• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.152-160
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• 1996

This paper focuses on development and evaluation of a performance management algorithm for IEEE 802.4 token bus networks to serve large-scale integrated manufacturing systems. Such factory automation networks have to satisfy delay constraints imposed on time-critical messages while maintaining as much network capacity as possible for non-time-critical messages. This paper presents a network performance manager that adjusts queue capacity as well as timers by using a set of fuzzy rules and fuzzy inference mechanism. The efficacy of the performance management has been demonstrated by a series of simulation experiments.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.1
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• pp.24-35
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• 2013

A cell formation approach based on cluster analysis is developed for the configuration of manufacturing cells. Cell formation, which is to group machines and parts into machine cells and the associated part families, is implemented to add the flexibility and efficiency to manufacturing systems. In order to develop an efficient clustering procedure, this paper proposes a cluster analysis-based approach developed by incorporating and modifying two cluster analysis methods, a hierarchical clustering and a non-hierarchical clustering method. The objective of the proposed approach is to minimize intercellular movements and maximize the machine utilization within clusters. The proposed approach is tested on the cell formation problems and is compared with other well-known methodologies available in the literature. The result shows that the proposed approach is efficient enough to yield a good quality solution no matter what the difficulty of data sets is, ill or well-structured.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.195-203
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• 2016

Heavy metals have been analyzed on the non-woven from the 24 kinds of wet wipes and 8 kinds of mask packs. The following materials used in the non-woven according to each product are: rayon+polyester for the 12 wet wipe products, rayon+PET for the 5 wet wipe products, and rayon, cotton, rayon+polyester+cotton, pulp+polypropylene for the rest of the wet wipe products. No further information on the materials was found on the 3 wet wipes and 8 mask packs. However, polyester may be applied for the non-woven in wet wipes, because PET is part of the polyester group. The heavy metals analysis in the 24 kinds of wet wipes and 8 kinds of mask packs revealed the following: arsenic was found from $47.14{\pm}1.13$ to $71.75{\pm}1.64{\mu}g/L$ on the 3 products, the amount of nickel in the 2 products were $261.26{\pm}5.14$ and $1,242.63{\pm}43.71{\mu}g/L$, $53.69{\pm}1.45$ and $103.52{\pm}2.02mg/L$ on the 2 mask packs. It was also revealed that lead was detected from $7.23{\pm}0.32$ to $55.67{\pm}1.46{\mu}g/L$ on the 6 wet wipes, antimony was ranged from $187.86{\pm}5.24$ to $19,558.35{\pm}3,537.30{\mu}g/L$ on the 12 wet wipes, and $5.25{\pm}0.25$ and $8,936{\pm}55.22{\mu}g/L$ on the 2 mask packs. No cadmium, mercury, or thallium were detected from all the products. A high concentration of antimony might come from antimony trioxide, which was used as a catalyst when manufacturing the polyester. Therefore, it is strongly recommended that a non-woven used for cosmetic purposes should not use heavy metals as a catalyst when manufacturing, and it's important to clarify which materials are used in non-woven.

• Korean Business Review
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• v.14
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• pp.169-187
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• 2001

In the recent efficiency study became accomplished generally a listed company, the efficiency study of small manufacturing industry is deficient. The purpose of this study analysis efficiency of small manufacturing industry by using the DEA model. DEA model is non-financial approach method to measure relative efficiency by input factors and output. The panel data from 1996 to 1999 are used for the analysis. The relative mean-efficiency can be summarized as follows. The wholesale trade and commission trade manufacturing industry 68.99%, communication equipment manufacturing industry 60.58%, food products and beverages manufacturing industry 91.05%, motor vehicles, trailers and semitrailers manufacturing industry 85.80%, basic metals manufacturing industry 88.96%, pulp, paper and paper products manufacturing industry 96.53%, chemical and chemical products manufacturing industry appeared with 78.67%. The results is expected to provide the empirical evidence useful to enhancing the competitiveness of manufacturing industry in korea.

• Advances in nano research
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• v.12 no.2
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• pp.151-165
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• 2022

Micro-scale serpentine structure fibers are widely used as flexible sensor in the manufacturing of micro-nano flexible electronic devices because of their outstanding non-linear mechanical properties and organizational flexibility. The use of melt electrowriting (MEW) technology, combined with the axial bending effect of the Taylor cone jet in the process, can achieve the micro-scale serpentine structure fibers. Due to the interference of the process parameters, it is still challenging to achieve the precise deposition of micro-scale and high-consistency serpentine structure fibers. In this paper, the micro-scale serpentine structure fiber is produced by MEW combined with axial bending effect. Based on the controlled deposition of MEW, applied voltage, collector speed, nozzle height and nozzle diameter are adjusted to achieve the precise deposition of micro-scale serpentine structure fibers with different morphologies in a single motion dimension. Finally, the influence mechanism of the above four parameters on the precise deposition of micro-scale serpentine fibers is explored.

