• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.07a
• /
• pp.119-122
• /
• 2001

ZnO thin films on (001) sapphire substrates have been deposited by pulsed laser deposition(PLD) technique at the oxygen pressure of 350 mTorr. In order to investigate the effect of post-annealing treatment with oxygenn pressure of 350 mTorr on the optical property of ZnO thin films, films have been annealed at various substrate temperatures after deposition. After post-annealing treatment in the oxygen ambient, the optical properties of the ZnO thin films were characterized by PL(Photoluminescence) and structural properties of the ZnO were characterized by XRD, and have investigated structural property and optical property for application of light emission device.

• Journal of the Korean Mathematical Society
• /
• v.31 no.3
• /
• pp.467-475
• /
• 1994

In 1983 Harmand and Lima [5] proved that if X is a Banach space for which K(X), the space of compact linear operators on X, is an M-ideal in L(X), the space of bounded linear operators on X, then it has the metric compact approximation property. A strong converse of the above result holds if X is a closed subspace of either $\elll_p(1 < p < \infty) or c_0 [2,15]$. In 1979 J. Johnson [7] actually proved that if X is a Banach space with the metric compact approximation property, then the annihilator K(X)^\bot$ of K(X) in $L(X)^*$ is the kernel of a norm-one projection in $L(X)^*$, which is the case if K(X) is an M-ideal in L(X).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.1
• /
• pp.167-171
• /
• 1999

The production of emulsion sausage generally contain nitrite as a curing agent for preservative effect and color as well as flavor development. This investigation describe a study on the inhibitory effect of chitosan against some spoilage bacteria and substitution effect of nitrite in sausages. Among of the chitosan, M.W. 120KDa of chitosan has shown an antimicrobial effect. When 0.2% of chitosan and half of normal nitrite content were added to sausage, effect of preservative quality was same that added to normal content of nitrite in sausages. Sausage added to 0.5% of chitosan has been a good storage property even though without nitrite. The growth of most of bacteria was inhibited 80% or more at 0.01~0.2% of chitosan. These results indicated that M.W. 120KDa of chitosan as a natural material could provide sausage protection and very reduced or substituted amount of nitrite against spoilage bacteria.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 1998.11a
• /
• pp.9-11
• /
• 1998

A phenomenon of electroluminescent radiate as electric field applied in the phosphor, in this paper, we produced the Powder Electroluminescent Device(PELD) which was changing the structure and the thickness of phosphor and insulator for realization of the PELD with high brightness. We made PELD with structure that is WK-1(ITO film/Phosphor/Insulator/Electrode), WK-2(ITO film/Phosphor/Insulator/Electro de), WK-3(ITO film/Phosphor/Insulator/Electrode), WK-4(ITO film/Phosphor+Insulator/ Electrode). The property of the produced PELD are analyzed by measuring the spectrum which electrical and optical property, the brightness and the transferred charge density. In this result, the structure of WK-4 have good luminescence property than others, it's effective thickness is 60${\mu}{\textrm}{m}$. At 100V 400Hz, High brightness of 2700cd/m2 was performed.

• Proceedings of the KIEE Conference
• /
• 1993.07b
• /
• pp.1239-1241
• /
• 1993

This paper studies on the improvement of non-tracking property which is very important matter for developing polymer insulator. Non-Tracking property of silicon rubber used for polymer insulator was investigated by ASTM D 2303 according to Aluminium Hydrate filler. Furthermore other electrical and mechanical properties were estimated. The optimum amount of Aluminium Hydrate should be considered by following test results.

• Journal of the Korean Society for Heat Treatment
• /
• v.21 no.4
• /
• pp.205-212
• /
• 2008

Characteristics of microstructures, mechanical properties and formability of two Al-20Si-5Fe-2Ni alloys produced by gas atomizing (P/M) and spray forming (S/F) respectively were compared at temperatures up to $560^{\circ}C$. Room temperature hardness values and tensile strengths of both alloys were increased in accordance with temperature after heat treatment above $300^{\circ}C$. The highest values of hardness and tensile strength of both alloys were obtained at $490^{\circ}C$. It was interpreted that increase in hardness and tensile strength according to heating temperature between $300{\sim}490^{\circ}C$ was mainly related to increase in internal stress between Al matrix and reprecipitated particles. S/F alloys showed better formability and wear property than P/M alloys due to the homogenity of microstructures above $300^{\circ}C$.

• Communications of the Korean Mathematical Society
• /
• v.39 no.2
• /
• pp.363-372
• /
• 2024

In this paper, we introduce a weak version of coherent that we call regular coherent property. A ring is called regular coherent, if every finitely generated regular ideal is finitely presented. We investigate the stability of this property under localization and homomorphic image, and its transfer to various contexts of constructions such as trivial ring extensions, pullbacks and amalgamated. Our results generate examples which enrich the current literature with new and original families of rings that satisfy this property.

• Proceedings of the KSME Conference
• /
• 2005.11a
• /
• pp.21.2-21.2
• /
• 2005

• Communications of the Korean Mathematical Society
• /
• v.12 no.4
• /
• pp.911-920
• /
• 1997

This note centers around the class M(A) of multipliers on a Gelfand algebra A. This class is a large subalgebra of the Banach algebra L(A). The aim of this note is to investigate some aspects concerning their local spectral properties of multipliers. In the last part of work we consider some applications to automatic continuity theory.

• Korean Journal of Mathematics
• /
• v.23 no.3
• /
• pp.447-456
• /
• 2015

In this paper we show that some operators defined on the Banach space with an unconditional basis and $L^1({\mu})$ into a Banach space with the RNP have liftable operators.