• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.847-850
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• 2008

Novel mercaptophenyl carbocyclic C-nucleoside analogue was synthesized via a cyclopentenol intermediate 10, which was prepared using a sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM). Friedel-Crafts alkylation was then used to couple the thiophenol.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1147-1151
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• 2009

The synthetic route of novel 3′-C-methyl carbodine analogue is described. The construction of tertiary alcohol at 3′- position of carbodine analogues was successfully made via sequential [3,3]-sigmatropic rearrangement, ring-closing metathesis (RCM) and stereoselective dihydroxylation reactions starting from ethyl glycolate.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.415-422
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• 2001

Objectives: We aimed to identify the dose-dependent inhibitory effects of Yukmijihwang-tang-Hap-Sabaek-san(YMHSB) and Root cortex of Morus alba L.(RCM) on the mRNA expression of Interieukin(IL)-6, IL-S, granulocyte macrophage colony stimulating factor(GM-CSF) involved in the asthma model. Methods: In this study BEAS-2B cell lines, human epithelial cells, were used. These cells were stimulated by tumor necrosis $factor(TNF)-{\alpha},\;IL-1{\beta}$ and histamine for artificial inflammatory expression. ${\beta}-actin$ messenger RNA(mRNA) was used for the internal standard. After each 24 hours of the YMHSB and RCM treatment, total cellular RNAs were collected by treating RNA zol directly on the living cells. Then the transcriptional activities of IL-6, 8 and GM-CSF were measured by RT-PCR with electrophoresis. Results: In the YMHSB study, the mRNA expression of GM-CSF and IL-8 is significantly inhibited compared to that of control group. But the mRNA expression of IL-6 is not significantly inhibited. In the RCM study, the mRNA expression of GM-CSF and IL-S is significantly inhibited compared to that of control group. But the mRNA expression of IL-6 is not significantly inhibited. Conclusions: This study shows that YMHSB and RCM have dose-dependent inhibitory effects on the mRNA expression of IL-S and GMCSF in human epithelial cells. So these herbal medicines may inhibit the inflammatory process of asthma. Advanced studies are required to investigate the mechanisms of inhibition by herbal medicine in the asthma model.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1289-1292
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• 2003

An efficient synthetic route for preparing novel $4'{\alpha}$-C phenyl branched carbocyclic nucleoside is described. The installation of phenyl group at the $4'$-position of carbocyclic nucleoside was successfully accomplished via a sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM) beginning from simple ketone such as 2-hydroxy acetophenone.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.520-526
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• 2007

본 논문에서는 한국형 틸팅열차의 유지보수 활동을 위해 신뢰성기반유지보수체계를 제안하였다. 열차시스템을 3단계의 교체 부품 단위로 분류하고, 각 단위에 대해 기능블록도를 작성한 후 고장모드 영향 분석을 실시하였다. 각 단위의 심각도를 결정한 후 유지보수 정책을 제안하였으며, 틸팅열차를 위한 유지보수 기준을 정하고, 실제 사례를 제시하였다. 제안된 신뢰성기반유지보수체계는 기존 유지보수 체계와도 호환성을 갖고 있으며, 안전성 향상과 유지보수 활동 효율화에 기여할 수 있다.In this paper, a reliability centered maintenance (RCM) system is proposed to perform maintenance action for Korean Tilting Train. The train system was divided into line replaceable units up to three steps. Functional block diagrams were drawn and failure mode effect analysis for the units was carried out. The criticality of each unit was determined and a maintenance policy was proposed. Maintenance and repair criteria for the tilting train were determined and an example was presented. The proposed RCM system is compatible with the previous maintenance system and contributes to improvement of safety and efficiency of maintenance action.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.243.1-243.1
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• 2003

Extensive efforts in the search of therapeutically useful carbocyclic nucleosides have resulted in a wealth of their synthetic methodologies in racemic and optically active forms. The classical one-directional methods such as linear synthesis and convergent synthesis are the approaches most frequently seen in the literature for the preparation of carbocyclic nucleosides, and their advantages and limitations are well known. (omitted)

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.51-60
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• 2019

In this study, we performed At-site Frequency Analysis(AFA) and Regional Frequency Analysis(RFA) using the observed and climate change scenario data, and the relative root mean squared error(RMMSE) was compared and analyzed for both approaches through Monte Carlo simulation. To evaluate the rainfall quantile, the daily rainfall data were extracted for 615 points in Korea from HadGEM3-RA(12.5km) climate model data, one of the RCM(Regional Climate Model) data provided by the Korea Meteorological Administration(KMA). Quantile mapping(QM) and inverse distance squared methods(IDSM) were applied for bias correction and spatial disaggregation. As a result, it is shown that the RFA estimates more accurate rainfall quantile than AFA, and it is expected that the RFA could be reasonable when estimating the rainfall quantile based on climate change scenarios.

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.755-757
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• 2008

A short and highly efficient synthetic method to prepare synthetically useful tetrahydroindolizinone derivatives from the ring-closing metathesis of N-allyl-5-allyl-5-hydroxylactams is described.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.2
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• pp.69-79
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• 2017

In this study, we developed real-time urban stream discharge forecasting model using short-term rainfall forecasts data simulated by a regional climate model (RCM). The National Centers for Environmental Prediction (NCEP) Climate Forecasting System (CFS) data was used as a boundary condition for the RCM, namely the Global/Regional Integrated Model System(GRIMs)-Regional Model Program (RMP). In addition, we make ensemble (ESB) forecast with different lead time from 1-day to 3-day and its accuracy was validated through temporal correlation coefficient (TCC). The simulated rainfall is compared to observed data, which are automatic weather stations (AWS) data and Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA 3B43; 3 hourly rainfall with $0.25^{\circ}{\times}0.25^{\circ}$ resolution) data over midland of Korea in July 26-29, 2011. Moreover, we evaluated urban rainfall-runoff relationship using Storm Water Management Model (SWMM). Several statistical measures (e.g., percent error of peak, precent error of volume, and time of peak) are used to validate the rainfall-runoff model's performance. The correlation coefficient (CC) and the Nash-Sutcliffe efficiency (NSE) are evaluated. The result shows that the high correlation was lead time (LT) 33-hour, LT 27-hour, and ESB forecasts, and the NSE shows positive values in LT 33-hour, and ESB forecasts. Through this study, it can be expected to utilizing the real-time urban flood alert using short-term weather forecast.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.281-285
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• 2002

Whole plant cultures of Centella asiatica (L.) Urban in vitro were established and the effects of basal media, some macro elements and sucrose concentration on productivity of triterpene glycosides (madecassoside and asiaticoside: M$\varepsilon$A) were investigated. Among the media (MS, B5, RCM) tested, MS and 0.5 RCM medium were the best for plant growth and M$\varepsilon$A production, respectively. However, taking into account the M$\varepsilon$A productivity, B5 medium was superior (M$\varepsilon$A: 14.28 mg/g dry wt.). Major macronutrients of B5 medium adjusted with the concentration of 25 mM KNO$_3$,1 mM NaH$_2$PO$_4$, 1 mM CaCl$_2$ and 1~10 mM MgSO$_4$, caused elevated or optimized levels of M$\varepsilon$A. On sucrose concentration, the highest yields of M$\varepsilon$A were obtained from 6% sucrose.