Hybrid neural-network FEM approximation of diffusion coefficient in elliptic and parabolic problems

S Cen, B Jin, Q Quan, Z Zhou - IMA Journal of Numerical …, 2024 - academic.oup.com
In this work we investigate the numerical identification of the diffusion coefficient in elliptic
and parabolic problems using neural networks (NNs). The numerical scheme is based on …

Convergence rates of Tikhonov regularizations for elliptic and parabolic inverse radiativity problems

DH Chen, D Jiang, J Zou - Inverse Problems, 2020 - iopscience.iop.org
We shall study in this paper the convergence rates of the Tikhonov regularized solutions for
the recovery of the radiativities in elliptic and parabolic systems in general dimensional …

Learning river water quality models by l1-weighted regularization

D Nho Hào, D Xuan Hiep… - IMA Journal of Applied …, 2024 - academic.oup.com
We investigate the problem of learning a water quality model (BOD-DO model) from given
data. Assuming that all parameters in the model are constants, we reformulate the problem …

A theoretical study for RTE-based parameter identification problems

J Tang, W Han, B Han - Inverse Problems, 2013 - iopscience.iop.org
This paper provides a theoretical study of reconstructing absorption and scattering
coefficients based on the radiative transport equation (RTE) by using the total variation …

[HTML][HTML] Descent gradient methods for nonsmooth minimization problems in ill-posed problems

PQ Muoi, DN Hào, P Maass, M Pidcock - Journal of Computational and …, 2016 - Elsevier
Descent gradient methods are the most frequently used algorithms for computing
regularizers of inverse problems. They are either directly applied to the discrepancy term …

Convergence rates for total variation regularization of coefficient identification problems in elliptic equations II

DN Hào, TNT Quyen - Journal of Mathematical Analysis and Applications, 2012 - Elsevier
We investigate the convergence rates for total variation regularization of the problem of
identifying (i) the coefficient q in the Neumann problem for the elliptic equation− div (q∇ u) …

An inverse boundary value problem for a second order elliptic equation in a rectangle

YT Mehraliyev, F Kanca - Mathematical Modelling and Analysis, 2014 - Taylor & Francis
In this paper, the inverse problem of finding a coefficient in a second order elliptic equation
is investigated. The conditions for the existence and uniqueness of the classical solution of …

Matrix coefficient identification in an elliptic equation with the convex energy functional method

M Hinze, TNT Quyen - Inverse problems, 2016 - iopscience.iop.org
In this paper we study the inverse problem of identifying the diffusion matrix in an elliptic
PDE from measurements. The convex energy functional method with Tikhonov …

Convergence rates of Tikhonov regularizations for parameter identification in a parabolic-elliptic system

D Jiang, H Feng, J Zou - Inverse Problems, 2012 - iopscience.iop.org
We shall study the convergence rates of the Tikhonov regularizations for the identification of
the diffusivity q (x) in a parabolic–elliptic system. The H 1 regularization and a mixed L p–H 1 …

Finite element approximation of source term identification with TV-regularization

M Hinze, TNT Quyen - Inverse Problems, 2019 - iopscience.iop.org
In this paper we investigate the problem of recovering the source f in the elliptic system from
an observation z of the state u on a part of the boundary, where the functions and j are given …