• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.922-927
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• 2009

Due to the law of use of sustainable alternative energy recently legislated, many public institutions are ordered to use renewable energy. So it gets people's eyes on Geothermal energy system among other suggested renewable energy. Since there is hardly existence of a volcanic region, Geothermal heat pump system is generally used most in Korea. However, the important technology and materials are not localized and further, with only our technical skills it is arduous to popularize and develop Geothermal energy because of lack of revitalization related to the law and the regime for locally suitable Data-base. Moreover, an access of renewable energy is too much hard because of people's low interests about Geothermal energy. But fortunately, the well-studied about Geothermal heat system started to be adopted in many other provinces. Therefore, we study this with intend to popularize and develop Geothermal energy.

• KIEAE Journal
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• v.13 no.2
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• pp.123-130
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• 2013

The primary goal of this research is to identify the impacts of window design on the energy use in buildings which takes up about 25% of the total energy consumption. Recently, efficient use of energy is gaining more importance in buildings. Window design, especially being dependent on glazing performance choices, is an important factor for reducing energy consumption in most of the buildings. It also is influenced by the latitude of the site and window orientation. This paper aims at identifying the influence of Window performance indicators(U-value, SHGC), orientation and latitude on the building energy consumption with systematically designed simulations. Comparative study has been performed for five different locations; Greenland, Korea, Singapore, Argentina and Chile along with the different window U-value and SHGC values. The results show that optimum window system with properly coordinated window performance indicators(U-value, SHGC), orientation achieves dramatic reduction of energy consumptions. Windows with low U-value could reduce heating loads and high SHGC could reduce cooling loads. The study also verifies that the windows installed at south facade is more energy efficient in the northern hemisphere while windows facing north is more energy efficient in the southern hemisphere.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.1115-1118
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• 2010

최근 실내공기질에 대한 관심이 높아지면서 실내공기질을 쾌적하게 유지하기 위한 다양한 기술에 대한 연구가 활발히 이루어지고 있다. 기존에는 미세먼지와 부유미생물 등이 가장 중요한 오염물질이었으나, 최근에는 이산화탄소가 크게 각광받고 있다. 이산화탄소는 그 자체가 환기의 지표이기도 하지만, 최근의 저탄소 녹색성장 기조에 따라 환기에 의한 냉난방 에너지 비용을 절감하는 방안에 대한 관심도 크게 높아지고 있다. 본 연구에서는 제올라이트를 이용하여 실내공간의 이산화탄소를 제어하는 방안에 대하여 기술하였다. 소형 lab-scale의 이산화탄소 흡착성능 평가시스템을 제작하고, 이를 이용하여 제올라이트의 이산화탄소의 흡착성능을 알아보았다. 또한, 본 시스템의 실용화를 위해서는 이산화탄소가 흡착한 제올라이트의 재생이 필요한데, 이를 위하여 다양한 온도와 압력 등의 조건 하에서 이산화탄소의 탈착성능을 TSA/PSA를 이용하여 알아보았다. 흡착실험을 통하여 제올라이트를 이용한 실내공간용 이산화탄소의 저감 효과를 확인할 수 있었다. 그러나, 탈착실험 결과 2~5회 정도 열탈착 시킨 후에는 이산화탄소의 흡착 성능이 현저하게 감소하여, 이를 개선하기 위한 방안의 개발이 필요함을 알 수 있었다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.3
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• pp.205-211
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• 2012

Unlike the previous approaches, we analyzed for economic efficiency of renewed heating and cooling systems as the characteristics of space. The purpose of this study is to analysis the energy consumption and economical efficiency of absorption chillers and EHP systems in renovated library. It is important that equipment selection should be considering energy cost as well as space program. In recently, many EHP systems were installed in the building for reducing the energy cost and for seeking the convenience of individual control. In contrast, though absorption chillers have the disadvantage of a central control, absorption chillers are appropriate for the conditions of the library that needs simultaneous operation. The results by payback period method, show that selection of heating and cooling systems should be consider for space program and the characteristics of space.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.280-286
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• 2008

