• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.443-448
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• 1998

With using artificial neural networks (ANNs), an analytical study related to the heated length effect on critical heat flux(CHF) has been carried out to make an improvement of the CHF prediction accuracy based on local condition correlations or table. It has been carried out to suggest a feasible criterion of the threshold length-to-diameter (L/D) value in which heated length could affect CHF. And within the criterion, a L/D correction factor has been developed through conventional regression. In order to validate the developed L/D correction factor, CHF experiment for various heated lengths have been carried out under low and intermediate pressure conditions. The developed threshold L/D correlation provides a new feasible criterion of L/D threshold value. The developed correction factor gives a reasonable accuracy fur the original database, showing the error of -2.18% for average and 27.75% for RMS, and promising results for new experimental data.

• 한국식품영양과학회지
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• 제34권3호
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• pp.351-355
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• 2005

식이섬유의 기능을 가지는 저항전분(HM: HI-MAIZE)과 저항전분에 차전자피를 포함한 탄수화물로 구성된 D-factor를 10% 가하여 제조한 식이섬유(HM-D: HI-MAIZE DIET)의 특성을 비교하기 위하여 glucose 및 bile acid 흡수저해효과 및 장내 세균에 의한 혐기적 발효산물인 단쇄지방산의 함량을 각각 비교하였다 반투막을 이용하여 glucose흡수저해효과를 측정한 결과, HM에 비하여 HM-D의 경우 glucose 저해효과가 다소 우세한 것으로 나타났으며, 투석 막을 통한 glucose 투과는 4시간 경과 시 HM은 77%와 HM-D는 68%를 보였으며, 24시간까지 연장시 glucose는 거의 전부 투과되었다. 투석 막을 이용한 bile acid 흡수저해효과는 HM시료에 비하여 D-factor가 첨가된 저항전분의 경우 bile acid 흡수저해효과가 우수함을 알 수 있었으며, 투석막을 통한 bile acid 투과는 서서히 일어났으며 24시간 경과 시 HM과 HM-D의 경우 65%와 62.3%의 bile acid 투과가 이루어 졌다. 장내 세균에 의한 단쇄지방산 생성은 HM의 경우 217.8mM, HM-D는 264.0mM로 HM-D의 경우 더 많은 양의 단쇄지방산의 생성량을 보였으며, butyric acid 생성 양은 HM-D가 32.7mM로 26.9mM생성량을 보인 HM에 비하여 높았다. 따라서 D-factor첨가에 의해 glucose와 bile acid의 흡수저해 효과가 증가하였을 뿐만 아니라 단쇄지방산의 함량과 butyric acid함량 증가를 보임에 따라 D-factor첨가에 의해 저항전분이 지니는 식이섬유의 기능이 강화되었다.

• Journal of electromagnetic engineering and science
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• 제8권4호
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• pp.139-143
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• 2008

In this paper, a new scheme to calculate the weighting factor of the 2-D isotropic-dispersion finite difference time domain(ID-FDTD) is proposed. The weighting factor in [1] was formulated in free space, so that it may not be optimal in dielectric media. Therefore, the weighting factor was reformulated by considering the material properties and using the least mean square method. As a result, a minimum numerical dispersion error for any dielectric media is guaranteed.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.398-404
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• 2003

Most previous researches for the hybrid composite materials such as FRMLs(Al/AFRP, Al/GFRP) have evaluated the fatigue delamination behavior using the traditional fracture mechanism. However, most previous researches have not generally been firmed yet. Because delamination growth behavior in hybrid composite should be consider delamination growth rate, $dA_D$/da using the delamination shape factors, fs instead of traditional fracture mechanic parameters. The major purpose of this study was to evaluate the relationship between delamination shape factor, fs and delamination growth rate, $dA_D$ . And a propose parameter on the delamination aspect ratio, b/a. The details of the study are as follow : 1) Relationship between crack length, a and delamination width,b. 2) Relationship between delamination aspect ration, b/a and delamination area rate,($(A_D)_{N}(A_D)_{ALL}$. 3) Variation of delamination growth rate, $dA_D/da$ was attendant on delamination shape factors, $fs_1$, $fs_2$, $fs_3$. The test results indicated the delamination growth rate depends on delamination shape factors.

