• Title/Summary/Keyword: System Transition

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Quantum Transition Properties of Quasi-Two Dimensional Si System in Electron Deformation Potential Phonon Interacting (전자 포텐셜 변형과 포논 상호작용에 의한 준 이차원 Si 구조의 전도 현상 해석)

  • Lee, Su-Ho;Kim, Young-Mun;Kim, Hai-Jai;Joo, Seok-Min
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.66 no.3
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    • pp.129-134
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    • 2017
  • We investigated theoretically the quantum optical transition properties of Si, in quasi 2-Dimensinal Landau splitting system, based on quantum transport theory. We apply the quantum transport theory (QTR) to the system in the confinement of electrons by square well confinement potential under linearly polarized oscillating field. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS). In order to analyze the quantum transition, we compare the temperature and the magnetic field dependencies of the QTLW and the QTLS on four transition processes, namely, the intra-leval transition process, the inter-leval transition process, the phonon emission transition process and the phonon absorption transition process.

Transition as a Theory and Practice: Transition Studies and Policies in Netherlands (이론과 실천으로서의 전환 : 네덜란드의 전환이론과 전환정책)

  • Jung, Byung Kul
    • Journal of Science and Technology Studies
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    • v.15 no.1
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    • pp.109-143
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    • 2015
  • For continuous and successful innovation, changes in innovation system are required and have been magnified as a new controversy. With high public interest in changes of innovation system, Transition theory and policy in Netherlands are now attracting attentions of many researchers and policymakers. Transition policy in Netherlands is distinguished from existing policies for fundamental system change in that take remarkably different views and methods. Typical examples of transition in Netherlands are such as sustainable energy transition, biodiversity and natural resource transition, sustainable agriculture transition, and sustainable transportation. Transitions in Netherlands are still in the early stage of it but several positive effects are witnessing. However some problems - linking theory and practice, ambiguity of transition concept, linking long-term vision and short-term, resistance of existing regime, implementation problem, diffusion of support, etc.- to be tackled are still remaining. In spite of those problems, many lessons can be drawn from them. To guide structural changes in innovation system into the right path and cope with lock-in problem by existing system and regime, we need to learn from Transition theory and policy in Netherlands.

Transition Rates in a Bistable System Driven by Singular External Forces

  • Cheol-Ju Kim;Dong Jae Lee
    • Bulletin of the Korean Chemical Society
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    • v.14 no.1
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    • pp.95-100
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    • 1993
  • A noise-induced transition is presented for a bistable system subjected to a multiplicative random force, which is singular at the unstable state. The stationary probability distribution is obtained from the Fokker-Planck equation and the effects of the singularity is analyzed. On the basis of noise-induced phase transition with Gaussian white noise, the relaxation time and the transition rate of the system are evaluated up to the first order correction of D. In the parameter region v < l, the transition rates decrease as the exponent v goes to 1 and as the coefficient of the linear term of the kinetic equation increases.

The Designed and Simplified Markov Models for Systems Based on Kronecker Algebra

  • Oh, Chung Hwan
    • Journal of Korean Society for Quality Management
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    • v.20 no.1
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    • pp.11-21
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    • 1992
  • The Purpose of this paper contribute to design the multistate Markov process for the reliability of a system when the transition-rates of each unit depend on the current state of the system. The system transition-rate matrix has the form of the kronecker sum of transition rate matrices for the units, is analyzed and investigated. As a result, the system which has the state-dependent units is detaily analyzed and introduced by the approach of an algorithm for the system transition-rate matrix based on the kronecker algebra.

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Eigenvalue Analysis of Power Systems with Non-Continuous Operating Elements by the RCF Method : Modeling of the State Transition Equations (불연속 동작특성을 갖는 전력계통의 RCF법을 사용한 고유치 해석 : 상태천이 방정식으로의 모델링)

  • Kim Deok Young
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.2
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    • pp.67-72
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    • 2005
  • In conventional small signal stability analysis, system is assumed to be invariant and the state space equations are used to calculate the eigenvalues of state matrix. However, when a system contains switching elements such as FACTS devices, it becomes non-continuous system. In this case, a mathematically rigorous approach to system small signal stability analysis is by means of eigenvalue analysis of the system periodic transition matrix based on discrete system analysis method. In this paper, RCF(Resistive Companion Form) method is used to analyse small signal stability of a non-continuous system including switching elements. Applying the RCF method to the differential and integral equations of power system, generator, controllers and FACTS devices including switching elements should be modeled in the form of state transition equations. From this state transition matrix eigenvalues which are mapped to unit circle can be calculated.

