應(yīng)yl7703永利官網(wǎng)李萬同教授與王智誠教授邀請，杭州師范大學(xué)徐衍聰教授將于2022年6月24日-6月26日與我校有關(guān)師生進(jìn)行在線學(xué)術(shù)研討，其中6月25日舉行線上專題學(xué)術(shù)報告。

報告題目:Global Bifurcation analysis of an SIRS disease model with a convex incidence rate

時 間：6月25日下午14:40

騰訊會議ID：790 1862 7942 入會密碼：123456

摘 要：In this paper, the global dynamics of an susceptible infectious recovered (SIRS) epidemic model with a generalized non-linear incidence function are investigated. It is shown that (1) not the basic reproduction number, but a sub-threshold value acts as a threshold value for the disease spread; (2) as parameters vary, the model exhibits saddle-node bifurcation, forward bifurcation, backward bifurcation, cusp type degenerate Bogdanov-Takens bifurcation of codimension 2 and 3, Hopf bifurcation, generalized Hopf bifurcation, homoclinic bifurcation, degenerate homoclinic bifurcation. Particularly, we find the existence of isolas of limit cycles, which tells us that two stable limit cycles and one unstable limit cycles coexist. We derive that the existence of codimension-three Bogdanov-Takens bifurcation as the organizing center of complex dynamics yields the bifurcation of homoclinic cycle and isola bifurcation of limit cycles, which provide the possible existence of three limit cycles. Actually, two limit cycles can emanate simultaneously from the isola center. Numerical simulations are presented to illustrate the theoretical results.

徐衍聰教授簡介

徐衍聰，杭州師范大學(xué)數(shù)學(xué)系教授，博士生導(dǎo)師，系主任，美國（SIAM）工業(yè)與應(yīng)用數(shù)學(xué)會員，美國數(shù)學(xué)評論評論員。目前主要從事動力系統(tǒng)分支理論、局部斑圖分支及應(yīng)用研究，主持國家自然科學(xué)基金面上項目各類基金10余項。

甘肅應(yīng)用數(shù)學(xué)中心

甘肅省高校應(yīng)用數(shù)學(xué)與復(fù)雜系統(tǒng)省級重點(diǎn)實(shí)驗(yàn)室

yl7703永利官網(wǎng)

萃英學(xué)院

2022年6月22日