• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.5
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• pp.258-264
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• 2006

This paper presents an integrative control scheme for series-type active power filters combined with shunt passive filters not only to compensate for the source voltage unbalance and current harmonics but also to correct the power factor. To reduce the power capacity of the active filters, passive filters are connected in parallel. Diode rectifiers are replaced by the PWM converters in order to feed the real power back to the source. Power factor control is performed by changing the phase of the load voltage so that the phase of the source current coincides with that of the source voltage. The resultant voltage reference is the addition of the voltage component compensating for the source voltage unbalance and harmonic currents and the voltage component correcting the power factor. The validity of the proposed algorithm has been verified by experimental results.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.6
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• pp.77-84
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• 1997

buck type converter doesn't appear when an input voltag eis lower than an output voltage. This is the main reason the buck converter has not been used for high power factor converters. In this paper, soft switching high power factor buck converter is proposed. This converter is composed of diode rectifier, input capacitor can be small enough to filter input current, buck converter with loss less snubber circuit. Converter is operated in discontinous conduction mode, turn on of the switching device is a zero current switching (ZCS) and high powr factor input is obtianed. In addition, zero voltage switching (ZVS) at trun off is achieved and switching loss is reduced using loss less snubber circuit. The capacitor used in the snubber circuit raised output voltage. Therefore, proposed converter has higher output voltage and higher efficiency than conventional buck type converter at same duty factor in discontinous conduction mode operation. High power factro, efficiency, soft switching operation of proposed converter is veified by simulation using Pspice and experimental results.

• Language and Information
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• v.19 no.1
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• pp.1-18
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• 2015

Korean marks case for subjects and objects, but it is well known that case-markers can be dropped in certain contexts. Kwon and Zribi-Hertz (2008) establishes the phenomenon of Korean case drop on a single factor of f(ocus)-structure visibility and claims that both subject and object case drop can fall under a single linguistic generalization of information structure. However, the supporting data is not empirically substantiated and the tenability of the f-structure analysis is still under question. In this paper, an experiment was conducted to show that the specific claims of Kwon and Zribi-Hertz's analysis that places exclusive importance on information structure cannot be adequately supported by empirical evidence. In addition, the present study examines H. Lee's (2006a, 2006c) multi-factor analysis of object case drop and investigates whether this approach can subsume both subject and object case drop under a unified analysis. The present findings indicate that the multi-factor analysis that involves the interaction of independent factors (Focus, Animacy, and Definiteness) is also compatible with subject case drop, and that judgments on case drop are not categorical but form gradient statistical preferences.

• Biomedical Science Letters
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• v.20 no.2
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• pp.56-61
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• 2014

This study attempted to confirm the antioxidative potential of luteolin against tert-butyl hydroperoxide (t-BHP) induced oxidative damage and to investigate its molecular mechanism related to glutathione (GSH)-dependent enzymes in HepG2 cells. Treatment with luteolin resulted in attenuation of t-BHP induced generation of reactive oxygen species (ROS) and oxidative stress-mediated cell death. In addition, accelerated expression of GSH-dependent antioxidative enzymes, glutathione peroxidase (GPx) and glutathione reductase (GR), and heme oxygenase (HO)-1, as well as strengthened GSH content was induced by treatment with luteolin, which was in accordance with increased nuclear translocation of nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), a transcription factor for phase 2 enzymes, in a dose-dependent manner. These results suggest that the cytoprotective potential of luteolin against oxidative damage can be attributed to fortified GSH-mediated antioxidative pathway and HO-1 expression through regulation of Nrf2 in HepG2 cells.

• Journal of Information Technology Services
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• v.13 no.3
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• pp.275-298
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• 2014

The purpose of this study is to verify the difference between the importance level and the satisfaction level of each purchase decision factor of smart phone. Through review of literatures about purchase decision factors, we have derived about attributes of 6 factors. T-test, importance performance analysis (IPA), and regression analysis were conducted to identify priorities among the details of the importance and satisfaction and to analyze the effect relationship between satisfaction of each factor and overall satisfaction. Looking at a few high-priority order, battery capacity, memory capacity, fast and accurate repair, the adequacy of the repair cost, and processor in the top five factors were shown to be an important factor when purchasing smart phones. The results of this study can provide the marketing strategies for smart phone suppliers. In addition, these results imply what factors of smart phones should be more considered before launching into chinese smart phone market.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.113-125
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• 1998

The amount of mercury emitted from an incinerator depends on the properties of waste, combustion condition, and control devices. Mercury concentration in air proportionates to the increase of incinerator installation. The purpose of this study is to provide a method for determination of mercury emission factor which can predict the amount of mercury emitted from each incinerator specifically. Case study was performed for N municipal waste incinerator. Based on the method presented in this paper, we obtained mercury emission factor as 1.85~1.95 g Hg/t at N Municipal Waste Incinerator and this result was regarded as reasonable when compared with existing mercury emission factor in reference cases. Fluorescent lamps turned out to be the most important source(44.4%) of mercury in municipal waste and its amount will tend to increase, while batteries become less significant. In addition, medical waste is one of the major source of mercury.

