English
Related papers

Related papers: Fourier-based Inversion of Partial X-ray Transform…

200 papers

X-ray interaction with matter is an energy-dependent process that is contingent on the atomic structure of the constituent material elements. The most advanced models to capture this relationship currently rely on Monte Carlo (MC)…

Machine Learning · Computer Science 2023-07-11 Raziye Kubra Kumrular , Thomas Blumensath

Bayesian imaging inverse problems in astrophysics and cosmology remain challenging, particularly in low-data regimes, due to complex forward operators and the frequent lack of well-motivated priors for non-Gaussian signals. In this paper,…

Instrumentation and Methods for Astrophysics · Physics 2026-02-06 Sébastien Pierre , Erwan Allys , Pablo Richard , Roman Soletskyi , Alexandros Tsouros

Phase retrieval, i.e., the problem of recovering a function from the squared magnitude of its Fourier transform, arises in many applications such as X-ray crystallography, diffraction imaging, optics, quantum mechanics, and astronomy. This…

Image and Video Processing · Electrical Eng. & Systems 2020-12-02 Albert Fannjiang , Thomas Strohmer

We study an inverse problem for the time-dependent Maxwell system in an inhomogeneous and anisotropic medium. The objective is to recover the initial electric field $\mathbf{E}_0$ in a bounded domain $\Omega \subset \mathbb{R}^3$, using…

Numerical Analysis · Mathematics 2025-06-27 Thuy T. Le , Cong B. Van , Trong D. Dang , Loc H. Nguyen

This article presents a theoretical analysis of a one-dimensional heat transfer problem in two layers involving diffusion, advection, internal heat generation or loss linearly dependent on temperature in each layer, and heat generation due…

Fluid Dynamics · Physics 2024-10-28 Guillermo Federico Umbricht , Diana Rubio , Domingo Alberto Tarzia

Inverse transformation optics is introduced, and used to calculate the reflection at the boundary of a transformation medium under consideration. The transformation medium for a practical device is obtained from a two-dimensional (2D)…

Optics · Physics 2014-03-31 Pu Zhang , Yi Jin , Sailing He

The inverse problem we consider is to reconstruct the location and shape of buried obstacles in the lower half-space of an unbounded two-layered medium in two dimensions from phaseless far-field data. A main difficulty of this problem is…

Numerical Analysis · Mathematics 2021-05-26 Long Li , Jiansheng Yang , Bo Zhang , Haiwen Zhang

The inverse scattering method for the Novikov-Veselov equation is studied for a larger class of Schr\"odinger potentials than could be handled previously. Previous work concerns so-called conductivity type potentials, which have a bounded…

Analysis of PDEs · Mathematics 2013-12-03 Michael Music

This paper addresses the inverse source problem for a mixed-type fractional wave-diffusion-wave equation posed in a cylindrical domain. The governing equation involves a time-dependent variable-order fractional derivative, which enables the…

Analysis of PDEs · Mathematics 2026-05-05 Erkinjon Karimov , Muzaffar Toshpulatov

We consider a particular approach to the regularization of the inverse problem of computerized tomography. This approach is based on notions pertaining to Fourier synthesis. It refines previous contributions, in which the preprocessing of…

Optimization and Control · Mathematics 2014-01-30 Pierre Maréchal , Abdelhadi Elasmai

Using the integral representations of the solutions of Schr\"odinger equation, which are the essential ingredients of the Gel'fand-Levitan and Marchenko integral equations of inverse scattering theory, we obtain a general theorem on the…

Mathematical Physics · Physics 2007-06-28 Khosrow Chadan

The famous Fourier theorem states that, under some restrictions, any periodic function (or real world signal) can be obtained as a sum of sinusoids, and hence, a technique exists for decomposing a signal into its sinusoidal components. From…

Numerical Analysis · Computer Science 2008-04-24 Sossio Vergara

We simulate the focusing of a partially-coherent X-ray beam emitted by an undulator in a fourth-generation storage ring performing coherent mode decomposition and wave optics propagation. The focus position is shifted, and its size is…

Computed Tomography (CT) reconstruction of objects with cylindrical symmetry can be performed with a single projection. When the measured rays are parallel, and the axis of symmetry is perpendicular to the optical axis, the data can be…

Medical Physics · Physics 2024-10-15 Kyle M. Champley , Ibrahim Oksuz , Matthew G. Bisbee , Joseph W. Tringe , Brian Maddox

The recently developed globally convergent numerical method for an inverse medium problem for the Helmholtz equation is tested on experimental data. The data were originally collected in the time domain, whereas the method works in the…

Numerical Analysis · Mathematics 2016-10-26 Aleksandr E. Kolesov , Michael V. Klibanov , Loc H. Nguyen , Dinh-Liem Nguyen , Nguyen T. Thanh

In this article, we study the limited angle problem for the weighted X-ray transform. We consider the approximate reconstructions by applying two filtered back projection formulas to the limited data. We prove that each resulted operator…

Mathematical Physics · Physics 2015-12-08 Linh V. Nguyen

We provide a comprehensive study of the convergence of the forward-backward algorithm under suitable geometric conditions, such as conditioning or {\L}ojasiewicz properties. These geometrical notions are usually local by nature, and may…

Optimization and Control · Mathematics 2023-12-25 Guillaume Garrigos , Lorenzo Rosasco , Silvia Villa

The classical Stein--Tomas theorem extends the theory of linear Fourier restriction estimates from smooth manifolds to fractal measures exhibiting Fourier decay. In the multilinear setting, transversality allows for Fourier extension…

Classical Analysis and ODEs · Mathematics 2026-02-11 Itamar Oliveira , Ana E. de Orellana

We consider offsets of a union of convex objects. We aim for a filtration, a sequence of nested cell complexes, that captures the topological evolution of the offsets for increasing radii. We describe methods to compute a filtration based…

Computational Geometry · Computer Science 2015-01-26 Dan Halperin , Michael Kerber , Doron Shaharabani

In this paper, a restricted transverse ray transform acting on vector and symmetric $m$-tensor fields is studied. We developed inversion algorithms using restricted transverse ray transform data to recover symmetric $m$-tensor fields in…

Classical Analysis and ODEs · Mathematics 2024-02-28 Rohit Kumar Mishra , Chandni Thakkar