• Progress in Superconductivity and Cryogenics
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• v.8 no.1
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• pp.45-48
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• 2006

In the response to the demand for electrical energy , much effort was given to develop and commercialize high temperature superconducting (HTS) power equipments has been made around the world. Especially, HTS transformer is one of the most promising devices . but the cryogenic insulation technology should be established during development Hence many types of dielectric tests should be carried out to understand the dielectric phenomena at cryogenic temperature and to gather various dielectric data. Among the many types dielectric tests . the characteristic of barrier effect were conducted using simulated electrode after analysing the insulating configuration of HTS transformer main winding. The influence of a barrier on the dielectric strength was measured according to the position of the harriet the number of the barrier and thickness or the barrier. It was shown that the effectiveness . namely the ratio of the breakdown voltage in presence of barrier to the voltage without barrier, is highest when the barrier is placed at the needle electrode side. On the contrary, in the case of having the barrier between the electrodes, the harrier was placed between the electrodes the characteristic was even improved slightly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.61-64
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• 2003

In the response to an increasing demand for electrical energy, much effort aimed to develop and commercialise HTS power equipments is going on around the world. For the development, it is necessary to establish the dielectric technology in $LN_2$. Hence many types of dielectric tests should be carried out to understand the dielectric phenomena at cryogenic temperature and to gather various dielectric data. Among the many types dielectric tests, the barrier effect were conducted with the simulated electrode after analysing the insulating configuration of the pancake coil type HTS transformer. The influence of a barrier on the dielectric strength was measured according to the size and the position of the barrier. It was shown that the effectiveness, the ratio of the breakdown voltage in presence of barrier to the voltage without barrier, is highest when the barrier is placed at the needle electrode side. And the barrier effect was not depend on the electrode array. The life time to breakdown with decreasing the applied voltage was increased remarkably having wide error band but the shape parameter in Weibull distribution was almost constant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5564-5577
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• 2014

This study examined how the differences in household characteristics influence consumer expenditure patterns. The Price-Scaling AIDS model with household income and expenditure survey data were used for the analysis. The results showed that the income elasticity of the service items is greater than non-service items, indicating an increase in higher demand of service items with the same increase in household income. The household expenditure patterns vary according to the commodities, holding age and income level. The so-called traditional pattern, which emphasizes spending for non-service items, changed to the one with a higher expenditure ratio for service items. Such a change in household expenditure patterns naturally derives the expansion of the relevant service market; hence, the growth of the related service industry. This highlights the need to formulate an appropriate response from the supply side that deals with the changes in the service market.

• Elastomers and Composites
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• v.44 no.2
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• pp.122-133
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• 2009

Rubbers, such as natural rubber, polybutadiene, styrene-butadiene rubber, nitrile-butadiene rubber, chlorinated rubber and EPDM, have been continuously improved in response to a heavy demand and a new property requirement from industry. One of the best ways to realize the improvement is the modification of rubbers through chemical reactions, which produce materials with novel properties. In this review, chemical modification reactions of rubbers that contain carbon-carbon double bond units either in their main backbone or as a side group were briefly summarized. The chemical reactions introduce functional groups or functional polymer chains to polymer backbone, which transform a classical rubber to a highly functional material. Especially, we focused on a controlled/"living" radical polymerization techniques, with which a revolutionary broadening of the spectrum of the materials with well defined molecular weight, molecular weight distribution, chain end-functionality and architectures become possible.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.59-71
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• 2014

At present, Korean one-person households have been continuously increased in spite of the reduction of total population. The increasement of one-person household has become a social and institutional issue. It is necessary to response socially and economically to not only changes of housing demand but also the disadvantaged classes such as the socially weak and single elderly household from the national level. In this respect, this research examined the spatial distribution (such as the increasing area, high-density area, and majority area) of one-person household with census data in the city of Busan. The clusters of one-person households were selected by focusing on the spatial distributions by time series changes of 2000, 2005, and 2010 and considering their housing characteristics. In terms of policy efficiency, the clusters of one-person households to be supported by priority were derived by analyzing the census data from 6066 output areas in the city of Busan. As a result, lots of one-person households of juniors were distributed around the university town, office facility, and station service area. Lots of one-person households at middle-aged class were distributed in Busan's original downtown and mountain-side road. Generalizing these characteristics, cluster analysis was conducted. As a result, one-person household dense area in Busan could be classified into four types. This research should be utilized as a counterplan for increasing the housing demand of one-person household or basic data for supporting small housing supply policies in the future.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.81-89
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• 2002

