• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.15-22
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• 2019

Simulation methods are being studied for various service models that can be used in industries as the development of web technology. DEVS is being used as a tool to simulate through scenarios using various information. In addition, DEVS/WS integrates web-based DEVS models through a distributed computing environment and can be used as tools for high-performance computing and data distribution. This paper describes a method for simulating an intelligent transportation system in DEVS/WS environment. This paper propose dynamic interest management model(DIMM) applied the genetic algorithm, manage efficiently road information of moving node. And, this paper evaluates performance of the dynamic interest management model in comparing to the none interest management model(NIMM). The transmitted messages and simulation time of the DIMM is saved than that of the NIMM.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.217-226
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• 2006

To maintain competitiveness in the modern automotive market, it is important to carry out process planning concurrently with new car development processes. Process planners need to make decisions concurrently and collaboratively in order to reduce manufacturing preparation time for developing a new car. Automated generation of a simulation model by using the integrated process plan database can reduce time consumed for carrying out a simulation and allow a consistent model to be used throughout. In this research, we developed a web-based system for concurrent and collaborative process planning and flow analysis for an automotive general assembly using web, database, and simulation technology. A single integrated database is designed to automatically generate simulation models from process plans without having to rework the data. This system enables process planners to evaluate their decisions quickly, considering various factors, and easily share their opinions with others. By using this collaborative system, time and cost put into the assembly process planning can be reduced and the reliability of the process plan would be improved.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.2
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• pp.184-190
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• 2008

This paper describes a message model based on XML (eXtensible Markup Language) to present real-time data from sensors and instruments at manufacturing processes for web service. HTML (Hyper Text Markup Language) is inadequate for describing real-time data from process control plants while it is suitable for displaying non-real-time multimedia data on web. For XML-based web service of process data, XML format for the data presentation was proposed after investigating data of various instruments at steel-making plants. Considering transmission delay inevitably caused from increased message length and processing delay from transformation of raw data into defined format, which was critical for operation of a real-time system, its performance was evaluated by simulation. In the simulation, we assumed two implementation models for conducting the transformation function. In one model, transformation was done at an SCC (Supervisory Control Computer) after receiving real-time data from instruments. In the other model, transformation had been carried out at instruments before the data were transmitted to the SCC. Various tests had been conducted under different conditions of offered loads and data lengths and their results were described.

• Journal of the Korea Society for Simulation
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• v.19 no.1
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• pp.33-39
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• 2010

As future warfare becomes network-centric, war-game simulators require high interoperability between networked forces and dynamic reconfiguration in accordance with war events. In this paper, we propose an event-driven methodology to develop dynamic war-game simulations. Federates are developed by event-driven web services. The event-driven web services consistently sense war events and response them only if they are interested. By the sense-and-response mechanism and asynchronous event processing, we are able to save simulation time. An Anti-Surface-Warfare simulator is constructed to demonstrate the methodology and suggests that event-driven web services are efficient to model and simulate warfare where numerous events are generated from hardware systems and people dispersed on the network.

• The KIPS Transactions:PartA
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• v.8A no.3
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• pp.201-208
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• 2001

Explosive growth of the Web and the non-uniform characteristics of client requests result in the performance degradation of Web servers, and server cache has been recognized as the solution. We analyzed Web server accessing characteristics-repetition, size, and locality of access. Based on the result, we analyzed the cache removal policies and proposed a prefetch strategy to improve the hit ratio of server caches. In addition, through the trace-driven simulation based on the traces from real Web sites, we showed the performance improvement by our proposal.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.05a
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• pp.88-95
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• 2001

VR(Virtual Reality)의 개념이 제조공학 분야로 확대 적용되면서 설계분야에서의 가상조형 (Virtual Prototyping), 제조분야에서의 가상제조시스템(Virtual Manufacturing System)이라는 새로운 형태의 제조 시스템 및 설계기술이 차세대 제조기술로서 발전해 오고있으며 이런 가상제조방법(Virtual Manufacturing)은 컴퓨터를 이용하며 생산과정에서 제품뿐만이 아니라 유한요소해석을 유용하여, 공정까지도 모의실험을 하며 생산성(manufacturability), 최종 형태(final shape), 잔류 응력(residual stress), 제품 수명 주기(life-cycle)등과 같은 요소들의 최적화 정보를 제공하게 된다. 본 연구에서는 이러한 가상제조방법을 구현하기 위한 기초적 단계로서 가상단조기계를 가상현실기법을 이용하여 모델링하고 Java를 이용하여 모델링된 단조기계를 제어하고 제조되는 단조물에 대한 내부 응력 및 형태변환을 유한 요소법을 이용하여 분석하고 분석된 단조물의 자료를 WEB상을 통하여 닥 수 있게 유한 요소 해석결과를 VRML언어로 변환하는 작업을 수행하였다.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.655-662
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• 2000

