• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.92-101
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• 2015

As one type of power quality (PQ) disturbance sources, high-speed rail (HSR) can have major impacts on the power supply grid. Providing timely and accurate warning information for PQ problems of HSR is important for the safe and stable operation of traction power supply systems and the power supply grid. This study proposes a novel warning approach to identify PQ problems and provide warning prompts based on the monitored data of HSR. To embody the displacement and status change of monitored data, multi-features of different sliding windows are computed. To reflect the relative importance degree of these features in the overall evaluation, an analytic hierarchy process (AHP) is used to analyse the weights of multi-features. Finally, a multi-features similarity algorithm is applied to analyse the difference between monitored data and the reference data of HSR, and PQ warning results based on dynamic thresholds can be analysed to quantify its severity. Cases studies demonstrate that the proposed approach is effective and feasible, and it has now been applied to an actual PQ monitoring platform.

• The Journal of Information Systems
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• v.15 no.3
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• pp.159-174
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• 2006

Employment rate of graduating students has been one of the most important issues at universities. Recently interest on internship abroad has been increased significantly due to globalization of the society In particular, central and local governments have developed policies and encouraged university students to participate in internships abroad. However, activities and resources for internships abroad are very limited to a few organizations. This paper investigated the current status of internship in the U.S. and Korea. Then, this paper analyzed differences in demand and supply of the internship and matching mechanism of the internship between the U.S. and Korea. From the results of those analyses, this paper developed an international network model which can help effective and efficient increase in the demand and supply of the internship as well as the internship matching mechanism in Korea. This network model utilizes international NGOs in order to develop internationally cooperative environment. This model provides mechanism for (1) effectively identifying intern applicants who like to work abroad and evaluating thent (2) effectively identifying new internship positions and evaluating companies which plan to hire interns, (3) efficiently matching demand for and supply of internship by identifying appropriate candidates, (4) monitoring companies for their quality of working conditions and interns for their qualities of work This model for internship has been applied for a NGO which is International CBMC (Christian Businessman Committee International)

• Korean Journal of Human Ecology
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• v.16 no.2
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• pp.443-454
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• 2007

Survey questionnaires were conducted on housewives under 60 who had bought an apartment in Daegu. The data used in this study is collected Dalseo-Gu, Soosung-Gu and Buk-Gu by means of cluster sampling and from those chosen samples I use convenience sampling. The data were analyzed by SPSS WIN 10.0 program. The purpose of this study is to examine housing characteristics and apartment choice as a social class closely in order to improve value of apartment and to provide housing plan of apartment supply which is distinguished by a social class and moreover, to achieve efficient marketing strategy according to a recent recognition that housing is a kind of commodities. Objective and subjective measure of value are used to classify a social class. Objective measure of value includes scale apartment, a form of possession, a price of apartment, an occupation of husband, family income and academic background and subjective measure of value includes the standard of living out of people's own head. These measure of value are classified by giving consequence to each item with reference to ISC (index of status characteristics) of Wanner. There is a difference of housing characteristics and apartment choice as a social class as a consequence of this study. Therefore, this study suggests repeatedly that it should need not standardized housing supply but apartment supply of diverse demand desire because there is a difference of housing characteristics and apartment choice as a social class.

• Resources Recycling
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• v.22 no.1
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• pp.3-10
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• 2013

This general paper covers three parts of the uranium research and development. Part one covers scope of research and development of uranium ore and future prospect, supply and demand of uranium in the world market, deposit, grade and properties of Korean uranium ore and the second part covers status of previous study and supply target for yellow cake, technology of leaching, separation and preparation, procedure of the recovery of U / V from Korean black shale ore. Final part concludes the summary of the present discussion.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.4
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• pp.447-461
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• 2016

Recently, the Renewable Fuel Standard(RFS) has been commenced from July 31, 2015 in the New and Renewable Energy Act for expanding the supply of renewable energy and reduction of national GHG target in Korea. The biodiesel is only a means of implementation for the RFS, therefore the biodiesel supply expansion is important for fulfilling the RFS obligation policy. The major key points of the biodiesl supply are expanding domestic feedstocks due to the over 60% dependence on foreign feedstock and reducing the price of feedstock because of the over 70% occupation of feed stock price in the biodiesl production cost. Therefore, we estimated actual amount of potential feedstocks which are possible to use for biodiesl production in Korea and investigated technical and political improvements for expanding biodiesl. For estimating a potential feedstocks, first selected the potential biodiesl feedstocks by investigating the status of global biodiesl feedstocks and then analyzed the possible potential amount of each feedstock by surveying the generation situations, the distribution structures and the technical level.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.529-535
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• 2006

