• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.663-665
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• 2014

• Tribology and Lubricants
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• 제25권1호
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• pp.20-24
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• 2009

TiC-derived carbon coatings have been synthesized at $600^{\circ}C$ temperature treatment with $H_2/Cl_2$ mixture gases. From Raman spectroscopy measurements, the modified layer was covered with carbon and the thick-ness of the layer was increased with increasing reaction time. And $I_D/I_G$ ratio was decreased with increasing reaction time. The superior tribological property was obtained from TiC reacted with $Cl_2$ gas for 2 hrs. And the tribological property measurements indicate that TiC-derived carbon layer has $0.9{\times}10_{-6}mm^3/Nm$ in wear coefficient and 0.13 in friction coefficient.

• 한국세라믹학회지
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• 제43권10호
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• pp.660-665
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• 2006

The mechanical properties of $Al_2O_3$-SiC composites manufactured with adding various amount and size of SiC particles have been measured and analyzed. Generally, the elastic modulus of the composites shows about 50% less than that of PL-8 (45 wt% $Al_2O_3$-51 wt% $SiO_2$-4 wt% other oxides), but the flexural strength is similar with each other. The impact resistance property of $Al_2O_3$-SiC composite against high velocity copper jet was lower than that of PL-8 when SiC particles of approximately 3 $\mu$m diameter was added to. It is caused probably due to the micro-pores made by oxidation of SiC particles. However, in the case of the less-weighted $Al_2O_3$-SiC composite adding to 10 wt% SiC with average diameter of 10 $\mu$m and sintering at 1200$^{\circ}C$, the impact resistance property was improved up to 37 percent compared with that of PL-8.

• 한국재료학회지
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• 제8권12호
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• pp.1090-1098
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• 1998

Rf 마그네트론 반응성 스퍼터링법으로 $RuO_2$박막을 Si 및 Ru/Si 기판 위에 증착한 뒤 산소 분위기 (1atm)에서 열처리를 하여 RuO$_2$박막의 열적 안정성 및 확산방지 특성을 연구하였다.$ RuO_2$박막은 산소 분위기 $700^{\circ}C$에서 10분까지 안정하여, 산소와 실리콘에 대한 우수한 확산방지 특성을 나타내었다 $750^{\circ}C$ 열처리시, 우선 성장 방위에 관계없이 RuO$_2$박막 표면 및 내부에서 휘발 반응이 일어남과 동시에 확산방지 특성은 저하되었다. 그러나 80$0^{\circ}C$ 열처리 시에는 $750^{\circ}C$ 열처리와는 다른 미세구조를 나타내었다. 이러한 열처리 온도에 따른 휘발반응에는 RuO$_2$의 표면 결함구조인 $RuO_3$와 증착시 박막내 함유된 과잉산소에 의한 결함 구조가 영향을 주는 것으로 판단된다.

• 대한수학회논문집
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• 제33권2호
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• pp.371-378
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• 2018

This article concerns a ring property which is seated between IFP and IPFP rings. We study the insertion property of nonzero powers at zero products, introducing the concept of strongly IPFP ring. The structure of strongly IPFP rings is investigated in relation with nearly seated ring properties and ring extensions.

• 대한수학회지
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• 제51권4호
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• pp.837-851
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• 2014

We consider ${\omega}$-chaos as defined by S. H. Li in 1993. We show that c-dense ${\omega}$-scrambled sets are present in every transitive system with two-sided limit shadowing property (TSLmSP) and that every transitive map on topological graph has a dense Mycielski ${\omega}$-scrambled set. As a preliminary step, we provide a characterization of dynamical properties of maps with TSLmSP.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1761-1763
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• 1998

ITO(Iridium-Tin Oxide) thin film, as discharge electrodes in AC PDP, should have low resistivity and high transparency. Regarded as a high deposition rate method, the ITO thin film fabricated by the facing target sputtering system has been studied in this paper. The electrical property of the ITO film deposited below $150^{\circ}C$ is not satisfied. The SEM pictures show that the ITO films deposited below $150^{\circ}C$ are amorphous. After being annealed the amorphous ITO films become crystalline, and for this reason, the electrical property of amorphous ITO films can be effectively improved by annealing process. An ITO film with the resistivity as low as $1.99{\times}10^{-4}$ and transparency above 85% has be gotten after vacuum annealing at $300^{\circ}C$ for 2 hours while deposited at $75^{\circ}C$. The corresponding deposition rate is $220{\AA}/min$.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.361-366
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• 1999

The life of AC PDP depends largely on the sputtering-resistant property of the protecting layer such as MgO thin-film. However, it is very difficult to measure the sputtering-resistant property in the stable driving conditions of AC PDP. In this paper we have suggested a high speed measurement technique of the sputtering-resistant property of MgO thin-film by applying the MgO thin-film as the target of RF magnetron sputtering system. We have also applied this method to the e-beam MgO and sputter-MgO and e-beam MgO superior to sputter-MgO 3 times over. Also, the relation of Xe gas partial pressure(X) and sputtered thickness(Y) was Y=3.4X+13.5.

• Journal of Welding and Joining
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• 제33권5호
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• pp.31-34
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• 2015

Microstructure and tensile property in the weld heat-affected zone (HAZ) of austenitic Fe-Mn-Al-C low density steels were investigated through transmission electron microscopy analysis and tensile tests. The HAZ samples were prepared using Gleeble simulation with high heat input welding condition of 300 kJ/cm, and the HAZ peak temperature of $1200^{\circ}C$ was determined from differential scanning calorimetry (DSC) test. The strain- stress responses of base steels showed that the addition of V improved the tensile and yield strength by grain refinement and precipitation strengthening. Tensile strength and elongation decreased in the weld HAZ as compared to the base steel, due to grain growth, while V-added steel had a higher HAZ strength as compared than V-free steel.

• 열처리공학회지
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• 제21권1호
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• pp.26-32
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• 2008

Effects of annealing treatment on microstructure and mechanical property of co-sputtered TiNi thin films were studied. As-deposited films showed amorphous state. However, above annealing temperature of $500^{\circ}C$ martensite phase (B19'), precipitate phase ($Ti_2Ni$) and a small amount of parent phase ($B_2$) were present, and phase transformation behaviors were three multi-step phase transformations $B19^{\prime}{\rightarrow}B_2$ and $B_2{\rightarrow}R-phase$ and $R-phase{\rightarrow}B19^{\prime}$. Increase of martensite transformation temperature, increase of microhardness and Young's modulus of TiNi films annealed above $500^{\circ}C$ were discussed in terms of precipitate phase.