According to the development of internet with Web, WBI has greatly influence on the present educational society. However, it is difficutly to design the web of the dynamic motions of graphics or animation using general programming technique based on high or low level language. Recently, Mecromedia Company supported a tool that is called Authoware which is the leading visual rich-media authoring solution for creating Web and online learning applications, to solve the problem easily. In the paper, using the the Authoware we tried to develop a web page about tidal variations due to sea level change and intertidal zone variations using the Authorware 5.1. To do this, we used the ocean survey data of Iho beach and the tidal level data based on Tidal Tables of Cheju harbor. The results showed that the Authorware was very useful to construct the simulation of tidal phenomena on web. Therefore, the Authorware can be applied to the simulation related with animation and dynamic motions for the other WBI objective.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.77-86
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• 2007

Web services are considered as the critical component in the business plans of corporations as they offers the potential for creating highly dynamic and versatile distributed applications that span across business boundaries. Web Service Orchestration studies composition of already-existing web services to create new value-added services. The composite web services could be executed in a centralized or peer-to-peer(P2P) orchestration model. Compared with centralized-orchestration model, the P2P-based orchestration model provides better scalability, reliability, and performance for the overall services. However, recent P2P-orchestration solutions have limitation in supporting complex workflow patterns. Therefore, they could not effectively handle sophisticated business workflow, which contains complex workflow patterns. In this paper, we propose the WORKGLOW system, which can deal with complex workflow patterns while it is able to perform composite services in P2P orchestration manner. Comparing with centralized orchestration systems, the WORKGLOW brings up more business logic advantages, better performance, and higher flexibility with only a little overhead.

• Steel and Composite Structures
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• v.25 no.6
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• pp.671-684
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• 2017

Elastic-plastic shear buckling behaviors of the web-post in a Castellated Steel Beam (CSB) with hexagonal web openings under vertical shear force were investigated further using Finite Element Model (FEM) based on a sub-model, which took the upper part of the web-post under horizontal shear force to represent the whole web-post under vertical shear force. A simplified design method for the web-post elastic-plastic shear buckling strength was proposed based on simulation results of the sub-model. Proper boundary conditions were applied to the sub-model to assure that its behaviors were identical to those of the whole web-post. The equation to calculate the thin plate elastic shear buckling strength was adopted as the basic form to build the design equation for elastic-plastic buckling strength of the sub-model. Parameters that might affect the elastic-plastic shear buckling strength of the whole web-post were studied. After obtaining the vertical shear buckling strength of a sub-model through FEM, the shear buckling coefficient k can be obtained through the back analysis. A practical calculation method for k was proposed through curving fitting the parameter study results. The elastic-plastic shear buckling strength of the web-post calculated using the proposed shear buckling coefficient k agreed well with that obtained from the FEM and test results. And it was more precise than those obtained from EC3 based on the strut model.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1716-1721
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• 2014

In this paper, a study on automation method for the circuit/EM (Electro-Magnetic) simulation is carried out to analyze effectively the SI/PI (Signal Integrity/Power Integrity) issues which occur on circuits and/or PCBs (Printed Circuit Boards). For the automation of the circuit/EM simulation, algorithms performing each process of the SI/PI analysis automatically (such as ports setup, circuit definition and SI/PI evaluation) are developed; thereby automation system for the SI/PI analysis is constructed with the algorithms. The automation of the circuit/EM simulation is accomplished in the environment of the C/S (Client/Server) architecture in order to reduce resources such as high cost computers demanded for the SI/PI analysis. The automation method for the SI/PI analyses proposed in this paper reduces effort, time, and cost spent on the environment setup for simulation and the SI/PI analysis process. In addition, the proposed method includes automation of the documenting process, which organizes, records and displays the SI/PI analysis results automatically for users.