• Journal of Environmental Science International
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• v.30 no.5
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• pp.399-406
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• 2021

The dissolution of ionized gas in dielectric barrier plasma, similar to the principle of ozone generation, is a major performance-affecting factor. In this study, the plasma gas dissolving performance of a gas mixing-circulation plasma process was evaluated using an experimental design methodology. The plasma reaction is a function of four parameters [electric current (X₁), gas flow rate (X₂), liquid flow rate (X₃) and reaction time (X₄)] modeled by the Box-Behnken design. RNO (N, N-Dimethyl-4-nitrosoaniline), an indictor of OH radical formation, was evaluated using a quadratic response surface model. The model prediction equation derived for RNO degradation was shown as a second-order polynomial. By pooling the terms with poor explanatory power as error terms and performing ANOVA, results showed high significance, with an adjusted R² value of 0.9386; this indicate that the model adequately satisfies the polynomial fit. For the RNO degradation, the measured value and the predicted values by the model equation agreed relatively well. The optimum current, gas flow rate, liquid flow rate and reaction time were obtained for the highest desirability for RNO degradation at 0.21 A, 2.65 L/min, 0.75 L/min and 6.5 min, respectively.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1813-1824
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• 2022

This paper shows the verification work of SARAX code system in the reactor core transient calculation based on the simplified EBR-II Benchmark. The SARAX code system is an analysis package developed by Xi'an Jiaotong University and aims at the advanced reactor R&D. In this work, a neutron-photon coupled power calculation model and a spatial-dependent reactivity feedback model were introduced. To verify the models used in SARAX, the EBR-II SHRT-45R test was simplified to an ULOF transient with an input flowrate change curve by fitting from reference. With the neutron-photon coupled power calculation model, SARAX gave close results in both power fraction and peak power prediction to the reference results. The location of the hottest assembly from SARAX and reference are the same and the relative power deviation of the hottest assembly is 2.6%. As for transient analysis, compared with experimental results and other calculated results, SARAX presents coincident results both in trend and absolute value. The minimum value of core net reactivity during the transient agreed well with the reported results, which ranged from -0.3$ to -0.35$. The results verify the models in SARAX, which are correct and able to simulate the in-core transient with reliable accuracy.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.3
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• pp.81-88
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• 2011

The survey was conducted with 143 companies related to textile and fashion industry in the northern region in Gyeonggi-do and the questionnaires from 126 companies were finally analyzed to get the statistic data. The questionnaire includes 19 questions and the survey was conducted from March to May 2010. In accordance with the analysis, the most urgent issue in the textile and fashion industry was the supply of manpower in the field. For the solution against the insufficiency of manpower, employment of foreigners showed the highest ratio, 47.4%. For the reasons why the number of foreign workers was increased, the insufficiency of the Korean workers showed the highest point, 62.9%. For the questions related to the conditions of regional industries, answered that the textile industry in the northern region in Gyeonggi-do would be very prospective as the future industry. There was a number of respondents who agreed that high-tech textile industry including knitting could be the industry creating the new highly added value. More than half of the respondents agreed that the textile industry contributed on strengthening the national competitiveness, boosting the development of national industry, helping the creating the jobs and dealing with the unemployment among young people. Accordingly, it was concluded that the perspective on the textile and fashion industry was positive.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5665-5669
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• 2012

Background: The vascular endothelial growth factor (VEGF) mediates vasculogenesis and angiogenesis through promoting endothelial cell growth, migration and mitosis, and has involvement in cancer pathogenesis, progression and metastasis. However, the prognostic value of VEGF in patients with prostate cancer remains controversial. Objectives: The aim of our study was to evaluate the prognostic value of VEGF in prostate cancer, and summarise the results of related research on VEGF. Methods: In accordance with an established search strategy, 11 studies with 1,529 patients were included in our meta-analysis. The correlation of VEGF-expression with overall survival and progression-free survival was evaluated by hazard ratio, either given or calculated. Results: The studies were categorized by introduction of the author, demographic data in each study, prostate cancer-relatived information, VEGF cut-off value, VEGF subtype, methods of hazard ratio (HR) estimation and its 95% confidence interval (CI). High VEGF-expression in prostate cancer is a poor prognostic factor with statistical significance for OS (HR=2.32, 95%CI: 1.40-3.24). However, high VEGF-expression showed no effect on poor PFS (HR=1.30, 95%CI: 0.88-1.72). Using Begg's, Egger's test and funnel plots, we confirmed lack of publication bias in our analysis. Conclusion: VEGF might be regarded as a prognostic maker for prostate cancer, as supported by our meta-analysis. To achieve a more definitive conclusion enabling the clinical use of VEGF in prostate cancer, we need more high-quality interventional original studies following agreed research approaches or standards.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4876-4883
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• 2013

Nowadays numbers of non-residential Korean traditional house (Han-ok) like Caf$\acute{e}$ and restaurants within the cultural property preservation area. So the purpose of this study is suggesting the necessity of governmental support about non-residential Han-ok. The research started to analyze influential factors toward them and estimate the value of non-residential Han-ok. After then it investigated what kind of value factors are important when it is agreed to the necessity of governmental support using logistic regression. According to the result, there are main 7 factors; possibilities to use Han-ok with poor residential environment, the unique appearance of Han-ok, possibilities to offer social and welfare service within local community, value to develop tourism on Han-ok, utilization of commercial area, historical deficiency and easy to access Han-ok for tourists and overseas which are an effect on decision making to sustain non-residential Han-ok.

