Deep Learning is having a remarkable impact on the design of Reduced Order Models (ROMs) for Partial Differential Equations (PDEs), where it is exploited as a powerful tool for tackling complex problems for which classical methods might fail. In this respect, deep autoencoders play a fundamental role, as they provide an extremely flexible tool for reducing the dimensionality of a given problem by leveraging on the nonlinear capabilities of neural networks. Indeed, starting from this paradigm, several successful approaches have already been developed, which are here referred to as Deep Learning-based ROMs (DL-ROMs). Nevertheless, when it comes to stochastic problems parameterized by random fields, the current understanding of DL-ROMs is mostly based on empirical evidence: in fact, their theoretical analysis is currently limited to the case of PDEs depending on a finite number of (deterministic) parameters. The purpose of this work is to extend the existing literature by providing some theoretical insights about the use of DL-ROMs in the presence of stochasticity generated by random fields. In particular, we derive explicit error bounds that can guide domain practitioners when choosing the latent dimension of deep autoencoders. We evaluate the practical usefulness of our theory by means of numerical experiments, showing how our analysis can significantly impact the performance of DL-ROMs.

深度学习在设计偏微分方程的降阶模型（ROMs）方面产生了显著影响，特别是在处理复杂问题以及基于随机领域参数化的随机问题中，深度自动编码器作为一种灵活工具提供了降低问题维数的手段，该研究通过理论分析为深度学习基于ROMs在随机领域参数化问题中的应用提供了一些实用的指导方法，这对于领域专家在选择深度自动编码器的潜在维度时具有重要意义，并通过数值实验证明了理论分析对于DL-ROMs性能的重大影响。

深度自动编码器的潜在维度在由随机场参数化的PDE的降阶建模中的应用