Displaying similar documents to “Existence of almost-periodic ultra-weak solutions to the equation u ' ( t ) = a ( t ) A u ( t ) + f ( t ) in Hilbert spaces”

Almost periodic solutions with a prescribed spectrum of systems of linear and quasilinear differential equations with almost periodic coefficients and constant time lag (Cauchy integral)

Alexandr Fischer (1999)

Mathematica Bohemica

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This paper generalizes earlier author's results where the linear and quasilinear equations with constant coefficients were treated. Here the method of limit passages and a fixed-point theorem is used for the linear and quasilinear equations with almost periodic coefficients.

Approximation of almost periodic functions by periodic ones

Alexander Fischer (1998)

Czechoslovak Mathematical Journal

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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 ℝ = ( - ∞ ; + ∞ ) .