• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1994년도 춘계초청 강연회 및 임시총회
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• pp.0.1-0
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• 1994

• 한국시뮬레이션학회논문지
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• 제11권4호
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• pp.1-14
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• 2002

This paper presents bounding space(BS) management for real-time visual simulation when using GK-DEVS models. Since GK-DEVS, extended from DEVS formalism, has information of 3D geometry and 3D hierarchical structure, we employs three types of bounding spaces: BS of its own shape, BS of its children GK-DEVS, and total BS. In addition to next-event scheduling functionality of previous GK-Simulator, its abstract simulation algorithms is extended to manage the three types of BSs so that BSs can be utilized in the rendering process of a renderer, so called GK-Renderer, We have implemented the method and evaluated it with an automated manufacturing system. In the case study, the proposed BSs management method showed about 2 times improvement in terms of rendering process speed.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.74-79
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• 1996

This paper describes a methodology for the development of models of discrete event system(DES). The methodology is based on transformation of continuous state space into discrete one to homomorphically represent dynamics of continuous processes in discrete events. This paper proposes a formal structure which can couple DES models within a framework. The structure employs the DEVS formalism for the DES models. The proposed formal structure has been applied to develop a DEVS model for the human cardiovascular system. For this, the cardiac cycle is partitioned into a set of phases based on events identified through VisSim simulation in the CS of the electrical analog model. VisSim is the simulation tool of visual environment for developing continuous, discrete, and hybrid system models and performing dynamic simulation. For each phase, a CS of the electrical analog model for the cardiovascular system has been simulated by VisSim 2.0. To validate this model, first develop the DEVS model, then simulate the model in the DEVSIM++ environment. It has same simulation results for the data obtained from the CS simulation using VisSim. The comparison shows that the DEVS model represents dynamics of the human heart system at each phase of cardiac cycle.

• 한국군사과학기술학회지
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• 제17권2호
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• pp.235-247
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• 2014

Based on two dimensional model partition method proposed in Part 1, Part 2 provides detailed model specification and implementation. To mathematically delineate a model's behaviors and interactions among them, we extend the DEVS (Discrete Event Systems Specification) formalism and newly propose CE-DEVS (Combat Entity-DEVS) for an upper abstraction sub-model of a combat entity model. The proposed CE-DEVS additionally define two sets and one function to reflect essential semantics for the model's behaviors explicitly. These definitions enable us to understand and represent the model's behaviors easily since they eliminate differences of meaning between real-world expressions and model specifications. For model implementation, upper abstraction sub-models are implemented with DEVSim++, while the lower sub-models are realized using the C++ language. With the use of overall modeling techniques proposed in Part 1 and 2, we can conduct constructive simulation and assess factors about combat logics as well as battle field functions of the next-generation combat entity, minimizing additional modeling efforts. From the anti-torpedo warfare experiment, we can gain interesting experimental results regarding engagement situations employing developing weapons and their tactics. Finally, we expect that this work will serve an immediate application for various engagement warfare.

• 한국시뮬레이션학회논문지
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• 제8권1호
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• pp.113-138
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• 1999

Driven by the explosive expansion and acceptance of the Internet and its multimedia front-end, the Web, a new generation of the modeling and simulation tools have come up with the name of Web-Based Simulation (WBS). Most of WBS libraries inherit its powerful advantages from Java. However, there are cases where explicit specification of models or interface objects is more desirable than the black-box programs. This paper presents an XML-based DEVS (Discrete Event System Specification) markup language for sharing simulation models on the Web. DEVS provides a system-theoretic formalism for the language while XML supports platform-independent data access. This paper focuses on the design of such a language.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.90-99
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• 2007

The DEVS formalism has the well-defined relationship between its model and simulator. However, it does not define the connection between its model and experimental frame needed when a simulator's implemented with it. So, in most DEVS based simulators, the modules of the two parts are tangled, so that changing and reusing them is not easy. This paper proposes a method to improve the changeability of the experimental frame and the reusability of the model by modularizing the two parts using the AOP technology. I applied the new method to a real project, and the result shows that it improves the two qualities effectively than before.

• 제어로봇시스템학회논문지
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• 제9권4호
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• pp.310-319
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• 2003

As the importance and the need for network security are increased, many organizations use the various security systems. They enable to construct the consistent integrated security environment by sharing the network vulnerable information among IDS (Intrusion Detection System), firewall and vulnerable scanner. The multiple IDSes coordinate by sharing attacker's information for the effective detection of the intrusion is the effective method for improving the intrusion detection performance. The system which uses BBA (Blackboard Architecture) for the information sharing can be easily expanded by adding new agents and increasing the number of BB (Blackboard) levels. Moreover the subdivided levels of blackboard enhance the sensitivity of the intrusion detection. For the simulation, security models are constructed based on the DEVS (Discrete Event system Specification) formalism. The intrusion detection agent uses the ES (Expert System). The intrusion detection system detects the intrusions using the blackboard and the firewall responses to these detection information.

• 한국시뮬레이션학회논문지
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• 제4권1호
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• pp.13-24
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• 1995

In general, simulation and analytic method are used for real system analysis. However, or date, there has been only the theoretical works on each approach. Therefore it is required that we study on the relationship between each approaches to obtain more reliable and correct system analysis results. In this paper, using SPN(Stochasitc Petri Net) formalism, we propose the method of output prediction of the DEVS(Discrete Event system Specification) simulation. For this we suggest a transformation algorithm which transform SPN form DEVS formalism based on the event scheduling world view and a verification algorithm for it. We then show an example to apply it to the real system, such that the Grocery Store System.

• 한국시뮬레이션학회논문지
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• 제11권1호
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• pp.11-22
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• 2002

In this paper, a RAID system is modeled and simulated by using the DEVS formalism. The RAID system interacts with a host system by using the high-speed Fibre channel protocol and stores data in an array of IDE disks. The DAVS formalism specifies discrete event systems in a hierarchical, modular manner. The RAID system model is composed of three units: primary-PCI unit, secondary-PCI unit and MCU unit. The primary-PCI unit interfaces with the host system and I/O data caches. The secondary-PCI unit includes disks. The MCU unit controls overall system. The control algorithm of MCU and PCI transactions are analyzed and modeled, From the analysis of simulation events, we can conclude that the proposed model satisfies given requirements.

• 한국시뮬레이션학회논문지
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• 제11권4호
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• pp.91-105
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• 2002

The attackers on Internet-connected systems we are seeing today are more serious and technically complex than those in the past. So it is beyond the scope of amy one system to deal with the intrusions. That the multiple IDSes (Intrusion Detection System) coordinate by sharing attacker's information for the effective detection of the intrusion is the effective method for improving the intrusion detection performance. The system which uses BBA (BlackBoard Architecture) for the information sharing can be easily expanded by adding new agents and increasing the number of BB (BlackBoard) levels. Moreover the subdivided levels of blackboard enhance the sensitivity of the intrusion detection. For the simulation, security models are constructed based on the DEVS (Discrete EVent system Specification) formalism. The intrusion detection agent uses the ES (Expert System). The intrusion detection system detects the intrusions using the blackboard and the firewall responses these detection information.