• 한국정밀공학회지
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• 제21권6호
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• pp.43-51
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• 2004

A method for form error prediction in side wall machining with a flat end mill is suggested. Form error is predicted directly from the tool deflection without surface generation by cutting edge locus with time simulation. Developed model can predict the surface form error about three hundred times faster than the previous method. Cutting forces and tool deflection are calculated considering tool geometry, tool setting error and machine tool stiffness. The characteristics and the difference of generated surface shape in up milling and down milling are discussed. The usefulness of the presented method is verified from a set of experiments under various cutting conditions generally used in die and mold manufacturing. This study contributes to real time surface shape estimation and cutting process planning for the improvement of form accuracy.

• 한국건설관리학회논문집
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• 제3권4호
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• pp.114-122
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• 2002

EVMS(Earned Value Management System)는 최근 건설 프로젝트를 관리하는데 매우 유용한 도구로 인식되고 있으며, 정부차원에서 적극적으로 도입을 검토하고 있는 선진 관리기법이다. 이 EVMS는 미국방성에 의해 1960년대부터 프로젝트의 효율적인 관리를 위해 개발된 C/SCSC(Cost/schedule Control System Criteria)에 기반을 두고 있으며, 국내외에서 정부발주공사뿐만 아니라 민간발주의 건설프로젝트를 관리하는 도구로 활용하기 위해 연구가 활발하게 진행되고 있다. 본 연구에서는 공정관리 프로그램과 복합작업모델(Work Package Model)을 바탕으로 건설프로젝트의 EV계획단계의 관리계정계획(CAP)을 수립하는데 효과적으로 사용할 수 있는 방안을 제조업의 재고관리모형중의 한 형태로 조립제품의 자원운영계획을 수립하는데 우수한 기법으로 알려진 MRP(Material Requirement Planning)기법을 활용하여 제시하고자 한다.

• 한국게임학회 논문지
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• 제9권3호
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• pp.139-150
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• 2009

본 논문에서는 가상 에이전트의 행동 계획을 위한 인터렉티브 지식베이스 구축과 인터렉티브 지식베이스를 바탕으로 하는 계획시스템에 관한 방법을 제안한다. 고정적인 지식베이스는 고정적인 계획 수립만 가능하기 때문에 환경의 변화에 잘 대처하지 못한다. 그래서 이 논문에서는 다양한 환경에서 적용이 가능한 인터렉티브한 지식베이스의 구축과 인터렉티브 지식베이스를 활용할 수 있는 인공지능 계획시스템을 제안한다. 본 연구에서 제안한 인터렉티브 지식베이스는 동기, 행동, 사물, 실행의 4가지로 이루어지며 지식베이스의 입력과 지식베이스들 사이의 연관관계는 개발된 자동화 툴을 사용하여 설정한다. 이 툴을 사용하여 사용자는 쉽게 지식베이스에 구성요소들을 추가 또는 수정할 수 있다. 이 지식베이스를 바탕으로 캐릭터는 행동가능한 모든 항목들을 계획을 세우게 되며 이 중 한 가지를 선택하여 행동을 하게 된다. 후에 캐릭터의 환경이 변하게 되더라도 지식베이스의 업데이트를 통해 새로운 행동을 적용시킬 수가 있기 때문에 가상현실 콘텐츠제작자의 입장에서는 상당히 유용하다. 본 논문에서는 확장성이 있는 인터렉티브 지식베이스 구성요소와 구성요소들 사이의 관계설정 그리고 이를 쉽게 입력할 수 있는 툴과 인터렉티브 지식베이스에 적합한 계획시스템의 알고리즘을 제안하여 가상도서관이라는 가상환경에서 실험을 통해 결과를 검증하였다.

• Journal of Mechanical Science and Technology
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• 제20권1호
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• pp.19-28
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• 2006

This paper describes rapid prototyping (RP) and reverse engineering (RE) application for orthopedic surgery planning to improve the efficiency and accuracy of the orthopedic surgery. Using the symmetrical characteristics of the human body, CAD data of undamaged bone of the injured area are generated from a mirror transformation of undamaged bone data for the uninjured area. The physical model before the injury is manufactured from Poly jet RP process. The surgical plan, including the selection of the proper implant, pre-forming of the implant and decision of fixation positions, etc., is determined by a physical simulation using the physical model. In order to examine the applicability and efficiency of the surgical planning technology, two case studies, such as a distal tibia comminuted fracture and an iliac wing fracture of pelvis, are carried out. From the results of the examination, it has been shown that the RP and RE can be applied to orthopedic surgical planning and can be an efficient surgical tool.

