• 제목/요약/키워드: Technology Principle

검색결과 2,179건 처리시간 0.024초

Operation Principle and Topology Structures of Axial Flux-Switching Hybrid Excitation Synchronous Machine

  • Liu, Xiping;Wang, Chen;Zheng, Aihua
    • Journal of international Conference on Electrical Machines and Systems
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    • 제1권3호
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    • pp.312-319
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    • 2012
  • The operation principle of an axial flux-switching hybrid excitation synchronous machine (AFHESM) is analyzed and its topology structures are proposed in this paper. After some comprehensive analysis of the operation principle to axial flux electrical machine, flux-switching electrical machine and hybrid excitation electrical machine, the operation principle of AFHESM is given. Combined with some typical topological structures of hybrid excitation electrical machine, some possible topological structures are proposed and some comprehensive comparisons are carried out. The analysis results show that the stator-separated AFHESM has some advantages such as less AM turns, less impact on the demagnetization of PM, less magnetic flux-leakage and higher efficiency compared to other topologies.

OBSERVABILITY-IN-DEPTH: AN ESSENTIAL COMPLEMENT TO THE DEFENSE-IN-DEPTH SAFETY STRATEGY IN THE NUCLEAR INDUSTRY

  • Favaro, Francesca M.;Saleh, Joseph H.
    • Nuclear Engineering and Technology
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    • 제46권6호
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    • pp.803-816
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    • 2014
  • Defense-in-depth is a fundamental safety principle for the design and operation of nuclear power plants. Despite its general appeal, defense-in-depth is not without its drawbacks, which include its potential for concealing the occurrence of hazardous states in a system, and more generally rendering the latter more opaque for its operators and managers, thus resulting in safety blind spots. This in turn translates into a shrinking of the time window available for operators to identify an unfolding hazardous condition or situation and intervene to abate it. To prevent this drawback from materializing, we propose in this work a novel safety principle termed "observability-in-depth". We characterize it as the set of provisions technical, operational, and organizational designed to enable the monitoring and identification of emerging hazardous conditions and accident pathogens in real-time and over different time-scales. Observability-in-depth also requires the monitoring of conditions of all safety barriers that implement defense-in-depth; and in so doing it supports sensemaking of identified hazardous conditions, and the understanding of potential accident sequences that might follow (how they can propagate). Observability-in-depth is thus an information-centric principle, and its importance in accident prevention is in the value of the information it provides and actions or safety interventions it spurs. We examine several "event reports" from the U.S. Nuclear Regulatory Commission database, which illustrate specific instances of violation of the observability-in-depth safety principle and the consequences that followed (e.g., unmonitored releases and loss of containments). We also revisit the Three Mile Island accident in light of the proposed principle, and identify causes and consequences of the lack of observability-in-depth related to this accident sequence. We illustrate both the benefits of adopting the observability-in-depth safety principle and the adverse consequences when this principle is violated or not implemented. This work constitutes a first step in the development of the observability-in-depth safety principle, and we hope this effort invites other researchers and safety professionals to further explore and develop this principle and its implementation.

사전주의의 원칙은 비과학적인가?: 위험 분석과의 논쟁을 통해 본 사전주의 원칙의 '합리성' (Is the Precautionary Principle Unscientific?: 'Rationality' of the Precautionary Principle and its Conflicts with Risk Analysis Framework)

  • 하대청
    • 과학기술학연구
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    • 제10권2호
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    • pp.143-174
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    • 2010
  • 과학적 불확실성이 존재하는 상황에서 위험에 대응하는 규제 정책의 정당성을 어떻게 확보할 수 있을까? 이런 중요한 물음과 관련해 70년대 이후 유럽을 중심으로 사전주의의 원칙이 하나의 대안으로 부상해왔고 국제 환경법 분야에서는 주요 원리로 인정받아왔다. 하지만 이 원칙은 그 정의의 모호함 때문에 위험분석 옹호자들로부터 다양한 비판을 받아왔다. 이 논문은 이런 여러 비판들의 적실성과 부당함을 함께 평가하면서 사전주의의 원칙의 정교화작업을 시도할 것이다. 그리고 이런 작업을 통해 얻은 결과를 위험 거버넌스 중 과학적 영역으로 흔히 인정받는 위험평가에 적용해봄으로써 이 원칙의 정책적 활용 가능성을 탐색해볼 것이다. 특히, 사전주의의 원칙은 단지 도덕적 태도이거나 정치적 입장일 뿐이라는 일부 시각을 반박하면서 이 원칙이 실제 과학적 활동 속에서 충분히 적용가능한 실제적 원리임을 강조할 것이다.

