arXiv:2410.04193cs.LGcs.NE2024-10

用泰勒展开神经网络加速参数化偏微分方程求解,提升效率与精度。

Parametric Taylor series based latent dynamics identification neural networks

  • 基于泰勒级数与残差网络构建新模型,直接学习低维隐空间的微分方程
  • 训练速度比GPLaSDI快近百倍,保持低于2%的L2误差
  • 无需显式自编码器,适应不同网格尺度,适合追求高效可解释建模的研究者

求解参数化偏微分方程(P-PDEs)虽具实际价值但计算成本高,催生了降阶模型(ROMs)。近年,结合隐空间识别与深度学习(如自编码器)的方法(如LaSDI、gLaSDI、GPLaSDI)在低维隐空间中描述动态系统方面展现出潜力。本文提出一种新的参数化非线性动力学隐空间识别神经网络——P-TLDINets,其核心为基于泰勒展开与残差网络的新结构,用于学习控制降维空间动力学的常微分方程(ODEs)。训练时,基于泰勒的隐动态神经网络(TLDNets)与识别出的方程同步优化,生成更平滑的隐空间。为支持参数化分析,引入基于逆距离加权(IDW)插值的k近邻(KNN)方法,利用局部信息预测识别出的ODE系数。相比基于自编码器的其他方法,P-TLDINets保持模型可解释性,避免构建显式自编码器,不依赖特定网格,结构更轻量,易于训练且泛化能力强。该方法适用于多种网格尺度。相比GPLaSDI和gLaSDI,P-TLDINets训练速度提升近一百倍,同时保持与高保真模型的L2误差低于2%。

原文摘要 · Abstract (English)

Numerical solving parameterised partial differential equations (P-PDEs) is highly practical yet computationally expensive, driving the development of reduced-order models (ROMs). Recently, methods that combine latent space identification techniques with deep learning algorithms (e.g., autoencoders) have shown great potential in describing the dynamical system in the lower dimensional latent space, for example, LaSDI, gLaSDI and GPLaSDI. In this paper, a new parametric latent identification of nonlinear dynamics neural networks, P-TLDINets, is introduced, which relies on a novel neural network structure based on Taylor series expansion and ResNets to learn the ODEs that govern the reduced space dynamics. During the training process, Taylor series-based Latent Dynamic Neural Networks (TLDNets) and identified equations are trained simultaneously to generate a smoother latent space. In order to facilitate the parameterised study, a $k$-nearest neighbours (KNN) method based on an inverse distance weighting (IDW) interpolation scheme is introduced to predict the identified ODE coefficients using local information. Compared to other latent dynamics identification methods based on autoencoders, P-TLDINets remain the interpretability of the model. Additionally, it circumvents the building of explicit autoencoders, avoids dependency on specific grids, and features a more lightweight structure, which is easy to train with high generalisation capability and accuracy. Also, it is capable of using different scales of meshes. P-TLDINets improve training speeds nearly hundred times compared to GPLaSDI and gLaSDI, maintaining an $L_2$ error below $2\%$ compared to high-fidelity models.

降阶模型神经微分方程泰勒展开PDE求解

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。