• Bulletin of the Korean Chemical Society
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• 제6권5호
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• pp.277-279
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• 1985

Orbital interactions of the types, ${\sigma}-{\pi},\;{\sigma}^*-{\pi},\;{\sigma}-{\pi}^*\;and\;{\sigma}^*-{\pi}^*$ are investigated for the rotamers of ${\alpha}$-X-acetones (X = F and Cl) using STO-3G method of calculation. It was found that the interactions are possible only in gauche forms, and the ${\sigma}^*-{\pi}^*$ interactions are in general greater than the $\sigma-\pi$ interactions due to the greater overlap, in spite of the greater energy gap involved; the greater ${\sigma}^*-{\pi}^*$ interaction causes greater lowering of ${\pi}^*$ level relative to the lowering of ${\sigma}$ in the ${\sigma}-{\pi}$ interaction so that both ${\sigma}-{\pi}^*$ and $n-{\pi}^*$ interactions are enhanced in the gauche forms. The extra stability of the gauche form and the red shift in the $n-{\pi}^*$ transition are thus found to be natural corollaries of the greater ${\sigma}^*-{\pi}^*$ interaction in the gauche forms.

• 충청수학회지
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• 제14권1호
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• pp.61-71
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• 2001

We introduce a new class of ${\sigma}$-coherent frames and show that HA is a ${\sigma}$-coherent frame if A is a ${\sigma}$-frame. Based on this, it is shown that a frame is ${\sigma}$-coherent iff it is isomorphic to the frame of ${\sigma}$-ideals of a ${\sigma}$-frame. Finally we show that ${\sigma}$-COhFrm and ${\sigma}$Frm are equivalent.

• Korean Journal of Mathematics
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• 제14권1호
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• pp.1-5
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• 2006

We will introduce tensor product spectrums on the tensor product spaces. And we will show that ${\sigma}[P(T_1,T_2,{\ldots},T_n)]=P[({\sigma}(T_1),{\sigma}(T_2){\ldots},{\sigma}(T_n)]={\sigma}(T_1,T_2{\ldots},T_n)$.

• 대한산업공학회지
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• 제32권4호
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• pp.268-278
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• 2006

Ten years have passed since Samsung SDI and LG Electronics introduced six sigma. Six sigma spreads on the wide industry areas such as service and public sectors as well as manufacturing industry. Six sigma speaks for Korean enterprise's management innovation now. Then, can we evaluate that Korean enterprise's six sigma has settled down successfully? This study compares Korean enterprise's six sigma with those of Japanese and American enterprises in the view of leadership, project, people, and methodology. We suggest five topics for the successful settlement of six sigma in Korean enterprises; 1) Role of executives and managers should be changed more actively, 2) Strategy-connected projects should be excavated, 3) Utilization and development plan should be made for black belt and master black belt, 4) Six sigma methodology should be advanced, especially DFSS methodology, and finally 5) Several innovation methodology should be integrated.

• 산업경영시스템학회지
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• 제31권3호
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• pp.35-42
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• 2008

In the national economy, rate of service industry is going up to compare with manufacture industry. In spite of getting lots of results to be introduced 6 sigma methodology in Korea, many service companies is suffering with trial and errors. Also 6 sigma isn't settled perfect yet. The reason for that, 6 sigma have been applied to various service without considering. Therefore, this research shows to you right practice plans for service industrial classification to check structural features and difference. So this research seeks methods for revitalization of 6 sigma methodology in service industry after checking existed research, case study for companies to be applied by 6 sigma. As the result, service industry is forecasted to contribute greatly in economic growth and employment enlargement through enlargement of service role in manufacturing industry production as well as by itself.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2007년도 춘계학술대회
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• pp.498-502
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• 2007

The objective of this study aims at proposing a method of Supply Chain Management using Six Sigma. Six Sigma is at the top of the agenda for many companies that try to reduce cost and improve productivity. This paper explains how Six Sigma can be integrated and processed with Supply Chain Management.

