Qualitative analysis for a mathematical model of aids

In this paper a mathematical model of AIDS is investigated. The conditions of the existence of equilibria and local stability of equilibria are given. The existences of transcritical bifurcation and Hopf bifurcation are also considered, in particular, the conditions for the existence of Hopf bifurcation can be given in terms of the coefficients of the characteristic equation. The method extends the application of the Hopf bifurcation theorem to higher differential equations which occur in biological models, chemical models, and epidemiological models etc.This project is supported by the National Science Foundation Tian Yuan Terms and LNM Institute of Mechanics Academy of Science.This project is supported by the National and Yunnan Province Natural Science Foundation of China.