• 한국시스템다이내믹스연구
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• 제14권1호
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• pp.55-68
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• 2013

It is necessary to evaluate the greenhouse gases (GHGs) reduction policy by central and regional governments to set up the suitable GHG emissions measures. Quantitative, qualitative and synthetic methods have been adopted by previous researches to estimate GHG reduction policy. However, these methods mostly focused on the results of the reduction policy, rather than understanding and fixing the integrated structures of GHG emissions. In this research, System Dynamics(SD) was applied to 1 million green homes program, self-carfree-day system and carbon point program. The results showed that SD analyses could be appliable for the estimation of GHG reduction policy by developing the feedback loops and dynamic simulation model. SD can be consider as a supplementary tool to estimate the GHG reduction policies through the recognition of the structure in complex real system.

• 한국시스템다이내믹스연구
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• 제12권4호
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• pp.63-92
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• 2011

The purpose of this paper is to investigate a possibility of applying multimethodological approach for solving a dilemma. The motivation of this attempt is that the two different approaches, the system dynamics and the theory of constraints, resemble each other in having mental models for describing the target system and using graphic tools for representing those mental models. After a brief discussion on the comparison of the two approaches, a combined method applying to the problem of dilemma is suggested. For an experimental example, the proposed approach is applied to the sales and finance conflict on an inventory issue. The study shows that the suggested approach is able to complement each other's drawbacks. Especially constructing a stock-and-flow model and implementing a computer simulation would be very useful for quantifying the system's behavior which is hardly tracked down when applying the theory of constraints alone.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.219-222
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• 1996

Authors ahve developed ALFLEX simulation program which can implement the flight simulation ad control system design of ALFLEX efficiently by using aerodynamic data provided by NAL/NASDA. Then we have designed and example of flight path and altitude control system of ALFLEX. The philosophy of the design method is explained in detail, and a flight simulation result is shown, which verifies the fine performance of the system.

• 한국시스템다이내믹스연구
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• 제4권2호
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• pp.95-130
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• 2003

The purpose of this study is to find what causes make public projects hold off, going beyond the planned deadline and budget. Using System Dynamics(SD) and their derivative Urban Dynamics(UD) models, it intends to analyze major feedback loops based on VENSIM and to simulate them with STELLA software, all of which are interrelated with various causes of project delay. To prevent or ameliorate project delay, first of all it advises to focus on endogenous delaying factors not exogenous ones. These factors either reinforce or balance certain loops in complex causal structure, In the case example on the Cremation Building Project in Cheongju, Residents’ participation demand make negotiation put off and delayed negotiation reinforces administrative-expediency planning in order to observe a time limit, on the other hand, once building consensus, it increase both the level of planning performance and public trust. In the meantime, the real planning process used to neglect residents opinions and manage public grievance only through compensation, he a result of simulation, visible fruit of negotiation in the initial phase seems to be not satisfactory owing to funds and time consumed, but after reaching an mutual agreement among stakeholders, planning performance is effective and strategic than administrative-expediency planning viewed in both financial and time angle. It proposes to devise specific tools schematizing project implementation. In order to upgrade the quality of project management, it recommends for planners to adopt key concepts based on SD/UD diagrams and causal loops, which would contribute to enriching Planning abbots.

• 한국전산구조공학회논문집
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• 제26권4호
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• pp.247-254
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• 2013

본 논문에서는 해상 시추작업을 위한 heave compensation system의 시뮬레이션 모델을 개발하였다. 우선 시뮬레이션을 위하여, 다물체계 동역학 커널을 개발하였다. 다물체계 동역학 커널은 입력 받은 heave compensation system 시뮬레이션 모델의 운동학적 정보를 이용하여 recursive Newton-Euler formulation 방법을 기반으로 운동방정식을 자동으로 구성하고, 수치적으로 해를 계산하는 기능을 한다. 그리고 해상 시추선에 작용하는 외력을 계산하기 위하여 유체 정역학적 힘과 유체 동역학적 힘을 계산하는 모듈을 개발하였다. 이와 같이 개발한 커널과 모듈들을 적용하여 해상 시추선의 hoisting system 동적거동 해석을 수행하고, 관절에서의 구속력을 계산하였다.

