• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.397-403
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• 2009

In this paper, an exciter current control of a synchronous generator for ships using a compound type digital automatic voltage regulator (DVAR) in order to provide a constant output voltage of the generator is presented. The compound type DAVR is composed of a controller part to adjust output voltage and an power source unit to supply power to the exciter. The controller part, which generates the PWM switching pattern via the PI controller, drives a power MOSFET for bypass to limit the SG's exciter current. The power source unit part is parallel connected to an output terminal of the generator through a reactor and a power CT. The residual magnetic flux of SG provides exciter current to the exciter through the reactor during the initial running or no load state and load current supplies field current to the exciter through the power CT during loading state. This paper confirmed an experiment to verify the validity of compound type DAVR system for controlling output voltage of synchronous generator.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.26-31
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• 2010

This research does focus on realization of customizing recommendation service that all of formal, or informal learning is accomplished at real time according to worker's current situation or business context corresponding with the individual ability and the learning progress at industry or education field. For this, we designed the customizing intelligent recommendation system based on compound knowledge that workers can listen to coaching advices at real time and to retrieve and recommend multidimensional relation easily. Also, we constructed the repository based on compound knowledge and process engine for efficient management of compound knowledge. In specific industry, expert solution or coaching service will be created using the knowledge which is accumulated in long-term.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.103-109
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• 1993

Acornic powder was extracted with methanol and ethylacetate to obtain a crude acornic compounds. And they were examined concerning their antioxidant activities for linoleic acid. The results were as follows: 1. Hydrogen donating activity for DPPH was higher in 100ppm acornic compound than 100ppm BHT and 100ppm ${\alpha}$-tocopherol. 2. When the 100ppm acornic compound was added to linoleic acid, which was heated at $50^{\circ}C$ for 48 hours, antioxidant activities by POV and TBA was higher than that of 100ppm ${\alpha}$-tocopherol, but the effect was almost the same as the 100ppm BHT. 3. Antioxiodant activity of acornic compound showed synergistic effect along with malic acid, citric acid, tartaric acid, alanine, arginine, histidine, lysine-HCl, galactose, maltose, glucose and sucrose. 4. Acornic compound inhibited peroxidation of linoleic acid induced by heavy metals.

• Journal of Korea Foundry Society
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• v.26 no.3
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• pp.123-128
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• 2006

Mechanical and thermal properties of spray-cast hypereutectic Al-20wt.%Si-xwt.%Fe alloys (x=0, 1, 3, 5) were investigated. After the spray-casting, hot extrusion was performed at $400^{\circ}C$. Intermetallic compound (${\beta}-Al_5FeSi$) and primary Si are observed in the spray-cast aluminum alloys. The size of primary Si and intermetallic compound of the spray-aluminum alloys became finer and more uniformly distributed than that of the permanent mold cast ones. Ultimate tensile strength of the spray-cast aluminum alloys increased by increasing Fe contents, but that of the permanent mold cast aluminum alloys decreased by increasing Fe contents possibly due to increased amount of coarse intermatallic compound. The coefficient of thermal expansion (CTEs) of the aluminum alloys became lower with finer primary Si and intermetallic compound, and this is attributed to the increased amount of interfacial area between the aluminum matrix and the phases of finer Si and intermetallic compound.

• Korean Journal of Cognitive Science
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• v.6 no.3
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• pp.65-81
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• 1995

Compound nouns as a composition of multiple nouns exhibit diverse occurence patterns in the texts and have varying degree of meaning coherence.The problem of compound nouns in information retrieval is to find a method to represent and identify the compositive patterns of each words.This paper explains how the cooccurrence patterns are related with the meaning of each compound noun and the information of such relations that can be mechanically acquired from texts is used in ranking the candidated documents for a given query.The main theme of the paper is that compound nouns can be categorized according to their occurrence patterns of simple nouns and these occurrence patterns can be formalized by statistical analysis without large dictionary or complex compositive rules.Our suggested model achieved about 7.75% improvement over the best precision of the other methods at each recall measurements on Korean test collection.

