• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.8
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• pp.23-32
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• 1993

This paper presents a decomposition method to evaluate the performance measures of the serial production lines with unreliable machines and finite buffers. This method is to decompose the transfer line into a set of two machine lines for analysis. Bases on this approximation method, we consider nonhomogeneous lines. In such lines, the machines may take the different lengths of time performing operations on parts. A new transformation is employed in order to replace the line by a homogeneous line. The approximate transformation enables one to determine parameters of performance such as production rate and average buffer levels, and it also shows better application for a large class of systems.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.509-514
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• 2002

This paper studies on the noise reduction for a small automobile DC Motor (a window motor) using the 6 sigma process. The application of 6 sigma process suggested reliable and valuable statistical data for the quality of the DC motor at the production line. In the measurement step in 6 sigma process, the FMEA(Failure Mode Effect Analysis) were used for the detection of noise sources. The application of 6 sigma process gave not only the improving method for the quality of the DC motor but also the confidence of improvement itself since it was done on the basis of the test results for a number of DC motors at the production line. Consequently the 6 sigma process was proved very effective for the noise reduction at the production line.

• Journal of Welding and Joining
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• v.20 no.6
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• pp.45-45
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• 2002

This study is a middle report on the development of intelligent spot welding monitoring technology applicable to the production line. An intelligent algorithm has been developed to predict the quality of welding in real time. We examined whether it is effective or not through the In-Line and the Off-Line tests. The purpose of the present study is to provide a reliable solution which can prevent welding defects in production site. In this study, the process variables, which were monitored in the primary circuit of the welding, are used to estimate the weld quality by Hidden Markov Model(HMM). The primary dynamic resistance patterns are recognized and the quality is estimated in probability method during the welding. We expect that the algorithm proposed in the present study is feasible to the applied in the production sites for the purpose of in-process real time quality monitoring of spot welding.

• Journal of Welding and Joining
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• v.20 no.6
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• pp.769-775
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• 2002

This study is a middle report on the development of intelligent spot welding monitoring technology applicable to the production line. An intelligent algorithm has been developed to predict the quality of welding in real time. We examined whether it is effective or not through the In-Line and the Off-Line tests. The purpose of the present study is to provide a reliable solution which can prevent welding defects in production site. In this study, the process variables, which were monitored in the primary circuit of the welding, are used to estimate the weld quality by Hidden Markov Model(HMM). The primary dynamic resistance patterns are recognized and the quality is estimated in probability method during the welding. We expect that the algorithm proposed in the present study is feasible to the applied in the production sites for the purpose of in-process real time quality monitoring of spot welding.

• Journal of the military operations research society of Korea
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• v.28 no.2
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• pp.116-124
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• 2002

In just-in-time production systems, U-shaped production lines rather than traditional straight lines are often adopted since they have some advantages. The advantages of U-lines over straight lines are that the workstations required can be reduced and the necessary number of workers can be easily adjusted when the demand rates are changed. In this paper, we present a new genetic algorithm(GA) to minimize the number of workstations primarily and improve the work relatedness secondarily in the U-line production systems. Also, a new heuristic method is presented according to the work related factors and characteristics of U-line balancing. Some major aspects of the proposed GA are discussed, with emphasis on representation, decoding and evaluation function. Extensive experiments are carried out on well-known test-bed problems in the literature to verify the performance of our algorithm . The computational results show that our algorithm is a promising alternative to existing heuristics.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.12 no.19
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• pp.73-78
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• 1989

This paper concerns the production model that the Automatic Guided Vehicles(AGVs) is used as transporters in assembly line. The model suggests that assembly parts may inter the beginning of the line in multiple units instead entering one unit at a time. Costs are occured in proportion to the number of vehicle on the line and job flow time. Here, the objective of this model is to determine the number of vehicle to minimize the total cost for M products production. Theoretical results are proved which lead to the development of algorithm for solution search. The solution search procedure is illustrated by a numerical example.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.76-76
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• 1995

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.2
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• pp.1-8
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• 2014

The automobile manufacture is a typical integrated assembly production that the numerous parts are committed sequentially to the assembly line. In this type of automobile manufacture, WBS (white body storage) and PBS (paint body storage) are operated to adjust the production sequence and to buffer. Starvation (impossibility of production owing to the insufficient supply) or blocking (impossibility of production owing to the over capacity) could occur in some chance, hence, both storages (WBS, PBS) are integrated as a prevention. This system is called integrated storage. In this paper, we suggest the simulation model of 'WBS-PBS integrated storage' and methodology of operation considering both 'Color grouping' and 'Option leveling.'

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.4
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• pp.359-365
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• 2003

This paper describes the on-line readymixed concrete production system using CAN network, which is a leading industrial control network. The CAN network interface circuits for moisture sensor and load cell sensor we designed for CAN network of readymixed concrete production system, respectively, and also the method for networking 2-states devices such as limit switch and lamp is suggested. The operating status of a overall remicon production system is monitored, and also the system is controlled with host computer through the network. The CAN network interface method is applied to the real readymixed concrete production system to verify the performance of proposed method.

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.277-282
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• 2012

A Smart TV device is either a television set with integrated internet capabilities or a set-top box for television that offers more advanced computing ability and connectivity than a contemporary basic television set. In recent years, there has been a popularity rose up on Smart TV (Smart Television) usage at home. This paper present the intelligent production status boards using features and functions of smart TV in shop floor. With the proposed status boards, we can reduce installation and operating costs of the existing production status boards. In addition, This article present the system that can line monitoring without equipments as CC TV.