【作者】 丁永维；

【导师】 董峰；

【作者基本信息】 天津大学 ， 检测技术与自动化装置， 2007， 硕士

【摘要】 电阻层析成像(Electrical Resistance Tomography,简称ERT)技术是上个世纪80年代发展起来的一种高新检测技术,具有非侵入、响应速度快、成本低、安全性能好和可视化等优点,可实现对封闭管道或者过程容器设备内的多相流组分物质参数的可视化测量,具有广阔的应用前景。图像重建过程是最终实现ERT技术可视化的过程,图像重建的速度和精度是ERT图像重建过程中的两个关键因素。本文从ERT技术的原理出发,对ERT技术的图像重建算法进行了认真的研究,提出了改进方案,并设计了ERT仿真软件包。在本论文的研究中,作者主要完成了以下工作:1.对于ERT技术的正问题,用有限元方法对其进行求解,提出了数据存储和场域剖分的优化办法,实现了对场域的剖分,并在剖分的基础上,对正问题进行求解。2.对于ERT技术的逆问题,即图像重建,从两个方面进行了研究:非迭代图像重建算法和迭代图像重建算法。并分别提出了相应的图像重建算法:在非迭代图像重建算法中,提出了正则化图像重建算法,并提出了修正的正则化图像重建算法;在迭代图像重建算法中,提出了组合型图像重建算法。3.提出了新的图像重建评价标准,即图像相对误差,对图像重建效果进行评价。4.用C ++ Builder软件开发系统结合OpenGL开发工具,设计了ERT应用软件系统。该软件系统可以根据不同参数的设置情况,对正问题和逆问题进行分析。即通过设置不同的参数,对不同情况下的场域进行剖分,并对边界测量电压进行求解;通过选择不同的图像重建算法,实现图像重建;并对数据进行存储与显示。更多还原

【Abstract】 Electrical Resistance Tomography (ERT) technique is a high-new detection technique that has been developed from the eighties last century, it can be applied to measure the material parameters of multi-phase flow in a closed pipe or a process device, and it has a good foreground.Image reconstruction is the last step to realize visualization for ERT technique, and the reconstruction speed and the quality of the reconstructed images are two key factors. This paper is based on the principle of ERT technique, and carefully research has been made on image reconstruction algorithm, better reconstruction algorithms have been presented, and ERT simulation software kit has been designed.The main contribution and works are as follow:(1) For the forward problem of ERT, Finite Element Method is used to solve it. Data storage optimization method and field division optimization method are presented. The field is divided, and on the basic of the field division, the forward problem of ERT is solved.(2) For the inverse problem of ERT, that is, image reconstruction, research is done from two aspects: non-iterative image reconstruction algorithm and iterative image reconstruction algorithm. For non-iterative image reconstruction algorithm, regularization image reconstruction algorithm is revised and revised regularization image reconstruction algorithm is presented; for iterative image reconstruction algorithm, combined image reconstruction algorithm is presented.(3). A new evaluation standard for image reconstruction is presented, that is relative resistivity error to evaluate the image reconstruction effect.(4). An ERT application software system is developed with C++ Builder software development system and OpenGL development tool. The software system can solve the forward problem and the inverse problem according to different given parameter. With different given parameters, the field can be divide differently, and the marginal voltage can be calculated; with different image reconstruction algorithms, the image can be reconstruction differently; and the data can be stored and displayed.更多还原