• Bulletin of the Korean Mathematical Society
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• v.48 no.6
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• pp.1169-1182
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• 2011

In this paper we study the existence of non-trivial weak solutions of the Neumann problem for quasilinear elliptic equations in the form $$-div(h(x){\mid}{\nabla}u{\mid}^{p-2}{\nabla}u)+b(x){\mid}u{\mid}^{p-2}u=f(x,\;u),\;p{\geq}2$$ in an unbounded domain ${\Omega}{\subset}\mathbb{R}^N$, $N{\geq}3$, with sufficiently smooth bounded boundary ${\partial}{\Omega}$, where $h(x){\in}L_{loc}^1(\overline{\Omega})$, $\overline{\Omega}={\Omega}{\cup}{\partial}{\Omega}$, $h(x){\geq}1$ for all $x{\in}{\Omega}$. The proof of main results rely essentially on the arguments of variational method.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.73.2-73.2
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• 2010

암흑에너지는 우주상수만으로 여러 우주론 관측 자료들을 잘 설명하고 있지만, 최근 SN Ia 자료가 축적됨에 따라 암흑에너지의 상태방정식 파라미터 $\omega$가 우주상수에서와 같이 -1인 상수인지, 시간에 따라 변하는지를 알아내기 위한 연구가 진행되고 있다. 본 연구에서는 $\omega$가 시간에 따라 갑자기 변하는(sudden jump) transition-$\omega$CDM 모형을 이용하여 SN Ia 자료를 Markov Chain Monte Carlo(MCMC) 방법을 통해 분석했다. Transition-$\omega$CDM 모형에서는 상수인 $\omega$의 값이 임의의 적색이동에서 변한다고 가정하였다. 분석에 사용된 SN Ia 데이터는 307개의 Union 자료와 90개의 CfA3 SN Ia가 추가된 Constitution 자료이며 개별적으로 분석됐다. 그 결과 transition 시기 전후 $\omega$ 값들의 확률밀도분포를 얻어내었고, 이를 통해 SN Ia의 특성을 조사하였다.

• Bulletin of the Korean Mathematical Society
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• v.54 no.3
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• pp.993-1002
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• 2017

Let ${\Omega}$ be a bounded, uniformly totally pseudoconvex domain in ${\mathbb{C}}^2$ with the smooth boundary b${\Omega}$. Assuming that ${\Omega}$ satisfies the negative ${\bar{\partial}}$ property. Let M be a positive, finite area divisor of ${\Omega}$. In this paper, we will prove that: if ${\Omega}$ admits a maximal type F and the ${\check{C}}eck$ cohomology class of the second order vanishes in ${\Omega}$, there is a bounded holomorphic function in ${\Omega}$ such that its zero set is M. The proof is based on the method given by Shaw [27].

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.123-123
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• 2015

Al doped ZnO(AZO) films as a transparent conductive oxide (TCO) electrode were deposited on glass, polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) at room temperature by a conventional rf-magneton sputtering (CMS) and a facing target sputtering (FTS) using Al2O3 and ZnO targets. In order to investigation of AZO properties, the structural, surface morphology, electrical, and optical characteristics of AZO films were respectively analyzed. The resistivities of AZO films using FTS system were $6.50{\times}10-4{\Omega}{\cdot}cm$ on glass, $7.0{\times}10-4{\Omega}{\cdot}cm$ on PEN, and $7.4{\times}10-4{\Omega}{\cdot}cm$ on PET substrates, while the values of AZO films using CMS system were $7.6{\times}10-4{\Omega}{\cdot}cm$ on glass, $1.20{\times}10-3{\Omega}{\cdot}cm$ on PEN, and $1.58{\times}10-3{\Omega}{\cdot}cm$ on PET substrates. The AZO-films deposited by FTS system showed uniform surface compared to those of the films by CMS system. We thought that the films deposited by FTS system had low stress due to bombardment of high energetic particles during CMS process, resulted in enhanced electrical conductivity and crystalline quality by highly c-axis preferred orientation and closely packed nano-crystalline of AZO films using FTS system.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.265-270
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• 1995

