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arXiv · 1605.07823

Compensation for geometric modeling errors by electrode movement in electrical impedance tomography

Nuutti Hyvönen·Helle Majander·Stratos Staboulis
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Abstract

Electrical impedance tomography aims at reconstructing the conductivity inside a physical body from boundary measurements of current and voltage at a finite number of contact electrodes. In many practical applications, the shape of the imaged object is subject to considerable uncertainties that render reconstructing the internal conductivity impossible if they are not taken into account. This work numerically demonstrates that one can compensate for inaccurate modeling of the object boundary in two spatial dimensions by estimating the locations and sizes of the electrodes as a part of a reconstruction algorithm. The numerical studies, which are based on both simulated and experimental data, are complemented by proving that the employed complete electrode model is approximately conformally invariant, which suggests that the obtained reconstructions in mismodeled domains reflect conformal images of the true targets. The numerical experiments also confirm that a similar approach does not, in general, lead to a functional algorithm in three dimensions.

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Nuutti Hyvönen, Helle Majander, Stratos Staboulis. 2016-05-25. Compensation for geometric modeling errors by electrode movement in electrical impedance tomography. https://doi.org/10.1088/1361-6420%2Faa59d0

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