• 제목/요약/키워드: equivalent systems

검색결과 1,277건 처리시간 0.027초

자기등가회로법에 의한 유도전동기 과도상태해석 (An analysis of transient state for induction motor by using the magnetic equivalent circuit method)

  • 정종호;이은웅;조현길;김준호;이화수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.18-20
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    • 2002
  • In this paper, the construction elements of the induction motor was represented by the magnetic tube. The magnetic tube is basis of the magnetic equivalent circuit. The magnetic equivalent circuit method is convenient of complicated analysis of the transient state of the induction motor. Because the method is restriction on only one direction of magnetic flux. Air gap magnetomotive force was calculated by magnetic equivalent circuit method. Starting transient torque and phase current of the induction motor was confirmed by the theoretical calculation and the experiments.

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A Study on Determination of Shear Center of Beam with Arbitrary Cross Section

  • Oh, Teak-Yul;Byun, Chang-Hwan;Known, Young-Ha
    • International Journal of Precision Engineering and Manufacturing
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    • 제4권4호
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    • pp.39-44
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    • 2003
  • It is important to find the shear center of beam with arbitrary cross-section in structures. In this study, it is introduced to determine the shear center that gets the equivalent stiffness matrix representing arbitrary cross section of beam and applies concepts of equivalent energy. This method shows the results of applying on examples that the exact and approximate solution of open and cross section of beam is known. The shear center of composite rotor blade by the experiment and by the suggested method was compared in this study.

Discretization Behaviors of Equivalent Control Based Sliding-Mode Systems

  • Son, Sung-Han;Cho, Byung-Sun;Han, So-Hee;Park, Kang-Bak
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.425-428
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    • 2004
  • In this paper, we study the discretization behaviors of the equivalent control based sliding-mode control (SMC) systems. The investigation is carried out via studying the second order linear system and some interesting dynamic properties are explored. Especially, according to the variation of system parameters, the inherent dynamical behavior of the trajectories within some specified boundaries are studied. From this result, the boundaries of system state using symbolic dynamics approach are first proposed. Simulations are presented to verify the theoretical results.

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비선형 시스템에 대한 T-S 퍼지 모델 구성 (Construction of T-S Fuzzy Model for Nonlinear Systems)

  • 정은태;권성하;이갑래
    • 제어로봇시스템학회논문지
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    • 제8권11호
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    • pp.941-947
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    • 2002
  • Two methods of constructing T-S fuzzy model which is equivalent to a given nonlinear system are presented. The first method is to obtain an equivalent T-S fuzzy model by using the sum of linearly independent scalar functions with constant real matrix coefficients. The sum of products of linearly independent scalar functions is used in the second method. The former method is to formulate the procedures of T-S fuzzy modeling dealt in many examples of previous publications; the latter is a new method. By comparing the number of linearly independent functions used in the two methods, we can easily find out which method makes fewer rules than the other. The nonlinear dynamics of an inverted Pendulum on a cart is used as an equivalent T-5 fuzzy modeling example.

등가 물성 평가를 이용한 골판지의 물성치 (The Mechanical Properties of Corrugated Cardboard using Equivalent Evaluation)

  • 권경영;정종윤
    • 산업경영시스템학회지
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    • 제37권1호
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    • pp.157-164
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    • 2014
  • The usage of corrugated cardboard for packing material is increasing in these days because it is light and easy to manufacture packing boxes. However, the structure analysis of packing boxes, made of cardboard, is not well carried. The reason can be deduced that its mechanical properties for structure analysis are not well known. The cardboards are made different shapes with various types of raw materials that are paper-based compound. In addition, the cardboards are considered to be orthotropic material. This research finds mechanical properties of triple layered cardboard which is composed of outer liner and inner liner. The moduli of elasticity and of shear for liners are found from tension test and T-Peel test. The mechanical properties of the cardboard are calculated using the super position method and equivalent evaluation method.

Equivalent linear and bounding analyses of bilinear hysteretic isolation systems

  • Wang, Shiang-Jung;Lee, Hsueh-Wen;Yu, Chung-Han;Yang, Cho-Yen;Lin, Wang-Chuen
    • Earthquakes and Structures
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    • 제19권5호
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    • pp.395-409
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    • 2020
  • With verifications through many relevant researches in the past few decades, adopting the equivalent lateral force procedure for designing seismically isolated structures as a preliminary or even final design approach has become considerably mature and publicly acceptable, especially for seismic isolation systems that mechanically exhibit bilinear hysteretic behavior. During the design procedure, in addition to a given seismic demand, structural designers still need to previously determine three parameters, such as mechanical properties of seismic isolation systems or design parameters and performance indices of seismically isolated structures. However, an arbitrary or improper selection of given parameters might cause diverse or even unacceptable design results, thus troubling structural designers very much. In this study, first, based on the criterion that at least either two design parameters or two performance indices of seismically isolated structures are decided previously, the rationality and applicability of design results obtained from different conditions are examined. Moreover, to consider variations of design parameters of seismically isolated structures attributed to uncertainties of mechanical properties of seismic isolation systems, one of the conditions is adopted to perform bounding analysis for seismic isolation design. The analysis results indicate that with a reasonable equivalent damping ratio designed, considering a specific variation for two design parameters (the effective stiffness and equivalent damping ratio) could present more conservative bounding design results (in terms of isolation displacement and acceleration transmissibility) than considering the same variation but for two mechanical properties (the characteristic strength and post-yield stiffness).

