• 제목/요약/키워드: Content Structure

검색결과 3,479건 처리시간 0.032초

인산형 연료전지 성능 특성에 미치는 전극 제조 조건의 영향 (Effects of electrode fabrication conditions on performance characteristics of phosphoric acid fuel cell)

  • 송락현;김창수;신동렬
    • 대한전기학회논문지
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    • 제45권2호
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    • pp.224-229
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    • 1996
  • Performance characteristics of single cell in phosphoric acid fuel cell were studied for various electrode fabrication parameters such as teflon content, electrode structure, thickness of electrocatalyst layer, platinum content and electrode area. The performance of single cell was decided from the measured voltage-current through a load change. The electrode of 40wt.% teflon exhibited high initial performance of single cell, but in the long term operation, the cell performance of 45 wt.% teflon was better. Also the single cell appeared good performance in case of electrodes with duplicate structure, thin electrocatalyst in thickness, more platinum content, and small area. These results of cell performance were discussed as related to the electrolyte flooding, formation of 3 phase boundary area, internal resistance of electrode, and microstructure of electrode.

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IP미디어 플랫폼 요소 기술에 관한 연구 (A Study on Technical factors IP media platform)

  • 배재환;이승욱
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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    • pp.498-502
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    • 2008
  • IP 미디어를 서비스하는 IPTV 시스템구조를 보면, 콘텐츠를 수신, 압축 및 암호화하여 송출하는 플랫폼, 전달하는 네트워크 및 콘텐츠를 역변환하여 수신하고, 수신하는 Terminal로 구성된다. 이와 같이 IP 미디어 콘텐츠를 서비스하는 IPTV 시스템 및 플랫폼 구조에 대해서 살펴보고 요소 기술에 대해서 연구 하고자 한다.

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Fe-Co-Ni합금박막의 조성 및 자기적 성질 (Composition and Coercivity of Fe-Co-Ni Alloy Electrodeposits)

  • 예길촌;김용웅;문근호
    • 한국표면공학회지
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    • 제29권3호
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    • pp.195-202
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    • 1996
  • The composition, the microstructure and the magnetic properties(HC and Hk) of Fe-Co-Ni alloy electrodeposits were investigated according to the electrolysis conditions using sulfate bath paddle agitated. The current efficiency of the alloys electrodeposition was considerably low in the range of 16∼50%. The Fe content(wt.%) of the alloy increased from 20% to 57% with current density, while Ni content of them decreased in the range of 70∼24% respectively, and Co content was nearly constant. As a result, Fe/Ni ratio of the alloy increased from 0.3 to 2.0 showing the anomalous codeposition. The structure of the alloy changed from fcc to the mixed one of fcc+bcc with the increase of Fe/Ni ratio. The preferred orientation of the alloy with fcc and bcc structure were (220) and (110) respectively. The alloy with Fe/Ni ratio(0.3∼l.2) had the lowest coercivity of 0.4∼0.8 Oe.

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학술논문의 내용구조에 의한 전문검색시스템 구현과 성능평가에 관한 연구 (A Study on the Implementation and Performance Evaluation of Full-text Information Retrieval System based on Scientific Paper′s Content Structure)

  • 이두영;이병기
    • 정보관리학회지
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    • 제15권3호
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    • pp.73-93
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    • 1998
  • 본 연구는 문헌의 내용구조와 이용자의 정보요구는 밀접한 관련성이 있기 때문에 문헌의 본문을 내용 단위구조로 분할하여 색인한다면 기존의 전문데이터베이스 구축방식에 비해 검색효율을 향상시킬 수 있다는 가설을 설정하고 이를 검증하는데 목적이 있다. 이 가설을 검증하기 위하여 먼저 학술논문의 내용구조 모델을 설정하고, 이 모델을 기반으로 컴퓨터 관련분야 70여편의 학술논문을 대상으로 실험용 전문데이터베이스를 구축한 다음, 이에 대한 검색효율을 측정하여 내용구조 기반 전문검색시스템의 성능을 실험적으로 평가하였다.

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내용 분석을 통한 한국의 학술적 웹 공간 구조 분석 (Ascertaining the Structure and Content of a National Scholarly Web Space Based on Content Analysis)

  • 정영미;유소영
    • 정보관리학회지
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    • 제26권3호
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    • pp.7-24
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    • 2009
  • 학술적 웹 공간을 대상으로 하는 연구는 페이지와 링크의 역동성 때문에 정량적인 방법과 함께 내용 분석 등의 정성적인 방법을 사용하는 것이 필요하다. 따라서 이 연구에서는 내용 분석의 한 방법으로 한국 학술적 웹 공간 내에서 외부 링크로 연결된 페이지 및 링크의 유형을 분류한 후 이를 네트워크 구조 분석에 반영하여 한국 학술적 웹 공간의 특성을 자세히 살펴보았다. 분석 결과 데이터의 수집 시점을 나타내는 기본 네트워크와 내용 분석 시점을 나타내는 활성 네트워크 사이에 구조적으로 큰 차이가 없었으나, 기관 유형별로 다른 기관들을 링크하는 목적이 다르게 나타났다. 그리고 한국 학술적 웹 공간은 여러 중앙성 지수들과 결속계수 간의 설명력이 유사하게 나타나는 형태의 네트워크임을 확인하였다.

