• Journal of IKEEE
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• v.22 no.4
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• pp.999-1005
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• 2018

This paper proposed a search-based high resolution frequency estimation method in power systme. The proposed frequency estimation method adopts a slope-based adaptive search as a base of adaptive estimation structure. The architectural and operational parameters in this adaptive algorithm are changed using the information from context layer analysis of the signals including a localized full-search of spectral peak. The convergence rate of the proposed algorithm becomes much faster than those of other conventional slope-based adaptive algorithms by effectively reducing search range with the application of the localized full-search of spectrum peak. The improvements in accuracy and convergence rate of the proposed algorithm are confirmed through the performance comparison with other representative frequency estimation methods, such as, DFT(discrete Fourier transform) method, ECKF(extended complex Kalman filter), and MV(minimum variable) method.

• The Mathematical Education
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• v.26 no.2
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• pp.55-61
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• 1988

이 논문에서는 CS-Semistratifiable 공간보다 더 일반화된 공간 Cn-Semistratifiable을 정의 하며 그에 따른 여러가지 성질들을 조사하였다. 위상 공간(X, $\tau$)에 대하여 $\alpha$$\times$$\tau$에서 X의 폐집합족으로의 함수 S가 존재하여 다음 조건들을 만족할 때 공간X는 Cn-Semistratifiable over $\alpha$라 정의한다. a) 임의의 개집합 U에 대하여 U=U{S($\beta$, U) : $\beta$<$\alpha$} b) U, V가 X의 개집합이고 U⊂CV이면 모든 $\beta$<$\alpha$에 대하여 S($\beta$, V)⊂S($\beta$, V)이다. c) 만약 ${\gamma}$<$\beta$<$\alpha$ 이라면 임의의 개집합 U에 대하여 S(${\gamma}$, U)⊂S($\beta$, U)이다. d) X의 수렴하는 net $X_{\beta}$$\longrightarrow$X와 X를 품는 임의의 개집합 U에 대하여 적당한 $\beta$<$\alpha$가 존재하여 X$\in$S($\beta$. U)이고 { $X_{\beta}$}는 S($\beta$, U)안에 eventual하게 들어간다. 위의 정의에 의하여 다음과 같은 성질들이 증명되었다. 1 . Strstifiable over $\alpha$$\longrightarrow$cn-semistratifiable over$\longrightarrow$semistratifiable over $\alpha$ 2, 어떤 공간이 cn-Semistratifiable over $\alpha$이기 위한 필요충분 조건은 그것이 linearly cushioned cn-pairnet를 갖는 것이다. 3. cn-semistratifiable over $\alpha$의 부분공간 역시 cn-semistratifiabie over $\alpha$ 하다. 4. on-semistratifiable over $\alpha$의 유한개의 적공간 역시 cn-semistratifiabie over $\alpha$한다. 5. 폐 cn-semistratifiable over $\alpha$ 부분공간들의 합공간 역시 on-semistrbtifiable over $\alpha$ 하다. 6. 폐연속 net-cevering 함수에 의하여 cn-semistratifiable over $\alpha$ 성질이 보존된다.

• Journal of the Korean Regional Science Association
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• v.35 no.4
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• pp.19-32
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• 2019

Since the 2000s, China has been trying to develop the mid- and western regions and reduce regional disparity between the eastern region and the others by construction of the eight HSR corridors known as 4+4. The high-speed railway is known to have a positive impact on regional economic development by improving accessibility between regions. However, some studies point out that the high-speed railways could worsen regional imbalances. The purpose of this study is to examine the impact of the high-speed railway on regional economic growth and balanced development in China, using the beta-convergence model. In particular, we focused on how the effects of high-speed trains on regional economic development varied depending on the level of development. The analysis was conducted centering on the Shanghai-Chengdu line which is connecting eastern, central and western regions with different levels of development.

