Global dynamics of a fractional-order COVID-19 model with modified Crowley–Martin incidence rate and optimal vaccination control using real data analysis
摘要
This work presents a data-driven fractional-order SEIR model that incorporates a modified Crowley–Martin incidence function to capture nonlinear saturation and behavioral effects in the transmission of COVID-19. By employing the Caputo derivative, the model accounts for memory-dependent infection and recovery processes that cannot be represented in classical integer-order formulations. Fundamental analytical properties of the system, including positivity, boundedness, and the existence and uniqueness of solutions, are rigorously established. The basic reproduction number