Perturbation to Mei Symmetry and Generalized Mei Adiabatic Invariants for Birkhoffian Systems
This paper investigates the perturbation to Mei symmetry for Birkhoffian systems. The criterion equation of the perturbation
to Mei symmetry is established. The condition for existence of generalized Mei adiabatic invariant induced directly from the
perturbation to Mei symmetry is obtained, and its form is presented. Finally, an example is discussed to further illustrate
the application of the results.