Of the various control measures available, lockdown is widely considered to be the most reliable method for containing the spread of Coronavirus. This study presents two mathematical models utilizing $\alpha$-fractional derivatives to investigate the significance of lockdown in reducing the spread of the virus. In this article, the entire population is divided into four groups: \begin{enumerate} \item The first group comprises the susceptible population who are not under lockdown. \item The second group consists of susceptible individuals who are under lockdown. \item The third group comprises infected individuals who are not under lockdown. \item The fourth group consists of infective individuals who are under lockdown. \end{enumerate} One of the aforementioned methods examines the dynamics of COVID-19 by generalizing the SEIR model using $\alpha$-fractional derivatives. The second model comprises five nonlinear differential equations of $\boldsymbol{\alpha}$-fractional order. In both methods, $ \boldsymbol{\alpha} = (\alpha_1,\cdots,\alpha_n) $, where $ 0 < \alpha_i \leq 1 $ for all $ 1 \leq i \leq n$. In other words, if $ \mathbb{T} = (0,1]$, then $ \boldsymbol{\alpha} \in \mathbb{T}^n$.
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Dehghan Nezhad, A. and Moslemi Ghadikolaei, A. (2025). Analysis of quarantine and liberate effects on viral infection using SEIR and Caputo $ \alpha $-fractional-order model. Computational Methods for Differential Equations, 13(3), 768-782. doi: 10.22034/cmde.2024.60950.2607
MLA
Dehghan Nezhad, A. , and Moslemi Ghadikolaei, A. . "Analysis of quarantine and liberate effects on viral infection using SEIR and Caputo $ \alpha $-fractional-order model", Computational Methods for Differential Equations, 13, 3, 2025, 768-782. doi: 10.22034/cmde.2024.60950.2607
HARVARD
Dehghan Nezhad, A., Moslemi Ghadikolaei, A. (2025). 'Analysis of quarantine and liberate effects on viral infection using SEIR and Caputo $ \alpha $-fractional-order model', Computational Methods for Differential Equations, 13(3), pp. 768-782. doi: 10.22034/cmde.2024.60950.2607
CHICAGO
A. Dehghan Nezhad and A. Moslemi Ghadikolaei, "Analysis of quarantine and liberate effects on viral infection using SEIR and Caputo $ \alpha $-fractional-order model," Computational Methods for Differential Equations, 13 3 (2025): 768-782, doi: 10.22034/cmde.2024.60950.2607
VANCOUVER
Dehghan Nezhad, A., Moslemi Ghadikolaei, A. Analysis of quarantine and liberate effects on viral infection using SEIR and Caputo $ \alpha $-fractional-order model. Computational Methods for Differential Equations, 2025; 13(3): 768-782. doi: 10.22034/cmde.2024.60950.2607
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