• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.39
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• pp.63-73
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• 1996

With the success of flexible manufacturing systems (FMSs), flexible assembly systems (FASs) have been developed to automate factories further. As in a cellular FMS, a cellular FAS is considered as the most flexible and feasible assembly system configuration Because of the differences between manufacturing and assembly operation, the logic of cell formation and cell layout between a FMS and a FAS is not the same. Since the time for assembly operation is usually relatively short, the transfer time is thus very crucial for the performance of assembly systems. Therefore in assembly systems it is important to reduce the transfer time by sequencing operations efficiently and arranging machines like the sequences. The network-type layout is not only feasible for the machine arrangement based on operation sequences, but it has also layout flexibility. Therefore it is a reasonable layout configuration for cellular FASs. This paper presents a method for the cell layout based on the network-type layout in a cellular FAS design.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1553-1556
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• 1991

This paper deals with a problem on the selection of alternative tools in a flexible manufacturing system (FMS) where a lot of tools are required to produce a large variety of product items. An approach using branch and bound method is proposed to minimize a total number of tools required through the optimal use of the alternative tools. In this approach, tools are initially divided into tool subgroups based on graph theory for the purpose of the effective search of the optimal solution. A small example is also presented to highlight the effectiveness of the proposed approach.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.105-106
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.1-13
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• 1991

This paper describes two FMS, which were developed by SAEIL Heavy Industries. One is FMS for machining of circular parts, that are automobile's axle shafts. This system consists of 13 units, including 7 CNC machine tools. The other is FMS for machining of non-circular parts namely casted or steel block within size of 1.2 X 1.2 X 1.5m. This FMS consists of 8-machining centers, 1-automated warehouse, 2-unmanned Robo Trailers, and computer control room. All systems are functioning satisfactorily and so help greately towards automation of Korean industries.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.2
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• pp.107-118
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• 1994

This research is concerned with production scheduling for a flexible manufacturing cell which consists of two machine centers with unlimited buffer space and a single automatic guided vehicle. The objective is to develop and evaluate heuristic scheduling procedures that minimize maximum completion time. A numerical example illustrates the proposed algorithm. The heuristic algorithm is implemented for various cases by SLAM II. The results show that the proposed algorithm provides better solutions than Johnson's. It also gets good solutions to minimize mean flowtime.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.4
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• pp.75-86
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• 1998

We address the problem of determining the optimal processing times and pallet/fixture allocation in Flexible Manufacturing systems in order to minimize tool cost while meeting throughput targets of multiple part types. The problem is formulated as a nonlinear program superimposed on a closed queueing network of the FMSs under consideration. A numerical example reveals the potential of our approach for significant cost saving. We argue that our model can be Integrated Into the process planning system of an FMS to generate efficient process plans quickly.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1099-1104
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• 1993

The real time control system for FMS(Flexible Manufacturing System) is implemented at this paper. To achieve this goal, the Colored and Timed Petri-Net model is constructed and used to simulate the real time operation of FMS. Using the Colored and Timed Petri-Net model, evaluating any kind of FMS plant is possible. On-line shceduler, intelligent dispatcher, real time monitor and the simulation model of shop floor are contructed using LAN communication, relational database system in this paper. Finally, this real time control system is applied to the FMS/CIM center at Seoul National University.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.7-22
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• 1991

This paper describes two FMS, which were developed by SAEIL Heavy Industries. One is FMS for machining of circular parts, that are automobile's axle shafts. This system consists of 13units, including 7CNC machine tools. The other is RMS for machining of non- circular parts namely casted or steel block within size of 1.2${\times}$1.2${\times}$1.5m. This FMS consists of 8-machining centers, 1-automated werehouse, 2,-unmanned Robo Trailers, and computer control room. All systems are functioning satisfactorily and so help greately towards automation of Korean industries.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.209-213
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• 1998

This study considers flowshop scheduling problem related to flexible maufacturing cell in which consists of two machining centers, robots for loading/unloading, and an automated guided vehicle(AGV) for material handling between two machining centers. Because no machinng center has buffer storage for work in process, a machining center can not release a finished job until the empty AGV is available at that machining center. While the AGV cannot tranfer an unfinished job to a machining center until the machining center empty. In this paper, an new heuristic algorithm is given to find the sequence that minimize their makespan.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.32
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• pp.63-71
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• 1994

The purpose of this paper is to describe an effective cell scheduling system for flexible manufacturing cells. Based on the FMC characteristics, cell scheduling can be defined as a dynamic modified flow shop working in a real-time system. This paper attempt to find the optimal cell scheduling when minimizing the mean flow time for n-job/m-machine problems in static and dynamic environments. Real-time scheduling in an FMC environment requires rapid computation of the schedule.