3/2-global attractivity of the zero solution of the

We obtain 3/2-condition for global attractivity to occur in the“food-limited” type functional differential equation x′(t)+[1+x(t)] [1-cx(t)]F(t,x(·))=0. These results contain and improve all corresponding t heorems in literature.     

Stability and Neimark-Sacker bifurcation analysis of a food-limited population model with a time delay

In this paper,a kind of discrete delay food-limited model obtained by the Euler method is investigated,where the discrete delay τ is regarded as a parameter.By analyzing the associated characteristic equation,the linear stability of this model is studied.It is shown that Neimark-Sacker bifurcation occurs when τ crosses certain critical values.The explicit formulae which determine the stability,direction,and other properties of bifurcating periodic solution are derived by means of the theory of center manifold and normal form.Finally,numerical simulations are performed to verify the analytical results.     

食物有限的时滞种群模型的振动性

将考虑两类具有变时滞非线性有限食物种群模型N′(t)=r(t)N(t)K-N(p(t))/K+s(t)N(σ(t)),t≥ 0和N′(t)=r(t)N(t)K-Nα(p(t))/K+s(t)Nα(σ(t)),t≥ 0,的振动性,其中α>0,ρ(t)≤t,σ(t)≤t.我们的工作推广并改进了相关文献的结果.     

Stability and Neimark-Sacker bifurcation analysis of food-limited population model with time delay

In this paper, a kind of discrete delay food-limited model obtained by Euler method is investigated, where the discrete delay τ is regarded as a parameter. By analyzing the associated characteristic equation, the linear stability of this model is studied. It is shown that Neimark-Sacker bifurcation occurs when τ crosses some critical values. The explicit formulae which determine the stability, direction, and other properties of bifurcating periodic solution are derived by means of the theory of center manifold and normal form. Finally, numerical simulations are performed to verify the analytical results.