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Related papers: Inversion of the Weighted Spherical Mean

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This manuscript introduces a generalization of the Mellin integral transform within the framework of weighted fractional calculus with respect to an increasing function. The proposed transform is much more suitable for working with…

Functional Analysis · Mathematics 2025-12-09 Gustavo Dorrego , Luciano Luque y Rubén Cerutti

Let $\mR$ be the restriction of the spherical Radon transform to the set of spheres centered on a hypersurface $\mS$. We study the inversion of $\mR$ by a closed-form formula. We approach the problem by studying an oscillatory integral,…

Classical Analysis and ODEs · Mathematics 2013-07-11 Linh V. Nguyen

The spherical means Radon transform $\mathcal{M}f(x,r)$ is defined by the integral of a function $f$ in $\mathbb{R}^{n}$ over the sphere $S(x,r)$ of radius $r$ centered at a $x$, normalized by the area of the sphere. The problem of…

Analysis of PDEs · Mathematics 2023-02-08 Mark Agranovsky , Leonid Kunyansky

Regularization methods are a key tool in the solution of inverse problems. They are used to introduce prior knowledge and make the approximation of ill-posed (pseudo-)inverses feasible. In the last two decades interest has shifted from…

Numerical Analysis · Mathematics 2018-01-31 Martin Benning , Martin Burger

The concept of turnaround surface in an accelerating universe is generalized to arbitrarily large deviations from spherical symmetry, to close the gap between the idealized theoretical literature and the real world observed by astronomers.…

General Relativity and Quantum Cosmology · Physics 2021-03-03 Andrea Giusti , Valerio Faraoni

We present an approach to sums of random Hermitian matrices via the theory of spherical functions for the Gelfand pair $(\mathrm{U}(n) \ltimes \mathrm{Herm}(n), \mathrm{U}(n))$. It is inspired by a similar approach of Kieburg and K\"osters…

Probability · Mathematics 2022-10-05 Arno B. J. Kuijlaars , Pablo Román

The notion of the weighted core inverse in a ring with involution was introduced, recently [Mosic et al. Comm. Algebra, 2018; 46(6); 2332-2345]. In this paper, we explore new representation and characterization of the weighted core inverse…

Rings and Algebras · Mathematics 2020-05-05 Sourav Das , Jajati Keshari Sahoo , Ratikanta Behera

Introducing a notion of the weighted mean sigma-r curvature and using the weighted Newton transformations we derive in this paper some integral formulae on weighted manifolds. These formulae generalize the flux formula and some of its…

Differential Geometry · Mathematics 2020-07-30 Mohammed Abdelmalek , Mohammed Benalili

Higher spatial resolution and larger imaging scene are always the goals pursued by advanced space-borne SAR system.High resolution and wide swath SAR imaging can provide more information about the illuminated scene of interest on one…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Xinhua Mao

In this paper, studying the inverse problem, we establish a curvature compatibility condition on a spherically symmetric Finsler metric. As an application, we characterize the spherically symmetric metrics of scalar curvature. We construct…

Differential Geometry · Mathematics 2024-07-08 S. G. Elgendi

We introduce a generalization of the Stirling numbers via symmetric functions involving two weight functions. The resulting extension unifies previously known Stirling-type sequences with known symmetric function forms, as well as other…

In this paper, we study the inversion formula for recovering a function from its windowed Fourier transform. We give a rigorous proof for an inversion formula which is known in engineering. We show that the integral involved in the formula…

Functional Analysis · Mathematics 2011-09-21 Wenchang Sun

We consider integrals of spherical harmonics with Fourier exponents on the sphere $S^n ,\, n \geq 1$. Such transforms arise in the framework of the theory of weighted Radon transforms and vector diffraction in electromagnetic fields theory.…

Classical Analysis and ODEs · Mathematics 2017-07-11 F Goncharov

Considering the weighted concept of majorization, Sherman obtained generalization of majorization inequality for convex functions known as Sherman's inequality. We extend Sherman's result to the class of n-strongly convex functions using…

Classical Analysis and ODEs · Mathematics 2019-05-21 Slavica Ivelić Bradanović

An ill-defined integral equation for modeling the mass-spectrum of mesons is regulated with an additional but unphysical parameter. This parameter dependance is removed by renormalization. Illustrative graphical examples are given.

High Energy Physics - Phenomenology · Physics 2009-11-07 Michael Frewer , Tobias Frederico , Hans-Christian Pauli

The weighted Selberg integral is a discrete mean-square, that is a generalization of the classical Selberg integral of primes to an arithmetic function $f$, whose values in a short interval are suitably attached to a weight function. We…

Number Theory · Mathematics 2019-01-15 Giovanni Coppola , Maurizio Laporta

The inequality of Berwald is a reverse-H\"older like inequality for the $p$th average, $p\in (-1,\infty),$ of a non-negative, concave function over a convex body in $\mathbb{R}^n.$ We prove Berwald's inequality for averages of functions…

Metric Geometry · Mathematics 2025-06-04 Dylan Langharst , Eli Putterman

We consider the inverse problem of the broken ray transform (sometimes also referred to as the V-line transform). Explicit image reconstruction formulas are derived and tested numerically. The obtained formulas are generalizations of the…

Mathematical Physics · Physics 2011-01-07 Lucia Florescu , Vadim A. Markel , John C. Schotland

We introduce a technique for recovering a sufficiently smooth function from its ray transform over a wide class of curves in a general region of Euclidean space. The method is based on a complexification of the underlying vector fields…

Complex Variables · Mathematics 2010-11-17 Nicholas Hoell , Guillaume Bal

Finding a computationally efficient algorithm for the inverse continuous wavelet transform is a fundamental topic in applications. In this paper, we show the convergence of the inverse wavelet transform.

Functional Analysis · Mathematics 2010-09-01 Wenchang Sun