• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.7
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• pp.669-680
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• 2005

The purpose of this study is to develop the air-conditioning unit combined with the lighting unit for workspace and to supply its performance data at architectural design stage. The air-conditioning unit is one of the components of a workspace integrated unit, which can be defined as the planning unit satisfying the environmental comfort criteria of workspace. Air-conditioning diffusers are classified according to throws and features by literature review and case study. Then diffusers are combined with the lighting unit. Through the CFD simulation, the thermal performance of each unit was evaluated and finally various air-conditioning units combined with the lighting units were developed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.6
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• pp.543-550
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• 2003

In order to saving the energy for HVAC system of buildings, utilization of wind-induced cross ventilation is thought to be promising. However, utilization of natural ventilation alone is not sufficient for maintaining the human thermal-comfort such as in hot and humid regions. A hybrid air conditioning system with a controlled natural ventilation system, or combination of natural ventilation with mechanical air conditioning is thought to overcome the deficiency of wind-driven cross ventilation and to have significant effects on energy reduction. This paper describes a concept of hybrid system and propose a new type of hybrid system using radiational cooling with wind-induced cross ventilation. Moreover, a radiational cooling system is compared with an all-air cooling system. The characteristics of the indoor environment will be examined through CFD (Computational Fluid Dynamics) simulation, which is coupled with a radiation heat transfer simulation and with HVAC control in which the PMV value for the human model in the center of the room is controlled to attain the target value.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.05a
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• pp.104-108
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• 2001

복사에 의한 냉난방은, 장시간 재실하는 방이나 소음, 기류에 민감한 장소에 적합하고 에너지 절약면에서도 유효한 냉난방 방식이라고 알려져 있다. 일반적으로 널리 알려져 있는 바닥난방은 실온의 수직분포가 균일함으로서 인체에 쾌적한 난방방식으로 알려져 있다. 이것에 비해, 바닥의외의 벽, 천장을 활용한 냉난방설비의 쾌적성에 대해서는 아직 충분히 검토되고 잇지 않다. 따라서 본 연구는 물순환식 복사 냉난방장치를 이용하여 겨울철의 천장복사난방이 인체에 미치는 생리적, 심리적영향을 밝히고 복사난방의 유용성에 대해서 검토하는 것을 목적으로 한다. 실험은 일본 나라여자대학 인공기후실을 이용하였고, 실험조건은 실온 18$^{\circ}C$, 21$^{\circ}C$, 24$^{\circ}C$ 천장온도 $25^{\circ}C$, 3$0^{\circ}C$, 35$^{\circ}C$의 조건을 조합하여 7조건으로 설정하였다. 또, 상대 습도 40%, 기류속도 0.1m/s 이하로 일정하게 유지시켰다. 생리적반응으로는 피부온14점과 직장온을 30초 간격으로 측정하였고, 혈압, 심박수, 체중, 체지방율을 측정하고 심리적반응으로는 온열감, 쾌적감등의 항목을 10분간격으로 측정하였다.

• Journal of the Korean Society of Visualization
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• v.8 no.2
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• pp.40-44
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• 2010

Thermal comfort inside a passenger car has been receiving large attention in automobile industries. Especially, the performance of windshield defroster is important in the design of a car to ensure passenger comport and safety. Thereby, better understanding on the ventilation flow along the vehicle windshield is essential to evaluate the performance of windshield defroster. However, most previous studies dealt with the defrost flow using CFD (computational fluid dynamics) calculations or scale-down model experiments. In this study, a real commercial automobile was used to investigate the flow discharged from the vehicle defroster and the ventilation flow along the windshield using a PIV velocity field measurement technique. The experimental data would be useful to understand the flow characteristics in detail and also can be used to validate numerical predictions.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.164-168
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• 2001

의복착용시의 쾌적성은 의복의 보온력 조절에 의해 의복내 기후를 형성하여, 체온을 일정하게 유지하게 하는 역할을 하므로 건강과 직접적인 관련이 있다. 그러므로 건강이나 쾌적성 평가의 측면에서 의복내기후가 체계적으로 파악되어야 한다. 따라서 본 연구에서는 사무실 환경에서 의복착용시 착용실험을 실시하여 계절적인 의복내기후의 변동을 살펴보았다. 그 결과 겨울 31.8$^{\circ}C$, 48.6%, 봄 33.5$^{\circ}C$, 47.9%, 여름 32.7$^{\circ}C$, 64.6%, 가을 31.9$^{\circ}C$, 43.6%인 것으로 나타났다. 또한 계절간의 차이는 의복내온도에 있어서 가을과 겨울간에는 차이가 없었으며, 봄과 여름간에는 차이가 있었다. 의복내습도는 여름과 겨울간에는 차이가 없었으며, 다른 계절간에는 차이가 뚜렷하였다.

