• 분석과학
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• 제26권2호
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• pp.120-124
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• 2013

본 연구에서는 대기오염 및 화산활동에 의한 분출가스의 원거리 가스검출에 제한적으로 사용된 개방형 푸리에 변환 분광 분석기(open path FT-IR spectrometer)를 사용하여 적외선광원을 사용하지 않는 passive mode로 $CO_2$, CO, $SO_2$에 대한 정량 분석을 시도하였다. 표준가스를 이용하여 제작된 적외선흡수 스펙트럼으로 $CO_2$, CO, $SO_2$ 다중 회귀 곡선(MLR)을 사용한 농도 별 검량선 작업 결과, $CO_2$, CO는 결정 계수가 0.90 이상으로 선형성이 좋았으나, $SO_2$는 0.88로 비교적 낮은 선형성을 확인할 수 있었다. 실제 화재 실험을 통하여 3가지 가스에 대해서 측정한 결과 $CO_2$는 높은 농도를 확인하였으나, CO, $SO_2$는 확인되지 않았다. 이 결과를 통해서 적외선 광원 없이 개방형 푸리에 변환 분광 분석기를 활용하여 화재시 배출되는 가스의 원거리측정이 가능함을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1241-1248
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• 2011

Three dimensional quantitative structure-activity relationships (3D-QSARs) between new thiosemicarbazone analogues (1-31) as a substrate molecule and their inhibitory activity against tyrosinase as a receptor were performed and discussed quantitatively using CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indices analysis) methods. According to the optimized CoMSIA 2 model obtained from the above procedure, inhibitory activities were mainly dependent upon H-bond acceptor favored field (36.5%) of substrate molecules. The optimized CoMSIA 2 model, with the sensitivity of the perturbation and the prediction, produced by a progressive scrambling analysis was not dependent on chance correlation. From molecular docking studies, it is supposed that the inhibitory activation of the substrate molecules against tyrosinase (PDB code: 1WX2) would not take place via uncompetitive inhibition forming a chelate between copper atoms in the active site of tyrosinase and thiosemicarbazone moieties of the substrate molecules, but via competitive inhibition based on H-bonding.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2433-2442
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• 2011

The three dimensional quantitative structure activity relationship (3D QSAR) models were developed using Comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA) and docking studies. The fit of Quinazolinone antifolates inside the active site of modeled bovine dihydrofolate reductase (DHFR) was assessed. Both ligand based (LB) and receptor based (RB) QSAR models were generated, these models showed good internal and external statistical reliability that is evident from the $q^2_{loo}$, $r^2_{ncv}$ and $r^2_{pred}$. The identified key features enabled us to design new Quinazolinone analogues as DHFR inhibitors. This study is a building bridge between docking studies of homology modeled bovine DHFR protein as well as ligand and target based 3D QSAR techniques of CoMFA and CoMSIA approaches.

• Journal of the Korean Data Analysis Society
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• 제20권6호
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• pp.2771-2779
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• 2018

The recent financial crises cause the co-movement and transmit the risk across different markets and assets. It is well known that market fear affects the quality of credit in the financial markets. In this context, this study examines the co-movement between the volatility index (VIX) of the Chicago Board Options Exchange (CBOE), or VIX, and six emerging countries' credit default swaps (CDSs), by implementing wavelet coherence. Our research aims at revealing whether the VIX can be used to hedge against the bubble behavior of the CDS market in different investment holding periods (short-run, medium-run, and long-run), as well as whether either market can be used to manage and hedge overall market downside risks. The wavelet coherence results show a high degree of co-movement between the VIX and CDS during the 2007-2009 global financial crisis, across the 16-64 weeks' frequency band. In addition, we observe that the positive correlation between the VIX and the CDS markets, implying that the market turmoil intensifies the co-movement between the VIX and CDS markets.

