• 한국시뮬레이션학회논문지
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• 제10권4호
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• pp.51-64
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• 2001

It is quite necessary that an organization's information network should be equipped with a proper security system based on its scale and importance. One of the effective methods is to use the simulation model for deciding which security policy and mechanism is appropriate for the complex network. Our goal is to build a foundation of knowledge-based modeling and simulation environment for the network security. With this environment, users can construct the abstracted model of security mechanisms, apply various security policies, and quantitatively analyze their security performance against possible attacks. In this study, we considered security domain from several points of view and implemented the models based on a systematic modeling approach. We enabled the model to include knowledge in modular fashion and provided well-defined guidelines for transforming security policy to concrete rule set.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1992년도 제2회 정기총회 및 추계학술 발표회 발표논문 초록
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• pp.6-6
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• 1992

This work deals with nonlinear least squares method for estimating unknown universial constants C in a computer simulation code real experimental data(or database) and computer simulation data. The best linear unbiased predictor based on a spatial statistical model is fitted from the computer simulation data. Then nonlinear least squares estimation method is applied to the real data using the fitted prediction model(or simulation predictor) as if it were the true simulation model. An application to the computational nuclear fusion device is presented.

• 한국산업융합학회 논문집
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• 제4권3호
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• pp.329-337
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• 2001

This simulator is developed for the analysis of a MOSFET based on Thermally Coupled Energy Transport Model(TCETM). The simulator has the ability to calculate not only stationary characteristics but also non - stationary characteristics of a MOSFET. It solves basic semiconductor devices equations including Possion equation, current continuity equations for electrons and holes, energy balance equation for electrons and heat flow equation, using finite difference method. The conventional semiconductor device simulation technique, based on the Drift-Diffusion Model (DDM), neglects the thermal and other energy-related properties of a miniaturized device. I, therefore, developed a simulator based on the Thermally Coupled Energy Transport Model (TCETM) which treats not only steady-state but also transient phenomena of such a small-size MOSFET. In particular, the present paper investigates the breakdown characteristics in transient conditions. As a result, we found that the breakdown voltage has been largely underestimated by the DDM in transient conditions.

• 한국시뮬레이션학회논문지
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• 제3권2호
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• pp.69-76
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• 1994

Traditionally, simulation-based learning games which are known as flight-simulators have been constructed as a black-box game. Within a black-box game, game-players can view and modify only a part of model parameters. Game-players cannot change the structure of a simulation model. In a black-box game, game-players cannot understand and learn the system structure which is responsible for the system behavior. In this paper, the multi-tasking at the level of operating systems is exploited to enhance the transparency of simulation-based learning game. The white-box game or transparent-box game allows game-players ot view and modify the model structure. The multi-tasking solution for white-box learning game is implemented with Smalltalk language on MS-/windows operating system.

• 한국멀티미디어학회논문지
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• 제18권3호
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• pp.349-358
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• 2015

Simulating color appearance of makeup effect is an important issue in computer graphics as well as cosmetic industry. Most of previous works on makeup simulation are simple color blending to mimic the cosmetic effects. Some of previous works employed Kubelka-Munk model to accurately simulate the layering effect of cosmetics. However, the simulation limited on single point, and the rest of area are still computed by simple color blending utilizing the color of the single point simulation. This paper presents an image-based method to compute the color appearance effect of makeup application using per-pixel Kubelka-Munk model. Unlike the previous methods, it is possible to compute per-pixel application thickness as well as optical property of cosmetics. The computed thickness pattern can be used in makeup simulation for a more realistic makeup simulation.

• 품질경영학회지
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• 제42권4호
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• pp.591-606
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• 2014

Purpose: The purpose of this study is to design an experimental simulation model for evaluating the UGV(Unmanned Ground Vehicle) effectiveness in a small unit combat scenario. Methods: We design and build a simulation model to evaluate the combat effectiveness of UGV in a small unit combat scenario. In order to build a simulation model, we used AnyLogic software tool which has functional advantages to describe agent-based simulation model. As for the combat scenario, we applied the typical engagement of mechanized unit equal or lower than battalion level. Analysis process follows the three phases. 1) Design an agent based conceptual medel in a small unit combat scenario. 2) Build a simulation medel using AnyLogic tool. 3) Analyze the simulation results and evaluate the UGV effectiveness. Results: The UGV effectiveness was measured and presented as a numeric values. Those numeric values were represented as a MOE(Measure of Effectiveness) which was the blue survival ratio. Conclusion: We developed an agent based simulation model which can provide a pattern of change how UGV effectiveness varied depending upon the number of UGV in a small unit combat scenario. We also found that the UGV effectiveness grows in the given scenario as the number of UGV increases.

