• Ecology and Resilient Infrastructure
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• v.5 no.4
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• pp.219-228
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• 2018

This study measured the Physiological Equivalent Temperature (PET) of the hottest day time in a day, in order to verify the characteristics of human thermal comfort in case of heat wave during summer time in each region, by subdividing the urban areas in accordance with the climatic characteristics with the use of Local Climate Zone (LCZ) as a method of classifying the type of urban climate and the land cover map, targeting the Homaesil residential development district in Suwon. In the results of measurement, the forest and paddy field showed the moderate heat stress while the urban park showed the strong heat stress. Other developed areas showed the extreme heat stress. Such results show the possibility of institutional utilization for the improvement of human thermal comfort through the verification of climatic characteristics and differences in each type of urban areas, and the efficient placement of green infrastructure and the planning of land use to cope with the heat wave even in the planning stage for the establishment of urban planning.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.1
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• pp.47-59
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• 2023

Due to climate change and urbanization, abnormally high temperatures and heat waves are expected to increase in urban and deteriorate thermal comfort. Planting of street trees and changing the albedo of urban surfaces are the strategies for mitigating the thermal environment of urban, and both of these strategies affect the exposure and blocking of radiative fluxes to pedestrians. After measuring the shortwave and longwave radiation according to the ground surface with different albedo and the presence of street trees using the CNR4 net radiometer, this study analyzed the relationship between this two strategies in terms of thermal environment mitigation by calculating the MRT(Mean Radiant Temperature) of each environment. As a result of comparing the difference between the downward shortwave radiation measured under the right tree and at the control, the shortwave radiation blocking effect of the tree increased as the downward shortwave radiation increased. During daytime hours (from 11 am to 3 pm), the MRT difference caused by the albedo difference(The albedo of the surfaces are 0.479 and 0.131, respectively.) on surfaces with no tree is approximately 3.58℃. When tree is present, the MRT difference caused by the albedo difference is approximately 0.49℃. In addition, in the case of the light-colored ground surface with high albedo, the surface temperature was low and the range of temperature change was lower than the surrounding surface with low albedo. This result shows that the urban thermal environment can be midigate through the planting of street trees, and that the ground surface with high albedo can be considered for short pedestrians. These results can be utilized in planning street and open space in urban by choosing surfaces with high albedo along with the shading effect of vegetation, considering the use by various users.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.107-117
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• 2024

This study investigated temporal changes in forest physical variables and their effects on thermal comfort and physiological and psychological responses. Environmental factors (air temperature, mean radiant temperature, wind speed, and relative humidity), the predicted mean vote (PMV), and the predicted percentage of dissatisfied (PPD) visitors were continuously measured between 9:00 AM and 6:00 PM. We assessed the physiological and psychological responses (heart rate variability, heart rate, oral temperature, blood pressure, pulse rate, thermal sensation vote, comfort sensation vote, and subjective feelings) of 30 male university students (average age: 21.7±1.9 years), who closed their eyes and relaxed for 5 minutes every hour. Examination of correlations between environmental factors and physiological responses showed that ① the mean radiant temperature, wind speed, and relative humidity significantly changed with time; ② PMV and PPD also showed significant changes over time, and the thermal sensation vote corresponded with PMV; however, the comfort sensation vote did not correspond with PPD; ③ Among the physiological responses, parasympathetic nerve activity, sympathetic nerve activity, heart rate, and diastolic blood pressure significantly varied with time, with parasympathetic nerve activity having the lowest value and sympathetic nerve activity the highest at the highest air temperature (2:00-4:00 PM); and ④ Air temperature, mean radiant temperature, and wind speed showed a negative correlation with parasympathetic nerve activity and a positive correlation with sympathetic nerve activity. These findings indicate that the relaxation effects of the forest environment depend on what time of day people are exposed to it, and the changes occurring in forest environmental factors over time modulate these effects.

• Proceedings of the SAREK Conference
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• 2006.11a
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• pp.62-62
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• 2006

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.47-47
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• 2004

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.140-140
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• 2005

• Science of Emotion and Sensibility
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• v.3 no.2
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• pp.1-8
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• 2000

본 연구에서는 기존의 공조방식 및 본 연구에 제안된 개별환경제어시스템(PEM)으로부터 재실자가 거주하여 사용하고 있는 컴퓨터룸(CR)에 대해 기하학적으로 3차원 시뮬레이션을 수행하여 CR의 열취득과 재실자 온열 쾌적감을 감성공학적 측면에서 분석하였다. 본 연구로부터 바닥으로부터 공기를 유입하여 천정으로 유출하는 바닥취출공조(TAM)방식이 실내 환경 개선에 유리하고 디퓨저만을 통하여 공기가 유입되어 천정과 바닥으로 공가가 유출되는 개별공조(PEM) 방식은 열적 냉각 성능은 좋으나 컴퓨터와 재실자 주변에 강력한 ㅐ순환 유동을 유인하여 실내 환경의 쾌적감 측면에서는 불리하다. 그러나 PEM과 TAM방식의 결합이 감성공학적 온열특성 분포로부터 CR의 재실자 주변온도 분포에 최적임을 알 수 있다.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.463-468
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• 2005

An experimental study on the optimal control algorithm for central heating system for minimizing energy consumption while maintaining the comfort of indoor thermal en vironment in terms of the environmental variables such as loads and weather. experimental study has been done by one using the prototype of central heating system. As a result the optimal control algorithm shows good energy performance in comparison with conventional control one.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.32-32
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• 2007

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.111-111
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• 2004