一类二次可逆系统Abel积分零点个数的上界

利用Picard-Fuchs方程法及Riccati方程法,研究了一类二次可逆系统在任意n次多项式扰动下Abel积分零点个数的线性估计,得到了当n≥3时,上界为4[2n/3]+2[2n+1/3]+[2n+2/3]+16.     

一类二次可逆系统Abel积分的零点个数估计

利用Picard-Fuchs方程法及Riccati方程法,研究了一类二次可逆系统在任意n次多项式扰动下Abel积分的零点个数估计,得出当n≥5时,上界为10[(4n+1)/3]+4[(4n)/3]+[(4n-1)/3]+13.     

一类单中心二次可积系统的Abel积分零点个数

讨论了首次积分为H(x,y)=x~k(1/2y~2+Ax~2+Bx+C)的Abel积分的代数构造,并研究了k=2时具有一个中心的平面二次可积系统在n次扰动下的Abel积分零点个数上界问题,得到了较小的上界估计,     

一类二次可逆系统周期函数的单调性

利用Picard-Fuchs方程,研究了一类二次可逆系统周期函数的单调性问题,获得了在首次积分曲线是亏格1时的二次可逆系统周期函数单调的结论.     

一类四次Hamilton函数Abel积分零点个数的估计

证明了Abel积分I(h)=∮ΓhQ(x,y)dx-P(x,y)dy的零点个数的最小上界B(2n+2)=B(2n+1)≤3[n/2]+12[(n-1)/2]+4([p]表示P的整数部分),这里n是代数曲线H(x,Y)=x2士x4+Y4=h的连通闭分支,h∈E(Γh存在的最大开区间),P(x,y),Q(x,Y)是关于x,y 的次数不超过2n+2或2n+1的实多项式.     

一类双中心平面二次系统的Abel积分零点个数

利用Abel积分与第一、第二型完全椭圆积分,本文研究一类具有两个中心奇点的平面二次系统在n次小扰动下的Abel积分零点个数上界问题,得到了较小的上界估计．     

一平面Hamilton系统的Abel积分的零点个数估计

本文讨论一平面Hamilton系统在一般n次多项式扰动下的系统的Abel积分的零点个数估计问题,得到的结论是:该系统的Abel积分的零点个数的上界为[(3n-1)/2]。     

具有幂零奇点的七次Hamilton系统Abel积分的零点个数估计

本文研究了具有幂零奇点的七次Hamilton系统的Abel积分的零点个数问题.利用Picard-Fuchs方程法,得到了Abel积分I(h)=∮_(Γh)g(x,y)dx-f(x,y)dy在(0,1/4)上零点个数B(n≤3[(n-1)/4]),其中Γ_h是H(x,y)=x~4+y~4-x~8=h,h∈(0,1/4),所定义的卵形线f(x,y)=∑(1≤4i+4j+1≤n)aijx~(4i+1)y~4j)和g(x,y)=∑(1≤4i+4j+1≤n)bijx~4iy~(4j+1)是x和y的次数不超过n的多项式.     

十一次Hamilton系统的Abelian积分零点个数的线性估计

本文研究一类十一次Hamilton系统在n次多项式扰动下的Abelian积分的零点个数问题.利用Picard-Fuchs方程法,得到这类扰动Hamilton系统的Abelian积分的零点个数的上界(计重数).     

Upper Bound of the Number of Zeros for Abelian Integrals in a Kind of Quadratic Reversible Centers of Genus One

By using the methods of Picard-Fuchs equation and Riccati equation, we study the upper bound of the number of zeros for Abelian integrals in a kind of quadratic reversible centers of genus one under polynomial perturbations of degree $n$. We obtain that the upper bound is $7[(n-3)/2]+5$ when $n\ge 5$, $8$ when $n=4$, $5$ when $n=3$, $4$ when $n=2$, and $0$ when $n=1$ or $n=0$, which linearly depends on $n$.     

具有蝴蝶型相图的三次近Hamilton系统Abelian积分的零点个数

考虑了如下近Hamilton系统{x=2y(ax~2+2cy~2)+εf(x,y),y=2x(1-2bx~2)+εg(x,y),其中a0,c0,4bca~2,0|ε|■1,且f(x,y)和g(x,y)是关于x和y的3次多项式.得到了其相应Abelian积分孤立零点个数的上界.     

On the Number of Zeros of Abelian Integrals for aClass of Quadratic Reversible Centers of GenusOne

In this paper, using the method of Picard-Fuchs equation and Ric-cati equation, for a class of quadratic reversible centers of genus one, we re-search the upper bound of the number of zeros of Abelian integrals for thesystem (r10) under arbitrary polynomial perturbations of degree n. Our mainresult is that the upper bound is 21n - 24 (n ≥ 3), and the upper bound depends linearly on n.     

一类Hamiltion系统的Abel积分的零点个数估计

In this paper, we discuss the estimation of the number of zeros of the Abelian integral for the quadratic system which has a periodic region with a parabola and a straight line as its boundary when we perturb the system inside the class of all polynomial systems of degree n. The main result is that the upper bound for the number of zeros of the Abelian integral associated to this system is 3n-1.     

On the algebraic structure of Abelian integrals for a kind of perturbed cubic Hamiltonian systems

The finite generators of Abelian integral are obtained, where Γh is a family of closed ovals defined by H(x,y)=x²+y²+ax⁴+bx²y²+cy⁴=h, h∈Σ, ac(4ac−b²)≠0, Σ=(0,h₁) is the open interval on which Γh is defined, f(x,y), g(x,y) are real polynomials in x and y with degree 2n+1 (n?2). And an upper bound of the number of zeros of Abelian integral I(h) is given by its algebraic structure for a special case a>0, b=0, c=1.     

一平面可积三次非Hamilton系统的Abel积分

本文讨论一平面可积三次非Hamilton系统在n次多项式扰动下Abel积分零点个数上确界，得到的结论是该Abel积分的零点个数的上确界为n。     

亏格一双中心的二次可逆Lotka-Volterra系统的二次扰动

该文研究在二次扰动下,亏格一双中心的二次可逆Lotka-Volterra系统周期环域产生极限环的个数问题.证明在二次扰动下,二次可逆Lotka-Volterra系统(rlv5)的周期环域产生极限环的个数不超过3.