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Extra Invariance of a Shift-Invariant Space in LCA Groups
(Elsevier, 2010-10)
This article generalizes recent results in the extra invariance for shift-invariant spaces to the context of LCA groups. Let G be a locally compact abelian (LCA) group and K a closed subgroup of G. A closed subspace of ...
Invariance of a Shift-Invariant Space in Several Variables
(Springer, 2011-12)
In this article we study invariance properties of shift-invariant spaces in higher dimensions. We state and prove several necessary and sufficient conditions for a shift-invariant space to be invariant under a given closed ...
Invariance of a shift-invariant space
(Birkhauser Boston Inc, 2010-01)
A shift-invariant space is a space of functions that is invariant under integer translations. Such spaces are often used as models for spaces of signals and images in mathematical and engineering applications. This paper ...
An approximation problem in multiplicatively invariant spaces
(American Mathematical Society, 2017-07)
Let H be Hilbert space and (Ω, m) a σ-finite measure space. Multiplicatively invariant(MI) spaces are closed subspaces of L2(Ω, H) that are invariant under point-wise multiplication byfunctions from a fixed subset of L∞(Ω). ...
Subspaces with extra invariance nearest to observed data
(Elsevier Inc, 2016-09)
Given an arbitrary finite set of data F = {f1, ..., fm} ⊂ L2(Rd) we prove the existence and show how to construct a “small shift invariant space” that is “closest” to the data F over certain class of closed subspaces of ...
Linear combinations of frame generators in systems of translates
(Elsevier Inc, 2013-12)
A finitely generated shift invariant space V is a closed subspace of L2(Rd) that can be generated by the integer translates of a finite number of functions. A set of frame generators for V is a set of functions whose integer ...
Boundedness of convolution operators with smooth kernels on Orlicz spaces
(Polish Academy of Sciences. Institute of Mathematics, 2002-12)
We study boundedness in Orlicz norms of convolution operators with integrable kernels satisfying a generalized Lipschitz condition with respect to normal quasidistances of ℝn and continuity moduli given by growth functions.
Shift-modulation invariant spaces on LCA groups
(Polish Academy of Sciences. Institute of Mathematics, 2012)
A (K,Λ) shift-modulation invariant space is a subspace of L2(G) that is invariant under translations along elements in K and modulations by elements in Λ. Here G is a locally compact abelian group, and K and Λ are closed ...
Frames of translates with prescribed fine structure in shift invariant spaces
(Academic Press Inc Elsevier Science, 2016-11)
For a given finitely generated shift invariant (FSI) subspace W⊂L2(Rk) we obtain a simple criterion for the existence of shift generated (SG) Bessel sequences E(F) induced by finite sequences of vectors F∈Wn that have a ...