• Gut and Liver
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• v.12 no.6
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• pp.623-632
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• 2018

Intestinal Behçet's disease is a rare, immune-mediated chronic intestinal inflammatory disease; therefore, clinical trials to optimize the management and treatment of patients are scarce. Moreover, intestinal Behçet's disease is difficult to treat and often requires surgery because of the failure of conventional medical treatment. Administration of anti-tumor necrosis factor-${\alpha}$, a potential therapeutic strategy, is currently under active clinical investigation, and evidence of its effectiveness for both intestinal Behçet's disease and inflammatory bowel diseases has been accumulating. Here, we review updated data on current experiences and outcomes after the administration of anti-tumor necrosis factor-${\alpha}$ for the treatment of intestinal Behçet's disease. In addition to infliximab and adalimumab, which are the most commonly used agents, we describe agents such as golimumab, etanercept, and certolizumab pegol, which have recently been shown to be effective in refractory intestinal Behçet's disease. This review also discusses safety issues associated with anti-tumor necrosis factor-${\alpha}$, including vulnerability to infections and malignancy.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.81-92
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• 2014

This study suggests 5 evaluation criteria (safety and technology, environmental impact, economic feasibility, social factors, and institutional factors) and 24 evaluation indicators for a NFC (nuclear fuel cycle) derived using factor analysis. To do so, a survey using 1 on 1 interview was given to nuclear energy experts and local residents who live near nuclear power plants. In addition, by conducting a factor analysis, homogeneous evaluation indicators were grouped with the same evaluation criteria, and unnecessary evaluation criteria and evaluation indicators were dropped out. As a result of analyzing the weight of evaluation criteria with the sample of nuclear power experts and the general public, both sides recognized safety as the most important evaluation criterion, and the social factors such as public acceptance appeared to be ranked as more important evaluation criteria by the nuclear energy experts than the general public.

• Journal of the Korean Society of Costume
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• v.31
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• pp.203-214
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• 1997

The neck is the human body is closely con-nected with the life and properties of keeping warm as one of the opening part in clothes. In ancient times it was put on necklace for the protection of neck and in Rome it was worn muffler called focale for the protection of neck throat. in addition cravat directly originated in necktie today was primarily worn for the protection of soldier's neck and has been turned into decorative purpose until today. As the ornament is developed to vari-ous kinds of form the neck decoration is changed and grown again and again. Therefore this thesis studies history of the neckwear and various the symbolic factor. The first factor is the social. The neckwear shows the social position class and status and does social mutual interaction as conversation starters. The second factor is the mental It express individuality fondness attitude and is felt to be indignity by being forced to be worn. The third factor is the political. it shows political tendency by indicating the royal sign or part's sign in necktie like the French royal-ist's green muffler The forth factor is the man's sexual. I expresses wearing stock being brave symbol-izing independence. The sixth factor is the traditional. It is worn with appearing traditionand custom and one of cultural movements. The seventh factor is the ideological. It symbolizes the freedom of suffragettes and emancipation of woman. The social factor is the most extensive among them. The neckwear is various in the way of expression like its kinds and is generalized, It functions as a independent part of clothes.

• The Mathematical Education
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• v.45 no.3 s.114
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• pp.251-262
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• 2006

This study investigates 628 high school students' math dislike tendencies by their math achievement levels. The findings show that, firstly, as the sample students' math achievement level decreases, the number of dislike factors increase. Secondly, students' math dislike factors are differentiated by their math achievement levels. Math high achievers show high math disliking tendency by teacher factor. Middle achievers show high math disliking tendency by complex application and relation factors. Low achievers show high math disliking tendency by comprehension factor. Finally the math disliking factors affecting the level of math achievement are influenced by schools and grades that students' attend. While math disliking factors such as comprehension factor, teacher factor, affection factor are generally present among sample schools, exceptionally JS high school students(high achieving students) are only affected by mentality factor. In addition, mentality factor affects the second grade students only. The implications of the study argue that students' math disliking tendencies could be systematically reduced by paying attention to such dependent variables students' achievement levels, grade, school characteristics, and independent variables including teacher, application, mentality, comprehension, and affection.