• 대한산업공학회지
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• 제22권4호
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• pp.719-739
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• 1996

A common control model used to implement computer integrated manufacturing(CIM) is based on the hierarchical decomposition of the shop floor activities, in which supervisory controllers are responsible for all the interactions among subordinates. Although the hierarchical control philosophy provides for easy understanding of complex systems, an emerging manufacturing paradigm, agile manufacturing, requires a new control structure necessary to accommodate the rapid development of a shop floor controller. This is what is called autonomous agent-based heterarchical control. As computing resources and communication network on the shop floor become increasingly intelligent and powerful, the new control architecture is about to come true in a modern CIM system. In this paper, heterarchical control is adopted and investigated, in which a controller for a unit of device performs three main functions - planning, scheduling and execution. Attention is paid to the planning function and all the detailed planning activities for heterarchical shop floor control are identified. Interactions with other functions are also addressed. In general, planning determines tasks to be scheduled in the future. In other words, planning analyzes process plans and transforms process plans into detailed plans adequate for shop floor control. Planning is also responsible for updating a process plan and identifying/resolving replanning activities whether they come from scheduling or execution.

• 한국해양공학회지
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• 제18권3호
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• pp.26-31
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• 2004

This paper presents a process planning system that will generate and verify assembly sequences of block assemblies. It consists of a CAD interface system and an assembly sequence planning system. In developing this system, we used an open architecture CAD kernel for the CAD interface system, for visualizing the CAD model and the assembly sequences, and an expert system shell for the assembly sequence planning system. This paper also proposes a framework for the integration of all the steps required to automate the procedures, from design to production. The process planning system is demonstrated by a simple example.

• 산업경영시스템학회지
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• 제21권46호
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• pp.181-196
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• 1998

The aim of this research is the development of a CAPP system which can use the old experience of process planning to generate a process plan for a new part and learn from its own experience using the concept of stratified case-based reasoning(CBR). A process plan is determined through the hierarchical process planning procedure that is based on the hierarchical feature structure of a part. Each part and case have their own multiple abstractions that are determined by the feature structure of the part. Retrieving the case in stratified case-based process planning is accomplished by retrieving the abstraction that is most similar to the input part abstraction in each abstraction level of the case-base. A new process plan is made by the adaptation that translates the old case's process plan into the process plan of a new part. Operations, machines and tools, setups and operation sequence in each setup are determined in the adaptation of abstraction using some algorithms and the reasoning based on knowledge-base. By saving a new part and its process plan as a case, the system can use this new case in the future to generate a process plan of a similar part. That is, the system can learn its own experience of process planning. A new case is stored by adding the new abstractions that are required to save as the new abstraction to the existing abstractions in the case-base.

• 한국IT서비스학회지
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• 제8권3호
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• pp.159-169
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• 2009

The issue of method of software testing process implementation has recently been in the spotlight in korea and some vendor make every effort to improve the software testing process through the evaluation of TMMi. The level of software process is at initial level, nevertheless, so the high quality of software is not guaranteed. This paper apply to the TMMi Level2 Assessment criteria of Automobile control software testing process. The test policy and strategy, test planning, test monitoring and control, test design and execution, test environment goal. The result need to emerge development process connection on the test policy and strategy process, test planning process etc. Also, the study analyzed the infra structure to reach the repeated level via key process area. As the result the process implementation in organization suggests the policy development and the implementation activity. Finally, the practical can refer to this paper in order to implementation the software testing process.

• 과학교육연구지
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• 제33권2호
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• pp.271-289
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• 2009

이 연구는 생물학자와 과학영재의 실험설계활동에서 나타나는 과정요소와 특성을 분석한 것이다. 연구대상으로 동물행동생태를 전공한 생물학자 4명과 과학영재 생물반 학생 32명을 선정하였고, 연구를 위해 주어진 과제는 Fowler(1990)의 DCT이다. 그들의 실험설계활동과 관련된 모든 자료를 수집하였고, 이 자료를 분석하기 위한 분석틀을 개발하였다. 분석 결과, 첫째, 생물학자와 과학영재의 실험설계활동에서 나타난 과정요소는 문제 확인, 준비물 열거, 실험대상에 대한 고려, 변인 탐색, 변인 소거, 변인 선택, 변인 조작 방법 계획, 환경적 변인 통제 계획, 생물적 변인 통제 계획, 관찰 측정 방법 계획, 자료 수집 계획, 자료 해석 계획, 실험의 반복 계획, 측정의 반복 계획, 안전 수칙으로 총 15가지가 있다. 생물학자는 특정한 과정요소에 집중하는 반면, 과학영재는 정형화된 과정요소를 나타냈다. 둘째, 생물학자와 과학영재의 실험설계활동에서 나타난 특성을 종합하면 다음과 같다: 1) 생물학자와 과학영재 모두 영역특수적인 과정기술이 포함된 과정요소를 나타냈다. 2) 생물학자는 특정한 과정을 반복적으로 점검하면서 정교하게 실험을 설계하는 반면, 과학영재는 피상적으로 실험을 설계한다. 3) 생물학자는 영역특수적인 기술과 노하우를 가지고 있으나, 과학영재는 그렇지 않다. 이러한 결과는 과학영재의 실험설계활동 교육 프로그램은 생물학자들이 집중하는 과정요소를 중심으로 구성하고, 정교한 실험 설계를 할 수 있도록 피드백을 제공하고, 생물학자의 과정기술이나 노하우를 학습할 수 있는 형태로 개발되어야 함을 시사한다.

