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arXiv · 2308.12764

Dirichlet-Neumann and Neumann-Neumann Methods for Elliptic Control Problems

Martin Jakob Gander·Liu-Di Lu
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Abstract

We present the Dirichlet-Neumann (DN) and Neumann-Neumann (NN) methods applied to the optimal control problems arising from elliptic partial differential equations (PDEs) under the $H^{-1}$ regularization. We use the Lagrange multiplier approach to derive a forward-backward optimality system with the $L^2$ regularization, and a singular perturbed Poisson equation with the $H^{-1}$ regularization. The $H^{-1}$ regularization thus avoids solving a coupled bi-Laplacian problem, yet the solutions are less regular. The singular perturbed Poisson equation is then solved by using the DN and NN methods, and a detailed analysis is given both in the one-dimensional and two-dimensional case. Finally, we provide some numerical experiments with conclusions.

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Martin Jakob Gander, Liu-Di Lu. 2023-08-24. Dirichlet-Neumann and Neumann-Neumann Methods for Elliptic Control Problems. https://arxiv.org/abs/2308.12764

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