• E2M - 전기 전자와 첨단 소재
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• 제10권10호
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• pp.1034-1040
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• 1997

A solar cell conversion effiency was degraded by grain boundary effect in polycrystalline silicon. Grain boundaries acted as potential barriers as well as recombination centers for the photo-generated carriers. To reduce these effects of the grain boundaries we investigated various influencing factors such as emitter thickness thermal treatment preferential chemical etching of grain boundaries grid design contact metal and top metallization along boundaries. Pretreatment in $N_2$atmosphere and gettering by POCl$_3$and Al were performed to obtain multicrystalline silicon of the reduced defect density. Structural electrical and optical properties of slar cells were characterized before and after each fabrication process. Improved conversion efficiencies of solar cell were obtained by a combination of pretreatment above 90$0^{\circ}C$ emitter layer of 0.43${\mu}{\textrm}{m}$ Al diffusion in to grain boundaries on rear side fine grid finger top Yb metal and buried contact metallization along grain boundaries.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.879-884
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• 1995

The results of performance assessment analyses have shown that the long-lived radionuclides such as I-129 control the potential individual dose impact to the public. I-129 is difficult-to-measure(DTM) in low-level waste because it is non-gamma emitting radionuclides and exists at extremely low concentrations in radioactive waste generated by nuclear reactors. In this study, computer modeling technique to predict release rate of I-129 is developed to provide another tools far performance assessment of land disposal facilities and characteristics of radwaste. Model suggested in this study will give conservative values of I-129 release rate far determination of radwaste characteristics. More detailed approach is implemented to account for release conditions of fuel source-nuclides. 1-131 concentration measured from reactor coolant and released fraction from tramp fuel have dominant roles in calculating release rate of I-129 with fuel defect conditions.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.474-474
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• 2011

Graphene is considered as a potential candidate for the key material in the ideal 2D nanoelectronics. Recently, it is reported that graphene has an interesting sensitivity to molecular adsorption on it. Such properties are believed to be enhanced by the existence of disorders and ripples inside graphene as well as by the interaction with the substrate underneath. Here, we report the effect of introducing structural disorders to the graphene on its electrical properties such as conductance, transconductance, low frequency noise, which can be successfully described by a simple model of the continuum percolation. In addition, the response of the graphene device to gaseous molecular adsorption was systematically investigated and the results were discussed along with the change in Raman spectra.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.631-635
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• 2000

Recently, the epoxy molded type PT for indoor and applied 25.8kV was often distroyed by degradation of insulation that effected many electric stress and defect of manufactured goods. therefore In this work, We can present a method of solution in the process of produce the PT through analysis of experiments. In order to reduce the PD (Partial Discharge) which was occurred at the insulation material of epoxy resin, we has many tried to remove faults In the process of the products,

• 한국진공학회지
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• 제4권S2호
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• pp.139-147
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• 1995

The mechanism of the ionized cluster beam deposition has been studied using Molecular Dynamics Simulation. The Embedded Atom Method(EAM) potential were used in the simulation. The impact of a Au95-cluster on Au(100) substrate was studied for the impact energies 0.15-10eV/atom. The dependency of the impact energy of cluster beam was observed. For the cluster energy impact of 10eV per atom, the defects on surface were created and the cluster embedded into substrate as an amorphous state. For the energy of 0.5eV per atom, the defect free homoepitaxial growth was observed and atomic scale nucleation was formated, which are in good agreement with experiment. Thus molecular dynamics simulation is very useful to study the mechanism of the ionized cluster beam deposition.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.43-45
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• 2008

According to industrial development, Ingots are more large and various. In particular large STS ingot. The probability of shrinkage cavity occurrence is higher than carbon steel and alloy steel. To manufacture ultra clean steel the technical development is nearly necessary for example controlling inclusions and total [H]. In this study, after measured the mold temperature and adjusted thermo conductivity of STS steel and compared existing mold to new one with CAE. As a result, the new mold more reduced than existing mold for the probability of shrinkage cavity occurrence.

• 대한한방내과학회지
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• 제22권3호
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• pp.437-442
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• 2001

For ischemic cerebrovascular disease, it is well known that early luxury perfusion is related to a good clinical outcome and single photon emission computed tomography(SPECT) has the potential for providing useful information about regional cerebral blood flow. We report one case of Rt. MCA infarction mainly treated by oriental medicine and revealed luxury perfusion without thrombolysis. In acute stage, neurological deficits of the patient were very severe. 99mTc-HMPAO SPECT images obtained 10days after the attack showed large perfusion defect in the Rt. MCA territory. We followed up 99mTc-HMPAO SPECT 40days after the ictus. Despite of the poor early perfusion, we found considerably improved perfusion and neurological improvement.

• 대한기계학회논문집
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• 제18권1호
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• pp.77-84
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• 1994

The oil crises in 1973 and 1978 stimulated the alternative fuel research activities in many countries around the world. Among the alternative fuels, methanol is one of the highest potential fuels for transportation. Methanol has been considered for use as automotive fuel, but it has a defect of the great latent vaporization heat. Therefore, authors have made the fuel vaporizing device in order to eliminate the fuel film flow heating the mixture. This paper presents a study on the characteristics of vaporization, engine performance, and emission which result from using the fuel vaporizing device.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2005년도 학술발표대회 논문집
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• pp.51-67
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• 2005

General chip SMD parts(chip resistance, chip capacitor, chip varistor etc.) are very wide sed electronics parts for IT units. But, failure modes are indistinct for these chip parts. In factory and field the failure modes are recognized to accidental failure mope caused by potential defect. In this paper used chip varistor ALT(Accelerate Life Test) test for verify general failure modes in chip SMD parts. Also the results are useful for general chip SMD ALT tests.

• 한국전기전자재료학회논문지
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• 제32권3호
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• pp.192-195
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• 2019

Single-crystal diamond obtained by chemical vapor deposition (CVD) exhibits great potential for use in next-generation power devices. Low defect density is required for the use of such power devices in high-power operations; however, plastic deformation and lattice strain increase the dislocation density during diamond growth by CVD. Therefore, characterization of the dislocations in CVD diamond is essential to ensure the growth of high-quality diamond. In this work, we analyze the characteristics of the dislocations in CVD diamond through synchrotron white beam X-ray topography. In estimate, many threading edge dislocations and five mixed dislocations were identified over the whole surface.