• Journal of Ginseng Research
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• v.22 no.2
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• pp.91-95
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• 1998

The distribution of phenolic components of Korean ginseng (Panax ginseng KG) and American ginseng (Panax quinquefolium, AG) were compared by thin-layer chromatography (TLC). Silica gel TLC gave 3~4 spots, while $NH_2$ HPTLC 5~6 spots, which were colored by both $FeCl_3$/$K_3Fe(CN)_6$ and Folin-Ciocalteu. The distribution of phenolic components was quite different between KG and AG. Especially, a polyphenol (m.w. 578), which had been isolated from KG by the author, was not found in AG. This result suggests that the polyphenol could be used as an index compound for the differentiation of KG from AG.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.1
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• pp.58-66
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• 2019

Static compound parabolic collectors (CPCs) have advantages such as ease for fabrication and lower cost compared with other concentrating collectors. In this study, thermal performance analysis of CPC employing heat storage tank was carried out. The clearness index and capacity of heat storage tank are taken as the main parameters for numerical simulation. The effects of the parameters on the hourly and daily system performances ncluding the useful energy, heat loss, and collector efficiency were numerically investigated. Results showed that the system has a potential for efficient recovery of solar thermal energy.

• International Commerce and Information Review
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• v.16 no.4
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• pp.439-455
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• 2014

Korea-Japan trade has been trade deficit for a long time and therefore this matter must be a settled urgently for continuous economic growth of Korea. For reasons mentioned above, this study pays attention to Japan materials industry which has induced trade deficit in the Korea-Japan trade and this study analyzed competitiveness of Japan materials industry in the Korea market. This study special regard will be paid to the Compound and Chemical Products in Japan materials industry. For attaining the purpose of study, we collected related statistical data and Market Share Index, Trade Specialization Index and Market Comparative Advantage Index used in study methodology From this analysis, we found that most of Japan material products have competitiveness in Korea market and chemical products used in photography & photo sensitized materials, paint & printing ink products particularly have very strong competitiveness in Korea Market.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.2
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• pp.91-95
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• 2019

A new experimental approach is proposed to detect a specific polymer dissolved in a liquid. Distinctive optical properties were found using a laser scattering technique when there is a polymer compound with almost no difference in optical properties (index of refraction) in a liquid phase. The index of refraction, which determines the refraction of light, is obtained by dissolving PCL and PLA. The used samples are biodegradable materials with similar properties and dissolved in a mixture of Chloroform 7: Methanol 3. To predict the optical properties, a 632-nm diode laser was used as the light source of the device, and an integrating sphere was used as the light receiver. Although PCL and PLA had a similar index of refraction of 1.46-1.48, the dissolved PCL showed a relative transmittance of 43%, and the dissolved PLA had a relative transmittance of 34%. The difference in optical properties of the pure polymer compound in the solid state or liquid state is not significantly different, and the difference in the dissolved state in the specific solvent is remarkable because the solubility differs in a specific solution and is randomly distributed.

• Clean Technology
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• v.23 no.4
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• pp.378-387
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• 2017

To obtain epoxy resin with permanently attached flame-retardant groups, phosphorus compound containing di-hydroxyl group [10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phospha phenanthrene-10-oxide, DOPO-HQ] and silicone compound containing di-hydroxyl group (polydimethylsiloxane, hydroxyl terminated, PDMS) were reacted with uncured epoxy prepolymer (diglycidyl ether of bisphenol A, DGEBA) and then cured using 4,4-diaminodiphenylmethane (DDM) as a crosslinking agent. The properties of the resulting epoxy materials were characterized using Fourier transform infrared (FTIR) spectrometer, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), limiting oxygen index (LOI) test/vertical burning test (UL 94-V test), tensile properties test and impact test. This study examined the effect of phosphorus/silicone compound contents on the thermal/mechanical properties and flame retardancy of cured epoxy resins containing phosphorus and silicone compounds. It was found that the thermal/mechanical properties of epoxy resins containing phosphorus and silicone components were higher than those of simple epoxy resin. The flame-retardancy (LOI: 29.9 ~ 31.8% and UL 94-V: V-0) of all samples containing phosphorus compound and phosphrous compound/silicone compound was found to be passed the flame-retardant requirements (LOI: > 30%, UL 94-V: V-0) of LOI and vertical burning tests. However, the flame-retardancy (LOI: 21.4% and UL 94-V: no rating) of simple epoxy resin was found to be failed the flame-retardant requirements.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.3
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• pp.61-72
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• 2005

The main purpose of this study is to develop air transportation cultural index which is able to estimate the level of them. Generally Speaking, air transportation cultural, a compound word of 'air transportation' and 'culture', is a substantial entity consisting knowledge, art, morality, legality, cultivation, customs, and etc, which comes from aircraft operation sector, airport operation/management sector and user sector. They are classified in a primary scope, as aircraft operation sector relating to flight operation, airport operation/management sector and user sector. The research and analysis were taken approximately 4 months, from June 2004 to October 2004. To evaluate the index, the detailed item for three categories were chosen and quantified. The grades for each items were induced from calculation formula for air transportation cultural index by applying weight values. The final grade of Korea's air transportation cultural index recorded 63.19 points.

