• 한국표면공학회지
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• 제51권1호
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• pp.11-20
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• 2018

Hydrophobic and Superhydrophobic surfaces are promising technology for the surface finishing of metallic materials due to its water-repellency. Realization of highly water-repellent surface on aluminum and its alloys provides various functionalities for real application fields. In order to realize the hydrophobic/superhydrophobic surfaces on aluminum and its alloys, various technologies have been demonstrated. Especially, traditional anodic oxidation for aluminum has been widely employed for the morphological texturing of surfaces, which is essential to enhance the hydrophobic efficiency. De-wetting superhydrophobic surface on aluminum provides various exceptional properties, such as anti-corrosion, anti-/de-icing, anti-biofouling, drag reduction, self-cleaning and liquid separation. Nevertheless, the durability and stability of superhydrophobic surfaces still remain challenges for their actual applications in engineering systems and industry. In this review, the theoretical/experimental studies and current technical limitations on the hydrophobic and superhydrophobic surface using anodic oxidation of aluminum have been summarized.

• 한국자동차공학회논문집
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• 제7권8호
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• pp.123-131
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• 1999

Natural gas is one of the most promising alternative fuels for automotive vehicles. However, natural gas varies in compositional between the originating fields and may be further modified due to processing and additional mixing. These variations are known to affect engine performance and emissions through changes in fuel metering and combustion characteristics. In the present study, the effect of gas compositions on vehicle performance such as fuel economy, driveability and exhaust emissions was examined. Analysis are made of using 3 types of NGVs which were made by automakers and 6 different fuels which are selected in consideration of the variation in fuel composition on the worldwide market. The results may be utilized to develop natural gas natural gas engine in automaekrs and/or to establish the fuel standard in the refueling stations.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.67.2-67.2
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• 2012

Graphene is expected to have a significant impact in various fields in the foreseeable future. For example, graphene is considered to be a promising candidate to replace indium tin oxide (ITO) as transparent conductive electrodes in optoelectronics applications. We report the tunability of the wavelength of localized surface plasmon resonance by varying the distance between graphene and Au nanoparticles [1]. It is estimated that every nanometer of change in the distance between graphene and the nanoparticles corresponds to a resonance wavelength shift of ~12 nm. The nanoparticle-graphene separation changes the coupling strength of the electromagnetic field of the excited plasmons in the nanoparticles and the antiparallel image dipoles in graphene. We also show a hysteresis in the conductance and capacitance can serve as a platform for graphene memory devices. We report the hysteresis in capacitance-voltage measurements on top gated bilayer graphene which provide a direct experimental evidence of the existence of charge traps as the cause for the hysteresis [2]. By applying a back gate bias to tune the Fermi level, an opposite sequence of switching with the different charge carriers, holes and electrons, is found [3]. The charging and discharging effect is proposed to explain this ambipolar bistable hysteretic switching.

• Macromolecular Research
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• 제17권6호
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• pp.403-410
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• 2009

Cytotoxicity is a severe problem of cadmium sulfide nanoparticles(CSNPs) for use in biological systems. In the present study, mercaptoacetic acid-coated CSNPs were conjugated with bovine serum albumin (BSA) to improve biocompatibility. The surface properties of the CSNPs and albumin-conjugated CSNPs (ACSNPs) were characterized by XRD, UV, FTIR, EA, TEM and DLS. Human breast cancer cells (KB cells) were then cultured in the presence of the nanoparticles to evaluate the cytotoxicity of CSNPs and ACSNPs. Finally, the fluorescence intensity of the nanoparticles' aqueous solution was examined using a fluorescence spectrometer. The results showed that the cell compatibility and fluorescence intensity of ACSNPs were higher than those of CSNPs. The strongly luminescent features of the biocompatible ACSNPs are promising for use in biological fields such as cellular labeling, intracellular tracking and molecular imaging.

