• 설비공학논문집
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• 제16권2호
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• pp.128-134
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• 2004

In order to verify and take measures against a variety of troubles which cannot be predicted in a well-controlled laboratory, it is necessary that solar system should be experimented in an actual situation during a long period. Through this experiment it can be also understood how the load pattern and operational conditions expected in a design process become different to those in the actual running, which can be applied to a new system design. We installed 6 kW solar hot water heating system with a shower facility and operated during 7 months. As a result, average 8.3 persons took a shower a day； solar fraction is 71％ and total collector efficiency is 40％ during the periods from March to September. We confirmed several troubles encountered in the actual situation and considered practical center-measures.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.206-210
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• 2012

Ground source heat pump is a central heating and cooling system that pumps heat to or from the ground. Building Integrated Geothermal system used in this experiment is one of the Ground Source Heat Pump Systems which utilize energy pile. The purpose of this study is to evaluate heating performance of the system. The building is a low-energy experiment apartment in Yonsei University Songdo Campus and the subject is one of the energy reduced houses in this apartment. In the experiment, indoor temperature, outdoor temperature and the inlet and outlet temperature of ground heat exchanger and subject model, were measured. Then the heat pump's Coefficient of performance(COP) of the heat pump was calculated. As a result, the COP of heat pump is 4-5. Although the depth of the ground heat exchanger in this experiment is shallower than usual heat exchanger, the result of heating performance of this system was good as well.

• 한국농공학회지
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• 제40권3호
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• pp.94-102
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• 1998

This experiment was carried out to study on the effect of greenhouse heating by water-to-water heat pump system employing heating water tank(ground water) as the heat source. Followings are the results obtained from this study ; 1. The heat amount absorbed from evaporator and the heat amount rejected from condenser were approximately 9, 000~ 12, 000kcal/h and 13, 000~ 17, OOOkcal/h, respectively. 2. The heat efficiencies of evaporator and condenser used in this experiment were approximately 79% and 83%, respectively. 3. The maximum heating load estimated for the experimental greenhouse was about 18, 000 ~ 25, OOOkcal/h, which was found to be about 28 ~ 32% higher than the heating capacity of the heat pump system adopted for this experiment. 4. The coefficients of performance(COP) for the heat pump and the total heat pump system were approximately 2.9~3.5 and 1.5~2.4, respectively. 5. The coefficient of performance(COP) calculated from the Mollier Diagram was about 3.2 ~ 3.4, which was reasonably close to the COP estimated on the basis of measured values. 6. The temperature of experimental greenhouse heated by the heat pump system could be maintained about 12~15 。C higher than that of a control greenhouse.

• 한국가금학회지
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• 제26권3호
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• pp.189-193
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• 1999

This experiment was conducted to investigate the effect of floor heating system on housing environment and performance in broiler production. PVC heating pipes(in 25cm spacing) were covered with concrete under the litter. Floor heating system was compared with conventional direct heating system. Each treatment had two replicates of 110 birds each. Litter moisture content was significantly reduced in floor heating system than conventional direct heating system(P〈0.05). Dust concentration was higher in floor heating system because of low litter moisture content. CO$_2$concentration was 2,900ppm and 1,500ppm on the direct heating system and floor heating system, respectively at the age of 1 week. Body weight was significantly higher in floor heating system at 7 weeks of age(P〈0.05). The results of the trial show that floor heating was useful heating system for broiler production.

• 한국안전학회지
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• 제26권5호
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• pp.65-72
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• 2011

The use of waste concrete can resolve the environmental pollution and shortage of natural aggregate. However, recycled aggregate includes substantial amount of cement paste. So, these aggregates are more porous, and less resistant to mechanical actions than natural aggregates. So, recently, the new manufacture processes of high quality recycled aggregates were suggested such as heating and solving to acid liquid. But the method of solving to acid liquid is not economical and produces additional environmental pollution. In this paper, for the purpose of manufacture of high quality recycled aggregates, the heating processes was added to the existing process of recycled aggregates. To find the optimum process, the experiment was performed by using the method of statistical experiment design, and the heating temperatures(4 levels : 300, 450, 600 and $750^{\circ}C$) and heating times(4 levels : 5, 20, 40, 60 minute) were main experimental variables. By the test results, the optimum manufacturing condition of coarse recycled aggregate was $600^{\circ}C$ and 40 minute, and for the fine recycled aggregate, a little heating made a satisfaction to the KS standard quality code.

