• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.663-668
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• 2008

This study was carried out solar heating system design for district heating and it's the performance analysis by experiment. This experimental system was installed in Bundang district heating area in the end of 2006. The flat plate and vacuum tube solar collector are combined in one system. So district heating water is heated first by flat plate solar collector and than by vacuum tube solar collector. This solar heating system has not a solar buffer tank and is operating with variable flow rate to obtain a setting temperature of $90{\sim}95^{\circ}C$. As a result, the daily solar thermal collection efficiency is about 30 to 40% for the plate type and 50 to 55% for the vacuum tube solar collector. It varied especially depend on the weather condition like as solar radiation and ambient temperature. This variable flow rate system can be also reduced much pumping power more than 50%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.445-448
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• 2004

Radio frequency and microwave dielectric heating are well-known electroheating methods, used in industrial applications where non electrically conducting materials are to be heated, dried or otherwise processed. The major reason for considering this technique for any process is based on its unique ability to transfer heat into the volume of an electrically non conducting material such as insulator directly, rather than, via a surface. Conventional heating must first bring heat to the product surface and there after it depends on the physical characteristics and condition of the material as to how effectively this heat is transmitted into the mass. The product would suffer surface damage before the main body is adequately processed. Dielectric heating is applied to enhance conventional heating methods and to drastically shorten the required processing duration. Although the use of dielectric heating has been a well proven technique for several years in some industries, its application in the preheating of FRP has been limited by the insufficient experience. In this paper a method is described for uniform radio frequency heating of preheating of FRP.

• 설비공학논문집
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• 제3권5호
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• pp.404-414
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• 1991

The purpose of this study is to compare the amount of heating, domestic hot water, and cooking fuel consumption with that of heating fuel consumption by the existing calculation method and to provide rational heating system design and energy conservation through presenting the simplified equation which can anticipate the amount of heating, domestic hot water, and cooking and the load mechanical equipments. The affecting factors to the amount of energy consumption are the case of Heating, Domestic Hot Water and Cooking in addition to the energy conservation intention.

• 대한가정학회지
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• 제30권3호
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• pp.131-140
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• 1992

The purpose of this study was to investigate the heating regulation systems and the thermal environment of the Co-Generation apartment house in winter. Personal self-administration and interview method were used in the survey of this study. The respondents were 352 housewives who resided in Mokdong apartement using Co-Generation heating systems. Data was analyzed using SPSS PC+ computer package. The results of this study were summarised as follow; The typical patterns of heating regulation systems were intermittent and partial heating in the living room and bedroom exclusive of kitchen area. The present condition of the thermal environment were relatively warm in winter and Heatng regulation systems were influenced by type of location. Determinants of the thermal sensation and thermal comfort were the type of location of apartment as a architectural factor, clo as a personal factor.

• 설비공학논문집
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• 제13권8호
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• pp.746-756
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• 2001

An experimental study was conducted to investigated the effect of refrigerant flow control on the performance of a variable-speed heat pump operating in both cooling and heating mode. For this purpose, cooling and heating capacity, EER and refrigerant mass flow rate corresponding to an electronic valve as well as a capillary tube were measured as functions of compressor speed, length of capillary tube (or valve opening of the electronic valve), refrigerant charge, and outdoor temperature. From the comparison of experimental results, it was found that the performance variation due to the electronic valve opening became significant as the operating conditions(outdoor temperature and compressor speed) deviated from the standard condition at which heating capacity and EER were rated for the indicated capillary tube.

• 한국태양에너지학회 논문집
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• 제33권1호
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• pp.48-56
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• 2013

Energy consumption analysis of multi-family apartment is an important area of research for the design of energy-saving housing. In this study, we selected a universal type of Flat-type apartments and analyzed the heating energy consumption of variables such as U-value, G-value, infiltration rate, heating setpoint and boiler efficiency with EnergyPlus and eQUEST. With these results, we identify the characteristics of EnergyPlus and eQUEST and provided base data for the design of energy-saving housing. The results indicate that infiltration rate is the most important factors to consider. And eQUEST heating energy consumption is approximately 10% higher compared to the EnergyPlus under same condition.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.291-293
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• 2005

The purpose of this study is to evaluate the effects of line heating variables for forming the curved plate on the behavior of distortion using FEA and experiment. The optimum mixed ratio and standoff for flame heating was established under the heating conditions given in this study. With the heating condition, the predictive equation of angular distortion and transverse shrinkage was established using FEA and verified by comparing the predicted results and experimental results.

• 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.

• 한국건설순환자원학회논문집
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• 제8권1호
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• pp.11-17
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• 2013

폐기물 콘크리트의 사용은 환경 오염과 자연 골재의 부족을 해결할 수 있으나, 이러한 재생 골재는 골재 표면에 붙어 있는 시멘트 페이스트 량이 많아서 천연골재보다 더 많은 기포를 함유하고 있어 역학적 저항능력이 감소된다. 이러한 이유로, 최근에 고품질의 재활용 재생골재의 새로운 제조 공법으로 가열 등의 해결방법이 제안되어지고 있다. 본 논문에서는 고품질의 재활용 골재의 생산을 위해, 재생골재의 현존 제조공정에 가열 및 분쇄 공정을 추가하는 방법을 제안하였다. 최적의 프로세스를 찾기 위해서 통계적 실험계획법을 사용하여 실험을 수행하였고 가열 온도(4단계 : 300, 450, 600 및 $750^{\circ}C$) 및 가열 시간(4단계 : 5, 20, 40, 60분)이 주요 실험 변수였다. 시험 결과에 의해, 굵은 골재의 재활용을 위한 최적의 제조 조건은 $600^{\circ}C$와 40분으로 나타났다.

• 교육시설
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• 제7권3호
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• pp.5-14
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• 2000

The purpose of this study is to analyze the environmental characteristics of Hansung Girls' Middle & High School located on the northern slope of Mt. Naksan in Seoul but sited at different aspects. The measured temperature and illumination in March, July and December were analysed. The proportion of window size and questionaries were used also. The results of observation are as follows: (1) The temperature of the southward classrooms was $3.6^{\circ}C$ higher than eastward or westward classrooms in March, but the difference of the both values in July were only $0.3^{\circ}C$ in the average. (2) The temperatures in December decreased in the order of aspects: southward, westward and eastward. (3) The highest values for illumination appeared in the classroom faced to the south and the values decreased from westward to eastward. (4) Temperatures and illumination were varied not only with the aspect but also with the number of story and the proportion of the window size. However, the heating facilities and illuminators are installed evenly without considering the condition of the buildings. The heating facilities should be installed differently according to the direction and height of the story of the building. The heating facilities should be installed sparsely for the classrooms faced southward, and more densely near the hallway side to achieve satisfaction of students and to save expenses of heating. It will be better that electric power switches for window side have to be set separately from hallway side. Improvement of the condition of illumination and temperatures will help students to promote their health and learning.