• Journal of Electrical Engineering and Technology
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• 제7권5호
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• pp.759-764
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• 2012

In this paper, we propose a microwave hyperthermic lipolysis method to reduce subcutaneous fat without skin burn using external RF antenna. Since skin is closer to the antenna and has higher conductivity compared to the fat beneath, the temperature of the skin rises higher than that of the fat when the external antenna illuminates EM energy into a body, which may cause skin burn. In order to avoid the damages on skin, a skin cooling system is employed to the external antenna. The operating frequency is set at 5.8 GHz which is one of the ISM bands, to concentrate EM power efficiently on fat and not to heat up the muscle behind the fat. The operation time and RF power level has been determined based on experimental results with pork. The feasibility of the proposed method was shown by applying the method to the rat.

• 설비공학논문집
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• 제15권2호
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• pp.95-102
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• 2003

Optimization for the insulation thickness and external shape of a household refrigerator is peformed in order to minimize thermal load through the insulation wall. The one dimensional conduction heat transfer model is adopted to calculate thermal load. Calculus of variation is employed to optimize the thickness and shape of refrigerator or freezer. The uniform distribution of an insulation thickness and cubed external shape make thermal load minimize. Finally, by using both of the computational and experimental method, the thermal load is minimized for a refrigerator/freezer. It is shown that there exists optimal thickness of insulation walls and external shape for given the external cabinet dimensions and freezer and refrigerator internal volumes, Also, the analytical results are well agreed with the experimental results.

• 한국화재소방학회논문지
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• 제18권4호
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• pp.86-92
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• 2004

일정한 외부 복사열원(10, 15, 20, 25, and 35 ㎾/㎡)에 노출된 목재의 탄화속도를 측정하기 위해 목재의 종류별로 5개의 시료를 사용하였으며, 목재에 복사열원을 노출시키기 위해 Cone heater를 사용하였다. 시료의 크기는 100㎜×100㎜×50㎜로 Redwood, White oak, Douglas fir, Maple의 4종류의 목재를 사용하였다. 연구결과, 일정한 외부 복사열원에 노출된 목재의 탄화는 시간의 선형함수로 간주 될 수 있다. 일정한 외부 복사열원에 따른 목재의 종류별 탄화속도를 계산할 결과 Redwood가 가장 빠르게 나타나고. Douglas fir가 가장 느리게 나타났으며. 복사열원이 35㎾/㎡일 때 탄화속도는 10㎾/㎡일 때 보다 약 2배정도 빠르게 진행됨을 알 수 있었다. 식 (2)의 α 값은 외부복사열이 10, 15, 20, 25, 35㎾/㎡일 때 각각 1.02, 1.16, 1.23, 1.32, 1.44임을 평가할 수 있었다.

• 설비공학논문집
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• 제16권6호
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• pp.522-529
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• 2004

In this study, external condensation heat transfer coefficients (HTCs) of flammable refrigerants of propylene, propane, isobutane, butane, DME, and HFC32 were measured on a horizontal plain tube, 26 fpi low fin tube, and Turbo-C tube. All data were taken at the temperature of 39$^{\circ}C$ with a wall subcooling of 3∼8$^{\circ}C$. Test results showed a typical trend that condensation HTCs of flammable refrigerants decrease with increasing wall subcooling. HFC32 had the highest HTCs among the tested refrigerants showing 44% higher HTCs than those of HCFC22 while DME showed 28% higher HTCs than those of HCFC22. HTCs of propylene and butane were similar to those of HCFC22 while those of propane and isobutane were similar to those of HFC134a. Based upon the tested data, Nusselt's equation is modified to predict the plain tube data within a deviation of 3%. For 26 fpi low fin tube, Beatty and Katz equation predicted the data within a deviation of 7.3% for all flammable refrigerants tested. The heat transfer enhancement factors for the 26 fpi low fin and Turbo-C tubes were 4.6∼5.7 and 4.7∼6.9 respectively for the refrigerants tested indicating that the performance of Turbo-C tube is the best among the tubes tested.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.190-190
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• 1999

CHF (Critical heat flux) on the external surface of the reactor vessel lower head is major key in the evaluation on the feasibility of IVR-EVC (In-Vessel Retention through External Vessel Cooling) concept. To identify the CHF on the external surface, considerable works have been performed. Through the review on the previous works related to the CHF on the external surface, liquid subcooling, induced flow along the external surface, ICI (In-Core Instrument) nozzle and minimum gap are identified as major parameters. According to the present analysis, the effects of the ICI nozzle and minimum gap on CHF are pronounced at the upstream of test vessel: on the other hand, the induced flow considerably affects the CHF at downstream of test vessel. In addition, the subcooling effect is shown at all of test vessel, and decreases with the increase in the elevation of test vessel. In the real application of the IVR-EVC concept, vertical position is known as a limiting position, at which thermal margin is the minimum. So, it is very important to precisely predict the CHF at vertical position in a viewpoint of gaining more thermal margins. However, the effects of the liquid subcooling and induced flow do not seem to be adequately included in the CHF correlations suggested by previous works, especially at the downstream positions.

