• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.473-476
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• 2005

Today's manufacturing industry is facing challenges from advanced difficult-to-machine materials (WC-Co alloys, ceramics, and composites), stringent design requirements (high precision, complex shapes, and high surface quality), and machining costs. Advanced materials play an increasingly important role in modem manufacturing industries, especially, in aircraft, automobile, tool, die and mold making industries. The greatly-improved thermal, chemical, and mechanical properties of the material (such as improved strength, heat resistance, wear resistance, and corrosion resistance), while having yielded enormous economic benefits to manufacturing industries through improved product performance and product design, are making traditional machining processes unable to machine them or unable to machine them economically. In this paper, mechanical characteristic evaluation test of fine powder type WC-Co alloy was accomplished to obtain clear data for miniaturized special die parts machining with high reliability and high quality.

• Journal of Korean Society for Quality Management
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• v.22 no.3
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• pp.34-53
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• 1994

Taguchi's robust design methodology has focused only on a single performance characteristic or response, but the quality of most products is seldom defined by a characteristic, and is rather the composite of a family of characteristics which are often interrelated and nearly always measured in a variety of units. The multiple performance characteristics problem is how to compromise the conflicts among the selected levels of the design parameters for each individual performance characteristic. In this paper, the modified desirability function using SN ratio which can be optimized by univariate technique is proposed and a parameter design procedure to achieve the best balance among several different response variables is developed We reanalyze two existing case studies by the proposed method and compare these results with ones by the sum of SN ratios and the expected weighted loss.

• The Journal of Information Systems
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• v.14 no.1
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• pp.197-226
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• 2005

Recently, internet as well as internet banking are growing rapidly. Most banks in Korea provide internet banking services for customers. Internet banking became a major trend in the financial marketplace. There are a few empirical research in this area. Although quality of internet banking service is an important concept, there is a lack of theory-based empirical research in this area. Therefore, this paper is aimed at finding whether service quality of internet banking influence customer satisfaction, and whether characteristic of internet banking user influence relationship between customer satisfaction and service quality of internet banking. Furthermore, this paper identify whether customer satisfaction influence customer loyalty. The research model proposed thirteen hypothesis and tested empirically. A total of 269 responses were received from internet banking users and analyzed. The analyses showed partial support for the affirmative effect of customer satisfaction and characteristic of internet banking user. But the relationship between customer satisfaction and customer loyalty is significant. Implications of these findings are that internet banking sites should concentrate on providing a high quality of banking services; information, trust, ease of use, and security of system and thereby strengthen customer loyalty.

• Journal of Korean Society for Quality Management
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• v.12 no.2
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• pp.15-24
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• 1984

Since W.A. Shewhart (1931) developed the quality control method using the control chart, many theoretical and empirical works about such an analytical method have been done. However there are two major methods relating to the control chart analysis; the conventional 3 sigma control method and the warning limit method which has been suggested as a modification of the former. The conventional 3 sigma method requires to take a remedial action only when a quality characteristic is beyond the control limit (3 sigma). However, once a quality characteristic is over the control limit, searching and repairing an assignable cause requires time consuming job and high costs. Therefore if we set the warning limit between the central line and the control limit, we will be able to take remedial measures before too late. In spite of its advantage, much attention has not been paid to use the control chart with warning limit in Korean industries. The main object of this study is to examine improvement of quality and productivity when the control chart with warning limit is used.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.287-296
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• 1998

We often have multiple quality characteristics to develop, improve and optimize industrial processes and products. It is not easy to find optimal control factor setting when there are multiple quality characteristics, since there will be conflict among the selected levels of the control factors for each individual quality characteristic. In this paper we propose a desirability function approach and devise a scheme which gives a systematic way of solving multiple quality characteristic problems. A numerical example is provided.

• Journal of Korean Society for Quality Management
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• v.23 no.2
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• pp.28-42
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• 1995

For quality improvement, Taguchi emphasizes the reduction of variation of the quality characteristic, Taguchi has used the signal-to-noise ratios for achieving minimum dispersion of the quality characteristic with its location adjusted to some desired target value ${\tau}$ Lim(1994) proposes a reasonable SN ratio based on a linking relationship of the variance and mean through simple data analysis technique. In this paper we investigate the efficiency of those two SN ratios and variance stabilizing transformations through Monte Carlo Simulations.

• Journal of Korean Society for Quality Management
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• v.25 no.4
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• pp.57-70
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• 1997

Consider a production system where all manufactured products are screened through automatic inspection equipment. The products for which the measured value of quality characteristic is larger than the lower screening specification limit (SL) and smaller than the u, pp.r screeing specification limit(SU) are accepted. Those smaller than SL are reworked and those larger than SU are excluded from the process. Assuming that the quality characteristic is normally distributed with known variance, this paper suggests cost models which involve inspection cost, production cost, rework cost, exclusion cost and quality cost, and presents the methods of finding the optimal values of the screening specification limits and the process target. Numerical example is given to demonstrate the a, pp.icability of the cost models suggested in this paper.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.47
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• pp.101-112
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• 1998

Recently, researchers show growing interest on product quality characteristic dependence and designing acceptance sampling plans under the quality dependence. This research intends to resolve a few theoretical and practical questions for better application of acceptance sampling when the quality characteristic of product items exhibits a statistical dependence and samples are inspected according to the production order. In this research, a mathematical programming model is developed for the economic modeling of sampling plans based on two evaluation criteria : the average outgoing quality(AOQ) and the average total inspection cost. An efficient solution procedure is then proposed using the functional structure of the two evaluation criteria and the procedure is numerically illustrated.

• Journal of Integrative Natural Science
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• v.6 no.1
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• pp.39-45
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• 2013

Robust design is an approach to reducing performance variation of quality characteristic values in quality engineering. Taguchi has an idea that mean and variation are handled simultaneously to reduce the expected loss in products and processes. In the Taguchi parameter design, the product-array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined-array approach, was studied. In these studies, only single quality characteristic (or response) was considered. In this paper we propose how to simultaneously optimize for multiple quality characteristics (or multiresponse) using desirability function when we used the combined-array approach to assign control and noise factors.

• Journal of Korea Game Society
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• v.10 no.3
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• pp.73-82
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• 2010

The Metadata are used for the reuse of core information, distribution and management, protection of copyright and prevention of overlapping investment. Serious game consists of multi-hierarchial multimedia data. And quality information is very important for selection according to the purpose of the game. In this paper, we designed the serious game metadata schema, including multi-media characteristic information and measurable quality information. This study will lay the groundwork for the development of metadata system which can provide serious game users with reliability through quality information, and with compatibility through multi-media characteristic information. Furthermore, we hope this study will be helpful to stable growth in serious game industry.