the domain of attraction for the endemic equilibrium of an sirs epidemic model

in this paper, a new method is adopted to construct a lyapunov function for the endemic equilibrium of the j. mena-lorca and h.w. hothcote’s sirs epidemic model with bilinear incidence and constant recruitment. on the basis of the lyapunov function, the domain of the attraction of the endemic equilibrium is estimated by solving an lmi optimization problem with multivariate polynomial objective function and constraints.