• Elastomers and Composites
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• v.51 no.2
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• pp.93-98
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• 2016

The composites of EVA/EPDM including aluminum trioxide (ATH) as a fire retardant were manufactured for the purpose of improving low temperature property and flame resistance in the rubbery materials. The ratio of EVA to EPDM didn't affect the flame resistance of the rubber composites. The addition of ATH resulted in increase of the flame resistance. In the evaluation of the cold resistance, the increasing EPDM content showed enhancement of cold resistance in the composites due to increasing low Tg EPDM. It was found out that tensile strengths of the composites showed a maximum value at 100 phr of ATH by reinforcing effect, but a minimum value at 200 phr of ATH owing to slippage between the flame retardant by the external stress. In the measurement of solvent resistance in tetrahydrofuran, the increasing ATH content yielded enhancement of solvent resistance by reducing swelling of the composite, and increasing EPDM content also resulted from increase of the solvent resistance by reduction of polarizability as well as increase of crosslink in the composites.

• Elastomers and Composites
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• v.55 no.4
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• pp.300-305
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• 2020

In recent times, polymeric foams have been popularly used in various applications. To meet the demand for these applications, polymer foams with excellent mechanical and thermal properties are required. In particular, silicone foam has gained significant attention owing to its superior thermal properties and low density. In this study, the mechanical and thermal properties of silicone foams filled with wollastonite were investigated. A maximum tensile strength of 98.3 kPa was obtained by adding 15 phr of wollastonite. The specific gravity did not exhibit a marked difference up to 10 phr, but it increased substantially above 15 phr wollastonite. Thermogravimetric analysis indicated that adding wollastonite to the silicone foam increased both the amount of residue and the thermal decomposition temperature. The morphologies of the silicone foams filled with wollastonite were observed by scanning electron microscopy.

• Elastomers and Composites
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• v.52 no.1
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• pp.22-26
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• 2017

The thermal conductivity and the adhesive properties were measured, after synthesis of thermal conductive composite which was obtained as a result of mixing alumina or graphite with acrylic adhesive synthesized by UV polymerization. The adhesive properties of the composite were evaluated measuring the peel strength at 180 degrees, the retention, and the initial tack;the thermal conductivity was estimated using laser flash analysis. As the filler contents increased, a decrease in peel strength and initial tack and an increase in retention and thermal conductivity were observed. When compared to alumina, the adhesion of graphite showed a dramatic decrease, whereas the thermal conductivity was further enhanced. It was found out that the small size of graphite increased the mechanical interlocking between the polymer and the filler, and it was easier for graphite to come into contact with other graphite in the matrix.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2429-2432
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• 2013

Background and Objectives: Yanting in Sichuan Province is one of the highest risk areas of esophageal cancer (EC) in the world. We here summarize the epidemiology of EC in Yanting using data from the national screening programme during 2006-2011. Methods: Random cluster sampling was used to select a proportion of natural villages from six towns in Yanting, and residents aged 40-69 years old were invited for screening. Participants were screened using endoscopy with iodine staining and then confirmed by histological examinations. Results: The overall detection rates of low-grade hyperplasia (LH), moderate hyperplasia (MH), high-grade hyperplasia (HH), carcinoma in situ (CIS), intramucosal carcinoma (IC) and invasive carcinoma (INC) were 5.33%, 1.28%, 0.68%, 0.15%, 0.06% and 0.29%, respectively. The detection rates of LH, MH, HH and INC increased with age, reaching the peak among those aged 60-65 years, and the prevalences of LH and MH were higher among men than among women. In addition, the detection rates of hyperplasia were much higher in mountainous than in hilly areas. Conclusions: Among the high risk population, there are a great number of people with early-stage EC or precancerous conditions who do not have presenting symptoms. In particular, the elderly, men, or those living in mountainous areas are the most vulnerable population. It is therefore important to reinforce health education and screening services among such high risk populations.

• Journal of Arbitration Studies
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• v.9 no.1
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• pp.291-322
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• 1999

