• 산업공학
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• 제25권1호
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• pp.127-133
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• 2012

This paper considers the preventive maintenance scheduling problem of the cluster tool which is one of the most important manufacturing equipments in the next-generation semiconductor production environment. We define a random process that expresses the successive amount of chemicals accumulating inside the tool. Based on the renewal theory, we find the expected value and probability distribution of the time that the amount of accumulated chemicals exceeds a predetermined level. For a given probability that the accumulated chemicals exceeds the predetermined level we present a method to obtain the number of chamber operations to perform the preventive maintenance of that chamber. In addition, a method to get the preventive maintenance schedule for the whole cluster tool is presented. A numerical example is provided to illustrate our method.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.475-478
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• 2004

Tool costs can comprise a significant part of the total operating costs of Flexible Manufacturing Systems. We address the problem of determining the optimal processing times of individual operations and routing mix in FMSs with multiple routes for each part type in order to minimize tool cost, subject to meeting a throughput constraint for each part type. The problem is formulated as a nonlinear program superimposed on a closed queueing network of the FMSs under consideration. Numerical examples reveal the potential of our approach for significant saving in tool costs.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 춘계학술대회
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• pp.195-198
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• 2001

This paper addresses the problem of placing tools in a tool magazine with random-select capability on a flexible machine. The tool placement problem could be a significant portion of the total processing time. It is assumed that the total number of tools required to process a set of parts exceeds the available magazine capacity, and so tool switches may occur between two adjacent parts in a given part sequence. Two heuristics are presented so as to minimize the total travel distance of the tool magazine before the completion of all parts.

• Asia pacific journal of information systems
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• 제6권1호
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• pp.241-267
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• 1996

The problems like exceeding estimated cost, late due-date, expensive maintenance, insuffiency of experts and low productivity are becoming emphasized related with the software development. In order to overcome these problems and to develop the highly qualified software within the limited resources, a project management tool is used. The purpose of this study is to develop a conceptual model of the project management system which can plan, analyze and control the software development projects effectively. The model is constructed with plan and track management system, cost management system and operation management system for the efficient project management. It is named by LSD-PMS : Large-scale Software Development Project Management System. We reviewed 5 cases of project management. LSD-PMS is evaluated and reviewed by the project managers in the field. It is proved that LSD-PMS is a tool which can help project managers develop software successfully given budget and time schedule. In the future, this system should be further developed as an integrated model with system implementation tools such as CASE products.

• 한국게임학회 논문지
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• 제8권4호
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• pp.65-73
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• 2008

본 논문에서는 발달장애 아동의 교육 및 치료에 있어서 감각, 인지훈련을 효과적으로 할 수 있는 에듀테인먼트 플랫폼을 제시한다. 이를 위해 임베디드 하드웨어를 개발하고 여기서 재생할 콘텐츠를 제작하기 위한 저작도구, 학습 결과를 확인할 수 있는 관리도구, 학습 상황을 실시간으로 모니터링하는 도구를 개발하였다. 발달장애 아동의 특성을 관찰 분석하여 개발한 하드웨어는 주의집중을 위한 감각훈련을 집중적으로 할 수 있도록 시각, 청각, 촉각 등의 자극을 제공한다. 이와 함께 개발한 소프트웨어는 특수교사 이외의 비전문가도 쉽게 교육용 콘텐츠를 만들고 학습 현장이외에서도 학습상황을 볼 수 있도록 하는 기능을 제공한다. 또한, 학습한 결과를 다음 학습단계로 적용할 수 있도록 이를 보관하고 살펴 볼 수 있는 기능도 제공한다. 이를 통해 시간, 장소의 제한 없이 효과적으로 반복 학습을 수행이 가능하다. 개발한 플랫폼을 직접 교육현장에 적용해봄으로써 주의집중과 학습 능력을 높이는데 효과가 있음을 알 수 있었다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.105-110
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• 2006

건설공사에서 발생하는 리스크는 시공단계에 많이 발생하므로 공정관리와 통합하여 관리할 수 있다면 효율적일 것이다. 본 연구에서는 공정관리 프로그램을 이용하여 공정리스크를 통합관리하는 방법을 제안하고 있다. 제안된 방법은 사용자 프로그래밍(Visual Basic Application)이 가능한 Microsoft Project에서 구현되었으며, 공사관리자가 공정표를 작성하고 일정관리를 수행하는 과정에서 리스크를 예측하는데 도움을 줄 수 있을 것이다.

