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Abstract Thermal perception entails to a certain extent visual aspects, which are taken into account when subjects are requested to express their thermal votes to a given indoor or outdoor space. This study concentrates on human cognition and preconceptions of thermal behavior from projected 360° imagery. Urban scenes have been shown with the concurrent administration of thermal perception questionnaires to two distinct sample groups: 1) volunteer participants (n = 86) who filled out online responses to questions regarding thermal perception in undisclosed locations; 2) undergraduate students (n = 85) under temperature-controlled conditions in a computer lab. Both groups have evaluated three different 360° urban scenes with varying morphology attributes using the provided web link to the 360° VR platform Roundme. Method of analysis included means, medians, statistical significance (p-value) and percentage graphs of perceived thermal sensation. Despite the absence of any information regarding location, season and time of day of the scenes, both groups expressed different perceptions with respect to the estimated thermal conditions and thermal comfort levels for the observed urban scenes, consistently attributing windier and warmer thermal conditions to an urban square location and less so to a street canyon. Graphical abstract Unlabelled Image Highlights • A similar trend in thermal perception was obtained for databases with remarkable differences. • Different protocols and samples suggest there is a context-related effect on thermal perception. • The outlook of a given outdoor space affects the way we perceive it thermally. [ABSTRACT FROM AUTHOR]

Interactions between human beings and the built environment are mediated by physiological and psychological stimuli, which may interfere in the perception and satisfaction related to indoor comfort variables. The study aims to explore the relationship between daylighting features and possible impacts on humans in regards to lighting preferences. The influence of different daylighting configurations, glazed façade orientation and season of the year on lighting preferences in human beings was evaluated by means of tests in a rotating climate with monitoring of environmental variables, developed by the Karlsruhe Institute of Technology, Karlsruhe, Germany. The sample, n = 16, is composed of German male students (height SD = 1.80 m, SD = 0.06; body weight SD = 80 kg, SD = 8.9; and age SD = 24.9 years, SD = 3.6). Under controlled thermal conditions (PMV approx. ±0.5), participants remained in two office-like environments over 5 h (8:00 am to 1:00 pm - local time) three days in a row, for three seasons of the year, totaling nine days of data collection per participant. Definitions of glazed façade orientations for the experimental rounds were done by means of computer simulations. Objective variables were measured by spectroradiometers at desk height, with sensor h = ca. 0.90 m, and comfortmeters. Preferences of daylighting features was assessed by a questionnaire with Likert-scale alternatives, administered online at 8:50 am, 10:30 am and 12:30 pm. Objective and subjective data were analyzed statistically (Spearman's rho, rs), suggesting possible correlations between lighting preferences and objective variables, including: E (lx), CCT (K), DWl (nm) and the circadian metric a cv (circadian action factor). [ABSTRACT FROM AUTHOR]

This study investigates the joint effect of atmospheric conditions and urban morphology, expressed as the Sky View Factor (SVF), on intra-urban variability. The study has been carried out in Glasgow, UK, a shrinking city with a maritime temperate climate type, and findings could guide future climate adaptation plans in terms of morphology and services provided by the municipality to overcome thermal discomfort in outdoor settings. In this case, SVF has been used as an indicator of urban morphology. The modified Pasquill-Gifford-Turner (PGT) classification system was adopted for classifying the temperature monitoring periods according to atmospheric stability conditions. Thirty two locations were selected on the basis of SVF with a wide variety of urban shapes (narrow streets, neighbourhood green spaces, urban parks, street canyons and public squares) and compared to a reference weather station during a total of twenty three transects during late spring and summer in 2013. Maximum daytime intra-urban temperature differences were found to be strongly correlated with atmospheric stability classes. Furthermore, differences in air temperature are noticeable in urban canyons, with a direct correlation to the site's SVF (or sky openness) and with an inverse trend under open-air conditions. [ABSTRACT FROM AUTHOR]

We investigate acclimatization effects on outdoor thermal perception. Steady-state conditions were ensured by a prolonged stay of participants (N = 16) in a test chamber prior to the subjects' exposure to outdoors, i.e. after five consecutive hours under thermal comfort conditions indoors. After that, subjects walked in a controlled pace around the external precincts of the facility and were asked to vote on their thermal sensation and preference according to a standard questionnaire: a) immediately, b) 15 min and c) 30 min after they left the controlled indoor environment. Altogether 36 sessions were performed with varying outdoor conditions over winter, spring, and summer 2015. We evaluate acclimatization effects on the subjects' thermal perception against predictions of the outdoor thermal conditions in terms of UTCI (Universal Thermal Climate Index) and the derived DTS (Dynamic Thermal Sensation). ANOVA results showed that UTCI conditions remained unchanged throughout the 30-min exposure time outdoors, but differed between seasons, whereas the subjects' thermal perception votes differed both between seasons and the times of votes. Reduced thermal sensitivity was noticed in winter and spring at the first vote, resulting in greater prediction bias (underestimation), which was attenuated at higher temperatures and during longer exposure times. An initial overshooting at the first vote towards cool response occurred at moderate temperatures in summer, increasing bias (overestimation), which was also attenuated with increasing temperature and time of exposure. Acclimatization to a heatwave in summer lead to enhanced heat tolerance just after it, with acclimatization loss in the subsequent session. [ABSTRACT FROM AUTHOR]

The thermal performance of a vegetated roof system was tested for a lightweight, fiberglass security booth during a spring-summer period in subtropical Curitiba, Brazil. An experimental and a control booth, commercially available and widely used in Brazil, were compared for three roof configurations (only substrate; substrate and vegetation; substrate, vegetation and shading mesh) and for two window conditions (shaded and unshaded). Comfort and thermal stress analyses followed normative parameters of wet-bulb globe temperature (WBGT) and effective temperature (ET). The non-insulated lightweight enclosure reduced advantageous effects from thermal stabilization of indoor air temperatures with the addition of the green roof. Benefits were otherwise observed in ceiling surface temperatures, which reached a peak reduction of 12 K at the experimental booth relative to the control booth. Infra-red images further confirmed spot measurements of surface temperatures in both booths. [ABSTRACT FROM AUTHOR]