• The KIPS Transactions:PartC
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• v.12C no.5 s.101
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• pp.659-664
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• 2005

Advanced countries overhaul government workflows using IT, which not only enhances efficiency and productivity, but paves the way to a 'e-Government' offering prompt, quality service for citizens. This research analyzes the DiD(Defense-in-Depth Strategy) and compares the information protection strategy of Korean e-Government with DiD for reliable and safe e-Government's build.

• Earthquakes and Structures
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• v.6 no.1
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• pp.45-69
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• 2014

The 2009 L'Aquila, Italy earthquake shook a high density area causing a wide spectrum of damage to reinforced concrete with infill buildings, one of the most common building types used in Italy. The earthquake has proven to be a "full-scale" laboratory to further understand building performance. This paper presents the first results of a joint research effort between the University of Bologna and Degenkolb Engineers, aimed at investigating the seismic behavior of an infilled frame building that collapsed during the earthquake. State-of-the-practice techniques were implemented as a way to determine the reliability of these modeling techniques in anticipating the observed building performance. The main results indicate that: (i) the state-of-the-practice techniques are able to predict the observed behavior of the buildings; (ii) the masonry infills have a great influence on the behavior of the building in terms of stiffness, strength and global ductility.

• Journal of ILASS-Korea
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• v.2 no.4
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• pp.1-6
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• 1997

In the case of analyzing the combustion phenomena in a small high speed DI diesel engine, one demands the experimental results of the impinging spray on the wall as a basic characteristics. In the experiments presented here, diesel fuel oil was injected into a high pressure chamber in which compressed air at room temperature was charged. The single spray was impinged on a flat wall. The growth of the spray was photographed with transmitted light or scattered light. The effect of the spray axis angle to the wall on the impinging spray was revealed. Finally, the experimental results was presented, that is, the radius and height of the impinging spray was influenced by above mentioned variable.

• Journal of ILASS-Korea
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• v.10 no.3
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• pp.45-53
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• 2005

The purpose of this study is to analyze that intake port swirl and fuel injection system have an effect on the engine performance in a turbocharged D.I. diesel engine of the displacement 9.4L. As result of steady flow test, when the valve eccentricity ratio moved to cylinder wall, the flow coefficient and swirl intensity is increased. And as the swirl is increased, the mean flow coefficient is decreased, whereas the Gulf factor is increased. Through this engine test, it can be expected to meet performance and emissions by the following applied parameters; the swirl ratio is 2.43, injection timing is BTDC 13oCA and compression is 15.5.

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.319-322
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• 2008

The viability of acetylene addition in each step of aromatic formation initiated by vinyl radical and acetylene also with its competition with structure rearrangement is investigated by determining optimal geometries and barrier and reaction energies using quantum mechanical methods. In principle, the addition reaction has more difficult in term of free energy and enthalpy compared to geometry arrangement. Under combustion conditions, i.e. T = 1200 K, acetylene addition is unfavorable mechanism as the barrier energy values rise much higher than that of geometry arrangement. However, in longer chain hydrocarbon case, e.g. n-CxHx+1 where x ³ 8, C-C bond rotation is rather difficult and requires high energy to form a ring structure, elongation chain is preferable.

• Korean Journal of Plant Resources
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• v.20 no.3
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• pp.221-225
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• 2007

The plant Ligularia fischeri var. spiciformis (Compositae) is a candidate for available functional foods. It has been used to treat diabetes mellitus and rheumatoid arthritis. We have reported the isolation of a new eremophilanolide named 6-oxoeremophilenolide and cytotoxic intermedeol together with the isolation of hydrophilic constituents, chlorogenic acid, 3,4-di-O-caffeoylquinic acie (3), and 5-O-[1-butyl]-3,4-di-O-caffeoylquinic acid. Compound 3 was again isolated by combination of silica gel- and ODS column chromatography for the anti-nociceptive action. Compound 3 and 4 were assayed in hot plate- and writhing tests in the rat. Although the three derivatives of caffeic acid exhibited significant anti-nociceptive effects at 10 mg/kg dose (i.p.),(activity potency: 4>3). These results suggest that compound 3 is responsible for at least rheumatoid arthritis, and caffeic acid moiety is the active moiety of dicaffeoylquinic acid.

• Applied Biological Chemistry
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• v.3
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• pp.25-48
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• 1962

