathogenesis | journal = Journal of Biology | volume = 8 | issue = 10 | pages = 91 | year = 2009 | pmid = 19951397 | pmc = 2790836 | doi = 10.1186/jbiol198 }}</ref>\n\n[[National Institute of Allergy and Infectious Diseases|NIAID]]-funded SIV research has shown that challenging monkeys with a [[cytomegalovirus]] (CMV)-based SIV vaccine results in containment of virus. Typically, virus replication and dissemination occurs within days after infection, whereas vaccine-induced T cell activation and recruitment to sites of viral replication take weeks. Researchers hypothesized that vaccines designed to maintain activated effector memory T cells might impair viral replication at its earliest stage.{{Citation needed|date=October 2012}}\n\n \nSeveral vaccine candidates are in varying phases of [[clinical trial]]s.\n\n Most initial approaches have focused on the [[HIV envelope]] protein. At least thirteen different [[gp120]] and [[gp160]] envelope candidates have been evaluated, in the US predominantly through the AIDS Vaccine Evaluation Group. Most research focused on gp120 rather than gp41/gp160, as the latter is generally more difficult to produce and did not initially offer any clear advantage over gp120 forms. Overall, they have been safe and immunogenic in diverse populations, have induced neutralizing antibody in nearly 100% recipients, but rarely induced [[Cytotoxic T cell|CD8+ cytotoxic T lymphocytes]] (CTL). Mammalian derived envelope preparations have been better inducers of neutralizing antibody than candidates produced in yeast and bacteria. Although the vaccination process involved many repeated "[[booster dose|booster]]" injections, it was challenging to induce and maintain the high anti-gp120 antibody [[titer]]s necessary to have any hope of neutralizing an HIV exposure.{{citation needed|date=January 2021}}\n\nThe availability of several recombinant [[canarypox]] [[Viral vector vaccine|vectors]] has provided interesting results that may prove to be generalizable to other [[viral vector]]s. Increasing the complexity of the canarypox vectors by including more genes/epitopes has increased the percent of volunteers that have detectable CTL to a greater extent than did increase the dose of the viral vector. CTLs from volunteers were able to kill [[PBMC|peripheral blood mononuclear cells]] infected with primary isolates of HIV, suggesting that induced CTLs could have biological significance. Besides, cells from at least some volunteers were able to kill cells infected with HIV from other clades, though the pattern of recognition was not uniform among volunteers. The canarypox vector is the first candidate HIV vaccine that has induced cross-clade functional CTL responses. The first phase I trial of the candidate vaccine in Africa was launched early in 1999 with Ugandan volunteers. The study determined the extent to which Ugandan volunteers have CTL that are active against the subtypes of HIV prevalent in Uganda, A and D. In 2015, a Phase I trial called HVTN 100 in South Africa tested the combination of a canarypox vector ALVAC and a gp120 protein adapted for the subtype C HIV common in sub-Saharan Africa, with the MF59 adjuvant. Those who received the vaccine regimen produced strong immune responses early on and the regimen was safe.<ref>{{cite journal | vauthors = Bekker LG, Moodie Z, Grunenberg N, Laher F, Tomaras GD, Cohen KW, Allen M, Malahleha M, Mngadi K, Daniels B, Innes C, Bentley C, Frahm N, Morris DE, Morris L, Mkhize NN, Montefiori DC, Sarzotti-Kelsoe M, Grant S, Yu C, Mehra VL, Pensiero MN, Phogat S, DiazGranados CA, Barnett SW, Kanesa-Thasan N, Koutsoukos M, Michael NL, Robb ML, Kublin JG, Gilbert PB, Corey L, Gray GE, McElrath MJ | display-authors = 6 | title = Subtype C ALVAC-HIV and bivalent subtype C gp120/MF59 HIV-1 vaccine in low-risk, HIV-uninfected, South African adults: a phase 1/2 trial | journal = The Lancet. HIV | volume = 5 | issue = 7 | pages = e366\u2013e378 | date = June 2018 | pmid = 29898870 | pmc = 6028742 | doi = 10.1016/S2352-3018(18)30071-7 }}</ref>\n\nOther strategies that have progressed to phase I trials in uninfected persons include peptides, [[lipopeptide]]s, [[DNA vaccination|DNA]], an [[attenuation (biology)|attenuated]] ''[[Salmonella]]'' vector, p24, etc. Specifically, candidate vaccines that induce one or more of the following are being sought:\n* [[neutralizing antibody|neutralizing antibodies]] active against a broad range of HIV primary isolates;\n* cytotoxic T cell responses in a vast majority of recipients;\n* strong mucosal [[immune response]]s.<ref>{{cite journal | vauthors = Pavot V, Rochereau N, Lawrence P, Girard MP, Genin C, Verrier B, Paul S | title = Recent progress in HIV vaccines inducing mucosal immune responses | journal = AIDS | volume = 28 | issue = 12 | pages = 1701\u201318 | date = July 2014 | pmid = 25009956 | doi = 10.1097/qad.0000000000000308 | s2cid = 28618851 }}</ref>\n\nIn 2011, researchers in National Biotech Centre in [[Madrid]] unveiled data from the Phase I clinical trial of their new vaccine, [[MVA-B]].  The vaccine induced an immunological response in 92% of the healthy subjects.<ref name="Fox News">{{cite news|url = http://www.foxnews.com/health/2011/09/29/new-vaccine-could-turn-hiv-into-minor-infection/|title = New Vaccine Could Turn HIV Into Minor Infection|access-date = 29 September 2011|work = Fox News|date = 2011-09-29|archive-date = 2011-09-29|archive-url = https://web.archive.org/web/20110929194708/http://www.foxnews.com/health/2011/09/29/new-vaccine-could-turn-hiv-into-minor-infection/|url-status = live}}</ref>\n\nIn 2016, results were published of the first Phase I human clinical trial of a killed whole-HIV-1 vaccine, [[SAV001]]. HIV used in the vaccine was chemically and physically deadened through radiation. The trial, conducted in Canada in 2012, demonstrated a good safety profile and elicited antibodies to HIV-1.<ref>{{cite journal | vauthors = Choi E, Michalski CJ, Choo SH, Kim GN, Banasikowska E, Lee S, Wu K, An HY, Mills A, Schneider S, Bredeek UF, Coulston DR, Ding S, Finzi A, Tian M, Klein K, Arts EJ, Mann JF, Gao Y, Kang CY | display-authors = 6 | title = First Phase I human clinical trial of a killed whole-HIV-1 vaccine: demonstration of its safety and enhancement of anti-HIV antibody responses | journal = Retrovirology | volume = 13 | issue = 1 | pages = 82 | date = November 2016 | pmid = 27894306 | pmc = 5126836 | doi = 10.1186/s12977-016-0317-2 }}</ref> According to Dr. Chil-Yong Kang of [[University of Western Ontario|Western University]]'s [[Schulich School of Medicine & Dentistry]] in Canada, the developer of this vaccine, antibodies against gp120 and p24 increased to 8-fold and 64-fold, respectively after vaccination.<ref name="urlHIV vaccine produces no adverse effects in trials">{{cite news|url=http://www.medicaldaily.com/new-hiv-vaccine-proves-successful-phase-1-human-trial-255439/|title=New HIV Vaccine Proves Successful In Phase 1 Human Trial|date=2013-09-04|work=Medical Daily|access-date=2013-09-04|location=New York|archive-date=2013-09-07|archive-url=https://web.archive.org/web/20130907013033/http://www.medicaldaily.com/new-hiv-vaccine-proves-successful-phase-1-human-trial-255439|url-status=live}}</ref>\n\n \n''Preventive HIV vaccines''\n* A recombinant Adenovirus-5 HIV vaccine (called V520) was tested in two Phase 2b studies, Phambili and STEP. On December 13, 2004, recruitment began for the [[STEP study]], a 3,000-participant [[Clinical trial#Phase II|phase II clinical trial]] of a novel HIV vaccine, at sites in North America, South America, the Caribbean and Australia.<ref>{{cite web |url=http://www.stepstudies.com/new/locations.shtml |title=STEP Study Locations |access-date=2008-11-04 |archive-url=https://web.archive.org/web/20080724081503/http://www.stepstudies.com/new/locations.shtml |archive-date=2008-07-24 |url-status=dead }}</ref>  The trial was co-funded by the [[National Institute of Allergy and Infectious Diseases]] (NIAID), which is a division of the [[National Institutes of Health]] (NIH), and the pharmaceutical company [[Merck & Co.]] Merck developed V520 to stimulate HIV-specific cellular immunity, which prompts the body to produce T cells that kill HIV-infected cells. In previous smaller trials, this vaccine was found to be safe, because of the lack of adverse effects on the participants. The vaccine showed induced cellular immune responses against HIV in more than half of volunteers.<ref name="AIDSepidemicupdate">{{cite web|author=Joint United Nations Programme on HIV/AIDS ([[UNAIDS]])|date=December 2005|title=AIDS epidemic update|url=https://www.who.int/hiv/epi-update2005_en.pdf|access-date=2014-04-22|publisher=[[World Health Organization]]|archive-date=2014-06-29|archive-url=https://web.archive.org/web/20140629031433/http://www.who.int/hiv/epi-update2005_en.pdf|url-status=live}}</ref> V520 contains a weakened [[adenovirus]] that serves as a carrier for three subtype B HIV genes (''gag,'' ''pol'' and ''nef''). Subtype B is the most prevalent HIV subtype in the regions of the study sites. Adenoviruses are among the main causes of upper respiratory tract ailments such as the [[common cold]]. Because the vaccine contains only three HIV genes housed in a weakened adenovirus, study participants cannot become infected with HIV or get a respiratory infection from the vaccine. It was announced in September 2007 that the trial for V520 would be stopped after it determined that vaccination with V520 appeared associated with an increased risk of HIV infection in some recipients.<ref>[http://www.hvtn.org/science/step_buch.html Efficacy Results from the STEP Study (Merck V520 Protocol 023/HVTN 502): A Phase II Test-of-Concept Trial of the MRKAd5 HIV-1 Gag/Pol/Nef Trivalent Vaccine] {{webarchive|url=https://web.archive.org/web/20110726164651/http://www.hvtn.org/science/step_buch.html |date=2011-07-26 }}</ref> The foremost issue facing the recombinant adenovirus that was used is the high prevalence of the adenovirus-specific antibodies as a result of prior exposure to adenovirus. Adenovirus vectors and many other [[viral vector vaccine|viral vectors]] currently used in HIV vaccines will induce a rapid memory immune response against the vector. This results in an impediment to the development of a T cell response against the inserted antigen (HIV antigens)<ref>{{cite journal | vauthors = Sekaly RP | title = The failed HIV Merck vaccine study: a step back or a launching point for future vaccine development? | journal = The Journal of Experimental Medicine | volume = 205 | issue = 1 | pages = 7\u201312 | date = January 2008 | pmid = 18195078 | pmc = 2234358 | doi = 10.1084/jem.20072681 }}</ref> The results of the trial prompted the reexamination of vaccine development strategies.<ref name="pmid18597681">{{cite journal | vauthors = Iaccino E, Schiavone M, Fiume G, Quinto I, Scala G | title = The aftermath of the Merck's HIV vaccine trial | journal = Retrovirology | volume = 5 | pages = 56 | date = July 2008 | pmid = 18597681 | pmc = 2483718 | doi = 10.1186/1742-4690-5-56 }}</ref>\n* [[HVTN 505]], a Phase IIb study, was launched in 2009 but halted in 2013 due to meeting requirements of futility.\n* It had been observed that a few, but not all, HIV-infected individuals naturally produce broadly neutralizing antibodies which keep the virus suppressed, and these people [[Long-term nonprogressor|remain asymptomatic for decades]]. Potential broadly neutralizing antibodies have been cloned in the laboratory (monoclonal antibodies) and are being tested in passive vaccination [[clinical trial]]s.<ref>{{Cite journal|last=International AIDS Vaccine Initiative|date=2021-09-29|others=ModernaTX, Inc., The University of Texas at San Antonio, George Washington University, Fred Hutchinson Cancer Research Center, Emory University|title=A Phase 1, Randomized, First-in-human, Open-label Study to Evaluate the Safety and Immunogenicity of eOD-GT8 60mer mRNA Vaccine (mRNA-1644) and Core-g28v2 60mer mRNA Vaccine (mRNA-1644v2-Core) in HIV-1 Uninfected Adults in Good General Health|url=https://clinicaltrials.gov/ct2/show/NCT05001373|journal=|access-date=2021-11-30|archive-date=2021-11-30|archive-url=https://web.archive.org/web/20211130203340/https://clinicaltrials.gov/ct2/show/NCT05001373|url-status=live}}</ref> In May 2016, there was the launch of the Antibody Mediated Prevention (AMP) trials (HVTN 703 and HVTN 704), the first phase IIb trials of a monoclonal antibody for HIV prevention. HVTN 703 and HVTN 704 found that the VRC01 monoclonal antibody, which targets the CD4 binding site, was not able to prevent HIV acquisition.<ref>{{Cite journal|last1=Corey|first1=Lawrence|last2=Gilbert|first2=Peter B.|last3=Juraska|first3=Michal|last4=Montefiori|first4=David C.|last5=Morris|first5=Lynn|last6=Karuna|first6=Shelly T.|last7=Edupuganti|first7=Srilatha|last8=Mgodi|first8=Nyaradzo M.|last9=deCamp|first9=Allan C.|last10=Rudnicki|first10=Erika|last11=Huang|first11=Yunda|date=2021-03-18|title=Two Randomized Trials of Neutralizing Antibodies to Prevent HIV-1 Acquisition|journal=The New England Journal of Medicine|volume=384|issue=11|pages=1003\u20131014|doi=10.1056/NEJMoa2031738|issn=1533-4406|pmc=8189692|pmid=33730454}}</ref>\n* In 2017, Janssen and the HVTN launched the phase IIb trial called HVTN 705/Imbokodo, testing the mosaic vector vaccine Ad26.Mos4.HIV and the aluminum phosphate-adjuvanted Clade C gp140 vaccines which are designed to prevent infection of all HIV subtypes around the world.<ref>{{Cite web|url=https://www.firstpost.com/tech/science/candidate-for-new-aids-vaccine-advances-to-next-phase-of-pre-approval-trials-4690471.html|title=Candidate for new AIDS vaccine advances to next phase of pre-approval trials- Technology News, Firstpost|website=Tech2|language=en-US|access-date=2018-07-11|date=2018-07-08|archive-date=2018-07-11|archive-url=https://web.archive.org/web/20180711225342/https://www.firstpost.com/tech/science/candidate-for-new-aids-vaccine-advances-to-next-phase-of-pre-approval-trials-4690471.html|url-status=live}}</ref> In 2021 the [[NIH]] announced that the Imbokodo Phase 2b study did not provide statistically significant reduction in HIV infection.<ref name=nih2021>{{cite web |title=HIV Vaccine Candidate Does Not Sufficiently Protect Women Against HIV Infection |url=https://www.nih.gov/news-events/news-releases/hiv-vaccine-candidate-does-not-sufficiently-protect-women-against-hiv-infection |website=National Institutes of Health (NIH) |access-date=1 September 2021 |language=EN |date=31 August 2021 |archive-date=31 August 2021 |archive-url=https://web.archive.org/web/20210831235052/https://www.nih.gov/news-events/news-releases/hiv-vaccine-candidate-does-not-sufficiently-protect-women-against-hiv-infection |url-status=live }}</ref>\n* In 2019, Terevac-VIH, a vaccine from Cuba, was determined to have passed the first stage of clinical trials after two years and move to the second stage of development.<ref>{{Cite web |url=https://thegeekherald.com/p/cure-for-hiv-aids-cuba-makes-a-breakthrough-nih-and-gate-foundation-will-donate-for-future-research/ |title=Archived copy |access-date=2021-12-11 |archive-date=2021-12-11 |archive-url=https://web.archive.org/web/20211211203908/https://thegeekherald.com/p/cure-for-hiv-aids-cuba-makes-a-breakthrough-nih-and-gate-foundation-will-donate-for-future-research/ |url-status=live }}</ref><ref>{{Cite web |url=https://www.cmhw.cu/en/science-and-health/5289-successful-clinical-trials-of-hiv-vaccine-in-cuba |title=Archived copy |access-date=2021-12-11 |archive-date=2021-12-11 |archive-url=https://web.archive.org/web/20211211203244/https://www.cmhw.cu/en/science-and-health/5289-successful-clinical-trials-of-hiv-vaccine-in-cuba |url-status=live }}</ref>\n\n''Therapeutic HIV vaccines''\n\nBiosantech developed a therapeutic vaccine called Tat Oyi, which targets the tat protein of HIV. It was tested in France in a double-blind Phase I/II trial with 48 HIV-positive patients who had reached viral suppression on [[Highly active antiretroviral therapy|Highly Active Antiretroviral Therapy]] and then stopped antiretrovirals after getting the intradermal Tat Oyi vaccine.<ref>{{cite journal | vauthors = Loret EP, Darque A, Jouve E, Loret EA, Nicolino-Brunet C, Morange S, Castanier E, Casanova J, Caloustian C, Bornet C, Coussirou J, Boussetta J, Couallier V, Blin O, Dussol B, Ravaux I | display-authors = 6 | title = Intradermal injection of a Tat Oyi-based therapeutic HIV vaccine reduces of 1.5 log copies/mL the HIV RNA rebound median and no HIV DNA rebound following cART interruption in a phase I/II randomized controlled clinical trial | journal = Retrovirology | volume = 13 | pages = 21 | date = April 2016 | pmid = 27036656 | pmc = 4818470 | doi = 10.1186/s12977-016-0251-3 }}</ref>\n\n ''Preventive HIV vaccines''\n\nThere have been no passive preventive HIV vaccines to reach Phase III yet, but some active preventive HIV vaccine candidates have entered Phase III.\n* In February 2003, [[VaxGen]] announced that their [[AIDSVAX|AIDSVAX B/E]] vaccine was a failure in [[North America]] as there was not a statistically significant reduction of HIV infection within the study population.\n* AIDSVAX B/E was a component, along with ALVAC, of the [[RV 144]] vaccine trial in Thailand that showed partial efficacy in preventing HIV. The AIDSVAX B/E and ALVAC vaccines targeted the [[gp120]] part of the HIV envelope. The study involved 16,395 participants who did not have HIV infection, 8197 of whom were given treatment consisting of two experimental vaccines targeting [[Subtypes of HIV|HIV types B and E]] that are prevalent in Thailand, while 8198 were given a placebo. The participants were tested for HIV every six months for three years. After three years, the vaccine group had HIV infection rates reduced by about 30% compared with those in the placebo group. However, after taking into account the seven people who already had HIV before getting vaccinated (two in the placebo group, five in the vaccine group) the difference was 26%.<ref name="Rerks-Ngarm2009">{{cite journal | vauthors = Rerks-Ngarm S, Pitisuttithum P, Nitayaphan S, Kaewkungwal J, Chiu J, Paris R, Premsri N, Namwat C, de Souza M, Adams E, Benenson M, Gurunathan S, Tartaglia J, McNeil JG, Francis DP, Stablein D, Birx DL, Chunsuttiwat S, Khamboonruang C, Thongcharoen P, Robb ML, Michael NL, Kunasol P, Kim JH | display-authors = 6 | title = Vaccination with ALVAC and AIDSVAX to prevent HIV-1 infection in Thailand | journal = The New England Journal of Medicine | volume = 361 | issue = 23 | pages = 2209\u201320 | date = December 2009 | pmid = 19843557 | doi = 10.1056/NEJMoa0908492 }}</ref> It was discovered that participants receiving vaccines in the RV 144 trial who produced [[Immunoglobulin G|IgG]] antibodies against the [[V2 loop]] of the [[Envelope glycoprotein GP120|HIV outer envelope]] were 43% less likely to become infected than those who did not, while [[IgA]] production was associated with a 54% greater risk of infection than those who did not produce the antibodies (but not worse than placebo). Viruses collected from vaccinated participants had mutations in the V2 region. Tests of a vaccine for [[Simian immunodeficiency virus|SIV]] in monkeys found greater resistance to SIV in animals producing antibodies against this region. Therefore, further research is expected to focus on creating vaccines designed to provoke an IgG reaction against the V2 loop.<ref>{{cite journal | title = Clues emerge to explain first successful HIV vaccine trial | journal = Nature | first = Ewen | last = Callaway | name-list-style = vanc | date=16 September 2011 | doi = 10.1038/news.2011.541 }}</ref>\n* In 2020, the phase IIb-III trial {{visible anchor|[[HVTN 702]]}}/"Uhambo" found that ALVAC/gp120/MF59 vaccinations were safe, and caused no harm, but had no efficacy in HIV prevention in [[South Africa]]. Vaccinations with the Uhambo vaccine regimen began late 2016 and stopped early 2020.<ref>{{cite web |url=https://www.nih.gov/news-events/news-releases/experimental-hiv-vaccine-regimen-ineffective-preventing-hiv |title=Experimental HIV vaccine regimen ineffective in preventing HIV |publisher=NIH |date=3 February 2020 |access-date=4 February 2020 |archive-date=4 February 2020 |archive-url=https://web.archive.org/web/20200204053128/https://www.nih.gov/news-events/news-releases/experimental-hiv-vaccine-regimen-ineffective-preventing-hiv |url-status=live }}</ref>\n* In 2020, the Ad26.Mos4.HIV plus adjuvanted clade C gp140 vaccine regimen entered a phase III trial called HVTN 706/"Mosaico". The regimen is a combination of an adenovirus vector vaccine engineered against multiple global strains of HIV, and a protein vaccine.<ref>{{cite web|url=https://www.nih.gov/news-events/news-releases/nih-partners-launch-hiv-vaccine-efficacy-trial-americas-europe|title=NIH and partners to launch HIV vaccine efficacy trial in the Americas and Europe|last=15 July 2019|date=2019-07-15|publisher=[[National Institutes of Health]]|access-date=23 July 2019|archive-date=23 July 2019|archive-url=https://web.archive.org/web/20190723131154/https://www.nih.gov/news-events/news-releases/nih-partners-launch-hiv-vaccine-efficacy-trial-americas-europe|url-status=live}}</ref>\n''Therapeutic HIV vaccines''\n\nNo therapeutic HIV vaccine candidates have reached phase 3 testing yet.\n\n A July 2012 report of the HIV Vaccines & Microbicides Resource Tracking Working Group estimates that $845 million was invested in HIV vaccine research in 2011.<ref name="url Investing to End the AIDS Epidemic: A new Era for HIV Prevention Research and Development">{{cite web | url = http://www.hivresourcetracking.org/sites/default/files/July%202012%20Investing%20to%20End%20the%20AIDS%20Epidemic-%20A%20New%20Era%20for%20HIV%20Prevention%20Research%20&%20Development.pdf | title = Investing to End the AIDS Epidemic: A new Era for HIV Prevention Research and Development|access-date=2010-12-13|url-status=dead | archive-url=https://web.archive.org/web/20121214073131/http://www.hivresourcetracking.org/sites/default/files/July%202012%20Investing%20to%20End%20the%20AIDS%20Epidemic-%20A%20New%20Era%20for%20HIV%20Prevention%20Research%20%26%20Development.pdf|archive-date=2012-12-14 }}</ref>\n\nEconomic issues with developing an AIDS vaccine include the need for advance purchase commitment (or [[advance market commitments]]) because after an AIDS vaccine has been developed, governments and NGOs may be able to bid the price down to [[marginal cost]].<ref name="url_SSRN">{{Cite journal | vauthors = Berndt ER, Glennerster R, Kremer M, Lee J, Levine R, Weizsacker G, Williams HL | display-authors = 6 | title = Advanced Purchase Commitments for a Malaria Vaccine: Estimating Costs and Effectiveness | date = April 2005 | ssrn = 696741 | doi = 10.2139/ssrn.696741 | periodical = NBER Working Paper | url = http://eprints.lse.ac.uk/19301/1/Advanced_Purchase_Commitments_for_a_Malaria_Vaccine_Estimating_Costs_and_Effectiveness.pdf | journal =  | access-date = 2021-12-11 | archive-date = 2013-07-21 | archive-url = https://web.archive.org/web/20130721081149/http://eprints.lse.ac.uk/19301/1/Advanced_Purchase_Commitments_for_a_Malaria_Vaccine_Estimating_Costs_and_Effectiveness.pdf | url-status = live }}</ref>\n\n Theoretically, any possible HIV vaccine must inhibit or stop the HIV virion replication cycle.<ref>{{cite book | last1 = Collier | first1 = Leslie | last2 = Balows | first2 = Albert | last3 = Sussman | first3 = Max | date = 1998 | series = Topley and Wilson's Microbiology and Microbial Infections | edition = ninth | volume = 1 | title = Virology | editor1-last = Mahy | editor1-first = Brian | editor2-last = Collier | editor2-first =  Leslie | name-list-style = vanc | publisher = Hodder Education Publishers | isbn = 978-0-340-66316-5 | pages = 75\u201391 }}</ref> The targets of a vaccine could be the following stages of the HIV virion cycle:\n* Stage I. Free state\n* Stage II. Attachment\n* Stage III. Penetration\n* Stage IV. Uncoating\n* Stage V. Replication\n* Stage VI. Assembling\n* Stage VII. Releasing\n\nTherefore, the following list comprises the current possible approaches for an HIV vaccine:\n\n * Biological, chemical and/or physical approaches for removing the HIV virions from the blood.\n\n * [[Phagocytosis]] of the HIV virions.\n* Chemical or organically based capture (creation of any skin or additional membrane around the virion) of HIV virions\n* Chemical or organic attachments to the virion\n\n Here, "damage" means inhibiting or stopping the ability of virion to process any of the ''Phase II-VII''. Here are the different classification of methods:\n* By nature of method:\n** Physical methods (''Stage I-VII'')\n** Chemical and biological methods (''Stage I-VII'')\n* By damaging target of the [[HIV#Structure and genome|HIV virion structure]]:<ref>{{cite journal | vauthors = McGovern SL, Caselli E, Grigorieff N, Shoichet BK | title = A common mechanism underlying promiscuous inhibitors from virtual and high-throughput screening | journal = Journal of Medicinal Chemistry | volume = 45 | issue = 8 | pages = 1712\u201322 | date = April 2002 | pmid = 11931626 | doi = 10.1021/jm010533y }}</ref><ref>Compared with overview in: Fisher, Bruce; Harvey, Richard P.; Champe, Pamela C. (2007). Lippincott's Illustrated Reviews: Microbiology (Lippincott's Illustrated Reviews Series). Hagerstown, MD: Lippincott Williams & Wilkins. {{ISBN|0-7817-8215-5}}. Page 3</ref>\n** Damaging the [[Envelope glycoprotein GP120|Docking Glycoprotein gp120]]<ref>{{cite report | title = HIV Sequence Compendium | year = 2017 | vauthors = Foley B, Leitner T, Apetrei C, Hahn B, Mizrachi I, Mullins J, Rambaut A, Wolinsky S, Korber B | publisher = Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, NM, LA-UR 17-25240 }}</ref> (''Stage I-III, VI, VII'')\n** Damaging the [[Gp41|Transmembrane Glycoprotein gp41]]<ref>{{cite journal | vauthors = Malashkevich VN, Chan DC, Chutkowski CT, Kim PS | title = Crystal structure of the simian immunodeficiency virus (SIV) gp41 core: conserved helical interactions underlie the broad inhibitory activity of gp41 peptides | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 95 | issue = 16 | pages = 9134\u20139 | date = August 1998 | pmid = 9689046 | pmc = 21304 | doi = 10.1073/pnas.95.16.9134 | bibcode = 1998PNAS...95.9134M | doi-access = free }}</ref> (''Stage I-III, VI, VII'')\n** Damaging the virion matrix (''Stage I-III, VI, VII'')\n** Damaging the virion Capsid (''Stage I-III, VI, VII'')\n** Damaging the Reverse Transcriptase (''Stage I-VII'')\n** Damaging the RNA (''Stage I-VII'')\n\n * Insertion into blood chemical or organic compounds which binds to the [[gp120]]. Hypothetically, it can be pieces of the [[CD4]] cell membranes with receptors. Any chemical and organic alternative (with the ability to bind the gp120) of these receptors also can be used.\n* Insertion into blood chemical or organic compounds which binds to the receptors of the CD4 cells.\n\n * Biological, chemical or physical approach to inhibit the ''Attachment, Penetration, Uncoating, Integration, Replication, Assembling and/or Releasing.''\n\n Inhibiting the life functions of infected cells:\n* Inhibiting the metabolism of infected cells\n* Inhibiting the energy exchange of infected cells\n\n \nThere have been reports that HIV patients coinfected with ''[[GB virus C]]'' (GBV-C), also called hepatitis G virus, can survive longer than those without GBV-C, but the patients may be different in other ways. GBV-C is potentially useful in the future development of an HIV vaccine.<ref>{{cite journal | vauthors = Bagasra O, Bagasra AU, Sheraz M, Pace DG | title = Potential utility of GB virus type C as a preventive vaccine for HIV-1 | journal = Expert Review of Vaccines | volume = 11 | issue = 3 | pages = 335\u201347 | date = March 2012 | pmid = 22380825 | doi = 10.1586/erv.11.191 | s2cid = 26476119 }}</ref>\n\nLive attenuated vaccines are highly successful against polio, rotavirus and measles, but have not been tested against HIV in humans. Reversion to live virus has been a theoretical safety concern that has to date prevented clinical development of a live attenuated HIV-1 vaccine. Scientists are researching novel strategies to develop a non-virulent live attenuated HIV-1 vaccine. For example, a genetically modified form of HIV has been created in which the virus's [[codons]] (a sequence of three [[nucleotides]] that form genetic code) are manipulated to rely on an [[Non-proteinogenic amino acids|unnatural amino acid]] for proper protein translation, which allows it to replicate. Because this amino acid is foreign to the human body, the virus cannot reproduce.<ref>{{cite journal | vauthors = Wang N, Li Y, Niu W, Sun M, Cerny R, Li Q, Guo J | title = Construction of a live-attenuated HIV-1 vaccine through genetic code expansion | journal = Angewandte Chemie | volume = 53 | issue = 19 | pages = 4867\u201371 | date = May 2014 | pmid = 24715496 | pmc = 4984542 | doi = 10.1002/anie.201402092 }}</ref>\n\n {{Portal|Viruses}}\n* [[Cabotegravir]]\n* [[COVID-19 vaccine]]\n* [[HIV Vaccine Trials Network]]\n* [[World AIDS Vaccine Day]]\n*[[Broadly neutralizing HIV-1 antibodies]]\n\n {{Reflist|colwidth=30em}}\n\n * [https://web.archive.org/web/20070817112159/http://www.vrc.nih.gov/ Vaccine Research Center (VRC)]- Information concerning Preventive HIV vaccine research studies\n* [https://www.niaid.nih.gov/diseases-conditions/hiv-vaccine-development NIAID HIV vaccine site] ([[Division of Acquired Immunodeficiency Syndrome|DAIDS]])\n* [http://www.vaccinealliance.org Global Alliance for Vaccines and Immunization (GAVI)]\n* [http://www.iavi.org International AIDS Vaccine Initiative (IAVI)]\n* [http://www.avac.org AIDS Vaccine Advocacy Coalition (AVAC)]\n* [http://www.hivresearch.org U.S. Military HIV Research Program (MHRP)]\n* [http://briandeer.com/vaxgen-aidsvax.htm Investigation of first candidate vaccine]\n* [https://www.hiv.gov/ HIV.gov - The U.S. Federal Domestic HIV/AIDS Resource]\n* [https://web.archive.org/web/19991123222842/http://hivtest.org/ HIVtest.org - Find an HIV testing site near you]\n* [https://www.nytimes.com/2019/03/08/health/hiv-aids-research.html Bit by Bit, Scientists Gain Ground on AIDS] - The New York Times, March 8, 2019\n* [http://www.treatmentactiongroup.org/cure/trials Treatment Action Group]\n\n{{AIDS}}\n{{Vaccines}}\n{{Authority control}}", "HIV vaccine development --- Introduction ---|Difficulties in development": "In 1984, after it was confirmed that HIV caused AIDS, the United States [[Health and Human Services Secretary]] [[Margaret Heckler]] declared that a [[vaccine]] would be available within two years.<ref>{{cite book | last = Shilts | first = Randy | year = 1987 | title = And the Band Played On: Politics, People, and the AIDS Epidemic | edition = 2007 | publisher = St. Martin's Press | isbn = 978-0-312-24135-3 | page = [https://archive.org/details/andbandplayedonp00shil_0/page/451 451] | url-access = registration | url = https://archive.org/details/andbandplayedonp00shil_0/page/451 }}</ref> However, priming the [[adaptive immunity|adaptive immune]] system to recognize the [[viral envelope]] proteins did not prevent HIV acquisition. \n\nMany factors make the development of an HIV vaccine different from other classic vaccines:<ref>{{cite journal | vauthors = Fauci AS | year = 1996 | title = An HIV vaccine: breaking the paradigms | journal = Proc. Am. Assoc. Phys. | volume = 108 | issue = 1| pages = 6\u201313 | pmid = 8834058 }}</ref>\n* Classic vaccines mimic natural immunity against reinfection as seen in individuals recovered from infection; there are almost no recovered AIDS patients.{{Citation needed|date=January 2019}}\n* Most vaccines protect against disease, not against infection; HIV infection may remain latent for long periods before causing AIDS.\n* Most effective vaccines are whole-killed or live-attenuated organisms; killed HIV-1 does not retain antigenicity and the use of a live retrovirus vaccine raises safety issues.\n\n [[File:HIV structure cycle zh.png|thumb|HIV structure cycle]]\nThe [[epitope]]s of the viral envelope are more variable than those of many other viruses. Furthermore, the functionally important epitopes of the [[gp120]] protein are masked by [[glycosylation]], [[trimerisation]] and receptor-induced conformational changes making it difficult to block with neutralizing antibodies.\n\nThe ineffectiveness of previously developed vaccines primarily stems from two related factors:\n* First, HIV is highly mutable. Because of the virus's ability to rapidly respond to selective pressures imposed by the immune system, the population of virus in an infected individual typically evolves so that it can evade the two major arms of the adaptive immune system; humoral ([[antibody]]-mediated) and cellular (mediated by [[T cells]]) immunity.\n* Second, HIV isolates are themselves highly variable. HIV can be categorized into multiple subtypes with a high degree of genetic divergence. Therefore, the immune responses raised by any vaccine need to be broad enough to account for this variability. Any vaccine that lacks this breadth is unlikely to be effective.\n\nThe difficulties in stimulating a reliable [[antibody]] response has led to the attempts to develop a vaccine that stimulates a response by [[cytotoxic T-lymphocyte]]s.<ref name="pmid17502236">{{cite journal | vauthors = Kim D, Elizaga M, Duerr A | title = HIV vaccine efficacy trials: towards the future of HIV prevention | journal = Infectious Disease Clinics of North America | volume = 21 | issue = 1 | pages = 201\u201317, x | date = March 2007 | pmid = 17502236 | doi = 10.1016/j.idc.2007.01.006 }}</ref><ref name="pmid18425263">{{cite journal | vauthors = Watkins DI | title = The hope for an HIV vaccine based on induction of CD8+ T lymphocytes--a review | journal = Mem\u00f3rias do Instituto Oswaldo Cruz | volume = 103 | issue = 2 | pages = 119\u201329 | date = March 2008 | pmid = 18425263 | pmc = 2997999 | doi = 10.1590/S0074-02762008000200001 }}</ref>\n\nAnother response to the challenge has been to create a single peptide that contains the least variable components of all the known HIV strains.<ref name="pmid17912361">{{cite journal | vauthors = L\u00e9tourneau S, Im EJ, Mashishi T, Brereton C, Bridgeman A, Yang H, Dorrell L, Dong T, Korber B, McMichael AJ, Hanke T | title = Design and pre-clinical evaluation of a universal HIV-1 vaccine | journal = PLOS ONE | volume = 2 | issue = 10 | pages = e984 | date = October 2007 | pmid = 17912361 | pmc = 1991584 | doi = 10.1371/journal.pone.0000984 | editor1-last = Nixon | editor1-first = Douglas | bibcode = 2007PLoSO...2..984L | doi-access = free }}</ref>\n\n [[File:2006-12-09 Chipanzees D Bruyere.JPG|thumb| Young chimpanzees from [[Tchimpounga Sanctuary]] ([[Republic of the Congo]])]]\nThe typical [[animal model]] for vaccine research is the monkey, often the [[macaque]]. Monkeys can be infected with [[Simian immunodeficiency virus|SIV]] or the chimeric SHIV for research purposes. However, the well-proven route of trying to induce neutralizing antibodies by vaccination has stalled because of the great difficulty in stimulating antibodies that neutralise heterologous primary HIV isolates.<ref>{{cite journal | vauthors = Poignard P, Sabbe R, Picchio GR, Wang M, Gulizia RJ, Katinger H, Parren PW, Mosier DE, Burton DR | display-authors = 6 | title = Neutralizing antibodies have limited effects on the control of established HIV-1 infection in vivo | journal = Immunity | volume = 10 | issue = 4 | pages = 431\u20138 | date = April 1999 | pmid = 10229186 | doi = 10.1016/S1074-7613(00)80043-6 | doi-access = free }}</ref> Some vaccines based on the virus envelope have protected chimpanzees or macaques from homologous virus challenge,<ref>{{cite journal | vauthors = Berman PW, Gregory TJ, Riddle L, Nakamura GR, Champe MA, Porter JP, Wurm FM, Hershberg RD, Cobb EK, Eichberg JW | display-authors = 6 | title = Protection of chimpanzees from infection by HIV-1 after vaccination with recombinant glycoprotein gp120 but not gp160 | journal = Nature | volume = 345 | issue = 6276 | pages = 622\u20135 | date = June 1990 | pmid = 2190095 | doi = 10.1038/345622a0 | bibcode = 1990Natur.345..622B | s2cid = 4258128 }}</ref> but in clinical trials, humans who were immunised with similar constructs became infected after later exposure to HIV-1.<ref>{{cite journal | vauthors = Connor RI, Korber BT, Graham BS, Hahn BH, Ho DD, Walker BD, Neumann AU, Vermund SH, Mestecky J, Jackson S, Fenamore E, Cao Y, Gao F, Kalams S, Kunstman KJ, McDonald D, McWilliams N, Trkola A, Moore JP, Wolinsky SM | display-authors = 6 | title = Immunological and virological analyses of persons infected by human immunodeficiency virus type 1 while participating in trials of recombinant gp120 subunit vaccines | journal = Journal of Virology | volume = 72 | issue = 2 | pages = 1552\u201376 | date = February 1998 | pmid = 9445059 | pmc = 124637 | doi =  10.1128/JVI.72.2.1552-1576.1998}}</ref>\n\nThere are some differences between SIV and HIV that may introduce challenges in the use of an animal model. The animal model can be extremely useful but at times controversial.<ref>{{cite journal | vauthors = Morgan C, Marthas M, Miller C, Duerr A, Cheng-Mayer C, Desrosiers R, Flores J, Haigwood N, Hu SL, Johnson RP, Lifson J, Montefiori D, Moore J, Robert-Guroff M, Robinson H, Self S, Corey L | display-authors = 6 | title = The use of nonhuman primate models in HIV vaccine development | journal = PLOS Medicine | volume = 5 | issue = 8 | pages = e173 | date = August 2008 | pmid = 18700814 | pmc = 2504486 | doi = 10.1371/journal.pmed.0050173 | author-link8 = Nancy Haigwood }}</ref>\n\nThere is a new animal model strongly resembling that of HIV in humans. Generalized immune activation as a direct result of activated CD4+ T cell killing - performed in mice allows new ways of testing HIV behaviour.<ref>{{cite journal | vauthors = Marques R, Williams A, Eksmond U, Wullaert A, Killeen N, Pasparakis M, Kioussis D, Kassiotis G | display-authors = 6 | title = Generalized immune activation as a direct result of activated CD4+ T cell killing | journal = Journal of Biology | volume = 8 | issue = 10 | pages = 93 | year = 2009 | pmid = 19943952 | pmc = 2790834 | doi = 10.1186/jbiol194 }}</ref><ref>{{cite journal | vauthors = Vrisekoop N, Mandl JN, Germain RN | title = Life and death as a T lymphocyte: from immune protection to HIV pathogenesis | journal = Journal of Biology | volume = 8 | issue = 10 | pages = 91 | year = 2009 | pmid = 19951397 | pmc = 2790836 | doi = 10.1186/jbiol198 }}</ref>\n\n[[National Institute of Allergy and Infectious Diseases|NIAID]]-funded SIV research has shown that challenging monkeys with a [[cytomegalovirus]] (CMV)-based SIV vaccine results in containment of virus. Typically, virus replication and dissemination occurs within days after infection, whereas vaccine-induced T cell activation and recruitment to sites of viral replication take weeks. Researchers hypothesized that vaccines designed to maintain activated effector memory T cells might impair viral replication at its earliest stage.{{Citation needed|date=October 2012}}", "HIV vaccine development --- Introduction ---|Clinical trials": "Several vaccine candidates are in varying phases of [[clinical trial]]s.\n\n Most initial approaches have focused on the [[HIV envelope]] protein. At least thirteen different [[gp120]] and [[gp160]] envelope candidates have been evaluated, in the US predominantly through the AIDS Vaccine Evaluation Group. Most research focused on gp120 rather than gp41/gp160, as the latter is generally more difficult to produce and did not initially offer any clear advantage over gp120 forms. Overall, they have been safe and immunogenic in diverse populations, have induced neutralizing antibody in nearly 100% recipients, but rarely induced [[Cytotoxic T cell|CD8+ cytotoxic T lymphocytes]] (CTL). Mammalian derived envelope preparations have been better inducers of neutralizing antibody than candidates produced in yeast and bacteria. Although the vaccination process involved many repeated "[[booster dose|booster]]" injections, it was challenging to induce and maintain the high anti-gp120 antibody [[titer]]s necessary to have any hope of neutralizing an HIV exposure.{{citation needed|date=January 2021}}\n\nThe availability of several recombinant [[canarypox]] [[Viral vector vaccine|vectors]] has provided interesting results that may prove to be generalizable to other [[viral vector]]s. Increasing the complexity of the canarypox vectors by including more genes/epitopes has increased the percent of volunteers that have detectable CTL to a greater extent than did increase the dose of the viral vector. CTLs from volunteers were able to kill [[PBMC|peripheral blood mononuclear cells]] infected with primary isolates of HIV, suggesting that induced CTLs could have biological significance. Besides, cells from at least some volunteers were able to kill cells infected with HIV from other clades, though the pattern of recognition was not uniform among volunteers. The canarypox vector is the first candidate HIV vaccine that has induced cross-clade functional CTL responses. The first phase I trial of the candidate vaccine in Africa was launched early in 1999 with Ugandan volunteers. The study determined the extent to which Ugandan volunteers have CTL that are active against the subtypes of HIV prevalent in Uganda, A and D. In 2015, a Phase I trial called HVTN 100 in South Africa tested the combination of a canarypox vector ALVAC and a gp120 protein adapted for the subtype C HIV common in sub-Saharan Africa, with the MF59 adjuvant. Those who received the vaccine regimen produced strong immune responses early on and the regimen was safe.<ref>{{cite journal | vauthors = Bekker LG, Moodie Z, Grunenberg N, Laher F, Tomaras GD, Cohen KW, Allen M, Malahleha M, Mngadi K, Daniels B, Innes C, Bentley C, Frahm N, Morris DE, Morris L, Mkhize NN, Montefiori DC, Sarzotti-Kelsoe M, Grant S, Yu C, Mehra VL, Pensiero MN, Phogat S, DiazGranados CA, Barnett SW, Kanesa-Thasan N, Koutsoukos M, Michael NL, Robb ML, Kublin JG, Gilbert PB, Corey L, Gray GE, McElrath MJ | display-authors = 6 | title = Subtype C ALVAC-HIV and bivalent subtype C gp120/MF59 HIV-1 vaccine in low-risk, HIV-uninfected, South African adults: a phase 1/2 trial | journal = The Lancet. HIV | volume = 5 | issue = 7 | pages = e366\u2013e378 | date = June 2018 | pmid = 29898870 | pmc = 6028742 | doi = 10.1016/S2352-3018(18)30071-7 }}</ref>\n\nOther strategies that have progressed to phase I trials in uninfected persons include peptides, [[lipopeptide]]s, [[DNA vaccination|DNA]], an [[attenuation (biology)|attenuated]] ''[[Salmonella]]'' vector, p24, etc. Specifically, candidate vaccines that induce one or more of the following are being sought:\n* [[neutralizing antibody|neutralizing antibodies]] active against a broad range of HIV primary isolates;\n* cytotoxic T cell responses in a vast majority of recipients;\n* strong mucosal [[immune response]]s.<ref>{{cite journal | vauthors = Pavot V, Rochereau N, Lawrence P, Girard MP, Genin C, Verrier B, Paul S | title = Recent progress in HIV vaccines inducing mucosal immune responses | journal = AIDS | volume = 28 | issue = 12 | pages = 1701\u201318 | date = July 2014 | pmid = 25009956 | doi = 10.1097/qad.0000000000000308 | s2cid = 28618851 }}</ref>\n\nIn 2011, researchers in National Biotech Centre in [[Madrid]] unveiled data from the Phase I clinical trial of their new vaccine, [[MVA-B]].  The vaccine induced an immunological response in 92% of the healthy subjects.<ref name="Fox News">{{cite news|url = http://www.foxnews.com/health/2011/09/29/new-vaccine-could-turn-hiv-into-minor-infection/|title = New Vaccine Could Turn HIV Into Minor Infection|access-date = 29 September 2011|work = Fox News|date = 2011-09-29|archive-date = 2011-09-29|archive-url = https://web.archive.org/web/20110929194708/http://www.foxnews.com/health/2011/09/29/new-vaccine-could-turn-hiv-into-minor-infection/|url-status = live}}</ref>\n\nIn 2016, results were published of the first Phase I human clinical trial of a killed whole-HIV-1 vaccine, [[SAV001]]. HIV used in the vaccine was chemically and physically deadened through radiation. The trial, conducted in Canada in 2012, demonstrated a good safety profile and elicited antibodies to HIV-1.<ref>{{cite journal | vauthors = Choi E, Michalski CJ, Choo SH, Kim GN, Banasikowska E, Lee S, Wu K, An HY, Mills A, Schneider S, Bredeek UF, Coulston DR, Ding S, Finzi A, Tian M, Klein K, Arts EJ, Mann JF, Gao Y, Kang CY | display-authors = 6 | title = First Phase I human clinical trial of a killed whole-HIV-1 vaccine: demonstration of its safety and enhancement of anti-HIV antibody responses | journal = Retrovirology | volume = 13 | issue = 1 | pages = 82 | date = November 2016 | pmid = 27894306 | pmc = 5126836 | doi = 10.1186/s12977-016-0317-2 }}</ref> According to Dr. Chil-Yong Kang of [[University of Western Ontario|Western University]]'s [[Schulich School of Medicine & Dentistry]] in Canada, the developer of this vaccine, antibodies against gp120 and p24 increased to 8-fold and 64-fold, respectively after vaccination.<ref name="urlHIV vaccine produces no adverse effects in trials">{{cite news|url=http://www.medicaldaily.com/new-hiv-vaccine-proves-successful-phase-1-human-trial-255439/|title=New HIV Vaccine Proves Successful In Phase 1 Human Trial|date=2013-09-04|work=Medical Daily|access-date=2013-09-04|location=New York|archive-date=2013-09-07|archive-url=https://web.archive.org/web/20130907013033/http://www.medicaldaily.com/new-hiv-vaccine-proves-successful-phase-1-human-trial-255439|url-status=live}}</ref>\n\n \n''Preventive HIV vaccines''\n* A recombinant Adenovirus-5 HIV vaccine (called V520) was tested in two Phase 2b studies, Phambili and STEP. On December 13, 2004, recruitment began for the [[STEP study]], a 3,000-participant [[Clinical trial#Phase II|phase II clinical trial]] of a novel HIV vaccine, at sites in North America, South America, the Caribbean and Australia.<ref>{{cite web |url=http://www.stepstudies.com/new/locations.shtml |title=STEP Study Locations |access-date=2008-11-04 |archive-url=https://web.archive.org/web/20080724081503/http://www.stepstudies.com/new/locations.shtml |archive-date=2008-07-24 |url-status=dead }}</ref>  The trial was co-funded by the [[National Institute of Allergy and Infectious Diseases]] (NIAID), which is a division of the [[National Institutes of Health]] (NIH), and the pharmaceutical company [[Merck & Co.]] Merck developed V520 to stimulate HIV-specific cellular immunity, which prompts the body to produce T cells that kill HIV-infected cells. In previous smaller trials, this vaccine was found to be safe, because of the lack of adverse effects on the participants. The vaccine showed induced cellular immune responses against HIV in more than half of volunteers.<ref name="AIDSepidemicupdate">{{cite web|author=Joint United Nations Programme on HIV/AIDS ([[UNAIDS]])|date=December 2005|title=AIDS epidemic update|url=https://www.who.int/hiv/epi-update2005_en.pdf|access-date=2014-04-22|publisher=[[World Health Organization]]|archive-date=2014-06-29|archive-url=https://web.archive.org/web/20140629031433/http://www.who.int/hiv/epi-update2005_en.pdf|url-status=live}}</ref> V520 contains a weakened [[adenovirus]] that serves as a carrier for three subtype B HIV genes (''gag,'' ''pol'' and ''nef''). Subtype B is the most prevalent HIV subtype in the regions of the study sites. Adenoviruses are among the main causes of upper respiratory tract ailments such as the [[common cold]]. Because the vaccine contains only three HIV genes housed in a weakened adenovirus, study participants cannot become infected with HIV or get a respiratory infection from the vaccine. It was announced in September 2007 that the trial for V520 would be stopped after it determined that vaccination with V520 appeared associated with an increased risk of HIV infection in some recipients.<ref>[http://www.hvtn.org/science/step_buch.html Efficacy Results from the STEP Study (Merck V520 Protocol 023/HVTN 502): A Phase II Test-of-Concept Trial of the MRKAd5 HIV-1 Gag/Pol/Nef Trivalent Vaccine] {{webarchive|url=https://web.archive.org/web/20110726164651/http://www.hvtn.org/science/step_buch.html |date=2011-07-26 }}</ref> The foremost issue facing the recombinant adenovirus that was used is the high prevalence of the adenovirus-specific antibodies as a result of prior exposure to adenovirus. Adenovirus vectors and many other [[viral vector vaccine|viral vectors]] currently used in HIV vaccines will induce a rapid memory immune response against the vector. This results in an impediment to the development of a T cell response against the inserted antigen (HIV antigens)<ref>{{cite journal | vauthors = Sekaly RP | title = The failed HIV Merck vaccine study: a step back or a launching point for future vaccine development? | journal = The Journal of Experimental Medicine | volume = 205 | issue = 1 | pages = 7\u201312 | date = January 2008 | pmid = 18195078 | pmc = 2234358 | doi = 10.1084/jem.20072681 }}</ref> The results of the trial prompted the reexamination of vaccine development strategies.<ref name="pmid18597681">{{cite journal | vauthors = Iaccino E, Schiavone M, Fiume G, Quinto I, Scala G | title = The aftermath of the Merck's HIV vaccine trial | journal = Retrovirology | volume = 5 | pages = 56 | date = July 2008 | pmid = 18597681 | pmc = 2483718 | doi = 10.1186/1742-4690-5-56 }}</ref>\n* [[HVTN 505]], a Phase IIb study, was launched in 2009 but halted in 2013 due to meeting requirements of futility.\n* It had been observed that a few, but not all, HIV-infected individuals naturally produce broadly neutralizing antibodies which keep the virus suppressed, and these people [[Long-term nonprogressor|remain asymptomatic for decades]]. Potential broadly neutralizing antibodies have been cloned in the laboratory (monoclonal antibodies) and are being tested in passive vaccination [[clinical trial]]s.<ref>{{Cite journal|last=International AIDS Vaccine Initiative|date=2021-09-29|others=ModernaTX, Inc., The University of Texas at San Antonio, George Washington University, Fred Hutchinson Cancer Research Center, Emory University|title=A Phase 1, Randomized, First-in-human, Open-label Study to Evaluate the Safety and Immunogenicity of eOD-GT8 60mer mRNA Vaccine (mRNA-1644) and Core-g28v2 60mer mRNA Vaccine (mRNA-1644v2-Core) in HIV-1 Uninfected Adults in Good General Health|url=https://clinicaltrials.gov/ct2/show/NCT05001373|journal=|access-date=2021-11-30|archive-date=2021-11-30|archive-url=https://web.archive.org/web/20211130203340/https://clinicaltrials.gov/ct2/show/NCT05001373|url-status=live}}</ref> In May 2016, there was the launch of the Antibody Mediated Prevention (AMP) trials (HVTN 703 and HVTN 704), the first phase IIb trials of a monoclonal antibody for HIV prevention. HVTN 703 and HVTN 704 found that the VRC01 monoclonal antibody, which targets the CD4 binding site, was not able to prevent HIV acquisition.<ref>{{Cite journal|last1=Corey|first1=Lawrence|last2=Gilbert|first2=Peter B.|last3=Juraska|first3=Michal|last4=Montefiori|first4=David C.|last5=Morris|first5=Lynn|last6=Karuna|first6=Shelly T.|last7=Edupuganti|first7=Srilatha|last8=Mgodi|first8=Nyaradzo M.|last9=deCamp|first9=Allan C.|last10=Rudnicki|first10=Erika|last11=Huang|first11=Yunda|date=2021-03-18|title=Two Randomized Trials of Neutralizing Antibodies to Prevent HIV-1 Acquisition|journal=The New England Journal of Medicine|volume=384|issue=11|pages=1003\u20131014|doi=10.1056/NEJMoa2031738|issn=1533-4406|pmc=8189692|pmid=33730454}}</ref>\n* In 2017, Janssen and the HVTN launched the phase IIb trial called HVTN 705/Imbokodo, testing the mosaic vector vaccine Ad26.Mos4.HIV and the aluminum phosphate-adjuvanted Clade C gp140 vaccines which are designed to prevent infection of all HIV subtypes around the world.<ref>{{Cite web|url=https://www.firstpost.com/tech/science/candidate-for-new-aids-vaccine-advances-to-next-phase-of-pre-approval-trials-4690471.html|title=Candidate for new AIDS vaccine advances to next phase of pre-approval trials- Technology News, Firstpost|website=Tech2|language=en-US|access-date=2018-07-11|date=2018-07-08|archive-date=2018-07-11|archive-url=https://web.archive.org/web/20180711225342/https://www.firstpost.com/tech/science/candidate-for-new-aids-vaccine-advances-to-next-phase-of-pre-approval-trials-4690471.html|url-status=live}}</ref> In 2021 the [[NIH]] announced that the Imbokodo Phase 2b study did not provide statistically significant reduction in HIV infection.<ref name=nih2021>{{cite web |title=HIV Vaccine Candidate Does Not Sufficiently Protect Women Against HIV Infection |url=https://www.nih.gov/news-events/news-releases/hiv-vaccine-candidate-does-not-sufficiently-protect-women-against-hiv-infection |website=National Institutes of Health (NIH) |access-date=1 September 2021 |language=EN |date=31 August 2021 |archive-date=31 August 2021 |archive-url=https://web.archive.org/web/20210831235052/https://www.nih.gov/news-events/news-releases/hiv-vaccine-candidate-does-not-sufficiently-protect-women-against-hiv-infection |url-status=live }}</ref>\n* In 2019, Terevac-VIH, a vaccine from Cuba, was determined to have passed the first stage of clinical trials after two years and move to the second stage of development.<ref>{{Cite web |url=https://thegeekherald.com/p/cure-for-hiv-aids-cuba-makes-a-breakthrough-nih-and-gate-foundation-will-donate-for-future-research/ |title=Archived copy |access-date=2021-12-11 |archive-date=2021-12-11 |archive-url=https://web.archive.org/web/20211211203908/https://thegeekherald.com/p/cure-for-hiv-aids-cuba-makes-a-breakthrough-nih-and-gate-foundation-will-donate-for-future-research/ |url-status=live }}</ref><ref>{{Cite web |url=https://www.cmhw.cu/en/science-and-health/5289-successful-clinical-trials-of-hiv-vaccine-in-cuba |title=Archived copy |access-date=2021-12-11 |archive-date=2021-12-11 |archive-url=https://web.archive.org/web/20211211203244/https://www.cmhw.cu/en/science-and-health/5289-successful-clinical-trials-of-hiv-vaccine-in-cuba |url-status=live }}</ref>\n\n''Therapeutic HIV vaccines''\n\nBiosantech developed a therapeutic vaccine called Tat Oyi, which targets the tat protein of HIV. It was tested in France in a double-blind Phase I/II trial with 48 HIV-positive patients who had reached viral suppression on [[Highly active antiretroviral therapy|Highly Active Antiretroviral Therapy]] and then stopped antiretrovirals after getting the intradermal Tat Oyi vaccine.<ref>{{cite journal | vauthors = Loret EP, Darque A, Jouve E, Loret EA, Nicolino-Brunet C, Morange S, Castanier E, Casanova J, Caloustian C, Bornet C, Coussirou J, Boussetta J, Couallier V, Blin O, Dussol B, Ravaux I | display-authors = 6 | title = Intradermal injection of a Tat Oyi-based therapeutic HIV vaccine reduces of 1.5 log copies/mL the HIV RNA rebound median and no HIV DNA rebound following cART interruption in a phase I/II randomized controlled clinical trial | journal = Retrovirology | volume = 13 | pages = 21 | date = April 2016 | pmid = 27036656 | pmc = 4818470 | doi = 10.1186/s12977-016-0251-3 }}</ref>\n\n ''Preventive HIV vaccines''\n\nThere have been no passive preventive HIV vaccines to reach Phase III yet, but some active preventive HIV vaccine candidates have entered Phase III.\n* In February 2003, [[VaxGen]] announced that their [[AIDSVAX|AIDSVAX B/E]] vaccine was a failure in [[North America]] as there was not a statistically significant reduction of HIV infection within the study population.\n* AIDSVAX B/E was a component, along with ALVAC, of the [[RV 144]] vaccine trial in Thailand that showed partial efficacy in preventing HIV. The AIDSVAX B/E and ALVAC vaccines targeted the [[gp120]] part of the HIV envelope. The study involved 16,395 participants who did not have HIV infection, 8197 of whom were given treatment consisting of two experimental vaccines targeting [[Subtypes of HIV|HIV types B and E]] that are prevalent in Thailand, while 8198 were given a placebo. The participants were tested for HIV every six months for three years. After three years, the vaccine group had HIV infection rates reduced by about 30% compared with those in the placebo group. However, after taking into account the seven people who already had HIV before getting vaccinated (two in the placebo group, five in the vaccine group) the difference was 26%.<ref name="Rerks-Ngarm2009">{{cite journal | vauthors = Rerks-Ngarm S, Pitisuttithum P, Nitayaphan S, Kaewkungwal J, Chiu J, Paris R, Premsri N, Namwat C, de Souza M, Adams E, Benenson M, Gurunathan S, Tartaglia J, McNeil JG, Francis DP, Stablein D, Birx DL, Chunsuttiwat S, Khamboonruang C, Thongcharoen P, Robb ML, Michael NL, Kunasol P, Kim JH | display-authors = 6 | title = Vaccination with ALVAC and AIDSVAX to prevent HIV-1 infection in Thailand | journal = The New England Journal of Medicine | volume = 361 | issue = 23 | pages = 2209\u201320 | date = December 2009 | pmid = 19843557 | doi = 10.1056/NEJMoa0908492 }}</ref> It was discovered that participants receiving vaccines in the RV 144 trial who produced [[Immunoglobulin G|IgG]] antibodies against the [[V2 loop]] of the [[Envelope glycoprotein GP120|HIV outer envelope]] were 43% less likely to become infected than those who did not, while [[IgA]] production was associated with a 54% greater risk of infection than those who did not produce the antibodies (but not worse than placebo). Viruses collected from vaccinated participants had mutations in the V2 region. Tests of a vaccine for [[Simian immunodeficiency virus|SIV]] in monkeys found greater resistance to SIV in animals producing antibodies against this region. Therefore, further research is expected to focus on creating vaccines designed to provoke an IgG reaction against the V2 loop.<ref>{{cite journal | title = Clues emerge to explain first successful HIV vaccine trial | journal = Nature | first = Ewen | last = Callaway | name-list-style = vanc | date=16 September 2011 | doi = 10.1038/news.2011.541 }}</ref>\n* In 2020, the phase IIb-III trial {{visible anchor|[[HVTN 702]]}}/"Uhambo" found that ALVAC/gp120/MF59 vaccinations were safe, and caused no harm, but had no efficacy in HIV prevention in [[South Africa]]. Vaccinations with the Uhambo vaccine regimen began late 2016 and stopped early 2020.<ref>{{cite web |url=https://www.nih.gov/news-events/news-releases/experimental-hiv-vaccine-regimen-ineffective-preventing-hiv |title=Experimental HIV vaccine regimen ineffective in preventing HIV |publisher=NIH |date=3 February 2020 |access-date=4 February 2020 |archive-date=4 February 2020 |archive-url=https://web.archive.org/web/20200204053128/https://www.nih.gov/news-events/news-releases/experimental-hiv-vaccine-regimen-ineffective-preventing-hiv |url-status=live }}</ref>\n* In 2020, the Ad26.Mos4.HIV plus adjuvanted clade C gp140 vaccine regimen entered a phase III trial called HVTN 706/"Mosaico". The regimen is a combination of an adenovirus vector vaccine engineered against multiple global strains of HIV, and a protein vaccine.<ref>{{cite web|url=https://www.nih.gov/news-events/news-releases/nih-partners-launch-hiv-vaccine-efficacy-trial-americas-europe|title=NIH and partners to launch HIV vaccine efficacy trial in the Americas and Europe|last=15 July 2019|date=2019-07-15|publisher=[[National Institutes of Health]]|access-date=23 July 2019|archive-date=23 July 2019|archive-url=https://web.archive.org/web/20190723131154/https://www.nih.gov/news-events/news-releases/nih-partners-launch-hiv-vaccine-efficacy-trial-americas-europe|url-status=live}}</ref>\n''Therapeutic HIV vaccines''\n\nNo therapeutic HIV vaccine candidates have reached phase 3 testing yet."}},
{"article_title": "Mercury-in-glass thermometer", "pageid": "150245", "revid": "1062777251", "timestamp": "2021-12-30T13:16:23Z", "history_paths": [["Mercury-in-glass thermometer --- Introduction ---", "History"]], "categories": ["thermometers", "meteorological instrumentation and equipment", "dutch inventions", "mercury (element)", "science and technology in the dutch republic", "1714 introductions"], "heading_tree": {"Mercury-in-glass thermometer --- Introduction ---": {"History": {}, "Maximum thermometer": {}, "Maximum minimum thermometer": {}, "Physical properties": {}, "Phase-out": {"List of countries with regulations or recommendations on mercury thermometers": {"Argentina": {}, "Austria": {}, "Philippines": {}, "United Kingdom": {}, "United States": {}}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Mercury-in-glass thermometer --- Introduction ---|History": "[[Image:Quicksilvertermometer Osaby.JPG|thumb|upright|A large mercury in glass thermometer.]]\n{{See also|Liquid-in-glass thermometer|Timeline of temperature and pressure measurement technology}}\nThe thermometer was used by the originators of the [[Fahrenheit]] and [[Celsius]] scales.\n\n[[Anders Celsius]], a Swedish scientist, devised the Celsius scale, which was described in his publication ''The origin of the Celsius temperature scale'' in 1742.\n\nTo define his scale Celsius used two fixed temperature points: the temperature of melting ice and the temperature of boiling water, both under atmospheric pressure of the [[standard atmospheric pressure|standard atmosphere]]. This wasn't a new idea, since [[Isaac Newton]] was already working on something similar. The distinction of  Celsius was to use the condition of melting and not that of freezing. The experiments for reaching a good calibration of his thermometer lasted for 2 winters. By performing the same experiment over and over again, he discovered that ice always melted at the same calibration mark on the thermometer. He found a similar fixed point in the calibration of boiling water to [[water vapor|water vapour]] (when this is done to high precision, a variation will be seen with atmospheric pressure; Celsius noted this).  At the moment that he removed the thermometer from the vapour, the mercury level climbed slightly. This was related to the rapid cooling (and contraction) of the glass.\n\nWhen Celsius decided to use his own temperature scale, he originally defined his scale "upside-down", i.e. he chose to set the boiling point of pure water at <!--DON'T CHANGE THIS. It's supposed to be the wrong way around. Please check the source. Thanks-->0 \u00b0C (212 \u00b0F) and the freezing point at 100 \u00b0C (32 \u00b0F).<ref>{{cite web |title=Anders Celsius 1701\u20131744 |work=Astronomical Observatory: History |publisher=Uppsala University |url=http://www.astro.uu.se/history/Celsius_eng.html }}</ref> One year later, Frenchman [[Jean-Pierre Christin]] proposed to invert the scale with the freezing point at {{convert|0|C}} and the boiling point at {{convert|100|C}}.<ref>{{cite book |first=Jacqueline |last=Smith |chapter=Appendix I: Chronology |title=The Facts on File Dictionary of Weather and Climate |chapter-url=https://books.google.com/books?id=lAfa1orgvwQC&pg=PA246 |year=2009 |publisher=Infobase Publishing |isbn=978-1-4381-0951-0 |pages=246 |quote=1743 Jean-Pierre Christin inverts the fixed points on Celsius' scale, to produce the scale used today.}}</ref> He named it centigrade (100 steps).\n\nFinally, Celsius proposed a method of calibrating a thermometer:\n# Place the cylinder of the thermometer in melting ice made of pure water and mark the point where the fluid in the thermometer stabilises.  This point is the freeze/thaw point of water.\n# In the same manner mark the point where the fluid stabilises when the thermometer is placed in boiling water vapour.\n# Divide the length between the two marks into 100 equal parts.\n\nThese points are adequate for approximate calibration, but both the freezing and boiling points of water vary with atmospheric pressure. Later thermometers that used a liquid other than mercury also gave slightly different temperature readings. In practice, these variations were very slight and remained close to the thermodynamic temperature, once the latter was discovered. These issues were explored experimentally with the [[gas thermometer]]. Until the discovery of true thermodynamic temperature, the mercury thermometer usually ''defined'' the temperature. \n\nModern thermometers are often calibrated using the [[triple point]] of water instead of the freezing point; the triple point occurs at 273.16 kelvins (K), 0.01 \u00b0C."}},
{"article_title": "Hand fan", "pageid": "152643", "revid": "1061043472", "timestamp": "2021-12-19T08:17:38Z", "history_paths": [["Hand fan --- Introduction ---", "History"]], "categories": ["articles containing video clips", "ancient egyptian technology", "ancient greek technology", "chinese culture", "chinese inventions", "cooling technology", "greek inventions", "ventilation fans", "fashion accessories", "hand tools", "japanese culture", "japanese inventions"], "heading_tree": {"Hand fan --- Introduction ---": {"History": {"Africa": {}, "Europe": {}, "Early Modern period": {}, "East Asia": {"Chinese hand fan": {}, "Japanese hand fan": {}, "Korea hand fan": {}}, "Modern day": {"Drag subculture": {}}}, "Categories": {}, "Gallery": {}, "See also": {"Use in dance": {}, "Use as weapons": {}, "Use in comedy": {}, "Use in politics": {}, "Museums": {}}, "References": {"Sources": {}, "Books": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Hand fan --- Introduction ---|History": "Hand fans originated about 4000 years ago in Egypt. Egyptians viewed them as sacred objects, and the tomb of [[Tutankhamun]] contained two elaborate hand fans.<ref>{{Cite web|title=Online Exhibit - A Brief History of the Hand Fan|url=https://web.ics.purdue.edu/~salvo/@SEA/exhibit/history.asp|access-date=2021-09-26|website=web.ics.purdue.edu}}</ref>\n\n {{Further|European hand fans in the 18th century}}\n[[File:Milano - Museo archeologico - Vaso apulo con Eros - Foto di Giovanni Dall'Orto - 25-7-2003.jpg|thumb|left|[[Eros]] offering a fan and a mirror to a lady. [[Ancient Greece|Ancient Greek]] [[amphora]] from [[Apulia]], Archaeological Museum in Milan, Italy]]\n[[File:Folding Fan LACMA M.67.8.115 (1 of 2).jpg|thumb|Folding fan from France {{circa|1850}}]]\n[[File:Anderson Sophie Ready For The Ball.jpg|left|thumb|''Ready For The Ball'' by [[Sophie Anderson]]]]\n[[File:Mujer con abanico y manto - Ulpiano Checa.JPG|thumbnail|Lady with fan and shawl. [[Ulpiano Checa]]]]\n\nArchaeological ruins and ancient texts show that the hand fan was used in [[ancient Greece]] at least from the 4th century BC and was known as a {{transl|el|rhipis}} ({{lang-el|\u1fe5\u03b9\u03c0\u03af\u03c2}}).<ref>[https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dr%28ipi%2Fs \u1fe5\u03b9\u03c0\u03af\u03c2], Henry George Liddell, Robert Scott, ''A Greek-English Lexicon'', on Perseus</ref>\n\nChristian Europe's earliest known fan was the [[flabellum]] (ceremonial fan), which dates from the 6th century. It was used during services to drive insects away from the consecrated bread and wine. Its use died out in western Europe, but continues in the [[Eastern Orthodox Church|Eastern Orthodox]] and [[Ethiopian Church]]es.\n\nHand fans were absent from [[Europe]] during the [[High Middle Ages]] until they were reintroduced in the 13th and 14th centuries. Fans from the [[Middle East]] were brought by [[The Crusades|Crusader]]s, and refugees from the [[Byzantine Empire]]. Portuguese traders brought them from [[East Asia]] (China and Japan) in the 16th century, and fans became generally popular.\n\nThe fan became especially popular in Spain, where flamenco dancers used the fan and extended its use to the nobility.\n\nEuropean fan-makers have introduced more modern designs and have enabled the hand fan to work with modern fashion.\n\n In the 17th century the folding fan, and its attendant [[semiotic]] culture, were introduced from Japan. Simpler fans were developed in China, Greece, and Egypt. East Asian (Japanese and Chinese) imports became popular in Europe. These fans are particularly well displayed in the portraits of the high-born women of the era. Queen Elizabeth I of England can be seen to carry both folding fans decorated with pom poms on their guardsticks as well as the older style rigid fan, usually decorated with feathers and jewels. These rigid style fans often hung from the skirts of ladies, but of the fans of this era it is only the more exotic folding ones which have survived. Those folding fans of the 15th century found in museums today have either leather leaves with cut out designs forming a lace-like design or a more rigid leaf with inlays of more exotic materials like mica. One of the characteristics of these fans is the rather crude bone or ivory sticks and the way the leather leaves are often slotted onto the sticks rather than glued as with later folding fans. Fans made entirely of decorated sticks without a fan 'leaf' were known as {{lang|fr|bris\u00e9}} fans. However, despite the relative crude methods of construction folding fans were at this era high status, exotic items on par with elaborate gloves as gifts to royalty.\n\nIn the 17th century the rigid fan which was seen in portraits of the previous century had fallen out of favour as folding fans gained dominance in Europe. Fans started to display well painted leaves, often with a religious or classical subject. The reverse side of these early fans also started to display elaborate flower designs. The sticks are often plain ivory or tortoiseshell, sometimes inlaid with gold or silver pique work. The way the sticks sit close to each other, often with little or no space between them is one of the distinguishing characteristics of fans of this era.\n\nIn 1685 the [[Edict of Nantes]] was revoked in [[France]]. This caused large scale immigration from France to the surrounding Protestant countries (such as England) of many fan craftsman. This dispersion in skill is reflected in the growing quality of many fans from these non-French countries after this date.\n\nIn the 18th century, fans reached a high degree of artistry and were being made throughout Europe often by specialized craftsmen, either in leaves or sticks. Folded fans of [[silk]], or [[parchment]] were decorated and painted by artists. Fans were also imported from China by the East India Companies at this time. Around the middle 18th century, inventors started designing mechanical fans. Wind-up fans (similar to wind-up clocks) were popular in the 18th century. In the 19th century in the [[Western world|West]], European fashion caused fan decoration and size to vary.\n[[File:Pinayavatar.jpg|thumb|A [[Filipino people|Filipina]] in [[baro't saya|traditional attire]] with an ''[[abaniko]]'' folding fan (c. 1875) which played a large part in courtship etiquette in the colonial [[Philippines]]<ref name="Lazatin">{{cite news |last1=Lazatin |first1=Hannah |title=The Secret Messages Filipinas Used to Send With Their Abanikos |url=https://www.esquiremag.ph/the-good-life/what-she-wants/casa-mercedes-language-of-fans-a00184-20180528-lfrm |access-date=17 July 2021 |work=Esquire |date=28 May 2018}}</ref>]] \nIt has been said that in the courts of England, Spain and elsewhere fans were used in a more or less secret, unspoken code of messages.<ref>{{cite web|url=http://jeroenarendsen.nl/2006/06/indecent-fan-proposals_19/|title=Indecent Fan Proposals - A Nice Gesture by Jeroen Arendsen|work=jeroenarendsen.nl|date=19 June 2006}}</ref> These fan languages were a way to cope with the restricting social etiquette. However, modern research has proved that this was a marketing ploy developed in the 19th century<ref>FANA Journal, spring 2004, Fact & Fiction about the language of the fan by J.P. Ryan</ref> - one that has kept its appeal remarkably over the succeeding centuries. This is now used for marketing by fan makers like [[Cussons & Sons & Co. Ltd]] who produced a series of advertisements in 1954 showing "the language of the fan" with fans supplied by the well known French fan maker [[Duvelleroy]].{{Citation needed|date=January 2010}}\n\nThe rigid or screen fan ({{lang|fr|\u00e9ventail a \u00e9cran}}) became also fashionable during the 18th and 19th century. They never reached the same level of popularity as the easy to carry around, folding fans which became almost an integrated part of women's dress. The screen fan was mainly used inside the interior of the house. In 18th and 19th century paintings of interiors one sometimes sees one laying on a chimney mantle. They were mainly used to protect a woman's face against the glare and heat of the fire, to avoid getting {{lang|fr|"coup rose"}}, or ruddy cheeks from the heat. But probably not in the least it served to keep the heat from spoiling the carefully applied make-up which in those days was often wax-based. Until the 20th century houses were heated by open fires in chimneys or by stoves, and the lack of insulation made many a house very draughty and cold during winter. Therefore, any social or family gathering would be in close proximity to the fireplace.\n\nThe design of the screen fan is a fixed handle, most often made out of exquisitely turned (painted or guided) wood, fixed to a flat screen. The screen could be made out of silk stretched on a frame or thin wood, leather or papier mache. The surface is often exquisitely painted with scenes ranging from flowers and birds of paradise to religious scenes. At the end of the 19th century they disappeared when the need for them ceased to exist. During the 19th century names like the Birmingham-based firm of [[Jennens and Bettridge]] produced many papier-m\u00e2ch\u00e9 fans.\n\n  The oldest existing Chinese fans are a pair of woven [[bamboo]], wood or paper side-mounted fans from the 2nd century BC.<ref>{{cite web|url=http://www.aboutdecorativestyle.com/articles/history_fans.htm|title=articles - brief history of fans|work=aboutdecorativestyle.com}}</ref> The [[Chinese characters|Chinese character]] for "fan" ({{lang|zh|[[wikt:\u6247|\u6247]]}}) is ideogrammatically composed of the characters for 'door' ({{lang|zh|[[wikt:\u6236|\u6236]]}}) and 'feather' ({{lang|zh|[[wikt:\u7fbd|\u7fbd]]}}).\n\nSpecific concepts of status and gender were associated with types of fans in Chinese history. During the [[Song dynasty]], famous artists were often commissioned to paint fans. The Chinese dancing fan was developed in the 7th century. The Chinese form of the hand fan was a row of feathers mounted in the end of a handle. In later centuries, Chinese poems and four-word idioms were used to decorate fans, using Chinese calligraphy pens. In ancient China, fans came in various shapes and forms (such as in a leaf, oval or a half-moon shape), and were made in different materials such as silk, bamboo, and feathers.<ref>{{cite web|url=http://www.hand-fan.org/chinese_hand_fans.html|title=Chinese Hand Fans|work=hand-fan.org}}</ref> The invention of folding fan in Japan was later introduced to the Chinese in the 10th century.<ref>{{Cite book|last=Panati|first=Charles|url=https://www.worldcat.org/title/panatis-extraordinary-origins-of-everyday-things/oclc/962329974&referer=brief_results|title=Panati's extraordinary origins of everyday things|date=2016|isbn=978-0-7858-3437-3|language=English|oclc=962329974}}</ref><ref>{{Cite book|last=Qian|first=Gonglin|url=https://www.worldcat.org/title/chinese-fans-artistry-and-aesthetics/oclc/867778328&referer=brief_results|title=Chinese fans: artistry and aesthetics|date=2004|publisher=Long River Press|isbn=978-1-59265-020-0|location=San Francisco|language=English|oclc=867778328}}</ref>\n{{Gallery\n  |title = Chinese hand fans\n  |align = center\n  |File:Folding fan with daylilies, rocks, and a poem, painted by the Qianlong emperor for Empress Dowager Chongqing, China, 1762 AD, ink and color on paper, bamboo - Peabody Essex Museum - DSC07993.jpg|Folding fan painted by the Qianlong emperor for Empress Dowager Chongqing, China, 1762 AD.\n|File:Chen Hongshou, Appreciating Plums, detail.jpg|A portrait of a lady holding a rigid (oval) fan from the painting "Appreciating Plums", by Chinese artist [[Chen Hongshou]]\n  |File:Non electric fan aka solfjader.jpg|A typical commercially produced scented wood folding fan, featuring a drawing of the [[Great Wall of China]]\n  |File:Kongfu fan.jpg|Chinese foldable fans are also used in the performance of [[Kung Fu]]\n}}\n\n In ancient Japan, hand fans, such as oval and silk fans, were influenced greatly by Chinese fans.<ref>{{cite web|url=http://www.hand-fan.org/japanese_hand_fans.html|title=Japanese Hand Fans|work=hand-fan.org}}</ref> The earliest visual depiction of fans in Japan dates back to the 6th century AD, with burial tomb paintings showed drawings of fans. The folding fan was invented in Japan,<ref>{{Cite web|last=Nathan|first=Richard|date=17 April 2020|title=The First Portable Device Loved by Japan\u2019s Literati|url=https://www.redcircleauthors.com/news-and-views/the-first-portable-device-loved-by-japans-literati/|url-status=live|archive-url=|archive-date=|access-date=12 January 2021|website=Red Circle Authors}}</ref> with dates ranging from the 6th to 9th centuries.<ref name="Halsey & Friedman 1983">{{cite book|url=https://books.google.com/books?id=8LwJAAAAIAAJ&q=akomeogi&pg=PA556|title=Collier's encyclopedia: with bibliography and index|volume= 9|first1= William Darrach |last1=Halsey|first2= Emanuel |last2=Friedman |publisher= Macmillan Educational Co.|year= 1983|page=556|quote= In the 7th century the folding fan evolved, the earliest form of which was a court fan called the "Akomeogi", which had thirty-eight blades connected by a rivet; it had artificial flowers at the corners and twelve long, colored silk streamers.}}</ref><ref name=" Lipinski 1999">{{cite book|url=https://archive.org/details/newyorktimeshome00lipi|url-access=registration|title=The New York Times home repair almanac: a season-by-season guide for maintaining your home |first= Edward R. |last=Lipinski |publisher= Lebhar-Friedman Books|year= 1999 |isbn= 0-86730-759-5|quote= The Japanese developed the folding fan, the Akomeogi, during the sixth century. Portuguese traders introduced it to the west in the 16th century and soon both men and women throughout the continent adopted it.}}</ref><ref name="Qian 2000, p.12"/><ref name="Verschuer 2006" >{{cite book|url=https://books.google.com/books?id=tjTZAAAAIAAJ&q=%22folding+fan%22+%22Japanese+creation%22&pg=PA12|title=Across the perilous sea: Japanese trade with China and Korea from the seventh to the sixteenth centuries|first=Charlotte von |last=Verschuer |publisher= Cornell University|year= 2006 |isbn= 1-933947-03-9|page=72|quote= Another Japanese creation enjoyed great success among foreigners: the folding fans. It was invented in Japan in the eighth or ninth century, when only round and fixed (uchiwa) fans made of palm leaves were known. -- their usage had spread throughout China in antiquity. Two types of folding fans developed: one was made of cypress-wood blades bound by a thread (hiogi); the other had a frame with fewer blades which was covered in Japanese paper and folded in a zigzag patterns (kawahori-ogi).}}<br>"The paper fan was described by a thirteenth-century Chinese author, but well before that date {{lang|ja-Latn|Ch\u014dnen|italic=no}} had offered twenty wooden-bladed fans and two paper fans to the emperor of China."</ref> It was a court fan called the {{nihongo||\u8875\u6247|akomeogi}} after the court women's dress named {{transl|ja|akome}}.<ref name="Halsey & Friedman 1983"/><ref>{{cite web|url=http://kotobank.jp/word/%E8%A1%B5%E6%89%87|script-title=ja:\u8875\u6247|trans-title=Akomeogi|publisher=Mypedia|language=ja}}</ref> According to the {{transl|zh|Song Sui}} (History of Song), a Japanese monk {{nihongo|Ch\u014dnen|[[:ja:\u3061\u3087\u3046\u7136]]/\u595d\u7136||938\uff0d1016}} offered the folding fans (twenty wooden-bladed fans {{nihongo||\u6867\u6247|hiogi}} and two paper fans {{nihongo||\u8759\u8760\u6247|kawahori-ogi}} to the emperor of China in 988.<ref name="Qian 2000, p.12">{{cite book|url=https://books.google.com/books?id=e2n9ta1D8DUC&q=Japanese+monk&pg=PA12|page=12|title=Chinese fans: artistry and aesthetics|first= Gonglin|last= Qian |publisher= Long River Press|year= 2000 |isbn= 1-59265-020-1|quote= The first folding fan arrived as a tribute that was brought to China by a Japanese monk in 988. Writings of both Japanese and Chinese scholars concerning the folding fan, which was believed to have been first invented in Japan, apparently suggest that it received its shape from the design of a bat's wing.}}</ref><ref name="Verschuer 2006"/><ref name="Julia & Alexander 1992" >{{cite book|url=https://books.google.com/books?id=vBPrAAAAMAAJ&q=Song+shu|title=\u014cgi: a history of the Japanese fan |first1= Julia|last1= Hutt|first2= H\u00e9l\u00e8ne |last2=Alexander |publisher= Dauphin Pub.|year= 1992 |isbn= 1-872357-08-3|page=14|quote= It was recorded in the Song Shu, the official history of the Chinese Song dynasty (960-1279), that in 988 a Japanese monk, Chonen, presented at court gifts of...}}<br>(Editor's note: Instead of Song Shu (\u5b8b\u66f8 ''[[Book of Song]]''), Song Sui (\u5b8b\u53f2, [[:zh:\u5b8b\u53f2|History of Song]]) is correct.)<br>"There are also numerous references to folding fans in the great classical literature of the Heian period (794-1185), in particular the Genji Monogatari (''The Tale of Genji'') by Murasaki Shikibu and the Makura no S\u014dshi (''The Pillow Book'') by Sei Sh\u014dnagon. Already by the end of tenth century, the popularity of folding fans was such that sumptuary laws were promulgated during Ch\u014dho era (999-1003) which restricted the decoration of both hiogi and paper folding fans."</ref>\n\nLater in the 11th century, Korean envoys brought along Korean folding fans which were of Japanese origin as gifts to Chinese court.<ref name=" Tsang 2002, p.10">{{cite book|url=https://books.google.com/books?id=xBTrAAAAMAAJ&q=korean|page=10|title=More than keeping cool: Chinese fans and fan painting |first= Ka Bo|last= Tsang |publisher= Royal Ontario Museum|year= 2002 |isbn= 0-88854-439-1|quote= Guo Ruoxu, for example, has included a short note about the folding fan in his Tuhua Jian Wen Zhi (''Records of Paintings Seen and Heard About'', 1074) It states that Korean envoys often brought along Korean folding fans as gifts. They were, Guo also pointed out, of Japanese origin.}}</ref> The popularity of folding fans was such that sumptuary laws were passed during [[Heian period]] which restricted the decoration of both {{transl|ja|hiogi}} and paper folding fans.<ref name="Julia & Alexander 1992"/><ref name=" Medley 1976">{{cite book|url= https://books.google.com/books?id=W3HrAAAAMAAJ&q=heian+origin+evidently\n|title=Chinese painting and the decorative style|first= Margaret |last=Medley |publisher= University of London School of Oriental and African Studies, Percival David Foundation of Chinese Art|year= 1976 |isbn=0-7286-0028-5|page=106|quote= In origin it was evidently Japanese, common already in the Heian period. A fragment of a late Heian folding-fan was excavated some decade ago at Takao-yama. Japanese fans were well known in China during the late eleventh century.}}</ref>\n\n{{Gallery\n  |title = Japanese hand fans\n  |align = center\n  |File:Uchiwa.jpg|Japanese rigid fan (''{{ill|uchiwa|ja|\u3046\u3061\u308f}}'')\n  |File:Japanes Fan (Hakusen).png|Japanese foldable fan ({{transl|ja|sensu}})\n  |File:Fan of Japanese Cypress ITUKUSHIMA shrine.JPG|Japanese foldable fan of late Heian period (12th century)\n  |File:Noh5.jpg|Noh performance at [[Itsukushima Shrine|Itsukushima]] Shrine\n}}\n\nThe earliest fans in Japan were made by tying thin stripes of {{transl|ja|[[Hinoki Cypress|hinoki]]}} (or Japanese cypress) together with thread. The number of strips of wood differed according to the person's rank. Later in the 16th century, Portuguese traders introduced it to the west and soon both men and women throughout the continent adopted it.<ref name=" Lipinski 1999"/> They are used today by [[Shinto]] priests in formal costume and in the formal costume of the Japanese court (they can be seen used by the Emperor and Empress during [[Enthronement of the Japanese Emperor|enthronement]] and marriage) and are brightly painted with long tassels. Simple Japanese paper fans are sometimes known as {{transl|ja|[[harisen]]}}.\n\nPrinted fan leaves and painted fans are done on a paper ground. The paper was originally handmade and displayed the characteristic watermarks. Machine-made paper fans, introduced in the 19th century, are smoother, with an even texture. Even today, [[geisha]] and {{transl|ja|[[maiko]]}} use folding fans in their fan dances as well.\n\nJapanese fans are made of paper on a bamboo frame, usually with a design painted on them. In addition to folding fans ({{transl|ja|\u014dgi}}),<ref>Nussbaum, Louis Fr\u00e9d\u00e9ric ''et al.'' (2005). "''\u014cgi''" in {{Google books|p2QnPijAEmEC|''Japan Encyclopedia,'' p. 738.|page=738}}</ref> the non-bending fans ({{lang|ja-Latn|uchiwa}}) are popular and commonplace.<ref>Nussbaum, "''Uchiwa,''" {{Google books|p2QnPijAEmEC| p. 1006.|page=1006}}</ref> The fan is primarily used for fanning oneself in hot weather. The {{transl|ja|uchiwa}} fan subsequently spread to other parts of Asia, including Burma, Thailand, Cambodia and Sri Lanka, and such fans are still used by Buddhist monks as "ceremonial fans".<ref>{{cite web|title=Buddhist Monks Ceremonial Fans|url=http://www.thebuddhasface.co.uk/buddhist-monks-ceremonial-fans-119-c.asp|url-status=dead|archive-url=https://web.archive.org/web/20130423045844/http://www.thebuddhasface.co.uk/buddhist-monks-ceremonial-fans-119-c.asp|archive-date=April 23, 2013|access-date=2017-10-27|publisher=Thebuddhasface.co.uk}}</ref>\n\nFans were also used in the military as a way of sending signals on the field of battle. However, fans were mainly used for social and court activities. In Japan, fans were variously used by warriors as a form of weapon, by actors and dancers for performances, and by children as a toy.\n\nTraditionally, the rigid fan (also called fixed fan) was the most popular form in China,<ref>{{cite encyclopedia|url=http://www.britannica.com/EBchecked/topic/201415/fan|title=fan - decorative arts|encyclopedia=Encyclop\u00e6dia Britannica}}</ref> although the folding fan came into popularity during the [[Ming Dynasty]] between the years of 1368 and 1644, and there are many beautiful examples of these folding fans still remaining.<ref>ChinesePod Weekly, [http://chinesepod.com/blog/Chinese%2BFans%253A%2BMore%2BThan%2BKeeping%2BCool%2B%255B%2BChinesePod%2BWeekly%2B%255D/1027 Chinese Fans: More Than Keeping Cool] {{webarchive|url=https://web.archive.org/web/20121113103306/http://chinesepod.com/blog/Chinese%2BFans%253A%2BMore%2BThan%2BKeeping%2BCool%2B%255B%2BChinesePod%2BWeekly%2B%255D/1027 |date=2012-11-13 }}</ref>\n\nThe {{transl|ja|mai ogi}} (or Japanese dancing fan) has ten sticks and a thick paper mount showing the family crest, and Japanese painters made a large variety of designs and patterns. The slats, of [[ivory]], [[bone]], [[mica]], [[pearl|mother of pearl]], [[sandalwood]], or [[tortoiseshell material|tortoise shell]], were carved and covered with [[paper]] or [[Textile|fabric]]. Folding fans have "montures" which are the sticks and guards, and the leaves were usually painted by craftsmen. Social significance was attached to the fan in the Far East as well, and the management of the fan became a highly regarded feminine art. Fans were even used as a weapon - called the [[iron fan]], or {{transl|ja|[[tessen]]}} in Japanese.\n\n[[File:GinfukurinGunbai.jpg|thumb|right|A {{transl|ja|gunbai-uchiwa}}, the military leader's fan|168x168px]] \nSee also, the {{transl|ja|[[gunbai]]}}, a military leader's fan (in old Japan); used in the modern day as an umpire's fan in sumo wrestling, it is a type of Japanese war fan, like the {{transl|ja|tessen}}.\n\n Every Dano (May 5th of the lunar calendar) when the heat began, there was a custom in which the king distributed hand fan to vassal. Vassal, who received a hand pan from the king, did an ink-and-wash painting and handed out white fans to his elders and the indebted people, which has made the practice of exchanging hand fan widely popular. These cultural factors also contributed to the creation of various types of hand fan in Korea.\n\n {{more citations needed|section|date=December 2020}}\nModern day hand fans are less popular than their ancestors but are still in use by many.\n\n A large group that continues to use folding hand fans for cultural and fashion use are [[drag queens]]. Stemming from ideas of imitating and appropriating cultural ideas of excess, wealth, status and elegance, large folding hand fans, sometimes {{convert|12|in|cm}} or more in radius, are used to punctuate speech, as part of performances, or as accessories to an outfit. Fans may have phrases taken from the lexicon of drag and [[LGBTQ+]] culture written on them, and may be decorated in other ways, such as the addition of sequins or tassels.\n\nFolding fans are often used to emphasize a point in a person's speech, rather than for express use of fanning ones self. A person might harshly snap open the fan when engaging in 'throwing shade' on (comically insulting) another person, creating a loud snapping noise that punctuates the insult. Drag dance numbers also utilise larger hand fans as a way to add flair and as a prop, used to emphasise movements in the dance.\n\nPopular drag comedy webshow [[UNHhhh]] has used folding fans as a point of humour, with the sound made by a folding fan unfolding coined [[onomatopoeia|onomatopoeically]] as a "thworp" by the editors."}},
