• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.1-10
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• 1990

Polysilane derivatives are attracting considerable attention as a new class of material since 1980. The preparation methods of low molecular weight, cyclic, and high molecular weight polysilane derivatives are described, and also photochemistry characteristics for silicon-silicon single bond and for the nature of the substituent on silicon backbone are discussed. Polysilanes may be used as a precursors to silicon carbide fiber, as photoresist in microelectronics, as photoconductor, and as photoinitatior for free radical polymerization.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.115-117
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• 1997

본 논문에서는 유도전동기의 적응 비선형 제어에 대해 논한다. 제어 목적은 회전자저항의 불확실성에도 불구하고 유도전동기의 속도 및 자속을 분리하여 제어하는 것이며, 이를 위해 백스테핑(Backstepping) 기법을 사용한 비선형제어기와 회전자 저항 추정기를 결합한다. 제안된 적응제어시스템은 내부의 모든 변수가 유계(Bounded)되어 있다는 점에서 안정하며, 더불어 그 개선된 성능을 모의실험을 통해 보인다.

• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.355-358
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• 2010

Inductively coupled low temperature plasmas with oxygen, argon, mixture of oxygen and argon, and nitrogen have been used to modify polycarbonate(PC) films at the various process conditions. All plasma treatments generally had a tendency to increase the surface roughness of PC regardless of process conditions. The treatment of oxygen plasma showed the highest value in the surface roughness and mostly enhanced the generation of oxygen containing polar groups as much as 43% in comparison of untreated PC. The contact angle of untreated PC decreased from $82.31^{\circ}$ to the lowest value of $9.17^{\circ}$ after oxygen plasma treatment. The increase of RF delivered power had an effect on the rapid reduction of contact angle, but gas flow rates did not effect to reduce contact angles so much.

• Journal of the Korean Data and Information Science Society
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• v.18 no.2
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• pp.327-344
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• 2007

Ridge partial least squares regression (RPLS) is a regression method which can be obtained by combining ridge regression and partial least squares regression and is intended to provide better predictive ability and less sensitive to overfitting. In this paper, explicit expressions for the shrinkage factor of RPLS are developed. The structure of the shrinkage factor is explored and compared with those of other biased regression methods, such as ridge regression, principal component regression, ridge principal component regression, and partial least squares regression using a near infrared data set.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1583-1587
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• 2015

Bile acids are endogenous metabolites that aid in the digestion and absorption of ingested fat and fat-soluble vitamins. However, high concentrations of deoxycholic acid (DCA) in the colon are associated with high incidence of colorectal cancer. In the present study, the binding of persimmon extracts to DCA in order to decrease inflammatory stress induced by DCA in a small intestinal epithelial cell line, Caco-2, was investigated. Young and ripened persimmons were extracted with distilled water (DW), ethanol, and acidic ethanol. Further, DW extract residue was re-extracted with acidic ethanol. Of the obtained extracts, acidic ethanol extract of young persimmon showed the highest bile-acid binding capacity. Moreover, acidic ethanol extract of young persimmon significantly inhibited nitric oxide production in Caco-2 cells stimulated with DCA and prevented significant reduction of trans-epithelial electric resistance. Based on these results, acidic ethanol extract of young persimmon can be used as a functional ingredient to enhance gastrointestinal health.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.4
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• pp.165-173
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• 1998

Analytical solutions to predict the movement rate of submerged mound are derived using the convection coefficient and the joint distribution function of wave heights and periods. Assuming that the sediment is moved onshore due to the velocity asymmetry of Stokes' second order nonlinear wave theory, the micro-scale bedload transport equation is applied to the sediment conservation. The nonlinear convection-diffusion equation can then be obtained which governs the migration of submerged mound. The movement rate decreases exponentially with increasing the water depth, but the movement rate tends to increase as the spectral width parameter, $ u$ increases. In comparison of the analytical solution with the measured data, it is found that the analytical solution overestimates the movement rate. However, the agreement between the analytical solution and the measured data is encouraging since this over-estimation may be due to the inaccuracy of input data and the limitation of sediment transport model. In particular, the movement rates with respect to the water depth predicted by the analytical solution are in very good agreement with the estimated result using the discritization technique with the hindcast wave data.

• Proceedings of the Korean Statistical Society Conference
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• 2002.11a
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• pp.169-174
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• 2002

본 연구는 k개 지수분포 모수들의 기하평균에 대한 베이지안추정 방법을 제시하였다. 이를 위해 Tibshirani가 제안한 직교변환법으로 비정보적 사전확률분포를 도출하여 모수들의 결합사후확률분포를 유도해 내었으며, 이 분포 하에서 가중 몬테칼로 방법을 사용하여 기하평균을 추정하는 절차를 제안하였다. 모의실험과 실제자료의 예를 통해 제안된 베이지안 추정의 유효성 및 효용성을 보였으며, 본 연구에서 제안한 사전확률분포가 전통적인 포함확률을 기준으로 볼 때, Jeffrey의 사전확률분포 보다 더 유효한 추정을 함을 보였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2124_2125
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• 2009

본 논문은 COS 활선 교체 작업시 발생할 수 있는 전기적인 위험성에 대한 연구를 수행한 것으로 현장특성을 최대한 고려하여 시험하였다. 시험결과, 일반적으로 절연체로 생각되는 COS 애관 및 결합애자에서도 전위가 유도됨을 확인하였으며, 활선작업 시 발생할 수 있는 감전에 대한 경로분석 및 인체에 대한 영향을 검토하였다.

• Journal of Biomedical Engineering Research
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• v.5 no.2
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• pp.143-148
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• 1984

비접합성 골절의 치료를 위한 전기적인 방법으로는 관혈적이 방법, 부분적으로 관혈적인 방법, 비관혈적인 방법 들이 있는데, 비관혈적인 방식은 다른 방법들과는 달리 수술 등 외과적 처기 등이 필요하지 않을뿐더러 환자에게도 가장 안전한 방식이다. 본 논문에서는 유도 결합 현상을 이용한 반관혈적인 전기 자기 자극기를 설계, 제작하였으며, 임상 실험 겨과 좋은 결과를 보이고 있다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.239-240
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• 2002

유해 대기오염물질에 대한 수용 모델링을 위해 대규모의 분진시료에 대한 분석이 필수적이나 현재로서는 미미한 실정이다. 대규모의 분진시료를 대상으로 미량금속을 분석하기 위해 기존 국내 연구에서 사용된 XRF, ICP-AES, PLXE 분석법 대신 검출 한계가 매우 낮고 재현성이 뛰어난 중성자 방사화 분석법(INAA)과 플라스마 분광법(ICP-MS)을 이용하여 대기오염분야에의 적용성을 평가하는 것은 매우 유용한 연구일 것으로 판단된다. (중략)