Results 31 to 40 of about 7,009,663 (303)

Almost periodic solutions with a prescribed spectrum of systems of linear and quasilinear differential equations with almost periodic coefficients and constant time lag (Fourier transform approach) [PDF]

, 2004
summary:This paper is a continuation of my previous paper in Mathematica Bohemica and solves the same problem but by means of another method. It deals with almost periodic solutions of a certain type of almost periodic systems of differential ...
Fischer, Alexandr
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Approximation of almost periodic functions by periodic ones [PDF]

, 1998
summary:It is not the purpose of this paper to construct approximations but to establish a class of almost periodic functions which can be approximated, with an arbitrarily prescribed accuracy, by continuous periodic functions uniformly on ${\mathbb R} =
Fischer, Alexander
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Stability of unique pseudo almost periodic solutions with measure [PDF]

, 2020
summary:By means of the fixed-point methods and the properties of the $\mu $-pseudo almost periodic functions, we prove the existence, uniqueness, and exponential stability of the $\mu $-pseudo almost periodic solutions for some models of recurrent ...
Ghanmi, Boulbaba, Miraoui, Mohsen
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Partially irregular almost periodic solutions of ordinary differential systems [PDF]

, 2001
summary:Let $f(t,x)$ be a vector valued function almost periodic in $t$ uniformly for $x$, and let ${\mathrm mod}(f)=L_1\oplus L_2$ be its frequency module.
Demenchuk, Alexandr
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On the existence of almost periodic solutions of neutral functional differential equations

Electronic Journal of Qualitative Theory of Differential Equations, 1998
This paper discusses the existence of almost periodic solutions of neutral functional differential equations. Using a Liapunov function and the Razumikhin's technique, we obtain the existence, uniqueness and stability of almost periodic solutions.
J. Xu, Zicheng Wang, Z. Zheng
doaj   +1 more source

On the Relation Between Fourier Frequency and Period for Discrete Signals, and Series of Discrete Periodic Complex Exponentials

IEEE Open Journal of Signal Processing, 2021
Discrete complex exponentials are almost periodic signals, not always periodic; when periodic, the frequency determines the period, but not viceversa, the period being a chaotic function of the frequency, expressible in terms of Thomae's function.
Alfredo Restrepo, Julian Quiroga, Jairo Hurtado   +2 more
doaj   +1 more source

Almost Periodic and Asymptotically Almost Periodic Solutions of Liénard Equations [PDF]

, 2011
The aim of this paper is to study the almost periodic and asymptotically almost periodic solutions on (0,+1) of the Li´enard equation x′′ + f(x)x′ + g(x) = F(t), where F : T !
null null, David Cheban, Caraballo Garrido, Tomás, Cheban, David, Tomás Caraballo   +4 more
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Almost-Periodic Weak Solutions of Second-Order Neutral Delay-Differential Equations with Piecewise Constant Argument

Advances in Difference Equations, 2008
We investigate the existence of almost-periodic weak solutions of second-order neutral delay-differential equations with piecewise constant argument of the form (x(t)+x(t−1))′′=qx(2[(t+1)/2])+f(t), where [⋅] denotes the greatest ...
Chuanyi Zhang, Li Wang
doaj   +2 more sources

A Periodic Systems Toolbox for MATLAB [PDF]

, 2005
The recently developed Periodic Systems Toolbox for MATLAB is described. The basic approach to develop this toolbox was to exploit the powerful object manipulation features of MATLAB via flexible andfunctionally rich high level m-functions, while ...
A. Varga, Varga, A.
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The Set of Idempotents in the Weakly Almost Periodic Compactification of the Integers is not Closed [PDF]

, 2000
This paper answers negatively the question of whether the sets of idempotents in the weakly almost periodic compacti?cations of (N; +) and (Z; +) are ...
Pym, J.S., Bordbar, Behzad
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