고농도의 Ge 함량을 가진 Biaxially Strained SiGe/Si Channel Structure의 정공 이동도 특성 (Hole Mobility Characteristics of Biaxially Strained SiGe/Si Channel Structure with High Ge Content)

  • 정종완
    • 한국전기전자재료학회논문지
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    • 제21권1호
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    • pp.44-48
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    • 2008
  • Hole mobility characteristics of two representative biaxially strained SiGe/Si structures with high Ge contents are studied, They are single channel ($Si/Si_{1-x}Ge_x/Si$ substrate) and dual channel ($Si/Si_{1-y}Ge_y/Si_{1-x}Ge_x/Si$ substrate), where the former consists of a relaxed SiGe buffer layer with 60 % Ge content and a tensile-strained Si layer on top, and for the latter, a compressively strained SiGe layer is inserted between two layers, Owing to the hole mobility performance between a relaxed SiGe film and a compressive-strained SiGe film in the single channel and the dual channel, the hole mobility behaviors of two structures with respect to the Si cap layer thickness shows the opposite trend, Hole mobility increases with thicker Si cap layer for single channel structure, whereas it decreases with thicker Si cap layer for dual channel. This hole mobility characteristics could be easily explained by a simple capacitance model.

Intestinal Structure and Function of Broiler Chickens on Wheat-Based Diets Supplemented With a Microbial Enzyme

  • Iji, P.A.;Hughes, R.J.;Choct, M.;Tivey, D.R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권1호
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    • pp.54-60
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    • 2001
  • A study was conducted to assess the nutritive value of two diets based on a low-energy variety of wheat, RAC C1 and their effects on intestinal mucosal structure and function in broiler chickens. The diets were fed with or without microbial enzyme supplement to male and female broiler chickens. The digesta viscosity was reduced (p<0.001) through supplementation with a microbial enzyme in male and female chicks. Enzyme supplementation also improved the dietary apparent metabolizable energy content (p<0.001) and had slight but non-significant positive effects on chick growth and feed conversion ratio. Intestinal mucosal structure and enzyme function were not affected by microbial enzyme supplement. Male chicks consumed more feeds (p<0.001), attained higher final body weight (p<0.001) and were more efficient at feed utilization (p<0.01) than the female chicks. Except for duodenal villus surface area and ileal protein content, intestinal mucosal structure and enzyme activities were similar between the two sexes and dietary treatment groups. The study showed an improvement in the nutritive value of the diets in the presence of the microbial enzyme supplement.

시료 크기에 따른 CSG재료의 압축강도 및 미세 구조 특성 (Unconfined Compressive Strength and Micro-Structure Properties of CSG Materials Due to Specimen Size)

  • 김영익;김용성
    • 한국농공학회논문집
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    • 제52권4호
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    • pp.93-101
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    • 2010
  • The purpose of this study is to provide basic data for utilization in environment-friendly and economically outstanding CSG construction method by physical and mechanical properties of CSG materials including characteristics of uniaxial compressive strength, microscopic structure and freezing and thawing resistance in accordance with the cement content and curing time of the cement, and size of specimen. In this study, specimens with cement content of 4, 6, 8 and 10% of the total weight were, and, in order to examine the characteristics of the sizes of specimen, specimens with ${\Phi}50{\times}100mm$, ${\Phi}100{\times}200mm$ and ${\Phi}150{\times}300mm$ were manufactured to assess the features including compressive strength, microscopic structure, freezing and thawing, and degree of wet-dry. As results, it was found that with greater size specimen or contents of cement in the specimen, compressive strength, freezing and thawing resistance, and wet-dry resistance increase. Moreover, reactive products for each size of specimen were examined and it was possible to verify that some typical needle structured ettringite was generated due to blending of cement through microscopic structure analysis such as SEM and EDS analysis.

박물관 웹 사이트의 메뉴구조 및 콘텐츠 분석에 관한 연구 (A Study on the Analysis of Menu Structure and Contents in Museum Web Sites)

  • 노동조;이기리
    • 한국비블리아학회지
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    • 제30권4호
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    • pp.5-27
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    • 2019
  • 본 연구는 국내 박물관 웹 사이트의 메뉴구조 및 콘텐츠 분석을 통하여 박물관 웹 사이트 메뉴구조의 발전방향을 제시한 것이다. 이를 위하여 국내 27개의 국립·공립·대학 박물관을 대상으로 메뉴구조를 콘텐츠 영역으로 구분, 정리하고 인포메이션 아키텍처의 구성요소인 조직화 시스템, 레이블링 시스템, 내비게이션 시스템의 측면에서 분석하였다. 본 연구의 결과, 적절한 폭과 깊이의 계층구조, 명확하고 일관성 있는 레이블 사용, 소장품 검색 기능 제공 및 소장품 현황 업데이트, 웹 사이트 오류에 대한 즉각 수정, 웹 사이트의 지속적 관리 등을 발전 방안으로 제시하였다.

Genetic diversity and population structure of rice accessions from South Asia using SSR markers

  • Cui, Hao;Moe, Kyaw Thu;Chung, Jong-Wook;Cho, Young-Il;Lee, Gi-An;Park, Yong-Jin
    • 한국육종학회지
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    • 제42권1호
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    • pp.11-22
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    • 2010
  • The population structure of a domesticated species is influenced by the natural history of the populations of its pre-domesticated ancestors, as well as by the breeding system and complexity of breeding practices implemented by humans. In the genetic and population structure analysis of 122 South Asia collections using 29 simple sequence repeat (SSR) markers, 362 alleles were detected, with an average of 12.5 per locus. The average expected heterozygosity and polymorphism information content (PIC) for each SSR locus were 0.74 and 0.72,respectively. The model-based structure analysis revealed the presence of three clusters with the 91.8% (shared > 75%) membership, with 8.2% showing admixture. The genetic distances of Clusters 1-3 were 0.55, 0.56, and 0.68, respectively. Polymorphic information content followed the same trend (Cluster 3 had the highest value and Cluster 1 had smallest value), with genetic distances for each cluster of 0.52, 0.52, and 0.65, respectively. This result could be used for supporting rice breeding programs in South Asia countries.