• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.34.2-34.2
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• 2010

Cu(In,Ga)Se2 (CIGS) 화합물 반도체를 기반으로 한 태양전지는 박막태양전지 기술 중 세계최고효율을 기록하고 있다. CIGS를 합성하는 방법은 동시증발법, 스퍼터링/셀렌화 등의 진공방식과 나노분말법, 전착법, 용액법 등의 비진공방식이 있으나, 현재까지 진공방식이 양산기술로서 완성도가 높은 것으로 알려져 있다. 특히 스퍼터링에 의한 전구체 박막 증착과 셀렌 분위기에서의 열처리 공정을 결합시킨 2단계 공정은 동시증발법에 비해 대면적 모듈 제조에 유리한 것으로 알려져 있다. 셀렌화 공정은 통상 반응성이 매우 높은 H2Se 기체를 이용하고 있으나, 부식성 및 안전성 문제를 해결하기 위해 추가적인 설비가 요구되므로 제조비용을 높이는 단점을 갖는다. 한편, Se 증기를 이용하면 안전성은 담보되나 낮은 반응성으로 인해 고온에서 장시간 열처리를 해야하는 문제를 안고 있다. 본 연구에서는 새로운 Se 증기를 사용하되 반응효율을 높일 수 있는 새로운 셀렌화 열처리방법을 제시하고자 한다. 기존의 Se 증기가 별도의 증발원을 이용하여 공급된 것과는 달리, 금속전구체 직상부에 Se이 코팅된 별도의 커버글라스를 위치시켜 Se의 손실을 최대한 억제하였다. Se 커버글라스가 밀착된 금속프리커서를 $200{\sim}600^{\circ}C$ 온도범위에서 열저항가열로 내부에서 열처리하였으며, 추가로 Se을 공급하지는 않았다. 이와 같은 방법 제조된 CIGS 박막의 물성을 X선회절법, 주사전자현미경 등으로 관찰하였으며, 예비실험결과 비교적 낮은 온도에서 chalcopyrite 상이 형성됨을 확인하였다. 근접셀렌화에 의해 제조된 CIGS 박막이 적용된 태양전지를 제조하여 셀렌화 공정변수에 따른 소자특성변화를 제시하고자 한다.

• Korean Journal of Construction Engineering and Management
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• v.12 no.3
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• pp.53-61
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• 2011

After several collapse accidents of large structures in the early 1990s in Korea, the government enacted a law that architectural, engineering and construction firms are obliged to have insurance for projects over a certain size. Particularly, with regard to insurance in design and construction supervision works (i.e. engineering insurance), although several operation-based problems were pointed out from practitioners, still little research has been done on analyzing current regnlartory and operational state and suggesting policy alternatives. Hence, this study applies Delphi technique to solicit current operational problems and propose a series of improvements on engineering insurance based on interview surveys targeting major market participants: municipalities, engineering firms, and insurance companies. Key findings culminate in adopting guarantee limits based on credit evaluation, abrogating joint surety, covering a loss of life, increasing insurance entrance fee, extending time covered, and etc. Reaching a consensus on the proposed alternatives between the market participants will form the foundation for sound developments of construction design and engineering industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.622-631
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• 2016

This study examined 316 soldiers in the South Korean Army and the mediation effects of social support on bullying and frustration. Bullying, social support, and frustration showed average scores of 2.23, 3.60, and 2.75 points, respectively. There was a positive correlation between bullying, social support, and frustration. All of the subordinate variables of bullying showed significant impacts on frustration (p<.05), with psychological harassment showing the greatest impact (${\beta}=.340$), followed by bullying in interpersonal relationships (${\beta}=.149$) and bullying at work (${\beta}=.130$). In all the interaction items of the subordinate variable bullying ${\times}$ social support, bullying had a significant impact on frustration at p<.01, while the highest impact was shown in the interaction item of bullying ${\times}$ member support (${\beta}=.456$). The results imply that intangible combat power and solidarity among soldiers can be guaranteed only when superiors and peers provide full support for soldiers who are victims of bullying.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2141-2149
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• 2009

This research is based upon the nursing statistical data published by the Institute of Nursing Policy in 2007, on behalf of Korea nursing association. We analyzed the problems on the healthcare human resources supply in Korea. We suggest that a solution is to adopt immigration policy for foreign workforce employment. The result of the research shows that more than 1,000 nurses are registrated every year except for 2004, according to the yearly status of healthcare jobs. The variance of doctors' registration was quite significant. Compared to 750 registrations in 2004, 4000 doctors were registered in 2002. The healthcare accounts for the property of citizens in terms, which represents the health and lives of everyone, so the country must take all measures to supply the healthcare services in need. Focusing on the underdeveloped region where it is difficult to approach the medical services, the foreign workforce could be added into the healthcare profession field. We conclude that employing foreign healthcare professionals will contribute to the improvement of lives in those people living in underdeveloped region, as well as unity of the local community.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.101-108
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• 2013

