{ "id": "1704.04987", "version": "v1", "published": "2017-04-13T03:33:28.000Z", "updated": "2017-04-13T03:33:28.000Z", "title": "Reconstruction of the Temporal Component in the Source Term of a (Time-Fractional) Diffusion Equation", "authors": [ "Yikan Liu", "Zhidong Zhang" ], "comment": "26 pages", "categories": [ "math.AP", "math-ph", "math.MP", "math.NA" ], "abstract": "In this article, we consider the reconstruction of $\\rho(t)$ in the (time-fractional) diffusion equation $(\\partial_t^\\alpha-\\triangle)u(x,t)=\\rho(t)g(x)$ ($0<\\alpha \\le 1$) by the observation at a single point $x_0$. We are mainly concerned with the situation of $x_0 \\notin$ supp g, which is practically important but has not been well investigated in literature. Assuming the finite sign changes of $\\rho$ and an extra observation interval, we establish the multiple logarithmic stability for the problem based on a reverse convolution inequality and a lower estimate for positive solutions. Meanwhile, we develop a fixed point iteration for the numerical reconstruction and prove its convergence. The performance of the proposed method is illustrated by several numerical examples.", "revisions": [ { "version": "v1", "updated": "2017-04-13T03:33:28.000Z" } ], "analyses": { "subjects": [ "35R11", "35R30", "26A33", "26D10", "65M32" ], "keywords": [ "diffusion equation", "source term", "temporal component", "reconstruction", "time-fractional" ], "note": { "typesetting": "TeX", "pages": 26, "language": "en", "license": "arXiv", "status": "editable" } } }