| Changes in the building’s indoor environment can affect psychological and physiological states and cognitive performance.Good indoor environment quality contributes to the health and efficiency of personnel.The indoor environment contains several factors such as sound,light,and temperature,but there are relatively few studies on the interaction and integrated effects of thermal and light environments in buildings,and the studies mainly are based on subjective questionnaires,lacking supports of physiological parameters.From green buildings to healthy buildings,the creation of energy-saving,comfortable,and healthy indoor environments is getting more and more attention.However,paradoxically,the energy consumption of building maintenance continues to rise on the one hand,and on the other hand,the dissatisfaction of the built environment remains high,which one of these reasons is not to take into account that the improvement of one environmental factor will also bring about simultaneous changes in other comforts.The effect of compound factors on the human body is not a simple superposition of the action of every single factor,nor can it be predicted based on the results of the action of a single factor.Therefore,it has a theoretical basis and economic prospect to study the effect of multi-environmental factors’ interaction on building users by collecting physiological parameters on this basis.In this thesis,to investigate the effects of different indoor thermal and light environments on human comfort and cognitive load adjustment,subjective questionnaires,cognitive test scores,and physiological data were collected from 26 subjects at three temperatures(24 °C,26 °C and 28 °C),three illumination levels(100 Lx,300 Lx and500Lx)and three relevant color temperatures(3000 K,4000 K,and 6500 K).The subjective questionnaire was used to assess building indoor comfort,including thermal sensation,bright sensation using building comfort questionnaire,and visual comfort,and to assess cognitive load during the cognitive task test using NASA-TLX questionnaire;the N-Back short-term memory test was used to assess cognitive ability;Heart Rate Variability(HRV)was used to reflect physiological status.The main findings are as follows:(1)There is a cross effect of indoor thermal and light environments on the perception of the built environment.Heat perception is not only influenced by the main effect of temperature,but also the illumination and related color temperature significantly affect human heat perception;bright perception is influenced by the main effect of illumination,and temperature and illumination have significant cross-effects on bright perception;visual comfort is significantly influenced by the related color temperature,and temperature and illumination changes do not affect visual comfort.(2)Heart rate variability(HRV)can be used as machine learning feature to classify subjective perceptions of human comfort effectively.Using HRV,physical environment parameters,and human body parameters as feature,the three comfort vote levels(thermal sensation vote,bright sensation vote,and visual comfort)were classified using support vector machines and decision trees after compressing the scales,and the results showed that the accuracy rate of all three classifications were more than 82%.(3)Indoor thermal and light environments significantly affect human cognitive load and cognitive ability,and there is a significant correlation between perception of the built environment,cognitive load,and cognitive ability.Although changes within the comfort temperature interval do not significantly affect cognitive load,illuminance,and associated color temperature changes affect human cognitive load.Considering the thermal-optical composite environment together,there is a cross-effect of temperature with illuminance and associated color temperature on cognitive load.Only temperature and illuminance alone would significantly affect the cognitive load of short-term memory,and there was no cross-effect of thermal and light environmental factors.(4)A structural equation model of indoor environmental quality affecting cognitive ability based on the model theory of cognitive load adjustment model was constructed.Through the empirical study,it was determined that the weight order of the influence of each dimension in the cognitive load adjustment model on the cognitive ability of shortterm memory was 0.38 for cognitive load,0.36 for built environment quality,and 0.26 for built environment perception;however,due to the complexity of the cognitive process,short-term memory cannot uniquely represent human cognitive ability,so the potential indicators of each dimension of the model need further additional research.Figure [31] Table [21] Reference [73]... |
PDF Full Text Request