• 설비공학논문집
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• 제22권5호
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• pp.296-303
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• 2010

An experimental study was carried out to investigate performance characteristics of the hybrid solar system during spring season. The system operating condition, each load, and heat pump performance were analyzed with the cloud cover. As a results, the collector heat, solar fraction, and hot water load were decreased with a rise of the cloud. The heating load was considerably effected by the ambient temperature regardless of the cloud cover. Besides, the temperature of hot water increased with the solar radiation. The COP of the heat pump was significantly influenced by the ambient temperature, that was 2.09~2.46 for gray day and 1.94~2.71 for fair day, respectively.

• 한국염색가공학회지
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• 제10권4호
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• pp.7-14
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• 1998

Microwaves are high frequency radiation capable of generating very rapid, uniform and efficient heating of textile material. Microwave heated dyeing of polyester fabric was tried with different solvent systems, irradiation time and dye concentration. Microwave fixation methods were used with 100% water,30% urea, EG and DMF, respectively, pad-baths in which the padded fabrics were exposed over a heated or boiling water bath to maintain sufficient moisture content during irradiation. In order to ascertain the relation between the dyeing property of polyester fabric and the microwave irradiation condition caused by microwave heating, the K/S values and fastness properties of dyed fabrics such as light, washing and sublimation fastness were measured.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.366-368
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• 1999

In this paper, the analysis of the gas flow in the GCB is presented by using the modified FLIC method and the arc model. The modified FLIC method has two step calculation procedure. And it adopts the upwind scheme, which results in the stability.[1] The arc model used in this paper makes arc a heating source in the energy equation. The heating source is composed of ohmic heating and radiation energy transfer. And the type of the GCB in this paper is a auto-expansion type.[2]

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.52-57
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• 2007

The control characteristics for radiant panel heating system with automatic thermostatic valves were researched by computer simulation and experiment. The unsteady energy analysis using equivalent R-C circuit method and radiation heat transfer analysis of enclosure analysis method with simple structured rooms was performed. The results of flow rate changes of the simulation study are good fit with the ones of experimental one.

• 한국식품과학회지
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• 제10권1호
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• pp.88-91
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• 1978

식중독(食中毒) 세균인 Salmonella enteritidis와 S. typhimurium에 방사선과 열(熱)($45^{\circ}C$ 또는 $50^{\circ}C$에서 10분)을 병용(倂用)처리한 바, 처리순서에 따라 살균작용에 현저한 차이가 나타났다. 방사선조사(照射)후에 가열한 것은 상승효과를 보였으나 방사선조사(照射)전에 가열한 것은 오히려 반대 효과를 보였으며 그 영향은 가열온도에 따라 다소 차이가 있었다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.927-932
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• 2006

A simulation and experimental study for energy flow dynamics of floor radiant heating system were performed. The study was done under both environmental chamber and a house with several rooms. The unsteady energy analysis method using equivalent R-C circuit and radiation heat transfer analysis of enclosure analysis method with simple structured rooms were used for computer simulation. Also, first order dynamics with time delay in analyzing the return water was considered. The results of temperature changes of the simulation study are good fit with the ones of experimental one.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.178-184
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• 2022

Renewable energy sources based on solar radiation, wind energy, geothermal energy, and biomass energy have now reached the level of industrial application. A new way to generate electricity using low-potential heat is to install a hydro-steam turbine. In hydro-steam turbines, hot water is supplied directly to turbine rotor nozzles without prior separation into steam and water in separators, which significantly increases the efficiency of hot water energy use. Such turbines are suggested to be used as autonomous energy sources in geothermal heating systems, heating water boilers and cooling systems of chemical reactors, metallurgical furnaces, etc. The authors conclude that the installation of hydro-steam turbines in heating plants and process boiler plants can also be effective if the used exhaust steam-water mixture at the turbine outlet is used to heat the network water or as return water.

• 한국산업융합학회 논문집
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• 제3권4호
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• pp.307-317
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• 2000

The purpose of this study is to form a calculation formula of the mean skin temperature on the human body in a heated room by the use of floor heating system. Korean traditional floor heating system is a long way from being defunct. The floor heating systems based on hot water have been coming into wide use mainly in the apartment house. However, it is considered that the design process and evaluation method for the floor heating systems in the standpoint of human being are not established so far. In the floor heating systems, air temperature as well as floor temperature should be considered as physical factors which affect the sensation of human body. Furthermore, extremely few studies have been performed on the sitting with legs crossed posture sedentary which is the typical dwelling life style of residents from the ancient times in Korea, while a large number of studies on the influence of the floor heating systems on the human body in standing and sitting on a chair sedentary have been carried out. Especially, it is essential to elucidate how mean skin temperature on the human body is affected by thermal conduction in the contact area between the sitting with legs crossed posture sedentary human body and floor including thermal radiation due to the combination of air temperature and floor temperature, but the studies dealt with such issues have hardly been performed. Based on the above statements, the influence of the environment condition due to the combination of air temperature and floor temperature is discussed in the present investigation through theoretical of mean skin temperature on the human body in the floor heating systems.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.21-27
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• 2008

In this study, the design of the solar heating system for district heating as well as it's operating characteristics and the performance analysis was carried out. This solar district heating system was composed of two different types of solar collector circuit, flat plate and vacuum tube solar collector, in a system. This system supply constant temperature of hot water without solar buffer tank. For this, the proportional(variable flow rate) control was used. The experimental facility for this study was used the Bundang district solar heating system which was installed in the end of 2006. The operating characteristics and behaviour of each collector circuits are investigated especially for the system design and control. The yearly solar thermal efficiency is 47.5% on the basis of aperture area and 39.8% on the basis of gross area of collector. As a result this solar heating system without solar buffer tank and with proportional controller was testified a very effective and simplified system for district heating. It varied especially depend on the weather condition like as solar radiation and ambient temperature.

• Design & Manufacturing
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• 제14권4호
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• pp.17-24
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• 2020

Products for heating indoors in low temperature and dry winter are largely divided into products using fossil fuels and products using electricity. The fossil fuels can warm the entire space by convection, but there is a high risk of fire and the frequent ventilation due to the increase in carbon monoxide and carbon dioxide. Heaters using electricity are mainly used because they are convenient to use and are cheap. However, these products can not efficiently warm the air because they use radiation energy. In other words, only the front part exposed to the heater is warm, and the rear part has no heating effect at all. Also, because it emits a large amount of light, fatigue of the eyes is very high. Another problem is that when using electric heaters, the room tends to be dry by high heat. Indoor humidity maintenance is a very important factor in the prevention and treatment of respiratory diseases. Especially, it is essential for health care for infants, bronchial organs and people with weak respiratory because humidity is low in winter. In this study, we conducted a study to develop a product that can improve heating efficiency while maintaining proper indoor humidity by combining heat energy and moisture particles. The concept of humidification and heating at the same time, moisture particles generated in the humidifier pass through the heater, include thermal energy, and the moisture particles with thermal energy are diffused into the space by forced convection, thereby warming the entire space. In addition, the heating time is shortened as the feeling temperature is increased with the high relative humidity, and this has the effect that the heating cost in winter is reduced.