In this paper, the authors consider limit cycle bifurcations for a kind of nonsmooth polynomial differential systems by perturbing a piecewise linear Hamiltonian system with a center at the origin and a heteroclinic l...In this paper, the authors consider limit cycle bifurcations for a kind of nonsmooth polynomial differential systems by perturbing a piecewise linear Hamiltonian system with a center at the origin and a heteroclinic loop around the origin. When the degree of perturbing polynomial terms is n(n ≥ 1), it is obtained that n limit cycles can appear near the origin and the heteroclinic loop respectively by using the first Melnikov function of piecewise near-Hamiltonian systems, and that there are at most n + [(n+1)/2] limit cycles bifurcating from the periodic annulus between the center and the heteroclinic loop up to the first order in ε. Especially, for n = 1, 2, 3 and 4, a precise result on the maximal number of zeros of the first Melnikov function is derived.展开更多
将无扰闭轨道变量变换到作用-角变量,再将微扰变量在无扰闭轨道附近展开,获得了有微扰的作用-角变量一级近似表达式。以无扰闭轨道的周期为采样时间,用作用-角变量表达式建立了二维多频驱动的Poincar'e映射,由其中的作用变量映射定...将无扰闭轨道变量变换到作用-角变量,再将微扰变量在无扰闭轨道附近展开,获得了有微扰的作用-角变量一级近似表达式。以无扰闭轨道的周期为采样时间,用作用-角变量表达式建立了二维多频驱动的Poincar'e映射,由其中的作用变量映射定义了多频驱动的次谐Melnikov函数,并用该函数,给出了Hopf分岔条件。并应用到多频驱动的Duffing-Van der pol系统中,导出了该系统的Hopf分岔条件。按分岔条件取参数,对三频驱动的Duffing-Van der pol方程进行了数值模拟,无一例外地均出现了Hopf分岔。展开更多
基金supported by the National Natural Science Foundation of China(No.11271261)the Natural Science Foundation of Anhui Province(No.1308085MA08)the Doctoral Program Foundation(2012)of Anhui Normal University
文摘In this paper, the authors consider limit cycle bifurcations for a kind of nonsmooth polynomial differential systems by perturbing a piecewise linear Hamiltonian system with a center at the origin and a heteroclinic loop around the origin. When the degree of perturbing polynomial terms is n(n ≥ 1), it is obtained that n limit cycles can appear near the origin and the heteroclinic loop respectively by using the first Melnikov function of piecewise near-Hamiltonian systems, and that there are at most n + [(n+1)/2] limit cycles bifurcating from the periodic annulus between the center and the heteroclinic loop up to the first order in ε. Especially, for n = 1, 2, 3 and 4, a precise result on the maximal number of zeros of the first Melnikov function is derived.
基金the Natural Science Foundation of Anhui Province(1308085MA08)the Doctor Program Foundation(2012)of Anhui Normal University+1 种基金the NNSF of China(11271197)the key NSF of Education Ministry of China(207047)
文摘将无扰闭轨道变量变换到作用-角变量,再将微扰变量在无扰闭轨道附近展开,获得了有微扰的作用-角变量一级近似表达式。以无扰闭轨道的周期为采样时间,用作用-角变量表达式建立了二维多频驱动的Poincar'e映射,由其中的作用变量映射定义了多频驱动的次谐Melnikov函数,并用该函数,给出了Hopf分岔条件。并应用到多频驱动的Duffing-Van der pol系统中,导出了该系统的Hopf分岔条件。按分岔条件取参数,对三频驱动的Duffing-Van der pol方程进行了数值模拟,无一例外地均出现了Hopf分岔。