• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1999년도 추계공동학술대회 논문집:21세기지식경영과 정보기술
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• pp.759-768
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• 1999

In this paper, we developed a simulation model of a car parts assembly line to improve the system performance such as worker's utilization balancing, productivity. This simulation model has been developed using QUEST, a true 3D discrete event simulation pakcage that is designed for modeling and analysis of manufacturing systems. We have suggested the results obtained to improve the system performances of an existing production line.

• International Journal of Automotive Technology
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• 제6권3호
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• pp.277-283
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• 2005

Formability simulation of automotive panels at early design phases can reduce product and tooling development time and cost. However, for the simulation to be effective in leading the design process, fast and reliable results should be achieved with limited design definition and minimum modeling effort. In this paper, nonlinear finite element analysis is used to develop an automated process for the formability simulation of automotive body panels at early design phases. Due to the limited design definition at early design phases, the automated simulation process is based on the plane strain analysis for selected number of typical sections along the panel. Therefore, an entire panel can be analyzed with few sections. The state of plane strain can be easily induced, during simulation through symmetry and applied boundary conditions that simplify the modeling process. To study the reliability and effectiveness of the developed simulation process, the analytical results are compared with measured results of production automotive body side panels. The comparison demonstrates that the developed simulation process is reliable and can be effective for analyzing sheet metal formability, in early vehicle development phases.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.216-218
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• 2002

This study is the modeling of resistive type SFCLs. There was numerical modeling and simulation using EMTP in the conventional modeling of SFCL. The numerical modeling was presented an analysis of numerical characteristic of SFCL. And the modeling using EMTP was made up of the study for setting method of specific parameters of a SFCL. This paper proposes the model of resistive type superconducting fault current limiter using EMTDC(Electromagnetic transients for DC analysis program). The simulation schemes that can be applied to the utility network readily and cheaply under various conditions considering the sort of fault, the capacity of systems as well are strongly expected and emphasized among researchers.

• 한국정밀공학회지
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• 제20권6호
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• pp.160-166
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• 2003

Interest in advanced vehicles results in correspondingly increased interest in modeling and simulation of the dynamic behavior of Maglev-type vehicle systems. DADS is a program especially suited for the analysis of multibody mechanical systems. This paper demonstrates the application of DADS to the dynamic modeling and simulation of such advanced vehicles. A brief description is made of the modeling requirements of magnetically levitated systems, along with a summary of some of the related capabilities of DADS. As a case study, an analysis of a vehicle based on the UTM01 system is presented. This paper shows that the presented modeling technique is applicable to the dynamic characteristics evaluation and control law design of Maglev- type vehicles.

• 한국시뮬레이션학회논문지
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• 제25권4호
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• pp.53-63
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• 2016

본 연구는 컴퓨터 해석프로그램 SimulationX로 압력 유량 제어형 사판식 피스톤 펌프의 해석모델을 개발하여 설계의 타당성을 검증하는 것을 다룬다. 설계도면의 제원을 바탕으로 해석모델을 개발하게 되면 프로토타입 제작 이전에 설계의 유효성을 미리 판단할 수 있고 이로 인해 제작상의 반복적 오류를 범하지 않기 때문에 개발비 절감의 효과를 가져올 수 있다. 해석모델 개발의 진행순서는 다음과 같다. 먼저 동역학적 요소가 포함된 밸브, 회전부 등의 각 부품의 구조를 분석하고 도면의 제원을 반영하여 단품 모델링을 한다. 각각의 해석모델을 조합하여 펌프 어셈블리 모델링을 하고 이것이 설계의도에 맞게 부하조건에 따른 압력 유량제어 기능을 원활히 수행할 수 있는지 파악한다. 모델링 절차의 마지막에는 예상했던 메카니즘대로 부품들이 움직이는 모습을 보여줌으로서 설계의 타당성을 검증한다.

