• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.322-326
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• 2005

IgE-dependent histamine-releasing factor (HRF) is found extracellularly to regulate the degranulation process of histamine in mast cells and basophils and known to play a predominant role in the pathogenesis of chronic allergic disease. HRF has been also identified in the intracellular region of the cell. Previously, we reported that HRF interacts with the 3rd cytoplasmic domain of the alpha subunit of Na,K-ATPase and inhibits Na,K-ATPase activity. Since it is known that estroaen activates the sarcolemmal Na,K-ATPase, we tested whether estrogen recovers the Na,K-ATPase activity repressed by HRF. In this study, we showed that estrogen activates Na,K-ATPase repressed by HRF. RT-PCR and western blot analysis showed that estrogen doesn't reduce the expression level of HRF in HeLa cell, suggesting that this recovery effects of estrogen probably occur via indirect mechanism on HRF and Na,K-ATPase.

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.85-89
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• 2003

Many single-stage PFC(power-facto.-correction) ACHC converters suffer from the high link voltage at high input voltage and light load condition. In this paper, to suppress the link voltage, a novel high power factor high efficiency PFC AC/DC converter is proposed using the single controller which generates two gate signals so that one of them is used far gate signal of the flyback DC/DC converter switch and the other is applied to the Boost PFC stage. A 130w prototype for LCD monitor adapter with universal input $(90-265V_{rms})$ and 19.5V 6.7A output is implemented to verify the operational principles and performances. The experimental results show that the maximum link voltage stress is about 450V at 270Vac input voltage. Moreover, efficiency and power factor are over $84\%$ and 0.95, respectively, under the full load condition.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.202-206
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• 1989

A new algorithm is suggested to solve the optimal reactive power control(optimal VAR control) problem. An efficient computer program based on the latest achievements in the sparse matrix/vector techniques has been developed for this purpose. The model minimizes the real power losses in the system. The constraints include the reactive power limits of the generators, limits on the bus voltages and the operating limits of control variables- the transformer tap positions, generator terminal voltages and switchable reactive power sources. The method developed herein employs linearized sensitivity relationships of power systems to establish both the objective function for minimizing the system losses and the system performance sensitivities relating dependent and control variables. The algorithm consists of two modules, i.e. the Q-V module for reactive power-voltage control, Load flow module for computational error adjustments. In particular, the acceleration factor technique is introduced to enhance the convergence property in Q-module, The combined use of the afore-mentioned two modules ensures more effective and efficient solutions for optimal reactive power dispatch problems. Results of the application of the method to the sample system and other worst-case system demonstrated that the algorithm suggested herein is compared favourably with conventional ones in terms of computation accuracy and convergence characteristics.

• Journal of Information Technology Applications and Management
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• v.17 no.3
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• pp.121-134
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• 2010

Past studies in e-commerce loyalty were mostly focused on the effects of customer satisfaction and trust on loyalty toward online vendors. Few studies investigated the impacts of switching barriers, whilst they are widely proven to affect customer loyalty in offline commerce. Even in a handful of studies that did deal with switching barriers, their treatment of the subject remained at best superficial. This may have to do with the fact that switching costs in e-commerce could be comparatively negligible, as switching to another online vendor often involves one simple mouse click. In this study, we investigated the impact of switching barriers on loyalty under the e-commerce context. Furthermore, the extent of switching barriers which could be affected by those positive factors (most constructs were adopted from IDT) was also examined. The statistical testing results revealed that combined model which includes both the positive factors and the switching barriers explains the loyalty formation process more strongly ($R^2$ = 0.543) than each separated models ($R^2$ = 0.468 for positive factor only model, and $R^2$ = 0.365 for switching barrier only model). While only the two switching barriers such as convenience and emotional were shown to be statistically significant, we found that trust strongly influences customer's emotional barrier, let alone direct impact on loyalty, which thereby influences loyalty. The results offer insights for better understanding switching barriers in e-commerce related applications.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.11
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• pp.1744-1754
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• 2009

This study identifies the main factors of internet clothing shopping motivation and analyzes their effect on customer e-loyalty among Korean and Chinese college students. Data were collected from 300 Koreans and 300 Chinese college students. The survey was statistically analyzed through an exploratory and confirmatory factor analysis, T-test, and structural equation modeling. The factors of clothing shopping motivations were identified as merchandising characteristics, shopping convenience, value price, and hedonic pleasure. Chinese students had stronger motivations for value price and hedonic pleasure; Koreans had stronger motivations for merchandising characteristics. The structural equation model showed that the shopping motivations for merchandising characteristics, shopping convenience, and hedonic pleasure had significant effects on e-loyalty for Chinese students and the motivations for value price had significant effects on e-loyalty for Korean students. The conclusion shows a strategic direction for entering the Chinese e-market.