• 한국정밀공학회지
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• 제19권1호
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• pp.107-118
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• 2002

This paper deals with an automated computer-aided process planning and die design system by which designer can determine operation sequences even if they have a little experience in process planning and die design of quasi-axisymmetric cold forging product by cold former working. The approach to the system is based on knowledge-based rules and a process knowledge base consisting of design rules is built. Knowledge for the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for the AutoCAD using a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM softwares, DEFORM and ANSYS, to form a useful package. The system is composed of three main modules and five sub-modules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available cold farmer, and the availability of standard parts. As the system using 2D geometry recognition is integrated with the technology of process planning, die design, and CAE analysis, the standardization of die parts for wheel bolt requiring cold forging process is possible. The developed system makes it possible to design and manufacture quasi-axisymmetric cold forging product more efficiently.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.214-218
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• 1995

Much labor, an exceedingly long lead time, and the skills of experienced engineers are required for press tool design. To reduce such problems, several CAD systems for blanking or piercing have been developed. This paper describes a computer-aided design for blanking or piercing of irregularly shaped sheet metal products. An approach to the system is based on knowledge base rules. The process planning & die design system is designed by considering several factors, such as complexity of blank geometry, punch profile, and availability of press equipment and standard parts. Therefore, after checking a production feasibility for irregular shaped sheet metal products, this system which is implemented strip layout module can carry out a process planning and generate the strip layout in graphic forms. Also this system implemented die layout module can carry out a die design for each process which is obtained form the result of an automated process planning and generate parts and assembly drawing of a die set.

• 한국CDE학회논문집
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• 제11권3호
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• pp.223-233
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• 2006

Layered manufacturing(LM) is emerging as a new technology that enables the fabrication of three dimensional heterogeneous objects such as Multi-materials and Functionally Gradient Materials (FGMs). Among various types of heterogeneous objects, more attention has recently paid on the fabrication of FGMs because of their potentials in engineering applications. The necessary steps for LM fabrication of FGMs include representation and process planning of material information inside an FGM. This paper introduces a new process planning algorithm that takes into account the processing of material information. The detailed tasks are discretization (i.e., decomposition-based approximation of volume fraction), orientation (build direction selection), and adaptive slicing of heterogeneous objects. In particular, this paper focuses on the discretization process that converts all of the material information inside an FGM into material features like geometric features. It is thus possible to choose an optimal build direction among various pre-selected ones by approximately estimating build time. This is because total build time depends on the complexity of features. This discretization process also allows adaptive slicing of heterogeneous objects to minimize surface finish and material composition error. In addition, tool path planning can be simplified into fill pattern generation. Specific examples are shown to illustrate the overall procedure.

• 한국경영과학회지
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• 제29권2호
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• pp.77-95
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• 2004

This paper deals with the process planning of flexible manufacturing systems (FMS) with various flexibilities and multiple objectives. The consideration of the manufacturing flexibility is crucial for the efficient utilization of FMS. The machine, tool, sequence, and process flexibilities are considered In this research. The flexibilities cause to increase the Problem complexity. To solve the process planning problem, an this paper an evolutionary algorithm is used as a methodology. The algorithm is named multiobjective competitive evolutionary algorithm (MOCEA), which is developed in this research. The feature of MOCEA is the incorporation of competitive coevolution in the existing multiobjective evolutionary algorithm. In MOCEA competitive coevolution plays a role to encourage population diversity. This results in the improvement of solution quality and, that is, leads to find diverse and good solutions. Good solutions means near or true Pareto optimal solutions. To verify the Performance of MOCEA, the extensive experiments are performed with various test-bed problems that have distinct levels of variations in the four kinds of flexibilities. The experiments reveal that MOCEA is a promising approach to the multiobjective process planning of FMS.

• 과학기술학연구
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• 제4권2호
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• pp.103-127
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• 2004

본 연구에서는 미 항공우주국 (NASA)의 전략기획을 공공 연구개발 조직의 전략기획이란 관점에 의하여 분석하였다. 이를 위하여 전략경영과 전략기획에 대한 일반적인 논의, 공공부문에서의 적용, 연구개발조직의 특성 등을 고려하여 공공 연구개발 조직의 전략경영 및 전략기획의 분석틀을 제시해 보았다. 그리고 구성된 틀에 의하여 미항공우주국과 산하 연구소인 고다드 우주비행 센터의 전략기획 과정과 특징을 분석하였다. 이에 의하면 공공연구개발 조직에서 전략기획을 수행함에 있어 다음과 같은 시사점을 생각해 볼 수 있다. 첫째, 민간부문의 전략기획 과정과 공공부문의 전략기획 과정의 차이점을 고려해야 할 것이다. 둘째, 전략의 수립과정에 있어 기관과 외부의 이해관계자와의 관계에 대한 논의가 있어야 한다. 셋째, 연구개발의 사회경제적 효과의 확인과 측정, 그것의 기관 목표설정으로의 환류방안에 대한 논의가 필요하다. 넷째, 전략기획이 조직 내에서 실질적인 효과를 가지려면 경영목표, 예산, 기관평가 등 기존의 기관 운영시스템과 긴밀하게 연결되어야 한다는 점이다. 이러한 점들이 잘 고려되어 도입에 성공한다면, 연구개발기관의 고유 임무 특성에 맞는 운영과 평가가 가능해 질 것이다. 향후 보다 적실성 있는 연구결과를 위해서는 실제 공공연구개발기관의 전략경영 과정에 대한 심도 있는 연구와 성과지표 등에 대한 유형별 분석이 필요하다. 이러한 과정에서 실제 관련 실행 사례의 현황과 문제점에 대한 분석을 축적함으로써 다양한 시사점들이 종합되어야 할 것이다.