• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.146-152
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• 2016

This paper describes a multi-physics analysis of a high resolution winding type resolver and rotary transformer using FEM (Finite Element Method). The rotary transformer boosts the input voltage to a high voltage which can be input into the rotor windings of the resolver. Through multi-physics models of the transformer and resolver, the characteristics of the output signals for the resolver system with high resolution can be derived. Moreover, the circuit model of the interface part between the transformer and resolver should be considered, because of the calculation of the input current to the resolver. The winding type resolver is composed of 32x and 1x stator windings for high resolution. Then, the output signals of the stator windings, which make sinusoidal SIN and COS waves with a $90^{\circ}$ phase difference, are verified.

• Tunnel and Underground Space
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• v.16 no.1 s.60
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• pp.38-49
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• 2006

LNG storage in lined rock cavern demands various techniques concerned with rock mechanics, thermo-mechanics and hydrogeology in design, construction and maintenance stage. LNG pilot cavern was constructed in Daejeon in order to verify these techniques. In this paper, evaluation of drainage system and ice ring formation was studied by numerical simulation. By Modflow analysis in the viewpoint of aquifer and Seep/W analysis in the viewpoint of flow system, it was verified that the drainage system in the pilot cavern was efficiently operated. Since ice ring formation can be simulated by interactive relation between heat transfer and water flow, coupled analysis of those was performed. In this analysis, the position of ice ring was presumed and it was demonstrated that the formation is affected by velocity and direction of groundwater flow.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.192-193
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• 2016

본 논문은 계통 전원 정전 시 계통 전원을 대신하여 전력을 엘리베이터 구동 시스템에 공급함으로써 정전으로 기동이 정지된 엘리베이터 내부에 고립된 승객에 대한 비상구출 운전을 실시하는 자동 비상 구출 운전 시스템의 축전지 충전 회로에 관한 Simulink 및 PSpice 연동 해석 모델 개발을 실시한다.

• Journal of Aerospace System Engineering
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• v.11 no.3
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• pp.1-7
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• 2017

The applications of high-frequency induction heating has recently been studied in various industrial fields. In this study, induction heating is applied to a SCM440 specimen that is widely used in industry. The specimen was made up of a cylinder 20 mm in diameter and 160 mm long. An induction heating power supply module was used to generate heat in the cylinder at a high frequency (approximately 85 kHz) for 50 seconds. The temperature of the specimen was measured at the 150 mm length in 5 second intervals. Results such as joule heat and temperature are compared with the numerical model analysis using an electromagnetic-thermal co-simulation technique. The analytical model of the cylinder was modeled by considering the skin effect. The median measured temperature after induction heating was conducted for 50 seconds was $57.65^{\circ}C$, compared to a predicted analytical value of $57.27^{\circ}C$. Thus, the analytical results are in good agreement with the experimental results, and this model can predict the induction heating phenomenon numerically.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.536-542
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• 2017

A great deal of difficulty is encountered in the thermo-mechanical analyses of nozzle assembly for solid propellant rocket motors. The main issue in this paper is the modeling of the boundary conditions and the connections between the various components-gaps, relative movements of the components, contacts, friction, etc. This paper evaluated the complex phenomena of nozzle assembly during burning time with co-simulation which include fluid, thermal surface reaction/ablation and structural analysis. The validity of this approach was verified by comparison of analysis results with measured strains.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.36-43
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• 2018

A great deal of difficulty is encountered in the thermo-mechanical analyses of nozzle assemblies for solid propellant rocket motors. The main issue in this paper is the modeling of the boundary conditions and the connections between the various components-gaps, relative movements of the components, contacts, friction, etc. This paper evaluates the complex phenomena of nozzle assemblies during burning time with co-simulations that include fluid, thermal surface reaction/ablation, and structural analysis. The validity of this approach is verified via comparison of analysis results with measured strains.

• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.208-211
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• 2008

본 논문에서는, 연료전지의 비선형 출력특성으로 인한 전력변환장치 (PCS)의 특성해석을 위해 Matlab Simulink로 구성된 고분자 전해질 연료전지(PEMFC)와 PSIM으로 구성된 PCS의 연동 시뮬레이션 기법에 대하여 기술한다. 또한 제안된 연동 시뮬레이션을 기반으로 PEMFC 특성을 갖는 전원과 이상적인 정전압원이 PCS에 입력되었을 경우 나타나는 특성 시뮬레이션을 통해 비교 분석하고, 이를 통해 연료전지-PCS 연동 시뮬레이션의 필요성을 제시한다.

• The KIPS Transactions:PartA
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• v.10A no.2
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• pp.101-110
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• 2003

ECMAScript can support VXML in utilizing the system information, analysis of complex equation, iterative execution, declaration of functions and their call, etc. However, since the ECMAScript is the standard script language for Internet, there is no way that the script lithely connects with VXML. In this paper, we presented the design and implemented the interpreter that meets the requirement of ECMAScript for its flexible connection with VXML. For connections, we added some functions in modified ECMAScript : management of VXML variables, execution of system functions, analysis of equations and function calls. From the result of connection, it is shown that new ECMAScript can handle the various algorithms of VXML.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.88.2-88.2
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• 2011

본 연구는 아연/공기전지 설계기술 개발을 위한 기초 연구로서 전산해석을 이용하여 전해질 유동에 따른 아연/공기전지의 성능 예측에 관한 것이다. 전산해석모델은 전기화학 방정식과 유체유동 방정식으로 구성하였으며, 화학종 반응에 관한 지배방정식으로는 Nernst-Planck식을 이용하였고 전극표면의 전기화학반응은 Butler-Volmer식을 이용하였다. 또한 유체유동 방정식은 Navier-Stoke식을 적용하여 전해질 유동에 따른 전기화학적 성능 변화를 모사하였다. 아연/공기전지 성능 평가 실험으로부터 얻은 I-V 곡선과 전산해석결과와의 비교/분석을 통하여 전기화학모델의 타당성을 검증하였으며, 유체 유동 방정식과의 연동해석을 적용하여 전해질 유입 위치 및 유입 속도에 따른 아연/공기전지의 성능 변화를 조사하였다. 아연/공기전지의 성능은 전해질 유입 위치가 아연극에 가까울수록, 유입 속도가 빠를수록 향상되는 것을 확인할 수 있었다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1993.05a
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• pp.16-17
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• 1993

하우스에 대하여 풍하중을 고려한 구조해석을 수행할 때 적용하는 풍력계수는 각국마다 차이가 있고 우리나라에서도 실험이나 이론적으로 규명된 바가 거의 없는 실정이다. 따라서 현 실정에 맞는 하우스의 구조해석에 필요한 풍력계수에 대한 규명이 필요할 것으로 판단된다. 이에 본 연구는 단동, 2연동 및 3연동하우스에 대하여 풍동실험을 통해 측정된 풍압을 이용하여 풍력계수를 산정하고 그 변화를 규명하여 풍하중 산정에 필요한 합리적인 풍력계수 분포 단면도를 작성하기 위한 기초 자료를 제공하기 위하여 수행되었다. (중략)