{"article_title": "BESK", "pageid": "152701", "revid": "1045326676", "timestamp": "2021-09-20T00:54:20Z", "history_paths": [["BESK --- Introduction ---"], ["BESK --- Introduction ---", "Usage"]], "categories": ["ias architecture computers", "vacuum tube computers", "1950s computers", "science and technology in sweden"], "heading_tree": {"BESK --- Introduction ---": {"Performance": {}, "Usage": {}, "Trivia": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"BESK --- Introduction ---": "{{short description|Sweden's first electronic computer}}\n{{Other uses|Besk (disambiguation){{!}}Besk}}\n{{more citations needed|date=September 2012}}\n\n[[File:BESK-1.jpg|thumb|BESK control panel]]\n[[File:BESKmemories.jpg|thumb|Drum memory (bottom) and core memory (upper right) for the BESK computer]]\n\n'''BESK''' (''Bin\u00e4r Elektronisk SekvensKalkylator'', [[Swedish language|Swedish]] for "Binary Electronic Sequence Calculator") was [[Sweden]]'s first electronic [[computer]], using [[vacuum tube]]s instead of [[relay]]s. It was developed by ''[[Matematikmaskinn\u00e4mnden]]'' ([[Swedish Board for Computing Machinery]]) and for a short time it was the fastest computer in the world. The computer was completed in 1953<ref>{{Cite book|url=https://books.google.com/books?id=NQEpEyeIFyEC&q=%22besk%22+1953&pg=PA177|title=The Digital Flood: The Diffusion of Information Technology Across the U.S., Europe, and Asia|last=Cortada|first=James W.|date=2012-09-27|publisher=OUP USA|isbn=9780199921553|pages=177|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=Z_I0TQbgmY4C&q=%22besk%22+1953&pg=PA426|title=History of Nordic Computing 3: Third IFIP WG 9.7 Conference, HiNC3, Stockholm, Sweden, October 18-20, 2010, Revised Selected Papers|last1=Impagliazzo|first1=John|last2=Lundin|first2=Per|last3=Wangler|first3=Benkt|date=2011-09-29|publisher=Springer Science & Business Media|isbn=9783642233142|pages=426|language=en}}</ref><ref>{{cite journal|title=COMPUTERS, OVERSEAS: 1. Besk (Swedish Board For Computing Machinery, Stockholm, Sweden)|journal=Digital Computer Newsletter|date=Jul 1955|volume=7|issue=3|page=10|url=http://www.dtic.mil/docs/citations/AD0694617|language=en}}</ref> and in use until 1966. The technology behind BESK was later continued with the [[transistor]]ized [[FACIT EDB]] and FACIT EDB-3 machines, both software compatible with BESK. Non-compatible machines highly inspired by BESK were [[SMIL (computer)|SMIL]] made for the [[University of Lund]], ''SAABs r\u00e4kneautomat'' [[SARA (computer)|SARA]], "SAAB's calculating machine",  and [[DASK]] made in [[Denmark]].\n\nBESK was developed by the [[Swedish Board for Computing Machinery]] (Matematikmaskinn\u00e4mnden) a few years after the mechanical relay computer [[BARK (computer)|BARK]] (Bin\u00e4r Aritmetisk Rel\u00e4-Kalkylator, Swedish for "Binary Arithmetic Relay Calculator"). The team was initially led by [[Conny Palm]], who died in December 1951, after which [[Stig Com\u00e9t]] took over. The hardware was developed by [[Erik Stemme]]. [[G\u00f6sta Neovius]] and [[Olle Karlqvist]] were responsible for architecture and instruction set. It was closely modeled on the [[IAS machine]] for which the design team had retrieved drawings during a scholarship to [[Institute for Advanced Study|Institute for Advanced Study (IAS)]] and [[Massachusetts Institute of Technology]], U.S.\n\nDuring the development of the BESK magnetic [[drum memory]], [[Olle Karlqvist]] discovered a magnetic phenomenon, which has been called the [[Karlqvist gap]].\n\n BESK was a 40-bit machine; it could perform an addition in 56 \u03bcs and a multiplication took 350 \u03bcs. The [[electrostatic]] memory could store 512 words. The instruction length was 20 bits, so each word could store two instructions. BESK contained 2400 "radio tubes" ([[vacuum tube]]s) and 400 [[germanium]] [[diode]]s (so it was partly [[Solid state (electronics)|solid state]]). The power consumption was 15 [[kilovolt-ampere|kVA]].\n\nInitially an average runtime of 5 minutes was achieved before hardware problems appeared. In 1954 the system became more stable. Breakpoints were introduced to allow software restart after hardware failures.\n\nOriginally BESK had a British [[Williams tube]] 512 word x 40 bit memory based on 40 cathode tubes, and eight spare tubes. The memory was from the beginning found to be insufficient and [[Carl-Ivar Bergman]] was given just a few weeks to build and install a [[ferrite core memory]] in 1956. To get finished before the deadline they hired housewives with knitting experience to make the memory. One of the new memory bits did not work at first, but it was easily cut out and replaced.\n\n BESK was inaugurated on 1 April 1954 and handled weather data for [[Carl-Gustaf Rossby]] and the [[Swedish Meteorological and Hydrological Institute]], statistics for the telecommunications service provider [[Televerket (Sweden)|Televerket]], wing profiles for the attack aircraft [[Saab Lansen]], and road profiles for the road authority [[V\u00e4gverket]]. During the nights [[Swedish National Defence Radio Establishment]] (FRA) used BESK for cracking encryption of radio messages (by Per-Erik Persson ''et al.''). BESK was also used for [[calculation]]s for the [[Studsvik|Swedish nuclear energy industry]], for example [[Monte Carlo simulation]]s of [[neutron spectrum]] (by Per-Erik Persson ''et al.''), and for the [[Swedish nuclear weapon program]]{{Citation needed|date=May 2010}}, but most of those calculations were done by [[Siffermaskinen i Lund|SMIL]]. In 1957 [[Hans Riesel]] used BESK to discover a [[Mersenne prime]] with 969 digits - the largest prime known at the time.\n\n[[Saab Group|SAAB]] rented computer time on the BESK to (probably, much was secret) make calculations of the strength of the [[Saab Lansen]] attack aircraft. In the fall of 1955 SAAB thought the capacity was insufficient and started working on ''SAABs r\u00e4kneautomat'' [[SARA (computer)|SARA]], "SAAB's calculating machine",  which was going to be twice as fast as BESK. Some former SARA employees went to [[Facit]] and worked with the [[FACIT EDB]].\n\nIn the spring of 1956, eighteen of the BESK developers were hired by office equipment manufacturer [[Facit]] and housed in an office at Karlav\u00e4gen 62 in Stockholm, where they started to build copies of BESK called Facit EDB (models 1, 2, and 3), led by Carl-Ivar Bergman. A total of nine machines were built, of which four were used internally by Facit Electronics and five were sold to customers. On 1 July 1960 Facit Electronics, then with 135 employees, moved to [[Solna Municipality|Solna]], just north of Stockholm.\n\nIn 1960 BESK was used to create an animation of a car driving down a planned highway from the driver's perspective. This was one of the earliest computer animations ever made. The short clip was broadcast on Swedish national television on 9 November 1961.<ref>{{Cite news|url=https://www.tekniskamuseet.se/lar-dig-mer/kommunikation-och-media/datorhistoriska-nedslag/svensk-datorhistoria-1960-talet/|title=Svensk datorhistoria - 1960-talet - Tekniska museet|work=Tekniska museet|access-date=2017-11-16|others=[https://translate.google.com/translate?hl=en&sl=sv&tl=en&u=https%3A%2F%2Fwww.tekniskamuseet.se%2Flar-dig-mer%2Fkommunikation-och-media%2Fdatorhistoriska-nedslag%2Fsvensk-datorhistoria-1960-talet%2F Google translation]|language=sv-SE|archive-url=https://web.archive.org/web/20170103001844/https://www.tekniskamuseet.se/lar-dig-mer/kommunikation-och-media/datorhistoriska-nedslag/svensk-datorhistoria-1960-talet/|archive-date=2017-01-03|url-status=dead}}</ref>\n\n "Besk" is Swedish for the taste "bitter". [[B\u00e4sk]] is also the name of a traditional [[bitters]] made from distilled alcohol seasoned with the herb ''[[Artemisia absinthium]] L.'' local to the province of [[Sk\u00e5ne]], in which Lund is located. Reportedly this was an intentional and unnoticed pun after officials denied usage of the name ''CONIAC'' ([[Conny Palm|Conny [Palm]]] Integrator And Calculator, compare [[Cognac]] and [[ENIAC]]) for the predecessor BARK.\n\n *[[BARK (computer)|BARK]] - Bin\u00e4r Aritmetisk Rel\u00e4-Kalkylator - Sweden's first computer.\n*[[Elsa-Karin Boestad-Nilsson]], a programmer on BARK and BESK\n*[[SMIL (computer)|SMIL]] - SifferMaskinen I Lund (The Number Machine in Lund)\n*[[History of computing hardware]]\n*[[List of vacuum tube computers]]\n\n {{reflist}}\n\n {{Commons category|BESK}}\n* [https://www.tekniskamuseet.se/lar-dig-mer/datorhistoria/svensk-datorhistoria-1960-talet/ Datorhistoriska nedslag] (in Swedish), [https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=https%3A%2F%2Fwww.tekniskamuseet.se%2Flar-dig-mer%2Fkommunikation-och-media%2Fdatorhistoriska-nedslag%2F&edit-text= Google translation]\n* [http://www.treinno.se/pers/okq/besk.htm BESK Bin\u00e4r Elektronisk Sekvens Kalkylator] (in Swedish), [https://translate.google.com/translate?hl=en&sl=sv&tl=en&u=http%3A%2F%2Fwww.treinno.se%2Fpers%2Fokq%2Fbesk.htm Google translation]\n* [http://user.it.uu.se/~foy/Documents/BESK_programmers_manual_rev_2a_1958-05-02_swedish.pdf BESK programmers manual] (in Swedish)\n*{{cite journal|title=ARTICLES: Some Computer Developments In Sweden|journal=Computers and Automation|date=Nov 1959|volume=8|issue=11|pages=16, 18, 20, 22|url=http://www.bitsavers.org/magazines/Computers_And_Automation/195911.pdf|access-date=2020-09-05}}\n\n{{DEFAULTSORT:Besk}}", "BESK --- Introduction ---|Usage": "BESK was inaugurated on 1 April 1954 and handled weather data for [[Carl-Gustaf Rossby]] and the [[Swedish Meteorological and Hydrological Institute]], statistics for the telecommunications service provider [[Televerket (Sweden)|Televerket]], wing profiles for the attack aircraft [[Saab Lansen]], and road profiles for the road authority [[V\u00e4gverket]]. During the nights [[Swedish National Defence Radio Establishment]] (FRA) used BESK for cracking encryption of radio messages (by Per-Erik Persson ''et al.''). BESK was also used for [[calculation]]s for the [[Studsvik|Swedish nuclear energy industry]], for example [[Monte Carlo simulation]]s of [[neutron spectrum]] (by Per-Erik Persson ''et al.''), and for the [[Swedish nuclear weapon program]]{{Citation needed|date=May 2010}}, but most of those calculations were done by [[Siffermaskinen i Lund|SMIL]]. In 1957 [[Hans Riesel]] used BESK to discover a [[Mersenne prime]] with 969 digits - the largest prime known at the time.\n\n[[Saab Group|SAAB]] rented computer time on the BESK to (probably, much was secret) make calculations of the strength of the [[Saab Lansen]] attack aircraft. In the fall of 1955 SAAB thought the capacity was insufficient and started working on ''SAABs r\u00e4kneautomat'' [[SARA (computer)|SARA]], "SAAB's calculating machine",  which was going to be twice as fast as BESK. Some former SARA employees went to [[Facit]] and worked with the [[FACIT EDB]].\n\nIn the spring of 1956, eighteen of the BESK developers were hired by office equipment manufacturer [[Facit]] and housed in an office at Karlav\u00e4gen 62 in Stockholm, where they started to build copies of BESK called Facit EDB (models 1, 2, and 3), led by Carl-Ivar Bergman. A total of nine machines were built, of which four were used internally by Facit Electronics and five were sold to customers. On 1 July 1960 Facit Electronics, then with 135 employees, moved to [[Solna Municipality|Solna]], just north of Stockholm.\n\nIn 1960 BESK was used to create an animation of a car driving down a planned highway from the driver's perspective. This was one of the earliest computer animations ever made. The short clip was broadcast on Swedish national television on 9 November 1961.<ref>{{Cite news|url=https://www.tekniskamuseet.se/lar-dig-mer/kommunikation-och-media/datorhistoriska-nedslag/svensk-datorhistoria-1960-talet/|title=Svensk datorhistoria - 1960-talet - Tekniska museet|work=Tekniska museet|access-date=2017-11-16|others=[https://translate.google.com/translate?hl=en&sl=sv&tl=en&u=https%3A%2F%2Fwww.tekniskamuseet.se%2Flar-dig-mer%2Fkommunikation-och-media%2Fdatorhistoriska-nedslag%2Fsvensk-datorhistoria-1960-talet%2F Google translation]|language=sv-SE|archive-url=https://web.archive.org/web/20170103001844/https://www.tekniskamuseet.se/lar-dig-mer/kommunikation-och-media/datorhistoriska-nedslag/svensk-datorhistoria-1960-talet/|archive-date=2017-01-03|url-status=dead}}</ref>"}},
{"article_title": "BARK (computer)", "pageid": "152702", "revid": "1053962853", "timestamp": "2021-11-07T05:25:32Z", "history_paths": [["BARK (computer) --- Introduction ---", "History"]], "categories": ["one-of-a-kind computers", "electro-mechanical computers", "science and technology in sweden"], "heading_tree": {"BARK (computer) --- Introduction ---": {"History": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"BARK (computer) --- Introduction ---|History": "BARK was developed by ''[[Matematikmaskinn\u00e4mnden]]'' ([[Swedish Board for Computing Machinery]]) a few years before [[BESK]]. The machine was built with 8,000 standard telephone relays, 80 km of cable and with 175,000 soldering points. Programming was done by [[plugboard]].{{sfn|Mathematics of Computation|1951|p=32|ps=: "No instructions are given to the machine from tapes or similar devices; all programs are physically realized by the plugged connections."}}<ref>{{Cite book|url=https://books.google.com/books?id=K9_LsJBCqWMC&q=BARK+computer+1950&pg=PA129|title=A Vast Machine: Computer Models, Climate Data, and the Politics of Global Warming|last=Edwards|first=Paul N.|date=2010-03-12|publisher=MIT Press|isbn=9780262290715|pages=129|language=en}}</ref><ref>{{Cite journal|date=1950-01-01|title=12. Digital Computers in Sweden|url=http://www.dtic.mil/docs/citations/AD0694596|journal=Digital Computer Newsletter|language=en|volume=2|issue=1|pages=4}}</ref> It was completed in February 1950<ref>{{Cite book|url=https://books.google.com/books?id=jCSpiVBH5W0C&q=bark&pg=PA350|title=The Computer from Pascal to von Neumann|last=Goldstine|first=Herman H.|date=2008-09-02|publisher=Princeton University Press|isbn=978-1400820139|pages=350|language=en}}</ref><ref>{{cite book|url=https://archive.org/details/bitsavers_onrASurveyomputers1953_8778395|title=A survey of automatic digital computers|last1=Research|first1=United States Office of Naval|date=1953|publisher=Office of Naval Research, Dept. of the Navy|page=[https://archive.org/details/bitsavers_onrASurveyomputers1953_8778395/page/n13 8]|language=en}}</ref> at a cost of 400,000 [[Swedish krona|Swedish kronor]] (less than $100,000),<ref>{{Cite journal|date=1950-05-01|title=13. BARK Computer, Sweden|url=http://www.dtic.mil/docs/citations/AD0694597|journal=Digital Computer Newsletter|language=en|volume=2|issue=2|pages=4}}</ref> became operational on April 28, 1950, and was taken offline on September 22, 1954. The engineers on the team led by [[Conny Palm]] were Harry Freese, G\u00f6sta Neovius, Olle Karlqvist, Carl-Erik Fr\u00f6berg, G. Kellberg, Bj\u00f6rn Lind, Arne Lindberger, P. Petersson and Madeline Wallmark."}},
{"article_title": "Intracytoplasmic sperm injection", "pageid": "153187", "revid": "1059959642", "timestamp": "2021-12-12T17:52:41Z", "history_paths": [["Intracytoplasmic sperm injection --- Introduction ---", "History"]], "categories": ["assisted reproductive technology", "fertility medicine", "1991 introductions"], "heading_tree": {"Intracytoplasmic sperm injection --- Introduction ---": {"Round spermatid injection (ROSI)": {}, "Indications": {}, "Sperm selection": {}, "History": {}, "Procedure": {}, "Assisted zona hatching (AH)": {"Preimplantation genetic diagnosis (PGD)": {}}, "Success or failure factors": {}, "Complications": {}, "Follow-up on fetus": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Intracytoplasmic sperm injection --- Introduction ---|History": "The first child born from a gamete micromanipulation (technique in which special tools and inverted microscopes are used that help embryologists to choose and pick an individual sperm for [http://www.testtubebabyprocess.com/2016/12/icsi-ivf.html ICSI IVF]) was a Singapore-born child in April 1989.<ref>{{cite book|title=Third Party Assisted Conception Across Cultures: Social, Legal and Ethical Perspectives|authors=Blyth, Eric; Landau, Ruth|publisher=Jessica Kingsley Publishers|year= 2004|isbn=9781843100843|url=https://books.google.com/books?id=KtMPBQAAQBAJ&q=SUZI+ng+%22april+1989%22&pg=PA193}}</ref>\n\nThe technique was developed by [[Gianpiero D. Palermo|Gianpiero Palermo]] at the [[Vrije Universiteit Brussel]], in the Center for Reproductive Medicine headed by [[Paul Devroey]] and [[Andre Van Steirteghem]].<ref>{{Cite journal|last1=Palermo|first1=G.|last2=Joris|first2=H.|last3=Devroey|first3=P.|last4=Van Steirteghem|first4=A. C.|date=1992-07-04|title=Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte|journal=Lancet|volume=340|issue=8810|pages=17\u201318|issn=0140-6736|pmid=1351601|doi=10.1016/0140-6736(92)92425-F|s2cid=2916063}}</ref> \nActually, the discovery was made by a mistake.\n\nThe procedure itself was first performed in 1987,<ref>{{cite journal | url=http://www.fertstert.org/article/S0015-0282(16)59893-8/pdf | title=A preclinical evaluation of pronuclear formation by microinjection of human spermatozoa into human oocytes | vauthors=Lanzendorf SE, Maloney MK, Veeck LL, Slusser J, Hodgen GD, Rosenwaks Z | journal=Fertility and Sterility | year=1988 | volume=49 | issue=5 | pages=835\u201342 | doi=10.1016/S0015-0282(16)59893-8 | pmid=3360172}}</ref> though it only went to the pronuclear stage.<ref>{{cite journal | title=Laser-assisted ICSI: a novel approach to obtain higher oocyte survival and embryo quality rates | author=S.Abdelmassih | author2= J. Cardoso1 | author3=V. Abdelmassih | author4=J. A. Dias | author5=R. Abdelmassih | author6= Z. P. Nagy | journal=Human Reproduction | year=2002 | volume=17 | issue=10 | pages=2694\u20132699 | doi=10.1093/humrep/17.10.2694| pmid=12351550 | doi-access=free }}</ref> The first activated embryo by ICSI was produced in 1990,<ref>{{cite book|url=https://books.google.com/books?id=kJ8nCGCJ2WQC&q=icsi+palermo+%22october+1990%22&pg=PA16|title=Baby-Making: What the New Reproductive Treatments Mean for Families and Society|first1=Bart|last1=Fauser|first2=Paul|last2=Devroey|date=27 October 2011|publisher=OUP |via=Google Books|isbn=9780199597314}}</ref> but the first successful birth by ICSI took place on January 14, 1992 after an April 1991<ref>{{cite journal|title=Celebrating ICSI's twentieth anniversary and the birth of more than 2.5 million children\u2014the 'how, why, when and where'|first=Andr\u00e9|last=Van Steirteghem|date=1 January 2012|journal=Human Reproduction|volume=27|issue=1|pages=1\u20132|doi=10.1093/humrep/der447|pmid=22180598|doi-access=free}}</ref> conception.<ref>{{cite book|editor1=Eric R. M. Jauniaux |editor2=Botros R. M. B. Rizk|title= Pregnancy After Assisted Reproductive Technology|isbn=9781107006478|contribution=Introduction|url=http://assets.cambridge.org/97811070/06478/excerpt/9781107006478_excerpt.pdf|publisher=Cambridge University Press|date= 2012-09-06}}</ref>\n\nSharpe ''et al'' comment on the success of ICSI since 1992 saying, "[t]hus, the woman carries the treatment burden for male infertility, a fairly unique scenario in medical practice. ICSI\u2019s success has effectively diverted attention from identifying what causes male infertility and focused research onto the female, to optimize the provision of eggs and a receptive endometrium, on which ICSI\u2019s success depends."<ref>{{cite journal | last1 = Barratt | first1 = Christopher L.R. | last2 = De Jonge | first2 = Christopher J. | last3 = Sharpe | first3 = Richard M. | title = 'Man Up': the importance and strategy for placing male reproductive health centre stage in the political and research agenda | journal = [[Human Reproduction (journal)|Human Reproduction]] | volume = 33 | issue = 4 | pages = 541\u2013545 | doi = 10.1093/humrep/dey020 | pmid = 29425298 | pmc = 5989613 | date = 7 February 2018 }}</ref><ref>{{cite news | last = Knapton | first = Sarah | title = IVF to fix male infertility 'infringes human rights of women' argue scientists | url = https://www.telegraph.co.uk/science/2018/03/06/ivf-fix-male-infertility-infringes-human-rights-women-argue/ | work = [[The Daily Telegraph|The Telegraph]] | date = 6 March 2018 | access-date = 7 March 2018}}</ref>"}},
{"article_title": "I = PAT", "pageid": "153767", "revid": "1057412703", "timestamp": "2021-11-27T13:55:18Z", "history_paths": [["I = PAT --- Introduction ---", "History"]], "categories": ["human impact on the environment", "environmental social science concepts", "equations", "human geography", "technology assessment", "population ecology"], "heading_tree": {"I = PAT --- Introduction ---": {"History": {}, "The dependent variable: Impact": {}, "The three factors": {"Population": {"Environmental impacts of population": {}}, "Affluence": {"Environmental impacts of affluence": {}}, "Technology": {"Environmental impacts of technology": {}}}, "Criticism": {"Interdependencies": {}, "Neglect of beneficial human impacts": {}, "Neglect of political and social contexts": {}, "Policy implications": {}}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"I = PAT --- Introduction ---|History": "The equation was developed in 1970 during the course of a debate between [[Barry Commoner]], [[Paul R. Ehrlich]] and [[John Holdren]]. Commoner argued that [[environmental impact]]s in the United States were caused primarily by changes in its production technology following [[World War II]] and focused on present-day deteriorating environmental conditions in the United States. Ehrlich and Holdren argued that all three factors were important but emphasized the role of human [[population growth]], focusing on a broader scale, being less specific in space and time.<ref name ="End of Population Growth">{{cite book | last1 = O'Neill | first1 = B.C. |last2 = MacKellar | first2 = F.L. | first3 = W.| last3= Lutz | date = 2004 | chapter = Population, greenhouse gas emissions, and climate change | title = The End of World Population Growth in the 21st Century: New Challenges for Human Capital Formation & Sustainable Development | editor1-first = W. | editor1-last = Lutz | editor2-first = W.C. | editor2-last= Sanderson | editor3-first= S. | editor3-last = Scherbov | publisher = Earthscan Press | location = London | pages = 283\u2013314}}</ref><ref>{{Cite journal | last1 = Ehrlich  | first1 = Paul R.  | author-link1 = Paul R. Ehrlich | last2 =Holdren  | first2 =  John P. | author-link2 = John Holdren | year = 1971 | title = Impact of Population Growth | journal = [[Science (journal)|Science]] | volume = 171 | issue = 3977 | pages = 1212\u20131217 | publisher = [[American Association for the Advancement of Science]] | jstor = 1731166 | doi=10.1126/science.171.3977.1212| pmid = 5545198 | bibcode = 1971Sci...171.1212E }}</ref><ref>{{Cite journal|last=Chertow|first=Marian|year=2001|title=The IPAT Equation and Its Variants|journal=Changing Views of Technology and Environmental Impact}}</ref><ref name=BAS1>{{cite journal |journal=[[Bulletin of the Atomic Scientists]] |author= Barry Commoner | author-link = Barry Commoner |date=May 1972 |title=A Bulletin Dialogue: on "The Closing Circle" - Response |url=https://books.google.com/books?id=pwsAAAAAMBAJ&pg=PA17 |volume=28 |issue=5 |pages=17, 42\u201356 |doi=10.1080/00963402.1972.11457931 }} \u2014\u2014 {{Cite journal |url=https://books.google.com/books?id=pwsAAAAAMBAJ&pg=PA16 |date=May 1972 |title=A Bulletin Dialogue: on "The Closing Circle" - Critique |journal=Bulletin of the Atomic Scientists |last1=Ehrlich |first1=P.R. |last2=Holdren |first2=J.P |volume=28 |issue=5 |pages=16, 18\u201327|doi=10.1080/00963402.1972.11457930 }}</ref>\n\nThe equation can aid in understanding some of the factors affecting human impacts on the environment,<ref>{{Cite journal | last1 = Chertow | first1 = M. R. | author-link1 = Marian Chertow| title = The IPAT Equation and Its Variants | doi = 10.1162/10881980052541927 | journal = Journal of Industrial Ecology | volume = 4 | issue = 4 | pages = 13\u201329 | year = 2000 }}</ref> but it has also been cited as a basis for many of the dire environmental predictions of the 1970s by [[Paul R. Ehrlich|Paul Ehrlich]], [[George Wald]], [[Denis Hayes]], [[Lester R. Brown|Lester Brown]], [[Ren\u00e9 Dubos]], and [[Sidney Dillon Ripley|Sidney Ripley]] that did not come to pass.<ref name="bailey_2000">[[Ronald Bailey|R Bailey]] (2000) ''Earth day then and now'', [[Reason (magazine)|Reason]] '''32'''(1), 18-28</ref> [[Neal Koblitz]] classified equations of this type as "mathematical [[propaganda]]" and criticized Ehrlich's use of them in the media (e.g. on ''[[The Tonight Show]]'') to sway the general public.<ref name="koblitz_1981">[[Neal Koblitz|N Koblitz]] (1981) "Mathematics as Propaganda", in ''Mathematics Tomorrow'', ed. [[Lynn Steen]], pp 111-120.</ref>"}},
{"article_title": "Cassette deck", "pageid": "153914", "revid": "1060653002", "timestamp": "2021-12-16T21:05:45Z", "history_paths": [["Cassette deck --- Introduction ---", "History"]], "categories": ["audio players", "recording devices", "tape recording", "1963 in technology", "audiovisual introductions in 1963", "products introduced in 1963"], "heading_tree": {"Cassette deck --- Introduction ---": {"History": {"Origins": {}, "Widespread use": {}, "Performance improvements and additional features": {}}, "Noise reduction and fidelity": {}, "In-car entertainment systems": {}, "Maintenance": {}, "Decline in popularity": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cassette deck --- Introduction ---|History": "[[Image:TeacTopCassetteDeck.jpg|thumb|right|Typical [[Teac]] top loading stereo cassette deck from mid-1970s]]\n[[Image:RadioShack-ctr-119.jpg|thumb|right|A typical portable desktop cassette recorder from [[RadioShack]].]]\nThe first consumer tape recorder to employ a tape reel permanently housed in a small removable cartridge was the [[RCA tape cartridge]], which appeared in 1958 as a predecessor to the cassette format. At that time, [[reel to reel]] recorders and players were commonly used by enthusiasts, but required large individual reels and tapes which had to be threaded by hand, making them less-accessible to the casual consumer. Both [[RCA]] and Bell Sound attempted to commercialize the cartridge format, but a few factors stalled adoption, including lower-than-advertised availability of selections in the prerecorded media catalog, delays in production setup, and a stand-alone design that was not considered by audiophiles to be truly hi-fi.<ref name="rca cartridge">{{cite web |url=http://blog.dianaschnuth.com/details/audio/cartridge.html |title=RCA Cartridges: 1958 - 1964 |last1=Cook |first1=Diana |last2=Morton |first2=David |publisher=Diana Cook |website=A History of Magnetic Audio Tape |access-date=25 October 2016}}</ref>\n\nThe "compact cassette" (a Philips trademark)<ref name=BILLREP1 /> was introduced by the [[Philips]] Corporation at the [[Internationale Funkausstellung Berlin]] in 1963<ref>[http://www.harsmedia.com/SoundBlog/Archief/00793.php Mourning and Celebrating 50 years of Compact Cassette] {{Webarchive|url=https://web.archive.org/web/20131009015801/http://www.harsmedia.com/SoundBlog/Archief/00793.php |date=2013-10-09 }} - SoundBlog, 23 March 2013. Retrieved 25 August 2013.</ref><ref>"Rewound. On its 50th birthday, the cassette tape is still rolling". ''[[Time (magazine)|Time]]''. 12 August 2013. p. 56-57.</ref> and marketed as a device purely intended for portable speech-only [[dictation machine]]s.{{citation needed|date=April 2013}} The tape width was <sup>1</sup>\u2044<sub>8</sub> inch (actually 0.15 inch, 3.81 mm) and tape speed was 1.875 inches (4.8 cm) per second, giving a decidedly non Hi-Fi frequency response and quite high noise levels.<ref name="cassettes 1963">{{cite web\n | url =http://blog.dianaschnuth.com/details/audio/cassette.html\n | title =Cassettes: 1963 - present\n | last1 =Hinman\n | first1 =Doug\n | last2 =Brabazon\n | first2 =Brabazon\n | date =1994\n | website =A History of Magnetic Audio Tape\n | publisher =Diana Cook\n | access-date =25 October 2016\n | quote =Cassettes were originally disdained by audio critics as very low-end technology ... a very low perceived potential for sound reproduction}}</ref>\n\nEarly recorders were  intended for dictation and journalists, and were typically hand-held battery-powered devices with built-in microphones and [[automatic gain control]] on recording. Tape recorder audio-quality had improved by the mid-1970s, and a cassette deck with manual level controls and [[VU meter]]s became a standard component of home high-fidelity systems.<ref name=BILLREP1 /> Eventually the reel-to-reel recorder was completely displaced, in part because of the usage constraints presented by their large size, expense, and the inconvenience of threading and rewinding the tape reels - cassettes are more portable and can be stopped and immediately removed in the middle of playback without rewinding. Cassettes became extremely popular for automotive and other  portable music applications.  Although pre-recorded cassettes were widely available, many users would combine ([[Dubbing (music)|dub]]) songs from their [[vinyl record]]s or cassettes to make a new custom [[mixtape]] cassette.\n\nIn 1970, the [[Advent Corporation]] combined [[Dolby Noise Reduction|Dolby B]] noise reduction system with [[chromium dioxide]] (CrO<sub>2</sub>) tape to create the [[Advent Model 200]], the first high-fidelity cassette deck.<ref>[http://www.davidreaton.com/Cassette_Decks.htm Advent cassette decks] {{webarchive |url=https://web.archive.org/web/20090625174438/http://www.davidreaton.com/Cassette_Decks.htm |date=June 25, 2009 }}</ref> Dolby B uses volume [[companding]] of high frequencies to boost low-level treble information by up to 9 dB, reducing them (and the hiss) on playback.  CrO<sub>2</sub> used different bias and equalization settings to reduce the overall noise level and extend the high frequency response. Together these allowed a usefully flat frequency response beyond 15 kHz for the first time. This deck was based on a top-loading mechanism by Nakamichi, then soon replaced by the Model 201 based on a more reliable transport made by [[Wollensak]], a division of [[3M]], which was commonly used in audio/visual applications. Both featured an unusual single VU meter which could be switched between or for both channels. The Model 200 featured [[piano key]] style transport controls, with the Model 201 using the distinctive combination of a separate lever for rewind/fast forward and the large play and stop button as found on their commercial reel to reel machines of the era.\n\nMost manufacturers adopted a standard top-loading format with [[piano key]] controls, dual VU meters, and slider level controls. There was a variety of configurations leading to the next standard format in the late 1970s, which settled on front-loading (see main picture) with cassette well on one side, dual VU meters on the other, and later dual-cassette decks with meters in the middle. Mechanical controls were replaced with electronic push buttons controlling [[solenoid]] mechanical actuators, though low cost models would retain mechanical controls. Some models could search and count gaps between songs.\n\n Cassette decks soon came into widespread use and were designed variously for professional applications, home audio systems, and for mobile use in cars, as well as portable recorders. From the mid-1970s to the late 1990s the cassette deck was the preferred music source for the automobile. Like an [[8-track cartridge]], it was relatively insensitive to vehicle motion, but it had reduced tape [[Flutter (electronics and communication)|flutter]], as well as the obvious advantages of smaller physical size and fast forward/rewind capability.\nA major boost to the cassette's popularity came with the release of the [[Sony Walkman]] "personal" cassette player in 1979, designed specifically as a headphone-only ultra-compact "wearable" music source. Although the vast majority of such players eventually sold were not Sony products, the name "Walkman" has become synonymous with this type of device.\n\nCassette decks were eventually manufactured by almost every well known brand in home audio, and many in professional audio, with each company offering models of very high quality.\n\n [[File:Revox B215 cassette deck (crop).jpg|thumb|Revox B 215, 4-motor-cassette deck without belts (direct drive, 1985\u20131992)]]\n[[File:Nakamichi-130310-0002EC.jpg|thumb|[[Nakamichi Dragon]] cassette deck with azimuth adjustment 1983 - 1993, 1995 (Last Edition)]]\nCassette decks reached their pinnacle of performance and complexity by the mid-1980s. {{Citation needed|date=December 2017}} Cassette decks from companies such as [[Nakamichi]], [[Revox]], and [[Tandberg]] incorporated advanced features such as multiple [[tape head]]s and dual [[capstan (tape recorder)|capstan]] drive with separate reel motors. Auto-reversing decks became popular and were standard on most factory installed automobile decks. \n\nAs a part of the [[Digital Revolution]], the ongoing development of electronics technology [[Moore's Law|decreased the cost of digital circuitry]] to the point that the technology could be applied to consumer electronics. The application of such [[digital electronics]] to cassette decks provides an early example of [[Mechatronics|mechatronic]] design, which aims to enhance mechanical systems with electronic components in order to improve performance, increase system flexibility, or reduce cost.<ref>{{cite book |last=van Amerongen |first=Job |editor-last=Bishop |editor-first=Robert H. |title=Mechatronics: An Introduction |publisher=CRC Press |date=2005 |page=12.1 |chapter=Chapter 12: The Role of Controls in Mechatronics |isbn=978-1-4200-3724-1|url=https://books.google.com/books?id=CTfQPQRooMgC}}</ref> The inclusion of [[Logic gate|logic circuitry]] and [[Solenoid|solenoids]] into the transport and control mechanisms of cassette decks, often referred to "logic control", contrasts with earlier "piano-key" transport controls and mechanical linkages. One goal of using logic circuitry in cassette decks or recorders was to [[Error-tolerant design|minimize equipment damage upon incorrect user input]] by including [[Fail-safe|fail-safes]] into the transport and control mechanism.<ref>{{cite patent | country = United States | number = 3347996 A | title = Control system for a magnetic recorder | pubdate = 1967-10-17 | fdate = 1963-10-25 | pridate = 1962-10-27 | inventor = Goji Uchikoshi | url = https://www.google.com/patents/US3347996}} "By the provision of a logical circuit in the control circuit for a magnetic recorder, even when the keys of the key board are actuated in any desired sequence, the magnetic recorder and its associated devices can be promptly and precisely controlled without causing any damages thereon."</ref> Such fail-safe behavior was described in a review by [[Julian Hirsch]] of a particular cassette deck featuring logic control.<ref>{{cite magazine |last1= Hirsch |first1= Julian|author-link1=Julian Hirsch |date= May 1979 |title=Eumig 'CCD' Cassette Deck |url=http://www.americanradiohistory.com/Archive-Poptronics/70s/1979/Poptronics-1979-05.pdf  |magazine=[[Popular Electronics]] |access-date=18 December 2017 |quote=The transport controls are fully logic operated through solenoids. Any transport control button can be touched while the machine is running in any mode without risking damage to tape or deck. Even the button for the cassette compartment door can be operated while the tape is running. |pages=39\u201344}}</ref> Some examples of fail-safe mechanisms incorporated into logic control decks include: a mechanism designed to protect internal components from damage when the tape or motor is locked, a mechanism designed to prevent the tape from being wound improperly, among others.<ref>{{cite journal |last1= Takahata |first1= Masato |last2= Michinaka |first2= Takashi |last3= Goto |first3= Tsutomu |last4= Igawa |first4= Yoshihisa |last5= Arai |first5= Kenboku |last6= Takata |first6= Masanao |display-authors=1|date= 1991|title= Logic Controlled Cassette Deck Mechanism "DK-76" |url= https://www.denso-ten.com/business/technicaljournal/pdf/4-5E.pdf|journal= Fujitsu Ten Technical Journal |issue= 4|pages= 52\u201360|access-date= 2017-12-12}}</ref> Some logic control decks were designed to incorporate light-touch buttons or [[remote control]], among other features marketed as being convenient.<ref>{{cite magazine |last1= Hirsch |first1=Julian |author-link1=Julian Hirsch |date= May 1979 |title=Aiwa Model AD-6900 cassette deck |url=http://www.americanradiohistory.com/Archive-Poptronics/70s/1979/Poptronics-1979-09.pdf  |magazine=[[Popular Electronics]] |access-date=18 Dec 2017 |quote=There was a slight "clunk" from the solenoids as they operated, but the buttons themselves required almost no activating pressure, and the control logic appeared to be as foolproof as claimed. |pages=28\u201331}}</ref><ref>{{cite web |url=http://www.ant-audio.co.uk/Tape_Recording/JVC/JVC_Cassette_Decks__1982_LR.pdf |title= JVC Stereo Cassette Decks |date=1982 |publisher=Victor Company of Japan |access-date= 2017-12-13|quote= "The following conveniences are available: *Direct change of mode... *Light-touch button... *Punch-in recording... *Remote control..."}}</ref> In the [[Vehicle audio|car stereo]] industry, full logic control was developed with the aim of [[miniaturization]], so that the cassette deck would take up less dashboard space.<ref>{{cite journal |last1= Takai |first1= Kazuki |date= 1985-02-01|title= Ultra-Compact, Full-Logic Cassette Mechanism|url= http://papers.sae.org/850024/|journal= SAE Technical Paper 850024|series= SAE Technical Paper Series |volume= 1 |pages= 20|doi= 10.4271/850024|access-date= 2017-12-13}}</ref>\n\nThree-head technology uses separate heads for recording and playback (the third of the three heads being the erase head). \nThis allows different record and playback head gaps to be used. \nA narrower head gap is optimal for playback than for recording, so the head gap width of any combined record/playback head must necessarily be a compromise.  \nSeparate record and playback heads also allow off-the-tape monitoring during recording, permitting immediate verification of the recording quality. \n(Such machines can be identified by the presence of a "monitor" switch with positions for "tape" and "source", or similar.) \nThree-head systems were common on reel-to-reel decks, but were more difficult to implement for cassettes, \nwhich do not provide separate openings for record and play heads. \nSome models squeezed a monitor head into the capstan area, and others combined separate record and playback gaps into a single headshell.\n[[File:Harman Kardon TD4800-130311-0014EC (cropped).jpg|thumb|Dolby S cassette deck by harman/kardon (1990)]]<ref>[https://fonoforum.de/archiv?tx_archive_pi1%5Baction%5D=download&tx_archive_pi1%5Barticle%5D=17754&tx_archive_pi1%5Bcontroller%5D=Archive&cHash=9aa9b2bbd41d9f64be1ff21632d57fd8 fonoforum.de 8/1991, Testreport Dolby-S-Kassettendeck] {{Webarchive|url=https://web.archive.org/web/20200412073132/https://fonoforum.de/archiv?tx_archive_pi1%5Baction%5D=download&tx_archive_pi1%5Barticle%5D=17754&tx_archive_pi1%5Bcontroller%5D=Archive&cHash=9aa9b2bbd41d9f64be1ff21632d57fd8 |date=2020-04-12 }} (German; PDF, 2 MB)</ref>\nThe [[Dolby noise reduction system|Dolby B noise reduction system]] was key to realizing low noise performance on slow, narrow, cassette tapes. It works by boosting the high frequencies on recording, especially low-level high-frequency sounds, with corresponding high frequency reduction on playback. This lowers the high frequency noise (hiss) by approximately 9 dB. Enhanced versions included [[Dolby C]] (in 1980) and [[Dolby S]] types. Of the three, however, only Dolby B became common on automobile decks.\n\n[[Bang & Olufsen]] developed the [[HX Pro]] headroom extension system in conjunction with [[Dolby Laboratories]] in 1982. This was used in many higher-end decks. HX Pro reduces the high-frequency bias during recording when the signal being recorded has a high level of high frequency content. Such a signal is self-biasing. Reducing the level of the bias signal permits the desired signal to be recorded at a higher level without saturating the tape, thus increasing "headroom" or maximum recording level.\n\nSome decks incorporated microprocessor programs to adjust tape bias and record level calibration automatically.\n\nIn later years, an "auto reverse" feature appeared that allowed the deck to play (and, in some decks, record) on both sides of the cassette without the operator having to manually remove, flip, and re-insert the cassette. \nMost auto-reverse machines use a four channel head (similar to those on multitrack recorders), with only two channels connected to the electronics at one time, one pair for each direction. \nAuto-reverse decks employ a capstan and pinch roller for each side. \nSince these use the same opening in the cassette shell normally used for the erase head, \nsuch decks must fit the erase head (or two, one for each direction) into the center opening in the shell along with the record/play head.\n\nIn later auto reverse machines, the "auto reverse" mechanism uses an ordinary two-track, quarter-width head, \nbut operates by mechanically rotating the head 180 degrees so that the two head gaps access the other tracks of the tape. \nThere is usually an azimuth adjustment screw for each position. \nNevertheless, due to the repeated movement, the alignment (in particular, the azimuth) deviates with usage. \nEven in a machine with a four channel head, slight asymmetries in the cassette shell make it difficult to align the \nhead perfectly for both directions. {{Citation needed|date=March 2012}} \n\n[[File:Nakamichi RX 505 Front edited.jpg|thumb|Nakamichi RX series RX-505 deck]]\n[[File:Nakamichi RX 505 Top Open1.jpg|thumb|RX-505 auto reverse mechanism]]\n\nIn one machine, the "Dragon", Nakamichi addressed the issue with a motor-driven automatic head alignment mechanism. \nThis proved effective but very expensive. \nLater Nakamichi auto-reverse models, the RX series, was essentially a single-directional deck, \nbut with an added mechanism that physically removed the cassette from the transport, flipped it over, and re-inserted it. \nAkai made a similar machine but with the mechanism and cassette laid out horizontally instead of upright.\nThis permitted the convenience of auto-reverse with little compromise in record or playback quality.{{Citation needed|date=March 2012}}\n\nNew tape formulations were introduced. \n[[Chromium dioxide]] (referred to as CrO<sub>2</sub> or Type II) was the first tape designed for extended high frequency response, but it required higher bias. Later, as the IEC Type II standard was defined, a different equalization settings was also mandated to reduce hiss, thus giving up some extension at the high end of the audio spectrum. \nBetter-quality cassette recorders soon appeared with a switch for the tape type. \nLater decks incorporated coded holes in the shell to autodetect the tape type. \nChromium dioxide tape was thought to cause increased wear on the heads, so TDK and Maxell adapted cobalt-doped ferric formulations to mimic CrO<sub>2</sub>. \nSony briefly tried FerriChrome (Type III) which claimed to combine the best of both; some people, however, stated that the reverse was true because the Cr top layer seemed to wear off quickly, reducing this type to Fe in practice. Most recent decks produce the best response and dynamic headroom with metal tapes (IEC Type IV) which require still higher bias for recording, though they will play back correctly at the II setting since the equalization is the same.\n\nWith all of these improvements, the best units could record and play the full audible spectrum from 20 Hz to over 20 kHz (although this was commonly quoted at -10, -20 or even -30 dB, not at full output level), with [[wow (recording)|wow and flutter]] less than 0.05% and very low noise. A high-quality recording on  cassette could rival the sound of an average commercial CD, though the quality of pre-recorded cassettes has been regarded by the general public as lower than could be achieved in a quality home recording.<ref name=FORUM1>{{cite news|title=Prerecorded cassette quality?|website=AudioKarma.org|type=Forum|date=2005-09-05}}</ref> There was a call for better sound quality in 1981, surprisingly by the head of [[Tower Records]], Russ Solomon. At a meeting of the [[National Association of Recording Merchandisers]] (NARM) Retail Advisory Committee in [[Carlsbad, California]], Solomon played two recordings of a [[Santana (band)|Santana]] track; one he had recorded himself and the pre-recorded cassette release from [[Columbia Records]]. He used this technique to demonstrate what he called "the tunnel effect" in the audio range of pre-recorded cassettes and commented to the reporter Sam Sutherland, who wrote a news article printed in ''Billboard'' magazine:\n\n<blockquote>\n"The buyer who is aware of sound quality is making his own." "They won't be satisfied with the 'tunnel effect' of prerecorded tape. And home tape deck users don't use prerecorded tapes at all." Yet, contended Solomon, while Tower's own stores show strong blank tape sales gains, it's prerecorded sales have increased by only 2% to 3%. With an estimated 15% of the chain's total tape business now generated by the sales of blanks, "it would appear our added tape sales are going to TDK, Maxell and Sony, not you." he concluded. - ''[[Billboard (magazine)|Billboard]]'', Vol. 93, No. 38, 26 September 1981.<ref name=BILLBOARDSS1>{{cite journal|journal=[[Billboard (magazine)|Billboard]]|title=Better Cassette Quality Urged|date=26 Sep 1981|volume=93|issue=38|pages=3, 6|url=https://books.google.com/books?id=vSQEAAAAMBAJ&q=pre+recorded+cassette+quality+v+home+recording&pg=PT5|access-date=4 June 2013|first=Sam |last= Sutherland}}</ref>\n</blockquote>"}},
{"article_title": "Exhaust gas recirculation", "pageid": "158740", "revid": "1062742831", "timestamp": "2021-12-30T07:26:42Z", "history_paths": [["Exhaust gas recirculation --- Introduction ---", "History"]], "categories": ["engine technology", "chemical process engineering", "air pollution control systems", "nox control"], "heading_tree": {"Exhaust gas recirculation --- Introduction ---": {"History": {}, "EGR": {}, "In diesel engines": {}, "See also": {}, "Sources": {"References": {}}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Exhaust gas recirculation --- Introduction ---|History": "The first EGR systems were crude; some were as simple as an [[Calibrated orifice|orifice jet]] between the exhaust and intake tracts which admitted exhaust to the intake tract whenever the engine was running. Difficult starting, rough idling, and reduced performance and fuel economy resulted.<ref name=Petersen>{{cite book | last = Rosen (Ed.) | first = Erwin M. | title = The Peterson automotive troubleshooting & repair manual | publisher = Grosset & Dunlap, Inc. | year = 1975 | isbn = 978-0-448-11946-5 }}</ref> By 1973, an EGR valve controlled by [[manifold vacuum]] opened or closed to admit exhaust to the intake tract only under certain conditions. Control systems grew more sophisticated as automakers gained experience; Volkswagen's "Coolant Controlled Exhaust Gas Recirculation" system of 1973 exemplified this evolution: a coolant temperature sensor blocked vacuum to the EGR valve until the engine reached normal [[operating temperature]].<ref name=Petersen/> This prevented driveability problems due to unnecessary exhaust induction; {{NOx}} forms under elevated temperature conditions generally not present with a cold engine. Moreover, the EGR valve was controlled, in part, by vacuum drawn from the [[Carburetor|carburetor's]] venturi, which allowed more precise constraint of EGR flow to only those engine load conditions under which {{NOx}} is likely to form.<ref name=MTSC_73-1>[http://www.imperialclub.com/Repair/Lit/Master/302/page07.htm "1973 Cleaner Air System Highlights" \u2013 Chrysler Corporation], imperialclub.com</ref> Later, [[backpressure]] [[transducer]]s were added to the EGR valve control to further tailor EGR flow to engine load conditions. Most modern engines now need exhaust gas recirculation to meet emissions standards. However, recent innovations have led to the development of engines that do not require them. The 3.6 [[Chrysler Pentastar engine]] is one example that does not require EGR.<ref>{{Cite web |url=http://www.autoguide.com/auto-news/2010/10/2011-dodge-challenger-officially-revealed-with-305-hp-pentastar-v6.html |title=2011 Dodge Challenger Officially Revealed With 305-HP Pentastar V6 |work=autoguide.com |access-date=26 September 2011 }}</ref>"}},
{"article_title": "Computer-aided manufacturing", "pageid": "162289", "revid": "1044157199", "timestamp": "2021-09-13T21:20:15Z", "history_paths": [["Computer-aided manufacturing --- Introduction ---", "History"]], "categories": ["computer-aided manufacturing", "information technology management", "product lifecycle management"], "heading_tree": {"Computer-aided manufacturing --- Introduction ---": {"Overview": {}, "History": {"Overcoming historical shortcomings": {}}, "Machining process": {}, "Software: large vendors": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Computer-aided manufacturing --- Introduction ---|History": "Early commercial applications of CAM were in large companies in the automotive and aerospace industries; for example, [[Pierre B\u00e9zier]]s work developing the CAD/CAM application [[UNISURF]] in the 1960s for car body design and tooling at [[Renault]].<ref>{{cite web|last=Dokken|first=Tor|title=The History of CAD|url=http://www.saga-network.eu/index.php/resources/downloads/category/2-kolimpari?download=42%3Ator-dokken-the-history-of-cad-and-examples-of-its-use-in-industry|publisher=The SAGA-project|access-date=17 May 2012|archive-url=https://web.archive.org/web/20121102082519/http://www.saga-network.eu/index.php/resources/downloads/category/2-kolimpari?download=42%3Ator-dokken-the-history-of-cad-and-examples-of-its-use-in-industry|archive-date=2 November 2012|url-status=dead}}</ref> Alexander Hammer at DeLaval Steam Turbine Company invented a technique to progressively drill turbine blades out of a solid metal block of metal with the drill controlled by a punch card reader in 1950.\n\nHistorically, CAM software was seen to have several shortcomings that necessitated an overly high level of involvement by skilled [[CNC]] machinists. Fallows created the first CAD software but this had severe shortcomings and was promptly taken back into the developing stage.{{Citation needed|date=March 2010}} CAM software would output code for the least capable machine, as each machine tool control added on to the standard [[G-code]] set for increased flexibility.  In some cases, such as improperly set up CAM software or specific tools, the CNC machine required manual editing before the program will run properly.  None of these issues were so insurmountable that a thoughtful engineer or skilled machine operator could not overcome for prototyping or small production runs; G-Code is a simple language.  In high production or high precision shops, a different set of problems were encountered where an experienced CNC machinist must both hand-code programs and run CAM software.\n\nThe integration of CAD with other components of CAD/CAM/CAE [[Product lifecycle management]] (PLM) environment requires an effective [[CAD data exchange]]. Usually it had been necessary to force the CAD operator to export the data in one of the common data formats, such as [[IGES]] or [[STL (file format)|STL]] or [[Parasolid]] formats that are supported by a wide variety of software.\nThe output from the CAM software is usually a simple text file of G-code/M-codes, sometimes many thousands of commands long, that is then transferred to a machine tool using a [[direct numerical control]] (DNC) program or in modern Controllers using a common [[USB]] Storage Device.\n\nCAM packages could not, and still cannot, reason as a machinist can. They could not optimize toolpaths to the extent required of [[mass production]]. Users would select the type of tool, machining process and paths to be used. While an engineer may have a working knowledge of G-code programming, small optimization and wear issues compound over time.  Mass-produced items that require machining are often initially created through casting or some other non-machine method.  This enables hand-written, short, and highly optimized G-code that could not be produced in a CAM package.\n\nAt least in the United States, there is a shortage of young, skilled machinists entering the workforce able to perform at the extremes of manufacturing; high precision and mass production.<ref>Joshua Wright. Forbes. March 7, 2013. https://www.forbes.com/sites/emsi/2013/03/07/americas-skilled-trades-dilemma-shortages-loom-as-most-in-demand-group-of-workers-ages/</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB10001424127887323744604578470890996410044|title=Help Wanted. A Lot of It.|last=Hagerty|first=James R.|date=2013-06-10|work=Wall Street Journal|access-date=2018-06-02|language=en-US|issn=0099-9660}}</ref>  As CAM software and machines become more complicated, the skills required of a machinist or machine operator advance to approach that of a computer programmer and engineer rather than eliminating the CNC machinist from the workforce.\n\n;Typical areas of concern\n* High-Speed Machining, including streamlining of tool paths\n* Multi-function Machining\n* 5 Axis Machining\n* [[Feature recognition]] and machining\n* Automation of Machining processes\n* Ease of Use\n\n Over time, the historical shortcomings of CAM are being attenuated, both by providers of niche solutions and by providers of high-end solutions. This is occurring primarily in three arenas:\n# Ease of usage\n# Manufacturing complexity\n# Integration with [[Product life-cycle management (marketing)|PLM]] and the extended enterprise<ref>{{Cite book|url=https://books.google.com/books?id=fJsvJgppWWoC&q=Over+time%2C+the+historical+shortcomings+of+CAM+are+being+attenuated%2C+both+by+providers+of+niche+solutions+and+by+providers+of+high-end+solutions.+This+is+occurring+primarily+in+three+arenas%3A+Ease+of+usage+Manufacturing+complexity+Integration+with+PLM+and+the+extended+enterprise&pg=PA313|title=Basic Civil Engineering|last=Gopi|date=2010-01-01|publisher=Pearson Education India|isbn=9788131729885|language=en}}</ref>\n\n;Ease in use\n\n:For the user who is just getting started as a CAM user, out-of-the-box capabilities providing Process Wizards, templates, libraries, machine tool kits, automated feature based machining and job function specific tailorable user interfaces build user confidence and speed the learning curve.\n:User confidence is further built on 3D visualization through a closer integration with the 3D CAD environment, including error-avoiding simulations and optimizations.\n\n;Manufacturing complexity\n:The manufacturing environment is increasingly complex. The need for CAM and PLM tools by the manufacturing engineer, NC programmer or machinist is similar to the need for computer assistance by the pilot of modern aircraft systems. The modern machinery cannot be properly used without this assistance.\n:Today's CAM systems support the full range of machine tools including: [[turning]], [[Multiaxis machining|5 axis machining]], [[Water jet cutter|waterjet]], [[Laser cutting|laser]] / [[plasma cutting]], and [[Wire cutting|wire EDM]]. Today\u2019s CAM user can easily generate streamlined tool paths, optimized tool axis tilt for higher feed rates, better tool life and surface finish, and ideal cutting depth. In addition to programming cutting operations, modern CAM softwares can additionally drive non-cutting operations such as [[Coordinate-measuring machine#New probing systems|machine tool probing]].\n\n;Integration with PLM and the extended enterpriseLM to integrate manufacturing with enterprise operations from concept through field support of the finished product.\n:To ensure ease of use appropriate to user objectives, modern CAM solutions are scalable from a stand-alone CAM system to a fully integrated multi-CAD 3D solution-set.  These solutions are created to meet the full needs of manufacturing personnel including part planning, shop documentation, resource management and data management and exchange. To prevent these solutions from detailed tool specific information a dedicated [[tool management]]"}},
{"article_title": "Hacktivism", "pageid": "162600", "revid": "1061373356", "timestamp": "2021-12-21T09:19:20Z", "history_paths": [["Hacktivism --- Introduction ---", "Origins and definitions"]], "categories": ["activism by type", "hacking (computer security)", "internet-based activism", "politics and technology", "internet terminology", "2000s neologisms", "culture jamming techniques", "hacker culture", "articles containing video clips"], "heading_tree": {"Hacktivism --- Introduction ---": {"Origins and definitions": {}, "Forms and methods": {}, "Controversy": {}, "Notable hacktivist events": {}, "Notable hacktivist peoples/groups": {"WikiLeaks": {}, "Anonymous": {}, "DkD[||": {}, "LulzSec": {}}, "Related practices": {"Culture jamming": {}, "Media hacking": {}, "Reality hacking": {"In fiction": {}}, "Academic interpretations": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Hacktivism --- Introduction ---|Origins and definitions": "Writer Jason Sack first used the term hacktivism in a 1995 article in conceptualizing [[new media art|New Media]] artist [[Shu Lea Cheang]]'s film ''[[Fresh Kill]]''.<ref>{{cite magazine|last=Logan|first=Jason|date=November 1995|title=Take the Skinheads Bowling|url=http://info-nation.com/skinhead.html|url-status=dead|magazine=InfoNation|location=Minneapolis|publisher=InfoNation Magazine, Inc.|archive-url=https://web.archive.org/web/19970207061623/http://info-nation.com/skinhead.html|archive-date=7 February 1997|access-date=3 June 2019}}</ref><ref>{{cite journal|last1=Webber|first1=Craig|last2=Yip|first2=Michael|date=June 2018|title=The Rise of Chinese Cyber Warriors: Towards a Theoretical Model of Online Hacktivism|url=https://www.cybercrimejournal.com/Webber&YipVol12Issue1IJCC2018.pdf|journal=International Journal of Cyber Criminology|volume=12|issue=1|page=230}}</ref> However, the term is frequently attributed to the [[Cult of the Dead Cow]] (cDc) member "Omega," who used it in a 1996 e-mail to the group.<ref name=":5">{{Cite book|last1=Shantz|first1=Jeff|url=https://books.google.com/books?id=nRjtBAAAQBAJ|title=Cyber Disobedience: Re://Presenting Online Anarchy|last2=Tomblin|first2=Jordon|date=2014-11-28|publisher=John Hunt Publishing|isbn=9781782795551|archive-url=https://web.archive.org/web/20151116134639/https://books.google.com/books?id=nRjtBAAAQBAJ|archive-date=2015-11-16|url-status=live}}</ref><ref>{{cite web|last=Mills|first=Elinor|date=30 March 2012|title=Old-time hacktivists: Anonymous, you've crossed the line|url=https://www.cnet.com/news/old-time-hacktivists-anonymous-youve-crossed-the-line/|access-date=3 June 2019|website=CNet|publisher=CNet}}</ref> Due to the variety of meanings of its root words, the definition of hacktivism is nebulous and there exists significant disagreement over the kinds of activities and purposes it encompasses. Some definitions include acts of [[cyberterrorism]] while others simply reaffirm the use of technological hacking to effect social change.<ref>Peter Ludlow [http://opinionator.blogs.nytimes.com/2013/01/13/what-is-a-hacktivist/ "What is a 'Hacktivist'?"] {{webarchive|url=https://web.archive.org/web/20130521020503/http://opinionator.blogs.nytimes.com/2013/01/13/what-is-a-hacktivist/|date=2013-05-21}} The New York Times. January 2013.</ref><ref>{{Cite web|last=Jordon|first=Tomblin|date=2015-01-01|title=The Rehearsal and Performance of Lawful Access|url=https://curve.carleton.ca/4c458bdb-33fb-42b1-bf6b-a390e973c792|url-status=live|archive-url=https://web.archive.org/web/20160203055526/https://curve.carleton.ca/4c458bdb-33fb-42b1-bf6b-a390e973c792|archive-date=2016-02-03|access-date=2016-01-16|website=curve.carleton.ca}}</ref>"}},
{"article_title": "Oil platform", "pageid": "163806", "revid": "1058383171", "timestamp": "2021-12-03T05:17:26Z", "history_paths": [["Oil platform --- Introduction ---", "History"]], "categories": ["oil platforms", "offshore engineering", "petroleum production", "drilling technology", "natural gas technology", "structural engineering"], "heading_tree": {"Oil platform --- Introduction ---": {"History": {}, "Main offshore basins": {}, "Types": {"Fixed platforms": {}, "Compliant towers": {}, "Semi-submersible platform": {}, "Jack-up drilling rigs": {}, "Drillships": {}, "Floating production systems": {}, "Tension-leg platform": {}, "Gravity-based structure": {}, "Spar platforms": {}, "Normally unmanned installations (NUI)": {}, "Conductor support systems": {}}, "Particularly large examples": {}, "Maintenance and supply": {}, "Crew": {"Essential personnel": {}, "Incidental personnel": {}}, "Drawbacks": {"Risks": {}, "Ecological effects": {}}, "Effects on the environment": {}, "Repurposing": {}, "Challenges": {}, "Deepest Platforms": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Oil platform --- Introduction ---|History": "[[File:Gulf Offshore Platform.jpg|thumb|upright|Offshore platform, [[Gulf of Mexico]]]]\nAround 1891, the first submerged oil wells were drilled from platforms built on piles in the fresh waters of the [[Grand Lake St. Marys]] (a.k.a. Mercer County Reservoir) in [[Ohio]]. The wide but shallow reservoir was built from 1837 to 1845 to provide water to the [[Miami and Erie Canal]].\n\nAround 1896, the first submerged oil wells in salt water were drilled in the portion of the [[Summerland Oil Field|Summerland field]] extending under the [[Santa Barbara Channel]] in [[California]]. The wells were drilled from piers extending from land out into the channel.\n\nOther notable early submerged drilling activities occurred on the Canadian side of [[Lake Erie]] since 1913  and [[Caddo Lake]] in [[Louisiana]] in the 1910s. Shortly thereafter, wells were drilled in tidal zones along the [[Gulf Coast of the United States|Gulf Coast]] of [[Texas]] and Louisiana. The [[Goose Creek Oil Field|Goose Creek field]] near [[Baytown, Texas]] is one such example. In the 1920s, drilling was done from concrete platforms in [[Lake Maracaibo]], [[Venezuela]].\n\nThe oldest offshore well recorded in Infield's offshore database is the [[Bibiheyb\u0259t|Bibi Eibat]] well which came on stream in 1923 in [[Azerbaijan]].<ref>{{cite web|url=http://www.members.tripod.com/azmsa/oil.html|title=Oil in Azerbaijan|access-date=20 April 2015|archive-date=27 April 2015|archive-url=https://web.archive.org/web/20150427111525/http://www.members.tripod.com/azmsa/oil.html|url-status=live}}</ref> Landfill was used to raise shallow portions of the [[Caspian Sea]].\n\nIn the early 1930s, [[Texaco|the Texas Company]] developed the first mobile steel barges for drilling in the brackish coastal areas of the gulf.\n\nIn 1937, [[Pure Oil Company]] (now [[Chevron Corporation]]) and its partner [[Superior Oil Company]] (now part of [[ExxonMobil Corporation]]) used a fixed platform to develop a field in {{convert|14|ft|m}} of water, one mile (1.6 km) offshore of [[Calcasieu Parish, Louisiana]].\n\nIn 1938, Humble Oil built  a mile-long wooden trestle with railway tracks into the sea at McFadden Beach on the Gulf of Mexico, placing a derrick at its end \u2013 this was later destroyed by a hurricane.<ref>{{cite journal|last1=Morton|first1=Michael Quentin|date=June 2016|title=Beyond Sight of Land: A History of Oil Exploration in the Gulf of Mexico|url=https://www.academia.edu/25960555|journal=GeoExpro|volume=30|issue=3|pages=60\u201363|access-date=8 November 2016|archive-date=8 August 2021|archive-url=https://web.archive.org/web/20210808034610/https://www.academia.edu/25960555|url-status=live}}</ref>\n\nIn 1945, concern for American control of its offshore oil reserves caused President [[Harry Truman]] to issue an Executive Order unilaterally extending American territory to the edge of its continental shelf, an act that effectively ended the [[3-mile limit]] "[[freedom of the seas]]" regime.\n\nIn 1946, Magnolia Petroleum (now [[ExxonMobil]]) drilled at a site {{convert|18|mi|km}} off the coast, erecting a platform in {{convert|18|ft|m}} of water off [[St. Mary Parish, Louisiana]].\n\nIn early 1947, Superior Oil erected a drilling/production platform in {{convert|20|ft|m|abbr=on}} of water some 18 miles{{vague|which miles?|date=February 2010}} off [[Vermilion Parish, Louisiana]]. But it was [[Kerr-McGee]] Oil Industries (now part of [[Occidental Petroleum]]), as operator for partners [[Phillips Petroleum]] ([[ConocoPhillips]]) and [[Stanolind Oil & Gas]] ([[BP]]), that completed its historic Ship Shoal Block 32 well in October 1947, months before Superior actually drilled a discovery from their Vermilion platform farther offshore. In any case, that made Kerr-McGee's well the first oil discovery drilled out of sight of land.<ref>Ref accessed 02-12-89 by technical aspects and coast mapping. [[Kerr-McGee]]</ref><ref name="project-redsand">{{Cite web|url=http://www.project-redsand.com/|title=Project Redsand CIO | Protecting The Redsand Towers|access-date=2007-06-16|archive-date=2017-07-02|archive-url=https://web.archive.org/web/20170702061430/http://project-redsand.com/|url-status=live}}</ref>\n\nThe British [[Maunsell Forts]] constructed during [[World War II]] are considered the direct predecessors of modern offshore platforms. Having been pre-constructed in a very short time, they were then floated to their location and placed on the shallow bottom of the [[Thames]] and the [[Mersey]] estuary.<ref name="project-redsand" /><ref>{{Cite magazine|magazine=Azerbaijan International|volume=11|issue=2|pages=56\u201363|url=http://www.azer.com/aiweb/categories/magazine/ai112_folder/112_articles/112_chronology.html|title=Azerbaijan's Oil History: Brief Oil Chronology since 1920 Part 2|author=Mir-Yusif Mir-Babayev|date=Summer 2003|access-date=2006-11-01|archive-date=2016-03-03|archive-url=https://web.archive.org/web/20160303185344/http://azer.com/aiweb/categories/magazine/ai112_folder/112_articles/112_chronology.html|url-status=live}}</ref>\n\nIn 1954, the first [[jackup rig|jackup oil rig]] was ordered by [[Zapata Oil]]. It was designed by [[R. G. LeTourneau]] and featured three electro-mechanically-operated lattice-type legs. Built on the shores of the [[Mississippi river]] by the LeTourneau Company, it was launched in December 1955, and christened "Scorpion". The Scorpion was put into operation in May 1956 off [[Port Aransas]], Texas. It was lost in 1969.<ref>{{Cite web |url=http://iadc.org/dcpi/dc-septoct05/Sept05-anniversary.pdf |title=Archived copy |access-date=2017-05-01 |archive-date=2017-10-31 |archive-url=https://web.archive.org/web/20171031112929/http://iadc.org/dcpi/dc-septoct05/Sept05-anniversary.pdf |url-status=live }}</ref><ref>{{Cite web|url=http://petrowiki.org/History_of_offshore_drilling_units|title=History of offshore drilling units \u2013 PetroWiki|website=petrowiki.org|access-date=2017-05-01|archive-date=2017-03-22|archive-url=https://web.archive.org/web/20170322213629/http://petrowiki.org/History_of_offshore_drilling_units|url-status=live}}</ref><ref>{{Cite web|url=https://www.youtube.com/watch?v=4ibvuWmF7Dc|title=YouTube|website=www.youtube.com|access-date=2017-05-01|archive-date=2014-05-10|archive-url=https://web.archive.org/web/20140510100159/http://www.youtube.com/watch?v=4ibvuWmF7Dc&gl=US&hl=en|url-status=live}}</ref>\n\nWhen offshore drilling moved into deeper waters of up to {{convert|30|m|ft}}, fixed platform rigs were built, until demands for drilling equipment was needed in the {{convert|30|m|ft}} to {{convert|120|m|ft}} depth of the Gulf of Mexico, the first [[Jackup rig|jack-up rigs]] began appearing from specialized offshore drilling contractors such as forerunners of ENSCO International.\n\nThe first [[semi-submersible]] resulted from an unexpected observation in 1961. [[Blue Water Drilling Company]] owned and operated the four-column submersible Blue Water Rig No.1 in the Gulf of Mexico for [[Shell Oil Company]]. As the pontoons were not sufficiently buoyant to support the weight of the rig and its consumables, it was towed between locations at a draught midway between the top of the pontoons and the underside of the deck. It was noticed that the motions at this draught were very small, and Blue Water Drilling and Shell jointly decided to try operating the rig in its floating mode. The concept of an anchored, stable floating deep-sea platform had been designed and tested back in the 1920s by [[Edward Robert Armstrong]] for the purpose of operating aircraft with an invention known as the "seadrome". The first purpose-built drilling [[semi-submersible]] ''Ocean Driller'' was launched in 1963. Since then, many semi-submersibles have been purpose-designed for the drilling industry mobile offshore fleet.\n\nThe first offshore [[drillship]] was the ''CUSS 1'' developed for the [[Mohole]] project to drill into the Earth's crust.\n\nAs of June, 2010, there were over 620 mobile offshore drilling rigs (Jackups, semisubs, drillships, barges) available for service in the competitive rig fleet.<ref>{{cite web|url=http://www.rigzone.com/data/|title=RIGZONE \u2013 Offshore Rig Data, Onshore Fleet Analysis|access-date=20 April 2015|archive-url=https://web.archive.org/web/20150408021427/http://www.rigzone.com/data/|archive-date=8 April 2015|url-status=dead}}</ref>\n\nOne of the world's deepest hubs is currently the [[Perdido oil platform|Perdido]] in the Gulf of Mexico, floating in 2,438 meters of water. It is operated by [[Royal Dutch Shell]] and was built at a cost of $3 billion.<ref name= UPDATE1>{{cite web|date=March 31, 2010|url=https://www.reuters.com/article/idUSN3123683920100331|title=UPDATE 1-Shell starts production at Perdido|work=Reuters|access-date=20 April 2015|archive-date=21 November 2010|archive-url=https://web.archive.org/web/20101121070821/http://www.reuters.com/article/idUSN3123683920100331|url-status=live}}</ref> The deepest operational platform is the Petrobras America Cascade FPSO in the Walker Ridge 249 field in 2,600 meters of water."}},
{"article_title": "Food coloring", "pageid": "164956", "revid": "1052340683", "timestamp": "2021-10-28T16:47:37Z", "history_paths": [["Food coloring --- Introduction ---", "History of artificial food colorants"]], "categories": ["food additives", "food technology", "food colorings"], "heading_tree": {"Food coloring --- Introduction ---": {"Purpose of food coloring": {}, "History of artificial food colorants": {}, "Regulation": {"History of regulation": {}, "Current regulation": {}, "Permitted colorants": {"E.U.": {}, "U.S.": {}, "India": {}}, "Global harmonization": {}}, "Natural food dyes": {}, "Criticism and health implications": {}, "Chemical structures of representative colorants": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Food coloring --- Introduction ---|History of artificial food colorants": "The addition of colorants to foods is thought to have occurred in Egyptian cities as early as 1500 BC, when candy makers added natural extracts and wine to improve the products' appearance.<ref>{{cite encyclopedia |author= Meggos, H. |title= Food colours: an international perspective |encyclopedia= The Manufacturing Confectioner |pages= 59\u201365 |year= 1995 }}</ref> During the [[Middle Ages]], the economy in the European countries was based on agriculture, and the peasants were accustomed to producing their own food locally or trading within the village communities. Under feudalism, aesthetic aspects were not considered, at least not by the vast majority of the generally very poor population.<ref name="Arlt">{{cite web |last= Arlt |first= Ulrike |title= The Legislation of Food Colours in Europe |publisher= The Natural Food Colours Association |date= 29 Apr 2011 |url= http://www.natcol.org/node/19 |access-date= 18 Feb 2014}}</ref> This situation changed with urbanization at the beginning of the [[Modern Age]], when trade emerged\u2014especially the import of precious spices and colors. One of the first food laws, created in Augsburg, Germany, in 1531, concerned spices or colorants and required [[saffron]] counterfeiters to be [[Death by burning|burned]].<ref name="cook">{{cite journal |last= Cook |first= Jim |title= Colorants Compliance |journal= The World of Food Ingredients |issue= Sept 2013 |pages= 41\u201343 |issn= 1566-6611 }}<!--|access-date= 18 Feb 2014--></ref>\n\n[[File:Margarine.jpg|thumb|The addition of food coloring, such as [[beta-carotene]], gives naturally white [[margarine]] a yellow, butter-like color.<ref>Ian P. Freeman, "Margarines and Shortenings" Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim {{DOI|10.1002/14356007.a16_145}}</ref><ref name="rupp">{{cite web|author1=Rupp R|title=The Butter Wars: When Margarine Was Pink|url=http://theplate.nationalgeographic.com/2014/08/13/the-butter-wars-when-margarine-was-pink/|publisher=The Plate: National Geographic|access-date=10 November 2020|date=13 August 2014}}</ref>]]\nWith the onset of the industrial revolution, people became dependent on foods produced by others.<ref name="Arlt" /> These new urban dwellers demanded food at low cost. Analytical chemistry was still primitive and regulations few. The [[Adulterated food|adulteration of foods]] flourished.<ref name="Arlt" /> Heavy metal and other inorganic element-containing compounds turned out to be cheap and suitable to "restore" the color of watered-down milk and other foodstuffs, some more lurid examples being:<ref name="a">{{cite journal |last1= Downham |first1= Alison |last2= Collins |first2= Paul |title= Colouring our foods in the last and next millennium |journal= International Journal of Food Science and Technology |volume= 35 |pages= 5\u201322 |year= 2000 |access-date= 18 Feb 2014 |url= http://www.blacksci.co.uk/products/journals/freepdf/tmp1.pdf |doi= 10.1046/j.1365-2621.2000.00373.x |citeseerx= 10.1.1.466.4598 |archive-url= https://web.archive.org/web/20140811180953/http://www.blacksci.co.uk/products/journals/freepdf/tmp1.pdf |archive-date= 11 August 2014 |url-status= dead }}</ref>\n* [[Red lead]] (Pb<sub>3</sub>O<sub>4</sub>) and [[Cinnabar|vermillion]] (HgS) were routinely used to color cheese and confectionery.\n* [[Copper arsenite]] (CuHAsO<sub>3</sub>) was used to recolor used tea leaves for resale. It also caused two deaths when used to color a dessert in 1860.\n\nSellers at the time offered more than 80 artificial coloring agents, some invented for dyeing textiles, not foods.<ref name="a" /> {{quote|Thus, with potted meat, fish and sauces taken at breakfast he would consume more or less [[Armenian bole]], red lead, or even bisulphuret of mercury [vermillion, HgS]. At dinner with his curry or cayenne he would run the chance of a second dose of lead or mercury; with pickles, bottled fruit and vegetables he would be nearly sure to have copper administrated to him; and while he partook of bon-bons at dessert, there was no telling of the number of poisonous pigments he might consume. Again his tea if mixed or green, he would certainly not escape without the administration of a little [[Prussian blue]]...<ref>{{cite book |last= Hassel |first= A.H. |editor-last= Amos |editor-first= Arthur James |title= Pure Food and Pure Food Legislation |location= Butterworths, London |year= 1960 |page= 12 |url= https://books.google.com/books?id=3KI1AQAAIAAJ }}</ref>}} Many color additives had never been tested for toxicity or other adverse effects. Historical records show that injuries, even deaths, resulted from tainted colorants. In 1851, about 200 people were poisoned in England, 17 of them fatally, directly as a result of eating adulterated [[throat lozenge|lozenges]].<ref name="Arlt" /> In 1856, [[mauveine]], the first [[Synthetic dye#Synthetic dye|synthetic color]], was developed by [[Sir William Henry Perkin]] and by the turn of the century, unmonitored color additives had spread through Europe and the United States in all sorts of popular foods, including ketchup, mustard, jellies, and wine.<ref>{{cite journal |last= Walford |first= J. |title= Historical Development of Food Colouration |journal= Developments in Food Colours |volume= 1 |pages= 1\u201325 |publisher= Applied Science Publishers |location= London |year= 1980 }}</ref><ref>{{cite journal|title=A Global Perspective on the History, Use, and Identification of Synthetic Food Dyes|author1=Sharma, Vinita|author2=McKone, Harold T.|author3=Markow, Peter G.|journal=Journal of Chemical Education|year=2011|volume=88|pages=24\u201328|doi=10.1021/ed100545v}}</ref> Originally, these were dubbed 'coal-tar' colors because the starting materials were obtained from [[bituminous coal]].<ref>{{cite web|last=Hancock|first=Mary|title=Potential for Colourants from Plant Sources in England & Wales|url=http://ienica.csl.gov.uk/usefulreports/colourants.pdf|work=UK Central Science Laboratory|access-date=20 January 2013|year=1997|quote=The use of natural dyes in the UK and the rest of the Western economies has been replaced commercially by synthetic dyes, based mainly on aniline and using petroleum or coal tar as the raw stock.|archive-url=https://web.archive.org/web/20130513035834/http://ienica.csl.gov.uk/usefulreports/colourants.pdf|archive-date=13 May 2013|url-status=dead}}</ref><ref name="Barrows">{{cite web |last1=Barrows |first1=Julie N. |last2=Lipman |first2=Arthur L. |last3=Bailey |first3=Catherine J. |title= Color Additives: FDA's Regulatory Process and Historical Perspectives |publisher= FDA (Reprinted from Food Safety Magazine October/November 2003 issue) |date= 17 Dec 2009 |url= https://www.fda.gov/ForIndustry/ColorAdditives/RegulatoryProcessHistoricalPerspectives/default.htm |access-date= 2 Mar 2012|quote=Although certifiable color additives have been called coal-tar colors because of their traditional origins, today they are synthesized mainly from raw materials obtained from petroleum.}}</ref>\n\nSynthetic dyes are often less costly and technically superior to natural dyes.<ref name="a" /><ref name=Azodye>{{Ullmann|first1 = Klaus|last1 = Hunger|first2 = Peter|last2 = Mischke|first3 = Wolfgang|last3 = Rieper|first4 = Roderich|last4 = Raue|first5 = Klaus|last5 = Kunde|first6 = Aloys|last6 = Engel|display-authors=3|title = Azo Dyes|year = 2005|doi = 10.1002/14356007.a03_245}}</ref><ref name=JK>{{Citation |last= K\u00f6nig |first= J. |editor-last= Scotter |editor-first= Michael J. |title= Colour Additives for Foods and Beverages |publisher= Elsevier |year= 2015 |chapter= Food colour additives of synthetic origin |pages= 35\u201360 |doi= 10.1016/B978-1-78242-011-8.00002-7 |isbn= 978-1-78242-011-8 }}</ref>"}},
