[1] Jenkins D R.Interpretation of shadowgraph patterns in Rayleigh-Benard convection[J].J Fluid Mech,1988,190:451-469. [2] Stuart J T.On the cellular patterns in thermal convection[J].J Fluid Mech,1964,18:481-498. [3] LI Ji-bin,ZHAO Xiao-hua,LIU Zheng-rong.Theory and Application of Generalized Hamiltonian Systems[M].Beijing:Science Press,1994.(in Chinese) [4] LI Ji-bin,Christie J R,Gopalsamy K.Perturbed generalized Hamiltonian systems and some advection models[J].Bull Austral Math Soc,1998,57:1-24. [5] Palm E.On the tendency towards hexagonal cells in steady convection[J].J Fluid Mech,1960,8:183-192. [6] Zaslavsky G M,Sageer R Z,Vsikov D A,et al.Weak Chaos and Qu asi-Regular Patterns[M].Cambridge:Cambridge University Press,1991. [7] Stuart J T.The Lagrangian picture of fluid motion and its implication for flow structures[J].IMA J Appl Math,1991,46:147-163.