• 대한기계학회논문집
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• 제3권1호
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• pp.1-9
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• 1979

Methanol was examined as supplemental fuel for open chamber type and pre-combustion chamber type diesel engine. Pre-determined quantities of diesel oil were injected as ordinary diesel engines and methanol was added at inlet pipe using venturi, nozzel and and float chamber for the rest of the charge. In this mode of operation, addition of methanol reduced inlet and exhaust temperature. Inlet air quantities were essentially unchanged in spite of lower inlet temperature. Exhaust smoke was significantly reduced At light load when both diesel oil and methanol were introduced with small quantities, specific heat consumption was considerably increased. However, with the increase of the quantity of methanol or diesel oil, specific heat consumption was improved. With sufficient quantities of diesel oil enough to produce the power above 3/4 load, addition of methanol showed better thermal economy.

• 비파괴검사학회지
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• 제21권4호
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• pp.383-390
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• 2001

Long-range guided wave inspection is a new emerging technology for rapidly and globally inspecting a large area of a structure from a single test location. This paper describes a general overview of the guided wave properties and its application for long-range inspection of structures the principle and instrument system for a guided wave inspection technology called "magnetostrictive sensor (MsS)" that generates and detects guided waves electromagnetically in the material under testing, and examples of long-range guided wave inspection of structures that can be accomplished using the MsS.

• 한국자동차공학회논문집
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• 제13권5호
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• pp.57-63
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• 2005

The effects of an urea injection at the exhaust pipe for a 4-cylinder DI(Direct Injection) diesel engine were investigated with the parameters such as urea-SCR(Selective Catalytic Reduction) and EGR system. The urea quantity was controlled by NOx quantity and MAF(Manifold Air Flow). The urea injection quantity can be controlled with the urea syringe pump, precisely. The effects of NOx reduction for the urea-SCR system were investigated with and without ECR engine, respectively. It was concluded that the SUF(Stoichiometric Urea Flow) is calculated and the NOx results are visualized with engine speed and load. Furthermore, the NOx map is made from this experimental results. It was suggested, therefore, that NOx reduction effects of the urea-SCR system without the EGR engine were better than that with the EGR engine except of low load and low speed.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2011년도 추계학술논문발표회 논문집
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• pp.83-86
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• 2011

옥내소화전설비, 스프링클러설비 등 수계소화설비에 일반배관용 스테인리스강관과 그 연결에 필요한 이음쇠의 사용가능성을 적용사례, 내식성 등을 통해 확인하였고, 기존 수계소화 설비의 배관에 대한 개선방안을 도출하였다. 일반배관용 스테인리스강관 및 이음쇠는 국내의 경우 수도용으로 활발히 사용되고 있으며, 독일 영국 일본 미국 등의 수계소화설비에 사용되고 있음을 확인할 수 있었다. 강관과 이음쇠의 연결상태에서 내식성을 확인하기 위해 0.5 %와 3.5 %의 소금물을 관내에 주입한 후 28일 보관한 결과 이상이 없음을 확인하였다. 또한, 기존에 설치되어있는 수계소화설비는 배관계의 온도차에 의한 보상방법이 되어있지 않아 작동물질의 열팽창에 따라 강관, 이음쇠의 파손이 발생할 수 있음을 확인하었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1221-1226
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• 2008

Present, the cooling method of using a phase-change heat transfer such as immersed type, heat pipe etc is applied in cooling of high-capacity power semiconductors of the main power system for the high speed train with the concentrated traction. In order to apply these phase-change cooling system to the high speed EMU to be developed, needed are technological researches of consideration of installing space, air passage, light weight material and miniaturization. Although this research establishes design specifications through theoretical analysis and computational analysis from the basic design process of the cooling system of the propulsion system for the high-speed EMU, when details design is completed, present improvement subject and optimum design before manufacturing the prototype of the cooling system on the basis of analysis results. And then, carried out will be the performance tests through prototype manufacture and reliability estimation by components of cooling system.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.262-265
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• 2004

