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arXiv 1209.4974math.NAcs.NAmath.APmath.PR
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随机势椭圆方程异构多尺度格式的校正子分析

Corrector Analysis of a Heterogeneous Multi-scale Scheme for Elliptic Equations with Random Potential

Columbia University(哥伦比亚大学);Ecole Normale Supérieure(巴黎高等师范学院)

Guillaume Bal, Wenjia Jing

AI总结:

本文分析异构多尺度一阶有限元方法求解随机势椭圆方程时随机涨落的正确性,发现当细尺度问题覆盖整个区域时算法正确估计涨落,而仅覆盖部分区域时短程相互作用下方差放大,长程相互作用下无放大。

摘要:

本文分析了应用异构多尺度一阶有限元方法求解具有随机势的椭圆方程所获得的随机涨落。我们证明,当在覆盖整个计算域的子集上求解适当的细尺度问题时,异构多尺度算法能正确估计这些随机涨落。然而,当细尺度问题在不覆盖整个区域的补片上求解时,随机涨落可能被准确估计也可能不被准确估计。在短程相互作用的随机势情况下,随机涨落的方差随补片覆盖介质比例倒数的增大而放大。而在长程相互作用的随机势情况下,这种放大不会发生,随机涨落被正确捕获,与补片的(宏观)尺寸无关。这些结果与作者在一维背景下对更一般方程得到的结果一致,并为使用更粗糙(因而计算强度更低)算法导致的精度损失提供了指示。

英文摘要:

This paper analyzes the random fluctuations obtained by a heterogeneous multi-scale first-order finite element method applied to solve elliptic equations with a random potential. We show that the random fluctuations of such solutions are correctly estimated by the heterogeneous multi-scale algorithm when appropriate fine-scale problems are solved on subsets that cover the whole computational domain. However, when the fine-scale problems are solved over patches that do not cover the entire domain, the random fluctuations may or may not be estimated accurately. In the case of random potentials with short-range interactions, the variance of the random fluctuations is amplified as the inverse of the fraction of the medium covered by the patches. In the case of random potentials with long-range interactions, however, such an amplification does not occur and random fluctuations are correctly captured independent of the (macroscopic) size of the patches. These results are consistent with those obtained by the authors for more general equations in the one-dimensional setting and provide indications on the loss in accuracy that results from using coarser, and hence less computationally intensive, algorithms.

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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