• 제목/요약/키워드: Background current

검색결과 1,970건 처리시간 0.027초

HVDC 컨버터 시스템에서 라디오 장해에 대한 대책 (Reduction Method of Radio Interference in HVDC Converter System)

  • 김찬기;최순호
    • 전기학회논문지
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    • 제61권6호
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    • pp.833-837
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    • 2012
  • In HVDC System, the rapid voltage breakdown between anodes and cathodes during valve firing causes radio interference in HVDC converter station. These voltage breakdown causes steep current pulse and inject current in system. As a result, harmonic frequencies are generated from valve, switchyard. In this paper, theoretical background of radio interference in HVDC converter is discussed and its reduction method for radio interference is proposed.

국내 종합병원에서의 정보자원의 확보에 관한 연구

  • 김영문;서창교
    • 한국정보시스템학회지:정보시스템연구
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    • 제4권
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    • pp.65-82
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    • 1995
  • This paper investigates the current status of the acquisition of information resources at the domestic hospitals. First of all, as a theoretical background, the concept of hospital information systems and the acquisition of information resources are reviewed. Second, as a research methodology, samples, data collection methods, and data analysis methods are discussed. Third, research hypotheses, operational definitions of the research variables and measurement are discussed. Fourth, as research results, characteristics of the samples and the current situations of the acquisition of information rourses are discussed based on the five research hypotheses.

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현대 건축에 있어서 유기적 디자인 경향에 관한 연구 (A Study on tendency of organic design in modern architecture)

  • 박경진;우성호
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2002년도 춘계학술발표대회 논문집
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    • pp.116-120
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    • 2002
  • The purpose of study is to know how a tendency of organic design have become in mordern architecture-from 20C. architecture to current architecture. In particular, I want to find it out in digital architecture-one of current architecture. To do this, first, I research concept, categories, characteristics of organic design in mordern architecture. Second, I observe theoretical background and analyze design characteristics of digital architecture. Finally, I recognize form of digital architecture have a side of a tendency of organic design.

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Influence of the Thin-Film Ag Electrode Deposition Thickness on the Current Characteristics of a CVD Diamond Radiation Detector

  • Ban, Chae-Min;Lee, Chul-Yong;Jun, Byung-Hyuk
    • Journal of Radiation Protection and Research
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    • 제43권4호
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    • pp.131-136
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    • 2018
  • Background: We investigated the current characteristics of a thin-film Ag electrode on a chemical vapor deposition (CVD) diamond. The CVD diamond is widely recognized as a radiation detection material because of its high tolerance against high radiation, stable response to various dose rates, and good sensitivity. Additionally, thin-film Ag has been widely used as an electrode with high electrical conductivity. Materials and Methods: Considering these properties, the thin-film Ag electrode was deposited onto CVD diamonds with varied deposition thicknesses (${\fallingdotseq}50/98/152/257nm$); subsequently, the surface thickness, surface roughness, leakage current, and photo-current were characterized. Results and Discussion: The leakage current was found to be very low, and the photo-current output signal was observed as stable for a deposited film thickness of 98 nm; at this thickness, a uniform and constant surface roughness of the deposited thin-film Ag electrode were obtained. Conclusion: We found that a CVD diamond radiation detector with a thin-film Ag electrode deposition thickness close to 100 nm exhibited minimal leakage current and yielded a highly stable output signal.

중국 연변 조선족 유아 양육 실제에 나타난 시대성과 민족성 이슈 (Current and Ethnicity Issues Represented in Child-Rearing Practices of Korean-Chinese Families in YanBian, China)

  • 윤갑정;고은경;정계숙
    • 아동학회지
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    • 제29권5호
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    • pp.31-50
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    • 2008
  • The current and ethnic issues represented in child-rearing practices of Korean-Chinese families in YanBian, China, were studied with the participation of 7 primary caregivers (4 mothers and 3 grandmothers) of young children who were interviewed and observed in their homes. Current issues were categorized as competitive bilingual ability, expectations about third language learning (English), expectations of high academic accomplishment and early education, and economic challenges in parenting. Ethnicity issues included ethnic pride as Korean-Chinese, conflicts of ethnic education, participation in local Korean culture, and rearing the child to have the self-expressive and assertive characteristics of typical Korean children. Results were discussed in terms of understanding and supporting child-rearing of minorities and families with multi-cultural background.

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위성 자세제어용 RLG 전류 안정화 회로 설계 (DESIGN OF THE RLG CURRENT STABILIZER CIRCUIT FOR ATTITUDE CONTROL IN THE SATELLITE)

  • 김의찬;최재동
    • Journal of Astronomy and Space Sciences
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    • 제23권2호
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    • pp.161-166
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    • 2006
  • 이 논문에서는 위성 자세제어용으로 사용되는 RLG(Ring Lager Gyroscope) 전류 안정화 회로에 대해서 설명한다. RLG는 헬륨-네온레이저의 공진기 내에서 샤냑효과를 이용한다. 두 방전전류의 차이는 자이로 바이어스 오차의 한 부분을 차지한다. 전류 안정화회로의 이론적 배경과 설계과정에 대해서 기술하고, 입력전압 시험, 온도시험을 통하여 검증하였다.

