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3D EIT Reconstructions from Electrode Data using Direct Inversion D-bar and Calderon Methods

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 نشر من قبل Sarah Hamilton
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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The first numerical implementation of a D-bar method in 3D using electrode data is presented. Results are compared to Calderons method as well as more common TV and smoothness regularization-based methods. D-bar methods are based on tailor-made non-linear Fourier transforms involving the measured current and voltage data. Low-pass filtering in the non-linear Fourier domain is used to stabilize the reconstruction process. D-bar methods have shown great promise in 2D for providing robust real-time absolute and time-difference conductivity reconstructions but have yet to be used on practical electrode data in 3D, until now. Results are presented for simulated data for conductivity and permittivity with disjoint non-radially symmetric targets on spherical domains and noisy voltage data. The 3D D-bar and Calderon methods are demonstrated to provide comparable quality to their 2D CGO counterparts, and hold promise for real-time reconstructions.



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