• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.6C
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• pp.384-390
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• 2011

The paper derives formulas for the mean-squared error distortion and resulting signal-to-noise (SNR) ratio of a fixed-rate scalar quantizer designed optimally in the minimum mean-squared error sense for a Gaussian density with the standard deviation ${\sigma}_q$ when it is mismatched to a Laplacian density with the standard deviation ${\sigma}_q$. The SNR formulas, based on the key parameter and Bennett's integral, are found accurate for a wide range of $p\({\equiv}\frac{\sigma_p}{\sigma_q}\){\geqq}0.25$. Also an upper bound to the SNR is derived, which becomes tighter with increasing rate R and indicates that the SNR behaves asymptotically as $\frac{20\sqrt{3{\ln}2}}{{\rho}{\ln}10}\;{\sqrt{R}}$ dB.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1056-1059
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• 1997

Thyristor-Controlled Series Compensation (TCSC) is expected to be applied in transmission systems to achieve a number of benefits. TCSC can provide such assistance for stability, as well as helping to direct flows onto desired transmission paths. This paper describess a TCSC model which can be used for typical transient and oscillatory stability studies. Also included is a discussion on relevant information to extend the modeling detail of the TCSC for use stability analysis.

• Journal of Korea Technology Innovation Society
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• v.8 no.2
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• pp.860-885
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• 2005

This study relates to develop a quantitative method through which promising technology-based business items can be discovered and selected. For this study, we utilized patent trend analysis, technology-industry concordance analysis, and keyword co-occurrence analysis of US patents. By analyzing patent trends and technology-industry concordance, we were able to find out the emerging industry trends : prevalence of bio industry, service industry, and B2C business. From the direct and co-occurrence analysis of newly discovered patent keywords in the year, 2000, 28 promising business item candidates were extracted. Finally, the promising item candidates were prioritized using 4 business attractiveness determinants; market size, product life cycle, degree of the technological innovation, and coincidence with the industry trends. This result implicates that reliable discovery and selection of promising technology-based business items can be performed by a quantitative, objective and low- cost process using knowledge discovery method from patent database instead of peer review.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.33-38
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• 1980

This experiment was investigated for purpose of the clearfying the proper temperature and time needed to preserve the lactobacillus fermented products. The results obtained in this experiment were as follows; 1. The number of microorganisms in the lactobacillus fermented products were almost the same as the FAO value. 2. Microorganisms were stable at $4^{\circ}C$ but unstable at $15^{\circ}C$ and $25^{\circ}C$ in the passing of the time. 3. The range of PH changed was from 3.5 to 4.0. 4. The turbidity of the products was more changeable in groups A, B and D than in groups C and E.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.804-807
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• 1996

This paper addresses the small-signal stability and control problems associated with a Static Var Compensator and its power system stabilizer. The major emphasis is on determination of suitable location for SVC arid stabilizer signal tuning through eigenvalues and frequency response techniques. To determinate of suitable location for SVC, this paper used transfer function residues. Adequate oscillation damping is achieved by the use of stabilizing signals, designed through frequency response techniques and added to SVC. The study system is Benchmark System.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1059-1063
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• 1998

Regiospecific total syntheses of (±)-11-deoxy-4-methoxy-10-oxo-βrhodomycinone (21a) and (±)-11-deoxy-1-methoxy-10-oxo-β-rbodomycinone (21b) are described. 2-(2-Bromoethyl)-1,3-dioxane (6) was transformed to naphthalenone 12, which was condensed with (phenylsulfonyl)-isobenzofuranone 13 to afford 7,8-dihydro-9-ethyl-6-hydroxy-4-methoxynaphthacen-5,12-dione (15). Epoxide 16 prepared from olefinic compound 15, reacted with HF/Pyr (7:3) to give 17. Dihydroxylation of 17 with t-BuOK/P(OMe)3/O2, selective cis-diol protection of mixed compounds 18 with phenylboronic acid in toluene, separation of cis-boronate 19 and trans-diol 20 by column chromatography on silica gel, and cleavage of the boronate group of 19 with 2-methylpentane-2,4-diol in acetic acid completed the construction of 21.

• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.856-862
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• 2019

A series of thienopyrimidine compounds (6Aa-g and 6Ba-d) were synthesized and characterized by NMR spectroscopy and mass spectrometry. These compounds (6Aa-g and 6Ba-d) potently inhibited STAT3 expression induced by IL-6 in a dose-dependent manner with $IC_{50}$ values of $5.73-0.32{\mu}M$. Among the prepared thienopyrimidine derivatives, 6Aa, 6Ab, 6Ba and 6Bc significantly suppressed the phosphorylation of STAT3 and ERK1/2 stimulated by IL-6 in Hep3B cells. Furthermore, the synthesized compounds might be useful remedies for the treatment of inflammatory diseases by inhibiting the action of IL-6.

• Bulletin of the Korean Mathematical Society
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• v.56 no.1
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• pp.45-56
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• 2019

The aim of this paper is to investigate the problems of meromorphic functions sharing values concerning periodicities and shifts. In this paper we prove the following result: Let f(z) and g(z) be two nonconstant entire functions, let $c{\in}{\mathbb{C}}{\setminus}\{0\}$, and let $a_1$, $a_2$ be two distinct finite complex numbers. Suppose that ${\mu}(f){\neq}1$, ${\rho}_2(f)<1$, and f(z) = f(z+c) for all $z{\in}{\mathbb{C}}$. If f(z) and g(z) share $a_1$ CM, $a_2$ IM, then $f(z){\equiv}g(z)$. Moreover, examples are given to show that all the conditions are necessary.

• Bulletin of the Korean Mathematical Society
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• v.59 no.3
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• pp.757-780
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• 2022

In this article, we study the weak and extra-weak type integral inequalities for the modified integral Hardy operators. We provide suitable conditions on the weights ω, ρ, φ and ψ to hold the following weak type modular inequality $${\mathcal{U}}^{-1}\({\int_{{\mid}{\mathcal{I}}f{\mid}>{\gamma}}}\;{\mathcal{U}}({\gamma}{\omega}){\rho}\){\leq}{\mathcal{V}}^{-1}\({\int}_{0}^{\infty}{\mathcal{V}}(C{\mid}f{\mid}{\phi}){\psi}\),$$ where ${\mathcal{I}}$ is the modified integral Hardy operators. We also obtain a necesary and sufficient condition for the following extra-weak type integral inequality $${\omega}\(\{{\left|{\mathcal{I}}f\right|}>{\gamma}\}\){\leq}{\mathcal{U}}{\circ}{\mathcal{V}}^{-1}\({\int}_{0}^{\infty}{\mathcal{V}}\(\frac{C{\mid}f{\mid}{\phi}}{{\gamma}}\){\psi}\).$$ Further, we discuss the above two inequalities for the conjugate of the modified integral Hardy operators. It will extend the existing results for the Hardy operator and its integral version.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.85.4-85
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• 1998