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arXiv 2203.00340math.NAcs.NA
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时间分数阶次扩散问题近似的后验误差分析

A posteriori error analysis for approximations of time-fractional subdiffusion problems

Lehel Banjai, Charalambos G. Makridakis

摘要:

在本文中,我们考虑一个子扩散问题,其中分数阶时间导数可以用L1格式或卷积求积来逼近。我们提出了新的解释的数值方案,导致后验误差估计。我们的方法是基于适当的逐点表示的数值方案扰动发展方程和稳定性估计的发展方程。给出了最优阶$L^2(H)$和$L^\infty (H)$范数的后验误差估计。大量的数值实验表明的可靠性和最优性的估计所考虑的计划,以及他们的效率作为错误指标驱动自适应网格选择定位奇点的问题。

英文摘要:

In this paper we consider a sub-diffusion problem where the fractional time derivative is approximated either by the L1 scheme or by Convolution Quadrature. We propose new interpretations of the numerical schemes which lead to a posteriori error estimates. Our approach is based on appropriate pointwise representations of the numerical schemes as perturbed evolution equations and on stability estimates for the evolution equation. A posteriori error estimates in $L^2(H)$ and $L^\infty (H)$ norms of optimal order are derived. Extensive numerical experiments indicate the reliability and the optimality of the estimators for the schemes considered, as well as their efficiency as error indicators driving adaptive mesh selection locating singularities of the problem.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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