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DOE OSTI · 1544720

Estimating physics models and quantifying their uncertainty using optimization with a Bayesian objective function

Andrews, Stephen Arthur·Fraser, Andrew Mcleod
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Abstract

This paper reports a verification study for a method that fits functions to sets of data from several experiments simultaneously. The method finds a maximum a posteriori probability (MAP) estimate of a function subject to constraints (e. g., convexity in the study), uncertainty about the estimate, and a quantitative characterization of how data from each experiment constrains that uncertainty. While the present work focuses on a model of the Equation Of State (EOS) of gasses produced by detonating a high explosive, the method can be applied to a wide range of physics processes with either parametric or semi-parametric models. As a verification exercise, a reference EOS is used and artificial experimental data sets are created using numerical integration of ordinary differential equations and pseudo-random noise. The method yields an estimate of the EOS that is close to the reference, and identifies how each experiment most constrains the result.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSBayesianEquation of StateHigh ExplosivesUncertainty Quantificationsemi-parametric

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Andrews, Stephen Arthur, Fraser, Andrew Mcleod. 2019-06-18. Estimating physics models and quantifying their uncertainty using optimization with a Bayesian objective function. https://doi.org/10.1115/1.4043807

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