• Journal of Korean Society for Quality Management
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• v.38 no.1
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• pp.10-19
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• 2010

The competitive strategies of the Korean manufacturing companies have changed from the "cost leadership" strategy in the early developing stage since 1960's to the "stuck in the middle" position since 1990's in the face of emerging new cost leaders as the Chinese companies. The data on the strategic contents of the Korean manufacturing companies show that their strategies are seeking the value innovation through not only quality improvement but also cost reduction altogether rather than selecting one on the trade-off relation between the both competitive dimensions. Their strategic actions seem to be seeking the operational efficiencies through all the value chain activities rather than the strategic effectiveness by selecting and focusing on the specific competitive dimension, which is considered as a typical strategic approach. Their strategy seems to be non-strategic in the general sense. But their non-strategically looking behaviors can be reasonable enough for their sandwiched competitive position between the global quality leaders and following cost leaders. This paper explains why their strategies can be right through the theoretical explanations by using the quality-price elasticity approaches for the consumer behaviors. We can call their strategic activities as the value innovation strategy.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.21-29
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• 2013

The short circuit and overload is presented by main cause of electrical fire. However, 85% of the fan directly connected the outlet box without switch in total 110 fans as a research in manufacturing industries. In installation direction of vertical type fans which was placed on the horizontal surface, only 39 vertical type fans were placed on vertical surface and 71 fans were placed on the horizontal type. The installation direction of the fans warns of the risk of the fire hazard due to the motor stall to the user manual of the maker. However, it is the representative nonconformity example of construction which the people or builder disregards. In addition, the condition of ground connection with the earth leakage prevention was investigated in grounding of 5 fans, non-grounding of 105 fans. The double insulation structure is generally used for small fan and it can't connect ground wire as electric plug of non-grounding type. However, industrial iron fan needs ground wire for electric leakage and to protect against electric shock.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.35-38
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• 2004

Global competitive pressures are asking industrial companies to find the best way to meet their customer's requirements, reduce the costs of products, and increase productivity. Quality improvement has been proposed and implemented as a primary means of achieving these purposes. The quality improvement usually includes a goal of reducing the costs due to poor quality. While these costs of poor quality (COPQ) are not known precisely, they are known to be very high. Also, they may be underestimated by the hidden costs due to non-value activities, such as potential lost sales, costs of redesign due to quality reasons, and extra manufacturing costs due to defects, etc. In any manufacturing or service operation, all actions and resource expenditures of a company should be focused on creating value for customers. Any activity or resource of not creating the value for customers could be regarded as waste, which consequently causes the COPQ. Some companies did use dashboards to understand and identify value added or non-value added activities in order to reduce or eliminate wastes. These dashboards must be properly designed to consider inherent differences in manufacturing or service operations among business organizations. In addition, a structured quality improvement program such as the Six Sigma must support these dashboards. In this paper, a case study of designing dashboards for evaluating and reporting the COPQ in business units is presented.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.117-139
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• 1999

This paper is concerned about the hybrid tandem configuration as the design of the automated guided vehicle system(AGVs). The hybrid tandem configuration is that the manufacturing system is divided into several non-overlapping zones, workstations of each zone are linked by network configuration including loop. That is, the manufacturing system is divided into several non-overlapping small size networks, and at most two automated guided vehicles can be available in each network. The transit point is located at proper point between adjacent networks. The parts are transported to workstations in other network through the transit points. One of the objective functions in dividing into the hybrid tandem configuration is to minimize the maximum travel time of the divided networks, and other is to minimize the total travel distance of parts moved to workstations in other networks for the next processing. The model formulation is presented, and a numerical example is shown. Also, the performances of system for the hybrid tandem, tandem and network configuration are compared through the simulation. The results of this research will contribute to the development of material handling systems in the manufacturing system. Also, it will be applied in determining the transportation area of transportation vehicles and the number and size of the transportation fleet in the transportation problem of logistics management.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.137-146
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• 2011

The main objective of the present paper is to conduct a depth analysis of the structural relationship among cooperation of manufacturing corporations, their development of new products and performance in view of an empirical study. The findings of this study could be summed up as follows: First, from the analysis of relationship between cooperation of manufacturing corporations and development of new products, it was found out that there is a positive relationship among such factors of new product development as development process, organizational culture and substructure when cooperation among corporations becomes intensive. Second, the analysis of relationship between development of new products and financial outcomes showed that the factors of new product development like organizational culture and substructure do influence financial performance, while the development process don't. Third, in terms of relationship between factors of new product development and non-financial performance, it was analyzed that non-financial performance can be affected by such factors of new product development as development process, organizational culture and substructure.