• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.137-141
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• 2004

Many monopropellant thrusters use a catalyst for decompose the propellant, hydrazine. The catalyst directly affects the thruster performances and lifetime. Therefore, it is important to confirm that the catalyst is suitable for our thrusters. Until 2002, we used She1l405 catalyst, for satellite RCS thrusters, and H-IIA and M-V launch vehicle upper-stage RCS thrusters. In 2002, however, Shell Chemical Inc. ceased manufacturing She1l405 catalyst and transferred the product to AEROJET, where it was renamed S405. We subsequently investigated the characteristics of AEROJET's S405 catalyst and SOLVAY's KC12GA catalyst, (SOLVAY is a Belgian chemical company, and KC12GA is used for ASTRIUM's thruster) and conducted thruster firing tests using the new catalysts. After conducting, we confirm that the KC12GA catalyst was suitable for our thrusters, and decided to use KC12GA for two satellite programs.

• Journal of the Korean Vacuum Society
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• v.17 no.3
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• pp.211-214
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• 2008

GaN-based light-emitting diodes (LEDs) of a 405 nm wavelength have been fabricated on a sapphire substrate by metal organic chemical vapor deposition (MOCVD). In order to reflect the photons, which are generated in the InGaN active region and emitted to the backside, to the front surface, a reflection layer was deposited onto the back of the substrate. Aluminum was used as the reflection layer and Al was deposited on the sample followed by Ti evaporation for firm adhesion of the reflection layer to the substrate. The light extraction efficiency was enhanced 52 % by adoption of the Ti-Al reflection layer.

• KSBB Journal
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• v.15 no.2
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• pp.150-155
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• 2000

Antioxidative activity of c비ture of Streptomyces sp. BH-405 was investigated. After removal of pellets of Streptomyces sp. B BH-405, antioxidative substances were is미ated and suc$\infty$sively purified from culture of Streptomyces sp. BH-405 by by thin | layer chromatography $\pi$LC) or silica gel column chromatography. The fraction 3 obtained from ethylether fractionation of the C culture appeared highest level of anti oxidative activity as determined by thiocyanate method. Band 2 obtained by further P purification of this fraction showed higher anti oxidation level than that of same concentration of dl- $\alpha$ -tocopherol, butylated h hydroxy anisole (BHA). The band 2 showed higher rate of 1, 1.diphenyl 2-picrylhydrazyl (DPPH) decolorization than dl-$\alpha$-tocopherol. In the rat liver microsomes, band 2 rapidly inhibited lipid peroxidation which was initiated enzymatically by r reduced nicotinamide adenine dinucleotide phosphate (NADPH) or non-enzymatically by Fenton’s reagent. Band 2 inhibited on | lipid peroxidation of mitochondria or the linoleic acid hydro peroxide induced peroxidation system. It is concluded that band 2 obtained by fractionation of Streptomyces sp. BH-405 cultivation contained antioxidants with the capacity to inhibit oxidative m modification.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.28-35
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• 1998

An antimicrobial peptide producing bacterium, Bacillus subtilis A405, was screened and identified among 700 of antagonistic bacteria. The heat-resistant antimicrobial peptide, AMP-405, was purified from the broth culture of B. subtilis A405 through $20{\sim}40%$ ammonium sulfate precipitation and ultrafiltration. The AMP-405 exhibited strong antimicrobial activities against Botrytis cinerea, Cercospora sp., Fusarium oxysporum, Penicillium digitatum, Celletotrichum gloeosporioides, Rhizoctonia solani, Pythium ultimum, Pyricularia oryzae, Escherichia coli, Pseudomonas spp. and Candida albicans. The molecular weight of the peptide was about 3.0 kDa determined by SDS-PAGE, Native-PAGE and Tris-Tricine gradient electrophoresis, and composed of 9 kinds of amino acid such as aspartic acid, glycine, serine, glutamine, valine, leucine, isoleucine, proline, tyrocine. To determine the efficiency of AMP-405 as a potential maintenance of fruits freshness, cherry tomato was srored at $25^{\circ}C$ for 2 weeks after treatment with $50{\mu}g/ml$ of AMP-405 and $10^{5}$ spores/ml of Botrytis cinerea simultaneously. Treatment with AMP-405 resulted in significantly less infection by Botrytis cinerea, than the treatment with tap water as a control.

• The Journal of Information Technology
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• v.6 no.3
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• pp.65-73
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• 2003

The evaluation AP embedded Linux board is implemented. The board is made of IBM 405 GP processor, PPCBoot-1.2.1 boot loader, Linux-2.4.21 kernel and root file system. The evaluation board has two flash memories, boot flash and application flash of size 512Kbyte and 16Mbyte, respectively. And it supports IEEE 802.11a which provide the maximum throughput of 54Mbps in the 5.2GHz frequency band. MTD(Memory Technology Device) and JFFS2(Journalling Flash File System version 2) technologies are adopted to optimally package the system software, boot loader, kernel and root file system. And in order to optimize root file system, busybox package and tiny login are used. Linux kernel and root file system is combined together with mkimage utility.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.319-324
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• 2014

