Thermal comfort (TC) – how comfortable or satisfied a per- son is with the temperature of her/his surroundings – is one of the key factors influencing the indoor environmental quality of schools, libraries, and offices. We conducted an experiment to explore how TC can impact students’ learning. University students (n = 25) were randomly assigned to different temperature conditions in an office environment (25◦C → 30◦C, or 30◦C → 25◦C) that were implemented using a combination of heaters and air conditioners over a 1.25 hour session. The task of the participants was to learn from tutorial videos on three different topics, and a test was given after each tutorial. The results suggest that (1) changing the room temperature by a few degrees Celsius can stat. sig. impact students’ self-reported TC; (2) the relationship between TC and learning exhibited an inverted U-curve, i.e., should be neither too uncomfortable nor too comfortable. We also explored different computer vision and sensor-based approaches to measure students’ thermal comfort automatically. We found that (3) TC can be predicted automatically either from the room temperature or from an infra-red (IR) camera of the face; however, (4) TC prediction from a normal (visible-light) web camera is highly challenging, and only limited predictive power was found in the facial expression features to predict thermal comfort.
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Low-Energy Wearable Cooling Strategy for Thermal Comfort at a Warm Environment
The objective of this study is to assess the effectiveness of wearable cooling in improving thermal comfort for a warm environment that would become prevalent due to more frequent extreme weather events, especially when air conditioning is not accessible for many developing countries. The experiment was conducted in an environment room with air temperature maintained at 31 °C and relative humidity at 55%. The study tested 30 participants using a wearable cooling device at the upper back location, while another 30 had no local cooling as the control group. Participants’ thermal comfort, thermal sensation and other metrics were assessed three times for a test session. The clothing insulation was 0.36 clo to simulate summer attire. The results showed significantly lower average local and whole-body thermal sensation for the participants with the wearable cooling device than the control group by considering all the votes during the entire session. Compared to the baseline, in particular, the local cooling group indicated a significant reduction in local thermal sensation for all three times of self-evaluation. Nevertheless, the reduction in overall thermal sensation occurred right after the local cooling was applied. Such a significant reduction was not observed after a while and then emerged again during the test, indicating an interactive phenomenon involving thermal adaptation and comfort restoration which will be investigated in the future.
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- Award ID(s):
- 1931077
- NSF-PAR ID:
- 10374220
- Date Published:
- Journal Name:
- The 5th International Conference on Building Energy & Environment (COBEE)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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