Research Of Electrical Resistance Tomography Based On Pattern Transition

Electrical Resistance Tomography(ERT) is a new interdisciplinary tomography based on the circuit, new electrical technology, medicine and biology. ERT have advantages such as non-invasive, multi-point measurement, no radiation, on line measurement, simple structure, low cost and fast response. ERT give the predictable information be helpful to early diagnosis and the diagnosis process does not cause radiation to patients and injuries. In recent years, ERT has begun to applied to the medical field. ERT is one of the hot researches.Based on 985 items, the thesis researches the ERT technology by the numbers. On obverse question, the research analyze the structure of electrodes and infection of ERT quality by current injection model in depth, considering imaging speed and the quality of the reconstructed image, the thesis select the 32 electrodes and near current injection mode which have the best imaging.The thesis study the finite element meshing method,improve finite element meshing method and let finite element unit more imperceptible based on the original triangulation. Experimental results show that the method get better imaging results.The thesis get the rule of border voltage change when the conductance distribution in electric field change through the deep analysis of affection of border voltage in electric field and the rule of border voltage when the conductance distribution in electric field change, such as the increase of the target area and location migration.On inverse question, the thesis advance ERT methods based on the Pattern Transition (PT) Optimized algorithm. PT algorithm will be applied to optimization of electrical resistance tomography image reconstruction process. Compared with Newton's algorithm, the experimental results show that PT algorithm improve image quality and get better image reconstruction performance.The thesis develops the ERT simulation platform based on Matlab7.01 and realize the finite element meshing method PT algorithm. The thesis do a lot of experiments including structure of the electrodes, current injection model, the finite element meshing method and field analysis and image reconstruction etc. The results of conductivity distribution of the corresponding show the method given by this thesis is effective and superior.