• The Journal of the Korea Contents Association
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• v.12 no.9
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• pp.489-499
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• 2012

Most roads in Korea are constructed through a riverside or among the mountains due to geographical characteristics, and composed of various connection roads and complex networks, which makes it susceptible to a fog, rainfall and snowfall and causes serious negligent accidents due to misperception of network while driving. This study amis at securing original technology to provide traffic information, utilizing the road surface by grafting LED and optical technology highly recognized in terms of energy efficiency recently onto ITS, thereby developing next-generation ITS service. To support the research development, H/W was developed and field test was conducted. In addition, the customer satisfaction survey towards equipment, an end product of this research development was also carried out to find out what it means to customers potentially.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.165-173
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• 2021

Anti-glare (AG) coating films are applied to various display fields such as liquid crystal displays, LED lighting, and touch panels. In this study, micrometer-sized silica particles were added as fillers in the UV-curable coating solutions to provide anti-glare effect. During this process, the effects of the particle size, content, stirring time, and mixing ratio of silica particles of different sizes were investigated on the haze values and visible light transmittance of the coating films. As a result, as the size of the silica particles increased and the content of the silica particles increased, the haze values increased, but the visible light transmittance decreased. On the other hand, the stirring time did not significantly affect the haze value and transmittance of coating films. In addition, as the mixing ratio of large-sized silica particles increased, the haze value increased, but on the contrary, the visible light transmittance decreased.

• Journal of Labour Economics
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• v.40 no.1
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• pp.37-68
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• 2017

This study analyzes the relationship between household debts and married female's labor supply. For doing this we construct effective interest rate faced by each household using interest paid amount and household financial debt amount. The effective interests rate for the households which have no financial debt are estimated by Heckman Selection model. The estimation results show that the increase in effective interest rate has led to the expansion of married women's the labor market participation. This suggests a possibility that negative scenarios resulting from an increase in interest rate can be partially offset by an increase in household labor supply and a rise in labor income.

• Journal of Labour Economics
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• v.34 no.1
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• pp.103-138
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• 2011

This paper examines the changes in relative wage of top 10 college graduates to the other college graduates among the age group of 26-28 years using Korean Labor and Income Panel Study (KLIPS). From 1999 to 2008, the wage differential between top 10 college graduates and the other college graduates increased in South Korea. This wage differential seems to persist along with their age. Within industry wage differential among college graduates also rose but in the late 2000s it became smaller than the wage differential within firm size and industry. Increase in elite college wage premium has led to recent changes in college wage premium.

• Journal of Environmental Science International
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• v.22 no.9
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• pp.1171-1180
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• 2013

Recent climate change has led to fluctuations in agricultural production, and as a result national food supply has become an important strategic factor in economic policy. As such, in this study, panel data was collected to analyze the effects of seven meteorological elements and using the Lagrange multipliers method, the fixed-effects model for the production of five types of food crop and the seven meteorological elements were analyzed. Results showed that the key factors effecting increases in production of rice grains were average temperature, average relative humidity and average ground surface temperature, while wheat and barley were found to have positive correlations with average temperature and average humidity. The implications of this study are as follow. First, it was confirmed that the meteorological elements have profound effects on the production of food crops. Second, when compared to existing studies, the study was not limited to one food crop but encompassed all five types, and went beyond other studies that were limited to temperature and rainfall to include various meterological elements.

• Resources Recycling
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• v.24 no.2
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• pp.23-28
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• 2015

Most of the domestic need for tin rely on imports. In this work, a pyrometallurgical process was investigated to recover pure tin from the tin oxides in tin bath which results from the production of flat glass and LCD panel. From the results on the effect of reaction temperature, the highest recovery percentage of tin was obtained at $1350^{\circ}C$. The recovery percentage of tin was improved to 88% by employing the first and second smelting step. Electrorefining of the crude tin thus obtained led to pure tin with purity higher than 99.9%.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.4
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• pp.67-77
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• 2021

