一类具有非线性死亡率的时滞Nicholson飞蝇方程的持久性

Permanence for a Delayed Nicholson's Blowflies Model with a Nonlinear Density-dependent Mortality Term

研究了一类具有非线性死亡率的广义时滞Nicholson飞蝇方程.在容许初值的条件下,利用解的延拓定理,首先证明了该方程的所有解是正的并且是整体存在的,然后利用微分不等式的技巧,证明了该方程所有解具有正的上下确界,获得了该方程所有解具有持久性的充分条件.由于所考虑的模型比同类文献中的模型更加广泛,从而改进和推广了已有文献中的相关结果,并给出了一个具体的例子.

In this paper,we study a generalized Nicholson＇s blowflies model with a nonlinear density-dependent mortality term.Under the admissible initial conditions,by using continuous dependence theorem,some criteria to guarantee the positivity and global existence of solutions are obtained.Then,by applying differential inequality techniques,we give the positive lower bound and upper bound of solutions,and get the permanence of this model.Moreover,we present an example to illustrate our main results.