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This paper presents the numerical methods for the nonlinear simulations of cyclokinetic [Waltz and Zhao Deng (2013)] equations in Fourier harmonics of the gyro-phase. A parallel processed, implicit time advanced, Eulerian (or continuum) code (rCYCLO) is developed. A novel numerical treatment of the magnetic moment velocity space derivative operator guarantees accurate conservation of the incremental entropy. By comparing the cyclokinetic simulations with the corresponding gyrokinetics, we quantitatively test the breakdown of gyrokinetics at high turbulence levels over a range of large relative ion cyclotron frequency ( 10 < Ω ∗ < 100 where Ω ∗ = 1 / ρ ∗ , and ρ ∗ is the relative ion gyroradius). As an important code verification, the rCYCLO gyrokinetic transport recovers cyclokinetic transport at high relative ion cyclotron frequency ( Ω ∗ ⩾ 50 ) and low turbulence levels. In the case of linearly stable ion cyclotron modes, the cyclokinetic transport is lower (not higher) than the gyrokinetic transport at high turbulence levels and low- Ω ∗ values. [ABSTRACT FROM AUTHOR]

Abstract: A numerical procedure is presented in this paper for the two-dimensional, time-harmonic elastodynamic multiple scattering problems for unidirectional fiber-reinforced composites. The proposed procedure is based on the eigenfunction expansion of the displacement potentials and the numerical collocation method to solve the expansion coefficients, and is capable of modeling arbitrary fiber arrangements. To demonstrate the applicability of the procedure, the P and SV wave propagation characteristics in unidirectional fiber-reinforced composites are analyzed for different fiber arrangements and fiber volume fractions. The simulated results are shown to capture the detailed features of the local wave fields in the composites accompanying the mode conversion. From the computed wave fields, the effective phase velocities of the composites are identified as functions of the frequency, and found to be in good agreement with the predictions of a micromechanical model for random composites. The energy transmission spectra of the P and SV waves are also demonstrated, which exhibit the stop-band formation for the composites with regular fiber arrangements. [Copyright &y& Elsevier]

Abstract: The problem of the harmonic sheat oscillations of an elastic strip, coupled to an elastic half-space is considered. Using the method of integral transformations, the problem is reduced to a singular integral equation in the contact stresses in the region where the strip and the half-space are coupled when there are two fixed singularities at points bounding the integration intervals. One of the main results of this paper is the method of solving this equation numerically, taking into account the true singularity of the solution and based on the use of special quadrature formulae for singular integrals. The approximate solution obtained provides the possibility of numerically investigating the effect of the oscillation frequency and the ratio of the elastic constants of the strip and the half-space on the stress distribution in the contact area. [Copyright &y& Elsevier]

Abstract: In this paper, periodic and chaotic behaviors of DC–DC converters under certain parametric conditions are simulated, experimentally verified, and analyzed. Motivated by the work of J.H.B. Deane and D.C. Hamill in 1996, where chaotic phenomena are useful in suppressing electromagnetic interference (EMI) by adjusting the parameters of the DC–DC converter and making it operate in chaos, a chaos-based pulse width modulation (CPWM) is proposed to distribute the harmonics of the DC–DC converters continuously and evenly over a wide frequency range, thereby reducing the EMI. The output waves and spectral properties of the EMI are simulated and analyzed as the carrier frequency or amplitude changes with regard to different chaotic maps. Simulation and experimental results are given to illustrate the effectiveness of the proposed CPWM, which provides a good example of applying chaos theory in engineering practice. [Copyright &y& Elsevier]

Abstract: This paper discusses applications of Somiglina''s identities to the solutions of elasticity problems with spherical boundaries. The components of the boundary displacements and tractions involved in the identities are represented as truncated series of surface spherical harmonics, and all of the integrals involved in the formulae are evaluated analytically. The classical problems of a solid sphere, a spherical cavity, and a perfectly bonded spherical inhomogeneity (an inclusion with the elastic properties different from those of the surrounding material) are solved with the use of Somiglina''s identities. Extensions of the new solutions to more complicated three-dimensional problems with spherical boundaries are discussed. [Copyright &y& Elsevier]

Abstract: Considering the space harmonics caused by the faulted windings, a simulation model of internal faults in salient pole synchronous machines is proposed in this paper. The model is based on the winding function approach, which makes no assumption for sinusoidal symmetrical distribution of the machine windings. A new method of calculation of synchronous machine inductances is presented, in which the space harmonics produced by the windings are readily taken into account. Simulation results for internal faults on the stator windings of a generator at no load and at load are compared with experimental results to verify the accuracy of the proposed model. [Copyright &y& Elsevier]

Global dynamical models of power electronic systems allow to compute their dynamics in a very easy way as they replace the switching behavior of the power electronic converter by a continuous process [F. Labrique, H. Buyse, G. Seguier, R. Bausiere, Les convertisseurs de l’electronique de puissance—Commande et comportement dynamique, vol. 5, Technique et Documentation, Lavoisier, Paris, France, 1998; H. Buyse, D. Grenier, F. Labrique, S. Gusia, Dynamic modelling of power electronic converters using a describing function like approach, in: Proceedings of the ELECTRIMACS’99 Conference, vol. 1, Lisbon, Portugal, 1999, pp. 7–14]. But they are unable to predict the ripples induced by the switching behavior of the power semiconductor switches.The aim of this paper is to show for power electronic systems using a power electronic converter working in a PWM mode, how it is possible to define a global dynamical model including a dynamical model of the ripple effects. [Copyright &y& Elsevier]