English
Related papers

Related papers: Reconstructing a point source from diffusion fluxe…

200 papers

A low diffusive flux difference splitting based kinetic scheme is developed based on a discrete velocity Boltzmann equation, with a novel three velocity model. While two discrete velocities are used for upwinding, the third discrete…

Fluid Dynamics · Physics 2024-10-01 Shrinath. K. S , Maruthi. N. H , S. V. Raghurama Rao , Veeredhi Vasudeva Rao

In this work the authors consider the recovery of the point source in the heat equation. The used data is the sparse boundary measurements. The uniqueness theorem of the inverse problem is given. After that, the numerical reconstruction is…

Numerical Analysis · Mathematics 2025-02-06 Qiling Gu , Wenlong Zhang , Zhidong Zhang

We consider simultaneously identifying the membership and locations of point sources that are convolved with different low-pass point spread functions, from the observation of their superpositions. This problem arises in three-dimensional…

Information Theory · Computer Science 2015-04-24 Yuanxin Li , Yuejie Chi

Source apportionment analysis, which aims to quantify the attribution of observed concentrations of multiple air pollutants to specific sources, can be formulated as a non-negative matrix factorization (NMF) problem. However, NMF is…

Statistics Theory · Mathematics 2025-10-08 Bora Jin , Abhirup Datta

We present an algorithm capable of detecting diffuse, dim sources of any size in an astronomical image. These sources often defeat traditional methods for source finding, which expand regions around points of high intensity. Extended…

Instrumentation and Methods for Astrophysics · Physics 2016-01-05 T. Butler-Yeoman , M. Frean , C. P. Hollitt , D. W. Hogg , M. Johnston-Hollitt

A common challenge in the natural sciences is to disentangle distinct, unknown sources from observations. Examples of this source separation task include deblending galaxies in a crowded field, distinguishing the activity of individual…

Machine Learning · Computer Science 2025-10-08 Sebastian Wagner-Carena , Aizhan Akhmetzhanova , Sydney Erickson

Detection of point sources in images is a fundamental operation in astrophysics, and is crucial for constraining population models of the underlying point sources or characterizing the background emission. Standard techniques fall short in…

Instrumentation and Methods for Astrophysics · Physics 2018-02-28 Tansu Daylan , Stephen K. N. Portillo , Douglas P. Finkbeiner

We analyze the evolution of the distribution, both in the phase space and in the physical space, of inertial particles released by a spatially-localized (punctual) source and advected by an incompressible flow. The difference in mass…

Fluid Dynamics · Physics 2019-02-13 Marco Martins Afonso , Sílvio M. A. Gama

In this paper we consider the problem of localizing a set of broadband sources from a finite window of measurements. In the case of narrowband sources this can be reduced to the problem of spectral line estimation, where our goal is simply…

Signal Processing · Electrical Eng. & Systems 2022-10-24 Coleman DeLude , Rakshith Sharma , Santhosh Karnik , Christopher Hood , Mark Davenport , Justin Romberg

The diffusion of chiral active Brownian particles in three-dimensional space is studied analytically, by consideration of the corresponding Fokker-Planck equation for the probability density of finding a particle at position…

Statistical Mechanics · Physics 2016-12-21 Francisco J. Sevilla

In this paper, we introduce a frequency-domain approach to extract information on the trajectory of a moving point source. The method hinges on the analysis of multi-frequency near-field data recorded at one and sparse observation points in…

Numerical Analysis · Mathematics 2025-08-25 Guanqiu Ma , Hongxia Guo , Guanghui Hu

This paper is devoted to the inverse problem of recovering the unknown distributed flux on an inaccessible part of boundary using measurement data on the accessible part. We establish and verify a variational source condition for this…

Analysis of PDEs · Mathematics 2019-02-20 De-Han Chen , Yousept Irwin , Jun Zou

This paper presents a novel formula for the transition density of the Brownian motion on a sphere of any dimension and discusses an algorithm for the simulation of the increments of the spherical Brownian motion based on this formula. The…

Statistical Mechanics · Physics 2025-04-01 Aleksandar Mijatović , Veno Mramor , Gerónimo Uribe Bravo

As a popular representation of 3D data, point cloud may contain noise and need to be filtered before use. Existing point cloud filtering methods either cannot preserve sharp features or result in uneven point distribution in the filtered…

Computer Vision and Pattern Recognition · Computer Science 2022-01-19 Shuaijun Chen , Jinxi Wang , Wei Pan , Shang Gao , Meili Wang , Xuequan Lu

Conventional approaches for simulating steady-state distributions of particles under diffusive and advective transport at high P\'eclet numbers involve solving the diffusion and advection equations in at least two dimensions. Here, we…

The reconstruction of unsteady flow fields from limited measurements is a challenging and crucial task for many engineering applications. Machine learning models are gaining popularity for solving this problem due to their ability to learn…

Fluid Dynamics · Physics 2026-01-09 Marc Amorós-Trepat , Luis Medrano-Navarro , Qiang Liu , Luca Guastoni , Nils Thuerey

We introduce a novel, training-free system for reconstructing, understanding, and rendering 3D indoor scenes from a sparse set of unposed RGB images. Unlike traditional radiance field approaches that require dense views and per-scene…

Computer Vision and Pattern Recognition · Computer Science 2026-03-24 Jiatong Xia , Lingqiao Liu

Point source localisation is generally modelled as a Lasso-type problem on measures. However, optimisation methods in non-Hilbert spaces, such as the space of Radon measures, are much less developed than in Hilbert spaces. Most numerical…

Optimization and Control · Mathematics 2024-02-14 Tuomo Valkonen

The problem of mass diffusion in layered systems has relevance to applications in different scientific disciplines, e.g., chemistry, material science, soil science, and biomedical engineering. The mathematical challenge in these type of…

Statistical Mechanics · Physics 2020-10-28 Oded Farago

We study the inverse random source problem for the time-space fractional diffusion equation driven by fractional Brownian motion with Hurst index $H\in(0,1)$. With the aid of a novel estimate, by using the operator approach we propose…

Probability · Mathematics 2021-06-03 Daxin Nie , Weihua Deng