• Annual Conference of KIPS
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• 2015.10a
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• pp.1295-1298
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• 2015

Many firms have used e-business systems to efficiently perform their business in an e-business management environment. Firms have applied their e-business capabilities to management activities in order to raise the performance of business execution in a global market environment. In this business environment, the analysis and management for the performance of a firm's e-business execution need to efficiently build and improve its e-business capability and competitiveness. This research presents an analysis tool for a firm e-business performance to efficiently manage and improve the e-business performance in this environment. The analysis items for a firm e-business performance are developed and extracted from the major components of a general firm performance in previous studies. The generated analysis items were verified by factor analysis and reliability analysis through a pilot test. The developed twelve items were extracted from twenty items by these analyses. This study developed a 12-item tool that can totally analyze a firm e-business performance in an e-business management environment. The developed tool consists of four analysis factors and twelve items.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1063-1066
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• 2004

The rpoS gene product is a global transcriptional factor, which is involved in bacterial survival under various stress conditions. An rpoS-homologous gene was cloned from a septicemia-causing pathogenic Vibrio vulnificus. Introduction of this gene as a multicopy plasmid into various E. coli strains displayed functional complementation, for examples, increased survivability of an rpoS-defective E. coli cell and induction of known $\delta^S$-dependent, stress-responding promoters of E. coli genes.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.50-55
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• 2006

A field-resistant strain of the diamondback-moth(Plutella xylostella L.), collected from Chinese cabbage alpine farmland at Gangwon-do, Korea, was used for determination of the characteristics of resistance to chlorpyrifos using the activities of esterases and glutathione-S-transferase(GST), protein sequestration and AChE insenstivity. Although the activities of esterases extracted from resistant strain and susceptible strain were not significantly different, isozyme bands shown on the electrophoresis were different. GST activity from field resistant strain was 1.5-fold higher than that of susceptible. No differences were shown between resistant and susceptible ones in protein sequestration. The insensitivities of AChE to chlorpyrifos, however, extracted from susceptible strain was 460-fold higher than those of resistant. These results indicated that the insensitivity of AChE is the major factor for developing the resistance and activities of GST might be a minor factor.

• Communications of Mathematical Education
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• v.21 no.2 s.30
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• pp.303-320
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• 2007

The purpose of this study is to develop a tool which can be used in factor analysis of inequality on mathematics scholastic achievement. The objectives for study are as follows: First, we develop a model for 'factor analysis of inequality on mathematics scholastic achievement' transformed from Persell's 'A model for factor analysis of inequality on education'. Second, we analyze the inequality factors with the deviation index of objects on mathematics scholastic achievement that we have developed. The results of this study are as follows: We development a model for 'factor analysis of inequality on Mathematics' and inequality factors on mathematics scholastic achievement in secondary schools are private education, scholarships of parents, region, sex and school system. The factors most influenced in mathematics scholastic achievement are economic standings of household, scholarships of parents and private educations in order.

• BMB Reports
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• v.34 no.1
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• pp.80-84
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• 2001

The human papillomavirus E7 protein can form a specific complex with a retinoblastoma tumor suppressor gene product (p105-Rb) that results in the release of the E2F transcription factor, which is critical for the growth-deregulation and transforming properties of the viral E7 oncoprotein. In an attempt to apply interaction between the E7 oncoprotein and a target cellular protein Rb for an in vitro screening system for drugs against human papillomavirus infection, we primarily investigated the E7Rb binding through a pull down assay and enzyme-linked immunosorbent assay. The pull down assay showed that both glutathione S-transferase-tagged E7 and His-tagged E7 immobilized on resins specifically produced complexes with bacterially expressed Rb in a dose-dependent manner, as determined by immunoblot analyses. This result coincided with that of an enzyme-linked immunosorbent assay, which is a useful system for the mass screening of potential drugs. Taken together, this screening system (based on the interaction between E7 and Rb) can be a promising system in the development of drugs against cervical cancers caused by human papillomavirus infection.