Hopf Bifurcation Analysis of a New SEIRS Epidemic Model with Nonlinear Incidence Rate and Nonpermanent Immunity

Figure 1

The critical value, , as a function of the parameters: (a) for (magenta) and (green), (b) for (magenta), (blue), and (green), and (c) for and (magenta), (blue), (green), and (red).

(a)

(b)

(c)