bayesian-inference

PyTUQ - UQ Tools and Workflows for Computational Models

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Bayesian Calibration of Fission Gas Diffusivity in Nuclear Fuels Using Multilevel Delayed Acceptance MCMC

We perform multilevel Bayesian calibration of a model for fission gas diffusivity in UO2 nuclear fuel. Specifically, we use a two-level delayed acceptance method that couples a machine learning surrogate for Xe and U diffusivities with a …

Model Error Embedding with Orthogonal Gaussian Processes

Computational models of complex physical systems often rely on simplifying assumptions which inevitably introduce model error, with consequent predictive errors. Given data on model observables, the estimation of parameterized model-error …

Inverse Modeling via Bayesian Inference

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Uncertainty Quantification in Computational Science -- from Physical Models to Neural Networks

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A Novel Framework to Project the Permafrost Fate With Explicit Quantification of Soil Property and Future Climate Uncertainties

Abstract This study develops a novel general framework to project the permafrost fate with rigorous uncertainty quantification to assess dominant sources. Borehole temperature records from three sites in the Russian western Arctic are used to …

Bayesian Calibration of UO2 Creep Rates as a Tool for Accelerated Fuel Qualification

Mechanistic models informed by lower-length-scale simulations have a role to play in accelerating fuel qualification by enabling the use of separate effects tests to reduce uncertainty on model parameters that impact the predictions of in-reactor …

Improving the Quasi-Biennial Oscillation via a Surrogate-Accelerated Multi-Objective Optimization

Abstract Accurate simulation of the quasi-biennial oscillation (QBO) is challenging due to uncertainties in representing convectively generated gravity waves. We develop an end-to-end uncertainty quantification workflow that calibrates these gravity …

Embedded Framework for Model Error Quantification and Propagation

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Spatio-Temporal Surrogate Construction and Calibration of E3SM Land Model

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