As a cryogen, LOx is a light blue, odorless, transparent liquid. Also it is not shock sensitive and does not decompose. However, it is a strong oxidizer and will vigorously support combustion. Therefore all harmful contaminants (such as grease, oil, fingerprint and organic materials) that could cause malfunctions, fires, or explosions in a oxygen environments must be completely removed prior to the introduction of oxygen. Especially, grease ingredient located inside of the LOx supply line, pipe and PHS (Pneumo-Hydraulic System) part can make drastic chemical reaction with oxygen. Therefore, to protect rapid reaction such as explosion, grease ingredient must be surely eliminated by a regular and irregular degreasing. Study on the availability, effectiveness and selection of degreasing detergents and method is described in this paper, and it will be useful for the construction and management of IPP test facility.

• KIEAE Journal
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• 제2권1호
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• pp.63-68
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• 2002

Solar sunlighting systems are useful to apply for most buildings. This study aims to analysis the development and architectural application of solar sunlighting systems. For the purpose, abroad developing situation of solar sunlighting systems were investigated and analyzed literally. And, by case studies, architectural application methods are analyzed. As results, light pipe systems are mainly used for small building and houses. Also solar mirror systems are used for atrium and underground spaces. Lens-fiber systems are applied for high rise buildings and office buildings which internally have no influx of sunlighting. Some application suggestion in our country are discussed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.910-913
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• 2005

The pipe which it uses from the nuclear power plant or factory by a long period use and a corrosive action the inside defect occurs on the inside. abstract here. The ESPI method is in order to investigate the laser light in the measurement object it will be able to measure the wide territory whole in once, does not receive an effect in direction of defect not to be. has the strong point it will be able to measure a change of place arrowhead real-time defect. It measured a inside defect of pressure vessel by using ESPI and FEM. It compared a each method result.

• 에너지공학
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• 제26권2호
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• pp.64-72
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• 2017

중동지역 환경에 적합한 70 W급 LED 조명등의 성능분석을 집중변수모델을 이용하여 수행하였다. LED 조명등은 발열기판, 히프파이프, 방열판으로 구성된다. LED 조명등을 4개의 물체로 구분하고, 각각에 대해 에너지평형을 적용하여, 4개의 연립 비선형미분방정식 형태의 집중변수모델을 수립하였다. 연립 방정식의 해는 Runge-Kutta법을 이용하여 구하였다. 집중변수모델의 대류열전달계수는 다차원해석을 통하여 구하였으며, 실험결과와 비교한 결과, 발열기판은 $1.5^{\circ}C$, 상부방열판에서 $1.8^{\circ}C$의 오차를 가지며, 상대오차는 약 0.6 %임을 확인하였다. 이 모델을 이용하여 대기온도가 $55^{\circ}C$인 정상 운전조건, 태양광만 주어질 때의 조건, 태양광이 주어진 상태에서의 비정상 운전조건, 상부방열판이 없는 경우 등에 대한 온도분포분석을 수행하였다.

• 한국압력기기공학회 논문집
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• 제12권1호
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• pp.126-133
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• 2016

Recently, the research and development of Sodium-cooled Fast Reactors (SFRs) have made progresses. However, liquid sodium, the coolant of an SFR, is chemically unstable and sodium fire can be occurred when liquid sodium leaks from sodium pipe. To reduce the damage by the sodium fire, many fire walls and fire extinguishers are needed for SFRs. LBB concept in SFR might reduce the scale of sodium fire and decrease or eliminate fire walls and fire extinguishers. Therefore, LBB concept can contribute to improve economic efficiency and to strengthen defense-in depth safety. The LBB assessment procedure has been well established, and has been used significantly in light water reactors (LWRs). However, an LBB assessment of an SFR is more complicated because SFRs are operated in elevated temperature regions. In such a region, because creep damage may occur in a material, thereby growing defects, an LBB assessment of an SFR should consider elevated temperature effects. The procedure and method for this purpose are provided in RCC-MRx A16, which is a French code. In this study, LBB assessment was performed for PGSFR IHTS hot-leg pipe according to RCC-MRx A16 and the applicability of the code was discussed.