• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.131-138
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• 2018

In this study, we investigated the trend of technological development in major countries related to the propulsion equipment of railway vehicles. The propulsion system is the main equipment of electric vehicles. A lot of time and investment are required in order to ensure the development of technology. Therefore, developed countries have maximized their effort to develop technologies with safety, reliability, and convenience of maintenance. They have also done their utmost to prevent technology transfer to other countries after the development of new technologies. For example, Toshiba of Japan developed a new 3,300V/1,500 A class IGBT power device, but was reluctant to export it to foreign countries in order to protect this technology. In this study, we analyzed the patents applied for related to propulsion control systems and presented the direction of development during the technical development of these systems. The patent analysis of the core technologies was conducted using the Thomson Innovation DB. We examined the number of patents applied for by country, year and major applicant. As a result of the analysis, it was found that the proportion of patent applications per country was in the order of China, 48%, Europe 16.6%, and the United States 14.9%. The patent situation of the top 10 principal applicants revealed that (the top three were?) ABB 14%, GE 13%, and CRRC 12%. At the same time, we also conducted a qualitative analysis of the level of technical development by evaluating such factors as the influence index, quotation, market securing power and citation. Based on the result of the patent analysis, we presented the direction of technical development of the propulsion control equipment of railway vehicles. Based on the analysis results, it was found that domestic applicants considerably reduced their efforts to protect their patents from foreign companies. Nowadays, most of the electric motors used in Korea are induction motors. In advanced countries, permanent magnet electric motors are employed in new railway lines. Therefore, intensive investment is needed in new developments.

• Fire Science and Engineering
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• v.18 no.1
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• pp.54-66
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• 2004

In this article, we are to suggest the hazard-assessing method for the underground pipelines, and find out the pipeline-maintenance schemes of high efficiency in cost. Three kinds of methods are applied in order to refer to the approaching methods of listing the hazards for the underground pipelines: the first is RBI(Risk Based Inspection), which firstly assess the effect of the neighboring population, the dimension, thickness of pipe, and working time. It enables us to estimate quantitatively the risk exposure. The second is the scoring system which is based on the environmental factors of the buried pipelines. Last we quantify the frequency of the releases using the present THOMAS' theory. In this work, as a result of assessing the hazard of it using SPC scheme, the hazard score related to how the gas pipelines erodes indicate the numbers from 30 to 70, which means that the assessing criteria define well the relative hazards of actual pipelines. Therefore. even if one pipeline region is relatively low score, it can have the high frequency of leakage due to its longer length. The acceptable limit of the release frequency of pipeline shows 2.50E-2 to 1.00E-l/yr, from which we must take the appropriate actions to have the consequence to be less than the acceptable region. The prediction of total frequency using regression analysis shows the limit operating time of pipeline is the range of 11 to 13 years, which is well consistent with that of the actual pipeline. Concludingly, the hazard-listing scheme suggested in this research will be very effectively applied to maintaining the underground pipelines.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.1
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• pp.83-138
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• 2017

