• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.594-600
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• 2017

HVDC transmission systems can be configured in many ways to take into account cost, flexibility and operational requirements. [1] For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses. For underwater power cables, HVDC avoids the heavy currents required to charge and discharge the cable capacitance of each cycle. For shorter distances, the higher cost of DC conversion equipment compared to an AC system may still be warranted, due to other benefits of direct current links. HVDC allows power transmission between unsynchronized AC transmission systems. Since the power flow through an HVDC link can be controlled independently of the phase angle between the source and the load, it can stabilize a network against disturbances due to rapid changes in power. HVDC also allows the transfer of power between grid systems running at different frequencies, such as 50 Hz and 60 Hz. This improves the stability and economy of each grid, by allowing the exchange of power between incompatible networks. This paper proposed to establish Korean HVDC technology through a cooperative agreement between KEPCO and LSIS in 2010. During the first stage (2012), a design of the ${\pm}80kV$ 60MW HVDC bipole system was created by both KEPCO and LSIS. The HVDC system was constructed and an operation test was completed in December 2012. During the second stage, the pole#2 system was fully replaced with components that LSIS had recently developed. LSIS also successfully completed the operation test. (2014.3)

• Journal of the Korean Society of School Health
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• v.26 no.1
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• pp.1-12
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• 2013

Purpose: To examine the effects of appearance satisfaction on school adjustment among adolescents and, further, the mediating effects of self-efficacy between appearance satisfaction and school adjustment. Methods: Conducted a self-report survey of 640 students consisting of sixth, eighth, and tenth graders in the Jeju Special Self-Governing Province. The collected data were analyzed through the independent-sample t-test, the One-way ANOVA, the Pearson's correlation analysis, and the hierarchical multiple regression analysis using the SPSS WIN 18.0 statistical program. Results: First, boys and girls showed statistically significant differences. Boys reported higher levels of appearance satisfaction, school adjustment, and self-efficacy than girls. Second, there were no significant differences in appearance satisfaction and self-efficacy according to the school level. However, statistically significant differences were observed in school adjustment between sixth and eighth graders. Third, students who thought they belonged to the upper class in terms of academic performance and family economy showed the highest level of appearance satisfaction, school adjustment, and self-efficacy. Fourth, there were positive correlations between appearance satisfaction, self-efficacy, and school adjustment. Fifth, self-efficacy proved to have mediating effects between appearance satisfaction and school adjustment among adolescents. In particular, it had a full mediating effect on the relation between appearance satisfaction and adjustment to school life, one of the subfactors of school adjustment. Conclusion: The results suggest that appearance satisfaction is a factor which influences adolescents' school adjustment and that self-efficacy is an important means of mediating between appearance satisfaction and school adjustment. The study is significant in that it highlighted the importance of self-efficacy as one of the important variables to consider when planning various educational programs to help adolescents adjust to their school. In the light of the findings, in an effort to enhance adolescents' self-efficacy and help them lead a harmonious school life in Korea's so-called 'lookism' society, it is necessary to develop and implement counseling programs and character education materials that help adolescents develop a positive perception of their appearance and build self-esteem and self-confidence.

• Journal of The Korean Association of Information Education
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• v.18 no.2
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• pp.265-274
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• 2014

Rising rate of IT industry in world economy, major countries strengthen IT education. Especially, Owing to SW become significant in IT industry, curriculums of school to enlarge SW education are made in major country. Korea Association of Information Education have studied a new curriculum and suggest a new plan that content of information education classify by 'computer system', 'SW production' and 'fusion activity'. Therefore we study on a curriculum for information of SW production of elementary and middle school. In this paper we firstly suggest object to achieve on information of SW production of elementary and middle school. Next we suggest teaching learning method and evaluation method on them. we expect that the object to achieve on information of SW production we suggest will contribute to develop the curriculum of ICT subject.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.337-345
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• 2012

