• Elastomers and Composites
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• v.39 no.4
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• pp.281-285
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• 2004

In this paper, the simple way to evaluate the value of the activation energy for the overall rate of free radical polymerization by using DSC thermograms was studied using free radical polymerization or butylacrylate as a model. Activation ehergies were determined at heating rates of 1, 2, 5, and $10^{\circ}C/min$ by applying the multiple scanning-rate methods of Kissinger, Osawa, and half-width methods as well as the single rate method of Barrett. The value of the overall activation energy measured was closely matched with the values calculated from individual data. This work also demonstrated that the use of the isoconversional method was a simple and effective way to estimate the activation energy for the overall free radical polymerization.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.209-215
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• 1980

Proteases from papaya latex were partially purified by ammonium sulfate precipitation and separated into two fractions (Fraction I and II ) by carboxymethyl cellelose column chromatography. Each fraction, mixture of the two fractions, and crude extract of the papaya latex at pH 7.0 were inactivated at the range of $60{\sim}90^{\circ}C$ and thermal properties of the enzymes were investigated. In the thermal inactivation of fraction I, the enthalpy of activation was 89.5 kJ/mol; the entropy of activation, -44.0 J/mol K; the free energy of activation, 104.6 kJ/mol; z-value, $25^{\circ}C$. For fraction II, the enthalpy of activation was 96.5 kJ,/mol; the entropy of activation, -22.0 J/mol K; the free energy of activation, 104.0 kJ/mol; z-value, $23^{\circ}C$. For the mixture of fraction I and II, the enthalpy of activation was 90.9 kJ/mol; the entropy of activation, -38.8 J/mol·K; the free energy of activation, 104.2 kJ/mol; z-value, $24.6^{\circ}C$. For crude extract, the enthalpy of activation was 113.8 kJ/mol; the entropy of activation, 22.0 J/mol·K; the free energy of activation, 106.2 kJ/mol; z-value, $23.2^{\circ}C$. It was indicated that the fraction I was more heat-stable than the fraction II and this suggested that the thermal stability of the proteases in papaya latex is probably due to the fraction I.

• BMB Reports
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• v.30 no.3
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• pp.182-187
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• 1997

The NADPH oxidase of phagocytes catalyzes the reduction of oxygen to $O_2^-$ at the expense of NADPH. The enzyme is dormant in resting neutrophils and becomes activated on stimulation. During activation, $p47^{phox}\;(\underline{ph}agocyte\;\underline{ox}idase\;factor)$, a cytosolic oxidase subunit, becomes extensively phosphorylated at a number of serines located between S303-S379. Oxidase activation can also be achieved by the addition of phosphorylated recombinant $p47^{phox}$ by protein kinase C in the cell-free system in the presence of $GTP{\gamma}S$. The cell-free activation is inhibited by wortmannin and LY294002. specific inhibitors of phosphatidylinositol 3kinase (PI 3-kinasel) These results indicate that PI 3-kinase may playa pivotal role in the activation of NADPH oxidase.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.28
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• pp.63-88
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• 2005

Korean government is planning to develop the airport and its surrounding area into a Northeast Hub of Asia. In accordance with the Free Trade Zones Act, Incheon International Airport Corporation is in charge of developing the free trade zone which will be located adjacent to the airport cargo terminals. The free trade zone plays an important part for the promotion of international logistics. So the purpose of this paper is to make research on the activation measures of the airport free trade zone for the building of a hub of international logistics. As for the research, this paper reviews the current regulations of the Free Trade Zones Act. Also this paper analyzes recent plans and reports on the free trade zone by Incheon International Airport Corporation and Korean government authorities. As the results of this paper, it will contribute to the activation of the airport free trade zone, and to building Incheon International Airport into the logistics hub of Northeast Asia, and to the inducement of foreigner's investment in the free trade zone.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.569-576
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• 2003

Although the Free Trade Zone(FTZ) are actually competing with various strategies, the definition and structural understanding of activation strategies are not known very much Therefore this study has launched from this fact, and has the objective of obtaining the structural model for activation strategies in Gunsan FTZ, and understanding the components of activation in these region The process began by abstracting the components that composed the success factors in FTZ through recent research, and grouping it by the most core components. Also, by using the FSM(Fuzzy Structural Modeling) method to understand the structure of the grouped components, and the structural model for activation of FTZ was able to obtain as the result. When analyzing the obtained structural model, expansion of tax reduction, flexibility of law systems and good business environment came out to be the most important component groups, and especially flexibility of law systems and good business environment were the most effective component that effected all the other components overall.

