• Journal of the Korean Chemical Society
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• v.45 no.6
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• pp.549-554
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• 2001

For the development of new COX-2 inhibitor, novel compound were synthesized through induction an arylsulfonyl group to 1-position, an arylcarboxamidyl group to 2-position and an alkyl group to 4-position of L-proline. We started from 4-hydroxy-L-proline, the 4-methylphenylsulfonyl of 1-position was introduced through N-tosylation and the carboxylic acid group was protected by esterification. We sucessfully converted to a various derivatives 4b-d for O-alkyl-(or aralkyl)ation of 4-position using silver oxide as catalysis. The 4-alkyloxy-1-tosyl L-prolines 5b-d were synthesized through base-hydrolysis for the deprotection of carboxylic acid. Final compound 1,2,4-substituted pyrrolidines, 4-alkyloxy-2-phenylcarboxamidyl-1-tosyl pyrrolidines 6a-d were synthesized through the condensation of arylamine with 3 and 5b-d using DCC.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.1-6
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• 2010

The objectives of this study were to i) investigate genetic performance for linear type traits of individual Holstein dairy cows, especially focusing on comparative traits, and to estimate genetic variances for these traits using actual data, and ii) compare genetic performance and improvement of progeny by birth country of the cows. Linear type traits defined with five comparative traits on this study were general stature composite (GSC), dairy capacity composite (DCC), body size composite (BSC), foot and leg composite (FLC), and udder composite (UDC). These traits were scored from 1 to 6 with 1 = poor, 2 = fair, 3 = good, 4 = good plus, 5 = very good and 6 = excellent. Final scores (FS) were also included in this study. Data used was collected from the years 2000 to 2004 by the Korea Animal Improvement Association (KAIA). Only data of more than five tested cows by herd appraisal date and by sires having more than ten daughters were included to increase the reliability of the data analyses. A total of 30,204 records of the selected traits, which was collected from 26,701 individuals having pedigree information were used. Herd appraisal date, year of age, lactation stage (grouped by month), and time lagged for milking (in hours) were assumed as fixed effects on the model. Animal additive genetic effects considering pedigree relationship and residual errors were assumed with random effects. Year of age at appraisal date was classified from one to nine years of age, assigning the value of nine years of age for animals that were greater than or equal to nine years of age. From our results, the estimate for heritability was 0.463, 0.346, 0.473, 0.290, and 0.430 on GSC, DCC, BSC, FLC and UDC, respectively. The estimate for FS heritability was 0.539. The greatest breeding values for GSC were estimated for Canada, with the breeding values for American lines increasing for 10 years starting in 1989 but tending to decrease after that until 2004. For DCC, the breeding values for American and Canadian lines showed similar patterns until 1999, after which the breeding values for the American lines declined sharply. For BSC, data from Korea, Canada and the USA followed similar trends overall except when the breeding values of the American lines decreased starting in 1999. Overall, the methods used to evaluate genetic performance in this study were acceptable and allowed for the discovery of differences by country of genetic origin, likely due in part to the American use of selection indexes based primarily on milk yield traits until methods for evaluating other traits began to emerge.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.3
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• pp.19-25
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• 2008

In this paper, author proposes a novel step-up AC-DC chopper operated with power factor correction(PFC) and with high efficiency. The proposed chopper behaves with discontinuous current control(DCC) of input current. The input current waveform in the proposed chopper is got to be a discontinuous sinusoid form in proportion to magnitude of ac input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control method is simple. In the general DCC chopper, the switching devices are turned-on with the zero current switching, but turn-off of the switching devices is switched at current maximum value. To achieve a soft switching of the switching rum-off, the proposed chopper is used a new partial resonant circuit. The result is that the switching loss is very low and the efficiency of chopper is high.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.5
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• pp.225-230
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• 2008

Netrins are secreted molecules and involved in axon guidance, cell migration and tumor development. Recent studies revealed that netrins perform novel functions in such processes as epithelial development and angiogenesis without operating through the classical netrin receptors, DCC (Deleted in Colorectal Cancer) and Unc5h. In the present study, we investigated the roles of netrin-1 and its receptors in cell spreading of human glioblastoma cells, and found that netrin-1 haptotactically enhanced fibronectin-induced cell spreading and focal adhesion formation in U373 glioblastoma cells. Netrin-1 binding to the U373 cell membrane was blocked by an antibody against ${\alpha}v$ integrin subunit, but not by an anti-DCC or anti-Unc5h antibody. In addition, enhancement of the fibronectin response by netrin-1 was abrogated by a function blocking antibody against integrin ${\alpha}v{\beta}3$. Since the ${\alpha}v$ subunit of the integrin family plays an important role in the pathophysiological aspects of cell migration, including tumor angiogenesis and metastasis, our data provide important insight into the molecular mechanism of netrin function.