The world of today faces a radical change, a new revolution, by the spread of the Internet. It is used not only for advertising but also for the exclusive rights in the field of information and communication, in add to the way of developing everyday our lives with world news, home-shopping, on-line education and so on. Actually, since the Internet Domain's Name(IDN) is unique over the world, the individual and the companies which provide information through the Internet have a keen competition to make a good IDN to memorize and organize all available information provided them. As a result, there are an increasing number of the cases where one company files suit against another for the validity of it's IDN so the policy to arbitrate and solute the cases is required. This paper is going to introduce the structure and the system of management for IDN. It will also discuss the efficient management of IDN, various case analysis of the dispute restraint and solutions, and the movement of improving the management procedure of IDN in WIPO. So we suggest to examine common disputes among IDN uses and solution methods for future problem at EC times. Therefore we have to establish the dispute solution system. Here are the two methods : one is that to establish a dispute solution organization. This organization which can conduct the new dispute solution procedure differs from the existing legislation system. The other is that to establish a dispute solution procedure i.e. the various dispute solution procedure for efficient dispute solution : council, inspection, mediation and arbitration. This procedure is conducted on-line due to features of the IDN disputes, also along with the current legislation system and the International dispute solution procedure. Because there is possibility the IDN disputes usually are connected with other countries. As there is no specific disputes solution procedure so far, we have to wait while development occurs that also striving to be coherent with and between the domestic and International solution procedure by helping to establish the International dispute solution procedure.

• Proceedings of the CALSEC Conference
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• 1998.10a
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• pp.27-43
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• 1998

Recently, most corporations in Korea need to construct new management system for overcoming economic crisis. Firstly, this paper suggests “Value Creation system”. Secondly, this paper suggests CALS as strategic substitute to achieve market efficiency, capital efficiency, personal efficiency, and operation efficiency, which are four critical factors of “Value Creation system”. Korean corporations should build new business model founded on cooperation by completing CALS system and reconstruct competitive management system by using knowledge and know-how accumulated in that process. Because most corporations keep exclusive corporate culture and little experience of cooperative relationship among businesses, strategic approaches are essential for construction of CALS. These are vertical integration, organization of CALS construction teams, concurrent development of product/process, CEO's iron will, Precise vision and strategies, and education/training of participant.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.100-105
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• 2005

The lactate dehydrogenase (EC 1.1.1.27, LDH) inhibitors were isolated from the LDH-free crude mitochondrial fraction of skeletal muscle in Syrian hamster (Mesocricetus auratus) and Korean native cattle (Bos taurus coreanae). The LDH inhibitor in skeletal muscle of M. auratus was successfully isolated by the treatment with 175 mM NaCl and ultrasonic. The LDH inhibitor in skeletal muscle of B. taurus coreanae was highly stable to heat and LDH fu isozyme was largely inhibited by the LDH inhibitor. The molecular weight of inhibitor was 22 kDa. Inhibitor played an important role in the binding of LDH with the mitochondria in tissues of skeletal muscle, kidney and liver except heart.

• BMB Reports
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• v.43 no.1
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• pp.62-68
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• 2010

Matrix Metalloproteinases (MMPs) are a family of zinc-endopeptidases which can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. 6,6'-bieckol isolated and characterized from an edible marine brown alga Ecklonia cava (EC), according to the comprehensive spectral analysis of MS and NMR data. Here the influence of 6,6'-bieckol on expressions of MMPs was examined by zymography and western blot analysis via human fibrosarcoma cell line (HT1080). It is shown that 6,6'-bieckol significantly down regulated the expressions of MMP-2 and -9 in dose-dependent manner. The influence of 6,6'-bieckol on the cell viability and cell behavior of HT1080 cells were also investigated, our dates shown that it suppressed the migration and 3D culture in HT1080 cells. Meanwhile, we explored several signal pathways which may contribute to this process, and found the suppressing of MMPs expressions in HT1080 cells might be due to the suppression of NF-${\kappa}B$ signal pathway.

• Fibers and Polymers
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• v.7 no.2
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• pp.89-94
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• 2006

Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of $298{\sim}338\;K$ was investigated. The $PEG/LiClO_4$ complexes exhibited the highest ionic conductivity of ${\sim}10^{-5}S/cm$ at $25^{\circ}C$ with the salt concentration of 1.5 M. In addition, the plasticized $PEG/LiClO_4$ complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/$LiClO_4$/(EC-PC) was $5.33{\time}10^{-4}S/cm$ at $25^{\circ}C$.

• The Journal of Korean Association of Computer Education
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• v.6 no.4
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• pp.1-10
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• 2003

There are various kinds of instructional models in the 7th national curriculum. Among them, cooperative learning is given to students in some schools. In cooperative learning, the items for assessing the team members are required in order to evaluate the individual activities for problem solving, and to know the way of objective thinking each student does. Web-based environment is good for cooperative learning. In this paper, as a previous research work of web-based cooperative learning, we propose new assessment items which are based on the outcome D belongs to the set of 11 student learning outcomes design attributed framework developed by ABET EC-2000 and the cognitive categories defined by Bloom's taxonomy. These assessment items consist of self and peer assessment. The self assessment items include the evidence of the students' thought and their own assessment. On the other hand, the peer assessment can give the students the opportunities to participate in their activities enthusiastically, to offer interactive individual feedbacks, and to develop potential through various experiences.