• 반도체디스플레이기술학회지
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• 제19권2호
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• pp.68-71
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• 2020

In this study, SiNx and Al₂O₃ thin film was manufactured using PECVD deposition process and applied to crystalline silicon solar cells, resulting in 16.7% conversion efficiency. The structural improvement experiment of the rear electrode resulted in a 1.7% improvement in conversion efficiency compared to the reference cell by reducing the recombination rate of minority carriers and increasing the carrier lifetime by forming a passivation layer consisting of SiNx and Al₂O₃ thin films through the PECVD process.

• 한국응용과학기술학회지
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• 제17권1호
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• pp.1-5
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• 2000

The selective catalytic reduction(SCR) of nitric oxide by ethane in the presence of oxygen was investigated on Cu-ZSM-5, Co-ZSM-5 and Ga-ZSM-5 catalysts over a range of 400, 450 and $500^{\circ}C$. The catalysts were prepared by ion-exchange method. The composition of the reactant gases were 1000 ppm of NO, 1000 ppm of $C_{2}H_{6}$ and 2.5% of $O_{2}$, and the reaction was conducted in a fixed-bed reactor at 1 atm. For the 20wt% Co-ZSM-5(50) catalyst, the NO conversion reached up to 100%, while the $C_2H_6$ conversion and the CO selectivity were about 50% and 25%, respectively, at $450^{\circ}C$. For the 20wt% Cu-ZSM-5(50) catalyst, the NO conversion and the C2H6 conversion were about 80% and 100%, respectively, but there was no CO produced. The metal ion-exchanged ZSM-5 catalysts exhibited a tendency to increase the NO conversion with the Si/Al ratio of the ZSM-5, that is, NO conversion was inversely proportional to the acidity of the catalysts. But, the effect of the acidity on NO conversion was not so large. From the XRD results of the catalysts before and after SCR reaction it was found that there was no structural change.

• 한국해양환경ㆍ에너지학회지
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• 제14권1호
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• pp.32-39
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• 2011

최근 들어 선박안전 관련 규정이 개정되거나 운항환경이 변화하면 선주사들은 이에 효과적으로 대응하기 위하여 크루즈선을 포함한 여객선을 새로 건조하는 대신 경제적 부담이 적은 기존 선박에 대한 선체개조 즉 컨버전을 많이 실시하고 있다. 컨버전은 선체의 주요 제원을 포함하여 선박의 구조강도, 유체역학적 성능, 여객수 및 화물 용량 등 많은 부분에 변화를 가져오므로 이의 수행에 앞서 세심한 사전 검토가 필요하다. 그러나 아직까지 여객선의 컨버전과 관련된 연구가 수행되지 않았기에, 본 연구에서는 이러한 컨버전을 직접 수행한 컨설팅사들의 보고서를 중심으로 그 동향을 조사하고 분석하여 그 결과 랭스닝 컨버전이 선박의 주요 제원이나 성능에 가장 큰 변화를 발생시킨다는 사실을 확인하였다. 이와 더불어 랭스닝 컨버전을 염두에 두고 건조할 경우 선체개조로 인해 발생하는 문제점들을 최소화하기 위하여 헐 스캔틀링, 선형, 절단 위치 등과 같은 기본설계 단계에서 미리 고려해야 할 요소들에 대해 제시하였다.

• 한국지진공학회논문집
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• 제6권6호
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• pp.7-15
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• 2002

본 논문에서는 다자유도계 구조물의 진동대 실험결과 분석에서 효율적인 지진손상도 평가 및 소성모형 추정을 목적으로, 계측결과를 각 부재별 소성이력으로 환산하고 이 소성이력에 대해 비선형 계수 추정법을 적용하는 다단계 방안을 연구하였다. 이때, 추정된 부재별 소성이력은 부재별 지진 손상도를 평가하는 지표로 활용될 수 있으며, 추정된 비선형 모형 계수를 이용하여 구축된 비선형 다자유도계 구조는 다양한 구조재해석의 모형으로 활용될 수 있다. 제시된 방법의 검증을 위해, 해석적 방법과 실험적 방법의 예제해석이 수행되었다. 예제해석 결과는 해석적 방법과 실험적 방법 모두에서 본 논문의 방법이 매우 효과적임을 보여 주고 있다.

• Corrosion Science and Technology
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• 제17권1호
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• pp.1-5
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• 2018

As structural materials, magnesium (Mg) alloys have been widely used in the fields of aviation, automobiles, optical instruments, and electronic products. There are few studies on the effect of coating conditions on the compositional variation during the formation process of the conversion coatings. Rare-earth based conversion coating on AZ91 magnesium alloy was prepared in ceric sulfate and hydrogen peroxide contained solution. The element composition and valence as well as their distribution in the coating were analyzed with energy dispersive X-ray spectroscopy (EDS), Electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS). The effect of treating process on the element composition were also studied. It was found that the conversion coating surface consists of Mg, Al, O, Ce, and the weight content of Ce in the coating was affected by the treating solution concentration and immersion time; the Ce element was distributed in the coating non-uniformly and existed in the form of $Ce^{+3}$ and $Ce^{+4}$, while the O element existed in the form of $OH^-$, $O^{2-}$, $H_2O$. Based on microscopic analysis results, the electrochemical deposition mechanism on the micro-anode and micro-cathode in the process of the coating growth was suggested.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.349-352
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• 2007

