activity
20152026
most citedModified Tikhonov regularization for identifying several sources

4 citations · 5 across the 5 of their papers we have counts for

collaborators

7 papers

math.AP2026

A note on the convergence of the eigenvalues in a subdomain to the continuous spectrum

Miroslav Bulíček, Bjørn Fredrik Nielsen, Zdeněk Strakoš

The SIGEST paper Nielsen and Strakoš (2024) characterized the spectrum of the preconditioned operator in a bounded open two-dimensional domain $Ω…

math.NA2021

Numerical approximation of the spectrum of self-adjoint continuously invertible operators

Tomáš Gergelits, Bjørn Fredrik Nielsen, Zdeněk Strakoš

This paper deals with the generalized spectrum of continuously invertible linear operators defined on infinite dimensional Hilbert spaces. More precisely, we consider two bounded,…

math.OC20204 cited

Modified Tikhonov regularization for identifying several sources

Ole Løseth Elvetun, Bjørn Fredrik Nielsen

We study whether a modified version of Tikhonov regularization can be used to identify several local sources from Dirichlet boundary data for a prototypical elliptic PDE. This pape…

math.OC2020

A regularization operator for source identification for elliptic PDEs

Ole Løseth Elvetun, Bjørn Fredrik Nielsen

We study a source identification problem for a prototypical elliptic PDE from Dirichlet boundary data. This problem is ill-posed, and the involved forward operator has a significan…

math.AP2020

Generalized spectrum of second order differential operators

Tomáš Gergelits, Bjørn Fredrik Nielsen, Zdeněk Strakoš

We analyze the spectrum of the operator , where denotes the Laplacian and is a symmetric tensor. Our main result shows that this s…

math.CA2017

Regularization of ill-posed point neuron models

Bjørn Fredrik Nielsen

Point neuron models with a Heaviside firing rate function can be ill-posed. That is, the initial-condition-to-solution map might become discontinuous in finite time. If a Lipschitz…