{"article_title": "Hydrometer", "pageid": "165194", "revid": "1053827878", "timestamp": "2021-11-06T09:20:06Z", "history_paths": [["Hydrometer --- Introduction ---", "History"]], "categories": ["ancient roman technology", "brewing", "laboratory equipment", "laboratory glassware", "density meters"], "heading_tree": {"Hydrometer --- Introduction ---": {"History": {}, "Ranges": {}, "Scales": {}, "Specialized hydrometers": {"Alcoholometer": {}, "Lactometer": {}, "Saccharometer": {}, "Thermohydrometer": {}, "Battery hydrometer": {}, "Antifreeze tester": {}, "Acidometer": {}, "Barkometer": {}, "Salinometer": {}, "Urinometer": {}, "Gallery": {}}, "Use in soil analysis": {}, "See also": {}, "References": {}, "Sources": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Hydrometer --- Introduction ---|History": "[[File : Hydrometer6455.png|thumb|upright=0.6|Hydrometer from Practical Physics]]\n\nThe hydrometer probably dates  back to the Greek philosopher [[Archimedes]] (3rd century BC) who used its principles to find the density of various liquids.<ref>Ian Spencer Hornsey, A history of beer and brewing, Royal Society of Chemistry \u00b7 2003, page 429</ref><ref>Jeanne Bendick, Archimedes and the Door of Science, Literary Licensing, LLC \u00b7 2011, pages 63-64</ref> An early description of a hydrometer comes from a Latin poem, written in the 2nd century AD by Remnius, who compared the use of a hydrometer to the method of [[Displacement (fluid)|fluid displacement]] used by Archimedes to determine the gold content of [[Hiero II of Syracuse|Hiero II's]] crown.<ref name="bensaude-vincent">{{cite book |last=Bensaude-Vincent |first=Bernadette |author-link=Bernadette Bensaude-Vincent |editor1-last=Holmes |editor1-first=Frederic L. |editor2-last=Levere |editor2-first=Trevor H. |date=2002 |title=Instruments and Experimentation in the History of Chemistry |publisher=Massachusetts Institute of Technology Press |page=153}}</ref>\n\n[[Hypatia of Alexandria]] (4th-5th century AD), an important female Greek mathematician, is the first person traditionally associated with the hydrometer.<ref name="bensaude-vincent"/> In a letter, [[Synesius|Synesius of Cyrene]] asks Hypatia, his teacher, to make a hydrometer for him:\n\n<blockquote>\nThe instrument in question is a cylindrical tube, which has the shape of a flute and is about the same size. It has notches in a perpendicular line, by means of which we are able to test the weight of the waters. A cone forms a lid at one of the extremities, closely fitted to the tube. The cone and the tube have one base only. This is called the baryllium. Whenever you place the tube in water, it remains erect. You can then count the notches at your ease, and in this way ascertain the weight of the water.<ref>{{cite book |last=FitzGerald |first=Augustine |date=1926 |title=The Letters of Synesius of Cyrene |publisher=Oxford University Press |page=Letter 15}}</ref>\n</blockquote>\n\nAccording to the ''Encyclopedia of the History of Arabic Science'', it was used by [[Ab\u016b Rayh\u0101n al-B\u012br\u016bn\u012b]] in the 11th century and described by [[Al-Khazini]] in the 12th century.<ref>{{cite book |author1=Mariam Rozhanskaya |name-list-style=amp |author2=I. S. Levinova |chapter=Statics |chapter-url=https://books.google.com/books?id=Dy897SeErOQC&pg=PA614 |editor1=Rushd\u012b R\u0101shid |editor2=R\u00e9gis Morelon |year=1996 |title=[[Encyclopedia of the History of Arabic Science|Encyclopedia of the History of Arabic Science, Volume 2]] |publisher=[[Routledge]] |isbn=978-0-415-12411-9 |pages=614\u2013642 [ [https://books.google.com/books?id=Dy897SeErOQC&pg=PA639#v=onepage&q&f=false 639] ] |access-date=2019-03-26}}</ref> It was rediscovered in 1612 by Galileo and his circle of friends, and used in experiments especially at the Accademia del Cimento.<ref>{{cite web|title=Museo Galileo |url=https://catalogue.museogalileo.it/indepth/Hydrometer.html}}</ref> It appeared again in the 1675 work of Robert Boyle (who coined the name ''"hydrometer"''),<ref name="bensaude-vincent">{{cite book |last=Bensaude-Vincent |first=Bernadette |author-link=Bernadette Bensaude-Vincent |editor1-last=Holmes |editor1-first=Frederic L. |editor2-last=Levere |editor2-first=Trevor H. |date=2002 |title=Instruments and Experimentation in the History of Chemistry |publisher=Massachusetts Institute of Technology Press |page=153}}</ref> with types devised by [[Antoine Baum\u00e9]] (the [[Baum\u00e9 scale]]), [[William Nicholson (chemist)|William Nicholson]], and [[Jacques Charles|Jacques Alexandre C\u00e9sar Charles]] in the late 18th century,<ref>{{cite journal |author=Claude-Joseph Blondel |url=https://gallica.bnf.fr/ark:/12148/bpt6k65454933 |title=Un enfant illustre de Beaugency : le physicien et a\u00e9ronaute Jacques Charles (1746-1823) |journal=Les Publications de l'Acad\u00e9mie d'Orl\u00e9ans, Agriculture, Sciences, Belles-lettres et Arts |number=4 |publisher=Acad\u00e9mie d'Orl\u00e9ans |year=2003 |page=37}}</ref> more or less contemporarily with [[Benjamin Sikes]]' discovery of the device by which the alcoholic content of a liquid can be automatically determined. The use of the Sikes device was made obligatory by British law in 1818.<ref>{{harvnb|Denison|1955|p=132}}</ref>"}},
{"article_title": "PARAM", "pageid": "165299", "revid": "1061833242", "timestamp": "2021-12-24T08:03:09Z", "history_paths": [["PARAM --- Introduction ---", "History"]], "categories": ["supercomputers", "information technology in india", "supercomputing in india"], "heading_tree": {"PARAM --- Introduction ---": {"History": {"PARAM 8000": {"Exports": {}}, "PARAM 8600": {}, "PARAM 9000": {}, "PARAM 10000": {}, "PARAM Padma": {}, "PARAM Yuva": {}, "Param Yuva II": {}, "PARAM ISHAN": {}, "PARAM Brahma": {}, "PARAM Siddhi-AI": {}, "PARAM Shivay": {}, "PARAM Sanganak": {}}, "Supercomputer summary": {}, "PARAMNet": {}, "Operators": {}, "See also": {}, "Notes": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"PARAM --- Introduction ---|History": "{{see|Supercomputing in India}}\nC-DAC was created in November 1987, originally as the Centre for Development of Advanced Computing Technology (C-DACT).<ref name="1989-delapierre" /> This was in response to issues purchasing supercomputers from foreign sources.<ref name="2004-sinha" /> The Indian Government decided to try and develop indigenous computing technology.<ref name=1999-bbc />\n\n The PARAM 8000 was the first machine in the series and was built from scratch.<ref name="1996-kahaner" /> A [[prototype]] was [[Benchmark (computing)|benchmarked]] at the "1990 Zurich Super-computing Show":<ref group="note">This is likely the CONPAR 90 - VAPP IV, Joint International Conference on Vector and Parallel Processing, which took place in Zurich, Switzerland, 10\u201313 September  1990. The statement is difficult to fully attest to other than the referenced article. The proceedings of the conference can be found at https://doi.org/10.1007/3-540-53065-7</ref> of the machines that ran at the show it came second only to one from the United States.<ref name=1998-outlook />\n\nA 64-node machine was delivered in August 1991.<ref name="1996-kahaner" /><ref name="UNIDO" /> Each node used [[Inmos]] T800/T805 [[transputer]]s.<ref name="UNIDO" /> A 256-node machine had a theoretical performance of 1GFLOPS, however in practice had a sustained performance of 100-200MFLOPS.<ref name="UNIDO" /><ref name="1996-kahaner" /> PARAM 8000 was a [[distributed memory]] [[MIMD]] architecture with a reconfigurable interconnection network.<ref name=1997-marvin />\n\nThe PARAM 8000 was noted to be 28 times more powerful than the Cray X-MP that the government originally requested, for the same $10 million cost quoted for it. <ref name="supercomp">{{cite book|url=https://books.google.com/books?id=y9Nxe0SPeVkC|title=Super Computers|last=Rajaraman|first=V.|publisher=Universities Press|year=1999|page=75|access-date=15 September 2011|isbn=9788173711497}}</ref>\n\n The computer was a success and was exported to Germany, United Kingdom and Russia.<ref>{{cite web|url=http://www.thehindubusinessline.com/2001/02/26/stories/102618ma.htm |title=''Only protected usable knowledge can create wealth.'' |publisher=Thehindubusinessline.com |date=26 February 2001 |access-date=10 September 2016}}</ref> Apart from taking over the home market, PARAM attracted 14 other buyers with its relatively low price tag of $350,000.<ref name="Washington Post Archive">{{cite web |url=https://www.washingtonpost.com/archive/business/1993/03/19/cray-deal-a-casualty-of-atomic-weapon-fears/24f11e87-effe-4a2c-8976-d3d844cb4275/ |title=CRAY DEAL A CASUALTY OF ATOMIC WEAPON FEARS|newspaper=The Washington Post}}</ref>\n\nThe computer was also exported to the ICAD [[Moscow]] in 1991 under [[Russia]]n collaboration.<ref>{{cite web |url=http://www.cdac.in/html/about/success/moscow.aspx |title=C-DAC furthering ties with ICAD, Moscow: From PARAM 8000 to PARAM 10000|publisher=Center for Development of Advanced Computing (C-DAC) |access-date=15 September 2011 }}</ref><ref>{{cite web |url=http://www.cdac.in/html/press/1q06/spot563.aspx |title=Supercomputer being developed at Pune, Bangalore will be ready in 6 months| quote=...giving India her first indigenous supercomputer in 1991 (PARAM 8000)|publisher=Center for Development of Advanced Computing (C-DAC) |access-date=15 September 2011 }}</ref><ref>{{cite web|url=https://cdac.in/index.aspx?id=aboutus_digital_india_week|title=Digital India Week}}</ref><ref>{{Cite news|url=http://www.thebetterindia.com/82076/india-first-supercomputer-param-cdac-vijay-bhatkar/|title=The Little Known Story of How India's First Indigenous Supercomputer Amazed the World in 1991|date=13 January 2017|work=The Better India|language=en-US}}</ref>\n\n PARAM 8600 was an improvement over PARAM 8000. In 1992 C-DAC realised its machines were underpowered and wished to integrate the newly released [[Intel i860]] processor.<ref name="1994-bhatkar" /> Each node was created with one i860 and four Inmos T800 transputers.<ref name=1997-marvin /><ref name="1996-kahaner" /><ref name="UNIDO" /> The same PARAS programming environment was used for both the PARAM 8000 and 8600; this meant that programs were portable.<ref name="1996-kahaner" /><ref name="UNIDO" /> Each 8600 cluster was noted to be as powerful as 4 PARAM 8000 clusters.<ref name="UNIDO" />\n\n The PARAM 9000 was designed to be merge [[Computer cluster|cluster processing]] and [[Massively parallel (computing)|massively parallel processing]] computing workloads.<ref name="mohan-param9000" /> It was first demonstrated in 1994.<ref name="2004-sinha" /> The design was changed to be modular so that newer processors could be easily accommodated.<ref name=1997-marvin /> Typically a system used 32\u201340 processors, however it could be scaled up to 200 CPUs using the [[clos network]] topology.<ref name=1997-marvin /> The PARAM 9000/SS was the [[SuperSPARC|SuperSPARC II]] processor variant,<ref name="1995-van-der-steen" /> the PARAM 9000/US used the [[UltraSPARC]] processor,{{citation-needed|date=July 2020}} and the PARAM 9000/AA used the [[DEC Alpha]].<ref name="1996-harkar" />\n\n The PARAM 10000 was unveiled in 1998 as part of C-DAC's second mission.<ref name="2004-sinha" /> PARAM 10000 used several independent nodes, each based on the [[Sun Enterprise|Sun Enterprise 250]] server; each such server contained two 400[[Mhz]] [[UltraSPARC|UltraSPARC II]] processors. The base configuration had three compute nodes and a server node. The peak speed of this base system was 6.4 [[FLOPS|GFLOPS]].<ref>{{cite book | last1=Abraham| last2= Baets|last3=K\u00f6ppen| url=https://books.google.com/books?id=xYgCFX6VnT8C&q=param%2010000&pg=PA54|publisher=Springer| year=2006| title=Applied soft computing technologies: the challenge of complexity| page=54| access-date=15 September 2011| isbn= 9783540316626}}</ref> A typical system would contain 160 [[CPU]]s and be capable of 100 [[FLOPS|GFLOPS]]<ref name=bram>{{cite book | last=Ram| first= B.| url=https://books.google.com/books?id=ICjqr6V9S6UC&q=param%20padma&pg=SA1-PA20|publisher=New Age International| title=Computer Fundamentals, Architecture & Organisation| pages=1\u201320| access-date=15 September 2011| isbn= 9788122420432| date= December 2009}}</ref> But, it was easily scalable to the [[FLOPS|TFLOP]] range. Exported to Russia and Singapore.<ref>{{cite web|url=http://www.rediff.com/computer/1999/sep/28param.htm|title=Rediff on the Net, Infotech: Exporting speed|date=28 September 1999|work=Rediff.com|access-date=10 September 2016}}</ref>\n\n PARAM Padma (''Lotus'' in Sanskrit) was introduced in December 2002.<ref name="2004-sinha" /> It had a peak speed of 1024 GFLOPS (about 1 TFLOPS).{{citation-needed|date=July 2020}} The machine used IBM [[POWER4]] processors.<ref name="2004-sinha" /> PARAM Padma was the first Indian machine ranked on a  worldwide supercomputer list.<ref name="2004-sinha" />\n\n PARAM Yuva (''Youth'' in Sanskrit) was unveiled in November 2008. It has a maximum sustainable speed (Rmax) of 38.1 TFLOPS and a peak speed (Rpeak) of 54 TFLOPS.<ref name=top500yuva>{{cite web|url=http://www.top500.org/system/performance/9746|title=Top500: "PARAM Yuva" Cluster (Performance)|access-date=15 September 2011}}</ref> There are 4608 cores in it, based on [[Tigerton (microprocessor)#Tigerton|Intel 73XX]] of 2.9 GHz each. It has a storage capacity of 25 TB up to 200 TB.<ref name="pri"/> It uses PARAMNet-3 as its primary interconnect.\n\n PARAM Yuva II was unveiled on 8 February 2013. It was created in three months at a cost of {{INRConvert|160|m|0}}. It performs at a peak of 524 TFLOPS, about 10 times faster than the present facility, and will consume 35% less energy as compared to the existing facility. According to CDAC, the supercomputer can deliver sustained performance of 360.8 TFLOPS on the community standard [[LINPACK]] benchmark.<ref name=iw9f>{{cite news|title=C-DAC launches India's fastest supercomputer; becomes first R&D institution in India to cross 500 teraflops milestone|url=http://www.informationweek.in/software/13-02-09/c-dac_launches_india_s_fastest_supercomputer_becomes_first_r_d_institution_in_india_to_cross_500_teraflops_milestone.aspx|access-date=9 February 2013|newspaper=Information Week|date=9 February 2013|url-status=dead|archive-url=https://web.archive.org/web/20130213082334/http://www.informationweek.in/software/13-02-09/c-dac_launches_india_s_fastest_supercomputer_becomes_first_r_d_institution_in_india_to_cross_500_teraflops_milestone.aspx|archive-date=13 February 2013|df=dmy-all}}</ref><ref name=cdag9f>{{cite web|title=C-DAC reaffirms India's position on supercomputing map with PARAM Yuva - II|url=http://www.cdac.in/index.aspx?id=pk_pr_prs_rl210|publisher=CDAC|access-date=9 February 2013}}</ref> It is the first Indian supercomputer achieving more than 500 teraflops.<ref name=toi9f>{{cite web|title=C-DAC unveils India's fastest supercomputer|url=http://articles.timesofindia.indiatimes.com/2013-02-09/infrastructure/37007113_1_petaflop-supercomputer-dac|archive-url=https://web.archive.org/web/20130602020130/http://articles.timesofindia.indiatimes.com/2013-02-09/infrastructure/37007113_1_petaflop-supercomputer-dac|url-status=dead|archive-date=2 June 2013|work=[[The Times of India]]|access-date=9 February 2013}}</ref><ref name=dnai8f>{{cite news|title=India's fastest supercomputer 'Param Yuva II' unveiled|url=http://www.dnaindia.com/india/report_india-s-fastest-supercomputer-param-yuva-ii-unveiled_1797925|access-date=9 February 2013|newspaper=DNA India|date=8 February 2013}}</ref><ref name=ect9f>{{cite news|title=C-DAC unveils India's fastest supercomputer Param Yuva II|url=http://economictimes.indiatimes.com/tech/hardware/c-dac-unveils-indias-fastest-supercomputer-param-yuva-ii/articleshow/18411041.cms|access-date=9 February 2013|newspaper=The Economic Times|date=9 February 2013}}</ref>\n\n PARAM-ISHAN is a 250 Teraflops capacity hybrid HPC at IIT Guwahati. Hon'ble HRD Minister Prakash Javadekar inaugurated the facility on 19th September 2016.\nIt has total 162 compute Nodes with 300TB of Storage based on lustre parallel file system.\n<ref>{{cite web |title=Technical Information |url=https://cdac.in/index.aspx?id=print_page&print=pk_pr_prs_rl230 |website=CDAC Website for PARAM ISHAN |access-date=16 January 2019}}</ref><ref name=p_ishan_iitg>{{cite web|title = PARAM-Ishan @ IIT Guwahati Official site| url = https://www.iitg.ac.in/param-ishan/index.html|quote = Details of PARAM-Ishan a 250 tfps Hybrid HPCC at IIT Guwahati|access-date=26 November 2018 }}</ref>\n\n It is a supercomputer offering a computational power of 850 TeraFlop with 1 PetaByte storage capacity. It is one of the supercomputers built in India under NSM, co-funded by Ministry of Electronics and Information Technology and Department of Science and Technology. Centre for Development of Advanced Computing (C-DAC) and Indian Institute of Science, Bengaluru, are steering this mission. 'PARAM Brahma' is supported by a first-of-its-kind cooling system called direct contact liquid available in India. This cooling system makes effective use of thermal conductivity of liquids, namely water, in maintaining the temperature of the system during operations.<ref>{{cite web|url=https://indianexpress.com/article/cities/pune/param-brahma-will-allow-scientists-to-address-complex-scientific-problems-6037829/|title=PARAM Brahma will allow scientists to address complex scientific problems|date=29 September 2019}}</ref> As of 2020 it is available at [[IISER Pune]].\n\n PARAM Siddhi-AI is a high performance computing-artificial intelligence (HPC-AI) and by far the fastest supercomputer developed in India with an Rpeak of 5.267 PFlops and 4.6 PFlops Rmax (Sustained). Artificial intelligence aids research in advanced materials, [[computational chemistry]] & astrophysics, health care system, flood forecasting and applications related to [[COVID-19]] through faster simulations, medical imaging and. genome sequencing. In November 2020, PARAM Siddhi-AI ranked 63rd among most powerful supercomputer in the world. It is built on the NVIDIA DGX SuperPOD reference architecture networking along with C-DAC\u2019s indigenously developed HPC-AI engine, software frameworks and cloud platform.<ref name="PARAMSiddhi">{{Cite news|title=Indias AI supercomputer Param Siddhi 63rd among top 500 most powerful non-distributed computer systems in the world|url=https://dst.gov.in/indias-ai-supercomputer-param-siddhi-63rd-among-top-500-most-powerful-non-distributed-computer#:~:text=Param%20Siddhi%2C%20the%20high%20performance,on%2016th%20November%202020.|work=Department of Science and Technology|access-date=2020-12-08}}</ref>\n\n PARAM Shivay is a high-performance high computing cluster with 833 teraflop capacity built at the cost of Rs 32.5 crore under the National Super Computing Mission at IIT-BHU.{{citation needed|date=September 2021}}\n\n PARAM Sanganak\u201d, is established at IIT Kanpur under the build approach of the National Supercomputing Mission with a peak computing power of 1.3 peta FLOPS.<ref>https://www.iitk.ac.in/new/param-sanganak</ref>"}},
{"article_title": "Head transplant", "pageid": "167339", "revid": "1059133842", "timestamp": "2021-12-07T17:22:25Z", "history_paths": [["Head transplant --- Introduction ---", "History"]], "categories": ["organ transplantation", "emerging technologies", "animal head"], "heading_tree": {"Head transplant --- Introduction ---": {"Medical challenges": {}, "History": {}, "Ethics and popular opinion": {}, "Popular culture": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Head transplant --- Introduction ---|History": "[[File:Bundesarchiv Bild 183-61478-0004, Kopftransplantation durch Physiologen Demichow.jpg|thumb|Transplantation of a dog-head performed in the [[GDR]] by Vladimir Demikhov on January 13, 1959]]\n\n[[Alexis Carrel]] was a French surgeon who had developed improved surgical methods to [[Circulatory anastomosis|connect blood vessels]] in the context of [[organ transplantation]]. In 1908 he collaborated with the American [[Charles Claude Guthrie]] to attempt to graft the head of one dog on an intact second dog; the grafted head showed some reflexes early on but deteriorated quickly and the animal was killed after a few hours.<ref name=Lamba2017rev/><ref name = "stiffy">{{cite book| last =Roach| first =Mary| date = 2004| title = Stiff: The Curious Lives of Human Cadavers| publisher = W. W. Norton & Co.| isbn = 978-0393324822| pages = 206\u2013210}}</ref> Carrel's work on organ transplantation later earned a Nobel Prize; Guthrie was probably excluded because of this controversial work on head transplantation.<ref name=Furr2017rev>{{cite journal|last1=Furr|first1=A|last2=Hardy|first2=MA|last3=Barret|first3=JP|last4=Barker|first4=JH|title=Surgical, ethical, and psychosocial considerations in human head transplantation.|journal=International Journal of Surgery (London, England)|date=May 2017|volume=41|pages=190\u2013195|doi=10.1016/j.ijsu.2017.01.077|pmid=28110028|pmc=5490488}}</ref>\n\nIn 1954, [[Vladimir Demikhov]], a [[Soviet Union|Soviet]] surgeon who had done important work to improve [[coronary bypass surgery]], performed an experiment in which he grafted a dog's head and upper body including the front legs, onto another dog; the effort was focused on how to provide blood supply to the donor head and upper body and not on grafting the nervous systems. The dogs generally survived a few days; one survived 29 days. The grafted body parts were able to move and react to stimulus. The animals died due to [[transplant rejection]].<ref name=Lamba2017rev/>\n\nIn the 1950s and '60s, [[immunosuppressive drug]]s and [[organ transplantation]] techniques were developed that eventually made transplantation of kidneys, livers, and other organs standard medical procedures.<ref name=Lamba2017rev/>\n\nIn 1965, [[Robert J. White]] did a series of experiments in which he attempted to graft only the vascular system of isolated dog brains onto existing dogs, to learn how to manage this challenge. He monitored brain activity with EEG and also monitored [[metabolism]], and showed that he could maintain high levels of brain activity and metabolism by avoiding any break in the blood supply. The animals survived between 6 hours and 2 days. In 1970, he did four experiments in which he cut the head off of a monkey and connected the blood vessels of another monkey head to it; he did not attempt to connect the nervous systems. White used [[Deep hypothermic circulatory arrest|deep hypothermia]] to protect the brains during the times when they were cut off from blood during procedure. The recipient bodies had to be kept alive with mechanical ventilation and drugs to stimulate the heart. The grafted heads were able to function - the [[Eye movement|eyes tracked]] moving objects and it could chew and swallow. There were problems with the grafting of blood vessels that led to blood clots forming, and White used high doses of immunosuppressive drugs that had severe side effects; the animals died between 6 hours and 3 days after the heads were engrafted.<ref name=Lamba2017rev/> These experiments were reported and criticized in the media and were considered barbaric by animal rights activists.<ref name=Furr2017rev/> There were few animal experiments on head transplantation for many years after this.<ref name=Furr2017rev/>\n\nIn 2012, [[Xiaoping Ren]] published work in which he grafted the head of a mouse onto another mouse's body; again the focus was on how to avoid harm from the loss of blood supply; with his protocol the grafted heads survived up to six months.<ref name=Lamba2017rev/>\n\nIn 2013, [[Sergio Canavero]] published a protocol that he said would make human head transplantation possible.<ref name=NS>{{cite news|title=Sergio Canavero: Will His Head Transplants Roll? - Neuroskeptic|url=http://blogs.discovermagazine.com/neuroskeptic/2017/05/13/canavero-head-transplants/|work=Neuroskeptic|date=13 May 2017}}</ref><ref name=":0">{{cite journal|last1=Canavero|first1=S|title=HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI).|journal=Surgical Neurology International|date=2013|volume=4|issue=Suppl 1|pages=S335\u201342|pmid=24244881|doi=10.4103/2152-7806.113444|pmc=3821155}}</ref>\n\nIn 2015, Ren published work in which he cut off the heads of mice but left the brain stem in place, and then connected the vasculature of the donor head to the recipient body; this work was an effort to address whether it was possible to keep the body of the recipient animal alive without life support. All prior experimental work that involved removing the recipient body's head had cut the head off lower down, just below [[Axis (anatomy)|the second bone in the spinal column]]. Ren also used [[Targeted temperature management|moderate hypothermia]] to protect the brains during the procedure.<ref name=Lamba2017rev/>\n\nIn 2016, Ren and Canavero published a review of attempted as well as possible neuroprotection strategies that they said should be researched for potential use in a head transplantation procedure; they discussed various protocols for connecting the vasculature, the use of various levels of hypothermia, the use of [[blood substitutes]], and the possibility of using [[hydrogen sulfide]] as a neuroprotective agent.<ref name=Lamba2017rev/><ref>{{cite journal|last1=Ren|first1=X|last2=Orlova|first2=EV|last3=Maevsky|first3=EI|last4=Bonicalzi|first4=V|last5=Canavero|first5=S|title=Brain protection during cephalosomatic anastomosis.|journal=Surgery|date=July 2016|volume=160|issue=1|pages=5\u201310|doi=10.1016/j.surg.2016.01.026|pmid=27143608}}</ref>"}},
{"article_title": "Business intelligence", "pageid": "168387", "revid": "1062537256", "timestamp": "2021-12-29T02:07:54Z", "history_paths": [["Business intelligence --- Introduction ---", "History"]], "categories": ["business intelligence", "financial data analysis", "data management", "financial technology", "information management"], "heading_tree": {"Business intelligence --- Introduction ---": {"History": {}, "Definition": {"Compared with competitive intelligence": {}, "Compared with business analytics": {}}, "Data": {"Unstructured data vs. semi-structured data": {}, "Limitations of semi-structured and unstructured data": {}, "Metadata": {}}, "Applications": {}, "Roles": {}, "Risk": {}, "See also": {}, "References": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Business intelligence --- Introduction ---|History": "The earliest known use of the term ''business intelligence'' is in Richard Millar Devens' ''Cyclop\u00e6dia of Commercial and Business Anecdotes'' (1865). Devens used the term to describe how the banker [[Sir Henry Furnese, 1st Baronet|Sir Henry Furnese]] gained profit by receiving and acting upon information about his environment, prior to his competitors:\n{{quote|Throughout Holland, Flanders, France, and Germany, he maintained a complete and perfect train of business intelligence. The news of the many battles fought was thus received first by him, and the [[Siege of Namur (1695)|fall of Namur]] added to his profits, owing to his early receipt of the news.|author=Devens |source=p. 210}}\n\nThe ability to collect and react accordingly based on the information retrieved, Devens says, is central to business intelligence.<ref name="Miller Devens">{{cite book|last=Miller Devens|first=Richard|title=Cyclopaedia of Commercial and Business Anecdotes; Comprising Interesting Reminiscences and Facts, Remarkable Traits and Humors of Merchants, Traders, Bankers Etc. in All Ages and Countries|url=https://archive.org/details/cyclopaediacomm00devegoog|quote=business intelligence.|publisher=D. Appleton and company|access-date=15 February 2014|page=[https://archive.org/details/cyclopaediacomm00devegoog/page/n262 210]|year=1865}}</ref>\n\nWhen [[Hans Peter Luhn]], a researcher at [[IBM]], used the term ''business intelligence'' in an article published in 1958, he employed the ''[[Webster's Dictionary]]'' definition of intelligence: "the ability to apprehend the interrelationships of presented facts in such a way as to guide action towards a desired goal."<ref>\n{{cite journal|url= http://www.research.ibm.com/journal/rd/024/ibmrd0204H.pdf|doi=10.1147/rd.24.0314|title= A Business Intelligence System|author=H P Luhn |author-link= Hans Peter Luhn |year= 1958 |journal=  IBM Journal of Research and Development|volume= 2|issue= 4|pages= 314\u2013319|archive-url=https://web.archive.org/web/20080913121526/http://www.research.ibm.com/journal/rd/024/ibmrd0204H.pdf|archive-date=2008-09-13}}\n</ref> \n\nIn 1989, Howard Dresner (later a [[Gartner]] analyst) proposed ''business intelligence'' as an [[umbrella term]] to describe "concepts and methods to improve business decision making by using fact-based support systems."<ref name=power>{{cite web |url= http://dssresources.com/history/dsshistory.html |title= A Brief History of Decision Support Systems, version 4.0 |access-date=10 July 2008 |author= D. J. Power |date= 10 March 2007|publisher= DSSResources.COM }}</ref> It was not until the late 1990s that this usage was widespread.<ref>{{cite web |url=http://dssresources.com/history/dsshistory.html |title=A Brief History of Decision Support Systems |last=Power |first=D. J. |access-date=1 November 2010 }}</ref>\n\nCritics{{who|date=August 2018}} see BI merely as an evolution of [[business reporting]] together with the advent of increasingly powerful and easy-to-use [[data analysis]] tools. In this respect it has also been criticized{{by whom|date=August 2018}} as a marketing buzzword in the context of the "[[big data]]" surge.<ref>{{cite web|title=Decoding big data buzzwords|year=2015|quote=BI refers to the approaches, tools, mechanisms that organizations can use to keep a finger on the pulse of their businesses. Also referred by unsexy versions -- "dashboarding", "MIS" or "reporting".|publisher=cio.com|url=http://www.cio.com/article/2919082/big-data/what-are-they-talking-about-decoding-big-data-buzzwords.html}}</ref>"}},
{"article_title": "Cryopump", "pageid": "169169", "revid": "1058712763", "timestamp": "2021-12-05T04:02:53Z", "history_paths": [["Cryopump --- Introduction ---", "History"]], "categories": ["vacuum pumps", "gases", "gas technologies"], "heading_tree": {"Cryopump --- Introduction ---": {"History": {}, "Operation": {"Regeneration": {}}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cryopump --- Introduction ---|History": "Early experiments into cryotrapping of gasses in [[Activated carbon|activated charcoal]] were conducted as far back as 1874.<ref>{{cite journal | last=Tait | first=P. G. | last2=Dewar | first2=James |author-link2=James Dewar| title=4. Preliminary Note "On a New Method of obtaining very perfect Vacua. | journal=Proceedings of the Royal Society of Edinburgh | publisher=Cambridge University Press (CUP) | volume=8 | year=1875 | issn=0370-1646 | doi=10.1017/s0370164600029734 | pages=348\u2013349}}</ref>\n\nThe first cryopumps mainly used [[liquid helium]] to cool the pump, either in a large liquid helium reservoir, or by continuous flow into the cryopump. However, over time most cryopumps were redesigned to use gaseous helium,<ref>{{cite journal | last=Baechler | first=Werner G. | title=Cryopumps for research and industry | journal=Vacuum | publisher=Elsevier BV | volume=37 | issue=1-2 | year=1987 | issn=0042-207X | doi=10.1016/0042-207x(87)90078-9 | pages=21\u201329}}</ref> enabled by the invention of better [[cryocooler]]s. The key refrigeration technology was discovered in the 1950s by two employees of the Massachusetts-based company [[Arthur D. Little|Arthur D. Little Inc.]], William E. Gifford and [[Howard O. McMahon]]. This technology came to be known as the [[Cryocooler#GM-refrigerators|Gifford-McMahon cryocooler]]. In the 1970s, the Gifford-McMahon cryocooler was used to make a vacuum pump by Helix Technology Corporation and its subsidiary company Cryogenic Technology Inc. In 1976, cryopumps began to be used in [[IBM]]'s manufacturing of integrated circuits.<ref>{{cite journal | last=Bridwell | first=M. C. | last2=Rodes | first2=J. G. | title=History of the modern cryopump | journal=Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films | publisher=American Vacuum Society | volume=3 | issue=3 | year=1985 | issn=0734-2101 | doi=10.1116/1.573017 | pages=472\u2013475}}</ref> The use of cryopumps became common in semiconductor manufacturing worldwide, with expansions such as a cryogenics company founded jointly by Helix and ULVAC ([[jp:\u30a2\u30eb\u30d0\u30c3\u30af]]) in 1981."}},
{"article_title": "UFO conspiracy theories", "pageid": "170479", "revid": "1063101897", "timestamp": "2022-01-01T06:18:01Z", "history_paths": [["UFO conspiracy theories --- Introduction ---", "Background"], ["UFO conspiracy theories --- Introduction ---", "Chronology of UFO conspiracy theories"]], "categories": ["science and technology-related conspiracy theories", "unidentified flying objects", "ufology"], "heading_tree": {"UFO conspiracy theories --- Introduction ---": {"Background": {"Foo fighters": {}, "Ghost rockets": {}, "Flying discs and flying saucers": {}, "Major UFO incidents of 1948": {}}, "Chronology of UFO conspiracy theories": {"1949": {"Winchell and the Soviets": {}, "Keyhoe and the Air Force coverup": {}, "Project Sign": {}, "Scully and alien bodies": {}}, "1950s": {"Carl Allen and the Philadelphia Experiment": {}, "Gray Barker and the 'Men in Black'": {}}, "1960s": {"Vallee and the \"Pentacle Memorandum\"": {}}, "1970s": {"Holloman Air Force Base": {}, "Paul Bennewitz": {}}, "1980s": {"Roswell Incident": {}, "Gordon Cooper": {}, "MJ-12": {}, "Linda Moulton Howe": {}, "George C. Andrews and Milton William Cooper": {}, "Bob Lazar": {}, "''UFO Cover-Up?: Live!''": {}, "July 1989 MUFON Convention": {}}, "1990s": {}, "2000s": {"MoD secret files": {}, "Disclosure": {}}}, "Allegations of evidence suppression": {}, "In popular fiction": {}, "See also": {}, "Notes and references": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"UFO conspiracy theories --- Introduction ---|Background": "Personnel in the mid 1940s reported unidentified objects under various names.\n [[Foo fighter|Foo Fighters]] refer to sightings that first occurred in November 1944, when pilots flying over [[Western Europe]] by night reported seeing fast-moving round glowing objects following their aircraft. The objects were variously described as fiery, and glowing red, white, or orange. Some pilots described them as resembling Christmas-tree lights and reported that they seemed to toy with the aircraft, making wild turns before simply vanishing. Pilots and aircrew reported that the objects flew together in formation with their aircraft and behaved as if they were under intelligent control, but never displayed hostile behavior. However, they could not be outmaneuvered or shot down. The phenomenon was so widespread that the lights earned a name \u2013 in the European Theater of Operations they were often called "Kraut fireballs", but for the most part called "foo fighters". The military took the sightings seriously, suspecting that the mysterious sightings might be secret German weapons, but further investigation revealed that German and Japanese pilots had reported similar sightings.<ref>{{cite book | last = Lucanio | first = Patrick | author2 = Gary Coville | title = Smokin' Rockets: The Romance of Technology in American Film, Radio and Television, 1945\u20131962 | publisher = McFarland | date = 2002 | pages = [https://archive.org/details/smokinrocketsrom00luca/page/16 16\u201317] | url = https://archive.org/details/smokinrocketsrom00luca/page/16 | isbn = 0-7864-1233-X }}</ref>\n\nOn 13 December 1944, the [[Supreme Headquarters Allied Expeditionary Force]] in Paris issued a press release, which was featured in the ''[[The New York Times|New York Times]]'' the next day, officially describing the phenomenon as a "new German weapon".<ref>{{cite news |author=<!--Staff writer(s)/no by-line.--> |title=Floating Mystery Ball Is New Nazi Air Weapon |url=https://www.nytimes.com/1944/12/14/archives/floating-mystery-ball-is-new-nazi-air-weapon.html |work=[[The New York Times]] |date=1944-12-14 |page=6 |access-date=2021-06-12 |archive-date=2021-06-12 |archive-url=https://web.archive.org/web/20210612125052/https://www.nytimes.com/1944/12/14/archives/floating-mystery-ball-is-new-nazi-air-weapon.html |url-status=live }}</ref> Follow-up stories, using the term "Foo Fighters", appeared in the ''[[New York Herald Tribune]]'' and the British ''[[The Daily Telegraph|Daily Telegraph]]''.<ref>{{cite book | last = Hayward | first = James | title = Myths and Legends of the Second World War| publisher = Isis | date = 2003 | pages = 343\u2013344 | isbn = 0-7531-5664-4}}</ref>\n\nIn its 15 January 1945 edition, ''[[Time (magazine)|Time]]'' magazine carried a story entitled "Foo-Fighter", in which it reported that the "balls of fire" had been following [[USAAF]] [[night fighter]]s for over a month, and that the pilots had named it the "foo-fighter". According to ''Time'', descriptions of the phenomena varied, but the pilots agreed that the mysterious lights followed their aircraft closely at high speed.<ref name=time19450115>{{Cite news | title = Foo-Fighter | newspaper = [[Time (magazine)|Time]] | date = 15 Jan 1945 | url = http://www.time.com/time/magazine/article/0,9171,775433,00.html| archive-url = https://web.archive.org/web/20080417042038/http://www.time.com/time/magazine/article/0,9171,775433,00.html| url-status = dead| archive-date = April 17, 2008}}</ref>\n\n {{Main|Ghost rockets}}\nIn 1946 and 1947, numerous reports occurred of so-called [[ghost rockets]] appearing over [[Scandinavia]]n countries, primarily [[Sweden]], which then spread into other European countries.<ref name=GhostR>Ghost Rockets:\n* [[Timothy Good]], ''[[Above Top Secret (book)|Above Top Secret]]'', 1988, William Morrow & Co., {{ISBN|0-688-09202-0}}\n* Timothy Good, ''[[Need to Know: UFOs, the Military, and Intelligence]]'', 2007, Pegasus Books, {{ISBN|978-1-933648-38-5}}\n* [[Donald Keyhoe]], ''[[Aliens From Space]]'', 1973, Doubleday & Co., {{ISBN|0-385-06751-8}}\n* [[Jenny Randles]], ''[[UFO Retrievals: The Recovery of Alien Spacecraft]]'', 1985, Blandford Press, {{ISBN|0-7137-2493-5}}\n* [[Reuben Stone]], ''[[Alien Worlds (book)|Alien Worlds]]'', 1993, Longmeadow Press, {{ISBN|0-681-45414-8}} (Contains photo of search for ghost rocket seen crashing in Lake K\u00f6lmj\u00e4rv)</ref> One USAF top secret document from 1948 stated that [[Swedish Air Force]] Intelligence informed them that some of their investigators felt that the reported objects were not only real but could not be explained as having earthly origins. Similarly, 20 years later, Greek physicist Dr. [[Paul Santorini]] publicly stated that in 1947 he was put in charge of a Greek military investigation into reports of ghost rockets sighted over [[Kingdom of Greece (Gl\u00fccksburg)|Greece]] [ [[Timothy Good]] 1988, p 23; Donald Keyhoe, p 142].<ref name=GhostR/> Again, they quickly concluded the objects were real and not of conventional origin. Santorini claimed their investigation was killed by U.S. scientists and high military officials who had already concluded the objects were extraterrestrial in origin and feared public panic because no defense existed.<ref name=ghost>[[ghost rockets#External links|Ghost Rockets: list of External links to sources]].</ref>\n\n The [[Kenneth Arnold UFO sighting]]  occurred on June 24, 1947, when private pilot [[Kenneth Arnold]] claimed that he saw a string of nine, shiny [[unidentified flying objects]] flying past [[Mount Rainier]] at speeds that Arnold estimated at a minimum of 1,200 miles an hour (1,932 km/hr). This was the first post-[[World War II]] sighting in the United States that garnered nationwide news coverage and is credited with being the first of the modern era of [[UFO sightings]], including numerous reported sightings over the next two to three weeks. Arnold's description of the objects also led to the press quickly coining the terms ''[[flying saucer]]'' and ''flying disc'' as popular descriptive terms for UFOs.  In the weeks that followed Arnold's June 1947 story, at least several hundred reports of similar sightings flooded in from the U.S. and around the world\u2014most of which described saucer-shaped objects.<ref name="Correll">Correll, John T. (June 1, 2011) "[https://www.airforcemag.com/article/0611ufo/ USAF and the UFOs] {{Webarchive|url=https://web.archive.org/web/20211030074457/https://www.airforcemag.com/article/0611ufo/ |date=2021-10-30 }}''. Air Force Magazine. Retrieved October 30, 2021.</ref> A sighting by a United Airlines crew of another nine disk-like objects over Idaho on July 4 probably garnered more newspaper coverage than Arnold's original sighting and opened the floodgates of media coverage in the days to follow.\n\n {{Main|Mantell UFO incident|Gorman dogfight|Chiles-Whitted UFO encounter}}\nOn January 7, 1948, Captain Thomas  Mantell, a [[Kentucky Air National Guard]] pilot, died in the crash of his  fighter near [[Franklin, Kentucky|Franklin]], [[Kentucky]] after being sent in pursuit of an [[unidentified flying object]] (UFO). The event was among the most publicized early UFO incidents.\n\nThe [[Chiles-Whitted UFO encounter]] occurred in the early hours of July 24, 1948, in the skies near [[Montgomery, Alabama|Montgomery]], [[Alabama]].<ref name="Peebles 22">Peebles, p. 22</ref> Two commercial pilots, Clarence Chiles and John Whitted, claimed to have observed a "glowing object" pass by their plane before it appeared to pull up into a cloud and travel out of sight.<ref name="Peebles 22-23">Peebles, pp. 22\u201323</ref>\n\nThe [[Gorman dogfight]] was a widely publicized [[UFO]] incident which took place on October 1, 1948, in the skies over [[Fargo, North Dakota|Fargo]], [[North Dakota]].  [[United States Air Force]] (USAF) Captain [[Edward J. Ruppelt]] wrote in his bestselling and influential ''The Report on Unidentified Flying Objects'' that the "[[dogfight]]" was one of three "classic" UFO incidents in 1948 that "proved to [Air Force] intelligence specialists that UFOs were real," along with the [[Chiles-Whitted UFO encounter]] and the [[Mantell UFO incident]].<ref name="ruppelt30">Ruppelt, p. 30</ref> However, in 1949 the USAF concluded that the Gorman dogfight had been caused by a lighted [[weather balloon]].<ref name=ruppelt31>Ruppelt, p. 31</ref>", "UFO conspiracy theories --- Introduction ---|Chronology of UFO conspiracy theories": "On April 3, 1949, radio personality [[Walter Winchell]] broadcast the claim that it had been definitively established that the flying saucers were guided missiles fired from Russia.<ref name="Jacobs"/>  <ref>{{Cite web|url=http://www.newspapers.com/image/183260308/|title=5 Apr 1949, Page 6 - Star Tribune at Newspapers.com|website=Newspapers.com|access-date=25 December 2021|archive-date=24 December 2021|archive-url=https://web.archive.org/web/20211224002354/https://www.newspapers.com/image/183260308/|url-status=live}}</ref><ref>{{Cite web|url=http://www.newspapers.com/image/553670478/|title=7 Apr 1949, 2 - The Florence Herald at Newspapers.com|website=Newspapers.com|access-date=25 December 2021|archive-date=24 December 2021|archive-url=https://web.archive.org/web/20211224004602/https://www.newspapers.com/image/553670478/|url-status=live}}</ref>  In response, the Air Force denied any such conclusion.<ref>{{Cite news|url=https://www.newspapers.com/clip/2219741/1949-walter-winchell-flying-saucers-from/|title=1949 Walter Winchell Flying Saucers from Russia Air Force denial Long Beach independent CA April 8|newspaper=Independent|date=8 April 1949|page=1|access-date=4 May 2021|archive-date=25 December 2021|archive-url=https://web.archive.org/web/20211225144040/https://www.newspapers.com/clip/2219741/1949-walter-winchell-flying-saucers/|url-status=live}}</ref><ref name="Jacobs">{{Cite book|url = https://books.google.com/books?id=UD5-AAAAMAAJ|title = UFOs and Abductions: Challenging the Borders of Knowledge|isbn = 9780700610327|last1 = Jacobs|first1 = David Michael|year = 2000|access-date = 2021-05-04|archive-date = 2021-05-04|archive-url = https://web.archive.org/web/20210504041911/https://books.google.com/books?id=UD5-AAAAMAAJ|url-status = live}}</ref>   The Air Force reportedly requested an FBI investigation into Winchell's claims, a request that was denied.<ref>{{Cite web|url=https://books.google.com/books?id=74beCQAAQBAJ&pg=PA348|title=The FBI Encyclopedia|first=Michael|last=Newton|date=June 8, 2015|publisher=McFarland|via=Google Books|access-date=December 24, 2021|archive-date=December 25, 2021|archive-url=https://web.archive.org/web/20211225143805/https://books.google.com/books?id=74beCQAAQBAJ&pg=PA348|url-status=live}}</ref>\n\n {{wikisource|The Flying Saucers are Real|"The Flying Saucers are Real" (1949) by Donald Keyhoe}}\nOn December 26, 1949,   ''True'' magazine published an article by [[Donald Keyhoe]] titled [[The Flying Saucers Are Real|"The Flying Saucers Are Real"]].<ref name="Gulyas20210"/>   Keyhoe, a former Major in the US Marines, claimed that elements within the Air Force knew that saucers existed and had concluded they were likely 'inter-planetary'.<ref name="Gulyas20210">{{Cite web|url=https://books.google.com/books?id=a_hPEAAAQBAJ|title=Conspiracy and Triumph: Theories of a Victorious Future for the Faithful|first=Aaron John|last=Gulyas|date=November 8, 2021|publisher=McFarland|via=Google Books|access-date=December 23, 2021|archive-date=December 23, 2021|archive-url=https://web.archive.org/web/20211223072307/https://books.google.com/books?id=a_hPEAAAQBAJ|url-status=live}}</ref>  \n\nThe article  examined the [[Mantell UFO incident]] and quoted an unnamed pilot who opined that the Air Force's explanation "looks like a cover up to me".  The [[Gorman Dogfight]] and the [[Chiles-Whitted UFO encounter]] were also described. The article cited a supposed report from Air Material Command and claimed a "rocket authority at Wright field" had concluded saucers were interplanetary.  Concern over a public panic, of the kind that supposedly occurred after the [[The War of the Worlds (1938 radio drama)|1938 War of the Worlds broadcast]], is cited in the article as a possible motive for the cover up. Citing historic sources, Keyhoe speculated that similar sightings have likely occurred for at least several centuries.\n\nThe ''True'' article caused a sensation.<ref name="Peebles">{{Cite web|url=https://books.google.com/books/about/Watch_the_Skies.html?id=zjI4X7ZOvOIC|title=Watch the Skies!: A Chronicle of the Flying Saucer Myth|first=Curtis|last=Peebles|date=December 25, 1995|publisher=Berkley Books|via=Google Books|access-date=December 23, 2021|archive-date=December 23, 2021|archive-url=https://web.archive.org/web/20211223074720/https://books.google.com/books/about/Watch_the_Skies.html?id=zjI4X7ZOvOIC|url-status=live}}</ref> Though such figures are always difficult to verify, [[Captain (U.S. Air Force)|Captain]] [[Edward J. Ruppelt]], the first head of [[Project Blue Book]], reported that "It is rumored among magazine publishers that Don Keyhoe's article in ''True'' was one of the most widely read and widely discussed magazine articles in history."  When Keyhoe expanded the article into a book, ''The Flying Saucers Are Real'' (1950), it sold over half a million copies in paperback.\n  \nIn March 1950, the Air Force denied "flying saucers" exist and further denied that they were US technology being covered-up.<ref name="Peebles"/>  <ref>{{Cite web|url=http://www.newspapers.com/image/321202817/|title=19 Mar 1950, 1 - The Tribune at Newspapers.com|website=Newspapers.com|access-date=25 December 2021|archive-date=20 December 2021|archive-url=https://web.archive.org/web/20211220032735/https://www.newspapers.com/image/321202817/|url-status=live}}</ref><ref>"The spokesman categorically denied that the Air Force was denying the existence of flying saucers to cover up some of its own experiments in space ships and similar air machines."</ref><!--\n\n[[Donald Keyhoe]] later began investigating flying saucers for ''[[True (magazine)|True]]'' magazine. Keyhoe was one of the first significant conspiracy theorists, asserting eventually that the saucers were from outer space and were on some sort of scouting mission. Keyhoe claimed to derive his theory from his contacts in Air Force and Navy intelligence.  Keyhoe later founded [[NICAP]], a civilian investigation group that asserted the U.S. government was lying about UFOs and covering up information that should be shared with the public. NICAP had many influential board members, including [[Roscoe H. Hillenkoetter]], the first director of the [[CIA]]. To date no [[Scientific evidence|substantiating evidence]] for NICAP's assertions has been presented beyond accounts that are anecdotal and documented hear-say or rumor.<ref name=csicop/>\n\n[[Donald Keyhoe]] was a retired [[United States Marines|U.S. Marine]] who wrote a series of popular books and magazine articles that were very influential in shaping public opinion, arguing that UFOs were indeed real and that the U.S. government was suppressing UFO evidence. Keyhoe's first article on the subject came out in ''[[True (magazine)|True]]'' magazine, January 1950, and was a national sensation. His first book, ''Flying Saucers Are Real'' also came out in 1950, about the same time as Frank Scully's book, and was a bestseller. In 1956, Keyhoe helped establish [[NICAP]], a powerful civilian UFO investigating group with many inside sources. Keyhoe became its director and continued his attacks on the Air Force. Other contemporary critics also charged that the [[United States Air Force]] was perpetrating a [[cover-up]] with its [[Project Blue Book]].\nOn January 22, 1958, when [[Donald Keyhoe]] appeared on CBS television, his statements on UFOs were censored by the Air Force. During the show when Keyhoe tried to depart from the censored script to "reveal something that has never been disclosed before", CBS cut the sound, later stating Keyhoe was about to violate "predetermined security standards" and about to say something he wasn't "authorized to release". What Keyhoe was about to reveal were four publicly unknown military studies concluding UFOs were interplanetary including the 1948 [[Project Sign]] Estimate of the Situation and a 1952 Project Blue Book engineering analysis of UFO motion presented at the [[Robertson Panel]].<ref>{{cite book |last1=Dolan |first1=Richard M. |title=UFOS and the national security state : chronology of a cover-up 1941\u20131973 |year=2002 |publisher=Hampton Roads Pub. Co |isbn=978-1571743176 |pages=[https://archive.org/details/ufosnationalsecu00dola/page/293 293-295] |url=https://archive.org/details/ufosnationalsecu00dola/page/293 }}</ref>\n\n[[Project Sign]], based at Air Technical Intelligence Command at [[Wright-Patterson Air Force Base]] and its successors [[Project Grudge]] and [[Project Blue Book]] were officially assigned to investigate the flying saucers. [[Edward Ruppelt]]'s 1956 book ''The Report on Unidentified Flying Objects'',<ref>''[http://www.nicap.org/rufo\u201301.htm The Report on Unidentified Flying Objects]'', [[Doubleday Books]]</ref> reports that many people within these research groups did in fact support the hypothesis that the flying saucers were from outer space.  According to U.S. Air Force Captain [[Edward J. Ruppelt]],<ref name=Ruppelt>[http://www.nicap.org/rufo/contents.htm Ruppelt: Roswell UFO Cover]</ref> the Air Force's files often mentioned the panicked aftermath of the 1938 ''War of the Worlds'' broadcast as a possible reaction of the public to confirmed evidence of UFOs; however, the files have not been made available to corroborate his assertions.\n--><!-- ====The Great Los Angeles Air Raid====\n{{Main|Battle of Los Angeles}}\n"The Great Los Angeles Air Raid" also known as "The Battle of Los Angeles" is the name given by contemporary sources to the imaginary enemy attack and subsequent anti-aircraft artillery barrage which took place from late February 24 to early February 25, 1942 over [[Los Angeles, California|Los Angeles]], [[California]].<ref name="Caughy">{{cite book|last1=Caughey|first1= John |last2=Caughey|first2=LaRee |title=Los Angeles: biography of a city |url=https://archive.org/details/losangelesbiogra00caug|url-access=registration|page=[https://archive.org/details/losangelesbiogra00caug/page/364 364]|quote=great los angeles air raid.|year=1977|publisher=University of California Press|isbn=978-0-520-03410-5}}</ref><ref name="Farley">{{cite book|last=Farley|first=John E. |title=Earthquake fears, predictions, and preparations in mid-America  |url=https://books.google.com/books?id=N_pf4YBuu9wC&q=%22great+los+angeles+air+raid%22&pg=PA14|access-date=May 17, 2010|year=1998|publisher=Southern Illinois University Press|isbn=978-0-8093-2201-5}}</ref>\n\nInitially, the target of the aerial barrage was thought to be an attacking force from [[Empire of Japan|Japan]], but [[Secretary of the Navy]] [[Frank Knox]] speaking at a press conference shortly afterward called the incident a "false alarm." A small number of modern-day [[UFOlogist]]s have suggested the reported targets were [[extraterrestrial life|extraterrestrial]] spacecraft.<ref name="Robertson2016a">{{cite book|author=David G. Robertson|title=UFOs, Conspiracy Theories and the New Age: Millennial Conspiracism|url=https://books.google.com/books?id=vXgwCwAAQBAJ&pg=PA58|date=25 February 2016|publisher=Bloomsbury Publishing|isbn=978-1-4742-5321-5|pages=58\u2013}}</ref>\n\nWhen documenting the incident in 1983, the U.S. Office of Air Force History attributed the event to a case of "war nerves" likely triggered by a lost [[weather balloon]] and exacerbated by stray flares and shell bursts from adjoining batteries.<ref>[http://www.sfmuseum.org/hist9/aaf2.html San Francisco virtual museum article]</ref>\n--><!--\n {{Main|Project Sign}}\nThe U.S. Air Force may have planted the seeds of UFO conspiracy theories with [[Project Sign]] (established 1947) (which became [[Project Grudge]] and [[Project Blue Book]]). [[Edward J. Ruppelt]], the first director of Blue Book, characterized the Air Force's public behavior regarding UFOs as "[[schizophrenic]]": alternately open and transparent, then secretive and dismissive. Ruppelt also revealed that in mid-1948, Project Sign issued a top secret Estimate of the Situation concluding that the flying saucers were not only real but probably extraterrestrial in origin. According to Ruppelt, the Estimate was ordered destroyed by Air Force Chief of Staff [[Hoyt Vandenberg]].<ref name=Ruppelt>[http://www.nicap.org/rufo/contents.htm Ruppelt: Roswell UFO Cover]</ref>\n\nProject Sign's final report, published in early 1949, stated that while some UFOs appeared to represent actual aircraft, data were insufficient to determine their origin.<ref name=Blum1990>Blum, Howard, Out There: The Government's Secret Quest for Extraterrestrials. Simon and Schuster, 1990</ref>\n--><!--====Interplanetary Phenomenon Unit====\nSome UFOlogists have claimed the existence of a U.S. government group called the "Interplanetary Phenomenon Unit" allegedly established by [[General Douglas MacArthur]] that was "supposedly formed to investigate crashed and retrieved flying saucers".<ref name="Spignesi2000">Stephen J. Spignesi. ''[https://books.google.com/books?id=BRHoKVTawnMC&pg=PA24 The Ufo Book of Lists]''. Citadel Press; 2000. {{ISBN|978-0-8065-2109-1}}. p. 24\u2013.</ref>-->\n\n {{main|Aztec, New Mexico UFO hoax}}\nIn October and November 1949, journalist [[Frank Scully]] published two columns in ''Variety'', claiming that dead [[Extraterrestrial life|extraterrestrial]] beings were recovered from a [[flying saucer]] crash, based on what he said was reported to him by a scientist involved.<ref name="variety1">{{cite news|last=Scully|first=Frank|title=One Flying Saucer Lands In New Mexico|newspaper=Variety|date=12 October 1949|location=New York}}</ref><ref name="variety2">{{cite news|last=Scully|first=Frank|title=Flying Saucers Dismantled, Secrets May Be Lost|newspaper=Variety|date=23 November 1949|location=New York}}</ref><ref>{{Cite web|url=http://archive.org/details/variety176-1949-11|title=Variety (November 1949)|date=December 25, 1949|publisher=New York, NY: Variety Publishing Company|via=Internet Archive}}</ref> His 1950 book ''Behind the Flying Saucers'' expanded on the theme, adding that there had been two such incidents in [[Arizona]] and one in [[New Mexico]], a 1948 incident that involved a saucer that was nearly {{convert|100|ft|m|0}} in diameter.<ref group="note">{{convert|99.99|ft|m|5}} to be exact.</ref> <ref name="reece-34">{{cite book |last=Reece |first=Gregory L. |title=UFO Religion: Inside Flying Saucer Cults and Culture |publisher=[[I. B. Tauris]] |location=London; New York |date=2007 |page=34 |isbn=978-1-845-11451-0}}</ref>\n\nIt was later revealed that Scully had been the victim of "two veteran [[con artist|confidence artists]]".<ref>[http://www.physics.smu.edu/~pseudo/UFOs/Scully/Cahn1.pdf J. P. Cahn expos\u00e9, ''True Magazine'', 1952] {{Webarchive|url=https://web.archive.org/web/20130330161411/http://www.physics.smu.edu/~pseudo/UFOs/Scully/Cahn1.pdf |date=2013-03-30 }}.</ref>\nIn 1952 and 1956, ''[[True (magazine)|True]]'' magazine published articles by ''[[San Francisco Chronicle]]'' reporter John Philip Cahn<ref name="Cahn1">{{cite news |title=The Flying Saucers and the Mysterious Little Men |last=Cahn |first=J.P. |url=http://www.physics.smu.edu/~pseudo/UFOs/Scully/Cahn1.pdf |work=[[True (magazine)|True]] |date=September 1952 |pages=17\u201319, 102\u2013112 |accessdate=29 March 2013 |archive-date=30 March 2013 |archive-url=https://web.archive.org/web/20130330161411/http://www.physics.smu.edu/~pseudo/UFOs/Scully/Cahn1.pdf |url-status=live }}</ref><ref name="Cahn2">{{cite news |title=Flying Saucer Swindlers |last=Cahn |first=J.P. |url=http://www.physics.smu.edu/pseudo/UFOs/Scully/Cahn2.pdf |work=True |date=August 1956 |pages=36\u201337, 69\u201372 |accessdate=30 March 2013 |archive-date=14 May 2013 |archive-url=https://web.archive.org/web/20130514181115/http://www.physics.smu.edu/pseudo/UFOs/Scully/Cahn2.pdf |url-status=live }}</ref> that purported to expose Newton and "Dr. Gee" (identified as Leo A. GeBauer) as oil [[confidence trick|con artists]] who had [[hoax]]ed Scully.<ref>{{cite book|last1=Bartholomew|first1=Robert E.|last2=Howard|first2=George S.|title=UFOs & Alien Contact: Two Centuries of Mystery|date=1998|publisher=[[Prometheus Books]]|location=Amherst, NY|isbn=978-1-573-92200-5|page=[https://archive.org/details/ufosaliencontact00bart/page/193 193]|url-access=registration|url=https://archive.org/details/ufosaliencontact00bart/page/193}}</ref>\n\n The 1950s saw an increase in both governmental and civilian investigative efforts and reports of public [[disinformation]] and suppression of evidence.\n\nThe UK [[Ministry of Defence (United Kingdom)|Ministry of Defence]]'s UFO Project has its roots in a study commissioned in 1950 by the MOD's then Chief Scientific Adviser, the great radar scientist Sir [[Henry Tizard]]. As a result of his insistence that UFO sightings should not be dismissed without some form of proper scientific study, the Department set up the [[Flying Saucer Working Party]] (or FSWP).<ref>[http://www.nickpope.net/ufos_an_official_history.htm Nick Pope, ''UFOs: An Official History''] {{Webarchive|url=https://web.archive.org/web/20130920012510/http://www.nickpope.net/ufos_an_official_history.htm |date=2013-09-20 }}.</ref>\n\nIn August 1950, Montanan baseball manager [[The Mariana UFO Incident|Nicholas Mariana]] filmed several UFOs with his color 16mm camera. [[Project Blue Book]] was called in and, after inspecting the film, Mariana claimed it was returned to him with critical footage removed, clearly showing the objects as disc-shaped. The [[The Mariana UFO Incident|incident]] sparked nationwide media attention.\n\nCanadian radio engineer Wilbert B. Smith, who worked for the Canadian Department of Transport, was interested in flying saucer propulsion technology and wondered if the assertions in the just-published Scully and Keyhoe books were factual. In September 1950, he had the Canadian embassy in Washington D.C. arrange contact with U.S. officials to try to discover the truth of the matter. Smith was briefed by Dr. Robert Sarbacher, a physicist and consultant to the Defense Department's Research and Development Board. Other correspondence, having to do with Keyhoe needing to get clearance to publish another article on Smith's theories of UFO propulsion, indicated that [[Vannevar Bush|Bush]] and his group were operating out of the [[Vannevar Bush#National Science Foundation|Research and Development Board]].<ref>{{Cite web|url=http://www.roswellproof.com/smith_papers.html|title=Wilbert Smith UFO papers|website=www.roswellproof.com|access-date=2009-03-21|archive-date=2009-04-03|archive-url=https://web.archive.org/web/20090403185326/http://www.roswellproof.com/Smith_papers.html|url-status=live}}</ref> Smith then briefed superiors in the Canadian government, leading to the establishment of [[Project Magnet (UFO)|Project Magnet]], a small Canadian government UFO research effort. Canadian documents and Smith's private papers were uncovered in the late 1970s, and by 1984, other alleged documents emerged claiming the existence of a highly secret UFO oversight committee of scientists and military people called [[Majestic 12]], again naming Vannevar Bush. Sarbacher was also interviewed in the 1980s and corroborated the information in Smith's memos and correspondence. Throughout the 1950s and early 1960s, Smith granted public interviews, and among other things stated that he had been lent crashed UFO material for analysis by a highly secret U.S. government group which he wouldn't name.<ref>{{Cite web |url=http://www.roswellproof.com/debris8_misc.html#anchor_3697 |archiveurl=https://web.archive.org/web/20090408085039/http://presidentialufo.com/hardware.htm|url-status=dead |title=Roswell flower tape|archivedate=April 8, 2009 |website=www.roswellproof.com}}</ref>\n\nA few weeks after the [[Robertson Panel]], the Air Force issued Regulation 200-2, ordering air base officers to publicly discuss UFO incidents only if they were judged to have been solved, and to classify all the unsolved cases to keep them out of the public eye. In addition, UFO investigative duties started to be taken on by the newly formed 4602nd Air Intelligence Squadron (AISS) of the [[Air Defense Command]]. The 4602nd AISS was tasked with investigating only the most important UFO cases having intelligence or national security implications. These were deliberately siphoned away from Blue Book, leaving Blue Book to deal with the more trivial reports.<ref>{{cite book |last1=Dolan |first1=Richard M. |title=UFOS and the national security state : chronology of a cover-up 1941\u20131973 |year=2002 |publisher=Hampton Roads Pub. Co |isbn=978-1571743176 |pages=[https://archive.org/details/ufosnationalsecu00dola/page/210 210-211] |url=https://archive.org/details/ufosnationalsecu00dola/page/210 }}</ref>\n\n {{main|Philadelphia Experiment}}\nIn 1955, [[Morris K. Jessup]] achieved some notoriety with his  book ''The Case for the UFO'', in which he argued that [[unidentified flying object]]s (UFOs) represented a mysterious subject worthy of further study. Jessup speculated that UFOs were "exploratory craft of 'solid' and 'nebulous' character."<ref>David Richie, ''UFO: The Definitive Guide to Unidentified Flying Objects and Related Phenomena'', (New York: Facts on File, 1994), p. 116.</ref> Jessup also "linked ancient monuments with prehistoric superscience".<ref>Clark, p. 210.</ref>\n\nIn January 1956, Jessup began receiving a series  of letters to from  "Carlos Miguel Allende", later identified as [[Carl Meredith Allen]].<ref name="NHHC 1996">{{cite web |url=https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/p/philadelphia-experiment/philadelphia-experiment-onr-info-sheet.html |title=Philadelphia Experiment: Office of Naval Research Information Sheet |website=[[Naval History and Heritage Command]] |date=1996-09-08 |access-date=2021-07-11 |url-status=live |archive-url=https://web.archive.org/web/20210514055617/https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/p/philadelphia-experiment/philadelphia-experiment-onr-info-sheet.html |archive-date=2021-05-14}}</ref><ref name="Allen 1956">{{cite web |author-last=Allen |author-first=Carl M. |date=1956 |title=The Carl Allen Letters |website=The Philadelphia Experiment From A\u2013Z |url=https://www.de173.com/carl-allen/ |access-date=2021-07-18 |archive-url=https://web.archive.org/web/20160808142934/http://www.de173.com/carl-allen/ |archive-date=2016-08-08 |url-status=live }}</ref><ref name="Hochheimer">{{cite web |author-last=Hochheimer |author-first=Andrew H. |title=Carlos Miguel Allende or Carl Meredith Allen or... |website=The Philadelphia Experiment From A\u2013Z |url=https://www.de173.com/carlos-miguel-allende-carl-allen/ |access-date=2021-07-10 |url-status=live |archive-url=https://web.archive.org/web/20200520103422/https://www.de173.com/carlos-miguel-allende-carl-allen/ |archive-date=2020-05-20}}</ref> The first known letter warned Jessup not to investigate the levitation of UFOs, and subsequent letters put forward a story of dangerous 1943 science experiment at the [[Philadelphia Naval Shipyard]].  According to the account, a ship was successfully made invisible, but the ship inexplicably teleported to [[Norfolk, Virginia]] for several minutes and then reappeared in the Philadelphia yard.  The ship's crew was supposed to have suffered various side effects, including insanity, intangibility, and being "frozen" in place.<ref name="Allen 1956"/> \n\nIn 1957,<ref name="Moore 1990">{{cite book |author-last=Moore |author-first=William L. |author-link=Bill Moore (ufologist) |others=in consultation with [[Charles Berlitz|Berlitz, Charles]] |title=The Philadelphia Experiment: Project Invisibility |location=New York |publisher=Fawcett Crest; Ballantine |date=1990 |orig-date=1979 |url=https://archive.org/details/philadelphiaexp000moor/ |url-access=registration |access-date=2021-07-18 }}</ref>{{rp|67}} Jessup was invited to the Office of Naval Research where he was shown an annotated copy of his book that was filled with handwritten notes in its margins, written with three different shades of blue ink, appearing to detail a debate among three individuals. They discussed ideas about the propulsion for [[flying saucers]], [[extraterrestrial intelligence|alien races]], and express concern that Jessup was too close to discovering their technology.<ref name="Jessup 2003">{{cite book |title=The Case for the UFO: Unidentified Flying Objects |version="Varo Edition" |author-last=Jessup |author-first=Morris K. |author-link=Morris K. Jessup |date=2003 |orig-date=1955 |location=Castelnau-Barbarens, France |publisher=Quantum Future Group  |url=https://archive.org/details/THECASEFORTHEUFOVaroEditionM.K.Jessup/ |access-date=2021-07-18 |via=The [[Internet Archive]]}}</ref>{{rp|27-29, 35, 65, 80, 102, 115, 163-165}}  Jessup noticed the handwriting of the annotations resembled the letters he received from Allen.<ref name="Varo 2003">{{cite book |title=The Case for the UFO: Unidentified Flying Objects |version="Varo Edition" |author-last=Jessup |author-first=Morris K. |author-link=Morris K. Jessup |date=2003 |orig-date=1955 |location=Castelnau-Barbarens, France |publisher=Quantum Future Group |contribution=Introduction |pages=8-10 |contributor=Varo Manufacturing Company |url=https://archive.org/details/THECASEFORTHEUFOVaroEditionM.K.Jessup/ |access-date=2021-07-18 |via=The [[Internet Archive]]}}</ref>{{rp|9}}  (Twelve years later, Allen would say that he authored all of the annotations in order \u201cto scare the hell out of Jessup.\u201d)<ref name="APRO 1969">{{cite periodical |work=The A.P.R.O. Bulletin |publisher=[[Aerial Phenomena Research Organization]] |date=July-August 1969 |location=Tuscon, Arizona |title=Allende Letters a Hoax |url=https://www.de173.com/allende-letters-a-hoax/ |pages=1,3 |url-status=live |access-date=2021-07-18 |archive-url=https://web.archive.org/web/20210718234027/https://www.de173.com/allende-letters-a-hoax/ |archive-date=2021-07-18 |via=The Philadelphia Experiment From A\u2013Z}}</ref>\n\nThe Jessup book with Allen's scribbled commentaries gained a life of its own when the Varo Manufacturing Corporation of Garland, Texas, who did contract work for ONR, began producing [[mimeograph]]ed copies of the book with Allen's annotations and Allen's letters to Jessup.<ref name="Varo 2003"/>{{rp|9}}  These copies came to be known as the "Varo edition."<ref>{{cite magazine |author-last=Steiger |author-first=Brad |title=The Mysterious Allende Letters |pages=4-9 |magazine=The Allende Letters\n|url=https://www.yumpu.com/en/document/view/56302830/the-allende-letters-1968 |access-date=2021-07-18 |publisher=Universal Publishing |location=New York |date=1968}}</ref>{{rp|6}} This became the heart of many "Philadelphia Experiment" books, documentaries, and movies to come. Over the years various writers and researchers who tried to get more information from Carl Allen found his responses elusive, or could not find him at all.<ref>[https://windmill-slayer.tripod.com/aliascarlosallende/ Robert A. Goerman, Alias Carlos Allende, FATE, October 1980]</ref>\n\n {{main|Men in Black}}\n1956 saw the publication of [[Gray Barker]]'s ''They Knew Too Much About Flying Saucers'', the book which publicized the idea of [[Men in black|Men in Black]] who appear to UFO witnesses and warn them to keep quiet. There has been continued speculation that the men in black are government agents who harass and threaten UFO witnesses.\n\nAccording to the ''[[Skeptical Inquirer]]'' article "Gray Barker: My Friend, the Myth-Maker", there may have been "a grain of truth" to Barker's writings on the Men in Black, in that the [[United States Air Force]] and other government agencies did attempt to discourage public interest in UFOs during the 1950s. However, Barker is thought to have greatly embellished the facts of the situation. In the same ''Skeptical Inquirer'' article, Sherwood revealed that, in the late 1960s, he and Barker collaborated on a brief fictional notice alluding to the Men in Black, which was published as fact first in [[Raymond A. Palmer]]'s ''[[Flying Saucers (magazine)|Flying Saucers]]'' magazine and some of Barker's own publications. In the story, Sherwood (writing as "Dr. Richard H. Pratt") claimed he was ordered to silence by the "blackmen" after learning that UFOs were time-travelling vehicles. Barker later wrote to Sherwood, "Evidently the fans swallowed this one with a gulp."<ref>John C. Sherwood. [http://www.csicop.org/si/show/gray_barker_my_friend_the_myth-maker/ "Gray Barker: My Friend, the Myth-Maker"] {{Webarchive|url=https://web.archive.org/web/20110512004941/http://www.csicop.org/si/show/gray_barker_my_friend_the_myth-maker/ |date=2011-05-12 }}. ''[[Skeptical Inquirer]]''. May/June 1998. Retrieved on June 19, 2008.</ref>\n\n \nThroughout much of the 1960s, atmospheric physicist [[James E. McDonald]] suggested\u2014via lectures, articles and letters\u2014that the U.S. Government was mishandling evidence that would support the [[extraterrestrial hypothesis]].<ref>''see'' James E. McDonald: [[James E. McDonald#External links|External links]].</ref> {{better source needed|date=December 2021}}\n\n In June 1967, researcher [[Jacques Vallee]] was tasked with organizing files collected by [[Project Bluebook]] investigator [[J. Allen Hynek]]<ref name="Forbidden">Jacque Vallee, Forbidden Science</ref><ref>The Phenomenon (2020)</ref>  Among those files, Vallee found a memo dated 9 January 1953 addressed an assistant of [[Edward J. Ruppelt]], an Air Force officer assigned to Bluebook.<ref name="Forbidden"/>   The memo was signed "H.C. Cross", but Vallee elected to refer to the author under the pseudonym "Pentacle".<ref name="Forbidden"/>\n\nThe memo referred to a previously-unknown analysis of several thousand UFO reports, along with calls for agreements about "what can and what cannot be discussed" with the 1953 Roberson Panel.<ref name="Forbidden"/>   Writing in his 1967 journal, Vallee expressed the opinion that the memo, if it were published, "would cause an even bigger uproar among foreign scientists than among Americans: it would prove the devious nature of the statements made by the Pentagon all these years about the non-existence of UFOs".<ref name="Forbidden"/>\n\n [[Jerome Clark]] comments that many UFO conspiracy theory tales "can be traced to a mock documentary ''[[Alternative 3]]'', broadcast on British television on June 20, 1977 (but intended for [[April Fools' Day]]), and subsequently turned into a paperback book."<ref>Clark ''The UFO Book'', p. 213\u201314</ref>\n\n \nClark cites a 1973 encounter as perhaps the earliest suggestion that the U.S. government was involved with ETs. That year, Robert Emenegger and Allan Sandler of [[Los Angeles, California]] were in contact with officials at [[Norton Air Force Base]] in order to make a [[documentary film]]. Emenegger and Sandler report that Air Force Officials (including [[Paul Shartle]]) suggested incorporating UFO information in the documentary, including as its centerpiece genuine footage of a 1971 UFO landing at [[Holloman Air Force Base]] in [[New Mexico]]. Furthermore, says Emenegger, he was given a tour of Holloman AFB and was shown where officials conferred with [[Extraterrestrial life|Extraterrestrial Biological Entities (EBEs)]]. This was supposedly not the first time the U.S. had met these aliens, as Emenegger reported that his U.S. military sources had "been monitoring signals from an alien group with which they were unfamiliar, and did their ET guests know anything about them? The ETs said no" <ref>Clark ''The UFO Book'', p. 144</ref> The documentary was released in 1974 as ''[[UFOs: Past, Present, and Future]]'' (narrated by [[Rod Serling]]) containing only a few seconds of the Holloman UFO footage, the remainder of the landing depicted with illustrations and re-enactments.\n\nIn 1988, Shartle said that the film in question was genuine, and that he had seen it several times.\n\nIn 1976 a televised documentary report ''[[UFOs: It Has Begun]]''<ref>''UFOS: It Has Begun'', Producer [[Allan F. Sandler]], Director [[Ray Rivas]], Writer [[Robert Emenegger]], 1976, Featuring [[Rod Serling]], Special Appearances by [[Jos\u00e9 Ferrer]] and [[Burgess Meredith]] \u2013 VCI Sci-Fi DVD Double Feature: ''UFOs: It Has Begun / UFO Syndrome'', Distributed by [[VCI Entertainment]]  http://www.vcient.com {{Webarchive|url=https://web.archive.org/web/20190910181455/http://www.vcient.com/ |date=2019-09-10 }}</ref> written by Robert Emenegger was presented by Rod Serling, [[Burgess Meredith]] and [[Jos\u00e9 Ferrer]]. Some sequences were recreated based upon the statements of eyewitness observers, together with the findings and conclusions of governmental civil and military investigations. The documentary uses a hypothetical UFO landing at Holloman AFB as a backdrop.\n\n \nThe late 1970s also saw the beginning of controversy centered on [[Paul Bennewitz]] of [[Albuquerque, New Mexico]].<ref>''see'' Paul Bennewitz: [[Paul Bennewitz#Further reading|References and External Links]].</ref> {{better source needed|date=December 2021}}\n\n  {{Main|Roswell Incident}}\nIn 1947, the [[United States Air Force]] issued a press release stating that a "flying disk" had been [[Roswell incident|recovered]] near [[Roswell, New Mexico]]. This press release was quickly withdrawn, and officials stated that a [[weather balloon]] had been misidentified. The Roswell case quickly faded even from the attention of most [[ufology|UFOlogists]] until the 1970s. Speculation persisted despite the official denial that an alien spacecraft crashed near Roswell.\n\nIn the 1990s, the US military published two reports disclosing the true nature of the crashed aircraft: a surveillance balloon from Project Mogul. Nevertheless, the Roswell incident continues to be of interest to the media, and conspiracy theories surrounding the event persist. Roswell has been described as "the world's most famous, most exhaustively investigated and most thoroughly debunked UFO claim".<ref>{{cite journal |title=A Roswell requiem |first=B.D. |last=Gildenberg |journal=Skeptic |volume=10 |issue=1 |year=2003 |page=60}}</ref>\n\n By 1981,<ref>https://books.google.com/books?id=H_BO36JhUSMC</ref>{{better|date=December 2021}} astronaut [[Gordon Cooper]] reported suppression of a flying saucer movie filmed in high clarity by two [[Edwards AFB]] range photographers on May 3, 1957. Cooper said he viewed developed negatives of the object, clearly showing a dish-like object with a dome on top and something like holes or ports in the dome. When later interviewed by [[James E. McDonald|James McDonald]], the photographers and another witness confirmed the story. Cooper said military authorities then picked up the film and neither he nor the photographers ever heard what happened to it. The incident was also reported in a few newspapers, such as the ''[[Los Angeles Times]]''. The official explanation was that the photographers had filmed a weather balloon distorted by hot desert air.<ref>{{cite web|url=http://www.ufoevidence.org/Newsite/Files/MacDonaldSubmissionUFOSymposium.pdf|title=McDonald, 1968 Congressional testimony, Case 41|url-status=dead|archive-url=https://web.archive.org/web/20060624204634/http://www.ufoevidence.org/Newsite/Files/MacDonaldSubmissionUFOSymposium.pdf|archive-date=2006-06-24}}</ref>{{better|date=December 2021}}\n\n \nThe so-called [[Majestic 12]] documents surfaced in 1982, suggesting that there was secret, high-level U.S. government interest in UFOs dating to the 1940s. Upon examination, the [[Federal Bureau of Investigation]] (FBI) declared the documents to be "completely bogus", and many ufologists consider them to be an elaborate [[hoax]].<ref name="Donovan2011b">{{cite book|last=Donovan|first=Barna William|title=Conspiracy Films: A Tour of Dark Places in the American Conscious|url=https://books.google.com/books?id=bJkhqU1IXHAC&pg=PA107|access-date=17 September 2014|date=2011-07-20|publisher=McFarland|isbn=9780786486151|pages=107\u2013|archive-date=2016-10-05|archive-url=https://web.archive.org/web/20161005205106/https://books.google.com/books?id=bJkhqU1IXHAC&pg=PA107|url-status=live}}</ref><ref>{{cite web |url=http://vault.fbi.gov/Majestic%2012/Majestic%2012%20Part%201%20of%201/at_download/file |title=FBI \u2013 Majestic 12 Part 1 of 1 |work=An FBI archive containing details of "Majestic 12" |access-date=April 10, 2011 |archive-date=January 31, 2021 |archive-url=https://web.archive.org/web/20210131044307/https://vault.fbi.gov/Majestic%2012/Majestic%2012%20Part%201%20of%201/at_download/file |url-status=live }}</ref>\n\n [[Linda Moulton Howe]] is an advocate of [[conspiracy theory|conspiracy theories]] that [[cattle mutilations]] are of [[extraterrestrial life|extraterrestrial]] origin and speculations that the U.S. government is involved with aliens.