One of representative Korean fisheries, jigging and angling has 5,700 vessels for squid and hairtail. Hairtail angling is the most typical fishery in Jeju and has an enormous impact on regional economy. However, the price hike in oil and labor costs triggered the necessity of developing a high efficient and energy saving fish luring lamp in recent times. For that reason, this study aimed to analyze the fishing performance of the aircooled LED lamp targeting hairtail angling fishery. The experiment was conducted from September through October in 2009-2011 for a 9.77 ton of fishing vessel setting up 100 lamps. The fishing performance was tested compared with 6 vessels using metal halide lamps in the same waters. As the LED lamp's performance goes up, different lamps were used in 2008 for 80W, 2009 for 120W and 2011 for 180W respectively. The catch and CPUE of the experimental vessel have gradually increased respectively taking the $4^{th}$ and $6^{th}$ place in 2009, the $4^{th}$ and $2^{nd}$ place in 2010, the $1^{st}$ and $1^{st}$ place in 2011 among the 7 vessels. In summary, the LED fishing lamp showed higher fishing performance than comparison groups. It saved 33% of oil consumption and cut down on operating expenses and greenhouse gases emission.

• Journal of The Korean Association of Information Education
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• v.24 no.6
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• pp.563-572
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• 2020

In this study, through a total of 73 lectures and practice for 14 days, preliminary coding instructors developed teaching materials for elementary and junior high school students and verified the effectiveness of the coding instructor training course. The coding instructor training course was hosted by the "◯◯ Creative Economy Innovation Center" for 25 preliminary coding instructors, and was conducted at the "◯◯ University", and 15 elementary and junior high school students who participated in the class were openly recruited. The teaching materials were developed according to the procedure of the ADDIE model based on the results of the pre-requirement analysis conducted with 20 incumbent elementary school teachers majoring in computer education. As a result of running a training course for coding instructors focusing on classroom practice, it was found that the creativity of pre-coding instructors improved.

• The Journal of Fisheries Business Administration
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• v.52 no.4
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• pp.1-11
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• 2021

This study is to investigate the determinants of consumption expenditure by considering potential expenditure factors such as socioeconomic, fishing village tourism behavior, motivation for visits, and optional attributes of tourists at Muchangpo webfoot octopus and finespotted flounder festival in Boryeong. The analysis data are 300 questionnaires of visitors to the festival during the 2018 Muchangpo Mysterious Sea Road Webfoot Octopus and Finespotted Flounder Festival from March 17 to April 8, 2018. As a result of analyzing the factors of consumption expenditure of tourists to the festival in Boryeong, socioeconomic factors such as gender and residential groups outside Chungcheong-do have a positive (+) effect on consumption expenditure. Among the factors of fishing village tourism behavior, the only number of days of stay more than one night has a positive (+) effect on consumption expenditure. In addition, in the analysis of factors for motivation to visit the festival, fun/interest and simple rest/leisure have a significant positive (+) effect on expenditure whereas stress relief have a negative (-) effect on expenditure. In the analysis of the factors of festival selection attributes, tourism facilities has a significant positive (+) effect on expenditure, but natural scenery and excellent natural scenery show a significant negative (-) effect on expenditure. The main implications that can be obtained from the results of this study are as follows. First, it suggests that the promotion should be actively conducted outside of Chungcheong Province in order to achieve the original purpose of revitalizing the local economy from the Muchangpo webfoot octopus and finespotted flounder festival. Second, it indicates that there should be a variety of unique high-quality festival programs differentiated from other local festivals, promoting the existence of simple rest/leisure facilities rather than webfoot octopus boat fishing experiences or natural scenery (i.e., mysterious road and sunset) in order to attract festival tourists' spending at the Muchangpo webfoot octopus and finespotted flounder festival.

• Journal of the Korean Society of Food Culture
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• v.37 no.5
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• pp.385-409
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• 2022

This study investigated the trend of research on 'Food science and Nutrition' in previously published papers in the Journal of Korean Society of Food Culture (JKSFC) from 2000 to 2021. Total number of published papers in this category in the JKSFC was 693 which we classified into 7 main categories and 40 subcategories. Of these, 256 articles were on 'experimental cooking' which was the most studied field among 7 main categories. There was a total of 19 published papers under the category of 'microbiology and fermentation'. A total of 133 articles were published on 'functional foods' and provided essential data for discovering new materials under the theme of various physiological active functions of food materials. Furthermore, 107 articles were included in 'food processing and storage', which provided integrated knowledge of economy, stability and practicality based on various technologies. A total of 144 articles was included in the category of 'nutrition'. Under the category of 'nutrition', the most actively studied topic was 'eating behaviors and dietary habits,' and the trending topic was 'use of healthcare big data.' In conclusion, this review would provide trends of various categories of food science and nutrition area for recent 21 years and suggest directions for future research.

