Global Bifurcation of a Perturbed Double-Homoclinic Loop

This paper deals with a kind of fourth degree systems with perturbations. By using the method of multi-parameter perturbation theory and qualitative analysis, it is proved that the system can have six limit cycles.     

一类三次Kolmogorov系统的极限环分支

本文研究了一类三次Kolmogorov系统，得出了该系统可分支出三个极限环，且其中有两个是稳定的，同时给出了其中心条件.     

一类五次系统的全局分支

本文利用多参数扰动法并进行定性分析,对一类三次哈密尔顿系统进行五次扰动,得到了五个极限环.     

以抛物弓形为边界的周期环域的三次系统的Poincaré分支

本文以抛物弓形为边界的周期环域的三次系统的Poincaré分支为例,说明具有相同边界的周期环域的相同次数的多项式系统的Poincaré分支,由于周期环域内闭轨的不同,它们所对应的Abel积分也不同,所以它们的Poincaré分支所能分支出极限环的个数也是不同的.     

一类三次微分系统的极限环

研究一类三次微分系统极限环的个数。给出了极限环的不存在性和唯一性的判别法．后者是利用一条无功二次曲线，它的方程是所论系统的发散量等于零。     

具有三次曲线解xy2+y=x3的中心对称三次系统极限环的存在性

本文证明了具有三次曲线解ｘｙ²＋ｙ＝ｘ³的中心对称三次系统的极限环存在，而且至少可以存在四个极限环，它们作（２，２）分布．从而纠正了文［１］的结论     

具有全局中心的三次Hamilton系统的Poincaré分支

本文讨论一类具有全局中心的三次:Hamilton系统的Poincare分支,证明了 其Poincare分支最多可以产生两个极限环,而且可以产生两个极限环.     

Existence of Limit Cycles for a Cubic Kolmogorov System with a Hyperbolic Solution

When we discuss some problems in bio-mathematics,we often meet cubicKolmogorov systems.For general type of Kolmogorov systems,the qualitative analysisis very difficult. Usually,one discusses some special type of cubic Kolmogorovsystems,for example,cubic Kolmogorov systems with an algebraic curve solution.Firstly,the existence oflimitcycles fora cubic Kolmogorov system with quadratic curvesolution was studied.In article[1 ] ,though the author proved the cubic Kolmogorovsystem with a solution…     

一类对称五次系统的极限环分支

对一类对称五次近Hamilton系统在五次对称摄动下产生的极限环数目进行了研究.通过多参数摄动理论和定性分析,得到这类对称摄动下的五次系统至少可以存在28个极限环.     

一类具细焦点的三次系统极限环的唯一性

继续相关文献的工作,给出与二次系统Ⅰ相伴的一类三次系统在奇点N(0,1/n)的焦点量公式,证明了系统在细焦点N外围至多有一个极限环,同时证明了当N或O为细焦点时,系统在另一个焦点外围无极限环,结合相关文献的结论,说明了具有细焦点的该系统在全平面至多有一个极限环.     

具有四次曲线解的Kolmogorov三次系统极限环的存在性问题

证明了具有退化四次曲线解[y-(x-1)2]2=0的Kolmogorov三次系统是可以存在极限环的.并举出了具体的例子.     

一类单中心Hamilton系统在三次扰动下的Poincare分岔

使用一阶Mel‘nikov函数讨论了一类具有以抛物线与直线为边界的周期环域的单中心二次Hamilton系统的三次扰动下的Poincare分岔,得到其Poincare分岔最多可以产生两个极限环。     

中心对称三次系统的一类双纽线有界周期环域的poincare分支

证明中心对称三次系统的一类双纽线有界周期环域的 poincare分支至少可以出现作对称 (3,3)分布的六个极限环 .     

Bifurcation and Isochronicity at Infinity in a Class of Cubic Polynomial Vector Fields

In this paper, we study the appearance of limit cycles from the equator and isochronicity of infinity in polynomial vector fields with no singular points at infinity. We give a recursive formula to compute the singular point quantities of a class of cubic polynomial systems, which is used to calculate the first seven singular point quantities. Further, we prove that such a cubic vector field can have maximal seven limit cycles in the neighborhood of infinity. We actually and construct a system that has seven limit cycles. The positions of these limit cycles can be given exactly without constructing the Poincare cycle fields. The technique employed in this work is essentially different from the previously widely used ones. Finally, the isochronous center conditions at infinity are given.     

一类具Holling-IV的捕食-食饵系统的Hopf分岔

研究了具有简化Holling-IV功能反应函数捕食-食饵模型二阶细焦点的Hopf分岔问题.运用隐函数存在定理,证明了该模型二阶细焦点确定的系数经扰动后在其邻域内有二个极限环.     

Bifurcation analysis of a plant-herbivore model with toxin-determined functional response

A system of ordinary differential equations is considered which models the plant-herbivore interactions mediated by a toxin-determined functional response. The new functional response is a modification of the traditional Holling Type II functional response by explicitly including a reduction in the consumption of plants by the herbivore due to chemical defenses. A detailed bifurcation analysis of the system reveals a rich array of possible behaviors including cyclical dynamics through Hopf bifurcations and homoclinic bifurcation. The results are obtained not only analytically but also confirmed and extended numerically.     

一类三次kolmogorov系统的极限环

本研究一类三次kolmogorov系统解的定性行为，给出了系统解的有界性与极限环存在性的充分条件。     

Bifurcation of limit cycles near equivariant compound cycles

In this paper we study some equivariant systems on the plane. We first give some criteria for the outer or inner stability of compound cycles of these systems. Then we investigate the number of limit cycles which appear near a compound cycle of a Hamiltonian equivariant system under equivariant perturbations. In the last part of the paper we present an application of our general theory to show that a Z3 equivariant system can have 13 limit cycles.     

THE PROBLEM OF LIMIT CYCLES FOR A LIENARD TYPE CUBIC SYSTEM

The purpose of this paper is to study a general Lienard type cubic system with one antisaddle and two saddles. We give some results of the existence and uniqueness of limit cycles as well as the evolution of limit cycles around the antisaddle for system (2) in the following when parameter a1 changes.     

The number and distributions of limit cycles for a class of cubic near-Hamiltonian systems

This paper concerns with the number of limit cycles for a cubic Hamiltonian system under cubic perturbation. The fact that there exist 9-11 limit cycles is proved. The different distributions of limit cycles are given by using methods of bifurcation theory and qualitative analysis, among which two distributions of eleven limit cycles are new.