Identification and quantitative understanding of factors that influence occupant energy behavior and thermal state during the design phase are critical in supporting effective energy-efficient design. To achieve this, immersive virtual environments (IVEs) have recently shown potential as a tool to simulate occupant energy behaviors and collect context-dependent behavior data for buildings under design. On the other hand, prior models of occupant energy behaviors and thermal states used correlation-based approaches, which failed to capture the underlying causal interactions between the influencing factors and hence were unable to uncover the true causing factors. Therefore, in this study, the authors investigate the applicability of causal inference for identifying the causing factors of occupant/participant energy behavioral intentions and their thermal states in IVE condition and compare those results with the baseline in-situ condition. The energy behavioral intentions here are a proximal antecedent of actual energy behaviors. A set of experiments involving 72 human subjects were performed through the use of a head-mounted device (HMD) in a climate chamber. The subjects were exposed to three different step temperatures (cool, neutral, warm) under an IVE and a baseline in-situ condition. Participants' individual factors, behavioral factors, skin temperatures, virtual experience factors, thermal states (sensation, acceptability, comfort), andmore »
Impact of Outdoor Temperature Variations on Thermal State in Experiments Using Immersive Virtual Environment
Recent studies have established immersive virtual environments (IVEs) as promising tools for studying human thermal states and human–building interactions. One advantage of using immersive virtual environments is that experiments or data collection can be conducted at any time of the year. However, previous studies have confirmed the potential impact of outdoor temperature variations, such as seasonal variations on human thermal sensation. To the best of our knowledge, no study has looked into the potential impact of variations in outdoor temperatures on experiments using IVE. Thus, this study aimed to determine if different outdoor temperature conditions affected the thermal states in experiments using IVEs. Experiments were conducted using a head mounted display (HMD) in a climate chamber, and the data was analyzed under three temperature ranges. A total of seventy-two people participated in the experiments conducted in two contrasting outdoor temperature conditions, i.e., cold and warm outdoor conditions. The in situ experiments conducted in two cases, i.e., cooling in warm outdoor conditions and heating in cold outdoor conditions, were used as a baseline. The baseline in-situ experiments were then compared with the IVE experiments conducted in four cases, i.e., cooling in warm and cold outdoor conditions and heating in warm and more »
- Award ID(s):
- 1805914
- Publication Date:
- NSF-PAR ID:
- 10318622
- Journal Name:
- Sustainability
- Volume:
- 13
- Issue:
- 19
- ISSN:
- 2071-1050
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.3390/su131910638