The polysaccharide C prepared from gum tragacanth powder (U. S. P. grade) by the precipitation method with 85% ethanol was a neutral polysaccharide, $[{\alpha}]^{30}_D-72.2$. The polysaccharide C consisted of L-rhamnose, D-xylose, L-arabinose and D-galactose in the molar ratio 2:1:17:9 (Table 1, 2, 3, ). The polysaccharide C was methylated with dimethylsulphate and 40% NaOH, and Purdies regent. The hydrolyzate of fully methlated product ($[{\alpha}]^{22}_D-102$ in chloroform, the methoxy content 40.6%) was composed of 2, 3, 5-tri-O-methyl-L-arabofuranose (I), 3,4-di-O-methyl-L-rhamnopyranose (II), 2,3-di-O-methyl-D-xylose (III), 2,3,4-tri-O-methyl-D-galactopyranose (IV), 2,4-di-O-methyl-L-arabopyranose (?), 2,4-di-O-methyl-D-galactose(VI), 2-O-methyl-D-arabinose (VII), and L-arabopyranose(VIII) (Table 4, 5, and Fig. 4). The first partial hydrolysis (A) of the polysaccharide C with 0.05N-HCl for 4.5 hours at $80-85^{\circ}C$ released only L-arabinose: the second hydrolysis (B) with 0.1N-HCl for 5 hours at $80-85^{\circ}C$, L-arabinose and D-galactose; and the third hydrolysis (C) with 0.3N-HCl at $90-95^{\circ}C$ in sealed tube, L-rhamnose, D-xylose, L-arabinose and D-galactose. From the unhydrolyzate A' were found L-rhamnose, D-xylose, L-arabinose, and D-galactose; from B' L-rhamnose, d-xylose, L-arabinose and D-galactose; and from C' D-xylose and D-galactose respectively (Table 6). The periodate consumption and formic acid production of the polysaccharide C were measured at various time intervals. After 120 hours periodat was consumed by 1.23 mole per $C_5H_8O_4$ and formic acid was produced 0.78 mole per $C_5H_8O_4$ (Table 7). Although a definite chemical structure for this polysaccharide C may not be formulated, experimental data, especially, from methylation, partial hydrolysie and determination of its molar ratio, and periodate analysis showed that the polysaccharide C is a highly branched polysaccharide and would be constructed of galactoaraban as a main chain residue and L-arabofuranose, D-galactopyranosyl $(1{\rightarrow}1)$-L-arabofuranose, D-xylopyranosyl $(1{\rightarrow}2)$-L-rhamnopyranosyl $(1{\rightarrow}1)$-L-arabofuranose, and L-rhamnopyranosyl $(1{\rightarrow}1)$-arabofuranose, and D-galactopyranosyl-$(1{\rightarrow}2)$-L-arabopyranosyl-$(1{\rightarrow}1)$-I-arabofuranose as a branch chain or end group (page 21).

• Advances in aircraft and spacecraft science
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• v.9 no.3
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• pp.195-215
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• 2022

The increasing interest in CubeSat platforms ant their capability of enlarging the frontier of possible missions impose technology improvements. Miniaturized electrical propulsion (EP) systems enable new mission for multi-unit CubeSats (6U+). While electric propulsion systems have achieved important level of knowledge at equipment level, the investigation of the mutual impact between EP system and CubeSat technology at system level can provide a decisive improvement for both the technologies. The interaction between CubeSat and EP system should be assessed in terms of electromagnetic emissions (both radiated and conducted), thermal gradients, high electrical power management, surface chemical deposition, and quick and reliable data exchanges. This paper shows how a versatile CubeSat Test Platform (CTP), together with standardized procedures and specialized facilities enable the acquisition fundamental and unprecedented information. Measurements can be taken both by specific ground support equipment placed inside the vacuum facility and by dedicated sensors and subsystems installed on the CTP, providing a completely new set of data never obtained before. CTP is constituted of a 6U primary structure hosting the EP system, representative CubeSat avionics and batteries. For the first test campaign, CTP hosts the ambipolar plasma propulsion system, called Regulus and developed by T4I. After the integration and the functional test in laboratory environment, CTP + Regulus performed a Test campaign in relevant environment in the vacuum chamber at CISAS, University of Padua. This paper is focused on the test campaign description and the main results achieved at different power levels for different duration of the firings.

• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.373-378
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• 2015

The solvolysis rate constants of di-n-butyl phosphorochloridate ((CH₃CH₂CH₂CH₂O)₂POCI, 1) in 28 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N_T solvent nucleophilicity scale and Y_Cl solvent ionizing scale, with the sensitivities values of 1.40 and 0.42 for l and m, respectively. These l and m values can be considered to support an S_N2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH^≠ (8.0 to 15.9 kcal·mol⁻¹ ) values and large negative ΔS^≠ (−25.8 to −53.1 cal·mol⁻¹ ·K⁻¹ ) values, the Kivinen’s n values (0.9~1.7), and the solvent kinetic isotope effect (1.62).

• Journal of Life Science
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• v.28 no.5
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• pp.509-516
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• 2018

Five phenolic compounds were isolated from the ethyl acetate fraction of leaves from Stewartia koreana, and their nitric-oxide (NO) inhibitory activities were measured to identify the major active constituents responsible for the efficacy of the extract against inflammatory reactions. These five compounds were quercetin (1), quercitrin (2), hyperin (3), quercetin-3-O-(6"-O-galloyl)-${\beta}$-D-galactopyranoside (4), and kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside (5). Among the separated compounds in the EtOAc fraction, compounds 4 and 5 were isolated for the first time, and no study has yet reported their anti-inflammatory effects. The compounds were identified by spectroscopic analysis, and the isolated compounds showed significant NO inhibitory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Compound 5 showed the most potent inhibitory effect (63.35% inhibition) against LPS-induced NO production compared to that of compound 1 (17.17%), compound 2 (5.0%), compound 3 (3.92%), and compound 4 (6.32%) at $10{\mu}g/ml$ concentration. NO production was inhibited by suppressing the protein expression of inducible nitric-oxide synthase in LPS-stimulated RAW 264.7 macrophages. These results indicate that kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside might be the major active compound responsible for the anti-inflammatory effects of S. koreana.