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We explore the possibility for using boundary data to identify sources in elliptic PDEs. Even though the associated forward operator has a large null space, it turns out that box constraints, combined with weighted sparsity regularization,…

Numerical Analysis · Mathematics 2023-03-06 Ole Løseth Elvetun , Bjørn Fredrik Nielsen

This investigation is motivated by PDE-constrained optimization problems arising in connection with electrocardiograms (ECGs) and electroencephalography (EEG). Standard sparsity regularization does not necessarily produce adequate results…

Numerical Analysis · Mathematics 2023-05-25 Ole Løseth Elvetun , Bjørn Fredrik Nielsen

Standard regularization methods typically favor solutions which are in, or close to, the orthogonal complement of the null space of the forward operator/matrix $\mathsf{A}$. This particular biasedness might not be desirable in applications…

Numerical Analysis · Mathematics 2025-09-05 Ole Løseth Elvetun , Bjørn Fredrik Nielsen , Niranjana Sudheer

Source conditions are a key tool in regularisation theory that are needed to derive error estimates and convergence rates for ill-posed inverse problems. In this paper, we provide a recipe to practically compute source condition elements as…

Numerical Analysis · Mathematics 2024-03-01 Martin Benning , Tatiana A. Bubba , Luca Ratti , Danilo Riccio

We obtain bounds on estimation error rates for regularization procedures of the form \begin{equation*} \hat f \in {\rm argmin}_{f\in F}\left(\frac{1}{N}\sum_{i=1}^N\left(Y_i-f(X_i)\right)^2+\lambda \Psi(f)\right) \end{equation*} when $\Psi$…

Statistics Theory · Mathematics 2017-01-04 Guillaume Lecué , Shahar Mendelson

This paper considers the inverse problem of identifying the source term of parabolic equations from sparse boundary measurements. We used data from moving sensors to locate the unknown source term. This work first proves the uniqueness of…

Analysis of PDEs · Mathematics 2026-04-14 Qiling Gu , Wenlong Zhang , Zhidong Zhang

Recovery of the sparsity pattern (or support) of an unknown sparse vector from a small number of noisy linear measurements is an important problem in compressed sensing. In this paper, the high-dimensional setting is considered. It is shown…

Information Theory · Computer Science 2013-02-06 Galen Reeves , Michael Gastpar

We consider multichannel sparse recovery problem where the objective is to find good recovery of jointly sparse unknown signal vectors from the given multiple measurement vectors which are different linear combinations of the same known…

Information Theory · Computer Science 2015-06-11 Esa Ollila

Partial differential equations are central to describing many physical phenomena. In many applications these phenomena are observed through a sensor network, with the aim of inferring their underlying properties. Leveraging from certain…

Information Theory · Computer Science 2017-11-22 John Murray-Bruce , Pier Luigi Dragotti

In this article, the problem of identifying the source term in transport processes given by a complete parabolic equation is studied mathematically from noisy measurements taken at an arbitrary fixed time. The problem is solved analytically…

Analysis of PDEs · Mathematics 2024-08-12 Guillermo Federico Umbricht , Diana Rubio

In this paper we investigate the problem of recovering the source term in an elliptic system from a measurement of the state on a part of the boundary. For the particular interest in reconstructing probably discontinuous sources, we use the…

Numerical Analysis · Mathematics 2020-01-08 Michael Hinze , Tran Nhan Tam Quyen

Source identification problems have multiple applications in engineering such as the identification of fissures in materials, determination of sources in electromagnetic fields or geophysical applications, detection of contaminant sources,…

Numerical Analysis · Mathematics 2021-11-12 Guillermo F. Umbricht , Diana Rubio , Claudio El Hasi

Reconstructing lens potentials and lensed sources can easily become an underconstrained problem, even when the degrees of freedom are low, due to degeneracies, particularly when potential perturbations superimposed on a smooth lens are…

Astrophysics of Galaxies · Physics 2022-07-27 Georgios Vernardos , Leon V. E. Koopmans

We consider the inverse source problem in the parabolic equation, where the unknown source possesses the semi-discrete formulation. Theoretically, we prove that the flux data from any nonempty open subset of the boundary can uniquely…

Numerical Analysis · Mathematics 2022-11-23 Guang Lin , Zecheng Zhang , Zhidong Zhang

This paper is concerned with recovering the solution of a final value problem associated with a parabolic equation involving a non linear source and a non-local term, which to the best of our knowledge has not been studied earlier. It is…

Numerical Analysis · Mathematics 2023-12-20 Subhankar Mondal

The problem of recovering acoustic sources, more specifically monopoles, from point-wise measurements of the corresponding acoustic pressure at a limited number of frequencies is addressed. To this purpose, a family of sparse optimization…

Optimization and Control · Mathematics 2021-03-30 Konstantin Pieper , Bao Quoc Tang , Philip Trautmann , Daniel Walter

The linear inverse source and scattering problems are studied from the perspective of compressed sensing, in particular the idea that sufficient incoherence and sparsity guarantee uniqueness of the solution. By introducing the sensor as…

Data Analysis, Statistics and Probability · Physics 2009-05-19 Albert Fannjiang , Pengchong Yan , Thomas Strohmer

We present a strategy for the recovery of a sparse solution of a common problem in acoustic engineering, which is the reconstruction of sound source levels and locations applying microphone array measurements. The considered task bears…

Optimization and Control · Mathematics 2016-07-04 Laurent Hoeltgen , Michael Breuß , Gert Herold , Ennes Sarradj

In this paper, we study the phase retrieval problem in the situation where the vector to be recovered has an a priori structure that can encoded into a regularization term. This regularizer is intended to promote solutions conforming to…

Optimization and Control · Mathematics 2024-07-24 Jean-Jacques Godeme , Jalal Fadili

The de-facto standard approach of promoting sparsity by means of $\ell_1$-regularization becomes ineffective in the presence of simplex constraints, i.e.,~the target is known to have non-negative entries summing up to a given constant. The…

Methodology · Statistics 2016-05-04 Ping Li , Syama Sundar Rangapuram , Martin Slawski
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