• Journal of the Korean Society for Precision Engineering
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• v.19 no.1
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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.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.55-63
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• 1991

This paper deals with development of a Computer Aided Process Planning System based on knowledge base in addition to database for injection mold as a part of Computer Integrated Manufacturing System for injection mold manufacture. The prposed system consists of four modules such as manufacturing feature code generation module machine tool selection and sequencing module, operation and cutting tool selection mudule and standard time estimation module. The system is programmed by using Turbo Pascal on the IBM-PC/AT. The performance of the system is evaluated by using real problems and the test results indicate that the proposed system is a practical and efficient system.

• Management Science and Financial Engineering
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• v.11 no.2
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• pp.45-60
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• 2005

This paper investigates the application of the computer method COMSOAL (Computer Method of Sequencing Operations for Assembly Lines) to the process routing (PR) problem with multiple objectives. In any computer aided process planning (CAPP) system, one of the most critical activities for manufacturing a part could be to generate the sequence that optimizes production time, production cost, machine utilization or with multiple these criteria. The COMSOAL has been adopted to find the optimum sequence of operations that optimizes two major conflicting criteria : production cost and production quality. The COMSOAL is here slightly modified to simultaneously generate and evaluate a set of possible solutions (called as population) instead of processing a solution stepwise in each iteration. The significant features of the COMSOAL include : no parameters settings needed, and a guarantee of feasible solutions. Experimental results show that COMSOAL is a simple but powerful method to quickly generate multiple feasible solutions which are as good as the ones obtained from several other well-known process routing algorithms.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.32-40
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• 2004

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 for axisymmetric products. 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 the die design modules consider several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available multi former, and the availability of standard parts. They 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 on the level of the required forming loads by controlling the forming ratios. Especially in die design module an optimal design technique and horizontal split die were investigated for determining appropriate dimensions of components of multi-former die set. It is constructed that the proposed method can be beneficial for improving the tool life of die set at practice.

• Korean Journal of Computational Design and Engineering
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• v.18 no.1
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• pp.1-9
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• 2013

Nowadays in order to perform assembly process planning by using CAPP (Computer Aided Process Planning), researches to generate the assembly sequence automatically have come under constant interest by many researchers and they are devoted to optimize the assembly sequence. In this paper, the product on analyzing the relationship between assembled parts via contacting information such as common area, automatically based on the liaison graph of the product. To verify the validness and efficiency of the approach, the simple product is tested in the experimental way.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.774-777
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• 2001

This paper describes a research work of developing a computer-aided design system of cold forging products. An approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plastic theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoCAD with a personal computer and is composed of six modules, which are selection of billet material, input of final product, process planning design, preform modification, insert design, shrink rings design module. Based on knowledge-based rules, the system is designed by considering several factors such as volume constancy, limite of formability by material, preform shape and so on.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.74-80
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• 2007

In manufacturing industry, machining technology for metal cutting processes has been considered traditional and economic dimensions such as production cost, production time and quality of a final product. However, owing to governmental regulations and the change of owner's cognizance, the safety of the workers becomes important in those fields. In this paper, the operation planning system developed as a key component of CAPP(Computer Aided Process Planning) system is introduced for milling operations. The main issue in the system is to determine the cutting conditions in achieving a balanced consideration of productivity and worker's safety. For this reason, the system performs the modification process of standard cutting conditions to satisfy those requirements. Related to machining safety in metal cutting, representative and habitual mistakes that operators perform without considering carefully the characteristic of machine or work piece are described and then the detailed algorithm and functions of the developed system is introduced and discussed.

