• Management Science and Financial Engineering
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• 제19권1호
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• pp.37-41
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• 2013

This study presents an application of stochastic model for limit order book (LOB) dynamics to Korean Stock Index Futures (KOSPI 200 Futures). Since KOSPI 200 futures market is widely known as one of the most liquid markets in the world, direct application of an existing model is hardly possible. Therefore, we modified an existing model to successfully model and predict the dynamics of extremely liquid KOSPI 200 futures market.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.669-674
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• 1989

Robot manipulators are highly coupled nonlinear systems and their motions are influenced by uncertain dynamics. In this paper a design methodology which is called model feedback control system or plant model control scheme is presented for the purpose of reducing the influence of the uncertain dynamics. This control system is applied to the trajectly control of the directly drived robot. Theoretically and experimentally performances resulting from use of this control scheme show that the influences of the uncertain dynamics are reduced obviously.

• 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.

• 한국산업보건학회지
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• 제8권2호
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• pp.163-177
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• 1998

Computational Fluid Dynamics(CFD) was applied to predict air flow around the hoods : circular hoods, square hoods, and push-pull hoods. A commercially available CFD software, CFD-ACE(Ver. 4.0), was tested, which is based on the finite volume method using the ${\kappa}-{\varepsilon}$ turbulence model. Numerical results were compared with the experimental, analytical and numerical results from other studies. CFD solutions showed an excellent agreement with the previous experimental and numerical results. It is promising that CFD techniques could be applied on the variety of complex problems in the industrial ventilation engineering.

• 대한전자공학회논문지
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• 제26권11호
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• pp.1759-1769
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• 1989

This paper presents the development of a simulator for an industrial robot. The simulator is characterized by a fully integrated dynamic model and a hardware oriented control scheme. The dynamic model includes the actuator dynamics as well as the manipulator dynamics to integrate the entire dynamics of the robot system. On the other hand, the control scheme is oriented as a hardware structure which is usually implemented in the industrial robot. That is to say, a conventional PI control law is used to regulate the position, the speed, and the current. A Pulse Wave Modulation (PWM)generator modulates the supplied voltage to the actuator. Since the simulator is consistent with the industrial robot system, it provides the essential design concepts for the development process of the robot. In practice, the simulator is applied to the SCARA robot which has been developed in GSIS. Here, it investigates the characteristics and performance of the robot with changing design parameters. Thus, the investigation furnishes criteria for the selection of acfuator, control gain, trajectory planning, etc.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.114-114
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• 2003

Fiber bundles output from a draft operation have linear density irregularity. This study is dealing with modeling the dynamics of fiber bundle during roll drafting based on continuity, momentum balance, and a constitutive assumption. The simulation results from this model are compared with experimental results and analyzed by applying the concept of the Describing Function(DF). It can be confirmed that the simulation results agree well with experiments in a steady state, if the model parameters are good adjusted.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제22권3호
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• pp.179-199
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• 2018

The paper explores a tri-trophic food chain model with density dependent mortality of intermediate predator. To analyze this aspect, we have worked out the local stability of different equilibrium points. We have also derived the conditions for global stability of interior equilibrium point and conditions for persistence of model system. To observe the global behaviour of the system, we performed extensive numerical simulations. Our simulation results reveal that chaotic dynamics is produced for increasing value of half-saturation constant. We have also observed trajectory motions around different equilibrium points. It is noticed that chaotic dynamics has been controlled by increasing value of density dependent mortality parameter. So, we conclude that the density dependent mortality parameter can be used to control chaotic dynamics. We also applied basic tools of nonlinear dynamics such as Poincare section and Lyapunov exponent to investigate chaotic behaviour of the system.

• 드라이브 ㆍ 컨트롤
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• 제21권2호
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• pp.44-52
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• 2024

In this study, we predicted PTO power requirements based on torque predicted by the discrete element method and the multi-body dynamics coupling method. Six different scenarios were simulated to predict PTO power requirements in different soil conditions. The first scenario was a tillage operation on cohesionless soil, and the field was modeled using the Hertz-Mindlin contact model. In the second through sixth scenarios, tillage operations were performed on viscous soils, and the field was represented by the Hertz-Mindlin + JKR model for cohesion. To check the influence of surface energy, a parameter to reproduce cohesion, on the power requirement, a simple regression analysis was performed. The significance and appropriateness of the regression model were checked and found to be acceptable. The study findings are expected to be used in design optimization studies of agricultural machinery by predicting power requirements using the discrete element method and the multi-body dynamics coupling method and analyzing the effect of soil cohesion on the power requirement.

• 한국경영과학회지
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• 제3권2호
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• pp.75-90
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• 1978

The objective of this paper is to demonstrate how System Dynamics Approach may be used to develop new ways of analyzing and projecting manpower requirements and resources. For this purpose, a System Dynamics Model is presented as an example. An examination of the model will show that a System Dynamics modeling approach is an innovative and useful tool for manpower policy analysis and planning. Second, with minor modifications, the model may be used for manpower policy analysis and planning for any skilled personnel in Korea. For example, a similar model nay be built for engineers to analyze the effects of alternative policies about engineering education, sur as the number of available places in the various institutions of training, scholarships and loans, and the duration of training. An engineer's model may also be used to make the projections of the supply and requirements of engineers in the future according to various alternative assumptions where each assumption represents a policy option.

• 한국시스템다이내믹스연구
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• 제10권1호
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• pp.61-76
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• 2009

We try to use system dynamics to forecast the demand/supply and price, also transportation fare for iron ore. Iron ore is very important mineral resource for industrial production. The structure for this system dynamics shows non-linear pattern and we anticipated the system dynamic method will catch this non-linear reality better than the regression analysis. Our model is calibrated and tested for the past 6 year monthly data (2003-2008) and used for next 6 year monthly data(2008-2013) forecasting. The test results show that our system dynamics approach fits the real data with higher accuracy than the regression one. And we have run the simulations for scenarios made by possible future changes in demand or supply and fare related variables. This simulations imply some meaningful price and fare change patterns.