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자력팽창 및 아크 회전에 의한 배전급 $SF_6$ 복합소호부 개발 연구 (Investigation on $SF_6$ Hybrid Interrupter using Thermal Expansion and Arc Rotation Principle)

  • 이방욱;손종만;강종성;최원준;김영근;서정민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 B
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    • pp.919-921
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    • 2000
  • This paper considers the research of the hybrid interrupter which adopts both rotating arc and thermal expansion technology. The operating principle of this device depends on rapid arc rotation due to the magnetic field created by the fault current through a coil which is mounted on contacts and also relies on the principle of thermal expansion created by arc energy in extinguishing chamber and finally causes pressure rise in expansion volume. In this research, the principle of the interrupting techniques are given and experimental results of hybrid interrupter which is developed by new technology is introduced.

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A Study on the Improvement for Problems of ICT-related laws system in Korea

  • Lee, Hie-Houn
    • International Journal of Advanced Culture Technology
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    • 제7권2호
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    • pp.7-12
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    • 2019
  • Korea's laws regarding ICT must follow the Void for vagueness doctrine, the Principle of forbidden general delegation, the Principle of justification of system and the Principle of balancing test in the Constitution. The Act for the Promotion and Convergence and so on of Information and Communication in the Future should be improved as follows. It is desirable to improve the part where the principle of system justification of the Constitution is problematic in relation to existing laws. It is desirable to improve the ICT's policies on industry and convergence technologies so that they are well balanced between promotion and regulation of ICT's industries. It is desirable to improve the information service policy and legislative makeup relationship between various government agencies related to ICT. It is therefore desirable to improve the institutional complement to the post-regulatory framework for the protection of users of ICT in the future. It is desirable to create a device to replace the functions of the Information Service Budget Council in the special law of ICT.

A Study on the Convergency Property of the Auxiliary Problem Principle

  • Kim, Balho-H.
    • Journal of Electrical Engineering and Technology
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    • 제1권4호
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    • pp.455-460
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    • 2006
  • This paper presents the convergency property of the Auxiliary Problem Principle when it is applied to large-scale Optimal Power Flow problems with Distributed or Parallel computation features. The key features and factors affecting the convergence ratio and solution stability of APP are also analyzed.

$SF_6$ 가스를 이용한 배전급 RMU용 소호부 개발 (Development of Medium Voltage $SF_6$ Interrupter for RMU)

  • 이방욱;손종만;서정민;최중웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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    • pp.301-304
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    • 2001
  • This paper considers the research of the hybrid interrupter which adopts both rotating arc and thermal expansion technology. The operating principle of this device defends on rapid arc rotation due to the magnetic field created by the fault current through a coil which is mounted on contacts and also relies on the principle of thermal expansion created by arc energy in extinguishing chamber and finally causes pressure rise in expansion volume. In this research, the principle of the interrupting techniques are given and experimental results of hybrid interrupter which is developed by new technology is introduced.

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모델링 기반의 경영정보학 교육 방안 (A Modeling Based MIS Education)

  • 강신철
    • Journal of Information Technology Applications and Management
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    • 제19권4호
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    • pp.153-169
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    • 2012
  • In the rapidly changing field of Management Information Systems, the definition and educational programs must be continually reevaluated and revised. A study was conducted to find a way to which the modeling principle is applied for redefining the identity of Management Information Systems as an independent academic field and to develop a plausible MIS curriculum based on the modeling principle. Previous researches on the MIS frameworks, knowledge and technology requirements for IS professionals, and standard MIS curriculums were reviewed thoroughly. For this study, the Kantian cognitive model was adopted as a basis of modeling principle. The result shows that modeling ability has been the core competence of IS people in the field of MIS. The applicability of a modeling principle is also verified in establishing the identity of MIS and developing a normative MIS curriculum. For the MIS field to thrive as an independent academic field and research discipline, it is believed to be imperative for the discipline to have a unique educational goals distinguished from both other management areas, and sub-fields of computer science.

GMO 안전성평가제도의 고찰 (Need for Reinforcement of Safety Assessment on Genetically Modified Organisms)

  • 김은진;최동근
    • 한국유기농업학회지
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    • 제14권2호
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    • pp.139-157
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    • 2006
  • Biotechnology has reached the level of giving birth to new forms of life and with this is a growing controversy in the conflict between science and ethics. Especially, GMOs are closely linked to the food products we consume and thus, the majority of the public shows a very sensitive reaction to the safety of GMO food products. Many perspectives arose surrounding the issues of safety on the human body and the ecology. This outlines diverse structural mechanisms to be set up to ensure safety such as risk assessment, risk management etc. Despite the precautionary principle guaranteed in many ways, the problem arises whether and how this principle can be taken in the safety assessment. GMOs due to its uniqueness do not end with just the possession of the technology involved but must also be considered with the prerequisite that they could be cultured again. Therefore the reinforcement of safety assessment system is necessary. That is, the reinforcement of risk assessment including field tests, the consideration of socio-economic effects, the coordinated system of relevant authorities, the development of technology for safety assessment.

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