• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.422.1-422.1
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• 2016

Graphene quantum dots (GQDs), a new kind of carbon-based photo luminescent nanomaterial from chemically modified graphene oxide (CMGO) or chemically modified graphene (CMG), has attracted extensive research attention in the last few years due to its outstanding chemical, optical and electrical properties. To further extended its potential applications as optoelectronic devices, solar cells, bio and bio-sensors and so on, intensive research efforts have been devoted to the CMG. However, the CMG, a suspension of aqueous, have problematic since they are prone to agglomeration after drying a solvent. In this study, we synthesized the GQDs from graphite and deposited on silicon substrate by kinetic spray. The photo luminescent properties of deposited GQD films were analyzed and compared with initial GQDs suspension. In addition, its carbon properties were investigated with GQDs solution properties. The properties of deposited GQD films by kinetic spray were similar to that of the GQDs suspension in water. We could provide a pathway for silicon-based silicon based device applications. Finally, the well-adjusted GQD films with photo luminescence effects will show Energy-Down-Shift layer effects on silicon solar cells. The GQD layers deposited at nozzle scan speeds of 40, 30, 20, and 10 mm/s were evaluated after they were used to fabricate crystalline-silicon solar cells; the results indicate that GQDs play an important role in increasing the optical absorptivity of the cells. The short-circuit current density (Jsc) was enhanced by about 2.94 % (0.9 mA/cm2) at 30 mm/s. Compared to a reference device without a GQD energy-down-shift layer, the PCE of p-type silicon solar cells was improved by 2.7% (0.4 percentage points).

• Toxicological Research
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• v.33 no.1
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• pp.63-69
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• 2017

Transmembrane protein 39A (TMEM39A) belongs to the TMEM39 family. TMEM39A gene is a susceptibility locus for multiple sclerosis. In addition, TMEM39A seems to be implicated in systemic lupus erythematosus. However, any possible involvement of TMEM39A in cancer remains largely unknown. In the present report, we provide evidence that TMEM39A may play a role in brain tumors. Western blotting using an anti-TMEM39A antibody indicated that TMEM39A was overexpressed in glioblastoma cell lines, including U87-MG and U251-MG. Deep-sequencing transcriptomic profiling of U87-MG and U251-MG cells revealed that TMEM39A transcripts were upregulated in such cells compared with those of the cerebral cortex. Confocal microscopic analysis of U251-MG cells stained with anti-TMEM39A antibody showed that TMEM39A was located in dot-like structures lying close to the nucleus. TMEM39A probably located to mitochondria or to endosomes. Immunohistochemical analysis of glioma tissue specimens indicated that TMEM39A was markedly upregulated in such samples. Bioinformatic analysis of the Rembrandt knowledge base also supported upregulation of TMEM39A mRNA levels in glioma patients. Together, the results afford strong evidence that TMEM39A is upregulated in glioma cell lines and glioma tissue specimens. Therefore, TMEM39A may serve as a novel diagnostic marker of, and a therapeutic target for, gliomas and other cancers.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.329-336
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• 2016

In the outdoor advertising and industrial sites, are trying to implement the LED electric bulletin board system that is based on image processing in order to express a variety of intention in real time. Recently, in various field, rather than simple text representation, the importance of intuitive communication using images is increasing. Thus, instead of outputting the simple input information for communication, a system that can output a real-time information being sought. Therefore, the system is directed to overcoming by converting the problem of mapping an image on a variety of conventional LED display that can not be output images, the possible image output formats. Using an LED of low power, it has developed to output the efficient messages and images within a limited resources. This paper provides a system capable of managing the LED display on the wireless network. Atmega2560, Wi-Fi module, using the server and Android applications client, rather than printing a text only, it is a system to reduce the load generated image output character output in to the conversion process as can be managed by the server.