• 한국분말재료학회지
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• 제25권4호
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• pp.346-354
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• 2018

Over the last decade, the study of the synthesis of semiconductor colloidal quantum dots has progressed at a tremendous rate. Colloidal quantum dots, which possess unique spectral-luminescent characteristics, are of great interest in the development of novel materials and devices, which are promising for use in various fields. Several studies have been carried out on hot injection synthesis methods. However, these methods have been found to be unsuitable for large-capacity synthesis. Therefore, this review paper introduces synthesis methods other than the hot injection synthesis method, to synthesize quantum dots with excellent optical properties, through continuous synthesis and large capacity synthesis. In addition, examples of the application of synthesized colloid quantum dots in displays, solar cells, and bio industries are provided.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.96-102
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• 1998

A lot of individual ginseng plants were selected in the farmer's fields to develop new ginseng varieties with desirable traits. Among them, a promising line has been developed through comparative cultivation of several lines selected with pure line separation of local raced. It was then designated as "KC (denotes Korean Ginseng)" and tested in the regional yield and adaptation trials for 10 years. KG lines grew vigorously after 4 years of age. Especially, KG 102 line arson운 them showed traits of multiple and short stems. As for the root characters, the length of taproot of KG 101 line was longer than that of local race, Jakyung-jong, or other lines ailed the root weight of KG 102 line waIn 15 % higher than that of local race. In general, KG 101, KG 103, KG 104, and Hwangsauk-jong had good root shape. Total amount of ginsenosides of ginseng taproot was the highest in KG 103 line than in local race and other lines. In these studies, we, elected three superior lines, KG 101, KG 102, and KG 103, having characteristic of good root shape, high yield, and large amount of ginsenoside, respectively.

• Asia Pacific Journal of Business Review
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• 제1권2호
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• pp.63-88
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• 2017

With the advent of new frontiers in robotics, the spectrum of robot research area has widened in many fields and applications. Other than conventional robot research, many technologies such as smart devices, drones, healthcare robots, and soft robots are emerging as promising applications. Due to the research complexity of this topic, this research requires international collaboration and should be fertilized by R&D policies. This paper aims to propose a method to perform a cross-national analysis of robot research with unstructured data such as papers in the proceedings of an international conference. Text analytics are applied to extract research issues and applications in an automatic manner.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.18-19
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• 2008

Polycrystalline(poly) 3C-SiC film is a promising structural material for M/NEMS used in harsh environments, bio and fields. In order to realize poly 3C-SiC based M/NEMS devices, the electrical properties of poly 3C-SiC film have to be optimized. The n-type poly 3C-SiC thin film is deposited by APCVD using HMDS$(Si_2(CH_3)_6)$ as single precursor and are in-situ doped using N2. Resistivity values as low as 0.014 $\Omega$cm were achieved. The carrier concentration increased with doping from $3.0819\times10^{17}$ to $2.2994\times10^{19}cm^{-3}$ and electronicmobility increased from 2.433 to 29.299 $cm^2/V{\cdot}s$.

• Journal of Ginseng Research
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• 제22권1호
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• pp.11-17
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• 1998

To develop a new ginseng varieties with good quality and high yielding, a lot of individual ginseng plants were selected in the farmer's fields in 1972. Among them, a promising line, 7259-3-1, has been developed through comparative cultivation of several lines selected with pure line separation of local races in Korea Ginseng '||'&'||' Tobacco Research Institute. Preliminary and advanced yield trials were performed for 8 years. It was then designated as "KG 101" and tested in the regional yield and adaptation trials for 10 years (1981-1990). KG101 has a green stem with light violet and orange-yellow fruit and flowers 3-7 days later than local race, Takyungjong. Taproot of KG101 was longer than local race Jakyungjong, and root yield of KG101 was 9% higher than local race Jakyungjong. In red ginseng quality, the rates of Chun-Jeesam (Chun and Jee means 1st and 2nd grade, respectively) were 22.3% and 9.4% for KG101 and Jakyungjong, respectively. In these results, it was clarified that KG101 was superior ginseng line with good quality.y.

• KEPCO Journal on Electric Power and Energy
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• 제1권1호
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• pp.73-77
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• 2015

Offshore wind farms extend a distance from an onshore grid to increase their generating power, but long distance and high power transmissions raise a lot of cost challenges. LFAC (Low Frequency AC) transmission is a new promising technology in high power and low cost power transmission fields against HVDC (High Voltage DC) and HVAC (High Voltage AC) transmissions. This paper presents an economic comparison of LFAC and HVDC transmissions for large offshore wind farms. The economic assessments of two different transmission technologies are analyzed and compared in terms of wind farm capacities (600 MW and 900 MW) and distances (from 25 km to 100 km) from the onshore grid. Based on this comparison, the economic feasibility of LFAC is verified as a most economical solution for remote offshore wind farms.