• 산업공학
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• 제20권3호
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• pp.277-287
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• 2007

Semiconductor manufacturing is one of the most complex and capital-intensive processes composed of several hundreds of operations. In today’s competitive business environments, it is more important than ever before to manage manufacturing process effectively to achieve better performances in terms of customer satisfaction and productivity than those of competitors. So, many semiconductor manufacturing companies implement advanced planning and scheduling (APS) system as a management tool for the complex semiconductor manufacturing process. In this study, we explain roles of production planning and scheduling in semiconductor manufacturing and principal factors that make the production planning and scheduling more difficult. We describe the APS system implementation project at Korean semiconductor manufacturing company in terms of key issues with realistic samples.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2002년도 제21회 하계학술발표회 논문집
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• pp.125-139
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• 2002

This paper addresses the issue of increasing the effectiveness of national IT R&D planning through the adoption of the technology roadmapping process. As a needs-driven technology Planning tool, technology roadmapping can help identify and select technology alternatives to meet a set of market needs. Thus, it allows increasingly limited R&D investments to be used more efficiently. From this point of view, the Ministry of Information and Communication is considering introducing technology roadmapping to support its annual technology planning activity. In this contribution we explore how a technology roadmap could be integrated into IT technology planning and suggest some guidelines to successful technology roadmapping, on the basis of literature review, case survey and our experience, for organizations due to employ the roadmapping process in the future.

• KIEAE Journal
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• 제14권2호
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• pp.47-59
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• 2014

In the present circumstance of exploring measures for sustainable development, finding and using planning elements of historical city is getting important as a urban planning tool. Thus this study aims to examine the characters of Korean traditional urban form through three periods, Josun, modern and contemporary eras. Three urban centers representing different characteristics were selected; historical center based on 14th century's traditional planning, modern period urban center, which is related with development of railway, and contemporary urban center of late 20th century. Analyse of urban tissue, composed with form and scale of street network, blocks and plots, shows that each urban center of Seoul has certain common attributes in terms of morphology in spite of the difference of formation and development period. However this historical urban forms are rarely applicated in the current urban planning, such as new-town planning or district unit plan. This shows the necessity of modification of urban regulation for preserving the identity of our city and pursuing sustainable development.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.131-134
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• 2005

This paper presents a computer-aided simulation and robotic-assisted execution technology of external fixation method to achieve fracture reduction and deformity correction in long bones. Combining the kinematic analysis with a graphic model of the tibia and the fixator allowed 3D simulation and visualization of the adjustments required to reduce fracture or correct bone deformity as a pre-operative planning tool. The developed robot model provided accurate deformity correction with small residual deformity based on the results of the planning. By incorporating the robot model with image-guided system and computer-aided planning, the integrated system could be useful for computer-aided pre-operative planning and robotic-assisted execution in fracture treatment and bone deformity surgery.

• 한국정밀공학회지
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• 제7권3호
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• pp.56-65
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• 1990

This paper describes a computer aided tool design system of deep drawing of cylindrical cups with or without flange by press. An approach to system is based on knowledge based system. The computer program has written in basic language with personal computer Knowledges for tool design are formulated from the plasticity theory, handbooks, experimental results and empirical knowhow of the field experts. The capabilities of developed system include 1) the selection of tool structure (with or without blank holder, single or double action, lift up or draw off type), 2) the design of tool elements(punch/holder, die/holder etc.) for the previous selected tool structure by the process planning output and the production quantity. The final output is generated in graphics form for design sheet.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1998년도 추계학술대회 및 정기총회
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• pp.204-208
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• 1998

The fundamental issues to evaluate machine tool's performance through simulation pertain to the physical models of the machine tool itself and of process while the practical problems are related to the development of the modular software structure. It allows the composition of arbitrary machine/process models along with the development of programs to evaluate each state of machining process. Surface roughness is one of the fundamental factors to evaluate machining process and performance of machine tool, but it is not easy to evaluate surface roughness due to its tribological complexity. This paper presents an algorithm to calculate surface roughness considering cutting geometry, cutting parameters, and contact dynamics of cutting between tool and workpiece as well as tool wear in turning process. The designed virtual machining system can be used to evaluate the surface integrity of a turned surface during the design and process planning phase for the design for manufacturability analysis of the concurrent engineering.