The Application Of The Discrete Regularization Method To Underground Radio Wave Tomography

Along with the improvment of the level of mechanization of mining coal, the degree of requirement on the detection of crytic and abnormity structure in working panels and other goelogical blocks influencing normal mining of coal layer, is moer and more higher. To this end, underground radio-wave penetration method has been served as extremely important role. The algebraic reconstruction technique (ART) and simultaneous iterative reconstruction technique (SIRT) are usually accepted for data processing and explanation. Principly, they belong to the embryonic form of regularization technique without constrations, and their inversion results still could not meet the practical needs of mining coal completely.In view of the fact that the above image reconstruction is seriously rank deficient problem with constrations, this thesis is devoted to employ discrete Tikhonov regularization method with constrations for overcome these di-ficulties according to the features of underground radio-wave penetration. The emphasis is focused on two aspects:(1) the automatic generation of discrete mesh and penetration eqautions; (2) the numerical realization of constrained Tikhonov regularization method including the transformation from the unconstraint case to the constraint case, the standardization of related constrained least-squares for directly calling a MATLAB function named LSQLIN to solve it, and the discussion about the selectin of a reasonable regularization parameter in the constrained case.A great mount of numerical experiments is also made to compare the efficiency and numerical stability of several methods such as ART and Tikhonov regularization method with and without constraints. The results indicate that the new algorithm proposed in this paper is more accurate and more stable than ART and unconstrained Tikhonov regularization method.