Fixed-Time Synergetic Control Based on SEAIQR Model for COVID-19 Epidemic

The COVID-19 epidemic has a profoundly negative impact on the lives of people all over the world. The measure of quarantine is one of the prominent means to suppress the spread of COVID-19. Therefore, we consider a novel susceptible-exposed-asymptomatic infected-symptomatic infected-quarantine-recovered (SEAIQR) model by adding quarantine subgroup to the SEAIR infectious disease model. Furthermore, to control the spread of the infectious disease, we design a fixed-time synergetic control (FTSC) approach based on the new model to develop three control strategies, which include quarantine of asymptomatic and symptomatic infected subgroups and vaccination of susceptible subgroup. In particular, the synergetic control method can provide non-chattering characteristics for the control system. In addition, the convergence speed of tracking reference signals can be improved with FTSC. Besides, the FTSC method can enable the latent subgroup, the asymptomatic infected subgroup and the symptomatic infection subgroup to converge to the desired value within a settling time without knowing the initial numbers of infection. Finally, numerical simulations are conducted to verify that the infectious disease can be controlled within a finite time with two groups of initial infection values.