• Journal of Korea Port Economic Association
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• v.34 no.4
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• pp.125-140
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• 2018

This study uses daily price data on three major types of crude oil (Brent, Dubai, and WTI) and BDI from January 2, 2009 to June 29, 2018, to compare the relationship between crude oil prices and BDI for rate of change and volatility. Unlike previous studies, the correlation between BDI and crude oil prices was analyzed both the rate of change and variability, VARs, Granger Causality Test, and the GARCH and DCC models were employed. The correlation analysis, indicated that the crude oil price change rate and volatility affect the BDI change rate and that BDI volatility affects the crude oil price change rate and volatility. The relationship between oil prices and BDI is identified, but their correlation is low, which is likely a result of lower dependence on crude oil as demand for natural gas increases worldwide and demand for renewable energy decreases. These trends could result in lower correlations over time. Therefore, focusing on the changing demand for raw materials in future investments in international shipping(real economy) and oil markets and macroeconomic analysis is necessary.

• Applied Biological Chemistry
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• v.41 no.8
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• pp.608-610
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• 1998

To investigate the inhibitory activity of 2-hydroxy-3-amino-4-phenylbutyrate-harboring aminopeptidase N inhibitors, p-nitro-AHPA-peptide derivatives (1 and 2) and an AHPA-peptide derivative (3) were synthesized by chain elongation from C-terminal end using DCC/HOBt as a coupling reagent. The peptides $1{\sim}3$ exerted strong inhibitory activities against aminopeptidase N with $IC_{50}$ values of 1.8, 7.3 and $24.0\;{\mu}g/ml$, respectively, and cytotoxicity on cancer cell lines in vitro.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.980-983
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• 2006

New blue light emitting branched molecules were synthesized by reacting 3,5-bis-(3,5-bis-benzyloxy)- benzoic moiety or 3,5-bis-(3,5-bis-benzyloxy-benzyloxy)- benzoic moiety with biscarbazolyl vinyl biphenyl moiety by dicyclohexylcarbodiimide (DCC) catalyzed esterification. Similar synthetic strategy was also applied to prepare a red light emitting dendrimer. In this paper, we described two blue emitting dendrimers for investigating the effect of the dendronized structures on photoluminescence (PL) and electroluminescence (EL). EL properties of the dendrimers were investigated using heterostructured samples in detalil.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.491-498
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• 1996

울진 3,4호기의 발전소컴퓨터계통(PCS)은 한국형 표준 원전의 컴퓨터 시스템으로 향후 완벽한 시스템으로의 구성을 위해서는 설계 개념의 재검토와 보완이 필요하다. 그 과정의 일환으로 국내 기술진에 의해 이미 상당부분의 기술을 습득한 월성 2,3,4호기의 발전소 제어 컴퓨터계통(DCCS)과 개념적인 비교를 통하여 PCS에서의 설계개선 사항을 구조적으로 제시하고자 하였다. 분석결과 PCS는 실시간 처리가 취약하였고, 몇몇 화면의 구성이 운전원의 요구를 만족시키기 위해 개선되어야 하였다. 또한, DCCS와의 공통적인 취약점으로는 개발환경의 낙후, 데이타 처리능력의 저조, 주변기기와의 데이터 통신에 많은 시간이 소요되며 호환성 및 확장성이 대체로 취약하였다. 이에 대한 대응방안으로는 시스템의 전격적인 교체보다는 부하 분산을 통한 실시간 처리와 점진적인 주변기기의 교체가 바람직하며, 이러한 점진적인 시스템의 교체시 고려사항과 운전원에게 제공되는 화면의 재구성 방안을 제시하였다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.11
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• pp.13-20
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• 2005

For Modern Consumer and Communication Elecronic Devices, Always Error Protecting HW and SW is used. The Core is RS(Reed Solomon) Codec in Galois Field GF($2^8$). Here New 2 to 3 Symbol RS Decoder Design and Encoder design Method using Normalized error position Value is described. Examples are given to show the methods are working well.

• YAKHAK HOEJI
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• v.43 no.3
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• pp.316-319
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• 1999

Chrysin 7-Ο-crotonate was synthesized by condensing crotonic acid with chrysin in organic solvent, tetrahydrofuran (THF) using dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP). Its structure was indentified by NMR, MS, UV, IR etc. We also investigated the physico-chemical properties and set up the quantitative anytical method of this compound. The correlation coefficient of calibration curve measured at the isobestic point (340 nm) on this compound was approximately 0.9994 by absorption spetrophtometry. Detection limit was 1.6ng at S/N=3 by using a RP column by HPLC. The hair growth effect fo chrysin 7-Ο-crotonate on the hair of black mouse (C57BL/6), was carried out using paste method. When its ethanol solution was administered to this black mouse by route of skin, this compound promoted the growth of hair.