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We prove end point estimate for Radon transform of radial functions on affine Grasamannian and real hyperbolic space. We also discuss analogs of these results on the sphere.

Functional Analysis · Mathematics 2012-05-08 Ashisha Kumar , Swagato K. Ray

We develop a sampling scheme on the sphere that permits accurate computation of the spherical harmonic transform and its inverse for signals band-limited at $L$ using only $L^2$ samples. We obtain the optimal number of samples given by the…

Information Theory · Computer Science 2014-07-25 Zubair Khalid , Rodney A. Kennedy , Jason D. McEwen

This work characterizes the range of the single-quadrant approximate discrete Radon transform (ADRT) of square images. The characterization follows from a set of linear constraints on the codomain. We show that for data satisfying these…

Numerical Analysis · Mathematics 2022-03-23 Weilin Li , Kui Ren , Donsub Rim

Radon transform is a type of transform which is used in image processing to transfer the image into intercept-slope coordinate. Its diagonal properties made it appropriate for some applications which need processes in different degrees.…

Computer Vision and Pattern Recognition · Computer Science 2017-01-19 M. A. Khorsandi , N. Karimi , S. Samavi

We consider discrete analogues of fractional Radon transforms involving integration over paraboloids defined by positive definite quadratic forms. We prove that such discrete operators extend to bounded operators from $\ell^p$ to $\ell^q$…

Classical Analysis and ODEs · Mathematics 2019-12-19 Lillian B. Pierce

In this paper, we investigate in detail the structures of the variational characterization $A_{N,t}$ of the spherical $t$-design, its gradient $\nabla A_{N,t}$, and its Hessian $\mathcal{H}(A_{N,t})$ in terms of fast spherical harmonic…

Numerical Analysis · Mathematics 2023-12-06 Yuchen Xiao , Xiaosheng Zhuang

In this paper we establish a multiscale approximation for random fields on the sphere using spherical needlets --- a class of spherical wavelets. We prove that the semidiscrete needlet decomposition converges in mean and pointwise senses…

Numerical Analysis · Mathematics 2016-12-13 Quoc T. Le Gia , Ian H. Sloan , Yu Guang Wang , Robert S. Womerlsey

We define spherical diffraction measures for a wide class of weighted point sets in commutative spaces, i.e. proper homogeneous spaces associated with Gelfand pairs. In the case of the hyperbolic plane we can interpret the spherical…

Dynamical Systems · Mathematics 2020-02-14 Michael Björklund , Tobias Hartnick , Felix Pogorzelski

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

In the last decade diffusion MRI has become a powerful tool to non-invasively study white-matter integrity in the brain. Recently many research groups have focused their attention on multi-shell spherical acquisitions with the aim of…

Quantitative Methods · Quantitative Biology 2011-06-02 A. Daducci , J. D. McEwen , D. Van De Ville , J. -Ph. Thiran , Y. Wiaux

I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 T. D. Carozzi

Needlets have been recognized as state-of-the-art tools to tackle spherical data, due to their excellent localization properties in both spacial and frequency domains. This paper considers developing kernel methods associated with the…

Machine Learning · Computer Science 2015-09-11 Shaobo Lin

Tomographic investigations are a central tool in medical applications, allowing doctors to image the interior of patients. The corresponding measurement process is commonly modeled by the Radon transform. In practice, the solution of the…

Numerical Analysis · Mathematics 2025-10-17 Richard Huber

We propose and study a new quasi-interpolation method on spheres featuring the following two-phase construction and analysis. In Phase I, we analyze and characterize a large family of zonal kernels (e.g., the spherical version of Poisson…

Numerical Analysis · Mathematics 2025-08-27 Zhengjie Sun , Wenwu Gao , Xingping Sun

We study properties of the general integral transform defined for a family of hypersurfaces in a smooth manifold. Estimates of Sobolev norms, range conditions and approximation theorem for the kernel of the integral transform are stated.…

Analysis of PDEs · Mathematics 2007-05-23 Victor Palamodov

We study the light scattering of homogenous radially-anisotropic spherical particles. It is shown that radial anisotropy can be employed to tune effectively the electric resonances, and thus enable flexible overlapping of electric and…

Optics · Physics 2023-07-19 Wei Liu

In this manuscript, we obtain a plane wave decomposition for the delta distribution in superspace, provided that the superdimension is not odd and negative. This decomposition allows for explicit inversion formulas for the super Radon…

Mathematical Physics · Physics 2021-07-13 Alí Guzmán Adán , Irene Sabadini , Frank Sommen

We study the Radon transform in the plane in parallel geometry possibly undersampled in the angular variables. We study resolution, aliasing artifacts, and edge recovery.

Analysis of PDEs · Mathematics 2022-08-12 Plamen Stefanov

We provide explicit, simple, geometric formulas for free involutions rho of Euclidean spheres that are not conjugate to the antipodal involution. Therefore the quotient S^n/rho is a manifold that is homotopically equivalent but not…

Geometric Topology · Mathematics 2007-05-23 Uwe Abresch , Carlos Duran , Thomas Puettmann , A. Rigas

We study the inversion of the conical Radon which integrates a function in three-dimensional space from integrals over circular cones. The conical Radon recently got significant attention due to its relevance in various imaging applications…

Numerical Analysis · Mathematics 2020-02-26 Markus Haltmeier , Sunghwan Moon