| The main applied method in thermal comfort evaluation is subjective questionnaires,which is reliable and convenient. However, the result of subjective evaluation be easilyinfluenced by the emotion of subjects. The physiological parameters measurement methodkept away this shortcoming, as it is objective enough. Besides, at present, the physiologicalequipment is smaller and more convenient to wear, which also gives no interruption to themain task. Therefore, applying the physiological measurements is meaningful. In thisresearch, the subjective and objective method are combined together to evaluated thethermal comfort of the subjects, and aiming at clarifying the reliability of this method, andfinding out the mechanism of thermal comfortable or thermal uncomfortable.The research is divided into two major parts: awakening and sleeping.The awakeningstate research completed in summer with an orthogonal experimental design. Theconcerned environmental factors are indoor temperature, relative humidity, fresh airflowand illuminating. In addition, the physiological parameters sensitivity under noiseenvironment was also studied. The different level for every factor are20°C,25°C,30°C;30%,50%,80%;100m~3/h,350m~3/h,600m~3/h;50lux,300lux,3000lux, respectively. Themajor utilized parameters are electrocardiogram (ECG)(heart rate [HR] and heart ratevariability [HRV]), saturation of blood oxygen (SaO2), skin resistant (SR), finger bloodflow (FBF), respiratory rate (RR) and finger pulse. The questionnaires used wereenvironment comfort evaluation and SBS investigations. The sleeping experiment wasdone in both summer and winter. The single variable in environmental factors is indoortemperature. The levels set for the summer and winter are23°C,26°C,30°C;17°C,20°C,23°C. The major utilized parameters are electroencephalography (EEG),electrocardiogram (ECG)(heart rate [HR] and heart rate variability [HRV] included),saturation of blood oxygen (SaO2), skin resistant (SR), finger blood flow (FBF) and meanskin temperature (MST), finger temperature. The questionnaires used are thermal comfort evaluation and sleep quality investigation. The physiological measurement lasts the wholeexperiment procedure and the subjective investigations were done after that.The results show that:(1) different physiological parameters can be used to evaluatedifferent environmental parameters. Such as, HRV, FBF and RR can be combined toevaluate acoustical environment, HRV and SaO2is suitable for thermal environment, RRcan be chosen for fresh air volume changing environment, FBF and SC can be selectedaltogether to judge lighting environment.(2) Different physiological parameters can beused to evaluate the thermal comfort and thermal sensations respectively, such as HRV, HRand RR can evaluate thermal comfort, SaO2, SC and FBF can evaluate thermal sensation.(3) The most comfortable environment at wake is: temperature-25°C, relativehumidity-50%,fresh air-600m~3/h,illuminating-3000lux。The most comfortable sleepingenvironment is23°C(winter),26°C(summer), which has a most satisfied sleep quality,highest power of-wave,shortest sleep latency and longest slow eave sleep. The spectrumanalysis of EEG frequencies is reliable.(4) The method of using subjective and objectivemethods to evaluate sleeping comfort is scientific and reliable. EEG is the most sensitiveparameter to judge the sleeping condition, and the HR, HRV and RR can be used as theassistant index. Parameters of SaO2, FBF and MST are relating to the levels of sleepenvironment temperatures. That is accordance with awakening.(5) Moreover, there aregender differences exist in sleeping quality and sleeping comfort temperature preference.The female is more sensitive to cool environment, and the male is more intolerence withwarm temperature. The preferable ambient temperature for female is higher than the male.All can be due to the measured physiological features difference of measn skin temperature,blood flow and finger temperature.(6) The most comfortable temperature for awakeningsubjects is lower than for the sleeping ones. Meanwhile, the thermal sensation for the sametemperatures before sleeping is cooler compared with that after awakening, which is due tothe body temperature changing through the sleeping process.(7) The themal sensation afterawakening lowers more significant in summer than in winter, which is caused by biggermean skin temperature dropping during sleeping in summer.
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