• Journal of The Korean Astronomical Society
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• v.34 no.2
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• pp.67-80
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• 2001

Chemical evolution of galaxies can be understood by studying the spatial distribution of heavy elements. We selected two nearby galaxies, M31 and M33 and investigated spectrum of their HII regions: a) the elec-tron densities have been derived from the [S II] 6717/6731 ratio along with the most recent atomic constants (Hyung & Aller 1996); b) the electron temperatures were determinated from the Pagel's empirical method. Nebula Model (Hyung 1994) has been employed to predict the spectral line intensities which gives the proper chemical abundances. The model would predict the line intensities correctly only when various input parameters such as the effective central star temperatures, gravity log g, model atmosphere as well as the geometry and the nebula physical condition are appropriate. Thus, the determination of chemical abundances of O, S, N of the two nearby galaxies M31 and M33 has been done, which shows a radial dependance of O/H and N/H: decrease with the distance, or increasing electron temperature due to the elemental deficiency. Abundances of M31 appear to be enhanced than those of M33.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.45.2-45.2
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• 2013

We studied recent evolution of M31 and M33 with star-forming regions and hot massive stars. We use GALEX far-UV and near-UV imaging to detect the star-forming regions and trace the recent star formation across the entire disk of galaxies. The GALEX imaging, combining deep sensitivity and entire coverage of these galaxies, provides a complete picture of the recent star formation in M31 and M33, and its variation with environment throughout these galaxies. We also show results from recent extensive surveys in M31 and M33 with Hubble Space Telescope multi-wavelength data including UV filters, which imaged several regions at a linear resolution of less than half a pc in these galaxies. Both datasets allow us to study the hierarchical structure of star formation: the youngest stellar groups are the most compact, and are often arranged withing broader, sparser structures. The derived recent star-formation rates are rather similar for the two galaxies, when scaled for the respective areas.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.69.1-69.1
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• 2012

We present a comprehensive study of star-forming regions and young star clusters in M33. We use GALEX far-UV and near-UV imaging to detect these young stellar populations tracing recent star formation across the disk of M33. The GALEX imaging, combining deep sensitivity and entire coverage of the galaxy, provides a complete view of the recent star formation in M33 and its variation with environment throughout the galaxy. We discuss variation of various properties (e.g., age, mass, spatial distribution) of star-forming regions and young star clusters in M33 which allow to provide constraints of recent star formation history of this galaxy.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.1
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• pp.39-45
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• 1979

Egg masses of the root- knot nematodes ( Meloidogyne incognita, M. arenaria and M. haply) were exposed to two different regimes of soil moisture (459 and 2459) and temperature ( -2$^{\circ}C$ and 33$^{\circ}C$), quite extreme condition in their natural environment, and their survival rate was compared. Three species did not show any difference in the rate when exposed to either soil moisture for 25 days, with the rate in the range of 8.6% to 10.4%. In response to temperature treatment, however, they differed : the best survival rate was obtained from M. incognita at high temperature ( 33"C) and from M, hapla at low temperature (-2$^{\circ}C$) plot. The third species (M. arenaria) was intermediate in both temperature regimes.imes.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.88-93
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• 1989

To improve a new yeast strain capable of converting xylan to ethanol directly, we tried protoplast fusion between xylose fermenting yeast (Candida sp. X-6-41) and xylan assimilating yeast (Crypto-coccus sp. XB-33), finally selected the most promising two fusants (XFU-1 and XFU-2). As the optimum conditions for protoplast formation, the yeast cells were cultured to exponential phase in YPD and YPX containing 0.6M KCI, respectively, and then treated with zymolyase (0.25mg/$m\ell$), cellulase(4mg/$m\ell$) and 100mM 2-mercaptoethanol at pH 8 and 3$0^{\circ}C$. The protoplasts of parental auxotrophs were fused in the presence of 20mM CaCl$_2$and 40% polyethylene glycol(M.W.4000). The physiological and morphological characteristics of the fusants, such as assimilation of carbon sources, cell size, growth rate, xylanase activity and xylan fermentation ability were investigated. Xylanase activity of fusants that cultured in chemically minimal medium was higher than that of fusants that cultured in completed medium, because xylanase producing activity of xylose fermenting yeast(X-6-41) was inhibited by isoleucine.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.308-319
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• 2020

