BIFURCATION AND STABILITY ANALYSIS FOR LIQUID SURFACES

A more comprehensive discussion on the bifurcation problems for the shape of liquidsurfaces is made in this paper.The necessary conditions for bifurcation are given,and thebifurcating solutions near bifurcation points can be obtained by perturbation technique.Finally the stability of the bifurcating states is analyzed by means of the principle ofminimum potential energy.     

实验性神经起步点自发放电的整数倍节律和随机自共振

本文介绍了实验中发现的无外界周期刺激的神经起步点放电节律随[Ca＋＋]。变化产生的整数倍节律，并用描写神经放电的理论模型（Chay模型）进行数值模拟。结果发现：在相应的参数区间，确定性模型为－Hopf分岔，无整数倍节律；在随机模型中，在Hopf分岔点附近，整数倍节律产生，该整数倍节律是通过随机自共振产生的。实验中与模型的整数倍节律处于桢的参数区间，位于周期1和阈下振荡之间：并且有相同的特征；其峰峰间期处于一个基本峰峰新时期的整数倍，峰峰间期出现频率随峰峰新时期增加呈现出指数降低。这提示，实验中的整数倍节律是通过随机自共振产生的。     

Spatial coherence resonance induced by coloured noise and parameter diversity in a neuronal network

Spatial coherence resonance in a two-dimensional neuronal network induced by additive Gaussian coloured noise and parameter diversity is studied. We focus on the ability of additive Gaussian coloured noise and parameter diversity to extract a particular spatial frequency (wave number) of excitatory waves in the excitable medium of this network. We show that there exists an intermediate noise level of the coloured noise and a particular value of diversity, where a characteristic spatial frequency of the system comes forth. Hereby, it is verified that spatial coherence resonance occurs in the studied model. Furthermore, we show that the optimal noise intensity for spatial coherence resonance decays exponentially with respect to the noise correlation time. Some explanations of the observed nonlinear phenomena are also presented.     

简化Hodgkin-Huxley反应-扩散方程描述的可激活介质中的旋转波

对一个由简化Hodgkin-Huxley反应 扩散方程描述的可激活介质的运动进行数值计算，在一定的初始条件和边界条件下，获得了稳定的旋转波解．根据可激活介质的特点，把模型近似为一些比较简单的形式，从这些近似形式出发，对旋转波产生的原因在理论上进行了定性分析 关键词：     

Taming desynchronized bursting with delays in the Macaque cortical network

Inhibitory coupled bursting Hindmarsh-Rose neurons are considered as constitutive units of the Macaque cortical network. In the absence of information transmission delay the bursting activity is desynchronized,giving rise to spatiotemporally disordered dynamics. This paper shows that the introduction of finite delays can lead to the synchronization of bursting and thus to the emergence of coherent propagating fronts of excitation in the space-time domain. Moreover,it shows that the type of synchronous bursting is uniquely determined by the delay length,with the transitions from one type to the other occurring in a step-like manner depending on the delay. Interestingly,as the delay is tuned close to the transition points,the synchronization deteriorates,which implies the coexistence of different bursting attractors. These phenomena can be observed by different but fixed coupling strengths,thus indicating a new role for information transmission delays in realistic neuronal networks.     

抽运参数随时间慢变所诱发Laser-Lorenz方程的分岔与光学双稳态

提出了新的简便的方法研究具有入射信号的半经典Laser-Lorenz方程-由于抽运参数随时间慢变,导致分岔滞后,并诱发暂态的光学双稳态-通过量级平衡和用线性化系统的慢变解作近似,给出了分岔转迁的量级关系和暂态光学双稳态发生的条件,并通过数值计算给出分岔转迁区间和暂态光学双稳态的滞后环- 关键词：     

ADAPTIVE INTERVAL WAVELET PRECISE INTEGRATION METHOD FOR PARTIAL DIFFERENTIAL EQUATIONS

IntroductionThepreciseintegrationmethod(PIM) [1],whichwasproposedforsolvingstructuraldynamicequations.Thismethodissimplerandpossesseshigherprecision .Forlinearsteadystructuraldynamicsystems,itsnumericalresultsattheintegrationpointsarealmostequaltothatoftheexactsolutioninmachineaccuracy .InthepreciseintegrationmethodforsolvingPDEs,theequationsshouldbediscretizedinthephysicalspaceforobtainingthesystemofODEsintime ,whichisoftenexecutedbythefinitedifferencemethodorthefiniteelementmethod .Inrec…     

Strongly resonant bifurcations of nonlinearly coupled van der Pol-Duffing Oscillator

IntroductionThecomplicateddynamicalbehaviorofnonlinearoscillatorsystemsisafrontiertopicinthestudyofnonlineardynamicsatthepresent,whichplaysanimportantroleinrealityandareconnectedcloselywithmanydynamicalproblemsinengineering.Generallyspeaking,therearenogeneralmethodstofindouttheprecisesolutionsofnonlineardifferentialequahonswhichdescribenonlinearoscillatorsystems.Since1920s,scholarshavebeensearchingforcommonlyaPPlicableasymptoticalmethods,andtherehavebeensomespeCialbooks,suchas[1~4]etc..Howev…     

一类油膜转子刚性碰摩模型的动力学研究

本文结合非线油膜力模型和冲量定理，建立了Ｊｅｆｆｃｏｔｔ转子碰摩的刚性约束模型，通过对模型的数值模拟，揭示了转子系统碰摩产生的途径的过程，并 混沌运动发生的条件及其与碰摩的关系。     

时变参数系统的非线性动力学研究

本地具有时变参数的非线性系统的摄动方法、分岔与混沌以及安全盆等问题进行综述，并简要介绍一些近期结果。