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DOE OSTI · 2008415

Multifidelity deep operator networks for data-driven and physics-informed problems

Abstract

Operator learning for complex nonlinear systems is increasingly common in modeling multi-physics and multi-scale systems. However, training such high-dimensional operators requires a large amount of expensive, high-fidelity data, either from experiments or simulations. In this work, we present a composite Deep Operator Network (DeepONet) for learning using two datasets with different levels of fidelity to accurately learn complex operators when sufficient high-fidelity data is not available. Additionally, we demonstrate that the presence of low-fidelity data can improve the predictions of physics-informed learning with DeepONets. We demonstrate the new multi-fidelity training in diverse examples, including modeling of the ice-sheet dynamics of the Humboldt glacier, Greenland, using two different fidelity models and also using the same physical model at two different resolutions.

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BibTeXRIS

Howard, Amanda A., Perego, Mauro, Karniadakis, George Em, Stinis, Panos. 2023-09-01. Multifidelity deep operator networks for data-driven and physics-informed problems. https://doi.org/10.1016/j.jcp.2023.112462

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