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Related papers: A Note on Spherical Needlets

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We present here a simple construction of a wavelet system for the three-dimensional ball, which we label \emph{Radial 3D Needlets}. The construction envisages a data collection environment where an observer located at the centre of the ball…

Instrumentation and Methods for Astrophysics · Physics 2014-12-03 Claudio Durastanti , Yabebal T. Fantaye , Frode K. Hansen , Domenico Marinucci , Isaac Z. Pesenson

Curvelets are efficient to represent highly anisotropic signal content, such as a local linear and curvilinear structure. First-generation curvelets on the sphere, however, suffered from blocking artefacts. We present a new…

Information Theory · Computer Science 2016-11-29 Jennifer Y. H. Chan , Boris Leistedt , Thomas D. Kitching , Jason D. McEwen

Accurate lighting estimation is challenging yet critical to many computer vision and computer graphics tasks such as high-dynamic-range (HDR) relighting. Existing approaches model lighting in either frequency domain or spatial domain which…

Computer Vision and Pattern Recognition · Computer Science 2021-06-25 Fangneng Zhan , Changgong Zhang , Wenbo Hu , Shijian Lu , Feiying Ma , Xuansong Xie , Ling Shao

We show that dielectric spheres can be cloaked by a shell of amorphously arranged metallic nanoparticles. The shell represents an artificial medium with tunable effective properties that can be adjusted such that the scattered signals of…

Other Condensed Matter · Physics 2012-06-15 Stefan Muhlig , Mohamed Farhat , Carsten Rockstuhl , Falk Lederer

It is proved that harmonic functions are characterized by harmonicity of their spherical means, for which purpose the iterated spherical means are used. The similar characterization of solutions to the modified Helmholtz equation…

Analysis of PDEs · Mathematics 2021-10-12 Nikolay Kuznetsov

We survey many of the important properties of spherically symmetric spacetimes as follows. We present several different ways of describing a spherically symmetric spacetime and the resulting metrics. We then focus our discussion on an…

General Relativity and Quantum Cosmology · Physics 2014-10-10 Alan R. Parry

In recent years, there has been a mounting interest in better methods of measuring nanoscale objects, especially in fields such as nanotechnology, biomedicine, cleantech, and microelectronics. Conventional methods have proved insufficient,…

Optics · Physics 2015-06-16 Evyatar Hemo , Boris Spektor , Joseph Shamir

This paper provides quantitative Central Limit Theorems for nonlinear transforms of spherical random fields, in the high frequency limit. The sequences of fields that we consider are represented as smoothed averages of spherical Gaussian…

Probability · Mathematics 2018-01-09 Valentina Cammarota , Domenico Marinucci

This work presents the construction of a novel spherical wavelet basis designed for incomplete spherical datasets, i.e. datasets which are missing in a particular region of the sphere. The eigenfunctions of the Slepian spatial-spectral…

Information Theory · Computer Science 2023-04-24 Patrick J. Roddy , Jason D. McEwen

Shearlet theory has become a central tool in analyzing and representing 2D data with anisotropic features. Shearlet systems are systems of functions generated by one single generator with parabolic scaling, shearing, and translation…

Functional Analysis · Mathematics 2010-11-23 Gitta Kutyniok , Jakob Lemvig , Wang-Q Lim

Space-time light structuring has emerged as a very powerful tool for controlling the propagation dynamics of pulsed beam. The ability to manipulate and generate space-time distributions of light has been remarkably enhanced in past few…

Optics · Physics 2022-10-26 Pierre Béjot , Bertrand Kibler

Wavelets are closely related to the Schr\"odinger's wave functions and the interpretation of Born. Similarly to the appearance of atomic orbital, it is proposed to combine anti-symmetric wavelets into orbital wavelets. The proposed approach…

Signal Processing · Electrical Eng. & Systems 2020-10-02 H. M. de Oliveira , V. V. Vermehren , R. J. Cintra

This review paper is intended to give a useful guide for those who want to apply discrete wavelets in their practice. The notion of wavelets and their use in practical computing and various applications are briefly described, but rigorous…

High Energy Physics - Phenomenology · Physics 2025-10-20 I. M. Dremin , O. V. Ivanov , V. A. Nechitailo

In this article, we present a space-frequency theory for spherical harmonics based on the spectral decomposition of a particular space-frequency operator. The presented theory is closely linked to the theory of ultraspherical polynomials on…

Numerical Analysis · Mathematics 2013-07-16 Wolfgang Erb , Sonja Mathias

Circular-harmonic spectra are a compact representation of local image features in two dimensions. It is well known that the computational complexity of such transforms is greatly reduced when polar separability is exploited in steerable…

Computer Vision and Pattern Recognition · Computer Science 2020-11-09 Hugh L Kennedy

Tensor harmonics are a useful mathematical tool for finding solutions to differential equations which transform under a particular representation of the rotation group $\mathrm{SO}(3)$. The aim of this work is to make use of this tool also…

Mathematical Physics · Physics 2020-01-24 Manuel Hohmann

Manufacturing of particulate products across many industries relies on accurate measurements of particle size distributions in dispersions or powders. Laser diffraction (or small angle light scattering) is commonly used, usually off-line,…

Soft Condensed Matter · Physics 2016-10-18 Okpeafoh S. Agimelen , Anthony J. Mulholland , Jan Sefcik

We consider the correlation structure of the random coefficients for a wide class of wavelet systems on the sphere (Mexican needlets) which were recently introduced in the literature by Geller and Mayeli (2007). We provide necessary and…

Statistics Theory · Mathematics 2010-04-30 Xiaohong Lan , Domenico Marinucci

The paper presents a versatile library of analytic and quasi-analytic complex-valued wavelet packets (WPs) which originate from discrete splines of arbitrary orders. The real parts of the quasi-analytic WPs are the regular spline-based…

Numerical Analysis · Mathematics 2019-07-04 Amir Averbuch , Pekka Neittaanmaki , Valery Zheludev

Flexible bandwidth needlets offer a versatile multiscale framework for analyzing functions on the sphere. A key element in their construction is the dilation sequence, which controls how the multipole consecutive scales are spaced and…

Statistics Theory · Mathematics 2025-07-11 Claudio Durastanti