<ref name="Knight2003">{{cite book|author=Peter Knight|title=Conspiracy Theories in American History: An Encyclopedia|url=https://books.google.com/books?id=qMIDrggs8TsC&pg=PA125|access-date=18 October 2012|year=2003|publisher=ABC-CLIO|isbn=978-1-57607-812-9|pages=125\u2013|archive-date=26 June 2014|archive-url=https://web.archive.org/web/20140626225811/http://books.google.com/books?id=qMIDrggs8TsC&pg=PA125|url-status=live}}</ref><ref name="Barkun2006">{{cite book|author=Michael Barkun|title=A Culture of Conspiracy: Apocalyptic Visions in Contemporary America|url=https://books.google.com/books?id=LiwjVsNBw-cC&pg=PA86|access-date=18 October 2012|date=4 May 2006|publisher=University of California Press|isbn=978-0-520-24812-0|pages=86\u2013|archive-date=26 June 2014|archive-url=https://web.archive.org/web/20140626225656/http://books.google.com/books?id=LiwjVsNBw-cC&pg=PA86|url-status=live}}</ref><ref name="Editor1998">{{cite book|author=Nancy Lusignan, Editor|title=Fear Itself: Enemies Real and Imagined in American Culture|url=https://books.google.com/books?id=dkYyuNvfqY8C&pg=PA415|access-date=18 October 2012|date=1 September 1998|publisher=Purdue University Press|isbn=978-1-55753-115-5|pages=415\u2013|archive-date=26 June 2014|archive-url=https://web.archive.org/web/20140626225756/http://books.google.com/books?id=dkYyuNvfqY8C&pg=PA415|url-status=live}}</ref><ref name="Landes2000">{{cite book|author=Richard Landes|title=Encyclopedia of Millennialism and Millennial Movements|url=https://books.google.com/books?id=4eVZaI20_mEC&pg=PA731|access-date=18 October 2012|date=6 July 2000|publisher=Taylor & Francis|isbn=978-0-415-92246-3|pages=731\u2013|archive-date=26 June 2014|archive-url=https://web.archive.org/web/20140626225719/http://books.google.com/books?id=4eVZaI20_mEC&pg=PA731|url-status=live}}</ref>\n\n In 1986, conspiracy theorist George C. Andrews authored ''Extra-Terrestrials Among Us'', accusing the CIA of the Kennedy assassination.<ref name="barkun">{{Cite book|url=https://books.google.com/books?id=-0wFZRWKdfoC&pg=PA88|title=A Culture of Conspiracy: Apocalyptic Visions in Contemporary America|first1=Michael|last1=Barkun|pages=87\u201399,137\u201338,147|date=November 7, 2003|publisher=University of California Press|isbn=9780520238053|via=Google Books|access-date=December 13, 2021|archive-date=December 9, 2021|archive-url=https://web.archive.org/web/20211209234028/https://books.google.com/books?id=-0wFZRWKdfoC&pg=PA88|url-status=live}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=bRnpjmamWsYC|title=Extra-terrestrials Among Us|first=George Clinton|last=Andrews|date=December 10, 1986|publisher=Llewellyn Publications|isbn=9780875420103|via=Google Books|access-date=December 13, 2021|archive-date=December 10, 2021|archive-url=https://web.archive.org/web/20211210004757/https://books.google.com/books?id=bRnpjmamWsYC|url-status=live}}</ref>    Citing Andrews as a source, in 1991 the UFO conspiracy author [[Milton William Cooper|Bill Cooper]] published the influential conspiracy work ''Behold a Pale Horse'' which claimed that Kennedy was killed after he "informed [[Majestic 12]] that he intended to reveal the presence of aliens to the American people".<ref>{{Cite book|url=https://books.google.com/books?id=Z8e5YELGGFAC|title=Enemies Within: The Culture of Conspiracy in Modern America|first=Robert Alan|last=Goldberg|date=October 1, 2008|publisher=Yale University Press|isbn=978-0300132946|via=Google Books|access-date=December 13, 2021|archive-date=December 9, 2021|archive-url=https://web.archive.org/web/20211209063741/https://books.google.com/books?id=Z8e5YELGGFAC|url-status=live}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=g0aen3LDErAC|title=Behold a Pale Horse|first=William|last=Cooper|date=April 11, 2012|publisher=Light Technology Publishing|isbn=9781622335022|via=Google Books|access-date=December 13, 2021|archive-date=December 9, 2021|archive-url=https://web.archive.org/web/20211209063745/https://books.google.com/books?id=g0aen3LDErAC|url-status=live}}</ref>  ''Behold a Pale Horse'' became 'wildly popular' with conspiracy theorists and went on to be one of the most-read books in the US prison system.<ref>{{Cite news|url=https://www.nytimes.com/2018/09/02/books/pale-horse-rider-william-cooper-mark-jacobson-interview.html|title=Tell Us 5 Things About Your Book: A Godfather of Conspiracy Thinking|first=John|last=Williams|newspaper=The New York Times|date=September 2, 2018|access-date=December 13, 2021|archive-date=December 10, 2021|archive-url=https://web.archive.org/web/20211210013841/https://www.nytimes.com/2018/09/02/books/pale-horse-rider-william-cooper-mark-jacobson-interview.html|url-status=live}}</ref> According to [[Michael Barkun]],  the theories of Andrews and Cooper helped create "a conspiracist form of UFO speculation, which [[Jerome Clark]] refers to as ufology's 'dark side'."<ref name="barkun"/>\n\n \nIn November 1989, [[Bob Lazar]] appeared in a special interview with investigative reporter George Knapp on Las Vegas TV station KLAS to discuss his alleged employment at S-4.<ref>[http://www.8newsnow.com/story/3369879/bob-lazar-the-man-behind-area-51 KLAS-TV: 8 News Now: George Knapp, Investigative Reporter: "Bob Lazar The Man Behind Area 51: NEW: Area 51 Exposed] {{Webarchive|url=https://web.archive.org/web/20150223132918/http://www.8newsnow.com/story/3369879/bob-lazar-the-man-behind-area-51 |date=2015-02-23 }} retrieved 21 March 2013</ref> In his interview with Knapp, Lazar said he first thought the saucers were secret, terrestrial aircraft, whose test flights must have been responsible for many UFO reports. Gradually, on closer examination and from having been shown multiple briefing documents, Lazar came to the conclusion that the discs must have been of extraterrestrial origin. He claims that they use [[moscovium]], an element that decays in a fraction of a second, to warp space, and that "Grey" aliens are from the [[Zeta Reticuli]] star system. According to the ''[[Los Angeles Times]],'' he never obtained the degrees he claims to hold from MIT and Caltech.<ref>''[[Los Angeles Times]]'': May 6, 1993, [[Ray Rivenberg|Rivenberg, Ray]], "Unusually Fanatical Observers Ike Struck Deal With Aliens!"</ref><ref>[http://www.presidentialufo.com/articles-a-papers/379-the-true-story-of-area-51-a-look-at-the-actual-evidence The Presidents UFO Website: ''The True Story of Area 51: A Look at the Actual Evidence''] {{Webarchive|url=https://web.archive.org/web/20130111183913/http://www.presidentialufo.com/articles-a-papers/379-the-true-story-of-area-51-a-look-at-the-actual-evidence |date=2013-01-11 }}, Written by [[Grant Cameron]], Monday, 03 October 2011 18:29 retrieved 21 March 2013</ref>\n\n \nOn October 14, 1988, actor [[Mike Farrell]] hosted ''U.S. UFO Cover-Up: Live!'', a two-hour television special "focusing on the government's handling of information regarding UFOs" and "whether there has been any suppression of evidence supporting the existence of UFOs".<ref name="TCM">{{cite web|title=UFO Cover-Up?... Live (1988|url=http://www.tcm.com/tcmdb/title/475950/UFO-Cover-Up-Live/|website=[[Turner Classic Movies]]|publisher=Turner Classic Movies, Inc.|access-date=29 November 2017|archive-date=1 December 2017|archive-url=https://web.archive.org/web/20171201034912/http://www.tcm.com/tcmdb/title/475950/UFO-Cover-Up-Live/|url-status=live}}</ref>\n\n \nThe [[Mutual UFO Network]] held their 1989 annual convention in [[Las Vegas, Nevada]], on July 1, 1989.\n\nThe Ufologist [[Bill Moore (ufologist)|Bill Moore]] was scheduled as the main speaker, and he refused to submit his paper for review prior to the convention, and also announced that he would not answer any follow-up questions as was common practice. Unlike most of the convention's attendees, Moore did not stay at the same hotel that was hosting the convention.\n\nWhen he spoke, Moore said that he and others had been part of an elaborate, long-term [[disinformation]] campaign begun primarily to discredit [[Paul Bennewitz]]: "My role in the affair ... was primarily that of a freelancer providing information on Paul's (Bennewitz) current thinking and activities".<ref name="Clark163">Clark ''The UFO Book'', p. 163</ref> Air Force Sergeant Richard C. Doty was also involved, said Moore, though Moore thought Doty was "simply a pawn in a much larger game, as was I."<ref name="Clark163" /> One of their goals, Moore said, was to disseminate information and watch as it was passed from person to person in order to study information channels.\n\nMoore said that he "was in a rather unique position" in the disinformation campaign: "judging by the positions of the people I knew to be directly involved in it, [the disinformation] definitely had something to do with national security. There was no way I was going to allow the opportunity to pass me by ... I would play the disinformation game, get my hands dirty just often enough to lead those directing the process into believing I was doing what they wanted me to do, and all the while continuing to burrow my way into the matrix so as to learn as much as possible about who was directing it and why."<ref>Clark ''The UFO Book'', p. 164</ref> Once he finished the speech, Moore immediately left the hotel and Las Vegas that same night.\n\nMoore's claims sent shock waves through the small, tight-knit UFO community{{citation needed|date=January 2020}}, which remains divided as to the reliability of his assertions.\n\n \nOn November 24, 1992, a UFO reportedly crashed in Southaven Park, [[Shirley, New York]].<ref>[http://www.ufocasebook.com/southavenufo.html UFO Crash At Southaven Park<!-- bot-generated title -->] {{Webarchive|url=https://web.archive.org/web/20060809194302/http://ufocasebook.com/southavenufo.html |date=2006-08-09 }} at www.ufocasebook.com</ref>  John Ford, a Long Island [[Mutual UFO Network|MUFON]] researcher, investigated the crash. Four years later, on June 12, 1996, Ford was arrested and charged with plotting to poison several local politicians by sneaking [[radium]] in their toothpaste. On advice of counsel Ford pleaded insanity and was committed to the Mid Hudson Psychiatric Center. Critics say the charges are a [[frame-up]].\n\nThe [[Branton Files]] have circulated on the internet at least since the mid-1990s. They essentially recirculate the information presented above, with many asides from "[[Bruce Alan Walton|Branton]]", the document's editor.\n\nPhilip Schneider of the [[patriot movement]], an engineer and geologist formerly working for the U.S. government, made a few appearances at UFO conventions in the 1990s, espousing essentially a new version of the theories mentioned above. He claimed to have played a role in the construction of Deep Underground Military Bases (DUMBs) across the United States, and as a result he said that he had been exposed to classified information of various sorts as well as having personal experiences with EBEs. He claimed to have survived the [[Dulce Base]] catastrophe and decided to tell his tale.<ref>{{cite web|title=The Phil Schneider Story|url=http://www.apfn.org/apfn/phil.htm|publisher=APFN|access-date=26 April 2013|archive-date=27 April 2013|archive-url=https://web.archive.org/web/20130427122518/http://www.apfn.org/apfn/PHIL.HTM|url-status=dead}}</ref> He died by suicide on January 17, 1996, after a series of lectures given in late 1995 on topics including the [[Black Budget]] and underground alien bases. Others believe that Schneider did not take his own life and that he was actually murdered by the government.<ref>{{Cite web|url=http://www.apfn.org/apfn/ex_wifephil.htm|title=Message from ex-wife of Phil Schneider|website=www.apfn.org|access-date=2017-12-16|archive-date=2017-12-01|archive-url=https://web.archive.org/web/20171201062222/http://www.apfn.org/apfn/ex_wifephil.htm|url-status=dead}}</ref>\n\n 2003 saw the publication of ''Alien Encounters'' ({{ISBN|1-57821-205-7}}), by [[Chuck Missler]] and Mark Eastman, which primarily re-stated the notions presented above (especially Cooper's) and presents them as fact. {{cn|date=December 2021}}\n\n Eight files from 1978 to 1987 on UFO sightings were first released on May 14, 2008, to the National Archives' website by the British Ministry of Defence. Two hundred files were set to be made public by 2012. The files are correspondence from the public sent to government officials, such as the MoD and [[Margaret Thatcher]]. The information can be downloaded.<ref>[http://www.nationalarchives.gov.uk/ufos UFO files from The National Archives<!-- bot-generated title -->] {{Webarchive|url=https://web.archive.org/web/20080728231520/http://www.nationalarchives.gov.uk/ufos/ |date=2008-07-28 }} at www.nationalarchives.gov.uk</ref> Copies of Lt. Col. Halt's letter regarding the sighting at RAF Woodbridge (see above{{where|date=October 2016}}) to the U.K. Ministry of Defence were routinely released (without additional comment) by the USA's base public affairs staff throughout the 1980s until the base closed. The MoD released the files due to requests under the [[Freedom of Information Act 2000|Freedom of Information Act]].<ref>{{cite news\n|title=Files released on UFO sightings\n|date=2008-05-14\n|work=[[BBC News]]\n|url=http://news.bbc.co.uk/2/hi/uk_news/7398108.stm\n|access-date=2008-08-05\n|archive-date=2008-07-20\n|archive-url=https://web.archive.org/web/20080720115509/http://news.bbc.co.uk/2/hi/uk_news/7398108.stm\n|url-status=live\n}}</ref> The files included reports of "lights in the sky" from Britons.<ref>{{Cite web |url=http://afp.google.com/article/ALeqM5j0OnawpQKsmDXbJAce-OI5EiUgHQ |archiveurl=https://web.archive.org/web/20130605221509/http://afp.google.com/article/ALeqM5j0OnawpQKsmDXbJAce-OI5EiUgHQ |url-status=dead |title=afp.google.com, The truth is out there: Britons 'spotted' UFOs, records say|archivedate=June 5, 2013}}</ref>\n\n In the early 2000s, the concept of "disclosure" became increasingly popular in the UFO conspiracy community: that the government had classified and withheld information on alien contact and full disclosure was needed, and was pursued by activist lobbying groups.\n\nIn 1993, [[Steven M. Greer]] founded the Disclosure Project to promote the concept. In May 2001, Greer held a press conference at the [[National Press Club (United States)|National Press Club]] in [[Washington, D.C.|D.C]] that demanded Congress hold hearings on "secret U.S. involvement with UFOs and extraterrestrials".<ref name="washtimes">{{cite news|title=Government is covering up UFO evidence, group says |first=Julia |last=Duin |url=http://www.washtimes.com/national/20010510-19816390.htm |newspaper=[[The Washington Times]] |date=11 May 2001 |access-date=8 March 2013 |url-status=dead |archive-url=https://web.archive.org/web/20010516132431/http://www.washtimes.com/national/20010510-19816390.htm |archive-date=May 16, 2001 }}</ref><ref name="Daily Record">{{cite news | title=They're Here; UFO watchers to reveal proof that aliens have visited Earth | newspaper=The Daily Record | date=May 9, 2001 | url=https://www.questia.com/read/1G1-74321804 | access-date=January 7, 2019 | archive-date=July 23, 2020 | archive-url=https://web.archive.org/web/20200723225147/https://www.questia.com/read/1G1-74321804/they-re-here-ufo-watchers-to-reveal-proof-that-aliens | url-status=live }}</ref><ref name="abcnews">{{cite news\n |title = Group Calls for Disclosure of UFO Info\n |author = Katelynn Raymer\n |author2 = David Ruppe\n |url = https://abcnews.go.com/Technology/story?id=98572\n |newspaper = [[ABC News]]\n |date = 10 May 2001\n |access-date = 11 March 2013\n |archive-date = 28 July 2013\n |archive-url = https://web.archive.org/web/20130728235120/http://abcnews.go.com/Technology/story?id=98572\n |url-status = live\n }}</ref> It was described by an attending BBC reporter as "the strangest ever news conference hosted by Washington's august National Press Club."<ref>{{cite news|url=http://news.bbc.co.uk/2/hi/americas/1322432.stm|title=UFO spotters slam 'US cover-up'|work=[[BBC News]]|date=May 10, 2001|access-date=May 11, 2016|archive-date=July 23, 2019|archive-url=https://web.archive.org/web/20190723074515/http://news.bbc.co.uk/2/hi/americas/1322432.stm|url-status=live}}</ref> The Disclosure Project's claims were met with by derision by [[skepticism|skeptics]] and spokespeople for the [[U. S. Air Force]].<ref>{{cite web | last =Kehnemui | first =Sharon | title =Men in Suits See Aliens as Part of Solution, Not Problem | work =[[Fox News]] | date =May 10, 2001 | url =http://www.foxnews.com/story/0,2933,24364,00.html | access-date =2007-05-10 | archive-date =2013-08-25 | archive-url =https://web.archive.org/web/20130825092411/http://www.foxnews.com/story/0,2933,24364,00.html | url-status =live }}</ref><ref>{{cite magazine | last =McCullagh | first =Declan | author-link =Declan McCullagh | title =Ooo-WEE-ooo Fans Come to D.C. | magazine =Wired News | date =May 10, 2001 | url =http://archive.wired.com/culture/lifestyle/news/2001/05/43526 | access-date =11 May 2016 | archive-date =3 June 2016 | archive-url =https://web.archive.org/web/20160603065714/http://archive.wired.com/culture/lifestyle/news/2001/05/43526 | url-status =live }}</ref>\n\nIn 2013, the production company CHD2, LLC<ref>{{cite news|title=The Citizen Hearing on Disclosure|url=http://www.citizenhearing.org/about-chd|website=Official Citizen Hearing on Disclosure website|access-date=2017-05-11|archive-date=2017-05-15|archive-url=https://web.archive.org/web/20170515211941/http://www.citizenhearing.org/about-chd/|url-status=live}}</ref> held a "Citizen Hearing on Disclosure" at the [[National Press Club (United States)|National Press Club]] in [[Washington, D.C.|D.C]] from 29 April to 3 May 2013. The group paid former U.S. Senator [[Mike Gravel]] and former Representatives [[Carolyn Cheeks Kilpatrick]], [[Roscoe Bartlett]], [[Merrill Cook]], [[Darlene Hooley]], and [[Lynn Woolsey]] $20,000 each to participate, and to preside over panels of academics and former government and military officials discussing UFOs and extraterrestrials.<ref>{{cite news|title=Visitors From Outer Space, Real or Not, Are Focus of Discussion in Washington|url=https://www.nytimes.com/2013/05/04/us/politics/panel-convenes-in-washington-to-discuss-aliens.html|newspaper=[[New York Times]]|date=May 3, 2013|access-date=September 17, 2017|archive-date=August 20, 2017|archive-url=https://web.archive.org/web/20170820192655/http://www.nytimes.com/2013/05/04/us/politics/panel-convenes-in-washington-to-discuss-aliens.html|url-status=live}}</ref>\n\nOther such groups include [[Citizens Against UFO Secrecy]], founded in 1977."}},
{"article_title": "Shock absorber", "pageid": "170829", "revid": "1053848996", "timestamp": "2021-11-06T12:57:01Z", "history_paths": [["Shock absorber --- Introduction ---", "Early history"]], "categories": ["shock absorbers", "motorcycle suspension technology", "automotive suspension technologies", "vehicle safety technologies", "auto parts", "mechanical power control"], "heading_tree": {"Shock absorber --- Introduction ---": {"Description": {"Vehicle suspension": {}}, "Early history": {}, "Types of vehicle shock absorbers": {"Twin-tube": {"Basic twin-tube": {}, "Twin-tube gas charged": {}, "Position sensitive damping": {}, "Acceleration sensitive damping": {}, "Coilover": {}}, "Mono-tube": {}, "Spool valve": {}}, "Theoretical approaches": {}, "Special features": {}, "Shock absorber and strut comparison": {}, "See also": {}, "References": {}, "Sources": {}, "Bibliography": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Shock absorber --- Introduction ---|Early history": "In common with carriages and railway locomotives, most early motor vehicles used [[leaf spring]]s. One of the features of these springs was that the friction between the leaves offered a degree of damping, and in a 1912 review of vehicle suspension, the lack of this characteristic in helical springs was the reason it was "impossible" to use them as main springs.<ref >"Springs - A simple study of car suspension", The Automotor Journal, August 10th, 1912, pp936-937</ref> However the amount of damping provided by leaf spring friction was limited and variable according to the conditions of the springs, and whether wet or dry. It also operated in both directions. Motorcycle front suspension adopted coil sprung Druid forks from about 1906, and similar designs later added [[Friction disk shock absorber|rotary friction dampers]], which damped both ways - but they were adjustable (e.g. 1924 Webb forks). These [[friction disk shock absorber]]s were also fitted to many cars.\n\nOne of the problems with motor cars was the large variation in sprung weight between lightly loaded and fully loaded, especially for the rear springs. When heavily loaded the springs could bottom out, and apart from fitting rubber 'bump stops', there were attempts to use heavy main springs with auxiliary springs to smooth the ride when lightly loaded, which were often called 'shock absorbers'. Realising that the spring and vehicle combination bounced with a characteristic frequency, these auxiliary springs were designed with a different period, but were not a solution to the problem that the spring rebound after striking a bump could throw you out of your seat. What was called for was damping that operated on the rebound.\n\nAlthough C.L. Horock came up with a design in 1901 that had hydraulic damping, it worked in one direction only. It does not seem to have gone into production right away, whereas mechanical dampers such as the Gabriel Snubber started being fitted in the late 1900s (also the similar Stromberg Anti-Shox). These used a belt coiled inside a device such that it freely wound in under the action of a coiled spring, but met friction when drawn out. Gabriel Snubbers were fitted to an 11.9HP [[Arrol-Johnston]] car which broke the 6 hour Class B record at [[Brooklands]] in late 1912, and the Automotor journal noted that this snubber might have a great future for racing due to its light weight and easy fitment.<ref name="AMJ" >"Some accessories to see at Olympia", The Automotor Journal, Nov 2nd , 1912, p1284</ref>\n\nOne of the earliest hydraulic dampers to go into production was the Telesco Shock Absorber, exhibited at the 1912 Olympia Motor Show and marketed by Polyrhoe Carburettors Ltd.<ref name="AMJ" /> This contained a spring inside the telescopic unit like the pure spring type 'shock absorbers' mentioned above, but also oil and an internal valve so that the oil damped in the rebound direction. The Telesco unit was fitted at the rear end of the leaf spring, in place of the rear spring to chassis mount, so that it formed part of the springing system, albeit a hydraulically damped part.<ref >"What a Chauffeur Expects to see at Olympia", The Automotor Journal, Nov 9th 1912, p1313</ref> This layout was presumably selected as it was easy to apply to existing vehicles, but it meant the hydraulic damping was not applied to the action of the main leaf spring, but only to the action of the auxiliary spring in the unit itself.\n\nThe first production hydraulic dampers to act on the main leaf spring movement were probably those based on an original concept by Maurice Houdaille patented in 1908 and 1909. These used a [[lever arm shock absorber|lever arm]] which moved hydraulically damped vanes inside the unit. The main advantage over the friction disk dampers was that it would resist sudden movement but allow slow movement, whereas the rotary friction dampers tended to stick and then offer the same resistance regardless of speed of movement. There appears to have been little progress on commercialising the lever arm shock absorbers until after [[World War I]], after which they came into widespread use, for example as standard equipment on the [[Ford Model A (1927\u201331)|1927 Ford Model A]] and manufactured by [[Ralph Peo#Career|Houde Engineering Corporation]] of Buffalo, NY."}},
{"article_title": "Telecine", "pageid": "170870", "revid": "1057127286", "timestamp": "2021-11-25T16:48:18Z", "history_paths": [["Telecine --- Introduction ---", "History of telecine"]], "categories": ["film and video technology", "television terminology"], "heading_tree": {"Telecine --- Introduction ---": {"History of telecine": {}, "Frame rate differences": {"2:2 pulldown {{anchor|22pulldown}}": {}, "2:3 pulldown {{anchor|23pulldown}}": {}, "Other pulldown patterns": {}, "Telecine judder": {}, "Reverse telecine (a.k.a. inverse telecine (IVTC), reverse pulldown)": {}}, "Telecine hardware": {"Flying spot scanner": {}, "Line array CCD": {}, "Pulsed LED/triggered three CCD camera system": {}, "Digital intermediate systems and virtual telecines": {}, "Video cameras that produce telecined video, and \"film look\"": {}}, "Digital television and high definition": {}, "Gate weave": {}, "Soft and hard telecine": {}, "Image gallery": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Telecine --- Introduction ---|History of telecine": "With the advent of popular [[broadcast television]], producers realized they needed more than [[live television]] programming. By turning to film-originated material, they would have access to the wealth of films made for the cinema in addition to recorded [[television program]]ming on film that could be aired at different times. However, the difference in [[frame rate]]s between film (generally 24 frames/s) and television (30 or 25 frames/s, [[Interlaced video|interlaced]]) meant that simply playing a film into a television camera would result in flickering.\n\nOriginally the [[kinescope]] was used to record the image from a television display to film, synchronized to the TV scan rate. This could then be re-played directly into a video camera for re-display.<ref>Pincus, Edward and Ascher, Steven. (1984). ''The Filmmaker's Handbook''. Plume. p. 368-9 {{ISBN|0-452-25526-0}}</ref> Non-live programming could also be filmed using the same cameras, edited mechanically as normal, and then played back for TV. As the film was run at the same speed as the television, the flickering was eliminated. Various displays, including projectors for these "video rate films", [[slide projector]]s and film cameras were often combined into a "[[film chain]]", allowing the broadcaster to cue up various forms of media and switch between them by moving a mirror or prism. Color was supported by using a multi-tube video camera, prisms, and filters to separate the original color signal and feed the red, green and blue to individual tubes.\n\nHowever, this still left film shot at cinema [[frame rate]]s as a problem. The obvious solution is to simply speed up the film to match the television frame rates, but this, at least in the case of [[NTSC]], is rather obvious to the eye and ear. This problem is not difficult to fix, however; the solution being to periodically play a selected frame twice. For NTSC, the difference in frame rates can be corrected by showing every fourth frame of film twice, although this does require the sound to be handled separately to avoid "skipping" effects. A more advanced technique is to use "2:3 pulldown", discussed below, which turns every second frame of the film into three ''[[field (video)|field]]s'' of video, which results in a slightly smoother display. [[PAL]] uses a similar system, "2:2 pulldown". However, during the analogue broadcasting period, the 24 frame per second film was shown at a slightly faster 25 frames per second rate, to match the PAL video signal. This resulted in a fractionally higher audio soundtrack, and resulted in feature films having a slightly shorter duration, by being shown 1 frame per second faster.\n\nIn recent decades, telecine has primarily been a film-to-storage process, as opposed to film-to-air. Changes since the 1950s have primarily been in terms of equipment and physical formats; the basic concept remains the same. [[Home movies]] originally on film may be transferred to [[video tape]] using this technique, and it is not uncommon to find telecined DVDs where the source was originally recorded on videotape, or shot on film and then edited on tape. Movies and TV shows that were originally shot and edited on film, or digitally, are more commonly put on DVD at their native frame rate with flags that tell the DVD player to perform pulldown on-the-fly."}},
{"article_title": "Magnetoencephalography", "pageid": "172211", "revid": "1046835385", "timestamp": "2021-09-27T17:06:56Z", "history_paths": [["Magnetoencephalography --- Introduction ---", "History"]], "categories": ["magnetoencephalography", "electrodiagnosis", "medical tests", "neurotechnology", "neuroimaging"], "heading_tree": {"Magnetoencephalography --- Introduction ---": {"History": {}, "The basis of the MEG signal": {}, "Magnetic shielding": {"Magnetically shielded room (MSR)": {}, "Active shielding system": {}}, "Source localization": {"The inverse problem": {}, "Magnetic source imaging": {}, "Dipole model source localization": {}, "Distributed source models": {}, "Independent component analysis (ICA)": {}}, "Use in the field": {"Brain connectivity and neural oscillations": {}, "Focal epilepsy": {}, "Fetal": {}}, "Comparison with related techniques": {"MEG in comparison to EEG": {}}, "See also": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Magnetoencephalography --- Introduction ---|History": "[[Image:MIT EarlyYEARS-261 croped.tif|thumbnail|250px|left|Dr. Cohen's shielded room at MIT, in which first MEG was measured with a SQUID]]\n[[Image:MIT EarlyYears-233a.jpg|thumbnail|500px|left|First MEG measured with SQUID, in Dr. Cohen's room at MIT]]\nMEG signals were first measured by University of Illinois physicist [[David Cohen (physicist)|David Cohen]] in 1968,<ref name="cohen1">{{cite journal | vauthors = Cohen D | title = Magnetoencephalography: evidence of magnetic fields produced by alpha-rhythm currents | journal = Science | volume = 161 | issue = 3843 | pages = 784\u20136 | date = August 1968 | pmid = 5663803 | doi = 10.1126/science.161.3843.784 | bibcode = 1968Sci...161..784C | s2cid = 34001253 }}</ref> before the availability of the [[SQUID]], using a copper induction coil as the detector. To reduce the magnetic background noise, the measurements were made in a magnetically shielded room. The coil detector was barely sensitive enough, resulting in poor, noisy MEG measurements that were difficult to use. Later, Cohen built a much better shielded room at MIT, and used one of the first SQUID detectors, just developed by [[James Edward Zimmerman|James E. Zimmerman]], a researcher at Ford Motor Company,<ref>{{cite journal | vauthors = Zimmerman JE, Theine P, Harding JT |title=Design and operation of stable rf-biased superconducting point-contact quantum devices, etc|journal=Journal of Applied Physics|year= 1970|volume=41|issue=4|pages=1572\u20131580|doi=10.1063/1.1659074}}</ref> to again measure MEG signals.<ref>{{cite journal | vauthors = Cohen D | title = Magnetoencephalography: detection of the brain's electrical activity with a superconducting magnetometer | journal = Science | volume = 175 | issue = 4022 | pages = 664\u20136 | date = February 1972 | pmid = 5009769 | doi = 10.1126/science.175.4022.664 | url = http://davidcohen.mit.edu/sites/default/files/documents/1972ScienceV175(SquidMEG).pdf | bibcode = 1972Sci...175..664C | s2cid = 29638065 }}</ref> This time the signals were almost as clear as those of [[Electroencephalography|EEG]]. This stimulated the interest of physicists who had been looking for uses of SQUIDs. Subsequent to this, various types of spontaneous and evoked MEGs began to be measured.\n\nAt first, a single SQUID detector was used to successively measure the magnetic field at a number of points around the subject's head. This was cumbersome, and, in the 1980s, MEG manufacturers began to arrange multiple sensors into arrays to cover a larger area of the head. Present-day MEG arrays are set in a helmet-shaped [[vacuum flask]] that typically contain 300 sensors, covering most of the head.  In this way, MEGs of a subject or patient can now be accumulated rapidly and efficiently.\n\nRecent developments attempt to increase portability of MEG scanners by using [[SERF|spin exchange relaxation-free]] (SERF) magnetometers. SERF magnetometers are relatively small, as they do not require bulky cooling systems to operate. At the same time, they feature sensitivity equivalent to that of SQUIDs. In 2012, it was demonstrated that MEG could work with a chip-scale atomic magnetometer (CSAM, type of SERF).<ref>{{cite journal | vauthors = Sander TH, Preusser J, Mhaskar R, Kitching J, Trahms L, Knappe S | title = Magnetoencephalography with a chip-scale atomic magnetometer | journal = Biomedical Optics Express | volume = 3 | issue = 5 | pages = 981\u201390 | date = May 2012 | pmid = 22567591 | pmc = 3342203 | doi = 10.1364/BOE.3.000981 }}</ref> More recently, in 2017, researchers built a working prototype that uses SERF magnetometers installed into portable individually 3D-printed helmets,<ref name=":0" /> which they noted in interviews could be replaced with something easier to use in future, such as a bike helmet."}},
{"article_title": "Transrapid", "pageid": "172228", "revid": "1061022732", "timestamp": "2021-12-19T04:18:22Z", "history_paths": [["Transrapid --- Introduction ---", "Development history and versions"]], "categories": ["electrodynamics", "emerging technologies", "experimental and prototype high-speed trains", "high-speed trains of germany", "land speed record rail vehicles", "magnetic levitation", "magnetic propulsion devices", "monorails", "siemens products"], "heading_tree": {"Transrapid --- Introduction ---": {"Technology": {"Levitation": {}, "Propulsion": {}, "Energy requirements": {}, "Market segment, ecological impact and historical parallels": {}, "Ecological impact": {}, "Comparative costs": {"Track construction cost": {}, "Train purchase cost": {}, "Operational cost": {}}}, "Implementations": {"China": {}, "Germany": {}}, "Planned systems": {"Iran": {}, "Switzerland": {}, "Colorado I-70": {}, "Los Angeles to Las Vegas": {}, "Other US": {}, "Tenerife": {}}, "Rejected systems": {"Germany": {"High-speed competition": {}, "Munich link": {}}, "United Kingdom": {}}, "Incidents": {"September 2006 accident": {}, "SMT fire accident": {}}, "Alleged theft of Transrapid technology": {}, "Development history and versions": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": true, "history_section_non_designated": false, "history_section_texts": {"Transrapid --- Introduction ---|Development history and versions": "{| class="wikitable"\n|-\n! Date !! Train !! Location !! Present location !! Comments !! Top speed (km/h)\n|-\n|| 1969 / 1970 ? || Transrapid 01 || [[Munich]] || [[Deutsches Museum]], Munich || By [[Krauss-Maffei]]. Indoor benchtop model. Only 600 mm long track. || \n|-\n|| 6 May 1971 || [[Messerschmitt-B\u00f6lkow-Blohm|MBB]] Prinzipfahrzeug || MBB's [[Ottobrunn]] factory (near [[Munich]]), Germany || [[Freilassing Locomotive World]] || By MBB. First passenger-carrying principle vehicle. 660 m test track. ''Prinzipfahrzeug''=principle [demonstrator] vehicle. || 90 (1971)\n|-\n|| 6 October 1971 || Transrapid 02 || [[Krauss-Maffei]]'s plant in [[Munich]] - [[Allach-Untermenzing|Allach]], Germany || [[Krauss-Maffei]], Munich || By Krauss-Maffei. 930 m test track which included one curve. Displayed at Paris Expo from 4 June to 9 June 1973. || 164 (October 1971)\n|-\n|| 16 August 1972 || Transrapid 03 || [[Munich]] || Scrapped || By Krauss-Maffei. [[Ground effect train|Air-cushion vehicle]] (ACV or [[hovercraft]]) propelled by a linear motor. The system was abandoned in 1973 due to the too high noise generation and the too large consumption. Attempts in France ([[A\u00e9rotrain]]) and in the USA ([http://www.shonner.com/aerotrain/]) led in the following years to similar decisions. 930 m test track. || 140 (September 1972)\n|-\n|| 1972 / 1974 ? || Erlangener Erprobungstr\u00e4ger (EET 01) || Southern edge of [[Erlangen]] (near [[Nuremberg]]), Germany || ? || By [[Siemens]] and others. Electrodynamic suspension (EDS) (like [[JR-Maglev]]). Unmanned. 880 m circular track. ''Erlangener Erprobungstr\u00e4ger''=Erlangen test carrier. || 160 / 230 (1974) ?\n|-\n|| 20 December 1973 || Transrapid 04 || Munich - Allach, Germany || [[Technik Museum Speyer]] || By Krauss-Maffei. || 250 (end 1973), 253.2 (21 November 1977)\n|-\n|| 1974 / January 1975 ? || Komponentenme\u00dftr\u00e4ger (KOMET) || [[Manching]], Germany || near Lathen in a barn || By MBB. Unmanned. 1300 m track. || 401.3 (1974)\n|-\n|| 1975 || HMB1 || [[Thyssen-Henschel|Thyssen Henschel]] in [[Kassel]], Germany || ? || By [[Thyssen-Henschel|Thyssen Henschel]]. First functional longstator vehicle. 100 m guideway. Unmanned. ||\n|-\n|| 1976 || HMB2 || Thyssen Henschel in [[Kassel]], Germany || Technik-Museum, [[Kassel]] || By Thyssen Henschel. World's first passenger-carrying, longstator vehicle. 100 m guide-way. || 36 (or 40 ?)\n|-\n|| 17 May 1979 || Transrapid 05 || [[:de:Internationale Verkehrsausstellung|International Transportation Exhibition]] (IVA 79) in [[Hamburg]]. Reassembled in [[Kassel]] in 1980. || Technik-Museum, [[Kassel]] || 908 m track. || 75\n|-\n|| June 1983 || Transrapid 06 || [[Emsland test facility|Transrapid Versuchsanlage Emsland]] (TVE), Germany || A part is in [[Deutsches Museum]] at Bonn, other part in Lathen || Presented to public in [[Munich]] on 13 March 1983. 31.5 km track. || 302 (1984), 355 (1985), 392 (1987), 406 (1987), 412.6 (January 1988)\n|-\n|| 1988 || Transrapid 07 || Transrapid Versuchsanlage Emsland (TVE), Germany || A part is at Max B\u00f6gl KG Sengenthal, other part in Lathen || Presented to public at the International Transportation Exhibition (IVA 88) in Hamburg. || 436 (1989), 450 (17 June 1993)\n|-\n|| August 1999 || Transrapid 08 || Transrapid Versuchsanlage Emsland (TVE), Germany || Destroyed 22 September 2006 in [[2006 Lathen maglev train accident|accident]], remaining parts are stored in Lathen || ||\n|-\n|| 2002 || Transrapid SMT || [[Shanghai Maglev Train]], China || Shanghai, China || || 501 (12 November 2003)\n|-\n|| 2007 || Transrapid 09 || Transrapid Versuchsanlage Emsland (TVE), Germany || Kemper Factory in Nortrup || Offered for sale in October 2016<ref>{{cite web |url= http://www.vebeg.de/web/de/verkauf/suchen.htm?SHOW_AUS=1643270&SHOW_LOS=1&nolistlink=1| title=Magnetschwebebahn "ThyssenKrupp" Transrapid 09 best. aus| language=de| access-date=7 October 2016}}</ref><ref>{{cite web |url= http://www.vebeg.de/images/lospics/70/1643270.001.pdf |title= Tender 1643270 |language= de,en |access-date= 7 Oct 2016 |url-status= dead |archive-url= https://web.archive.org/web/20161009152447/http://www.vebeg.de/images/lospics/70/1643270.001.pdf |archive-date= 2016-10-09 }}</ref>  Five years after the shutdown of the Transrapid pilot plant Emsland in 2011, the Kemper family, the owners of H. Kemper GmbH & Co. KG, purchased the Transrapid 09 for \u20ac 200,001. In September 2017, it was erected on the company premises in Nortrup. The three sections of the train is then  used as conference and exhibition space for the history of the Transrapid. Hermann Kemper, the inventor of the maglev train, came from the same family as the owners of the sausage and meat products manufacturer Kemper.||\n|}"}},
{"article_title": "Music tracker", "pageid": "172428", "revid": "1062078822", "timestamp": "2021-12-26T03:54:42Z", "history_paths": [["Music tracker --- Introduction ---", "History"]], "categories": ["amiga software", "audio trackers", "demoscene", "music software", "video game music technology"], "heading_tree": {"Music tracker --- Introduction ---": {"History": {"1987: origins on the Amiga": {}, "1990s: MS-DOS PC versions": {}, "2000s: Multiple platforms": {}}, "Terminology": {}, "See also": {}, "Further reading": {}, "External links": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Music tracker --- Introduction ---|History": "[[File:schism-beyond.gif|left|thumb|280px|Schism Tracker with a pure [[text mode]] based [[GUI]], playing a module from the video game ''[[Bejeweled 2]]'' by Finnish composer [[Peter Hajba|Skaven]].]]\n{{demoscene}}\n\n \nThe term tracker derives from '''[[Ultimate Soundtracker]]''' (the first tracker software<ref>{{cite book|author1=Olga Guriunova|title=Art Platforms and Cultural Production on the Internet|year=2012|publisher=Routledge|isbn=978-0-415-89310-7|pages=162|url=https://books.google.com/books?id=svTOmgMUGW0C|access-date=2014-09-13}}</ref>) written by Karsten Obarski and released in 1987 by EAS Computer Technik for the [[Commodore Amiga]].<ref>{{cite web | url=http://helllabs.org/tracker-history/ |publisher=helllabs.org |first=Claudio |last=Matsuoka |date=2007-11-04 |access-date=2011-01-29 |title=Tracker History Graphing Project |quote=''[http://helllabs.org/tracker-history/trackers.svg Tracker History Graph]''}}</ref> ''Ultimate Soundtracker'' was a commercial product, but soon [[shareware]] [[Clone (computing)|clones]] such as '''[[NoiseTracker]]''' (1989<ref>{{Cite web|url=https://techworld.idg.se/2.2524/1.586076/noisetracker-fyller-25-ar|title=Noisetracker fyller 25 \u00e5r}}</ref>) appeared as well. The general concept of step-sequencing samples numerically, as used in trackers, is also found in the [[Fairlight CMI]] sampling workstation of the early 1980s. Some early tracker-like programs appeared for the [[MSX]] ([[Yamaha CX5M]]) and [[Commodore 64]], before 1987,  such as '''Sound Monitor''', but these did not feature sample playback, instead playing notes on the computer's internal synthesizer. Later, programs like '''Rock Monitor''' also supported additional sample playback, usually with short drum samples loaded in RAM memory.\n\nThe first trackers supported four pitch and volume modulated channels of 8-bit [[Pulse-code modulation|PCM]] [[sampling (signal processing)|samples]], a limitation derived from the Amiga's [[Original Chip Set#Paula|Paula]] audio chipset and the commonplace [[8SVX]] format used to store sampled sound. However, since the notes were samples, the limitation was less important than those of synthesizing music chips.<ref name="Examples of synthesizing music chips">[[Commodore International|Commodore]]'s [[MOS Technology SID|SID]] or General Instruments' venerable [[AY-3-8912]] and Yamaha's compatible YM2149.</ref>\n\n \nDuring the 1990s, tracker musicians gravitated to the PC as software production in general switched from the Amiga platform to the PC. Although the IBM and compatibles initially lacked the hardware sound processing capabilities of the Amiga, with the advent of the [[Sound Blaster]] line from [[Creative Technology Limited|Creative]], PC audio slowly began to approach [[Compact disc|CD]] Quality ([[44,100 Hz|44.1 kHz/16 bit/Stereo]]) with the release of the [[SoundBlaster 16]].\n\nAnother sound card popular on the PC tracker scene was the [[Gravis Ultrasound]], which continued the hardware mixing tradition, with 32 internal channels and onboard memory for sample storage. For a time, it offered unparalleled sound quality and became the choice of discerning tracker musicians. Understanding that the support of tracker music would benefit sales, Gravis gave away some 6000 GUS cards to participants. Coupled with excellent developer documentation, this gesture quickly prompted the GUS to become an integral component of many tracking programs and software. Inevitably, the balance was largely redressed with the introduction of the [[Sound Blaster AWE32]] and its successors, which also featured on-board RAM and [[Table-lookup synthesis|wavetable]] (or [[Sample-based synthesis|sample]] table) mixing.\n\nThe responsibility for [[Audio mixing (recorded music)|audio mixing]] passed from hardware to software (the main [[CPU]]) which gradually enabled the use of more channels. From the typical 4 MOD channels of the Amiga, the limit had moved to 7 with '''TFMX''' players and 8, first with '''Oktalyzer''' and later with the vastly more popular '''[[OctaMED]]''' (Amiga, 1989), then 32 with '''[[ScreamTracker|ScreamTracker 3]]''' (PC, 1994) and '''[[FastTracker 2]]''' (PC, 1994) and on to 64 with '''[[Impulse Tracker]]''' (PC, 1995) and '''[[OctaMED|MED SoundStudio]]''' (updated version of OctaMED). An Amiga tracker called '''Symphonie Pro''' even supported 256 channels.\n\nAs such, hardware mixing did not last. As processors got faster and acquired special multimedia processing abilities (e.g. [[MMX (instruction set)|MMX]]) and companies began to push [[Hardware Abstraction Layer]]s, like [[DirectX]], the AWE and GUS range became obsolete. [[DirectX]], [[Windows Driver Model|WDM]] and, now more commonly, [[Audio Stream Input/Output|ASIO]], deliver high-quality sampled audio irrespective of hardware brand.\n\nThere was also a split off from the sample based trackers taking advantage of the [[Yamaha YM3812|OPL2]] and [[Yamaha YMF262|OPL3]] chips of the Sound Blaster series. All Sound Tracker was able to combine both the FM synthesis of the OPL chips and the sample based synthesis of the EMU-8000 chips in the Sound Blaster AWE series of cards as well as MIDI output to any additional hardware of choice.\n\n[[Jeskola Buzz]] is a modular music studio developed from 1997-2000 for Microsoft Windows using a tracker as its sequencer where the sounds where produced by virtual machines (''Buzzmachines'') such as signal generators, synthesizer emulators, drum computers, samplers, effects and control machines, that where connected in a modular setup. Each machine would have its own tracker, drum machines would use a tracker-like drum pattern editor and effect and control machines could be automated tracker-like via tables of parameters.\n\n \nTracker music could be found in [[computer game]]s of the late 1990s and early 2000s, such as the [[Unreal (video game series)|''Unreal'' series]], ''[[Deus Ex (video game)|Deus Ex]]'', ''[[Crusader: No Remorse]]'', ''[[Jazz Jackrabbit]]'' and ''[[Uplink (video game)|Uplink]]''. Some of the early Amiga trackers such as '''[[ProTracker]]''' (1990) and OctaMED have received various updates, mostly for porting to other platforms. [[ProTracker]] having resumed development in 2004, with plans for releasing version 5 to Windows and [[AmigaOS]], but only version 4.0 beta 2 for AmigaOS has been released.\n\n[[File:Renoise 2.6.png|thumb|290px|[[Renoise]], a popular tracker in the 2000s and 2010s.]]\nDuring 2007, '''[[Renoise]]''' (PC, 2002) and '''[[OpenMPT]]''' (PC, 1997) were presented in ''[[Computer Music (magazine)|Computer Music Magazine]]'' as professional and inexpensive alternative to other music production software.<ref name=cmm>{{cite journal |journal=Computer Music Magazine |date=June 2007 |title=Top Trackers |issue=113 |publisher=Future Publishing Ltd |url=http://www.musicradar.com/computermusic/computer-music-june-issue-cmu113-on-sale-now-246001 |access-date=11 January 2017 |quote=''Tracker! The amazing free music software giving the big boys a run for their money.''}}</ref>"}},
{"article_title": "Laser cooling", "pageid": "172586", "revid": "1061849794", "timestamp": "2021-12-24T11:14:51Z", "history_paths": [["Laser cooling --- Introduction ---", "History"]], "categories": ["thermodynamics", "atomic physics", "cooling technology", "laser applications"], "heading_tree": {"Laser cooling --- Introduction ---": {"Methods": {}, "History": {"Early attempts": {}, "Modern advancements": {}}, "Doppler cooling": {}, "Anti-Stokes cooling": {}, "Uses": {}, "See also": {}, "References": {}, "Additional sources": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Laser cooling --- Introduction ---|History": "At the advent of laser cooling techniques, Maxwell's theory of [[electromagnetism]] had already led to the quantification of electromagnetic radiation exerting a force ([[radiation pressure]]), however it wasn't until the turn of the twentieth century when studies by [[Pyotr Lebedev|Lebedev]] (1901), [[Ernest Fox Nichols|Nichols]] (1901), and [[Gordon Ferrie Hull|Hull]] (1903) experimentally demonstrated that force.<ref name=":2">{{Cite journal|last=Adams and Riis|first=Charles S. and Erling|title=Laser Cooling and Manipulation of Neutral Particles|url=http://massey.dur.ac.uk/articles/newoptics.pdf|journal=New Optics}}</ref> Following that period, in 1933, [[Otto Frisch|Frisch]] exemplified the pressure exerted on atoms by light. Starting in the early 1970s, [[laser]]s were then utilized to further explore [[atom]] manipulation. The introduction of lasers in atomic manipulation experiments acted as the advent of laser cooling proposals in the mid 1970s. Laser cooling was separately introduced in 1975 by two different research groups: [[Theodor W. H\u00e4nsch|H\u00e4nsch]] and [[Arthur Leonard Schawlow|Schawlow]], and [[David Wineland|Wineland]] and [[Hans Georg Dehmelt|Dehmelt]]. They both outlined a process of slowing heat-based [[velocity]] in atoms by "radiative forces."<ref name=":0">{{Cite journal|last=Phillips|first=William D.|title=Nobel Lecture: Laser cooling and trapping of neutral atoms|journal=Reviews of Modern Physics|volume=70|issue=3|pages=721\u2013741|doi=10.1103/revmodphys.70.721|bibcode=1998RvMP...70..721P|year=1998|doi-access=free}}</ref> In the paper by H\u00e4nsch and Schawlow, the effect of radiation pressure on any object that reflects light is described. That concept was then connected to the cooling of atoms in a gas.<ref>{{cite journal |last1=H\u00e4nsch |first1=T.W. |last2=Schawlow |first2=A.L. |title=Cooling of gases by laser radiation |journal=Optics Communications |date=January 1975 |volume=13 |issue=1 |pages=68\u201369 |doi=10.1016/0030-4018(75)90159-5 |bibcode=1975OptCo..13...68H |doi-access=free }}</ref>  These early proposals for laser cooling only relied on "scattering force", the name for the radiation pressure. In later proposals, ''laser trapping'', a variant of cooling which requires both scattering and a [[dipole]] force, would be introduced.<ref name=":0" />\n\nIn the late 70s, [[Arthur Ashkin|Ashkin]] described how radiation forces can be used to both optically trap atoms and simultaneously cool them.<ref name=":2" /> He emphasized how this process could allow for long [[Spectroscopy|spectroscopic]] measurements without the atoms escaping the trap and proposed the overlapping of [[Optics|optical]] traps in order to study interactions between different atoms.<ref>{{Cite journal|last=Ashkin|first=A.|title=Trapping of Atoms by Resonance Radiation Pressure|journal=Physical Review Letters|volume=40|issue=12|pages=729\u2013732|doi=10.1103/physrevlett.40.729|bibcode=1978PhRvL..40..729A|year=1978|doi-access=free}}</ref> Closely following Ashkin's letter in 1978, two research groups: Wineland, Drullinger and Walls, and Neuhauser, Hohenstatt, Toscheck and Dehmelt further refined that work.<ref name=":0" /> In specific, Wineland, Drullinger, and Walls were concerned with the improvement of spectroscopy. The group wrote about experimentally demonstrating the cooling of atoms through a process using radiation pressure. They cite a precedence for using radiation pressure in optical traps, yet criticize the ineffectiveness of previous models due to the presence of the [[Doppler effect]]. In an effort to lessen the effect, they applied an alternative take on cooling [[magnesium]] ions below the room temperature precedent.<ref>{{Cite journal|last1=Wineland|first1=D. J.|last2=Drullinger|first2=R. E.|last3=Walls|first3=F. L.|title=Radiation-Pressure Cooling of Bound Resonant Absorbers|journal=Physical Review Letters|volume=40|issue=25|pages=1639\u20131642|doi=10.1103/physrevlett.40.1639|bibcode=1978PhRvL..40.1639W|year=1978|doi-access=free}}</ref> Using the electromagnetic trap to contain the magnesium ions, they bombarded them with a laser barely out of phase from the resonant [[frequency]] of the atoms.<ref name=":1">{{Cite journal|last=Bardi|first=Jason Socrates|date=2008-04-02|title=Focus: Landmarks: Laser Cooling of Atoms|url=https://physics.aps.org/story/v21/st11|journal=Physics|language=en-US|volume=21|doi=10.1103/physrevfocus.21.11}}</ref> The research from both groups served to illustrate the mechanical properties of light.<ref name=":0" /> Around this time, laser cooling techniques had allowed for temperatures lowered to around 40 [[kelvin]]s.\n\n [[William Daniel Phillips|William Phillips]] was influenced by the Wineland paper and attempted to mimic it, using neutral atoms instead of ions. In 1982, he published the first paper outlining the cooling of neutral atoms. The process he used is now known as the [[Zeeman slower]] and became one of the standard techniques for slowing an atomic beam. Now, temperatures around 240 microkelvins were reached. That threshold was the lowest researchers thought was possible. When temperatures then reached 43 microkelvins in an experiment by [[Steven Chu]],<ref>{{Cite web|url=http://hyperphysics.phy-astr.gsu.edu/hbase/optmod/lascool.html|title=Laser Cooling|website=hyperphysics.phy-astr.gsu.edu|access-date=2017-05-06}}</ref> the new low was explained by the addition of more atomic states in combination to laser polarization. Previous conceptions of laser cooling were decided to have been too simplistic.<ref name=":1" /> The major breakthroughs in the 70s and 80s in the use of laser light for cooling led to several improvements to preexisting technology and new discoveries with temperatures just above [[absolute zero]]. The cooling processes were utilized to make [[atomic clock]]s more accurate and to improve spectroscopic measurements, and led to the observation of a new [[state of matter]] at ultracold temperatures.<ref name=":2" /><ref name=":1" /> The new state of matter, the [[Bose\u2013Einstein condensate]], was observed in 1995 by [[Eric Allin Cornell|Eric Cornell]], [[Carl Wieman]], and [[Wolfgang Ketterle]].<ref>{{cite journal |last1=Chin |first1=Cheng |title=Ultracold atomic gases going strong |journal=National Science Review |date=1 June 2016 |volume=3 |issue=2 |pages=168\u2013170 |doi=10.1093/nsr/nwv073 |doi-access=free }}</ref>"}},
{"article_title": "Tricycle", "pageid": "172761", "revid": "1049149464", "timestamp": "2021-10-10T04:50:08Z", "history_paths": [["Tricycle --- Introduction ---", "History"]], "categories": ["cycle types", "tricycles", "vehicle technology", "physical activity and dexterity toys", "traditional toys", "wheeled vehicles"], "heading_tree": {"Tricycle --- Introduction ---": {"History": {}, "Associations": {}, "Wheel configurations": {"Delta": {}, "Tadpole": {}, "Other": {}}, "Types": {"Upright": {}, "Recumbent": {"Delta": {}, "Tadpole": {}, "Hand-crank": {}, "Tandem": {}}, "Rickshaw": {}, "Freight": {}, "Children's": {}, "Drift": {}, "Hand and foot": {}, "Tilting": {}}, "Conversion sets": {}, "Operation": {"Braking": {}}, "Records": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Tricycle --- Introduction ---|History": "[[File:Rollstuhl Farfler 1655.jpg|thumb|[[Stephan Farffler]]'s hand-controlled three-wheeled wheelchair]]\n[[File:\u0633\u0647\u200c\u0686\u0631\u062e\u0647.jpg|thumb|19th century tricycle used in Iran]]\n\nA three-wheeled [[wheelchair]] was built in 1655 or 1680 by a disabled German man, [[Stephan Farffler]], who wanted to be able to maintain his mobility. Since he was a watch-maker, he was able to create a vehicle that was powered by hand cranks.<ref name="Greene p. 21">{{Cite book | title=Free on Three: The Wild World of Human Powered Recumbent Tadpole Tricycles | publisher=iUniverse | author=Steve Greene | year=2011 | pages=21 | isbn=978-1462021604}}</ref><ref>{{Cite journal | title=Medical Innovations - Wheelchair | journal=Science Reporter | volume=44 | year=2007 | page=397 }}</ref>\n\nIn 1789, two French inventors<!---, Blanchard and Maguier----> developed a three-wheeled vehicle, powered by pedals; They called it the tricycle.<ref name="Greene p. 21" />\n\nIn 1818, British inventor Denis Johnson patented his approach to designing tricycles.{{Clarify|reason=citation needed|date=January 2021}} In 1876, [[James Starley]] developed the Coventry Lever Tricycle, which used two small wheels on the right side and a large drive wheel on the left side; power was supplied by hand levers. In 1877, Starley developed a new vehicle he called the Coventry Rotary, which was "one of the first rotary chain drive tricycles." Starley's inventions started a [[Bike boom|tricycling craze]] in Britain; by 1879, there were "twenty types of tricycles and multi-wheel cycles ... produced in Coventry, England, and by 1884, there were over 120 different models produced by 20 manufacturers." The first front steering tricycle was manufactured in 1881 by The Leicester Safety Tricycle Company of Leicester, England, which was brought to the market in 1882 costing \u00a318. They also developed a folding tricycle at the same time.\n\nOn May 8, 1888 in [[Washington, D.C.|Washington D.C]] Matthew A. Cherry patented new inventions to the Velocipede which could cary up-to three persons.<ref>{{Cite patent|title=Matthew a|gdate=1888-05-08|url=https://patents.google.com/patent/US382351A/en}}</ref>\n\nTricycles were used by riders who did not feel comfortable on the high wheelers, such as women who wore long, flowing dresses (see [[rational dress]])."}},
{"article_title": "Radiosonde", "pageid": "172851", "revid": "1048349803", "timestamp": "2021-10-05T15:12:11Z", "history_paths": [["Radiosonde --- Introduction ---", "History"]], "categories": ["telecommunications equipment", "atmospheric thermodynamics", "french inventions", "measuring instruments", "meteorological instrumentation and equipment", "russian inventions", "science and technology in the soviet union", "soviet inventions", "radio stations and systems itu", "international telecommunication union", "atmospheric sounding"], "heading_tree": {"Radiosonde --- Introduction ---": {"History": {}, "Operation": {}, "Routine radiosonde launches": {}, "Uses of upper air observations": {}, "Radio regulations": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Radiosonde --- Introduction ---|History": "[[File:PSM V53 D061 Train of tandem kites bearing a meteorograph.png|thumb|upright|left|Kites used to fly a meteograph]]\n[[File:PSM V53 D070 Meteorograph.jpg|thumb|upright|Meteograph used by the US Weather Bureau in 1898]]\n[[File:Wea01108 - Flickr - NOAA Photo Library.jpg|thumb|upright|U.S. Bureau of Standards personnel launch radiosonde near Washington, DC in 1936]]\n[[File:Launching radiosonde 1943.jpg|thumb|upright|US sailors launching a radiosonde during World War 2]]\n\nThe first flights of aerological instruments were done in the second half of the 19th century with kites and [[Thermo-hygrograph|meteographs]], a recording device measuring pressure and temperature that was recuperated after the experiment. This proved to be difficult because the kites were linked to the ground and were very difficult to manoeuvre in gusty conditions. Furthermore, the sounding was limited to low altitudes because of the link to the ground.\n\n[[Gustave Hermite]] and [[Georges Besan\u00e7on]], from France, were the first in 1892 to use a balloon to fly the meteograph. In 1898, [[L\u00e9on Teisserenc de Bort]] organized at the ''Observatoire de M\u00e9t\u00e9orologie Dynamique de [[Trappes]]'' the first regular daily use of these balloons. Data from these launches showed that the temperature lowered with height up to a certain altitude, which varied with the season, and then stabilized above this altitude. De Bort's discovery of the [[tropopause]] and [[stratosphere]] was announced in 1902 at the French Academy of Sciences.<ref name="MF2">{{cite web\n|url=http://www.meteo.fr/meteonet/decouvr/dossier/cnam/fr/s_rub_4_6.htm\n|work=D\u00e9couvrir : Mesurer l\u2019atmosph\u00e8re\n|title=Radiosondage\n|publisher=[[M\u00e9t\u00e9o-France]]\n|access-date=2008-06-30\n|language=fr\n|url-status=dead\n|archive-url=https://web.archive.org/web/20061207115202/http://www.meteo.fr/meteonet/decouvr/dossier/cnam/fr/s_rub_4_6.htm\n|archive-date=2006-12-07\n}}</ref> Other researchers, like [[Richard A\u00dfmann]] and [[William Henry Dines]], were working at the same times with similar instruments.\n\nIn 1924, Colonel William Blaire in the [[Signal Corps (United States Army)|U.S. Signal Corps]] did the first primitive experiments with weather measurements from balloon, making use of the temperature dependence of radio circuits. The first true radiosonde that sent precise encoded telemetry from weather sensors was invented in France by {{Interlanguage link|Robert Bureau|fr}}. Bureau coined the name "radiosonde" and flew the first instrument on January 7, 1929.<ref name="MF2"/><ref name="MF3">{{cite web\n|url=http://www.meteo.fr/meteonet/decouvr/a-z/html/224_curieux.htm\n|work=La m\u00e9t\u00e9o de A \u00e0 Z > D\u00e9finition\n|title=Bureau (Robert)\n|publisher=[[M\u00e9t\u00e9o-France]]\n|access-date=2008-06-30\n|language=fr\n|url-status=dead\n|archive-url=https://web.archive.org/web/20071029230225/http://www.meteo.fr/meteonet/decouvr/a-z/html/224_curieux.htm\n|archive-date=2007-10-29\n}}</ref> Developed independently a year later, [[Pavel Molchanov]] flew a radiosonde on January 30, 1930. Molchanov's design became a popular standard because of its simplicity and because it converted sensor readings to [[Morse code]], making it easy to use without special equipment or training.<ref name="ssht">DuBois, Multhauf and Ziegler, "The Invention and Development of the Radiosonde", ''Smithsonian Studies in History and Technology'', No. 53, 2002.</ref>\n\nWorking with a modified Molchanov sonde, Sergey Vernov was the first to use radiosondes to perform cosmic ray readings at high altitude. On April 1, 1935, he took measurements up to {{convert|13.6|km|abbr=on}} using a pair of [[Geiger counter]]s in an anti-coincidence circuit to avoid counting secondary ray showers.<ref name="ssht"/><ref>Vernoff, S. "Radio-Transmission of Cosmic Ray Data from the Stratosphere", ''Nature'', June 29, 1935.</ref> This became an important technique in the field, and Vernov flew his radiosondes on land and sea over the next few years, measuring the radiation's latitude dependence caused by the [[Earth's magnetic field]].\n\nIn 1936, the U.S. Navy assigned the [[U.S. Bureau of Standards|U.S. Bureau of Standards (NBS)]] to develop an official radiosonde for the Navy to use.<ref name=":0">{{Cite news|url=https://repository.si.edu/bitstream/handle/10088/2453/SSHT-0053_Lo_res.pdf?sequence=2&isAllowed=y|title=The Invention and Development of the Radiosonde, with a Catalog of Upper-Atmospheric Telemetering Probes in the National Museum of American History, Smithsonian Institution|last1=DuBois|first1=John|date=2002|access-date=July 13, 2018|publisher=Smithsonian Institution Press|last2=Multhauf|first2=Robert|last3=Ziegler|first3=Charles}}</ref> The NBS gave the project to [[Harry Diamond (engineer)|Harry Diamond]], who had previously worked on radio navigation and invented a blind landing system for airplanes.<ref>{{Cite journal|last=Gillmor|first=Stewart|date=December 26, 1989|title=Seventy Years of Radio Science, Technology, Standards, and Measurement at the National Bureau of Standards|journal=Eos, Transactions American Geophysical Union|volume=70|issue=52|pages=1571|doi=10.1029/89EO00403|bibcode=1989EOSTr..70.1571G}}</ref> The organization led by Diamond eventually (in 1992) became a part of the [[United States Army Research Laboratory|U.S. Army Research Laboratory]]. In 1937, Diamond, along with his associates Francis Dunmore and Wilbur Hinmann, Jr., created a radiosonde that employed audio-frequency subcarrier modulation with the help of a resistance-capacity relaxation oscillator. In addition, this NBS radiosonde was capable of measuring temperature and humidity at higher altitudes than conventional radiosondes at the time due to the use of electric sensors.<ref name=":0" /><ref name=":1">{{Cite journal|last=Clarke|first=E.T.|date=September 1941|title=The radiosonde: The stratosphere laboratory|journal=Journal of the Franklin Institute|volume=232|issue=3|pages=217\u2013238|doi=10.1016/S0016-0032(41)90950-X}}</ref>\n\nIn 1938, Diamond developed the first ground receiver for the radiosonde, which prompted the first service use of the NBS radiosondes in the Navy. Then in 1939, Diamond and his colleagues developed a ground-based radiosonde called the \u201cremote weather station,\u201d which allowed them to automatically collect weather data in remote and inhospitable locations.<ref name=":2">{{Cite book|url=https://books.google.com/books?id=hrizEY2BWOoC&pg=PA42|title=A Century of Excellence in Measurements, Standards, and Technology|last=Lide|first=David|publisher=CRC Press|year=2001|isbn=978-0-8493-1247-2|page=42}}</ref> By 1940, the NBS radiosonde system included a pressure drive, which measured temperature and humidity as functions of pressure.<ref name=":0" /> It also gathered data on cloud thickness and light intensity in the atmosphere.<ref>{{Cite web|url=http://nistdigitalarchives.contentdm.oclc.org/cdm/singleitem/collection/p16009coll19/id/1458/rec/11|title=NBS radio meteorographs :: Historic Photographs Collection|website=nistdigitalarchives.contentdm.oclc.org|access-date=2018-07-13}}</ref> Due to this and other improvements in cost (about $25), weight (> 1 kilogram), and accuracy, hundreds of thousands of NBS-style radiosondes were produced nationwide for research purposes, and the apparatus was officially adopted by the U.S. Weather Bureau.<ref name=":0" /><ref name=":1" />\n\nDiamond was given the Washington Academy of Sciences Engineering Award in 1940 and the IRE Fellow Award (which was later renamed the Harry Diamond Memorial Award) in 1943 for his contributions to radio-meteorology.<ref name=":2" /><ref>{{Cite web|url=https://ieeeusa.org/volunteers/awards-recognition/technical-achievement-awards/harry-diamond-award/harry-diamond-award-recipients/|title=Harry Diamond Memorial Award - Past Recipients - IEEE-USA|website=ieeeusa.org|language=en-US|access-date=2018-07-13}}</ref>\n\nThe expansion of economically important government [[weather forecasting]] services during the 1930s and their increasing need for data motivated many nations to begin regular radiosonde observation programs\n\nIn 1985, as part of the [[Soviet Union]]'s [[Vega program]], the two [[Venus]] probes, [[Vega 1]] and [[Vega 2]], each dropped a radiosonde into the [[atmosphere of Venus]]. The sondes were tracked for two days.\n\nAlthough modern [[remote sensing]] by satellites, aircraft and ground sensors is an increasing source of atmospheric data, none of these systems can match the vertical resolution ({{convert|30|m|abbr=on}} or less) and altitude coverage ({{convert|30|km|abbr=on}}) of radiosonde observations, so they remain essential to modern meteorology.<ref name="NOAA"/>\n\nAlthough hundreds of radiosondes are launched worldwide each day year-round, fatalities  attributed to  radiosondes are rare. The first known example was the electrocution of a lineman in the United States who was attempting to free a radiosonde from high-tension power lines in 1943.<ref>"Linemen Cautioned About Disengaging Radiosonde," Electrical World, 15 May 1943</ref><ref>{{Cite web|url=https://archive.today/20130208172229/http://radiosondemuseum.com/wp-content/gallery/mags/1943-radiosonde-fatality.jpg|title = 1943-radiosonde-fatality.JPG (758x1280 pixels)}}</ref> In 1970 an [[Antonov 24]] operating [[Aeroflot Flight 1661]] suffered a loss of control after striking a radiosonde in flight resulting in the death of all 45 people on board."}},
{"article_title": "Chroma subsampling", "pageid": "172944", "revid": "1031203540", "timestamp": "2021-06-30T09:44:34Z", "history_paths": [["Chroma subsampling --- Introduction ---", "History"]], "categories": ["film and video technology", "image compression"], "heading_tree": {"Chroma subsampling --- Introduction ---": {"Rationale": {"How subsampling works": {}}, "Sampling systems and ratios": {}, "Types of sampling and subsampling": {"4:4:4": {}, "4:2:2": {}, "4:2:1": {}, "4:1:1": {}, "4:2:0": {}, "4:1:0": {}, "3:1:1": {}}, "Artifacts": {"Gamma error": {}, "Out-of-gamut colors": {}}, "Terminology": {}, "History": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Chroma subsampling --- Introduction ---|History": "Chroma subsampling was developed in the 1950s by [[Alda Bedford]] for the development of color television by [[RCA]], which developed into the [[NTSC]] standard; luma\u2013chroma separation was developed earlier, in 1938 by [[Georges Valensi]]. Through studies, he showed that the human eye has high resolution only for black and white, somewhat less for "mid-range" colors like yellows and greens, and much less for colors on the end of the spectrum, reds and blues. Using this knowledge allowed RCA to develop a system in which they discarded most of the blue signal after it comes from the camera, keeping most of the green and only some of the red; this is chroma subsampling in the [[YIQ]] color space and is roughly analogous to 4:2:1 subsampling, in that it has decreasing resolution for luma, yellow/green, and red/blue."}},
{"article_title": "Sunglasses", "pageid": "173759", "revid": "1063118315", "timestamp": "2022-01-01T09:03:15Z", "history_paths": [["Sunglasses --- Introduction ---", "History"]], "categories": ["sunglasses", "american inventions", "ancient roman technology", "english inventions", "eyewear", "fashion accessories", "ophthalmology", "prevention", "sun"], "heading_tree": {"Sunglasses --- Introduction ---": {"History": {"First precursors: against [[snowblindness]]": {}, "Other precursers": {}, "Modern developments": {}}, "Functions": {"Visual clarity and comfort": {}, "Protection": {"Assessing protection": {}}, "Further functions": {}}, "Standards": {"Australia": {}, "Europe": {}, "United States": {}}, "Special-use": {"Land vehicle driving": {}, "Aircraft piloting": {}, "Sports": {}, "Space": {}}, "Construction": {"Lens": {}, "Frames": {}, "Nose bridge": {}}, "Fashion (alphabetically)": {"Aviator": {}, "Browline": {}, "Oversized": {}, "Shutter shades": {}, "Teashades": {}, "Wayfarer": {}, "Wrap-around": {}}, "Variants": {"Clip-on": {}, "Gradient lenses": {}, "Flip-up": {}, "Mirrored": {}}, "Other names": {}, "Producers": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Sunglasses --- Introduction ---|History": "[[File:Eskimo snowgoggles.jpg|thumb|[[Inuit]] [[snow goggles]] function by reducing exposure to sunlight, not by reducing its intensity]]\nSince prehistoric times until the spread of contemporary UV-shielding [[spectacle]]s, [[Inuit]] people made and wore [[Snow goggles]] of flattened walrus or caribou ivory with narrow slits to look through to block almost all of the harmful reflected rays of the sun.<ref>{{cite web|url=http://collections.civilisations.ca/public/pages/cmccpublic/alt-emupublic/Display.php?irn=855927|title=Prehistoric Inuit Snow-Goggles, circa 1200|access-date=2009-01-25|publisher=[[Canadian Museum of Civilization]] | date=1997-10-03|url-status=live|archive-url=https://web.archive.org/web/20110706173656/http://collections.civilisations.ca/public/pages/cmccpublic/alt-emupublic/Display.php?irn=855927|archive-date=2011-07-06}}<br />{{cite book|title=Origin of Everyday Things|last1=Acton|first1=Johnny|last2=Adams|first2=Tania|last3=Packer|first3=Matt|editor=Jo Swinnerton|year=2006|publisher=[[Sterling Publishing Company, Inc.]]|isbn=1-4027-4302-5|page=[https://archive.org/details/originofeveryday0000acto/page/254 254]|url-access=registration|url=https://archive.org/details/originofeveryday0000acto/page/254}}</ref><ref>Inuit hero 'Nanook' from the silent documentary film ''[[Nanook of the North]]'' (1922) wearing whale bone [https://s-media-cache-ak0.pinimg.com/236x/51/b0/57/51b057742fc5e30e5695bc9fe3a2afe3.jpg snow-goggles] {{webarchive |url=https://web.archive.org/web/20160304083959/https://s-media-cache-ak0.pinimg.com/236x/51/b0/57/51b057742fc5e30e5695bc9fe3a2afe3.jpg |date=March 4, 2016 }} Retrieved December 5, 2014</ref> In many different forms and with many different materials, the indigenous peoples of [[North America]] and northern Asia crafted highly efficient equipment to protect their eyes against the damaging effects of strong sunlight in icy circumstances.<ref>Thompson, Clive, ''[https://www.smithsonianmag.com/smithsonian-institution/snow-goggles-demonstrate-indigenous-ingenuity-180973738/ These Snow Goggles Demonstrate Thousands of Years of Indigenous Ingenuity]'', ''[[Smithsonian]]'', January, 2020</ref>\n\n It is said that the Roman emperor [[Nero]] liked to watch [[gladiator]] fights using cut [[emerald]]s. These, however, appear to have worked rather like mirrors.<ref>{{cite web|url=https://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Plin.+Nat.+37.16|title=Pliny the Elder, The Natural History, Book XXXVII, Ch. 16|publisher=Perseus.tufts.edu|access-date=2010-05-13}}</ref>\n\nThe first sunglasses, made from flat panes of [[smoky quartz]] called ''Ai Tai'', meaning \u2018dark clouds',<ref name="Science Museum Blog 2019">{{cite web | title=9 surprising moments in the history of sunglasses | website=Science Museum Blog | date=2019-05-07 | url=https://blog.sciencemuseum.org.uk/9-surprising-moments-in-the-history-of-sunglasses/ | access-date=2021-08-07}}</ref> which offered no corrective powers but did protect the eyes from [[Glare (vision)|glare]], were used in [[China]] in the 12th century or possibly earlier. Documents describe the use of such crystal sunglasses by judges in ancient Chinese [[court]]s to conceal their facial expressions while questioning witnesses.<ref>{{cite web|url=http://www.ideafinder.com/history/inventions/sunglasses.htm|title=Sunglasses History \u2013 The Invention of Sunglasses|access-date=2007-06-28|last=Ament|first=Phil|date=2006-12-04|work=The Great Idea Finder|publisher=Vaunt Design Group|url-status=dead|archive-url=https://web.archive.org/web/20070703224202/http://www.ideafinder.com/history/inventions/sunglasses.htm|archive-date=2007-07-03}}</ref><ref name="Vision">{{cite web | last=Vision | first=Website | title=Torquay Museum | website=Torquay Museum | url=http://www.torquaymuseum.org/explore/collections-spotlight/explorers/chinese-sunglasses | access-date=2021-08-07}}</ref>\n\nIn 1459 [[Nuno Fernandes]] made a request for a pair of spectacles to protect the eyes while horseriding in the snow against the glare coming from the snow, though no description of any actual spectacles is given.<ref name="College">{{cite web | last=Handley | first=Neil | title=Sunglasses | website=College of Optometrists | date=1914-09-18 | url=https://www.college-optometrists.org/the-college/museum/online-exhibitions/virtual-spectacles-gallery/sunglasses.html | access-date=2021-08-07}}</ref>\n\nKing [[Louis XIV]]'s court watched the [[Solar eclipse of May 12, 1706|1706 Solar eclipse]] through a [[Astronomical filter#Solar filters|telescope with a smoky glass filter attached]].<ref name="Thieme 2017">{{cite web | last=Thieme | first=Nick | title=A Brief History of Eclipse Glasses and the People Who Forgot to Wear Them | website=Slate Magazine | date=2017-08-18 | url=https://slate.com/technology/2017/08/a-history-of-eclipse-glasses-and-injuries.html | access-date=2021-08-07}}</ref>\n\nBy the 18th century tainted mirror-like framed [[Murano glass]]es had been used as so-called 'gondola glasses' (''vetri da gondola'' and also\u00a0''da dama'') by [[Venice|Venician]] women and children, to shield there eyes from the glare from the water in the canals. The [[Doge]] and other well-off Venecians such as possibly [[Goldoni]] sported in the later 18th century so-called 'goldoni glasses', tainted pairs of spectacles with pieces of cloth as sun guards on the sides of the glasses.<ref name="Venetian Cat">{{cite web | title=Ancient Designer Sunglasses, a Playwright and a War Hero | website=Venetian Cat | url=https://venetiancat.blogspot.com/2014/06/venetians-put-on-show-spectacles-fit.html | access-date=2021-08-07}}</ref><ref name="College"/>\n\n[[James Ayscough]] began experimenting with tinted lenses in spectacles in the mid-18th century, around 1752. These were not "sunglasses" as that term is now used; Ayscough believed that blue- or green-tinted glass could correct for specific vision impairments. Protection from the Sun's rays was not a concern for him.\n\n[[File:Zoom lunette ardente.jpg|thumb|[[Antoine Lavoisier]] conducting an experiment related to combustion generated by amplified sun light.]]\n\nOne of the earliest surviving depictions of a person wearing sunglasses is of the scientist [[Antoine Lavoisier]] in 1772 who worked with amplified sunlight. By the 19th century tainted spectacles were worn by railway travelers.<ref name="Science Museum Group Collection 2021">{{cite web | title=Turn pin spectacles with tinted, double folding lenses, France, 1790-1850 | website=Science Museum Group Collection | date=2021-08-07 | url=https://collection.sciencemuseumgroup.org.uk/objects/co151206/turn-pin-spectacles-with-tinted-double-folding-lenses-france-1790-1850-spectacles | access-date=2021-08-07}}</ref>\n\nPopularly it is claimed that yellow/amber and brown-tinted glasses have been used to alleviate symptoms of [[syphilis]] in the 19th and early 20th centuries, because sensitivity to light being one of the symptoms of the disease,{{Dubious|date=July 2009}} although no sources have been found which state prescription of such.<ref name="Dr Lindsey Fitzharris 2013">{{cite web | title=Ray-Ban's Predecessor? A Brief History of Tinted Spectacles | website=Dr Lindsey Fitzharris | date=2013-06-21 | url=https://www.drlindseyfitzharris.com/2013/06/21/ray-bans-predecessor-a-brief-history-of-tinted-spectacles/ | access-date=2021-08-07}}</ref>\n\nFrom the later 19th century short references of sunglasses have been found in reports, such as by a [[Walter Alden Dyer|Walter Alden]] in 1866, who wrote of soldiers using during the American Civil War (1861-5) 'shell spectacles' (''verres de cocquille'') to protect against sunlight on long marches, or by the British T. Longmore reporting in\u00a0''The Optical Manual''\u00a0(1885) of soldiers in Egypt being equipped with tinted glass 'eye protectors'. By 1895 sunglasses were mentioned in advertisements, such as in ''The Sioux City Journal''\u00a0(on June 13).<ref name="College"/>\n\n [[Jean-Marie-Th\u00e9odore Fieuzal]] (1836-1888) was the first to argue for UV protection with (yellow) shaded glasses and, by 1899, [[Rodenstock GmbH]] produced possibly the first sunglasses intended for shielding eyes from UV light and not just [[Glare (vision)|glare]].<ref name="Rodenstock">{{cite web | title=History | website=Rodenstock B2C | date=2014-07-28 | url=https://www.rodenstock.at/at14/de/unternehmen/ueber-rodenstock/history.html | language=de | access-date=2021-08-07}}</ref>\n\nIn 1913, [[William Crookes#Crookes sunglass lenses|Crookes lenses]]<ref>{{Cite web|url=http://museyeum.org/detail.php?name_title=Crookes&module=objects&type=advanced&kv=7151&record=18|title=The College of Optometrists|website=museyeum.org|access-date=Jun 24, 2020}}</ref> were introduced,<ref>{{Cite web|url=http://museyeum.org/detail.php?name_title=Crookes&module=objects&type=advanced&kv=20397&record=21&module=objects|title=The College of Optometrists|website=museyeum.org|access-date=Jun 24, 2020}}</ref> made from glass containing [[cerium]], which completely blocked ultraviolet light.<ref>{{Cite web|url=http://museyeum.org/results.php?name_title=Crookes&op-earliest_year==&op-latest_year==&module=objects&type=advanced|title=The College of Optometrists|website=museyeum.org|access-date=Jun 24, 2020}}</ref><ref>{{Cite web|url=https://www.collinsdictionary.com/dictionary/english/crookes-lens|title=Crookes lens definition and meaning | Collins English Dictionary|website=www.collinsdictionary.com|access-date=Jun 24, 2020}}</ref> In the [[Roaring Twenties|early 1920s]], the use of sunglasses started to become more widespread, especially among movie stars. <!-- It is commonly believed that this was to avoid recognition by fans, but an alternative reason sometimes given is that they often had red eyes from the powerful [[arc lamp]]s that were needed due to the extremely slow speed film stocks used.{{Citation needed|date=January 2009}} The stereotype persisted long after improvements in film quality and the introduction of [[ultraviolet]] filters had eliminated this problem. --> Inexpensive mass-produced sunglasses made from [[celluloid]] were first produced by [[Foster Grant|Sam Foster]] in 1929. Foster found a ready market on the [[beach]]es of [[Atlantic City, New Jersey]] where he began selling sunglasses under the name [[Foster Grant]] from a [[F. W. Woolworth Company|Woolworth]] on the [[boardwalk (entertainment district)#Atlantic City, New Jersey|Boardwalk]].<ref>{{cite web |url=http://www.articlesurfing.com/arts_and_crafts/the_history_of_sunglasses.html |title=The History Of Sunglasses |access-date=2012-05-01 |url-status=live |archive-url=https://web.archive.org/web/20120701000808/http://www.articlesurfing.com/arts_and_crafts/the_history_of_sunglasses.html |archive-date=2012-07-01 }}</ref> By 1938, ''[[Life (magazine)|Life]]'' magazine wrote of how sunglasses were a "new fad for wear on city streets ... a favorite affectation of thousands of women all over the U.S." It stated that 20 million sunglasses were sold in the United States in 1937 but estimated that only about 25% of American wearers needed them to protect their eyes.<ref name="life19380530">{{cite news | url=https://books.google.com/books?id=3EoEAAAAMBAJ&pg=PA31 | title=Dark Glasses are New Fad for Wear on City Streets | work=[[Life (magazine)|Life]] | date=1938-05-30 | access-date=2 July 2013 | pages=31\u201333 | url-status=live | archive-url=https://web.archive.org/web/20131231153256/http://books.google.com/books?id=3EoEAAAAMBAJ&lpg=PP1&pg=PA31#v=onepage&f=true | archive-date=31 December 2013 }}</ref> At the same time, sunglasses started to be used as aids for pilots and even produced for the gaining aviation sector, eventually adding to sunglasses as cultural icons and to their popularity. [[Polarizer|Polarized]] sunglasses first became available in 1936 when [[Edwin H. Land]] began experimenting with making lenses with his patented [[Polaroid (polarizer)|Polaroid]] filter. In 1947, the Armorlite Company began producing lenses with CR-39 resin.<ref>http://www.ppgoptical.com/getmedia/47e39594-6472-48e7-8e2c-8f48015284c8/CR39_50years_booklet.pdf</ref>\n\nAt present, [[Xiamen]], [[China]] is the world's largest producer of sunglasses with [[Port of Xiamen|its port]] exporting 120 million pairs each year.<ref>{{cite web  |title=China Expat city Guide Xiamen  |url=http://www.chinaexpat.com/article/2007/03/15/travel/chinas-50-best-websites-after-china-expat-course.html  |publisher=China Expat  |year=2008  |access-date=8 February 2009  |url-status=live  |archive-url=https://web.archive.org/web/20090124030851/http://chinaexpat.com/article/2007/03/15/travel/chinas-50-best-websites-after-china-expat-course.html  |archive-date=24 January 2009  }}</ref>"}},
