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171.
C. A. Morales M. J. Pacifico E. R. Pujals 《Proceedings of the American Mathematical Society》1999,127(11):3393-3401
We construct a class of vector fields on 3-manifolds containing the hyperbolic ones and the geometric Lorenz attractor. Conversely, we shall prove that nonhyperbolic systems in this class resemble the Lorenz attractor: they have Lorenz-like singularities accumulated by periodic orbits and they cannot be approximated by flows with nonhyperbolic critical elements.
172.
林宗池 《应用数学和力学(英文版)》1980,1(3):357-370
This paper is the continuation of article [7]. It gives further results about the asymptotic expression for the solution of higher order elliptic equation in the case of boundary perturbation combined with operator perturbation. When unperturbed problemA
0 is not on the spectrum, the asymptotic expression for the solution of perturbation problemA
may be expanded with respect to the small parameter . WhileA
0 is on the spectrum, the asymptotic expression of the solution contains negative powers of the small parameter . The approximation of arbitrary order to the solution is considered and the recursive formula for the general term and the estimation of remainder term are given. 相似文献
173.
V. S. Anishchenko A. S. Kopeikin J. Kurths T. E. Vadivasova G. I. Strelkova 《Physics letters. A》2000,270(6):301-307
On the basis of method [1] proposed for diagnosing 2-dimensional chaotic saddles we present a numerical procedure to distinguish hyperbolic and nonhyperbolic chaotic attractors in three-dimensional flow systems. This technique is based on calculating the angles between stable and unstable manifolds along a chaotic trajectory in R3. We show for three-dimensional flow systems that this serves as an efficient characteristic for exploring chaotic differential systems. We also analyze the effect of noise on the structure of angle distribution for both 2-dimensional invertible maps and a 3-dimensional continuous system. 相似文献
174.
Antonio Algaba Manuel Merino Bo-Wei Qin Alejandro J. Rodríguez-Luis 《Physics letters. A》2019,383(13):1441-1449
A simple three-dimensional time-reversible system of ODEs with quadratic nonlinearities is considered in a recent paper by Sprott (2014). The author finds in this system, that has no equilibria, the coexistence of a strange attractor and invariant tori. The goal of this letter is to justify theoretically the existence of infinite invariant tori and chaotic attractors. For this purpose we embed the original system in a one-parameter family of reversible systems. This allows to demonstrate the presence of a Hopf-zero bifurcation that implies the birth of an elliptic periodic orbit. Thus, the application of the KAM theory guarantees the existence of an extremely complex dynamics with periodic, quasiperiodic and chaotic motions. Our theoretical study is complemented with some numerical results. Several bifurcation diagrams make clear the rich dynamics organized around a so-called noose bifurcation where, among other scenarios, cascades of period-doubling bifurcations also originate chaotic attractors. Moreover, a cross section and other numerical simulations are also presented to illustrate the KAM dynamics exhibited by this system. 相似文献
176.
177.
一类广义Boussinesq方程的整体弱解和整体弱吸引子 总被引:1,自引:0,他引:1
本文证明了一类广义Boussinesq方程的整体弱解和整体弱吸引子的存在性。 相似文献
178.
增广Lü系统是仅含有两个控制参数的三维混沌系统,可产生一个伪四翼吸引子.利用混沌反控制方法,通过在增广Lü系统中引入一个简单的线性状态控制器,提出了一个新三维混沌系统——广义增广Lü系统.新系统实现了一个真正的具有复合结构的四翼吸引子,它包含了两个镜像对称的子系统.理论分析、数值仿真和电路实验证明了广义增广Lü系统四翼吸引子的存在性,也阐述了广义增广Lü系统有着较增广Lü系统更加丰富的动力学特性.
关键词:
广义增广Lü系统
四翼吸引子
数值仿真
电路实验 相似文献
179.
Alexander Rybko Senya Shlosman Alexander Vladimirov 《Journal of statistical physics》2009,134(1):67-104
We present an example of a highly connected closed network of servers, where the time correlations do not vanish in the infinite
volume limit. The limiting interacting particle system behaves in a periodic manner. This phenomenon is similar to the continuous
symmetry breaking at low temperatures in statistical mechanics, with the average load playing the role of the inverse temperature. 相似文献
180.
G. S. Khadekar Rupali Wanjari Cenap Ozel 《International Journal of Theoretical Physics》2009,48(9):2550-2557
In this study we have analyzed the Kaluza-Klein type Robertson Walker (RW) cosmological model by considering variable cosmological
constant term Λ of the form:
,
and Λ∼ρ in the presence of strange quark matter with domain wall. The various physical aspects of the model are also discussed. 相似文献