• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.312-315
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• 1998

There have been great advances in communication and networking in recent times. It is necessary to take advantage of this information infrastructure for the purpose of developing an engineering education system. But the networking system was expensive or hard to develop. The current international networking is converging to the use of the World Wide Web system. It has become a new standard for global network communication. But there are not a great number of applications which take full advantage of this environment. In this paper an interactive education system for engineering education using the World Wide Web will be presented. This can be used as a supplementary kit for engineering education of transformer induction motor design. The system is developed using JAVA and can be accessed using Web browsers.

• 대한전기학회논문지:전력기술부문A
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• 제54권4호
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• pp.165-171
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• 2005

Electromagnetic transient simulation can be used to model complex non-linearities that very difficult to represent adequately in the frequency domain. This problem is greatly reduced with the use of frequency dependent network equivalents for the linear part of the system. S-domain rational function fitting techniques for representing frequency dependent equivalents have been developed using Least Squares Fitting(LSF). However it does not suffer the implementation error that exited in this work as it ignored the instantaneous term. This paper presents the formulation for developing 2 port Frequency Dependent AC System Equivalent(FDACSE) with the instantaneous term in S-domain and illustrates its use. This 2 port FDNE have been applied to the New Zealand AC system. The electromagnetic transient package PSCAD/EMTDC is used to assess the transient response of the 2 port (FDACSE) developed with Norton Equivalent network. The study results have indicated the robustness and accuracy of 2 port FDACSE for electromagnetic transient studies.

• 한국정밀공학회지
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• 제15권11호
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• pp.21-31
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• 1998

This study described computer aided die design system for cold forging of non-axisymmetric parts. To design the die of cold forging. an integrated approach based on a rule-base system and commercial F. E. code were adopted. This system is implemented on the personal computer and its environment is a commercial CAD package named as AutoCAD. The system includes four modules. In the initial data input module, the variables which are necessary to design of die are inputted by user and die material are selected from the database. In the analysis and redesign module, stress distrubution action on the designed die is analyzed by commercial FEM code NISA II. The designed die is modified to prevent failure in both states of stress free and pressurizing. The developed system provides powerful capabilities for die design of non-axisymmetric parts.

• 한국기계가공학회지
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• 제18권6호
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• pp.19-25
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• 2019

We have developed a tool that uses finite element analysis (FEA) to rapidly evaluate a shaft-bearing system of machine tools. We extracted commercial data on suitable clamping units and defined the inner profile of the shaft to avoid needing direct user input to define the profile. We use a splitting algorithm to convert the shaft into beam elements with two diameters and length. To validate the tool, we used it to design and evaluate a shaft-bearing system and found that our tool automated the construction of an FE system model in a commercial FEA package as well as the static stiffness evaluation; both tasks were completed in seconds, demonstrating a significant reduction from the minutes normally required to complete these tasks manually.

• 한국건설관리학회논문집
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• 제10권1호
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• pp.45-57
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• 2009

교육시설물 BTL 사업은 여러 개의 시설물을 1개의 번들로 계약하며, 계약기간을 20년으로 산정하여 그 비용을 지급한다. 따라서 BTL 프로젝트 초기단계에 운영관리비를 예측하는 정확도와 발주번들에 포함되는 시설물을 어떻게 편성하느냐에 따라 비용편차가 크게 발생하게 된다. 본 연구에서는 교육시설물 BTL 사업 발주 시 운영관리 최적 번들을 구성하기 위한 방법으로 컴플리트 링키지 알고리즘을 이용하는 비용 예측 시스템을 개발하고, 이를 통해 발주번들에 포함되는 시설물 변화에 따라 제한조건들이 변화하는 경우에 대해 사용자의 의사결정 시 판단근거자료로 활용 가능하게 하고자 한다. 본 연구에서 제안하는 시스템을 활용하면 보다 효율적이고 신속한 BTL 프로젝트의 운영비 예측이 가능할 것으로 사료된다.