• Journal of the Korean Chemical Society
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• v.43 no.5
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• pp.540-546
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• 1999

Solution conformation of cyclo-($Gln^1-Trp^2-Phe^3-{\beta}Ala^4-Leu^5-Met^6$), new NK-2 antagonist in dimethyl sulfoxide solution, has been determined by the use of two-dimensional nuclear magnetic resonance spectroscopy combined with simulated annealing calculations. The peptide exhibited converged structures with the atomic root-mean-square difference for the backbone atoms ($N,\;C^{\alpha},\;C'$) of all residues being 0.02${\AA}$ in the 25 annealed structures. The analysis of the structures indicated that the cyclic peptide has three intramolecular hydrogen bonds between $Met^6NH$ and ${\beta}Ala^4CO$, ${\beta}Ala^4NH$ and $Met^6CO$, $Phe^3NH$ and $Met^6CO$, and contain a type-I ${\beta}$-turn with Gln and Trp and ${\gamma}$-turn with Leu. The addition of an extra methylene group to Gly, i.e. P-Ala residue, may relax some unfavorable restraints in the cyclic backbone structure, hence enabling an additional hydrogen bond, which results in stabilizing one conformation.

• The Korean Journal of Applied Statistics
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• v.12 no.2
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• pp.563-572
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• 1999

수리가능한 시스템에 대한 고장시간이 여러 가지 모형에 대한 연구가 최근들어 신뢰성분야의 학자들에 의해 활발히 이루어지고 있다. 본 논문에서는 수리 가능한 시스템의 고장이 와이블과정을 따라 일어날 경우, 고장 시각 $t_n$에서의 강도함수 $\lambda$($t_n$)의 최우추정량의 분사이 형상모수인 $\beta$의 값에 따라 충분히 큰 n에 대하여 수렴 여부를 밝혔다.

• Korean Security Journal
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• no.57
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• pp.205-230
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• 2018

The purpose of this study is to examine the structural model between servant - transformational leadership, organizational citizenship behavior and organizational performance of private security organizations. The security guards working in private security companies in Seoul and Gyeonggi - do were selected as population, random sampling method. The survey was conducted from September 1, 2016 to November 30. Accoridng to the purpose of the study, this study conducted factor analysis(EFA/CFA), reliability analysis, convergence and discriminant validity analysis, and covariance structure analysis using SPSSWIN 21.0 and AMOS 21.0. The conclusions of this study are as follows. First, servant leadership has a positive (+) effect (${\beta}=.406$) on organizational citizenship behavior statistically at .001 level. Second, transformational leadership has a positive (+) effect (${\beta}=.373$) on organizational citizenship behavior statistically at .001 level. Third, organizational citizenship behavior has a positive (+) effect (${\beta}=.615$) on organizational performance statistically at .01 level. Fourth, servant leadership does not affect the organizational performance statistically (${\beta}=.211$). Fifth, transformational leadership does not affect the organizational performance statistically (${\beta}=.058$). Sixth, organizational citizenship behavior has statistically positive (+) mediation effect (${\beta}=.249$) in the relationship between servant leadership and organizational performance. Seventh, organizational citizenship behavior has statistically positive (+) mediating effects (${\beta}=.230$) on the relationship between transformational leadership and organizational performance. Innovation and Improvement of National Emergency Management System in Korea.

• The Journal of the Petrological Society of Korea
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• v.26 no.1
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• pp.45-54
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• 2017

