• 설비공학논문집
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• 제20권11호
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• pp.711-717
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• 2008

Despite the fact that UFAD(Under Floor Air Distribution) systems have many benefits and are being applied in the field in increasing numbers, there is a strong need for an improved fundamental understanding of several key performance features of these systems. This study numerically investigates the effect of supplied air temperature and supplied flow rate on the performance of UFAD, especially focused on thermal comfort. Also this study has compared UFAD with conventional overhead air distribution system. In contrast to the well-mixed room air conditions of the conventional overheat system, UFAD system produces an overall floor-to-ceiling airflow pattern that takes advantage of the natural buoyancy produced by heat sources in the occupied zone and more efficiently removes heat loads and contaminants from the space. Thermal comfort parameters were evaluated by CFD approach and then PMV was computed to detect the occupants' thermal sensation. Results show that radiative mean temperature plays crucial role on the evaluating PMV. Until now, the radiative temperature has been the missing link between CFD and thermal comfort, but the present study paves the way for overcoming this weakness.

• 한국의류학회지
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• 제37권8호
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• pp.1095-1106
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• 2013

This study evaluated the wear comfort properties of water-vapor-permeable (WVP) garments using a movable sweating thermal manikin. Manikin tests were performed in a climatic chamber (temperature T=20, $35{\pm}0.5^{\circ}C$ and relative humidity $H=50{\pm}10%$) using seven sportswear outfits (a long sleeve shirts and a long pants) made with seven different WVP fabrics. Physiological responses of wear trials could be correlated with measurement parameters of the thermal manikin experiment; subsequently, a regression model that represented a final comfort sensation could be obtained. The regression model developed in this work is based on thermal manikin measurements; consequently, it provides an independent comfort sensation level in a relatively short time at a low cost while maintaining the reproducibility of results. It translates into more actual choices for sportswear manufacturers and sportswear consumers.

• KIEAE Journal
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• 제7권5호
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• pp.59-64
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• 2007

Using air conditioner has been increased in home or office buildings in summer. Also various problems related to air conditioning such as disease induction happened by using air conditioner excessively and operating long. Active operation control is needed for occupant's health when air conditioner operates long. We should think ahead to acquire thermal comfort of occupants which represents psychological and physiological reaction for this operation. Research has been progressed to observe activity of autonomic nervous system by trying to quantitate change of thermal comfort. In this study, questions of the subject and change of body's autonomic nervous system were chosen to evaluate thermal comfort during operation of air conditioner for a long time. Electrocardiogram and questions of the subject which is the progress of changing TSV and CSV by occupants indoor were measured when room air conditioner is operated for a long time, and an air-conditioned adaptability of human body was evaluated by acquiring the change rate of autonomic nervous system through analyzing HRV. As a result of the evaluation, change rate of body's autonomic nervous system corresponded to votes of the subject's question generally, but was distinguished from analysis result of warm-cold sensation in a low temperature area.

• 한국수소및신에너지학회논문집
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• 제26권6호
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• pp.645-651
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• 2015

Numerical study on human thermal comfort in a low floor bus has been conducted. Human thermal comfort in a bus depends mainly on air temperature, air velocity, mean radiant temperature, humidity, and direct solar flux, as well as the level of activity and thermal properties of clothing. The paper presents the velocity and temperature distribution, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) indices for the driver and passengers.

• 한국주거학회논문집
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• 제14권3호
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• pp.1-8
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• 2003

It is not sufficient to control the indoor thermal environment using only one or two parameters by itself as human response for the control of indoor thermal environment. So a proper environmental thermal index is required for the control of indoor thermal environment effectively. In this study, the physical environment was measured and analysed and the skin temperature of the subjects and their response were investigated to evaluate the optimum thermal comfort range for cooling season in an apartment house. As a result, the optimal temperature was 26.1$^{\circ}C$ and the temperature ranges which more than 80% responded as satisfactory were 24.1~28.$0^{\circ}C$, respectively. As the OT had most significant interrelation with the PMV, it is desirable to use the OT in evaluating the thermal environment during cooling. Also, the comfort range was concluded between OT 25.5~27.3$^{\circ}C$ by appointing the PMV of -0.5~0.5 as the optimum comfort condition. In addition, the Human responses were compared with calculated PMV, OT and MRT and the relationships are suggested in order to utilize to control indoor thermal environment.

