• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.52-59
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• 2008

This paper describes the secant method for solving the economic dispatch (ED) problem with generator constraints and transmission losses. The ED problem is an important optimization problem in the economic operation of a power system. The proposed algorithm involves selection of minimum and maximum incremental costs (lambda values) and then the evaluation of optimal lambda at required power demand is done by secant method. The proposed algorithm has been tested on a power system having 6, 15, and 40 generating units. Studies have been made on the proposed method to solve the ED problem by taking 120 and 200 units with generator constraints. Simulation results of the proposed approach were compared in terms of solution quality, convergence characteristics, and computation efficiency with conventional methods such as lambda iterative method, heuristic methods such as genetic algorithm, and meta-heuristic methods like particle swarm optimization. It is observed from different case studies that the proposed method provides qualitative solutions with less computational time compared to various methods available in the literature.

• Journal of Distribution Science
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• v.15 no.12
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• pp.31-39
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• 2017

Purpose - The purpose of the paper is to examine shipping markets exposed on severe competition after Lehman Brothers crisis in 2008, and look for some alternatives to get it over. Research design, data, and methodology - The research method to be applied is first to look into world economic situations, and then to investigate supply and demand of shipping markets, and strategic alliances as alternatives, which lead to some implication and lessons. Results - After the fierce world economic situations after Lehman Brothers crisis in U.S, it has shown that world economic output and growth is not like that of previous years. It is periods of new normal. Then, shipping has been influenced by less trade volumes and, however, shipping capacity has reached to overcapacity in supply terms. Therefore rates down is clear, and it should be needed new way of getting it over market situations. In this sense, strategic alliance is answer for overcoming difficult markets. Conclusions - From the careful look at all situations, such as world economic situation, supply and demand of shipping market, deep understanding for strategic alliances of shipping, it has reached to conclusion that strategic alliance is only answer for difficult shipping markets.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.8
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• pp.646-655
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• 2012

This study is intended to analyze the thermal performance and evaluate the applicability about non-duct type heat recovery ventilation system integrated with window. Eventually, economic analysis of the system is conducted according to building energy saving ratio of it. As results of the thermal performance, the U-factor of the window conducted on the basis of KS F 2278 appears to $1.8W/m^2K$, and the effective heat exchange efficiency of the ventilator conducted on the basis of KS B 6879 appears 49.95% for cooling, 66.89% for heating. In the applicability evaluated by TRNSYS 16, the caes of applying the heat recovery ventilator integrated with window is found to reduce the cooling or heating load by 2.9% or 13.5% than the non-ventilator case. The results of economic analysis taking a side of consumer is verified as the payback is 3 years, and the accumulated earning is 1,408,133 won in terms of '600,000 won/unit' for initial cost, 10 years for useful life of the system.

• Computational Structural Engineering : An International Journal
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• v.1 no.1
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• pp.59-69
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• 2001

This study is intended to propose a systematic approach for reliability-based assessment of life cycle cost (LCC) effectiveness and economic efficiency for cost-effective seismic upgrading of existing bridges. The LCC function is expressed as the sum of the upgrading cost and all the discounted life cycle damage costs, which is formulated as a function of the Park-Ang damage index and structural damage probability. The damage costs are expressed in terms of direct damage costs such as repair/replacement costs, human losses and property damage costs, and indirect damage costs such as road user costs and indirect regional economic losses. For dealing with a variety of uncertainties associated with earthquake loads and capacities, a simulation-based reliability approach is used. The SMART-DRAIN-2DX, which is a modified version of the well-known DRAIN-2DX, is extended by incor-porating LCC analysis based on the LCC function developed in the study. Economic efficiencies for optimal seismic upgradings of the continuous PC segmental bridges are assessed using the proposed LCC functions and benefit-cost ratio.

• Research in Community and Public Health Nursing
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• v.27 no.2
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• pp.173-182
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• 2016

Purpose: This study was conducted to survey female Vietnamese marriage immigrants' life stress and to analyze factors influencing their life stress and coping strategies. Methods: As descriptive correlation research, this study conducted a survey with 182 conveniently sampled subjects. Data were collected in June, 2015, and analyzed with descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression. Results: The subjects' life stress levels were above average, and significantly varied according to their health, and economic status. Stress coping strategies used by the subjects included assistance seeking, problem avoidance, wishful thinking, problem solving, and emotional alleviation in the order of frequency. As a result of the stepwise multiple regression, economic level, economic activity, and health status were found to be the most significant factors influencing the subjects' life stress, and these variables explained 45.1% of the variation in life stress. Conclusion: Female marriage immigrants were experiencing above-average life stress, and they were coping with it mainly in terms of assistance seeking or problem avoidance. In order to mitigate their stress, therefore, it is necessary to provide extended employment opportunities and economic activities for them so that they can cultivate their abilities in health management.

