case_images: PMC6260417_01
case_images: Experimental process of system overnight testing.
case_images: JHE2018-6419064.003.jpg
case_images: PMC6260417_01_JHE2018-6419064.003.jpg
case_images: fig3
case_images: In between the data collection periods, the respondents were walking freely throughout the designated area.  Figure 3 presents a diagram of the experimental process.