The aim of this study was to evaluate influences of titanium dioxide ($TiO_2$) concentrations and irradiation times on growth of Streptococcus mutans when irradiated by visible light (405 nm wavelength) and by ultraviolet light (254 nm wavelength). To find the optimal antibacterial concentration of $TiO_2$, 0.01, 0.1, 1.0, and 10.0 mg/ml $TiO_2$ suspension was prepared with sterilized distilled water. S. mutans cultured media was added to $TiO_2$ solution to set the final cell count to $10^4CFU/ml$. The photocatalytic reaction was induced by irradiating 254 nm and 405 nm lights for 10 minutes. To compare the bactericidal activities according to irradiation times, all photocatalytic reaction was carried out with 0.1 mg/ml $TiO_2$ for 0, 10, 20, 30, and 40 minutes with both lights. After the photocatalytic reaction, $100{\mu}m$ of the reaction mixture was immediately plated on brain heart infusion agar. These plates were placed at 5% $CO_2$, $37^{\circ}C$, for 24 hours and the bacterial colonies were counted. All experiments were performed in quintuplicate. One-way ANOVA was used to determine whether there were any significant differences between the $TiO_2$ concentrations or the irradiation times. The most effective concentration of $TiO_2$ for its photocatalytic bactericidal effect on S. mutans was 0.1 mg/ml when irradiated with 254 nm and 405 nm lights. The longer the irradiation time, the bigger the bactericidal effect for both wavelengths. Over 99% of bacteria in the inoculum were killed after irradiation with 254 nm for 20 minutes and with 405 nm for 40 minutes. In conclusion, a photocatalytic reaction of $TiO_2$ induced by visible light of 405 nm constitutes the bactericidal effect on S. mutans.

• Communications of the Korean Mathematical Society
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• v.25 no.3
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• pp.405-417
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• 2010

We prove the generalized Hyers-Ulam stability of the generalized quadratic functional equation $$f(rx\;+\;sy)\;=\;r^2f(x)\;+\;s^2f(y)\;+\;\frac{rs}{2}[f(x\;+\;y)\;-\;f(x\;-\;y)]$$ in fuzzy Banach spaces, where r, s are non-zero rational numbers with $r^2\;+\;s^2\;{\neq}\;1$.

• Journal of Animal Science and Technology
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• v.44 no.5
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• pp.625-632
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• 2002

Livestock farmers face several limitations when using the government recommended sorghum cultivars for forage because of the limited seed supply. Therefore, the objective of the this study is to evaluate, select, and recommend the best high-yielding hybrid as the government recommended cultivars. The agronomic characteristics and forage yield of three cultivars (cv. P947, cv. KF429 and cv. SS405) of forage sorghum were evaluated at two locations (Suwon and Sunghwan) for 2 years (1999${\sim}$2000). 'KF429' was susceptible to foliar disease, while 'SS405' had less lodging resistance among the sorghum cultivars tested. When compared with 'P947' (recommended cultivar), dry matter yield of 'KF429' and 'SS405' cultivars increased by 16% and 75%, respectively. The crude protein of 'P947'(9.4%) was higher than other cultivars. The percentage of ADF and NDF were the lowest in 'KF429' cultivar. The results of forage performance experiment indicate that 'KF429' and 'SS405' are recommended as the government recommended sorghum cultivars due to a high lodging tolerance, disease resistance, and high dry matter yield.

• Journal of the Korean Mathematical Society
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• v.42 no.3
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• pp.405-434
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• 2005

We establish appropriate $L^p$ estimates for a class of maximal operators $S_{\Omega}^{(\gamma)}$ on the product space $R^n\;\times\;R^m\;when\;\Omega$ lacks regularity and $1\;\le\;\gamma\;\le\;2.\;Also,\;when\;\gamma\;=\;2$, we prove the $L^p\;(2\;{\le}\;P\;<\;\infty)\;boundedness\;of\;S_{\Omega}^{(\gamma)}\;whenever\;\Omega$ is a function in a certain block space $B_q^{(0,0)}(S^{n-1}\;\times\;S^{m-1})$ (for some q > 1). Moreover, we show that the condition $\Omega\;{\in}\;B_q^{(0,0)}(S^{n-1}\;\times\;S^{m-1})$ is nearly optimal in the sense that the operator $S_{\Omega}^{(2)}$ may fail to be bounded on $L^2$ if the condition $\Omega\;{\in}\;B_q^{(0,0)}(S^{n-1}\;\times\;S^{m-1})$ is replaced by the weaker conditions $\Omega\;{\in}\;B_q^{(0,\varepsilon)}(S^{n-1}\;\times\;S^{m-1})\;for\;any\;-1\;<\;\varepsilon\;<\;0.$

• KSBB Journal
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• v.15 no.2
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• pp.156-161
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• 2000

This study was designed to investigate the antioxidative activity on oxidation of human low density lipoprotein(LDL) of band 2 fractionated from culture broth of Streptomyces sp. BH-405. Antioxidative activity of band 2 obtained from fractionation of BH-405 culture purification was measured against $Cu^{2+}$ mediated human LDL oxidation by thiobarbituric acid reactive substance. $CuSO_4$ mediated oxidation of LDL was degraded at a much higher rate than native LDL. Band 2 at a concentration of 100 or 200 !lg/mL inhibited the oxidation of LDL induced by $CuSO_4$, The formation of conjugated dienes induced in the presence of 5 !1M CuS04 of the mouse macrophage and J744. The electrophoretic mobility of the LDL in addition of $200\mu\textrm{g}$ band 2 in the presence of $5\mu\textrm{m}$ $CuSO_4$ was lower than that of native LDL. LDL modified by copper mediated or cell mediated uptake was degraded by macrophage at much greater than native LDL, and band 2 was found as potential inhibitor of modification of 125I-labelled LDL by macrophage. phage.