• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2000년도 추계학술발표논문집 (하)
• /
• pp.1401-1404
• /
• 2000

인간을 대신해서 산업현장을 운영하고 있는 공장자동화 소프트웨어(FMS: Flexible Manufacturing System)가 첨단시대에 발맞추어 다양한 종류로 개발되고 있다. 자동화된 생산라인을 거치는 제품의 품질은 생산기계장치의 품질뿐만 아니라 전반적인 공정을 담당하는 FMS의 성능에도 크게 좌우된다. 본 논문에서 소개하는 설계는 공장자동화 생산설비인 FMS의 품질평가를 지원하는 툴킷이다. 즉, 완성된 제품이 제품개발목적에 적합한지 그 적절성과 제반사항에 대한 평가를 지원한다. 또한 측정과정에서 발견된 오류 및 평가내역을 관리할 수 있도록 하였다. 이러한 기능은 차후 FMS를 개발할 때 관련자가 평가이력을 참조할 수 있도록 함으로써 FMS 품질관리에 도움을 줄 수 있다.

• 대한산업공학회지
• /
• 제18권1호
• /
• pp.169-176
• /
• 1992

In parts assignment problem for FMS, both the parts and the tools required to process the parts are assigned to the machine tools for a specified planning period. This is an important decision-making problem for a short-term production planning of FMS. In this paper, parts assignment problem for FMS was analyzed to determine the optimal plan which has the adaptability to production fluctuation. A mathematical model was developed for determing the parts and the tools required for the machine tools which compose FMS, and the model was analyzed to obtain optimal solution. In addition, the vality and feasibility of the computational algorithm was examined by solving a numerical example.

• 산업경영시스템학회지
• /
• 제21권47호
• /
• pp.35-45
• /
• 1998

Scheduling problem in Flexible Manufacturing Systems(FMS) is complex because of various situation of Manufacturing Systems. Especially, in case of short-term scheduling demanding high efficiency, low cost at short-period, efficient scheduling is a serious problem. To solve this problem, many dispatching rules are developed. But, it leave much to be desired, because real situation in shop floor is complex and real-time scheduling is needed in real manufacturing shop floor. In this paper, search algorithm that allocate different dispatching rules to each machine is presented to complement lack of dispatching rule and develop practical real-time scheduling system. The search algorithm is described in detail. First, algorithm detect machine breakdown, evaluate each dispatching rule. dispatching rules for each machine meeting performance criteria are ranked. The algorithm selects new dispatching nile for bottleneck machine. The effectivenes and efficiency of the mixed dispatching rule and search algorithm is demonstrated.

• 한국시뮬레이션학회:학술대회논문집
• /
• 한국시뮬레이션학회 1998년도 추계학술대회 및 정기총회
• /
• pp.142-146
• /
• 1998

In this paper, we suggests a WIP(work in process) of FMS analysis methods based on the Genetic algorithm. We conjoined both the assignment and the scheduling problem in order to create a new representation scheme for a chromosome and a mutation operators.

• 한국시뮬레이션학회:학술대회논문집
• /
• 한국시뮬레이션학회 1993년도 제3회 정기총회 및 추계학술발표회
• /
• pp.16-16
• /
• 1993

The efficient use of capital intensive FMS requires determination of effective dispatching priority with which the parts of the selected part types are to be inputed into the system. This paper presents a simulation-optimization approach to find an appropriate dispatching priority. The study is based on a detailed simulator for a module-type commercial FMS, Specifically, after presenting the basic configuration and fundamental control logic of the system together with its main characteristics as a special type of a job shop, an algorithm is presented which combines simulated annealing and simulation to explore a dispatching priority of operations that minimizes the total tardiness, Computational performance of the algorithm shows that good solutions can be obtained within a reasonable amount of computations. The paper also compares the performance of the "optimal" or near optimal dispatching priority generated by the proposed algorithm with those generated by standard dispatching rules such as SPT, EDD and SLACK.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
• /
• pp.776-782
• /
• 1995

This paper presents a methodology for development of a heterarchical control system in Flexible Manufacturing Systems (FMS) environment. A Petri net based model is applied for development of control software. A real-time scheduling methodology for the heterarchical system is also developed and it is used as a software entity in the overall architecture. The partition of generic and specific modules in control software development is emphasized. The control system performs its control tasks in two stages: (1) generation of generic control code and distribution of them to each controller entity prior to system execution; (2) generation of specific control code according to job arrival and its process plan. The control software and the scheduling algorithm are evaluated by a simulation program.

