• International Journal of Automotive Technology
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• 제8권5호
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• pp.651-658
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• 2007

This paper presents a new type of fuzzy logic-based power control strategy for fuel cell hybrid electric vehicles designed to improve their fuel economy while maintaining the battery's state of charge. Since fuel cell systems have inherent limitations, such as a slow response time and low fuel efficiency, especially in the low power region, a battery system is typically used to assist them. To maximize the advantages of this hybrid type of configuration, a power distribution control strategy is required for the two power sources: the fuel cell system and the battery system. The required fuel cell power is procured using fuzzy rules based on the vehicle driving status and the battery status. In order to show the validity and effectiveness of the proposed power control strategy, simulations are performed using a mid-size vehicle for three types of standard drive cycle. First, the fuzzy logic-based power control strategy is shown to improves the fuel economy compared with the static power control strategy. Second, the robustness of the proposed power control strategy is verified against several variations in system parameters.

• 동력기계공학회지
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• 제18권6호
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• pp.70-76
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• 2014

Surely fuel economy(F.E.) label is needed to meet consumer's right to know. Korea has developed and adopted F.E. correction equation similar to the feeling, because consumer complain about F.E. label higher than they feel. Recently, through continuous research and development high-efficiency & performance green car like HEV, PHEV and EV are being sold. In this situation, it is needed to know whether the current equation can reflect a part of their improved technic or not. In this paper, to review current equation through test using hybrid vehicles on 5-cycle SOC, correction equation and F.E were discussed. The result show HEV didn't meet the SOC error standard on US06. Also, HEV has bigger F.E. difference between FTP-75 and 5-cycle than conventional vehicles. However, the correction equation that include HEV almost same with current one.

• The Journal of Asian Finance, Economics and Business
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• 제8권1호
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• pp.113-122
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• 2021

This study aims to investigate the effects of fiscal policy instruments on economic growth in Jordan using annual data from 1970 to 2019, by applying the VAR model (Vector Auto regression) and the Vector Error Correction Model (VECM). The study also examines the dynamic relationship among economic variables over time using the Granger casualty test, Impulse Response Function, and Variance Decomposition. The results show that not only the public expenditures have a positive effect on economic growth in Jordan, but also the tax revenues positively affect the economic growth in the short-run, and this is because of using the tax revenues to finance the government activities in Jordan. This effect becomes negative in the long run, and this is explained because the tax seems a source of distortions in the economy, The extreme taxes may cause huge distortions in the economy, and these distortions destroys the purchasing power, the aggregate demand, and supply. More governmental dependence on tax revenues is the main source of tax evasion and less efficiency. The effect of taxation will curb any prosperity in the economy. Therefore, the government should estimate the fair tax rates to generate sufficient revenues to finance the public expenditure required to enhance economic prosperity.

• The Journal of Asian Finance, Economics and Business
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• 제9권9호
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• pp.309-316
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• 2022

In 2011, the 4^th industrial revolution officially occurred and developed in most countries. The fourth industrial revolution has given organizations numerous business opportunities, enabling them to optimize their manufacturing processes, cut costs, and thereby improve their operations. The development of enterprises is a decisive factor in increasing national productivity, thereby improving economic growth and per capita income. Therefore, it is necessary to grasp the digital transformation plan and apply science and technology to domestic enterprises and improve the operational efficiency of the economy. Research on small and medium enterprises in Hanoi, Vietnam, which is considered a successful country in economic development and digital transformation and has become a middle-income economy and a highly open economy, the research results suggest that the ability to apply technology in businesses is capable of improving corporate financial performance. The choice of capital structure favoring debt has a negative effect on the financial performance of the enterprise; that is, enterprises in Vietnam should limit the choice of financing investment projects with debt, on the contrary, enterprises should choose to finance with equity. Finally, the study also discusses managerial implications for improving business performance in the context of the rapidly evolving 4.0 technology revolution.

• International Journal of Computer Science & Network Security
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• 제24권3호
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• pp.1-11
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• 2024

Payment systems are evolving, and this study examines how blockchain and AI improve online transactional security and service quality. The study examines micro and macro payment systems, compares online, and offline methods all over the world. The study also examines how blockchain and AI affect payment system security, privacy, and efficiency globally and rapidly digitizing economy. Digital payment methods are growing all over the world with high literacy and digital engagement, but they face challenges. The research highlights cybersecurity threats and the need to balance user convenience and security. It suggests blockchain and AI improve online payment services, supporting the policies for different countries. In this extensive research survey, we compare and evaluate the strengths and weaknesses of various payment systems, their practicality, and their robustness. This study also examines how technological innovations and payment systems interact to reveal how blockchain and AI could transform the financial sector. It seeks to understand how technology-enhancing service quality can boost customer satisfaction and financial stability in the digital age. The findings should help policymakers, financial institutions, and technology developers optimize online payment systems for a more secure and efficient digital economy.

