• Journal of Biosystems Engineering
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• 제25권5호
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• pp.385-390
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• 2000

The heat pump is one of heating and cooling systems driven by electricity using natural energy as a heat source. The heat pump system was mainly adopted to a cooling system or a refrigeration system. In regions with a large amount of electricity, it is used as a heating system or a heating and cooling system of houses, buildings and agricultural facilities. During cold weather, air source heat pumps do not work well because of some technical problems, such as frosting on evaporator coil when outside air temperature is below -5$^{\circ}C$. In this research, the heat regenerative technology was employed to eliminate the frosting on evaporator coil and improve the COP of the heat pump system. This fiber belt heat regeneration system(FBHRS) has very simple structure consisting of a geared motor and a porous fiber belt passing through alternatively between cold and warm air duct. The laboratory test showed that the heat pump system with a FBHRS yielded an impressive COP higher than 3.5 at the outside air temperature of -7$^{\circ}C$ in heating mode.

• 동력기계공학회지
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• 제17권6호
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• pp.136-141
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• 2013

This study introduces and analyzes the energy for heating and cooling system in region with volcano-stratigraphic. The thermodynamic properties of air through the air blower installed at the entrance of borehole are measured. It estimates the availability of underground air for heating and cooling system through experimental data and theoretical analysis. Based on our conclusion from these calculations we predict possibility of over 40kW steady and stable energy source from underground. Therefore this underground air can be utilized in region with volcano-stratigraphic.

• 한국태양에너지학회 논문집
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• 제28권4호
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• pp.43-49
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• 2008

The purpose of this study is to present the simulation results and an overview of the performance assessment of a solar heating & cooling system by means of the $200m^2$ evacuated tube solar collector. The simulation was carried out using the thermal simulation code TRNSYS with new model of a single-effect LiBr/$H_{2}O$ absorption chiller developed by this study. The calculation was performed for yearly long-term thermal performance and for two design factors: the solar hot water storage tank and the cold water storage tank. As a result, it was anticipated that the yearly mean system efficiency is 46.7% and the solar fraction for the heating, cooling and hot water supply are about 84.4 %, 41.7% and 72.4%, respectively.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.1125-1130
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• 2006

An air source heat pump system producing the ice and water storage energy for cooling and heating of building has been proposed. Cycle design and simulation considering energy balance between heating and cooling capacity has been carried out. The roles of the capacity controlled compressor, refrigerant heating device and air preheating are investigated in detail. System control logic for meeting the predetermined heating capacity when the system is operated at cold climate condition is suggested. Some anticipated problems of the proposed system are also described.

• 한국인터넷방송통신학회논문지
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• 제20권6호
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• pp.65-70
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• 2020

본 논문에서는 고효율의 냉난방시스템을 구축하기 위해 냉방기와 난방기를 한 대로 동시에 할 수 있는 냉난방 동시형 멀티 에어컨 시스템을 개발하고 하이브리드형 식물공장에 적용하여 복합형 농장의 자동화가 가능하도록 하였다. 이를 위하여 난방시에 응축기 기능을 하는 열교환기가 냉방시에는 증발기 기능을 하도록 함으로써 냉난방을 동시에 구현하도록 하였다. 실험을 위하여 냉난방 동시형 멀티 에어컨시스템을 제작하고 농장의 식물공장에 적용시켜 식물의 재배 및 보관, 건조 등을 할 수 있도록 하였다. 그 결과 하나의 시스템으로 냉난방을 동시에 해결하는 에너지 절약 시스템으로 농산물의 온도환경을 조절할 수 있었으며 에어컨과 보일러를 동시에 설치하지 않아도 되는 공조시스템을 구현하여 효율적인 농작물 관리가 가능하였다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.33-38
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• 2009

Energy loss from windows accounts for large scores of heating and cooling loads also in energy saving apartments that is reduced over 30% of total energy consumption. Movable reflective insulations, insulation shutters, blinds, insulated shades are used to reduce energy loads from windows. In this study, energy saving performance of insulated shades was simulated by control methods. According to installation of insulated shades, heating loads were decreased about $10.5{\sim}11.3%$, and cooling loads are decreased about $11.0{\sim}15.5%$ on an energy saving apartment. The heating peak load was reduced about 9.5% by insulated shades, but the cooling peak load is hardly ever decreased. Because in the condition of cooling peak load, latent cooling loads accounts for large score of cooling loads. Difference of the energy loads by a schedule control method and an outdoor detection control was no more than 5% for a base model. In the case of insulated shades with automatic control system, simple time schedule control system would be more efficient than outdoor detection control system that should use several sensors.

• 설비공학논문집
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• 제25권1호
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• pp.1-6
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• 2013

This study aims to reduce cooling energy by grasping kinds of heating load in building in order to decrease cooling energy in summer and eliminate efficiently heating load. Lighting heating value was confirmed through examination and experiment concerning lighting heating and reducible exhaustion value was extracted lighting apparatus. The optimal exhaust system by air conditioning type was suggested for applying lighting heat exhaust system and the method contributing to promotion supplying low energy architecture was suggested by predicting reduced cooling load.

• 한국유체기계학회 논문집
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• 제15권3호
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• pp.57-63
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• 2012

Effects of coolant pre-cooling and fuel pre-heating on the performance of a combined cycle using a F-class gas turbine were investigated. Coolant pre-cooling results in an increase of power output but a decrease in efficiency. Performance variation due to the fuel pre-heating depends on the location of the heat source for the pre-heating in the bottoming cycle (heat recovery steam generator). It was demonstrated that a careful selection of the heat source location would enhance efficiency with a minimal power penalty. The effect of combining the coolant pre-cooling and fuel pre-heating was also investigated. It was found that a favorable combination would yield power augmentation, while efficiency remains close to the reference value.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1099-1104
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• 2008

Recent year, mean energy consumptions of a people are higher than other country. And international oil price became over 120 dollar. This energy environment as well as energy war. Maybe, the Meteorological Administration is going to enforce scorching heatwave special report system from that come summer. Besides, 2008 summer, maximum demand power is expected by 64,240,000kW. The electric power equipment reserve rate appeared in to keep 12.5% level. Chilled water storage system witch is one of electric load administration system. Heat pump system used cooling tower heat recovery is advantage that use is possible to summer in small a public bath building. In this paper, we suggest that heat pump system by heat recovery using cooling tower when it is heating operation of ambient air temperature. To apply cooling tower heat recovery heat pump to chilled water heat storage type and achieved performance evaluation about operation. As a result, performance of heat pump system that about 121% in cooling mode, 138% in heating mode higher than KEPCO standard. And heating operation possible to ambient air temperature about $23^{\circ}C$, which of appear cooling tower outlet temperature about $13^{\circ}C$.

• 한국태양에너지학회 논문집
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• 제24권4호
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• pp.77-87
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• 2004

BIPV or double skin applied to the surface of the building, power and thermal load cannot both be increased. In the case of BIPV, because it is applied to the facade, incident solar energy decreases and efficiency drops off. The system in this paper complements these disadvantages and aims to decrease the heating & cooling load by transforming solar energy to electronic and thermal energy. The research in this paper is about the applicability of the clear PV attached double-skin system. And the PV electronic generation and the factors that affect the heating & cooling load such as the daily radiation, sun shading ratio, heating & cooling load, daylight luminance and glare distributions in the building are simulated.