Iterative computational identification of a spacewise dependent the source in a parabolic equations

Petr N. Vabishchevich

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arXiv · 1604.04443

Iterative computational identification of a spacewise dependent the source in a parabolic equations

Petr N. Vabishchevich

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Abstract

Coefficient inverse problems related to identifying the right-hand side of an equation with use of additional information is of interest among inverse problems for partial differential equations. When considering non-stationary problems, tasks of recovering the dependence of the right-hand side on time and spatial variables can be treated as independent. These tasks relate to a class of linear inverse problems, which sufficiently simplifies their study. This work is devoted to a finding the dependence of right-hand side of multidimensional parabolic equation on spatial variables using additional observations of the solution at the final point of time - the final overdetermination. More general problems are associated with some integral observation of the solution on time - the integral overdetermination. The first method of numerical solution of inverse problems is based on iterative solution of boundary value problem for time derivative with non-local acceleration. The second method is based on the known approach with iterative refinement of desired dependence of the right-hand side on spacial variables. Capabilities of proposed methods are illustrated by numerical examples for model two-dimensional problem of identifying the right-hand side of a parabolic equation. The standard finite-element approximation on space is used, the time discretization is based on fully implicit two-level schemes.

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Petr N. Vabishchevich. 2016-04-15. Iterative computational identification of a spacewise dependent the source in a parabolic equations. https://arxiv.org/abs/1604.04443

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