用遗传算法优化估计Van Genuchten方程参数

描述土壤水分特征曲线的Van Genuchten方程是一个非线性复杂方程，采用传统的方法对方程参数进行估计往往因为计算复杂和人为因素的影响，而使估计结果带有较大的误差。遗传算法是当前处理一般非线性数学模型优化的一种新的优秀方法。为此，采用实数编码多子种群遗传算法对方程的参数进行优化估计。算例结果表明用遗传算法优化估计Van Genuchten方程参数具有求解速度快、计算精度和自动化程度高、人为干扰因素小、通用性强等优点。因此，遗传算法可作为计算Van Genuchten方程参数的一种新方法。

Using Genetic Algorithm to Estimate Parameters of Van Genuchten Equation

The Van Genuchten Equation （VGE） which is used to describe the feature of soil water movement is super-set and nonlinear. Using traditional method calculating the VGEs parameters often results with a high margin of error because of complication and artificial factors. Genetic Algorithms （GA） is a new outstanding evolutionary computation method for solving complex nonlinear model. Therefore, application of real coding that based Poly-Population Genetic Algorithm （PPGA） on the VGE＇s parameters optimization is proposed. The results show that PPGA is a high effective algorithm with many good properties such as fast computing speed, high efficiency, high precision, small artificial factors and so on. Consequently, PPGA is a new method for calculating Van Genuchten equation parameters.