• 품질경영학회지
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• 제35권1호
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• pp.97-112
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• 2007

Six Sigma methodology has been evolved since it was first introduced in late 1980's and the number of company which adopts Six Sigma is getting increased. Therefore, it is timely that ire review research papers on Six Sigma extensively. We review 85 papers published in Korea by April 2006 and classify them based on research contents and methodology. We suggest future research issues and fields which can adopt Six Sigma methodology.

• JSTS:Journal of Semiconductor Technology and Science
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• 제9권4호
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• pp.233-239
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• 2009

A mixed CT/DT 2-1 cascaded ${\Sigma\Delta}M$ which includes a first stage CT ${\Sigma\Delta}M$ and a second stage mismatch insensitive two-channel time-interleaved DT ${\Sigma\Delta}M$ is proposed. With this approach, the advantages of both CT and DT ${\Sigma\Delta}Ms$ including high speed operation, inherent anti-aliasing filter, and good coefficient matching can be achieved. The two-channel time-interleaved ${\Sigma\Delta}M$ used in the second stage alleviates the speed constraints of the DT ${\Sigma\Delta}M$, whereas enables better matching between the analog and digital filter coefficients compared to CT ${\Sigma\Delta}Ms$.

• 경영과학
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• 제24권1호
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• pp.147-160
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• 2007

Six Sigma's concept has long been used as an effective way of restructuring the management process of a firm. In literature regarding Six Sigma, a number of successful cases were reported, where Six Sigma based management activities could enhance firm's strategic performance dramatically for year. However, there exist very few researches investigating the effect of Six Sigma on process innovation and quality improvement. Therefore this study propose a research model testing whether Six Sigma innovation could improve process innovation and quality improvement by industrial classification. We collected 332 valid questionnaires from expert in Six Sigma activities, and applied PLS. Empirical results showed that Six Sigma activities could contribute to process innovation and quality improvement.

• 한국식품영양과학회지
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• 제42권6호
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• pp.933-940
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• 2013

본 연구는 urea fractionation을 통하여 포화도 함량이 5.8%, 28.4%, 39.2%, 50.7%, 72.3%인 우지 alcoholysis 반응물을 제조하고, 이를 유상(oil phase)으로 ultrasonic processor 및 고압균질기를 이용하여 emulsion을 제조한 후 이에 대한 유화 안정성과 산화 안정성을 실험하였다. 유화 안정성(ES)을 관찰한 결과 ES값은 46.0(${\Sigma}$SFA5), 39.5(${\Sigma}$SFA28), 32.7(${\Sigma}$SFA39), 32.6(${\Sigma}$SFA50) 및 27.3(${\Sigma}$SFA72)로써 포화도가 낮은 emulsion일수록 높은 안정성을 보였으며, Turbiscan을 이용하여 시료 emulsion의 creaming 및 clarification 특성을 조사한 결과도 ES 결과와 유사하게 나타났다. 고압균질기로 제조한 emulsion 시료에 대하여 30일간 산화특성 및 안정성 연구를 진행한 결과, 제조한 emulsion의 hydroperoxides 함량이 1.880(${\Sigma}$SFA5), 1.267(${\Sigma}$SFA28), 1.062(${\Sigma}$SFA39), 0.342(${\Sigma}$SFA50) 및 0.153(${\Sigma}$SFA72)mg $H_2O_2/mL$로 서로 유의적 차이(p<0.05)를 나타내면서 불포화도가 높은 emulsion 시료일수록 hydroperoxide의 함량이 높았고, TBARS 값은 저장 30일에 6.229(${\Sigma}$SFA5), 6.801(${\Sigma}$SFA28), 6.246(${\Sigma}$SFA39), 4.419(${\Sigma}$SFA50) 및 4.226(${\Sigma}$SFA72) mg TBA/mL로 ${\Sigma}$SFA50과 ${\Sigma}$SFA72가 다른 emulsion 시료보다 유의적으로(p<0.05) 낮은 값을 보이며 산화 안정성이 우수하였다.