• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.605-611
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• 2019

The fuel sloshing due to the rapid manoeuvre of the aircraft causes significant loads on internal components, which may break components or piping. In particular, a significant load is applied to the joint of the external fuel tank by sloshing movement, which may affect the safety of the aircraft when the joint of the external fuel tank is damaged. Therefore, in order to improve the survivability of aircraft and crew members, the design of external fuel tanks, and joints should be performed after evaluating the sloshing load through a numerical analysis of the fuel sloshing conditions. In this paper, a numerical analysis was performed on the sloshing test of the external fuel tank for rotorcraft. ALE (Arbitrary Lagrangian Eulerian) technique was used, and the test conditions specified in the U.S. Military Specification (MIL-DTL-27422D) was applied as the conditions for numerical analysis. As a result of the numerical analysis, the load on the joint of the external fuel tank was calculated. Moreover, the effects of sloshing movement on structural soundness were assessed through analysis of stress levels and margin of safety on metal fittings and composite containers.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.299-299
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• 2009

Impact evaluation은 현재 시행중이거나 과거에 시행된 프로그램이 국가나 평가대상에 미치는 영향을 정량적으로 측정하는 평가 방법으로 경제적 상황이나 시장 트렌드와 같이 결과에 영향을 미칠 수 있는 외부효과를 제거하고 순수하게 프로그램만의 영향력을 산출한다. 이 방법은 원래 미국의 DOE(Department Of Energy)산하 EERE(Energy Efficiency and Renewable Energy)에서 프로그램 평가를 위해 사용하는 General Program Evaluation Guide에서 언급된 5가지 평가방법 중 하나로 미국의 신재생에너지 프로그램 평가에 주로 사용된다. 이를 한국에 적용하기 위해 미국의 주택용 풍력보급 사업을 평가한 보고서인 Economic Development Impacts of Community wind Projects: A Review and Empirical Evaluation 을 분석 했다. 이 보고서에서는 I/O model을 이용해 직접적 영향력, 간접적 영향력, 유도된 영향력을 구했으며 이를 기존의 평가 보고서와 비교해서 시사점을 도출하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05c
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• pp.1713-1716
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• 2003

기존의 정보화사업 평가는 정성적인 부분과 정량적인 부분으로 이루어 졌으며, 정성적인 부분은 정보시스템의 성능과 사용자 만족도 측면을 중점으로, 정량적인 부분은 비용편익(B/C)분석으로 진행되었다. 최근에 정보화사업 평가에 BSC(Balanced-Scorecard)를 활용한 평가 방안이 제시되어 이를 이용한 평가가 이루어지고 있다. 공공부분의 정보화평가는 행정업무의 효율성 능률성 효과 측면과 대민서비스 측면을 중점으로 진행되고 있다. 본 연구에서는 기존의 BSC를 활용한 정보화사업 평가를 위해 설문 대상을 내부자(업무담당자)와 외부자(일반사용자)로 구분하여, 정보화사업을 평가하고 비교하는 새로운 평가 모형을 제시하고자 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.86-90
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• 2002

IT분야에 대한 정부의 각종 R&D사업 수행 시 과제 선정 및 연구결과에 대한 평가의 투명성, 객관성 및 효율성을 확보하여 사업의 신뢰성을 확보하고 성과를 제고하여야 한다. 1999년 대학기초연구지원 사업에 시범적으로 적용한 전자평가시스템 개발 내용과 그 결과를 위원회 평가와 비교 분석하였다. 1999년에 처음 시도한 전자평가시스템은 과제 제안자 관점에서는 과제접수가 용이하고, 과제 공고부터 결과 정리 시 소요되는 총 소요기간 단축으로 과제 선정을 조속히 확정 가능하여 대민 서비스 제고 차원에서 유용한 평가시스템으로 판단되며, 과제 관리 차원에서도 총 평가비용의 30% 정도의 예산절감 및 10배정도 업무량의 감소 효과를 주는 것으로 분석되었다. 이와 같은 결과를 바탕으로 전자평가시스템이 적용 가능한 사업을 발굴하여 점진적으로 확대 적용하는 것이 타당하며 향후 추진 과제로 산업체가 제안하는 과제내용이 제안자 동의 없이 외부로 유출 방지 등 검토가 필요하다.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.2
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• pp.213-221
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• 2012

