• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.308-314
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• 2015

This paper has proposed a new boost rectifier. Adequate input current was obtained by keeping the duty ratio constant without complicated conventional control methods and the improvement of the waveform was increased. With a decrease of distortion up to 12.9[%], the scope of restriction on harmonics was set to 13.0[%]($3^{td}$ harmonics), 1.1[%]($5^{td}$ harmonics) and 0.6[%]($7^{td}$ harmonics), respectively. Because complicated methods of control are avoided, the circuit configuration is simple and practical. In particular, the said effect turned out to be highly efficient in the low boosting ratio range(boosting ratio$({\alpha})=1.25$). The feasibility of these facts has been proven both theoretically and experimentally.

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.4
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• pp.53-59
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• 1990

To suggest the fundamental data for development of the soil improvement method which increases the permeability in aquifer by jet water, laboratory tests were performed. The results obtained are as follows : 1. The diameter of the improved section was maximum value when the time of water jetting was about 4 minutes, and it was not increased according as the time of water jetting was longer than 4 minutes. 2. It appeared that 2.78 mm in diameter of the nozzle was the most optimum size in the condition of using the 1/8 HP - pump and the diameter of improved section in that case was 15.9cm 3. According to removing fine - soil particles, the original soil was improved, suitable to the purpose of improving, and then the permeability of the improved soil was 100 times of that of the original soil. 4. As the improved soil was satisfied to the design criteria of filter materials, the improvement method in this study will be useful for constructing underground collecting channels or underground collecting drainage canals.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1787-1795
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• 2015

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titers. In this study, genes encoding key proteins involved in regulation of the osmotic stress response in Streptomyces avermitilis, the industrial producer of avermectins, are investigated as targets. Disruption of either osaB_Sa, encoding a response regulator protein, or osaC_Sa, encoding a multidomain regulator of the alternative sigma factor SigB, led to increased production of both oligomycin, by up to 200%, and avermectin, by up to 37%. The mutations also conditionally affected morphological development; under osmotic stress, the mutants were unable to erect an aerial mycelium. In addition, we demonstrate the delivery of DNA into a streptomycete using biolistics. The data reveal that information on stress regulatory responses can be integrated in rational strain improvement to improve yields of bioactive secondary metabolites.

• The Journal of Industrial Distribution & Business
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• v.8 no.7
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• pp.13-20
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• 2017

Purpose - Performance appraisal has a significant influence on the development of low-carbon tourism distribution. Research design, data, and methodology - Data of this study are collected from 27 provinces (cities) of China. SBM-Malmquist model is used to measure the TFP and its dynamic changes of low-carbon tourism distribution; TOBIT model is used to discuss the factors of TFP of low-carbon tourism distribution. Results - The results show that, there are obvious differences among regional TFP of low-carbon tourism distribution, the average change tends to grow positively in general, and the western region grows fastest on average due to the improvement of technical efficiency and technical progress, while there are technical efficiency improvement but technical regresses in eastern and central regions. The economic scale, economic strength, structure of energy consumption, location quotient and government regulation have a significant positive effect on the TFP of low-carbon tourism; energy intensity, industrial structure and opening degree have a negative effect; investments in fixed assets, intensity of R&D fund and urbanization rate have no significant influence on the TFP of low-carbon tourism. Conclusions - Improving the productivity of low-carbon tourism and reducing regional differences are effective ways to develop low-carbon tourism and enhance tourism competitiveness.

• Journal of The Korean Digital Architecture Interior Association
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• v.9 no.3
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• pp.25-35
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• 2009

This study is planning improvement of welfare facilities about the hall for the aged in apartment housing. An apartment house, famous residential type in Korea, put an important value on its convenience and economical efficiency of furniture arrangement by maximizing floor space index. In this regard, leisure usage of house was not carefully considered for the aged people. To redefine the efficiency of welfare facilities, research mainly deals with analysis of realistic needs for the aged through the spot survey and interview. The main purpose of this study is to enhance the quality of welfare facilities and propose the improved welfare facilities for the aged people. Through the research, conclusions are as followed First, Facility standard and provisions of the law should be revised for considering population growth of the aged people. Second, there are 4 plan types in the hall for the aged. Contrary to our expectation, diversity of program was not found however various program planning is needed for considering its different types of plan. Third, according to regulation, space restriction is based on the number of households. Therefore, room and space standard does not depend on the number of people. From now on, in order to improve quality of welfare facilities of the aged, revision of laws and overall facility standard should be implemented in advance.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.1031-1039
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• 2011

