arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2004.04308math.NAcs.NA
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粗化不确定性空间的学习算法及其在多尺度模拟中的应用

Learning Algorithms for Coarsening Uncertainty Space and Applications to Multiscale Simulations

Zecheng Zhang, Eric Chung, Yalchin Efendiev, Wing Tat Leung

摘要:

在本文中,我们研究和设计随机多尺度偏微分方程的多尺度模拟。对于空间,我们考虑一个粗网格和一个已知的多尺度方法,广义多尺度有限元法(GMsFEM)。为了在每个粗块中获得解的小维度表示,需要对不确定性空间进行分区(粗化)。这种粗化收集提供类似于GMsFEM(或其他选择方法)中概述的多尺度特征的实现。已知该步骤在计算上要求很高,因为它需要许多局部求解和基于它们的聚类。在本文中,我们采取了不同的方法,学习粗化不确定性空间。我们的方法使用深度学习技术来识别不确定性空间中的聚类(粗化)。我们使用卷积神经网络结合一些技术在对手神经网络。我们定义了适当的损失函数在建议的神经网络,其中的损失函数是由几个部分,其中包括与集群和重建的基函数的条款。我们提出了数值结果的渠化渗透率场的例子中的多孔介质中的流动。

英文摘要:

In this paper, we investigate and design multiscale simulations for stochastic multiscale PDEs. As for the space, we consider a coarse grid and a known multiscale method, the Generalized Multiscale Finite Element Method (GMsFEM). In order to obtain a small dimensional representation of the solution in each coarse block, the uncertainty space needs to be partitioned (coarsened). This coarsening collects realizations that provide similar multiscale features as outlined in GMsFEM (or other method of choice). This step is known to be computationally demanding as it requires many local solves and clustering based on them. In this paper, we take a different approach and learn coarsening the uncertainty space. Our methods use deep learning techniques in identifying clusters(coarsening) in the uncertainty space. We use convolutional neural networks combined with some techniques in adversary neural networks. We define appropriate loss functions in the proposed neural networks, where the loss function is composed of several parts that includes terms related to clusters and reconstruction of basis functions. We present numerical results for channelized permeability fields in the examples of flows in porous media.

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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