• 한국기계가공학회지
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• 제14권6호
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• pp.90-97
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• 2015

Optimization of multi-quality characteristics in injection molded parts is very important, but it is sometimes difficult for part/mold designers. The objective of this study is to develop a practical design methodology for optimizing two-quality characteristics of injection molded parts. To attain this end, we developed a new design-range reduction algorithm based on Taguchi's orthogonal arrays for two characteristics. Then, the algorithm was integrated with commercial injection-molding simulation tools. A feature of the proposed methodology is that it allows field-designers unfamiliar with general optimization methods to be able to apply the methodology to their design problems with ease. Finally, we have applied the proposed design methodology to optimization of weldlines and deflections in an actual bezel model. The results show the usefulness of this methodology.

• Journal of Information Technology Applications and Management
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• 제23권3호
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• pp.71-86
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• 2016

This paper proposes a new software quality model composed of a hierarchy of software quality views and three software quality characteristics models. The software view hierarchy is composed of two levels : end view and means view at the first level, contingency view and intrinsic view as sub-views of means view. Three software quality characteristics models are activity quality characteristics model, contingency quality characteristics model, and intrinsic quality characteristics model, which correspond to end view, contingency view, and intrinsic view respectively. This paper also reclassifies characteristics of ISO/IEC 25000 series SQuaRE's software product quality model according to the proposed software quality model. The results illustrate clearly the shortcomings of SQuaRE's product quality model and how to overcome them. First of all, most of SQuaRE's product characteristics should be redefined and conceptually clarified according to the views on which they are really rested. Much more characteristics should be supplemented too. After that, rigorous empirical researches will become relevant. Causal relationships between activity quality characteristics and characteristics of means view should be empirically researched.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.879-882
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• 2004

Two-phase flow exists in many industrial components. Characteristics of two-phase flow have been studied by many researchers; however, a further study of the two-phase is required for flow-induced vibration. Characteristics of two-phase flow were measured by force sensor at the end of a vertical pipe. The predominant frequency of fluctuation was obtained for various speeds of flow pattern. A correlation to slug frequency for horizontal flow was obtained by Heywood & Richardson (1979), while Legius et al (1997) for vertical flow. A coefficient based on the correlation is estimated and then compared to the existing ones. The existing empirical formulations for average void fraction were proposed by Wallis (1969), Zuber et al (1967) and Ishii (1970). In the present result, flow parameters, such as flow quality and real velocity, are evaluated with void fraction.

• 품질경영학회지
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• 제29권4호
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• pp.170-178
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• 2001

The objectives of this paper are to introduce some characteristics of two-dimensional concept of quality and to find out the possibility of the application of two-dimensional quality concept for improving the service quality. The concept was applied to small & medium-sized foreign language Institute. In order to select some service quality dimensions and decide attractive qualify factors among numerous factors, factor analysis and frequently analysis were used. The result. is that all quality factors in empathy dimension are identified as attractive quality factors. This implies that customization program is necessary in small & medium-sized foreign language institutes for improving their competitiveness. However, all quality factors in tangibles dimension are identified as must-be quality factors.

• 대한안전경영과학회지
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• 제3권3호
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• pp.213-220
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• 2001

This paper presents the interrelationship between software quality character and engineering attributes. The software quality characteristics and subcharacteristics are excerpted from IS0/IEC 9126 standards, and the engineering attributes are from Deutsch and Willis〔4〕. Based on the previous studies a subjective judgement, trisected interrelationship(strong, medium, weak) bet these two groups are derived. The results are summarized in a table, and can be used as a quick reference guide to the software quality engineering application such as quality evaluations for software products, selection of key engineering attributes for high-quality software production, and so forth.

• 한국초지조사료학회지
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• 제12권1호
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• pp.19-25
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• 1992

This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

• 한국초지조사료학회지
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• 제12권1호
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• pp.19.1-19.1
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• 1992

This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

• 품질경영학회지
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• 제24권2호
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• pp.142-157
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• 1996

Robust design in industry is an approach to reducing performance variation of quality characteristic values in products and processes. In the Taguchi type robust design, the product array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. In this paper, for the combined array approach to assign control and noise factors, we propose how to simultaneously optimize multiple quality characteristics. Two examples are illustrated to show the difference between the product-array approach and the combined-array approach.

• 동아시아식생활학회지
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• 제20권5호
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• pp.720-726
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• 2010

This study was investigated for quality characteristics of cabbage from two geographic origins during fermentation of kimchi at $4^{\circ}C$ for 50 days. The pH of kimchi made from cabbage of domestic and imported was decreased with increased fermentation period, while total acidity was increased with increased fermentation period In two samples, the best pH was when it became the 10th of the fermentation period. All fermentation period, vitamin C content is gradually increasing, decreasing after the maximum value. And 40 day fermentation period expect that kimchi made using domestic cabbage, kimchi made using imported cabbage had a higher content of vitamin C contents. Hardness and chewiness of two samples decreased during fermentation. Change of hardness was lowed kimchi made using domestic cabbage. The results of sensory evaluation, texture and overall acceptability were higher in both the kimchi made using domestic cabbage.

• 한국통신학회논문지
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• 제31권10B호
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• pp.936-944
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• 2006

인터넷통신 서비스업체는, 최상위 기업경영 성과지표중 하나인 고객만족지수 향상을 위해, 전사적 품질경영을 전개하고 있다. 이와 관련, 고객만족지수와 연관성이 강한 기업내부 주요 인터넷통신 네트워크 품질특성에 대한 관리의 필요성이 제기되고 있다. 본 연구는, 인터넷통신 네트워크 품질특성 모니터 링을 위한 I-MR 관리도 활용체계를 제안한다. 네트워크 품질특성이 관리상태인지 모니터링하고, 네트워크 품질특성이 이상변동을 보이면, 이상원인 조사시점을 결정할 목적으로, 일정간격 연속 측정시점별; 1) 개별측정값 (individual measurements): 및 2) 연속 2개 개별측정값간 이동범위 (moving ranges)를 이용한 통계적 품질관리 체계인 I-MR 관리도를 활용한다. 사례분석에서는, 이상변동 발생시점에서 이상원인이 완전히 제거된다는 가정에 근거하여, 네트워크 품질특성의 실현가능한 치대 기대품질개선율이 계산된다. 인터넷통신 2개 Service A. B. Service별 7개 네트워크 품질특성 대상, 11개 측정지역의 기대품질개선율 평균, 표준편차를 분석, 1-MR 관리도 활용체계의 효과를 검토한다. 사례분석 결과, 기대품질개선율 범위는 다음과 같다. 1) Service A, (1) 평균 (0.31%-11.44%), (2) 표준편차 (9.82%-71.10%); 2) Service B, (1) 평균 (0.29%-17.64%), (2)표준편차 (8.05%-60.59%). 그러므로, 본 연구에서 설계·제안된 I-MR 관리도 활용체계는, 네트워크 품질특성의 평균 산포 개선 및 관리상태 유지에 효과적일 것으로 판단된다.