基于预测控制理论的水产品价格模型

讨论了一种水产品价格非均衡蛛网模型，应用预测控制理论，使系统稳定运行，保证水产品供求差平稳跟踪预先给定的目标。定义了供求变化模式，研究了该模式中参数的选择对系统动态特性和鲁棒性的影响。运用Matlab软件进行仿真，得出该模型的响应曲线，结果表明，在商品上市前期，由于对市场信息了解不足等多种因素影响，在短时间内价格波动比较大，随着时间增长，市场逐步达到供需平衡，相邻两期价格的波动大体一致；模型参数＆增大可以减少超调，使系统稳定度增高，但动态响应越缓慢，供求差准确跟踪给定目标的时间越长。因此决策层可通过选择不同的参数制定不同的供求变化模式满足实际的需要，保证市场的稳定发展。仿真结果验证了该算法的优异性能。

The Price Model of Aquatic Products Based on Predictive Control Theory

This paper discusses a disequilibrium cobweb model of price of aquatic products,and applies predictive control theory,so that the system operates stably,and the deviation between supply and demand of aquatic products smoothly tracks the pre-given target.It defines the supply and demand change model,and researches the impact of parameter selection in this model on dynamic state and robustness of the system.I conduct simulation by Matlab software,to get the response curve of this model.The results show that in the early period of commodities coming into the market,affected by lack of market information and many other factors,the price fluctuates greatly in a short time.The market will gradually achieve balance between supply and demand over time,and the price fluctuations in the neighbouring two periods are broadly consistent.The increase in model parametercan decrease overshoot,to promote the stability of system,but the slower the dynamic response,the longer the deviation between supply and demand to accurately track a given target.Therefore,by selecting different parameters,the decision-makers can establish different models of supply and demand changes to meet the actual needs,and ensure stable development of market.Simulation results verify the excellent performance of this algorithm.