Visualization of Surface Conductivity Distribution by Conductivity Zones Method

The usage of modification method for direct EIT problem solving is substantiated. The voltages on phantom contour with known current approximation of surface conductivity distribution are calculated. The classical algorithm with Newton–Raphson method for inverse EIT problem solving is shown. That is “refinement” of surface conductivities by results of analysis. The conductivity zones method to reduce the order and time of calculations is described (transition from solution of the equation with 1000 order to 16 times solving the equations with 14 order). The regularization method by A.N. Tykhonov to solve the problem of ill-conditioned derivatives matrices from transfer resistances (nodal voltages) on surface zones conductivities solving the image reconstruction problem in EIT is considered. The algorithm of fast iterative updating regularization algorithm is given. It allows solving the problem by 10–20 steps instead of 1000–1000000 steps of classic algorithm. The expediency of classifier creating to assess the presence or absence of heterogeneity compared to uniform phantom is shown.