Transposon mutation of Xanthomonas campestris pv. vesicatoria (Xcv) was induced by using transposon omegon ($\Omega$)-Km (Tn $\Omega$Km), which was confirmed by resistance to kanamycin (KMr), and nonpathogenic mutants were selected through the inoculation test on pepper plants. The mutagenesis frequency was about 6$\times$10-8, and 53 out of 2,000 Kmr bacterial colonies tested were nonpathogenic to the pepper cultivar Cheung-Hong. Optimum conditions for the Tn $\Omega$Km mutagenesis of Xcv were Luria Bertani (LB) broth medium for culture of Xcv, yeast extract-dextrose-CaCO3 (YDC) agar medium for selection of Tn $\Omega$Km-mediated mutants, and over 1 to 2 in the ratio of the donor (Escherichia coli S17-1 with the plasmid pJFF350 $\Omega$Km) and the recipient (Xcv) in the culture for the mutagenesis. One of the 4 nonpathogenic mutants (WNP1, WNP3, WNP4 and WNP5), which had been reconfirmed through the inoculation on pepper cv. Dabokgun, showed no differences in the production of exoenzymes such as protease and polygalacturonase and extracellular polysaccharides in vitro and the bacterial growth rate from those of the wild type of Xcv.

• Nutritional Sciences
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• v.1 no.1
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• pp.42-50
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• 1998

In this study, we evaluated the dietary fatty-acid pattern and serum fatty-acid composition of middle school students (total, 355 ; male, 182 ; female, 173), who are vulnerable to excessive and unbalanced food intakes such as fatty acids and energy. In serum lipid levels, total Chol (p<0.05) and HDL-Chol (p<0.001) levels of female students were significantly higher than those of mal, students. The average fat intake was 23-26 energy % which falls in with the current recommendation level (15-25%) for adults. Although the average P/M/S ratio of dietary fat was 1.1/1.2/1.0 which approaches the recommended ratio, the average range of $\omega$6/$\omega$3 fatty acid ratio of dietary fat was found to be 12.0-16.5, which is higher than the presently recommended range of 4 -10. Some of the very high values found in this study were partly explained by the fact that the range of individual variation of $\omega$6/$\omega$3 ratios was very large. Mean daily intake of Chol was 357-361 mg. The n3 fatty acid intake of middle school students was higher in the LFHM (high fish low meat) group than in the LFHM (low fish high meat) group. EPA and DHA intakes appeared to be significantly higher (p<0.01) in the HFLM group than in the LFHM group as expected. Dietary total $\omega$3 fatty acids (p<0.05) and EPA (p<0.01) were also negatively associated with serum AA($\omega$6) levels. Interestingly, energy intakes and dietary SEAs such as 12 : 0 (p<0.05), 14 : 0 (p<0.01) and 16 : 0 (p<0.05) were negatively associated with serum AA ($\omega$6) levels. To lower the $\omega$6/$\omega$3 ratio of dietary fatty acids for children, frequent consumption of $\omega$3 series fatty-acid rich foods such as soy bean, bean products and fish is recommended. Detailed guidelines should be developed in recommending balanced food intake and qualitative fat intake for Korean adolescents taking heterogeneous groups into consideration. In accurately evaluating fatty acid intake, it is also necessary to have the fatty acid composition data of all foods consumed in each country.

• Nutritional Sciences
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• v.5 no.2
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• pp.68-74
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• 2002

Studies of the relationship between the composition of serum fatty acids and blood pressure are complex and controversial. Fatty acids, important constituents of biological membranes, could potentially affect vasoreactivities including blood pressure. In this study the compositions of fatty acids in serum phospholipids were compared between three types of hypertensive subjects (men, pre-menopausal women, and post-menopausal women) and their respective nrmotensive controls. Serum lipids were extracted and phospholipids were separated by thin layer chromatography. The percentage of palmitic acid (16 : 0) in serum phospholipids was significantly higher and the percentage of stearic acid (18 : 0) was significantly lower in all three hypertensive groups, compared with their corresponding control groups. Only in the group of post-menopausal women, palmitic acid was closely associated wish increases in both systolic (SBP) and diastolic blood pressure (DBP), while stearic acid was associated with decreases in both SBP and DBP. The polyunsaturated fatty acids in serum phospholipids behaved differently from saturated fatty acids. The ratios of products / precursor fatty acids, such as $\sumLCPUFA\omega6/18 : 2\omega$6, 20 : 4$\omega$6/18 : 2$\omega$6, ∑LCPUFA$\omega$3/18 : 3$\omega$3 and 22 : 6$\omega$3/20 : 5$\omega$3, were all clearly associated with both SBP and DBP in hypertensive, post-menopausal women. Desaturation and elongation in fatty acid metabolism could affect the bioavailability of eicosanoid precursors. Changes in the constituent fatty acids of phospholipids and eicosanoid precursors may also influence fluidity, ionic transport, hormone receptors and enzyme activities in biological membranes. In conclusion, both systolic and diastolic blood pressure in post-menopausal women was positively associated with the level of palmitic acid, and negatively associated with the level of stearic acid, in serum phospholipids. The relationships between serum phospholipid-$\omega$6 and $\omega$3 series fatty acids and blood pressure in women, especially in post-menopausal women, require further investigation by taking into consideration hormonal status and eicosanoid metabolism. Funker study is needed to determine the value of dietary manipulation of fatty acid constituents of serum phospholipids, relating to hypertension in women.