Space development has been led by the state due to huge investment, risks of development failure, and restrictions on international cooperation on technology development and transfer. For this reason, it has been developed mainly by some advanced countries and industrial network formed among them. However, Korean space industry is being promoted by the successful launch of 'KSLV-I' and 'CAS 500-I' and the space launch vehicle "KSLV-II" under development. Recently, Korea and U.S. agreed to end bilateral missile guidelines. Therefore it is expected that development of Korean space industry will be accelerated due to the disappearance of the constraining factors for the development of space launch vehicles. Accordingly, this study examined the development and formation of the Korean space industry through the framework of network analysis. Based on this, the effect of structural position in the industrial network as a resource on the performance of Korean space companies was examined. Panel analysis was applied. Through this study, ideas for fostering the domestic space industry and implications for national policy related with building an industrial ecosystem are derived. It contributes to the development of space industry in Korea.

• Journal of Technology Innovation
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• v.22 no.3
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• pp.37-63
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• 2014

This study is intended to demonstrate how different factors induce the Korean government's direct investment in research and development according to the type of business enterprise in Korea. We analyzed that what factors made the government directly invest in research and development by using a total of 18,272 company panel data, which are not limited to specific industries or government-led research and development (R&D) programs. The results showed that the direct investment for R&D by the government led to the increase in the number of researchers in SMEs. For major companies, the direct investment resulted in the increase of sales and company's own R&D expenses. Moreover, this study found that government's direct support for R&D even led to the decrease of SMEs' own R&D expenses; however, this result was not statistically significant. In addition, the most significant factor to increase both SMEs' and major company's own R&D expenses was the sales amount of the company, rather than government's direct investment for R&D. The factor that increases sales was the company's own R&D expenses, rather than government's direct investment for R&D. Through the analysis using Mixed Effects Model, this study suggested the policy should be changed to make SMEs invest in its own R&D expenses, rather than to secure researchers of SMEs by government's direct investment for R&D.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.209-214
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• 2017

The purpose of this study is to identify the factors that led greenhouse grape farms to delay their heating periods after the coming into force of the Korea-Chile Free Trade Agreement (FTA). Panel data on the cropping (system) changes from 2004 through 2016 were used for the analysis. According to the panel logistic model, the estimated coefficient of the cultivation area was 0.0002, which was statistically significant at the 10% significance level, the estimated coefficient of grape imports was 1.4258, which was statistically significant at the 1% significance level, and the estimated coefficient of the regional dummy was 0.808, which was statistically significant at the 5% significance level. The results indicated that the use of wider cultivation areas, increase in grape imports, and colder climate(in the mid-northern part of Korea) increased the likelihood of delayed heating. The Korean government is offering direct payment programs and business closure support to the greenhouse grape farmers. While these actions can relieve the damage caused by the increase in grape imports, they will not provide the ultimate solution. Various support measures are needed, such as renewing the varieties to meet the changing demand of grape consumers, providing agricultural materials to reduce the heating expenses, and modernizing greenhouse facilities to improve the energy efficiency and reduce the costs.

• Korean Journal of Social Welfare Studies
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• v.43 no.1
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• pp.339-363
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• 2012

This study examines the effects of adolescents' volunteer activities on their development of sense of community. When examining the effects of volunteer activities, both quantity and quality sides of volunteer activities were considered in the research model and besides the direct effects of volunteer activities on their sense of community, the mediating role of self-esteem and peer attachment were also examined. The data set of conducted by National Youth Policy Institute was reanalyzed for this study. The subjects of this study were 1,426 first-grade middle school students who had experiences of volunteer activities. The results of the study are as follows. First, the total hours of volunteer activities and the satisfaction with volunteer activities were positively related to their sense of community respectively. In an integrative model which combines both quantity and quality aspects of volunteer activities, however, only the satisfaction with volunteer activities was found to be significant. This means that the satisfaction with and reflective learning after volunteer activities are more important sides of adolescents' volunteer activities than whether and how many times they had experiences in volunteer activities. Second, the satisfaction with volunteer activities was found to enhance adolescents' self-esteem and peer attachment and the changes in their personal traits again led to a higher sense of community. Therefore, both the direct effects of volunteer activities and indirect effects through self-esteem and peer attachment were proved. Based on the results of the study, the need and ways to improve the management system of adolescents' volunteer activities were suggested.