一类异宿环分支极限环的唯一性

本文研究平面上一类两点或三点异宿环附近极限环的分支,在一简洁条件下证明了异宿环分支极限环的唯一性,并给出了极限环唯一存在的充要条件.作为对三维余维2分支的应用,解决了所出现的两点异宿环产生唯一极限环的问题.     

高维空间中连接双曲鞍点的异宿环的稳定性

本文考虑任意有限维空间连接两个双曲鞍点的非扭曲异宿环的稳定性问题.在可定义Poincar′e映射的条件下,给出了异宿环在其部分邻域内是渐近稳定的判据,将3维系统鞍点异宿环的稳定性结果推广到了m+n+2维空间中的非扭曲的2-鞍点异宿环,其中m 0,n 0.通过在两个鞍点充分小邻域内,给出系统在适当的线性变换下的第一个规范型,接着采用将局部稳定流形和不稳定流形拉直的变换建立了第二个规范型.然后,在鞍点P1,P2的小邻域内适当选取两个异宿轨道的横截面,并分别分两部分来构造流映射.在鞍点P1,P2的小邻域内,本质上我们利用线性近似系统的流来构造奇异流映射的主部,而在鞍点的邻域外的异宿轨道的小管状邻域内,则用近似于一个非奇异矩阵的微分同胚来获得正则流映射.将四者复合即得到定义于P1小邻域内某横截面上的Poincar′e映射.最后,我们通过技巧性地估计向量的模,给出了在横截面上Poincar′e映射的初始点与首次回归点离异宿轨道与横截面交点的距离之比,由此得到关于非扭曲2-点异宿环的非常简洁的稳定性判据.     

Banach空间中正则非退化异宿环的Lipschitz 扰动

本文研究Banach空间上离散动力系统的Lipschitz扰动.设f,g是Banach空间(X,||·||)上的连续自映射.如果f具有正则非退化返回排斥子或正则非退化异宿环且g是f的Lipschitz小扰动,则g也有正则非退化返回排斥子或正则非退化异宿环.另外,本文还证明完备度量空间中正则非退化异宿环蕴含正则非退化返回...     

同宿、异宿环分支出极限环的唯一性

本文在一简洁条件下证明任一含细鞍点的孤立同宿环及对称的双同宿环和两点异宿环至多产生一个极限环。     

一类异宿环分支问题中极限环的唯一性

在具余维２奇点的四维系统的两参数开折的研究中出现一类三点异宿环的扰动分支,对此异宿环产生极限环的唯一性一直未得到完整的解决,本文圆满地解决了这一问题,并获得了全局分支中极限环的唯一性。     

三点粗异宿环分支

本文研究高维系统连接三个鞍点的粗异宿环的分支问题.在一些横截性条件和非扭曲条件下,获得了Γ附近的1-异宿三点环, 1-异宿两点环、 1-同宿环和1-周期轨的存在性,唯一性和不共存性.同时给出了分支曲面和存在域.上述结果被进一步推广到连接l个鞍点的异宿环的情况,其中l≥2.     

一类两点异宿环的扰动分支

设Lo为含两个双曲鞍点Si(i=1,2)的异宿环,Si的双曲比记为Tio(i=1,2),Mourtada在1994年证明如果未扰动系统与被扰系统均为C∞的,则当r10r20≠1时,Lo至多产生两个极限环.本文对C3系统证明了这一结论.     

格点动力系统中的异宿环

讨论格点动力系统中空间混沌出现的一个判据——异宿环.证明了若格点动力系统有渐近稳定的异宿环,则系统有渐近稳定的同宿点,从而系统有空间混沌.     

具有临界两点异宿环的二次系统

本文给出二次系统存在临界两点异宿环的充要条件,并证明二次系统的临界两点异宿环必由双曲线的一支和直线或由椭圆和直线构成,其内部的奇点必是中心。推广所研究的这种系统,本文对[1]中提出的一个公开问题也给出了解答。     

一类两点异宿环的扰动分支

设 Ｌ０为含两个双曲鞍点 Ｓｉ（ｉ＝ １,２）的异宿环, Ｓｉ的双曲比记为ｒｉ０（ｉ＝ １,２）, Ｍｏｕｒｔａｄａ在１９９４年证明如果未扰动系统与被扰系统均为 Ｃ∞的,则当ｒ１０,２０≠１时, Ｌ０至多产生两个极限环．本文对 Ｃ３系统证明了这一结论．     

Homoclinic Cycle and Homoclinic Bifurcations of a Predator-prey Model with Impulsive State Feedback Control

In this paper, the homoclinic bifurcation of a predator-prey system with impulsive state feedback control is investigated. By using the geometry theory of semi-continuous dynamic systems, the existences of order-1 homoclinic cycle and order-1 periodic solution are obtained. Then the stability of order-1 periodic solution is studied. At last, an example is presented to illustrate the main results.     