• Computers and Concrete
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• v.20 no.5
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• pp.539-544
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• 2017

Shear walls have high stiffness and strength; however, they lack energy dissipation and repairability. In this study, an innovative slotted shear wall featuring vertical slots and steel energy dissipation connectors was developed. The ductility and energy dissipation of the shear wall were improved, while sufficient bearing capacity and structural stiffness were retained. Furthermore, the slotted shear wall does not support vertical forces, and thus it does not have to be arranged continuously along the height of the structure, leading to a much free arrangement of the shear wall. A frame-slotted shear wall structure that combines the conventional frame structure and the innovative shear wall was developed. To investigate the ductility and hysteretic behavior of the slotted shear wall, finite element models of two walls with different steel connectors were built, and pushover and quasi-static analyses were conducted. Numerical analysis results indicated that the deformability and energy dissipation were guaranteed only if the steel connectors yielded before plastic hinges in the wall limbs were formed. Finally, a modified D-value method was proposed to estimate the bearing capacity and stiffness of the slotted shear wall. In this method, the wall limbs are analogous to columns and the connectors are analogous to beams. Results obtained from the modified D-value method were compared with those obtained from the finite element analysis. It was found that the internal force and stiffness estimated with the modified D-value method agreed well with those obtained from the finite element analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.520-528
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• 1992

In order to establish the standard conditions for thermal sterilization of foods, a microcomputer based $F_o-value$ measuring system was developed upon the basis of the time-temperature profile in food. $F_o-value$ was calculated simultaneously from the time-temperature profile, and described as integrated lethality during the whole sterilization process. The accuracy of system was evaluated by the analysis of thermal diffusivity of the model solid food, Alaska pollack surimi. The $F_o-value$ could be measured precisely under the different sterilizing conditions as the varied time and temperature. The practical thermal diffusivities from various sterilizing conditions agreed well to the values predicted by some experimental equations suggested in the literatures. The differences were within the range of $\pm12\%$.

• Communications for Statistical Applications and Methods
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• v.29 no.1
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• pp.85-101
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• 2022

Derivative-linked securities (DLS) is a type of derivatives that offer an agreed return when the underlying asset price moves within a specified range by the maturity date. The underlying assets of DLS are diverse such as interest rates, exchange rates, crude oil, or gold. A German 10-year bond rate-linked DLS and a USD-GBP CMS rate-linked DLS have recently become a social issue in Korea due to a huge loss to investors. In this regard, this paper accounts for the payoff structure of these products and evaluates their prices and fair coupon rates as well as risk measures such as Value-at-Risk (VaR) and Tail-Value-at-Risk (TVaR). We would like to examine how risky these products were and whether or not their coupon rates were appropriate. We use Hull-White Model as the stochastic model for the underlying assets and Monte Carlo (MC) methods to obtain numerical results. The no-arbitrage prices of the German 10-year bond rate-linked DLS and the USD-GBP CMS rate-linked DLS at the center of the social issue turned out to be 0.9662% and 0.9355% of the original investment, respectively. Considering that Korea government bond rate for 2018 is about 2%, these values are quite low. The fair coupon rates that make the prices of DLS equal to the original investment are computed as 4.76% for the German 10-year bond rate-linked DLS and 7% for the USD-GBP CMS rate-linked DLS. Their actual coupon rates were 1.4% and 3.5%. The 95% VaR and TVaR of the loss for German 10-year bond rate-linked DLS are 37.30% and 64.45%, and those of the loss for USD-GBP CMS rate-linked DLS are 73.98% and 87.43% of the initial investment. Summing up the numerical results obtained, we could see that the DLS products of our interest were indeed quite unfavorable to individual investors.

• Transactions of the Korean hydrogen and new energy society
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• v.5 no.2
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• pp.65-71
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• 1994

Electrochemical and thermodynamic properties of $MmNi_5$ and the related alloys for nickel-metal hydride battery(Ni-MH) were studied in terms of the equilibrium hydrogen pressure. $MmNi_5$ alloy with high equilibrium hydrogen pressure(10~20atm at room temperature), which is usually difficult to charge, was substituted for Al in part. Partial substitution of Al made not only the equilibrium pressure to be reduced remarkably, but also the enthalpy change depending on the formation of metal hydride to be agreed to the value in gas phase reaction and electrochemical reaction. Besides the composition of Al which can be given the maximum discharge capacity was turned out to be between the 0.5~1.0 atoms of Al.

• Asian Journal for Public Opinion Research
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• v.3 no.1
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• pp.22-39
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• 2015

This research is a qualitative based study by using data gleaned from documentary analysis and in-depth interviews of 10 potential stakeholders were involved in the proposed high-speed train project in Thailand. Many perspectives from key informants revealed that this project would bring Thailand sustainable development in the future due to the fact that it is supposed to be an environmentally friendly mode of transportation and timesaving for passengers. Key informants who tend to have negative opinions towards the project feel apprehension due to the huge monetary investment during a time of monetary crisis. However, there was one complaint that the high-speed train is harmful to the environment surrounding the proposed area of this project. Several key informants agreed that ticket fares must be in between the cost of a bus ticket and airfare.