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Improved surrogates in inertial confinement fusion with manifold and cycle consistencies.

ABSTRACT: Neural networks have become the method of choice in surrogate modeling because of their ability to characterize arbitrary, high-dimensional functions in a data-driven fashion. This paper advocates for the training of surrogates that are 1) consistent with the physical manifold, resulting in physically meaningful predictions, and 2) cyclically consistent with a jointly trained inverse model; i.e., backmapping predictions through the inverse results in the original input parameters. We find that these two consistencies lead to surrogates that are superior in terms of predictive performance, are more resilient to sampling artifacts, and tend to be more data efficient. Using inertial confinement fusion (ICF) as a test-bed problem, we model a one-dimensional semianalytic numerical simulator and demonstrate the effectiveness of our approach.

SUBMITTER: Anirudh R

PROVIDER: S-EPMC7211929 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Improved surrogates in inertial confinement fusion with manifold and cycle consistencies.

Anirudh Rushil R Thiagarajan Jayaraman J JJ Bremer Peer-Timo PT Spears Brian K BK

Proceedings of the National Academy of Sciences of the United States of America 20200420 18

Neural networks have become the method of choice in surrogate modeling because of their ability to characterize arbitrary, high-dimensional functions in a data-driven fashion. This paper advocates for the training of surrogates that are 1) consistent with the physical manifold, resulting in physically meaningful predictions, and 2) cyclically consistent with a jointly trained inverse model; i.e., backmapping predictions through the inverse results in the original input parameters. We find that t ...[more]

PMID: 32312816

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