• Natural Product Sciences
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• v.24 no.2
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• pp.88-92
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• 2018

The present study was undertaken to investigate the isolated compounds from the stem bark of Garcinia atroviridis as potential cholinesterase inhibitors and the ligand-enzyme interactions of selected bioactive compounds in silico. The in vitro cholinesterase results showed that quercetin (3) was the most active AChE inhibitor ($12.65{\pm}1.57{\mu}g/ml$) while garcinexanthone G (6) was the most active BChE inhibitor ($18.86{\pm}2.41{\mu}g/ml$). It is noteworthy to note that compound 6 was a selective inhibitor with the selectivity index of 11.82. Molecular insight from docking interaction further substantiate that orientation of compound 6 in the catalytic site which enhanced its binding affinity as compared to other xanthones. The nature of protein-ligand interactions of compound 6 is mainly hydrogen bonding, and the hydroxyl group of compound 6 at C-10 is vital in BChE inhibition activity. Therefore, compound 6 is a notable lead for further drug design and development of BChE selective inhibitor.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1288-1294
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• 2021

There are a growing number of reports of hospital-acquired infections caused by pathogenic bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). Many plant products are now being used as a natural means of exploring antimicrobial agents against different types of human pathogenic bacteria. In this research, we sought to isolate and identify an active molecule from Sedum takesimense that has possible antibacterial activity against various clinical isolates of MRSA. NMR analysis revealed that the structure of the HPLC-purified compound was 1,2,4,6-tetra-O-galloyl-glucose. The minimum inhibitory concentration (MIC) of different extract fractions against numerous pathogenic bacteria was determined, and the actively purified compound has potent antibacterial activity against multidrug-resistant pathogenic bacteria, i.e., MRSA and its clinical isolates. In addition, the combination of the active compound and β-lactam antibiotics (e.g., oxacillin) demonstrated synergistic action against MRSA, with a fractional inhibitory concentration (FIC) index of 0.281. The current research revealed an alternative approach to combating pathogenesis caused by multi-drug resistant bacteria using plant materials. Furthermore, using a combination approach in which the active plant-derived compound is combined with antibiotics has proved to be a successful way of destroying pathogens synergistically.

• Fire Science and Engineering
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• v.33 no.4
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• pp.16-27
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• 2019

A burning test was conducted on the smoke and combustion gases generated from cypress wood treated with sodium silicate, 3-aminopropyltrimethoxysilane sol, 3-(2-aminoethylamino)propylmethyldimethoxysilane sol, and 3-(2-aminoethylamino) propyltrimethoxysilane sol. The silicone compound sol was applied to each of the cypress wood specimens three times with a brush. The smoke and combustion generation gas were analyzed using a cone calorimeter (ISO 5660-1) and the smoke was also evaluated by applying new smoke risk assessment method. The smoke performance index (SPI) of the cypress treated with silicone compound increased 1.66 to 8.42 times and the smoke growth index (SGI) was 11.8 to 88.2%, respectively. The smoke intensity (SI) is expected to be 1.0~50.5% lower than that of the base specimens, resulting in lower smoke and fire hazards. The third maximum carbon monoxide (CO_peak) concentration of the specimens treated with silicone compounds was 22.5~33.3% lower than that of the base specimens. On the other hand, it produced potentially fatal toxicity that was 1.48~1.72 times higher than the US Occupational Safety and Health Administration (OSHA) acceptance standard (PEL). Cypress wood itself produced a high carbon monoxide concentration, but the silicon compound played a role in reducing this level.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.467-476
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• 2011

Compound noun phrase (CNP) is important factor for semantic information process because the meaning of the CNP is more disambiguous than that of single word. However, the CNP can be expressed in various types even though it expresses same meaning. It is called syntactic diversity. It makes information system difficult to grasp sense identity. In order to resolve the syntactic diversity in this research, we propose an indexing method for compound noun phrase. The main purpose is to make identical index term for various types of CNPs which has same meaning. To do so, the research follows next steps. For the first, we make rule template and utilize the template to extract CNPs from set of domestic research papers. In general, the CNP has a unique meaning. Considering the characteristic, we suggest synthesis rules of index terms and apply the rule to CNPs extracted in previous step. For the objective performance evaluation of the research, a test set, HANTEC 2.0, was utilized and the result was compared to baseline model. Through the experiment and the evaluation, we have confirmed that the indexing method suggested in this paper could positively affect retrieval precision and improve performance of the information retrieval.