38
2 Voxel-Based Inversion Via Set-Theoretic Estimation
3 mm
3 mm
z
y
0
0
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0
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y
x
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Fig. 2.10 A surface-breaking checkerboard
Fig. 2.11 Reconstruction of
the middle row and column of
the surface-breaking
checkerboard
y
x
-0.01
-0.01
0.00
-1.00
-0.01
-1.00
0
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are to be determined during the reconstruction. This, together with the fact that the
checkerboard scene contains high spatial-frequencies, suggests that we use a 31×31
raster scan for the receiver probe, rather than the 16 × 16 scan that was used in the
preceding examples, but covering the same area. The resolution of the receiver scan
was thereby improved to 0.2 over 0.4 mm.
When we do this we get an excellent reconstruction; the top layer is reconstructed
exactly (zero anomalous conductivity), and the reconstruction of the middle row and
column of the bottom layer are shown in Fig. 2.12.