Nonlinear Analysis And Control To A Class Of The Biological Model

Biomathematical model is one kind of important methods of studying ecology.The predator-prey ecosystems are more and more complex.At present,the most papers are focused on stability,periodic solution and Hopf bifurcation.First,this paper discusses the periodicity,the gradually stability, Hopf bifurcation and chaos phenomena of the biomathematical model of multi-population red tides,which are based on the ecological factor of red tide.It is proved that there exist chaos behaviors by calculating the Lyapunov exponent.This paper adds the harvesting terms to biomathematical model as disturbance,and studies the impulsive control of this new system.This ecological system with uncertain disturbance is controlled to an equilibrium point.The sufficient conditions of robust stabilization of the system are obtained.The conclusion is significant in practice to forecast and control the red tide.Next,for a kind of spruce aphides and their predator international model,an adaptive fuzzy controller with biological characteristic is introduced in this paper.The parameter adaptive law is formed,we adjust the parameters to make sure the density of spruce aphides and their predator track the ideal trajectory,the stability of the system is guaranteed. At last,the computer simulation demonstrates the effectiveness of this kind of controller.This provides academic basis for the persistence and balance of the ecological system.In order to carries out vermin general management on natural enemy- vermin model,the natural enemy- vermin model is exerted controlling such as harvesting,putting into circulation.It is important to taking precautions against and curing pasties,protecting environment and realizing the sustainable development of ecosystem.