{"article_title": "IMAX", "pageid": "173787", "revid": "1058649312", "timestamp": "2021-12-04T21:33:33Z", "history_paths": [["IMAX --- Introduction ---", "History"]], "categories": ["imax", "3d imaging", "canadian inventions", "film and video technology", "film formats", "motion picture film formats", "theatres"], "heading_tree": {"IMAX --- Introduction ---": {"History": {"Multiscreen Corporation": {}, "IMAX Corporation": {}, "Digital projection": {}}, "Technical aspects": {"Camera": {"Film cameras": {}, "Phantom 65 IMAX 3D digital camera": {}, "ARRI Alexa IMAX digital camera": {}, "Blackmagic URSA Mini Pro 12K": {}, "IMAX certified camera": {}}, "Film stock": {}, "Soundtrack \u2013 double-system": {}, "Projectors": {"Digital projection": {}, "Laser projection": {}}, "Theatres": {}}, "Variations": {"Dome and Omnimax": {}, "{{anchor|IMAX 3D}} 3D": {}, "HD": {}, "Digital": {}, "IMAXShift": {}, "Virtual reality": {}}, "Films": {"Entertainment": {}, "Use in Hollywood productions": {}, "DMR (Digital Media Remastering)": {}, "Feature films": {}, "In space exploration": {}}, "Awards": {}, "Other uses": {}, "Technical specifications": {}, "Competitors": {}, "Gallery": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"IMAX --- Introduction ---|History": "[[File:IMAX comparison.svg|thumb|A comparison between 35 mm and 15/70 mm negative areas.]]\nThe IMAX film standard uses [[70 mm film]] run through the projector horizontally. This technique produces an area that is nine times larger than the [[35 mm movie film|35 mm format]], and three times larger than 70 mm film which was run conventionally through the projector in a vertical orientation.<ref name="gizmodo.com">[https://gizmodo.com/how-regular-movies-become-imax-films-5250780 How Regular Movies Become "IMAX" Films], by Mark Wilson (Gizmodo.com, published May 29, 2009)</ref>\n\nThe desire to increase the visual impact of film has a long history. In 1929, [[Fox Film|Fox]] introduced [[70 mm Grandeur film|Fox Grandeur]], the first 70 mm film format, but it quickly fell from use. In the 1950s, the potential of [[35 mm movie film|35 mm film]] to provide wider projected images was explored in the processes of [[CinemaScope]] (1953) and [[VistaVision]] (1954), following multi-[[Movie projector|projector]] systems such as [[Cinerama]] (1952). While impressive, Cinerama was difficult to install and maintain, requiring careful alignment and synchronization of the multiple projectors. During [[Expo 67]] in Montreal, the [[National Film Board of Canada]]'s ''[[In the Labyrinth (film)|In the Labyrinth]]'' and Ferguson's ''Man and the Polar Regions'' both used complex multi-projector, multi-screen systems. Each encountered technical difficulties that led them to found a company called "Multiscreen", with the goal of developing a simpler approach.\n\n The single-projector/single-camera system they eventually settled upon was designed and built by Shaw based upon a novel "Rolling Loop" film-transport technology purchased from Peter Ronald Wright Jones, a machine shop worker from Brisbane, Australia.<ref>see {{US patent|3494524}}</ref>  Film projectors do not continuously flow the film in front of the bulb, but instead "stutter" the film travel so that each frame can be illuminated in a momentarily-paused still image. This requires a mechanical apparatus to buffer the jerky travel of the film strip. The older technology of running 70 mm film vertically through the projector used only five sprocket perforations on the sides of each frame; however, the IMAX method used fifteen perforations per frame.<ref name="gizmodo.com"/>  The previous mechanism was inadequate to handle this intermittent mechanical movement that was three times longer, and so Jones's invention was necessary for the novel IMAX projector method with its horizontal film feed. As it became clear that a single, large-screen image had more impact than multiple smaller ones and was a more viable product direction, Multiscreen changed its name to IMAX. Co-founder Graeme Ferguson explained how the name IMAX originated:<ref>{{cite web |last1=Wise |first1=Wyndham |title=IMAX at 30: An Interview with Graeme Ferguson |url=http://www.northernstars.ca/ferguson_graeme_article/ |website=NorthernStars.ca |archive-url=https://web.archive.org/web/20171207023535/http://www.northernstars.ca/ferguson_graeme_article/ |archive-date=2017-12-07 |url-status=dead}} Originally published in Take One magazine, Issue #17, Fall 1997.</ref>\n\n<blockquote>... the incorporation date [of the company was] September 1967. ... [The name change] came a year or two later. We first called the company Multiscreen Corporation because that, in fact, was what people knew us as. ... After about a year, our attorney informed us that we could never copyright or trademark Multivision. It was too generic. It was a descriptive word. The words that you can copyright are words like Kleenex or Xerox or Coca-Cola. If the name is descriptive, you can't trademark it so you have to make up a word. So we were sitting at lunch one day in a Hungarian restaurant in Montreal and we worked out a name on a placemat on which we wrote all the possible names we could think of. We kept working with the idea of maximum image. We turned it around and came up with IMAX.</blockquote>\n\nThe name change actually happened more than two years later, because a key patent filed on January 16, 1970, was assigned under the original name Multiscreen Corporation, Limited.<ref>{{Cite web|url=https://patents.google.com/patent/US3944349A/en|title=Shutter assembly|website=Patents.google.com|access-date=May 10, 2021}}</ref>  IMAX Chief Administration Officer Mary Ruby was quoted as saying, "Although many people may think "IMAX" is an [[acronym]], it is, in fact, a made-up word."<ref>{{Cite web|url=https://www.managingip.com/Article/1257879/Latest-News-Magazine/The-full-picture.html?ArticleId=1257879|title=Managing IP, INTA Daily News article|website=Managingip.com|access-date=May 10, 2021}}</ref>\n\n [[File:IMAX film projector 2011 Bradford.jpg|thumb|upright|IMAX projector with horizontal film reel]]\n''[[Tiger Child]]'', the first IMAX film, was demonstrated at [[Expo '70]] in [[Osaka, Japan]].<ref>{{cite web |url=http://www.ieee.ca/millennium/imax/imax_chronology.html |title=IMAX'S Chronology of Techonological (sic) Events |access-date=February 23, 2010 |publisher=IEEE Canada, Institute of Electrical and Electronics Engineers}}</ref> The first permanent IMAX installation was built at the [[Cinesphere]] theatre at [[Ontario Place]] in Toronto. It debuted in May 1971, showing the film ''[[North of Superior]]''. The installation remained in place<ref>{{cite web |url=http://www.imax.com/corporate/profile/historyMilestones/ |title=Corporate, History & Milestones |publisher=IMAX.com |access-date=July 3, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100704081254/http://www.imax.com/corporate/profile/historyMilestones/ |archive-date=July 4, 2010 |df=mdy-all }}</ref> during Ontario Place's hiatus for redevelopment. The Cinesphere was renovated while Ontario Place was closed and re-opened on November 3, 2017, with IMAX 70mm and IMAX with laser illumination.<ref>{{cite news |last1=Cheng |first1=Jennifer |title=Inside the newly restored Cinesphere at Ontario Place |url=https://torontolife.com/culture/movies-and-tv/ontario-place-cinesphere-reopening/ |access-date=11 November 2018 |work=Toronto Life |publisher=Toronto Life Publishing Company Limited |date=3 November 2017}}</ref>\n\nDuring [[Expo '74]] in [[Spokane, Washington]], an IMAX screen that measured {{convert|27|x|20|m|ft|abbr=on}} was featured in the US Pavilion (the largest structure in the expo). It became the first IMAX Theatre to not be partnered with any other brand of movie theatres. About five million visitors viewed the screen, which covered the viewer's total visual field when looking directly forward. This created a sensation of motion in most viewers, and [[motion sickness]] in some.\n\nAnother IMAX 3D theatre was also built in Spokane; however, its screen size is less than half. Due to protests, the City of Spokane officials decided to work with the IMAX Corporation to demolish the theatre, under the condition they renovate the former US Pavilion itself into IMAX's first permanent ''outdoor'' giant-screen theatre. The plan was to use material on the inside of the structure similar to that used when first constructed. However, it was expected to last only five years, due to weather conditions destroying previous materials.<ref>{{cite web |url= http://www.spokesman.com/stories/2016/sep/30/imax-theater-in-riverfront-park-headed-for-demolit/ |title= Imax theater in Riverfront Park headed for demolition; the fate of pavilion rides still in question |publisher= The Spokesmen-Review |date= Sep 30, 2016 |access-date= May 24, 2017}}</ref> Concept art has been released in videos featured on Spokane's renovation site, and its budget revealed that seating is planned for more than 2,000.<ref>{{cite web |url= http://riverfrontparknow.com/redevelopment/u-s-pavilion-shelters/ |archive-url= https://web.archive.org/web/20160216021903/http://riverfrontparknow.com/redevelopment/u-s-pavilion-shelters/ |url-status=dead |archive-date= February 16, 2016 |title= US Pavilion & Shelters |publisher= City of Spokane |access-date= May 24, 2017 }}</ref><ref>{{cite web |url= https://static.spokanecity.org/documents/parksrec/aboutus/planning/2014-riverfront-park-master-plan.pdf |title=2014 Riverfront Park Master Plan |publisher= City of Spokane |access-date=June 1, 2017}}</ref>\n\nThe first permanent IMAX Dome installation, the Eugene Heikoff and Marilyn Jacobs Heikoff Dome Theatre at the [[Reuben H. Fleet Science Center]], opened in [[San Diego]]'s [[Balboa Park, San Diego, California|Balboa Park]] in 1973. It doubles as a [[planetarium]] theater. The first permanent IMAX 3D theatre was built in [[Vancouver]], British Columbia, for ''[[Transitions (film)|Transitions]]'' at [[Expo '86]], and was in use until September 30, 2009.<ref>{{cite web |url= http://www.imax.com/vancouver/ |title=IMAX Theatre |publisher=Imax.com |date=October 1, 2009 |access-date=July 3, 2010}} (official site).</ref> It was located at the tip of [[Canada Place]], a Vancouver landmark.\n\n {{see also|#Digital}}\nIn 2008, IMAX extended its brand into traditional theaters with the introduction of Digital IMAX, a lower-cost system that uses two 2K digital projectors to project on a 1.90:1 aspect ratio screen. This lower-cost option, which allowed for the conversion of existing [[multiplex theater]] auditoriums, helped IMAX to grow from 299 screens worldwide at the end of 2007 to over 1,000 screens by the end of 2015.<ref name=results2015>{{cite press release|author1=IMAX Corporation|title=IMAX Corporation Reports Fourth-Quarter And Full-Year 2015 Financial Results|url=http://www.prnewswire.com/news-releases/imax-corporation-reports-fourth-quarter-and-full-year-2015-financial-results-300225647.html|publisher=PR Newswire|access-date=February 24, 2016|date=February 24, 2016}}</ref><ref>{{cite web|title=IMAX Corporation Form 10-K for the fiscal year ended December 31, 2007|url=http://media.corporate-ir.net/media_files/irol/11/118725/2007_IMAX_Annual_Report.pdf|date=March 14, 2008|access-date=2016-02-29}}</ref> {{As of|2017|9}}, there were 1,302 IMAX theatres located in 75 countries, of which 1,203 were in commercial multiplexes.<ref name="canada-vr">{{cite web|url=http://markets.businessinsider.com/news/stocks/IMAX-and-Cineplex-Launch-Canada-s-First-IMAX-VR-Centre-at-Scotiabank-Theatre-Toronto-1008432655|title=IMAX and Cineplex Launch Canada's First IMAX VR Centre at Scotiabank Theatre Toronto - Markets Insider|first=finanzen.net|last=GmbH}}</ref>\n\nThe switch to digital projection came at a steep cost in image quality, with [[2K resolution|2K]] projectors having roughly an order of magnitude less resolution than traditional IMAX film projectors. Maintaining the same 7-story screen size would only make this loss more noticeable, so many new theaters were instead built with significantly smaller screens. These newer theaters with much lower resolution and much smaller screens soon began to be referred to by the derogatory name "LieMAX", particularly because the company still marketed the new screens similarly to the old ones, without making the major differences clear to the public, going so far as to market the smallest "IMAX" screen, having 10 times less area, similarly to the largest while persisting with the same brand name.<ref>[https://www.npr.org/2014/05/02/308939700/maintaining-the-imax-experience-from-museum-to-multiplex Maintaining The IMAX Experience, From Museum To Multiplex], by Elizabeth Blair (NPR.org, May 2, 2014)</ref><ref>[http://www.lfexaminer.com/20100421shrinking-imax-screens.htm The Shrinking IMAX Screen] {{Webarchive|url=https://web.archive.org/web/20190525134659/http://www.lfexaminer.com/20100421shrinking-imax-screens.htm |date=May 25, 2019 }}, originally published in the LF Examiner, April 2010</ref>\n\nSince 2002, some feature films have been converted into IMAX format for displaying in IMAX theatres, and some have also been (partially) shot in IMAX. By late 2017, 1,302 IMAX theatre systems were installed in 1,203 commercial multiplexes, 13 commercial destinations, and 86 institutional settings in 75 countries,<ref name="canada-vr"/> with less than a quarter of those having the capability to show 70mm film at the resolution of the large format as originally conceived."}},
{"article_title": "Mezzotint", "pageid": "174252", "revid": "1063024781", "timestamp": "2021-12-31T20:30:12Z", "history_paths": [["Mezzotint --- Introduction ---", "History"]], "categories": ["engravings", "printmaking", "printing", "printing terminology", "visual arts media", "artistic techniques", "art of the dutch golden age", "science and technology in the dutch republic"], "heading_tree": {"Mezzotint --- Introduction ---": {"History": {}, "Light to dark method": {}, "Dark to light method": {}, "Printing": {}, "Detailed technique": {}, "Tone": {}, "Mezzotint engravers": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Mezzotint --- Introduction ---|History": "[[File:Arolsen Klebeband 01 273.jpg|thumb|[[Ludwig von Siegen]], ''[[Countess Amalie Elisabeth of Hanau-M\u00fcnzenberg]]'', 1642, is the first known ''mezzotint'', using the light to dark method.]]\nThe mezzotint printmaking method was invented by the German amateur artist [[Ludwig von Siegen]] (1609\u2013{{circa|1680}}). His earliest mezzotint print dates to 1642 and is a portrait of [[Countess Amalie Elisabeth of Hanau-M\u00fcnzenberg]]. This was made by working from light to dark. The rocker seems to have been invented by [[Prince Rupert of the Rhine]], a famous cavalry commander in the [[English Civil War]], who was the next to use the process, and took it to England. Sir [[Peter Lely]] saw the potential for using it to publicise his portraits, and encouraged a number of Dutch printmakers to come to England. [[Godfrey Kneller]] worked closely with [[John Smith (engraver)|John Smith]], who is said to have lived in his house for a period; he created about 500 mezzotints, some 300 copies of portrait paintings.\n\nBritish mezzotint collecting was a great craze from about 1760 to the [[Wall Street Crash of 1929|Great Crash]] of 1929, also spreading to America. The main area of collecting was British portraits; hit oil paintings from the [[Royal Academy Summer Exhibition]] were routinely, and profitably, reproduced in mezzotint throughout this period, and other mezzotinters reproduced older portraits of historical figures, or if necessary, made them up. The favourite period to collect was roughly from 1750 to 1820, the great period of the British portrait. There were two basic styles of collection: some concentrated on making a complete collection of material within a certain scope, while others aimed at perfect condition and quality (which declines in mezzotints after a relatively small number of impressions are taken from a plate), and in collecting the many "[[State (printmaking)|proof states]]" which artists and printers had obligingly provided for them from early on. Leading collectors included [[William Eaton, 2nd Baron Cheylesmore]] and the Irishman [[John Chaloner Smith]].<ref>Griffiths, 134\u2013137 and 141\u2013142</ref>"}},
{"article_title": "Aquatint", "pageid": "174263", "revid": "1061633140", "timestamp": "2021-12-22T22:26:13Z", "history_paths": [["Aquatint --- Introduction ---", "History"]], "categories": ["etching", "printmaking", "dutch inventions", "science and technology in the dutch republic"], "heading_tree": {"Aquatint --- Introduction ---": {"Technique": {}, "History": {"Early history": {}, "Revival": {}}, "Modern process": {}, "Famous examples": {}, "Notes": {}, "References": {}, "Further reading": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Aquatint --- Introduction ---|History": "[[File:The Public Promenade MET DT4549.jpg|thumb|upright=1.3|[[Philibert-Louis Debucourt]], ''The Public Promenade'', 1792. Printed in colour from various plates, using etching, engraving, and aquatint.  One of the leading achievements of the French 18th-century colour-print.]]\n\n \nA variety of early experiments aimed to add tonal effects to etching included the first use of a resin dust ground by the painter and printmaker Jan van de Velde IV in [[Amsterdam]], around 1650.  However none of these developed a technique that caught on with other printmakers.<ref>Griffiths, 92; Hind, AM (1963) A History of Engraving and Etching. Dover Publications, New York.</ref> Experimentation by several artists with somewhat different techniques reached a peak after about 1750, and as they were initially very secretive, the history of the emergence of the standard technique remains unclear.<ref>Griffiths, 93\u201394</ref>\n\nVarious claimants include the Swede [[Per Floding]] working with the Frenchman [[Fran\u00e7ois-Philippe Charpentier]] in 1761, J. B. Delafosse in 1766, working with the amateur [[Jean-Claude Richard]] (often rather misleadingly known as the Abb\u00e9 de Saint-Non) in 1766, and [[Jean-Baptiste Le Prince]] in 1768\u201369.  Le Prince was more effective than the others in publicizing his technique, publishing ''D\u00e9couverte du proc\u00e9d\u00e9 de graver au lavis'' in 1780, though he failed to sell his secret in his lifetime.  It was bought posthumously by the [[Acad\u00e9mie royale de peinture et de sculpture]] in 1782, who released it on an open basis.<ref>Griffiths, 94; Ives (MMA)</ref>\n[[File:Joseph Lycett - The residence of Edward Riley Esquire, Wooloomooloo, Near Sydney N. S. W. - Google Art Project.jpg|thumb|upright=1.3|[[Joseph Lycett]], ''The residence of Edward Riley Esquire, Wooloomooloo, Near Sydney N. S. W.'', 1825, hand-coloured aquatint and etching printed in dark blue ink.  Australian print in the tradition of British decorative production.  The artist had been [[Penal transportation|transported]] for forging bank notes.|left]]\nThough England was to become one of the countries using the technique most, the earliest English aquatints were not exhibited until 1772, by the cartographer [[Peter Perez Burdett]].  It was taken up by the watercolourist [[Paul Sandby]], who also seems to have introduced technical refinements as well as inventing the name "aquatint".<ref>Griffiths, 94; Ives; Ann V. Gunn, "Sandby, Greville and Burdett, and the 'Secret' of Aquatint," ''Print Quarterly,'' XXIX, no. 2, 2012, pp. 178\u2013180.</ref> In England artists such as Sandby and Thomas Gainsborough were attracted by the suitability of etched outlines with aquatint for reproducing the popular English landscape watercolours, which at this period usually also had been given an initial outline drawing in ink.  Publishers of prints and illustrations for expensive books, both important British markets at the time, also adopted the technique.  In all these areas, a print with etching and aquatint gave very satisfactory results when watercolour was added by relatively low-skilled painters copying a model, with a flat wash of colour on top of the varied tones of the aquatint.<ref>Griffiths, 94</ref> After the [[French Revolution]], one of the most successful publishers in London, the German [[Rudolf Ackermann]], had numbers of French refugees working on the floor above his shop in [[Strand, London|The Strand]] in London, each brushing a single colour and then passing the sheet down a long table.<ref>Mayor, 374\u2013376</ref>\n\nOver the same period in France there was sustained interest in techniques for true [[colour printing]] using multiple plates, which used multiple [[printmaking]] techniques which often included aquatint (or [[mezzotint]]) for tone.  Artists included [[Jean-Fran\u00e7ois Janinet]] and [[Philibert-Louis Debucourt]], whose ''La Promenade Publique'' is often thought the masterpiece of the style.<ref>Griffiths, 119</ref> Another branch of this French movement mostly used mezzotint for tone and came to specialize in illustrating medical textbooks.  This was at first led by [[Jacob Christoph Le Blon]] (1667\u20131741), who very nearly anticipated modern [[CMYK color model|CMYK]] colour separation and then carried on by his pupil [[Jacques Fabien Gautier d'Agoty]] and later members of the d'Agoty family until around 1800.<ref>Griffiths, 118\u2013119</ref>\n\n[[Goya]], maker of incontestably the greatest prints using aquatint, probably learned of the technique through Giovanni David from [[Genoa]], the first significant Italian to use it.  Goya used it, normally with etching and often burnishing and other techniques, in his great print series ''[[Los Caprichos]]'' (1799), ''[[Los Desastres de la Guerra]]'' (1810\u20131819), ''[[La Tauromaquia]]'' (1816) and ''[[Los disparates]]'' (c. 1816\u20131823).<ref>Ives (MMA); Griffiths, 94</ref>\n\n [[File:Mary Cassatt - Woman Bathing.jpg|thumb|[[Mary Cassatt]], ''Woman Bathing'', [[drypoint]] and aquatint, from three plates, 1890\u201391]]\nAfter a period of several decades in the central 19th century when the technique was little used, and definitively superseded for commercial uses,<ref>Mayor, 612\u2013614</ref> it was revived near the end of the century in France, by [[\u00c9douard Manet]], [[F\u00e9licien Rops]], [[Degas]], [[Pissarro]], [[Jacques Villon]] and other artists.<ref>Griffiths, 94</ref> In 1891, [[Mary Cassatt]], based in Paris, exhibited a series of highly original coloured drypoint and aquatint prints, including ''Woman Bathing'' and ''The Coiffure'', inspired by an exhibition of [[Japanese woodblock print]]s shown there the year before.  These used multiple blocks for the different colours.  Cassatt was attracted to the simplicity and clarity of Japanese design, and the skillful use of blocks of colour. In her interpretation, she used primarily light, delicate pastel colours and avoided black (a "forbidden" colour among the Impressionists).\n\nIt continued to be used in the 20th century, with the Czech [[T. F. \u0160imon]] and the German [[Johnny Friedlaender]] notably frequent users.  In the United States the printmaker [[Pedro Joseph de Lemos]] popularized aquatints in art schools with his publications (1919\u20131940), which simplified the cumbersome techniques, and with traveling exhibitions of his award-winning prints.<ref name="edwardsrw">{{cite book|last1=Edwards|first1=Robert W.| title=Pedro de Lemos, Lasting Impressions: Works on Paper| date=2015|publisher=Davis Publications Inc.| location=Worcester, Mass.|isbn=9781615284054|pages=67, 91 notes 355\u2013357}}</ref>"}},
{"article_title": "Wood gas", "pageid": "174818", "revid": "1041190130", "timestamp": "2021-08-29T04:03:25Z", "history_paths": [["Wood gas --- Introduction ---", "History"]], "categories": ["synthetic fuels", "fuel gas", "biofuels", "automotive engine technologies", "pyrolysis", "wood products", "industrial gases", "synthetic fuel technologies"], "heading_tree": {"Wood gas --- Introduction ---": {"History": {}, "Usage": {"Internal combustion engine": {}, "Stoves, cooking and furnaces": {}}, "Production": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Wood gas --- Introduction ---|History": "[[File:Petrol Substitutes in USE For Public Transport in Leeds, England C 1943 D15675.jpg|thumb|right|A bus, powered by wood gas generated by a gasifier on a trailer, Leeds, England c.1943]] \nThe first wood gasifier was apparently built by [[Gustav Bischof]] in 1839. The first vehicle powered by wood gas was built by [[Thomas Hugh Parker]] in 1901.<ref>{{ cite web | title = Thomas Hugh Parker | url = http://www.localhistory.scit.wlv.ac.uk/genealogy/Parker/ThomasHughParker.htm }}</ref>  Around 1900, many cities delivered [[syngas]] (centrally produced, typically from [[coal]]) to residences. [[Natural gas]] began to be used only in 1930.\n\nWood gas vehicles were used during [[World War II]] as a consequence of the rationing of fossil fuels. In Germany alone, around 500,000 "[[producer gas]]" vehicles were in use at the end of the war.  Trucks, buses, tractors, motorcycles, ships and trains were equipped with a wood gasification unit. In 1942, when wood gas had not yet reached the height of its popularity, there were about 73,000 wood gas vehicles in Sweden,<ref>Ekerholm, Helena. 'Cultural Meanings of Wood Gas as Automobile Fuel in Sweden, 1930-1945'. In Past and Present energy Societies: How Energy Connects Politics, Technologies and Cultures, edited by Nina M\u00f6llers and Karin Zachmann. Bielefeld: Transcript verlag, 2012.</ref> 65,000 in France, 10,000 in Denmark, and almost 8,000 in Switzerland. In 1944, Finland had 43,000 "woodmobiles", of which 30,000 were buses and trucks, 7,000 private vehicles, 4,000 tractors and 600 boats.<ref>[http://www.lowtechmagazine.com/2010/01/wood-gas-cars.html Wood gas vehicles: firewood in the fuel tank] Low-tech Magazine, January 18, 2010</ref>\n\nWood gasifiers are still manufactured in China and Russia for automobiles and as power generators for industrial applications. Trucks retrofitted with wood gasifiers are used in [[North Korea]]<ref>{{cite web|url=http://blogs.scientificamerican.com/plugged-in/how-north-korea-fuels-its-military-trucks-with-trees/|title=How North Korea Fuels Its Military Trucks With Trees|author=David Wogan|publisher=Scientific American|date=January 2, 2013|access-date=June 22, 2016}}</ref> in rural areas, particularly on the roads of the east coast."}},
{"article_title": "Light-on-dark color scheme", "pageid": "175004", "revid": "1057957209", "timestamp": "2021-11-30T16:59:36Z", "history_paths": [["Light-on-dark color scheme --- Introduction ---", "History"]], "categories": ["user interfaces", "display technology", "color schemes", "computer graphics"], "heading_tree": {"Light-on-dark color scheme --- Introduction ---": {"History": {}, "Energy usage": {}, "Issues with the web": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Light-on-dark color scheme --- Introduction ---|History": "[[File:Zork on CRT display.jpg|thumb|The [[Zork]] videogame running on a green-on-black CRT display]]\nPredecessors of modern computer screens, such as cathode-ray oscillographs, oscilloscopes, etc., tended to plot graphs and introduce other content as glowing traces on a black background.\n\nWith the introduction of computer screens, originally user interfaces were formed on [[cathode ray tube|CRT]]s like those used for oscillographs or oscilloscopes. The [[phosphor]] was normally a very dark color, and lit up brightly when the [[electron beam]] hit it, appearing to be white, green, blue, or amber on a black background, depending on phosphors applied on a [[monochrome]] screen. [[RGB]] screens continued to operate similarly, using all the beams set to "on" to form white.\n\nWith the advent of [[teletext]], research was done into which primary and secondary light colors and combinations worked best for this new medium.<ref>{{Cite web|last=Petterson|first=Rune|date=March 1985|title=Use of Colors in Teletext and Videotex|url=https://www.researchgate.net/publication/281936183_Use_of_Colors_in_Teletext_and_Videotex|url-status=live|website=[[ResearchGate]]}}</ref> Cyan or yellow on black was typically found to be optimal from a palette of black, red, green, yellow, blue, magenta, cyan and white.\n\nThe opposite color set, a '''dark-on-light color scheme''', was originally introduced in [[WYSIWYG]] [[word processor]]s to simulate ink on paper, and became the norm.\n\nIn early 2018, designer Sylvain Boyer extended the dark mode concept to the core interface of smartphones with OLED screens to save power consumption.<ref>{{Cite web|url=https://www.fastcompany.com/90160980/this-brilliant-smartphone-ui-saves-your-battery-and-looks-classy-af|title=This Smartphone UI Saves Your Battery (And Looks Classy AF)|first=Mark|last=Wilson|website=Fast Company}}</ref><ref>{{Cite web|url=https://www.trendhunter.com/trends/friendlui|title=Sylvain Boyer Designs the Friendlui Phone with Organic Elements|first=Amy|last=Duong|website=Trend Hunter}}</ref>\n\n[[Firefox]] and [[Chromium (web browser)|Chromium]] have optional dark theme for all internal screens, and in 2019, Apple announced that a light-on-dark mode would be available across all native applications in [[iOS 13]] and [[iPadOS]]. It will also be possible for third-party developers to implement their own dark themes.<ref>{{Cite web|url=https://www.theverge.com/2019/6/3/18647199/ios-13-dark-mode-apple-features-battery-saving-release-date-wwdc-2019|title=Dark mode is coming to iOS 13|last=Porter|first=Jon|date=2019-06-03|website=The Verge|access-date=2019-06-05}}</ref>\n\nIn 2019, a "prefers-color-scheme" option was created for [[Front-end web development|front-end web developers]], being a [[CSS]] property that signals a user's choice for their system to use a light or dark color theme.<ref name=":0" />"}},
{"article_title": "Plasma display", "pageid": "175859", "revid": "1059183130", "timestamp": "2021-12-07T23:15:10Z", "history_paths": [["Plasma display --- Introduction ---", "History"]], "categories": ["display technology", "american inventions", "hungarian inventions"], "heading_tree": {"Plasma display --- Introduction ---": {"General characteristics": {}, "Plasma display advantages and disadvantages": {"Advantages": {}, "Disadvantages": {}}, "Native plasma television resolutions": {"Enhanced-definition plasma television": {"ED resolutions": {}}, "High-definition plasma television": {}}, "Design": {}, "Contrast ratio": {}, "Screen burn-in": {}, "Environmental impact": {}, "History": {"Early development": {}, "1980s": {}, "1990s": {}, "2000s": {}, "2010s": {}}, "Notable display manufacturers": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Plasma display --- Introduction ---|History": "[[File:Platovterm1981.jpg|right|240px|thumb|Plasma displays were first used in PLATO computer terminals. This PLATO V model illustrates the display's monochromatic orange glow seen in 1981.<ref>[[Google Book Search|Google books]] \u2013 [https://books.google.com/books?id=PaFsMI_e88kC&pg=PA43&lpg=PA43&dq=PLATO+plasma&source=bl&ots=16VvtgmNnP&sig=XnikauH2MqQATLFf9uuYopkdHsY&hl=en&ei=uus6SseeNKO7jAfQ-tmjDQ&sa=X&oi=book_result&ct=result&resnum=4 Michael Allen's 2008 E-Learning Annual By Michael W. Allen]</ref>]]\n\n[[K\u00e1lm\u00e1n Tihanyi]], a Hungarian engineer, described a proposed flat-panel plasma display system in a 1936 paper.<ref>{{cite web |url=http://seura.com/flat-panel_tv_en.pdf |title=Kalman Tihanyi's plasma television |archive-url=https://web.archive.org/web/20140426233227/http://seura.com/flat-panel_tv_en.pdf |archive-date=2014-04-26 |access-date=2014-04-25}}</ref>\n\nThe first practical plasma video display was co-invented in 1964 at the [[University of Illinois at Urbana\u2013Champaign]] by [[Donald Bitzer]], [[H. Gene Slottow]], and graduate student Robert Willson for the [[PLATO (computer system)|PLATO computer system]].<ref name="plasmaaward">{{cite web|url=http://www.engr.ncsu.edu/news/awards/bitzer2.html|title=Bitzer Wins Emmy Award for Plasma Screen Technology|url-status=dead|archive-url=https://web.archive.org/web/20160304040548/http://www.engr.ncsu.edu/news/awards/bitzer2.html|archive-date=2016-03-04}}</ref><ref name=plasma_invention_alumni>{{cite web|url=https://ece.illinois.edu/newsroom/article/224|title=ECE Alumni wins award for inventing the flat-panel plasma display|date=Oct 23, 2002|access-date=Jan 11, 2018}}</ref> The original neon orange monochrome Digivue display panels built by glass producer [[Owens-Illinois]] were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images.<ref>Brian Dear, Chapter 6 \u2013 Gas and Glass, [https://books.google.com/books?id=D5ZBDwAAQBAJ&pg=PA92 ''The Friendly Orange Glow''], Pantheon Books, New York, 2017; pages 92-111 cover the development and first stages AC plasma panel commercialization.</ref> A long period of sales decline occurred in the late 1970s because semiconductor memory made [[Cathode ray tube|CRT display]]s cheaper than the $2500 [[United States dollar|USD]] {{nowrap|512 \u00d7 512}} PLATO plasma displays.<ref>Brian Dear, Chapter 22 \u2013 The Business Opportunity, [https://books.google.com/books?id=D5ZBDwAAQBAJ&pg=PA413 The Friendly Orange Glow], Pantheon Books, New York, 2017; pages 413\u2013417 cover CDC's decision to use CRTs with cheap video-RAM instead of plasma panels in 1975.</ref> Nonetheless, the plasma displays' relatively large screen size and 1 inch thickness made them suitable for high-profile placement in lobbies and stock exchanges.\n\n[[Burroughs Corporation]], a maker of adding machines and computers, developed the Panaplex display in the early 1970s. The Panaplex display, generically referred to as a gas-discharge or gas-plasma display,<ref name="Webopedia1">{{cite web|url=http://www.webopedia.com/TERM/G/gas_plasma_display.html|title=What is gas-plasma display?|date=September 1996|publisher=Webopedia|access-date=2009-04-27}}</ref> uses the same technology as later plasma video displays, but began life as a [[seven-segment display]] for use in [[adding machine]]s. They became popular for their bright orange luminous look and found nearly ubiquitous use throughout the late 1970s and into the 1990s in [[cash register]]s, [[calculator]]s, [[pinball machines]], aircraft [[avionics]] such as [[airband|radios]], [[navigation|navigational instruments]], and [[stormscope]]s; test equipment such as [[frequency counter]]s and [[multimeter]]s; and generally anything that previously used [[nixie tube]] or [[numitron]] displays with a high digit-count. These displays were eventually replaced by LEDs because of their low current-draw and module-flexibility, but are still found in some applications where their high brightness is desired, such as pinball machines and avionics.\n\n In 1983, [[IBM]] introduced a {{convert|19|in|cm|adj=on}} orange-on-black monochrome display (model 3290 'information panel') which was able to show up to four simultaneous [[IBM 3270]] terminal sessions. By the end of the decade, orange monochrome plasma displays were used in a number of high-end [[alternating current|AC]]-powered [[portable computers]], such as the [[Compaq Portable 386]] (1987) and the [[IBM P75]] (1990). Plasma displays had a better contrast ratio, viewability angle, and less motion blur than the LCDs that were available at the time, and were used until the introduction of active-matrix color LCD displays in 1992.<ref>{{cite web |title=The chronicles of gas-plasma |url=https://www.retropaq.com/the-miracle-of-gas-plasma/ |website=Retropaq.com|date=20 October 2020 }}</ref>\n\nDue to heavy competition from monochrome LCDs used in laptops of the era and the high costs of plasma display technology, in 1987 IBM planned to shut down its factory in upstate New York, the largest plasma plant in the world, in favor of manufacturing [[mainframe computer]]s, which would have left development to Japanese companies.<ref name="news.cnet.com">[http://news.cnet.com/Getting-a-charge-out-of-plasma-TV/2100-1041_3-6191482.html Ogg, E., "Getting a charge out of plasma TV"], CNET News, June 18, 2007, retrieved 2008-11-24.</ref> Dr. [[Larry F. Weber]], a [[University of Illinois]] ECE PhD (in plasma display research) and staff scientist working at CERL (home of the [[PLATO System]]) co-founded a startup company Plasmaco with [[Stephen Globus]], as well as James Kehoe, who was the IBM plant manager, and bought the plant from IBM for US$50,000. Weber stayed in Urbana as CTO until 1990, then moved to upstate New York to work at Plasmaco.\n\n In 1992, [[Fujitsu]] introduced the world's first 21-inch (53 cm) full-color display. It was based on technology created at the [[University of Illinois at Urbana\u2013Champaign]] and [[NHK Science & Technology Research Laboratories]].\n\nIn 1994, Weber demonstrated a color plasma display at an industry convention in San Jose. [[Panasonic Corporation]] began a joint development project with Plasmaco, which led in 1996 to the purchase of Plasmaco, its color AC technology, and its American factory for US$26 million.\n\nIn 1995, Fujitsu introduced the first {{convert|42|in|cm|0|adj=on}} plasma display panel;<ref name=ergwnyu>{{cite news |url=https://news.google.com/newspapers?id=3EZWAAAAIBAJ&pg=6111%2C5949387 |work=Eugene Register-Guard |location=(Oregon) |agency=Associated Press |last=Thurber |first=David |title=Flat screen TVs coming soon to a wall near you |date=August 25, 1995 |page=9C}}</ref><ref>Weber, L. F., "History of the Plasma Display Panel," IEEE Transactions on Plasma Science, Vol. 34, No. 2, (April, 2006), pp.268-278.</ref> it had 852\u00d7480 resolution and was progressively scanned.<ref>[http://www.tech-notes.tv/Archive/tech_notes_004.htm Mendrala, Jim, "Flat Panel Plasma Display"], ''North West Tech Notes'', No. 4, June 15, 1997, retrieved 2009-01-29.</ref> Two years later, [[Philips]] introduced the first large commercially available flat-panel TV, using the Fujitsu panels. It was available at four [[Sears]] locations in the US for $14,999, including in-home installation. [[Pioneer Corporation|Pioneer]] also began selling plasma televisions that year, and other manufacturers followed. By the year 2000 prices had dropped to $10,000.\n\n In the year 2000, the first 60-inch plasma display was developed by Plasmaco. Panasonic was also reported to have developed a process to make plasma displays using ordinary window glass instead of the much more expensive "high strain point" glass.<ref>{{Cite news|url=https://www.wsj.com/articles/SB967587676614566981#:~:text=When%20plasma%2Dgas%20technology%20was,quality%20standards%20for%20the%20sets.|title = Passion for Plasma Fuels Creation of First 60-Inch Flat-Screen TV|newspaper = Wall Street Journal|date = 30 August 2000}}</ref> High strain point glass is made similarly to conventional float glass, but it is more heat resistant, deforming at higher temperatures. High strain point glass is normally necessary because plasma displays have to be baked during manufacture to dry the rare-earth phosphors after they are applied to the display. However, high strain point glass may be less scratch resistant.<ref>{{Cite web|url=https://www.glassonline.com/central-glass-to-produce-speciality-glass/|title = Central Glass to produce speciality glass|date = 19 November 2002}}</ref><ref>{{Cite web|url=https://patents.google.com/patent/US20080113857|title = High Strain-Point Glass Composition for Substrate}}</ref><ref>{{Cite web|url=https://patents.google.com/patent/US6998578|title = Baking system for plasma display panel and layout method for said system}}</ref><ref>Duisit, G., Gaume, O., & El Khiati, N. (2003). 23.4: High Strain Point Glass with Improved Chemical Stability and Mechanical Properties for FPDs. SID Symposium Digest of Technical Papers, 34(1), 905. doi:10.1889/1.1832431</ref>\n\n[[File:Evolution of 21st century plasma displays.jpg|thumb|175px|Average plasma displays have become one quarter the thickness from 2006 to 2011]]\nIn late 2006, analysts noted that LCDs had overtaken plasmas, particularly in the 40-inch (100 cm) and above segment where plasma had previously gained market share.<ref>[https://www.nbcnews.com/id/15916808 "Shift to large LCD TVs over plasma"], ''MSNBC'', November 27, 2006, retrieved 2007-08-12.</ref> Another industry trend was the consolidation of plasma display manufacturers, with around 50 brands available but only five manufacturers. In the first quarter of 2008, a comparison of worldwide TV sales broke down to 22.1 million for direct-view CRT, 21.1 million for LCD, 2.8 million for plasma, and 0.1 million for rear projection.<ref>[http://www.digitalhome.ca/content/view/2538/206 "LCD televisions outsell plasma 8 to 1 worldwide"] {{webarchive|url=https://web.archive.org/web/20090522001447/http://www.digitalhome.ca/content/view/2538/206/ |date=2009-05-22 }}, ''Digital Home'', 21 May 2008, retrieved 2008-06-13.</ref>\n\nUntil the early 2000s, plasma displays were the most popular choice for [[HDTV]] [[flat panel display]] as they had many benefits over LCDs. Beyond plasma's deeper blacks, increased contrast, faster response time, greater color spectrum, and wider viewing angle; they were also much bigger than LCDs, and it was believed that LCDs were suited only to smaller sized televisions. However, improvements in [[VLSI]] fabrication narrowed the technological gap. The increased size, lower weight, falling prices, and often lower electrical power consumption of LCDs made them competitive with plasma television sets.\n\nScreen sizes have increased since the introduction of plasma displays. The largest plasma video display in the world at the 2008 [[Consumer Electronics Show]] in [[Las Vegas Valley|Las Vegas]], [[Nevada]], was a {{convert|150|in|cm|adj=on}} unit manufactured by Matsushita Electric Industrial (Panasonic) standing 6 ft (180 cm) tall by 11 ft (330 cm) wide.<ref>[https://www.independent.co.uk/life-style/gadgets-and-tech/news/6ft-by-150-inches--and-thats-just-the-tv-768862.html Dugan, Emily., "6ft by 150 inches \u2013 and that's just the TV"], ''The Independent'', 8 January 2008, retrieved 2009-01-29.</ref><ref>[[PC Magazine|PCMag.com]] \u2013 [https://www.pcmag.com/article2/0,2817,2246186,00.asp Panasonic's 150-Inch "Life Screen" Plasma Opens CES]</ref>\n\n At the 2010 Consumer Electronics Show in Las Vegas, Panasonic introduced their 152" 2160p 3D plasma. In 2010, Panasonic shipped 19.1 million plasma TV panels.<ref name=post>{{cite news |title=Panasonic celebrates higher plasma TV sales for 2010, sets prices for 2011 |work=EnGadget |date=March 1, 2011 |url=https://www.engadget.com/2011/03/01/panasonic-celebrates-higher-plasma-tv-sales-for-2010-sets-pric/ }}</ref>\n\nIn 2010, the shipments of plasma TVs reached 18.2 million units globally.<ref name="st2011-09-12">[http://www.hdtvtest.co.uk/news/lcd-tv-market-larger-plasma-201102201032.htm LCD TV Market Ten Times Larger Than Plasma TVs On Units-Shipped Basis], 20 February 2011, Jonathan Sutton, hdtvtest.co.uk, retrieved at September 12, 2011</ref> Since that time, shipments of plasma TVs have declined substantially. This decline has been attributed to the competition from liquid crystal (LCD) televisions, whose prices have fallen more rapidly than those of the plasma TVs.<ref>{{cite news |title=LCD TV Growth Improving, As Plasma and CRT TV Disappear, According to NPD DisplaySearch |date=April 16, 2014 |work=PRWeb |url=http://www.prweb.com/releases/2014/04/prweb11768569.htm |quote=Of course, the growth of LCD comes at the expense of plasma and CRT TV shipments, which are forecast to fall 48 percent and 50 percent, respectively, in 2014. In fact, both technologies will all but disappear by the end of 2015, as manufacturers cut production of both technologies in order to focus on LCD, which has become more competitive from a cost standpoint.}}</ref> In late 2013, Panasonic announced that they would stop producing plasma TVs from March 2014 onwards.<ref>{{cite news |url=http://reviews.cnet.com/8301-33199_7-57610230-221/tv-shoppers-now-is-the-time-to-buy-a-panasonic-plasma |title=TV shoppers: Now is the time to buy a Panasonic plasma |newspaper=CNET |date=October 31, 2013 }}</ref> In 2014, LG and Samsung discontinued plasma TV production as well,<ref>{{cite news |url=https://www.pcmag.com/article2/0,2817,2471112,00.asp| title=With LG Out, Plasma HDTVs Are Dead| author=Will Greenwald| date=October 28, 2014| website=[[PC Magazine]]}}</ref><ref>{{cite news |url=https://www.cnet.com/news/samsung-reportedly-ending-plasma-tv-production/| title=Samsung to end plasma TV production this year| author=David Katzmaier| date=July 2, 2014| website=[[CNET]]}}</ref> effectively killing the technology, probably because of lowering demand."}},
{"article_title": "Overhead line", "pageid": "176752", "revid": "1059883591", "timestamp": "2021-12-12T06:10:29Z", "history_paths": [["Overhead line --- Introduction ---", "History"]], "categories": ["electric rail transport", "tram technology", "pylons", "electric power infrastructure", "electric power distribution"], "heading_tree": {"Overhead line --- Introduction ---": {"Overview": {}, "Construction": {"Parallel overhead lines": {}}, "Types of wires": {}, "Tensioning": {}, "Breaks": {"Section break": {}, "Neutral section (phase break)": {}, "Dead section": {}, "Gaps": {}}, "Overhead conductor rails": {}, "Crossings": {"Australia": {}, "Greece": {}, "Italy": {}}, "Multiple overhead lines": {}, "Overhead catenary": {"Height": {}}, "Problems with overhead equipment": {}, "History": {}, "Gallery": {}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Overhead line --- Introduction ---|History": "The first tram with overhead lines was presented by [[Werner von Siemens]] at the [[International Exposition of Electricity|1881 International Exposition of Electricity]] in [[Paris]]: the installation was removed after that event. In October 1883, the first permanent tram service with overhead lines was on the [[M\u00f6dling and Hinterbr\u00fchl Tram]] in Austria. The trams had bipolar overhead lines, consisting of two U-pipes, in which the pantographs hung and ran like shuttles. From April to June 1882, Siemens had tested a similar system on his [[Electromote]], an early precursor of the [[trolleybus]].\n\nMuch simpler and more functional was an overhead wire in combination with a pantograph borne by the vehicle and pressed at the line from below. This system, for rail traffic with a unipolar line, was invented by [[Frank J. Sprague]] in 1888. From 1889 it was used at the [[Richmond Union Passenger Railway]] in [[Richmond, Virginia]], pioneering electric traction."}},
{"article_title": "Immortality", "pageid": "177052", "revid": "1062716203", "timestamp": "2021-12-30T03:00:02Z", "history_paths": [["Immortality --- Introduction ---", "Physical immortality"], ["Immortality --- Introduction ---", "Religious views"]], "categories": ["immortality", "afterlife", "life extension", "mythological powers", "technological utopianism"], "heading_tree": {"Immortality --- Introduction ---": {"Definitions": {"Scientific": {}, "Religious": {}}, "Physical immortality": {"Causes of death": {"Aging": {}, "Disease": {}, "Trauma": {}, "Environmental change": {}}, "Biological immortality": {"Biologically immortal species": {}, "Evolution of aging": {}, "Immortality of the germ line": {}}, "Prospects for human biological immortality": {"Life-extending substances": {}, "Technological immortality, biological machines, and  \"swallowing the doctor\"": {}, "Cryonics": {}, "Mind-to-computer uploading": {}, "Cybernetics": {}, "Digital immortality": {}}}, "Religious views": {"Ancient Greek religion": {}, "Buddhism": {}, "Christianity": {}, "Hinduism": {}, "Judaism": {}, "Taoism": {}, "Zoroastrianism": {}}, "Philosophical arguments for the immortality of the soul": {"Alcmaeon of Croton": {}, "Plato": {}, "Plotinus": {}, "Metochites": {}, "Avicenna": {}, "Aquinas": {}, "Descartes": {}, "Leibniz": {}, "Moses Mendelssohn": {}}, "Ethics": {"Undesirability": {}}, "Sociology": {}, "Politics": {}, "Symbols": {}, "See also": {}, "Footnotes": {}, "References": {}, "Further reading": {}, "External links": {"Religious and spiritual prospects for immortality": {}, "In literature": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Immortality --- Introduction ---|Physical immortality": "Physical immortality is a state of life that allows a person to avoid death and maintain conscious thought. It can mean the unending existence of a person from a physical source other than organic life, such as a computer.\n\nPursuit of physical immortality before the advent of modern science included [[alchemy|alchemists]] seeking to create the [[Philosopher's Stone]],<ref name="Paracelsus">Theophrastus Paracelsus. ''The Book of the Revelation of Hermes''. 16th century</ref> and various cultures' legends such as the [[Fountain of Youth]] or the [[Peaches of Immortality]] inspiring attempts at discovering [[Elixir of life|elixirs of life]].\n\nModern scientific trends, such as [[cryonics]], [[digital immortality]], breakthroughs in [[rejuvenation (aging)|rejuvenation]], or predictions of an impending [[technological singularity]], to achieve genuine human physical immortality, must still overcome all causes of death to succeed:\n\n {{Main|Death}}\nThere are three main causes of death: [[aging]], [[disease]], and [[physical trauma|injury]].<ref>{{cite journal |last=Hayflick |first=L. |year=2007 |title=Biological aging is no longer an unsolved problem |journal=Annals of the New York Academy of Sciences |volume=1100 |issue=1 |pages=1\u201313 |doi=10.1196/annals.1395.001 |pmid=17460161 |bibcode=2007NYASA1100....1H |s2cid=14685889}}{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Such issues can be resolved with the solutions provided in research to any end providing such alternate theories at present that require unification.\n\n [[Aubrey de Grey]], a leading researcher in the field,<ref name="Garreau">{{cite news |first=Joel |last=Garreau |author-link=Joel Garreau |date=31 October 2007 |title=The Invincible Man |newspaper=[[The Washington Post]] |page=C\u201101 |url=https://www.washingtonpost.com/wp-dyn/content/article/2007/10/30/AR2007103002222_pf.html}}</ref> defines [[aging]] as "a collection of cumulative changes to the [[molecular]] and [[cell (biology)|cellular]] structure of an adult [[organism]], which result in essential [[metabolic]] processes, but which also, once they progress far enough, increasingly disrupt metabolism, resulting in [[pathology]] and death." The current causes of aging in humans are cell loss (without replacement), [[DNA damage theory of aging|DNA damage]], [[oncology|oncogenic]] [[cell nucleus|nuclear]] [[mutation]]s and [[epimutation]]s, cell [[senescence]], [[mitochondria]]l mutations, [[lysosomal]] aggregates, extracellular aggregates, random extracellular cross-linking, [[immune system]] decline, and [[endocrine]] changes. Eliminating aging would require finding a solution to each of these causes, a program de Grey calls [[Strategies for engineered negligible senescence|engineered negligible senescence]]. There is also a huge body of knowledge indicating that change is characterized by the loss of molecular fidelity.<ref>{{cite book |last1=Bernstein |first1=C. |last2=Bernstein |first2=H. |year=1991 |title=Aging, Sex, and DNA Repair |publisher=Academic Press |place=San Diego, CA |isbn=978-0120928606}} {{ISBN|0120928604}}</ref>\n\n Disease is theoretically surmountable by technology. In short, it is an abnormal condition affecting the body of an organism, something the body shouldn't typically have to deal with its natural make up.<ref>{{cite web |title=Classification of diseases functioning and disability |date=23 July 2021 |url=https://www.cdc.gov/nchs/icd.htm}}</ref> Human understanding of [[genetics]] is leading to cures and treatments for a myriad of previously incurable diseases. The mechanisms by which other diseases do damage are becoming better understood. Sophisticated methods of detecting diseases early are being developed. [[Preventative medicine]] is becoming better understood. Neurodegenerative diseases like [[Parkinson's disease|Parkinson's]] and [[Alzheimer's disease|Alzheimer's]] may soon be curable with the use of [[stem cells]]. Breakthroughs in [[cell biology]] and [[telomere]] research are leading to treatments for cancer. [[Vaccine]]s are being researched for AIDS and [[tuberculosis]]. Genes associated with [[type 1 diabetes]] and certain types of cancer have been discovered, allowing for new therapies to be developed. Artificial devices attached directly to the [[nervous system]] may restore sight to the blind. Drugs are being developed to treat a myriad of other diseases and ailments.\n\n [[Physical trauma]] would remain as a threat to perpetual physical life, as an otherwise immortal person would still be subject to unforeseen accidents or catastrophes. The speed and quality of [[paramedic]] [[disaster relief operation|response]] remains a determining factor in surviving severe trauma.<ref name=walker>{{cite book |last=Walker |first=Peter |date=1991 |title=International Search and Rescue Teams |series=League Discussion Paper |publisher=[[IFRC|League of the Red Cross and Red Crescent Societies]] |place=Geneva, CH}}</ref> A body that could automatically repair itself from severe trauma, such as speculated uses for [[nanotechnology]], would mitigate this factor. The brain cannot be risked to trauma if a continuous physical life is to be maintained. This aversion to trauma risk to the brain would naturally result in significant behavioral changes that would render physical immortality undesirable for some people.\n\n Organisms otherwise unaffected by these causes of death would still face the problem of obtaining sustenance (whether from currently available agricultural processes or from hypothetical future technological processes) in the face of changing availability of suitable resources as environmental conditions change. After avoiding aging, disease, and trauma, death through resource limitation is still possible, such as [[Hypoxia (medical)|hypoxia]] or [[starvation]].\n\nIf there is no limitation on the degree of gradual mitigation of risk then it is possible that the [[cumulative probability]] of death over an infinite horizon is less than [[certainty]], even when the risk of fatal trauma [[Hazard rate|in any finite period]] is greater than zero. Mathematically, this is an aspect of achieving [[Indefinite lifespan#Actuarial escape velocity|\u2018actuarial escape velocity\u2019]].\n\n [[File:Telomere caps.gif|thumb|right|Human [[chromosome]]s (grey) capped by telomeres (white)]]\n{{Main|Biological immortality}}\n\nBiological immortality is an absence of aging. Specifically it is the absence of a sustained increase in [[rate of mortality]] as a function of chronological age. A cell or organism that does not experience aging, or ceases to age at some point, is biologically immortal.<ref>{{cite web|url=http://www.immortality.foundation/aging|title=What is Aging?|access-date=6 November 2020}}</ref>\n\n[[Biologist]]s have chosen the word "immortal" to designate cells that are not limited by the [[Hayflick limit]], where cells no longer divide because of [[DNA repair|DNA damage]] or shortened [[telomere]]s. The first and still most widely used immortal cell line is [[HeLa]], developed from cells taken from the malignant cervical tumor of [[Henrietta Lacks]] without her consent in 1951. Prior to the 1961 work of [[Leonard Hayflick]], there was the erroneous belief fostered by [[Alexis Carrel]] that all normal [[Somatic (biology)|somatic]] cells are immortal. By preventing cells from reaching senescence one can achieve biological immortality; telomeres, a "cap" at the end of DNA, are thought to be the cause of cell aging. Every time a cell divides the telomere becomes a bit shorter; when it is finally worn down, the cell is unable to split and dies. [[Telomerase]] is an enzyme which rebuilds the telomeres in stem cells and cancer cells, allowing them to replicate an infinite number of times.<ref name="LinKahWai">{{cite journal |author=Lin Kah Wai |author-link=Lin Kah Wai |title=Telomeres, Telomerase, and Tumorigenesis \u2013 A Review |journal=MedGenMed |date=18 April 2004 |volume=6 |issue=3 |page=19 |pmid=15520642 |pmc=1435592}}</ref> No definitive work has yet demonstrated that telomerase can be used in human somatic cells to prevent healthy tissues from aging. On the other hand, scientists hope to be able to grow organs with the help of stem cells, allowing organ transplants without the risk of rejection, another step in extending human life expectancy. These technologies are the subject of ongoing research, and are not yet realized.<ref>{{cite news|url=https://www.nytimes.com/2017/01/26/science/chimera-stemcells-organs.html|title=New Prospects for Growing Human Replacement Organs in Animals|website=nytimes.com|access-date=3 March 2018}}</ref>\n\n {{see also|List of longest-living organisms}}\n\nLife defined as biologically immortal is still susceptible to causes of death besides aging, including disease and trauma, as defined above. Notable immortal species include:\n* ''Bacteria'' \u2013 Bacteria reproduce through [[Fission (biology)|binary fission]]. A parent bacterium splits itself into two identical daughter cells which eventually then split themselves in half. This process repeats, thus making the bacterium essentially immortal. A 2005 [[PLoS Biology]] paper<ref>{{cite web|url= http://hal.archives-ouvertes.fr/docs/00/08/01/54/PDF/stewart_Plos.pdf|title= Aging and Death in an Organism That Reproduces by Morphologically Symmetric Division}}</ref> suggests that after each division the daughter cells can be identified as the older and the younger, and the older is slightly smaller, weaker, and more likely to die than the younger.<ref>{{cite web |url=https://www.newscientist.com/channel/health/mg18524855.800-bacteria-death-reduces-human-hopes-of-immortality.html |title=Bacteria Death Reduces Human Hopes of Immortality |date=5 February 2005 |website=New Scientist magazine, issue 2485| page= 19 |access-date=2 April 2007}}</ref>\n* ''[[Turritopsis dohrnii]]'', a jellyfish (phylum [[Cnidaria]], class [[Hydrozoa]], order [[Anthoathecata]]), after becoming a sexually mature adult, can transform itself back into a [[polyp (zoology)|polyp]] using the cell conversion process of [[transdifferentiation]].<ref name="CheatingDeath">{{cite web|url=http://10e.devbio.com/article.php?ch=2&id=6|title=Cheating Death: The Immortal Life Cycle of Turritopsis|last=Gilbert|first=Scott F.|date=2006|access-date=14 June 2009|url-status=dead|archive-url=https://web.archive.org/web/20151121052612/http://10e.devbio.com/article.php?ch=2&id=6|archive-date=21 November 2015}}</ref> ''Turritopsis dohrnii'' repeats this cycle, meaning that it may have an [[indefinite lifespan]].<ref name="CheatingDeath" /> Its immortal adaptation has allowed it to spread from its original habitat in the Caribbean to "all over the world".<ref name="Telegraph-immortal-jellyfish">{{cite news |url=https://www.telegraph.co.uk/earth/wildlife/4357829/Immortal-jellyfish-swarming-across-the-world.html |archive-url=https://web.archive.org/web/20090130115250/http://www.telegraph.co.uk/earth/wildlife/4357829/Immortal-jellyfish-swarming-across-the-world.html |url-status=dead |archive-date=30 January 2009 |title={{-'}}Immortal' jellyfish swarming across the world |date=30 January 2009 |publisher=[[Telegraph Media Group]] |access-date= 14 June 2009 |location=London}}</ref><ref>{{cite web|url=http://news.nationalgeographic.com/news/2009/01/090130-immortal-jellyfish-swarm.html|title="Immortal" Jellyfish Swarm World's Oceans|website=news.nationalgeographic.com|date=29 January 2009|access-date=19 August 2017}}</ref>\n* ''[[Hydra (genus)|Hydra]]'' is a [[genus]] belonging to the phylum [[Cnidaria]], the class [[Hydrozoa]] and the order [[Anthomedusae]]. They are simple fresh-water [[predatory]] animals possessing [[symmetry (biology)#Radial symmetry|radial symmetry]].<ref>Gilberson, Lance, ''Zoology Lab Manual'', 4th edition. Primis Custom Publishing. 1999.</ref><ref>{{Cite news|url=https://www.livescience.com/53178-hydra-may-live-forever.html|title=Hail the Hydra, an Animal That May Be Immortal|work=Live Science|access-date=19 August 2017}}</ref>\n* ''[[Bristlecone pine]]s'' are speculated to be potentially immortal;{{Citation needed|date=January 2010}} the oldest known living specimen is over 5,000 years old.\n\n {{Main|Evolution of aging}}<!--that's how they spell aging in England ... and in that article-->\nAs the existence of biologically immortal species demonstrates, there is no [[second law of thermodynamics|thermodynamic]] necessity for senescence: a defining feature of life is that it takes in [[Gibbs free energy|free energy]] from the environment and unloads its [[entropy]] as waste. Living systems can even build themselves up from seed, and routinely repair themselves. Aging is therefore presumed to be a byproduct of [[evolution]], but why mortality should be selected for remains a subject of research and debate. Programmed cell death and the telomere "end replication problem" are found even in the earliest and simplest of organisms.<ref>Clark, W.R. 1999. ''A Means to an End: The biological basis of aging and death.'' New York: Oxford University Press. {{cite web |url=http://wrclarkbooks.com/means_to_an_end.html |title=Archived copy |access-date=25 May 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080511212036/http://www.wrclarkbooks.com/means_to_an_end.html |archive-date=11 May 2008 }} About telomeres and programmed cell death.</ref> This may be a tradeoff between selecting for cancer and selecting for aging.<ref>Harrison's ''Principles of Internal Medicine'', Ch. 69, "Cancer cell biology and angiogenesis", Robert G. Fenton and Dan L. Longo, p. 454.</ref>\n\nModern theories on the evolution of aging include the following:\n* Mutation accumulation is a theory formulated by [[Peter Medawar]] in 1952 to explain how evolution would select for aging. Essentially, aging is never selected against, as organisms have offspring before the mortal mutations surface in an individual.\n* [[Pleiotropy|Antagonistic pleiotropy]] is a theory proposed as an alternative by [[George C. Williams (biologist)|George C. Williams]], a critic of Medawar, in 1957. In antagonistic pleiotropy, genes carry effects that are both beneficial and detrimental. In essence this refers to genes that offer benefits early in life, but exact a cost later on, i.e. decline and death.<ref>Williams, G.C. 1957. Pleiotropy, natural selection and the evolution of senescence. ''Evolution'', '''11''':398\u2013411. {{cite web|url=http://www.telomere.org/Downloads/Williams_searchable.pdf |title=Archived copy |access-date=23 July 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060713071204/http://www.telomere.org/Downloads/Williams_searchable.pdf |archive-date=13 July 2006 }} Paper in which Williams describes his theory of antagonistic pleiotropy.</ref>\n* The disposable soma theory was proposed in 1977 by [[Tom Kirkwood|Thomas Kirkwood]], which states that an individual body must allocate energy for metabolism, reproduction, and maintenance, and must compromise when there is food scarcity. Compromise in allocating energy to the repair function is what causes the body gradually to deteriorate with age, according to Kirkwood.<ref>Kirkwood, T.B.L. 1977. Evolution of aging. ''Nature'', '''270''': 301\u2013304. [http://www.nature.com/nature/journal/v270/n5635/abs/270301a0.html] Origin of the disposable soma theory.</ref>\n\n \nIndividual organisms ordinarily age and die, while the germlines which connect successive generations are potentially immortal. The basis for this difference is a fundamental problem in biology.   The Russian biologist and historian [[Zhores A. Medvedev]]<ref name="Medvedev1981">{{cite journal |last=Medvedev |first=Zhores A. |title=On the immortality of the germ line: Genetic and biochemical mechanisms. A review |journal=Mechanisms of Ageing and Development |volume=17 |issue=4 |year=1981 |pages=331\u2013359 |issn=0047-6374 |doi=10.1016/0047-6374(81)90052-X|pmid=6173551 |s2cid=35719466 }}</ref> considered that the accuracy of [[genome]] replicative and other synthetic systems alone cannot explain the immortality of [[germ line]]s. Rather Medvedev thought that known features of the biochemistry and genetics of [[sexual reproduction]] indicate the presence of unique information maintenance and restoration processes at the different stages of [[gametogenesis]]. In particular, Medvedev considered that the most important opportunities for information maintenance of [[germ cell]]s are created by [[genetic recombination|recombination during meiosis]] and [[DNA repair]]; he saw these as processes within the germ cells that were capable of restoring the integrity of [[DNA]] and [[chromosome]]s from the types of damage that cause irreversible aging in [[somatic cell]]s.\n\n \n Some{{who|date=July 2021}} scientists believe that boosting the amount or proportion of [[telomerase]] in the body, a naturally forming enzyme that helps maintain the protective caps at the ends of [[chromosome]]s, could prevent cells from dying and so may ultimately lead to extended, healthier lifespans. A team of researchers at the Spanish National Cancer Centre ([[Madrid]]) tested the hypothesis on mice. It was found that those mice which were "[[genetic engineering|genetically engineered]] to produce 10 times the normal levels of telomerase lived 50% longer than normal mice".<ref>{{cite news |url=https://www.telegraph.co.uk/health/healthnews/3489881/Scientists-take-a-step-closer-to-an-elixir-of-youth.html |archive-url=https://web.archive.org/web/20081201081233/http://www.telegraph.co.uk/health/healthnews/3489881/Scientists-take-a-step-closer-to-an-elixir-of-youth.html |url-status=dead |archive-date=1 December 2008 |work=The Daily Telegraph |location=London |title=Scientists take a step closer to an elixir of youth |first=Richard |last=Alleyne |date=20 November 2008 |access-date=5 May 2010}}</ref>\n\nIn normal circumstances, without the presence of telomerase, if a cell divides repeatedly, at some point all the progeny will reach their [[Hayflick limit]]. With the presence of telomerase, each dividing cell can replace the lost bit of [[DNA]], and any single cell can then divide unbounded. While this unbounded growth property has excited many researchers, caution is warranted in exploiting this property, as exactly this same unbounded growth is a crucial step in enabling cancerous growth. If an organism can replicate its body cells faster, then it would theoretically stop aging.\n\n[[Embryonic stem cells]] express telomerase, which allows them to divide repeatedly and form the individual. In adults, telomerase is highly expressed in cells that need to divide regularly (e.g., in the immune system), whereas most [[Somatic (biology)|somatic]] cells express it only at very low levels in a cell-cycle dependent manner.\n\n {{Main|Molecular machine}}\n\nTechnological immortality is the prospect for much longer life spans made possible by scientific advances in a variety of fields: nanotechnology, emergency room procedures, genetics, [[biological engineering]], [[regenerative medicine]], [[microbiology]], and others. Contemporary life spans in the advanced industrial societies are already markedly longer than those of the past because of better nutrition, availability of health care, standard of living and bio-medical scientific advances.{{citation needed|date=October 2021}} Technological immortality predicts further progress for the same reasons over the near term. An important aspect of current scientific thinking about immortality is that some combination of [[human cloning]], cryonics or nanotechnology will play an essential role in extreme life extension. [[Robert Freitas]], a nanorobotics theorist, suggests tiny medical [[nanorobot]]s could be created to go through human bloodstreams, find dangerous things like cancer cells and bacteria, and destroy them.<ref>Robert A. Freitas Jr., ''Microbivores: Artificial Mechanical Phagocytes using Digest and Discharge Protocol'', self-published, 2001 [http://www.rfreitas.com/Nano/Microbivores.htm]</ref> Freitas anticipates that gene-therapies and nanotechnology will eventually make the human body effectively self-sustainable and capable of living indefinitely in empty space, short of severe brain trauma. This supports the theory that we will be able to continually create biological or synthetic replacement parts to replace damaged or dying ones. Future advances in [[nanomedicine]] could give rise to [[life extension#Nanotechnology|life extension]] through the repair of many processes thought to be responsible for aging. [[K. Eric Drexler]], one of the founders of [[nanotechnology]], postulated cell repair devices, including ones operating within cells and using as yet hypothetical [[biological machine]]s, in his 1986 book [[Engines of Creation]]. [[Raymond Kurzweil]], a [[futurist]] and [[transhumanist]], stated in his book ''[[The Singularity Is Near]]'' that he believes that advanced medical [[nanorobotics]] could completely remedy the effects of aging by 2030.<ref>{{Cite book |first=Ray |last=Kurzweil |author-link=Raymond Kurzweil |year=2005 |title=The Singularity Is Near |publisher=[[Viking Press]] |location=New York City |isbn=978-0-670-03384-3 |oclc=57201348|title-link=The Singularity Is Near }}{{Page needed|date=September 2010}}</ref> According to [[Richard Feynman]], it was his former graduate student and collaborator [[Albert Hibbs]] who originally suggested to him (circa 1959) the idea of a ''medical'' use for Feynman's theoretical micromachines (see [[biological machine]]). Hibbs suggested that certain repair machines might one day be reduced in size to the point that it would, in theory, be possible to (as Feynman put it) "swallow the doctor". The idea was incorporated into Feynman's 1959 essay ''[[There's Plenty of Room at the Bottom]].''<ref>{{cite web\n |url=http://www.its.caltech.edu/~feynman/plenty.html\n |title=There's Plenty of Room at the Bottom\n |author=Richard P. Feynman\n |date=December 1959\n |access-date=1 March 2010\n|url-status=dead\n |archive-url=https://web.archive.org/web/20100211190050/http://www.its.caltech.edu/~feynman/plenty.html\n |archive-date=11 February 2010\n}}</ref>\n\n {{Main|Cryonics}}\n\n[[Cryonics]], the practice of preserving organisms (either intact specimens or only their brains) for possible future revival by storing them at cryogenic temperatures where metabolism and decay are almost completely stopped, can be used to 'pause' for those who believe that life extension technologies will not develop sufficiently within their lifetime. Ideally, cryonics would allow clinically dead people to be brought back in the future after cures to the patients' diseases have been discovered and [[rejuvenation (aging)|aging is reversible]]. Modern cryonics procedures use a process called [[Cryopreservation#Vitrification|vitrification]] which creates a glass-like state rather than [[freezing]] as the body is brought to low temperatures. This process reduces the risk of ice crystals damaging the cell-structure, which would be especially detrimental to cell structures in the brain, as their minute adjustment evokes the individual's mind.\n\n {{Main|Mind uploading}}\n\nOne idea that has been advanced involves [[Mind uploading|uploading]] an individual's habits and memories via [[direct mind-computer interface]]. The individual's memory may be loaded to a computer or to a new organic body. [[Extropian]] [[futures studies|futurists]] like Moravec and [[Ray Kurzweil|Kurzweil]] have proposed that, thanks to [[exponential growth|exponentially growing]] computing power, it will someday be possible to [[mind uploading|upload human consciousness]] onto a computer system, and exist indefinitely in a virtual environment.\n\nThis could be accomplished via advanced cybernetics, where computer hardware would initially be installed in the brain to help sort memory or accelerate thought processes. Components would be added gradually until the person's entire brain functions were handled by artificial devices, avoiding sharp transitions that would lead to issues of [[identity (social science)|identity]], thus running the risk of the person to be declared dead and thus not be a legitimate owner of his or her property. After this point, the human body could be treated as an optional accessory and the program implementing the person could be transferred to any sufficiently powerful computer.\n\nAnother possible mechanism for mind upload is to perform a detailed scan of an individual's original, organic brain and simulate the entire structure in a computer. What level of detail such scans and simulations would need to achieve to emulate awareness, and whether the scanning process would destroy the brain, is still to be determined.{{efn|\nThe basic idea is to take a particular brain, scan its structure in detail, and construct a software model of it that is so faithful to the original that, when run on appropriate hardware, it will behave in essentially the same way as the original brain.\n::: \u2014 Sandberg & Bostr\u00f6m (2008)<ref name=Sandberg-Bostr\u00f6m-2008-Roadmap>\n{{cite book\n |last1=Sandberg |first1= Anders\n |last2=Bostr\u00f6m  |first2=Nick \n |year=2008\n |title=Whole Brain Emulation: A roadmap\n |series=Technical Report\n |volume=#2008-3\n |publisher=Oxford University\n |department=Future of Humanity Institute\n |url=http://www.fhi.ox.ac.uk/Reports/2008-3.pdf\n |access-date=5 April 2009\n}}\n</ref>\n}}\n\nIt is suggested that achieving immortality through this mechanism would require specific consideration to be given to the role of [[consciousness]] in the functions of the [[mind]]. An uploaded mind would only be a copy of the original mind, and not the conscious mind of the living entity associated in such a transfer. Without a simultaneous upload of consciousness, the original living entity remains mortal, thus not achieving true immortality.<ref>\n{{cite web\n |last=Ruparel |first=Bhavik\n |date=30 July 2018\n |title=On achieving immortality\n |website=Iva.to\n |url=https://medium.com/iva-to/on-achieving-immortality-3ed1d567f7a2\n |access-date=10 September 2018\n}}\n</ref>\nResearch on [[neural correlates of consciousness]] is yet inconclusive on this issue. Whatever the route to mind upload, persons in this state could then be considered essentially immortal, short of loss or traumatic destruction of the machines that maintained them.{{clarify|date=October 2015}}{{citation needed|date=September 2021}}\n\n {{Main|Cyborg}}\n\nTransforming a human into a [[cyborg]] can include [[brain implants]] or extracting a human processing unit and placing it in a robotic life-support system.{{citation needed|date=January 2021}} Even replacing biological organs with robotic ones could increase life span (e.g. pace makers) and depending on the definition, many technological upgrades to the body, like genetic modifications or the addition of nanobots would qualify an individual as a cyborg. Some people believe that such modifications would make one impervious to aging and disease and theoretically immortal unless killed or destroyed.{{citation needed|date=January 2021}}\n\n {{Main|Digital immortality}}", "Immortality --- Introduction ---|Religious views": "{{Main|Afterlife|Soul}}\nAs late as 1952, the editorial staff of the ''[[A Syntopicon: An Index to The Great Ideas|Syntopicon]]'' found in their compilation of the [[Great Books of the Western World]], that "The philosophical issue concerning immortality cannot be separated from issues concerning the existence and nature of man's soul."<ref name="Syntopicon I 788">{{cite book |title=The Great Ideas: A Syntopicon of Great Books of the Western World |author=Adler, Mortimer J., ed. |author-link=Mortimer Adler |display-authors=etal |date=1952 |page=788 |publisher=Encyclop\u00e6dia Britannica |location=Chicago|title-link=Syntopicon }}</ref> Thus, the vast majority of speculation on immortality before the 21st century was regarding the nature of the [[afterlife]].\n\n Immortality in [[ancient Greek religion]] originally always included an eternal union of body and soul as can be seen in [[Homer]], [[Hesiod]], and various other ancient texts. The soul was considered to have an eternal existence in Hades, but without the body the soul was considered dead. Although almost everybody had nothing to look forward to but an eternal existence as a disembodied dead soul, a number of men and women were considered to have gained physical immortality and been brought to live forever in either [[Elysium]], the [[Islands of the Blessed]], heaven, the ocean or literally right under the ground.\nAmong those humans made immortal were [[Amphiaraus]], [[Ganymede (mythology)|Ganymede]], [[Ino (Greek mythology)|Ino]], [[Iphigenia]], [[Menelaus]], [[Peleus]], and a great number of those who fought in the Trojan and Theban wars.\n\nSome were considered to have died and been resurrected before they achieved physical immortality. [[Asclepius]] was killed by Zeus only to be resurrected and transformed into a major deity. In some versions of the [[Trojan War]] myth, [[Achilles]], after being killed, was snatched from his funeral pyre by his divine mother [[Thetis]], resurrected, and brought to an immortal existence in either [[Leuce (mythology)|Leuce]], the Elysian plains, or the Islands of the Blessed. [[Memnon (mythology)|Memnon]], who was killed by Achilles, seems to have received a similar fate. [[Alcmene]], [[Castor and Pollux|Castor]], [[Heracles]], and [[Melicertes]] were also among the figures sometimes considered to have been resurrected to physical immortality.{{sfn|Endsj\u00f8|2009|pp=54\u201370}} According to [[Histories (Herodotus)|Herodotus' Histories]], the 7th century {{sc|BCe}} sage [[Aristeas of Proconnesus]] was first found dead, after which his body disappeared from a locked room. Later he was found not only to have been resurrected but to have gained immortality.\n\nThe parallel between these traditional beliefs and the later resurrection of Jesus was not lost on early Christians, as [[Justin Martyr]] argued:\n: "when we say ... Jesus Christ, our teacher, was crucified and died, and rose again, and ascended into heaven, we propose nothing different from what you believe regarding those whom you consider sons of Zeus."<ref>{{cite book |author=[[Justin Martyr]] |title=First Apology |at=21}}</ref>\n\nThe philosophical idea of an [[immortal soul]] was a belief first appearing with either [[Pherecydes of Syros|Pherecydes]] or the [[Orphics]], and most importantly advocated by [[Plato]] and his followers. This, however, never became the general norm in Hellenistic thought. As may be witnessed even into the Christian era, not least by the complaints of various philosophers over popular beliefs, many or perhaps most traditional Greeks maintained the conviction that certain individuals were resurrected from the dead and made physically immortal and that others could only look forward to an existence as disembodied and dead, though everlasting, souls.{{sfn|Rohde|1925}}\n\n {{Expand section|date=June 2019}}\nOne of the three marks of existence in Buddhism is [[anatt\u0101]], "non-self". This teaching states that the body does not have an eternal soul but is composed of five [[skandhas]] or aggregates. Additionally, another mark of existence is impermanence, also called [[anicca]], which runs directly counter to concepts of immortality or permanence. According to one [[Tibetan Buddhist]] teaching, [[Dzogchen]], individuals can transform the physical body into an immortal body of light called the [[rainbow body]].{{citation needed|date=June 2019}}\n\n {{main|Eternal life (Christianity)|Christian conditionalism|Christian mortalism|Universal resurrection}}\n[[File:Holbein Danse Macabre 3.jpg|thumb|Adam and Eve condemned to mortality. [[Hans Holbein the Younger]], ''Danse Macabre'', 16th century]]\n\n[[Christianity|Christian theology]] holds that [[Adam and Eve]] lost physical immortality for themselves and all their descendants in the [[Fall of man]], although this initial "imperishability of the bodily frame of man" was "a preternatural condition".<ref name="Syntopicon I 784">{{cite book |title=The Great Ideas: A Syntopicon of Great Books of the Western World |author=Adler, Mortimer J., ed. |author-link=Mortimer Adler |display-authors=etal |date=1952 |page=784 |publisher=Encyclop\u00e6dia Britannica |location=Chicago|title-link=Syntopicon }}</ref>\n\nChristians who profess the [[Nicene Creed]] believe that every dead person (whether they believed in Christ or not) will be resurrected from the dead at the [[Second Coming]], and this belief is known as [[Universal resurrection]].{{sfn|Perkins|1984|pp=17\u201318}} While [[Paul the Apostle]] insisted that the resurrected body was only "spiritual"<ref>1. Cor. 15.44</ref> and that "flesh and blood cannot inherit the kingdom of God".,<ref>1. Cor. 15.50</ref>{{sfn|af H\u00e4llstr\u00f6m|1988|p=10}} the Gospels increasingly emphasized the physical nature of the resurrection body \u2013 as the resurrected Jesus in the [[Gospel of Luke]] insisting on his still consisting of "flesh and bones".<ref>Luke 24.37.