• The Plant Pathology Journal
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• v.24 no.1
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• pp.97-100
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• 2008

Leaf blight symptoms and abnormal defoliation were found on Stachys riederi var. japonica, a medicinal plant, grown at Hongcheon, Gangwon province, Korea in 2007. A foliar nematode, Aphelenchoides fragariae was isolated from infected leaf tissues. The symptoms observed on host plant were leaf blotching, discoloration and browning of tissues, tan-colored interveinal necrotic lesions and large dead patches of necrotic tissues. This is the first report of A. fragariae occurring on S. riederi var. japonica.

• Journal of Microbiology and Biotechnology
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• v.3 no.4
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• pp.252-255
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• 1993

Pseudomonas maltophilia N246 carrying on OCT plasmid grew on n-alkanes of 6 to 14 carbon atoms, but not on n-alkanes of more carbon atoms. P. maltophilia strains with and without OCT plasmid could utilize primary alcohols. aldehydes and fatty acids derived from n-alkane. The N246 strain could also utilize monocarboxylic and dicarboxylic acids, and terminal branched dimethyloctane. Unlike the genes of alcohol dehydrogenase and aldehyde dehydrogenase which were located on both the chromosome and the OCT plasmid, genes for the alkane hydroxylase components were located only on the OCT plasmid in P. maltophilia N246.

• Journal of Microbiology
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• v.34 no.1
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• pp.38-39
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• 1996

The internal regions of nuclear small subunit rRNA from 6 plaeurotus species and 5 Pleurotus ostreatus strains were amplified by PCR and sequenced. The DNA sequences of 8 Pleurotus strains (P. ostreatus NFFA2, NFFA4501, NFFA4001, KFFA4001, KFCC11635, P florida, P. florida, P. sajor-cuju, P. pulmonarius, and P. spodoleucus) were idential, but P. cornucopiae differed from them in two bases out of 605 bases. However, p[hylogenetic analysis of the sequences by DNA-distance matrix and UPGMA methods showed that P. ostreatus NFFA2m1 and NFFA2m2, known as mutants of P. ostreatus NFFA2, belonged to anther group of Basidiomycotina, which is close to the genus Auricularia. The difference of the SSU rDNA sequences of P. cornucopiae from other Pleurotus species tested corresponds to the difference of mitochondrial plasmid type present in Pleurotus species as observed by Kim et al. (1993, Korean J. Microbiol. 31, 141-147).

• Fibers and Polymers
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• v.3 no.3
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• pp.103-108
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• 2002

The viscosity effect of matrix polymer on melt exfoliation behavior of an organoclay in poly($\varepsilon$-caprolactone) (PCL) was investigated. The viscosity of matrix polymer was controlled by changing the molecular weight of poly($\varepsilon$-eaprolactone), the processing temperature, and the rotor speed of a mini-molder. Applied shear stress facilitates the diffusion of polymer chains into the gallery of silicate layers by breaking silicate agglomerates down into smaller primary particles. When the viscosity of PCL is lower, silicate agglomerates are not perfectly broken into smaller primary particles. At higher viscosity, all of silicate agglomerates are broken down into primary particles, and finally into smaller nano-scale building blocks. It was also found that the degree of exfoliation of silicate layers is dependent upon not only the viscosity of matrix but thermodynamic variables.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.141-142
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• 2000

In order to improve electron field emission and its stability, tip surface of amorphous silicon field emitters have been coated with molybdenum layer with a thickness of 25 nm through the gate opening and annealed rapidly in inert ambient. Compared with amorphous silicon field emitters, Mo silicidized amorphous silicon field emitters exhibited lower turn on voltage about 9 V, 3.8 times higher maximum current, 3.1 times lower fluctuation range and less change of the emission current depending on the vacuum level.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1550-1553
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• 2009

We studied the human visual performance with PDP and LCD to clarify the relationships between viewer preference and chromatic adaption. In this paper, optical performance of the display is measured mechanically based on standard. The human visual performance about the display color image quality trough optical process is represented numerically based on CIECAM02. By comparing these results with the result of the questionnaire, performance of the display can be evaluated in detail.

• Korean Architects
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• s.511
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• pp.66-69
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• 2011

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.64.1-64.1
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• 2018

SNe light curves have been used to understand the expansion history of the universe, and a lot of efforts have gone into understanding the overall shape of the radioactively powered light curve. However, we still have little direct observational evidence for the theorized SN progenitor systems. Recent studies suggest that the light curve of a supernova shortly after its explosion (< 1 day) contains valuable information about its progenitor system and can be used to set a limit on the progenitor size, R*. In order to catch the early light curve of SNe explosion and understand SNe progenitors, we are performing a ~8hr interval monitoring survey of nearby galaxies (d < 50 Mpc) with 1-m class telescopes around the world. Through this survey, we expect to catch the very early precursor emission as faint as R=21 mag (~0.1 Rsun for the progenitor). In this poster, we outline this project, and present a few scientific highlights, such as the early light curve of SN 2015F in NGC 2442.

• Atmosphere
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• v.25 no.1
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• pp.169-177
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• 2015

Vertical distribution of particle mass concentrations was estimated from 8-year elastic-backscatter lidar and sky radiometer data, and from ground-level PM10 concentrations measured in Seoul. Lidar ratio and mass extinction efficiency were determined from aerosol optical depth (AOD) and ground-level PM10 concentrations, which were used as constraints to estimate particle mass concentration. The mean lidar ratio (with standard deviation) and mass extinction efficiency for the entire 8-year study period were $60.44{\pm}23.17$ sr and $3.69{\pm}3.00m^2g^{-1}$, respectively. The lidar ratio did not vary significantly with the ${\AA}ngstr{\ddot{o}}m$ exponent (less than ${\pm}10%$); however, the mass extinction efficiency decreases to $1.82{\pm}1.67m^2g^{-1}$ (51% less than the mean value) when the ${\AA}ngstr{\ddot{o}}m$ exponent is less than 0.5. This result implies that the particle mass concentration from lidar measurements can be underestimated for dust events. Seasonal variation of the particle mass concentration estimated from lidar measurements for the boundary layer, was quite different from ground-level PM10 measurements. This can be attributable to an inhomogeneous vertical distribution of aerosol in the boundary layer.

• Journal of Korean Elementary Science Education
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• v.31 no.2
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• pp.177-187
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• 2012

The purpose of this study was to acquire a better of how creativity center is perceived among students, teachers and parents by administering a questionnaire. A total of 320 people participated in this survey. We developed the questionnaire which as categorized by four specific areas: 1) people's overall perceptions of creativity education; 2) the way of using the creativity center 3) programing of creativity center 4) space composition of the creativity center. The summary of survey results included; firstly, people had paid attention to creativity education and creativity education; secondly, they want to make use of creativity center with informal learning and extra-curriculum; thirdly, they prefer to participate in many experience activities such as camp or experiments; lastly, they more need creativity experience program and utilization of DIY education. In conclusion, students, teachers and parents recognized creativity center is needed. Therefore, more intensive research and follow-up study on building creativity center should be highly considered.