• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.353-357
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• 1992

This paper constitutes the simulator of the serial production line using Extended Petri Nets. We analyze each operations and effect of machine down, calculating the performance measures for improving the capability of manufacturing system. The performance measures are system efficiency, average utilization of machines, average buffer level, and so on. We intend to present the information of the operation states and various problem occurring in the systems.

• Journal of the Semiconductor & Display Technology
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• v.16 no.1
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• pp.29-33
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• 2017

This paper presents a development of vision aligner with three channels for the wafer and plate bonding machine in manufacturing of LED. The developed vision aligner consists of three cameras and performs wafer alignment of rotation and translation, flipped wafer detection, and UV Tape detection on the target wafer and plate. Normally the process step of wafer bonding is not defined by standards in semiconductor's manufacturing which steps are used depends on the wafer types so, a lot of processing steps has many unexpected problems by the workers and environment of manufacturing such as the above mentioned. For the mass production, the machine operation related to production time and worker's safety so the operation process should be operated at one time with considering of unexpected problem. The developed system solved the 4 kinds of unexpected problems and it will apply on the massproduction environment.

• IE interfaces
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• v.9 no.2
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• pp.203-218
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• 1996

This paper deals with a Direct-Input-Output Manufacturing System (DIOMS) which has a number of machine centers placed along a built-in automated storage/retrieval system (AS/RS). During its operations, the storage/retrieval(S/R) machine picks up a pallet from the pickup/deposit port of a machine center and then moves it either to an empty rack opening of the AS/RS for temporary storage or to place it on the port of another machine center for subsequent operation. The machine layout problem in DIOMS is formulated as an integer mathematical programming whose objective is to minimize the total expected distance of the loaded S/R machine during a production period. Recognizing the limit of the exact solution procedure(the Branch and Bound method), two improvement-type heuristics are proposed. One is based on the simulated annealing method and the other the pairwise interchange method. The validity of the heuristics is examined with example problems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.393-397
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• 2001

This paper addresses an Intelligent Agent-based Open Architecture Cell Controller for Intelligent Manufacturing System(IMS). With an Intelligent Agent approach, the IMS will be a independent, autonomous, distributed system and achieve a adaptability to change of manufacturing environment. As the development methodology of Open Architecture Cell Controller, an object-oriented modeling technique is employed for building models associated with IMS operation, such as resource model, product model, and control model. Intelligent Agent-based Open Architecture Cell Controller consists of two kinds of dependant agents, that are the active agent and the coordinator agent. The Active agent is contributed to control components of IMS in real-time. The coordinator agent has great role in scheduling and planning of IMS. It communicates with other active agents to get information about status on system and generates the next optimal task through the making-decision logic and dispatch it to other active agent.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.4
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• pp.23-32
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• 2009

• IE interfaces
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• v.14 no.1
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• pp.20-29
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• 2001

This paper presents a concurrent design approach that deals with manufacturing cell formation and cellular layout in Cellular Manufacturing System. Manufacturing cell formation is to group machines into machine cells dedicated to manufacture of part families, and cellular layout problem determines layout of the manufacturing cells within shop and layout of the machines within a cell. In this paper, a concurrent approach for design of machine cell and cellular layout is developed considering manufacturing parameters such as alternative process plans, alternative machines, production volume and processing time of part, and cost per unit time of operation. A mathematical model which minimizes total cost consisting of machine installation cost, machine operating cost, and intercell and intracell movements cost of part is proposed. A hybrid method based on genetic algorithm is proposed to solve the manufacturing cell formation and cellular layout design problem concurrently. The performance of the hybrid method is examined on several problems.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.1
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• pp.40-46
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• 2011

This paper is to investigate the effects of the asymmetrical support stiffness on the stability of a supercritical driveshaft with asymmetrical shaft stiffness and anisotropic bearings. The equations of motion is derived for a system including a rigid disk, a massless flexible asymmetric shaft, anisotropic bearings and a support beam. The Floquet theory is applied to perform the stability analysis with the variation of the support stiffness, the shaft asymmetry, the shaft damping and the shaft speed. The results show that the asymmetric support stiffness is closely related to the stability caused by primary resonance as well as the supercritical operation. First, the stiffness variation can stabilize the system around primary resonance by weakening the parametric resonance from the shaft asymmetry. Second, it also improve the stability characteristics at a supercritical operation when the support stiffness is not so high relative to the shaft stiffness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.127-133
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• 2014

This paper reviews a finite element model of a wire rope isolator (WRI) via an experimental comparison test. A local operation panel (LOP) mounted on a WRI is modeled using a finite element method. Mode analyses and harmonic analyses are conducted while varying of the thickness of the rope for the WRI. A feasible WRI can be selected considering the reduction of the vibration and the total weight of the LOP system.

• International Journal of CAD/CAM
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• v.2 no.1
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• pp.39-44
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• 2002

This paper presents a structure and architecture of an integrated simulation method (ISM) to meet the requirements of virtual factory engineering (VFE). Combining CAD, VR and discrete event simulation techniques, the ISM provides static and dynamic simulation functions for implementation of VFE throughout the lifecycle. The static simulation can be used to evaluate the factory layout. The dynamic simulation enables us to evaluate ergonomics of factory, process performance of production system, feasibility of production plan and operation of factory, and to train operators safely, which cover the whole VFE lifecycle. The principles of the key techniques of VFE, including virtual factory data management system (VFDMS), static and dynamic simulation, are also discussed. To demonstrate and validate the ISM, a case study has been carried out in an assembly factory.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.4 s.181
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• pp.99-108
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• 2006

Since mold industries are regarded as belonging to three types of bad business, capable young people are reluctant to work in this field. The industries are hard to employ skilled workers who have much experience and knowledge On the mold manufacturing. Thus, effective CAM systems are required for unskilled workers to create process plans and NC data for the manufacturing, and process plans play important roles in the downstream manufacturing processes, such as NC machining, polishing, and final assembly. This study proposes a decision support system that facilitates unskilled workers to easily select high quality NC-data, as well as to increase productivity. The proposed system is assumed to follow a CAM operation scenario that consists of next three steps: 1) identifying several process plans and enumerating feasible unit machining operations (UMOs) from material and part surface information, 2) creating all feasible NC-data based on UMOs using a commercial CAM system, 3) selecting the best NC data among the feasible NC data using four screening criteria, such as machining accuracy, machining allowance, cutting load, and processing time. A case study on the machining of a camera core mold is provided to demonstrate the proposed system.