</ref> This shift may have been in response to [[Ancient Greek religion|traditional Greek]] expectations that immortality always included both body and soul.{{sfn|Endsj\u00f8|2009|pp=141\u201358}}\n\n[[N.T. Wright]], a theologian and former [[Bishop of Durham]], has said many people forget the physical aspect of what Jesus promised. He told [[Time (magazine)|Time]]: "Jesus' resurrection marks the beginning of a restoration that he will complete upon [[Second Coming of Christ|his return]]. Part of this will be the [[Universal resurrection|resurrection of all the dead]], who will 'awake', be embodied and participate in the renewal. Wright says [[John Polkinghorne]], a physicist and a priest, has put it this way: 'God will download our software onto his hardware until the time he gives us new hardware to run the software again for ourselves.' That gets to two things nicely: that the period after death (the [[Intermediate state]]) is a period when we are in God's presence but not active in our own bodies, and also that the more important transformation will be when we are again embodied and administering [[World to Come|Christ's kingdom]]."<ref>{{cite news |url=http://www.time.com/time/world/article/0,8599,1710844,00.html|work=Time |title=Christians Wrong About Heaven, Says Bishop |date=7 February 2008 |access-date=5 May 2010 |first=David |last=Van Biema|url-status=dead|archive-url=https://web.archive.org/web/20080209101034/http://www.time.com/time/world/article/0,8599,1710844,00.html |archive-date=9 February 2008 }}</ref> This kingdom will consist of [[World to Come|Heaven and Earth "joined together in a new creation"]], he said.\n\nChristian apocrypha include immortal human figures such as [[Cartaphilus]]<ref>{{Cite book|last1=Wendover|first1=Roger of|title=Roger of Wendover's Flowers of history, Comprising the history of England from the descent of the Saxons to A.D. 1235; formerly ascribed to Matthew Paris.|series=Bohn's antiquarian library|date=1849|publisher=London|hdl=2027/yale.39002013002903}}</ref> and [[Longinus]]<ref>Ehrman, Bart D, and Zlatko Ple\u0161e. ''The Apocryphal Gospels: Texts and Translations''. New York: Oxford University Press, 2011, p. 523</ref> who were cursed with physical immortality for various transgressions against Christ during the Passion.\n\n {{See also|Chiranjivi|Naraka (Hinduism)}}\n[[File:Reincarnation AS.jpg|thumb|Representation of a soul undergoing ''[[Reincarnation|punarjanma]]''. Illustration from ''Hinduism Today'', 2004]]\n\n[[Hinduism|Hindus]] believe in an immortal soul which is [[Reincarnation|reincarnated]] after death. According to Hinduism, people repeat a process of life, death, and rebirth in a cycle called ''[[samsara]]''. If they live their life well, their ''[[karma]]'' improves and their station in the next life will be higher, and conversely lower if they live their life poorly. After many life times of perfecting its karma, the soul is freed from the cycle and lives in perpetual bliss.  There is no place of eternal torment in Hinduism, although if a soul consistently lives very evil lives, it could work its way down to the very bottom of the cycle.{{citation needed|date=June 2015}}\n\nThere are explicit renderings in the [[Upanishad]]s alluding to a physically immortal state brought about by purification, and sublimation of the 5 elements that make up the body. For example, in the [[Shvetashvatara Upanishad]] (Chapter 2, Verse 12), it is stated "When earth, water, fire, air and sky arise, that is to say, when the five attributes of the elements, mentioned in the books on yoga, become manifest then the yogi's body becomes purified by the fire of yoga and he is free from illness, old age and death."\n\nAnother view of immortality is traced to the Vedic tradition by the interpretation of [[Maharishi Mahesh Yogi]]:\n<blockquote>\nThat man indeed whom these (contacts)<br>do not disturb, who is even-minded in<br>pleasure and pain, steadfast, he is fit<br>for immortality, O best of men.<ref name="Maharishi-Mahesh-Yogi">Maharishi Mahesh Yogi on the Bhagavad-Gita, a New Translation and Commentary, Chapter 1\u20136. Penguin Books, 1969, pp. 94\u201395 (v 15)</ref></blockquote>\n\nTo Maharishi Mahesh Yogi, the verse means, "Once a man has become established in the understanding of the permanent reality of life, his mind rises above the influence of pleasure and pain. Such an unshakable man passes beyond the influence of death and in the permanent phase of life: he attains eternal life ... A man established in the understanding of the unlimited abundance of absolute existence is naturally free from existence of the relative order. This is what gives him the status of immortal life."<ref name="Maharishi-Mahesh-Yogi"/>\n\nAn Indian Tamil saint known as [[Vallalar]] claimed to have achieved immortality before disappearing forever from a locked room in 1874.<ref>{{cite web |url=http://www.vallalar.org |title=vallalar.org |publisher=vallalar.org |date=7 July 2010 |access-date=4 November 2010}}</ref>{{Unreliable source?|date=February 2012}}<ref>{{cite book|title=In the Fabled East: A Novel|url=https://books.google.com/books?id=Y1RgQC-hw1MC&q=Vallalar+immortality+1874&pg=PA174|author=Adam Schroeder|publisher=[[Douglas & McIntyre|D & M Publishers]]|page=174|isbn=978-1553656159|date=6 March 2010}}</ref>\n\n {{primary sources|date=June 2015}}\nThe traditional concept of an immaterial and [[Immortality of the soul|immortal soul]] distinct from the body was not found in Judaism before the [[Babylonian exile]], but developed as a result of interaction with [[Persian philosophy|Persian]] and [[Hellenistic philosophy|Hellenistic philosophies]]. Accordingly, the Hebrew word ''[[nephesh]]'', although translated as ''"soul"'' in some older English-language Bibles, actually has a meaning closer to "living being".<ref>{{cite book |publisher=Biblical Studies Press |year=2006 |title=New English Translation |section=Notes |at=Note 23, for {{bibleverse||Gen|2:7}} }}</ref>{{request quotation|date=February 2020}} ''Nephesh'' was rendered in the [[Septuagint]] as {{mvar| {{lang|grc|\u03c8\u03c5\u03c7\u03ae}} }} (''ps\u016bch\u00ea''), the Greek word for \u2018soul\u2019.{{citation needed|date=June 2015}}\n\nThe only Hebrew word traditionally translated "soul" (''nephesh'') in English language Bibles refers to a living, breathing conscious body, rather than to an immortal soul.{{efn|\n"Even as we are conscious of the broad and very common biblical usage of the term ''"soul"'', we must be clear that scripture does not present even a rudimentarily developed theology of the soul. The creation narrative is clear that all life originates with God. Yet the Hebrew scripture offers no specific understanding of the origin of individual souls, of when and how they become attached to specific bodies, or of their potential existence, apart from the body, after death. The reason for this is that, as we noted at the beginning, the Hebrew Bible does not present a theory of the soul developed much beyond the simple concept of a force associated with respiration, hence, a life-force."<ref>\n{{cite encyclopedia \n |last = Avery-Peck  |first = Alan J.\n |year = 2000\n |title = Soul\n |editor = Neusner\n |display-editors = etal \n |encyclopedia = The Encyclopedia of Judaism\n |page=1343\n}}\n</ref>{{full citation needed|date=September 2021|reason=full editors' names, publisher, etc.; ISBN would be nice}}\n}}\nIn the New Testament, the Greek word traditionally translated "soul" ({{lang|grc|\u03c8\u03c5\u03c7\u03ae}}) has substantially the same meaning as the Hebrew, without reference to an immortal soul.{{efn|\nIn the ''[[New Testament]]'', "soul" (orig. {{mvar| {{lang|grc|\u03c8\u03c5\u03c7\u03ae}} }}) retains its basic Hebrew sense of meaning. "Soul" refers to one\u2019s life: Herod sought Jesus\u2019 ''soul'' ({{bibleverse||Matt.|2:20}}); one might save a ''soul'' or take it ({{bibleverse||Mark|3:4}}); death occurs when God \u201crequires your ''soul''\u201d ({{bibleverse||Luke|12:20}}).\n}}\n''"Soul"'' may refer either to the whole person, the self, as in "three thousand ''souls''" were converted in {{bibleverse||Acts|2:41}} (see {{bibleverse||Acts|3:23}}).\n\nThe [[Hebrew Bible]] speaks about ''[[Sheol]]'' (\u05e9\u05d0\u05d5\u05dc), originally a synonym of the grave \u2013 the repository of the dead or the cessation of existence, until the [[Techiyat hamaysim|resurrection of the dead]]. This doctrine of resurrection is mentioned explicitly only in {{bibleverse||Daniel|12:1\u20134|ESV}} although it may be implied in several other texts. New theories arose concerning Sheol during the [[intertestamental period]].\n\nThe views about immortality in Judaism is perhaps best exemplified by the various references to this in [[Second Temple period]]. The concept of resurrection of the physical body is found in {{nobr|[[2 Maccabees]]}}, according to which it will happen through recreation of the flesh.<ref>{{bibleverse|2|Maccabees|7.11, 28}}</ref> Resurrection of the dead is specified in detail in the extra-canonical books of [[Book of Enoch|Enoch]],<ref>{{cite book |title=1 Enoch |title-link=Book of Enoch |at=61.2, 5}}</ref> and in [[Syriac Apocalypse of Baruch|Apocalypse of Baruch]].<ref>{{cite book |title=2 Baruch |title-link=Syriac Apocalypse of Baruch |at=50.2, 51.5}}</ref> According to the British scholar in ancient Judaism [[Philip R. Davies|P.R. Davies]], there is "little or no clear reference ... either to immortality or to resurrection from the dead" in the [[Dead Sea scrolls]] texts.<ref>\n{{cite book\n |first=P.R. |last=Davies  |author-link=Philip R. Davies\n |year=2000\n |section=Death, resurrection and life after death in the Qumran Scrolls\n |editor1-first=Alan J. |editor1-last=Avery-Peck\n |editor2-first=Jacob   |editor2-last=Neusner\n |title=Judaism in Late Antiquity\n |volume=Part Four: Death, life-after-death, resurrection, and the World-to-Come in the Judaisms of antiquity\n |page=209\n |place=Leiden\n}}\n</ref>\nBoth [[Josephus]] and the [[New Testament]] record that the [[Sadducees]] did not believe in an [[afterlife]],<ref>\n{{cite book |author=[[Josephus]] |title=[[Antiquities of the Jews]] |at=18.16 |postscript=;}}\n{{bibleverse||Matthew|22.23}}; {{bibleverse||Mark|12.18}}; {{bibleverse||Luke|20.27}}; {{bibleverse||Acts|23.8}}\n</ref>\nbut the sources vary on the beliefs of the [[Pharisees]]. The New Testament claims that the Pharisees believed in the resurrection, but does not specify whether this included the flesh or not.<ref>{{bibleverse||Acts|23.8}}</ref> According to [[Josephus]], who himself was a Pharisee, the Pharisees held that only the soul was immortal and the souls of good people will be [[reincarnation|reincarnated]] and "pass into other bodies," while "the souls of the wicked will suffer eternal punishment."<ref>\n{{cite book |author=[[Josephus]] |title=[[The Jewish War|Jewish War]] |at=2.8.14 |postscript=;}} cf.<br/>\n{{cite book |author=[[Josephus]] |title=[[Antiquities of the Jews]] |at=8.14\u201315}}\n</ref>\nThe [[Book of Jubilees]] seems to refer to the resurrection of the soul only, or to a more general idea of an immortal soul.<ref>{{cite book |title=[[Book of Jubilees]] |at=23.31}}</ref>\n\n[[Rabbinic Judaism]] claims that the righteous dead will be resurrected in the [[Messianic Age]], with the coming of the [[messiah in Judaism|messiah]]. They will then be granted immortality in a perfect world. The wicked dead, on the other hand, will not be resurrected at all. This is not the only Jewish belief about the afterlife. The [[Tanakh]] is not specific about the afterlife, so there are wide differences in views and explanations among believers.{{citation needed|date=June 2015}}\n\n {{See also|Chinese alchemy|Taoism and death|Xian (Taoism)}}\n\nIt is repeatedly stated in the ''[[L\u00fcshi Chunqiu]]'' that death is unavoidable.<ref>{{cite book|last=Creel|first=Herrlee G.|title=What is Taoism? : and other studies in Chinese cultural history|date=1982|publisher=University of Chicago Press|location=Chicago|isbn=978-0226120478|page=17}}</ref> [[Henri Maspero]] noted that many scholarly works frame Taoism as a school of thought focused on the quest for immortality.<ref>Maspero, Henri. Translated by Frank A. Kierman, Jr. Taoism and Chinese Religion (University of Massachusetts Press, 1981), p. 211.</ref> Isabelle Robinet asserts that Taoism is better understood as a ''way of life'' than as a religion, and that its adherents do not approach or view Taoism the way non-Taoist historians have done.<ref>Robinet, Isabelle. ''Taoism: Growth of a Religion'' (Stanford: Stanford University Press, 1997 [original French 1992]), p. 3\u20134.</ref> In the Tractate of Actions and their Retributions, a traditional teaching, spiritual immortality can be rewarded to people who do a certain amount of good deeds and live a simple, pure life. A list of good deeds and sins are tallied to determine whether or not a mortal is worthy. Spiritual immortality in this definition allows the soul to leave the earthly realms of afterlife and go to pure realms in the Taoist cosmology.<ref>Translated by Legge, James. ''The Texts of Taoism.'' 1962, Dover Press. NY.</ref>\n\n [[Zoroastrian]]s believe that on the fourth day after death, the human soul leaves the body and the body remains as an empty shell. Souls would go to either heaven or hell; these concepts of the afterlife in Zoroastrianism may have influenced Abrahamic religions. The Persian word for "immortal" is associated with the month "Amurdad", meaning "deathless" in Persian, in the [[Iranian calendar]] (near the end of July). The month of Amurdad or [[Ameretat]] is celebrated in Persian culture as ancient Persians believed the "Angel of Immortality" won over the "Angel of Death" in this month.<ref>{{cite web |last=Hoshang |first=J. Bhadha, Dr. |date=nd |title=Effect of wearing cap on Zarathustri Urvaan |website=Zoroastrianism |id=topic 33 |url=http://tenets.zoroastrianism.com/topi33.html |archive-url=https://web.archive.org/web/20170727145155/http://tenets.zoroastrianism.com/topi33.html |archive-date=27 July 2017 }}</ref>"}},
{"article_title": "Molecular engineering", "pageid": "177515", "revid": "1043793833", "timestamp": "2021-09-12T01:29:29Z", "history_paths": [["Molecular engineering --- Introduction ---", "History"]], "categories": ["nanotechnology", "engineering disciplines"], "heading_tree": {"Molecular engineering --- Introduction ---": {"History": {}, "Applications": {"Consumer Products": {}, "[[Energy harvesting|Energy Harvesting]] and [[Energy storage|Storage]]": {}, "Environmental Engineering": {}, "[[Immunotherapy]]": {}, "[[Synthetic biology|Synthetic Biology]]": {}}, "Techniques and instruments used": {"Computational and Theoretical Approaches": {}, "Microscopy": {}, "Molecular Characterization": {}, "Spectroscopy": {}, "Surface Science": {}, "Synthetic Methods": {}, "Other Tools": {}}, "Research / Education": {}, "See also": {"General topics": {}}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Molecular engineering --- Introduction ---|History": "Molecular engineering was first mentioned in the research literature in 1956 by [[Arthur R. von Hippel]], who defined it as "\u2026 a new mode of thinking about engineering problems.  Instead of taking prefabricated materials and trying to devise engineering applications consistent with their macroscopic properties, one builds materials from their atoms and molecules for the purpose at hand."<ref>{{Cite journal|last=von Hippel|first=Arthur R|date=1956|title=Molecular Engineering|jstor=1750067|journal=Science|volume=123|issue=3191|pages=315\u2013317|doi=10.1126/science.123.3191.315|pmid=17774519|bibcode=1956Sci...123..315V}}</ref> This concept was echoed in [[Richard Feynman|Richard Feynman's]] seminal 1959 lecture ''[[There's Plenty of Room at the Bottom]]'', which is widely regarded as giving birth to some of the fundamental ideas of the field of [[nanotechnology]]. In spite of the early introduction of these concepts, it was not until the mid-1980s with the publication of ''[[Engines of Creation|Engines of Creation: The Coming Era of Nanotechnology]]'' by [[K. Eric Drexler|Drexler]] that the modern concepts of nano and molecular-scale science began to grow in the public consciousness.\n\nThe discovery of electrically-conductive properties in [[polyacetylene]] by [[Alan J. Heeger]] in 1977<ref>{{Cite journal|last=Chiang|first=C. K.|date=1977-01-01|title=Electrical Conductivity in Doped Polyacetylene|journal=Physical Review Letters|volume=39|issue=17|pages=1098\u20131101|doi=10.1103/PhysRevLett.39.1098|bibcode=1977PhRvL..39.1098C}}</ref> effectively opened the field of [[organic electronics]], which has proved foundational for many molecular engineering efforts. Design and optimization of these materials has led to a number of innovations including [[OLED|organic light-emitting diodes]] <nowiki/>and [[Organic solar cell|flexible solar cells]]."}},
{"article_title": "Forward-looking infrared", "pageid": "181389", "revid": "1046484769", "timestamp": "2021-09-25T22:58:28Z", "history_paths": [["Forward-looking infrared --- Introduction ---", "History"]], "categories": ["film and video technology", "infrared imaging", "texas instruments", "targeting (warfare)", "military electronics"], "heading_tree": {"Forward-looking infrared --- Introduction ---": {"Design": {}, "Properties": {}, "Etymology": {}, "History": {}, "Uses": {}, "Cost": {}, "Police actions": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Forward-looking infrared --- Introduction ---|History": "In 1956, [[Texas Instruments]] began research on [[infrared]] technology that led to several line scanner contracts and, with the addition of a second scan mirror, the invention of the first forward-looking infrared camera in 1963, with production beginning in 1966. In 1972, TI invented the Common Module concept, greatly reducing cost and allowing reuse of common components."}},
{"article_title": "Cave painting", "pageid": "182028", "revid": "1059802339", "timestamp": "2021-12-11T18:35:08Z", "history_paths": [["Cave painting --- Introduction ---"], ["Cave painting --- Introduction ---", "Dating"], ["Cave painting --- Introduction ---", "Subjects, themes, and patterns in cave painting"], ["Cave painting --- Introduction ---", "Paleolithic cave art by region"], ["Cave painting --- Introduction ---", "Holocene cave art"]], "categories": ["art of the upper paleolithic", "cave paintings", "indigenous art", "mass media technology", "murals", "pre-columbian art"], "heading_tree": {"Cave painting --- Introduction ---": {"Dating": {}, "Subjects, themes, and patterns in cave painting": {"Theories and interpretations": {}}, "Paleolithic cave art by region": {"Europe": {}, "East and Southeast Asia": {}, "India": {}, "Southern Africa": {}, "Australia": {}}, "Holocene cave art": {"Asia": {}, "Horn of Africa": {}, "North Africa": {}, "Southern Africa": {}, "North America": {}, "South America": {}, "Southeast Asia": {}}, "See also": {}, "Notes": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Cave painting --- Introduction ---": "{{short description|Paintings, often prehistoric, on cave walls and ceilings}}\n[[File:SantaCruz-CuevaManos-P2210651b.jpg|thumb|upright=1.5|[[Cueva de las Manos]], [[Perito Moreno, Santa Cruz|Perito Moreno]], [[Argentina]]. The art in the cave is dated between 7,300 BC and 700 AD,{{Efn|The UNESCO dates the art to 13,000\u20139,000 [[Before Present|BP]].<ref>{{Cite book |title=World Heritage Sites: a Complete Guide to 1007 UNESCO World Heritage Sites |date=2014 |publisher=[[UNESCO Publishing]] |isbn=978-1-77085-640-0 |edition=6th |page=607 |oclc=910986576}}</ref><ref>{{Cite web |last=UNESCO World Heritage Centre |title=Cueva de las Manos, R\u00edo Pinturas |url=https://whc.unesco.org/en/list/936/ |url-status=live |access-date=2021-04-07 |website=UNESCO World Heritage Centre |language=en |archive-date=2021-04-14 |archive-url=https://web.archive.org/web/20210414171517/https://whc.unesco.org/en/list/936}}</ref>|name=UNESCO}} stenciled, mostly left hands are shown.<ref>{{Cite book |url=https://www.worldcat.org/oclc/865298990 |title=Art & Place: Site-Specific Art of the Americas. |date=2013 |publisher=[[Phaidon Press]] |others=Editorial Director: Amanda Renshaw; Text & Expertise provided by Daniel Arsenault et al. |isbn=978-0-7148-6551-5 |pages=354\u2013355 |oclc=865298990 |access-date=2021-03-27 |archive-date=2021-10-29 |archive-url=https://web.archive.org/web/20211029010905/https://www.worldcat.org/wcpa/servlet/org.oclc.lac.ui.ajax.ServiceServlet?serviceCommand=getAllItemReviews&source=goodReads&maxrecords=3&startrecord=1&isbn=9780714865515%25200714865516&oclcNum=865298990 |url-status=live}}</ref><ref name=":9" />]]\n'''Cave paintings''' are a type of [[parietal art]] (which category also includes [[petroglyphs]], or engravings), found on the wall or ceilings of [[cave]]s. The term usually implies [[prehistoric art|prehistoric origin]], and the oldest known are more than 44,000 years old ([[art of the Upper Paleolithic]]), found in both the [[Franco-Cantabrian region]] in western Europe, and in the [[caves in the district of Maros]] ([[Sulawesi]], Indonesia). The oldest are often constructed from hand stencils and simple geometric shapes.<ref name=Aubert2014>M. Aubert et al., "Pleistocene cave art from Sulawesi, Indonesia", ''Nature'' volume 514, pages 223\u2013227 (09 October 2014).\n"using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. In addition, a painting of a [[Babirusa|babirusa (\u2018pig-deer\u2019)]] made at least 35.4 kyr ago is among the earliest dated figurative depictions worldwide, if not the earliest one. Among the implications, it can now be demonstrated that humans were producing rock art by \u223c40 kyr ago at opposite ends of the Pleistocene Eurasian world."</ref> However, more recently, in 2021, cave art of a pig found in an Indonesian island, and dated to over 45,500 years, has been reported.<ref>{{Cite journal|author1-link=Adam Brumm|last1=Brumm|first1=Adam|last2=Oktaviana|first2=Adhi Agus|last3=Burhan|first3=Basran|last4=Hakim|first4=Budianto|last5=Lebe|first5=Rustan|last6=Zhao|first6=Jian-xin|last7=Sulistyarto|first7=Priyatno Hadi|last8=Ririmasse|first8=Marlon|last9=Adhityatama|first9=Shinatria|last10=Sumantri|first10=Iwan|last11=Aubert|first11=Maxime|date=2021-01-01|title=Oldest cave art found in Sulawesi|journal=Science Advances|language=en|volume=7|issue=3|pages=eabd4648|doi=10.1126/sciadv.abd4648|issn=2375-2548|pmid=33523879|pmc=7806210|bibcode=2021SciA....7.4648B|doi-access=free}}</ref><ref name="NYT-20210113">{{cite news |last=Ferreira |first=Becky |title=Pig Painting May Be World's Oldest Cave Art Yet, Archaeologists Say - The depiction of the animal on an Indonesian island is at least 45,500 years old, the researchers say. |url=https://www.nytimes.com/2021/01/13/science/cave-painting-indonesia.html |date=January 13, 2021 |work=[[The New York Times]] |access-date=January 14, 2021 }}</ref>\n\nA 2018 study claimed an age of 64,000 years for the oldest examples of non-figurative cave art in the [[Iberian Peninsula]]. Represented by three red non-figurative symbols found in the caves of [[Cave of Maltravieso|Maltravieso]], Ardales and [[Cave of La Pasiega|La Pasiega]], [[Spain]], these predate the appearance of modern humans in Europe by at least 20,000 years and thus must have been made by [[Neanderthals]] rather than [[European early modern humans|modern humans]].<ref name=Hoffmann2018>. \n{{cite journal |author1=D. L. Hoffmann |author2=C. D. Standish |author3=M. Garc\u00eda-Diez |author4=P. B. Pettitt |author5=J. A. Milton |author6=J. Zilh\u00e3o |author7=J. J. Alcolea-Gonz\u00e1lez |author8=P. Cantalejo-Duarte |author9=H. Collado |author10=R. de Balb\u00edn |author11=M. Lorblanchet |author12=J. Ramos-Mu\u00f1oz |author13=G.-Ch. Weniger |author14=A. W. G. Pike |year=2018 |title=U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art |journal=Science |volume=359 |issue=6378 |pages=912\u2013915 |doi=10.1126/science.aap7778|doi-access=free |pmid=29472483 |bibcode=2018Sci...359..912H }} \n"we present dating results for three sites in Spain that show that cave art emerged in Iberia substantially earlier than previously thought. Uranium-thorium (U-Th) dates on carbonate crusts overlying paintings provide minimum\nages for a red linear motif in La Pasiega (Cantabria), a hand stencil in [[Cave of Maltravieso|Maltravieso (Extremadura)]], and red-painted speleothems in Ardales (Andaluc\u00eda). Collectively, these results show that cave art in Iberia is older than 64.8 thousand years (ka). This cave art is the earliest dated so far and predates, by at least 20 ka, the arrival of modern humans in Europe, which implies Neandertal authorship."</ref>\n\nIn November 2018, scientists reported the discovery of the then-oldest known figurative art painting, over 40,000 (perhaps as old as 52,000) years old, of an unknown animal, in the cave of [[Lubang Jeriji Sal\u00e9h]] on the [[Indonesia]]n island of [[Borneo]].<ref name="NYT-20181107-cz" /><ref name="NAT-20181107" /> In December 2019, however, figurative cave paintings depicting pig hunting in the [[caves in the Maros-Pangkep karst|Maros-Pangkep karst]] in [[Sulawesi]] were estimated to be even older, at least 43,900 years old. The finding was noted to be "the oldest pictorial record of storytelling and the earliest figurative artwork in the world".<ref>{{Cite journal|last=Aubert|first=M.|display-authors=et al.|date=11 December 2019|title=Earliest hunting scene in prehistoric art.|journal=Nature|volume=576|issue=7787|pages=442\u2013445|doi=10.1038/s41586-019-1806-y|pmid=31827284|bibcode=2019Natur.576..442A|s2cid=209311825}}</ref><ref name="NYT-20191211">{{cite news |last=Ferreira |first=Becky |title=Mythical Beings May Be Earliest Imaginative Cave Art by Humans - The paintings on an Indonesian island are at least 43,900 years old and depict humanoid figures with animal-like features in a hunting scene. |url=https://www.nytimes.com/2019/12/11/science/cave-art-indonesia.html |date=11 December 2019 |work=[[The New York Times]] |access-date=12 December 2019 }}</ref>\n\n [[File:Lubang Jeriji Sal\u00e9h cave painting of Bull.jpg|thumb|One of the oldest known [[Figurative art|figurative paintings]], a depiction of an unknown [[Bovinae|bovine]], was discovered in the [[Lubang Jeriji Sal\u00e9h]] cave and dated to be more than 40,000 (perhaps as old as 52,000) years old.<ref name="NYT-20181107-cz" /><ref name="NAT-20181107" />]]\n\nNearly 350 caves have now been discovered in France and Spain that contain art from prehistoric times. Initially, the age of the paintings had been a contentious issue, since methods like [[radiocarbon dating]] can produce misleading results if contaminated by other samples,<ref name=welsh>{{cite book|last=Welsh|first=Liz|title=Rock-art of the Southwest: a Visitor's Companion|year=2000|publisher=Wilderness Press|location=Berkeley, California|isbn=0-89997-258-6|edition=1st|author2=Welsh, Peter|page=62}}</ref> and caves and rocky overhangs (where [[parietal art]] is found) are typically littered with debris from many time periods. But subsequent technology has made it possible to date the paintings by sampling the pigment itself, torch marks on the walls,<ref name=valladas>{{cite journal|last=Valladas|first=Helene|title=Direct radiocarbon dating of prehistoric cave paintings by accelerator mass spectrometry|journal=Measurement Science and Technology|date=1 September 2003|volume=14|issue=9|pages=1487\u20131492|doi=10.1088/0957-0233/14/9/301}}</ref> or the formation of carbonate deposits on top of the paintings.<ref name="Hoffmann, D.L. 2016. pp.104-119">{{cite journal | last1 = Hoffmann | first1 = D.L. | last2 = Pike | first2 = A.W. | last3 = Garc\u00eda-Diez | first3 = M. | last4 = Pettitt | first4 = P.B. | last5 = Zilh\u00e3o | first5 = J. | year = 2016 | title = Methods for U-series dating of CaCO3 crusts associated with Palaeolithic cave art and application to Iberian sites | url = https://eprints.soton.ac.uk/402243/1/Hoffmann%2520et%2520al_accepted.docx| journal = Quaternary Geochronology | volume = 36 | pages = 104\u2013119 | doi = 10.1016/j.quageo.2016.07.004 }}</ref> The subject matter can also indicate chronology: for instance, the [[reindeer]] depicted in the Spanish cave of Cueva de las Monedas places the drawings in the last Ice Age.\n\nThe oldest known cave painting is a red hand stencil in [[Cave of Maltravieso|Maltravieso cave]], [[C\u00e1ceres, Spain|C\u00e1ceres]], Spain. It has been dated using the uranium-thorium method<ref name="Hoffmann, D.L. 2016. pp.104-119"/> to older than 64,000 years and was made by a [[Neanderthal]].<ref name=Hoffmann2018/> The oldest date given to an animal cave painting is now a depiction of several human figures hunting pigs in the [[caves in the Maros-Pangkep karst]] of [[South Sulawesi]], [[Indonesia]], dated to be over 43,900 years old.<ref name="NYT-20191211"/> Before this, the oldest known figurative cave paintings were that of a bull dated to 40,000 years, at [[Lubang Jeriji Sal\u00e9h]] cave, [[East Kalimantan]], [[Borneo]],<ref>Aubert, M. et al [https://www.nature.com/articles/s41586-018-0679-9 Palaeolithic cave art in Borneo] // Nature (2018)</ref> and a depiction of a pig with a minimum age of 35,400 years at Timpuseng cave in Sulawesi.<ref name=Aubert2014/>\n\nThe earliest known European figurative cave paintings are those of [[Chauvet Cave]] in France, dating to earlier than 30,000 BCin the [[Upper Paleolithic]] according to [[radiocarbon]] dating.<ref>{{cite web |last=Clottes |first=Jean |url=http://www.metmuseum.org/toah/hd/chav/hd_chav.htm |title=Chauvet Cave (ca. 30,000 B.C.) |work=Heilbrunn Timeline of Art History |publisher=The Metropolitan Museum of Art |location=New York |date=October 2002 |access-date=11 May 2013}}</ref> Some researchers believe the drawings are too advanced for this era and question this age.<ref>{{cite journal|last=Pettitt|first=Paul|title=Art and the Middle-to-Upper Paleolithic transition in Europe: Comments on the archaeological arguments for an early Upper Paleolithic antiquity of the Grotte Chauvet art|journal=Journal of Human Evolution|date=1 November 2008 |volume=55 |issue=5 |pages=908\u2013917 |doi=10.1016/j.jhevol.2008.04.003 |pmid=18678392}}</ref> However, more than 80 radiocarbon dates had been obtained by 2011, with samples taken from torch marks and from the paintings themselves, as well as from animal bones and charcoal found on the cave floor. The radiocarbon dates from these samples show that there were two periods of creation in Chauvet: 35,000 years ago and 30,000 years ago. One of the surprises was that many of the paintings were modified repeatedly over thousands of years, possibly explaining the confusion about finer paintings that seemed to date earlier than cruder ones.<ref>{{cite journal |last=Zorich |first=Zach |title=A Chauvet Primer |journal=Archaeology |volume=64 |issue=2 |date=March\u2013April 2011 |page=39 |url=http://archive.archaeology.org/1103/features/werner_herzog_chauvet_cave_primer.html}}</ref> \n[[File:Rhinos Chauvet Cave.jpg|thumb|left|An artistic depiction of a group of rhinoceros, was completed in the [[Chauvet Cave]] 30,000 to 32,000 years ago.]]\nIn 2009, [[Caving|cavers]] discovered drawings in [[Coliboaia Cave]] in Romania, stylistically comparable to those at Chauvet.<ref name=Coliboaia_Ghemis>{{cite journal |last=Ghemis |first=Calin|author2=Clottes, J. |author3=Gely, B. |author4= Prudhomme, F. |title=An Exceptional Archaeological Discovery \u2013 the "Art Gallery" in Coliboaia Cave |journal=Acta Archaeologica Carpathica |year=2011 |volume=XLVI |url=https://www.academia.edu/1488865 |access-date=7 March 2013 |issn=0001-5229}}</ref> An initial dating puts the age of an image in the same range as Chauvet: about 32,000 years old.<ref name=Coliboaia_Zorich>{{cite journal|last=Zorich|first=Zach|title=From the Trenches \u2013 Drawing Paleolithic Romania|journal=Archaeology|date=January\u2013February 2012|volume=65|issue=1|url=http://archive.archaeology.org/1201/trenches/coliboaia_cave_romania_charcoal_drawings.html|access-date=7 March 2013}}</ref>\n\nIn Australia, cave paintings have been found on the [[Arnhem Land]] plateau showing [[megafauna]] which are thought to have been extinct for over 40,000 years, making this site another candidate for oldest known painting; however, the proposed age is dependent on the estimate of the extinction of the species seemingly depicted.<ref name=abc_megafauna>{{cite web|last=Masters|first=Emma|title=Megafauna cave painting could be 40,000 years old|url=http://www.abc.net.au/news/2010-05-31/megafauna-cave-painting-could-be-40000-years-old/847564|publisher=Australian Broadcasting Commission (ABC)|access-date=30 December 2012|date=May 31, 2010}}</ref>  Another Australian site, [[Gabarnmung|Nawarla Gabarnmang]], has charcoal drawings that have been radiocarbon-dated to 28,000 years, making it the oldest site in Australia and among the oldest in the world for which reliable date evidence has been obtained.<ref name=CSM_rockart>{{cite news|last=McGuirk|first=Rod|title=Australian rock art among the world's oldest|url=http://www.csmonitor.com/Science/2012/0618/Australian-rock-art-among-world-s-oldest|access-date=30 December 2012|newspaper=Christian Science Monitor|date=June 18, 2012|agency=AP}}</ref>\n\nOther examples may date as late as the Early Bronze Age, but the well-known [[Magdalenian]] style seen at [[Lascaux]] in France (c.{{space}}15,000 BC) and [[Cave of Altamira|Altamira]] in Spain died out about 10,000{{space}}BC, coinciding with the advent of the [[Neolithic period]].  Some caves probably continued to be painted over a period of several thousands of years.<ref name=telegraph_20000>{{cite news|last=Gray|first=Richard|title=Prehistoric cave paintings took up to 20,000 years to complete|url=https://www.telegraph.co.uk/earth/3352850/Prehistoric-cave-paintings-took-up-to-20000-years-to-complete.html|archive-url=https://web.archive.org/web/20090615073824/http://www.telegraph.co.uk/earth/3352850/Prehistoric-cave-paintings-took-up-to-20000-years-to-complete.html|url-status=dead|archive-date=15 June 2009|access-date=30 December 2012|newspaper=The Telegraph|date=5 October 2008}}</ref>\n\nThe next phase of surviving European prehistoric painting, the [[rock art of the Iberian Mediterranean Basin]], was very different, concentrating on large assemblies of smaller and much less detailed figures, with at least as many humans as animals.  This was created roughly between 10,000 and 5,500 years ago, and painted in rock shelters under cliffs or shallow caves, in contrast to the recesses of deep caves used in the earlier (and much colder) period.  Although individual figures are less naturalistic, they are grouped in coherent grouped compositions to a much greater degree.\n\n [[File:Rock art bull.jpg|thumb|Prehistoric cave painting of animals at Albarrac\u00edn, Teruel, Spain ([[rock art of the Iberian Mediterranean Basin]])]]\n\nCave artists use a variety of techniques such as finger tracing, modeling in clay, engravings, bas-relief sculpture, hand stencils, and paintings done in two or three colors. Scholars classify cave art as "Signs" or abstract marks. \n<ref>{{cite book |last1=Renfrew |first1=Colin |title=Archaeology Theories, Methods and Practice |publisher=Thames and Hudson |edition=7th}}</ref>  The most common subjects in cave paintings are large wild animals, such as [[bison]], [[horse]]s, [[aurochs]], and [[deer]], and tracings of human hands as well as abstract patterns, called [[finger flutings]]. The species found most often were suitable for hunting by humans, but were not necessarily the actual typical prey found in associated deposits of bones; for example, the painters of Lascaux have mainly left reindeer bones, but this species does not appear at all in the cave paintings, where [[equine]] species are the most common.  Drawings of humans were rare and are usually schematic as opposed to the more detailed and naturalistic images of animal subjects. Kieran D. O'Hara, geologist, suggests in his book ''Cave Art and Climate Change'' that climate controlled the themes depicted.<ref>O'Hara, K. (2014). Cave Art and Climate Change, Archway Publishing.</ref>\nPigments used include red and yellow [[ochre]], [[hematite]], [[manganese oxide]] and [[charcoal]]. Sometimes the silhouette of the animal was incised in the rock first, and in some caves all or many of the images are only engraved in this fashion,{{citation needed|date=April 2021}} taking them somewhat out of a strict definition of "cave painting".\n\nSimilarly, large animals are also the most common subjects in the many small carved and engraved bone or ivory (less often stone) pieces dating from the same periods.  But these include the group of [[Venus figurine]]s, which have no real equivalent in cave paintings.{{citation needed|date=December 2012}}\n\nHand stencils, formed by placing a hand against the wall and covering the surrounding area in pigment result in the characteristic image of a roughly round area of solid pigment with the uncoloured shape of the hand in the centre, these may then be decorated with dots, dashes, and patterns. Often, these are found in the same caves as other paintings, or may be the only form of painting in a location. Some walls contain many hand stencils.  Similar hands are also painted in the usual fashion. A number of hands show a finger wholly or partly missing, for which a number of explanations have been given. Hand images are found in similar forms in Europe, Eastern Asia and South America.<ref>{{cite web|url=http://www.bradshawfoundation.com/hands/|title=Hand Paintings and Symbols in Rock Art|first=Bradshaw|last=Foundation|work=bradshawfoundation.com}}</ref>\n\n [[File:Bestias11.JPG|thumb|Rock paintings from the [[Cave of Beasts]] ([[Gilf Kebir]], [[Libyan Desert]]) Estimated 7000 [[Before Present|BP]] ]]\nIn the early 20th century, following the work of [[Walter Baldwin Spencer]] and [[Francis James Gillen]], scholars such as [[Salomon Reinach]], [[Henri Breuil]] and {{Ill|Henri Begou\u00ebn|lt=Count B\u00e9gou\u00ebn|fr}} interpreted the paintings as 'utilitarian' [[hunting magic]] to increase the abundance of prey.<ref>{{Cite web|date=9 December 2019|title=Hunting magic in rock art|url=https://bradshawfoundation.com/news/rock_art.php?id=Hunting-magic-in-rock-art|access-date=2021-05-25|website=Bradshaw Foundation}}</ref> [[Jacob Bronowski]] states, "I think that the power that we see expressed here for the first time is the power of anticipation: the forward-looking imagination. In these paintings the hunter was made familiar with dangers which he knew he had to face but to which he had not yet come."<ref>{{Cite book|last=Bronowski|first=Jacob|url=http://archive.org/details/ascentofman0000bron_y1z2|title=The Ascent of Man|publisher=BBC Books|year=1990|isbn=978-0-563-20900-3|location=London|pages=54|orig-year=1973}}</ref>\n\nAnother theory, developed by [[David Lewis-Williams]] and broadly based on ethnographic studies of contemporary [[hunter-gatherer]] societies, is that the paintings were made by paleolithic [[Shamanism|shamans]].<ref>{{cite book|last=Whitley|first=David S.|title=Cave Paintings and the Human Spirit: The Origin of Creativity and Belief|year=2009|publisher= Prometheus|isbn= 978-1-59102-636-5|page=35}}</ref> The shaman would retreat into the darkness of the caves, enter into a trance state, then paint images of their visions, perhaps with some notion of drawing out power from the cave walls themselves.\n\nR. Dale Guthrie, who has studied both highly artistic and lower quality art and figurines, identifies a wide range of skill and age among the artists. He hypothesizes that the main themes in the paintings and other artifacts (powerful beasts, risky hunting scenes and the representation of women in the [[Venus figurines]]) are the work of adolescent males, who constituted a large part of the [[prehistoric demography|human population at the time]].<ref name=guthrie>{{cite book|last=Guthrie|first=R. Dale|title=The Nature of Paleolithic Art|year=2005|publisher=Univ. of Chicago Press|location=Chicago [u.a.]|isbn=978-0-226-31126-5|chapter=Preface: Reassembling the Bones |chapter-url=http://www.press.uchicago.edu/Misc/Chicago/311260.html |access-date=31 December 2012}}</ref>{{check|date=December 2012}} However, in analyzing hand prints and stencils in French and Spanish caves, Dean Snow of Pennsylvania State University has proposed that a proportion of them, including those around the spotted horses in Pech Merle, were of female hands.<ref name=times_handprints>{{cite news|last=Hammond|first=Norman|title=Cave painters' giveaway handprints at Pech-Merle|url=http://www.thetimes.co.uk/tto/life/courtsocial/article1818692.ece|access-date=31 December 2012|newspaper=The Times|date=September 11, 2009}}</ref>\n\n {{see|Paleolithic art}}\n\n {{See also|Caves in Cantabria}}\n[[File:20,000 Year Old Cave Paintings Hyena.png|thumb|right|30,000-year-old [[cave hyena]] painting found in the [[Chauvet Cave]], France]]\n[[File:Cave of Altamira and Paleolithic Cave Art of Northern Spain-110113.jpg|thumb|[[Cave of Altamira and Paleolithic Cave Art of Northern Spain]]]]\nWell-known cave paintings include those of:\n* [[Cave of El Castillo]], Spain (~40.000 y.o.)\n*[[Kapova Cave]], [[Bashkortostan]], Russia (~36,000 y.o.)<ref>{{Cite web|url=http://u7a.ru/articles/society/11854|title=\u0411\u0430\u0448\u043a\u0438\u0440\u0438\u044f: \u043d\u043e\u0432\u044b\u0435 \u0438\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u043d\u0438\u044f "\u0441\u043e\u0441\u0442\u0430\u0440\u0438\u043b\u0438" \u043d\u0430\u0441\u043a\u0430\u043b\u044c\u043d\u044b\u0435 \u0440\u0438\u0441\u0443\u043d\u043a\u0438 \u041a\u0430\u043f\u043e\u0432\u043e\u0439 \u043f\u0435\u0449\u0435\u0440\u044b \u0432 \u0434\u0432\u0430 \u0440\u0430\u0437\u0430|website=u7a.ru|access-date=2019-10-11}}</ref>\n* [[Chauvet Cave]], near [[Vallon-Pont-d'Arc]], France (~35,000 y.o.)\n* [[Cave of La Pasiega]], [[Cuevas de El Castillo]], [[Cantabria]], Spain (~30,000 y.o.?)\n* [[Caves of Arcy-sur-Cure]], France (~28,200 y.o.)\n* [[Cosquer Cave]], with an entrance below [[sea level]] near [[Marseille, France]] (~27,000 y.o.)\n* [[Caves of Gargas]], France (~27,000 y.o.)\n* [[Grotte de Cussac]], France (~25,000 y.o.)\n* [[Pech Merle]], near [[Cabrerets]], France (25,000 y.o.)\n* [[Lascaux]], France (~17,000 y.o.)\n* [[Cave of Niaux]], France (~17,000 y.o.)\n* [[Font-de-Gaume]], in the [[Dordogne]] Valley, France (~17,000 y.o.)\n* [[Cave of Altamira]], near [[Santillana del Mar]], [[Cantabria]], Spain (~15,500 y.o.)\n* [[La Marche (cave)|La Marche]], in [[Lussac-les-Ch\u00e2teaux]],  France (~15,000 y.o.)\n* [[Les Combarelles]], in [[Les Eyzies-de-Tayac-Sireuil|Les Eyzies de Tayac]], [[Dordogne]], France (~13,600 y.o.)\n* [[Cave of the Trois-Fr\u00e8res]], in [[Ari\u00e8ge (department)|Ari\u00e8ge]], France (~13,000 y.o.)<ref>{{cite web |title=Trois Fr\u00e8res |url=https://www.britannica.com/place/Trois-Freres#ref=ref893311 |website=[[Encyclop\u00e6dia Britannica Online|Encyclop\u00e6dia Britannica]] |language=en |access-date=February 23, 2020}}</ref>\n* [[Magura Cave]], Bulgaria (~10,000 y.o.)\n\n[[File:Men of the old stone age (1915) Wolf.png|thumb|[[Polychrome]] cave painting of a [[wolf]], Font-de-Gaume, France]]\n\nOther sites include [[Creswell Crags]], [[Nottinghamshire]], England (~14,500 ys old cave etchings and [[bas-reliefs]] discovered in 2003), [[Pe\u0219tera Coliboaia]] in [[Romania]] (~29,000 y.o. art?).<ref>{{cite news |last=Tugman |first=Lindsey |url=http://www.thv11.com/news/article/171246/288/Oldest-cave-drawings-found-in-Romanian-cave |title=Oldest cave drawings found in Romanian cave |agency=CBS News |date=1 September 2011 |access-date=11 May 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130921063051/http://www.thv11.com/news/article/171246/288/Oldest-cave-drawings-found-in-Romanian-cave |archive-date=21 September 2013 }}</ref>\n\nRock painting was also performed on cliff faces; but fewer of those have survived because of [[erosion]]. One example is the rock paintings of [[Astuvansalmi]] (3000\u20132500 BC) in the [[Saimaa]] area of Finland.\n\nWhen [[Marcelino Sanz de Sautuola]] first encountered the [[Magdalenian]] paintings of the Cave of Altamira in Cantabria, Spain in 1879, the academics of the time considered them hoaxes. Recent reappraisals and numerous additional discoveries have since demonstrated their authenticity, while at the same time stimulating interest in the artistry and symbolism<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211205/hJnEQCMA5Sg Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20151218194343/https://www.youtube.com/watch?v=hJnEQCMA5Sg&gl=US&hl=en Wayback Machine]{{cbignore}}: {{cite web| url = https://www.youtube.com/watch?v=hJnEQCMA5Sg| title = Why are these 32 symbols found in caves all over Europe {{!}} Genevieve von Petzinger | website=[[YouTube]]}}{{cbignore}}</ref> of [[Upper Palaeolithic]] peoples.\n{{clear left}}\n\n [[File:Hands in Pettakere Cave DYK crop.jpg|alt=Cave of Pettakere, Bantimurung district (kecamatan), South Sulawesi, Indonesia. Hand stencils estimated between 0,000 years old<ref>{{cite journal | last1 = Aubert | first1 = M. | display-authors = etal | year = 2014| title = Pleistocene cave art from Sulawesi, Indonesia | journal = Nature | volume = 514 | issue = 7521| pages = 223\u2013227 | quote = using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. | doi = 10.1038/nature13422 | pmid = 25297435| bibcode = 2014Natur.514..223A | s2cid = 2725838 }}</ref>|thumb|[[Caves in the Maros-Pangkep karst]] ([[Sulawesi]], Indonesia). Hand stencils estimated between 35,000\u201340,000 [[Before Present|BP]], stencils of right hands shown.]]\n\nIn [[Indonesia]] the [[caves in the district of Maros]] in [[Sulawesi]] are famous for their hand prints. About 1,500 negative handprints have also been found in 30 painted caves in the Sangkulirang area of Kalimantan; preliminary dating analysis as of 2005 put their age in the range of 10,000 years old.<ref>{{cite journal|last=Chazine|first=J-M.|title=Rock Art, Burials, and Habitations: Caves in East Kalimantan |journal=Asian Perspectives |year=2005 |volume=44 |issue=1 |pages=219\u2013230 |doi=10.1353/asi.2005.0006 |hdl=10125/17232|s2cid=53372873|url=http://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/17232/AP-v44n1-219-230.pdf?sequence=1 |access-date=12 May 2013|hdl-access=free }}\n{{cite journal |last=Fage |first=Luc-Henri |title=Hands Across Time: Exploring the Rock Art of Borneo |journal=National Geographic |date=August 2005 |volume=208 |issue=2 |pages=44\u201345 |url=http://ngm.nationalgeographic.com/print/features/world/asia/indonesia/cave-art-text |access-date=7 October 2013}}</ref> A 2014 study based on [[uranium\u2013thorium dating]] dated a Maros hand stencil to a minimum age of 39,900 years. A painting of a [[babirusa]] was dated to at least 35.4 ka, placing it among the oldest known figurative depictions worldwide.<ref name=Aubert2014/>\n\nIn November 2018, scientists reported the discovery of the oldest known [[Figurative art|figurative art painting]], over 40,000 (perhaps as old as 52,000) years old, of an unknown animal, in the cave of [[Lubang Jeriji Sal\u00e9h]] on the [[Indonesia]]n island of [[Borneo]].<ref name="NYT-20181107-cz">{{cite news |last=Zimmer |first=Carl |author-link=Carl Zimmer |title=In Cave in Borneo Jungle, Scientists Find Oldest Figurative Painting in the World - A cave drawing in Borneo is at least 40,000 years old, raising intriguing questions about creativity in ancient societies. |url=https://www.nytimes.com/2018/11/07/science/oldest-cave-art-borneo.html |date=7 November 2018 |work=[[The New York Times]] |access-date=8 November 2018 }}</ref><ref name="NAT-20181107">{{cite journal |author=Aubert, M.|display-authors=et al |title=Palaeolithic cave art in Borneo |date=7 November 2018 |journal=[[Nature (journal)|Nature]] |doi=10.1038/s41586-018-0679-9 |pmid=30405242 |volume=564 |issue=7735 |pages=254\u2013257 |bibcode=2018Natur.564..254A |s2cid=53208538 }}</ref>\n\nAnd more recently, in 2021, archaeologists announced the discovery of cave art at least 45,500 years old in Leang Tedongnge cave, Indonesia. According to the journal ''[[Science Advances]]'', the cave painting of a warty pig is the earliest evidence of human settlement of the region.<ref>{{Cite web|last=France-Presse|first=Agence|date=2021-01-13|title=World's 'oldest known cave painting' found in Indonesia|url=http://www.theguardian.com/science/2021/jan/13/worlds-oldest-known-cave-painting-found-in-indonesia|access-date=2021-02-24|website=The Guardian|language=en}}</ref><ref>{{Cite news|date=2021-01-14 |title=Indonesia: Archaeologists find world's oldest animal cave painting |language=en-GB |work=BBC News |url=https://www.bbc.com/news/world-asia-55657257|access-date=2021-02-24}}</ref> It has been reported that it is rapidly deteriorating as a result of climate change in the region.<ref>{{Cite news|date=2021-05-19 |title=Indonesia: Climate change destroying world's oldest animal painting |language=en-GB |work=BBC News|url=https://www.bbc.com/news/world-asia-57166995|access-date=2021-05-19}}</ref>\n\nOriginating in the Paleolithic period, [[Khoit Tsenkher Cave Rock Art|the rock art found in Khoit Tsenkher Cave]], Mongolia, includes symbols and animal forms painted from the walls up to the ceiling.<ref>[https://whc.unesco.org/en/tentativelists/935/ Khoit tsenkher cave rock painting \u2013 UNESCO World Heritage Centre]</ref> Stags, buffalo, oxen, ibex, lions, Argali sheep, antelopes, camels, elephants, ostriches, and other animal pictorials are present, often forming a palimpsest of overlapping images. The paintings appear brown or red in color, and are stylistically similar to other Paleolithic rock art from around the world but are unlike any other examples in Mongolia.\n\nThe [[Padah-Lin Caves]] of [[Burma]] contain 11,000-year-old paintings and many rock tools.\n\n {{Main|Cave paintings in India}}\n[[File:Bhimbetka rock paintng1.jpg|thumb|right|[[Bhimbetka rock shelters|Bhimbetka]] rock painting]]\nThe [[Bhimbetka rock shelters]] exhibit the earliest traces of human life in India. Paintings in Bhimbetka are dated to about 8,000 BC.<ref>{{cite book |last1=Mathpal |first1=Yashodhar |title=Prehistoric Painting Of Bhimbetka |date=1984 |publisher=Abhinav Publications |isbn=9788170171935 |page=220 |url=https://books.google.com/books?id=GG7-CpvlU30C&pg=PA220 |language=en}}</ref><ref>{{cite book |last1=Tiwari |first1=Shiv Kumar |title=Riddles of Indian Rockshelter Paintings |date=2000 |publisher=Sarup & Sons |isbn=9788176250863 |page=189 |url=https://books.google.com/books?id=-jO0fvT4r9gC&pg=PA189 |language=en}}</ref><ref>{{cite book |title=Rock Shelters of Bhimbetka |date=2003 |publisher=UNESCO |page=16 |url=https://whc.unesco.org/uploads/nominations/925.pdf}}</ref><ref>{{cite book |last1=Mithen |first1=Steven |title=After the Ice: A Global Human History, 20,000 - 5000 BC |date=2011 |publisher=Orion |isbn=9781780222592 |page=524 |url=https://books.google.com/books?id=Uaxg_QDSsrQC&pg=PT524 |language=en}}</ref><ref>{{cite book |last1=Javid |first1=Ali |last2=J\u0101v\u012bd |first2=\u02bbAl\u012b |last3=Javeed |first3=Tabassum |title=World Heritage Monuments and Related Edifices in India |date=2008 |publisher=Algora Publishing |isbn=9780875864846 |page=19 |url=https://books.google.com/books?id=54XBlIF9LFgC&pg=PA19 |language=en}}</ref> Similar paintings are found in other parts of India as well. In Tamil Nadu, ancient Paleolithic Cave paintings are found in Kombaikadu, Kilvalai, Settavarai and Nehanurpatti. In Odisha they are found in Yogimatha and Gudahandi. In Karnataka, these paintings are found in Hiregudda near Badami. The most recent painting, consisting of geometric figures, date to the [[Middle Ages|medieval period]].\nExecuted mainly in red and white with the occasional use of green and yellow, the paintings depict the lives and times of the people who lived in the caves, including scenes of childbirth, communal dancing and drinking, religious rites and burials, as well as indigenous animals.<ref>{{cite web|url=https://whc.unesco.org/pg.cfm?cid=31&id_site=925|title=Rock Shelters of Bhimbetka|publisher=World Heritage Site|access-date=2009-12-22}}</ref>\n\n Cave paintings found at the [[Apollo 11 Cave]] in [[Namibia]] are estimated to date from approximately 25,500\u201327,500 years ago.<ref>{{cite web |url=http://www.metmuseum.org/toah/hd/apol/hd_apol.htm |title=Apollo 11 (ca. 25,500\u201323,500 B.C.) and Wonderwerk (ca. 8000 B.C.) Cave Stones |work=Heilbrunn Timeline of Art History |publisher=The Metropolitan Museum of Art |location=New York |date=October 2000 |access-date=11 May 2013}}</ref>\n\nIn 2011, archaeologists found a small rock fragment at [[Blombos Cave]], about {{convert|300|km|mi|abbr=on}} east of [[Cape Town]] on the southern cape coastline in [[South Africa]], among spear points and other excavated material. After extensive testing for seven years, it was revealed that the lines drawn on the rock were handmade and from an ochre crayon dating back 73,000 years. This makes it the oldest known rock painting.<ref name="NYT-20180912">{{cite news |last=St. Fleur |first=Nicholas|title=Oldest Known Drawing by Human Hands Discovered in South African Cave |url=https://www.nytimes.com/2018/09/12/science/oldest-drawing-ever-found.html |date=12 September 2018 |work=[[The New York Times]] |access-date=15 September 2018 }}</ref><ref>{{Cite web|url=https://www.theguardian.com/science/2018/sep/12/earliest-known-drawing-found-on-rock-in-south-african-cave|title=Earliest known drawing found on rock in South African cave|last=Sample|first=Ian|date=2018-09-12|website=The Guardian|language=en|access-date=2018-09-12}}</ref>\n\n [[Image:(1)Jabiru_dreaming-7.jpg|right|thumb|Painting at Jabiru Dreaming, Kakadu National Park]]\nSignificant early cave paintings, executed in [[ochre]], have been found in [[Kimberley (Western Australia)|Kimberley]] and [[Kakadu National Park|Kakadu]], Australia. Ochre is not an [[organic material]], so [[carbon dating]] of these pictures is often impossible. The oldest so far dated at 17,300 years is an ochre painting of a [[kangaroo]] in the [[Kimberley (Western Australia)|Kimberley]] region, which was dated by carbon dating wasp nest material underlying and overlying the painting.<ref>{{cite web |title=Australia: Oldest rock art is 17,300-year-old kangaroo |url=https://www.bbc.co.uk/news/world-australia-56164484 |website=BBC News |publisher=BBC|date=23 February 2021|access-date=25 February 2021}}</ref>  Sometimes the approximate date, or at least, an [[Epoch (reference date)|epoch]], can be surmised from the painting content, contextual artifacts, or organic material intentionally or inadvertently mixed with the inorganic ochre paint, including torch soot.<ref name=valladas />\n\nA red ochre painting, discovered at the centre of the [[Arnhem Land Plateau]], depicts two [[emu]]-like birds with their necks outstretched. They have been identified by a palaeontologist as depicting the [[megafauna]] species ''[[Genyornis]]'', giant birds thought to have become extinct more than 40,000 years ago; however, this evidence is inconclusive for dating.  It may suggest that Genyornis became extinct at a later date than previously determined.<ref name=abc_megafauna />\n\n[[Hook Island]] in the [[Whitsunday Islands National Park|Whitsunday Islands]] is also home to a number of cave paintings created by the seafaring [[Ngaro people]].<ref>{{cite web|title=Whitsunday national park islands - Nature, Culture and History|url=https://www.npsr.qld.gov.au/parks/parks-whitsundays/culture.html|website=Queensland Government|publisher=The State of Queensland (Department of National Parks, Sport and Racing)|access-date=16 October 2017}}</ref>\n\n [[File:Dera rock art.jpg|thumb|Dera Rock Art in, [[Eritrea]]]]\n\n In the [[Philippines]] at [[Tabon Caves]] the oldest artwork may be a relief of a shark above the cave entrance. It was partially disfigured by a later jar burial scene.{{citation needed|date=August 2018}}\n\nThe [[Edakkal Caves]] of Kerala, India, contain drawings that range over periods from the Neolithic as early as 5,000 BC to 1,000 BC.<ref>{{cite news|url=http://newindianexpress.com/cities/thiruvananthapuram/article142152.ece |title='Edakkal cave findings related to Indus Valley civilization |newspaper=The New Indian Express |date=2009-10-22 |access-date=2012-08-17}}</ref><ref>{{cite web|url=https://www.scribd.com/doc/26510292/Sarasvati-River-Indus-Script-Ancient-Village-Or |title=Sarasvati River Indus Script Ancient Village Or |publisher=Scribd.com |access-date=2012-08-17}}</ref><ref>{{cite news|url=http://www.hindustantimes.com/Symbols-akin-to-Indus-valley-culture-discovered/Article1-459163.aspx |title=Symbols akin to Indus valley culture discovered |newspaper=Hindustan Times |date=2009-09-29 |access-date=2012-08-17 |url-status=dead |archive-url=https://web.archive.org/web/20110128222211/http://www.hindustantimes.com/Symbols-akin-to-Indus-valley-culture-discovered/Article1-459163.aspx |archive-date=2011-01-28 }}</ref>\n\n [[File:Kohaito, grotta di adi alauti con pitture rupestri databili al 2500 ac ca. 36 dromedari.JPG|thumb|Rock art in the Adi Alauti cave, [[Eritrea]]]]\n[[File:Laas Geel.jpg|thumb|Cave paintings at the [[Laas Geel]] complex in northern [[Somaliland]].]]\n[[Rock art]] near Qohaito appears to indicate habitation in the area since the [[fifth millennium BC]], while the town is known to have survived to the sixth century AD. Mount [[Emba Soira]], Eritrea's highest mountain, lies near the site, as does a small successor village. Much of the rock art sites are found together with evidence of prehistoric stone tools, suggesting that the art could predate the widely presumed pastoralist and domestication events that occurred 5000\u2013 4000 years ago.<ref>{{Cite web|last=Admin|title=Understanding Rock Art in Eritrea|url=http://www.madote.com/2017/04/understanding-rock-art-in-eritrea.html|access-date=2021-02-16|website=Madote}}</ref><ref>{{Cite web|last=Centre|first=UNESCO World Heritage|title=Qoahito Cultural Landscape|url=https://whc.unesco.org/en/tentativelists/5600/|access-date=2021-02-16|website=UNESCO World Heritage Centre|language=en}}</ref>\n\nIn 2002, a French archaeological team discovered the [[Laas Geel]] cave paintings on the outskirts of [[Hargeisa]] in [[Somaliland]]. Dating back around 5,000 years, the paintings depict both wild animals and decorated cows. They also feature herders, who are believed to be the creators of the rock art.<ref name="Bakano">{{cite news|last=Bakano|first=Otto|url=https://www.google.com/hostednews/afp/article/ALeqM5jMNd90UAafsRNEDPyelL7Hee1ydw?docId=CNG.82196a5b15ef45a2d4e744675740cd6a.6e1 |title=Grotto galleries show early Somali life |agency=AFP |date=April 24, 2011|access-date=11 May 2013}}</ref> In 2008, Somali archaeologists announced the discovery of other cave paintings in [[Dhambalin]] region, which the researchers suggest includes one of the earliest known depictions of a hunter on horseback. The rock art is dated to 1000 to 3000 BC.<ref name="Tdodras">{{cite journal|last=Mire|first=Sada|title=The Discovery of Dhambalin Rock Art Site, Somaliland|journal=African Archaeological Review|year=2008|volume=25|issue=3\u20134|pages=153\u2013168|url=http://www.mbali.info/doc494.htm|access-date=22 June 2013|doi=10.1007/s10437-008-9032-2|s2cid=162960112|url-status=dead|archive-url=https://web.archive.org/web/20130627100400/http://www.mbali.info/doc494.htm|archive-date=27 June 2013}}</ref><ref name="Guafcpaonas">{{cite news|last=Alberge|first=Dalya|title=UK archaeologist finds cave paintings at 100 new African sites|url=https://www.theguardian.com/world/2010/sep/17/cave-paintings-found-in-somaliland|access-date=25 June 2013|newspaper=The Guardian|date=17 September 2010}}</ref>\n\nAdditionally, between the towns of [[Las Khorey]] and [[El Ayo]] in [[Karinhegane]] is a site of numerous cave paintings of real and mythical animals. Each painting has an inscription below it, which collectively have been estimated to be around 2,500 years old.<ref name="Mheah">{{cite book|last=Hodd|first=Michael|title=East African Handbook|year=1994|publisher=Trade & Travel Publications|isbn=0-8442-8983-3|page=640|url=https://books.google.com/books?id=bL8tAQAAIAAJ}}</ref><ref name="Astgi">{{cite book|last=Ali|first=Ismail Mohamed|title=Somalia Today: General Information|year=1970|publisher=Ministry of Information and National Guidance, Somali Democratic Republic|page=295|url=https://books.google.com/books?id=tMVAAAAAYAAJ}}</ref> Karihegane's rock art is in the same distinctive style as the Laas Geel and Dhambalin cave paintings.<ref name="Iodn">{{cite book|last=Istituto universitario orientale (Naples, Italy)|title=Annali: Supplemento, Issues 70-73|year=1992|publisher=Istituto orientale di Napoli|page=57|url=https://www.google.com/books?id=DbhiAAAAMAAJ}}</ref><ref name="Crasos">{{cite web|title=Rock Art Sites of Somaliland|url=http://archive.cyark.org/rock-art-sites-of-somaliland-info|publisher=CyArk|access-date=28 March 2014|archive-url=https://web.archive.org/web/20140329002706/http://archive.cyark.org/rock-art-sites-of-somaliland-info|archive-date=29 March 2014|url-status=dead}}</ref> Around 25 miles from Las Khorey is found [[Gelweita]], another key rock art site.<ref name="Astgi" />\n\nIn [[Djibouti]], rock art of what appear to be antelopes and a giraffe are also found at [[Dorra]] and [[Balho]].<ref name="Amvjaa">{{citation |author=Universit\u00e4t Frankfurt am Main|journal=[[Journal of African Archaeology]] |title=Volumes 1\u20132 |date=2003|publisher=Africa Manga Verlag|page=230|url=https://www.google.com/books?id=ExwkAQAAIAAJ|access-date=7 September 2014}}</ref>\n\n [[File:Tassili - catapulte?.jpg|thumb|right|Cave painting at the [[Tassili n'Ajjer]] UNESCO World Heritage Site in southeast [[Algeria]].]]\nMany cave paintings are found in the [[Tassili n'Ajjer]] mountains in southeast [[Algeria]]. A [[UNESCO World Heritage Site]], the rock art was first discovered in 1933 and has since yielded 15,000 engravings and drawings that keep a record of the various animal migrations, climatic shifts, and change in human inhabitation patterns in this part of the Sahara from 6000 BC to the [[Classical antiquity#Roman Empire|late classical period]].<ref name=tassili>{{cite web|title=Tassili n'Ajjer|url=https://whc.unesco.org/en/list/179|publisher=UNESCO World Heritage Center|access-date=31 December 2012}}</ref> Other cave paintings are also found at the [[Akakus]], [[Mesak Settafet]] and [[Tadrart Acacus|Tadrart]] in [[Libya]] and other Sahara regions including: Ayr mountains, Niger and Tibesti, Chad.\n\nThe [[Cave of Swimmers]] and the [[Cave of Beasts]] in southwest [[Egypt]], near the border with Libya, in the mountainous [[Gilf Kebir]] region of the [[Sahara Desert]]. The Cave of Swimmers was discovered in October 1933 by the [[Hungary|Hungarian]] explorer [[L\u00e1szl\u00f3 Alm\u00e1sy]]. The site contains [[rock painting]] images of people swimming, which are estimated to have been created 10,000 years ago during the time of the most recent Ice Age.\n\nIn 2020, [[Solutional cave|limestone cave]] decorated with scenes of animals such as [[donkey]]s, [[camel]]s, [[deer]], [[mule]] and [[mountain goat]]s was uncovered in the area of Wadi Al-Zulma by the archaeological mission from the Tourism and Antiquities Ministry. Rock art cave is 15 meters deep and 20 meters high.<ref>{{Cite web|title=Ancient cave with distinguished engravings depicting scenes of animals discovered in Sinai - Ancient Egypt - Heritage|url=http://english.ahram.org.eg/NewsContent/9/40/368014/Heritage/Ancient-Egypt/Ancient-cave-with-distinguished-engravings-depicti.aspx|access-date=2020-09-09|website=Ahram Online|language=en}}</ref><ref>{{Cite web|date=2020-04-26|title=Photos: Archaeologists uncover ancient cave in North Sinai|url=https://egyptindependent.com/photos-archaeologists-uncover-ancient-cave-in-north-sinai/|access-date=2020-09-09|website=Egypt Independent|language=en-US}}</ref>\n\n [[File:Southafrica468bushman.jpg|thumb|right|[[San rock art|San rock paintings]] from the [[Western Cape]] in [[South Africa]].]]\nAt [[uKhahlamba / Drakensberg Park]], [[South Africa]], now thought to be some 3,000 years old, the paintings by the [[San people]] who settled in the area some 8,000 years ago depict animals and humans, and are thought to represent religious beliefs. Human figures are much more common in the rock art of Africa than in Europe.<ref>{{cite news |first=Leon |last=Jaroff |title=Etched in Stone |url=http://www.time.com/time/printout/0,8816,986446,00.html |archive-url=https://archive.today/20130204205110/http://www.time.com/time/printout/0,8816,986446,00.html |url-status=dead |archive-date=February 4, 2013 |work=Time |date=1997-06-02 |access-date=2008-10-07 |quote=Wildlife and humans tend to get equal billing in African rock art. (In the caves of western Europe, by contrast, pictures of animals cover the walls and human figures are rare.) In southern Africa, home to the San, or Bushmen, many of the rock scenes depicting people interpret the rituals and hallucinations of the shamans who still dominate the San culture today. Among the most evocative images are those believed to represent shamans deep in trance: a reclining, antelope-headed man surrounded by imaginary beasts, for example, or an insect-like humanoid covered with wild decorations.}}</ref>\n\n [[File:2009 07 09 camino cielo paradise 137.jpg|thumb|right|Painted Cave, [[Santa Barbara County, California]]]]\n\n{{Main|Great Mural Rock Art}}\nDistinctive monochrome and polychrome cave paintings and murals exist in the mid-peninsula regions of southern [[Baja California]] and northern [[Baja California Sur]], consisting of [[Pre-Columbian era|Pre-Columbian]] paintings of humans, land animals, sea creatures, and abstract designs. These paintings are mostly confined to the sierras of this region, but can also be found in outlying mesas and rock shelters. According to recent [[Radiocarbon dating|radiocarbon]] studies of the area, of materials recovered from archaeological deposits in the rock shelters and on materials in the paintings themselves, suggest that the Great Murals may have a time range extending as far back as 7,500 years ago.<ref>{{Cite web|url=http://news.nationalgeographic.com/news/2003/07/0717_030717_bajarockart.html|title=Baja California Rock Art Dated to 7,500 Years Ago|website=news.nationalgeographic.com|access-date=2016-03-29}}</ref>{{Further|Rock art of the Chumash people}}\n\nNative artists in the [[Chumash people|Chumash]] tribes created [[Rock art of the Chumash people|cave paintings]] that are located in present-day [[Santa Barbara, California|Santa Barbara]], [[Ventura County, California|Ventura]], and [[San Luis Obispo County, California|San Luis Obispo Counties]] in Southern [[California]] in the [[United States]]. They include examples at [[Burro Flats Painted Cave]] and [[Chumash Painted Cave State Historic Park, California|Chumash Painted Cave State Historic Park]].\n\nThere are also [[Native Americans in the United States|Native American]] [[pictogram]] examples in caves of the [[Southwestern United States]].  Cave art that is 6,000 years old was found in the [[Cumberland Plateau]] region of [[Tennessee]].<ref>{{Cite journal|title=Sacred landscapes of the south-eastern USA: prehistoric rock and cave art in Tennessee |author1 = Simekm Jan F. |author2 =Alan Cressler |author3 =Nicholas P. Herrmann |author4 =Sarah C. Sherwood|year=2013|journal=Antiquity |volume=87|issue=336 |pages=430\u2013446|doi=10.1017/S0003598X00049048 }}</ref>\n\n [[File:Serra da Capivara - Several Paintings 2b.jpg|thumb|Cave painting at Serra da Capivara National Park, [[Brazil]]]]\n[[Serra da Capivara National Park]] is a [[national park]] in the north east of Brazil with many prehistoric paintings; the park was created to protect the prehistoric artifacts and paintings found there. It became a [[World Heritage Site]] in 1991. Its best known archaeological site is [[Pedra Furada Site|Pedra Furada]].\n\nIt is located in northeast state of [[Piau\u00ed]], between latitudes 8\u00b0 26' 50" and 8\u00b0 54' 23" south and longitudes 42\u00b0 19' 47" and 42\u00b0 45' 51" west. It falls within the municipal areas of [[S\u00e3o Raimundo Nonato]], [[S\u00e3o Jo\u00e3o do Piau\u00ed]], [[Coronel Jos\u00e9 Dias]] and [[Canto do Buriti]]. It has an area of 1291.4 square kilometres (319,000 acres). The area has the largest concentration of prehistoric small farms on the American continents. Scientific studies confirm that the Capivara mountain range was densely populated in prehistoric periods.\n\n[[Cueva de las Manos]] (Spanish for "Cave of the Hands") is a cave located in the [[provinces of Argentina|province]] of [[Santa Cruz Province, Argentina|Santa Cruz]], [[Argentina]], 163 km (101 mi) south of the town of [[Perito Moreno, Santa Cruz|Perito Moreno]], within the borders of the [[Francisco P. Moreno National Park]], which includes many sites of [[archaeology|archaeological]] and [[paleontology|paleontological]] importance.\n\nThe hand images are often negative ([[stencil]]led). Besides these there are also depictions of human beings, [[guanaco]]s, [[rhea (bird)|rheas]], [[felidae|felines]] and other animals, as well as [[geometry|geometric]] shapes, [[zigzag]] patterns, representations of the sun, and [[hunting]] scenes. Similar paintings, though in smaller numbers, can be found in nearby caves. There are also red dots on the ceilings, probably made by submerging their hunting [[bolas]] in ink, and then throwing them up. The colours of the paintings vary from red (made from [[hematite]]) to white, black or yellow. The negative hand impressions date to around 550 BC, the positive impressions from 180 BC, while the hunting drawings are calculated to more than 10,000 years old.<ref name=comte_indigarg>{{cite book |last=Le Comte |first=Christian |title=Argentine Indians |year=2003 |publisher=Consorcio de Editores |isbn=987-9479-11-4 |url=https://archive.org/details/argentineindians00chri }}</ref>  Most of the hands are left hands,<ref name=":9">{{cite book|last1=Podest\u00e1|first1=Mar\u00eda Mercedes|url=https://www.google.co.uk/books/edition/El_arte_rupestre_de_Argentina_ind%C3%ADgena/NuG-pvgnd6IC?hl=en&gbpv=1&dq=%22Cueva+de+las+Manos%22+left+hand&pg=PA11&printsec=frontcover|title=El arte rupestre de Argentina ind\u00edgena: Patagonia|last2=Raffino|first2=Rodolfo A.|last3=Paunero|first3=Rafael Sebasti\u00e1n|last4=Rolandi|first4=Diana S.|publisher=Grupo Abierto Communicaciones|year=2005|isbn=978-987-1121-16-8|language=es|access-date=2021-03-01|archive-url=https://web.archive.org/web/20211029010950/https://www.google.co.uk/gen_204?s=web&t=aft&atyp=csi&ei=10l7Ye-DE4K60PEP6uey8A8&rt=wsrt.491,aft.4960,prt.2585&imn=26&ima=10&imad=9&aftp=18869&bl=TGeo|archive-date=2021-10-29|url-status=live}}</ref><ref>{{Cite book|last1=Steele|first1=James|title=Stone Knapping: the Necessary Conditions for a Uniquely Hominin Behaviour|last2=Uomini|first2=Natalie|date=2005|publisher=McDonald Institute for Archaeological Research, University of Cambridge|isbn=1-902937-34-1|editor-last=Roux|editor-first=Valentine|location=Cambridge, UK|page=234|chapter=Humans, tools and handedness|oclc=64118071|access-date=2021-04-23|editor-last2=Bril|editor-first2=Blandine|chapter-url=https://www.ucl.ac.uk/~tcrnjst/Steele%26Uomini2005.pdf|archive-url=https://web.archive.org/web/20211016025838/https://www.ucl.ac.uk/~tcrnjst/Steele%26Uomini2005.pdf|archive-date=2021-10-16|url-status=live}}</ref> which suggests that painters held the spraying pipe with their right hand.<ref name=":2">{{cite magazine|last=Parfit|first=Michael|date=December 2000|title=Hunt for the First Americans|magazine=[[National Geographic]]|publisher=[[National Geographic Society]]|volume=198|issue=6|page=40}}</ref><ref name=":23">{{Cite book|last=Wiesner-Hanks|first=Merry E.|title=A Concise History of the World|date=September 23, 2015|publisher=[[Cambridge University Press]]|isbn=978-1-107-02837-1|location=New York|pages=11\u201313|oclc=908262350|author-link=Merry Wiesner-Hanks}}</ref><ref>{{Cite book|last=Moore|first=Jerry D.|title=Incidence of travel: recent journeys in ancient South America|date=2017|publisher=[[University Press of Colorado]]|isbn=978-1-60732-600-7|location=Boulder|page=100|doi=10.5876/9781607326007|jstor=j.ctt1m3210q|lccn=2016053403|oclc=973325343}}</ref>\n\n There are rock paintings in caves in Thailand, Malaysia, Indonesia, and Burma. In [[Thailand]], caves and scarps along the Thai-Burmese border, in the Petchabun Range of Central Thailand, and overlooking the Mekong River in Nakorn Sawan Province, all contain galleries of rock paintings. In [[Malaysia]], the [[Tambun rock art]] is dated at 2000 years, and those in the Painted Cave at [[Niah Caves]] National Park are 1200 years old. The anthropologist [[Ivor Hugh Norman Evans]] visited Malaysia in the early 1920s and found that some of the tribes (especially Negritos) were still producing cave paintings and had added depictions of modern objects including what are believed to be automobiles.<ref>{{cite web |last=Weber |first=George |url=http://www.andaman.org/BOOK/chapter35/text35.htm |work=The Negrito of Malaysia |title=The Semang |access-date=11 May 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130724065848/http://andaman.org/BOOK/chapter35/text35.htm |archive-date=24 July 2013 }}</ref> (See [[prehistoric Malaysia]].)\n\n {{Div col}}\n* [[Art of the Upper Paleolithic]]\n* [[List of Stone Age art]]\n* [[Petroglyph]]\n* [[Prehistoric art]]\n* [[Rock art]]\n{{div col end}}\n\n {{Notelist}}\n\n {{Reflist}}\n\n * {{Cite book |first=Mark |last=Dubowski |title=Discovery in the Cave (Children's early reader) |publisher=[[Random House]] |location=New York, USA |year=2010 |isbn=978-0-375-85893-2 |url-access=registration |url=https://archive.org/details/discoveryincave0000dubo }}\n* {{cite book|last=Fage|first=Luc-Henri|title=Borneo \u2013 Memory of the Caves|year=2010|publisher=Le Kalimanthrope|isbn=978-2-9536616-1-3|author2=Chazine, Jean-Michel}}\n* {{cite book|editor1-last=Heyd|editor1-first=Thomas |editor2-last=Clegg |editor2-first=John |title=Aesthetics and Rock Art|publisher=Ashgate Publishing|year=2005|isbn=0-7546-3924-X}}\n* {{cite book |last=Curtis |first=Gregory |title=The Cave Painters: Probing the Mysteries of the World's First Artists |publisher=Knopf |year=2006 |isbn=1-4000-4348-4 |url=https://archive.org/details/cavepaintersprob00curt }}\n* {{cite journal |last=Nechvatal |first=Joseph |author-link=Joseph Nechvatal |title=Immersive Excess in the Apse of Lascaux |journal=Technonoetic Arts |volume=3 |issue=3 |year=2005 |pages=181\u2013192 |doi=10.1386/tear.3.3.181/1}}\n\n {{Commons category|Cave paintings}}\n{{Wiktionary}}\n\n*[http://www.bradshawfoundation.com/ Bradshaw Foundation] The recording of cave paintings around the world\n*[http://www.europreart.net/ EuroPreArt] database of European Prehistoric Art\n*[https://arara.wildapricot.org/ American Rock Art Research Association]\n*[http://news.bbc.co.uk/2/hi/7509683.stm Tour of Afghan cave paintings] from BBC News.\n*[http://www.kalimanthrope.com/ Le Kalimanthrope] Rock art of Borneo (Kalimantan, Indonesia)\n*[https://web.archive.org/web/20130622013211/https://sites.google.com/site/journeythrougharthistory/prehistoricart Journey through Art History], an outline of prehistoric art with emphasis on cave paintings from around the world.\n*[http://humanorigins.si.edu/evidence/human-evolution-timeline-interactive Human Timeline (Interactive)] \u2013 [[Smithsonian Institution|Smithsonian]], [[National Museum of Natural History]] (August 2016).\n\n{{Caves}}\n{{Prehistoric technology|state=collapsed}}\n{{Human Evolution}}\n{{portal bar|Evolutionary biology}}\n{{Subterranea}}\n{{Authority control}}", "Cave painting --- Introduction ---|Dating": "[[File:Lubang Jeriji Sal\u00e9h cave painting of Bull.jpg|thumb|One of the oldest known [[Figurative art|figurative paintings]], a depiction of an unknown [[Bovinae|bovine]], was discovered in the [[Lubang Jeriji Sal\u00e9h]] cave and dated to be more than 40,000 (perhaps as old as 52,000) years old.<ref name="NYT-20181107-cz" /><ref name="NAT-20181107" />]]\n\nNearly 350 caves have now been discovered in France and Spain that contain art from prehistoric times. Initially, the age of the paintings had been a contentious issue, since methods like [[radiocarbon dating]] can produce misleading results if contaminated by other samples,<ref name=welsh>{{cite book|last=Welsh|first=Liz|title=Rock-art of the Southwest: a Visitor's Companion|year=2000|publisher=Wilderness Press|location=Berkeley, California|isbn=0-89997-258-6|edition=1st|author2=Welsh, Peter|page=62}}</ref> and caves and rocky overhangs (where [[parietal art]] is found) are typically littered with debris from many time periods. But subsequent technology has made it possible to date the paintings by sampling the pigment itself, torch marks on the walls,<ref name=valladas>{{cite journal|last=Valladas|first=Helene|title=Direct radiocarbon dating of prehistoric cave paintings by accelerator mass spectrometry|journal=Measurement Science and Technology|date=1 September 2003|volume=14|issue=9|pages=1487\u20131492|doi=10.1088/0957-0233/14/9/301}}</ref> or the formation of carbonate deposits on top of the paintings.<ref name="Hoffmann, D.L. 2016. pp.104-119">{{cite journal | last1 = Hoffmann | first1 = D.L. | last2 = Pike | first2 = A.W. | last3 = Garc\u00eda-Diez | first3 = M. | last4 = Pettitt | first4 = P.B. | last5 = Zilh\u00e3o | first5 = J. | year = 2016 | title = Methods for U-series dating of CaCO3 crusts associated with Palaeolithic cave art and application to Iberian sites | url = https://eprints.soton.ac.uk/402243/1/Hoffmann%2520et%2520al_accepted.docx| journal = Quaternary Geochronology | volume = 36 | pages = 104\u2013119 | doi = 10.1016/j.quageo.2016.07.004 }}</ref> The subject matter can also indicate chronology: for instance, the [[reindeer]] depicted in the Spanish cave of Cueva de las Monedas places the drawings in the last Ice Age.\n\nThe oldest known cave painting is a red hand stencil in [[Cave of Maltravieso|Maltravieso cave]], [[C\u00e1ceres, Spain|C\u00e1ceres]], Spain. It has been dated using the uranium-thorium method<ref name="Hoffmann, D.L. 2016. pp.104-119"/> to older than 64,000 years and was made by a [[Neanderthal]].<ref name=Hoffmann2018/> The oldest date given to an animal cave painting is now a depiction of several human figures hunting pigs in the [[caves in the Maros-Pangkep karst]] of [[South Sulawesi]], [[Indonesia]], dated to be over 43,900 years old.<ref name="NYT-20191211"/> Before this, the oldest known figurative cave paintings were that of a bull dated to 40,000 years, at [[Lubang Jeriji Sal\u00e9h]] cave, [[East Kalimantan]], [[Borneo]],<ref>Aubert, M. et al [https://www.nature.com/articles/s41586-018-0679-9 Palaeolithic cave art in Borneo] // Nature (2018)</ref> and a depiction of a pig with a minimum age of 35,400 years at Timpuseng cave in Sulawesi.<ref name=Aubert2014/>\n\nThe earliest known European figurative cave paintings are those of [[Chauvet Cave]] in France, dating to earlier than 30,000 BCin the [[Upper Paleolithic]] according to [[radiocarbon]] dating.<ref>{{cite web |last=Clottes |first=Jean |url=http://www.metmuseum.org/toah/hd/chav/hd_chav.htm |title=Chauvet Cave (ca. 30,000 B.C.) |work=Heilbrunn Timeline of Art History |publisher=The Metropolitan Museum of Art |location=New York |date=October 2002 |access-date=11 May 2013}}</ref> Some researchers believe the drawings are too advanced for this era and question this age.<ref>{{cite journal|last=Pettitt|first=Paul|title=Art and the Middle-to-Upper Paleolithic transition in Europe: Comments on the archaeological arguments for an early Upper Paleolithic antiquity of the Grotte Chauvet art|journal=Journal of Human Evolution|date=1 November 2008 |volume=55 |issue=5 |pages=908\u2013917 |doi=10.1016/j.jhevol.2008.04.003 |pmid=18678392}}</ref> However, more than 80 radiocarbon dates had been obtained by 2011, with samples taken from torch marks and from the paintings themselves, as well as from animal bones and charcoal found on the cave floor. The radiocarbon dates from these samples show that there were two periods of creation in Chauvet: 35,000 years ago and 30,000 years ago. One of the surprises was that many of the paintings were modified repeatedly over thousands of years, possibly explaining the confusion about finer paintings that seemed to date earlier than cruder ones.<ref>{{cite journal |last=Zorich |first=Zach |title=A Chauvet Primer |journal=Archaeology |volume=64 |issue=2 |date=March\u2013April 2011 |page=39 |url=http://archive.archaeology.org/1103/features/werner_herzog_chauvet_cave_primer.html}}</ref> \n[[File:Rhinos Chauvet Cave.jpg|thumb|left|An artistic depiction of a group of rhinoceros, was completed in the [[Chauvet Cave]] 30,000 to 32,000 years ago.]]\nIn 2009, [[Caving|cavers]] discovered drawings in [[Coliboaia Cave]] in Romania, stylistically comparable to those at Chauvet.<ref name=Coliboaia_Ghemis>{{cite journal |last=Ghemis |first=Calin|author2=Clottes, J. |author3=Gely, B. |author4= Prudhomme, F. |title=An Exceptional Archaeological Discovery \u2013 the "Art Gallery" in Coliboaia Cave |journal=Acta Archaeologica Carpathica |year=2011 |volume=XLVI |url=https://www.academia.edu/1488865 |access-date=7 March 2013 |issn=0001-5229}}</ref> An initial dating puts the age of an image in the same range as Chauvet: about 32,000 years old.<ref name=Coliboaia_Zorich>{{cite journal|last=Zorich|first=Zach|title=From the Trenches \u2013 Drawing Paleolithic Romania|journal=Archaeology|date=January\u2013February 2012|volume=65|issue=1|url=http://archive.archaeology.org/1201/trenches/coliboaia_cave_romania_charcoal_drawings.html|access-date=7 March 2013}}</ref>\n\nIn Australia, cave paintings have been found on the [[Arnhem Land]] plateau showing [[megafauna]] which are thought to have been extinct for over 40,000 years, making this site another candidate for oldest known painting; however, the proposed age is dependent on the estimate of the extinction of the species seemingly depicted.