• East Asian mathematical journal
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• v.31 no.4
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• pp.445-458
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• 2015

In this paper, we provide a geometrical solving method about the equiangular problem appeared in the solving process of the isoperimetric problem of polygon. In fact we deal with the following problem in the view of the productive thinking centered on the circle: Let B and G be fixed points, and let $\bar{AB}=\bar{AP_1}=\bar{DP_1}=\bar{DP_2}=\bar{FP_2}=\bar{FP_3}=\bar{HP_{n-1}}=\bar{HG}$. Then find the position of moving points $P_i(1{\leq}i{\leq}n)$ to maximize the sum of areas of the triangles that lie on the line segment $\bar{BG}$.

• KSBB Journal
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• v.15 no.3
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• pp.318-322
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• 2000

An oxygen-sensitive fumarate reductase has been purified from the cytosol fraction of the Enterococcus faecalis RKY1 grown anaerobically on a defined medium containing glycerol and fumarate. A major portion of the purification was performed with employing Triton X-100 and reducing agents by Phenyl-sepharose CL-4B DEAE-sepharose and Dephadex G-150 The final activity was 0.42 unit/mg. The deduced molecular mass of active band was 66 kDa. The optimal pH and temperature for the activity were 7.0 and 38$^{\circ}C$ respectively. The enzyme activity was not affected by 1mM metal ions such as bacl2 $.$2H2O HgCl2 MnCl2$.$4H2O ZnCl2 CuCl2$.$2H2O Mgcl2$.$6H2O FeSo4$.$7H2O and by EDTA. Partially purified enzyme ws yellow in color ; spectroscopic study indicated the presence of flavins as a cofactor.

• Journal of Life Science
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• v.9 no.4
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• pp.414-422
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• 1999

Our works performed for preparation of oligosaccharides from carrageenan, seaweed polysaccharide, and one active strain for carrageenan was isolated from sea water and identified to Pseudomonas alcaligenes. Carrageenan degrading enzyme was purified from the culture fluid of isolated strain-Pseudomonas alcaligenes JCL-43, by DEAE-Cellulose, Sephadex G-100, Q-Sepharose and CM Sepharose CL-6B column chromatography. Two enzyme-F-I, F-II- was identified this purifying process, and the molecular weight of the purified carrageenase were estimated to be 23.6kDa and 30.2kDa, respectively. The optimum pH and temperature for two carrageenase activity were 7.0 and 4$0^{\circ}C$. These enzymes were stable in the pH range of 6.0~7.5 and lower than 5$0^{\circ}C$, and required 1.5% NaCl for optimum activity. And these carragennase were inhibited by metal ions such as Cu2+, Zn2+, Hg2+, but increased by Ba2+ and Ca2+, and showed specificity on -carrageenan.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.153-156
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• 2002

The characterization of a partially purified, cellulase-free, thermostable alkaline xylanase from thermoalkalophilic Bacillus sp. JB-99 was investigated. The xylanase production was the highest when birchwood xylan was added to a medium containing finely powdered rice bran, showing 4,826 IU$ml^-1$ of activity for 15 h of incubation. The partially purified xylanase exhibited an optimum temperature and pH at $70^C{\circ}$ and 10, respectively. The enzyme was stable at pH 5-11 at $50^C{\circ}$. The xylanase activity was strongly inhibited by $Hg^2+$, while dithiothreitol, cysteine, and ${\beta}$-mercaptoethanol enhanced the activity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.2
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• pp.50-57
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• 2004

Mercurous Bromide ($Hg_2Br_2$) crystals hold promise for many acousto-optic and opto-electronic applications. This material is prepared in closed ampoules by the physical vapor transport (PVT) growth method. We investigate the effects of solutal convection on the crystal growth rate in a horizontal configuration for diffusive-convection conditions and purely diffusion conditions achievable in a low gravity environment. Our results show that the growth rate is decreased by a factor of one-fourth with a ten reduction of gravitational acceleration near y = 2.0 cm. For 0.1 $g_O$ the growth rate pattern exhibits relatively flat which is intimately related to diffusion-dominated processes. The growth rate nonuniformity is regardless of aspect ratio across the interfacial positions from 0 to 1.5. Also, the effect of a factor of the ten reduction in the gravitational acceleration is same to both Ar = 5 and 2. The enlargement in the molecular weight of B from 50 to 500 by a factor 4 causes a decrease in the maximum growth rate by the same factor, indicative of the effect of solutal gradients.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.168-169
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• 2003

