基于矩阵预处理和BPT-SIRT非线性加权反演成像法  

The Method of Inversion Imaging Based on Matrix Pretreatment and BPT-SIRT Nonlinear Weighted

作　　者：袁野[1] 黄晓寒[1] 王仲刚[1] 张彧[1] 江正 

机构地区：[1]后勤工程学院军事土木工程系,重庆401311 [2]装备发展部078工程指挥部,海南文昌610041

出　　处：《CT理论与应用研究（中英文）》2017年第1期53-62,共10页Computerized Tomography Theory and Applications

基　　金：后勤工程学院青年科研基金资助项目(YQ15-420401)

摘　　要：为提高弹性波CT层析成像中反演成像的质量,同时考虑到CT走时方程中系数矩阵的病态性和BPT-SIRT算法重建图像质量较低的问题,提出基于主元加权预处理和对BPT-SIRT算法加权的方法。该方法对BPT得到的初始迭代值进行加权预处理,在CT走时方程中的系数矩阵主元上叠加一个权值,再通过非线性的指数加权函数对射线路径矩阵中的元素进行加权。通过数值模拟和预制含缺陷的钢管混凝土试件对该方法进行验证,结果表明本文的方法具有更好的收敛速度和精度,对缺陷的识别效果更好。In order to improve the quality of the inversion in the elastic wave CT, at the same time, taking into account the pathological characteristics of the coefficient matrix and low quality of the reconstruction image obtained by the 13PT-SIRT algorithm, a method based on principal component weighting preprocessing and weighted BPT-SIRT algorithm is proposed. The initial iterativc value obtained by the method of BPT is weighted,then, adding a weight to the principal component of the coefficient matrix, the element of ray matrix is weighted by the nonlinear exponential weighting function. The method is verified by numerical simulation and concrete filled steel tube specimens with defects. The results show that the method has better convergence speed and accuracy, and the recognition effect is better.

关 键 词：病态性 主元加权 预处理 反演成像 

分 类 号：O241.6[理学—计算数学]