The characteristics of the rock cleavage in Jurassic Geochang granite were analysed using the distribution of microcrack lengths and spacings. The phases of distribution of the above lengths and spacings were derived from the enlarged photomicrographs(${\times}6.7$) of the thin section. First, the length and spacing-cumulative diagrams for the six directions of rock cleavages were arranged in increasing order($H2{\rightarrow}R1$) on the density(${\rho}$) of microcrack length. The various parameters were extracted through the combination of the above two types of diagrams. The discrimination factors representing the three quarrying planes and three rock cleavages were acquired through the mutual contrast between the values of parameters. The analysis results of the research are summarized as follows. The evaluation for the six directions of rock cleavages was performed using the parameters such as (1) intersection angle(${\alpha}-{\beta}$) and (2) exponent difference(${\lambda}_S-{\lambda}_L$) between two exponential straight lines related to spacing(${\alpha}$, ${\lambda}_S$) and length(${\beta}$, ${\lambda}_L$). The values of parameters(1 and 2) are in order of H(hardway, (H1 + H2)/2) < G(grain, (G1 + G2)/2) < R(rift, (R1 + R2)/2). On the contrary, the values of the above two parameters for three planes are in order of R < G < H. Meanwhile, the direction of convergence between two exponential straight lines was derived. The above direction is compliant to arrangement of the line os' centering around the line ol. The above two lines converge in the direction of the Y-axis when the line ol and line os' occupy the upper region on the left and the lower region on the right, respectively(R-type). On the contrary, the above two lines converge in the direction of the X-axis when the order of arrangement between line ol and line os' is reversed(H-type). Especially, the positive(+) or negative(-) value of intersection angle(${\alpha}-{\beta}$) is determined by the arrangement of two vertical lines. This type of correlation analysis is useful for evaluating the relative strength of rock cleavage and discriminating three quarrying planes.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.279-283
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• 2007

Epoxide hydrolase (EH) gene of Caulobacter crescentus was cloned by PCR and expressed in Escherichia coli. The C. crescentus EH (CcEH) primarily attacked at the benzylic carbon of (S)-styrene oxide, while the CcEH preferentially attacked at the terminal carbon of (R)-styrene oxide, thus leading to the formation of (R)-phenyl-1,2-ethanediol as the main product. (R)-phenyl-1,2-ethanediol was obtained with 85% enantiomeric excess and yield of 69% from racemic styrene oxide via enantioconvergent hydrolysis by using recombinant CcEH as the single biocatalyst.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.144-148
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• 2006

본 연구의 목적은 기존 수위-유량곡선식 개발과정에 내재되어 있던 목적함수 문제와 곡선식 개발과 정에서 대두된 발산과 처리 불능문제를 해결하기 위해서 새로운 형태의 관계식$(Q=p(h-e)^{\beta}-{\gamma})$과 비선형 매개변수 추정방법을 이을 제안하고 이러한 신개념의 수위-유량곡선식 산정모형을 개발하는데 있다. 기존 수위-유량곡선식은 기존수위-유량자료를 log변환하여 산정된 목적함수는 저수위에 비하여 고수위 부분에 잘못된 유량 값을 추정하는 문제를 갖고 있다. 기존의 발산 문제는 영유량 수위 매개변수 e를 찾고 추정된 식의 목적함수을 수렴하는 동안 매개변수 ${\beta}$가 비정상적으로 커지는 것이다. 이상의 두 가지 문제는 제어변수 ${\gamma}$를 도입하고 목적함수, $min{\sum}w(i)(Q-\hat{Q})^2$를 도입함으로서 개선 할 수 있게 되었다. 본 연구에서는 물리적 분석과 민감도 분석을 통하여 수위-유량곡선식에서 매개변수 ${\gamma}$의 영향이 e의 영향과 같음을 보였다. 또한 개발된 WinCARD 시스템은 기존의 목적함수에 의한 추정오차와 새롭게 제안된 목적함수의 개선사항을 상호 비교할 수 있게 하였다. 본 개발프로그램은 기존 수위-유량곡선식의 적합도를 평가하고, 하천유량 산정을 위한 신개념의 수위-유량곡선식을 개발하는데 활용될 수 있다.

• Journal of the Korean Chemical Society
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• v.48 no.2
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• pp.161-170
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• 2004

A series of ${\gamma}$-aminobutyric acid-derived, potent human cytosolic phospholipase A$_2$ inhibitors have been prepared from acyl cyanophosphoranes and amine derivatives in a convergent manner. The ${\alpha}$-keto amide functionalities in the inhibitors have been introduced as electrophilic fragments via direct coupling reactions between the labile ${\alpha},{\beta}$-diketo nitriles and ${\gamma}$-aminobutyric acid t-butyl ester derivatives at -78 $^{\circ}C$ in moderate to good yields.