Modeling of the State Transition Equations of Power Systems with Non-continuously Operating Elements by the RCF Method

  • Kim, Deok-Young
    • KIEE International Transactions on Power Engineering
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    • v.5A no.4
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    • pp.344-349
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    • 2005
  • In conventional small signal stability analysis, the system is assumed to be invariant and the state space equations are used to calculate the eigenvalues of the state matrix. However, when a system contains switching elements such as FACTS equipments, it becomes a non-continuous system. In this case, a mathematically rigorous approach to system small signal stability analysis is performed by means of eigenvalue analysis of the system's periodic transition matrix based on the discrete system analysis method. In this paper, the RCF (Resistive Companion Form) method is used to analyze the small signal stability of a non-continuous system including switching elements. Applying the RCF method to the differential and integral equations of the power system, generator, controllers and FACTS equipments including switching devices should be modeled in the form of state transition equations. From this state transition matrix, eigenvalues that are mapped into unit circles can be computed precisely.

Qantum Transition properties of Si in Electron Deformation Potential Phonon Interacting Qusi Two Dimensional System (준 2차원 시스템에서 전자 변위 포텐셜 상호 작용에 의한 Si의 양자 전이 특성)

  • Joo, Seok-Min;Cho, Hyun-Chul;Lee, Su-Ho
    • Journal of IKEEE
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    • v.23 no.2
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    • pp.502-507
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    • 2019
  • We investigated theoretically the quantum optical transition properties of qusi 2-Dinensinal Landau splitting system, in Si. We apply the Quantum Transport theory (QTR) to the system in the confinement of electrons by square well confinement potential. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS). In order to analyze the quantum transition, we compare the temperature and the magnetic field dependencies of the QTLW and the QTLS on two transition processes, namely, the phonon emission transition process and the phonon absorption transition process. Through the analysis of this work, we found the increasing properties of QTLW and QTLS of Si with the temperature and the magnetic fields. We also found the dominant scattering processes are the phonon emission transition process.

Socio-Technological System Transition and Innovation Activities of Firms (사회-기술 시스템 전환과 기업 혁신활동)

  • Hwang, Hye-Ran;Song, Wi-Chin
    • Journal of Technology Innovation
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    • v.22 no.4
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    • pp.57-88
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    • 2014
  • The 'Grand Challenge' in the global level raises fundamental questions on the role of private firm as a profit maximizer. From the new perspective, firms are recognized as a social entity with social and environmental responsibility. Particularly, the importance of transition-orineted firms, which pursue an objective of socio-technological system transition, have increased. These environmental changes request a new understanding on the identification of firms and the evolution of sustainable business model from the technological innovation perspectives. This paper aims on the new understanding on the motivation of firms who participated on the sustainable system transition and the proposal of 'transition-oriented firms' concept. Based on literature survey, this paper reviews the role of firms in the process of socio-technological system transition, the cases of transition-oriented firm, the types of sustainable business models and their strategies.

Phase Transition and Approximated Integral Equation for Radial Distribution Function

  • Yoon, Byoung-Jip;Jhon, Mu-Shik
    • Bulletin of the Korean Chemical Society
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    • v.7 no.1
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    • pp.20-23
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    • 1986
  • A reduced condition for liquid-gas phase transition from the singularity of compressibility is derived using diagrammatic approach and is examined in the hard sphere system. The condition turns out that the Percus-Yevick and the Hyper-Netted-Chain approximation never conceive the idea of phase transition, and explains that the liquid-gas transition does not exist in hard sphere system. The solid-fluid transition is considered on the viewpoint of correlation function and diagrammatic analysis.

The Magnetic Field Dependence of the Confinement Potential due to the Interaction of Electron and Piezoelectric Phonon in GaAs Semiconducting Materials (구속 포텐셜의 전자-압전 포논 상호 작용에 따른 GaAs의 자기장 의존 특성)

  • Lee, Su-Ho;Kim, Hai-Jai;Joo, Seok-Min
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.67 no.3
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    • pp.149-154
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    • 2018
  • We consider the system is subject to the linearly polarized oscillatory external field. We study the optical quantum transition Line shapes(QTLS) which show the absorption power and the quantum transition line widths(QTLW) of electron-piezoelectric phonon interacting system. We analyze the magnetic field dependence of the QTLS and the QTLW in various cases. In order to analysis the quantum transition, we compare the magnetic field dependence of the QTLW and the QTLS of two transition process, the intra-Landau level transition process and the inter-Landau level transition process.