• 토지주택연구
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• 제1권1호
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• pp.19-25
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• 2010

최근 에너지 절약을 화두로 건물에서의 에너지 절약기술들이 크게 요구되어 지는 반면 재실자의 온열쾌적환경은 비교적 비중 있게 다루어지지 않고 있다. 실내공간의 쾌적성은 재실자의 만족감과 더불어 생산성을 향상시키는 등의 역할을 하며, 최근 삶의 질 향상 등에 따라 그 필요성이 크게 요구되고 있는 실정이다. 따라서 본 연구에서는 공동주택을 대상으로 겨울철 난방 시 쾌적지표를 통한 실내 온열환경 제어의 타당성을 검토하고자 시뮬레이션을 수행하였으며, 주거건물에서의 일상적인 실내온도와 에너지 절약 설계기준에서 제시한 실내 설정온도, 그리고 쾌적지표를 설정으로 한 각 제어조건의 온열환경과 에너지 소비량을 비교 분석 및 검토하였다. 본 연구결과에 따르면, 쾌적지표인 PMV로 실내환경을 제어했을 때 에너지 절약설계 기준인 $22^{\circ}C$로 실내온도를 설정하였을 때보다 에너지 소비량은 29% 증가하지만 주거용 건물에서 일반적으로 유지되는 실내온도인 $24^{\circ}C$ 보다는 에너지소비량은 11% 정도 감소하며, 온열쾌적감도 각 제어조건 중 가장 우수하게 나타났다. 따라서 여러 가지 제어변수들을 통한 연구가 지속된다면 주거용 건물에서도 쾌적지표를 활용한 실내 공간의 제어방법은 건물의 에너지를 절약하고 실내 환경의 쾌적성을 증대시키는 주요기술이 될 수 있을 것으로 기대된다.

• 전기전자학회논문지
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• 제19권4호
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• pp.603-609
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• 2015

열 쾌적 제어는 실내 환경의 질을 나타내는 기본 요소로써 건물에서 사용되는 에너지와 거주자의 만족도에 매우 밀접하게 연관되어 있다. 본 논문에서는 실내의 쾌적 상태(Predictive Mean Vote)를 검출하고, 목표 소비 전력 내에서 냉난방 온도, 습도, 풍량을 제어함으로써 에너지를 절감하고 근무자에게 쾌적한 환경을 제공할 수 있는 스마트 쾌적 제어 알고리즘을 제안하였다. 시뮬레이션 결과, 열 쾌적 제어에 의한 냉난방제어는 기존의 일반 냉난방기에 비해서 실내의 쾌적도는 그대로 유지한 상태에서 0.5kW의 전력을 절감할 수 있고, 조명제어 알고리즘이 적용된 조명 제어에 의해서 49.2%의 조명 개선 효과가 이루어짐을 알 수 있었다. 시뮬레이션을 통해서 검증된 쾌적 제어 알고리즘을 기존의 냉난방기에 적용할 경우 쾌적도는 유지하고 에너지는 절감할 수 있을 것으로 예상된다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.311-317
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• 2008

As outdoor environment become worse due to concentration of population in large cities, the importance of environmental control strategies such as the arrangement of green space or water space and ventilation paths, has been increasingly recognized. However, most of the studies focus on the assessment on outdoor thermal environment, few studies focus on the interrelationship between thermal environment in residential block and human thermal comfort. The aims of this study is to develop the outdoor planning method to reduce the heating/cooling load in an apartment unit or entire block by the sustainable approaches in outdoor environmental design. In this paper, on the basis of the prior studies, the effect of the outdoor thermal environment on human thermal comfort will be analysed.

• 한국지열·수열에너지학회논문집
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• 제11권1호
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• pp.7-14
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• 2015

This study has been purposed to provide thermal comfort range in accordance with the residential style of radiant floor heating space, and to compare it with the thermal comfort range at predicted mean vote. The survey for the thermal sensation vote to the subjects and the measurement of environmental factors has been executed, and regression analysis has been performed. It is interpreted that the combination of the physical factor and the psychological factor results lower neutral point of the floor sitting style than that of the chair sitting style. There are some difference between the measured predicted mean vote and the thermal sensation vote via survey, which appears to be caused by distinctive heat transfer characteristic of floor radiant heating space, such as, high radiant temperature and contact thermal sensation of floor surface.

• KIEAE Journal
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• 제16권1호
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• pp.11-19
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• 2016

Purpose: PMV, PET, and similar thermal comfort indices and microclimate modeling have recently become actively used to evaluate thermal comfort. This study will look at pedestrian roads with diverse spatial characteristics on university campus using the ENVI-met model as the base for onsite measurement. Method: The PET was used as the thermal comfort index. The first microclimate measures were collected on September 20, 2014, and the second microclimate measures were collected on June 1, 2015. The ENVI-met model was used at the same time. Result: As a results, Onsite measurement results differed depending on the PET spatial characteristics. The location associated with the most discomfort had a PET of $47.8^{\circ}C$. The spatial characteristics of this place included a with no shade. The most comfortable location had shade, and the PET was $24.6^{\circ}C$. When the ENVI-met model and onsite measurements were compared, similar patterns were found, but with a few differences at specific points; this was due to the limitation of using input materials such as trees, buildings, and covering materials with the ENVI-met model. This factor must be thoroughly considered when analyzing modeling results.