• 한국공작기계학회논문집
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• 제13권4호
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• pp.73-78
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• 2004

The conventional SLT(Shear Lag Theory) which has been proven that it can not provide sufficiently accurate strengthening predictions in elastic regime when the fiber aspect ratio is small. This paper is an extented work to improve it by modifying the load transfer mechanism called NSLT(New Shear Lag Theory), which takes into account the stress transfer across the fiber ends and the SCF(Stress Concentration Factor) that exists in the matrix regions near the fiber ends. The key point of the model development is to determine the major controlling factor among the material and geometrical coefficients. It is found that the most affecting factor is the fiber/matrix elastic modulus ratio. It is also found that the proposed model gives a good result that has the capability to correctly predict the elastic properties such as interfacial shear stresses and local stress variations in the small fiber aspect ratio regime.

• 동아시아식생활학회지
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• 제4권3호
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• pp.75-86
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• 1994

The study was conducted to research the desirable method for fermentation of acidic apple beverage in the farmhouse. Step by step fermentation(SSF), complex fermentation after crushing of the fruit(CCF), complex fermentation after slicing of the fruit(SCF) and natural fermentation added yeast only after slicing of the fruit(SYNF) were compared. The brief fermentor for using stationary complex fermentation in the farmhouse was made in this experiment. The ability of acid production, flavor, taste and color were measured by sensory evaluation and mechanical methods. The quality of vinegar by SYNF and SCF were estimated by color, flavor, content, composition of sugar, and organic acids, and which was a suitable fermentation method for the farmhouse. The strains of acetobacter, SYNF-1 and 2 were isolated from the SYNF vinegar, and if has been shown that the SYNF-1 was a main strain in this study.

• 대한화학회지
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• 제30권2호
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• pp.248-258
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• 1986

치환 Oxiranes의 C-C결합 절단에 의한 알켄의 고리첨가 반응의 반응성을 규명하기 위하여 치환기 -CN, $-OCH_3,\;-SCH_3$에 대하여 (1) 치환기가 C-C고리열림 반응에 어떤 영향을 미치고 있는지 (2)치환기가 전이상태와 중간체의 구조에 어떤 영향을 미치고 있는지 (3)carbonyl yildes의 이성화장벽에 어떤 기여를 하고 있는지 (4)고리첨가 반응의 반응성에 치환기가 어떤 효과를 미치는지를 MNDO-SCF-MO법 계산에 의하여 연구하였다. 본 연구에서는 모든 분자의 기하학적 구조를 optimize하였으며 반응경로, 전이상태, 중간체의 계산을 실시하여 반응성과 치환기 효과를 논하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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• pp.93-96
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• 2001

A design methodology of analog circuits for a CMOS stereo 16-bit Δ$\Sigma$ DAC which are suitable for the digital audio applications is described. The limitations of Δ$\Sigma$ DAC exist in the performance of the 1-bit DAC and that of the smoothing filter. The proposed architecture for analog circuits contains the buffer between the digital modulator and the following analog stage and adopts the SCF (switched capacitor filter) and DSC (differential-to-single converter) scheme. In this paper, a guide line for the selection of the filter type for the SCF design in the Δ$\Sigma$ DAC is suggested through the analytical approaches.

• 한국환경보건학회지
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• 제12권2호
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• pp.67-74
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• 1986

The study was carried out to investigate for the property of Bacillus strains, on the native growthed microflora in Korean native soybean paste, and Bacillus strains of the high enzyme producing, were selected and identificated, from the microflora, that is, identificated Bacillus strains beared resemblance to B. subtills, on the colony, appearance was pellicle, surface's spreading, color creamy-thin browned, colony elevation flated, and edge lobated, the identfficated B. subtills strain named for the B. subtilis SCF. For the protease activity of B. subtilis SCF, according to the variation with pH, the pH stability was pH 7~8, and on the its protease activity, optimum temperature was 40$\circ$C, on the other hand, temperature of the highest stability of the protease was 50$\circ$C.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.529-531
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• 1990

Because Filters do both the sampling or Sampled-and-Hold(S/H) operations, it result in the replication of the spectrum of input signal and (unless Nyquist's criterion is satisfied) induce aliasing distortion. In this paper, therefore, we designed AAF(Analog Anti-aliasing Filers) so as to remove high-frequency components from input signal for aliasing distortion prevention before input signal had been processed frequency seletion by filters. and then, researched characteristics of it.

