研究了一类具有Logistic增长和HollingⅡ类功能反应的免疫模型.以时滞为分支参数,分析了系统正平衡点的稳定性和Hopf分支的存在性;然后利用中心流形定理和规范型方法,给出了分支周期解的分支方向与稳定性的计算公式,利用数值模拟验证了所得结论.
A basic model of immune with Logistic growth and Holling type-Ⅱfunctional response has been studied.By choosing the time delay as the parameter,the stability of the positive equilibrium and the existence of the Hopf bifurcation are investigated. By using the normal form theory and the center argument,the explicit formulae which determine the stability and the direction are derived.Finally,numerical simulations supporting our theoretical results are also included.