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

Figure 5

Stable cycle generated by supercritical Hopf bifurcation in , planes and in , respectively, for (), determined by a custom orthogonal collocation on finite elements algorithm. Unstable endemic equilibrium (red marker): . Period: days. ode113: Adams-Bashforth-Moulton PECE solver of orders 1 to 12 (Matlab).

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