• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.150-159
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• 2011

This study was conducted to gather the basic data on the alpine leek (Allium victorialis) for the expand of consumption and the production of its manufactured goods. Amino acid content in alpine leek leaves and various physiological activities were examined. Seventeen component amino acids and 38 free amino acids from alpine leek leaves were analyzed, and the total contents were 2,693.28 mg/100g for component amino acids and 535.39 mg/100g for free amino acids. Total phenolic compounds in the leaves of alpine leek showed the highest level from the methanol extract (37.7 mg/l), and followed by ethanol extract (31.9 mg/l) and hot water extract (25.4 mg/l). Total flavonoid contents in 1,000 mg/l extract was the highest in the methanol extract (22.2 mg/l). DPPH radical scavenging activity at 1,000 mg/l extract was high in the order of ethanol extract (51.6%), methanol extract (47.3%) and hot water extract (37.2%). nitrite radical scavenging activity Methanol extract from Allium victorialis leaves was the highest nitrite radical scavenging activity (79.5%). Hyperplasia suppression of lung cancer cells (Calu-6) and gastric cancer cells (SNU-601) by the methanol extract from the bulb of alpine leek were 99.9% in the extracting concentration of over 200 mg/l. No significant difference in antimicrobial activity among the 3 different solvents and extract concentrations was observed, and the inhibition zones against the gram-positive and negative microorganisms were ranged from 8.23 to 10.15 mm. It was concluded that physiological activities in a human body could be improved by the intake of alpine leek as a pharmaceutical material, and that it would be useful for the prevention of health risk such as lung and gastric cancers.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.268-273
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• 2008

Because a procedure is complicated and various related parties participate in the redevelopment and reconstruction project, it can be extended to diverse disputes when the relation with the related parties is smoothly adjusted. In particular, when the dispute occurs in a phase of occupancy after the complete construction, the regional residents-centric association must give up many rights of invisible parts caused by the construction company's profit maximization because they are short of professionalism about the business. Accordingly, this study is aimed at providing the construction project manager's dispute and claim process for responding to the dispute or claim reasonably and for obtaining the client's (association) rights for the reconstruction project, and at developing the checklist for obtaining the necessary documents by each phase, when the dispute or claim is made by the association against the construction company after the completion of construction. Through this study, the association can obtain the related documents in advance and can implement the reasonable response data when the dispute or claim occurs due to it. Also, it will enable the construction manager to analyze the project costs reasonably and will reduce the estimated wastes. That is, the work efficiency is expected to be improved.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.37-45
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• 2010

WEB or Internet has given mankind an unprecedented experience in indefinite sharing of online content by original means of digitalized information, but it comes to face an empirical issue of unreasonable informational superfluity as well as a practical issue of collapsed dot.com bubble economy in 2001. Instead, a latest networking concept called 'WEB 2.0' or 'Semantic WEB' becomes embodied as a new approach to entities such as end users and content. The concept of WEB 2.0 for creating a platform on the basis of openness and collaboration has made such a technological setting that we can effectively resolve and manage unreasonable data maintenance and interface inherent in Creative Group Thinking System (CGTS), a WEB-based computer-aided idea generation system developed in 2003. Concerning decreased usability and difficulties with data maintenance due to certain issues of CGTS as a part of WEB R&D platform, such as complex display composition and inefficient data processing system, this study seeks to simplify and streamline data structure by means of AJAX and DOM as WEB2.0-based technologies, and integrate interface structure of WEB platform to focus on end users, so that it can improve interface of conventional CGTS for the purpose of realizing end user's participation through improving usability.

