在改进的有限元模型上实现一种较严格的动态电阻抗断层成象算法

Implementing A Relatively Rigorous Algorithm of Dynamic EIT Problem on The Modified FEM Model

对一种较为严格的图像重构算法——广义逆法进行了推导，并在计算机有限元模型上实现了该算法，重构出了反映阻抗变化量的图像（即动态成像），并根据阻抗重构问题的特点，改进了现有的有限元计算机重构模型，在改进模型上实现了广义逆法。改进的模型与原有模型相比，其正向矩阵的病态性得到较大的改善。从重构结果上看，在改进模型上的广义逆法与现有算法——等位线法相比，成像定位更准确、图像更清晰，能较好的重构出阻抗分布复杂的模型，噪声性能也优于等位线法。

We deduced a relatively rigorous algorithm of dynamic EIT problem general inverse algorithm,and implemented it on the computer FEM model.Images which can show the changing of the resistivity(i.e.dynamic resistivity images)were gained.Also we modified the ordinary FEM model according to the characteristic of the EIT problem and implemented the general inverse algorithm on the modifed model.The ill posed condition of the forward matrix based on the modified model was fairly improved.It can be seen from the results that the general inverse algorithm with modified FEM model is an algorithm better than the back projection algorithm in terms of object locating,image definition,and the ability of dealing with complex object and noise.