• Journal of Korean Electronics
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• v.26 no.4
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• pp.38-41
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• 2006

• Journal of Korean Electronics
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• v.26 no.1
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• pp.19-22
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• 2006

• Magazine of RCR
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• v.4 no.1
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• pp.26-31
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• 2009

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.2
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• pp.13-24
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• 2000

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.2
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• pp.25-40
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• 2000

• Journal of the Chungcheong Mathematical Society
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• v.26 no.2
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• pp.411-420
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• 2013

We consider fractional Gussian noise and FARIMA sequence with Gaussian innovations and show that the suitably scaled distributions of the FARIMA sequences converge to fractional Gaussian noise in the sense of finite dimensional distributions. Finally, we figure out ACF function and estimate the self-similarity parameter H of FARIMA(0, $d$, 0) by using R/S method.

• Nonlinear Functional Analysis and Applications
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• v.26 no.5
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• pp.1035-1044
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• 2021

Existence and uniqueness results for solutions of system of Riemann-Liouville (R-L) fractional differential equations with initial time difference are obtained. Monotone technique is developed to obtain existence and uniqueness of solutions of system of R-L fractional differential equations with initial time difference.

• Natural Product Sciences
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• v.26 no.2
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• pp.151-157
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• 2020

Extensive column chromatography separation of the MeOH extract from the aerial parts of Phyllanthus urinaria afforded seventeen compounds (1 - 17). The structures of the compounds were elucidated by physicochemical and spectroscopic methods to be 5'-β-D-glucopyranosyloxyjasmonic butyl ester (1), (+)-cucurbic acid (2), dendranthemoside B (3), boscialin 4'-O-β-D-glucoside (4), 4,5-dihydroblumenol A (5), (6R,9R)-megastigman-4-ene-9,13-diol (6), (3S,5R,6S,9R)-3,6-dihydroxy-5,6-dihydro-β-ionol (7), (6S,9R)-roseoside (8), mallophenol B (9), icariside B₅ (10), corchoinoside B (11), canangaionoside (12), 5,6-epoxy-3-hydroxy-7-megastigmen-9-one (13), icariside B₂ (14), (7E)-2β,3β-dihydroxy-megastigm-7-en-9-one (15), betulalbuside A (16), and loliolide (17). The compounds 1, and 3 - 16 were isolated for the first time from this plant. The absolute stereochemistry of compound 1 was newly determined. The isolated compounds were tested for cytotoxic activity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay, but all the compounds showed weak cytotoxic activities.

• Journal of Technology Innovation
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• v.27 no.3
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• pp.1-26
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• 2019

The Korean economy has undergone growth based on manufacturing end products. The Korean government aims to advance industry by strengthening the materials and components industry, which is attracting more attention in terms of maintaining the competitiveness of existing key industries, and fostering new industries required in the era of the Fourth Industrial Revolution. Despite this importance, there is insufficient related research on the efficient R&D of the materials and components industry. This study analyzed the R&D efficiency. In addition, exploratory research was conducted on the impact of corporate size and type of cooperation on R&D efficiency. Output variables were set to reflect economic performance and the empirical analysis revealed that overall R&D efficiency is low. Small firms were found to perform better than large firms in terms of firm-size, and the efficiency of business-university-research cooperation is worse than other types of cooperation. This study is exploratory research considering the materials and components industry, and the results provide implications for research institutions and regarding types of cooperation. This is expected to help develop polices for qualitative growth and R&D strategies for investment and allocation.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1728-1734
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• 2005

The interactions of Cu(II)-meso-Tetrakis(n-N-methylpyridiniumyl)porphyrin (n = 2,3,4), respectively referred to as o-, m- and p-CuTMPyP, and DNA, poly$[d(A-T)_2]$ and poly$[d(G-C)_2]$ were investigated by circular and linear dichroism (CD and LD). In the o-CuTMPyP case, in which the rotation of the pyridinium ring is prevented, the shape of the CD spectrum when associated to DNA and poly$[d(A-T)_2]$ resembles and is characterized by a positive band at a low drug to DNA concentration ratio (R ratio) and is bisignate at a high R ratio. The former CD spectrum shape has been attributed to porphyrin that is bound monomerically outside of DNA while the latter can be attributed to those that are stacked. When o-CuTMPyP is bound to poly$[d(G-C)_2]$, the excitonic CD appeared at a relatively high R ratio. In contrast, a characteristic negative CD band in the Soret region was apparent for both m- and p-CuTMPyP when bound to DNA and poly$[d(G-C)_2]$ at the low R ratios, indicating that the porphyrin molecule intercalates. However, the DNA is bent near the intercalation site and the plane of the porphyrin molecule tilts relative to the DNA helix axis, as judged by the magnitude of the reduced LD. Various stacking patterns were identified by the shape of the CD spectrum for m- and p-CuTMPyP when bound to poly$[d(A-T)_2]$. Three species for the former complex and two for the latter complex were found which may reflect the extent of the stacking.