• 제목/요약/키워드: Hamiltonian approach

검색결과 33건 처리시간 0.029초

Study of complex nonlinear vibrations by means of accurate analytical approach

  • Bayat, Mahmoud;Pakar, Iman;Bayat, Mahdi
    • Steel and Composite Structures
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    • 제17권5호
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    • pp.721-734
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    • 2014
  • In the current study, we consider a new class of analytical periodic solution for free nonlinear vibration of mechanical systems. Hamiltonian approach is applied to analyze nonlinear problems which occur in dynamics. The proposed method doesn't have the limitations of the classical methods and leads us to a high accurate solution by only one iteration. Two well known examples are studied to show the convenience and effectiveness of this approach. Runge-Kutta's algorithm is also applied and the results of it are compared with the Hamiltonian approach. High accuracy of the proposed approach reveals that the Hamiltonian approach can be very useful for other nonlinear practical problems in engineering.

Accurate semi-analytical solution for nonlinear vibration of conservative mechanical problems

  • Bayat, Mahmoud;Pakar, Iman
    • Structural Engineering and Mechanics
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    • 제61권5호
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    • pp.657-661
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    • 2017
  • In this paper, it has been tried to propose a new semi analytical approach for solving nonlinear vibration of conservative systems. Hamiltonian approach is presented and applied to high nonlinear vibration systems. Hamiltonian approach leads us to high accurate solution using only one iteration. The method doesn't need any small perturbation and sufficiently accurate to both linear and nonlinear problems in engineering. The results are compared with numerical solution using Runge-Kutta-algorithm. The procedure of numerical solution are presented in detail. Hamiltonian approach could be simply apply to other powerfully non-natural oscillations and it could be found widely feasible in engineering and science.

Analytical study on non-natural vibration equations

  • Bayat, Mahmoud;Pakar, Iman
    • Steel and Composite Structures
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    • 제24권6호
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    • pp.671-677
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    • 2017
  • In this paper, two powerful analytical methods called Variational Approach (VA) and Hamiltonian Approach (HA) are used to solve high nonlinear non-Natural vibration problems. The presented approaches are works well for the whole range of amplitude of the oscillator. The first iteration of the approaches leads us to high accurate solution. Numerical results are also presented by using Runge-Kutta's [RK] algorithm. The full comparison between the presented approaches and the numerical ones are shown in figures. The effects of important parameters on the response of nonlinear behavior of the systems are studied completely. Finally, the results show that the Variational Approach and Hamiltonian approach are strong enough to prepare easy analytical solutions.

PERIODIC SOLUTIONS FOR THE NONLINEAR HAMILTONIAN SYSTEMS

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
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    • 제17권3호
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    • pp.331-340
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    • 2009
  • We show the existence of nonconstant periodic solution for the nonlinear Hamiltonian systems with some nonlinearity. We approach the variational method. We use the critical point theory and the variational linking theory for strongly indefinite functional.

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An accurate novel method for solving nonlinear mechanical systems

  • Bayat, Mahdi;Pakar, Iman;Bayat, Mahmoud
    • Structural Engineering and Mechanics
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    • 제51권3호
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    • pp.519-530
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    • 2014
  • This paper attempts to investigate the nonlinear dynamic analysis of strong nonlinear problems by proposing a new analytical method called Hamiltonian Approach (HA). Two different cases are studied to show the accuracy and efficiency of the method. This approach prepares us to obtain the nonlinear frequency of the nonlinear systems with the first order of the solution with a high accuracy. Finally, to verify the results we present some comparisons between the results of Hamiltonian approach and numerical solutions using Runge-Kutta's [RK] algorithm. This approach has a powerful concept and the high accuracy, so it can be apply to any conservative nonlinear problems without any limitations.

Accurate analytical solution for nonlinear free vibration of beams

  • Bayat, M.;Pakar, I.
    • Structural Engineering and Mechanics
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    • 제43권3호
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    • pp.337-347
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    • 2012
  • In this study, Hamiltonian Approach (HA) is applied to analysis the nonlinear free vibration of beams. Two well-known examples are illustrated to show the efficiency of this method. One of them deals with the Nonlinear vibration of an electrostatically actuated microbeam and the other is the nonlinear vibrations of tapered beams. This new approach prepares us to achieve the beam's natural frequencies and mode shapes easily and a rapidly convergent sequence is obtained during the solution. The effects of the small parameters on the frequency of the beams are discussed. Some comparisons are conducted between the results obtained by the Hamiltonian Approach (HA) and numerical solutions using to illustrate the effectiveness and convenience of the proposed methods.

Energy based approach for solving conservative nonlinear systems

  • Bayat, M.;Pakar, I.;Cao, M.S.
    • Earthquakes and Structures
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    • 제13권2호
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    • pp.131-136
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    • 2017
  • This paper concerns two new analytical approaches for solving high nonlinear vibration equations. Energy Balance method and Hamiltonian Approach are presented and successfully applied for nonlinear vibration equations. In these approaches, there is no need to use small parameters to solve and only with one iteration, high accurate results are reached. Numerical procedures are also presented to compare the results of analytical and numerical ones. It has been established that, the proposed approaches are in good agreement with numerical solutions.

해밀톤역학을 이용한 충격현상의 모델링 (Hamilton's Equations for Modeling of Impact Dynamics)

  • 구자춘
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 I
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    • pp.85-89
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    • 2001
  • Hamiltonian modeling approach has been extensively adopted for rigid body dynamics whereas its usage for deforming flexible continuum dynamics has been limited. A set of Hamilton's equations for flexible body motion with finite deformation has been derived and applied for a nonlinear impact problem.

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Structural health monitoring through nonlinear frequency-based approaches for conservative vibratory systems

  • Bayat, M.;Pakar, I.;Ahmadi, H.R.;Cao, M.;Alavi, A.H.
    • Structural Engineering and Mechanics
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    • 제73권3호
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    • pp.331-337
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    • 2020
  • This paper proposes a new approximate analytical solution for highly nonlinear vibration of mechanical systems called Hamiltonian Approach (HA) that can be widely use for structural health monitoring systems. The complete procedure of the HA approach is studied, and the precise application of the presented approach is surveyed by two familiar nonlinear partial differential problems. The nonlinear frequency of the considered systems is obtained. The results of the HA are verified with the numerical solution using Runge-Kutta's [RK] algorithm. It is established the only one iteration of the HA leads us to the high accurateness of the solution.

Band Structure Analysis of Strained Quantum Wire Arrays

  • Yi, Jong-Chang;Ji, Jeong-Beom
    • Journal of the Optical Society of Korea
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    • 제7권1호
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    • pp.7-12
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    • 2003
  • A numerical approach for the analysis of quantum wire structures has been presented using a finite-element method which includes the strain analysis and the band analysis of the Luttinger-Kohn Hamiltonian with the deformation potential. A systematic implementation of the multiband Hamiltonian in the finite-element scheme is outlined and the corresponding variational functional is derived for arbitrarily shaped strained quantum wire arrays. This method is then applied to calculate the band structures of strained quantum wire arrays.