共查询到20条相似文献,搜索用时 62 毫秒
1.
Lienard方程周期解、概周期解的存在性 总被引:20,自引:2,他引:18
本文考虑Lienard方程x”十f(x)x’+g(x)=e(t),我们得到:当且时,对于任意周期或概周期。数e(t),它有周期或概周期解.而对于Lienard方程x”+f(x)x’+cx=e(t),我们得到:当c>0且时,对于任意周期、或概周期函数e(t),它有周期或概周期解. 相似文献
2.
Lin Faxing 《数学年刊B辑(英文版)》1990,11(4):525-535
In this paper, it is obtained that a periodic system has an almost periodic solution if it has a solution x=\phi(t) uniformly stable with respect to \Omega_\phi ,and has a periodic solution if x=\phi(t) is weakly uniformly asymptotically stable with respect to \Omega_\phi. Meanwhile, it is also obtained that a uniformly almost periodic system has an almost periodic solution if it has a solution x=\phi(t) uniformly asymptotically stable with respect to A_\phi^j. 相似文献
3.
4.
Lin Zhengsheng 《数学年刊B辑(英文版)》1984,5(3):363-373
By using the exponential dichotomy and the averaging method,a perturbation theoryis established for the almost periodic solutions of an almost differential system.Suppose that the almost periodic differential system(dx)/(dt)=f(x,t) ε~2g(x,t,ε)(1)has an almost periodic solution x=x_0(t,M)for ε=0,where M=(m_1,…,m_k)is theparameter vector.The author discusses the conditions under which(1)has an almostperiodic solution x=x(t,ε)such that x(t,ε)=x_0(t,M)holds uniformly.The results obtained are quite complete. 相似文献
5.
A nonautonomous stage-structured two species model with time delay anddiffusion is considered. It is shown that the system is uniformly persistent undersome conditions. By discussing the independent subsystem, more brief sufficientconditions are drawn for a unique positive periodic solution which is globallyattractive and the existence of the positive almost periodic solution which isuniformly asymptotically stable by the Razumikhin function method. 相似文献
6.
一类中立型泛函微分方程的周期解 总被引:9,自引:0,他引:9
本文考虑一类中立型微分差分方程x′(t)+Cx′(t-r)=A(t,x)x(t)+f(t,x(t-r)),利用矩阵测度结合不动点定理的方法,得到其周期解存在的充分条件,所得定理改进或推广了「1-3」中的有关结果。 相似文献
7.
Zhu Yanling 《Annals of Differential Equations》2007,23(1):119-126
By using the theory of coincidence degree, we study a kind of periodic solution to p-Laplacian differential equation with a deviating argument such as ((?)p(x'(t)))' f(x(t)) g(x(t - r(t))) = e(t), a result on the existence of periodic solution is obtained. 相似文献
8.
本文考虑 Lienard方程 x″+f (x) x′+g(x) =e(t) ,我们得到 :当 -∞ 0且 0 相似文献
9.
10.
一类二阶泛函微分方程周期解存在性问题 总被引:18,自引:0,他引:18
利用重合度理论研究一类二阶泛函微分方程x″(t)+f(t,x_t)x′~n+β(t)g(x(t-τ(t)))=p(t)的周期解问题,本文得到了周期解存在的新的结果。 相似文献
11.
12.
13.
A GENERALIZATION OF A PROPOSITION ON EXPONENTIAL DICHOTOMY 总被引:2,自引:0,他引:2
1 Introduction and Statement of TheoremConsider systemx' = A(t)x f(t, x), (l.1)where x E R", A(t) is a continuous matrix function, f: R x R" - R" is acontinuous function.We say that the linear differential equation X' = A(t)x admits an exponential dichotomy, if it has a fundamental matrix X(t) such thatIX(t)PX--'(s)l 5 K' e--a(t--s) for s S t,(1.2)IX(t)(I -- P)X--'(s)I 5 K' e--a(s--t) for s 2 t, (1'2)where P is a projection (P' = P), K and a are positive constants.Remark Without … 相似文献
14.
Luo Dingjun 《数学年刊B辑(英文版)》1992,13(3):341-349
The existence of periodic solutions of the nonlinear system $[\mathop x\limits^{..} + f(x)\mathop x\limits^. + g(t,x) = c(t)\]$ is studied by using the theory of nonhomogeneous linear periodic systems and the Schauder fixed point theorem. 相似文献
15.
Liénard方程的比较原理 总被引:3,自引:0,他引:3
本文证明了一个比较原理,使方程x" f(x)x' g(x)=0的周期解存在性定理可以用来判断方程x" h(x,x')x' g(x)=0的周期解的存在性. 相似文献
16.
一类二阶具偏差变元的微分方程周期解 总被引:29,自引:0,他引:29
本文利用重合度理论研究一类二阶具偏差变元的微分方程x''(t)+f(t,x(t),x(t-τ0(t)))x'(t)+β(t)g(x(t-τ1(t)))=p(t)的周期解问题,得到了存在周期解的新的结果. 相似文献
17.
具无限时滞的非线性积分微分方程的周期解 总被引:11,自引:0,他引:11
本文考虑具无限时滞非线性积分微分方程和其中t∈R,T≥0是常数,x∈Rn;A(t,x),C(t,s)为n×n连续的函数矩阵;f(t,x),g(t,x),b(t)是n维连续向量.本文利用线性系统的指数型二分性理论和不动点定理研究此系统,建立了保证其周期解存在性.唯一性的充分条件.得到了一些新的结果,推广了相关文献的主要结果. 相似文献
18.
<正> 考虑拟线性微分方程系 dX/dt=A(t)X十f(t)十μF(X,t,μ),(1)其中A(t)是t的n阶连续方阵,x是n向量,f(t),F(X,t,μ)是各变量的n连续向量,μ真是小参数. 当A(t)是常数方阵,f(t),F(X,t,μ)是t的一致概周期向量函数,Coddington,Levinson,等人建立了(1)的周期解的存在定理.此可参考[1]和[2].对A(t)为常数方阵,f(t),F(X,t,μ)是t的一致概周期向量函数,更进一步建立了(1)的概周期解的存在定理. 相似文献
19.
Huang Qichang 《数学年刊B辑(英文版)》1984,5(3):311-318
This paper deal with the existence of periodic solutions of the nonlinear cscillation equation
$$\[\mathop x\limits^{ \cdot \cdot } + f(x)\varphi (x) + \psi (x)\eta (x) = 0\begin{array}{*{20}{c}}
{}&{(3)}
\end{array}\]$$
The author offers a method which can reduce (3) into system
$$\[\mathop x\limits^ \cdot = h(y) - e(y)F(x),\mathop y\limits^ \cdot = - g(x)\begin{array}{*{20}{c}}
{}&{(9)}
\end{array}\]$$
Some sufficient condition for the existence of the limit cycles of (9) are obtained. These results generalize the results in [1,2,3,4,5,6]. 相似文献
20.
具时滞的高维周期系统周期解的存在性与唯一性 总被引:24,自引:3,他引:21
本文考虑了具时滞的高维周期系统x’(t)=A(t,x(t))x(t)+f(t,x(t-r)),其中(t,x)∈R×R~n,A(t,x)是n×n连续矩阵,f(t,x)是n维连续向量,且A(t+T,x)=A(T,x),f(t十T,x)=f(t,x).利用不动点方法,建立了保证其T周期解的存在性及唯一性的充分条件.所得结果推广、改进了文[1-3]的主要结果. 相似文献