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arXiv · 1802.03636

Probabilistic modelling and reconstruction of strain

Carl Jidling·Johannes Hendriks·Niklas Wahlström·Alexander Gregg·Thomas B. Schön·Christopher Wensrich·Adrian Wills
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Abstract

This paper deals with modelling and reconstruction of strain fields, relying upon data generated from neutron Bragg-edge measurements. We propose a probabilistic approach in which the strain field is modelled as a Gaussian process, assigned a covariance structure customised by incorporation of the so-called equilibrium constraints. The computational complexity is significantly reduced by utilising an approximation scheme well suited for the problem. We illustrate the method on simulations and real data. The results indicate a high potential and can hopefully inspire the concept of probabilistic modelling to be used within other tomographic applications as well.

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Carl Jidling, Johannes Hendriks, Niklas Wahlström, Alexander Gregg, Thomas B. Schön, Christopher Wensrich, Adrian Wills. 2018-02-10. Probabilistic modelling and reconstruction of strain. https://doi.org/10.1016/j.nimb.2018.08.051

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