• 한국지구과학회지
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• 제30권1호
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• pp.58-68
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• 2009

몬순 기간에 구름의 복사 강제력의 영향을 파악하기 위하여 1998년 4월부터 9월까지 International Satellite Cloud Climatology Project (ISCCP) 구름자료와 GEWEX Asian Monsoon Experiment (GAME) 재분석 자료를 입력 자료로 복사 모델을 수행하여 3차원의 장파 복사 플럭스를 구하였다. 구름에 의한 대기 복사 가열은 구름을 포함한 평균 대기와 맑은 대기에서의 복사 가열율의 차이를 이용하여 계산하였다 구름에 의한 복사 가열율이 아시아 몬순에 미치는 영향을 중점적으로 살펴보았다. 구름에 의한 복사 가열은 인도양에서 최대를 티벳 고원에서 최소를 나타내어, 남북으로 차등 가열의 경도를 나타내었다. 이러한 차등 가열이 대기 순환의 최대 원인임을 고려해볼 때, 인도양과 티벳 고원에서의 구름에 의한 차등 가열의 경도는 해들리 타입의 남북 몬순 순환을 강화시키고 있다. 또한 운정에서의 가열, 운저에서의 냉각의 형태로 나타나는 구름의 복사 가열 분포는, 대기의 불안정성을 높여서 몬순 순환을 증대시킬 수 있는 역할을 하고 있다.

• 동력기계공학회지
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• 제19권4호
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• pp.69-75
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• 2015

In this study, the characteristics of heating performance of a high-performance air-cooled heat pump with vapor-injection(VI) cycle using re-heater was investigated experimentally. Devices used in the experiment is consist of a VI compressor, condenser, oil separator, refrigerant (economizer outlet refrigerant) re-heater, economizer, evaporator. And R410A was used as a working fluid. The experiment was conducted with two cycles(cycles A and B) for investigating heating performance. In case of cycle B, heat exchange was conducted by re-heater between outlet refrigerant of compressor and suction refrigerant of the VI system(Fig.1, re-heater). But the re-heater was not used in case of cycle A. As a result of this experiment, discharge temperature of refrigerator in compressor was shown higher value, when the cycle B was conducted, because of the heat exchange between suction refrigerant of VI cycle and outlet refrigerant of compressor in the re-heater than cycle A that was not use re-heater. it means that liquid hammer and the decrement of heating performance can be decreased by using re-heater. Also, Heating coefficient of performance(COPh) was shown about 2.98 in Cycle B which was 4% higher than Cycle A and from these results, It was confirmed that the improvement of the heating performance of heat pump with VI cycle can be achieved by applying re-heater.

• 한국의류학회지
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• 제41권4호
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• pp.687-697
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• 2017

To figure out an appropriate pressure level for a body warming base layer, human responses were observed when the pattern reduction of base layers varied. Under the condition of $2^{\circ}C$, 60% RH, 0.1m/s, ten male subjects participated in the experiment with four sizes of experimental vests where heating pads were attached. The subjective evaluations of the heating vests with different sizes were reported using 7 or 9 point scales. We simultaneously observed chest, abdomen and scapula skin temperatures and microclimate humidity. It was found that the tight pattern as in the case of A or B provided a warmer subjective sensation and skin temperature than C or D; however, there were no differences in skin temperature at the chest. Eventually, the chest temperature decreased after about 30 mins of heating; however, temperature of abdomen increased and indicated that heating with two commercial pads used was inadequate for whole body warming. The pressure sensation of 'tight' was improved after warming the abdomen in a cold environment. Overall, the gaps beyond the original circumference of the abdomen, as in C or D, were not desirable for the local heating of abdomen under the conditions of this experiment where walking was included in the protocol. The experiment garment B with nude waist circumference was the best, and D with the largest ease, was the worst for a comfortable warming vest.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.121-128
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• 2005

This is about experimental comparison study between convective heating and radiation heating system to use the design criteria for residential house. Experiment was done in EC(environment chamber) under simultaneous outdoor condition for 4 kinds of heating system such as CRHP(Ceiling Radiant Heating Panel), BEHC( Bottom Electric Heating Coil Mat), EFCU( Electric Fan Coil Unit) and CEHU( Convective Electric Heating Unit). Result show that CRHP ,which is radiation heating system, can consume more 23% energy than convective heating system when it is operated by dry bulb temperature but can save 1 ${\sim}$ 10% when operated by glove temperature and 27% when operated by MRT.

• 한국지열·수열에너지학회논문집
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• 제16권4호
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• pp.16-23
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• 2020

In this study, the control characteristics and effects of control methods on heating performance and energy consumption for the hot water floor radiant heating control system of a residential apartment were research by experiment. As a control method, On-Off control and outdoor reset control methods with GRNN(General Regression Neural Network) and without GRNN are considered. Also, the control performances with regard to improvement of indoor thermal environment and reduction of energy consumption are compared, respectively. Experiment results show that the performance of the control method with GRNN is better than that of conventional on-off control method without GRNN in the responses of room set temperature and energy saving.