In DC tracking power supply system, ground faults are currently detected by the potential relay, 64P. Though 64P relay detects ground fault, it cannot identify the faulted region which causes long traffic delays and safety problem to passengers. A new ground fault protective relay scheme, ${\Delta}I$ ground fault protective relay, that can identify the faulted region is presented in this paper. In ${\Delta}I$ ground fault protective relaying scheme, ground fault is detected by 59, overvoltage relay, which operates ground switch installed between the negative bus and the ground. It preliminarily chooses the faulted feeder after comparing the current increases among feeders and trips the corresponding feeder breaker. After some time delay, it then recloses the breaker if it finds the preselected feeder is not the actual faulted feeder. Whether or not the preselected feeder is the actual faulted feeder is determined by checking the breaker trip status in the neighboring substation in the direction of the tripped breaker. If the corresponding breaker in the neighboring substation is also tripped, it finally judges the preselected feeder is actually a faulted feeder. Otherwise it recloses the tripped breaker. Its algorithms is presented and verified by EMTP simulation.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.10
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• pp.1041-1049
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• 2013

One of the causes of malfunction of commercial vehicle is corrosion or wear. In order to prevent corrosion and wear, lubricants have to be supplied periodically. However, the period of lubrication usually depends on operator's judgment. If the period is too short, excess lubricant will cause pollution and unnecessary expenses, where as long periodic supply of lubricant might cause wear, damage and eventual breakdown. Therefore, an automatic lubrication system with predetermined interval will reduce the excessive supply of lubricating oil and prevent wear and damage. This thesis presents an automatic lubrication system which consists of a lubricant pump and an embedded controller. An automatic lubrication operating algorithm is used to operate the lubricant pump and feedback the pressure status of the system using pressure sensors. The developed system shows an efficient periodic supply of lubricant.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.675-684
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• 2021

This paper aims to analyze factors influencing earnings of workers in Vietnam using provincial-level data from 2016 to 2018. We show the important determinants of earnings of workers of more than 15 years old including working hour, labor force, life expectancy, education, regulation measured by Provincial Competitiveness Index (PCI) and especially Industry 4.0, our major depart from literature proxies by government expenditure on science and technology, number of phone lines, and number of internet users. Working hours are a typical measurement of quantity of labor supplied. Labor force represents market size from the supply side. Life expectancy measures the health of laborers, a physical quality measure of workers. PCI stands for institutional status of the locality. Two most important factors of our interest are education, representing qualification of workers, and Industry 4.0, reflecting the new working environment of workers. By estimating a robust standard error fixed-effect model, we have evidence that all factors are significant in explaining earnings of Vietnamese workers. Education and IR4.0 play an important role in earnings of workers of Vietnam. Results also provide an estimation of Vietnam's labor supply in the context of Industry 4.0. In addition, findings contribute to explain the income discrepancy among Vietnamese provinces.

• Journal of East-Asian Urban History
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• v.3 no.1
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• pp.83-120
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• 2021

This article analyzes the publicness of early modern cities and the character of samurai residences as urban dwellers through the water supply and use of the Edo period in Japan. Firstly, in Edo, a megacity with a population of about one million, the Shogunate organized samurai residences (mainly those of feudal lords, Daimyo) into geographical organizations, and samurai residences paid for the repair of water facility and the water fee, just the same as the townspeople. Next, in Fukui (provincial castle town), samurai residence (Daimyo's vassal) organization for waterway didn't exist. The samurai residences were relieved of the burden of maintaining the waterways due to poverty. And, before the later Edo period, samurai vassals were not punished for violating the rules on water use, but they were eventually included in the punishment. The gap in feudal status between samurai and townspeople narrowed. It was a process of creating a modern urban society composed of equal dwellers. Although Edo and Fukui belonged to the same category as castle towns, the urban publicness and the position of samurai residences were different due to their dissimilar political positions as the Shogunate capital city and the Daimyo's provincial castle town.

• Journal of Home Health Care Nursing
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• v.29 no.1
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• pp.5-17
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• 2022

Purpose: This study aimed to investigate the role of hospital-based home health nursing in community care by examining the institutional progress of hospital-based home health nursing and the current status of home health nursing in Korea. Methods: Korean research data, national statistical data, government press releases, and related laws were investigated to clarify the role of hospital-based home health nursing in community care. Results: Korean visiting medical care services, including hospital-based home health nursing, was not found to be sufficient nationwide. The supply of home health nursing did not increase due to the nature of the visiting services that required transportation time, poor profitability due to insufficient insurance fees, and increase in acute beds. Conclusion: The nature of the Korean medical environment and visiting medical care makes it challenging to establish a visiting medical supply system for community care. Therefore, hospital-based home health nursing is an important infrastructure for visiting medical care, and will be a valuable resource to link discharged patients returning to the community when moving health care services. Hence, laws and institutional supplementation to expand the role of home health nursing agencies nationwide are needed along with addressing the limitations in the supply of home health nurses.