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广义指数二分性与微分方程的不变流形 被引量:5
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作者 张伟年 《数学进展》 CSCD 北大核心 1993年第1期1-45,共45页
用 Hadamar和 Bogoliubov的方法,在常微分方程、泛函微分方程以及半线性抛物型方程所能满足的条件下对Banach或Hilbert空间上的非自治抽象微分方程建立了不变流形理论。首先,对相应的线性方程提出了“广义指数二分性”概念并讨论了它和... 用 Hadamar和 Bogoliubov的方法,在常微分方程、泛函微分方程以及半线性抛物型方程所能满足的条件下对Banach或Hilbert空间上的非自治抽象微分方程建立了不变流形理论。首先,对相应的线性方程提出了“广义指数二分性”概念并讨论了它和线性方程谱的关系,然后,我们给出了不变流形存在性结论以及强稳定(不稳定)流形、弱稳定(不稳定)流形和弱双曲流形的分类。进而,我们对这些不变流形给出了C^k光滑性、周期性、概周期性和吸斥性的结论。 展开更多
关键词 广义 指数二分性 微分方程
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双尺度收敛和拟线性抛物方程的均匀化 被引量:6
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作者 张兴友 《应用数学学报》 CSCD 北大核心 1996年第3期431-444,共14页
利用Fourier分析的某些技巧,得到殆周期国数的一些新性质,在此基础上将均匀化理论中的双尺度收敛方法推广到殆周期振荡的情形.然后利用一些新技巧讨论了殆周期振荡的拟线性方程的均匀化问题,得到了相应的弱收敛和纠正子结果.
关键词 均匀化 双尺度收敛 抛物型方程 拟线性
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Existence and global attractivity of unique positive almost periodic solution for a model of hematopoiesis 被引量:7
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作者 YANG Xi-tao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期25-34,共10页
Sufficient conditions are obtained which guarantee the uniform persistence and global attractivity of solutions for the model of hematopoiesis. Then some criteria are established for the existence, uniqueness and glob... Sufficient conditions are obtained which guarantee the uniform persistence and global attractivity of solutions for the model of hematopoiesis. Then some criteria are established for the existence, uniqueness and global attractivity of almost periodic solutions of almost periodic system. 展开更多
关键词 almost periodicity global attractivity uniform persistence.
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Banach空间上一类非稠定时滞微分方程的概自守性
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作者 郑兰玲 丁惠生 《数学物理学报(A辑)》 CSCD 北大核心 2024年第2期361-375,共15页
该文主要研究Banach空间X上一类有限时滞微分方程u'(t)=Au(t)+Lu_(t)+f(t,u_(t)),t∈R的概自守性,其中A为非稠定的Hille-Yosida算子,L为有界线性算子,f为二元S^(p)-概自守函数.相比已有相关研究结果,该文不要求Hille-Yosida算子生... 该文主要研究Banach空间X上一类有限时滞微分方程u'(t)=Au(t)+Lu_(t)+f(t,u_(t)),t∈R的概自守性,其中A为非稠定的Hille-Yosida算子,L为有界线性算子,f为二元S^(p)-概自守函数.相比已有相关研究结果,该文不要求Hille-Yosida算子生成的半群具有紧性,且仅在f具有更弱的Lipschitz假设和比概自守性更弱的S^(p)-概自守性假设下,得到了上述时滞微分方程的解具有紧概自守性(比概自守性更强).此外,该文还把抽象结果应用到一类来源于年龄结构模型的偏微分方程. 展开更多
关键词 Hille-Yosida算子 概自守性 概周期性 抽象时滞微分方程
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A Spectrum Relation of Almost Periodic Solution of Second Order Scalar Functional Differential Equations with Piecewise Constant Argument 被引量:4
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作者 Li WANG Rong YUAN Chuan Yi ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第11期2275-2284,共10页
In this paper, the spectrum relation of almost periodic solution for the equation (x(t) +px(t - 1))" = qx([t]) + f(Q is investigated. Although this has been discussed in an article, some counterexamples ar... In this paper, the spectrum relation of almost periodic solution for the equation (x(t) +px(t - 1))" = qx([t]) + f(Q is investigated. Although this has been discussed in an article, some counterexamples are constructed to show that some part of the spectrum inclusion in that article is not correct. The key point which causes such problem is found out. A new statement is formulated and proved. 展开更多
关键词 Neutral delay-differential equation piecewise constant argument almost periodicity SPECTRUM
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ALMOST PERIODICITY AND EQUICONTINUITY OF THE TOPOLOGICAL TRANSFORMATION GROUP 被引量:1
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作者 Li Zhicong Li Juntao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期467-472,共6页
In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transf... In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transformation group is topologically equivalent to an isometric one if it is uniformly equicontinuous. 展开更多
关键词 uniform space topological transformation group EQUICONTINUITY almost periodicity compactly almost periodicity.
