• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.5
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• pp.404-409
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• 2005

This study is to investigate effects of thermal conditions on sleep. Five female university students participated in the sleep experiment. Three temperature levels (22, 26, and $30^{\circ}C$) were given, and relative humidity was maintained to $50\%$. When as subject arrived in the chamber at 9 o'clock in the evening, questionnaire was given to check physical and psychological conditions. After checking conditions, subjects went to bed till 07 : 30 in the morning. Body movement was checked during sleeping. After sleep in the chamber, questionnaire was given to the subject in order to check sleep quality. Subjects evaluated sleep quality by themselves by answering the time they fall asleep and wake up, frequency of wake during sleep, causes of each waking, and feeling after sleep. Sleep quality was rated with 7-point scale. At $30^{\circ}C$ condition, body movement was significantly higher than of other thermal conditions. The best sleep quality was obtained at the $26^{\circ}C$ condition, while the worst sleep was taken at the $30^{\circ}C$ condition.

• 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 Korean Fiber Society Conference
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• 1997.10a
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• pp.364-368
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• 1997

The purpose of this Study was to determine thermal sensation and physiological responses for men in summer indoor environment, under various air temperature and relative humidity, with male university students. Subjective Evaluation, Heart Rate Variability(HRV), Electroencephalogram(EEG) were examined. We found that comfort of people was achieved at 50% R.H., 24C, and the difference of skin temperature was found at the calf area as air temperature changes. At low air temperature and low humidity, heart rate was decreased, but there was no change at brain wave, keeping a-wave.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.28 no.1
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• pp.10-15
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• 1999

산업헉명 이후 유리와 철의 이용은 넓은 개구부를 지닌 대형공간을 지닌 건축을 가능케 하였고, 1970년대 이후 새로운 건축양식의 추구라는 시대적 요구는 아트리움의 건축적 응용을 확산하게 하였다. 아트리움은 다층건물의 유리로 덮힌 대형공간으로 건물의 중심적이고 내부적인 공공의 공간이다. 대형공간으로서 아트리움의 가장 큰 특징은 넓은 채광창을 통해 실내로 유입되는 태양광에 있다. 넓은 채광창은 사람들에게 시각적인 개방감을 제공하며, 또한 많은 채광량으로 식재에 의한 조경이 가능해 외부공간과 같은 분위기를 연출하면서도 비·바람·추위 등으로부터 보호되는 쾌적한 온열환경을 제공하고 있다.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.324-329
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• 2008

Recently with the demand of well-being is increased, the demand for indoor thermal environment and air quality is increased. According to this circumstance, many people in Korea note the traditional architecture that is made by natural materials, such as a soil, stone and wood. However, few researches regarding the indoor thermal environmental characteristics of the Korean traditional houses is reported. In this study we analyzed the indoor thermal environment for Han-ok through field measurement. Moreover, based on the field measurement results. indoor thermal comfort in Han-ok is analyzed.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.970-975
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• 2008

This study considers indoor thermal comfort in an ondol space by supply vent configurations to prevent cold draft in winter. A specially-designed vent cap has been investigated in comparison with a round pan-type vent and a simple opening without a cap. Numerical simulations have been conducted using CFD to analyze thermal comfort indices such as Predicted Mean Vote (PMV) and Effective Draft Temperature (EDT) as well as air distribution index i.e. Air Diffusion Performance Index (ADPI). Results show the new vent cap provides improved thermal comfort conditions especially near ondol heated floor, as the cold outdoor air spreads upwards along the vertical wall before reaching occupant region near floor. This paper includes discussions on the flow and comfort distributions created by the thermal jets from the vents.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.2
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• pp.310-318
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• 1995

In this study, indoor thermal parameters were measured to investigate the characteristics of thermal environments and 138 occupants were questioned to evaluate Korean thermal comfort in office building in winter. Thermal sensation was estimated by using PMV(Predicted Mean Vote) and ET*(New Effective Temperature) indices. Comparing present experimental result with international standards and that of other research, Korean thermal responses were discussed. Seasonal difference between summer and winter was also discussed. It was found that TSV(Thermal Sensation Vote) is more sensitive than PMV to the variation of temperature and that the measured percentage of dissatisfied is higher than PPD(Predicted Percentage of Dissatisfied) in real office building environments. By regression analysis, the following regression equation has been obtained; TSV=0.432ET*-8.814 and neutral temperature is $20.4^{\circ}C$ in this case. Thermal comfort range based on 80% satisfaction is also $19.4{\sim}22.4^{\circ}C$.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.3
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• pp.206-217
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• 1994

In this study, indoor thermal parameters were measured to investigate the characteristics of thermal environments and 212 occupants were questioned to evaluate Korean thermal comfort in office building in summer. Thermal and comfort sensations were estimated using PMV(Predicted Mean Vote) and ET* (New Effective Temperature) which are most widely used nowadays. Comparing this experimental result with international standards and that of other research, Korean thermal responses were discussed. It was found that TSV(Thermal Sensation Vote) is more sensitive than PMV to the variation of temperature and that the measured percentage of dissatisfied is higher than PPD(Predicted Percentage of Dissatisfied) in real office building environments. By regression analysis, the following regression equation has been obtained: TSV=0.461ET*-11.808 and neutral temperature is $25.6^{\circ}C$ in this case. Thermal comfort range based on 80% satisfaction is also $24.0{\sim}26.8^{\circ}C$, which is about $1^{\circ}C$ higher than that of ANSI/ASHRAE Standard.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.97-101
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• 2009

Calculating and predicting the thermal comfort in outdoor environment are difficult than in indoor environment because composition parameters are variable, interrelations among parameters are very complex and human activities in outdoor are diverse. Moreover, the thermal expectancy of subject in outdoor environment is different from that of indoor environment. The aims of this study are to examine the difference between indoor and outdoor thermal comfort range. With this in mind, field measurement for estimating outdoor thermal environment and a questionnaire survey with simultaneous measurement around the subject were conducted.