The Battery Energy Storage System (BESS) has lots of advantages such as load leveling, quick response emergency power (spinning reserve), frequency and voltage control, improvement of reliability, and deferred generation and transmission construction. However, it is very critical that economic feasibility requires justification from the customer side of meter to promoting the dissemination of BESS in nation widely. In this paper, we proposed the economic assessment model of customer owned BESS which is complemented and improved the existing model. The proposed model is applied to the typical customer types, i.e. light industrial, commercial, and residential, which are taken from the statistical analysis on the load profile survey of Korea Electric Power COmpany (KEPCO). The economic viability performed for each customer load type to justifying their economic feasibility of BESS installation from the economic measures such as payback period, Net Present Worth (NPW), Rate Of Return (ROR). The results show that the BESS has economic benefits to the specific customer type, i.e. residential customer. Therefore, the government and the energy agency should be committing the support program, such as tax incentive, financial support, to disseminate the BESS nation widely. The results of this paper are useful to the customer investment decision-making and the national energy policy & strategy in Korea.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.5
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• pp.1019-1034
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• 2022

Malware attacks become more prevalent in the hyper-connected society of the 4th industrial revolution. To respond to such malware, automation of malware detection using artificial intelligence technology is attracting attention as a new alternative. However, using artificial intelligence without collateral for its reliability poses greater risks and side effects. The EU and the United States are seeking ways to secure the reliability of artificial intelligence, and the government announced a reliable strategy for realizing artificial intelligence in 2021. The government's AI reliability has five attributes: Safety, Explainability, Transparency, Robustness and Fairness. We develop four elements of safety, explainable, transparent, and fairness, excluding robustness in the malware detection model. In particular, we demonstrated stable generalization performance, which is model accuracy, through the verification of external agencies, and developed focusing on explainability including transparency. The artificial intelligence model, of which learning is determined by changing data, requires life cycle management. As a result, demand for the MLops framework is increasing, which integrates data, model development, and service operations. EXE-executable malware and documented malware response services become data collector as well as service operation at the same time, and connect with data pipelines which obtain information for labeling and purification through external APIs. We have facilitated other security service associations or infrastructure scaling using cloud SaaS and standard APIs.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.161-173
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• 2021

The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.

• Journal of Korean Public Health Nursing
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• v.3 no.2
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• pp.47-76
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• 1989