Korea-China FTA entered into force on the 20th of December 2015, and one year elapsed after its effectuation as the FTA with China, our country's largest trading partner. Therefore, this study looks at the trends of air transport trade between Korea and China, and examines the contents of concessions to the air transport services sector in Korea-China FTA, and analyzes the impact on the air transport sector by Korea-China FTA, and proposes our country's aviation policy direction in order to respond to such impact. In 2016 the trends of air transport trade between Korea and China are as follows : The export amount of air transport trade to China was 40.03 billion dollars, down by 9.3% from the last year, and occupied 32.2% of the total export amount to China. The import amount of air transport trade from China was 24.26 billion dollars, down by 9.1% from the last year, and occupied 27.7% of the total import amount from China. The contents of concessions to the air transport services sector in Korea-China FTA are as follows : China made concessions to the aircraft repair and maintenance services and the computer reservation system services with limitations on market access and national treatment in the air transport services sector of the China Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. Korea made concessions to the computer reservation system services, selling and marketing of air transport services, and aircraft repair and maintenance without limitations on market access and national treatment in the air transport services sector of the Korea Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. The impact on the air transport sector by Korea-China FTA are as follows : As for the impact on the air passenger market, in 2016 the arrival passengers of the international flight from China were 9.96 million, up by 20.6% from the last year, and the departure passengers to China were 9.90 million, up by 34.8% from the last year. As for the impact on the air cargo market, in 2016 the exported goods volumes of air cargo to China were 105,220.2 tons, up by 6.6% from the last year, and imported goods volumes from China were 133,750.9 tons, up by 12.3% from the last year. Among the major items of exported air cargo to China, the exported goods volumes of benefited items in the Tariff Schedule of China of Korea-China FTA were increased, and among the major items of imported air cargo from China, the imported goods volumes of benefited items in the Tariff Schedule of Korea of Korea-China FTA were increased. As for the impact on the logistics market, in 2016 the handling performance of exported air cargo to China by domestic forwarders were 119,618 tons, down by 2.1% from the last year, and the handling performance of imported air cargo from China were 79,430 tons, down by 4.4% from the last year. In 2016 the e-commerce export amount to China were 109.16 million dollars, up by 27.7% from the last year, and the e-commerce import amount from China were 89.43 million dollars, up by 72% from the last year. The author proposes the aviation policy direction of Korea according to Korea-China FTA as follows : First, the open skies between Korea and China shall be pushed ahead. In June 2006 Korea and China concluded the open skies agreement within the scope of the third freedom and fourth freedom of the air for passenger and cargo in Sandong Province and Hainan Province of China, and agreed the full open skies of flights between the two countries from the summer season in 2010. However, China protested against the interpretation of the draft of the memorandum of understanding to the air services agreement, therefore the further open skies did not take place. Through the separate aviation talks with China from Korea-China FTA, the gradual and selective open skies of air passenger market and air cargo market shall be pushed ahead. Second, the competitiveness of air transport industry and airport shall be secured. As for the strengthening methods of the competitiveness of Korea's air transport industry, the support system for the strengthening of national air carriers' competitiveness shall be prepared, and the new basis for competition of national air carriers shall be made, and the strategic network based on national interest shall be built. As for the strengthening methods of the competitiveness of Korea's airports, particularly Incheon Airport, the competitiveness of the network for aviation demand creation shall be strengthened, and the airport facilities and safety infrastructure shall be expanded, and the new added value through the airport shall be created, and the world's No.1 level of services shall be maintained. Third, the competitiveness of aviation logistics enterprises shall be strengthened. As for the strengthening methods of the competitiveness of Korea's aviation logistics enterprises, as the upbringing strategy of higher added value in response to the industry trends changes, the new logistics market shall be developed, and the logistics infrastructure shall be expanded, and the logistics professionals shall be trained. Additionally, as the expanding strategy of global logistics market, the support system for overseas investment of logistics enterprises shall be built, and according to expanding the global transport network, the international cooperation shall be strengthened, and the network infrastructure shall be secured. As for the strengthening methods of aviation logistics competitiveness of Incheon Airport, the enterprises' demand of moving in the logistics complex shall be responded, and the comparative advantage in the field of new growth cargo shall be preoccupied, and the logistics hub's capability shall be strengthened, and the competitiveness of cargo processing speed in the airport shall be advanced. Forth, in the subsequent negotiation of Korea-China FTA, the further opening of air transport services sector shall be secured. In the subsequent negotiation being initiated within two years after entry into force of Korea-China FTA, it is necessary to ask for the further opening of the concessions of computer reservation system services, and aircraft repair and maintenance services in which the concessions level of air transport services sector by China is insufficient compared to the concessions level in the existing FTA concluded by China. In conclusion, in order to respond to the impact on Korea's air passenger market, air cargo market and aviation logistics market by Korea-China FTA, the following policy tasks shall be pushed ahead : Taking into consideration of national air carriers' competitiveness and nation's benefits, the gradual and selective open skies shall be pushed ahead, and the support system to strengthen the competitiveness of air transport industry and airport shall be built, and entry into aviation logistics market by logistics enterprises shall be expanded, and the preparations to ask for the further opening of air transport services sector, low in the concessions level by China shall be made.