The purpose of this study was to evaluate the stability of external stain that long term attrition caused by tooth brushing affected the color variation of external stain of IPS e.max Press Porcelain. The specimen was made by IPS e.max Press LT ingots, and treated the shade of external staning as Orange, A, B, C, D After conducting horizontal toothbrush strokes about 11,000 / 22,000 / 44,000 / 66,000 / 88,000, Color changers of the external stained layer was measured with SpectroShade$^{tm}$ MICRO(MHT, Italy). The result of this study was obtained as follows: 1. After 11,000 strokes, the color changes of shade were greater in Orange shade than the other 4 shade groups. And even though toothbrush strokes were increased until 88,000, there were no statistical significant color changes about the external stain shade variation. 2. The amount of color variation about increasing of toothbrushing strokes was irregular(no consistent increasing, or decreasing), and it was no statistical significant changes According to these results, the long term tooth-brushing doesn't affect the changes of external stain about IPS e.max press porcelain. And it doesn't reduce the stability of external stain clinically. Later, it will be needed to study other factors affecting the external stain.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.511-513
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• 2004

정보화 시대로의 진입에 따라 소프트웨어 개발 품질 프로세스와 품질 관리 기법이 발전하고 있다. 이에 따라 ISO/IEC 9126에서는 소프트웨어 품질 모델을 연구하고 ISO/IEC 14598에서는 소프트웨어 제품의 품질 평가에 대해서 연구하고 있다. 그리고 국내 국방 분야에서는 CBD에 대한 표준화가 진행됨에 따라 CBD 소프트웨어에 대한 품질 평가 방법에 대한 요구가 발생하고 있다. 그러나 기존 산출물 검토 방법은 체계적인 절차와 기준이 없으며 더 나아가 정량적인 품질 평가는 불가능한 상황이다. 따라서 본 논문에서는 CBD 기반 소프트웨어 개발 산출물에 대한 정량적 품질 평가 모델을 제안하고자 한다. 이를 위해 국방 CBD 방법론의 단계별 활동과 활동별 산출물을 살펴보고 품질 평가 대상을 선정하며 대상별 내ㆍ외부 척도를 통해 점검표를 만든다. 그리고 점검표를 통한 점검결과를 분석함으로써 CBD 기반 개발 산출물의 품질을 정량적으로 평가하고 지속적으로 품질을 관리할 수 있다.

• KDI Journal of Economic Policy
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• v.27 no.1
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• pp.39-79
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• 2005

This paper addresses the question of whether a monopolistic banking system can lead to a higher steady state level of capital stock. Information externality has enhanced as the advance of the financial system such as the establishment of the credit bureau system, networking, etc. Hence this paper aims to analyze the effects of both information externality and economic development on the determination of the optimal banking market structure. This paper shows that the presence of information externality together with asymmetric information would explain how a monopoly bank leads to a higher steady state level of capital stock. It also shows that not only under-developed countries but industrialized countries may also benefit from a concentrated banking system. This analysis provides an alternative explanation of the recent deregulation and resulting trends in mergers and acquisitions. This also provides a theoretical foundation to support governments' policy changes toward promoting merger and acquisition activities.

• Journal of the Korea Concrete Institute
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• v.26 no.2
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• pp.125-133
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• 2014

In this study, experimental research was carried out to investigate the seismic and structural performance of precast concrete exterior beam-column joints using bolt type connection and prestressing method. A total of five full-scale exterior beam-column joints were constructed and tested under reversed cyclic loading, controlled by displacement. Results of the test are as follows: Energy dissipation capacity and pinching phenomenon of PC beam-column joints showed disadvantageous behavior compared to RC beam-column joints. However, drift capacity of the PC joint was excellent. Also, yield mechanism concentrated on embedded nuts was suitable as an exterior beam-column joint of lateral load resistance frame. Additional application of prestressing method was also very effective to control excessive pinching and cracking in the joint region, and thus improved an overall seismic performance of the PC joint.

• KIISE Transactions on Computing Practices
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• v.22 no.9
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• pp.461-466
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• 2016

Topic expansion is an expansion method that reflects external data for improving quality of learned topic. The online learning topic model is not appropriate for topic expansion using external data, because it does not reflect unseen words to learned topic model. In this study, we proposed topic expansion method using infinite vocabulary online LDA. When unseen words appear in learning process, the proposed method allocates unseen word to topic after calculating semantic correlation between unseen word and each topic. To evaluate the proposed method, we compared with existing topic expansion method. The results indicated that the proposed method includes additional information that is not contained in broadcasting script by reflecting external documents. Also, the proposed method outperformed on coherence evaluation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.13-22
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• 2015

In this study, a new RCSF (Reinforced Concrete Steel Frame) external connection method is proposed for seismic strengthening of medium-and low-rise reinforced concrete buildings. The RCSF method, proposed in this study, is capable of carrying out the seismic retrofitting construction while residents can live inside structures. The method is one of the strength design approach by retrofit which can easily increase the ultimate lateral load capacity of concrete buildings controlled by shear. The pseudo-dynamic test, designed using a existing school building in Korea, was carried out in order to verify the seismic strengthening effects of the proposed method in terms of the maximum load carrying capacity and ductility. Test results revealed that the proposed RCSF strengthening method installed in RC frame enhanced conspicuously the strength and displacement capacities, and the method can resist markedly under the large scaled earthquake intensity level.