• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.917-919
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• 2003

The effect of conducting carbon layer on the performance of AC thin film EL display was examined. It was found that incorporation of small amount of carbon nano-tube and conducting additive greatly improve the luminance of the inorganic EL compared to the one with only conducting carbon black.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.727-735
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• 2002

Proton coupled carbon-13 relaxation experiment was performed to investigate the effect of vicinal protons on spin-lattice relaxation of methylene carbon-13 in n-undecane. A BIRD type pulse sequence was employed as a way to check the validity of describing the 13CH2 moiety as an isolated AX2 spin system. The results show that the presence of vicinal protons exerts substantial influence on the relaxation of methylene carbon-13, indicating that it is not a very good approximation to treat a methylene moiety as an isolated AX2 spin system.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.291-294
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• 2005

Presented are the results of recent tests on diagonal shear failure of reinforced concrete beams which are externally reinforced in the transverse direction by a unidirectional carbon fiber reinforced polymer, instead of the traditional steel stirrups. Three different series of the beams with different shear reinforcements, i.e. U-wrapping with carbon sheet, U-wrapping with carbon strips and full wrapping with carbon strips were tested. Those beams were geometrically similar, and the size range is 1:1.9:4. The failure of the beams are characterized by delamination, crushing of concrete and distributed shear cracks. It is found that the size effect is much weaker than that of the reference beams without CFRP. Therefore CFRP sheet may be used as the transverse reinforcement with a minor size effect. However, it is not clear that the same conclusion can be drawn in other sizes. Further researches are recommended.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.103-106
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• 2000

The electronic properties of carbon nanotube are currently the focus of considerable interest. In this paper, the electronic properties of finite length effect in carbon nanotube for cabon nanoscale device is presented. To calculate the electronic properties of carbon nanotube, Empirical potential method (Brenner' hydrocarbon potential) for carbon and Tight binding molecular dynamic (TBMD) simulation are used. As a result of study, we have known that the value of the band gap decreases with increasing the length of the tube. The energy band gap of (6, 6) armchair carbon nanotube have the ranges between 0.3 eV and 2.5 eV. Also, our results were compared with the results of the other computational techniques. As that result, our results are very well united.

• 천문학회지
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• 제47권4호
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• pp.123-135
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• 2014

A silicate carbon star is a carbon star which shows circumstellar silicate dust features. We collect a sample of 44 silicate carbon stars from the literature and investigate the validity of the classification. For some objects, it is uncertain whether the central star is a carbon star. We confirm that 29 objects are verified silicate carbon stars. We classify the confirmed objects into three subclasses based on the evolution phase of the central star. To investigate the effect of the chemical transition phase from O to C, we use the radiative transfer models for the detached silicate dust shells. The spectral energy distributions and the infrared two-color diagrams of the silicate carbon stars are compared with the theoretical model results. For the chemical transition model without considering the effect of a disk, we find that the life time of the silicate feature is about 50 to 400 years depending on the initial dust optical depth.

• 한국수소및신에너지학회논문집
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• 제28권2호
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• pp.206-211
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• 2017

Carbon felt electrode for the vanadium redox-flow battery (VRFB) has been studied to see the effect of grephene oxide (GO) treatment on the surface of the carbon felt electrode. In this paper, surface of carbon felt electrodes were treated with various concentrations of grephene oxide. Electrochemical analysis, cyclic voltammetry (CV), was performed to investigate redox characteristics as electrode for VRFB. Also the effect of GO on the introduction of functional group on the surface of carbon felt electrodes were investigated using X-ray photoelectron spectroscopy (XPS), which discovered increase in the overall functional group content on the surface of carbon felts.

• 한국대기환경학회지
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• 제34권3호
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• pp.486-492
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• 2018

Black carbon concentrations were measured along the altitude at various locations using a drone coupled with a small black carbon detector. The measurement locations are Eunseok Mountain, downtown, four places in KOREATECH campus, Byeongcheon, Cheonan, Chungcheongnam-do, and Chungbu Expressway in Ochang-eup, Cheongju, Chungcheongbuk-do. The average concentration of black carbon measured in Eunseok Mountain was $1.64{\mu}g/m^3$ and the average concentration near the Chungbu Expressway was measured to be $3.86{\mu}g/m^3$. The average concentrations of four places inside campus ranged from 1.37 to $2.67{\mu}g/m^3$. The concentration of black carbon at all places tended to be slightly decreased according to the altitude, but the influence of pollution source, geometry, wind speed, and wind direction are thought to be larger than the effect of altitude. Effect of air flow caused by drone flight on the measurement of black carbon were investigated and it resulted in that the measurement of BC concentration was affected by less than 5%.

• 한국재료학회지
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• 제13권7호
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• pp.415-419
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• 2003

Carbon nanotubes were formed on silicon substrate using microwave plasma-enhanced chemical vapor deposition method. The possibility of carbon nanotubes formation was related to the thickness of nickel catalyst. The growth behavior of carbon nanotubes under the identical thickness of nickel catalyst was strongly dependent on the magnitude of the applied bias voltage. High negative bias voltage (-400 V) gave the vertically well-aligned carbon nanotubes. The vertically well-aligned carbon nanotubes have the multi-walled structure with nickel catalyst at the end position of the nanotubes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1432-1435
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• 1998

Influences of carbon black contents on the tracking resistance, tan $\delta$ and dielectric constant volume resistivity and dielectric strength of EPDM compounds before and after a exposure to UV radiation were investigated. Carbon black content up to 1.5 phr have a positive effect to improve the resistance to tracking and erosion, since carbon black diminish the leakage current. Results from the study reveal that both tan $\delta$ and dielectric constant volume resistivity and dielectric strength are unaffected by adding of carbon black up to 2.0 phr and carbon black have a significant effect to suppress the photo-degradation of EPDM compounds.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.163-164
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• 2012

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. The substrate with oxygen incorporation and the substrate without oxygen incorporation were employed to elucidate the effect of substrate on the formation of carbon coils. The characteristics (formation densities, morphologies, and geometries) of the deposited carbon coils on the substrate were investigated. In case of Si substrate, the microsized carbon coils were dominant on the substrate surface. While, in case of oxygen incorporated substrate, the nanosized carbon coils were prevail on the substrate surface. The cause for the different geometry formation of carbon coils according to the different substrates was discussed in association with the different thermal expansion coefficient values between the substrate with oxygen incorporation and the substrate without oxygen incorporation.