In this study, characteristics simulation of heat pump system is investigated for heating and cooling using sewage water as a heat source. A simulation program for preestimate operation characteristics of heat pump system is developed. The performance of this system is resolved by several variables and the characteristics which is based on actual air and sewage temperature data. The simulation results agree well with the experimental values of COP. In the analysis of system characteristics, the COP is changed between $3\sim5$ in winter season for heating load, $4\sim6$ in summer season for cooling load. As the results of Life Cycle Cost analysis over a 15 year life cycle, the energy cost could be reduced by 250 million won if a heat pump system was used instead of a conventional boiler and an absorbtion refrigerator on the office building.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.12
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• pp.947-954
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• 2006

Building energy consumption according to the ventilation has been considered to be an important subject. The purpose of this study is to investigate the cooling and heating loads in a test space with a forced ventilating system. In the test space, on/off controlled air-conditioning and forced ventilating facility were operated between 8 : 30 to 21 : 00 during 4 days and some important data like temperatures and energy consumption were measured to obtain actual thermal loads. The simulation was carried out in a mode of temperature level control using a TRNSYS 15.3 with a precisely measured air change amount and performance data of air-conditioner. Heating load and cooling load including sensible and latent were compared between by experiment and by simulation. Both of thermal loads associated with ventilation show a close agreement within an engineering tolerance.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.12
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• pp.565-571
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• 2014

Nowadays, to make buildings light weight and aesthetically pleasing, curtain wall structure are commonly used. Therefore, window to wall ratio is increasing, which has caused cooling and heating load in crease in buildings as well. This phenomenon has negative impact from energy point of view. This paper analyzes window and wall convective heat gain when the slat reflectance of external and internal blinds are changed for the better understanding of the fundamentals behind the phenomena. It was observed that, if slat reflectance is increased, window transmitted solar increases and convection heat rate is clearly affected. Among six surfaces including four walls, ceiling and floor, maximum convection heat rate occurs on the south wall in summer. On the other hand, ceiling and floor showed the lowest convection heat gain, since they are shared by adjacent floors.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.11
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• pp.53-58
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• 2015

Systemic heating and cooling air conditioning systems are popular in various industrial fields and even home. Recently, the rate of supply of this kind of multi-heat pump has been increased under ESCO financing supporting system. Generally the heat pumping system has a structural simplicity and easy installation benefits. and has good running efficiency under normal designed condition. But under extreme climate condition (over $+30^{\circ}C$, under $-10^{\circ}C$), this system exposes abnormal power consumption. It causes high progressive electric power rates and resultant peak power capacity of power plant. In this paper, a novel system concept of buffering refrigerant accumulator and constant pressure control system to relieve peak power load is proposed and this system's utility is verified with an prototype experimental system.

• Journal of the Korean Institute of Gas
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• v.14 no.1
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• pp.15-20
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• 2010

The interest on the utilization of landfill gases and biogases for energy production has been increasing due to environment concerns and global warming caused by burning fossil fuels, renewable nature of these gases. Using those synthesis gases to generate energy with engine encourages more efficient collection reducing emissions into the atmosphere and generates revenues for the operators. However the lower calorific value of synthesis gases than that of LPG or CNG affects the combustion stability and power output. Thus it becomes necessary to address disadvantages involved by studying synthesis gases in technological perspective. This paper discussed synthesis gas as a fuel for 60kW dual-fuel engine to produce power in an effective way. The methane diluted with $N_2$ was used as a fuel and developed ECU and injector driver facilitated the investigations with diesel fuel.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.42-46
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• 2017

As $CO_2$ emission with imprudent using fossil fuel, annual mean temperature of earth is increased in every year. Geothermal energy is inexhaustible energy resource to solve this problem. Heat pump performance and heat exchange efficiency of ground loop are important to distribute widely. Thus, this study are performed to increase heat pump performance and heat exchange efficiency of ground loop with dual expansion valves and spacer. As a results, COP of cooling & heating is obtained improvement up to 11.4% using dual expansion valves, and heat exchange efficiency is increased up to 17.5% using spacer. It will be reduced initial installation cost due to increasing heat pump performance and heat exchange efficiency of ground loop.