• Journal of Korean Society of Rural Planning
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• v.19 no.3
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• pp.25-36
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• 2013

This study aims to perform the economic analysis to the use of solar power facilities in rural villages considering the climate change scenario. IPCC climate change scenarios in the recently adopted the RCP scenarios (RCP8.5, RCP6.5, RCP4.5, RCP2.6) was used. By RCP scenarios, solar radiation, depending on the scenario in 2100, respectively, 3.6%, 2.5%, 1.9%, 1.1% was assumed to increase. From the economic analysis(payback period is 25 year) on 8 points of each province, in all cases of normal data and four RCP scenarios, at all points analyzed were NPV indicate a negative, BC ratio less than 1.0, respectively. In the case of Mokpo, Chunnam RCP8.5, BC ratio were found to be up to a 0.92, followed by 0.89 in the case of RCP8.5 in Jinju, Kyungnam shows, while the minimum was in Jeju. BC ratio is 1.0 or bigger, in order for the normal solar radiation data in Mokpo, Chonnam was the minimum that it takes 37 years. Similarly, in the case of RCP scenarios, 30 years in Mokpo, Chonnam RCP8.5 and 31 years in the cases of Jinju, Kyungnam and Jeonju, Cheonbuk RCP8.5 were analyzed. It was analyzed that RCP8.5 has the highest value. BC analysis models for each of the factors, the results of the sensitivity analysis, the initial installation costs, electricity sales price, discount rate in the order of economy showed higher sensitivity, and the rest factors showed lower changes. Although there are some differences of solar radiation by region, but in Korea most facilities in rural areas, the use of solar power was considered to be economical enough, considering change of several factors with high sensitivity, such as increasing of government subsidies for the solar power installation of the facility, rising oil prices due to a rise in electricity sales price, and a change in discount rate. In particular, when considering climate change scenarios, the use of solar energy for rural areas of the judgment that there was more economical.

• Review of Culture and Economy
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• v.21 no.1
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• pp.21-61
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• 2018

Most of the Korean performing arts markets are not only small but also show their limitations in terms of their role as a platform for the promotion of performing arts and future growth prospects. This study started from the perception that the domestic performing arts markets need the cooperation between the markets in order to overcome the current situation and become the representative performing arts markets of Asia. To do this, we conducted surveys and in-depth interviews on market collaborations with domestic performing arts officials such as PAMS, Jeju Haevichi Art Festival and G-FAFE. For successful inter-market collaboration, the first is to change ideas and thinking about collaborations, second, to select programs suitable for direct supervision and collaboration based on evaluation of comparative advantage, and third, to establish and operate the 'Performing Arts Market Collaboration Promotion Committee(tentative name)'. And the fourth, starting from the sharing of the network that is most required at this stage, it is necessary to develop the sharing of manpower and places through mutual financial support or sharing between the central government, the metropolitan municipalities.

• The Journal of shipping and logistics
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• v.34 no.4
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• pp.527-544
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• 2018

In this study, SNA analysis was conducted to examine changes in passenger movements in domestic coastal shipping. The validity of derivation of centrality rankings was enhanced by using the connection centrality that reflected weights, which had not been applied in previous research. The results of the connection centrality analysis indicated that the network composition ratio of the South Sea region was high, and the results of analysis of betweenness centrality indicated that ports belonging to the South Sea region recorded high ranks. Jeju Island, which acts as a gateway to the West Sea and the South Sea, Mokpo, which acts as a gateway between the land and islands, those ports that are geographically close to the land, and those ports that are smoothly connected to small ports, were shown to have betweenness centrality. Meanwhile, in the results of analysis of eigenvector centrality, not only ports in the South Sea region but also many ports in the West Sea region were included in the high ranked ones. Using these results, the port authority can identify major ports in domestic coastal shipping, determine the priorities support, identify the current situation of the port connection relations, and establish strategies for management of key development areas. As future studies, studies in the aspect of economy that separate general passengers and island passengers and utilize data such as fares, distances, and time are necessary.