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71.
Lahcen MokniMohamed Belhaq 《Communications in Nonlinear Science & Numerical Simulation》2012,17(4):1980-1985
In Mokni et al. [Mokni L, Belhaq M, Lakrad F. Effect of fast parametric viscous damping excitation on vibration isolation in sdof systems. Commun Nonlinear Sci Numer Simulat 2011;16:1720-1724], it was shown that in a single degree of freedom system a fast nonlinear parametric damping enhances vibration isolation with respect to the case where the nonlinear damping is time-independent. The present work proposes additional enhancement of vibration isolation using delayed nonlinear damping. Attention is focused on assessing the contribution of a delayed nonlinear damping over a fast parametric damping in terms of minimizing transmissibility. The results show that a nonlinear damping with delay greatly improves vibration isolation. 相似文献
72.
We define a functional analytic transform involving the Chebyshev polynomials Tn(x), with an inversion formula in which the Möbius function μ(n) appears. If s∈C with Re(s)>1, then given a bounded function from [−1,1] into C, or from C into itself, the following inversion formula holds:
73.
74.
I. B. Simonenko 《Mathematical Notes》2005,78(1-2):239-250
We study the asymptotic behavior of the averaged f-trace of a truncated generalized multidimensional discrete convolution operator as the truncation domain expands. By definition, the averaged f-trace of a finite-dimensional operator A is equal to
, where n is the dimension of the space in which the operator A acts, the set of numbers γk, k = 1,..., n, is the complete collection of eigenvalues of the operator A, counting multiplicity; a generalized discrete convolution is an operator from the closure of the algebra generated by discrete convolution operators and by operators of multiplication by functions admitting a continuous continuation onto the sphere at infinity.__________Translated from Matematicheskie Zametki, vol. 78, no. 2, 2005, pp. 265–277.Original Russian Text Copyright © 2005 by I. B. Simonenko. 相似文献
75.
In a recent paper [P. Bates, A. Chmaj, A discrete convolution model for phase transition, Arch. Rational Mech. Anal. 150 (1999) 281-305], a discrete convolution model for Ising-like phase transition has been derived, and the existence, uniqueness of traveling waves and stability of stationary solution have been studied. This nonlocal model describes l2-gradient flow for a Helmholts free energy functional with general range interaction. In this paper, by using the comparison principle and the squeezing technique, we prove that the traveling wavefronts with nonzero speed is globally asymptotic stable with phase shift. 相似文献
76.
IntroductionItiswell_knownthattheLaplacetransformoftheproductoftwotime_domainsignalsequalsthecomplexfrequency_domainconvolutionofindividualLaplacetransformsoftwosignals.Generally,theconvolutionoftwocomplexfrequency_domainanalyticalfunctionsiscalculate… 相似文献
77.
In this paper we give a first attempt to define and study stable distributions with respect to the weak generalized convolution,
focusing our attention on the symmetric weakly stable distribution. As in the case of the classical convolution, characterization
of distributions stable in the sense of weak generalized convolution depends on solving some functional equations in the class
of characteristic functions.
This paper was partially written while the second author was a visiting professor of Delft Institute of Applied Mathematics,
Delft University of Technology, Holland. 相似文献
78.
罗英语 《数学的实践与认识》2016,(21):223-230
讨论了具x/ζ型卷积核的奇异积分方程的求解问题.通过Fourier积分变换,将所讨论的积分方程转化成在一定可解条件下与其同解意义下等价的Riemann边值问题.利用Riemann边值问题理论,分别讨论了在正则和非正则两种情况下的Riemann边值问题,进而得到相对应的x/ζ变量比型卷积核的积分方程一般解及可解条件. 相似文献
79.
The time discretization in classes of integro‐differential equations with completely monotonic kernels: Weighted asymptotic convergence 下载免费PDF全文
Da Xu 《Numerical Methods for Partial Differential Equations》2016,32(3):896-935
We consider the time discretization for the solution of the equation with . Here, the operators Lj are densely defined positive self‐adjoint linear operator on a Hilbert space H and have spectral decompositions with respect to a common resolution of the identity in H . The kernel functions , are assumed to be completely monotonic on (0,∞) and locally integrable, but not constant. The considered time discretization method comes from [Da Xu, Science China Mathematics 56 (2013), 395–424], where the backward Euler method is combined with order one convolution quadrature for approximating the integral term. In this article, the convergence properties of the time discretization are given in the weighted and norm, where ρ is a given weighted function. Numerical experiments show the theoretical results. © 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 896–935, 2016 相似文献
80.