论文部分内容阅读
本文根据现代控制理论中“黑箱”理论的思想,提出了一种直接采用土壤水瞬态运动模拟方法求得吸水项的方法,从而省去了试图估计根系分布的困难。并且在估计方法中采用线性系统的叠加原理,对SPAC系统进行分解与叠加,将异常复杂的SPAC系统的求解过程简化为对几个相对简单得多的子系统的求解,从而使得相应的求解与验证实验更加简单和方便。给出了采用交替方向的P—R有限差分二维模拟算法的计算表达式。并在估计桃树吸水模型中得到应用。提出了修正的桃(果)树吸水模型(函数)及其参数估计方法。对方法及模型的正确性进行了验证。
Based on the idea of “black box” in modern control theory, this paper presents a method to obtain the water absorption term by directly using the soil water transient motion simulation method, thus eliminating the difficulty of trying to estimate the root distribution. And in the estimation method, the superposition principle of linear system is adopted to decompose and superpose the SPAC system. The solution to the complex SPAC system is simplified to solve a few relatively simple subsystems, so that the corresponding solution Validation experiments easier and more convenient. The computational expression of P-R finite difference two-dimensional simulation algorithm with alternate direction is given. It is also used in the estimation of peach water absorption model. A modified model (function) of peach (fruit) tree water absorption and its parameter estimation method are proposed. The correctness of the method and the model was verified.