• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.3
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• pp.321-331
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• 1999

A numerical study is carried out for increasing heat removal using indirect cooling system. Computation is performed for nine cases as variation of flow condition in the lower channel. As the result of this study, water is more effective than air at the same pressure loss in spite of the lower inlet velocity. In channel configuration, the vertical channel is more effective than horizontal channel because of the buoyancy effect. Under the condition that heat generation is the same, counter flow effectively decreases the temperature difference among blocks. Parallel flow is more effective than counter flow when average temperature of all blocks is considered. In the case of installing obstacles in the lower channel, it is desirable to install obstacles in the bottom of lower channel. Heat transfer rate increases as the height of obstacles increases.

• Korean Journal of Acupuncture
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• v.27 no.1
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• pp.23-30
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• 2010

목적 : 본 연구는 간접구의 안전성에 대한 기초 데이터를 확보하기 위하여 수행되었다. 연구설계 : 50명의 건강한 성인을 무작위 배정으로 두 그룹으로 나누어 4주간 (일주일에 3회) 신궐혈과 관원혈에 뜸을 시술하였다. 시험군에 비하여 대조군은 열이 전달되지 않도록 단열제로 처리한 뜸으로 동일한 부위에 시술하였다. 첫 시술 1시간 전과 마지막 시술 1시간 후에 공복상태에서 채혈을 하여 혈액학적 검사를 시행하였다. 결과 : 혈액학적 검사에서 적혈구와 총 백혈구 및 백혈구의 종류별 절대수치와 상대수치에서 두 그룹 간에 특별한 차이가 없었다. 또한 혈청학적 검사에서 총 단백질, 알부민, AST, ALT, ALP, GGT, LDH, 요소질소, 크레아티닌, 총콜레스테롤 및 중성지방의 비교에서도 그룹 간에 차이가 없었다. 결론 : 본 연구는 건강한 사람에서 간접구의 시행 후 혈액학적 안전성을 처음으로 보고하는 것으로서, 향후 뜸의 연구를 수행시 중요한 비교 자료로 사용될 수 있을 것이다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.2
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• pp.178-183
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• 2012

To simulate space thermal environment in thermal vacuum test, direct or in-direct heater has been applied on the radiator. Both of them, direct heater attached on the radiator and indirect heater with a distance from the radiator, simulate the heat fluxes from the Sun radiation, the Earth IR and Albedo. They also supply the heat fluxes to the radiator of spacecraft to achieve the target temperature according to thermal test conditions. In general, indirect heater is used when the heater is not allowed to attach on the radiator directly due to constraints of coating property or contamination. For in-direct heater design, it is needed to estimate the heat power to make the extreme test conditions and minimize the interference with heat exchange of radiator and shroud. In this study, optimized thermal design of in-direct heater is proposed and investigated by commercial S/W SINDA. The effective values of design factors are also derived.

• Solar Energy
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• v.10 no.2
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• pp.18-27
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• 1990

The hot water producer by the combination of the solar thermal energy and freon gas compression heat has been developed. Freon R-12 gas was circulated through the system including the solar absorption panel, which has no glassing and no insulation, and the frozen and burst problems were intrinsically eliminated. The manufacturing and running costs may go further down than the regular solar hot water systems.

• Journal of Energy Engineering
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• v.27 no.4
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• pp.20-26
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• 2018

As the global warming due to greenhouse effect has become serious problem, it is necessary to introduce the technology, for instance, such as diversity or saving of energy to reduce the use of fossil fuel. The purpose of this study was to investigate the characteristics on materials of absorption plate, unpowered and minimum use of power in cooling and heating combined device. As the results, it was observed that, in case of summer, since temperature of absorption device of solar heat(ADSH) was lower than that of no ADSH, cooling effect was insignificant in case of being not installed cold-reservoir. However, in case of winter, heating effect was certified even though the power was not used. At secondhand, the performance of ADSH with Cu was higher 2 times than that of ADSH with Al.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.88-100
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• 2013

This study evaluated the direct and indirect environmental impacts of various unit operations of a industrial waste incineration plant by using the life cycle assessment tool and reviewed the improvement plan. During the incineration process, the direct environmental impact was decreased with decrease in emission of various air pollutants by incorporating an air pollution prevention facilities. However, an increase in indirect environmental impacts was observed as a consequence of resources and energy of consumption at the various operational facilities. Consequently, quantitative direct and indirect impact were 89.1%, 10.9%, respectively. The environmental impact analysis of system revealed the highest impact of incineration followed by the impacts of other unit processes such as semidry reactor, and bag-filter. The various air pollutants and ashes generated during the incineration process caused the most significant environmental impact. Among the various categories of environmental impact, global warming accounted the highest impact(more than 85%) followed by eutrophication, and abiotic depletion. As a result of the avoided impact by the utilization of heat generated during the waste incineration process, using an incineration heat for steam and electricity obtained the impact reduction of 45.5%, 19.8%. So, during siting of new incineration plant, the utilization of steam generated from the waste combustion is highly considered to reduce the environmental impact.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.115-118
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• 2010

2 Types of heater (Vitiated Type, Clean Air Type) in order to increase the temperature for a test are used for industry. In this report, large capacity clean air type heater was designed. Heater capacity and LNG consumption rate can be calculated by the air mass flow and heater inlet/outlet temperature. The heater is composed by Burner, Furnace, Heat Exchanger, and Stack. The hot air from the burner and cold air from the tube inlet exchange their heat indirectly in the heat exchanger, so the desired temperature can be achieved at the exit of the tube.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.161-162
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• 2011

신재생에너지는 자연계에 존재하는 에너지원으로 이용하는 이상의 속도로 재생되는 에너지원이다. 그 에너지원은 태양, 풍력, 조력 등으로 사실상 고갈되지 않는 에너지원이며 또한 수력, 태양광, 태양열, 조력, 풍력, 지열, 바이오매스 등의 형태로 이용된다. 이들 에너지원은 직접, 또는 간접적으로 이용하는 경우가 있다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.377-383
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• 2000

급속한 경제 성장에 따른 산업구조의 고도화 및 다양화로 인하여 유기용제는 많은 사업장에서 널리 사용되는 물질의 하나로 종류도 매우 다양해져 400여종 이상이 되며/sup 1)/, 사용량도 매년 10%이상 증가하고 있어 근로자에게 직접 또는 간접적으로 폭로되어 건강에 나쁜 영향을 초래하고 있다. 유기용제에 의한 건강 장해를 예방하기 위해서는 유기용제의 사용 실태파악과 정확한 작업환경측정 및 평가를 통한 작업환경관리가 산업위생학적 견지에서 매우 중요하다고 생각할 수 있다/sup 2)/.(중략)

• Solar Energy
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• v.8 no.1
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• pp.74-81
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• 1988

A preliminary study has been done to investigate the thermal performance of an indirect system. Direct systems are also analyzed and the results are compared with those of the indirect system where possible. Values from the numerical simulation show very good agreement with the measured data. Although the indirect system is generally expensive and not as efficient as direct systems, it is more reliable in frigid weather conditions like the winters in Korea.