저항형 초전도 한류기를 위한 배전개통의 모델링과 적용 (Distribution System modeling and Application for HTS Resistor type FCL)

  • 최흥관;윤재영;김종율;이병준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.250-252
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    • 2002
  • Nowadays, one of the serious Problems in KEPCO system is the more higher fault current than the SCC(Short Circuit Capacity) of circuit breaker. There are many alternatives to reduce the increased fault current. As the superconductivity technology has been develops, the HTS-FCL(High Temperature Superconductor-Fault Current Limiter) can be a one of the attractive alternatives to solve the fault current problem. Under the this background, this paper presents distribution system EMTDC modeling and the application of EMTDC model for resistance type HTS-FCL in the developed distribution system model.

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3차원 객체 복원을 위한 정규 상관도 기반 다중 시점 배경 차분 기법 (Normalized Cross Correlation-based Multiview background Subtraction for 3D Object Reconstruction)

  • 팽경현;황성수;김희동;김수정;유지성;김성대
    • 전자공학회논문지
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    • 제50권6호
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    • pp.228-237
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    • 2013
  • 본 논문에서는 배경과 객체의 색상이 유사한 상황에서 강인한 정규 상관도(Normalized Cross Correlation) 기반 다중 시점 배경 차분 기법을 제안한다. 인위적으로 배경을 구성한 경우가 아닐 경우, 다중 시점 영상의 배경 영상에서 객체로 인해 가려지게 되는 영역들은 서로 다른 색상을 가지고 있을 확률이 높다. 그러나 객체의 등장으로 인해 이러한 영역들은 서로 유사한 색상을 가지게 된다. 이에 기반하여 본 논문은 GoNCC(Graph of Normalized Cross Correlation)을 제안한다. GoNCC는 임의 시점 영상의 한 화소와 에피폴라 제약조건 관계에 있는 인접 영상 내 화소와 해당 화소와의 정규 상관도 값의 분포를 의미한다. 제안하는 다중 시점 배경 차분 기법은 현재 영상의 GoNCC와 배경 영상의 GoNCC를 비교함으로써 이루어진다. 계산량을 줄이기 위해 다중 시점 배경 차분 기법을 모든 화소에 적용하지 않고 간단한 단일 시점 배경 차분 기법으로 판단하기 어려운 영역에 대해서만 제안 방법을 수행한다. 실험 결과 단순한 단일 시점 배경 차분 기법에 비하여 매우 우수한 성능을 보였고, 기존의 다중 시점 배경 차분 기법에 비해서도 보다 정확하게 객체 영역을 검출하는 것을 확인하였다.

인터넷 의류쇼핑몰 상품 사진의 표현형식과 배경이 소비자의 지각에 미치는 영향 (The Effects of Product Presentation and Background of Photos in Internet Shopping Malls on Consumer Perceptions)

  • 김서윤;백기영;최자은;이현화
    • 한국의류학회지
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    • 제38권4호
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    • pp.467-481
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    • 2014
  • This study examined consumer responses of photos used in Internet shopping malls. The content analysis conducted a preliminary study of the top 100 online shopping malls to investigate current website practices. Stimuli based on the preliminary study. The present study was a $2{\times}2$ factorial design that evaluated two independent variables of product presentation and background. We analyzed 410 responses derived from the descriptive analysis, factor analysis, and covariance analysis through SPSS 20.0. The results showed that a product presentation was significantly different in attractiveness, informativeness, satisfaction, and repurchase intention after controlling apparel items and model. This product presentation in everyday life had greater mean values than product presentation with the posing model. The background had a significant mean difference in all consumer responses expect for attractiveness. Overall product presentation in everyday life and indoor cases were evaluated as most positive by the respondents. The findings provide practical implications for online shopping malls integrating product presentation.

배경 모델과 주변 영역과의 상호관계를 이용한 다중 이동 물체 추적 (Multiple Moving Object Tracking Using The Background Model and Neighbor Region Relation)

  • 오정원;유지상
    • 대한전자공학회논문지SP
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    • 제39권4호
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    • pp.361-369
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    • 2002
  • 제한된 구역내의 고정(static)된 감시 카메라를 통해 입력된 영상 데이터에 대해 움직임이 있는 물체를 검출하기 위해서는 주위 잡음(noise)에 대한 민감성(sensitivity)과 상황변화에 대해 대처할 수 있는 강인한 알고리즘이 요구된다. 본 논문에서는 이러한 잡음이나 갑작스런 상황의 변화에 적절히 대응하여 움직임 물체를 추출하고 추적하는 효율적인 알고리즘을 제안한다. 초기 배경 모델(background model) 영상에 의해서 입력되는 영상 내에 이동 물체가 존재할 경우 각 화소의 주변의 변화를 고려하여 움직임 영역을 검출하였다. 움직임 영역의 화소들의 잡음 제거를 위해 형태학적 필터(morphological filter)를 사용하였고, 8-연결 성분 표시(connected component labeling)에 의해 개별적인 물체의 움직임을 검출하였다. 마지막으로 다양한 환경과 모델에 따른 실험결과와 통계적인 분석을 제시하였다.