Results 21 to 30 of about 1,903,470 (246)
Almost periodic sequences and functions with given values [PDF]
, 2011 summary:We present a method for constructing almost periodic sequences and functions with values in a metric space. Applying this method, we find almost periodic sequences and functions with prescribed values.
Veselý, Michal
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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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Advances in Difference Equations, 2011 We establish a composition theorem of Stepanov almost periodic functions, and, with its help, a composition theorem of Stepanov-like pseudo almost periodic functions is obtained.
Hui-Sheng Ding, Wei Long
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Asymptotically almost periodic solutions of limit and almost periodic linear difference systems
Electronic Journal of Qualitative Theory of Differential Equations, 2015 In this paper, limit periodic and almost periodic homogeneous linear difference systems are considered. We study the systems in which the coefficient matrices are taken from a given bounded group and the elements of the matrices are from an infinite ...
Martin Chvátal
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Quasicrystals and Almost Periodicity [PDF]
Communications in Mathematical Physics, 2005 We introduce a topology ${\cal T}$ on the space $U$ of uniformly discrete subsets of the Euclidean space. Assume that $S$ in $U$ admits a unique autocorrelation measure. The diffraction measure of $S$ is purely atomic if and only if $S$ is almost periodic in $(U,{\cal T})$. This result relates idealized quasicrystals to almost periodicity.
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Almost periodicity in semiflows [PDF]
Proceedings of the American Mathematical Society, 1995 For a semiflow on a complete metric space we show that if a semiorbit has compact closure and its positive limit set consists of stable points, the orbit is asymptotically almost periodic. Under stronger hypotheses which are more tractable in applications, the same conclusion holds. An application to a scalar delay-differential equation is given.
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Almost periodic solutions with a prescribed spectrum of linear and quasilinear differential equations with almost periodic coefficients and constant time lag (Neutral differential equations) [PDF]
, 2012 summary:The paper is the extension of the author's previous papers and solves more complicated problems. Almost periodic solutions of a certain type of almost periodic linear or quasilinear systems of neutral differential equations are dealt ...
Fischer, Alexandr
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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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Cocycles and Almost Periodicity [PDF]
Journal of the London Mathematical Society, 1987 Let G be a compact abelian group containing, as a dense subgroup, the image of \({\mathbb{R}}\) by a continuous injective homomorphism, say \(\alpha\). A cocycle on G is defined here as a unitary \((=\) of modulus 1) continuous function on \(G\times {\mathbb{R}}\) satisfying the identity \(Y(g,s+t)=Y(g,s)Y(g+\alpha (s),t)\). A cocycle is called trivial
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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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