Computation of the Domain of Attraction for Suboptimal Immunity Epidemic Models Using the Maximal Lyapunov Function Method

Figure 3

(a) the DOA when (𝐴,𝛽,𝑣,𝑐,𝑎,𝜇,𝑘)=(6,0.5,1.27,2,4,1,0.5) for the model (20), (b) a detailed look for the phase portrait in (a).

(a)

(b)