• Educational Technology International
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• 제9권2호
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• pp.39-56
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• 2008

This paper investigates the relationship between the structural characteristics of a virtual CoP and the measures of social network analysis. Several implications were developed by the results of the study First, the study, based on reviews of both the CoP and SNA literature, identified specific structural measures of SNA; connectedness, geodesic distance, and density. Second, the formal CoP investigated in this study showed greater development that the classic, informal CoP in terms of the structural dimension of a CoP. The results show that those measures of social network analysis provide an illuminating way to better understand the structural properties of CoP's. Implications of the study with some suggestions for future research are provided.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.645-650
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• 2011

The 3D-QSAR study of 2-arylbenzoxazoles as novel cholesteryl ester transfer protein inhibitors was performed by comparative molecular field analysis (CoMFA), CoMFA region focusing (CoMFA-RF) for optimizing the region for the final PLS analysis, and comparative molecular similarity indices analysis (CoMSIA) methods to determine the factors required for the activity of these compounds. The best orientation was searched by all-orientation search strategy using AOS, to minimize the effect of the initial orientation of the structures. The predictive ability of CoMFARF and CoMSIA were determined using a test set of twelve compounds giving predictive correlation coefficients of 0.886, and 0.754 respectively indicating good predictive power. Further, the robustness and sensitivity to chance correlation of the models were verified by bootstrapping and progressive scrambling analyses respectively. Based upon the information derived from CoMFA(RF) and CoMSIA, identified some key features that may be used to design new inhibitors for cholesteryl ester transfer protein.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2739-2748
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• 2009

Hologram and three dimensional quantitative structure activity relationship (3D QSAR) studies for a series of anilinobipyridine JNK3 inhibitors were performed using various alignment-based comparative molecular field analysis (COMFA) and comparative molecular similarity indices analysis (CoMSIA). The in vitro JNK3 inhibitory activity exhibited a strong correlation with steric and electrostatic factors of the molecules. Using four different types of alignments, the best model was selected based on the statistical significance of CoMFA ($q_2\;=\;0.728,\;r_2\;=\;0.865$), CoMSIA ($q_2\;=\;0.706,\;r_2\;=\;0.960$) and Hologram QSAR (HQSAR: $q_2\;=\;0.838,\;r_2\;=\;0.935$). The graphical analysis of produced CoMFA and CoMSIA contour maps in the active site indicated that steric and electrostatic interactions with key residues are crucial for potency and selectivity of JNK3 inhibitors. The HQSAR analysis showed a similar qualitative conclusion. We believe these findings could be utilized for further development of more potent and selective JNK3 inhibitors.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1996년도 제10회 학술발표회 논문개요집
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• pp.166-166
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• 1996

• 한국광물학회지
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• 제12권2호
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• pp.77-90
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• 1999

Characteristics and variations of chemical compositions in Co-rich crusts occurred in the EEZ of the Republic of Marshall Islands were reviewed. Correlation coefficient analysis, hierarchical cluster analysis, and Q-mode factor analysis for 62 samples were done in this study. All data were selected and gathered from the open file report of the cooperative cruise done by United States Geological Survey with Scripps Institute of Oceanography, University of Hawaii or Korea Ocean Research Development Institute. The average of crust thickness. Co content, and Ni content of 62 samples from the 21 seamounts were 30mm, 0.58 wt% and 0.40%, respectively. The mineral phases and associated elements assigned by correlation coefficients, cluster analysis and Q-mode factor analysis are following four. 1) CFA: P, Ca, CO2, Y, Sr: 2) Mn-oxide mineral: As, Mn, Co, Na: 3) Al-silicate mineral: Pd,Si, Al, Cu, Fe: 4) PGE-bearing mineral: Rh, Pt, Ir.

• 한국문헌정보학회지
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• 제56권4호
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• pp.269-284
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• 2022

Exploring research similarity of researchers offers insight on research communities and potential interactions among scholars. While co-authorship is a popular measure for studying research similarity of researchers, it cannot provide insight on authors who have not collaborated yet. In this work, we present novel approach to capture research similarity of authors using citation information. Extensive study is conducted on DATA & KNOWLEDGE ENGINEERING (DKE) publications to demonstrate and compare suggested approach with co-authorship based approach. Analysis result shows that proposed approach distinguishes author relationships that is not shown in co-authorship network.