• Environmental and Resource Economics Review
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• v.19 no.2
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• pp.361-382
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• 2010

In 2005, the Korean government decided to postpone the introduction of competition up to 2009 in the power plant service industry. Thus, the purpose of this study is to analyze the efficiency changes and the determinants of international competitiveness of Korean power plant service industry by the comparison between before and after 2006. The sample used in the estimation of efficiency is six firms III Korean power plant service sector for the period of 2003~2008. According to the results, technical efficiency before 2006 (2003~2005) is 0.865 and that after 2005 (2006~2008) is 0.947, which implies that efficiency has been improved after the delay of introduction of competition. In addition, according to the analyses based on the diamond model of Porter using survey data, demand condition has been ranked first in the determinants of international competitiveness. The second and the third important conditions are government and input factor ones. Firm's strategy/structure/competitiveness condition is the most weak condition. Therefore, it would be necessary for firms to improve this condition for competitiveness.

• Journal of Ginseng Research
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• v.36 no.2
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• pp.161-168
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• 2012

The abnormal maturation and ossification of articular chondrocytes play a central role in the pathogenesis of osteoarthritis (OA). Inhibiting the enzymatic degradation of the extracellular matrix and maintaining the cellular phenotype are two of the major goals of interest in managing OA. Ginseng is frequently taken orally, as a crude substance, as a traditional medicine in Asian countries. Ginsenoside $Rb_1$, a major component of ginseng that contains an aglycone with a dammarane skeleton, has been reported to exhibit various biological activities, including anti-inflammatory and anti-tumor effects. However, a chondroprotective effect of ginsenoside $Rb_1$ related to OA has not yet been reported. The purpose of this study was to demonstrate the chondroprotective effect of ginsenoside $Rb_1$ on the regulation of pro-inflammatory factors and chondrogenic genes. Cultured rat articular chondrocytes were treated with 100 ${\mu}M$ ginsenoside $Rb_1$ and/or 500 ${\mu}M$ hydrogen peroxide ($H_2O_2$) and assessed for viability, reactive oxygen species production, nitric oxide (NO) release, and chondrogenic gene expression. Ginsenoside $Rb_1$ treatment resulted in reductions in the levels of pro-inflammatory cytokine and NO in $H_2O_2$-treated chondrocytes. The expression levels of chondrogenic genes, such as type II collagen and SOX9, were increased in the presence of ginsenoside $Rb_1$, whereas the expression levels of inflammatory genes related to chondrocytes, such as MMP1 and MMP13, were reduced by approximately 50%. These results suggest that ginsenoside $Rb_1$ has potential for use as a therapeutic agent in OA patients.

• Polymer(Korea)
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• v.38 no.3
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• pp.320-326
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• 2014

The effects of high shear rate processing on the thermal properties of PC/ABS blends were studied. It was executed by the high shear processing machine (NHSS2-28) at the varied conditions of screw speeds and loaded duration. After the samples were processed with NHSS2-28, the $T_gs$ were shifted from 143 to $133^{\circ}C$, and the behavior of degradation determined by TGA showed two distinct steps before high shear rate processing, while it showed a straight line after the processing. In order to provide the reasons of the properties, it was showen by SEM and UTM that the droplet sizes morphologically decreased after the processing, and the elongations decreased slightly until 1000 rpm of screw speed and then sharply decreased, according to the conditions of high shear rate processing. Therefore, it can be confirmed that $T_g,s$ of PC/ABS blends were considerably shifted under an appropriate high shear rate condition, and rapidly dropped, so that blends degraded above the condition, due to stress-induced degradation.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.510-517
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• 2013

In this study, the properties of blue inorganic nano-pigments with a spinel structure were systematically investigated. We report the preparation of a blue ceramic nano-pigment and the Co and Ni substitutional effects on the blue color. $MgAl_2O_4$ was selected as the crystalline host network for the synthesis of cobalt and nickel-based blue ceramic nano-pigments. Various compositions of $Co_xMg_{1-x}Al_2O_4$ and $Ni_xMg_{1-x}Al_2O_4$ ($0{\leq}x{\leq}1$) powders were prepared using apolymerized complex method. The obtained powder was preheated at $400^{\circ}C$ for 5 h and then calcined at $1000^{\circ}C$ for 5 h. XRD patterns of the (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ samples showed a single phase of the spinel structure in all compositions. TEM results indicated nano-sized pigments for (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ with a particle size ranging from 20 to 50 nm. The characteristics of the color tones of (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ were analyzed by CIE $L^*a^*b^*$ measurements. In addition, the thermal stability and the binding characteristics of (Co,Mg)$Al_2O_4$, (Ni,Mg)$Al_2O_4$ are discussed in terms of the TG-DSC and FT-IR results, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.76-83
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• 1992

