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Related papers: Reconstructing a point source from diffusion fluxe…

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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

Consider the geometric inverse problem: There is a set of delta-sources in spacetime that emit waves travelling at unit speed. If we know all the arrival times at the boundary cylinder of the spacetime, can we reconstruct the space, a…

Differential Geometry · Mathematics 2023-08-09 Maarten V. de Hoop , Joonas Ilmavirta , Matti Lassas , Teemu Saksala

In this work we investigate an inverse problem of recovering point sources and their time-dependent strengths from {a posteriori} partial internal measurements in a subdiffusion model which involves a Caputo fractional derivative in time…

Analysis of PDEs · Mathematics 2024-12-12 Kuang Huang , Bangti Jin , Yavar Kian , Georges Sadaka , Zhi Zhou

Single-image point cloud reconstruction must infer complete 3D geometry, including occluded parts, from a single RGB image. While diffusion-based reconstructors achieve high accuracy, they typically require many denoising iterations,…

Computer Vision and Pattern Recognition · Computer Science 2026-04-28 Yuta Baba , Keiji Yanai

A study of the diffusion of a passive Brownian particle on the surface of a sphere and subject to the effects of an external potential, coupled linearly to the probability density of the particle's position, is presented through a numerical…

Statistical Mechanics · Physics 2021-08-31 Adriano Valdés Gómez , Francisco J. Sevilla

The reconstruction of real-world surfaces is on high demand in various applications. Most existing reconstruction approaches apply 3D scanners for creating point clouds which are generally sparse and of low density. These points clouds will…

Computer Vision and Pattern Recognition · Computer Science 2021-03-01 Rajat Sharma , Tobias Schwandt , Christian Kunert , Steffen Urban , Wolfgang Broll

This paper introduces a multi-frequency factorization method for imaging a time-dependent source, specifically to recover its spatial support and the associated excitation instants. Using far-field data from two opposite directions, we…

Numerical Analysis · Mathematics 2026-04-28 Guanqiu Ma , Hongxia Guo , Guanghui Hu

We present the starblade algorithm, a method to separate superimposed point sources from auto-correlated, diffuse flux using a Bayesian model. Point sources are assumed to be independent from each other and to follow a power-law brightness…

Instrumentation and Methods for Astrophysics · Physics 2018-08-07 Jakob Knollmüller , Philipp Frank , Torsten A. Enßlin

With the development of 3D sensing technologies, point clouds have attracted increasing attention in a variety of applications for 3D object representation, such as autonomous driving, 3D immersive tele-presence and heritage reconstruction.…

Computer Vision and Pattern Recognition · Computer Science 2019-01-01 Junkun Qi , Wei Hu , Zongming Guo

3D motion estimation including scene flow and point cloud registration has drawn increasing interest. Inspired by 2D flow estimation, recent methods employ deep neural networks to construct the cost volume for estimating accurate 3D flow.…

Computer Vision and Pattern Recognition · Computer Science 2022-05-25 Xiaodong Gu , Chengzhou Tang , Weihao Yuan , Zuozhuo Dai , Siyu Zhu , Ping Tan

Equation-free approaches have been proposed in recent years for the computational study of multiscale phenomena in engineering problems where evolution equations for the coarse-grained, system-level behavior are not explicitly available. In…

Dynamical Systems · Mathematics 2007-05-23 Yu Zou , Ioannis G. Kevrekidis , Roger G. Ghanem

In this article, we discuss the numerical solution of diffusion equations on random surfaces within the isogeometric framework. We describe in detail, how diffusion problems on random surfaces can be modelled and how quantities of interest…

Numerical Analysis · Mathematics 2022-04-28 Wei Huang , Michael Multerer

We present a novel method for reconstructing parametric, volumetric, multi-story building models from unstructured, unfiltered indoor point clouds by means of solving an integer linear optimization problem. Our approach overcomes…

Graphics · Computer Science 2019-07-02 Sebastian Ochmann , Richard Vock , Reinhard Klein

Projection Pursuit is a classic exploratory technique for finding interesting projections of a dataset. We propose a method for recovering projections containing either Imbalanced Clusters or a Bernoulli-Rademacher distribution using a…

Machine Learning · Computer Science 2025-07-01 Martin Eppert , Satyaki Mukherjee , Debarghya Ghoshdastidar

This paper investigates an inverse source problem for space-time fractional diffusion equations from a posteriori interior measurements. The uniqueness result is established by the memory effect of fractional derivatives and the unique…

Numerical Analysis · Mathematics 2025-10-24 Kai Yu , Zhiyuan Li , Yikan Liu

The movement of a particle described by Brownian motion is quantified by a single parameter, $D$, the diffusion constant. The estimation of $D$ from a discrete sequence of noisy observations is a fundamental problem in biological single…

Subcellular Processes · Quantitative Biology 2016-04-13 Peter K. Relich , Mark J. Olah , Patrick J. Cutler , Keith A. Lidke

From the exact single step evolution equation of the two-point correlation function of a particle distribution subjected to a stochastic displacement field $\bu(\bx)$, we derive different dynamical regimes when $\bu(\bx)$ is iterated to…

Statistical Mechanics · Physics 2011-11-10 Andrea Gabrielli , Fabio Cecconi

We study the inverse problem of recovering a spatially dependent variable order in a time-fractional diffusion model from the boundary flux measurement generated by a single boundary excitation. It arises in the identification of…

Analysis of PDEs · Mathematics 2026-02-27 Jiho Hong , Bangti Jin , Yavar Kian

Motivated by recent work on approximation of diffusion equations by deterministic interacting particle systems, we develop a nonlocal approximation for a range of linear and nonlinear diffusion equations and prove convergence of the method…

Analysis of PDEs · Mathematics 2024-04-05 Katy Craig , Matt Jacobs , Olga Turanova

This paper concerns the inverse source scattering problems of recovering random sources for acoustic and elastic waves. The underlying sources are assumed to be random functions driven by an additive white noise. The inversion process aims…

Numerical Analysis · Mathematics 2024-12-10 Yan Chang , Yukun Guo , Zhipeng Yang , Yue Zhao