• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.311-312
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• 2005

By using 45$^{\circ}$ obliqued evaporation method with electron beam system, uniformly vertical liquid crystal (LC) alignment was achieved. And a high pretilt angles of about 2.5$^{\circ}$ were measured. Also, it was verified that there are no variations of pretilt angle as a function of $SiO_x$ thin film thickness 20nm and 50nm. A good LC alignment states were observed at annealing temperature of 250$^{\circ}C$. The high pretilt angle and the good thermal stability of LC alignment by 45$^{\circ}$ obliqued electron beam evaporation method on the $SiO_x$ thin film can be achieved.

• 한국전기전자재료학회논문지
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• 제18권11호
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• pp.1024-1027
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• 2005

By using $45^{\circ}$ obliqued evaporation method with electron beam system, uniformly vertical liquid crystal (LC) alignment was achieved. And a high pretilt angles of about $2.5^{\circ}$ were measured. Also, it was verified that there are no variations of pretilt angle as a function of $SiO_x$ thin film thickness 20 nm and 50 nm. A good LC alignment states were observed at annealing temperature of $250^{\circ}C$. Consequently, the high pretilt angle and the good thermal stability of LC alignment by $45^{\circ}$ obliqued electron beam evaporation method on the $SiO_x$ thin film can be achieved.

• 대한기계학회논문집B
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• 제36권2호
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• pp.111-115
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• 2012

본 연구에서는 에틸렌 글리콜 기반의 ZnO 나노유체의 열전도도를 비정상열선법(Transient Hot Wire Method)를 이용하여 $10^{\circ}C$에서 $50^{\circ}C$까지 측정하였다. 에틸렌 글리콜 기반의 ZnO 나노유체는 전기선 폭발법을 사용하여 부피비 1%, 3%, 5.5%로 제작 되었으며, 투과전자현미경(Transmission Electron Microscope, TEM)을 이용하여 제작된 에틸렌 글리콜 기반의 ZnO 나노유체의 분산·부유 특성을 확인하였다. 열전도도 측정 결과 에틸렌 글리콜 기반의 ZnO 나노유체는 부피비에 따라 향상하였으며, 5.5%의 부피비에서 최대 26.5%의 열전도도 향상을 보였다. 측정 결과는 기존의 열전도도 예측 모델인 Maxwell 및 Hasselman & Johnson model 과 비교하였다.

• 한국수소및신에너지학회논문집
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• 제16권3호
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• pp.284-289
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• 2005

Thermal analysis of cryogenic-capable vessels with insulations have been carried out to store liquid hydrogen($LH_2$). The combined insulations of MLI(Multi-Layer Insulation) and VCS(Vapor-Cooled Shield) under high vacuum are considered in the analysis for various volumes of vessels. Vapor-Cooled Shields(VCS) are installed at cylinder wall as well as disc side of the $LH_2$ vessels. The results indicate that optimal distribution of boiloff vapor from $LH_2$ vessel into two sides of VCS exists based on the evaporation loss. As the volume of $LH_2$ vessel is increased, mass flow rate of boiloff is increased while the evaporation loss per unit volume is decreased.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.7-13
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• 1999

An experimental study was performed to discover the effect of silver coating on the frictional behavior of SM45C steel at sliding surfaces. Pure silver was coated the SM45C disk surfaces by a thermal evaporation method. Experiments using a pin-on-disk test-rig was performed under dry air and various humidity conditions. Friction coefficients increased to a high and unstable value after failure of coating, and friction coefficients increased with increasing the thickness of silver coated layer. But optimum coating thickness was not observed.

• Applied Science and Convergence Technology
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• 제24권5호
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• pp.142-150
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• 2015

A failure analysis of tungsten filaments used in quadrupole mass spectrometer for plasma process monitoring was carried by using SEM and EDS. Failed at high temperature, filaments showed two kinds of failure modes. The one is that diameter of filament became thinner gradually and finally snapped. The other is that filament abruptly snapped almost at a right angle. The EDS analysis showed Fe and C, including W and Fe, on the surface of failed filament. when failed filaments were treated with plasma in mixture of Ar and $CF_4$, the amount of Fe and C decreased. The failure analysis of filament showed that the cause of filament failure is thermal evaporation and grain growth of tungsten at high temperature.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.115-115
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• 2003

Silica nanostructures have been attached considerable attention because of theirs potential application in mesoscopic research and the potential use of large surface area structure of catalysts. SiO2 nannowire and nanorods was synthesized various methods including thermal evaporation, chemical vapor deposition (CVD), and laser ablation methods. In this experiments, SiO2 nanowire were grown using thermal evaporation method followed by VS (Vapor-Solid) growth mechanisms. Grown SiO2 nanowires were amorphous phases because of its low growth temperatures. Grown nanowires diameters were about 20-40nm at all growth conditions, but its microstructres were different by that used substrate because of it's oxygen contents.

• Tribology and Lubricants
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• 제14권3호
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• pp.1-6
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• 1998

An experimental study was performed to discover the effect of environmental conditions on the rolling resistance behavior of pure silver and lead coated 52100 bearing steel. Pure silver and lead coatings were produced by a thermal evaporation coating method. Experiments using a thrust ball bearing-typed rolling test-rig were performed under vacuum, dry air and controlled humidity conditions. Results showed that agglomeration of particles were suppressed in vacuum environment and resulted in low and stable rolling resistance by shakedown phenomena. Also, humidity related closely to the agglomeration of particles and the rolling resistance after the failure of coated layer.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.85-89
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• 2008

This study carried out field observations of measuring thermal environment, especially evaluating amount of water evaporation at roof Pond by field observations during the summer. Thermal environment measuring was categorized as air temperature, water temperature of roof pond, surface temperature, globe temperature, short and long wave radiation, net radiation, and amount of water evaporation by water level measurement. Results from this study could be used as fundamental for reducing heat Island phenomena.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.47-54
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• 1998

An experimental study was performed to discover the effect of environmental conditions on the rolling resistance behavior of pure silver and lead coated 52100 bearing steel. Pure silver and lead coating were produced by a thermal evaporation coating method. Experiments using a thrust ball bearing-typed rolling test-rig were performed under vacuum, dry air and controlled humidity conditions. Results showed that agglomeration of particles were prevented in vacuum environment and as it showed low and stable rolling resistance by shakedown phenomena. Also, humidity relates closely to the agglomeration of particles and increased the rolling resistance after the failure of coated layer.