• Journal of Integrative Natural Science
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• v.6 no.3
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• pp.163-169
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• 2013

The chemokine receptor CCR1 a GPCR super family protein contains seven transmembrane domains. It plays an important role in rheumatoid arthritis, organ transplant rejection, Alzheimer's disease and also causes inflammation. Because of its role in disease processes, antagonism of CCR1 became an attractive therapeutic target. In the current study, we have taken a novel series of recently reported CCR1 antagonist of 1-(4-Phenylpiperazin-1-yl_-2-(1H-Pyrazol-1-yl) ethanone derivatives and performed a HQSAR analysis. The model was developed with Atom (A) and bond (B) parameters and with different set of atom counts to improve the model. The results of HQSAR showed good predictive ability in terms of $r^2$ (0.904) and $q^2$ (0.590) with 0.710 as standard error of prediction and 0.344 as standard error of estimate. The contribution map depicted the atom contribution in inhibitory effect. Compound-14 which was reported to be a highly active compound showed positive atom contribution in three R groups ($R^3$. $R^{5a}$ and $R^{2b}$) in inhibitory effect, which could be the reason why this compound is highly active compound whereas, the lowest active compound-6 showed negative contribution to inhibitory effect.

• International Journal of Highway Engineering
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• v.16 no.3
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• pp.51-57
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• 2014

PURPOSES : This study is to suggest tunnel length to spray curing compound, based on the field tests. METHODS : At first field test, length from the entrance of tunnel to wet wall was checked by visual survey. The second and third test, various sensors were installed in concrete or in tunnel, such as RH sensor, temperature sensor, portable weather station and etc.. And also, test for bleeding and retaining water of concrete were conducted to evaluate environmental effect on concrete pavement. RESULTS : The result of the field experiment for tunnel length to spray curing compound indicates that length changes depending on tunnel length, season, and location. Environmental condition of a short tunnel was not much different between location near entrance and at center of tunnel. However, in case of a medium and long tunnel, effect of outside environmental condition decreased, when location moved into tunnel center of it. CONCLUSIONS : From the testing results, it can be proposed that optimum tunnel length to spray curing compound is 60m for a medium and long tunnel, and whole length for a short tunnel.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.487-492
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• 2002

The growth kinetics of intermetallic compound layers formed between eutectic Sn-58Bi solder and (Cu, electroless Ni-P/Cu) substrate were investigated at temperature between 70 and 120 C for 1 to 60 days. The layer growth of intermetallic compound in the couple of the Sn-58Bi/Cu and Sn-58Bi/electroless Ni-P system satisfied the parabolic law at given temperature range. As a whole, because the values of time exponent (n) have approximately 0.5, the layer growth of the intermetallic compound was mainly controlled by volume diffusion over the temperature range studied. The apparent activation energies of Cu$_{6}$Sn$_{5}$ and Ni$_3$Sn$_4$ intermetallic compound in the couple of the Sn-58Bi/Cu and Sn-58Bi/electroless Ni-P were 127.9 and 81.6 kJ/mol, respectively.ely.

• Advances in Traditional Medicine
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• v.2 no.1
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• pp.58-63
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• 2002

The effect of the aqueous extract of Rubus coreanus Miq. (Rosaceae) fruits (AERC) on anaphylactic reaction was investigated. AERC completely inhibited compound 48/80-induced systemic anaphylactic shock at dose of 0.1 to 1.0 g/kg. When AERC was pretreated at concentrations ranging from 0.01 to 1.0 g/kg, the plasma histamine levels induced by compound 48/80 were reduced in a dose-dependent manner. AERC also inhibited the histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. The level of cAMP in RPMC, when AERC (1.0 mg/ml) was added, transiently and significantly increased about 6-fold compared with that of basal cells. These results indicate that AERC may be beneficial in the treatment of non-specific anaphylactic reactions.

• 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.