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Related papers: Paraxial diffusion-field retrieval

200 papers

We present Wideband Back-Projection Diffusion, an end-to-end probabilistic framework for approximating the posterior distribution induced by the inverse scattering map from wideband scattering data. This framework produces highly accurate…

Machine Learning · Computer Science 2025-05-20 Borong Zhang , Martín Guerra , Qin Li , Leonardo Zepeda-Núñez

In this paper, we consider the inverse shape problem of recovering small and extended isotropic scatterers with a conductive boundary condition. Here, we assume that the measured far-field data is known at a fixed wave number. We will…

Analysis of PDEs · Mathematics 2023-10-13 Rafael Ceja Ayala , Isaac Harris

Emerging methods of x-ray imaging that capture phase and dark-field effects are equipping medicine with complementary sensitivity to conventional radiography. These methods are being applied over a wide range of scales, from virtual…

Medical Physics · Physics 2023-10-17 T. A. Leatham , D. M. Paganin , K. S. Morgan

We study the diffusion processes of a real scalar field in the presence of the distorsion field induced by a chiral topological defect. The defect modifies the usual Euclidean background geometry into a non-diagonal Riemann-Cartan geometry…

High Energy Physics - Theory · Physics 2022-08-24 Andy Manapany , Leila Moueddene , Bertrand Berche , Sébastien Fumeron

We show that when Brownian motion takes place in a heterogeneous medium, the presence of local forces and transport coefficients leads to deviations from a Gaussian probability distribution that make that the ratio between forward and…

Soft Condensed Matter · Physics 2016-12-21 Paolo Malgaretti , Ignacio Pagonabarraga Miguel J. Rubi

Diffusion-based posterior samplers use pretrained diffusion priors to sample from measurement- or reward-conditioned posteriors, and are widely used for inverse problems. Yet their theoretical behavior remains poorly understood: even with…

Machine Learning · Computer Science 2026-05-08 Matias G. Delgadino , Sebastien Motsch , Advait Parulekar , William Porteous , Sanjay Shakkottai

In this paper, the focus is on the reconstruction of a diffusive field and the localization of the underlying driving sources on arbitrary graphs by observing a significantly smaller subset of vertices of the graph uniformly in time.…

Signal Processing · Electrical Eng. & Systems 2019-07-02 Siddartha Reddy , Sundeep Prabhakar Chepuri

Using diffusion models to solve inverse problems is a growing field of research. Current methods assume the degradation to be known and provide impressive results in terms of restoration quality and diversity. In this work, we leverage the…

Computer Vision and Pattern Recognition · Computer Science 2025-06-02 Charles Laroche , Andrés Almansa , Eva Coupete

We develop a diffusion approximation for systems subject to fast random resetting by small amplitudes. Equivalently, this describes systems with frequent but small catastrophes. We demonstrate the validity of the approximation by computing…

Statistical Mechanics · Physics 2026-02-26 Tobias Galla

Consider the problem of inverse scattering of time-harmonic point sources from an infinite, penetrable rough interface with bounded obstacles buried in the lower half-space, where the interface is assumed to be a local perturbation of a…

Analysis of PDEs · Mathematics 2020-09-02 Jianliang Li , Jiaqing Yang , Bo Zhang

Diffusion on a quenched heterogeneous environment in the presence of bias is considered analytically. The first-passage-time statistics can be applied to obtain the drift and the diffusion coefficient in periodic quenched environments. We…

Statistical Mechanics · Physics 2020-05-06 Takuma Akimoto , Keiji Saito

This paper attempts to undertake the study of Restored Gaussian Blurred Images. by using four types of techniques of deblurring image as Wiener filter, Regularized filter, Lucy Richardson deconvlutin algorithm and Blind deconvlution…

Computer Vision and Pattern Recognition · Computer Science 2010-04-27 Salem Saleh Al-amri , N. V. Kalyankar , Khamitkar S. D

Denoising diffusion models have driven significant progress in the field of Bayesian inverse problems. Recent approaches use pre-trained diffusion models as priors to solve a wide range of such problems, only leveraging inference-time…

Machine Learning · Statistics 2025-02-06 Yazid Janati , Badr Moufad , Mehdi Abou El Qassime , Alain Durmus , Eric Moulines , Jimmy Olsson

This paper is concerned with the inverse problem of reconstructing small and local perturbations of a planar surface using the field interaction between a known plasmonic particle and the planar surface. The aim is to perform a…

Analysis of PDEs · Mathematics 2018-11-21 Habib Ammari , Doo Sung Choi , Sanghyeon Yu

The parametric fluorescence from a nonlinear crystal forms a conical radiation pattern. We measure the angular and spectral distributions of parametric fluorescence in a beta-barium borate crystal pumped by a 405-nm diode laser employing…

Optics · Physics 2013-10-04 Feng-kuo Hsu , Chih-Wei Lai

Iterative phase retrieval algorithms typically employ projections onto constraint subspaces to recover the unknown phases in the Fourier transform of an image, or, in the case of x-ray crystallography, the electron density of a molecule.…

Numerical Analysis · Mathematics 2025-10-20 Veit Elser

Selected theoretical developments in modeling of deposition of submicrometer size (submicron) particles on solid surfaces, with and without surface diffusion, of interest in colloid, polymer, and certain biological systems, are surveyed. We…

Materials Science · Physics 2008-10-16 Vladimir Privman

Paraxial ray tracing procedures have become widely accepted techniques for acoustic models in seismology and underwater acoustics. To date a generic form of these procedures including fluid motion and time dependence has not appeared in the…

Atmospheric and Oceanic Physics · Physics 2009-11-10 David Bergman

Diffusion models represent the state-of-the-art for solving inverse problems such as image restoration tasks. Diffusion-based inverse solvers incorporate a likelihood term to guide prior sampling, generating data consistent with the…

Machine Learning · Computer Science 2026-03-03 Bahareh Tolooshams , Aditi Chandrashekar , Rayhan Zirvi , Abbas Mammadov , Jiachen Yao , Chuwei Wang , Anima Anandkumar

We propose a general theoretical scheme for the investigation of light emitted from nano- and micrometric structures of arbitrary shape and composition. More specifically, the proposed fully three-dimensional approach allows to derive the…

Materials Science · Physics 2009-11-07 M. Pieruccini , S. Savasta , R. Girlanda , R. Iotti , F. Rossi