• Carbon letters
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• v.13 no.2
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• pp.99-108
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• 2012

The sol-gel technique has been studied to fabricate a homogeneous Fe-Mo/MgO catalyst. Ambient effects (air, Ar, and $H_2$) on thermal decomposition of the citrate precursor have been systematically investigated to fabricate an Fe-Mo/MgO catalyst. Severe agglomeration of metal catalyst was observed under thermal decomposition of citrate precursor in air atmosphere. Ar/$H_2$ atmosphere effectively restricted agglomeration of bimetallic catalyst and formation of highly-dispersed Fe-Mo/MgO catalyst with high specific surface-area due to the formation of Fe-Mo nanoclusters within MgO support. High-quality thin-multiwalled carbon nanotubes (t-MWCNTs) with uniform diameters were achieved on a large scale by catalytic decomposition of methane over Fe-Mo/MgO catalyst prepared under Ar-atmosphere. The produced t-MWCNTs had outer diameters in the range of 4-8 nm (average diameter ~6.6 nm) and wall numbers in the range of 4-7 graphenes. The as-synthesized t-MWCNTs showed product yields over 450% relative to the utilized Fe-Mo/MgO catalyst, and indicated a purity of about 85%.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.93-99
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• 1997

High Temperature wear behavior of plasma sprayed ZrO$_2$ and MoS$_2$, $Fe_2O_3$ coatings were investigated for high temperature wear resistance applications. The MoS$_2$, $Fe_2O_3$ added powders containing 2.5, 5.0, 7.5, 10.0 mol% of $MoS_2$, $Fe_2O_3$ for plasma spray were made by spray drying method. Wear test were performed at temperature ranges from room temperature to 600$\circ$C. The microstructural change of coatings and the worn. surface were examined by SEM and XRD. In ZrO$_2$ coating, the coefficient of friction and wear amount of room temperature to 400$\circ$C was increased with temperature and decreased with temperature over 400$\circ$C. The coefficient of friction and wear amount of MoS$_2$ added coatings were increased with temperature, but those of $Fe_2O_3$ added coatings had lower coefficient of friction and higher wear resistance than ZrO$_2$ coating.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.118-122
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• 1996

1wt% Pt/MoO$_3$ gas sensors for detecting H$_2$ gas were fabricated by the pressed pellet method and surface structures of Pt/MoO$_2$ were investigated by TEM and XRD. It was observed that as the calcination temperature is increased, the overlayers of MoO$_3$ on Pt are produced, but the Cl content in PtCl$\_$x/ are decreased. H$_2$ gas sensing properties in N$_2$ ambient and in air ambient were investigated, respectively, and Pt/MoO$_3$ had high sensitivity at low working temp ; 7.8% at 50$^{\circ}C$, 97.7% at 100$^{\circ}C$, 97.1% at 150$^{\circ}C$ when the specimens are treated at 400$^{\circ}C$, and 99.6% at 150$^{\circ}C$ when they are treated at 200$^{\circ}C$. It shows the development of a low-power type sensor is possible by using Pt/MoO$_3$.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1997.10a
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• pp.97-99
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• 1997

• Journal of Astronomy and Space Sciences
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• v.4 no.2
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• pp.95-99
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• 1987

The possibility of the cross-field diffusion of a fluid to generate magnetic fields on a large scale is examined. Application to the sunspot is discussed.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.6 no.1
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• pp.99-109
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• 1998

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.05a
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• pp.149-150
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• 2011

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.05a
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• pp.223-224
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• 2017

• Korean Journal of Materials Research
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• v.16 no.5
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• pp.297-301
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• 2006

Si/Mo multilayer anode consisting of active/inactive material was prepared using rf/dc magnetron sputtering. Molybdenum acts as a buffer against the volume change of the Silicon. Multilayer deposited on RT (reversible treatment) copper foil current collector to enhance adhesion between Silicon and copper foil. Deposited Silicon was identified as an amorphous. Amorphous has a relatively open structure than crystal structure, thus prevents the lattice expansion and has many diffusion paths of Li ion. When deposited time of Silicon and Molybdenum is 30 second and 2 second respectably, electrode has more capacity and good cycle stability. A 3000 nm thick multilayer was maintained 99% of the initial capacity (1624 $mAhg^{-1}$) after 100 cycles. As the increase of the multilayer thickness (4500 nm, 6000 nm), Si/Mo mutilayer anodes show aggravation cycle stability.

• Annual Conference on Human and Language Technology
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• 2007.10a
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• pp.99-106
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• 2007

본 연구는 국어의 모든 언어적 특성을 기술하고 이를 실제 형태소 분석에 적용할 수 있도록 다차원 해석 사전을 이용하는 형태소 분석 시스템인 moHANA(Morphological Hangul Analyzer)에 관한 연구이다. moHANA의 해석 사전은 태그정보 사전, 어휘 사전 그리고 문법 사전으로 구성된다. 태그정보 사전은 기존 형태소 해석기의 일차원적인 품사 정보와 달리 어류 태그정보, 형태적 정보, 통사적 정보, 의미적 정보 및 화용 정보의 5 차원 벡터 정보로 작성된다. 어휘 사전은 어휘와 그 어휘가 가질 수 있는 태그정보를 우선 순위에 기반하여 순서열로 가지며, 문법 사전은 특수 문법 연산자를 이용하여 태그정보 사전에 정의된 각각의 태그가 연결 가능한지 여부를 규정하는 문법이 구축되어 있다. 형태소가 가지는 태그정보를 다차원으로 정의하고 이에 따른 문법 규칙의 표현을 통해 보다 자세한 형태소 분석 및 새로운 형태소 태그의 삽입과 삭제의 용이함을 얻을 수 있다.