• Journal of the Korean Vacuum Society
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• v.15 no.2
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• pp.194-200
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• 2006

Self-assembled InAs/InAl(Ga)As quantum dots (QDs) were grown on InP substrates by a molecular-beam epiaxy, and their structural and optical properties were investigated by atomic force microscopy (AFM), transmission electron microscopy (TEM), and room-temperature photoluminescence (PL). AFM images indicated that the InAs quantum structures showed various shapes such as quantum dashes, asymmetric and symmetric QDs mainly caused by the initial surface conditions of InAl(Ga)As with the intrinsic phase separation. For the buried InAs QDs in an InAlGaAs matrix, the average lateral size and height of QDs were 23 and 2 nm, respectively. By changing the growth conditions for the QD samples, the emission wavelength of $1.55{\mu}m$ was obtained, which is one of the wavelength windows for fiber optic communications.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.3
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• pp.110-113
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• 2011

In this paper, we propose a new method for the fabrication of GaN microstructures formed only on the vertex of GaN pyramid by using of metal catalysts. GaN pyramidal structures were selectively grown on 3 ${\mu}m$ $SiO_2$ dot patterns followed by thin film deposition of Au and Cr only on the vertex area of the GaN pyramids with precisely controlled photolithography. After the metal deposition, the samples were loaded in the MOVPE reactor for the growth of GaN microstructures for 10 minutes. Temperature for the growth of the GaN microstructures was changed from $650^{\circ}C$ to $750^{\circ}C$. Rod type GaN microstructures were grown in the direction of vertical to the six {1-101} facets and the shape of the GaN microstructures was changed depend on the type of metal.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.7-10
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• 1999

This study was carried out with the purpose of looking into the transcriptionally regulated genes related to the anther development, characterizing them, and applying their promoters to induce male-sterile plants and restore their fertility. Fifteen anther-specific clones were isolated from the anther cDNA library of Chinese cabbage through the differential screening and sequenced partially at both ends. These partial sequence data showed that cDNA clones BAN52, 84, 101, and 229 are very similar to polygalacturonase, ascorbate oxidase, $H^+-translocating$ ATPase, and pectin esterase genes respectively. However, the other clones have not been matched to any of gene sequences in data bank. In northern dot blot analysis, the transcripts of cDNA clone BAN5, 10, 33, 52, 57, 102, 103, 215, 229 appeared in the flower bud of 2.1 mm in length and their amounts were gradually increased along with the anther development. Transcription of cDNA clone BAN32, 54, 62, 84, 101 began in flower bud of 3.9 mm, which is the late stage in anther development. However, the transcription of BAN87 was very small, but its transcript was detected in all anther developmental stages.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.39-46
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• 2010

In 2007, Iowa department of transportation (DOT) initiated to run the falling weight deflectometer (FWD) network-level testing along Iowa highway and road systems and to build a comprehensive database of deflection data and subsequent structural analysis, which are used for detecting pavement structure failure, estimating expected life, and calculating overlay requirements over a desired design life. Iowa's current FWD networklevel testing protocol requires that pavements are tested at three-drop level with 8-deflection basin collected at each drop level. The test point is determined by the length of the tested pavement section. However, the current FWD network-level program could cover about 20% of Iowa's highway and road systems annually. Therefore, the current FWD network-level test protocol should be simplified to test more than 20% of Iowa's highway and road systems for the network-level test annually. The main objective of this research is to investigate if the minimum number of drop levels and test points could be reduced to increase the testing production rate and reduce the cost of testing and traffic control without sacrificing the quality of the FWD data. Based upon the limited FWD network-level test data of eighty-three composite pavement sections, there was no significant difference between the mean values of three different response parameters when the number of drop levels and test points were reduced from the current FWD network-level testing protocol. As a result, the production rate of FWD tests would increase and the cost of testing and traffic control would be decreased without sacrificing the quality of the FWD data.

• Korean Journal of Materials Research
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• v.20 no.11
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• pp.586-591
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• 2010