In this study, the field applicability of the recently constructed multifunctional fishway in Seomunbo, Yeongcheon-si, and Gyeongsangbuk-do were examined. The analysis variables were R/C slab (S1) and R/C+S/C slab (S2), the underground passage standard areas (width × length) were 1.4 m × 0.2 m, 1.4 m × 0.3 m, and 1.4 m × 0.6 m, and the flow velocities were 0.8, 1.2, and 1.6 m/s. As a result of the analysis, the safety of the design of Seomunbo was evaluated. The analysis showed compared to the Seomoon Weir fishway, the maximum stress of S2 decreased by 24 - 32%, the bending moment of the underground passage decreased by 16 - 33%, the maximum stress of the sidewall decreased by 20 - 36%. In addition, the bending moment of the upper slab decreased by 17 - 33%, the maximum stress of the upper slab decreased by 9 - 28%, and the bending moment decreased by 19 - 33%. Complementation was required in the following percentages: 18% and 14% for the maximum stress and bending moment of the underground passage, respectively, 15% and 17% for the maximum sidewall stress and bending moment, respectively, and 11% and 16% for the upper slab maximum stress and bending moment, respectively. The results showed that S2 was superior to that of the Seomoon Weir fishway, and the underground passage size of 1.4 m × 0.3 m was superior to those of 1.4 m × 0.2 m and 1.4 m × 0.6 m, and R/C+S/C slab was superior to that of R/C slab. The findings are expected to be useful for constructing and designing the multifunctional fishway.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.2
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• pp.105-111
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• 2024

This paper deals with the minimum linear arrangement(MinLA) of a lattice graph, to which an approximate algorithm of linear complexity O(n) remains as a viable solution, deriving the optimal MinLA of 31,680 for 33×33 lattice. This paper proposes a partitioning arrangement algorithm of complexity O(1) that delivers exact solution to the minimum linear arrangement. The proposed partitioning arrangement algorithm could be seen as loading boxes into a container. It firstly partitions m rows into r₁,r₂,r₃ and n columns into c₁,c₂,c₃, only to obtain 7 containers. Containers are partitioning with a rule. It finally assigns numbers to vertices in each of the partitioned boxes location-wise so as to obtain the MinLA. Given m,n≥11, the size of boxes C₂,C₄,C₆ is increased by 2 until an increase in the MinLA is detected. This process repeats itself 4 times at maximum given m,n≤100. When tested to lattice in the range of 2≤n≤100, the proposed algorithm has proved its universal applicability to lattices of both m=n and m≠n. It has also obtained optimal results for 33×33 and 100×100 lattices superior to those obtained by existing algorithms. The minimum linear arrangement algorithm proposed in this paper, with its simplicity and outstanding performance, could therefore be also applied to the field of Very Large Scale Integration circuit where m,n are infinitely large.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.149-158
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• 2013

The objective of this study was to investigate the antioxidative capacity of ethanol extracts from Sanguisorbae officinalis L. root (Sanguisorbae radix) in vitro. The concentration of Sanguisorbae radix extract at which DPPH radical scavenging activity was inhibited by 50% was 0.33 mg/mL, which was similar to $IC_{50}$ of ${\alpha}$-tocopherol (0.40 mg/mL), as compared to 100% by pyrogallol as a reference. Total antioxidant status was examined by total antioxidant capacity against ABTS radical reactions. Total antioxidant capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ${\alpha}$-tocopherol. Superoxide scavenging activities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of catechin. Oxygen radical absorbance capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ascorbic acid. Cupric reducing antioxidant capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ${\alpha}$-tocopherol. Sanguisorbae radix extract prevented supercoiled DNA strand breakage induced by hydroxyl radical and peroxyl radical. Total phenolic contents of Sanguisorbae radix extract at concentrations of 0.5 and 5 mg/mL were 0.50 and 3.33 mM gallic acid equivalents, respectively. Sanguisorbae radix extract at concentration of 0.01, 0.1 and 0.5 mg/mL inhibited 0.2 mM tert-butyl hydroperoxide-induced cytotoxicity by 33.8, 79.1 and 96.9%, respectively, in HepG2 cell culture system. Thus, strong antioxidant and cytotoxicity-ihnibiting effects of Sanguisorbae radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in total phenolic contents.

• The Pure and Applied Mathematics
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• v.24 no.1
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• pp.33-34
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• 2017

$Fo{\check{s}}ner$ [1] defined a module left (m, n)-derivation and proved the Hyers-Ulam stability of module left (m, n)-derivations. In this note, we prove that every module left (m, n)-derivation is trival if the algebra is unital and $m{\neq}n$.

• Journal of the Chungcheong Mathematical Society
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• v.33 no.1
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• pp.133-146
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• 2020

In this paper, we established the complete moment convergence for sequences of m-pairwise negatively quadrant dependent random variables which are weakly upper bounded by a random variable X.