基于Sigmoid函数的ECT灵敏度预处理

ECT sensitivity preprocessing based on Sigmoid function

摘要:

电容层析成像(ECT)图像重建算法利用敏感度矩阵作为先验知识，反演管道内介质的分布情况，因此，灵敏度矩阵对图像重建的质量起着至关重要的作用。由于ECT传感器具有软场特性，场域内的灵敏度分布并不均匀，传感器中心区域与边缘区域差异过大，影响重建图像质量。本文提出一种基于Sigmoid函数的灵敏度预处理方法，由仿真实验结果可知，该方法能显著提高灵敏度矩阵的均匀性，并大大提高重建图像的质量：图像空间误差(ISE)降低0.382 5；图像相对误差(RE)降低0.386 5；相关系数(CC)提升0.060 8，验证了此方法在ECT图像重建中的可行性。

Abstract:

Electrical Capacitance Tomography(ECT) image reconstruction algorithms utilize the sensitivity matrix as prior knowledge to invert the distribution of media within the pipeline, hence, the sensitivity matrix plays a crucial role in the quality of image reconstruction. Due to the soft-field characteristics of ECT sensors, the sensitivity distribution within the field is not uniform, with significant differences between the central and peripheral areas of the sensor, affecting the quality of the reconstructed images. This paper proposes a sensitivity preprocessing method based on the Sigmoid function. Simulation experimental results show that this method can significantly improve the uniformity of the sensitivity matrix and greatly enhance the quality of the reconstructed images: the Image Spatial Error(ISE) is reduced by 0.3825; the Relative Error(RE) is reduced by 0.386 5; and the Correlation Coefficient(CC) is increased by 0.0608, validating the feasibility of this method in ECT image reconstruction.