• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.35 no.2
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• pp.47-51
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• 2006

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5457-5463
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• 2011

The objective of this study is to investigate cooling performance characteristics of mobile air conditioning system using R744 as an alternative of R-134a. In order to analyze the cooling performance characteristics of the air conditioning system using R744 for a passenger vehicle, the developed air conditioning system using R744 was applied in a real passenger vehicle and tested under various operating conditions with the variation of gas-cooler inlet air conditions, evaporator inlet air temperatures and compressor speeds. As a result, cooling capacity and coefficient of performance (COP) of the tested air conditioning system decreased with the rise of the inlet air temperature of the gas cooler but increased with the rise of the inlet air temperature of the evaporator. In addition, cooling capacity and coefficient of performance (COP) increased by 42.2 % with the rise of the compressor speed from 900 rev/min to 1800 rev/min, but it decreased by 55.4%.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.35 no.7
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• pp.26-30
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• 2006

천연가스 수요관리를 위한 효율향상 방안을 기기별(주방용, 난방용, 냉방용, 열병합발전, 수송용)로 기술하고, 국외의 수요관리 사례와 동향에 대해서 알아본다.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.208-211
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• 2009

To reduce the peak demand the promotion of gas cooling(absorption chillers and GHPs) is required. In this study the effect of electric power peak-cut has been analyzed using two methods. One is based on monthly LNG consumption data and the other is using the gas cooling capacity installed. Both methods agreed well with each other within the uncertainty of 20%. It was found that the gas cooling had the peak cut effect of 1,500-2,000 MW for recent 5 years (2003 - 2007). The ratio of gas cooling to the whole cooling demand was 12-15%, which is needed to be increased.

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.209-209
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• 2005

• Journal of Animal Environmental Science
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• v.16 no.2
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• pp.99-108
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• 2010

The principal objective of this study was to investigate the cooling effects of geothermal heat pump system (GHPS) in farrowing house. A total of 96 sows were allocated to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in summer season. During the experimental period of four weeks, the highest outside temperature observed was approximately $34.1^{\circ}C$, GHPS decrease indoor temperature of pig housing up to $30.9^{\circ}C$, but conventional pig housing was similar to outside temperature. Dust concentrations (maximum 61.4%) of particulate matter less than $10{\mu}m$ (PM 10) in GHPS-housing were lower than the conventional housing. GHPS showed no signigicant difference in carbon dioxide emission, whereas the ammonia gas concentration was significantly decreased in GHPS-housing compared to that of conventional housing. Sows in GHPS-housing showed significantly lower respiratory rate than those of the control group. GHPS did not affect hormone level, litter size and birth weight, but weaning weight of piglets was influenced by GHPS. Feed consumption of sows was significantly increased in GHPS-housing compared to the conventional hosing. These results suggest that GHPS decrease dust concentration, ammonia gas emission and indoor temperature of pig housing and may affect performance in sows and weaned piglets.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.9
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• pp.721-729
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• 2014

A hybrid desiccant cooling system (HDCS) that uses a heat pump driven by district heating instead of a sensible rotor can provide an increased energy efficiency in summer. In this paper, the summer operation costs and initial costs of both the HDCS and traditional systems are analyzed using annual equal payments, and national benefits are found from using the HDCS instead of traditional systems. In the analysis results, the HDCS reduces the operation cost by 30 compared to the traditional systems, and each HDCS unit has 0.079 TOE per year of primary energy savings and 0.835 $TCO_2$ per year of $CO_2$ emission reduction more than the traditional systems. If HDCSs were to be installed in 680,000 households by 2020, this would produce a replacement power effect of 463 MW. Despite this savings effect, HDCSs require a government subsidy before they can be supplied because the initial cost is higher than that of traditional systems. Thus, this paper calculates suitable subsidies and suggests a supply method for HDCSs considering the national benefits.

• 보일러설비
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• no.1 s.144
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• pp.104-109
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• 2006

올해도 그리 밝지만은 않을 것으로 예상되는 보일러 시장은 각 보일러업체들의 다양한 사업다각화가 두드러질 것으로 보인다. 겨울 한철 사업으로 여름내내 성수기가 되기만을 기다리던 때와는 달리 냉방사업을 통해 줄어드는 보일러 물량을 채우고 일본과 유럽지역에 호황을 누리고 있는 가스 · 기름온수기를 출시해 사업의 다각화를 꾀할 예정이다. 특히 각 사가 내세우는 거꾸로 타는 기술과 공기 비례제어 기술, 똑바로 타는 기술 등이 한층 업그레이드돼 소비자들을 찾을 것으로 전망된다. 이제는 모두 다 같은 기술과 마케팅 전략이 아닌 각 업체들이 지닌 신기술과 노하우만이 보일러 시장을 공략해 갈 수 있을 것으로 판단된다.

• The Magazine for Energy Service Companies
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• s.31
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• pp.14-15
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• 2004

현재 에너지 및 자원사업 특별회계(에특회계) 예산에 ESCO자금 지원을 별도로 반영해 지원 방안을 강구할 예정이며 전력산업기반기금을 이용해 발전차액 지원도 검토중에 있습니다. 또 여름철에 한해 소형열병합 발전용 가스요금을 현재의 냉방용 요금 수준으로 인하할 계획이며 현재 9개 지역에 적용되고 있는 열병합용 요금 지역을 확대할 계획입니다.

• NEWSLETTER 전기공업
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• no.92-13 s.56
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• pp.1-17
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• 1992