• BMB Reports
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• v.32 no.1
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• pp.60-66
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• 1999

Matrix metalloproteinase-2 (MMP-2; 72-kDa gelatinase; 72-kDa type IV collagenase; gelatinase A) plays an important role in normal physiological processes and in many pathologic processes such as arthritis and metastasis of cancer. Tissue inhibitor of metalloproteinases-2 (TIMP-2) binds to proMMP-2 or mature MMP-2 at a 1:1 ratio and inhibits the catalytic activity of MMP-2. We demonstrated that the baculovirus/insect cell system does not have TIMP-2 activity. The human proMMP-2 free of TIMP-2 was expressed in the expression system and purified by one-step affinity chromatography using gelatin-Sepharose. The free proMMP-2 was autoactivated to the mature MMP-2 and autodegraded into smaller molecular weight forms in the absence of external activator. The activation and autodegradation of the proMMP-2 was much more rapid in the presence of 4-aminophenylmercuric acetate (APMA). Addition of TIMP-2 inhibits both APMA-induced activation and autodegradation of the free proMMP-2. However, an increasing concentration of TIMP-2 more readily inhibited activation of the free proMMP-2 than autodegradation. These results demonstrate that TIMP-2 plays roles in inhibition of both activation and autodegradation of the free proMMP-2 in addition to inhibition of the catalytic activity of MMP-2.

• The Journal of Bigdata
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• v.5 no.1
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• pp.65-75
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• 2020

This study intends to propose a policy plan for the activation of the Busan Blockchain Regulation-Free Zone, which is selected by the government's comprehensive negative regulation policy. Unlike Europe and the United States, Korea is based on a positive regulation and aims at suppression, not activation. The Korean government proposed a transition to "comprehensive negative regulation" as a groundbreaking regulatory innovation policy to solve the problems of positive regulation. For this implementation plan, seven regulation-free zones were selected. Busan was selected as the Blockchain Regulation-Free Zone, and secured an opportunity to revitalize the stagnant regional economy based on the blockchain. This study is a policy study for the activation of the Busan Blockchain Regulation-Free Zone, and aimed to propose a method to create an industrial ecosystem with the discovery of a Busan-specific Blockchain service that can be commercialized in the Regulation-Free Zone.

• Journal of Biomedical Engineering Research
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• v.36 no.5
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• pp.198-203
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• 2015

The purpose of the study is to examine the effects of pacemaker location on cardiac pumping efficacy theoretically. We used a three-dimensional finite element cardiac electromechanical model of canine ventricles with models of the circulatory system. Electrical activation time for normal sinus rhythm and artificial pacing in apex, left ventricular free wall, and right ventricular free wall were obtained from electrophysiological model. We applied the electrical activation time maps to the mechanical contraction model and obtained cardiac mechanical responses such as myocardial contractile ATP consumption, stroke work, stroke volume, ejection fraction, and etc. Among three artificial pacing methods, left ventricle pacing showed best performance in ventricular pumping efficacy.

• Bulletin of the Korean Chemical Society
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• v.12 no.5
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• pp.468-473
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• 1991

Viscoelastic properties of PET filament fibers on stress relaxation were investigated in the solvents of $H_2$O, 0.05% NaOH and 50% DMF using an Instron (UTM4-100 Tensilon) with solvent chamber. The theoretical stress relaxation equation derived by applying the Ree-Eyring's hyperbolic sine law to dashpot of three element non-Newtonian model was applied to the experimental stress relaxation curves, and the model parameters $G_1,G_2$, ${\alpha}$ and ${\beta}$ were obtained. By analyzing temperature dependency of the relaxation time, the values of activation entropy, activation enthalpy and activation free energy for flow in PET filament fiber were evaluated, the activation free energy being about 25.7 kcal/mol. The self diffusion coefficient and hole distance were obtained from parameters ${\alpha}$, ${\beta}$ and crystallite size in order to study the self diffusion and the orientation of crystallites in amorphous region and the effect of solvent.

• The Korea Journal of Herbology
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• v.25 no.3
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• pp.81-90
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• 2010

Objectives : The present study purposed to compare the effects of Melandrii Herba and Vaccariae Semen, which are used as Wang-Bul-Yu-Haeng(王不留行) with vasodilatory effect in Korea and China, respectively, on hyperlipidemia. Methods : We applied the water extract of Melandrii Herba and Vaccariae Semen to rats with hyperlipidemia induced by high-cholesterol diet and high-fructose diet and evaluated their effects. Results : While Vaccariae Semen had significant effect on the reduction of the levels of total cholesterol, LDL-cholesterol, free cholesterol, and the activation of ALT, the application of Melandrii Herba had no significant effect on the levels of total cholesterol, LDL-cholesterol, free cholesterol, neutral fat, and free fatty acid, and the activation of AST. For the rats with hypertriglyceridemia, Vaccariae Semen reduced the levels of neutral fat and total cholesterol, but did not significantly reduce the level of free fatty acid and the activation of AST and ALT. The application of Melandrii Herba did not have any significant effect on the levels of neutral fat, total cholesterol, and free fatty acid, and the activation of AST and ALT, but it increased the level of HDL cholesterol. Conclusion : Vaccariae Semen showed a possibility as a remedy for hyperlipidemia, but Melandrii Herba did not show any significant effect. Thus, based on such a difference in remedial effect between Melandrii Herba and Vaccariae Semen, they need to be distinguished in clinical application.