Foreword to the Special Issue on Subjective Approaches to Thermal Perception

Comparative analysis on indoor and outdoor thermal comfort in transitional seasons and summer based on multiple databases: Lessons learnt from the outdoors

In environments with similar physical parameters, thermal comfort and sensation feelings may differ indoors and outdoors. How indoor and outdoor thermal perception differ from each other remains unclear. This study compared and discussed 29,536 field survey data, including 19,191 sets of indoor data, and 10,345 sets of outdoor data, covering five Köppen climate zones during transitional seasons and summer. Indoor data points were collected from two databases: the ASHRAE Global Thermal Comfort II and the SCATs (Smart Controls and Thermal Comfort), while outdoor data points were collected from the RUROS database (Rediscovering the Urban Realm and Open Spaces) and five individual projects executed in Singapore, Hong Kong, Guangzhou, Changsha, and Tianjin. The concepts of neutral rate (NR) and comfort rate (CR) were developed to help categorize "neutral" and "comfort" across different studies. The results of this study show that people are less sensitive to changes in thermal environment outdoors than indoors. Moreover, thermal comfort cannot be simply treated as thermal neutral, particularly for outdoor spaces. Compared with MM (mixed-mode) and NV (naturally ventilated) spaces, outdoor space does not have the highest NR, but its CR is much higher, with a wide range of SET* (Standard Effective Temperature) corresponding to CR over 80 %, from 15.5 °C to 23.4 °C. In the Cfa (humid subtropical) climate zone, significantly higher CR are recorded for outdoor spaces, although the NR are similar or even lower than those of indoors. Natural thermal resources in the outdoor thermal environment may hold the key to extending indoor comfort ranges.

Effects of Three Levels of Green Exercise, Physical and Social Environments, Personality Traits, Physical Activity, and Engagement with Nature on Emotions and Attention

The current study examined the effects of the three levels of green exercise on people’s psychological health using a randomized trial with a pretest and posttest design and further explored which variables of the physical environment (thermal comfort, noise, and air pollution), social environment (the number of companions and crowdedness), personality traits, physical activity (intensity and frequency), and engagement with nature may help explain experiences during the three levels of green exercise using a cross-sectional approach. Field studies were conducted to test the study’s hypotheses. The participants were 95 students from a technology university in Taiwan. The experiment comprised a 15-min green exercise in a park. No significant differences were found in emotions and attention between the three levels of green exercise. However, a 15-min green exercise of any level significantly improved emotions and attention. Furthermore, fatigue was significantly and negatively associated with daily transportation-related physical activity, agreeableness, and engagement with nature. Moreover, the total mood disturbance was significantly and negatively associated with engagement with nature and daily transportation-related physical activity. The degree of engagement with nature played a pivotal role in green exercise. This study provided the evidence that quantified engagement with nature is beneficial for quantified psychological health for the first time.