• 한국자동차공학회논문집
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• 제9권5호
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• pp.30-37
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• 2001

Most gasoline engines employ a port injection system to achieve the better fuel-air mixing. A part of injected fuels adheres to the wall or intake valve and forms a film of liquid fuel. The other is secondarily atomized by the spray-wall interaction. A better understanding of this interaction will help in designing injection systems and controlling the strategies to improve engine performance and exhaust emissions. In the present research, the spray-wall interaction was investigated by a laser sheet visualization method. The shape of sprays was pictured at various impinging velocities and angles. The fuel dispersion was estimated by fluorescence light, and the atomization was evaluated by the enlarged images of droplets. The experimental results were compared with model predictions which are based on OPT method. The model has been modified to have the better agreement with the experimental result, and was implemented in the KIVA-II code.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.379-384
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• 2002

도로 건설 프로젝트는 대규모의 자본과 공기가 소요되는 프로젝트이다. 본 연구에서는 도로 프로젝트의 타당성분석 시스템 요소 기술 고찰과 기존의 타당성분석 자료를 통해 현행 방법의 문제점을 도출하고 이에 대한 개선 방안으로는 프로젝트별 정보축적을 통한 타당성 정보모델 구축을 제안하고자 한다. 이는 합리적 의사결정을 지원할 뿐 아니라 프로젝트 진행과정에서 발생 가능한 리스크를 초기 예측함으로서 프로젝트의 효율적 수행을 도울 것이다.

• 한국군사과학기술학회지
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• 제6권4호
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• pp.147-158
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• 2003

The prediction of wind field is very important fact in the radioactive and chemical warfare. In spite of advanced numerical weather prediction modelling and computing technology, the high resolution prediction of wind field is limited by the very high integration costs. In this study we coupled the mesoscale numerical model and microscale diagnostic numerical model with minimized integration costs. This coupled model has not only the ability of prediction of high resolution wind field including complex building but also microscale pollutant diffusion fields. For military operation this system can help making a practical and cost-effective decision in a battle field.

• 한국실내디자인학회논문집
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• 제19호
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• pp.121-127
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• 1999

The objective of this study was to criticize the model house of apartment and suggest a evaluation model which could be used as an effective tool. The evaluation model had been developed based on the theoretical framework suggested by previous results of research related on housing design, which comprised the following four components : 1) the paradigm of future home and life-style, 2) marketing effects of housing developer, 3) goals and principles of housing design and 4) results of user-preferences study, an evaluation model was suggested as a preliminary form which would be modified in detail after series of tests in the field. The evaluation model will be used to provide standardized criteria for the quality of model houses, and eventually help to improve the quality of apartment housing design by balanced information from theorist, user and developer.

• 융합보안논문지
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• 제16권5호
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• pp.81-86
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• 2016

최근 지속적으로 발생하는 보안위협은 기업의 비즈니스 연속성을 저해할 뿐만 아니라 사회적 국가적 차원에서도 그 심각성이 높아지고 있는 실정이다. 이러한 보안위협은 기업과 국가 간 경쟁력이 심화 되면서 기업의 지적 재산권 침해가 지속적으로 증가함에 따라, 기업들은 다양한 IT 컴플라이언스(compliance) 법제들에 대하여 의무적 준수와 더불어 엄격한 법적 책임을 부담하여야 한다. 따라서 본 연구에서는 기업의 능동적인 IT 컴플라이언스 활용을 위해 머신러닝(machine learning) 기술을 이용한 융합보안 컴플라이언스 관리 모델을 제안하고자 한다.

• 한국해양공학회지
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• 제16권6호
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• pp.1-6
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• 2002

The integration of Geographic Information Systems (GIS) with the hydrodynamic model was conducted in order to revitalize the use of geographical information and to aid in the understanding of tidal circulation patterns. A 2D finite difference numerical model was used to simulate n tidal circulation in the Suyoung Bay in Busan, Korea. CIS, especially the ArcView S/W is used to input the data of the numerical model, and is also used for the visualization of model outputs on the ground in the loosely coupled method. In this paper, an electronic navigational chart (ENC), which provides more accurate information in the ocean and coastal areas than any other digital information, is used as a base map for this integration. With the help of GIS, the integration can support th understanding of oceanographic information.

• 한국지능시스템학회논문지
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• 제9권4호
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• pp.411-419
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• 1999

본 논문은 수정고유벡터법과 퍼지종속관계를 이용한 시스템 수준의 평가방법을 제안한다. 이 모델은 기업에 있어서 시스템의 수준을 평가하기 위하여 설계되었다. 여기서 수정고유벡터법은 두평가그룹에 있어서 각 평가기준의 가중치를 계산하기 위하여 제안되었다. 또한 퍼지종속관계는 일대비교에 의한 편가기준간의 관계를 평가하는데 사용된다. 본 논문에서는 시스템의 현재수준의 평가치를 구하여 시스템의 운영 및 개선에 도움을 주고자 하며 제안하는 방법의 유효성을 환경경영시스템의 평가문제에 대한 사례연구를 통하여 보이고자 한다.

• 한국정밀공학회지
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• 제23권4호
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• pp.44-51
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• 2006

This paper addresses sliding mode control of the anti-lock braking system (ABS) with a disturbance observer for model uncertainties such as vehicle parameter variation, un-modeled dynamics, and external disturbances. By using a nominal vehicle model, a sliding mode controller is designed to achieve a desired wheel slip ratio for ABS control. To compensate the model uncertainties, a disturbance observer is introduced with the help of a transfer function of a hydraulic brake dynamics. A proposed sliding mode controller with a disturbance observer is evaluated through simulations for model uncertainties. The simulation results show that the disturbance observer can enhance performances of sliding mode control for ABS.

• 대한기계학회논문집B
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• 제32권4호
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• pp.317-326
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• 2008

The main purpose of the present study is to perform shape optimizations of transonic compressor blade in order to enhance its performance. In this study, the Latin hypercube sampling of design of experiments and the weighted average surrogate model with the help of a gradient based optimization algorithm are used within design space by the lower and upper limits of each design variable and for finding optimum designs, respectively. 3-D Reynolds-averaged Navier-Stokes solver is used to evaluate the objective functions of adiabatic efficiency and pressure ratio. Six variables from lean and airfoil thickness profile are selected as design variables. The results show that the adiabatic efficiency is enhanced by 1.43% by efficiency optimization while the pressure ratio is increased very small, and pressure ratio is increased by 0.24% by pressure ratio optimization.

• 한국항행학회논문지
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• 제14권5호
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• pp.618-624
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• 2010

본 논문에서는 다중물체를 추적하기 위해서 적합한 것으로 알려진 condensation 알고리즘의 자동 코드 발생기를 연구한 결과를 보인 것이다. 일반적으로 condensation 알고리즘은 일반인이 구현하기 매우 어려워 실제 유비쿼터스 상황인지를 위하여 필요한 기술임에도 불구하고 널리 이용되지 못하고 있다. 본 논문에서는 이 같은 문제점을 개선하기 위하여 시스템 다이나믹스 모델과 측정 모델이 주어지면 요구하는 성능을 만족하는 condensation algorithm이 내장된 필터를 자동으로 만들어주는 MATLAB 코드를 발생하도록 설계하였다. 일단 발생된 MATLAB 코드는 C, C++ 언어 등으로 변환되므로 원하는 소스를 얻을 수 있다.