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Related papers: Oversampling of wavelet frames for real dilations

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In this paper we present two different problems within the framework of shift-invariant theory. First, we develop a triangular form for shift-preserving operators acting on finitely generated shift-invariant spaces. In case of the normal…

Functional Analysis · Mathematics 2026-01-12 Elona Agora , Jorge Antezana , Diana Carbajal

We consider the application of the polyharmonic subdivision wavelets (of Daubechies type) to Image Processing, in particular to Astronomical Images. The results show an essential advantage over some standard multivariate wavelets and a…

Numerical Analysis · Mathematics 2010-07-01 Ognyan Kounchev , Damyan Kalaglarsky , Milcho Tsvetkov

In this article, we develop a general method for constructing wavelets {|det A_j|^{1/2} g(A_jx-x_{j,k}): j in J, k in K}, on irregular lattices of the form X={x_{j,k} in R^d: j in J, k in K}, and with an arbitrary countable family of…

Classical Analysis and ODEs · Mathematics 2007-05-23 Akram Aldroubi , Carlos Cabrelli , Ursula M. Molter

Due to the emergence of new high resolution numerical weather prediction (NWP) models and the availability of new or more reliable remote sensing data, the importance of efficient spatial verification techniques is growing. Wavelet…

Atmospheric and Oceanic Physics · Physics 2017-04-05 Michael Weniger , Florian Kapp , Petra Friederichs

We study quadrupole and monopole core polarization using harmonic oscillator wave funtions but with different length parameters for the valence particle as compared to the core. We use perturbation theory with a delta interaction. The…

Nuclear Theory · Physics 2011-04-01 Larry Zamick

The paper shows that under some mild conditions $n$-dimensional spherical wavelets derived from approximate identities build semi-continuous frames. Moreover, for sufficiently dense grids Poisson wavelets on $n$-dimensional spheres…

Classical Analysis and ODEs · Mathematics 2018-03-09 Ilona Iglewska-Nowak

A set of on shell duality equations is proposed that leads to a map between strings moving on symmetric spaces with opposite curvatures. The transformation maps "waves" on a riemannian symmetric space to "waves" on its dual riemannian…

High Energy Physics - Theory · Physics 2009-10-31 Orlando Alvarez

Extensions of standard one-dimensional supersymmetric quantum mechanics are discussed. Supercharges involving higher order derivatives are introduced leading to an algebra which incorporates a higher order polynomial in the Hamiltonian. We…

High Energy Physics - Theory · Physics 2010-04-06 A. A. Andrianov , F. Cannata , J. -P-Dedonder , M. V. Ioffe

Factorization of matrices of Laurent polynomials plays an important role in mathematics and engineering such as wavelet frame construction and filter bank design. Wavelet frames (a.k.a. framelets) are useful in applications such as signal…

Classical Analysis and ODEs · Mathematics 2021-12-03 Chenzhe Diao , Bin Han , Ran Lu

We examine additional symmetries of specific refraction index profiles that are used in the well-known phenomena of perfect imaging and cloaking.In the considered cases, the translation generator and the angular momentum are conserved. We…

Optics · Physics 2020-03-26 Zhyrair Gevorkian , Mher Davtyan , Armen Nersessian

We analyze the backreaction of dilaton tadpoles on the geometry of non-supersymmetric strings. After finding explicit warped solutions for a T-dual version of the Sugimoto model, we examine the possibility of realizing large extra dimension…

High Energy Physics - Theory · Physics 2009-10-31 Ralph Blumenhagen , Anamaria Font

Excitation of waves in a three-layer acoustic wavegide is studied. The wave field is presented as a sum of integrals. The summation is held over all waveguide modes. The integration is performed over the temporal frequency axis. The…

Analysis of PDEs · Mathematics 2017-04-04 A. V. Shanin , K. S. Knyazeva

We show that the Calder\'on sum formula for orthonormal wavelet bases holds for arbitrary dilation and translation matrices under a mild condition on the wavelet function. This partially solves a conjecture by Bownik and Lemvig.

Classical Analysis and ODEs · Mathematics 2026-02-12 Ulrik Enstad , Jordy Timo van Velthoven

Two transformation-optics inspired flat lenses are used to build up an optical system capable to transpose an area surrounding the object focal point in a magnified area surrounding the image focal point. The object and image focal points…

Optics · Physics 2018-08-10 Mircea Giloan , Robert Gutt

Intrinsic wavelet transforms and wavelet estimation methods are introduced for curves in the non-Euclidean space of Hermitian positive definite matrices, with in mind the application to Fourier spectral estimation of multivariate stationary…

Methodology · Statistics 2019-11-12 Joris Chau , Rainer von Sachs

We suggest a two-dimensional wavelet devised to deduce the large-scale structure of a physical field (e.g., the Galactic magnetic field) from its integrals along straight paths from irregularly spaced data points to a fixed interior point…

Astrophysics · Physics 2009-11-07 R. Stepanov , P. Frick , A. Shukurov , D. Sokoloff

We present a general theory of fractal transformations and show how it leads to a new type of method for filtering and transforming digital images. This work substantially generalizes earlier work on fractal tops. The approach involves…

Geometric Topology · Mathematics 2011-02-17 Michael F. Barnsley , Brendan Harding , Konstantin Igudesman

The development of wavelet theory has in recent years spawned applications in signal processing, in fast algorithms for integral transforms, and in image and function representation methods. This last application has stimulated interest in…

Methodology · Statistics 2009-09-29 Anestis Antoniadis

The most general form of a marginal extended perturbation in a two-dimensional system is deduced from scaling considerations. It includes as particular cases extended perturbations decaying either from a surface, a line or a point for which…

High Energy Physics - Theory · Physics 2009-10-22 L. Turban , B. Berche

This work studies the problem of estimating a two-dimensional superposition of point sources or spikes from samples of their convolution with a Gaussian kernel. Our results show that minimizing a continuous counterpart of the $\ell_1$ norm…

Numerical Analysis · Mathematics 2020-08-05 Joseph McDonald , Brett Bernstein , Carlos Fernandez-Granda