• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권6호
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• pp.251-254
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• 2005

Animpedancecalculationmethodfortheirregularshapedpowerdistributionnetworksispresented.Theirregularshapedmetal-dielectric-metalboardissplitintothreepieceofsegmentstocalculatetheimpedancebetweenthetwoseparatedpointsontheboard.Transmission-matrixdescriptioncorrespondingtotheunitcolumnofboardandtheconnectionofunitcolumnboardareintroduced.Thenthetransmission-matrixfortheeachsegmentiscalculatedandreducedtothe2-portsimpedancematrix.Theproposedalgorithmisveryfastcomparingtheexistingmethods.Appliedtothe6inchby5inchsizeirregularshapedboard,theproposedmethodshows15timesfasterthantheelectromagneticorcircuitanalysismethod.

• 한국광학회지
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• 제4권3호
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• pp.294-300
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• 1993

표면광 마이크로 레잊, heterojunction phototransistor 그리고 저항을 단일 결정으로 성장시켜 집적시킨 NOR와 INVERTER 능동형 광 논리 소자에 대한 동작 특성을 조사하였다. 능동형 광 놀리 소자를 구성하는 개개 소자 중에서, 780 nm에서 발진하는 특정한 AlGaAs 초격자 마이크로 레이저의 미분 양자 효율은 15%로 나타났고, heterojunction phototransistor의 전류 이득은 에미터-컬렉터 전압이 4V이고, 입력 광의 세기가 $50{\mu}W$일 때 57으로 측정되었다. 직렬 저항이 370 ohm인 광 논리 소자의 출력은 입력광세기사 $47{\mu}W$일 때 $57{\mu}W$에서 $0{\mu}W$으로 감소하였다.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1742-1756
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• 2023

The hydrogen behavior in a nuclear containment vessel is a significant issue when discussing the potential of hydrogen combustion during a severe accident. After the Fukushima-Daiichi accident in Japan, we have investigated in-depth the hydrogen transport mechanisms by utilizing experimental and numerical approaches. Computational fluid dynamics is a powerful tool for better understanding the transport behavior of gas mixtures, including hydrogen. This paper describes a Large-eddy simulation of gas mixing driven by a high-buoyancy flow. We focused on the interaction behavior of heat and mass transfers driven by the horizontal high-buoyant flow during density stratification. For validation, the experimental data of the Containment InteGral effects Measurement Apparatus (CIGMA) facility were used. With a high-power heater for the gas-injection line in the CIGMA facility, a high-temperature flow of approximately 390 ℃ was injected into the test vessel. By using the CIGMA facility, we can extend the experimental data to the high-temperature region. The phenomenological discussion in this paper helps understand the heat and mass transfer induced by the high-buoyancy flow in the containment vessel during a severe accident.