In this paper, we examine the impact of family ownership mechanism on the firm's debt policy. Our results show that family firms tend to have a lower debt level, compared with non-family firms. Foreign investors are found to lead to a reduction in the firm's debt level through their monitoring incentives for dominating large shareholders. The firm's profitablily is related to a lower level of debt, whereas higher tangible assets and firm size are positively associated with high debt ratios due to the possibility of large collateral assets. Some implications are that foreign investors can reduce the agency costs of dominating large shareholders in family firms through monitoring activities, thus enhancing the efficiency of business decision-makings.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.3827-3833
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• 2011

This paper performed empirical tests of the validity of the pecking order theory which explains financing behavior of firms under information asymmetry. The results of regression analyses using the data of listed manufacturing companies in the Korean Stock Market from 1981 to 2010 have shown strong evidences supporting the pecking order theory. Especially regression coefficients of change of debt on funds deficit and control variables were found to be almost (+1) with statistically significance, which is interpreted as being consistent with the pecking order theory. Same results were found when I performed regression analyses by dividing the sample period into pre-currency crisis period, currency crisis period and post-currency crisis period and using 2 regression models. Change of tangible asset were found to function as collateral rather than reducing information asymmetry and as the firm size decreased, use of debt increased and as profitability increased use of debt decreased, which are consistent with the pecking order theory.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.4
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• pp.483-488
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• 2010

An online monitoring based upon sensor system is essential to assure both efficient operation and safety in the power plant. Of great importance is modeling for auto-association (AA) in online monitoring technique. The objective of auto-associative models lies in predicting true values of plant operation parameters from sensor signals transmitted. This paper presents two AA models using Support Vector Regression (SVR) and Partial Least Square Regression (PLSR). The presented models are useful, in particular, when there are many parameters to monitor in the power plant. Illustrative examples are given by using a real-world plant dataset. AA performances of SVR and PLSR are finally summarized in terms of accuracy and sensitivity. According to our results, SVR shows much higher accuracy and, however, its sensitivity is relatively degraded.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.269-273
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• 2021

US Army Found Five Lessons For the Urban Operations After Implemented Offensive Operations in Mosul, Iraq for the First time in the 21st Century. Based on these lessons the US Army Adds Spur Preparing For Future Megacity Operations Such as Weapon System, Warfighting Concept, Structure and etc. Korean peninsula experiences rapid Urbanization, so the Megacities are also Expected to Increase by this trend. So the ROK army also need to Benchmark the US Counterpart, so that the Organization needs to prepare following Elements. First, Establishing Collective Intelligence Platform for uture Megacity ops. Second, force Builing Optimized for the Megacity Operations(Warfighting Concept, Weapon System, Structures), Lastly, Establishing Megacity Synthetic Training field. By Preparing so, ROKA can Assure its Success in Future Warfare.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.435-440
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• 2022

This study analyzed the impact of changes in real estate prices on the soundness of Korean banks using multiple regression models. As a result of the analysis, changes in real estate prices significantly increase the banks' non-performing loans through the increase in loans. Among macroeconomic variables, short-term interest rates were found to have a significant effect on all soundness indicators such as BIS capital adequacy ratio, non-performing loans ratio, and liquidity coverage ratio. Among the bank characteristics indicators, the loan growth rate had a significant negative effect on BIS capital adequacy ratio, and the real estate mortgage rate had a significant positive effect. In additional, it was found that non-performing loans ratio and liquidity coverage ratio had a negative effect on BIS capital adequacy ratio.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.223-238
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• 2022

The discovery of new historical resources is important in that it ensures the sustainability of future researches and enables new interpretations and expansion of them. The purpose of this study is to describe the characteristics of Chinese reports related to the newly discovered Gwangju Student Movement in terms of contents. In particular, since Chinese reports contain the same expressions and contents, we tried to figure out which materials from Korea and Japan were cited the same and what kind of relationships there were. The analysis results are as follows: First, the relationship between the reports on December 6, 1929, which were newly claimed as the first reports, and the Gwangju Student Movement was explained in detail. Although there is no specific indication that the distributing of manifesto and arresting case on December 6th in Seoul was related to the Gwangju Student Movement, it should be viewed as the first reports made to support it. Second, in previous studies, it was revealed that the contents known as the newspaper's own reports were actually quoted from previous reports in Korea or Japan. Third, it was confirmed that the contents of reports could be affected by the citation reports according to the political characteristics of the newspapers.