差异演化算法在Van Genuchten方程参数优化估计中的应用

Application of differential evolution in optimizing parameters of Van Genuchten equation

描述土壤水分特征曲线的Van Genuchten方程是一非线性方程,采用传统的方法对方程参数进行估计往往因为计算复杂而使估计结果带有较大的误差。差异演化算法是一种简单、有效的新智能进化算法,因此,文章用该算法对Van Genuchten方程的参数进行优化估计;结果表明,差异演化算法在Van Genuchten方程参数估计应用中,表现出求解速度快、计算精度和自动化程度高、通用性强等优点,可作为计算Van Genu-chten方程参数的一种新方法。

The Van Genuchten equation（VGE） of the curves used to describe the feature of soil water movement is super-set and nonlinear. The traditional method of calculating the VGE＇s parameters often results in a high margin of error because of complication. Differential evolution （DE） is a new outstanding evolutionary computation method for solving complex nonlinear models. In this paper, the solution program of differential evolution is compiled and used to estimate parameters of the VGE. The results show that DE is a highly effective algorithm with good properties such as high efficiency, high precision, fast computing speed, universality, etc. Consequently, DE can be used as a new method to calculate VGE＇s parameters.