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The relation between the thermal sensation and the thermoreceptors temperature under steady-state conditions.
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![Figure 3. Comparison of experimental data of Arens et al. [15] and...](profile/Alireza-Zolfaghari-4/publication/241179869/figure/fig3/AS:668981270704128@1536508972001/Comparison-of-experimental-data-of-Arens-et-al-15-and-simulated-results-of-the-present_Q320.jpg)
![Figure 5. Comparison of measured thermal sensation of Goto et al. [16]...](profile/Alireza-Zolfaghari-4/publication/241179869/figure/fig5/AS:668981270695938@1536508972069/Comparison-of-measured-thermal-sensation-of-Goto-et-al-16-and-simulated-results-of-the_Q320.jpg)
So far, all of the thermal sensation models have been developed on the basis of energy balance equations for each compartment of the human body. But, the human body feels thermal environment by response of cutaneous thermoreceptors, not by balance of energy. Therefore, the mentioned models are not in conformity with the physiology of thermal sensat...
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Context 1
... the present study, the thermoreceptors temperature and the thermal sensation index are calculated by using the STB model and Eq. (3). Fig. 2 illustrates the relation between the thermal sensation and the thermoreceptors temperature under steady-state conditions. These data are specified in an applicable range, i.e., 5 ºC < T a < 40 ºC; 0 < V a < 0.8 m/s; 25% < RH < 75%; 0 < I cl < 1.5 clo; 0.7 met < M act < 1.5 met. As shown in Fig. 2, there is an almost linear relation ...
Context 2
... are calculated by using the STB model and Eq. (3). Fig. 2 illustrates the relation between the thermal sensation and the thermoreceptors temperature under steady-state conditions. These data are specified in an applicable range, i.e., 5 ºC < T a < 40 ºC; 0 < V a < 0.8 m/s; 25% < RH < 75%; 0 < I cl < 1.5 clo; 0.7 met < M act < 1.5 met. As shown in Fig. 2, there is an almost linear relation between the thermal sensation and the temperature of cutaneous thermoreceptors. However, the lines of warm and cold conditions do not have a similar slope. In other words, the warm thermal sensation is more sensitive to the temperature change of thermoreceptors than the cold thermal sensation. ...
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Citations
... Compared to other methods, PCS shows irreplaceable characters that enable people to meet their various personalized thermal needs, even without the shelter of building envelopes or conventional HVAC systems. Furthermore, different regions of the human body contribute differently to thermal comfort [25], [26] and there are physiological interactions between the body parts, for example, when one region of the body cools down, it triggers reflex vasoconstriction in other sections [27]. Therefore, research exploring simultaneous thermal stimulus across human body is more expected rather than measuring thermal reactions on an isolated zone. ...
In this paper, we investigate the feasibility, robustness and optimization of introducing personal comfort systems (PCS), apparatuses that promises in energy saving and comfort improvement, into a broader range of environments. We report a series of laboratory experiments systematically examining the effect of personalized heating in neutralizing individual, spatial and temporal variations of thermal demands. The experiments were conducted in an artificial climate chamber at -15 degC in order to simulate extreme cold environments. We developed a heating garment with 20 pieces of 20 * 20 cm2 heating cloth (grouped into 9 regions) comprehensively covering human body. Surface temperatures of the garment can be controlled independently, quickly (within 20 seconds), precisely (within 1 degC) and easily (through a tablet) up to 45 degC. Participants were instructed to adjust surface temperatures of each segment to their preferences, with their physiological, psychological and adjustment data collected. We found that active heating could significantly and stably improve thermal satisfaction, the overall TSV and TCV had been improved 1.50 and 1.53 during the self-adjustment phase. Preferred heating surface temperatures for different segments varied widely. Further, even for the same segment, individual differences among participants were considerable. Such variances were observed through local heating powers, while unnoticeable among thermal perception votes. In other words, all these various differences could be neutralized given the flexibility in personalized adjustments. Our research reaffirms the paradigm of "adaptive thermal comfort" and will promote innovations on human-centric design for more efficient PCSs.
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In Genesis, the first book of the Bible, the fall of man is recorded and the consequence of labour and death is pronounced. The insights into the facility for brain cooling from eighteenth and nineteenth century commentators is remarkable:
