New Trends in Applied Harmonic Analysis, Volume 2
Harmonic Analysis, Geometric Measure Theory, and Applications
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A correction to this paper has been published: https://doi.org/10.1007/s43670-021-00010-6
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We characterize the normal operators A on \(\ell ^2\) ℓ 2 ...
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In this paper, we consider systems of vectors in a Hilbert space ℋ \(\mathcal {H}\) ...
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We consider bounded operators A acting iteratively on a finite set of vectors {fi: i ∈ I} in a Hilbert space ℌ and address the problem of providing necessary and sufficient conditions for the collection of iterat...
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This paper aims to identify those regions within the South American continent where the Regional Climate Models (RCMs) have the potential to add value (PAV) compared to their coarser-resolution global forcing....
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In this paper we prove the existence of a time-frequency space that best approximates a given finite set of data. Here best approximation is in the least square sense, among all time-frequency spaces with no m...
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Harmonic Analysis, Geometric Measure Theory, and Applications
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Sparse Representations, Compressed Sensing, and Multifractal Analysis
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In this chapter we study for which Cantor sets there exists a gauge-function h, such that the h−Hausdorff measure—is positive and finite. We show that the collection of sets for which this is true is dense in the...
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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...
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Given a set of points F in a high dimensional space, the problem of finding a union of subspaces ∪i Vi ⊆ RN that best explains the data F increases dramatically with the dimension of RN. In this article, we study...
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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....
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A new paradigm in sampling theory has been developed recently by Lu and Do. In this new approach the classical linear model is replaced by a non-linear, but structured, model consisting of a union of subspaces...
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Given a set of vectors (the data) in a Hilbert space ℋ, we prove the existence of an optimal collection of subspaces minimizing the sum of the square of the distances between each vector and its closest subspa...
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Given a function ψ in \({\cal L}^2({\Bbb R}^d),\) the affine (wavelet) system generated by ψ, associated to an inverti...
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Sampling theory in spaces other than the space of band-limited functions has recently received considerable attention. This is in part because the band-limitedness assumption is not very realistic in many appl...
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In this chapter we discuss the problem of finding the shift-invariant space model that best fits a given class of observed data F. If the data is known to belong to a fixed—but unknown—shift-invariant space V(Φ) ...
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Compactly supported distributions f1,..., fr on ℝd are fefinable if each fi is a finite linear combination of the rescaled and translated distributions fj(Ax−k), where the translates k are taken along a lattice Γ...