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NASA NTRS · 20230010526

Combining Data with Physical Knowledge for Uncertainty Quantification in Certification and Reliability Analysis

Abstract

Unifying empirical data with predictive models can enable engineering cost-savings through certification by analysis and reliability-based design. Both concepts require rigorous uncertainty quantification (UQ) and robust understanding and treatment of relevant physics. Combining sampling-based UQ algorithms with high-fidelity simulations creates a computational bottleneck that is often alleviated through the use of machine learning (ML). ML can be used to create computationally efficient surrogates for simulations of complex or high-dimensional physical interactions (e.g., multi-phase interactions associated with melt pools in laser powder bed fusion or spatially-dependent material properties in functionally graded materials). However, negative side effects of ML may include a lack of interpretability and negative correlation between event rarity and simulation accuracy due to a lack of training data. As such, it is important to infuse ML algorithms with physics-based guardrails to provide confidence in their predictions. This talk will provide a brief review of recent NASA research at this intersection of physics-based simulation, ML, and UQ with a focus on certification and reliability analysis.

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BibTeXRIS

Patrick Leser, Will Jenkins, Jacob Hochhalter, Sean Current, Mohannad Elhamod, Marten Thompson, Geoffrey Bomarito, Paul Leser, Jim Warner. Combining Data with Physical Knowledge for Uncertainty Quantification in Certification and Reliability Analysis. https://ntrs.nasa.gov/citations/20230010526

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