• Journal of Fashion Business
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• v.3 no.1
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• pp.125-137
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• 1999

The present study aims to reveal the sweating reaction of male adults, focused on athletes. With six subjects (3 athletes and 3 non-athletes) in two different conditions of ambient temperature (I : $25\pm1.0^{\circ}C$, II : $29.5\pm1.0^{\circ}C$), their total sweat rate, local sweat rate, skin temperature, physiological reaction (rectal temperature, blood pressure, and pulse rate), and psychological reaction (thermal, moisture, comfort, and perceptive sweat sensations) were measured. The comparison gave the following results: Total sweating rate was greater in non-athletes, while the two groups had more perspiration in ambience II. Local sweating rate in both ambiences was the greatest in the central breast area (athletes) and the infrascapular area (non-athletes). The mean skin temperature had more changes of increase and decrease in athletes. As to physiological reaction, non-athletes had lower rectal temperature and blood pressure as well as higher pulse rate. As for psychological reaction in Ambience II, the 4 sensations were mostly 'hot', 'humid', 'uncomfortable', and 'sweaty'.

• Journal of the Korean housing association
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• v.11 no.4
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• pp.77-84
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• 2000

The purpose of this paper is to find a visible project area for an average six year old Korean child in radiant enclosures having standing pose. The results using this method will be necessary to find effective radiation area, effective radiation area factor, form factor, and mean radiant temperature for an average six years old Korean child consists of 3012 triangles. The methods to find visible project area of an average six years old Korean at arbitrary view point will be presented. The visible project area for Korean child is needed for evaluating thermal comfort for six years old Korean child. The biggest visible project area of an average six years old Korean is $\textrm{cm}^2$$2.061.0\textrm{cm}^2$ at the view point of alfa 0.0 degree and beta 0.0 degree, and the smallest visible real area of an average six years old Korean is $567.1\textrm{cm}^2$ at the view point of alfa 15.0 degree and beta 90.0 degree.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.327-334
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• 1998

The oil crisis of the 1970s and the rise in oil prices motivated people to implement energy conservation strategies. Buildings were fitted with additional Insulation and reduced ventilation rates. The reduction of mechanical and natural ventilation rate led to Increases In Indoor pollutant concentrations which result- ed In Increased health risks from Indoor exposure to pollutants. The variable-air-volume /bypass fitration system/VAV/BPFS) is a variation of the conventional VAV systems, The VAV/BPFS is an electronically controlled system that provides costegectlve thermal comfort and acceptable indoor air quality Under controlled conditions In a chamber, a series experiments were performed to compare the ability of a VAV/BPFS to remove Indoor aerosol concentration and to reduce energy consumption no that ability of conventional VAV system. Results show that the VAV/BPFS Increases the effective ventilation rate and removes indoor air pollutant, and maintains acceptable indoor air Quality without sacrificing energy consumption.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.311-316
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• 2007

The improvement of speed and ride comfort requires a very horizontally and vertically rigid and non-flexible alignment. It is inevitable to construct many bridges depending on the topography of landscapes and obliged to lay turnouts on the bridges. In that case, special considerations have to be taken into account, i.e. permissible stresses of turnout components and limitations of displacements of bridge and turnouts. In this studies, numerical analyses for turnout/bridge interaction are carried out using commercial program LUSAS. The target of analytical model is the turnout layed near Pyeongrae-Hopyeng station on Kyeongchun line. The lead rail, stock rails, and the bridge are modelled using beam elements. Fasteners and ballast resistances are modelled using bi-linear spring elements. The turnout behaviors are investigated by varying the parameters such as span length of bridge, spring coefficients, and thermal loads.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.157-160
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• 2010

Management of indoor air quality of underground subway station is an important issue since the limited natural ventilation, limited sunshine incoming, and highly moistured atmosphere. The improvement in IAQ of platform is expected because most stations were installed with platform screen door currently, however, the poor air quality in tunnel might be affecting subway cabin indoor. In this study, we developed the air quality assessment model based on computational fluid dynamics. The geometry of air ventilation unit, seat, LCD monitors, and passengers were modeled using commercial software (Design Modeler) and fluid pattern and pollutants trajectories were analyzed by using CFX. We predicted the thermal comfort by predicted mean vote (PMV), distribution of CO2 and PM10 concentration. It is expected that this model can be used for the performance test of air cleaners which are under development.