考虑了一类带Beddington-DeAngelis反应项的捕食-食饵模型正解的存在性和惟一性.首先利用分歧理论给出正解存在的充分条件,并刻画了整体分歧的结构.然后利用特征值变分原理将所给的条件简化,从而得到正解存在的更为简单更好计算的充分条件和必要条件.最后利用隐函数定理和广义极大值原理在一维情况下给出了正解的存在惟一性.
The predator-prey model with Beddington-DeAngelis functional response is considered. A necessary and sufficient condition for the existence of positive solutions is obtained. Moreover,a range of parameters for the uniqueness of positive solution is described in one dimension. The method used here is based on the global bifurcation theory,the implicit function theorem and the generalized maximum principle.