<ref name=abc_megafauna>{{cite web|last=Masters|first=Emma|title=Megafauna cave painting could be 40,000 years old|url=http://www.abc.net.au/news/2010-05-31/megafauna-cave-painting-could-be-40000-years-old/847564|publisher=Australian Broadcasting Commission (ABC)|access-date=30 December 2012|date=May 31, 2010}}</ref>  Another Australian site, [[Gabarnmung|Nawarla Gabarnmang]], has charcoal drawings that have been radiocarbon-dated to 28,000 years, making it the oldest site in Australia and among the oldest in the world for which reliable date evidence has been obtained.<ref name=CSM_rockart>{{cite news|last=McGuirk|first=Rod|title=Australian rock art among the world's oldest|url=http://www.csmonitor.com/Science/2012/0618/Australian-rock-art-among-world-s-oldest|access-date=30 December 2012|newspaper=Christian Science Monitor|date=June 18, 2012|agency=AP}}</ref>\n\nOther examples may date as late as the Early Bronze Age, but the well-known [[Magdalenian]] style seen at [[Lascaux]] in France (c.{{space}}15,000 BC) and [[Cave of Altamira|Altamira]] in Spain died out about 10,000{{space}}BC, coinciding with the advent of the [[Neolithic period]].  Some caves probably continued to be painted over a period of several thousands of years.<ref name=telegraph_20000>{{cite news|last=Gray|first=Richard|title=Prehistoric cave paintings took up to 20,000 years to complete|url=https://www.telegraph.co.uk/earth/3352850/Prehistoric-cave-paintings-took-up-to-20000-years-to-complete.html|archive-url=https://web.archive.org/web/20090615073824/http://www.telegraph.co.uk/earth/3352850/Prehistoric-cave-paintings-took-up-to-20000-years-to-complete.html|url-status=dead|archive-date=15 June 2009|access-date=30 December 2012|newspaper=The Telegraph|date=5 October 2008}}</ref>\n\nThe next phase of surviving European prehistoric painting, the [[rock art of the Iberian Mediterranean Basin]], was very different, concentrating on large assemblies of smaller and much less detailed figures, with at least as many humans as animals.  This was created roughly between 10,000 and 5,500 years ago, and painted in rock shelters under cliffs or shallow caves, in contrast to the recesses of deep caves used in the earlier (and much colder) period.  Although individual figures are less naturalistic, they are grouped in coherent grouped compositions to a much greater degree.", "Cave painting --- Introduction ---|Subjects, themes, and patterns in cave painting": "[[File:Rock art bull.jpg|thumb|Prehistoric cave painting of animals at Albarrac\u00edn, Teruel, Spain ([[rock art of the Iberian Mediterranean Basin]])]]\n\nCave artists use a variety of techniques such as finger tracing, modeling in clay, engravings, bas-relief sculpture, hand stencils, and paintings done in two or three colors. Scholars classify cave art as "Signs" or abstract marks. \n<ref>{{cite book |last1=Renfrew |first1=Colin |title=Archaeology Theories, Methods and Practice |publisher=Thames and Hudson |edition=7th}}</ref>  The most common subjects in cave paintings are large wild animals, such as [[bison]], [[horse]]s, [[aurochs]], and [[deer]], and tracings of human hands as well as abstract patterns, called [[finger flutings]]. The species found most often were suitable for hunting by humans, but were not necessarily the actual typical prey found in associated deposits of bones; for example, the painters of Lascaux have mainly left reindeer bones, but this species does not appear at all in the cave paintings, where [[equine]] species are the most common.  Drawings of humans were rare and are usually schematic as opposed to the more detailed and naturalistic images of animal subjects. Kieran D. O'Hara, geologist, suggests in his book ''Cave Art and Climate Change'' that climate controlled the themes depicted.<ref>O'Hara, K. (2014). Cave Art and Climate Change, Archway Publishing.</ref>\nPigments used include red and yellow [[ochre]], [[hematite]], [[manganese oxide]] and [[charcoal]]. Sometimes the silhouette of the animal was incised in the rock first, and in some caves all or many of the images are only engraved in this fashion,{{citation needed|date=April 2021}} taking them somewhat out of a strict definition of "cave painting".\n\nSimilarly, large animals are also the most common subjects in the many small carved and engraved bone or ivory (less often stone) pieces dating from the same periods.  But these include the group of [[Venus figurine]]s, which have no real equivalent in cave paintings.{{citation needed|date=December 2012}}\n\nHand stencils, formed by placing a hand against the wall and covering the surrounding area in pigment result in the characteristic image of a roughly round area of solid pigment with the uncoloured shape of the hand in the centre, these may then be decorated with dots, dashes, and patterns. Often, these are found in the same caves as other paintings, or may be the only form of painting in a location. Some walls contain many hand stencils.  Similar hands are also painted in the usual fashion. A number of hands show a finger wholly or partly missing, for which a number of explanations have been given. Hand images are found in similar forms in Europe, Eastern Asia and South America.<ref>{{cite web|url=http://www.bradshawfoundation.com/hands/|title=Hand Paintings and Symbols in Rock Art|first=Bradshaw|last=Foundation|work=bradshawfoundation.com}}</ref>\n\n [[File:Bestias11.JPG|thumb|Rock paintings from the [[Cave of Beasts]] ([[Gilf Kebir]], [[Libyan Desert]]) Estimated 7000 [[Before Present|BP]] ]]\nIn the early 20th century, following the work of [[Walter Baldwin Spencer]] and [[Francis James Gillen]], scholars such as [[Salomon Reinach]], [[Henri Breuil]] and {{Ill|Henri Begou\u00ebn|lt=Count B\u00e9gou\u00ebn|fr}} interpreted the paintings as 'utilitarian' [[hunting magic]] to increase the abundance of prey.<ref>{{Cite web|date=9 December 2019|title=Hunting magic in rock art|url=https://bradshawfoundation.com/news/rock_art.php?id=Hunting-magic-in-rock-art|access-date=2021-05-25|website=Bradshaw Foundation}}</ref> [[Jacob Bronowski]] states, "I think that the power that we see expressed here for the first time is the power of anticipation: the forward-looking imagination. In these paintings the hunter was made familiar with dangers which he knew he had to face but to which he had not yet come."<ref>{{Cite book|last=Bronowski|first=Jacob|url=http://archive.org/details/ascentofman0000bron_y1z2|title=The Ascent of Man|publisher=BBC Books|year=1990|isbn=978-0-563-20900-3|location=London|pages=54|orig-year=1973}}</ref>\n\nAnother theory, developed by [[David Lewis-Williams]] and broadly based on ethnographic studies of contemporary [[hunter-gatherer]] societies, is that the paintings were made by paleolithic [[Shamanism|shamans]].<ref>{{cite book|last=Whitley|first=David S.|title=Cave Paintings and the Human Spirit: The Origin of Creativity and Belief|year=2009|publisher= Prometheus|isbn= 978-1-59102-636-5|page=35}}</ref> The shaman would retreat into the darkness of the caves, enter into a trance state, then paint images of their visions, perhaps with some notion of drawing out power from the cave walls themselves.\n\nR. Dale Guthrie, who has studied both highly artistic and lower quality art and figurines, identifies a wide range of skill and age among the artists. He hypothesizes that the main themes in the paintings and other artifacts (powerful beasts, risky hunting scenes and the representation of women in the [[Venus figurines]]) are the work of adolescent males, who constituted a large part of the [[prehistoric demography|human population at the time]].<ref name=guthrie>{{cite book|last=Guthrie|first=R. Dale|title=The Nature of Paleolithic Art|year=2005|publisher=Univ. of Chicago Press|location=Chicago [u.a.]|isbn=978-0-226-31126-5|chapter=Preface: Reassembling the Bones |chapter-url=http://www.press.uchicago.edu/Misc/Chicago/311260.html |access-date=31 December 2012}}</ref>{{check|date=December 2012}} However, in analyzing hand prints and stencils in French and Spanish caves, Dean Snow of Pennsylvania State University has proposed that a proportion of them, including those around the spotted horses in Pech Merle, were of female hands.<ref name=times_handprints>{{cite news|last=Hammond|first=Norman|title=Cave painters' giveaway handprints at Pech-Merle|url=http://www.thetimes.co.uk/tto/life/courtsocial/article1818692.ece|access-date=31 December 2012|newspaper=The Times|date=September 11, 2009}}</ref>", "Cave painting --- Introduction ---|Paleolithic cave art by region": "{{see|Paleolithic art}}\n\n {{See also|Caves in Cantabria}}\n[[File:20,000 Year Old Cave Paintings Hyena.png|thumb|right|30,000-year-old [[cave hyena]] painting found in the [[Chauvet Cave]], France]]\n[[File:Cave of Altamira and Paleolithic Cave Art of Northern Spain-110113.jpg|thumb|[[Cave of Altamira and Paleolithic Cave Art of Northern Spain]]]]\nWell-known cave paintings include those of:\n* [[Cave of El Castillo]], Spain (~40.000 y.o.)\n*[[Kapova Cave]], [[Bashkortostan]], Russia (~36,000 y.o.)<ref>{{Cite web|url=http://u7a.ru/articles/society/11854|title=\u0411\u0430\u0448\u043a\u0438\u0440\u0438\u044f: \u043d\u043e\u0432\u044b\u0435 \u0438\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u043d\u0438\u044f "\u0441\u043e\u0441\u0442\u0430\u0440\u0438\u043b\u0438" \u043d\u0430\u0441\u043a\u0430\u043b\u044c\u043d\u044b\u0435 \u0440\u0438\u0441\u0443\u043d\u043a\u0438 \u041a\u0430\u043f\u043e\u0432\u043e\u0439 \u043f\u0435\u0449\u0435\u0440\u044b \u0432 \u0434\u0432\u0430 \u0440\u0430\u0437\u0430|website=u7a.ru|access-date=2019-10-11}}</ref>\n* [[Chauvet Cave]], near [[Vallon-Pont-d'Arc]], France (~35,000 y.o.)\n* [[Cave of La Pasiega]], [[Cuevas de El Castillo]], [[Cantabria]], Spain (~30,000 y.o.?)\n* [[Caves of Arcy-sur-Cure]], France (~28,200 y.o.)\n* [[Cosquer Cave]], with an entrance below [[sea level]] near [[Marseille, France]] (~27,000 y.o.)\n* [[Caves of Gargas]], France (~27,000 y.o.)\n* [[Grotte de Cussac]], France (~25,000 y.o.)\n* [[Pech Merle]], near [[Cabrerets]], France (25,000 y.o.)\n* [[Lascaux]], France (~17,000 y.o.)\n* [[Cave of Niaux]], France (~17,000 y.o.)\n* [[Font-de-Gaume]], in the [[Dordogne]] Valley, France (~17,000 y.o.)\n* [[Cave of Altamira]], near [[Santillana del Mar]], [[Cantabria]], Spain (~15,500 y.o.)\n* [[La Marche (cave)|La Marche]], in [[Lussac-les-Ch\u00e2teaux]],  France (~15,000 y.o.)\n* [[Les Combarelles]], in [[Les Eyzies-de-Tayac-Sireuil|Les Eyzies de Tayac]], [[Dordogne]], France (~13,600 y.o.)\n* [[Cave of the Trois-Fr\u00e8res]], in [[Ari\u00e8ge (department)|Ari\u00e8ge]], France (~13,000 y.o.)<ref>{{cite web |title=Trois Fr\u00e8res |url=https://www.britannica.com/place/Trois-Freres#ref=ref893311 |website=[[Encyclop\u00e6dia Britannica Online|Encyclop\u00e6dia Britannica]] |language=en |access-date=February 23, 2020}}</ref>\n* [[Magura Cave]], Bulgaria (~10,000 y.o.)\n\n[[File:Men of the old stone age (1915) Wolf.png|thumb|[[Polychrome]] cave painting of a [[wolf]], Font-de-Gaume, France]]\n\nOther sites include [[Creswell Crags]], [[Nottinghamshire]], England (~14,500 ys old cave etchings and [[bas-reliefs]] discovered in 2003), [[Pe\u0219tera Coliboaia]] in [[Romania]] (~29,000 y.o. art?).<ref>{{cite news |last=Tugman |first=Lindsey |url=http://www.thv11.com/news/article/171246/288/Oldest-cave-drawings-found-in-Romanian-cave |title=Oldest cave drawings found in Romanian cave |agency=CBS News |date=1 September 2011 |access-date=11 May 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130921063051/http://www.thv11.com/news/article/171246/288/Oldest-cave-drawings-found-in-Romanian-cave |archive-date=21 September 2013 }}</ref>\n\nRock painting was also performed on cliff faces; but fewer of those have survived because of [[erosion]]. One example is the rock paintings of [[Astuvansalmi]] (3000\u20132500 BC) in the [[Saimaa]] area of Finland.\n\nWhen [[Marcelino Sanz de Sautuola]] first encountered the [[Magdalenian]] paintings of the Cave of Altamira in Cantabria, Spain in 1879, the academics of the time considered them hoaxes. Recent reappraisals and numerous additional discoveries have since demonstrated their authenticity, while at the same time stimulating interest in the artistry and symbolism<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211205/hJnEQCMA5Sg Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20151218194343/https://www.youtube.com/watch?v=hJnEQCMA5Sg&gl=US&hl=en Wayback Machine]{{cbignore}}: {{cite web| url = https://www.youtube.com/watch?v=hJnEQCMA5Sg| title = Why are these 32 symbols found in caves all over Europe {{!}} Genevieve von Petzinger | website=[[YouTube]]}}{{cbignore}}</ref> of [[Upper Palaeolithic]] peoples.\n{{clear left}}\n\n [[File:Hands in Pettakere Cave DYK crop.jpg|alt=Cave of Pettakere, Bantimurung district (kecamatan), South Sulawesi, Indonesia. Hand stencils estimated between 0,000 years old<ref>{{cite journal | last1 = Aubert | first1 = M. | display-authors = etal | year = 2014| title = Pleistocene cave art from Sulawesi, Indonesia | journal = Nature | volume = 514 | issue = 7521| pages = 223\u2013227 | quote = using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. | doi = 10.1038/nature13422 | pmid = 25297435| bibcode = 2014Natur.514..223A | s2cid = 2725838 }}</ref>|thumb|[[Caves in the Maros-Pangkep karst]] ([[Sulawesi]], Indonesia). Hand stencils estimated between 35,000\u201340,000 [[Before Present|BP]], stencils of right hands shown.]]\n\nIn [[Indonesia]] the [[caves in the district of Maros]] in [[Sulawesi]] are famous for their hand prints. About 1,500 negative handprints have also been found in 30 painted caves in the Sangkulirang area of Kalimantan; preliminary dating analysis as of 2005 put their age in the range of 10,000 years old.<ref>{{cite journal|last=Chazine|first=J-M.|title=Rock Art, Burials, and Habitations: Caves in East Kalimantan |journal=Asian Perspectives |year=2005 |volume=44 |issue=1 |pages=219\u2013230 |doi=10.1353/asi.2005.0006 |hdl=10125/17232|s2cid=53372873|url=http://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/17232/AP-v44n1-219-230.pdf?sequence=1 |access-date=12 May 2013|hdl-access=free }}\n{{cite journal |last=Fage |first=Luc-Henri |title=Hands Across Time: Exploring the Rock Art of Borneo |journal=National Geographic |date=August 2005 |volume=208 |issue=2 |pages=44\u201345 |url=http://ngm.nationalgeographic.com/print/features/world/asia/indonesia/cave-art-text |access-date=7 October 2013}}</ref> A 2014 study based on [[uranium\u2013thorium dating]] dated a Maros hand stencil to a minimum age of 39,900 years. A painting of a [[babirusa]] was dated to at least 35.4 ka, placing it among the oldest known figurative depictions worldwide.<ref name=Aubert2014/>\n\nIn November 2018, scientists reported the discovery of the oldest known [[Figurative art|figurative art painting]], over 40,000 (perhaps as old as 52,000) years old, of an unknown animal, in the cave of [[Lubang Jeriji Sal\u00e9h]] on the [[Indonesia]]n island of [[Borneo]].<ref name="NYT-20181107-cz">{{cite news |last=Zimmer |first=Carl |author-link=Carl Zimmer |title=In Cave in Borneo Jungle, Scientists Find Oldest Figurative Painting in the World - A cave drawing in Borneo is at least 40,000 years old, raising intriguing questions about creativity in ancient societies. |url=https://www.nytimes.com/2018/11/07/science/oldest-cave-art-borneo.html |date=7 November 2018 |work=[[The New York Times]] |access-date=8 November 2018 }}</ref><ref name="NAT-20181107">{{cite journal |author=Aubert, M.|display-authors=et al |title=Palaeolithic cave art in Borneo |date=7 November 2018 |journal=[[Nature (journal)|Nature]] |doi=10.1038/s41586-018-0679-9 |pmid=30405242 |volume=564 |issue=7735 |pages=254\u2013257 |bibcode=2018Natur.564..254A |s2cid=53208538 }}</ref>\n\nAnd more recently, in 2021, archaeologists announced the discovery of cave art at least 45,500 years old in Leang Tedongnge cave, Indonesia. According to the journal ''[[Science Advances]]'', the cave painting of a warty pig is the earliest evidence of human settlement of the region.<ref>{{Cite web|last=France-Presse|first=Agence|date=2021-01-13|title=World's 'oldest known cave painting' found in Indonesia|url=http://www.theguardian.com/science/2021/jan/13/worlds-oldest-known-cave-painting-found-in-indonesia|access-date=2021-02-24|website=The Guardian|language=en}}</ref><ref>{{Cite news|date=2021-01-14 |title=Indonesia: Archaeologists find world's oldest animal cave painting |language=en-GB |work=BBC News |url=https://www.bbc.com/news/world-asia-55657257|access-date=2021-02-24}}</ref> It has been reported that it is rapidly deteriorating as a result of climate change in the region.<ref>{{Cite news|date=2021-05-19 |title=Indonesia: Climate change destroying world's oldest animal painting |language=en-GB |work=BBC News|url=https://www.bbc.com/news/world-asia-57166995|access-date=2021-05-19}}</ref>\n\nOriginating in the Paleolithic period, [[Khoit Tsenkher Cave Rock Art|the rock art found in Khoit Tsenkher Cave]], Mongolia, includes symbols and animal forms painted from the walls up to the ceiling.<ref>[https://whc.unesco.org/en/tentativelists/935/ Khoit tsenkher cave rock painting \u2013 UNESCO World Heritage Centre]</ref> Stags, buffalo, oxen, ibex, lions, Argali sheep, antelopes, camels, elephants, ostriches, and other animal pictorials are present, often forming a palimpsest of overlapping images. The paintings appear brown or red in color, and are stylistically similar to other Paleolithic rock art from around the world but are unlike any other examples in Mongolia.\n\nThe [[Padah-Lin Caves]] of [[Burma]] contain 11,000-year-old paintings and many rock tools.\n\n {{Main|Cave paintings in India}}\n[[File:Bhimbetka rock paintng1.jpg|thumb|right|[[Bhimbetka rock shelters|Bhimbetka]] rock painting]]\nThe [[Bhimbetka rock shelters]] exhibit the earliest traces of human life in India. Paintings in Bhimbetka are dated to about 8,000 BC.<ref>{{cite book |last1=Mathpal |first1=Yashodhar |title=Prehistoric Painting Of Bhimbetka |date=1984 |publisher=Abhinav Publications |isbn=9788170171935 |page=220 |url=https://books.google.com/books?id=GG7-CpvlU30C&pg=PA220 |language=en}}</ref><ref>{{cite book |last1=Tiwari |first1=Shiv Kumar |title=Riddles of Indian Rockshelter Paintings |date=2000 |publisher=Sarup & Sons |isbn=9788176250863 |page=189 |url=https://books.google.com/books?id=-jO0fvT4r9gC&pg=PA189 |language=en}}</ref><ref>{{cite book |title=Rock Shelters of Bhimbetka |date=2003 |publisher=UNESCO |page=16 |url=https://whc.unesco.org/uploads/nominations/925.pdf}}</ref><ref>{{cite book |last1=Mithen |first1=Steven |title=After the Ice: A Global Human History, 20,000 - 5000 BC |date=2011 |publisher=Orion |isbn=9781780222592 |page=524 |url=https://books.google.com/books?id=Uaxg_QDSsrQC&pg=PT524 |language=en}}</ref><ref>{{cite book |last1=Javid |first1=Ali |last2=J\u0101v\u012bd |first2=\u02bbAl\u012b |last3=Javeed |first3=Tabassum |title=World Heritage Monuments and Related Edifices in India |date=2008 |publisher=Algora Publishing |isbn=9780875864846 |page=19 |url=https://books.google.com/books?id=54XBlIF9LFgC&pg=PA19 |language=en}}</ref> Similar paintings are found in other parts of India as well. In Tamil Nadu, ancient Paleolithic Cave paintings are found in Kombaikadu, Kilvalai, Settavarai and Nehanurpatti. In Odisha they are found in Yogimatha and Gudahandi. In Karnataka, these paintings are found in Hiregudda near Badami. The most recent painting, consisting of geometric figures, date to the [[Middle Ages|medieval period]].\nExecuted mainly in red and white with the occasional use of green and yellow, the paintings depict the lives and times of the people who lived in the caves, including scenes of childbirth, communal dancing and drinking, religious rites and burials, as well as indigenous animals.<ref>{{cite web|url=https://whc.unesco.org/pg.cfm?cid=31&id_site=925|title=Rock Shelters of Bhimbetka|publisher=World Heritage Site|access-date=2009-12-22}}</ref>\n\n Cave paintings found at the [[Apollo 11 Cave]] in [[Namibia]] are estimated to date from approximately 25,500\u201327,500 years ago.<ref>{{cite web |url=http://www.metmuseum.org/toah/hd/apol/hd_apol.htm |title=Apollo 11 (ca. 25,500\u201323,500 B.C.) and Wonderwerk (ca. 8000 B.C.) Cave Stones |work=Heilbrunn Timeline of Art History |publisher=The Metropolitan Museum of Art |location=New York |date=October 2000 |access-date=11 May 2013}}</ref>\n\nIn 2011, archaeologists found a small rock fragment at [[Blombos Cave]], about {{convert|300|km|mi|abbr=on}} east of [[Cape Town]] on the southern cape coastline in [[South Africa]], among spear points and other excavated material. After extensive testing for seven years, it was revealed that the lines drawn on the rock were handmade and from an ochre crayon dating back 73,000 years. This makes it the oldest known rock painting.<ref name="NYT-20180912">{{cite news |last=St. Fleur |first=Nicholas|title=Oldest Known Drawing by Human Hands Discovered in South African Cave |url=https://www.nytimes.com/2018/09/12/science/oldest-drawing-ever-found.html |date=12 September 2018 |work=[[The New York Times]] |access-date=15 September 2018 }}</ref><ref>{{Cite web|url=https://www.theguardian.com/science/2018/sep/12/earliest-known-drawing-found-on-rock-in-south-african-cave|title=Earliest known drawing found on rock in South African cave|last=Sample|first=Ian|date=2018-09-12|website=The Guardian|language=en|access-date=2018-09-12}}</ref>\n\n [[Image:(1)Jabiru_dreaming-7.jpg|right|thumb|Painting at Jabiru Dreaming, Kakadu National Park]]\nSignificant early cave paintings, executed in [[ochre]], have been found in [[Kimberley (Western Australia)|Kimberley]] and [[Kakadu National Park|Kakadu]], Australia. Ochre is not an [[organic material]], so [[carbon dating]] of these pictures is often impossible. The oldest so far dated at 17,300 years is an ochre painting of a [[kangaroo]] in the [[Kimberley (Western Australia)|Kimberley]] region, which was dated by carbon dating wasp nest material underlying and overlying the painting.<ref>{{cite web |title=Australia: Oldest rock art is 17,300-year-old kangaroo |url=https://www.bbc.co.uk/news/world-australia-56164484 |website=BBC News |publisher=BBC|date=23 February 2021|access-date=25 February 2021}}</ref>  Sometimes the approximate date, or at least, an [[Epoch (reference date)|epoch]], can be surmised from the painting content, contextual artifacts, or organic material intentionally or inadvertently mixed with the inorganic ochre paint, including torch soot.<ref name=valladas />\n\nA red ochre painting, discovered at the centre of the [[Arnhem Land Plateau]], depicts two [[emu]]-like birds with their necks outstretched. They have been identified by a palaeontologist as depicting the [[megafauna]] species ''[[Genyornis]]'', giant birds thought to have become extinct more than 40,000 years ago; however, this evidence is inconclusive for dating.  It may suggest that Genyornis became extinct at a later date than previously determined.<ref name=abc_megafauna />\n\n[[Hook Island]] in the [[Whitsunday Islands National Park|Whitsunday Islands]] is also home to a number of cave paintings created by the seafaring [[Ngaro people]].<ref>{{cite web|title=Whitsunday national park islands - Nature, Culture and History|url=https://www.npsr.qld.gov.au/parks/parks-whitsundays/culture.html|website=Queensland Government|publisher=The State of Queensland (Department of National Parks, Sport and Racing)|access-date=16 October 2017}}</ref>", "Cave painting --- Introduction ---|Holocene cave art": "[[File:Dera rock art.jpg|thumb|Dera Rock Art in, [[Eritrea]]]]\n\n In the [[Philippines]] at [[Tabon Caves]] the oldest artwork may be a relief of a shark above the cave entrance. It was partially disfigured by a later jar burial scene.{{citation needed|date=August 2018}}\n\nThe [[Edakkal Caves]] of Kerala, India, contain drawings that range over periods from the Neolithic as early as 5,000 BC to 1,000 BC.<ref>{{cite news|url=http://newindianexpress.com/cities/thiruvananthapuram/article142152.ece |title='Edakkal cave findings related to Indus Valley civilization |newspaper=The New Indian Express |date=2009-10-22 |access-date=2012-08-17}}</ref><ref>{{cite web|url=https://www.scribd.com/doc/26510292/Sarasvati-River-Indus-Script-Ancient-Village-Or |title=Sarasvati River Indus Script Ancient Village Or |publisher=Scribd.com |access-date=2012-08-17}}</ref><ref>{{cite news|url=http://www.hindustantimes.com/Symbols-akin-to-Indus-valley-culture-discovered/Article1-459163.aspx |title=Symbols akin to Indus valley culture discovered |newspaper=Hindustan Times |date=2009-09-29 |access-date=2012-08-17 |url-status=dead |archive-url=https://web.archive.org/web/20110128222211/http://www.hindustantimes.com/Symbols-akin-to-Indus-valley-culture-discovered/Article1-459163.aspx |archive-date=2011-01-28 }}</ref>\n\n [[File:Kohaito, grotta di adi alauti con pitture rupestri databili al 2500 ac ca. 36 dromedari.JPG|thumb|Rock art in the Adi Alauti cave, [[Eritrea]]]]\n[[File:Laas Geel.jpg|thumb|Cave paintings at the [[Laas Geel]] complex in northern [[Somaliland]].]]\n[[Rock art]] near Qohaito appears to indicate habitation in the area since the [[fifth millennium BC]], while the town is known to have survived to the sixth century AD. Mount [[Emba Soira]], Eritrea's highest mountain, lies near the site, as does a small successor village. Much of the rock art sites are found together with evidence of prehistoric stone tools, suggesting that the art could predate the widely presumed pastoralist and domestication events that occurred 5000\u2013 4000 years ago.<ref>{{Cite web|last=Admin|title=Understanding Rock Art in Eritrea|url=http://www.madote.com/2017/04/understanding-rock-art-in-eritrea.html|access-date=2021-02-16|website=Madote}}</ref><ref>{{Cite web|last=Centre|first=UNESCO World Heritage|title=Qoahito Cultural Landscape|url=https://whc.unesco.org/en/tentativelists/5600/|access-date=2021-02-16|website=UNESCO World Heritage Centre|language=en}}</ref>\n\nIn 2002, a French archaeological team discovered the [[Laas Geel]] cave paintings on the outskirts of [[Hargeisa]] in [[Somaliland]]. Dating back around 5,000 years, the paintings depict both wild animals and decorated cows. They also feature herders, who are believed to be the creators of the rock art.<ref name="Bakano">{{cite news|last=Bakano|first=Otto|url=https://www.google.com/hostednews/afp/article/ALeqM5jMNd90UAafsRNEDPyelL7Hee1ydw?docId=CNG.82196a5b15ef45a2d4e744675740cd6a.6e1 |title=Grotto galleries show early Somali life |agency=AFP |date=April 24, 2011|access-date=11 May 2013}}</ref> In 2008, Somali archaeologists announced the discovery of other cave paintings in [[Dhambalin]] region, which the researchers suggest includes one of the earliest known depictions of a hunter on horseback. The rock art is dated to 1000 to 3000 BC.<ref name="Tdodras">{{cite journal|last=Mire|first=Sada|title=The Discovery of Dhambalin Rock Art Site, Somaliland|journal=African Archaeological Review|year=2008|volume=25|issue=3\u20134|pages=153\u2013168|url=http://www.mbali.info/doc494.htm|access-date=22 June 2013|doi=10.1007/s10437-008-9032-2|s2cid=162960112|url-status=dead|archive-url=https://web.archive.org/web/20130627100400/http://www.mbali.info/doc494.htm|archive-date=27 June 2013}}</ref><ref name="Guafcpaonas">{{cite news|last=Alberge|first=Dalya|title=UK archaeologist finds cave paintings at 100 new African sites|url=https://www.theguardian.com/world/2010/sep/17/cave-paintings-found-in-somaliland|access-date=25 June 2013|newspaper=The Guardian|date=17 September 2010}}</ref>\n\nAdditionally, between the towns of [[Las Khorey]] and [[El Ayo]] in [[Karinhegane]] is a site of numerous cave paintings of real and mythical animals. Each painting has an inscription below it, which collectively have been estimated to be around 2,500 years old.<ref name="Mheah">{{cite book|last=Hodd|first=Michael|title=East African Handbook|year=1994|publisher=Trade & Travel Publications|isbn=0-8442-8983-3|page=640|url=https://books.google.com/books?id=bL8tAQAAIAAJ}}</ref><ref name="Astgi">{{cite book|last=Ali|first=Ismail Mohamed|title=Somalia Today: General Information|year=1970|publisher=Ministry of Information and National Guidance, Somali Democratic Republic|page=295|url=https://books.google.com/books?id=tMVAAAAAYAAJ}}</ref> Karihegane's rock art is in the same distinctive style as the Laas Geel and Dhambalin cave paintings.<ref name="Iodn">{{cite book|last=Istituto universitario orientale (Naples, Italy)|title=Annali: Supplemento, Issues 70-73|year=1992|publisher=Istituto orientale di Napoli|page=57|url=https://www.google.com/books?id=DbhiAAAAMAAJ}}</ref><ref name="Crasos">{{cite web|title=Rock Art Sites of Somaliland|url=http://archive.cyark.org/rock-art-sites-of-somaliland-info|publisher=CyArk|access-date=28 March 2014|archive-url=https://web.archive.org/web/20140329002706/http://archive.cyark.org/rock-art-sites-of-somaliland-info|archive-date=29 March 2014|url-status=dead}}</ref> Around 25 miles from Las Khorey is found [[Gelweita]], another key rock art site.<ref name="Astgi" />\n\nIn [[Djibouti]], rock art of what appear to be antelopes and a giraffe are also found at [[Dorra]] and [[Balho]].<ref name="Amvjaa">{{citation |author=Universit\u00e4t Frankfurt am Main|journal=[[Journal of African Archaeology]] |title=Volumes 1\u20132 |date=2003|publisher=Africa Manga Verlag|page=230|url=https://www.google.com/books?id=ExwkAQAAIAAJ|access-date=7 September 2014}}</ref>\n\n [[File:Tassili - catapulte?.jpg|thumb|right|Cave painting at the [[Tassili n'Ajjer]] UNESCO World Heritage Site in southeast [[Algeria]].]]\nMany cave paintings are found in the [[Tassili n'Ajjer]] mountains in southeast [[Algeria]]. A [[UNESCO World Heritage Site]], the rock art was first discovered in 1933 and has since yielded 15,000 engravings and drawings that keep a record of the various animal migrations, climatic shifts, and change in human inhabitation patterns in this part of the Sahara from 6000 BC to the [[Classical antiquity#Roman Empire|late classical period]].<ref name=tassili>{{cite web|title=Tassili n'Ajjer|url=https://whc.unesco.org/en/list/179|publisher=UNESCO World Heritage Center|access-date=31 December 2012}}</ref> Other cave paintings are also found at the [[Akakus]], [[Mesak Settafet]] and [[Tadrart Acacus|Tadrart]] in [[Libya]] and other Sahara regions including: Ayr mountains, Niger and Tibesti, Chad.\n\nThe [[Cave of Swimmers]] and the [[Cave of Beasts]] in southwest [[Egypt]], near the border with Libya, in the mountainous [[Gilf Kebir]] region of the [[Sahara Desert]]. The Cave of Swimmers was discovered in October 1933 by the [[Hungary|Hungarian]] explorer [[L\u00e1szl\u00f3 Alm\u00e1sy]]. The site contains [[rock painting]] images of people swimming, which are estimated to have been created 10,000 years ago during the time of the most recent Ice Age.\n\nIn 2020, [[Solutional cave|limestone cave]] decorated with scenes of animals such as [[donkey]]s, [[camel]]s, [[deer]], [[mule]] and [[mountain goat]]s was uncovered in the area of Wadi Al-Zulma by the archaeological mission from the Tourism and Antiquities Ministry. Rock art cave is 15 meters deep and 20 meters high.<ref>{{Cite web|title=Ancient cave with distinguished engravings depicting scenes of animals discovered in Sinai - Ancient Egypt - Heritage|url=http://english.ahram.org.eg/NewsContent/9/40/368014/Heritage/Ancient-Egypt/Ancient-cave-with-distinguished-engravings-depicti.aspx|access-date=2020-09-09|website=Ahram Online|language=en}}</ref><ref>{{Cite web|date=2020-04-26|title=Photos: Archaeologists uncover ancient cave in North Sinai|url=https://egyptindependent.com/photos-archaeologists-uncover-ancient-cave-in-north-sinai/|access-date=2020-09-09|website=Egypt Independent|language=en-US}}</ref>\n\n [[File:Southafrica468bushman.jpg|thumb|right|[[San rock art|San rock paintings]] from the [[Western Cape]] in [[South Africa]].]]\nAt [[uKhahlamba / Drakensberg Park]], [[South Africa]], now thought to be some 3,000 years old, the paintings by the [[San people]] who settled in the area some 8,000 years ago depict animals and humans, and are thought to represent religious beliefs. Human figures are much more common in the rock art of Africa than in Europe.<ref>{{cite news |first=Leon |last=Jaroff |title=Etched in Stone |url=http://www.time.com/time/printout/0,8816,986446,00.html |archive-url=https://archive.today/20130204205110/http://www.time.com/time/printout/0,8816,986446,00.html |url-status=dead |archive-date=February 4, 2013 |work=Time |date=1997-06-02 |access-date=2008-10-07 |quote=Wildlife and humans tend to get equal billing in African rock art. (In the caves of western Europe, by contrast, pictures of animals cover the walls and human figures are rare.) In southern Africa, home to the San, or Bushmen, many of the rock scenes depicting people interpret the rituals and hallucinations of the shamans who still dominate the San culture today. Among the most evocative images are those believed to represent shamans deep in trance: a reclining, antelope-headed man surrounded by imaginary beasts, for example, or an insect-like humanoid covered with wild decorations.}}</ref>\n\n [[File:2009 07 09 camino cielo paradise 137.jpg|thumb|right|Painted Cave, [[Santa Barbara County, California]]]]\n\n{{Main|Great Mural Rock Art}}\nDistinctive monochrome and polychrome cave paintings and murals exist in the mid-peninsula regions of southern [[Baja California]] and northern [[Baja California Sur]], consisting of [[Pre-Columbian era|Pre-Columbian]] paintings of humans, land animals, sea creatures, and abstract designs. These paintings are mostly confined to the sierras of this region, but can also be found in outlying mesas and rock shelters. According to recent [[Radiocarbon dating|radiocarbon]] studies of the area, of materials recovered from archaeological deposits in the rock shelters and on materials in the paintings themselves, suggest that the Great Murals may have a time range extending as far back as 7,500 years ago.<ref>{{Cite web|url=http://news.nationalgeographic.com/news/2003/07/0717_030717_bajarockart.html|title=Baja California Rock Art Dated to 7,500 Years Ago|website=news.nationalgeographic.com|access-date=2016-03-29}}</ref>{{Further|Rock art of the Chumash people}}\n\nNative artists in the [[Chumash people|Chumash]] tribes created [[Rock art of the Chumash people|cave paintings]] that are located in present-day [[Santa Barbara, California|Santa Barbara]], [[Ventura County, California|Ventura]], and [[San Luis Obispo County, California|San Luis Obispo Counties]] in Southern [[California]] in the [[United States]]. They include examples at [[Burro Flats Painted Cave]] and [[Chumash Painted Cave State Historic Park, California|Chumash Painted Cave State Historic Park]].\n\nThere are also [[Native Americans in the United States|Native American]] [[pictogram]] examples in caves of the [[Southwestern United States]].  Cave art that is 6,000 years old was found in the [[Cumberland Plateau]] region of [[Tennessee]].<ref>{{Cite journal|title=Sacred landscapes of the south-eastern USA: prehistoric rock and cave art in Tennessee |author1 = Simekm Jan F. |author2 =Alan Cressler |author3 =Nicholas P. Herrmann |author4 =Sarah C. Sherwood|year=2013|journal=Antiquity |volume=87|issue=336 |pages=430\u2013446|doi=10.1017/S0003598X00049048 }}</ref>\n\n [[File:Serra da Capivara - Several Paintings 2b.jpg|thumb|Cave painting at Serra da Capivara National Park, [[Brazil]]]]\n[[Serra da Capivara National Park]] is a [[national park]] in the north east of Brazil with many prehistoric paintings; the park was created to protect the prehistoric artifacts and paintings found there. It became a [[World Heritage Site]] in 1991. Its best known archaeological site is [[Pedra Furada Site|Pedra Furada]].\n\nIt is located in northeast state of [[Piau\u00ed]], between latitudes 8\u00b0 26' 50" and 8\u00b0 54' 23" south and longitudes 42\u00b0 19' 47" and 42\u00b0 45' 51" west. It falls within the municipal areas of [[S\u00e3o Raimundo Nonato]], [[S\u00e3o Jo\u00e3o do Piau\u00ed]], [[Coronel Jos\u00e9 Dias]] and [[Canto do Buriti]]. It has an area of 1291.4 square kilometres (319,000 acres). The area has the largest concentration of prehistoric small farms on the American continents. Scientific studies confirm that the Capivara mountain range was densely populated in prehistoric periods.\n\n[[Cueva de las Manos]] (Spanish for "Cave of the Hands") is a cave located in the [[provinces of Argentina|province]] of [[Santa Cruz Province, Argentina|Santa Cruz]], [[Argentina]], 163 km (101 mi) south of the town of [[Perito Moreno, Santa Cruz|Perito Moreno]], within the borders of the [[Francisco P. Moreno National Park]], which includes many sites of [[archaeology|archaeological]] and [[paleontology|paleontological]] importance.\n\nThe hand images are often negative ([[stencil]]led). Besides these there are also depictions of human beings, [[guanaco]]s, [[rhea (bird)|rheas]], [[felidae|felines]] and other animals, as well as [[geometry|geometric]] shapes, [[zigzag]] patterns, representations of the sun, and [[hunting]] scenes. Similar paintings, though in smaller numbers, can be found in nearby caves. There are also red dots on the ceilings, probably made by submerging their hunting [[bolas]] in ink, and then throwing them up. The colours of the paintings vary from red (made from [[hematite]]) to white, black or yellow. The negative hand impressions date to around 550 BC, the positive impressions from 180 BC, while the hunting drawings are calculated to more than 10,000 years old.<ref name=comte_indigarg>{{cite book |last=Le Comte |first=Christian |title=Argentine Indians |year=2003 |publisher=Consorcio de Editores |isbn=987-9479-11-4 |url=https://archive.org/details/argentineindians00chri }}</ref>  Most of the hands are left hands,<ref name=":9">{{cite book|last1=Podest\u00e1|first1=Mar\u00eda Mercedes|url=https://www.google.co.uk/books/edition/El_arte_rupestre_de_Argentina_ind%C3%ADgena/NuG-pvgnd6IC?hl=en&gbpv=1&dq=%22Cueva+de+las+Manos%22+left+hand&pg=PA11&printsec=frontcover|title=El arte rupestre de Argentina ind\u00edgena: Patagonia|last2=Raffino|first2=Rodolfo A.|last3=Paunero|first3=Rafael Sebasti\u00e1n|last4=Rolandi|first4=Diana S.|publisher=Grupo Abierto Communicaciones|year=2005|isbn=978-987-1121-16-8|language=es|access-date=2021-03-01|archive-url=https://web.archive.org/web/20211029010950/https://www.google.co.uk/gen_204?s=web&t=aft&atyp=csi&ei=10l7Ye-DE4K60PEP6uey8A8&rt=wsrt.491,aft.4960,prt.2585&imn=26&ima=10&imad=9&aftp=18869&bl=TGeo|archive-date=2021-10-29|url-status=live}}</ref><ref>{{Cite book|last1=Steele|first1=James|title=Stone Knapping: the Necessary Conditions for a Uniquely Hominin Behaviour|last2=Uomini|first2=Natalie|date=2005|publisher=McDonald Institute for Archaeological Research, University of Cambridge|isbn=1-902937-34-1|editor-last=Roux|editor-first=Valentine|location=Cambridge, UK|page=234|chapter=Humans, tools and handedness|oclc=64118071|access-date=2021-04-23|editor-last2=Bril|editor-first2=Blandine|chapter-url=https://www.ucl.ac.uk/~tcrnjst/Steele%26Uomini2005.pdf|archive-url=https://web.archive.org/web/20211016025838/https://www.ucl.ac.uk/~tcrnjst/Steele%26Uomini2005.pdf|archive-date=2021-10-16|url-status=live}}</ref> which suggests that painters held the spraying pipe with their right hand.<ref name=":2">{{cite magazine|last=Parfit|first=Michael|date=December 2000|title=Hunt for the First Americans|magazine=[[National Geographic]]|publisher=[[National Geographic Society]]|volume=198|issue=6|page=40}}</ref><ref name=":23">{{Cite book|last=Wiesner-Hanks|first=Merry E.|title=A Concise History of the World|date=September 23, 2015|publisher=[[Cambridge University Press]]|isbn=978-1-107-02837-1|location=New York|pages=11\u201313|oclc=908262350|author-link=Merry Wiesner-Hanks}}</ref><ref>{{Cite book|last=Moore|first=Jerry D.|title=Incidence of travel: recent journeys in ancient South America|date=2017|publisher=[[University Press of Colorado]]|isbn=978-1-60732-600-7|location=Boulder|page=100|doi=10.5876/9781607326007|jstor=j.ctt1m3210q|lccn=2016053403|oclc=973325343}}</ref>\n\n There are rock paintings in caves in Thailand, Malaysia, Indonesia, and Burma. In [[Thailand]], caves and scarps along the Thai-Burmese border, in the Petchabun Range of Central Thailand, and overlooking the Mekong River in Nakorn Sawan Province, all contain galleries of rock paintings. In [[Malaysia]], the [[Tambun rock art]] is dated at 2000 years, and those in the Painted Cave at [[Niah Caves]] National Park are 1200 years old. The anthropologist [[Ivor Hugh Norman Evans]] visited Malaysia in the early 1920s and found that some of the tribes (especially Negritos) were still producing cave paintings and had added depictions of modern objects including what are believed to be automobiles.<ref>{{cite web |last=Weber |first=George |url=http://www.andaman.org/BOOK/chapter35/text35.htm |work=The Negrito of Malaysia |title=The Semang |access-date=11 May 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130724065848/http://andaman.org/BOOK/chapter35/text35.htm |archive-date=24 July 2013 }}</ref> (See [[prehistoric Malaysia]].)"}},
{"article_title": "Life extension", "pageid": "183290", "revid": "1059543174", "timestamp": "2021-12-10T02:18:35Z", "history_paths": [["Life extension --- Introduction ---", "History"]], "categories": ["life extension", "ageing", "emerging technologies", "population", "anti-aging substances", "transhumanism"], "heading_tree": {"Life extension --- Introduction ---": {"Average and maximum lifespan": {}, "Strategies": {"Diets and supplements": {"Dietary restriction": {}}, "Hormone treatment": {}}, "History": {"Scientific research": {}}, "Ethics and politics": {"Scientific controversy": {}, "Consumer motivations": {}, "Political parties": {}, "Silicon Valley": {}, "Commentators": {}, "Overpopulation concerns": {}, "Opinion polls": {}}, "Aging as a disease": {}, "Research": {"Anti-aging drugs": {}, "Nanotechnology": {}, "Cloning and body part replacement": {}, "Cyborgs": {}, "Cryonics": {}, "Strategies for engineered negligible senescence": {}, "Genetic editing": {}, "Fooling genes": {}, "Mind uploading": {}, "Young blood injection": {}, "Microbiome alterations": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Life extension --- Introduction ---|History": "{{Further|Timeline of senescence research}}\nThe extension of life has been a desire of humanity and a mainstay motif in the history of scientific pursuits and ideas throughout history, from the Sumerian [[Epic of Gilgamesh]] and the Egyptian [[Edwin Smith Papyrus|Smith medical papyrus]], all the way through the [[Taoists]], [[Ayurveda]] practitioners, [[alchemists]], [[hygienist]]s such as [[Luigi Cornaro]], Johann Cohausen and [[Christoph Wilhelm Hufeland]], and philosophers such as [[Francis Bacon]], [[Ren\u00e9 Descartes]], [[Benjamin Franklin]] and Nicolas [[Condorcet]]. However, the beginning of the modern period in this endeavor can be traced to the end of the 19th \u2013 beginning of the 20th century, to the so-called "[[fin-de-si\u00e8cle]]" (end of the century) period, denoted as an "end of an epoch" and characterized by the rise of scientific optimism and therapeutic activism, entailing the pursuit of life extension (or life-extensionism). Among the foremost researchers of life extension at this period were the Nobel Prize winning biologist [[Elie Metchnikoff]] (1845-1916) -- the author of the cell theory of immunity and vice director of Institut Pasteur in Paris, and [[Charles-\u00c9douard Brown-S\u00e9quard]] (1817-1894) -- the president of the French Biological Society and one of the founders of modern endocrinology.<ref>{{cite book|last1=Stambler|first1=Ilia|title=A History of Life-Extensionism in the Twentieth Century|date=2014|publisher=Longevity History|isbn=978-1500818579|url=http://www.longevityhistory.com/}}</ref>\n\nSociologist [[James Hughes (sociologist)|James Hughes]] claims that science has been tied to a cultural narrative of conquering death since the [[Age of Enlightenment]]. He cites [[Francis Bacon]] (1561\u20131626) as an advocate of using science and reason to extend human life, noting Bacon's novel ''[[New Atlantis]]'', wherein scientists worked toward delaying aging and prolonging life. [[Robert Boyle]] (1627\u20131691), founding member of the [[Royal Society]], also hoped that science would make substantial progress with life extension, according to Hughes, and proposed such experiments as "to replace the blood of the old with the blood of the young". Biologist [[Alexis Carrel]] (1873\u20131944) was inspired by a belief in indefinite human lifespan that he developed after experimenting with [[Cell (biology)|cells]], says Hughes.<ref name="HughesTranshumanism">{{cite book|last1=Hughes|first1=James|author-link=James Hughes (sociologist)|title=Leadership in Science and Technology: A Reference Handbook|date=October 20, 2011|publisher=[[Sage Publications]]|isbn=978-1452266527|page=587|chapter=Transhumanism|editor1-last=Bainbridge|editor1-first=William|editor1-link=William Sims Bainbridge}}</ref>\n\nRegulatory and legal struggles between the Food and Drug Administration (FDA) and the Life Extension organization included seizure of merchandise and court action.<ref>Andrew Zaleski, [https://www.popsci.com/forever-man-immortality-science/ Article in "Is there any truth to anti-aging schemes?"], ''Popular Science''June 12, 2018</ref> In 1991, Saul Kent and Bill Faloon, the principals of the organization, were jailed for four hours and were released on $850,000 bond each.<ref>Matt Schudel [https://www.sun-sentinel.com/news/fl-xpm-1992-12-06-9203040859-story.html/ "Is it a crime to live forever?"],''SunSentinel''December 6, 1992</ref> After 11 years of legal battles, Kent and Faloon convinced the US Attorney's Office to dismiss all criminal indictments brought against them by the FDA.<ref>[https://lifeboat.com/ex/bios.william.faloon "William Faloon"], ''lifeboatfoundation''</ref>\n\nIn 2003, [[Doubleday (publisher)|Doubleday]] published "The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging," by [[Michael D. West]]. West emphasised the potential role of embryonic stem cells in life extension.<ref>{{cite book|author=West, Michael D. |title=The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging|url=https://archive.org/details/imortalcell0000unse|url-access=registration |year=2003|publisher=Doubleday|isbn=978-0-385-50928-2}}</ref>\n\nOther modern life extensionists include writer [[Gennady Stolyarov II|Gennady Stolyarov]], who insists that death is "the enemy of us all, to be fought with medicine, science, and technology";<ref name="stolyarov">{{cite book|last1 = Stolyarov|first1 = Gennady|title = Death is Wrong|date = November 25, 2013|publisher = Rational Argumentator Press|isbn = 978-0615932040|url = http://rationalargumentator.com/Death_is_Wrong_Second_Edition_Full.pdf}}</ref> [[Transhumanism|transhumanist]] philosopher [[Zoltan Istvan]], who proposes that the "transhumanist must safeguard one's own existence above all else";<ref name="istvan">{{cite news |last1=Istvan|first1=Zoltan|url=http://www.huffingtonpost.com/zoltan-istvan/the-three-laws-of-transhu_b_5853596.html |title=The Morality of Artificial Intelligence and the Three Laws of Transhumanism |work=Huffington Post |date=October 2, 2014}}</ref> futurist [[George Dvorsky]], who considers aging to be a problem that desperately needs to be solved;<ref name=aja>{{cite web|title=Futurist: 'I will reap benefits of life extension'|url=http://america.aljazeera.com/watch/shows/fault-lines/articles/2015/5/7/futurist-itll-start-to-become-ridiculous-not-to-talk-about-curing-aging.html|website=Al Jazeera America|date=May 7, 2015|quote=To Dvorsky, aging is a problem that\u2019s desperately in need of solving.}}</ref> and recording artist [[Steve Aoki]], who has been called "one of the most prolific campaigners for life extension".<ref name=tez>{{cite web|last1=Tez|first1=Riva Melissa|title=Steve Aoki, Dan Bilzerian, a giraffe and the search for eternal life|url=https://i-d.vice.com/en_gb/article/steve-aoki-dan-bilzerian-a-giraffe-and-the-search-for-eternal-life|website=i-D|publisher=VICE|date=May 11, 2015|quote=Unknown to most, Steve is both an undeniable champion of life expansion as well as one of the most prolific campaigners for life extension. Understanding that the depth of his life's experience is limited by time alone, in his latest album Neon Future he pens lyrics such as 'Life has limitless variety... But today, because of ageing, it does not have limitless scope.' [...] Set up by the Steve Aoki Charitable Fund, the profits from the Dan Bilzerian party went to life extension research.}}</ref>\n\n \nIn 1991, the [[American Academy of Anti-Aging Medicine]] (A4M) was formed. The [[American Board of Medical Specialties]] recognizes neither anti-aging medicine nor the A4M's professional standing.<ref name="NYTPoison">{{Cite news |first=Alex |last= Kuczynski |date=12 April 1998 |title=Anti-Aging Potion Or Poison? |url=https://www.nytimes.com/1998/04/12/style/anti-aging-potion-or-poison.html |work=[[The New York Times]] |access-date=17 July 2009}}</ref>\n\nIn 2003, [[Aubrey de Grey]] and [[David Gobel]] formed the [[Methuselah Foundation]], which gives financial grants to anti-aging research projects. In 2009, de Grey and several others founded the [[SENS Research Foundation]], a California-based scientific research organization which conducts research into aging and funds other anti-aging research projects at various universities.<ref>[http://sens.org/files/pdf/2011_Research_Report.pdf research report 2011] {{Webarchive|url=https://web.archive.org/web/20120814133213/http://www.sens.org/files/pdf/2011_Research_Report.pdf |date=2012-08-14 }}. Sens Foundation</ref> In 2013, [[Google]] announced [[Calico (company)|Calico]], a new company based in San Francisco that will harness new technologies to increase scientific understanding of the biology of aging.<ref>{{cite web|url=http://www.cnn.com/2013/10/03/tech/innovation/google-calico-aging-death/|title=How Google's Calico aims to fight aging and 'solve death'|author=Arion McNicoll, Arion |date=3 October 2013|work=CNN}}</ref> It is led by [[Arthur D. Levinson]],<ref>{{cite web|url=http://googlepress.blogspot.com/2013/09/calico-announcement.html|title=Google announces Calico, a new company focused on health and well-being|date=September 18, 2013}}</ref> and its research team includes scientists such as [[Hal V. Barron]], [[David Botstein]], and [[Cynthia Kenyon]]. In 2014, biologist [[Craig Venter]] founded Human Longevity Inc., a company dedicated to scientific research to end aging through genomics and cell therapy. They received funding with the goal of compiling a comprehensive human genotype, microbiome, and phenotype database.<ref>{{cite web|url=http://www.prnewswire.com/news-releases/human-longevity-inc-hli-launched-to-promote-healthy-aging-using-advances-in-genomics-and-stem-cell-therapies-248379091.html|title=Human Longevity Inc. (HLI) Launched to Promote Healthy Aging Using Advances in... \u2013 SAN DIEGO, March 4, 2014 /PRNewswire/ --|author=Human Longevity Inc.|date=4 March 2014|access-date=12 August 2014|archive-url=https://web.archive.org/web/20141021000819/http://www.prnewswire.com/news-releases/human-longevity-inc-hli-launched-to-promote-healthy-aging-using-advances-in-genomics-and-stem-cell-therapies-248379091.html|archive-date=21 October 2014|url-status=dead}}</ref>\n\nAside from private initiatives, aging research is being conducted in university laboratories, and includes universities such as [[Harvard University|Harvard]] and [[University of California, Los Angeles|UCLA]]. University researchers have made a number of breakthroughs in extending the lives of mice and insects by reversing certain aspects of aging.<ref>{{cite web|url=http://www.cnn.com/2014/05/05/health/young-blood-mice-aging/|title=Young blood makes old mice more youthful|author=Landau, Elizabeth |date=5 May 2014|work=CNN}}</ref><ref>[http://www.gizmag.com/gdf11-protein-aging-mice-harvard/31929/ "Harvard researchers find protein that could reverse the aging process"]. ''gizmag.com''.</ref><ref>{{cite web|url=http://newsroom.ucla.edu/releases/ucla-biologists-delay-the-aging-process-by-remote-control|title=UCLA biologists delay the aging process by 'remote control'|author=Wolpert, Stuart |publisher=UCLA.edu}}</ref><ref>{{cite web|url=http://www.abc.net.au/news/2013-12-20/scientists-develop-anti-ageing-process-in-mice/5168580|title=Australian and US scientists reverse ageing in mice, humans could be next|work=ABC News|date=2013-12-19}}</ref>"}},
{"article_title": "Bicycle brake", "pageid": "183340", "revid": "1062020407", "timestamp": "2021-12-25T17:58:35Z", "history_paths": [["Bicycle brake --- Introduction ---", "History"]], "categories": ["bicycle parts", "vehicle braking technologies", "brakes", "bicycle brakes"], "heading_tree": {"Bicycle brake --- Introduction ---": {"History": {}, "Brake types": {"Spoon brakes": {}, "Duck brake": {}, "Rim brakes": {"Advantages and disadvantages": {}, "Brake pads": {}, "Types of rim brakes": {"Rod-actuated brakes": {}, "Caliper brakes": {}, "Side-pull caliper brakes": {}, "Centre-pull caliper brakes": {}, "U-brakes": {}, "Cantilever brakes": {}, "Traditional cantilever brakes": {}, "V-brakes": {}, "Roller cam brakes": {}, "Delta brakes": {}, "Hydraulic rim brakes": {}}}, "Disc brakes": {"Advantages": {}, "Disadvantages": {}, "Hydraulic vs. \"mechanical\"": {}, "Single vs. dual actuation": {}, "Multiple pistons": {}, "Caliper mounting standards": {}, "Advantages and disadvantages of various types of mounts": {}, "Disc mounting standards": {}, "Disc sizes": {}}, "Drum brakes": {}, "Coaster brakes": {}, "Drag brakes": {}, "Band brake": {}}, "Actuation mechanisms": {"Mechanical": {}, "Hydraulic": {"Hydraulic brake fluid": {}}, "Hybrid": {}, "Brake levers": {}}, "Braking technique": {}, "Bicycles without brakes": {}, "Single-lever two-wheel brakes": {}, "See also": {}, "References": {"Sources": {}}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Bicycle brake --- Introduction ---|History": "[[Karl Drais]] included a pivoting brake shoe that could be pressed against the rear iron tyre of his 1817 [[Laufmaschine]].<ref>{{cite book\n| title = Bicycle Design, An Illustrated History\n| author = Tony Hadland and Hans-Erhard Lessing\n| publisher = [[MIT Press]]\n| year = 2016\n| pages = 259\n| isbn = 978-0-262-02675-8}}</ref> This was continued on the earliest bicycles with pedals, such as the [[Boneshaker (bicycle)#Boneshaker|boneshaker]], which were fitted with a spoon brake to press onto the rear wheel.<ref name = "Clayton">{{cite book\n| pages = 8\u201315\n| author = Nick Clayton\n| title = Early Bicycles\n| year = 1986\n| publisher = Shire publications, Princes Risborough UK\n| isbn = 0-85263-803-5}}</ref> The brake was operated by a lever or by a cord connecting to the handlebars. The rider could also slow down by resisting the pedals of the fixed wheel drive.\n\nThe next development of the bicycle, the [[penny-farthing]]s, were similarly braked with a spoon brake or by back pedalling. During its development from 1870 to 1878, there were various designs for brakes, most of them operating on the rear wheel. However, as the rear wheel became smaller and smaller, with more of the rider's weight over the front wheel, braking on the rear wheel became less effective. The front brake, introduced by John Kean in 1873, had been generally adopted by 1880 because of its greater stopping power.<ref name = "Beeley">{{cite book\n| page = 32\n| title = A History of Bicycles\n| author = Serena Beeley\n| year = 1992\n| publisher = Studio Editions, London\n| isbn = 1-85170-753-0}}</ref>\n\nSome penny-farthing riders used only back pedalling and got off and walked down steep hills, but most also used a brake.<ref name = "Clayton"/> Having a brake meant that riders could coast down hill by taking their feet off the pedals and placing the legs over the handlebars, although most riders preferred to dismount and walk down steep hills.<ref name = "Beeley"/> Putting the legs under the handlebars with the feet off the pedals placed on foot-rests on the forks had resulted in serious accidents caused by the feet getting caught in the spokes.<ref name = "Clayton"/>\n\nAn alternative to the spoon brake for penny-farthings was the [[#The caliper brake design|caliper brake]] patented by Browett and Harrison in 1887.<ref>{{cite web\n| url = http://www.jimlangley.net/ride/bicyclehistorywh.html#tline\n| title = Myths and Milestones in Bicycle Evolution\n| last = Hudson\n| first = William\n| publisher = Jim Langley\n| year = 2008\n| access-date = 2009-09-22}}</ref>  This early version of caliper braking used a rubber block to contact the outside of the penny-farthing's small rear tyre.\n\nThe 1870s and 1880s saw the development of the [[safety bicycle]] which roughly resembles bicycles today, with two wheels of equal size, initially with solid rubber tyres. These were typically equipped with a front spoon brake and no rear brake mechanism, but like penny-farthings they used fixed gears, allowing rear wheel braking by resisting the motion of the pedals.  The relative fragility of the wooden rims used on most bicycles still precluded the use of rim brakes.{{Citation needed|date=July 2011}} In the late 1890s came the introduction of rim brakes and the freewheel.<ref name = "Clayton"/>\n\nWith the introduction of mass-produced [[Bicycle tire|pneumatic tyres]] by the [[Dunlop Rubber|Dunlop Tyre Company]], the use of spoon brakes began to decline, as they tended to quickly wear through the thin casing of the new tyres. This problem led to demands for alternative braking systems. On November 23, 1897, Abram W. Duck of Duck's Cyclery in Oakland, California was granted a patent for his ''Duck Roller Brake'' (U.S. Patent 594,234).<ref>Duck, Abram W., ''United States Patent Office, Letters Patent No. 594,234'', November 23, 1897</ref> The [[#Duck Brake|duck brake]] used a rod operated by a lever on the handlebar to pull twin rubber rollers against the front tyre, braking the front wheel.<ref name="ReferenceA">Duck, Abram W., ''Patent No. 594,234''</ref>\n\nIn 1898, after the advent of [[freewheel]] coasting mechanisms, the first internal [[coaster brake]]s were introduced for the rear wheel.  The coaster brake was contained in the rear wheel hub, and was engaged and controlled by backpedaling, thus eliminating the issue of tyre wear.  In the United States, the coaster brake was the most commonly fitted brake throughout the first half of the 20th century, often comprising the only braking system on the bicycle."}},
{"article_title": "Cucoloris", "pageid": "183554", "revid": "1036285708", "timestamp": "2021-07-30T15:53:28Z", "history_paths": [["Cucoloris --- Introduction ---", "History"]], "categories": ["film production", "stage lighting", "film and video technology"], "heading_tree": {"Cucoloris --- Introduction ---": {"Etymology": {}, "Overview": {}, "History": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Cucoloris --- Introduction ---|History": "Cinematographer [[George J. Folsey]], [[American Society of Cinematographers|ASC]] thus recounted the history: \n<blockquote>While shooting a scene with an actor who was wearing a white shirt, he wanted to separate the skin tones on the actor\u2019s face from the hue of the shirt. Folsey told a grip to hold a stepladder in front of a key light to create a shadow on the actor\u2019s shirt. The closer that the ladder was held to the light, the softer and less defined the shadow became. The grip eventually tired of holding the ladder, so he cut a grill with the same pattern in a sheet of light wood. One day, Folsey visited [[Hal Rosson]], ASC, who was shooting on another set. In the scene, an actress was lying on a bed swathed in white sheets. Rosson used Folsey\u2019s wooden grill to create some shadows, which made the scene more dramatic. Later, while shooting a similar situation, Rosson asked Folsey, \u201cWhere\u2019s that kookaloris thing?\u201d <ref>[http://motion.kodak.com/motion/Education/Publications/Essential_reference_guide/index.htm?CID=go&idhbx=referenceguide Kodak: The Essential Reference Guide for Filmmakers]</ref></blockquote>"}},
{"article_title": "Microbotics", "pageid": "184570", "revid": "1057221959", "timestamp": "2021-11-26T07:00:21Z", "history_paths": [["Microbotics --- Introduction ---", "History"]], "categories": ["robotics", "microtechnology", "micro robots"], "heading_tree": {"Microbotics --- Introduction ---": {"History": {}, "Design considerations": {}, "See also": {}, "References": {}}}, "more_than_two_sections_excluding_boilerplate": false, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Microbotics --- Introduction ---|History": "Microbots were born thanks to the appearance of the [[microcontroller]] in the last decade of the 20th century, and the appearance of miniature mechanical systems on silicon (MEMS), although many microbots do not use silicon for mechanical components other than sensors. {{Anchor|national2016-01-29}}The earliest research and conceptual design of such small robots was conducted in the early 1970s in (then) [[Classified information|classified]] research for U.S. [[intelligence agencies]]. Applications envisioned at that time included [[prisoner of war]] rescue assistance and electronic intercept missions. The underlying miniaturization support technologies were not fully developed at that time, so that progress in [[prototype]] development was not immediately forthcoming from this early set of calculations and concept design.<ref>{{cite journal|last=Solem|first=J. C.|year=1996|title=The application of microrobotics in warfare|journal=Los Alamos National Laboratory Technical Report LAUR-96-3067|doi=10.2172/369704|url=http://www.osti.gov/scitech/servlets/purl/369704}}</ref> As of 2008, the smallest microrobots use a [[Scratch Drive Actuator]].<ref>{{cite news|url=http://news.duke.edu/2008/06/microrobots.html|title=Microrobotic Ballet|publisher=[[Duke University]]|date=June 2, 2008|access-date=2014-08-24|archive-url=https://web.archive.org/web/20110403132202/http://news.duke.edu/2008/06/microrobots.html|archive-date=2011-04-03|url-status=dead}}</ref>\n\nThe development of [[wireless]] connections, especially [[Wi-Fi]] (i.e. in [[Home automation|household networks]]) has greatly increased the communication capacity of microbots, and consequently their ability to coordinate with other microbots to carry out more complex tasks. Indeed, much recent research has focused on microbot communication, including a 1,024 robot swarm at [[Harvard University]] that assembles itself into various shapes;<ref>{{cite news|url=https://arstechnica.com/science/2014/08/thousand-robot-swarm-assembles-itself-into-shapes/|title=Thousand-robot swarm assembles itself into shapes|first=Sabine|last=Hauert|work=[[Ars Technica]]|date=2014-08-14|access-date=2014-08-24}}</ref> and manufacturing microbots at [[SRI International]] for DARPA's "MicroFactory for Macro Products" program that can build lightweight, high-strength structures.<ref>{{cite news|url=http://io9.com/this-swarm-of-insect-inspired-microbots-is-unsettlingly-1566115702|title=This Swarm Of Insect-Inspired Microbots Is Unsettlingly Clever|work=[[io9]]|first=Ria|last=Misra|date=2014-04-22|access-date=2014-08-24}}</ref><ref>{{cite news|url=http://recode.net/2014/04/16/sri-unveils-tiny-robots-ready-to-build-big-things/|title=SRI Unveils Tiny Robots Ready to Build Big Things|first=James|last=Temple|work=[[re/code]]|date=2014-04-16|access-date=2014-08-24}}</ref>\n\nMicrobots called [[xenobot|xenobots]] have also been built using biological tissues instead of metal and electronics.<ref name="xenobots">{{cite journal |last1=Kriegman |first1=Sam |last2=Blackiston |first2=Douglas |last3=Levin |first3=Michael |last4=Bongard |first4=Josh |title=A scalable pipeline for designing reconfigurable organisms |journal=Proceedings of the National Academy of Sciences |date=2020 |volume=117 |issue=4 |pages=1853\u20131859|doi=10.1073/pnas.1910837117|pmid=31932426 |pmc=6994979 }}</ref> Xenobots avoid some of the technological and environmental complications of traditional microbots as they are self-powered, biodegradable, and biocompatible."}},
{"article_title": "PIC microcontrollers", "pageid": "184588", "revid": "1062277640", "timestamp": "2021-12-27T13:18:01Z", "history_paths": [["PIC microcontrollers --- Introduction ---", "History"]], "categories": ["microcontrollers", "instruction set architectures", "microchip technology hardware"], "heading_tree": {"PIC microcontrollers --- Introduction ---": {"History": {"Original concept": {}, "After the 1600": {}}, "Device families": {"PIC10 and PIC12": {}, "PIC16": {}, "PIC17": {}, "PIC18": {}, "PIC24 and dsPIC": {}, "PIC32M MIPS-based line": {"PIC32MX": {}, "PIC32MZ": {}, "PIC32MM": {}, "PIC32MK": {}}}, "Core architecture": {"Data space (RAM)": {}, "Code space": {}, "Word size": {}, "Stacks": {}, "Instruction set": {}, "Performance": {}, "Advantages": {}, "Limitations": {}, "Compiler development": {}}, "Hardware features": {"Variants": {}, "Trends": {}, "Part number": {}}, "Development tools": {}, "Device programmers": {"Bootloading": {}, "Third party": {}}, "Debugging": {"In-circuit debugging": {}, "In-circuit emulators": {}}, "Operating systems": {}, "Clones": {"Parallax": {}, "PKK Milandr": {}, "ELAN Microelectronics": {}, "Holtek Semiconductor": {}, "Other manufacturers in Asia": {}}, "See also": {}, "References": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"PIC microcontrollers --- Introduction ---|History": "[[Image:PIC16CxxxWIN.JPG|thumb|Various older (EPROM) PIC microcontrollers]]\nThe original PIC was intended to be used with General Instrument's new [[General Instrument CP1600|CP1600]] [[16-bit]] [[central processing unit]] (CPU). In order to fit 16-bit [[Bus (computing)|data bus]] and [[address bus]] into a then-standard 40-pin [[dual inline package]] (DIP) chip, the two busses shared the same set of 16 connection pins. In order to communicate with the CPU, devices had to watch other pins on the CPU to determine if the data on the bus was an address or data. Since only one of these was being presented at a time, the devices had to watch the bus to go into address mode, see if that address was part of its [[Memory-mapped I/O|memory mapped input/output]] range, "latch" that address and then wait for the data mode to turn on and then read the value. Additionally, the 1600 used several external pins to select which device it was attempting to talk to, further complicating the interfacing.\n\nAs interfacing devices to the 1600 could be complex, GI also released a series of support chips with all of the required circuitry built-in. These included keyboard drivers, [[cassette deck]] interfaces for storage, and a host of similar systems. For more complex systems, GI introduced the 8-bit PIC in 1975. The idea was that a device would use the PIC to handle all the interfacing with the host computer's CP1600, but also use its own internal processor to handle the actual device it was connected to. For instance, a [[floppy disk drive]] could be implemented with a PIC talking to the CPU on one side and the [[floppy disk controller]] on the other. In keeping with this idea, what would today be known as a [[microcontroller]], the PIC included a small amount of [[read-only memory]] (ROM) that would be written with the user's device controller code, and a separate [[random access memory]] (RAM) for buffering and working with data. These were connected separately, making the PIC a [[Harvard architecture]] system with code and data being managed on separate internal pathways.\n\nIn theory, the combination of 1600 CPU and PIC device controllers provided a very high-performance device control system, one that was similar in power and performance to the [[channel controller]]s see on [[mainframe computer]]s. In the floppy controller example, for instance, a single PIC could control the drive, provide a reasonable amount of buffering to improve performance, and then transfer data to and from the host computer using [[direct memory access]] (DMA) or through relatively simple code in the CPU. The downside to this approach was cost; while the PIC was not necessary for low-speed devices like a keyboard, many tasks would require one or more PICs to build out a complete system.\n\nWhile the design concept had a number of attractive features, General Instrument never strongly marketed the 1600, preferring to deal only with large customers and ignoring the low-end market. This resulted in very little uptake of the system, with the [[Intellivision]] being the only really widespread use with about three million units. When GI spun off its chip division to form [[Microchip Technology]] in 1985, production of the CP1600 ended. By this time, however, the PIC had developed a large market of customers using it for a wide variety of roles, and the PIC went on to become one of the new company's primary products.\n\n In 1985, General Instrument sold their [[microelectronics]] division and the new owners cancelled almost everything which by this time was mostly out-of-date. The PIC, however, was upgraded with an internal [[EPROM]] to produce a programmable [[Channel I/O|channel controller]].\nAt the same time [[Plessey]] in the UK released NMOS processors numbered PIC1650 and PIC1655 based on the GI design, using the same instruction sets, either user mask programmable or versions pre-programed for auto-diallers and keyboard interfaces. <ref>Plessey Satellite Cable TV Integrated Circuit Handbook May 1986</ref> \n\nIn 1998 Microchip introduced the PIC 16F84, a flash programmable and erasable version of its successful serial programmable PIC16C84. \nIn 2001, Microchip introduced more Flash programmable devices, with full production commencing in 2002. [http://www.eetimes.com/document.asp?doc_id=1130372]\n\nToday, a huge variety of PICs are available with various on-board peripherals ([[serial communication]] modules, [[universal asynchronous receiver/transmitter|UART]]s, motor control kernels, etc.) and program memory from 256 words to 64K words and more (a "word" is one assembly language instruction, varying in length from 8 to 16 [[bit]]s, depending on the specific PIC [[Micro programming language|micro]] family).\n\nPIC and PICmicro are now registered trademarks of Microchip Technology. It is generally thought that PIC stands for '''Peripheral Interface Controller''', although General Instruments' original acronym for the initial PIC1640 and PIC1650 devices was "'''Programmable Interface Controller'''".<ref name="1976databook"/>  The acronym was quickly replaced with "'''Programmable Intelligent Computer'''".<ref name="1977catalog"/>\n\nThe Microchip 16C84 ([[PIC16x84]]), introduced in 1993, was the first<ref>{{cite web\n |url=https://spectrum.ieee.org/tech-history/silicon-revolution/chip-hall-of-fame-microchip-technology-pic-16c84-microcontroller\n |title=Chip Hall of Fame: Microchip Technology PIC 16C84 Microcontroller\n |date=30 June 2017\n |publisher=IEEE\n |access-date=September 16, 2018}}</ref> Microchip CPU with on-chip EEPROM memory.         \n\nBy 2013, Microchip was shipping over one billion PIC microcontrollers every year. <ref>{{cite web\n |url=http://www.microchip.com/pagehandler/en-us/press-release/microchips-12-billionth-pic-mi.html\n |title=Microchip Technology Delivers 12 Billionth PIC\u00ae Microcontroller to Leading Motor Manufacturer, Nidec Corporation\n |last=Lawson\n |first=Eric\n |date=May 16, 2013\n |publisher=Microchip press release.\n |access-date=December 21, 2017\n |archive-url=https://web.archive.org/web/20130721063936/https://www.microchip.com/pagehandler/en-us/press-release/microchips-12-billionth-pic-mi.html\n |archive-date=July 21, 2013\n |quote="Microchip delivered this 12 billionth MCU approximately 10 months after delivering its 11 billionth."}}\n</ref>"}},
{"article_title": "Stirling engine", "pageid": "186919", "revid": "1061164490", "timestamp": "2021-12-20T01:36:56Z", "history_paths": [["Stirling engine --- Introduction ---", "History"]], "categories": ["cooling technology", "heat pumps", "stirling engines", "hot air engines", "piston engines", "scottish inventions", "articles containing video clips", "external combustion engines"], "heading_tree": {"Stirling engine --- Introduction ---": {"History": {"Early hot air engines": {}, "Invention and early development": {}, "Later 19th century": {}, "20th century revival": {}}, "21st century developments": {}, "Name and classification": {}, "Theory": {}, "Components": {"Heat source": {}, "Heat exchangers": {}, "Regenerator": {}, "Heat sink": {}, "Displacer": {}}, "Configurations": {"Alpha": {}, "Beta": {}, "Gamma": {}}, "Other types": {"Free-piston engines": {}, "Flat engines": {}, "Thermoacoustic cycle": {}, "Other developments": {}}, "Operational considerations": {"Size and temperature": {}, "Gas choice": {}, "Pressurization": {}, "Lubricants and friction": {}}, "Efficiency": {}, "Comparison with internal combustion engines": {}, "Applications": {}, "See also": {}, "References": {}, "Bibliography": {}, "Further reading": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": true, "history_section_designated_fuzzy": false, "history_section_non_designated": false, "history_section_texts": {"Stirling engine --- Introduction ---|History": "{{rewrite|section|date=June 2021}}\n[[File:Robert Stirling's engine patent.gif|thumb|Illustration from Robert Stirling's 1816 patent application of the air engine design that later came to be known as the Stirling Engine]]\n\n \n[[Robert Stirling]] is considered one of the fathers of hot air engines, notwithstanding some earlier predecessors\u2014notably [[Guillaume Amontons]]<ref name="haeamontons-s01" />\u2014who succeeded in building, in 1699, the first working hot air engine.{{citation needed|date=July 2020}}\n\nAmontons was later followed by Sir [[George Cayley]].<ref name="haecayley1807-s01" /> This engine type was of those in which the fire is enclosed, and fed by air pumped in beneath the grate in sufficient quantity to maintain combustion, while by far the largest portion of the air enters above the fire, to be heated and expanded; the whole, together with the products of combustion, then acts on the piston, and passes through the working cylinder; and the operation being one of simple mixture only, no heating surface of metal is required, the air to be heated being brought into immediate contact with the fire.{{citation needed|date=July 2020}}\n\nStirling came up with a first air engine in 1816.<ref name="haestirling1816-s01" /> The principle of the Stirling Air Engine differs from that of Sir [[George Cayley]] (1807), in which the air is forced through the furnace and exhausted, whereas in Stirling's engine the air works in a closed circuit. It was to it that the inventor devoted most of his attention.{{citation needed|date=July 2020}}\n\nA {{convert|2|hp|adj=on}} engine, built in 1818 for pumping water at an Ayrshire quarry, continued to work for some time, until a careless attendant allowed the heater to become overheated. This experiment proved to the inventor that, owing to the low working pressure obtainable, the engine could only be adapted to small powers for which there was, at that time, no demand.{{citation needed|date=July 2020}}\n\nThe Stirling 1816 patent<ref name="haestirling1816-s02" /> was also about an "[[Economizer|Economiser]]", which is the predecessor of the regenerator. In this patent (# 4081) he describes the "economiser" technology and several applications where such technology can be used. Out of them came a new arrangement for a hot air engine.{{citation needed|date=July 2020}}\n\nStirling patented a second hot air engine, together with his brother James, in 1827.<ref name="haestirling1827-s01" /> They inverted the design so that the hot ends of the displacers were underneath the machinery and they added a compressed air pump so the air within could be increased in pressure to around {{convert|20|atm}}.{{citation needed|date=July 2020}}\n\nThe two Stirling brothers were followed shortly after (1828) by Parkinson & Crossley<ref name="haeparkinson&crossley" /> and Arnott<ref name="haearnott-s01" /> in 1829.{{citation needed|date=July 2020}}\n\nThese precursors, to whom Ericsson<ref name="haeericsson" /> should be added, have brought to the world the hot air engine technology and its enormous advantages over the steam engine. Each of them came with his own specific technology, and although the Stirling engine and the Parkinson & Crossley engines were quite similar, Robert Stirling distinguished himself by inventing the regenerator.{{citation needed|date=July 2020}}\n\nParkinson and Crosley introduced the principle of using air of greater density than that of the atmosphere, and so obtained an engine of greater power in the same compass. James Stirling followed this same idea when he built the famous Dundee engine.<ref name="haestirling1842" />\n\nThe Stirling patent of 1827 was the base of the Stirling third patent of 1840.<ref name="haestirling1842patent-2" /> The changes from the 1827 patent were minor but essential, and this third patent led to the Dundee engine.<ref name="haestirling1842-2" />\n\nJames Stirling presented his engine to the Institution of Civil Engineers in 1845.<ref name="haestirling1842-S03" /> The first engine of this kind which, after various modifications, was efficiently constructed and heated, had a cylinder of {{convert|12|inch|cm|order=flip|abbr=off}} in diameter, with a length of stroke of {{convert|2|ft|cm|order=flip|round=5}}, and made 40 strokes or revolutions in a minute (40 rpm). This engine moved all the machinery at the Dundee Foundry Company's works for eight or ten months, and was previously found capable of raising 320,000 kg (700,000 lbs) 60 cm (2 ft) in a minute, a power of approximately {{convert|21|hp|kW|order=flip|abbr=off}}.{{citation needed|date=July 2020}}\n\nFinding this power insufficient for their works, the Dundee Foundry Company erected the second engine, with a cylinder of {{convert|16|inch|cm|order=flip|abbr=off|round=5}} in diameter, a stroke of {{convert|4|ft|m|order=flip|abbr=off}}, and making 28 strokes in a minute. When this engine had been in continual operation for upwards of two years, it had not only performed the work of the foundry in the most satisfactory manner, but had been tested (by a friction brake on a third mover) to the extent of lifting nearly {{convert|687|t|lb|lk=on|abbr=off|sigfig=2}}, a power of approximately {{convert|45|hp|kW|order=flip|abbr=off}}.{{citation needed|date=July 2020}}\n\nThis gives a consumption of {{convert|2.7|lb|kg|abbr=off|order=flip}} per horse-power per hour; but when the engine was not fully burdened, the consumption was considerably under {{convert|2.5|lb|kg|abbr=off|order=flip}} per horse-power per hour. This performance was at the level of the best steam engines whose efficiency was about 10%. After James Stirling, such efficiency was possible only thanks to the use of the economiser (or regenerator).{{citation needed|date=July 2020}}\n\n \nThe Stirling engine (or Stirling's air engine as it was known at the time) was invented and patented in 1816.<ref name="Sier-1999" /> It followed [[Hot air engine#History|earlier attempts at making an air engine]] but was probably the first put to practical use when, in 1818, an engine built by Stirling was employed pumping water in a [[quarry]].<ref name="Finkelstein-2001-2.2" /> The main subject of Stirling's original patent was a heat exchanger, which he called an "[[economiser]]" for its enhancement of fuel economy in a variety of applications. The patent also described in detail the employment of one form of the economiser in his unique closed-cycle [[hot air engine|air engine]] design<ref name="patent-1816" /> in which application it is now generally known as a "[[#Regenerator|regenerator]]". Subsequent development by Robert Stirling and his brother [[James Stirling (1800\u20131876)|James]], an engineer, resulted in patents for various improved configurations of the original engine including pressurization, which by 1843, had sufficiently increased power output to drive all the machinery at a [[Dundee]] iron foundry.<ref name="Sier-1995-93" />\n\nA paper presented by James Stirling in June 1845 to the [[Institution of Civil Engineers]] stated that his aims were not only to save fuel but also to create a safer alternative to the [[steam engine]]s of the time,<ref name="Sier-1995-92" /> whose [[boiler]]s frequently exploded, causing many injuries and fatalities.<ref name="Nesmith-1985" /><ref name="Chuse-1992-1" /> This has however been disputed.<ref name="Organ-2008a" />\n\nThe need for Stirling engines to run at very high temperatures to maximize power and efficiency exposed limitations in the materials of the day, and the few engines that were built in those early years suffered unacceptably frequent failures (albeit with far less disastrous consequences than boiler explosions).<ref name="Sier-1995-94" /> For example, the Dundee foundry engine was replaced by a steam engine after three hot cylinder failures in four years.<ref name="Finkelstein-2001-30" />\n\n [[File:Ericsson hot air engine.jpg|thumb|upright|left|A typical late nineteenth/early twentieth century water pumping engine by the [[Rider-Ericsson Engine Company]]]]\n\nSubsequent to the replacement of the Dundee foundry engine there is no record of the Stirling brothers having any further involvement with air engine development, and the Stirling engine never again competed with steam as an industrial scale power source. (Steam boilers were becoming safer, e.g. the Hartford Steam Boiler<ref name="Hartford" /> and steam engines more efficient, thus presenting less of a target for rival prime movers). However, beginning about 1860, smaller engines of the Stirling/hot air type were produced in substantial numbers for applications in which reliable sources of low to medium power were required, such as pumping air for church organs or raising water.<ref name="Finkelstein-2001-2.4" /> These smaller engines generally operated at lower temperatures so as not to tax available materials, and so were relatively inefficient. Their selling point was that unlike steam engines, they could be operated safely by anybody capable of managing a fire. The 1906 Rider-Ericsson Engine Co. catalog claimed that "any gardener or ordinary domestic can operate these engines and no licensed or experienced engineer is required".{{cn|date=May 2021}} Several types remained in production beyond the end of the century, but apart from a few minor mechanical improvements the design of the Stirling engine in general stagnated during this period.<ref name="Finkelstein-2001-64" />\n\n [[File:Philips Stirling engine.JPG|thumb|Philips MP1002CA Stirling generator of 1951]]\n\nDuring the early part of the 20th century, the role of the Stirling engine as a "domestic motor"<ref name="Finkelstein-2001-34" /> was gradually taken over by [[electric motor]]s and small [[internal combustion engine]]s. By the late 1930s, it was largely forgotten, only produced for toys and a few small ventilating fans.<ref name="Finkelstein-2001-55" />\n\nAround that time, [[Philips]] was seeking to expand sales of its radios into parts of the world where grid electricity and batteries were not consistently available. Philips' management decided that offering a low-power portable generator would facilitate such sales and asked a group of engineers at the company's research lab in [[Eindhoven]] to evaluate alternative ways of achieving this aim. After a systematic comparison of various [[prime mover (locomotive)|prime movers]], the team decided to go forward with the Stirling engine, citing its quiet operation (both audibly and in terms of radio interference) and ability to run on a variety of heat sources (common lamp oil \u2013 "cheap and available everywhere" \u2013 was favored).<ref name="Hargreaves-1991-28-30" /> They were also aware that, unlike steam and internal combustion engines, virtually no serious development work had been carried out on the Stirling engine for many years and asserted that modern materials and know-how should enable great improvements.<ref name="Philips-1947" />\n\nBy 1951, the 180/200 W generator set designated MP1002CA (known as the "Bungalow set") was ready for production and an initial batch of 250 was planned, but soon it became clear that they could not be made at a competitive price. Additionally, the advent of transistor radios and their much lower power requirements meant that the original rationale for the set was disappearing. Approximately 150 of these sets were eventually produced.<ref name="Hargreaves-1991-61" /> Some found their way into university and college engineering departments around the world, giving generations of students a valuable introduction to the Stirling engine; a letter dated March 1961 from Research and Control Instruments Ltd. London WC1 to North Devon Technical College, offering "remaining stocks... to institutions such as yourselves... at a special price of \u00a375 nett".{{citation needed|date=July 2020}}\n\nIn parallel with the Bungalow set, Philips developed experimental Stirling engines for a wide variety of applications and continued to work in the field until the late 1970s, but only achieved commercial success with the "reversed Stirling engine" [[Applications of the Stirling engine#Stirling cryocoolers|cryocooler]]. However, they filed a large number of patents and amassed a wealth of information, which they licensed to other companies and which formed the basis of much of the development work in the modern era.<ref name="Hargreaves-1991-77" />\n\nIn 1996, the Swedish navy commissioned three [[Gotland-class submarine]]s. On the surface, these boats are propelled by marine diesel engines. However, when submerged, they use a Stirling-driven generator developed by Swedish shipbuilder [[Kockums]] to recharge batteries and provide electrical power for propulsion.<ref name="Kockums" /> A supply of liquid oxygen is carried to support burning of diesel fuel to power the engine. Stirling engines are also fitted to the Swedish [[S\u00f6dermanland-class submarine]]s, the [[Archer-class submarine]]s in service in Singapore and, license-built by [[Kawasaki Heavy Industries]] for the Japanese [[S\u014dry\u016b-class submarine]]s. In a submarine application, the Stirling engine offers the advantage of being exceptionally quiet when running.{{citation needed|date=July 2020}}"}},
