基于SEM图像的细颗粒泥沙絮体3维分形研究及其应用

具有分形特征是细颗粒泥沙絮体的重要特性，为了解决目前主要是通过絮体SEM图像研究其2维分形特性的问题，利用SEM图像灰度值重建细颗粒泥沙絮体3维图像，通过MATLAB编程用盒计数法计算絮体3维分形维数；然后基于絮体3维分形维数，推导出细颗粒泥沙静水沉降时清浑交界面的沉降公式，并将其应用在滇池底泥清混交界面的沉降计算中，其计算误差在5%以内。结果表明，直接利用絮体SEM图像计算絮体3维分形维数是可行的，避免了图像处理中人为误差的引入，且通过其推导的沉降公式可用于计算清混交界面的沉速。

3-D Fractal Study of Fine Sediment Floc Using SEM Image and Its Application

An important characteristic of floc formed by fine sediment is its fractal feature,but many researches have been focused on 2-D fractal properties through analyzing SEM image of floc.In order to solve this problem,3-D image of flocs was reconstructed under gray values,and 3-D fractal dimension of flocs was calculated using box-counting method with the help of MATLAB programming.Moreover,a settling formula of interface was derived based on 3-D fractal dimension of flocs and used in the settling calculation of interface of silt in Dianchi Lake,with the calculation error of 5%.The results showed that it is practicable to use grey-scale image to obtain 3-D fractal dimension of flocs,which can avoid man-made error in the image processing,and the formula deduced from 3-D fractal dimension is available to calculate the settling velocity of the interface.