Solar cells have been more intensely studied as part of the effort to find alternatives to fossil fuels as power sources. The progression of the first two generations of solar cells has seen a sacrifice of higher efficiency for more economic use of materials. The use of a single junction makes both these types of cells lose power in two major ways: by the non-absorption of incident light of energy below the band gap; and by the dissipation by heat loss of light energy in excess of the band gap. Therefore, multi junction solar cells have been proposed as a solution to this problem. However, the $1^{st}$ and $2^{nd}$ generation solar cells have efficiency limits because a photon makes just one electron-hole pair. Fabrication of all-silicon tandem cells using an Si quantum dot superlattice structure (QD SLS) is one possible suggestion. In this study, an $SiO_x$ matrix system was investigated and analyzed for potential use as an all-silicon multi-junction solar cell. Si quantum dots with a super lattice structure (Si QD SLS) were prepared by alternating deposition of Si rich oxide (SRO; $SiO_x$ (x = 0.8, 1.12)) and $SiO_2$ layers using RF magnetron co-sputtering and subsequent annealing at temperatures between 800 and $1,100^{\circ}C$ under nitrogen ambient. Annealing temperatures and times affected the formation of Si QDs in the SRO film. Fourier transform infrared spectroscopy (FTIR) spectra and x-ray photoelectron spectroscopy (XPS) revealed that nanocrystalline Si QDs started to precipitate after annealing at $1,100^{\circ}C$ for one hour. Transmission electron microscopy (TEM) images clearly showed SRO/$SiO_2$ SLS and Si QDs formation in each 4, 6, and 8 nm SRO layer after annealing at $1,100^{\circ}C$ for two hours. The systematic investigation of precipitation behavior of Si QDs in $SiO_2$ matrices is presented.

• The Journal of Internal Korean Medicine
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• v.29 no.2
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• pp.469-489
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• 2008

Objectives : The purpose of this study was to investigate the effects of Chungganhaeju-tang(Qingganjiejiu-tang) on alcoholic liver damaged by applying proteomics. Materials and Methods : Sprague-Dawley rats were used in this experiment the rats were divided into the normal group, the control group(alcohol) and the sample group(CGHJT +alcohol). The ethanol was orally administered twice a day for 6 weeks in the control and sample groups. Water instead of ethanol was orally administered twice a day for 6 weeks in the normal group. CGHJT extract was orally administered once a day for 6 weeks in the sample group. The livers of each group were processed and assessed by histology, Western Blot, $Oxyblot^{TM}$, CBB and 2-dimensional electrophoresis. Results : In the histological findings of the liver, CGHJT inhibited hepatic fibrogenesis induced by alcohol. TIMP-1 decreased in the sample group assessed by western blot and statistical significance was noted by dot blotting(p<0.05). In the $Oxyblot^{TM}$, protein oxidation induced by alcohol treatment decreased with CGHJT. In the 2-dimensional electrophoresis finding, increased proteins alcohol such as HSP 60, 60kDa heat shock protein, 3-mercaptopyruvate sulfurtransferase were normalized by CGHJT. CGHJT was considered to normalize the anti-oxidation activity elevated by alcohol. In the 2-dimensional electrophoresis finding, increased oxidized proteins such as actin, prolyl 4-hydroxylase beta polypeptide, 94kDa glucose regulated protein(GRP94), heat shock protein 90-alpha(HSC86), calreticulin precursor(CRP55), ATP synthase beta chain mitochondrial precursor, caspase-8 precursor, and dihydrolipoamide succinyltransferase(E2) decreased with CGHJT. CGHJT was considered to reduce the oxidative stress of alcohol. Conclusion : Chungganhaeju-tang(Qingganjiejiu-tang) exerts an inhibitory effect against the fibrosis and protein oxidation induced by alcohol treatment of rat liver. CGHJT was considered to normalize the elevated anti-oxidation activity by alcohol and to reduce the level of oxidative stress due to alcohol.

• Archives of design research
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• v.20 no.1 s.69
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• pp.287-296
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• 2007

Since the beginning of the 20th century, the art has developed its artistic qualities in exercising an influence on the creative elements of the fashion. In this sense, the fashion is one of many methods of which given time's arts, their compositions, and elements can be expressed, recognized, and experienced. In this study, artworks of Roy Lichtenstein, who took the leading, active role of pop artist have been studied. The purpose of this study is to present practical application of the art and aesthetic and artistic application of clothing by studying and applying the factors of Roy's paintings. The conclusion through actual designing is as follows: First, Lichtenstein interested with the characteristic of print media. He combined the image of commercial technique with the traditional painting by using Ben-day dots. Second, he reduces his form and color to the simplest possible elements. Third, by applying Lichtenstein's works to fashion design, we can make creative and aesthetic fashion works. Fourth, his Ben-day dots and stripe was applied to variant dots and stripe pattern in the fashion design. Roy Lichtenstein is expected to continually affect modern fashion and also fashion of the future. Furthermore Lichtenstein's works are expected to be further studied under various methods and ways, and those aesthetic characteristics would be developed and expressed more in fashion design under various perspectives.