• 동력기계공학회지
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• 제6권4호
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• pp.5-11
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• 2002

• 한국시스템다이내믹스연구
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• 제3권2호
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• pp.5-27
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• 2002

This paper evaluate and compare effectiveness of urban growth management measures in Korea using system dynamics model. Simple urban dynamics model was used to compare urban growth management measures. Since the late 1960s, Korean government has been implementing various urban growth management measures without much success. In the 1960s, factories, universities, and public agencies were strongly encouraged to move out to local areas. During the 1970s, regulations on greenbelt area was adopted to prevent urban sprawl. Besides, regulations to prevent location of population inducing facilities, and promoting dislocation of those facilities were implemented simultaneously. During the 1990, regulations on total number of factories in the metropolitan area, development fees were adopted. These various method of urban management were compared. Simulation results shows that promoting decentralization of population, preventing population immigration, expanding greenbelt area are effectiveness ones compared to controlling total number of population inducing facilities, and preventing construction of new industries. Some implications of the findings were discussed.

• 대한토목학회논문집
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• 제4권3호
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• pp.63-74
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• 1984

System Dynamics는 OR 또는 Industrial Engineering의 수량적(數量的)이고 이론적(理論的)인 분석방법(分析方法) 위에 Management 의사결정(意思決定) 과정(過程) 도입(導入)한 System 적(的) 방법(方法)이다. 그러므로 사회(社會) System의 장래예측(將來豫測)과 아울러 대안(代案)의 검토(檢討) 및 선택방법(選擇方法)으로서는 가장 유효(有効)한 수리적(數理的) 방법(方法)이라고 할 수 있다. 경제기초가설(經濟基礎假說)에 의거(依據)하여 개발(開發)된 도시활동(都市活動)의 생성(生成) Model을 System Dynamics 화(化)하여 토지이용(土地利用)-교통(交通) System Dynamics Model을 구축(構築)하였다. 그리고 대구지성(大邱地城)의 적용례(適用例)에 의(依)하여 Model의 유효성(有効性)을 검토(檢討)하였으며 그 결(結果) 유의(有意)하였다.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.403-411
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• 2005

The bus is regarded as one of the most frequently used public transportation systems, the research and development on driving stability, safety, and convenience for drivers and passengers has tremendously increased in recent days. This paper investigated the design of the bus door mechanism composed of an actuator (or motor) and linkages. The bus door mechanism is divided into many types according to the coupling of the linkages and the driving system. The mathematical models of all types of door mechanism have been constructed for computer simulation. To design the bus door mechanism, we developed a simulation program, which automates the kinematic and dynamic analysis according to the input parameters of each linkage and the driving system. Using this program, we investigated the design parameters that affect the kinematic and dynamic characteristics of the bus door mechanism under various simulation conditions. In addition, simple examples are examined to validate the developed program.

• 한국경영과학회지
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• 제29권2호
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• pp.19-43
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• 2004

This study was motivated by a practical need for estimating the macroeconomic effect of government IT Promotion investment, specifically for micro and small firms. Small firms have been in a disadvantageous position to adopt and utilize new IT compared with medium or large-sized firms. Small firms don't have enough resource to acquire IT in general, therefore private IT companies don't have much incentive to develop IT services and products for small firms. Lack of feasible IT solutions for small firms again restricted active IT adoption of small firms. Government recognized the vicious cycle, therefore decided to promote private IT companies to develop IT services and products for small firms's. Our main concern was to identify a relevant government supporting Policy, especially in the amount and the period. To do this, we first constructed a system dynamics simulation model to Investigate important factors and causal relationships among them. Simulation results showed 2.19% of GDP contribution and 0.16% of employment contribution in max from small firms' IT adoption. Also we could find that investing proper amount for a short period would be for better than maintaining Investing small amount for a long period.