• Earthquakes and Structures
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• v.13 no.3
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• pp.323-335
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• 2017

A simplified framework for the probabilistic estimation of economic losses induced by the structural vulnerability in single-story and single-bay precast industrial buildings is presented. The simplifications introduced in the framework are oriented to the definition of an expeditious procedure adoptable by government agencies and insurance companies for preliminary risk assessment. The economic losses are evaluated considering seismic hazard, structural response, damage resulting from the structural vulnerability and only structural-vulnerability-induced e]conomic losses, i.e., structural repair or reconstruction costs (stock and flow costs) and content losses induced by structural collapse. The uncertainties associated with each step are accounted for via Monte Carlo simulations. The estimation results in a probabilistic description of the seismic risk of portal-like industrial buildings, expressed in terms of economic losses for each occurrence (i.e., seismic event) that owners (i.e., insured) and stakeholders can use to make risk management decisions. The outcome may also be useful for the definition of the insurance premiums and the evaluation of the risks and costs for the owner corresponding to the insurance industrial costs. A prototype of a precast concrete industrial building located in Mirandola, Italy, hit by the 2012 Emilia earthquake, is used as an example of the application of the procedure.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.537-547
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• 2020

This study aimed to analyze evidence of the effect of perceived ease-of-use, perceived usefulness, and perceived security on the citizen's intention to use e-Filing with information technology readiness as an intervening variable. This study used primary data collected from Civil Servants Taxpayers, Indonesian National Armed Forces, and State Police of the Republic of Indonesia in Semarang City. One hundred fifty questionnaires were distributed, and 126 were processed and analyzed. The multiple linear regression and path analysis were employed to test the hypotheses. The results indicated that perceived ease-of-use and perceived security had a positive effect on the use of e-Filing, while perceived usefulness has no effect on the use of e-Filing. In addition, readiness of information technology did not mediate the relationships among the perceived ease-of-use, perceived usefulness, and perceived security on the use of e-Filing. This study implies that Directorate General of Taxes, as a provider of e-Filing services, may improve the quality of e-Filing, especially in terms of ease and security. It is because, based on the results of this study, both aspects have been empirically proven to be able to increase intention to use e-Filing in reporting the annual notification letter.

• International Commerce and Information Review
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• v.10 no.1
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• pp.3-31
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• 2008

Northeast Asia is expected to be on economic bloc which is competed with other economic blocs such as EU, NAFTA. E-Commerce based on IT and networking results in paradigm shift in Northeast Asian Nations, that is, Korea, China, Japan, Taiwan etc. There are the similarities and differences in e-Commerce situations in these nations. The differences are the gaps in e-Commerce infrastructures such as Internet, e-Commerce solution, e-payment system and e-logistics system etc. A number of interorganizational, intraorganizational and usage level factors influences the performances of all firms using e-Commerce tools. As result of this empirical study, China records low level of e-Commerce in terms of environmental aspects, usage and performance while Korea and Japan record relatively high levels. It is also found that non-economic performance is higher than economic performance in Northeast Asian firms. The purpose of this paper contributes to resolve the digital divide in Northeast Asia and to improve e-Commerce infrastructures in Northeast Asia by estimating current e-Commerce levels of Northeast Asian countries and suggesting future development strategies of those countries through e-Commerce cooperation.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.981-988
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• 2020

Seeing the existence of MSME needs that have still not been met although this sector is undeniably important in Indonesian economy, changes in community behaviour and the intensity of the use of technology in the community, financial technology (fintech) has a lot of potentials to become a part of the solution of the problem commonly faced by MSMEs. Therefore this research needs to be done to observe the potential of fintech in integrating MSMEs in terms of the application of technology and knowledge from the community related to fintech. By using Technology Acceptance Model, this research tries to understand the determinant factors of the fintech application used by MSME. Based on the research framework and model, path analysis method used in this research. This research uses primary data gathered by the questioner, which was distributed to MSME. From the analysis conducted, we can conclude that the external factors tested in this research could have an effect on the behaviour intention through perceived usefulness in MSME practice of financial technology. Large variation in MSME educational background, busineess age and size would become a challenge in promoting fintech application, therefore this finding suggests that fintech should be promoted by highlighting what benefits can be obtained by using fintech application.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.3
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• pp.389-411
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• 2008

This paper have examined how industrial restructuring had been undertaken in response to economic crises in both Stuttgart, the hometown of the German automaker Daimler-Benz and Turin, that of the Italian automaker Fiat, in terms of changes in regional governances. Based upon this comparison, their micro dynamics have been examined that the transformation of automotive production systems from vertical integration to vertical disintegration had produced different regional development paths. It is argued that the recent transformation of auto production systems does not lead to a global convergence, but it reveals a local divergence based upon its locally embedded heritages, which is closely related to regional governances among the economic agents in question.