知识约简是粗糙集研究的内容之一,粒度计算问题结合粗糙集的理论和应用可以解决一些问题.在一个由信息系统构成的多粒度数据集上,利用提出的Seeking Common Ground While Eliminating Differences(SCED)模型和给出的算法,较好地解决了一些多粒度下的属性约简,所给出的实例从时间复杂度上也充分说明了模型和算法的有效性.
In this paper, we propose a susceptible-infected-susceptible （SIS） model on complex networks, small-world （WS） networks and scale-free （SF） networks, to study the epidemic spreading behavior with time delay which is added into the infected phase. Considering the uniform delay, the basic reproduction number R0 on WS networks and ~ on SF networks are obtained respectively. On WS networks, if R0 〈 1, there is a disease-free equilibrium and it is locally asymptotically stable; if R0 〉 1, there is an epidemic equilibrium and it is locally asymptotically stable. On SF networks, if R0 〈_4 1, there is a disease-free equilibrium; if -R0 〉 1, there is an epidemic equilibrium. Finally, we carry out simulations to verify the conclusions and analyze the effect of the time delay T, the effective rate A, average connectivity 〈k） and the minimum connectivity m on the epidemic spreading.