The objectives of this study was to analyze the major causes of decreasing utilization rate of health care institutios in pilot-project area of regional medical insurance, Kwang-hwa and Kun-wi country. After the implementation of medical insurance, utilization rate of health institutions turned out' to be lower than it was estimated, when the pilot-project of regional medical insurance was planned. It might be due to changes in inhabitant's behavioral attitude toward medical insurance. So this study was made to find measures for financial stability by increasing utilization rate of health care institutions and to be available for basic demand-supply program of medical care. The hypothesis of this study was as follows; First. there is difference in understanding health care institutions between Kun-wi and Kwang-hwa. Second. respondesnts of inquiry survey have exact knowledge of their past experience of treatment taken prior to enforcement of medical insurance, Questionaire survey was made as to each 700 household among total 11, 884 households in Kun-wi and 20,919 households in Kwang-hwa. In case of Kun-wi, 70% of inquired households (491) gave their answers. In Kwang-hwa, the number was 560 households (80% of inquireds). Dollected data was processed and analyzed by way of using SPSS batch system. To evaluate facto rs distribution aspects of data and to make comparison between two area, percentage and $X^2$ distribution were applied. The results were as follows; L The utilization rate of health care institutions in Kun-wi and Kwang-hwa was lower than it was estimated. when pilot-project of medical insurance was planned. 2. Prior to the implementation of medical insurance. inhabitants in two area chose the medical institutions considering such factors. First was medical care fee cheap. second in habitant's residence, Third was the institutions conveniently easy of access. 3. After the implementation of medical insurance. 26.1% of inqurieds in Kun-wi and 41.6% in Kwang-hwa, changed medical institutions. In case of Kwn-wi, from health care institution (p 0.05), and in case of Kwang-hwa, vice versa, from general medical institutions to health care institutions. 4. Evaluation by factors were made such as follows. Inquired gave high marks to following facts: In case of Kun-wi, general medical institutions were difficult of access and relation between patients: was not friendly, but burden of medical expenditure was light. Effects of treatment and facilities was good. In case of Kwang-hwa, inquired gave high evaluation marks to the follow ing facts; facilities of medical institutions was not good, but the burden of medical expenditure was light. 5. After the implementation of medical insurance, the services was evaluated as good, but inquired hopec for lessening the burden of medical expenditure. 6. In case of exact understanding of cost-sharing, the evaluation rate in Kwang-hwa was higher than that of Kun-wi (p < 0.005). And positive attitude toward necessity of medical insurance was also good in Kwang-hwa (p < 0.05). 7. In case of inquired's attitude toward medical institutions, Kwang-hwa showed positive response (p < 0.05) 8. In the case of comparison between general medical institution and health care institution, two area showed similar positive response; medical manpower, facilities of medical institutions and effest: of treatement was good. 9. In comprehensive evaluation of benefit-service; the general medical institution's positiveness was higher than that of health care institutions in Kun-wi. But in Kwang-hwa vice-versa. 10. If the medical expenditure of general medical institution and health care institutions was equal 77% of inquireds in Kun-wi and 59.1% in Kwang-hwa answered that they chose general medical insurance. Considering results above mentioned, the conclusion of this study was made as follows. 1. In Kwang-hwa county, where the understanding of health care institutions's was good, the utilization's of health care institutions was shown high. Therefore, in case of Kwang-hwa, betterment: should be made to induce increasing utilization rate for negative factors of health care institutions. 2. In case of Kun-wi, where the understanding of health care institutions was on the decrease, measures for changing such negative factors should be taken by way of strengthening public relations. And cases of Kwang-hwa should also be studied. 3. On the side of financial stabilization and establishing health care delivery system, primary health care should be available. Therefore, the major cause of inhabitant's avoiding health care institutions should be known. And measures for activating that institutions have to be taken. So, the facilities of health care institution have to be improved up to the level of clinic. And supportive measures for securing equipment and improving health care services should also be taken. It is necessary that strategy for public relations should be employed with policy considerations and supports.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.367-408
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• 2018

This study examines the features of globalization process in GM and Hyundai Motors, especially in the expansion into China auto market, through a joint venture(hereafter JV) research center. Due to the large scale market in China and the 50:50 JV, the two companies had to respond in some way to the Chinese government's request for localization of research and development functions, and their response affected the role of the JV research center. Even though the improvement in technological capability expected from the JV by the Chinese side did not appear well in the early stage in both JV, but relatively the Shanghai GM JV research center had a technological progress compared to the Beijing Hyundai JV research center. This paper explains the differences in the technical capabilities of the two JV research center, despite the same type of JV, as the difference between the status of the Chinese partner and the global strategy of the parent company. SAIC, a Chinese partner in Shanghai GM as a top-tier company, not only has been strongly demanding technology transfer from GM since the beginning of the JV, but has also made efforts to improve its own technical capabilities. Meanwhile, BAIC, a Chines partner in Beijing Hyundai as a mid-tier company, has not been strongly demanding technology transfer and lacked its own research base. Regarding the parent company's global strategy, although both companies controlled the core areas of research and development by their parent companies, GM actively considered using the Chinese RV to develop Chinese and emerging country vehicles. On the other hand, Hyundai Motors responded to the localization demand of the Chinese government while paying more attention to preventing technology leakage through its independent research center in China. The above discussion shows that the process of globalization of a company is a political process in which the global strategy of the parent company and the demands of the stakeholders surrounding the subsidiary are collided and compromised, rather than a process in which the harmony and cooperation between the parent company and its subsidiaries are smoothly achieved as the parent company's policies are unilaterally implemented.