조합하중시의 플랫 플레이트 슬래브 시스템에 대한 수정된 등가골조 모델 (A Modified Equivalent Frame Model for Flat Plate Slabs Under Combined Lateral and Gravity Loads)

  • 오승용;박영미;한상환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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    • pp.369-372
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    • 2006
  • Flat plate slab systems have been commonly used as a gravity force resisting systems, which should be constructed with lateral force resisting systems such as shear walls and moment resisting frame. ACI 318(2005) allows the Direct design method, the equivalent frame method (ACI-EFM) under gravity loads and the finite-element models, effective beam width models and equivalent frame models under lateral loads. ACI-EFM can be used for gravity loads as well as lateral loads analysis. But the method may not predict the behavior of flat plate slabs under lateral loads. Thus Previous study developed a Modified equivalent frame method(Modified-EFM) which could give more precise answer for flat plate slab under lateral loads. This study is to verified the accuracy of a Modified-EFM under combined lateral and gravity loads. The accuracy of this model is verified by comparing the results using the Modified-EFM with the results of finite element analysis. For this purpose, 7 story building is considered. The analysis results of other existing models are included. The analysis results show that Modified-EFM produces comparable drift and slab internal moments with those obtained from finite element analysis.

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Verilog UDP Library의 등가 게이트수준 모델 생성 (Generation of Gate-level Models Equivalent to Verilog UDP Library)

  • 박경준;민형복
    • 전자공학회논문지SC
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    • 제40권1호
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    • pp.30-38
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    • 2003
  • Verilog HDL의 UDP(User Defined Primitive) 라이브러리는 디지털 회로 설계 과정에서 시뮬레이션을 위해 사용된다. 그러나 합성이 되지 않는 특성으로 인해 이와 등가의 게이트수준 라이브러리를 따로 만드는 데에 많은 시간과 노력이 소요된다. 등가의 게이트수준 모델이 존재하지 않을 경우 이는 테스트 과정에서 고장 검출율을 낮추는 요인이 되므로 등가 게이트수준 모델 생성은 필수적이며 이의 자동화가 필요하다. 이를 위해 매우 복잡한 알고리즘이 발표되기는 했지만 Verilog UDP library의 특성상 보다 더 간단한 알고리즘으로 구현이 가능하다. 알고리즘이 간략해짐에 따라 이를 구현하는 데에 걸리는 시간과 노력이 절약되고 프로그램 실행시간도 크게 줄일 수 있다.

Vault macro-element with equivalent trusses in global seismic analyses

  • Giresini, Linda;Sassu, Mauro;Butenweg, Christoph;Alecci, Valerio;De Stefano, Mario
    • Earthquakes and Structures
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    • 제12권4호
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    • pp.409-423
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    • 2017
  • This paper proposes a quick and simplified method to describe masonry vaults in global seismic analyses of buildings. An equivalent macro-element constituted by a set of six trusses, two for each transverse, longitudinal and diagonal direction, is introduced. The equivalent trusses, whose stiffness is calculated by fully modeled vaults of different geometry, mechanical properties and boundary conditions, simulate the vault in both global analysis and local analysis, such as kinematic or rocking approaches. A parametric study was carried out to investigate the influence of geometrical characteristics and mechanical features on the equivalent stiffness values. The method was numerically validated by performing modal and transient analysis on a three naves-church in the elastic range. Vibration modes and displacement time-histories were compared showing satisfying agreement between the complete and the simplified models. This procedure is particularly useful in engineering practice because it allows to assess, in a simplified way, the effectiveness of strengthening interventions for reducing horizontal relative displacements between vault supports.

Hybrid State Space Self-Tuning Fuzzy Controller with Dual-Rate Sampling

  • Kwon, Oh-Kook;Joo, Young-Hoon;Park, Jin-Bae;L. S. Shieh
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.244-249
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    • 1998
  • In this paper, the hybrid state space self-tuning control technique Is studied within the framework of fuzzy systems and dual-rate sampling control theory. We show that fuzzy modeling techniques can be used to formulate chaotic dynamical systems. Then, we develop the hybrid state space self-tuning fuzzy control techniques with dual-rate sampling for digital control of chaotic systems. An equivalent fast-rate discrete-time state-space model of the continuous-time system is constructed by using fuzzy inference systems. To obtain the continuous-time optimal state feedback gains, the constructed discrete-time fuzzy system is converted into a continuous-time system. The developed optimal continuous-time control law is then convened into an equivalent slow-rate digital control law using the proposed digital redesign method. The proposed technique enables us to systematically and effective]y carry out framework for modeling and control of chaotic systems. The proposed method has been successfully applied for controlling the chaotic trajectories of Chua's circuit.

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