• Journal of Power Electronics
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• 제11권6호
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• pp.904-913
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• 2011

Previous publications regarding the design and specifications of input filters for STATCOMs usually deal with the input filter only, and seldom pay any attention to the influence of the input filters on the performance of the STATCOM systems. A detailed analysis of the influences of input filters on the stability of STATCOM systems and the corresponding design considerations are presented in this paper. Three types of input filters, L filters, LC filters, and LCL filters, are examined separately. The influences of the parameters of input filters on system stability are investigated through frequency domain methods. With direct current control taken as the major control strategy for the STATCOMs, the different situations when adopting different current detection points are covered in this analysis. A comparison between LC filters and LCL filters is also presented with optimized filter parameters. Based on the analysis, the phase margin, as one of the design considerations for the different types of input filters under different current detection schemes, is discussed. This leads to filter parameters that are different than those of the traditional design. Hardware experimental results verify the validity of the above analysis and design.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권12호
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• pp.5955-5977
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• 2018

Performance of the interpolation algorithm used in the technique of bi-dimensional empirical mode decomposition directly affects its popularization and application, so that the researchers pay more attention to the algorithm reasonable, accurate and fast. However, it has been a lack of an adaptive interpolation algorithm that is relatively satisfactory for the bi-dimensional empirical mode decomposition (BEMD) and is derived from the image characteristics. In view of this, this paper proposes an image interpolation algorithm based on the particle swarm and fractal. Its procedure includes: to analyze the given image by using the fractal brown function, to pick up the feature quantity from the image, and then to operate the adaptive image interpolation in terms of the obtained feature quantity. All parameters involved in the interpolation process are determined by using the particle swarm optimization algorithm. The presented interpolation algorithm can solve those problems of low efficiency and poor precision in the interpolation operation of bi-dimensional empirical mode decomposition and can also result in accurate and reliable bi-dimensional intrinsic modal functions with higher speed in the decomposition of the image. It lays the foundation for the further popularization and application of the bi-dimensional empirical mode decomposition algorithm.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.725-735
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• 2021

This study investigates whether the Islamic Exchange-Traded Funds (ETFs) provide significant benefit to investors relative to conventional ETFs. Six pairs of Islamic and conventional ETFs with 10-year daily price data from 2010 to 2019 have been selected from major market indices like MSCI World Index, MSCI Emerging Markets, MyETF Dow Jones Islamic Market Malaysia, MSCI South East Asia and Wahed FTSE Shariah USA Index for this study. For ETFs that are launched after 2010, the price data from launch date to 2019 are used. Our results show: First, Islamic ETFs are more likely to trade at a premium rather than at a discount, implying the investors are willing to pay a premium. Second, it is also found that Islamic ETFs have a relatively shorter period of price deviation from the benchmark, implying more price stability. Third, conventional ETFs have higher return and lower tracking errors relative to Islamic ETFs. These new findings add to the stylized facts of Islamic ETFs in the extant literature for investors, plan sponsors and regulators as to the differences between the ETFs. As policy suggestion, asset management companies can design new investment products to bridge the gap between conventional and Islamic finance.

• 한국병원경영학회지
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• 제27권1호
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• pp.20-30
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• 2022

Purposes: This study purposed to evaluate the effect of a value incentive program(VIP) on the in-hospital mortality of acute stroke. Methodology: Study period was from January 2010 to December 2018. This study included 63 hospitals for acute hemorrhagic stroke that the mortality rate per month was more than one during study period. Independent variables were time variables and hospital characteristics such as hospital type, district and bed number. Interrupted time series analysis was applied to analyze the data. Findings: In case of general hospitals, the in-hospital mortality rate per month for acute hemorrhagic stroke tends to be increased by 0.03% in overall study periods but decreased by 0.32% after the implementation of the policy. On the other hand, tertiary hospital changes are not statistically meaningful. Conclusion: This study provides evidences how the VIP was effective in improving quality of acute hemorrhagic stroke care. General hospitals showed higher policy effect compare to that of tertiary hospitals.

