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排序方式: 共有1110条查询结果,搜索用时 15 毫秒
31.
The article is concerned with mathematical models for media with oscillating inclusions. These models consist of mutually connected equations, one of which is the wave equation for carrying medium and others are equations of motion for partial oscillators. To close these models, we use cubic and nonlocal equations of state for the carrying medium. Travelling wave solutions to these models are studied in detail. Using qualitative analysis methods, the phase space is shown to contain periodic, homo- and heteroclinic trajectories. Moreover, in the case of nonlocal models we observe the creation of quasiperiodic and chaotic regimes. Bifurcations of localized regimes are studied via the Poincaré section technique. 相似文献
32.
Vando Narciso 《Mathematical Methods in the Applied Sciences》2015,38(4):775-784
This paper is concerned with the existence of a global attractor for the nonlinear viscoelastic beam equation with past history memory where g(ut) is a damping like | ut | rut and f(u) is a source term like | u | αu ? | u | βu, by considering 0 ≤ β < α and r > 0. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
33.
使用Galerkin方法,结合Sobolev空间理论和不等式技巧,给出了广义神经传播方程解的存在唯一性定理,然后利用吸引子存在性定理,采用半群方法证明了方程整体吸引子的存在性. 相似文献
34.
横向磁场激励下铁磁梁式板的混沌运动分析 总被引:9,自引:0,他引:9
在磁体力分布的磁弹性理论模型和磁场准静态假定模式基础上,对于处在周期时变磁场 中的不可移简支铁磁梁式板非线性磁弹性动力特性进行定性与定量分析.首先利用磁场的摄 动技术和结构变形的模态法,导出了关于模态坐标的非线性动力方程;然后利用Melnikov方 法,从理论上给出这一磁弹性动力系统可能出现混沌运动的必要条件及参数范围;最后采用变 步长Runge-Kutta数值积分方法对其磁弹性相互作用的混沌现象进行了定量搜索与模拟,并 利用其轨迹的Poincare截面图与Liapunov指数加以判断.结果表明磁弹性简支梁式板在横 向周期时变磁场中存在混沌吸引子,且在机械阻尼很小时其混沌吸引子表现出稠的特性. 相似文献
35.
The dissipative quantum Zakharov equations are mainly studied. The existence and uniqueness of the solutions for the dissipative quantum Zakharov equations are proved by the standard Galerkin approximation method on the basis of a priori estimate. Meanwhile, the asymptotic behavior of solutions and the global attractor which is constructed in the energy space equipped with the weak topology are also investigated. 相似文献
36.
作者在三维全空间中考虑研究复Ginzburg Landau方程(CGL)的解的长时间行为。通过引入权空间,应用内插不等式和在权空间的先验估计,获得复 Ginzburg Landau方程整体解的存在性,进一步建立了整体吸引子的存在性。 相似文献
37.
J.M. González-Miranda 《Physica D: Nonlinear Phenomena》2010,239(6):322-326
We present a mechanism that explains the boundary crisis presented by the first Malasoma class P minimal chaotic flow, which is equivalent to the simplest Sprott flow. The treatment followed resorts to the existence of two invariant sets of points of the flow, in addition to the chaotic attractor, to which linear stability theory is applied. 相似文献
38.
A chaotic attractor is usually characterised by its multifractal spectrum which gives a geometric measure of its complexity. Here we present a characterisation using a minimal set of independent parameters which is uniquely determined by the underlying process that generates the attractor. The method maps the f(α) spectrum of a chaotic attractor on to that of a general two scale Cantor measure. We show that the mapping can be done in practice with reasonable accuracy for many of the standard chaotic attractors. In order to implement this procedure, we also propose a generalisation of the standard equations for the two scale Cantor set in one dimension to that in higher dimensions. Another interesting result we have obtained both theoretically and numerically is that, the f(α) characterisation gives information only up to two scales, even when the underlying process generating the multifractal involves more than two scales. 相似文献
39.
In this Letter, a novel method is developed for generating grid multi-scroll chaotic attractors using switching piecewise linear controller. First, a third-order linear system is designed to ensure that its unique equilibrium point belongs to a saddle-focus type with index 2 and the corresponding eigenvalues satisfy Shilnikov conditions. Then, by three different types of switching control strategies, the equilibrium point can be extended along both xy plane and z axis direction, so as to generate grid multi-scroll chaotic attractors. The dynamical behaviors are further analyzed. Moreover, an improved module-based circuit is designed for realizing 5×3 and 4×4 grid scroll chaotic attractors, and the experimental results are also obtained, which is consistent with the numerical simulations. 相似文献
40.
This paper investigates the dynamical behaviour of the Liu system with time delayed feedback. Two typical situations are considered and the effect of time-delay parameter on the dynamics of the system is discussed. It is shown that the Liu system with time delayed feedback may exhibit interesting and extremely rich dynamical behaviour. The evolution of the dynamics is shown to be complex with varying time-delay parameter. Moreover, the strange attractor like ‘wormhole' is detected via numerical simulations. 相似文献