최근 세계적 주목을 받고 있는 spin FET 소자는 반도체에 주입된 spin 편향된 전자가 gate voltage(V$_{G}$)에 의해 반도체 계면에 유도된 전기장의 영향을 받아, Spin 세차운동을 하는 mechanism(Rashba 효과)이 근간을 이루고 있다. 작은 band gap을 가지는 반도체(narrow gap 반도체)는 작은 유효질량의 전자에 의해서 이러한 Rashba 효과를 크게 할 수 있어서, spin FET 구현을 위한 강력한 후보이며, 요즘 한창 연구되고 있는 주제이기도 하다. Rashba 효과가 저자기장 영역에서의 weak antilocalization효과로 나타남을 이용하여, 본 논문에서는 metal gate가 형성된 HgCdTe FET를 제작하여(FET1 시료, Fig. 1(a)참조), V$_{G}$에 따른 weak localization(WL) 및 weak antilocalization(WAL) 효과를 얻었다. 또한, Rashba 효과에 의한 spin 세차운동을 측정할 수 있는 소자(FET3 시료, Fig.1(b) 참조)를 제작하여 spin FET 구조에 대하여 연구하였다.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.346-350
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• 2005

In this study, to investigate the influence on the seam puckering by the mechanical properties of textiles, it was measured from 4 polyester/cotton samples. We reached the following conclusion in influences of the seam puckering by the thread, iron and laundry. Seam puckering is occurred several times by repeating the laundry. according to iron method, the seam puckering is stronger in order of T/C1> T/C2> T/C3> T/C4 by the samples and order of 40's/2> 60's/3> 50's/2> 60's/2 by the threads, the relation between sample's mechanical properties and seam strength and obtainment of formula. We can find that seam puckering is related with B, 2HB, G, 2HG5, RC, T among the mechanical properties and the estimated formulas which get from mechanical factors.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.3_4
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• pp.521-526
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• 2004

The fragrant fabrics are prepared by the attaching microcapsules using acrylic binder. To improve the handle of fragrant fabrics, pretreatment by softener is suggested. The durability of fragrant fabrics and the change of their handle are investigated. It is carried out One-way ANOVA and Duncan test to determine bending properties, shear properties, surface properties of untreated, SO-MC and BI-MC by Kawabata system. BI-MC shows significant differences in B and 2HB. SO-MC shows significant differences in G and 2HG. It turned out the pretreatment by softener mitigated the effect of binder and makes fabrics softer than untreated fabrics.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.1
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• pp.37-45
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• 2005

Adsorption equilibrium data of pure solvent vapors (n-Hexane, Toluene, MEK) as well as their binary mixtures on activated carbon (sorbonorit $B_4$) were experimentally determined in the range of 293.2~323.2 K and beyond saturated vapor pressure corresponding to experimental temperature. Langmuir, Freundlich, LRC, W-VSM, FH-VSM were estimated for the predication of single component as well as binary mixtuer systems. The isosteric heat of adsorption at infinite dilution of pure n-hexane, toluene, MEK on activated carbon were 45.18, 25.85, 34.62 Kcal/mol, respectively, also, n-hexane-toluene binary adsorption of activated carbon formed an azeotrope at 293.2 K and total pressure 5.1~10.3 mmHg.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.87-91
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• 1968

To research the characteristics of cellulose produced from one strains of Rhizopus(R-B 14) when it acts on the carboxyl methyl cellulose, this experiment was carried out in crude purified cellulose. The results obtained were as follows: 1. The optimum pH of cellulose was from 4. 5 to 5 .5 and the range of its stability to the pH was considerably extensive and it was from 4 to 7. 2. The optimum temperature of cellulose was $50^{\circ}C$ and the activity of it was instantly inactivated at $70^{\circ}C$. 3. The inhibition of the metal ions to the activity of cellulose was as follows; $Hg^{++}$ > $Ag^+$ +/ > $Fe^{+++}$ > $Pb^{++}$. But the activity of cellulose was not affected at all by $Na^+$, $K^+$ and $Mg^{++}$.