Abstract：The use of electrical capacitance tomography technology to solve image reconstruction problems is a nonlinear problem. Usually, only the linear part of the sensitivity coefficients is preserved in the derivation process of sensitivity. However, the neglected nonlinear part also contains important imaging information. In order to improve the accuracy of image reconstruction, a second-order hybrid sensitivity matrix is established based on the mathematical definition of the second-order sensitivity coefficient, combined with fuzzy C-means clustering algorithm and electric field center line theory, and the matrix is introduced into the Landweber algorithm, proposing the second-order hybrid Landweber algorithm. Finally, simulation and static experiments are conducted and compared with the traditional Tikhonov and first-order Landweber algorithm, the results show that the second-order hybrid sensitivity matrix can improve the image reconstruction accuracy.
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2024, Vol. 45 