• International Journal of Computer Science & Network Security
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• 제22권3호
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• pp.252-258
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• 2022

Globalization, development of the information society, intensification of migration processes, and internationalization of education in recent years have significantly affected the international labour market and increased competition between professionals in various fields. Academic, research and teaching staff are currently facing rapid changes and growing demand for quality educational services. Under such conditions, educational institutions around the world pay particular attention to improving the quality of the educational process in order for their graduates to be able to compete in the international labour market. The study of the experience of teachers' professional training in advanced countries opens new opportunities for improving the system of pedagogical training in Ukraine in order to adapt it to the requirements of the European educational space. The progressive achievements of countries demonstrating a high level of teachers' professional training in accordance with international standards, having rich historical educational traditions are of considerable scientific interest; consequently, this contributes to their leadership in science and education at the regional and global levels. The purpose of the present academic paper lies in analysing the latest trends in exploring teaching experience in the European countries and performance review of passing by students and teachers of the program on studying of pedagogical practice and experience of teaching in the countries of Europe. Methodology. Analytical and empirical (questionnaire) methods were used in the research process. Results. According to the obtained results of the research, the advantages, the most common areas of educational programs and the wishes of the participants regarding the practical implementation of the experience were identified.

• 한국콘텐츠학회논문지
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• 제9권10호
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• pp.378-388
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• 2009

본 연구의 목적은 호텔 레스토랑의 식음료이외에 제공되는 물리적 환경요소에 대한 측정을 통하여 호텔레스토랑의 운영 및 경영자들에게 향후 마케팅 활동에 있어 도움을 주는데 있으며, 이러한 각 콘텐츠의 측정을 위하여 IPA분석을 실시하였다. 또한 레스토랑 이용객들에 대하여 사회교환이론을 적용하여 차이를 보고자 하였으며, 그 결과는 다음과 같다. 첫째, 호텔 레스토랑의 중요도-성과에 대한 평균비교 결과 시설의 청결성이 가장 높은 중요도와 성과를 보이고 있었다. 둘째, 사회교환이론에 따른 IPA분석결과 두 집단에서 2사분면의 '유지'분면에서 9번, 10번, 11번 문항, 3사분면의 '저순위'분면에서 1번, 3번 문항이 동일하게 포함되고 있었으며, 1사분면의 '집중'분면에서는 집단 간에 서로 다른 문항이 포함되고 있었으며, 특히 4사분면인 '과잉'분면에서는 소비비용이 없는 집단에서만 8번, 2번항목이 해당 사분면에 포함되고 있었다. 소비비용의 유무에 따라 물리적 환경에 대한 중요도와 성과가 다소 차이가 있는 것으로 나타났다. 마지막으로, 물리적환경이 행동의도에 미치는 영향에서는 유형적 환경요인만이 행동의도에 유의한 영향을 미치는 것으로 나타났다.

• 정보관리학회지
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• 제30권3호
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• pp.317-335
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• 2013

영상자료는 점차 도서관에서 중요한 장서의 일부가 되어가고 있으며 특히 공공도서관에서는 이러한 영상자료를 기반으로 다양한 문화프로그램을 운영하고 있다. 그러나 영상자료와 관련하여 저작권에서는 공연의 개념을 적용하여 공연범위를 일부 제한하고 있으며 도서관의 영상자료 사용에 대한 저작권 단체의 저작권료에 대한 요청도 논의되고 있다. 본 연구에서는 이와 같은 시점에서 도서관에서 실질적으로 영상자료를 다루고 있는 사서들이 저작권과 관련하여 인식하고 있는 문제점과 저작권료 지불에 대한 대응 의견을 조사하고자 하였다. 또한 부가적으로 영상자료의 중요성과 영상자료 관리상의 문제점도 분석하였다. 인식조사를 위한 설문은 대학 및 공공도서관을 대상으로 하여 총 292개의 응답을 받아 분석을 하였으며 2013년 5월 8일부터 6월 7일까지 총 한 달간 조사를 수행하였다. 분석결과 사서들은 영상자료 및 영상자료 서비스가 중요하다고 인지하고 있으며 판매용 영상물 상영에 대한 저작권 면책 조건에 대한 사항도 파악하고 있는 것으로 나타났다. 그러나 발행일 6개월 미만의 영상자료 사용료를 지불하는 체제에 대해서는 부정적 의견을 보이고 있어 실질적으로 저작권료를 지불하는 체제를 도입할 의사는 없는 것으로 나타났다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.226-234
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• 2008