• Mycobiology
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• 제39권4호
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• pp.243-248
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• 2011

The ubiquitin-proteasome system is one of the major protein turnover mechanisms that plays important roles in the regulation of a variety of cellular functions. It is composed of E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 ubiquitin ligases that transfer ubiquitin to the substrates that are subjected to degradation in the 26S proteasome. The Skp1, Cullin, F-box protein (SCF) E3 ligases are the largest E3 gene family, in which the F-box protein is the key component to determine substrate specificity. Although the SCF E3 ligase and its F-box proteins have been extensively studied in the model yeast Saccharomyces cerevisiae, only limited studies have been reported on the role of F-box proteins in other fungi. Recently, a number of studies revealed that F-box proteins are required for fungal pathogenicity. In this communication, we review the current understanding of F-box proteins in pathogenic fungi.

• 대한한의학회지
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• 제23권1호
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• pp.145-155
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• 2002

Objectives : Korean traditional medicinal herbs and some formulas have been used to improve the function of the hematopoietic system. The present research is to examine the effect of DanSamSaMul- Tang(DSSMT) as a biological response modifier related to hemato-potentiating function using bone marrow cell as a testing system. Methods : Mice with leukopenia and thrombocytopenia induced by CTX were treated with DSSMT Extracts. Then we observed cytokines mRNA expression level, the number of CFU-GEMM and BFU-E, and the expression of TPO and SCF in bone marrow cells of mice. Results : In the DSSMT group, the gene expressions of hematopoietic cytokines were increased significantly and the number of CFU-GEMM and BFU-E of this group was significantly increased compared to the group treated only with EPO and IL-3. The expressions of TPO and SCF in the group treated with DSSMT were higher than those of the control group. Conclusions : We showed that DSSMT has a good effect on the hematopoietic system. This could also be used as important research data for Korean oriental medicine about hemato-potentiating.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.219-224
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• 2011

The new MPV type reagent, Al-trifluoromethanesulfonyldiisobutylalane ($DIBAO_3SCF_3$), has been prepared and its reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined, and compared its reactivity with that of Al-methanesulfonyldiisobutylalane ($DIBAO_3SCH_3$) in order to understand the fluorine-substituent effect on its reactivity. In general, the reactivity of $DIBAO_3SCF_3$ appears to be much higher than that of $DIBAO_3SCH_3$, apparently due to the acidity increase by the electron-withdrawing fluorine-substituent. The reagent reduced aldehydes and ketones readily, but showed a perfect selectivity in the reduction of $\alpha,\beta$-unsaturated aldehydes and ketones to produce the corresponding allylic alcohols in an absolutely 100% purity. In addition, the reagent achieved the regioselective cleavage of phenyl- or/and alkyl-substituted epoxides to the less substituted alcohols in a perfect regioselectivity. Moreover, the reagent also showed an high stereoselectivity in the reduction of substituted cycloalkanones to produce the thermodynamically more stable alcohol epimers exclusively.

• 한국초전도ㆍ저온공학회논문지
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• 제21권2호
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• pp.45-49
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• 2019

This paper reports comparison between analytic and numerical simulation approaches for calculation of screening current and screening current induced field in a high temperature superconductor magnet. Bean slab model is adopted to calculate screening current and SCF analytically, while the finite element method numerically. A case study of screening current and SCF calculation are conducted with a magnet, a 7 T 68 mm cold-bore multi-width no-insulation GdBCO magnet built and tested by Massachusetts Institute of Technology Francis Bitter Magnet Laboratory. In this study, we assume the magnet is dunked in liquid nitrogen at 77 K. Furthermore, the simulation results are compared in terms of computation time and accuracy. Finally, discussion on the different methods together with the comparison between the calculations and experiment is provided.