• 한국체육학회지인문사회과학편
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• 제57권6호
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• pp.123-134
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• 2018

본 연구는 2018년부터 문체부에서 주관하는 스포츠산업 선도기업 육성사업의 경제성 분석을 목적으로 한다. 스포츠산업 선도기업은 스포츠산업에서 일정 규모의 매출액을 보유하고 글로벌 성장 가능성을 갖춘 스포츠산업체를 의미한다. 지원 분야는 사업고도화, 해외판로개척 및 해외 홍보마케팅 통합지원이다. 연구방법은 정책지원에 따른 공급 및 수요함수 모형개발과 산업연관분석이며 기업 매출액 규모에 따라 시나리오를 설정하여 결과를 도출하였다. 경제성 추정 분야는 기업의 매출액 변화와 국민경제 파급효과이다. 연구결과는 다음과 같다. 첫째, 스포츠산업 선도기업 육성정책 실행에 따른 기업의 매출액 증가율은 3.74%에서 5.19%에 이르는 것으로 추정되었다. 둘째, 매출액 증가는 기업 매출액 규모에 따라 최소 15.73억 원에서 최대 40.81억 원에 이르는 것으로 나타났다. 셋째, 국민경제 파급효과 중 생산유발액의 경우 최소 360억 원에서 934억 원에 이르는 것으로 추정되었다. 넷째, 국민경제 파급효과 중 부가가치 유발액의 경우 최소 113억 원에서 최대 292억 원 규모로 추산되었다.

• The Journal of Asian Finance, Economics and Business
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• 제7권12호
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• pp.555-564
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• 2020

The purpose of this study is to analyze the efficiency of research institutes of futures companies, and to promote the development of futures market and real economy. This study employs DEA-solver software to conduct super-efficiency data envelopment analysis (SE-DEA), and also selects 40 representative futures research institutes in China as decision-making units (DMUs). For data of input and output indicators, we collect from the China Futures Association, Futures Daily, Hexun.com and Webstock.com respectively, and the time duration is the 103 trading days between from October 2019 to February 2020. Then the indicator for the strategy accuracy rate is calculated separately by analyzing the strategies published by each DMUs in public media. In conclusions, most institutes have excessive investment in human resources, and also have insufficient strategy accuracy rate and insufficient published research reports. The findings of this study suggest that Chinese futures companies need to improve the efficiency of research institutes, and better meet the demand of the financial market. In fact, the analysis of the efficiency of the futures company research institute has not been found in the literature worldwide, Application of DEA model in efficiency analysis of securities and futures research institutions and establishment of indicators are the innovations of this paper.

• Asia pacific journal of information systems
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• 제12권3호
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• pp.1-20
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• 2002

For the last decade, some leading groups of corporations in Korea have integrated and managed their Information Systems(IS) functions. Each group established a separate System Management(SM) company to manage the IS and tried to get a synergy effect from the integration. These attempts, however, were not initiated by any one company. Rather they were group efforts. Moreover, the previous measuring tools evaluated IS with the scope of technical performance or quantitative user satisfaction using an absolute scale. Obscure criteria were used in an attempt to present improvements in IS function which were qualitatively weak. This study evaluates whether integration has been efficient and successful. For this purpose, we evaluate the performance efficiency of IS functions with Data Envelopment Analysis(DEA) methodology. In comparison with prior methods, DEA presents the rate of relative efficiency, the efficiency frontier for improving inefficiency, the degree of improvement(slack), and the guideline to construct any benchmark(reference set). For our DEA evaluation, this study selected a leading group of 23 companies in Korea. Our experimental results are as follows. First, efficiency was rated low on average. It also demonstrates that the motivation of performance efficiency of IS functions is deficient. Second, the result of the test to find the existence of economy of scale and scope shows that the growth of an organization and industrial characteristics do not affect IS performance efficiency from the perspective of user satisfaction. Finally, the comparison with other evaluation approaches informs us that DEA can be a complementary evaluation method which supports other measuring tools.

• KDI Journal of Economic Policy
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• 제39권4호
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• pp.25-50
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• 2017

Whereas a large variety of previous studies show mixed results regarding the relationship between public investment and economic outcome, several studies have been conducted on related issues in Korea. The present study deals with the effect of public investment in Korea on economic growth and productivity. Using administrative data, it exploits three different methodologies: the total factor productivity approach, production function approach, and stochastic frontier production function approach. The results of this study show that public investment has a statistically significant effect on economic growth. However, it contributes little to enhance productivity. It is explained that there exists inefficiency of production in the Korean economy. These findings indicate that public investment has played a central role in the direct input factor and not in indirect role in Korea. Thus, it is necessary for public investment policies to concentrate on enhancing the efficiency of the Korean economy.

• 디지털융복합연구
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• 제7권2호
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• pp.35-41
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• 2009

The information technology, in the digital economy era, does a very important role not only for the country's administrative management innovation but also for the business and for the everyday life. Specifically, the e-business for the company or organization is defined as "using the Internet and IT, rescheduling of business process management activities to increase productivity and efficiency and to create new business opportunities." Thanks to the Korea's recent efforts, overall level of informatization and digitalization is able to receive high praise. But the e-business readiness (e-readiness) level is still expected a lot of room for improvement. In this paper, I try to analyze the informatization level of Korea's by the EIU's e-business readiness index and IT industry competitiveness index, to prepare a full-scale e-business era of global competitiveness through any preparation that could do to improve the situation from the analysis of statistical data.