北京赛车PK10正规平台

Limit cycle bifurcations near a double homoclinic loop with a nilpotent saddle of order m

Limit cycle bifurcations near a double homoclinic loop with a nilpotent saddle of order m

发布者:文明办发布时间:2019-06-24浏览次数:333


主讲人:杨俊敏 河北师范大学教授


时间:2019年7月9日9:00


地点:徐汇校区3号楼332报告厅


举办单位:数理学院


内容介绍:In this paper, we study the explicit expansion of the first order Melnikov  function near a double homo-clinic loop passing through a nilpotent saddle of  order min a near-Hamiltonian system. For any positive integer m(m ≥1), we derive  the formulas of the coefficients in the expansion, which can be used to study  the limit cycle bifurcations for near-Hamiltonian systems. In particular, for m  =2, we use the coefficients to consider the limit cycle bifurcations of general  near-Hamiltonian systems and give the existence conditions for 10, 11, 13, 15  and 16 (11, 13 and 16, respectively) limit cycles in the case that the  homoclinic loop is of cuspidal type (smooth type, respectively) and their  distributions. As an application, we consider a near-Hamiltonian system with a  nilpotent saddle of order 2and obtain the lower bounds of the maximal number of  limit cycles.