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Effects of aging and links removal on epidemic dynamics in scale-free networks

K. P. Chan·Dafang Zheng·P. M. Hui
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Abstract

We study the combined effects of aging and links removal on epidemic dynamics in the Barabási-Albert scale-free networks. The epidemic is described by a susceptible-infected-refractory (SIR) model. The aging effect of a node introduced at time $t_{i}$ is described by an aging factor of the form $(t-t_{i})^{-β}$ in the probability of being connected to newly added nodes in a growing network under the preferential attachment scheme based on popularity of the existing nodes. SIR dynamics is studied in networks with a fraction $1-p$ of the links removed. Extensive numerical simulations reveal that there exists a threshold $p_{c}$ such that for $p \geq p_{c}$, epidemic breaks out in the network. For $p < p_{c}$, only a local spread results. The dependence of $p_{c}$ on $β$ is studied in detail. The function $p_{c}(β)$ separates the space formed by $β$ and $p$ into regions corresponding to local and global spreads, respectively.

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K. P. Chan, Dafang Zheng, P. M. Hui. 2004-02-05. Effects of aging and links removal on epidemic dynamics in scale-free networks. https://doi.org/10.1142/s0217979204025622

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