This study was conducted to examine the influences of chitosan, sericin and collagen extract complexes (1:1:1, w/w/w, CSC-F-005) in blood glucose and lipid concentrations in the sera of streptozotocin (STZ, 55 mg/kg BW, IP injection)-induced diabetic rats (SD strain) fed on experimental diets for 5 weeks. The concentrations of blood glucose, total cholesterol, HDL-cholesterol, ratio of HDL-cholesterol concentration to total cholesterol, atherosclerotic index, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride (TG) and phospholipid (PL) in serum were effective on the metabolic regulation in diabetic rats. The activities of alkaline phosphatase (ALP) and aminotransferase (AST, ALT) in serum were lower in the extract complexes (CSC-F-005) than in the diabetic rats. The results shown above suggested that CSC-F-005 extract complexes supplementation effectively improvement of blood glucose and lipid components in the serum of STZ-induced diabetic rats.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.75
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• pp.117-136
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• 2017

Trade finance services have been played an important role in the Korea trade development history since 1960's. These days the trade environment is confronted by the 4th Industrial revolution and new trade protectionism. So we need to improve the Korea Trade Finance Services in order to improve Korea trade volume. Bank of Korea(BOK) also revised the Rule of Korea Trade Finance in 2014 and enlarged the trade fund for commercial banks where they handle the trade finance to small and medium enterprises(SME) in 2016. This article handle the current state and problems of Korea trade finance services and suggest the improvement measures as follows; First, the commercial banks, which handle trade finance fund, should improve the customs and practice of judge loan for SMEs. Second, the export volume counting rule for trade loan should harmonize between BOK's Rule and Foreign Trade Management Regulation under the Foreign Trade Act. Third, the processing trade and intermediate trade also can use the trade finance like other trade. Fourth, Trade finance should be in balance between export and import finance to defend the new protectionism. It means that the trade finance should expand to import in the certain conditions. Lastly, the related trade promotion agencies and their employees should improve their skills and abilities for handling trade finance.

• Journal of Distribution Science
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• v.12 no.9
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• pp.5-13
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• 2014

Purpose -This study is to measure the effects of retail legislations on small retailers and traditional markets. Research Design, Data, and Methodology - The authors have developed a questionnaire with five hypotheses on the basis of previous research results and six constructs: the improvement of sales volume, the number of customers, the improvement of store traffic, the increase of store staff, business expansion and retail regulation. Furthermore, the research has adopted a five-point Likert-scale technique. In order to increase research reliability as well as validity, the authors have adopted a few different research techniques such as exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Results - Although existing retail regulations might be better than nothing for now, the degree of retail constraints on large retailers should be strengthened. Furthermore, different legal methods to protect mom and pops are needed. Conclusions - In order to improve the effects of retail restrictions on large retailers, the research indicates that the central government should change a retail policy, that is, introduce new technical ways to keep mom and pops and conventional markets.

• Journal of Korean Elementary Science Education
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• v.33 no.3
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• pp.536-548
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• 2014

The purpose of this study was to develop a science gifted education program as a strategy for modulating gifted children's overexcitabilities and to examine the effect of such program on task commitment and creative personality. The results of this study were as follows. First, science gifted education program which modulated gifted children's overexcitabilities showed significant effect on the improvement of task commitment. Looking at sub domains, significant results were obtained at self-regulation. Second, science gifted education program which modulated gifted children's overexcitabilities showed significant effect on the improvement of creative personality. Looking at sub domains, significant results were obtained at the self-conviction and humors. Third, students who experienced the classes showed affirmative responses that the new teaching method was interesting and helpful. Looking at the above results, science gifted education program which modulated gifted children's overexcitabilities can be considered as effective for improving task commitment and creative personality of elementary scientific gifted students.

• Journal of the Korean Society for Library and Information Science
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• v.5
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• pp.125-151
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• 1978

It can be expected for a public library to increase the service efficiency only when librarians can be satisfied with their job. Job satisfaction is the feeling a librarian has about his salary, his work, his promotion opportunities, his co- workers, his supervisors, etc. and affects directly librarians' morale. This paper is a study on these factors that affect the professional librarians' morale in national and public libraries in Korea. The methods employed to achieve the purpose of this study are (1) to establish some tentative factors affecting librarians' morale (2) to gather and analyze the answers against them from the professional librarians working in national and public libraries in Seoul, Korea. (3) to find out the factors abstructing the librarias' morale (4) to propose the improvement plans for them. The conclusions made are as follows: (1) Delegation of rights and responsibilities. (2) Adoption of the democratic leadership. (3) The harmonious communications between managers and librarians. (4) The level of wages and allowance. (5) Revision of the librarians' promotion regulation. (6) Necessity of continuing education of librarians. (7) Satisfaction of welfare facilities. (8) Improvement of social acknowledgement for the librarians' professionalism according to the advancement the level of educational course.