• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.505-510
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• 2001

Advanced Pressurized Reactor 1400(APR1400), which is a standard evolutionary advanced light water reactor(ALWR), has been developed from 1992 as one of long-term Government Project(G-7). The APR-1400 is designed to operate at the rated output of 4000MWt to produce an electric power output of around 1450MWe. Due to the increased electric power, In Nuclear Power plant huge quantities of heat are generated in the thermo-dynamic process used for producing electrical energy. So, There is considerationly additional cooling, Heat transfer area and increased cooling water of Heat Exchanger which take care of the different smaller cooling duties within the nuclear power plant. We review applying to PRE instead of Shell-and-Tube Heat exchanger. In this paper, we describe the major design features of PRE, Comparison between a PHE and a Shell-and-Tube Heat Exchanger, and then Applicability of Plate Heat Exchanger in Nuclear Power Plant Component Cooling water systems.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.639-646
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• 2000

Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season in Korea. However, since the heat efficiency of the heater is about 80%, considerable unused heat in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust gas heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The system consists of a heat exchanger made of copper pipes, ${\phi}\;12.7{\times}0.7t$ located inside the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tame The total heat exchanger area is $1.5m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to performance test it can recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690{\ell}$/hr from the waste heat discharged. The exhaust gas temperature left from the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{circ}C$ from $21^{circ}C$ at the water flow rate of $690{\ell}$/hr. And, the condensed water amount varies from 16 to $43m{\ell}$ at the same water circulation rates. This condensing heat recovery system can reduce boiler fuel consumption amount in a day by 34% according to the feasibility study of the actual mimitomato greenhouse. No combustion load was observed in the hot air heater.

• 대한전자공학회논문지
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• 제21권5호
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• pp.90-99
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• 1984

양면에서 텅스텐 램프를 조사하는 실리콘 재결정시의 SOI(silicon-on-insulator) 다층구조에 대한 1차원적 온도 및 열원(열원)의 분포를 SOR(successive over-relaxation)방법을 이용하여 정상상태의 열방정식의 해로부터 구하였다. 열원의 분포는 광원의 스펙트럼, SOI sample 내부 계면에서의 다중반사, 광흡수 계수의 온도, 주파수 의존성 등을 고려하여 구하였으며, 열 방정식의 경계조건이 되는 wafer의 전면과 후면의 온도는 혹체복사 조건으로부터 구하였다. 내부계면에서는 전도열속(conduction heat flux)과 복사열속(radiation heat flux)에 의한 연속조건을 만족하도록 하였다. 본 문제에서의 온도분포와 열원의 분포는 상호간에 큰 영향을 주게 되므로, 두가지 변수가 일치되는 값을 보일 때까지 iteration을 계속하였다. Pyrometer을 이용하여 측정한 wafer 전면의 온도는 약1200°K이었고 이때의 simulation 결과는 1120°K 정도로 나타났다.

• 마이크로전자및패키징학회지
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• 제10권4호
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• pp.35-38
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• 2003

ITO/glass 기판 위에 발광물질로서 poly(2-methoxy-5-(2-ethylhexoxy)-1,4-phenylenevinylene (MEH-PPV)를 이용하여 스핀코팅법(spin coating)으로 Glass/ITOM/MEH-PPV/Al 구조를 가지는 고분자 유기 발광 다이오드를 제작하였다. MEH-PPV 박막형성시 열처리온도에 따른 다이오드의 전기적, 광학적 특성을 조사하였다. 열처리 온도를 $65^{\circ}C$에서 $170^{\circ}C$로 증가함에 따라 유기 발광다이오드의 발광휘도는 10V 인가전압에서 630 cd/$\m^2$에서 280 cd/$\m^2$로 크게 감소하였다. 또한 $65^{\circ}C$에서 열처리한 시료의 경우 약 2 lm/W의 최대 발광효율을 나타내었다. 이러한 결과는 높은 온도에서 열처리시 MEH-PPV 유기 형광층과 전극간의 상호반응에 의한 계면 거칠기의 증가와 새로운 절연층의 형성 등과 관련이 있는것으로 판단된다.