• 품질경영학회지
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• 제26권4호
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• pp.51-64
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• 1998

Mean shifts may be found in tool wear in machining, drawing, stamping and moulding operations, which make the process quality level deteriorate over time. In such situations, it is necessary to reset or readjust the manufacturing process at regular time basis or by inspection to prevent defective items produced. Although the deterioration rate may be assumed to be linear in a production cycle, there are many cases where the rate varies after resetting due to the variation of tool characteristics or by using the resharpened tools. In such cases, the deterioration rate should not be assumed to be a deterministic constant but a random variable. This paper is to find an optimal resetting period and quality level for such production processes.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.610-614
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• 1996

In machining muliple components fixed on the same pallet of a NC machine, it is very important to minimize the total time required to finish the machining by carefully determining the component layout on the pallet, and the tool path of NC machine, and the sequence of tools to be used. In this paper, a linear integer programming model is presented to obtain an efficient layout; and a two-phased heuristic algorithm is proposed to minimize the total time for machining multiple components. Numerical examples are given for the case of identical components and nonidentical components, respectively. The result of either case shows significant reduction of 7.2~15.0% in the total time required to finish the machining.

• Journal of Construction Engineering and Project Management
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• 제7권2호
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• pp.19-33
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• 2017

Various forms of procurement are open to companies when constructing new owner-occupied properties. The selection of a form of procurement is an important decision-making problem for companies and their Corporate Real Estate Management (CREM) departments. With this in mind, a decision support tool has been developed to optimise the outcome and success of company's proposed real estate development projects and is presented in this paper. This model can also be used for current real estate portfolios to optimise returns in the long term. In pursuit of this objective and in order to provide an academic basis for this study, decision-relevant goals and parameters were initially identified from the referenced literature used in our research. These were subsequently evaluated in a case study of a corporate development project and identified as specific decision criteria from the perspective of the CREM. The investigation identified 15 criteria that are relevant to the corporate decision-making process in procuring and/or developing property. A model for supporting and resolving decision-making problems of this type was derived from decision theory. In this paper, a decision-making tool is presented that takes into account all the decision criteria from the CREM point of view for the first time. This model should therefore serve as an aid in implementing the decision-making process for the development of real estate projects in a more structured and transparent manner.

• 한국컴퓨터정보학회논문지
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• 제13권6호
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• pp.41-49
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• 2008

최근 생물정보학에서의 워크플로우 관리 도구를 이용한 생명 현상에 대한 연구가 활발하게 진행되고 있다. 워크플로우 관리 도구는 서비스의 재사용과 공유를 통해 연구자들이 서로 협업할 수 있는 기반으로 MyGrid 프로젝트의 Taverna를 비롯하여 Kepler, BioWMS 등의 다양한 워크플로우 관리 도구들이 오픈소스로 개발되어 사용 되고 있다. 이러한 워크플로우 관리 도구는 공간적으로 떨어진 서로 다른 서비스들을 웹 서비스 기술을 기반으로 하나의 작업공간에서 연구 과정을 모델링하고 자동화 할 수 있도록 해준다. 생물정보학에서 사용되는 많은 도구와 데이터베이스들이 웹 서비스 형태로 제공되어 워크플로우 관리 도구에서 사용되고 있다. 이러한 상황에서 생물정보학에서 기본으로 사용되는 서열 유사성 검색에 대한 웹 서비스의 개발과 안정적인 서비스 제공은 생물정보학 분야에서 필수적이라 할 수 있다. 본 논문에서는 리눅스 클러스터를 기반으로 생물학 서열 데이터의 유사성 검색 속도를 향상시키는 한편, 이를 웹 서비스 형태로 개발하여 워크플로우 관리 도구와의 연동하여 단시간에 서열 유사성 검색을 가능하게 하였다.