• Proceedings of the PSK Conference
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• 2002.04a
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• pp.195.3-196
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• 2002

• Journal of Powder Materials
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• v.18 no.3
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• pp.256-261
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• 2011

In order to make a $Cu_2ZnSnSe_4$ (CZTSe) sputtering target sintered for solar cell application, synthesis of CZTSe compound by solid state reaction of Cu, Zn, Sn and Se mixed powders and effects of ball milling condition on sinterability such as ball size, combination of ball size, ball milling time and sintering temperature, was investigated. As a result of this research, sintering at $500^{\circ}C$ after ball milling using mixed balls of 1 mm and 3 mm for 72 hours was the optimum condition to synthesis near stoichiometric composition of $Cu_2ZnSnSe_4$ and to prepare sintered pellet with high density relatively.

• Journal of the Korean Statistical Society
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• v.13 no.1
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• pp.42-47
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• 1984

In this paper, the means of the estimators for the coefficient of variation (CV) in an underlying Pareto distribution are expressed in terms of confluent hypergeometric functions. The numericla values of the biases for the CV estimators in the Pareto distribution are also obtained.

• Textile Coloration and Finishing
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• v.2 no.3
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• pp.8-13
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• 1990

In order to study the modification of wettability, tactility, and bathochromicity of the poly (ethylene Terephthalate) (PET) fabrics, low-temperature plasma$(O_2)$ has been irradiated on the PET fabrics in various conditions. The results obtained from this study were as follows; 1) The weight loss rate of plasma-treated PET fabrics is proportional to irradiation time and internal gas temperature of treating chamber. Also, the effect of weight loss is remarkable at gas pressure ranging from 3 torr to 5 torr. 2) The bathochromic effect of PET fabrics treated with low-temperature plasma$(O_2)$ was improved.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.114-120
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• 1988

We have studied the mechanism by examining the effect of ginseng on the epoxide hydrolase which is catabolized the reactive intermetabolite of bromobenzene, and bromobenzene-induced hepatotoxicity. It was observed that ginseng saponin fraction protects against bromobenzene-induced hepatotoxicity in mice as evidenced 1. increased the epoxide hydrolase activity, 2. lower serum transaminase activity, 3. decreased the formation of lipid peroxide. These results suggested that the inducing effect of ginseng on the epoxide hydrolase is believed to be a possible detoxication mechanism for the bromobenzene toxicity in mice.

• Textile Coloration and Finishing
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• v.2 no.3
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• pp.26-35
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• 1990

This study was carried out with the view of fundamental investigating to improve the tactile and the hygroscopicity of Poly(ethylene Terephthalate) (PET)fibers. Mono-sodium ethylene glycolate in ethylene glycol (MSEG-EG) solution was prepared and PET films were treated with it. The following conclusions were obtained. When PET films were decomposed in MSEG-EG solution, decomposition rate constant showed an exponential relationship with treating temperature; activition energy was 23.30 Kcal/mol, activation enthalpy was 22.52~22.60 Kcal/mol and activation entropy was -29.20~ -29.41 e.u. On the basis of the results obtained above and structure identification of decomposition products, it was found that the decomposition reaction proceeded through ester interchange reaction.

• Communications of the Korean Mathematical Society
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• v.10 no.1
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• pp.23-26
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• 1995

Throughout this paper R will always denote an integral domain with the quotient field K. Let A denote the polynomial ring R[x], I be an ideal of $A, I_K = I \otimes_R K$ and $J = I_K \cap A$.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.11a
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• pp.97-106
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• 1997

• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.135-145
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• 1995

A new algorithm was given to successively fit the multiexponential function/nonlinear function to data by a weighted least squares method, using Gauss-Newton, Marquardt, gradient and DUD methods for convergence. This study also considers the problem of linear-nonlimear weighted least squares estimation which is based upon the usual Taylor's formula process.

• Textile Coloration and Finishing
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• v.3 no.2
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• pp.25-33
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• 1991

Poly(ethylene terephthalate)(PET) and nylon 6 films stretched uniaxially and biaxially were sputter etched in the presence of argon gas. The surface of the etched films was investigated using a scanning electron microscope(SEM). While cracks perpendicular to the stretched direction were observed in the uniaxil stretched films sputter etched for 30 min., many protrusions were formed in the biaxial stretched films at the height of 0.3-0.4 gm for PET and $0.1-0.2\mum$ for nylon 6. The tops of two or three protrusions merged etching time increased to 60 min. The contact angle to water of the sputter etched PET and nylon 6 films decreased steeply when etched for one to 3 min. In order to investigate chemical changes on the surface ESCA analysis was carried out. In both films sputter etched $C_{1s}$ intensity decreased and $O_{1s}$ intensity increased compared with the unetched ones.