• Journal of the Korea Safety Management & Science
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• v.2 no.3
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• pp.185-195
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• 2000

Increased complexity of products and their manufacturing processing demans higher quality control and monitoring than ever before. Therefore, flexible automatization or flexible manufacturing systems (FMS) offer numerous advantages over alternative manufacturing methods. In this state, a in-process monitoring is one of the important flexible automatino system. And as use of NC and CNC machine tool has been increasing, cutting work has automating and it is necessary to develop the automatic production system combined a couple of machine tool. Thus, in this paper to search examination it can measure the tool wear and the tool life and can be more practical research subject.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3232-3238
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• 2010

As flexible manufacturing systems (FMSs) are highly automated and required flexibility to satisfy market need, dispatching rules are constrained by specific environments of manufacturing systems such as mechanical failures, absence of employees, and lack of spare parts. In this paper, an ontology-based knowledge approach is proposed to improve efficiency of system through adapting suitable dispatching rules, considering context in a FMS shop floor, which consists multiple manufacturing cells. the multi-agents monitor manufacturing system status and job so that it figures out a dispatching rule considering context. To demonstrate the proposed approach, a proof-of-concept prototype system has been implemented in the $JADE^{TM}$ platform and Protege to make OWL DL ontology.

• Journal of the Korea Safety Management & Science
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• v.9 no.2
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• pp.113-122
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• 2007

Recently, the strategy of the age of limitless competition for existence of manufacturing company appears for the enhancement of productivity through the automatic system, the reduction for the cost for standardization and the decision making process for the information system. Especially the critical success factors in manufacturing company can be summarized for the establishment of production visibility through the production management, material & work-in-process management, the establish of the flexible manufacturing system for the changed order priority and the establish of the quality system for improvement of product and process quality. The existing production management systems supply only simple information about production results on real time, can delay quick decision making. And it can prevent acquiring the information about various customer needs and the communication problems with other systems. In this paper, it will show MES system, a solution for the problems of existing production management systems. And through a case study of D company, it will reveal improvement effect on shipment error using MES system and economic analysis for MES itself.

• Korean Management Science Review
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• v.8 no.1
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• pp.27-39
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• 1991

This paper describes the instructional flexible manufacturing system(FMS) laboratory facility at Virginia Polytechnic Institute(VPI) which is directed at problems and issues in the design, implementation and control of computer integrated manufacturing systems. It begins with a configuration and an operational description of FMS laboratory facilities. Next, relevant curricula in manufacturing systems design and control, which can use the FMS laboratory for instructional purpose, are introduced, A computer simulation can be used as an excellent tool for analysis prior to implementation of FMS as well as an on-going improvement tool. A brief survey of simulation languages is lastly included.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.377-380
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• 1996

Most manufacturing systems are large and complex. It is natural to divide the control into a hierarchy consisting of a number fo different levels. Each levels is characterized by the length of the planning horizon and the kind of data required for the decision making process. This paper describes an approach for the incorporation of Maintenance times into a hierachical scheduling for a failure prone flexible manufacturing system. The Maintenance should not be performed too often because of the resulting reduction of capacity. The machine failure and preventive maintenance are considered simultaneously.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.8
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• pp.706-712
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• 2002

In general, a deadlock in flexible manufacturing systems (FMSs) is caused by a resource limitation and the diversity of routings. However, the deadlock of industrial controllers such as programmable logic controllers (PLCs) can occur from different causes compared with those in general FMSs. The deadlock of PLCs is usually caused by an error signal between PLCs and manufacturing systems. In this paper, we propose a deadlock detection and recovery (DDR) algorithm to resolve the deadlock problem of PLCs at design stage. This paper employs the MAPN (modified automation Petri net), MTPL (modified token passing logic), and ECC (efficient code conversion) algorithm to model manufacturing systems and to convert a Petri net model into a desired LD (ladder diagram). Finally, an example of manufacturing systems is provided to illustrate the proposed DDR algorithm.

• Korean Management Science Review
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• v.4
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• pp.60-75
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• 1987

This paper introduces the outlines of the state-of-the-art in studying FMSs using analytical queueing network models. These include Jackson networks, reversible networks and approximate models of non-product-form networks. the focus is on identifying the major features of models as they relate to the operational characteristics of FMSs. Prescriptive models concerning the optimal design and/or operational control of FMS networks are also discussed. We notice that the presentation of materials in this paper basically follows Yao and Buzacott, On Queueing Network Models of Flexible Manufacturing Systems(FMSs), invited and published on Queueing Systems, Theory and Application 1(1986). For other analytical models of FMSs, refer to Buzacott and Yao, Flexible Manufacturing Systems : A Review of Analytical Models, Management Science 32, No.7(1986).

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.81-89
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• 1997

This study is concerned with the scheduling problems in flexible manufacturing systems(FMSs). The scheduling problem in FMSs is a complex one when the number of machines and jobs are increased. Thus, a heuristic method is recommended in order to gain near-optimal solutions in a practically acceptable time. The purpose of this study is to develope a machine and AGV dispatching algorithm. The proposed dispatching algorithm is a on-line scheduling algorithm considering the due date of parts and the status of the system in the scheduling process. In the new machine and AGV dispatching algorithm, a job priority is determined by LPT/LQS rules considering job tardiness. The proposed heuristic dispatching algorithm is evaluated by comparison with the existing dispatching rules such as LPT/LQS, SPT/LQS, EDD/LQS and MOD/LQS. The new dispatching algorithm is predominant to existing dispatching rules in 100 cases out of 100 for the mean tardiness and 89 cases out of 100 for the number of tardy jobs.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.46
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• pp.19-32
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• 1998

This paper addresses the processing route of parts and economic design in flexible manufacturing systems (FMSs) employing AGVs for Transport. Parts are processed through several workstations according to operation sequences. The machine of each workstation can do multiple operation functions. The operation stage of a part can be processed in several workstations, which are non-identical in functional performance. The objective of this paper is to determine the processing route of parts, number of machines at each workstation, number of vehicles. The model is assumed that the operation stage of parts can be processed at the only one among several available workstations. Parts are transported by automated guided vehicle system(AGVS). The decision criteria is to minimize the sum of processing cost, travel cost, operating cost. A model formulation is represented. A solution algorithm is suggested by using mathematical programming and simulation technique, and a numerical example is shown.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.2
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• pp.31-43
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• 2019

In this study, polymer elastic bumps were fabricated for the flexible electronic package flip chip bonding and the viscoelastic and viscoplastic behavior of the polymer elastic bumps according to the temperature and load were analyzed using FEM and experiments. The polymer elastic bump is easy to deform by the bonding load, and it is confirmed that the bump height flatness problem is easily compensated and the stress concentration on thin chip is reduced remarkably. We also develop a spiral cap type and spoke cap type polymer elastic bump of $200{\mu}m$ diameter to complement Au metal cap crack phenomenon caused by excessive deformation of polymer elastic bump. The proposed polymer elastic bumps could reduce stress of metal wiring during bump deformation compared to metal cap bump, which is completely covered with metal wiring because the metal wiring on these bumps is partially patterned and easily deformable pattern. The spoke cap bump shows the lowest stress concentration in the metal wiring while maintaining the low contact resistance because the contact area between bump and pad was wider than that of the spiral cap bump.