{ "id": "1505.02566", "version": "v1", "published": "2015-05-11T11:07:40.000Z", "updated": "2015-05-11T11:07:40.000Z", "title": "Reconstruction of the solution and the source of hyperbolic equations from boundary measurements: mixed formulations", "authors": [ "Nicolae Cindea", "Arnaud Munch" ], "comment": "arXiv admin note: substantial text overlap with arXiv:1502.00114", "categories": [ "math.OC" ], "abstract": "We introduce a direct method allowing to solve numerically inverse type problems for linear hyperbolic equations. We first consider the reconstruction of the full solution of the wave equation posed in $\\Omega\\times (0,T)$ - $\\Omega$ a bounded subset of $\\mathbb{R}^N$ - from a partial boundary observation. We employ a least-squares technique and minimize the $L^2$-norm of the distance from the observation to any solution. Taking the hyperbolic equation as the main constraint of the problem, the optimality conditions are reduced to a mixed formulation involving both the state to reconstruct and a Lagrange multiplier. Under usual geometric optic conditions, we show the well-posedness of this mixed formulation (in particular the inf-sup condition) and then introduce a numerical approximation based on space-time finite elements discretization. We prove the strong convergence of the approximation and then discuss several examples for $N=1$ and $N=2$. The problem of the reconstruction of both the state and the source term is also addressed.", "revisions": [ { "version": "v1", "updated": "2015-05-11T11:07:40.000Z" } ], "analyses": { "keywords": [ "mixed formulation", "boundary measurements", "reconstruction", "space-time finite elements discretization", "usual geometric optic conditions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150502566C" } } }