• 한국컴퓨터정보학회논문지
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• 제12권1호
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• pp.243-252
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• 2007

최근 들어, 중소기업에서의 기업자원관리시스템 구현에 관한 관심과 연구가 꾸준히 증가하고 있다. 본 연구에서는 중소기업에서의 기업자원관리(ERP) 소프트웨어 품질, 벤더의 지원, 사용자 정보 만족도 및 ERP 구현 성과와의 관련성을 규명하였다. 이와 같은 실증연구를 통하여 ERP 소프트웨어 품질과 벤더의 지원이 중소기업에서의 성공적인 ERP 구현과 밀접한 관련이 있음을 제시하였다. 본 연구는 내부자원이 상대적으로 부족한 중소기업의 ERP 시스템 구현에 있어서 패키지 소프트웨어 품질과 벤더의 지원에 대한 의존성과 중요성에 관한 시사점을 제공하였다.

• 반도체디스플레이기술학회지
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• 제18권4호
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• pp.149-153
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• 2019

The technology of electronic packaging among semiconductor technologies is evolving as an axis of the market in its own field beyond the simple assembly process of the past. In the field of electronic packaging technology, the packaging of power modules plays an important role for green electric vehicles. In this power module packaging, the thermal reliability is an important factor, and silicon nitride plays an important part of package substrates, Silicon nitride is a compound that is not found in nature and is made by chemical reaction between silicon and nitrogen. In this study, this core material, silicon nitride, was fabricated by reaction bonded silicon nitride. The fabricated silicon nitride was studied for thermo-mechanical properties, and through this, the structure of power module packaging was made using reaction bonded silicon nitride. And the characteristics of stress were evaluated using finite element analysis conditions. Through this, it was confirmed that reaction bonded silicon nitride could replace the silicon nitride as a package substrate.

• 산업경영시스템학회지
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• 제39권2호
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• pp.88-102
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• 2016

This paper considers the allocation and engagement scheduling problem of interceptor missiles, and the problem was formulated by using MIP (mixed integer programming) in the previous research. The objective of the model is the maximization of total intercept altitude instead of the more conventional objective such as the minimization of surviving target value. The concept of the time window was used to model the engagement situation and a continuous time is assumed for flying times of the both missiles. The MIP formulation of the problem is very complex due to the complexity of the real problem itself. Hence, the finding of an efficient optimal solution procedure seems to be difficult. In this paper, an efficient genetic algorithm is developed by improving a general genetic algorithm. The improvement is achieved by carefully analyzing the structure of the formulation. Specifically, the new algorithm includes an enhanced repair process and a crossover operation which utilizes the idea of the PSO (particle swarm optimization). Then, the algorithm is throughly tested on 50 randomly generated engagement scenarios, and its performance is compared with that of a commercial package and a more general genetic algorithm, respectively. The results indicate that the new algorithm consistently performs better than a general genetic algorithm. Also, the new algorithm generates much better results than those by the commercial package on several test cases when the execution time of the commercial package is limited to 8,000 seconds, which is about two hours and 13 minutes. Moreover, it obtains a solution within 0.13~33.34 seconds depending on the size of scenarios.

• Journal of the Korean Data and Information Science Society
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• 제15권2호
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• pp.317-329
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• 2004

The Web log has caught much attraction for tracing of customer activity. So many researches have been carried on it. As a result, Web log analysis solutions has been developed and launched lately. It has been in the spotlight to the website administrators and people in practical marketing business. In this paper, we made an analysis on the various behavior patterns of customers in cooperation with SAS/AF and SCL modules, based on development of GUI from SAS package for disposal of statistical data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.252-255
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• 1990

Analyzing and simulating of today's complex electrical networks require the use of computer-aided engineering tools. In recent years, the rapid advances in micro-computer hardware technology have increased the availability of power application software on the personal computer, once the domain of mainframes and minicomputers, enabling efficient and cost-effective power system analysis. An interactive simulation and analysis software for a power system is developed and presented in this paper. The software is written in PASCAL and is designed for PC use. This paper presents an integrated software package to run PC-DOS for the analysis of electric power networks. The software is menu driven and controlled by prompts. These programs are intended to help users understand the process of power system analysis and design.