• 중소기업융합학회논문지
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• 제6권3호
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• pp.65-69
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• 2016

백내장이 있는 45~85세 총 119명의 백내장 수술 전후의 굴절이상 변화도를 알아보기 위하여 굴절이상과 각막굴절력을 power vector에 의하여 M, $J_0$, $J_{45}$ 3가지 성분으로 분석하였다. 등가구면 굴절력인 M 성분은 백내장 수술 전 $-0.29{\pm}2.38D$에서 수술 후 $-0.18{\pm}0.69D$로, $J_0$성분은 $-0.34{\pm}0.68D$에서 $-0.05{\pm}0.42D$로, $J_{45}$성분은 $0.11{\pm}0.45$에서 수술 후 $0.02{\pm}0.17$로 변화하였다. 각막평균 굴절력은 백내장 수술 전 $44.11{\pm}1.61D$에서, 백내장 수술 후 $44.20{\pm}1.58D$로, $J_0$성분은 $0.01{\pm}0.50D$에서, $0.08{\pm}0.49D$로 $J_{45}$성분은 $0.02{\pm}0.29$에서, $0.08{\pm}0.49$로 변화하였다. 굴절이상에 대한 수술 전후 상관관계는 $J_0$성분이 가장 높은 상관성이 있는 것으로 나타났고, 각막굴절 성분에 대한 상관관계는 평균 각막굴절력이 가장 높은 상관성이 있는 것으로 나타났으며, 각막굴절력 성분이 굴절이상 성분보다 더 높은 상관관계를 나타냈다.

• Archives of Pharmacal Research
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• 제16권3호
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• pp.209-212
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• 1993

The anti-coagulant activity of ilexoside D isolated from the roots of ilex pubescens Hook. et Am. was investigated in in vivo models of blood coagulation in rats. On oral administration, ilexoside D prolonged the bleeding time and the whole blood recalcified clotting time, but not the plasma recalcified clotting time. In vitor, ilexoside D did not affect the recalciffed clotting times of whole blood, platelet-rich plasma(PRP), and platelet-poor plasma(PPP), while in the presence of tissue factor the compound prologed the reduced proth-rombin times of whole blood, PRP and PPP in the dose-dependent manner. These results indicate that ilexoside D has the anit-tissue factor activity as well as the antithromobotic activity.

• The Korean Journal of Physiology and Pharmacology
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• 제25권1호
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• pp.15-26
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• 2021

Peptides are short chain of amino acids linked by peptide bonds. They are widely used as effective and biocompatible active ingredients in cosmetic industry. In this study, we developed novel peptide mixture and identified its anti-pigmentation effect on melanocytes and keratinocytes. Our results revealed that peptide mixture inhibited melanosome biogenesis through the regulation of microphthalmia-associated transcription factor, a key factor of melanogenesis in melanocytes. And we observed that peptide mixture inhibited melanosome uptake through the reduction of protease-activated receptor 2, a phagocytosis-related receptor in keratinocytes. Furthermore, peptide mixture activated autophagy system resulting in degradation of transferred melanosomes in keratinocytes. The anti-pigmentation effect of multi-targeting peptide mixture was assessed in a human skin equivalent model (MelanoDerm). Melanin contents in epidermal layer were significantly decreased by topical treatment of peptide mixture, suggesting that it can be applied as a novel cosmetics material having a whitening function.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2003년도 International Symposium of Silkworm/Insect Biotechnology and Annual Meeting of Korea Society of Sericultural Science
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• pp.19-22
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• 2003

Chromatin structure plays a critical role in the regulation of transcription. Drosophila GAGA factor directs chromatin remodeling to its binding sites. We found that Drosaphiia FACT, a heterodimer of dSPT16 and dSSRPl, is associated with GAGA factor through its dSSRPl subunit, binds to a nucleosome and facilitates GAGA factor-directed chromatin remodeling. Immunostaining of polytene chromosomes revealed colocalization of GAGA factor and FACT in many specific loci. (omitted)

• Journal of Power Electronics
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• 제12권5호
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• pp.699-707
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• 2012

This paper proposes a single-stage half-bridge electronic ballast with a high power factor using only a single coupled inductor. Compared to conventional high power factor electronic ballasts, the proposed ballast is a simpler circuit with a low cost and a high reliability. The proposed ballast is made up of a power-factor-correction (PFC) circuit and a self-oscillating class-D inverter. The PFC and inverter stages of the proposed ballast are simplified by sharing only a single coupled inductor and two common switches. The proposed PFC circuit can achieve a high power factor and low voltage stresses of the switches. A saturable transformer in the self-oscillating class-D inverter determines the switching frequency of the ballast. Experimental results obtained on a 30W fluorescent lamp are discussed.

• Biomolecules & Therapeutics
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• 제18권3호
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• pp.294-299
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• 2010

In this study, we tried to investigate whether platycodin D significantly affects MUC5AC mucin production and gene expression induced by epidermal growth factor (EGF), phorbol ester (PMA) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) from human airway epithelial cells. Confluent NCI-H292 cells were pretreated with varying concentrations of platycodin D for 30 min and then stimulated with EGF, PMA and TNF-$\alpha$ for 24h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA. The results were as follows: (1) Platycodin D was found to inhibit the production of MUC5AC mucin protein induced by EGF, PMA, and TNF-$\alpha$, respectively. (2) It also inhibited the expression of MUC5AC mucin gene induced by the same inducers. These results suggest that platycodin D can regulate mucin gene expression and production of mucin protein, by directly acting on human airway epithelial cells.