• Asia pacific journal of information systems
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• v.9 no.2
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• pp.19-37
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• 1999

Computer aided process planning(CAPP) is a key for implementing CIM. It is bridge between CAD and CAM and translates the design information into manufacturing instructions. Generally, manufacturing is an area where intelligent systems will not be able to rely on methods requiring formalized knowledge. Manufacturing lacks a body of knowledge that is specific, formalized, and rigorous, and which can be coded as rules or procedures. Thus expertise in manufacturing is developed over a period of many years. Case-based reasoning(CBR) offers a new approach for developing intelligent system. In the case-based approach the problem solving experience of the experts is encoded in the form of cases. CBR's retrieval process can be divided to two step. The first step is matching step, and the second step is selection step. For selecting base case, new preference heuristics were introduced using similarity concept. Similarity concept has three has three dimensions, i.e. entity similarity, structural similarity, and goal similarity. In this paper, bolt's process planning was selected an application domain. Following the test result, the new preference heuristics were approved as a useful procedure in CAPP.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1991.10a
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• pp.261-267
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• 1991

다품종소량생산의 특징을 갖고 있는 금형공업에서 컴퓨터통합생산시스템(Computer Integrated Manufacturing System;CIMS)의 실현을 위한 중요한 분야의 하나는 부품설계도면으로부터 최종제품을 생산하는데 필요한 공정계획의 자동화, 즉 컴퓨터를 이용하여 공정계획을 자동적으로 생성하는 자동공정계획시스템(Computer Aided Process Planning;CAPP) 기술의 개발이다. 국내외적으로 CAPP분야의 연구는 컴퓨터 지원에 의한 자동화 기술의 급속한 발전과 더불어 지난 20여년 동안에 기계가공품에 관한 CAPP은 약 150여가지가 개발되었으나, 이는 컴퓨터 지원에 의한 설계의 자동화(Computer Aided Design;CAD)나 컴퓨터 지원에 의한 제조의 자동화(Computer Aided Manufacturing;CAM)분야에 비해 상대적으로 저조한 형편이다. 특히 금형을 대상으로 한 CAPP시스템의 개발은 아직 초기단계에 있기 때문에, 본 연구에서는 사출금형을 대상으로 하여 실용성이 있는 공정설계시스템을 개발함을 목적으로 한다. 일반적으로 공정계획은 "소재로부터 제품을 경제적, 효율적으로 생산하는데 필요한 제조공정의 체계적인 결정"이라고 정의할 수 있다. 공정계획은 제품의 종류와 수량, 재료와 부품의 종류, 보유 생산설비와 제조기술의 수준에 따라 다르나, 공정설계(Process Design)와 작업설계(Operation Design)로 구분할 수 있다. 본 연구에서는 공정계획을 광의의 공정설계로 정의하고, 공정설계와 공정계획을 동의어로 통용토록 한다. 기존의 CAPP시스템의 개발에 관한 기본적인 접근방법은 변성형방법(Variant method), 창성형방법(Generative method) 및 자동화방법(Automatic method)이 있다. 이들 CAPP시스템을 개발할 때 사용하는 기법은 크게 5가지- (1) GT(group Technology) 접근기법, (2) Bottom-up 접근기법, (3) Top-down 접근기법, (4) AI와 전문가시스템(Expert System) 접근기법, (5) 컴퓨터 프로그래밍 언어 - 로 분류할 수 있다. 본 연구에서는 전문가시스템 기법을 도입해서 사출금형 공정계획전문가의 지식과 경험을 획득하여 지식베이스를 구축하고, 전문가시스템 셀(shell)중 CLIPS를 이용하여 자동공정계획시스템인 Mold CAPP을 개발하였다.PP을 개발하였다.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.109-118
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• 1999

The objective of this research is to develop an effective inspection planning strategy for sculpture surfaces in OMM(On-Machine Measurement) process. As a first step, effective measuring point locations are determined to obtain optimum results for given sampling numbers. Two measuring point selection methods are suggested in this study based on newly proposed CAD/CAM/CAI integration concept: (1) by the prediction of cutting errors, (2) by considering cutter contact points to avoid the measurement errors caused by cusps. As a next step, the TSP(Traveling Salesman Problem)algorithm is applied to minimize the probe moving distance. Appropriate simulations and experiments are performed to verify the proposed inspection planning strategy in this study, and the results are analyzed.