排序方式: 共有13条查询结果,搜索用时 15 毫秒
1.
通过应用拓扑度的方法, 获得了一类n阶非线性时滞微分方程2π周期解存在性的若干结论. 相似文献
2.
基于比率的三种群捕食者-食饵扩散系统的周期解 总被引:15,自引:0,他引:15
本文研究一类基于比率的三种群捕食者-食饵扩散系统,利用重合度理论建立了这类系统正周期解的存在性结果。 相似文献
3.
Abstract. The sufficient condition for the existence of 2π-periodic solutions of the following third-order functional differential equations with variable coefficients a(t)x^m(t) bx^2k-1(t) cx^12k-1(t) ∑↑2k-1i=1cix^i(t) g(x(t-τ))=p(t)=p(t 2π)is obtained. The approach is based on the abstract continuation theorem from Mawhin and the a-priori estimate of periodic solutions. 相似文献
4.
具有时滞与生理阶段结构的竞争捕食—被捕食系统的正周期解 总被引:1,自引:0,他引:1
运用重合度理论与Lyapunov泛函方法为一类具有时滞与生理阶段结构的竞争捕食-被捕食系统正周期解的存在性和全局吸引性提供了新的判别准则.文中利用积分中值定理将积分方程转换为代数方程,为拓扑度的计算提供了新的技巧;并讨论了时滞、阶段结构和竞争因素对系统正周期解的存在性和全局吸引性的影响;最后举例说明了文中的存在性条件比已有结论更简洁、全局吸引性的判别准则也是新的. 相似文献
5.
PERIODIC SOLUTIONS OF PLANAR SYSTEMS WITH FOUR DELAYS 总被引:2,自引:0,他引:2
1 IntroductionFOr the planar delay differential system with a single delay in both equationsthe first piece of research on non-constant periodic solutions was done by Ta-boas [1], where cr > 0 is a constant, fl and f2 are bounded C3 functions on R2satisfyingand the negative feedback conditions:Taboas showed that there is an ao > 0 such that fOr a > ao, there exists anon-constant periodic solution with period greater than 4. Further study onthe global existence of periodic solutions to system… 相似文献
6.
1 IlltroductionConsider the neutral de1ay differential equations with positive and negativecoefficients of the fOrm[x(t) Ac(t)x(t -- a)]' p(t)x(t -- T) -- Q(t)x(t -- 6) = 0, t 2 to, (1)where A = {--1, 1}, a > 0, T? b 2 0, c,p, Q E C([to, oo), R ), and assume thatthere exists a constant A > 0 such thatQ(t b -- T) 5 Ap*(t), p*(t) = p(t) -- Q(t 6 -- T), for t 2 max{to, to T -- b}.The study of asymptotic behavior of so1ution of (1) has had some work, seefOr example [l-9]. However,… 相似文献
7.
本文考虑Dufing型方程ax″+bx+g(x(t-τ))=p(t),用重合度理论,获得了此方程至少存在一个2π周期解的充分条件. 相似文献
8.
张正球 《Annals of Differential Equations》2004,20(2):208-214
We obtain sufficient condition for the existence of periodic solutions of thefollowing second order functional differential equationsx"(t) + ax'~α(t) + bf(x(t)) + g(x(t-T_1), x'(t-T_2))=p(t)=p(t+2π).Our approach is based on the continuation theorem of coincidence degree, andthe α-priori: estimate of periodic solutions. 相似文献
9.
10.
一类时滞Duffing型方程的周期解 总被引:34,自引:1,他引:33
本文考虑Duffing型方程αx^n bx g(x(t-r))=p(t),用重合度理论,获得了此方程至少存在一个2n周期解的充分条件. 相似文献