arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2011.11761cs.LGeess.SPphysics.class-phphysics.data-anstat.ML
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用人工神经网络求解多尺度计算力学统计反问题

A robust solution of a statistical inverse problem in multiscale computational mechanics using an artificial neural network

Univ Gustave Eiffel(古斯塔夫·埃菲尔大学)

Florent Pled, Christophe Desceliers, Tianyu Zhang

摘要:

利用基于人工神经网络的机器学习方法对随机非均质材料的表观弹性性质进行了反演。所提出的基于神经网络的识别方法需要构建一个数据库,从该数据库中可以训练人工神经网络来学习随机顺应性场的先验随机模型的超参数与自组织多尺度计算模型的一些相关感兴趣量之间的非线性关系。首先从计算模型生成由输入数据和目标数据组成的初始数据库,通过使用非参数统计相对于目标数据调节输入数据,从该初始数据库推导出处理后的数据库。然后从每个初始和处理的数据库中训练两层和三层前馈人工神经网络,以构建超参数(网络输出)和感兴趣的量(网络输入)之间的非线性映射的代数表示。训练的人工神经网络的性能进行了分析,在均方误差,线性回归拟合和网络输出和目标之间的概率分布的两个数据库。最后提出了一种输入随机向量的自组织概率模型,以考虑网络输入的不确定性,并对网络输出相对于输入不确定性水平进行鲁棒性分析。所提出的基于神经网络的识别方法的能力,以有效地解决潜在的统计逆问题,通过两个数值例子内的二维平面应力线弹性的框架内开发,即对通过计算模拟获得的合成数据的第一验证示例和对通过数字图像监控的物理实验获得的真实实验数据的第二应用示例真实异质生物材料(牛皮质骨)的相关性。

英文摘要:

This work addresses the inverse identification of apparent elastic properties of random heterogeneous materials using machine learning based on artificial neural networks. The proposed neural network-based identification method requires the construction of a database from which an artificial neural network can be trained to learn the nonlinear relationship between the hyperparameters of a prior stochastic model of the random compliance field and some relevant quantities of interest of an ad hoc multiscale computational model. An initial database made up with input and target data is first generated from the computational model, from which a processed database is deduced by conditioning the input data with respect to the target data using the nonparametric statistics. Two-and three-layer feedforward artificial neural networks are then trained from each of the initial and processed databases to construct an algebraic representation of the nonlinear mapping between the hyperparameters (network outputs) and the quantities of interest (network inputs). The performances of the trained artificial neural networks are analyzed in terms of mean squared error, linear regression fit and probability distribution between network outputs and targets for both databases. An ad hoc probabilistic model of the input random vector is finally proposed in order to take into account uncertainties on the network input and to perform a robustness analysis of the network output with respect to the input uncertainties level. The capability of the proposed neural network-based identification method to efficiently solve the underlying statistical inverse problem is illustrated through two numerical examples developed within the framework of 2D plane stress linear elasticity, namely a first validation example on synthetic data obtained through computational simulations and a second application example on real experimental data obtained through a physical experiment monitored by digital image correlation on a real heterogeneous biological material (beef cortical bone).

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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