• 한국소음진동공학회논문집
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• 제18권4호
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• pp.465-472
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• 2008

An automotive windshield wiper system is modeled mainly for vibration analysis purpose. The model is composed of solid links, ideal joints, imperfect joints to simulate unavoidable manufacturing defects and bushings having stiffness, contact between a wiper blade and a wind screen glass, friction, a spring and an actuator. Main stream of wiper dynamics analysis has been obtaining a closed form of system of equations using Newton's or Lagrange's formula and doing a numerical simulation study to understand and predict the behavior of it. However, the modeling process is complex since a wiper system is of multibody and a contact problem occurs. When imperfection, such as dead zone of a joint and stiffness of a rubber bushing, should be included, the added complexity makes the modeling difficult. Since the imperfection is understood as main cause of problematic vibration, the dynamics model of a wiper system aiming vibration analysis should include such unavoidable manufacturing defects in the model. An open form of dynamic model of a automotive windshield wiper system with imperfect joints using a commercial software is obtained and a simulation analyssis is conducted for vibration reduction study.

• 한국CDE학회논문집
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• 제20권3호
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• pp.221-229
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• 2015

M&S (Modeling & Simulation) based design is widely accepted for the development of the future weapon system with better performance in a cheaper and faster way. Integrated simulation environment (ISE) is needed for the M&S based design. On the ISE, system engineers can not only verify design options but also validate system requirements. In this paper, we propose architectural models of the integrated simulation environment (ISE) which incorporates mission effectiveness M&S (Modeling & Simulation), system performance M&S, the optimization model of integrated performances, digital mockup and virtual prototype. The ISE architectural models may be used to implement the ISE for the development of the future unmanned ground combat vehicle.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.410-419
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• 2018

Purpose: CLIMEX, a species distribution modeling tool, includes various types of parameters representing climatic conditions; the estimation of these parameters directly determines the model accuracy. In this study, we investigated the sensitivity of parameters for the climatic suitability calculated by CLIMEX for Metcalfa pruinosa in South Korea. Methods: We first changed 12 parameters and identified the three significant parameters that considerably affected the CLIMEX simulation response. Results: The result indicated that the simulation was highly sensitive to changes in lower optimal temperatures, lower soil moisture thresholds, and cold stress accumulation rate based on the sensitivity index, suggesting that these were the fundamental parameters to be used for fitting the simulation into the actual distribution. Conclusion: Sensitivity analysis is effective for estimating parameter values, and selecting the most important parameters for improving model accuracy.

• 전기학회논문지
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• 제58권10호
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• pp.2028-2037
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• 2009

This paper presents the simulator for dynamic modeling of a MT(micro turbine) during start-up period. The simulator is implemented by modeling a dynamic power of main components of a MT including compressor, combustor and turbine. A modeling for a MT under steady state operation can be accurately built from thermodynamics analysis. But dynamic modeling during start-up period is very difficult because efficiency of main components is very low and the designed value has big error and nonlinear characteristics during start-up. In this paper, new method without using thermodynamics analysis during start-up is proposed for the simulator. The power models of main components are derived from analysis of the experimental operation data by test motoring using a electric starter under constant power output. The simulator is developed using MATLAB/Simulink. For constant power output control, sensorless vector inverter is designed and algorithms for starting from stall and method for controling a output power are proposed. The performance of developed simulator is verified by comparing experimental and simulation start-up results.

• 한국시뮬레이션학회논문지
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• 제19권4호
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• pp.261-270
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• 2010

무기체계 효과도 분석을 위한 통합 시뮬레이션 엔진은 모델의 개발부터 시뮬레이션 수행 및 분석에 이르는 모델링 및 시뮬레이션 전 단계에 걸쳐 도구와 서비스 및 인터페이스를 제공해야 한다. 다양한 국방 통합 시뮬레이션 엔진을 제공하고 있는 국외와는 달리, 국내에서는 자체적인 분산 실시간 모의체계 엔진에 대한 연구 및 개발이 미흡하여 무기체계 M&S(Modeling and Simulation) 활동 시 유사 업무가 반복되고 있는 실정이다. 본 논문에서는 국외의 기 개발된 국방 M&S 모의엔진의 서비스를 비교 분석하여 무기체계 효과도 분석을 지원하기 위한 통합 시뮬레이션 엔진인 OpenSIM(Open Simulation Engine for Interoperable Model)을 소개하고, OpenSIM에서 제공하는 서비스의 범위 및 내용을 정의한다. 정의된 서비스는 모델링 실행 분석에서 공통적으로 많이 사용되는 클래스, 함수 및 데이터 등을 구현하여 프로그래밍의 복잡도를 감소시킬 수 있다.