Grain design has always been a vital and integral part of Solid Rocket Motor(SRM) design. Basing on the design objectives set by the system designer, the SRM designer has many options available for selecting the Grain configuration. Many of the available configurations may fulfill the required parameters of volumetric loading fraction, web fraction & Length to diameter ratios and produce internal ballistic results that may be in accordance to the design objectives. However, for any given set of design objectives, it is deemed necessary that best possible configuration be selected, designed and optimized. Hence optimal results of all applicable configurations are vital to be attained in order to compare and finalize the design that will produce most efficient performance. Generally the engineers pay attention and have skills on a specific grain configuration. The designing methodologies and computer codes available usually focus on single grain configuration may it be Star, Wagon Wheel or slotted tube. Hardly one can find a software or a design methodology where all such configurations can be worked on jointly and not only adequate designs be found but optimal solutions reached by applying an optimization method to find final design best suited for any design objective. In the present work design requirements have been set, grain configurations have been selected and their designing has been conducted. The internal ballistic parameters have been calculated and after finding the preliminary design solutions, the optimal solutions have been found. In doing so, software has been developed comprising of computer programs for designing the 2D grains including Star, Wagon Wheel and Slotted Tube configurations. The optimization toolbox of Matlab Fmincon has been used for getting optimal solutions. The affects of all the independent geometric design variables on the optimized solutions have been analyzed. Based on results attained from Optimization Method, an in depth comparison of Grain Configurations and analysis of performance prediction outputs have been conducted to come to conclusion as to which grain configuration is ideal for the current design requirement under study.

• 한국농촌간호학회지
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• 제18권1호
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• pp.57-71
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• 2023

Purpose: This study aims to provide primary data for policy alternatives by identifying the problem of the nursing workforce shortage. Methods: For quantitative data, 446 questionnaires were analyzed. The mean and standard deviation were used for content description. ANOVA analysis and Scheffe? test were used to compare the differences according to the hospital level. For qualitative data, 1:1 in-depth and group interviews were conducted for six participants. Results: The factors nurses prioritized when choosing a workplace were salary, commuting distance, and work-life balance. Clinical nurses cited low wages, heavy workloads, and burnout as the most considerable difficulties in performing their duties. Factors influencing nurse's turnover intention were low wages, unmanageable workload, and rotation to unwanted departments in that order. New nurses tend not to apply to small-medium-sized hospitals, experienced nurses in their 30s-40s leave hospitals due to childcare and shift work difficulties, and nurses in their 50s and older tend to move to nursing homes rather than acute hospital settings. Conclusion: In this study, wage and workload were mentioned as the most critical factors in nurses' workplace selection, job performance difficulties, and turnover intention, so it is necessary to pay attention to this aspect when improving treatment for nurses.

• 무역상무연구
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• 제49권
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• pp.139-164
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• 2011

Traditionally courts have been adopted over the years two standards of dealing with compliance of documents such as strict compliance and substantial compliance and the substantial compliance, which was somewhat less demanding than the strict compliance. However the new guidelines of ICC's international standard banking practice for the examination of documents under documentary credits set up how the UCP is to be applied in practice. The payment obligations of an issuing bank to a beneficiary are independence of the performance or the nonperformance of any contract underlying the letter of credit. However, strictly applying the principle of independence and abstraction could produce unfair results by operating unjustly enrich an unscrupulous beneficiary in case of fraud. Accordingly, when a beneficiary presents complying documents, the issuing bank is bound to honour the presentation unless the fraud rule applies on the facts of the case such as forged or material fraud. If it does, the issuing bank(issuer) needs not pay despite the complying presentation of documents by the beneficiary under the Uniform Commercial Code Article 5-109 and case law in America. However the fraud rule was not addressed in UCP 600. In conclusion, view in terms of legal principle and the court cases is variable and difficult to honour or dishonour the presentation in case of application of the independence principle and fraud rule such as the problems on burden of proof timely, possibility of granting injunction in order to protect against victim for bona fide applicant.