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arXiv · 2504.02072

A balancing domain decomposition by constraints preconditioner for a hybridizable discontinuous Galerkin discretization of an elliptic optimal control problem

Sijing Liu·Jinjin Zhang
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Abstract

We consider a hybridizable discontinuous Galerkin (HDG) method for an elliptic distributed optimal control problem and we propose a balancing domain decomposition by constraints (BDDC) preconditioner to solve the discretized system. We establish an error estimate of the HDG methods with explicit tracking of a regularization parameter $\beta$. We observe that the BDDC preconditioner is robust with respect to $\beta$. Numerical results are shown to support our findings.

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Sijing Liu, Jinjin Zhang. 2025-04-02. A balancing domain decomposition by constraints preconditioner for a hybridizable discontinuous Galerkin discretization of an elliptic optimal control problem. https://arxiv.org/abs/2504.02072

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