• 품질경영학회지
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• 제22권4호
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• pp.1-12
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• 1994

각각의 설계인자들의 실험조건에서 얻어지는 특성치들의 분산은 평균에 영향을 받는다. 많은 경우에 평균이 커짐에 따라서 분산이 커지는 경향이 있다. 다구찌가 산포제어인자를 찾기 위해서 제시한 SN 비인 $(SN)_i$ = 10 log ($\bar{y}_{i}^{2}/s_{i}^{2}$) 은 분산이 평균의 제곱에 비례하여 커지는 경우이다. 그런데 분산이 평균의 제곱보다 더 느리게 또는 더 빠르게 커질 수도 있기 때문에 이 논문에서는 간단한 자료분석적 기법에 의해서 그 관계를 추측하여, 합당한 SN 비를 사용할 것을 제시하였고, 평균조정인자를 찾기위한 통계량인 감도 $(S)_i$ 의 통계적 성질들을 논의하였다.

• 한국환경과학회지
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• 제8권3호
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• pp.331-336
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• 1999

The monthly water quality data measured at 14 stations located in the Geum-River watershed were clustered into 2 to 7 clusters. Furthermore, factor analyses were conducted on Gabcheon and Yugucheon to characterize the water qualtiy, based on the information obtained from the results of culster analysis. The results of cluster analysis show that the water quality charactersitic of main stream of the Geum-River is somewhat different from that of substream of the Geum-River. Furthermore, the water quality characteristic of Gabcheon which is expected to have the most serious water quality problems in the Geum-River watershed shows the most different water quality characteristic from Yugucheon. Based ont he factor loadings in each factor, Gabcheon and Yugucheon have their own water quality characteristics. This is mainly because of composite factors such as different population density, industrial activities, and land use conditions in Gabcheon and Yugucheon subwatersheds.

• 품질경영학회지
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• 제30권1호
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• pp.61-73
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• 2002

The Quality Function Deployment(QFD) is a Quality Management technique to maximize customers' satisfaction by reflecting customer requirements into all business processes, including concept definition, product planning, parts planning, process planning, production planning, and sales planning. The basic concept of the QFD is to translate customers' requirements appropriately into engineering characteristics, into parts characteristics, into process characteristics, and into specific requirements and activities in production. In this study, we reviewed and analyzed the application process of the QFD to the development of A2 FATC (Full Automatic Temperature Controller), an automotive component developed and produced by company A. It has been reported that by applying the QFD to the development of A2 FATC, company A. achieved 34% improvement in control robustness quality characteristic, 27% improvement in deviation quality characteristic, and 30% improvement in overall quality characteristics.

• 품질경영학회지
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• 제32권3호
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• pp.109-125
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• 2004

This paper deals with an optimal process control problem in production of hull structural steel plate with high defective rate. The main quality characteristic(dependent variable) is the internal quality(defect) of plates and is dependent on process parameters(independent variables). The dependent variable(quality characteristics) has three categorical ordinal data and there are 35 independent variables(29 continuous variables and 6 categorical variables). In this paper, we determine the main factors and to develop the mathematical model between internal quality predicted probabilities and the main factors. Secondly, we find out the optimal process condition of main factors through analysis of variance(ANOVA) using simulation. We consider three models to obtain the main factors and the optimal process condition: linear, quadratic, error models.

• 품질경영학회지
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• 제27권2호
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• pp.126-142
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• 1999

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. Taguchi parameter design has a great deal of advantages but it also has some disadvantages. The various research efforts aimed at developing alternative methods. 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 suggested by Welch et. al. ( 1990) and studied by others. In these studies, only single quality characteristic was considered. In this paper we propose how to simultaneously optimize multiple quality characteristics using desirability function when we used the combined-array approach to assign control and noise factors. An example is illustrated to show the difference between the Taguchi's product-array approach and the combined-array approach.

• 한국환경과학회지
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• 제16권7호
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• pp.805-811
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• 2007

The purpose of this study was to invesitigate relationship between rainfall water quality and precipitation characteristic during the accumulated rainfall and rainless period. As the results of the analysis, rainfall water quality was improved in the rainfall duration. Correlation coefficients between rainwater quality and accumulated rainfall were $0.88{\sim}0.99$ except $Cl^-$. and that between rainless period and initial rainfall water quality were $0.62{\sim}0.75$. During the Asian dust event, concentration of the turbidity, BOD and electric conductivity were high. Therefore, it shows that the rainfall water quality is effected by atmospheric conditions before the rainfall events.

• 한국경영과학회지
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• 제36권2호
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• pp.15-32
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• 2011

The research for exchange relationship in customer's perspective is meaningful especially in service, considering distinctive characteristics of service operations such as customer participation in the process whereas most of the recent related researches have been focused on employee's interaction with organization, leader, team and customer. In this study for beauty art service, the exchange party's characteristic is defined with beauty salon's reputation, staff's professionalism and customer's self-esteem. Also the exchange relation perception is classified into symbolism and interaction, Then the directional relations on customer's perspective are empirically investigated in the sequential order of the exchange party's characteristics, the exchange relation perception, the relationship quality and behavioral intention. In addition, the study examined the meditation effect via relationship quality between the exchange relation perception and the behavioral intention. Followings are confirmed from the statistical test with structural equation modelling：Symbolism is significantly caused by all of professionalism, reputation and self-esteem in the descending order of effect size whereas interaction is significantly influenced by only professionalism. The exchange relation perception has significant effect on the relationship quality, in turn which significantly affects behavioral intention. The exchange relation perception shows the significant indirect effect meditated by relationship quality and the insignificant direct effect on behavioral intention. This paper concludes with contribution of this study, managerial implication of the research findings and further research issues.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1040-1043
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• 2004

As time goes by, the market demand increases and each LCD panel manufacturing company makes every effort to produce more panels in a limited time. It is necessary to reduce the cost and time of production for the improvement of productivity in manufacturing companies. The increased speed of thin films growth used in the TFT process brings improvement of productivity but it is also accompanied by a drop in display quality due to a characteristic change of the thin film. So in our dissertation, we deal with the increased speed of a-Si layer growth and the proportioned a drop in characteristic quality. We discuss a drop in display quality by a characteristic change of a-Si layer and we propose a counter-plan through panel design improvement. We have already applied our plan to the 15" XGA panel and confirmed the improved result.

• Communications for Statistical Applications and Methods
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• 제8권2호
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• pp.383-394
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• 2001

This paper is a generalization of single and two-level skip-lot sampling plans to n-level. On every skipping inspection of the n-level skip-lot sampling plan, not only the number of consecutive lots to be accepted but also the fraction of lots to be inspected can be freely choosed. The general formulas of the operating characteristic function, average fraction inspected, average sample number and average outgoing quality in n-level skip-lot sampling plan are derived. The operating characteristic curves, average sample number and average outgoing quality of a reference plan, two-level and five-level skip-lot sampling plans are compared.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.381-384
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• 2003

Among digital halftoning methods, error diffusion is a procedure for generating high quality bilevel images from continuous-tone images but blurs the edge information in the bilevel images. To solve the problem, we propose the edge enhanced error diffusion using the edge information of the original images. The edge enchanted weights is computed by adding local characteristic weights and input pixels multiplied a constant. Also, we combined the edge enhanced method with the adaptive error diffusion using human spatial and frequency perception characteristic. The performance of the proposed method is compared with conventional method by measuring the edge correlation. The halftoned images applied the proposed method get more fine quality due to the enchanced edge and better quality in halftoned image. And the detailed edge is preserved in the halftoned images by the proposed method.