{"article_title": "Sound Blaster", "pageid": "187711", "revid": "1061432344", "timestamp": "2021-12-21T17:51:52Z", "history_paths": [["Sound Blaster --- Introduction ---", "Creative Music System and Game Blaster"], ["Sound Blaster --- Introduction ---", "First generation Sound Blasters, 8-bit ISA & MCA cards"], ["Sound Blaster --- Introduction ---", "Second-generation Sound Blasters, 16-bit ISA & MCA cards"], ["Sound Blaster --- Introduction ---", "Third generation Sound Blasters, 16-bit ISA cards"], ["Sound Blaster --- Introduction ---", "Fourth generation Sound Blasters, 16-bit ISA cards, dynamic sample-based synthesis"], ["Sound Blaster --- Introduction ---", "Fifth generation Sound Blasters, PCI cards, multi-channel and F/X"], ["Sound Blaster --- Introduction ---", "Sixth generation Sound Blaster ''Sound Core3D'' cards"], ["Sound Blaster --- Introduction ---", "Sound BlasterX Series"]], "categories": ["products introduced in 1987", "ibm pc compatibles", "creative technology products", "sound cards", "singaporean brands"], "heading_tree": {"Sound Blaster --- Introduction ---": {"Creative Music System and Game Blaster": {"Creative Music System": {}, "Game Blaster": {}}, "First generation Sound Blasters, 8-bit ISA & MCA cards": {"Sound Blaster 1.0, CT1310, CT1320A, CT1320B": {"Reception": {}}, "Sound Blaster 1.5, CT1320C, CT1320U": {}, "Sound Blaster 2.0, CT1350": {}, "Sound Blaster MCV, CT5320": {}}, "Second-generation Sound Blasters, 16-bit ISA & MCA cards": {"Sound Blaster Pro, CT1330": {}, "Sound Blaster Pro 2, CT1600": {}, "Sound Blaster Pro 2 MCV, CT5330": {}}, "Third generation Sound Blasters, 16-bit ISA cards": {"Sound Blaster 16": {}, "Sound Blaster ViBRA16": {}}, "Fourth generation Sound Blasters, 16-bit ISA cards, dynamic sample-based synthesis": {"Sound Blaster AWE32": {}, "Sound Blaster 32": {}, "Sound Blaster AWE64": {}}, "Fifth generation Sound Blasters, PCI cards, multi-channel and F/X": {"Ensoniq AudioPCI-based cards": {}, "Sound Blaster Live!": {}, "Sound Blaster PCI 512": {}, "Sound Blaster Audigy": {}, "Sound Blaster X-Fi": {}}, "Sixth generation Sound Blaster ''Sound Core3D'' cards": {"Sound Blaster Recon3D": {}, "Sound Blaster Z-Series": {}, "Sound BlasterX AE-5/Plus": {}, "Sound Blaster AE-7": {}, "Sound Blaster AE-9": {}}, "USB audio devices": {}, "Sound BlasterX Series": {"BlasterX Acoustic Engine": {"BlasterX Acoustic Engine Lite": {}, "BlasterX Acoustic Engine Pro": {}}, "Sound BlasterX gaming headsets": {}, "Sound BlasterX USB audio devices": {"Sound BlasterX G5": {}, "Sound BlasterX G1": {}}}, "Connectors": {"External connector": {}, "Internal pin connector and jumper": {}}, "Driver software modification (soft mod)": {}, "Audio effects processor": {}, "Compatibility with Linux": {}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Sound Blaster --- Introduction ---|Creative Music System and Game Blaster": "[[Image:Creative_Music_System.jpg|thumb|Creative Music System sound card]]\nThe history of Creative [[sound card]]s started with the release of the Creative Music System ("C/MS") CT-1300 board in August 1987. It contained two [[Philips SAA1099]] integrated circuits, which, together, provided 12 channels of [[Square wave|square-wave]] "bee-in-a-box" stereo sound, 4 channels of which can be used for noise.\n\nThese ICs were featured earlier in various popular electronics magazines around the world. For many years Creative tended to use off-the-shelf components and manufacturers' reference designs for their early products. The various integrated circuits had white or black paper stickers fully covering their top thus hiding their identity. On the C/MS board in particular, the Philips chips had white pieces of paper with a fantasy CMS-301 inscription on them: real Creative parts usually had consistent '''CT ''number''''' references.\n\nSurprisingly, the board also contained a large 40-pin DIP integrated circuit, bearing a CT 1302A CTPL 8708 (Creative Technology Programmable Logic) [[Screen-printing|serigraphed]] inscription and looking exactly like the DSP of the later Sound Blaster. This chip allows software to automatically detect the card by certain register reads and writes.\n\n A year later, in 1988, Creative marketed the C/MS via [[Radio Shack]] under the name Game Blaster. This card was identical in every way to the precursor C/MS hardware. Whereas the C/MS package came with five floppy disks full of utilities and song files, Creative supplied only a single floppy with the basic utilities and game patches to allow [[Sierra Online]]'s games using the [[Sierra Creative Interpreter]] engine to play music with the card and it also included a later revision of the game [[Silpheed]] that added C/MS support.\n\nIn 2017 hobbyists developed a clone CT1300 PCB.<ref>{{Cite web|url=http://www.vcfed.org/forum/showthread.php?59846-Creative-Music-System-Game-Blaster-clone&p=478654#post478654|title=Creative Music System / Game Blaster clone}}</ref>", "Sound Blaster --- Introduction ---|First generation Sound Blasters, 8-bit ISA & MCA cards": "[[Image:Soundblaster-1.0-ct1320.jpg|thumb|Sound Blaster 1.0 (CT1320B); C/MS chips in sockets (labeled U14, U15) are seen.]]\n\nThe Sound Blaster 1.0 (code named "'''Killer Kard'''"),<ref name="scisco198910">{{cite news | url=https://archive.org/stream/1989-10-compute-magazine/Compute_Issue_113_1989_Oct#page/n11/mode/2up | title=Sound-board Duet | work=Compute! | date=October 1989 | access-date=11 November 2013 | author=Scisco, Peter | page=10}}</ref> CT1320A, was released in 1989. In addition to Game Blaster features, it had an 11-voice [[Frequency modulation synthesis|FM synthesizer]] using the [[Yamaha YM3812]] chip, also known as [[OPL2]]. It provided perfect compatibility with the market leader [[AdLib]] sound card, which had gained support in PC games in the preceding year. Creative used the "DSP" acronym to designate the digital audio part of the Sound Blaster. This actually stood for Digital Sound Processor, rather than the more common [[digital signal processor]], and was really a simple micro-controller from the [[Intel]] [[Intel 8051|MCS-51]] family (supplied by Intel and [[Matra|Matra MHS]], among others). It could play back 8-bit [[monaural]] [[sampling (signal processing)|sampled sound]] at up to 23 [[kHz]] [[sampling frequency]] and record 8-bit at up to 12 kHz. The sole DSP-like features of the circuit were [[ADPCM]] decompression and a primitive non-MPU-401 compatible MIDI interface.  The ADPCM decompression schemes supported were 2 to 1, 3 to 1 and 4 to 1.  The CT1320B variety of the Sound Blaster 1.0 typically has C/MS chips installed in sockets rather than soldered on the PCB, though units do exist with the C/MS chips soldered on.<ref>[http://www.cgi.com/261329619999 ]{{dead link|date=July 2016}}</ref>\n\nSome sources note that the original Sound Blaster 1.0 was produced under the CT1310 number. This however is a topic of ongoing debate. Creative refers to CT1310 for the Sound Blaster 1.0 on its website.<ref>[https://archive.today/20131114154346/http://queststudios.com/smf/index.php?PHPSESSID=71b7440be27e8887a9b4c0b717ca54ba&topic=2590.20 ]</ref><ref>{{cite web|url=http://www.vintage-computer.com/vcforum/showthread.php?23903-CT1310-model-number-for-the-Soundblaster-1-0-a-myth|archive-url=https://web.archive.org/web/20131224115958/http://www.vintage-computer.com/vcforum/showthread.php?23903-CT1310-model-number-for-the-Soundblaster-1-0-a-myth|url-status=dead|archive-date=24 December 2013|title=CT1310 model number for the Soundblaster 1.0 - a myth?|website=Vintage-computer.com|access-date=12 July 2016}}</ref><ref>{{cite web|url=http://support.creative.com/kb/ShowArticle.aspx?url=http://ask.creative.com:80/srvs/cgi-bin/webcgi.exe/,/?st=491,e=0000000000236433705,k=8757,sxi=17,case=obj(10846),kb=ww_english_add,varset=ws:http://us.creative.com|title=Creative Worldwide Support|website=Support.creative.com|access-date=12 July 2016}}</ref>\n\nIn spite of these limitations, in less than a year, the Sound Blaster became the top-selling expansion card for the PC. It achieved this by providing a fully AdLib-compatible product, with additional features, for the same, and often a lower price. The inclusion of the [[game port]], and its importance to its early success, is often forgotten or overlooked. PCs of this era did not include a game port. Game port cards were costly (around $50) and used one of the few expansion slots PCs had at the time. Given the choice between an AdLib card or a fully compatible Sound Blaster card that came with a game port, saved a slot, and included the "DSP" for not much more in price, many consumers opted for the Sound Blaster. In-game support for the digital portion of the card did not happen until after the Sound Blaster had gained dominance.\n\nWhen Microsoft announced [[Multimedia PC]] (MPC) in November 1990, it suggested to developers that they use the Sound Blaster as it was the only sound card that came close to complying with the MPC standard. The press speculated that Microsoft based the MPC standard on the Sound Blaster's specifications.<ref name="english199206">{{cite news | url=http://www.atarimagazines.com/compute/issue141/82_Sound_Blaster_turns_.php | title=Sound Blaster turns Pro | work=Compute! | date=June 1992 | access-date=11 November 2013 | author=English, David | page=82}}</ref> By 1993 ''Computer Gaming World'' wondered "why would a gamer" buy a competing AdLib card that was not Sound Blaster-compatible.<ref name="cgw199310">{{cite news | url=http://www.cgwmuseum.org/galleries/index.php?year=1993&pub=2&id=111 | title=CGW Sound Card Survey | work=Computer Gaming World | date=October 1993 | access-date=26 March 2016 |author1=Weksler, Mike |author2=McGee, Joe | pages=76\u201383}}</ref> Creative advertised the Sound Blaster 16 ("the 16-bit sound standard") with the slogan "Get Real", emphasizing its "real 100% Sound Blaster compatibility" and rhetorically asking "why those other manufacturers spend so much time comparing themselves to Sound Blaster".<ref name="creative199312">{{cite news | url=http://www.cgwmuseum.org/galleries/index.php?year=1993&pub=2&id=113 | title=Bumper Crop | work=Computer Gaming World | date=December 1993 | access-date=29 March 2016 | type=advertisement | page=131}}</ref>\n\n ''[[Compute!]]'' in 1989 stated that with Sound Blaster, "IBM-compatible computers have taken the lead in sound and music for personal computers". Naming it a Compute! Choice, the magazine described the quality of the opening music of ''[[Space Quest III]]'' with the card as "extraordinary", praising the quality compared to the [[Roland MT-32]] and Ad Lib versions. ''Compute!'' approved of the card's [[direct memory access|DMA]] and Creative's dissemination of technical information, and concluded that while the more-expensive MT-32 was superior, Sound Blaster's audio quality was better than that of Ad Lib or Game Blaster.<ref name="leinecker198912">{{Cite magazine |last=Leinecker |first=Richard |date=December 1989 |title=Blast the PC Sound Barrier with this Creative Card |url=https://archive.org/stream/1989-12-compute-magazine/Compute_Issue_115_1989_Dec#page/n89/mode/2up |magazine=Compute! |pages=88\u201390}}</ref>\n\n [[Image:Sound Blaster 8bit.JPG|thumb|Sound Blaster 1.5 (CT1320C); C/MS chip sockets (labeled U14, U15) seem empty.]]\n\nReleased in 1990, the Sound Blaster 1.5, CT1320C, dropped the C/MS chips, which were no longer popular with game developers. Instead, the board had two empty sockets, which could be user upgraded by purchasing the C/MS chips directly from Creative or Phillips SAA-1099s from another source.  Otherwise the card functions identically to the Sound Blaster 1.0.<ref>Sound Blaster Optional Hardware & Software Catalog, Creative Labs Inc. (Page 2)</ref> The CT1320U variety has the same layout as the CT1320C.<ref>{{cite web|url=http://electricdreams.ath.cx/card/creact1320u.jpg |title=Archived copy |access-date=2013-11-14 |url-status=dead |archive-url=https://web.archive.org/web/20131225010529/http://electricdreams.ath.cx/card/creact1320u.jpg |archive-date=2013-12-25 }}</ref>\n\n [[Image:KL Creative Labs Soundblaster 2.0 CT1350B.jpg|thumb|Sound Blaster 2.0 (CT1350B), without C/MS and FM chipset]]\n\nThe final revision of the original Sound Blaster, the Sound Blaster 2.0 was released in October 1991,<ref>{{cite web|url=http://ibm-pc.org/manuals/other/creative/SoundBlaster2.PDF |title=Sound Blaster |website=Ibm-pc.org |access-date=2016-07-17}}</ref><!-- page 3 --> CT1350, added support for "[[Intel 8237#Modes|auto-init]]" [[Direct memory access|DMA]], which assisted in producing a continuous loop of [[Double-buffering|double-buffered]] sound output. Similar to version 1.0 and 1.5, it used a 1-channel 8-bit DAC. However, the maximum sampling rate was increased to 44 kHz for playback, and 15 kHz for record. The DSP's MIDI UART was upgraded to [[full-duplex]] and offered [[time stamp]]ing features, but was not yet compatible with the [[MPU-401]] interface used by professional MIDI equipment. The Sound Blaster 2.0's [[Printed circuit board|PCB]]-layout used more highly integrated components, both shrinking the board's size and reducing manufacturing cost.\n\nOwners of previous revision Sound Blaster boards could upgrade their board by purchasing the V2.00 DSP chip from Creative Labs, and swapping the older DSP V1.0x with the newer replacement. The upgraded board gained the auto-init DMA and new MIDI capabilities of the Sound Blaster 2.0 but not the expanded sampling rates.  The upgrade was necessary for full compatibility with the [[Windows 3.0]] Multimedia Extensions upgrade.\n\n [[File:SoundBlaster MCV CT5320B.jpg|thumb|right|The Sound Blaster MCV (CT5320B); note that the card has a greater width and thus lacks the typical MCA sled.]]\n\nSound Blaster MCV, CT5320, was a version created for [[IBM]] [[IBM Personal System/2|PS/2]] model 50 and higher and their ISA-incompatible [[Micro Channel architecture]]. The MCV Sound Blaster has some issues outputting audio while running on PS/2s with CPUs running faster than 16 MHz. However, the joystick interface is still inoperable on PS/2s it was designed for due to the slow-speed Schottky chips that have been installed. None of these timing issues affect the Yamaha YM3812. Some of the MCV Sound Blasters were released with faster Schottkys which eradicated some of the problems.<ref>{{cite web|url=http://ps-2.kev009.com/ohlandl/sound/Soundblaster.html|title=Soundblaster MCV|website=Ps-2.kev009.com|access-date=12 July 2016}}</ref>", "Sound Blaster --- Introduction ---|Second-generation Sound Blasters, 16-bit ISA & MCA cards": "[[Image:CT1330A.jpg|thumb|Sound Blaster Pro (CT1330A) rev.4]]Model CT1330, announced in May 1991, was the first significant redesign of the card's core features, and complied with the Microsoft MPC standard.{{r|english199206}}. The Sound Blaster Pro supported faster digital input and output sampling rates (up to 22.05 kHz stereo or 44.1 kHz mono), added a "[[Sound card mixer|mixer]]" to provide a crude master volume control (independent of the volume of sound sources feeding the mixer), and a crude high pass or low pass filter. The Sound Blaster Pro used a pair of [[Yamaha YM3812|YM3812]] chips to provide stereo music-synthesis (one for each channel). The Sound Blaster Pro was fully backward compatible with the original Sound Blaster line, and by extension, the [[AdLib]] sound card. The Sound Blaster Pro was the first Creative sound card to have a built-in [[CD-ROM]] interface. Most Sound Blaster Pro cards featured a proprietary interface for a [[Panasonic]] ([[Panasonic CD interface|Matsushita MKE]]) drive.  The Sound Blaster Pro cards are basically 8-bit ISA cards, they use only the lower 8 data bits of the ISA bus.  While at first glance it appears to be a 16-bit ISA card, it does not have 'fingers' for data transfer on the higher "AT" portion of the bus connector.  It uses the 16-bit extension to the ISA bus to provide the user with an additional choice for an IRQ (10) and DMA (0)m channel only found on the 16-bit portion of the edge connector.\n\nA short lived joint developed project between Creative and Tandy resulted in the Creative/Tandy Multimedia Sound Adapter, 849\u20133030. This Sound Blaster Pro derived card was factory installed in Tandy Multimedia PCs. It combined the CT1330 with Tandy joystick and MIDI ports (not MPU-401 compatible).<ref>{{cite web|url=http://www.vintage-computer.com/vcforum/showthread.php?46895-Creative-Tandy-Multimedia-Sound-Adapter-849-3030|title=Creative/Tandy Multimedia Sound Adapter, 849-3030|website=Vintage-computer.com|access-date=12 July 2016}}</ref>\n\n [[Image:Ct1600.jpg|thumb|Sound Blaster Pro 2 (CT1600)]]\n\nThe revised version, the Sound Blaster Pro 2, CT1600, replaced the YM3812s with a more advanced Yamaha [[YMF262]] (''OPL3'').  Otherwise it is functionally identical to the original Sound Blaster Pro.  Shortly after the release of the Sound Blaster Pro 2 version, Creative discontinued the original Sound Blaster Pro.\n\nThe Sound Blaster Pro 2 was also sold with the following on-board [[CD-ROM]] controllers:\n*Sound Blaster Pro 2, [[SCSI]], CT1610\n*Sound Blaster Pro 2, [[Laser Magnetic Storage International|LMSI]], CT1620\n*Sound Blaster Pro 2, [[Sony]], CT1690\n*Sound Blaster Pro 2, [[Mitsumi]], CT2600\n\nPackaged Sound Blaster cards were initially marketed and sold into the retail-channel. Creative's domination of the PC audiocard business soon had them selling the Sound Blaster Pro 2 [[Original equipment manufacturer|OEM]], CT1680, to customers for integration into pre-assembled PCs.\n\nCreative also sold Multimedia Upgrade Kits containing the Sound Blaster Pro. The kit bundled the sound card, a Matsushita CD-ROM drive (model 531 for single-speed, or 562/3 for the later double-speed (2x) drives), and several CD-ROMs of multimedia software titles. As CD-ROM technology was new, the kit included CD-ROM software, representing a very good value to customers. One such kit, named "OmniCD", included the 2x Matsushita drive along with an ISA controller card and software, including [[The Software Toolworks|Software Toolworks]] Encyclopedia and [[Aldus PhotoStyler]] SE. It was compliant with the [[Multimedia PC|MPC Level 2]] standard.\n\n The Sound Blaster Pro 2 MCV, CT5330, was a version created for [[IBM]] [[IBM Personal System/2|PS/2]] model 50 and higher and their [[MicroChannel]] bus.", "Sound Blaster --- Introduction ---|Third generation Sound Blasters, 16-bit ISA cards": "[[Image:SB16-CT2940.JPG|thumb|Sound Blaster 16 (CT2940)]]\n{{main|Sound Blaster 16}}\n\nThe next model, the Sound Blaster 16, announced in June 1992, introduced:\n*16-bit [[Compact Disc|CD-quality]] [[digital audio]];\n*An [[MPU-401]] compatible [[UART]] via [[game port]];\n*A connector for the [[Creative Wave Blaster|Wave Blaster]], a '[[Table-lookup synthesis|Wavetable]]' daughterboard ([[Wavetable synthesis]]).\nEventually this design proved so popular that Creative made a PCI version of this card. Creative's audio revenue grew from US$40 million per year to nearly US$1 billion following the launch of the Sound Blaster 16 and related products. Rich Sorkin was General Manager of the global business during this time, responsible for product planning, product management, marketing and OEM sales. Moving the card off the ISA bus, which was already approaching obsolescence, this meant that no line for host-controlled ISA DMA was available, as the PCI slot offers no such line. Instead, the card used PCI [[bus mastering]] to transfer data from the main memory to the D/A converters. Since existing DOS programs expected to be able to initiate host-controlled ISA DMA for producing sound, backward compatibility with the older Sound Blaster cards for DOS programs required a software driver work-around; since this work-around necessarily depended on the [[virtual 8086 mode]] of the PC's CPU in order to catch and reroute accesses from the ISA [[DMA controller]] to the card itself, it failed for a number of DOS games that either were not fully compatible with this CPU mode or needed so much free [[conventional memory]] that they could not be loaded with the driver occupying part of this memory. In [[Microsoft Windows]], there was no problem, as Creative's Windows driver software could handle both ISA and PCI cards correctly.\n\n \n[[Image:MediaForte SoundForte RadioPlus SF16-FMP2.jpg|thumb|Vibra based card with [[FM broadcasting|FM]] radio: SoundForte RadioPlus SF16-FMP2 by MediaForte]]\n\nThe Sound Blaster ViBRA16 was an inexpensive single-chip implementation of the [[Sound Blaster 16]] for the [[Original equipment manufacturer|OEM]] market. Creative Labs also used this chip for the Sound Blaster 32, Phone Blaster and Phone Blaster 28.8 (VIBRA + modem, CT3120 and CT3220.) and many other value-edition cards. External Yamaha OPL3 FM music synthesis was retained in earlier boards built around the ViBRA16 or ViBRA16s controllers, whilst the later (and more common) ViBRA16 boards used CQM (Creative Quadratic Modulation) developed by [[E-mu Systems]]. This series included the ViBRA16 (CT2501), ViBRA16s (CT2502, CT2504), ViBRA16c (CT2505) [[Legacy Plug and Play|PnP]] and ViBRA16XV (CT2511) chips. The primary advantage of the ViBRA16 was the inclusion of a 14.4 kbit/s telephony Modem; it also functioned as a telephone.", "Sound Blaster --- Introduction ---|Fourth generation Sound Blasters, 16-bit ISA cards, dynamic sample-based synthesis": "[[Image:Creative_Sound_Blaster_AWE32_PNP_CT3990.jpg|thumb|Sound Blaster AWE32 (CT3990)]]\n{{main|Sound Blaster AWE32}}\n\nReleased in March 1994, the ''Sound Blaster AWE32 (Advanced WavEffects)'' introduced an all new MIDI synthesizer section based on the EMU8000. The ''AWE32'' consisted of two distinct audio sections; the Creative digital audio section (audio [[codec]], optional CSP/ASP chip socket, Yamaha OPL3), and the [[E-mu]] MIDI synthesizer section. The synthesizer section consisted of the EMU8000 sampler and effects processor, an EMU8011 1 [[Megabyte|MB]] sample ROM, and 512 [[kilobyte|KB]] of sample RAM (expandable to 28 MB). To fit the new hardware, the AWE32 was a full-length [[Industry standard architecture|ISA]] card, measuring {{convert|14|in|mm|abbr=on}}.\n\n [[Image:Soundblaster32.jpg|thumb|Sound Blaster 32 ISA (CT3930)]]\n\nA derivative of the AWE32 design, the ''Sound Blaster 32'' (SB32) was a value-oriented offering from Creative. Announced on June 6, 1995, the SB32 became the new entry-level card in the AWE32 product-line (previously held by the ''AWE32 Value''.) The SB32 retained the AWE32's EMU8000/EMU8011 MIDI-synthesis engine and built-in instrument ROM, but dropped the onboard [[RAM]], the [[Creative Wave Blaster|Wave Blaster]] header, and the CSP port. The SB32 used the ''Vibra'' chip to reduce component count, which meant bass/treble/gain control was limited compared to the AWE32. The loss of onboard RAM is offset by the inclusion of [[SIMM|30-pin SIMM]] RAM sockets, which allow up to 28 MB RAM to be installed and used by the EMU engine.\n\n [[Image:KL Creative Labs Soundblaster AWE64 Gold CT4390.jpg|thumb|Sound Blaster AWE64 Gold (CT4390)]]\n{{main|Sound Blaster AWE64}}\n\nThe AWE32's successor, the ''Sound Blaster AWE64'' (November 1996), was significantly smaller, being a "half-length [[Industry Standard Architecture|ISA]] card" (that term is misleading \u2014 see the pictures for size comparison). It offered similar features to the AWE32, but also had a few notable improvements, including support for greater [[polyphony]], although this was a product of 32 extra software-emulated channels. The 30-pin [[SIMM]] slots from AWE32/SB32 were replaced with a proprietary memory format which could be (expensively) purchased from Creative.\n\nThe main improvements were better compatibility with older SB models, and an improved [[signal-to-noise ratio]]. The AWE64 came in two versions: A standard version (later rebranded as ''Value'') with 512{{nbsp}}KB of RAM and a Gold version with 4 MB of RAM and a separate [[SPDIF|S/PDIF]] output.", "Sound Blaster --- Introduction ---|Fifth generation Sound Blasters, PCI cards, multi-channel and F/X": "{{main|Ensoniq AudioPCI}}\n[[Image:Audiopci.jpg|thumb|Ensoniq AudioPCI]]\n\nIn 1998, Creative acquired [[Ensoniq Corporation]], manufacturer of the AudioPCI, a card popular with [[Original equipment manufacturer|OEM]]s at the time. It was a full-featured solution with [[Table-lookup synthesis|wavetable]] MIDI ([[sample-based synthesis|sample-based synthesizer]]), 4-speaker [[DirectSound3D]] surround sound, [[A3D]] emulation, and [[DOS]] [[legacy support]] via a [[terminate-and-stay-resident program]] program. It was cheap due to lack of hardware acceleration. It is full-duplex but at least in MS Windows cannot play back several sources at once.\n\nCreative released many cards using the original AudioPCI chip, [[Ensoniq ES1370]], and several boards using revised versions of this chip ([[ES1371]] and [[ES1373]]), and some with Creative-labeled AudioPCI chips. Boards using AudioPCI tech are usually easily identifiable by the board design and the chip size because they all look quite similar. Such boards include '''Sound Blaster PCI64''' (April 1998), '''PCI128''' (July 1998), '''Creative Ensoniq AudioPCI''', '''Vibra PCI''' and '''Sound Blaster 16 PCI'''.\n\nAn ES137x chip contains 3 stereo sample rate converters, some buffers and a PCI busmaster interface. Analogue interfacing is done by a codec chip, which runs at a fixed sampling frequency of 44 (Ensoniq Audio PCI) or 48 kHz (Creative's versions). (ISA soundcards had not resampled but switched between different time bases.) ES137x do not support [[SoundFont]]s but a filter-less MIDI engine with [[Table-lookup synthesis|wavetable]] ([[sample-based synthesis|sample]] table) sets of 2, 4, and 8{{nbsp}}MB size.\n\n {{main|Sound Blaster Live!}}\n[[Image:Sblive!.jpg|thumb|right|Sound Blaster Live! (CT4830)]]\n\nWhen the ''Sound Blaster Live!'' was introduced in August 1998, the use of a programmable [[digital signal processor]] in PC-audio was not unprecedented, as IBM had already done that with cheap [[Mwave]] sound- & modem-cards and [[Turtle Beach Systems|Turtle Beach]] with their professional Hurricane soundcards.\n\nThe Live! was built around Creative's new EMU10K1 chip, which contained 2.44 million transistors and was advertised of processing a flashy 1,000 [[million instructions per second|MIPS]]. The EMU10K1 (and its successors) did not use on-card RAM/ROM storage for instrument samples, instead it used a PCI busmaster interface to access sample-data stored in the host-PC's system memory. A/D- and D/A- converters as well as analogue mixing is done by an AC'97 chip running at 48 kHz sampling rate. All members of the SB Live! family have at least four-channel analog audio outputs and a 15-pin MIDI/Joystick multiport.\n\nFor game titles, ''EAX'' 1.0 (and later 2.0) ([[environmental audio extensions]], which briefly competed with the now defunct [[A3D|A3D 2.0]]) added hardware-accelerated acoustic effects. The EMU10K1 provided high-quality 64-voice [[Sample-based synthesis|sample-based synthesizer]] (a.k.a. [[Table-lookup synthesis|wavetable]]), with self-produced or third-party customized patches or "Soundfonts", and the ability to resample the audio output as input and apply a range of real-time DSP effects to any set of audio [[subchannel]]s present in the device.\n\nThe first model and flagship of the SB/Live family was the ''SB Live! Gold''. Featuring gold tracings on all major analog traces and external sockets, an [[Electromagnetic interference|EMI]]-suppressing printed circuit board [[Printed circuit board|substrate]] and [[lacquer]], the Gold came standard with a daughterboard that implemented a separate 4-channel alternative [[Mini-DIN connector|mini-DIN]] digital output to Creative-branded internal-[[Digital-to-analog converter|DAC]] speaker sets, a S/P-DIF digital audio Input and Output with separate software mappings, and a fully decoded MIDI interface with separate Input and Output (along with on mini-DIN converter.) The Gold highlighted many features aimed at music composition; ease-of-use ([[plug-and-play]] for musicians), realtime loopback-recording of the MIDI-synthesizer (with full freedom of Soundfonts, and environmental effects such as reverb, etc.), and bundled MIDI-software.\n\nThe mainstream model was the ''Sound Blaster Live!'' Like the Gold, the Live featured multi-speaker analog output (up to four channels), and identical music/sound generation capabilities (without the bundled MIDI software and interfacing-equipment.)\n\nLater versions of the Live!, usually called ''Live! 5.1'', offered 5.1-channel support which adds a [[center channel]] speaker and [[Low-frequency effects|LFE]] subwoofer output, most useful for movie watching. The Live! 5.1 could also use one of the 3.5 mm jack ports as an SPDIF out, which allowed the connection of an external decoder.\n\nCreative also released a ''Sound Blaster Live! Player 1024'' edition, which is identical to the regular ''Sound Blaster Live!'', but with the addition of some extra software.\n\n The ''Sound Blaster PCI 512'' (CT4790) is an EMU10K1-based sound card designed to fill a lower cost segment than the Live! Value. It is capable of most of the Live! Value's features aside from being limited to 512 MIDI voice polyphony (a software-based limitation), lacking digital [[Input/output|I/O]], removal of expansion [[Electrical connector|headers]], and only stereo or [[quadraphonic]] output support. The card's circuit layout is somewhat simpler than that of the Live! series.<ref>{{cite web|url=https://www.amazon.com/dp/B00004Z7EF|title=Creative Labs Sound Blaster PCI 512 Sound Card|access-date=12 July 2016|website=Amazon.com}}</ref><ref>[http://www.pcpro.co.uk/labs/2548/creative-sound-blaster-pci512.html ]{{dead link|date=July 2016}}</ref>\n\n {{main|Sound Blaster Audigy}}\n[[Image:Creative Sound Blaster Audigy SB0090.jpg|thumb|''Sound Blaster Audigy Player'']]\n\nThe ''Sound Blaster Audigy'' (August 2001) featured the Audigy processor (EMU10K2), an improved version of the EMU10K1 processor that shipped with the ''Sound Blaster Live!''. The Audigy could process up to four EAX environments simultaneously with its upgraded on-chip DSP and native [[Environmental audio extensions|EAX 3.0 ADVANCED HD]] support, and supported up to 5.1-channel output.\n\nThe Audigy was controversially advertised as a 24-bit sound card. The EMU10K2's audio transport (DMA engine) was fixed at 16-bit sample precision at 48 kHz (like the EMU10K1 in the original Live!), and all audio had to be resampled to 48 kHz in order to be accepted by the DSP (for recording or rendering to output.)\n\n''Sound Blaster Audigy 2'' (September 2002) featured an updated EMU10K2 processor, sometimes referred to as EMU10K2.5, with an improved DMA engine capable of 24-bit precision. Up to 192 kHz was supported for stereo playback/record, while 6.1 was capped at 96 kHz. In addition, Audigy 2 supported up to 6.1 (later [[7.1 surround sound|7.1]]) speakers and had improved [[signal-to-noise ratio]] (SNR) over the Audigy (106 vs. 100 [[decibels]] ([[A-weighting|A]])). It also featured built-in [[Dolby Digital|Dolby Digital EX]] 6.1 and 7.1 decoding for improved DVD play-back. The Audigy 2 line were the first sound cards to receive [[THX]] certification.\n\n''Sound Blaster Audigy 2 ZS'' (September 2003) is essentially an Audigy 2 with updated DAC and [[Operational amplifier|op-amps]]. Audigy 2 ZS uses the [[Cirrus Logic]] CS4382 DAC together with the op-amps and can produce an output SNR of 108 dB. There were a few slight [[printed circuit board]] modifications and [[7.1 surround sound|7.1]] audio support was added.\n\n''Sound Blaster Audigy 4 Pro'' (November 2004)<ref>{{cite web|url=http://reviews.cnet.com/sound-cards/creative-sound-blaster-audigy/4505-9334_7-31229395.html|title=Creative Sound Blaster Audigy 4 Pro|website=Reviews.cnet.com|access-date=12 July 2016}}</ref> was an Audigy 2 ZS with updated DACs and [[Analog-to-digital converter|ADCs]], the new DAC being the Cirrus Logic CS4398, boosting the output SNR to 113 dB.  Other than a [[breakout box]], it has no distinguishable difference from the Audigy 2 ZS.  The DSP is identical to the Audigy 2 ZS's but Creative put an "Audigy 4" sticker to cover the chip, making it appear as if it is a new chip. The Audigy 4 Pro is not to be confused with the Audigy 4 (Value) which contains lower quality DACs and does not have golden plated jacks. The Audigy 4 (Value) is more in line with the Audigy 2 Value series. The Audigy 4 had a shorter life span than its predecessors, due to the short window between it and the next-generation Sound Blaster X-Fi.\n\n''Sound Blaster Audigy Rx'' (September 2013) is similar to the ''Audigy 4'' but with a dedicated 600-ohm headphone amplifier and a [[PCIe]] 1x interface.<ref>{{cite web |url=http://us.store.creative.com/Sound-Blaster-Audigy-RX/M/B00EO6X7PG.htm |title=Archived copy |access-date=2013-09-23 |url-status=dead |archive-url=https://web.archive.org/web/20130928061052/http://us.store.creative.com/Sound-Blaster-Audigy-RX/M/B00EO6X7PG.htm |archive-date=2013-09-28 }}</ref> \n\n''Sound Blaster Audigy Fx'' (September 2013) also features a 600-ohm amplifier and a PCIe interface, but lacks the EMU10K DSP.<ref>{{cite web |url=http://us.store.creative.com/Sound-Blaster-Audigy-Fx/M/B00EO6X4XG.htm |title=Archived copy |access-date=2013-09-23 |url-status=dead |archive-url=https://web.archive.org/web/20130929170447/http://us.store.creative.com/Sound-Blaster-Audigy-Fx/M/B00EO6X4XG.htm |archive-date=2013-09-29 }}</ref>\n\n {{main|Sound Blaster X-Fi}}\n[[Image:Creative SB X-Fi Fatal1ty-AB.jpg|thumb|''Sound Blaster X-Fi XtremeGamer Fatal1ty Pro'']]\n\nThe ''X-Fi'' (for "Extreme Fidelity") was released in August 2005 and {{As of|2012|lc=on}} came in ''XtremeGamer'', ''Titanium'', ''Titanium Fatal1ty Professional'', ''Titanium Fatal1ty Champion'' and ''Elite Pro'' configurations. The 130 [[nanometer|nm]] [[EMU20K]]1 (or EMU20K2 for Titanium series models) audio chip operates at 400 [[Megahertz|MHz]] and has 51 million [[transistor]]s. The computational power of this processor, i.e. its performance, is estimated as 10,000 MIPS, which is about 24 times higher than the estimated performance of its predecessor, the Audigy processor. Beginning with the 2008 Titanium models, newer X-Fi cards switched from PCI to [[PCI Express]] x1 connectors. With the X-Fi's "Active Modal Architecture" (AMA), the user can choose one of three optimization modes: Gaming, Entertainment, and Creation; each enabling a combination of the features of the chipset. The X-Fi uses [[environmental audio extensions|EAX]] 5.0 which supports up to 128 3D-positioned voices with up to four effects applied to each. This release also included the 24-bit crystallizer, which is intended to pronounce percussion elements by placing some emphasis on low and high pitched parts of the sound. The X-Fi, at its release, offered some of the most powerful mixing capabilities available, making it a powerful entry-level card for home musicians. The other big improvement in the X-Fi over the previous Audigy designs was the complete overhaul of the resampling engine on the card. The previous Audigy cards had their DSPs locked at 48/16, meaning any content that did not match was resampled on the card in hardware; which was done poorly and resulted in a lot of intermodulation distortion. Many hardcore users worked around this by means of resampling their content using high quality software decoders, usually in the form of a plugin in their media player. Creative completely re-wrote the resampling method used on the X-Fi and dedicated more than half of the power of the DSP to the process; resulting in a very clean resample.{{Citation needed|date=March 2009}}", "Sound Blaster --- Introduction ---|Sixth generation Sound Blaster ''Sound Core3D'' cards": "[[File:Sound Blaster Recon3D.jpg|thumb|Sound Blaster Recon3D]]\n\nThe Recon3D series was announced in September 2011 and includes the ''Recon3D PCIe'', ''Recon3D Fatal1ty Professional'' and ''Recon3D Fatal1ty Champion''. The cards use the new integrated ''Sound Core3D'' chip, which features the ''Quartet DSP'' from the X-Fi series as well as integrated DAC, ADC and I/O interface in a 56-pin package.<ref>{{cite press release|url=http://www.creative.com/corporate/pressroom/releases/welcome.asp?pid=13247|title=CREATIVE UNLEASHES SOUND BLASTER RECON3D - A NEW AUDIO PLATFORM POWERED BY SOUND CORE3D - THE WORLD'S FIRST QUAD-CORE AUDIO AND VOICE PROCESSOR|publisher=Creative Technology Ltd|date=2011-09-01|access-date=2013-05-10|url-status=dead|archive-url=https://web.archive.org/web/20130204171517/http://www.creative.com/corporate/pressroom/releases/welcome.asp?pid=13247|archive-date=2013-02-04}}</ref> The Asia-only ''Recon3D Professional Audio'' is basically a ''Recon3D PCIe'' with some extra accessories such as cables.<ref>{{cite web|url=http://asia.creative.com/products/product.asp?category=1&subcategory=872&product=21116 |title=Sound Blaster Recon3D Professional Audio Sound Card |publisher=Asia.creative.com |date=2012-09-16 |access-date=2013-02-13}}</ref>\n\nThe Recon3D series of sound cards do not support [[Audio Stream Input/Output|ASIO]].<ref>{{cite web|url=http://support.creative.com/kb/ShowArticle.aspx?sid=7358|title=Creative Worldwide Support|website=Support.creative.com|access-date=12 July 2016}}</ref>\n\nThe Recon3D comes with a bundled software called the SBX Pro Studio. SBX Pro Studio allows users to adjust the amount of virtual Surround, Crystallizer, Bass, Smart Volume and Dialog Plus for their Recon3D sound cards.<ref>{{cite web|url=http://www.techpowerup.com/185395/creative-revises-sound-blaster-recon3d-with-sbx-pro-studio.html|title=Creative Revises Sound Blaster Recon3D with SBX Pro Studio|website=Techpowerup.com|access-date=12 July 2016}}</ref> The Recon3D also has got the Crystal Voice feature that reduces the pickup of background noises like the hairdryer or vacuum cleaner when a beamforming microphone is used.<ref>{{cite web|url=http://www.creative.com/audiomadeclever/what-is-crystalvoice|title=Audio Made Clever :: What is CrystalVoice?|website=Creative.com|access-date=12 July 2016}}</ref>\n\nReviews have been generally positive, but pricing and small model differences have raised questions. Especially the low and mid priced models ''Recon3D PCIe'' and ''Recon3D Fatal1ty Professional'' have only cosmetic differences, but considerable price difference: the ''Fatal1ty Professional'', adds a beamforming microphone, some red LED lights and a metal shroud over the board, but has no real hardware improvements.<ref>{{cite web|url=http://www.expertreviews.co.uk/gadgets/1291081/creative-labs-sound-blaster-recon3d-pcie-fatal1ty-professional |title=Creative Labs Sound Blaster Recon3D PCIe Fatal1ty Professional review |publisher=Expert Reviews |access-date=2013-02-13}}</ref><ref>{{cite web|url=http://compreviews.about.com/od/multimedia/fr/Creative-Sound-Blaster-Recon3D-Fatal1ty-Professional.htm |title=Creative Sound Blaster Recon3D Fatal1ty Professional PCI-Express Sound Card Review |publisher=Compreviews.about.com |date=2012-02-01 |access-date=2013-02-13}}</ref>\n\n The Sound Blaster Z-Series was announced in August 2012 and includes the [[PCI Express]] x1 cards, ''Z'', ''Zx'' and ''ZxR'' which use the same ''Sound Core3D'' chip as the previous Sound Blaster Recon3D series.<ref name="Creative Technology Ltd">{{cite press release|url=http://www.creative.com/corporate/pressroom/releases/welcome.asp?pid=13285|title=CREATIVE INTRODUCES THE SOUND BLASTER Z-SERIES - A NEW RANGE OF ULTRA HIGH-PERFORMANCE SOUND CARDS DESIGNED FOR FUTURE GAMING AND ENTERTAINMENT AUDIOR|publisher=Creative Technology Ltd|date=2011-08-15|access-date=2013-05-10|url-status=dead|archive-url=https://web.archive.org/web/20130510123813/http://www.creative.com/corporate/pressroom/releases/welcome.asp?pid=13285|archive-date=2013-05-10}}</ref>  The Z-Series improved sound quality over the Recon3D series by including more dedicated audio hardware such as [[Operational amplifier|Op-Amps]], [[Digital-to-analog converter|DACs]], and [[Analog-to-digital converter|ADCs]].<ref>{{cite web|url=http://www.custompcreview.com/reviews/creative-sound-blaster-zxr-review/17756/|title=Creative Sound Blaster ZxR PCIe Sound Card Review|date=2013-04-08|access-date=2013-05-10}}</ref>\n[[File:A photo of a Sound Blaster Z sound card.jpg|thumb|A Sound Blaster Z sound card]]\n* The ''Sound Blaster Z'' is the baseline card of the series.  Some of its main features are Cirrus Logic 116 dB signal-to-noise ratio (SNR) digital-to-analog converters (DACs), a dedicated headphone jack with 600 ohm amplifier, and is bundled with a ''Beamforming Microphone'' that captures sound in a specific direction.  One can switch between listening with headphones and desktop speakers in the Sound Blaster Z Control Panel.  This card has a red color theme with a red LED light on the board.  In addition to the red model, there is an OEM version that lacks the LED light, metal shielding and bundled microphone.\n* The Sound Blaster Zx card is identical to the Z<ref name="Creative Technology Ltd"/> (exact same card, exact same card SKU/Model (SB1500) on card itself, compared side by side in store), with the only notable change compared to the baseline "Z" being the addition of the desktop ACM (Audio Control Module). The Zx & ZxR were both bundled with the Audio Control Module (ACM) which is basically an extension cord for headphones. The ACM contains both 1/4" and 3.5mm headphone and microphone jacks, a potentiometer headphone volume knob, and a built-in dual-microphone Beamforming array. The ACM uses a red color theme that matches the card. The entire package (Card and ACM) carries a separate model number of SB1506, which is different than the base SB1500 printed on the included card (as the card is just a SB-Z now bundled with accessories).<ref>{{cite web|url=https://www.legitreviews.com/creative-sound-blaster-z-zx-sound-card-review_155705/2|title=Creative Sound Blaster Z and Zx Sound Card Review|date=2015-02-03|access-date=2019-05-14}}</ref>\n* The ''Sound Blaster ZxR'' is the top of line sound card of the series and uses an entirely different card from the Z and Zx.  Some of its features include TI [[Burr-Brown]] 124 dB SNR DACs, two swappable op-amps, a 600ohm 80 mW TI TPA6120 headphone amplifier, and 192 kHz stereo pass through. The ''Sound Blaster ZxR'' comes with a daughter board which provides optical [[S/PDIF]] input and output, and two [[RCA connector|RCA]] inputs that feature a TI Burr-Brown 123 dB SNR analog-to-digital converter (ADC); it has its own ''Sound Core3D'' processor and takes up a second expansion slot in the computer if installed.  The ''ZxR'' can record up to 24-bit/96 kHz.  The ACM and two boards (main and daughter) have a black color scheme with no LED lighting.\n\n The Sound BlasterX AE-5 was announced in June 2017, the first discrete sound card made by Creative in five years since the introduction of the Z-series. The card is the first in the Sound Blaster series to use a 32-bit/384 kHz SABRE 32 Ultra DAC (ES9016K2M), along with a custom-designed discrete headphone amplifier (1W output power and low output impedance of 1 Ohm so it can provide high damping factor for virtually any dynamic headphone). The card has an additional RGB lighting courtesy of a MOLEX power connection and accompanying RGB LED strip.<ref>{{cite magazine|url=https://www.pcworld.com/article/3200173/peripherals/hands-on-creative-labs-sound-blasterx-ae-5-ups-the-audio-for-gamers.html|title=Hands on: Creative Labs' Sound BlasterX AE-5 ups the audio for gamers |magazine=PC World |date=2017-06-12 |access-date=2017-11-03}}</ref><ref>{{cite web|url=https://us.creative.com/p/sound-cards/sound-blasterx-ae-5|title=Creative Sound BlasterX AE-5}}</ref> In late 2017, a white colored model of the sound card called the Sound BlasterX AE-5 Pure Edition was released with 4 RGB LED strips instead of one with the standard black model.<ref>{{cite web|url=https://us.creative.com/p/sound-cards/sound-blasterx-ae-5-pure-edition|title=Creative Sound BlasterX AE-5 Pure Edition}}</ref>\n\nIn 2020, the AE-5 Plus was released which is similar to the previous model, but the sound card comes with hardware Dolby Digital Live and DTS encoding.<ref>{{cite web|url=https://us.creative.com/p/sound-blaster/sound-blasterx-ae-5-plus|title=Creative Sound BlasterX AE-5 Plus}}</ref> There is a white colored Pure Edition released alongside the standard black model.<ref>{{cite web|url=https://us.creative.com/p/sound-blaster/sound-blasterx-ae-5-plus-pure-edition|title=Creative Sound BlasterX AE-5 Plus Pure Edition}}</ref>\n\n The Sound Blaster AE-7 was released in July 2019 alongside the Sound Blaster AE-9.<ref name=betanews_ae9-ae7/> It is equipped with an ESS SABRE 9018 DAC,<ref name="Sound Blaster AE-7">{{Cite web|url=https://us.creative.com/p/sound-cards/sound-blaster-ae-7|title=Sound Blaster AE-7|website=Creative Store - United States|language=en|access-date=2019-07-27}}</ref> and it features an ACM (Audio Control Module), which connects to the sound card via two of the audio ports available on the card itself.<ref name="Sound Blaster AE-7"/> It doesn't feature RGB lighting, contrary to the AE-5, and it doesn't require external power either.\n\n The Sound Blaster AE-9 was announced in December 2018, targeting the audiophile audience.<ref>{{Cite web|url=https://www.notebookcheck.net/Creative-Labs-showcases-new-Sound-BlasterX-AE-9-audiophile-soundcard.376156.0.html|title=Creative Labs showcases new Sound BlasterX AE-9 audiophile soundcard|last=Solca|first=Bogdan|website=Notebookcheck|language=en|access-date=2019-02-01}}</ref> This soundcard is equipped with an ESS SABRE 9038 DAC,<ref name="Sound Blaster AE-9">{{Cite web|url=https://us.creative.com/p/sound-cards/sound-blaster-ae-9|title=Sound Blaster AE-9|website=Creative Store - United States|language=en|access-date=2019-07-27}}</ref> and it features an external Audio Control Module which connects to the sound card with a mini-HDMI cable,<ref name="Sound Blaster AE-9"/> containing an XLR port for a microphone and a toggleable 48+volt phantom power rail; the sound card itself features replaceable operational amplifiers. The sound card with the external DAC consumes 75 W, and thus is the first sound card from Creative that requires auxiliary power, using a 6-pin [[PCI Express|PCI-E]] connector to supply power to the external DAC.\nThe card was officially released on July 10, 2019 to celebrate 30 years since the introduction of the original Sound Blaster.<ref name=betanews_ae9-ae7>{{Cite web|url=https://betanews.com/2019/07/09/creative-30-soundblaster-ae9-ae7/|title = Creative celebrates 30 years of Sound Blaster by launching AE-9 and AE-7 PCIe sound cards for audiophiles and gamers|date = 9 July 2019}}</ref>", "Sound Blaster --- Introduction ---|Sound BlasterX Series": "The Sound BlasterX series was announced at [[Gamescom]] 2015.<ref>{{cite web|url=http://www.vortez.net/news_story/creative_launch_sound_blaster_x_pro_gaming_audio_gear.html |title=Creative Launch Sound Blaster X - Pro Gaming Audio Gear |website=Vortez.net |access-date=2016-07-17}}</ref>\nThe Sound BlasterX brand consists of USB audio devices, gaming headsets, gaming mousepads, gaming speakers, a discrete sound card, a gaming mouse and a gaming keyboard.\n\n \n The Sound BlasterX H3, H5 and P5 come with the BlasterX Acoustic Engine Lite software. The BlasterX Acoustic Engine Lite software comes with preset audio profiles for different game types. The settings in the profiles are not adjustable unlike the BlasterX Acoustic Engine Pro.<ref>{{cite web|last=Wong |first=Marcus |url=http://www.hardwarezone.com.sg/tech-news-creative-s-new-sound-blasterx-gaming-headsets-bring-ultra-realistic-gaming-experiences-tod |title=Creative's new Sound BlasterX gaming headsets bring Ultra-realistic gaming experiences to today's gamers |website=HardwareZone.com.sg |access-date=2016-07-17}}</ref>\nThe BlasterX Acoustic Engine Lite software is only available for Windows PC.\n\n The BlasterX Acoustic Engine Pro allows users to adjust the amount of effects and save them. It also has Scout Mode and Voice FX. Users can bind key combinations to enable/disable BlasterX Acoustic Engine, Scout Mode and Voice FX.\n\nThere is also an equalizer tab in the software.<ref>{{cite web |url=http://www.pcgameware.co.uk/reviews/headsets/sound-blasterx-h7-headset-review/ |title=Sound BlasterX H7 Headset Review |website=Pcgameware.co.uk |date=2016-06-06 |access-date=2016-07-17 |archive-url=https://web.archive.org/web/20160716070717/http://www.pcgameware.co.uk/reviews/headsets/sound-blasterx-h7-headset-review/ |archive-date=2016-07-16 |url-status=dead }}</ref> Users can load profiles and create profiles in the equalizer.\nThe BlasterX Acoustic Engine Pro software is available only for Windows PC.\n\n The Sound BlasterX H3, Sound BlasterX H5 are headsets with 3.5mm audio jacks. The Sound BlasterX P5 is an earphone with an inline microphone. They come with an audio/mic splitter cable. The Sound BlasterX H3, H5 and P5 come with a software called the BlasterX Acoustic Engine Lite.\n\nThe Sound BlasterX H7 is a gaming headset with USB and 3.5mm jack connectivity. It has a maximum playback bitrate and sample rate at 24-bit / 96 kHz and supports 7.1 [[virtual surround]]. The Sound BlasterX H7 comes with the BlasterX Acoustic Engine Pro software.\n\n \n Unlike the Sound Blaster E5, it does not have built-in microphones, rechargeable battery and Bluetooth connectivity. BlasterX Acoustic Engine profiles can be saved onto the device in Windows and used on a Mac computer. There is no Mac OS X software as well as Android iOS apps for the Sound BlasterX G5.\n\n The Sound BlasterX G1 uses the BlasterX Acoustic Engine Pro software like the Sound BlasterX G5. It has 4-pole headphones and a microphone audio port. It has a maximum playback bitrate and sample rate at 24-bit / 96 kHz and supports 7.1 [[virtual surround]]. Its headphones amplifier supports headphones with impedances from 16 ohms to 300 ohms.<ref>{{cite web|author=Daniel Brown |url=http://www.wovow.org/sound-blasterx-g1-sound-card/ |title=Sound BlasterX G1: portable sound card for gamers |website=Wovow.org |date=2016-04-20 |access-date=2016-07-17}}</ref>\n\nThe Sound BlasterX G1 does not have the SB-Axx1 audio chip and is not able to save profiles from the BlasterX Acoustic Engine to the device. It is able to save profiles from the X-Plus Configurator running X-Plus Mode. The X-Plus Configurator software is only available for Windows PC.\n\nThe profiles in the X-Plus Configurator apply equalizer settings tuned for certain games.<ref>{{cite web|url=http://support.creative.com/kb/ShowArticle.aspx?sid=132199 |title=Creative Worldwide Support |website=Support.creative.com |access-date=2016-07-17}}</ref>\n\nThe Sound BlasterX G1 does not support "What U Hear"."}},
{"article_title": "Hydrogen vehicle", "pageid": "188545", "revid": "1062691624", "timestamp": "2021-12-29T23:47:53Z", "history_paths": [["Hydrogen vehicle --- Introduction ---"]], "categories": ["hydrogen vehicles", "automotive technologies", "sustainable technologies", "green vehicles", "hydrogen technologies", "hydrogen economy", "emerging technologies"], "heading_tree": {"Hydrogen vehicle --- Introduction ---": {"Vehicles": {"Automobiles": {"Auto racing": {}}, "Buses": {}, "Trams and trains": {}, "Ships": {}, "Bicycles": {}, "Military vehicles": {}, "Motorcycles and scooters": {}, "Auto rickshaws": {}, "Quads and tractors": {}, "Aeroplanes": {}, "Fork trucks": {}, "Rockets": {}, "Heavy trucks": {}}, "Internal combustion vehicle": {}, "Fuel cell": {"Fuel cell cost": {}, "Freezing conditions": {}, "Service life": {}}, "Hydrogen": {"Production": {}, "Storage": {}, "Infrastructure": {}, "Codes and standards": {}}, "Official support": {"U.S. initiatives": {}, "Other efforts": {}}, "Criticism": {}, "Safety and supply": {}, "Comparison with other types of alternative fuel vehicle": {"Plug-in hybrids": {}, "Natural gas": {}, "All-electric vehicles": {}}, "See also": {}, "References": {}, "External links": {}}}, "more_than_two_sections_excluding_boilerplate": true, "history_section_designated_exact": false, "history_section_designated_fuzzy": false, "history_section_non_designated": true, "history_section_texts": {"Hydrogen vehicle --- Introduction ---": "{{short description|Vehicle that uses hydrogen fuel for motive power}}\n[[File:Toyota FCV reveal 25 June 2014 - by Bertel Schmitt 02.jpg|thumb|300px|The 2015 [[Toyota Mirai]] is one of the first hydrogen [[fuel cell vehicle]]s to be sold commercially. The Mirai is based on the Toyota fuel cell vehicle (FCV) concept car (shown).<ref>{{cite web|url=http://transportevolved.com/2014/06/25/toyota-unveils-2015-fuel-cell-sedan-will-retail-japan-around-%C2%A57-million/|title=Toyota Unveils 2015 Fuel Cell Sedan, Will Retail in Japan For Around \u00a57 Million|publisher=transportevolved.com|date=2014-06-25|access-date=2014-06-26|archive-date=2018-11-19|archive-url=https://web.archive.org/web/20181119025848/https://transportevolved.com/2014/06/25/toyota-unveils-2015-fuel-cell-sedan-will-retail-japan-around-%C2%A57-million/|url-status=live}}</ref>]]\nA '''hydrogen vehicle''' is a type of [[alternative fuel vehicle]] that uses [[hydrogen fuel]] for [[Power (physics)|motive power]]. Hydrogen vehicles include hydrogen-fueled [[space rocket]]s, as well as [[automobile]]s and other transportation vehicles. Power is generated by converting the [[chemical energy]] of hydrogen to [[mechanical energy]], either by reacting hydrogen with oxygen in a [[fuel cell]] to power [[electric motor]]s or, less commonly, by burning [[Hydrogen internal combustion engine vehicle|hydrogen in an internal combustion engine]].<ref>{{cite web|url=http://www.iphe.net/docs/Resources/Power_trains_for_Europe.pdf|title=A portfolio of power-trains for Europe: a fact-based analysis|website=iphe.net|access-date=15 April 2018|archive-date=15 October 2017|archive-url=https://web.archive.org/web/20171015151243/https://www.iphe.net/docs/Resources/Power_trains_for_Europe.pdf|url-status=live}}</ref>\n\n{{asof|2021||df=}}, there are two models of hydrogen cars publicly available in select markets: the [[Toyota Mirai]] (2014\u2013), which is the world's first mass-produced dedicated [[Fuel Cell Electric Vehicle|fuel cell electric vehicle]] (FCEV), and the [[Hyundai Nexo]] (2018\u2013). The [[Honda Clarity]] was produced from 2016 to 2021.<ref name=HondaDiscontinued>{{cite web|url=https://www.autocar.co.uk/car-news/industry-news-manufacturing/honda-discontinues-hydrogen-fuelled-clarity-fcv-due-slow-sales | title= Honda discontinues hydrogen-fuelled Clarity FCV due to slow sales|date=June 16, 2021| access-date=July 29, 2021}}</ref> Most companies that had been testing hydrogen cars have switched to battery electric cars; [[Volkswagen]] has expressed that the technology has no future in the automotive space, mainly because a fuel cell electric vehicle consumes about three times more energy than a [[battery electric car]] for each mile driven. {{Asof|2020|12}}, there were 31,225 passenger [[fuel cell vehicle|FCEV]]s powered with hydrogen on the world's roads.<ref>{{cite web| url=https://www.iea.org/reports/global-ev-outlook-2021 | title=Global EV Outlook 2021: Accelerating ambitions despite the pandemic |author=International Energy Agency (IEA), Clean Energy Ministerial, and Electric Vehicles Initiative (EVI)  |publisher=[[International Energy Agency]] | date=2021-04-29 | access-date=2021-05-17}} Go to the [https://www.iea.org/articles/global-ev-data-explorer Global EV Data Explorer] tool and choose "EV Stock", "Cars" and "World" for global stock, and "Country" for the country stock.</ref>\n\nAs of 2019, 98% of hydrogen is produced by [[steam methane reforming]], which emits carbon monoxide.<ref name=Realising/> It can be produced by [[thermochemical]] or [[pyrolytic]] means using renewable [[feedstock]]s, but the processes are currently expensive.<ref name=Production>Romm, Joseph. [http://thinkprogress.org/climate/2014/08/05/3467115/tesla-toyota-hydrogen-cars-batteries/ Tesla Trumps Toyota: Why Hydrogen Cars Can\u2019t Compete With Pure Electric Cars"] {{Webarchive|url=https://web.archive.org/web/20140821024845/http://thinkprogress.org/climate/2014/08/05/3467115/tesla-toyota-hydrogen-cars-batteries/ |date=2014-08-21 }}, [[ThinkProgress]], August 5, 2014.</ref> Various technologies are being developed that aim to deliver costs low enough, and quantities great enough, to compete with hydrogen production using natural gas.<ref>{{cite web|url=http://www.nrel.gov/hydrogen/proj_wind_hydrogen.html|title=Wind-to-Hydrogen Project|date=September 2009|work=Hydrogen and Fuel Cells Research|publisher=National Renewable Energy Laboratory, U.S. Department of Energy|access-date=7 January 2010|location=Golden, CO|url-status=dead|archive-url=https://web.archive.org/web/20090826043817/http://nrel.gov/hydrogen/proj_wind_hydrogen.html|archive-date=26 August 2009}}. See also [http://energy.gov/articles/energy-department-launches-public-private-partnership-deploy-hydrogen-infrastructure Energy Department Launches Public-Private Partnership to Deploy Hydrogen Infrastructure] {{Webarchive|url=https://web.archive.org/web/20140607042446/http://energy.gov/articles/energy-department-launches-public-private-partnership-deploy-hydrogen-infrastructure |date=2014-06-07 }}, US Dept. of Energy, accessed November 15, 2014</ref>\n\nThe benefits of hydrogen technology are fast refueling time (comparable to gasoline) and long driving range on a single tank. The drawbacks of hydrogen use are high carbon emissions when hydrogen is produced from natural gas, capital cost burden, low energy content per unit volume at ambient conditions, production and compression of hydrogen, the investment required in [[filling station]]s to dispense hydrogen, transportation of hydrogen to filling stations, and lack of ability to produce or dispense hydrogen at home.<ref name="Berman2013">{{cite news| author=Berman, Bradley| url=https://www.nytimes.com/2013/11/24/automobiles/fuel-cells-at-center-stage.html?pagewanted=1&_r=1&adxnnlx=1385313339-SWDXRwwueS6Exot9wFmA%20Q| title=Fuel Cells at Center Stage| work=[[The New York Times]]| date=2013-11-22| access-date=2013-11-26| archive-date=2014-11-07| archive-url=https://web.archive.org/web/20141107163736/http://www.nytimes.com/2013/11/24/automobiles/fuel-cells-at-center-stage.html?pagewanted=1&_r=1&adxnnlx=1385313339-SWDXRwwueS6Exot9wFmA%20Q| url-status=live}}</ref><ref>{{cite news|author=Davies, Alex|url=http://www.businessinsider.com/honda-hydrogen-fuel-cell-car-future-la-auto-show-2013-11|title=Honda Is Working On Hydrogen Technology That Will Generate Power Inside Your Car|work=The Business Insider|date=2013-11-22|access-date=2013-11-26|archive-date=2013-11-25|archive-url=https://web.archive.org/web/20131125201804/http://www.businessinsider.com/honda-hydrogen-fuel-cell-car-future-la-auto-show-2013-11|url-status=live}}</ref><ref name="Cox2014">Cox, Julian. [http://cleantechnica.com/2014/06/04/hydrogen-fuel-cell-vehicles-about-not-clean "Time To Come Clean About Hydrogen Fuel Cell Vehicles"] {{Webarchive|url=https://web.archive.org/web/20140715023909/http://cleantechnica.com/2014/06/04/hydrogen-fuel-cell-vehicles-about-not-clean/ |date=2014-07-15 }}, CleanTechnica.com, June 4, 2014</ref>\n\n [[File:FCX Clarity.jpg|thumb|right|Honda [[FCX Clarity]], a hydrogen fuel cell demonstration vehicle introduced in 2008]]\n{{further|Fuel cell vehicle}}\nAutomobiles, [[Fuel cell bus|buses]], forklifts, [[Hydrail|trains]], [[PHB (bicycle)|PHB bicycles]], [[canal boat (hydrogen)|canal boats]], [[Freight bicycle (hydrogen)|cargo bikes]], [[golf cart]]s, [[ENV|motorcycles]], [[wheelchair (hydrogen)|wheelchairs]], [[Hydrogen ship|ships]], [[aeroplane]]s, [[submarine]]s, and [[rocket]]s can already run on hydrogen, in various forms. [[NASA]] used hydrogen to launch [[Space Shuttle]]s into space. A working toy model car runs on [[solar power]], using a [[regenerative fuel cell]] to store energy in the form of hydrogen and [[oxygen]] gas. It can then convert the fuel back into water to release the solar energy.<ref>[http://www.thamesandkosmos.com/products/fc/fc2.html Thames & Kosmos kit] {{webarchive|url=https://web.archive.org/web/20120712033119/http://www.thamesandkosmos.com/products/fc/fc2.html |date=2012-07-12 }}, [http://www.bpa.gov/Energy/N/projects/fuel_cell/education/fuelcellcar/index.cfm Other educational materials] {{Webarchive|url=https://web.archive.org/web/20090207185927/http://www.bpa.gov/Energy/N/projects/fuel_cell/education/fuelcellcar/index.cfm |date=2009-02-07 }}, and [http://www.fuelcellstore.com/cgi-bin/fuelweb/view=NavPage/cat=14 many more demonstration car kits] {{webarchive|url=https://web.archive.org/web/20071226113833/http://www.fuelcellstore.com/cgi-bin/fuelweb/view%3DNavPage/cat%3D14 |date=2007-12-26 }}.</ref> Since the advent of hydraulic fracturing the key concern for hydrogen fuel cell vehicles is consumer and public policy confusion concerning the adoption of natural gas powered hydrogen vehicles with heavy hidden emissions to the detriment of environmentally friendly transportation.<ref name=Cox2014/>\n\n {{asof|2021}}, there are two hydrogen cars publicly available in select markets: the [[Toyota Mirai]] and the [[Hyundai Nexo]].<ref name=ihs2016>{{cite web|url=http://press.ihs.com/press-release/automotive/global-hydrogen-fuel-cell-electric-vehicle-market-buoyed-oems-will-launch-1|title=Global Hydrogen Fuel Cell Electric Vehicle Market Buoyed as OEMs Will Launch 17 Vehicle Models by 2027, IHS Says|publisher=[[IHS Inc.]]|date=4 May 2016|access-date=13 May 2016|archive-date=2 March 2021|archive-url=https://web.archive.org/web/20210302032701/https://news.ihsmarkit.com/|url-status=live}}</ref> The [[Honda Clarity]] was produced from 2016 to 2021.<ref name=HondaDiscontinued/>\n\n[[File:Hyundai Nexo Genf 2018.jpg|thumb|left| The [[Hyundai Nexo]] is a hydrogen fuel cell-powered [[Crossover (automobile)|crossover SUV]]]]\nIn 2013 the [[Hyundai Tucson FCEV]] was launched, it was a conversion of the Tucson and available in left-hand drive only and became the first commercially mass-produced vehicle of its type in the world.<ref>{{cite news| url=http://www.businesskorea.co.kr/news/articleView.html?idxno=552| title=The World's First Mass-Production of FCEV| access-date=18 November 2018| archive-date=18 November 2018| archive-url=https://web.archive.org/web/20181118164724/http://www.businesskorea.co.kr/news/articleView.html?idxno=552| url-status=live}}</ref><ref>{{cite web| url=https://www.hyundainews.com/en-us/releases/1624| title=Hyundai ix35 Fuel Cell| publisher=Hyundai| access-date=18 November 2018| archive-date=18 November 2018| archive-url=https://web.archive.org/web/20181118171602/https://www.hyundainews.com/en-us/releases/1624| url-status=live}}</ref> [[Hyundai Nexo]], which succeeded the Tucson in 2018, was selected as the "safest SUV" by the Euro NCAP in 2018<ref>{{Cite web|url=https://www.euroncap.com:443/en/ratings-rewards/best-in-class-cars/2018|title=Euro NCAP Best in Class 2018 - new award for best performing hybrid & electric car of 2018 | Euro NCAP|website=www.euroncap.com|access-date=2019-06-24|archive-date=2019-06-24|archive-url=https://web.archive.org/web/20190624190214/https://www.euroncap.com/en/ratings-rewards/best-in-class-cars/2018|url-status=live}}</ref> and was rated as "Good" in a side crash test conducted by the Insurance Institute for Highway Safety (IIHS)<ref>{{Cite web|url=https://www.iihs.org/ratings/vehicle/hyundai/nexo-4-door-suv/2019|title=2019 Hyundai Nexo 4-door SUV|website=IIHS-HLDI crash testing and highway safety|access-date=2019-06-24|archive-date=2019-06-24|archive-url=https://web.archive.org/web/20190624090052/https://www.iihs.org/ratings/vehicle/hyundai/nexo-4-door-suv/2019|url-status=live}}</ref>\n\nToyota launched the world's first dedicated mass-produced fuel cell vehicle (FCV), the [[Toyota Mirai|Mirai]], in Japan at the end of 2014 and began sales in California, mainly the [[Los Angeles metropolitan area|Los Angeles area]] and also in selected markets in Europe, the UK, Germany and Denmark<ref>[https://insideevs.com/news/325606/european-sales-of-toyota-mirai-to-begin-this-september/ European Sales Of Toyota Mirai To Begin This September]</ref> later in 2015.<ref name=Voelcker>Voelcker, John. [https://autos.yahoo.com/news/decades-promises-dude-wheres-hydrogen-fuel-cell-car-130000421.html "Decades Of Promises: 'Dude, Where's My Hydrogen Fuel-Cell Car?'"] {{Webarchive|url=https://web.archive.org/web/20210302032700/https://autos.yahoo.com/news/decades-promises-dude-wheres-hydrogen-fuel-cell-car-130000421.html |date=2021-03-02 }}, Yahoo.com, March 31, 2015</ref> The car has a range of {{convert|312|mi|abbr=on}} and takes about five minutes to refill its hydrogen tank. The initial sale price in Japan was about 7 million yen ($69,000).<ref name="bloomberg.com">{{cite web|url=https://www.bloomberg.com/news/2014-06-25/toyota-to-offer-69-000-car-as-musk-pans-fool-cells-.html/|title=Toyota to Offer $69,000 Car After Musk Pans 'Fool Cells'|date=2014-06-25|access-date=2014-06-27|archive-date=2014-06-27|archive-url=https://web.archive.org/web/20140627055520/http://www.bloomberg.com/news/2014-06-25/toyota-to-offer-69-000-car-as-musk-pans-fool-cells-.html|url-status=live}}</ref> Former European Parliament President [[Pat Cox]] estimated that Toyota would initially lose about $100,000 on each Mirai sold.<ref name=Cost2014>Ayre, James. [http://cleantechnica.com/2014/11/19/toyota-lose-100000-every-hydrogen-fcv-sold/ "Toyota To Lose $100,000 On Every Hydrogen FCV Sold?"] {{Webarchive|url=https://web.archive.org/web/20150103131510/https://cleantechnica.com/2014/11/19/toyota-lose-100000-every-hydrogen-fcv-sold/ |date=2015-01-03 }}, CleanTechnica.com, November 19, 2014; and Blanco, Sebastian. [http://green.autoblog.com/2014/11/12/bibendum-2014-toyota-lose-100000-euros-fcv-hydrogen-car/ "Bibendum 2014: Former EU President says Toyota could lose 100,000 euros per hydrogen FCV sedan"] {{Webarchive|url=https://web.archive.org/web/20141124221312/http://green.autoblog.com/2014/11/12/bibendum-2014-toyota-lose-100000-euros-fcv-hydrogen-car/ |date=2014-11-24 }}, GreenAutoblog.com, November 12, 2014</ref> At the end of 2019, Toyota had sold over 10,000 Mirais.<ref>{{Cite web | url=https://global.toyota/en/company/profile/production-sales-figures/202003.html?_ga=2.211351126.219919894.1589198585-1423135873.1589198585 | title=Sales, Production, and Export Results for March 2020 | Sales, Production, and Export Results | Profile | Company | access-date=2020-05-11 | archive-date=2021-03-02 | archive-url=https://web.archive.org/web/20210302032735/https://global.toyota/en/company/profile/production-sales-figures/202003.html?_ga=2.211351126.219919894.1589198585-1423135873.1589198585 | url-status=live }}</ref><ref name=Realising>[https://www.power-technology.com/comment/standing-at-the-precipice-of-the-hydrogen-economy "Realising the hydrogen economy"],''Power Technology'', 11 October 2019</ref> Many automobile companies have introduced demonstration models in limited numbers (see [[List of fuel cell vehicles]] and [[List of hydrogen internal combustion engine vehicles]]).<ref name=Whoriskey>Whoriskey, Peter. [https://www.washingtonpost.com/wp-dyn/content/article/2009/10/16/AR2009101601002.html "The Hydrogen Car Gets Its Fuel Back"] {{Webarchive|url=https://web.archive.org/web/20170226082540/http://www.washingtonpost.com/wp-dyn/content/article/2009/10/16/AR2009101601002.html |date=2017-02-26 }}, ''Washington Post'', October 17, 2009</ref><ref>[[Riversimple]] plans to lease a vehicle to the public by 2018 [http://www.topgear.com/car-news/first-look/hydrogen-car-you-can-actually-afford "Hydrogen Car You Can Actually Afford"] {{Webarchive|url=https://web.archive.org/web/20160306210051/http://www.topgear.com/car-news/first-look/hydrogen-car-you-can-actually-afford |date=2016-03-06 }}, TopGear.com</ref>\n\nIn 2013 [[BMW]] leased hydrogen technology from [[Toyota]], and a group formed by [[Ford Motor Company]], [[Daimler AG]], and [[Nissan]] announced a collaboration on hydrogen technology development.<ref>{{cite web|url=https://www.technologyreview.com/s/510416/ford-daimler-and-nissan-commit-to-fuel-cells|title=Ford, Daimler, and Nissan Commit to Fuel Cells|first=Martin|last=LaMonica|website=technologyreview.com|access-date=15 April 2018|archive-date=9 November 2018|archive-url=https://web.archive.org/web/20181109042120/https://www.technologyreview.com/s/510416/ford-daimler-and-nissan-commit-to-fuel-cells/|url-status=live}}</ref> By 2017, however, Daimler had abandoned hydrogen vehicle development,<ref>Gordon-Bloomfield, Nikki. [https://transportevolved.com/2017/04/04/are-hydrogen-fuel-cell-cars-doomed-and-have-electric-cars-won "Are Hydrogen Fuel Cell Cars Doomed \u2013 And Have Electric Cars Won?"] {{Webarchive|url=https://web.archive.org/web/20170406022441/https://transportevolved.com/2017/04/04/are-hydrogen-fuel-cell-cars-doomed-and-have-electric-cars-won/ |date=2017-04-06 }}, TransportEvolved.com, April 4, 2017</ref> and most of the automobile companies developing hydrogen cars had switched their focus to battery electric vehicles.<ref>Williams, Keith. [https://seekingalpha.com/article/4103682-switch-hydrogen-electric-vehicles-continues-now-hyundai-makes-move "The Switch from Hydrogen to Electric Vehicles Continues, Now Hyundai Makes the Move"], ''[[Seeking Alpha]]'', September 1, 2017</ref> By 2020, all but three automobile companies had abandoned plans to manufacture hydrogen cars.<ref name=Morris>Morris, Charles. [https://cleantechnica.com/2021/10/14/why-are-3-automakers-still-hyping-hydrogen-fuel-cell-vehicles "Why Are 3 Automakers Still Hyping Hydrogen Fuel Cell Vehicles?"], CleanTechnica, October 14, 2021</ref>\n{{Clear}}\n\n A record of {{convert|207.297|mph}} was set by a prototype Ford Fusion Hydrogen 999 Fuel Cell Race Car at the Bonneville Salt Flats, in August 2007, using a large compressed oxygen tank to increase power.<ref>{{cite web |url=http://www.motorsportsjournal.com/archives/fuel_saving_vehicles_hybrids/ |title=New Hydrogen-Powered Land Speed Record from Ford |publisher=Motorsportsjournal.com |access-date=2010-12-12 |url-status=dead |archive-url=https://web.archive.org/web/20101209034212/http://www.motorsportsjournal.com/archives/fuel_saving_vehicles_hybrids/ |archive-date=2010-12-09 }}</ref> The land-speed record for a hydrogen-powered vehicle of {{convert|286.476|mph}} was set by [[Ohio State University]]'s [[Buckeye Bullet|Buckeye Bullet 2]], which achieved a "flying-mile" speed of {{convert|280.007|mph}} at the [[Bonneville Salt Flats]] in August 2008.\n\nIn 2007, the [[Hydrogen Electric Racing Federation]] was formed as a racing organization for hydrogen fuel cell-powered vehicles. The organization sponsored the Hydrogen 500, a 500-mile race.<ref>{{cite web |title=Hydrogen Electric Racing Federation looks to revolutionize motorsports |url=https://www.autoweek.com/news/a2049231/hydrogen-electric-racing-federation-looks-revolutionize-motorsports/ |website=Autoweek |access-date=17 June 2020 |date=9 January 2007 |archive-date=17 June 2020 |archive-url=https://web.archive.org/web/20200617081459/https://www.autoweek.com/news/a2049231/hydrogen-electric-racing-federation-looks-revolutionize-motorsports/ |url-status=live }}</ref>\n\n {{Main|Fuel cell bus}}\n[[File:Solaris Urbino 12 hydrogen 2.jpg|thumb|right| Solaris Urbino 12 bus near the factory In [[Bolechowo, Greater Poland Voivodeship|Bolechowo, Poland]]]]\nFuel-cell buses are being [[Fuel cell bus trial|trialed]] by several manufacturers in different locations, for example, the [[Ursus Factory|Ursus]] Lublin.<ref>{{Cite web|url=http://en.ursus.com.pl/|title=Ursus Lublin|access-date=2017-04-06|archive-date=2017-05-01|archive-url=https://web.archive.org/web/20170501214643/http://en.ursus.com.pl/|url-status=live}}</ref> [[Solaris Bus & Coach]] introduced its Urbino 12 hydrogen electric buses in 2019. Several dozen have been ordered and are expected to be delivered in 2020 and 2021.{{Update inline|date=December 2021}}<ref>[https://www.greencarcongress.com/2020/04/20200415-solaris.html "Connexxion orders 20 Solaris hydrogen buses for South Holland"] {{Webarchive|url=https://web.archive.org/web/20200626081233/https://www.greencarcongress.com/2020/04/20200415-solaris.html |date=2020-06-26 }}, Green Car Congress, 15 April 2020</ref>\n\n In March 2015, [[CSR Corporation Limited|China South Rail Corporation]] (CSR) demonstrated the world's first hydrogen fuel cell-powered tramcar at an assembly facility in Qingdao. The chief engineer of the CSR subsidiary [[CSR Sifang Co Ltd.]], Liang Jianying, said that the company is studying how to reduce the running costs of the tram.<ref>{{cite web|url=http://en.yibada.com/articles/21142/20150321/china-worlds-first-hydrogen-fueled-tram.htm#|title=China Presents the World's First Hydrogen-Fueled Tram|date=21 March 2015|access-date=6 May 2015|archive-date=6 September 2015|archive-url=https://web.archive.org/web/20150906125005/http://en.yibada.com/articles/21142/20150321/china-worlds-first-hydrogen-fueled-tram.htm|url-status=live}}</ref> Tracks for the new vehicle have been built in seven Chinese cities. China plans to spend 200 billion yuan ($32 billion) through 2020 to increase tram tracks to more than 1,200 miles.<ref>{{Cite web|url=https://www.bloomberg.com/news/articles/2015-03-25/china-s-hydrogen-powered-future-starts-in-trams-not-cars|title=China's Hydrogen-Powered Future Starts in Trams, Not Cars|date=March 25, 2015|via=www.bloomberg.com|access-date=2017-03-07|archive-date=2016-11-25|archive-url=https://web.archive.org/web/20161125010057/http://www.bloomberg.com/news/articles/2015-03-25/china-s-hydrogen-powered-future-starts-in-trams-not-cars|url-status=live}}</ref>\n\nIn northern Germany in 2018 the first fuel-cell powered [[Coradia iLint]] trains were placed into service; excess power is stored in [[Lithium-ion battery|lithium-ion batteries]].<ref>[https://www.theguardian.com/environment/2018/sep/17/germany-launches-worlds-first-hydrogen-powered-train "Germany launches world's first hydrogen-powered train"] {{Webarchive|url=https://web.archive.org/web/20180917170608/https://www.theguardian.com/environment/2018/sep/17/germany-launches-worlds-first-hydrogen-powered-train |date=2018-09-17 }}, ''The Guardian'', September 17, 2018</ref>\n\nAn experimental "Hydroflex" train, [[British Rail Class 799]], began tests in Great Britain in June 2019.<ref>{{Cite news |url=https://www.bbc.com/news/video_and_audio/headlines/48698044/hydrogen-trains-are-these-the-eco-friendly-trains-of-the-future |title=Hydrogen trains: Are these the eco-friendly trains of the future? |date=June 20, 2019 |work=BBC News |access-date=August 12, 2019 |archive-date=August 12, 2019 |archive-url=https://web.archive.org/web/20190812212642/https://www.bbc.com/news/video_and_audio/headlines/48698044/hydrogen-trains-are-these-the-eco-friendly-trains-of-the-future |url-status=live }}</ref>\n\n {{Main|Hydrogen-powered ship}}\n{{As of|2019}} Hydrogen fuel cells are not suitable for propulsion in large long-distance ships, but they are being considered as a range-extender for smaller, short-distance, low-speed electric vessels, such as ferries.<ref>{{Cite web|url=https://ship.nridigital.com/ship_mar19/could_fuel_cells_soon_be_used_in_ship_propulsion|title=Could fuel cells soon be used in ship propulsion?|date=2019-03-07|website=Ship Technology|access-date=2019-06-18|archive-date=2019-07-24|archive-url=https://web.archive.org/web/20190724190243/https://ship.nridigital.com/ship_mar19/could_fuel_cells_soon_be_used_in_ship_propulsion|url-status=live}}</ref> Hydrogen in [[ammonia]] is being considered as a long-distance fuel.<ref>{{Cite web|url=https://www.transportenvironment.org/sites/te/files/publications/2018_11_Roadmap_decarbonising_European_shipping.pdf|title=Roadmap to decarbonizing European shipping|last=Abbasov|first=Faig|date=November 2018|website=Transportenvironment.org|access-date=June 18, 2019|archive-date=June 25, 2020|archive-url=https://web.archive.org/web/20200625210807/https://www.transportenvironment.org/sites/te/files/publications/2018_11_Roadmap_decarbonising_European_shipping.pdf|url-status=live}}</ref>\n\n [[Image:Hydrogen bicycle.jpg|thumb|[[PHB (bicycle)|PHB]] hydrogen bicycle]]\nIn 2007, Pearl Hydrogen Power Source Technology Co of [[Shanghai]], China, demonstrated a [[PHB (bicycle)|PHB]] hydrogen bicycle.<ref>{{cite web|url=https://www.treehugger.com/bikes/chinese-company-plans-hydrogen-fuel-cell-bike.html|title=Chinese Company Plans Hydrogen Fuel Cell Bike|last=Fisher|first=Sean|website=[[TreeHugger]]|date=September 10, 2007|access-date=August 15, 2019|archive-date=August 19, 2019|archive-url=https://web.archive.org/web/20190819141439/https://www.treehugger.com/bikes/chinese-company-plans-hydrogen-fuel-cell-bike.html|url-status=live}}</ref><ref>{{cite web|url=https://gizmodo.com/hydrogen-fuel-cell-bike-298773|title=Hydrogen Fuel Cell Bike|website=[[Gizmodo]]|date=November 9, 2007|access-date=August 15, 2019|archive-date=August 19, 2019|archive-url=https://web.archive.org/web/20190819141432/https://gizmodo.com/hydrogen-fuel-cell-bike-298773|url-status=live}}</ref> In 2014, Australian scientists from the [[University of New South Wales]] presented their Hy-Cycle model.<ref>{{cite web|url=https://www.autoevolution.com/news/hy-cycle-is-australia-s-first-hydrogen-fuel-cell-bicycle-motorcycles-next-maybe-video-86720.html|title=Hy-Cycle Is Australia's First Hydrogen Fuel Cell Bicycle. Motorcycles Next, Maybe?|last=Tibu|first=Florin|website=autoevolution.com|date=September 18, 2014|access-date=August 15, 2019|archive-date=August 19, 2019|archive-url=https://web.archive.org/web/20190819141433/https://www.autoevolution.com/news/hy-cycle-is-australia-s-first-hydrogen-fuel-cell-bicycle-motorcycles-next-maybe-video-86720.html|url-status=live}}</ref> The same year, [[Canyon Bicycles]] sta