论文标题
小波神经操作员:参数偏微分方程的神经操作员
Wavelet neural operator: a neural operator for parametric partial differential equations
论文作者
论文摘要
随着传感器技术和图像的巨大进步,我们现在可以访问历史数据的trabytes。但是,如何最好地利用数据来预测未来事件,这是缺乏明确的。在这种情况下,一种可能的替代方法是利用操作员学习算法,该算法直接学习两个功能空间之间的非线性映射;这有助于实时预测自然产生的复杂进化动力学。在这项工作中,我们介绍了一种新型的操作员学习算法,称为小波神经操作员(WNO),该算法将整体内核与小波转换融合在一起。 WNO在功能的时频定位方面利用了小波的优势,并可以准确跟踪空间域中的模式并有效学习功能映射。由于小波在时间/空间和频率上都位于局部,因此WNO可以提供高空间和频率分辨率。这提供了解决复杂问题解决方案中参数依赖性的更细节。在涉及汉堡方程,darcy流,Navier-Stokes方程,Allen-Cahn方程和波流对流方程的各种问题上说明了所提出的WNO的功效和鲁棒性。提出了关于现有操作员学习框架的比较研究。最后,提出的方法用于构建一个数字双胞胎,能够根据可用的历史数据来预测地球的空气温度。
With massive advancements in sensor technologies and Internet-of-things, we now have access to terabytes of historical data; however, there is a lack of clarity in how to best exploit the data to predict future events. One possible alternative in this context is to utilize operator learning algorithm that directly learn nonlinear mapping between two functional spaces; this facilitates real-time prediction of naturally arising complex evolutionary dynamics. In this work, we introduce a novel operator learning algorithm referred to as the Wavelet Neural Operator (WNO) that blends integral kernel with wavelet transformation. WNO harnesses the superiority of the wavelets in time-frequency localization of the functions and enables accurate tracking of patterns in spatial domain and effective learning of the functional mappings. Since the wavelets are localized in both time/space and frequency, WNO can provide high spatial and frequency resolution. This offers learning of the finer details of the parametric dependencies in the solution for complex problems. The efficacy and robustness of the proposed WNO are illustrated on a wide array of problems involving Burger's equation, Darcy flow, Navier-Stokes equation, Allen-Cahn equation, and Wave advection equation. Comparative study with respect to existing operator learning frameworks are presented. Finally, the proposed approach is used to build a digital twin capable of predicting Earth's air temperature based on available historical data.