• Women's Health Nursing
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• v.3 no.1
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• pp.5-27
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• 1997

This study was carried out to identify the difference between nursing needs and levels of satisfaction of primiparae during the early postpartum period. The goal of the study was to obtain data needed to develope maternal education programs and to improve the nursing quality for primipara. The subjects were 111 primiparae who had normal delivery at 2 general hospitals in the Seoul area. The data was gathered using an 81 items questionnaire which was developed by the researcher from Nov. 30, 1995 to Feb. 5, 1996. Results found are as follows : 1. The characteristics of subjects : The majority of subjects were aged 26-30yrs(60.4%), high school graduated(49.5%), jobless(52.3%), had no religion(49.5%), no antenatal(74.5%), and postnatal education on self and infant care(55.9%). A large proportion of primiparae intended to feed breast milk(49.5%) but in fact only 7.2% fed breast milk while in the hospital. Many subjects perceived that they had reasonable self confidence about self care(46.8%), and infant care(36%). 2. The level of nursing needs of overall nursing care was relatively high(Mn 3.98) but the level of satisfaction was of average level(Mn 3.09). Therefore, difference between the level of nursing needs and satisfaction was significant(p=0.0001). 3. The nursing needs by category of nursing care the highest need was on the education of infant care(4.29), the lowest was on physical care(3.80). The level of satisfaction was higher on environmental care(3.40) and physical care(3.32). But the category that showed the lowest satisfaction was education of infant care(2.67). Hence, difference of categories between the level of nursing needs and satisfaction was significant(p=0.0001). 4. Among items of physical care, observation of primiparas' conditions(4.21), accurate medication and treatment(4.18), care of breast engorgement(4.07) and control of postpartal hemorrage(4.01) showed high nursing needs. On the other hand, only the level of satisfaction was higher on accurate medication and treatment(3.82). The rest of items revealed only average level of satisfactions. Difference of items between the level of nursing needs and satisfaction was significant(p=0.0001) except items of dietary care. 5. Among items of psychological care, 8 items of nursing needs were high(3.72-4.29), expecially detailed explanation on which mothers want to know(4.29), treatment and nursing care they receive(4.23), kind and faithful care(4.22), early contacts with their baby(4.20), and adequate draping during the care and treatment(4.18). Among items of psychological care higher satisfactions were shown on items of kind and faithful care(3.80), personal treatment(3.70), and detailed explanation to mothers, but the least satisfied items was early contact with baby(2.13). Difference between the level of nursing needs and satisfaction was significant(p=0.0001). 6. Among items of environmental care, the highest level of need and satisfaction was on the items of neat bedding and pajamas(3.54). The difference was significant (p=0.0001). 7. Among the items of educational needs on self care, all of 22 items revealed higher educational needs(3.50-4.33) but the levels of satisfaction varied with a range of 2.63-3.42. Among the items the satisfactions were high on items of breast care including massages(3.42), perineal care(3.36) and expression of breast milk(3.32). Less satisfied items were drugs not be taken by breast milk feeder(2.63), maintenance of breast figure(2.76) and postpartum exercise(2.80) and so on. The difference was significant(p=0.0001). maintain 8. Among the items of educational needs on infant care, 19 items revealed higher educational needs(3.28-4.54). And the highest need were on the 3 items of normal growth and development of infant, safety and emergency care, symptoms of sick(4.45) and the meaning of crying of the baby(4.52). The level of satisfaction among items of education of infant care ranged from 2.47 to 3.16. Most satisfied items were buriping(3.16), bathing(3.11) and diapering(3.09). The items of which the mother's needs were high revealed the lowest satisfaction level. The difference was significant (p=0.0001). 9. Relationship between nursing needs and levels of satisfaction among primiparae of different characteristics were as follows : 1) Nursing needs of physical and psychological areas were significantly different among different age levels but no relationship was found on other categories regardless of the level of satisfaction. 2) With regard to different levels of education, some relationship was found in nursing needs of psychological area(p=0.007), educational needs on infant care(p=0.04) and environmental care(p=0.01). Also, the difference of satisfaction level was significant. 3) Working mothers had higher nursing needs and were more satisfied on items of physical care(p=0.05), education on self care and infant care. Difference were significant between nursing needs and level of satisfaction. 4) With regards to different religion a moderate relation was found between nursing needs of environmental care infant care education but no relationship was found on levels of satisfaction. 5) With regards to antenatal education, the mothers who have had no antenatal education revealed higher nursing needs on physical care but those who had antenatal education were more satisfied with education on self care and infant care. The difference was significant. (p=0.0001). 6) With regards to postpartum education, the mothers who have had some sort of postpartum education revealed higher nursing needs on physical and self care. And they were more satisfied with nursing of every category except infant care than mothers who had not any postpartum education. Differences was significant between the nursing needs and levels of satisfaction.(p=0.0001). 7) With regards to breast feeding experience during the hospitalization, those who had no experience of breast feeding revealed higher nursing needs on physical care in contrast to breast feeders, who had higher educational needs on infant care. And breast feeder were more satisfied with all categories. Differences was significant(p=0.0001). 8) With regards to perception of self confidence on self care and infant care, no relationship was found on nursing needs and level of satisfaction in every category of nursing.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.195-220
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• 2018