Enterotoxigenic E. coli is one of the major causative agents of the infantile diarrhea and traveler's diarrhea. The heat-stable enterotoxin (ST) is thought to be a virulence factor in the pathogenesis of the diarrhea and to be a maker for identification of the enterotoxigenic E. coli from non pathogenic E. coli. ST producing E. coli KM-7 strain was isolated from the swine and molecular cloning of ST gene of KM-7 strain. Transformant eKT-53 $(ST^+,\;LT^-)$ was selected by infant mouse assay (IMA). The culture supernatant of eKT-53 strain was performed purification by multipled steps. The culture supernatant (crude ST) was purified by sequentially applying batch adsorption chromatography on Amberlite XAD-2 resin, ion exchange chromatography on DEAE-Sephacel anion exchanger, gel filtration chromatography on Bio-Gel P-6 and preparative polyacrylamide slab gel electrophoresis. About 113-fold purification was achieved with a yield of about 11% of crude ST and the minimum effective dose(MED) of this purified ST was about 2.8ng in IMA. Homogeneity of purified ST was demonstrated by showing a single band in analytical SDS polyacrylamide disc gel electrophoresis.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.319-333
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• 2017

The construction of long sub-sea tunnel does not provide the favorable condition for the installation of ventilation system to be used during construction due to the constrained construction space. For the ventilation system required during construction, the artificial island where ventilation shaft is located is constructed at some location along the sub-sea tunnel route, which requires a high construction cost. Therefore, it is intended, as much as possible technically, to minimize the construction of artificial island. However, this requires a longer distance between ventilation shafts, there-by causing increased air leakage at the ventilation duct connection points due to the higher fan pressure being required to deliver ventilation air. Previously the air leakage was studied as an important issue. In this study experiments were carried out to develop the improved duct connection method considering various conditions such as, tunnel length, etc. Additionally, its performance results with leakage rates are shown and compared to the "S" class leakage rate of SIA. As a result, the new duct coupling type of improved method is analyzed as applicable to such a 30 km long tunnel with the leakage rate of $1.46mm^2/m^2$, which is better performance than SIA leakage rates.

• The Korea Journal of Herbology
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• v.30 no.6
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• pp.39-46
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• 2015

Objectives : The aim of this study was to evaluate the effect of Schizonepeta Spica water extract (SS) on the OVA-induced BLAB/c mice allergic rhinitis model.Methods : Thirty two BALB/c mice were equally assigned to 4 groups; the sham group, the control group, the cetirizine hydrochloride (Cet) treatment group, and the SS treatment group. Sham group was sensitized and challenged with saline, and the other groups were sensitized and challenged with OVA. The dosage of SS was 7.6 mg /kg·day, and Cet was 10 mg/kg·day. Nasal rubbing and sneezing were measured by the behavior observation. The concentrations of IL-1β, IL-10, TNF-α and MIP-2 in the sera of allergic rhinitis model were measured by mouse cytokine/chemokine magnetic bead panel kits. Total IgE and OVA-specific IgE were measured by ELISA method. Epithelial thickness and eosinophil infiltration of nasal septum was investigated by histological examination.Results : The clinical symptoms that increased in control group were significantly reduced in SS-treated group. Serum total IgE and OVA-specific IgE in the SS-treated group were significantly reduced compared to the control group. The concentration of IL-1β, IL-10, TNF-α and MIP-2 in SS-treated group showed a significant reduction compared to the control group. The infiltration of eosinophil into nasal tissues of SS-treated group decreased markedly compared to control group, and thickness of nasal septum in nasal mucosa showed a significant reduction compared to control group.Conclusions : According to the above result, it is suggested that SS may inhibit the early and late phase of allergic rhinitis reaction.