• 혜화의학회지
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• 제9권1호
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• pp.319-335
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• 2000

According to the literatual study on the external medical trearment of Menorrhalgia and Leucorrhea for gynecologic condition, the results were as follows. 1. Using external medical treatment for Menorrhalgia is to insert vagina theraphy, fumigation theraphy, to wash vagina theraphy, to insert anus theraphy, to apply hot pack theraphy and use with suppository such as BANSUKHWAN(礬石丸), SASANGZASAN(蛇床子散), KUMBONGHYUNGJU(金鳳衡珠) 2. Using external medical treatment for Leucorrhea is washing and fumigation on vagina, to wash vagina, to insert vagina, cleansing theraphy and use with Suppository such as YONGYEOMGO(龍鹽膏), KAMISASANGJASAN(加味蛇床子散), SASANGSACHUNGSEJE(蛇床子洗劑). 3. ANGELICAE GIGANTIS RADIX (當歸) is in mostly general use for external medical treatment of Menorrhalgia and Leucorrhea, in that order ANSU SEMEN(杏仁), EVODIAE FRUCTUS(吳茱萸), TORILIS FRUCTUS (蛇床子), CORYDALIS TUBER(玄胡索), CINIAMOMI CORTEX(肉桂), CARYOPHYLLI FLOS(丁香), ALUMEN(枯白礬), AQUILARIAE LIGNUM (沈香). 4. The efficacy of medicines to use external medical treatment is as follow to help circulation of blood, to warm spleen and stomach, to warm blood, to warm uterus and remove cold, to remove heat and dry moisture, to down heat-product, to contract bloodvessel, to counteract poison and destory virus, to make energy and blood. 5. KUMBONGHYUNGJU, made same size as cherry and shape vagina medicine, use for Menorrhalgia, menstural irregularity, Leucorrhea, it has the efficacy as follow to remove cold and dry moisture, to warm uterus, to help circulation and romove pain, to down moisture-heat.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.166-171
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• 2008

LNG carrier is a special-purpose vessel to transport natural gas (NG) from the place of origin to each consuming country. To increase the capacity of canying LNG carrier, the natural gas is conveyed as a state of liquid called LNG (Liquefied Natural Gas) during a voyage because the total volume of NG is surprisingly reduced when it is cooled down to $-162^{\circ}C$. That is why the design of insulation of the carriers is important to protect LNG from the external heat invasion, and it has been a great challenging subject for several decades in the shipbuilding industry. For this ultimate goal, the boil-off rate (BOR) needs to be accurately estimated during a voyage. Therefore, the goal of this study is to propose a numerical method for estimating the BOR of LNG for given insulation containment subject to external temperature conditions during voyage.

• 설비공학논문집
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• 제1권3호
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• pp.228-234
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• 1989

This paper describes the experimental thermal performance results of four experimental model buildings insulated differently. For the purpose of examining the thermal characteristics of external walls and indoor thermal conditions, four experimental model buildings are constructed as externally insulated, internally insulated, non-insulated &light-weight curtain wall types with different K-values and heat capacities, respectively.
Through the measurements of temperatures at various points and solar insolation, the effects of insulation and heat capacities are evaluated, and the evaluated effects of each experimental model buildings are compared. Hence, the characteristics of temperature profiles, time-lag effects and decrement factors are discovered.

• 수산해양교육연구
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• 제21권3호
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• pp.400-408
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• 2009

The purpose of this study is to know the concept of Eco-industrial Park and How to use the thermal effluents from power plants. Thermal effluents, which use sea water for cooling, from power plants have been discharged with about $6{\sim}7^{\circ}C$ higher temperature than near sea area. Therefore, it could effect on the marine ecosystem as a external pressure factor that increase the artificial thermal load in near sea area. The applications of thermal effluents had been surveyed through the several internal and external cases for utilizing heat sources and reducing the thermal load. As the precedence research for applying, the amount of heat sources of thermal effluents was evaluated. When the thermal effluents was fully applied in heat sources and available heat, assume that use heating season by 12 hours a day of demanded available heat, it was possible to calculate total 198 Tcal of energy saving.

• 융복합기술연구소 논문집
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• 제7권1호
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• pp.1-6
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• 2017

The Heat exchanger for deep geothermal system is very important to enhance the efficiency of the system. The co-axial heat exchanger is used due to the limitation of digging space. The heat transfer on the external surface of outer pipe should be high to receive a large amount of heat from the ground. However, the inner pipe should be insulated to reduce the heat loss and increase the temperature of discharge water. This study made experiment apparatus to describe the co-axial heat exchanger and measure the heat transfer coefficients on the internal and external surface. And the pin-fin was designed and fixed on the internal surface to increase the efficiency of heat exchanger. Finally, we calculated the temperature of discharge water using the heat transfer circuit of co-axial heat exchanger and heat transfer coefficient which from experimental results. The water temperature was reached the ground temperature at -500 m and following the ground temperature. When the water return to the ground surface, the water temperature was decreased due to heat loss. As the pin-fin case, the heat transfer coefficient on the internal surface was decreased by 30% and it mean that the pin-fin help to insulate the inner pipe. However, the discharge water temperature did not change although pin-fin fixed on the inner pipe.