• Journal of Applied Biological Chemistry
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• v.44 no.1
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• pp.6-11
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• 2001

An ${\omega}-3$ fatty acid desaturase gene which is involved in de novo synthesis of -Iinolenate was isolated from cDNA library of Perilla frutescens. A cDNA library was constructed with mRNA extracted from perilla seeds of 12 DAF. The cDNA clone consisting of 1317-bp open reading frame encoding 438 amino acids with a relative MW of 50kDa, was isolated and showed 65-83% similarities to other known genes. This cDNA is deduced to encode a plastidal ${\omega}-3$ fatty acid desaturase based on the fact that it has higher homology to plastidal ones than to microsomal ones and its N-terminal sequence shares several characteristics of transit peptides of chloroplast proteins. Southern blot analysis of genomic DNA indicated that more than one gene or alleles for ${\omega}-3$ fatty acid desaturase are present in the genome of perilla. Northern blot analysis showed that the ${\omega}-3$ fatty acid desaturase gene is mainly revealed in early developing seeds and has different expression patterns depending on tissue types compared to the microsomal ones.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.135-144
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• 2015

The Korean daily intake of vegetable oils has increased about 2.5-fold from 17 g/day to 46 g/day for the last several decades. Perilla (Perilla frutescens var. frutescens) has been cultivated in Korea for a long time as a dietary oil seed which has the highest content of ${\alpha}$-linolenic acid, accounting for nearly 60%. It is known that the main role of ALA is as a precursor to the longer-chain ${\omega}-3$, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), the metabolic products of ${\alpha}$-linolenic acid (ALA, ${\omega}-3$). Dietary ${\omega}-3$ fatty acids reduce inflammation and the risk of chronic diseases such as heart disease, cancer, and arthritis, but they also may act as functional components for cognitive and behavioral function. Thus, ${\alpha}$-linolenic acid is one of the essential nutrients in modern dietary patterns in which much linoleic acid is consumed. Nevertheless, perilla oil, rich in ${\alpha}$-linolenic acid, can be easily oxidized, giving rise to controversies with respect to shelf life, the deterioration of the product's commercial value, and further related toxicity. Recent research using genetic modifications has tried to develop new plant oil seeds that balance the ratio of ${\omega}-6/{\omega}-3$ fatty acids. Such trials could be a strategy for improving an easily oxidizable property of perilla oil due to high ${\alpha}$-linolenic acid. Alternatively, appropriate application of antioxidant to the oil can be considerable.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.151-159
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• 1998

Elelctrical properties of $BaTiO_3$ were characterized with addition of $Y_2O_3, CaO,SiO_2$ and Mn to develope the composition of PTC thermistor suitable as a current limiting device for automobile motor system. With the addition of 0.2 mol% $Y_{2}O_3$ to $BaTiO_3$, the minimum resistance of 16.5 ${\Omega}{\cdot}$cm was obtained at room temperature. $(Ba_{0.996}Y_{0.004})TiO_3$ exibited a minimum resistance of 50${\Omega}{\cdot}$cm with addition of 1.6 mol% $SiO_2$. The grain size of $(Ba_{0.996}Y_{0.004})TiO_3$ decreased from 34.95 ${\mu}$m to 13.4 ${\mu}$m and thus breakdown voltage could be improved by changing the composition as $(Ba_{0.996}Y_{0.004}Ca_{0.05}) TiO_3$ with substition of 5 mol% Ca into Basites. When 0.04 mol% Mn was added, the optimum PTCR properties could be obtained : the resistivity at room temperature and ${\rho}_{max}/{\rho}_{min}$ were 30~40${\Omega}{\cdot}$cm and $1.5{\times}10^5$ respectively.