• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.375-379
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• 1993

공정계획(process planning)이란 제품에 대한 설계정보 및 제한된 가용자원에 대한 정보를 바탕으로 비용, 생산량을 고려하여 원자재를 원하는 형태로 변형시키기 위한 방법의 체계적인 결정과정이라 할 수 있으며, 생산계획(production planning: scheduling)이나 작업계획(operation planning)과 연계하여 설계와 생산을 연결하는 교량 역할을 수행한다. 이러한 공정계획 작업을 컴퓨터에 의해 자동화하기 위한 컴퓨터 원용 공정계획(computer aided process planning : CAPP)은 변환적 방식(variant approach)에서 시작되어 창생적 방식(generative approach)으로 발전되어 왔으며 인공지능 기법을 응용 한 지식기반 CAPP(knowledge based CAPP) 방식에 이르기 까지 CAM-1's CAPP, APPAS, GARE, SIPS, XCUT등 수많은 연구가 행해 졌다. 본 연구에서는 자동차 부품 업체인 K사의 공정계획 사례를 바탕으로 범용성이 있는 개방형 공정계획 시스템의 개발을 목표로 한다. 본 시스템에서 i) 설계정보는 객체지향에 의해 표현된 형상특징을 사용하고 ii) 공정계획은 국부적 공정계 획과 전체적 공정계획 과정(golbal planning)으로 구별하였고 iii) 공정계획을 위한 정보는 지식 베이스(knowledge base : KB) 와 데이타 베이스(data base : DB)로 구분하였다. 또한 iv) 정보의 모듈화를 통하여 임의의 제조라인에 적합하도록 개방형을 추구하였다.

• 대한산업공학회지
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• 제20권3호
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• pp.125-137
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• 1994

Manufacturing environs constantly change, and any efficient software system to be used in manufacturing must be able to adapt to the varying situations. In a CAPP (Computer-Aided Process Planning) system, a learning capability is necessary for the CAPP system to do change along with the manufacturing system. Unfortunately only a few CAPP systems currently possess learning capabilities. This research aims at the development of a learning system which can increase the knowledge in a CAPP system. A part in the system is represented by frames and described interactively. The process information and process planning logic is represented using a decision tree. The knowledge expansion is carried out through an interactive expansion of the decision tree according to human advice. Algorithms for decision tree modification are developed. A path can be recommended for an unknown part of limited scope. The processes are selected according to the criterion such as minimum time or minimum cost. The decision tree, and the process planning and learning procedures are formally defined.

• 한국정밀공학회지
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• 제13권9호
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• pp.46-53
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• 1996

This paper describes some research works of computer-aided design of blanking and piercing for stator and rotor parts and irregularly shaped sheet metal by press. An approach to the system is based on knowledge based rules. The process planning system by considering a blank layout for nesting of irregularly shaped sheet metal and an improved strip layout for stator and rotor parts and irregularly shaped sheet metal is implemented. Using this system, design parameters(utilization ratio, slitting width, pitch, working order, die blank shapes) are determined and output is generated in graphic forms. Knowledges for blank layout and strip layout are extracted from the plasticity theories, handbooks, relevant references and empirical know-hows of experts in blanking companies. The implemented system provides powerful capabilities for process planning of stator and rotor parts and irregularly shaped sheet metal.

• 한국정밀공학회지
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• 제17권3호
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• pp.102-107
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• 2000

This study describes computer-aided design system for stepped asymmetric forgings. To establish the appropriate process sequence, an integrated approach based on a rule-base system was accomplished. This system has four modules, which are undercut prevention module, shape cognition module, 3D modelling module and corner/fillet correction module. These modules can be used independently or at all. The proposed shape cognition method could be widely used in forging design of asymmetric parts.

• 한국CDE학회논문집
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• 제5권3호
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• pp.255-262
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• 2000

A computer-aided process planning (CAPP) system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. Therefore, this study investigates process sequence design in deep drawing process and constructs an expert system of process planning for non-axisymmetric motor frame products with elliptical shape. The system developed consists of four modules. The first one is recognition of shape module to recognize the products. The second one is a 3-D modeling module to calculate surface area for non-axisymmetric products. The third one is a blank design module that creates an oval-shaped blank with the identical surface area. The forth one is a process planning module based on production rules that play the best important role in an expert system for manufacturing. The production rules are generated and upgraded by interviewing with field engineers. The constructed system using AutoLISP language under the AutoCAD environment is baled on the knowledge base system which is involved a lot of expert's technology. Results of this system will be provide effective aids to the designer and engineer in this field.

• 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.

• 한국군사과학기술학회지
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• 제2권2호
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• pp.83-91
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• 1999

Dynamic characteristic of manufacturing stage is understood and the utilization of each machine is maximized by developing on-line dynamic CAPP system to consider the overloads in the aircraft part manufacturing line. In this paper, a scheme of production planning and scheduling system was proposed through inspection about some predeveloped CAPP system. Developed production planning and scheduling system included process planning module. After precise inspection of some FMS line schema at domestic heavy industry, optimized FMS line was applied to aircraft part manufacturing and repairing factory. By virtue of considering overloads of factory and machine through on-line dynamic CAPP system, the utilization of resources is maximized and manufacturing lead time is minimized.

• 한국정밀공학회지
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• 제13권8호
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• pp.40-51
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• 1996

This paper describes some research works of computer-aided design of blanking and piercing progressive die for stator and rotor parts. An approach to the system is based on knowledge based rules. The deveolped system is composed of six modules such as main program, input and shape treatment, production feasibility check, strip layout, die layout and drawing edit module. Using this system, design parameters ( geometric shapes, die and punch dimensions and dimensions of tool elements) are determined and output is gen- erated in graphic from. Knowledges for tool design are extracted from the plasticity theories, handbooks, relevant references and empirical know-hows of experts in blkanking companies. The developed system provides powerful capabilities for process planning and die design of stator and rotor parts.

• 한국정밀공학회지
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• 제20권4호
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• pp.29-38
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• 2003

This paper deals with an automated computer-aided process planning and die design system with which designer can determine operation sequences even after only a little experience in process planning and die design of multi former-bolt products by multi-stage former working. The approach is based on knowledge-based rules, and a process knowledge base consisting of design rules is built. Knowledge fur 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 AutoCAD with 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 four main 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 multi former, and the availability of standard parts. It can provide a flexible process based on either the reduction in the number of forming sequences by combining the possible two processes in sequence, or the reduction of deviation of the distribution and the level of the required forming loads by controlling the forming ratios. The system uses 2D geometry recognition and is integrated with the technology of process planning, die design, and CAE analysis. The standardization of die parts for multi former-bolt products requiring a cold forging process is described. The system developed makes it possible to design and manufacture multi former-bolt products more efficiently.

• 지능정보연구
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• 제4권1호
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• pp.1-10
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• 1998

Process planning is a very complex task and requires the dynamic informatioon of shop foor and market situations. Process plan selection is one of the main problems in the process planning. In this paper, we propose a new process plan selection model considering operation flexibility for the computer aided process planing. The model is formulated as a 0-1 integer programming considering realistic shop factors such as production volume, machining time, machine capacity, transportation time and capacity of tractors such as production volume, machining time, machine capacity, transportation time capacity of transfer device. The objective of the model is to minimize the sum of the processing and transportation time for all parts. A genetic algorithm a, pp.oach is developed to solve the model. The efficiency of the proposed a, pp.oach is verified with numerical examples.