• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.106.4-106
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• 1998

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.153-154
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• 2011

• 대한화학회지
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• 제31권4호
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• pp.322-327
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• 1987

$ZrO_2$의 표면을 $H_2SO_4$로 처리하거나 $SO_2,\;H_2S,\;CS_2$로 처리한 후 산화시킴으로 개질하였다. 처리된 황화합물의 산화종과 산화상태를 적외선분광법과 X-선광전자분광법으로 조사하였다. 처리된 황화합물을 산화시킨 후에는 사용된 황화합물의 종류에는 관계없이 개질된 $ZrO_2$는 모두 강한 산성질을 나타내었다. 개질된 $ZrO_2$가 초강산의 성질을 나타내는 것은 가장 높은 산화상태의 황($SO_4{^{2-}}$)에 기인하였다.

• 한국재료학회지
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• 제16권5호
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• pp.318-322
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• 2006

Short-term high temperature degradation test was conducted on Hastelloy X, a candidate tube material for high temperature gas-cooled reactors (HTGR), to evaluate the variation of microstructure and mechanical property in air at $1050^{\circ}C$ during 2000 h. The dominant oxide layer was Cr-oxide and a very shallow Cr-depleted region was observed below the oxide layer. At the beginning of degradation, the island shape $M_6C$ precipitate (M=Mo-rich, Fe, Ni, Cr) was observed in matrix region. After 2000 h degradation, precipitate shape was changed to the chain shape and increased amount of precipitate. These results influenced mechanical property of the specimen which exposed in high temperature. Yield strength was decreased from 115MPa to 89 MPa after 24 h and 2000 h exposure, respectively.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.374-374
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• 2007

• 대한수학회지
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• 제56권6호
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• pp.1561-1597
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• 2019

In this paper we introduce the notions of topological entropy and topological pressure for non-autonomous iterated function systems (or NAIFSs for short) on countably infinite alphabets. NAIFSs differ from the usual (autonomous) iterated function systems, they are given [32] by a sequence of collections of continuous maps on a compact topological space, where maps are allowed to vary between iterations. Several basic properties of topological pressure and topological entropy of NAIFSs are provided. Especially, we generalize the classical Bowen's result to NAIFSs ensures that the topological entropy is concentrated on the set of nonwandering points. Then, we define the notion of specification property, under which, the NAIFSs have positive topological entropy and all points are entropy points. In particular, each NAIFS with the specification property is topologically chaotic. Additionally, the ${\ast}$-expansive property for NAIFSs is introduced. We will prove that the topological pressure of any continuous potential can be computed as a limit at a definite size scale whenever the NAIFS satisfies the ${\ast}$-expansive property. Finally, we study the NAIFSs induced by expanding maps. We prove that these NAIFSs having the specification and ${\ast}$-expansive properties.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권1호
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• pp.1-5
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• 2005

The vector magnetic property is defined as the relationship between the magnetic field strength vector H and the magnetic flux density vector B. It is very important for the development of high efficiency and the high-density electric machines. The electrical steel sheet for the machine core shows the remarkable vector behavior by the high magnetic flux density level. In this paper, the magnetic characteristic analysis using E&S2 model is introduced as the useful technology for the design and development.

• Journal of applied mathematics & informatics
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• 제19권1_2호
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• pp.385-395
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• 2005

A finite element scheme is considered for the viscous Cahn-Hilliard equation with the nonconstant gradient energy coefficient. The scheme inherits energy decay property and mass conservation as for the classical solution. We obtain the corresponding error estimate using the extended Lax-Richtmyer equivalence theorem.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.424-427
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• 1995

This paper proposes an analysis of an inverter circuit which has an induction heating load. Two major kinds of the inverters are E-class quasi resonant and half-bridge type. The analyses of induction heating load property and operation property are introduced. A simulation program which implements those properties is also introduced. The results of the simulation program are verified through experimental results.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.46-51
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• 2008

In this study, evaluation system of the thermal properties of the exothermic agents was investigated. Exothermic agents property evaluation system was developed by metering variation of power supply. Thermal properties of exothermic agents was affected by material mixture condition of exothermic agents, however, it was not affected by temperature. It is possible to make various exothermic agents by means of regulating thermal properties which is based on property evaluation system of exothermic agents.