On the $F$-expanding of Homoclinic classes

We establish a closing property for thin trapped (see Definition 1.2) homoclinic classes. Taking advantage of this property, we prove that if a homoclinic class $H(f, p)$ admits a dominated splitting $T_{H(f, p)}M=E\oplus_相似文献   

近哈密顿系统极限环的Hopf分支与同宿分支

利用Hopf与同宿两种分支中出现的系数研究了近哈密顿系统Hopf和同宿分支产生的极限环的个数与分布,得到了全局分支产生极限环的一个新的充分条件.     

一类含有参数和有理奇性哈密顿系统的同宿与异宿轨道

研究一类含有两个参数和有理奇性平面哈密顿系统的同宿与异宿轨道,该问题来源于一个关于聚合物流体剪切流动特性的研究．借助常微定性理论和不变流形分析的方法,文中给出了系统存在同宿与异宿轨道的条件,并通过数值计算检验了所得理论结果。     

Homoclinic Orbits of a Quadratic Isochronous System by the Perturbation-incremental Method

In this paper, the perturbation-incremental method is presented for the analysis of a quadratic isochronous system. This method combines the remarkable characteristics of the perturbation method and the incremental method. The first step is the perturbation method. Assume that the parameter $\lambda$ is small, i.e. $\lambda\approx0$, the initial expression of the homoclinic orbit is obtained. The second step is the parameter incremental method. By extending the solution corresponding to small parameters to large parameters, we can get the analytical-expressions of homoclinic orbits.     

Homoclinic solutions for a class of second order discrete Hamiltonian systems

Consider the second order discrete Hamiltonian systems Δ2u(n-1)-L(n)u(n) + ▽W (n, u(n)) = f(n),where n ∈ Z, u ∈ RN and W : Z × RN → R and f : Z → RN are not necessarily periodic in n. Under some comparatively general assumptions on L, W and f , we establish results on the existence of homoclinic orbits. The obtained results successfully generalize those for the scalar case.     

Bifurcation of Homoclinic Orbits with Saddle-Center Equilibrium

In this paper, the authors develop new global perturbation techniques for detecting the persistence of transversal homoclinic orbits in a more general nondegenerated system with action-angle variable. The unperturbed system is assumed to have saddle-center type equilibrium whose stable and unstable manifolds intersect in one dimensional manifold, and does not have to be completely integrable or near-integrable. By constructing local coordinate systems near the unperturbed homoclinic orbit, the conditions of existence of transversal homoclinic orbit are obtained, and the existence of periodic orbits bifurcated from homoclinic orbit is also considered.     

自治奇摄动系统的同、异宿轨道

利用指数二分性理论和泛函分析方法来处理第一变分方程在R上有多于一个非平凡有界解下的奇摄动系统的同宿轨道分支问题.利用此方法我们给出了判断奇摄动系统在退化情形下存在同、异宿轨道的Melnikov向量函数并给出了存在同宿轨道的参数估计范围.     

Bifurcation of Degenerate Homoclinic Orbits to Saddle-Center in Reversible Systems

The authors study the bifurcation of homoclinic orbits from a degenerate homoclinicorbit in reversible system. The unperturbed system is assumed to have saddlecenter type equilibrium whose stable and unstable manifolds intersect in two-dimensional manifolds. A perturbation technique for the detection of symmetric and nonsymmetric homoclinic orbits near the primary homoclinic orbits is developed. Some known results are extended.     

Bifurcation of Degenerate Homoclinic Orbits to Saddle-Center in Reversible Systems

The authors study the bifurcation of homoclinic orbits from a degenerate homoclinic orbit in reversible system. The unperturbed system is assumed to have saddle-center type equilibrium whose stable and unstable manifolds intersect in two-dimensional manifolds. A perturbation technique for the detection of symmetric and nonsymmetric homoctinic orbits near the primary homoclinic orbits is developed. Some known results are extended.