• 한국시뮬레이션학회논문지
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• 제19권4호
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• pp.169-178
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• 2010

행위자 기반 시뮬레이션은 시스템을 구성하고 있는 개체들이 자율적인 판단과 기억에 의해 상호 영향을 주면서 주어진 환경에 대응할 때 일정 시간이 경과한 후 시스템에 어떠한 현상이 발생하는가를 관찰하기 위하여 사용된다. 본 논문에서는 팀 결성의 행태를 분석하기 위한 행위자 기반 시뮬레이션 모형을 개발하였다. 팀의 결성은 팀 구성원 개개인의 선택과 판단에 의하지만 어느 한 개인의 일방적인 의사에 의해 이루어지기 보다는 여러 구성원의 상호 관계에 의한 것이라는 점, 그리고 이렇게 구성된 팀의 성취도는 경험이 반복될수록 변화한다는 점 등이 생태학적인 접근법을 가능하게 한다. 개발한 모형은 Netlogo 4.1으로 구현하였고 모의시험을 통해 검증하였다. 모의시험의 결과는 행위자 기반 시뮬레이션의 특성인 규칙의 적용 및 판단, 기억 및 진화의 속성을 잘 묘사할 수 있음을 보여주었다. 개발한 모형을 발전시킴으로써 팀 결성의 다양한 생태학적 분석에 적용이 가능하다.

• 한국CDE학회논문집
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• 제18권3호
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• pp.224-233
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• 2013

For the scheduling and the job assignment of the ship hull production design which is a process-based work, we suggest the simulation-based scheduling using the discrete-event-based business process simulation. First, we analyze the ship hull production design process from the perspective of a job assignment to make it into the simulation model using DEVS (Discrete Event System Specification) which is the representative modeling method for a discrete-event simulation. Based on the APIs of the open-source discrete-event simulation engine, we implement the simulation using the Groovy script. We develop the scenario generator in which the user defines detail information of the construction drawing and its member blocks, and design engineers information, and the various setting for the simulation including the job assignment strategy. We use the XML files from this scenario generator as inputs of simulation so that we can get simulation result in forms of Gantt chart without changes of the simulation model.

• 물과 미래
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• 제13권4호
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• pp.41-50
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• 1980

본 연구는 Gamma 분포의 이론적 검토와 이의 수공학에의 적용, 즉 Gamma 분포의 적합성 및 Gamma 모델에 의한 하천유량의 Simulation에 대한 연구와 검토를 행하는데 그 목적을 두고 있다. 분석에 있어서 우리나라 주요하천(낙동강, 한강 및 금강)의 월유량자료를 사용하였으며 분석을 간단하게 하기 위하여 자료를 Modular coefficient로 변환시켰다. 먼저 이변수 Gamma 분포형에 대한 월류량에의 적합성을 검정하였으며 이로부터 Gamma 분포형과 Monto Carlo 기법을 기초로 한 Gamma 모델에 의하여 월류량의 Simulation을 행하였다. 그 결과 기록치와 매우 근접한 Simulation 자료를 얻을 수 있었다.

• Smart Structures and Systems
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• 제14권6호
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• pp.1081-1103
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• 2014

Real-time hybrid simulation (RTHS) has emerged as an important tool for testing large and complex structures with a focus on rate-dependent specimen behavior. Due to the real-time constraints, accurate dynamic control of servo-hydraulic actuators is required. These actuators are necessary to realize the desired displacements of the specimen, however they introduce unwanted dynamics into the RTHS loop. Model-based actuator control strategies are based on linearized models of the servo-hydraulic system, where the controller is taken as the model inverse to effectively cancel out the servo-hydraulic dynamics (i.e., model-based feedforward control). An accurate model of a servo-hydraulic system generally contains more poles than zeros, leading to an improper inverse (i.e., more zeros than poles). Rather than introduce additional poles to create a proper inverse controller, the higher order derivatives necessary for implementing the improper inverse can be calculated from available information. The backward-difference method is proposed as an alternative to discretize an improper continuous time model for use as a feedforward controller in RTHS. This method is flexible in that derivatives of any order can be explicitly calculated such that controllers can be developed for models of any order. Using model-based feedforward control with the backward-difference method, accurate actuator control and stable RTHS are demonstrated using a nine-story steel building model implemented with an MR damper.