• 기계저널
• /
• 제25권2호
• /
• pp.117-121
• /
• 1985

SIMAN의 주요한 논리적 특성은 시뮬레이션프로그램이 시스템 모델부분과 실험부분의 두가지로 구성이 되어 있으며, 일반적인 시스템의 모델링과 분석뿐만 아니라, 자재운반시스템, 로봇 시스템, 제조 셀(manufacturing cell), 플렉시블 제조시스템(Flexible Manufacturing System, FMS)등의 모델링에 유용한 특성을 가지고 있어서 생산시스템의 시뮬레이션에 아주 적합한 시뮬레이션 언 어이다. 또 SIMAN은 대형. 중형 컴퓨터는 물론, 16비트 바이크로컵퓨터에서도 사용이 가능하 다(5). 이 글에서는 SIMAN 시뮬레이션 언어를 사용한 생산시스템의 시뮬레이션에 대한 개념과 방법을 고찰하고, 생산시스템의 시뮬레이션에 관한 간단한 사례를 고찰하고자 한다.

• 제어로봇시스템학회논문지
• /
• 제13권7호
• /
• pp.677-682
• /
• 2007

Concurrent competition for finite resources by multiple parts in flexible manufacturing systems(FMS's) and inappropriate initial marking or net structure of Petri net with share resources results in deadlock. This is an important issue to be addressed in the operation of the systems. Deadlock is a system state so that some working processes can never be finished. Deadlock situation is due to a wrong resource allocation policy. In fact, behind a deadlock problem there is a circular wait situation for a set of resources. Deadlock can disable an entire system and make automated operation impossible. Particularly, an unmanned system cannot recover from such a status and a set of jobs waits indefinitely for never-to-be-released resources. In this paper, we proposed a deadlock prevention method using siphon and trap of Petri net. It is based on potential deadlock which are siphon that eventually became empty. This method prevents the deadlock by the control of transition fire and initial marking in the Petri net. An given example of FMS is shown to illustrate our results with deadlock-free.

• 대한산업공학회지
• /
• 제25권3호
• /
• pp.298-309
• /
• 1999

In this study, we attempt to solve the loading and scheduling problems of an FMS in an integrated manner. We propose an integrated approach and its solution methodologies which can fully exploit the flexibility of an FMS effectively and make decisions about tool allocation, machine selection, and job sequencing simultaneously. The proposed approach consists of two main modules : 'schedule generating module' which makes partial schedules and 'tool-allocation checking module' which investigates the feasibility of tool-allocation for unscheduled tasks. Utilizing two interacting modules, we can finally settle the loading and scheduling problems. Experimental results show that in most cases the proposed integrated approach outperforms existing hierarchical approaches in the scheduling performance and the computational time required. In addition to that, the difference between the two approaches tends to increase when the number of part types and the number of alternative machines increase and the tool constraints become tight. To conclude, the experimental results show that the proposed approach is a viable one for solving practical problems.

• 한국경영과학회:학술대회논문집
• /
• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
• /
• pp.1048-1055
• /
• 2003

This paper proposes a new method of solving integrated problems that consist of several sub-problems in a symmetric multi-layered structure, and also demonstrate the applicability of the method. The proposed method is named Symmetric Multi-layered Coevolutionary Algorithm (SMCA). The SMCA imitates partly the natural process of endosymbiotic evolution, which is a special type of coevolution. The SMCA is applied to the process planning problem in flexible manufacturing system (FMS), taking account of the flexibility of machine, tool, process, and sequence. To do this, SMCA's components are studied and its strategies are developed to improve the performance. The proposed algorithm is compared with the existing ones in terms of solution quality. The experimental results confirm the effectiveness of our approach.