• 대한기계학회논문집B
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• 제26권7호
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• pp.1022-1030
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• 2002

The experiments were performed with a $31{\times}31{\times}7mm^3$ simulated 3-dimensional module on the thermal conductive board of a parallel plate channel. The convective thermal conductance for the path from the module surface directly to airflow and conjugate thermal conductance for the path leading from the module to the floor by way of a module support, then, to the airflow were determined with several combinations of module-support-construction(210, 0.32, 0.021 K/W)/floor-material(398, 0.236W/mK) and channel height(15-30mm). As the result, it was found that the conjugate thermal conductance and the temperature distribution around the module depend on the thermal resistance of the module support, and the channel height. These configurations were designed to investigate on the feasibility of using the substrate as an effective heat spreader in the forced convective air-cooling of surface mounted heat source. The experimental results were discussed in the light of interactive nature of heat transfer through two paths, one directed from the module to the airflow and the other via the module support and the floor to the air.

• 열처리공학회지
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• 제17권2호
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• pp.73-77
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• 2004

The efforts which increase the strength of the auto-body structure and decrease its weight lead to develop a new concept of part production systems, such as Post-Form Strengthening by induction heat treatment. In this study, several cold and hot-rolled sheet steels were used to find out optimum induction heat treatment conditions. After induction heat treatment, strength of heat-treated sheet steels was increased significantly compared with that of as-rolled steels. From these results, auto-body structure which has more light and safe has been made by using this induction hardening method.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.800-808
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• 1998

In this study the thermal stress distribution and deformantion characteristics resulting from the nonuniform temperature fields of the cylinder block of a light 3-cylinder 4-stroke gasoline engine were analyzed using the 3-dimensional finite element method. The temperature distributions req-uisite for the thermoelastic behavior alalysis were obtained from the steady-state heat conduction analysis performed on the basis of experimental data. in order to examine the effect of a ceramic material the cylinder liner was replaced by the silicon nitride($Si_{3}N_{4}$) and its thermal behaviors were compared with those of the original block.

• 한국진공학회지
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• 제20권4호
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• pp.280-287
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• 2011

열전소자를 사용하여 발광다이오드의 방열효과를 조사하였다. 열전소자의 냉각기능인 펠티에 효과(Peltier effect)를 이용하여, 고전력 발광다이오드의 방열과 p-n접합부의 온도를 제어하였다. 정격전류(350 mA)에 대한 고전력(1 W급) 발광다이오드(Light Emitting Diodes: LEDs)의 온도와 p-n접합부 온도는 각각 $64.5^{\circ}C$와 $79.1^{\circ}C$이다. 열전소자의 입력 전력 0.1~0.2 W에 대하여, LED의 온도와 접합부 온도는 각각 $54.2^{\circ}C$와 $68.9^{\circ}C$로 낮아진다. 열전소자에 입력 전력을 0.2 W 이상으로 증가할수록, LED의 온도와 접합부의 온도가 상승한다. 이는 열전소자에 의하여 흡수된 열이 LED로 역류하기 때문이다. 따라서 열전 소자의 냉각기능을 유지하기 위하는 열의 역류를 제어하여야 하며, 열의 역류는 LED의 온도와 방열장치의 온도 차가 클수록 커진다.

• 한국철도학회논문집
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• 제7권1호
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• pp.55-59
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• 2004

Composite materials were used widely due to merit of light weight, low maintenance cost and easy installation. But it is the cause of enormous casualties to men and properties because of weak about the fire. Particularly, it is more serious in case of subway train installed composite materials. For this reason, experimental comparison has been done fur measuring heat release rate(H.R.R) and smoke production rate(S.P.R) of interior panels of electric motor car using cone calorimeter. A high radiative heat flux of 50kW/㎡ was used to bum out all materials and to simulate the condition of fully developed fire case in the tests. It was observed that Heat Release Rate and Smoke Production Rate curves were dependent on the kinds of the interior materials. From the heat release rate curves, the sustained ignition time, peak heat release rate and total heat release rate were deduced, These data are useful in classifying the materials by calculating two parameters describing the possibility to flashover.

• 한국생산제조학회지
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• 제8권2호
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• pp.50-55
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• 1999

The exhaust emissions from diesel vehicle are known to be harmful to human health and environment. Recently, one of the most environment problems is particulate matter. In this study, through the actual exper iment and heat transfer of exhaust pipe in light duty diesel engine equipped with the ceramic filter trap of throttling type, following results are obtained. 1. In case of light duty diesel engine equipped with ceramic filter trap of throttling type, Power and torque of engine were decreased about 5%, compared with the case without trap system. It means that was not so much effect on base engine performance.2. If the length of exhaust pipe when equipping with ceramic filter trap is suitably controlled, the range of regeneration will be expand much more.3. Particulate matter reduction efficiency of ceramic filter trap system was about 70%-80%, so it was proved a good system to reduce particulate matter.In experiment, test was conducted to estimate engine emission in 2,476cc light duty diesel engine which was equipped with ceramic filter trap.