arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2002.10521math.NAcs.NA
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稀疏观测数据驱动反演模型的物理约束学习

Physics Constrained Learning for Data-driven Inverse Modeling from Sparse Observations

Kailai Xu, Eric Darve

摘要:

深度神经网络(DNN)已被用于对物理量之间的非线性关系进行建模。这些DNN嵌入在由偏微分方程(PDE)描述的物理系统中,并通过最小化损失函数来训练,该损失函数在某些选定的范数中测量预测和观测之间的差异。当只有稀疏观测可用时,该损失函数通常包括PDE约束作为惩罚项。因此,解仅近似满足偏微分方程。然而,惩罚项通常会减慢刚性问题的优化器的收敛速度。我们提出了一种新的方法,在数字上满足PDE约束的同时训练嵌入式DNN。我们开发了一种算法,使显式和隐式数值求解器在反向模式自动微分区分。这允许在统一的框架中计算DNN和PDE求解器的梯度。我们证明了我们的方法具有更快的收敛速度和更好的稳定性,相对刚性的问题相比,惩罚方法。我们的方法允许解决和加速广泛的数据驱动的逆向建模,其中物理约束由PDE描述,需要准确地满足。

英文摘要:

Deep neural networks (DNN) have been used to model nonlinear relations between physical quantities. Those DNNs are embedded in physical systems described by partial differential equations (PDE) and trained by minimizing a loss function that measures the discrepancy between predictions and observations in some chosen norm. This loss function often includes the PDE constraints as a penalty term when only sparse observations are available. As a result, the PDE is only satisfied approximately by the solution. However, the penalty term typically slows down the convergence of the optimizer for stiff problems. We present a new approach that trains the embedded DNNs while numerically satisfying the PDE constraints. We develop an algorithm that enables differentiating both explicit and implicit numerical solvers in reverse-mode automatic differentiation. This allows the gradients of the DNNs and the PDE solvers to be computed in a unified framework. We demonstrate that our approach enjoys faster convergence and better stability in relatively stiff problems compared to the penalty method. Our approach allows for the potential to solve and accelerate a wide range of data-driven inverse modeling, where the physical constraints are described by PDEs and need to be satisfied accurately.

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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