A GFRP based composite blade was developed for a 2MW wind energy conversion system of type class IIA. The blade sectional geometry was designed to have a general shell-spar and shear web structure. The load cases specified in the IEC61400-1 international specification were considered. For withstanding all relevant extreme loads, the structural analysis for the complete blade was performed using a commercial FEM code. The static load carrying capacity, blade tip deflection and natural frequencies were evaluated to satisfy the strength and stability requirements in accordance with the IEC61400-1 and GL Regulations. The prototype blade was passed the structural proof test for GL certification.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.500-503
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• 2003

인터넷 상에서 데이터 교환의 표준으로 광범위하게 사용되고 있는 XML(extensible Markup Language)은 HTML(HyperText Markup Language) 등의 기존의 문서 작성 언어를 대치할 기술로 주목받고 있다. 이러한 XML의 가장 큰 특징은 문서의 구조적인 내용을 표함하는 논리정보와 문서의 스타일을 표현하는 물리적인 정보가 분리되었다는 점이다. 이에 W3C(World Wide Web Consortium)에서는 XML의 스타일과 데이터 변환을 위하여 HTML과 유사한 형식의 스타일 기능을 제공하는 XSL(eXtensible Stylesheet Language)을 권고하였다. 또한 XSL의 변환(XSLT : XSL Transformation)기능은 XML 문서를 다른 데이터 형식으로 변환해주는 기능을 제공하며, 다양한 문서 형식으로의 변환을 통해 스타일 정보를 기술할 수 있다. 그러나 국내에는 XSLT 기술을 이용한 XML 문서 변환 기술이 미비한 실정이며, XSLT 문서를 효율적으로 편집할 수 있는 솔루션에 대한 필요성이 대두되고 있다. 이에 본 논문은 XML 문서를 다양한 문서 형식으로 변환 및 출력이 가능하고, WYSIWYG 환경하에서 XSLT문서를 효율적으로 편집하고 저작할 수 있는 XSLT 문서편집 시스템을 설계 및 구현하였다.

• 한국실내디자인학회논문집
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• 제22권5호
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• pp.51-59
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• 2013

This study aimed to present the possibilities that a variety of conversions can be made in terms of the spatial function through the situation analysis and in-depth case studies, focusing on the cases of the conversion of historic buildings. Literature analysis and case analysis technique were conducted as the research methods. For the literature analysis, the researcher selected 105 cases of conversion-type buildings by recombining and reanalyzing them to space functional changes; the SPSS PC+ 18.0 program was used as the analysis tool to conduct a frequency analysis and cross analysis. In-depth analysis was conducted to investigate the overview of the architecture, building history, spatial functional changes, space program, conservation value, and the conserved parts by selecting 9 cases in Korean and foreign countries that have been recently converted through literature analysis and the results of the study were as follows. 1) As a result of analyzing the changes in function, the highest percentage of the cases was conversion into the cultural function (63.8%). 2) There were cases for conversion into the commercial function, business function, accommodation function and educational function besides cultural function. 3) As a result of spatial program, the attempts to increase the utilization of the building generally by applying the complex space with more than two functions could be seen. 4) The buildings with historical and architectural value were conserved most of the outer wall and some portion of internal parts; the buildings with symbolic value were renovated largely, while preserving symbolic parts; and the buildings with practical value were renovated in a way that maintains the structural parts while changing the interior space to be suitable for their function.

• 전력전자학회논문지
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• 제18권4호
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• pp.376-386
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• 2013

This paper proposes an improved Maximum Power Point Tracking method and design methods of unmanned solar vehicle system by parts of hardware, unmanned driving control and power conversion. The hardware design is offered on the weight reduction and structural reliability by using structural analysis software. The technique of curve fitting is applied to unmanned control system due to minimizing the vehicle's behavior. Furthermore, lateral controller applying actuator dynamics is robust enough to prevent performance degradation by measurement noise regarding position and heading angle. The power conversion system contains battery charger system and tapped-inductor boost converter. In the battery charger system, variable step-size MPPT is conducted for quick response of maximum power point tracking. The validity of the proposed algorithm are verified by simulations and experiments.

• 복식
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• 제58권1호
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• pp.116-132
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• 2008

Continuity and discontinuity is a relative concept, and there are various categories of the continuity and discontinuity in our circumference. In the thought of postmodernism of the late of 20th Century, continuous creations of the difference and the repetition have being regarded as a discontinuity. But, because of that catches the moment occurring qualitative skip though the flowing of the everlasting time, this has been known to a shortsighted viewpoint overlooking characteristic of the qualitative continuity of an organism, which have being created continuous formation for life through the flowing of the time. Therefore, this had studied like this complex social condition and various relationships expressed in modern fashion focusing on permanently creative movements and behaviors equal to the qualitative continuity. This Thesis is following study about continuity, and aims at understanding of those formative characteristics through consideration about characteristics of qualitative continuity. And, this analyzes formative characteristics of the qualitative continuity into 5 sets: enlargement, conversion, structural variability, mutual combination, and deconstruction. This thesis intends to grasp complex modern social phenomenon and modern fashion into qualitative continuity that means continuous formation and the change of various relationships according to recognition about the course toward open thinking.