In this study, we conducted an empirical analysis of the factors that affect the change of Bitcoin Closing Price. Previous studies have focused on the security of the block chain system, the economic ripple effects caused by the cryptocurrency, legal implications and the acceptance to consumer about cryptocurrency. In various area, cryptocurrency was studied and many researcher and people including government, regardless of country, try to utilize cryptocurrency and applicate to its technology. Despite of rapid and dramatic change of cryptocurrencies' price and growth of its effects, empirical study of the factors affecting the price change of cryptocurrency was lack. There were only a few limited studies, business reports and short working paper. Therefore, it is necessary to determine what factors effect on the change of closing Bitcoin price. For analysis, hypotheses were constructed from three dimensions of consumer, industry, and macroeconomics for analysis, and time series data were collected for variables of each dimension. Consumer variables consist of search traffic of Bitcoin, search traffic of bitcoin ban, search traffic of ransomware and search traffic of war. Industry variables were composed GPU vendors' stock price and memory vendors' stock price. Macro-economy variables were contemplated such as U.S. dollar index futures, FOMC policy interest rates, WTI crude oil price. Using above variables, we did times series regression analysis to find relationship between those variables and change of Bitcoin Closing Price. Before the regression analysis to confirm the relationship between change of Bitcoin Closing Price and the other variables, we performed the Unit-root test to verifying the stationary of time series data to avoid spurious regression. Then, using a stationary data, we did the regression analysis. As a result of the analysis, we found that the change of Bitcoin Closing Price has negative effects with search traffic of 'Bitcoin Ban' and US dollar index futures, while change of GPU vendors' stock price and change of WTI crude oil price showed positive effects. In case of 'Bitcoin Ban', it is directly determining the maintenance or abolition of Bitcoin trade, that's why consumer reacted sensitively and effected on change of Bitcoin Closing Price. GPU is raw material of Bitcoin mining. Generally, increasing of companies' stock price means the growth of the sales of those companies' products and services. GPU's demands increases are indirectly reflected to the GPU vendors' stock price. Making an interpretation, a rise in prices of GPU has put a crimp on the mining of Bitcoin. Consequently, GPU vendors' stock price effects on change of Bitcoin Closing Price. And we confirmed U.S. dollar index futures moved in the opposite direction with change of Bitcoin Closing Price. It moved like Gold. Gold was considered as a safe asset to consumers and it means consumer think that Bitcoin is a safe asset. On the other hand, WTI oil price went Bitcoin Closing Price's way. It implies that Bitcoin are regarded to investment asset like raw materials market's product. The variables that were not significant in the analysis were search traffic of bitcoin, search traffic of ransomware, search traffic of war, memory vendor's stock price, FOMC policy interest rates. In search traffic of bitcoin, we judged that interest in Bitcoin did not lead to purchase of Bitcoin. It means search traffic of Bitcoin didn't reflect all of Bitcoin's demand. So, it implies there are some factors that regulate and mediate the Bitcoin purchase. In search traffic of ransomware, it is hard to say concern of ransomware determined the whole Bitcoin demand. Because only a few people damaged by ransomware and the percentage of hackers requiring Bitcoins was low. Also, its information security problem is events not continuous issues. Search traffic of war was not significant. Like stock market, generally it has negative in relation to war, but exceptional case like Gulf war, it moves stakeholders' profits and environment. We think that this is the same case. In memory vendor stock price, this is because memory vendors' flagship products were not VRAM which is essential for Bitcoin supply. In FOMC policy interest rates, when the interest rate is low, the surplus capital is invested in securities such as stocks. But Bitcoin' price fluctuation was large so it is not recognized as an attractive commodity to the consumers. In addition, unlike the stock market, Bitcoin doesn't have any safety policy such as Circuit breakers and Sidecar. Through this study, we verified what factors effect on change of Bitcoin Closing Price, and interpreted why such change happened. In addition, establishing the characteristics of Bitcoin as a safe asset and investment asset, we provide a guide how consumer, financial institution and government organization approach to the cryptocurrency. Moreover, corroborating the factors affecting change of Bitcoin Closing Price, researcher will get some clue and qualification which factors have to be considered in hereafter cryptocurrency study.