• 제목/요약/키워드: Once through

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우리나라 산업용 보일러의 효율적 운용에 관한 연구 (A Study on Efficient Operations of Industrial Boilers in Korea)

  • 조흥곤
    • 기술사
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    • 제35권4호
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    • pp.68-73
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    • 2002
  • Almost every industrial plant or building has their own boiler systems, so boilers are often called "kinds of social infrastructures"In Korea, We have many indistinct problems on efficient operations of industrial boiler systems. In this paper, to elevate thermal operation efficiency and to diminish air pollutions of the boilers, especially in urban area, at present, "The muliple installation systems of small type once through boiler(gas fired)" are suggested.

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전력용 변압기 내부고장시 전압-차전류의 변화에 관한 연구 (Transition of voltage-differential current under internal fault on power transformer)

  • 박재세
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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    • pp.92-95
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    • 2004
  • Power transformer is an important apparatus in transforming and delivering the power in a power system. It shows less accident ratio than other system apparatus, but once the accident occurs, it causes long-term operation stoppage and economic loss. It brings high bad spillover effects. Therefore, the role of protective relaying, which is to prevent internal fault a power transformer is highly important. This study proposed advanced algorithm that can clearly determine internal fault of the power transformer and magnetizing inrush, through numerical analysis by using the terminal voltage and input output current.

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연속법에 의한 판구조 고유진동수의 민감도 해석 (Eigenvalue design sensivity analysis of structure using continuum method)

  • 이재환;장강석;신민용
    • 한국해양공학회지
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    • 제11권1호
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    • pp.3-9
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    • 1997
  • In this paper, design sensivity of plate natural frequency is computed for thickness design variables. Once the variational equation is derived from Lagrange quation using the virtual displacement, governing energy bilinear form is obtained and sensivity equation is formulated through the first variation. Natural frequency is obtained using the commercial FEM code and the accuracy of sensivity is verified by finite difference. The accuracy of natural frequency and sensivity improves for the fine mesh model.

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현가계 설계인자 계산을 위한 탄성기구학 해석 (Elastokinematic Analysis for Calculating Suspension Design Parameters)

  • 강주석;윤중락;배상우;이장무;탁태오
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.887-890
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    • 1996
  • In this study, based on the assumption that the displacements of suspension systems under the external forces are very small, a linear form of elastokinametic equations in terms of infinitesimal displacements and joint reaction forces are derived. The equations can be applied to any form of suspensions once the type of kinematic joints and bushings are identified. The validity of the method is proved through the comparison of the results from the more complex solution offered by ADAMS

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저층방류 해석을 위한 수치모의

  • 김철;김대근
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2004년도 분과위원회 연구과업 보고서
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    • pp.93-111
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    • 2004
  • 온수 방류방식의 분류는 냉각수 공급방식별로 냉각수 통과방식(once-through cooling system)과 냉각수 재순환방식(closed-cycle cooling: system)으로 구분된다. 배출구조별 분류는 수표면방류 방식(surface discharge type)과 수중방류 방식(submerged discharge type)으로 구분된다. 국내 외의 연구결과 수중 방류방식이 희석효과가 좋아 환경에 미치는 영향이 작은 것으로 평가되고 있으나, 국내의 발전소에서는 대부분 수표면방류 방식을 채택하고 있다. (중략)

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Modeling of an Once Through Helical Coil Steam Generator of a Superheated Cycle for Sizing Analysis

  • Kim, Yeon-Sik;Sim, Yoon-Sub;Kim, Eui-Kwang
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 추계학술발표회논문집(1)
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    • pp.558-563
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    • 1997
  • A thermal sizing code, named as HSGSA (Helical coil Steam Generator Sizing Analyzer), for a sodium heated helical coil steam generator is developed for KALIMER (Korea Advanced LIquid MEtal Reactor) design. The theoretical modeling of the shell and tube sides is described and relevant correlations are presented. For assessment of HSGSA, a reference plant design case is compared to the calculational outputs from HSGSA simulation.

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운영단계의 소프트웨어 신뢰도에 관한 연구 (A Study on the S/W Reliability during Operational Stage)

  • 최규식;김용경
    • Journal of Information Technology Applications and Management
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    • 제10권4호
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    • pp.185-194
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    • 2003
  • One method to improve S/W quality before releasing after development is to enhance the its reliability, whose direct methodology is to detect and revise the fault through testing. Once the S/W is released because it meets the target reliability, We operational reliability arises. it is obvious the operational reliability different depending on the condition whether it is universal(package) S/W or dedicated S/W. We propose the methodology to calculate operational software reliability of universal and dedicated S/Ws in this paper.

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가압경수로에서 비순환 토륨 핵연료 주기의 적용 타당성 (A Feasibility of Once-Through Thorium Fuel Cycle for PWR)

  • 우일탁;김명현
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 1999년도 추계 학술발표회 논문집
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    • pp.131-136
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    • 1999
  • 토륨은 자연계에서 유일한 동위원소인 Th-232로 존재하며 반감기는 1.4$\times$$10^{10}$년으로 U-238의 4.5$\times$$10^{9}$년에 비하여 약 3배 길고 매장량도 약 3배 많은 것으로 알려져 있다. 토륨은 원자력 초기 개발단계인 1950년대부터 우라늄에 관한 연구와 함께 시작되었지만, 70년대 중반 이후로는 토륨 핵연료 재처리의 어려움과 여러 정치적 이유로 이에 관한 연구가 거의 중단되었다.(중략)

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How Well Did We Know About Our Communication? "Origins of Human Communication"

  • Jung-Woo Son
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제34권1호
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    • pp.57-58
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    • 2023
  • Through accurate observation and the results of experimental studies using great apes, the author tells us exactly what we have not known about human communication. The author persuasively conveys to the reader the grand history of developing from great apes' gestures to human gestures, to human speech. Given that great apes and human gestures were the origin of human voice language, we have once again realized that our language is, after all, an "embodied language."