地点：腾讯会议  398 905 279

报告人：刘期怀（桂林电子科技大学，教授）

题目:  Stability of motion induced by a point vortex under arbitrary polynomial perturbations

摘要:  In this talk, we shall prove the stability of the particle advection around a fixed vortex in a two dimensional ideal fluid under the action of a periodic background flow induced by a polynomial field. The proof relies on the identification of closed invariant curves around the origin by means of Moser’s invariant curve theorem.

时间：12月3日（周四）10:00-11:00

地点：腾讯会议  398 905 279

报告人：刘期怀（桂林电子科技大学，教授）

题目:  Generalized Hamiltonian forms of dissipative mechanical systems via a unified approach

摘要:  In this paper, we presents a unified method upon Hamiltonian description of one dimensional second order dissipative systems. In this method, the first order partial differential

equation is constructed by the first integral. As long as the corresponding characteristic

equation has an explicit solution, the dissipative system has an explicit Hamiltonian

function. The Hamiltonians for three types of representative dissipative systems have

been established and some interesting examples are given from the perspective of

Hamiltonian dynamics.

时间：12月3日（周四）11:00-12:00

地点：腾讯会议  398 905 279

报告人：刘期怀（桂林电子科技大学，教授）

题目:  Invariant set of contact Hamiltonian system

摘要:  In this talk, we investigate the orbits dynamics of a special invariant set (the zero energy level domain) of autonomous contact Hamiltonian system. We found that, under general conditions, the energy levels of the orbits starting from different energy

level domains tend to zero. In a sense, the zero energy level domain is a domain of attraction. In some cases, such a domain of attraction has none of nontrivial periodic orbits. A few interesting

examples are presented.