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The Existence of Positive Almost Periodic Type Solutions for Some Nonlinear Delay Integral Equations 被引量:3
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作者 Bin XU Rong YUAN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第6期1351-1360,共10页
This paper presents the conditions of existence of positive almost periodic type solutions for some nonlinear delay integral equations, by using a fixed point theorem in the mixed monotone operators (Ma, Y.: On a cl... This paper presents the conditions of existence of positive almost periodic type solutions for some nonlinear delay integral equations, by using a fixed point theorem in the mixed monotone operators (Ma, Y.: On a class of mixed monotone operators and a kind of two-point bounded value problem. Indian J. Math., 41(2), 211-220 (1999]]. Some known results are operators. 展开更多
关键词 almost periodicity delay integral equation mixed monotone operators
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遍历性及其应用──(Ⅰ)基本性质(英) 被引量:3
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作者 张传义 《应用泛函分析学报》 CSCD 1999年第1期28-39,共12页
在一般意义下,给出了函数的遍历性定义.指出遍历函数是比概周期函数、渐近概周期函数及弱概周期函数更广的一类函数.文章讨论了遍历函数的一些性质,其中一个主要结果是给出了一个不等式的明确表达式.
关键词 遍历性 概周期性 微分方程
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EXISTENCE OF ALMOST PERIODIC SOLUTIONS TO SOME SEMI-LINEAR STOCHASTIC INTEGRO-DIFFERENTIAL EQUATIONS 被引量:2
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作者 Weiguo Liu Jiaowan Luo 《Annals of Differential Equations》 2013年第1期34-43,共10页
In this paper, in the sense of the definition of almost periodicity given by H.Bohr using fixed-point principle, we investigate the existence and uniqueness of quadratic mean almost periodic solutions to semi-linear s... In this paper, in the sense of the definition of almost periodicity given by H.Bohr using fixed-point principle, we investigate the existence and uniqueness of quadratic mean almost periodic solutions to semi-linear stochastic integro-differential evolution equations associated with abstract Volterra equations. Some examples are also given to illustrate our theory. 展开更多
关键词 immediate norm continuity almost periodicity semi-linear stochastic integro-differential equations
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一类非线性Duffing方程概周期解的存在性 被引量:3
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作者 张留伟 徐远通 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第4期6-10,共5页
研究了一类广义非线性Duffing方程概周期解的存在性。通过Lyapunov函数建立辅助线性方程的指数型二分性,在此基础上,选取适当的函数空间,利用不动点定理,得到广义非线性Duffing有界解的存在性,再次利用Lyapunov函数,得到其概周期解的存... 研究了一类广义非线性Duffing方程概周期解的存在性。通过Lyapunov函数建立辅助线性方程的指数型二分性,在此基础上,选取适当的函数空间,利用不动点定理,得到广义非线性Duffing有界解的存在性,再次利用Lyapunov函数,得到其概周期解的存在性和模包含关系。 展开更多
关键词 DUFFING方程 概周期 指数型二分性 LYAPUNOV函数
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Correction and Supplement to Approach for a Proof of Riemann Hypothesis by Second Mean-Value Theorem 被引量:1
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2017年第3期263-276,共14页
From the theorem 1 formulated in [1], a set of functions of measure zero within the set of all corresponding functions has to be excluded. These are the cases where the Omega functions &Omega;(u)?are piece-wise co... From the theorem 1 formulated in [1], a set of functions of measure zero within the set of all corresponding functions has to be excluded. These are the cases where the Omega functions &Omega;(u)?are piece-wise constant on intervals of equal length and non-increasing due to application of second mean-value theorem or, correspondingly, where for the Xi functions &Xi;(z)?the functions &Xi;(y)y are periodic functions on the imaginary axis y with?z=x+iy. This does not touch the results for the Omega function to the Riemann hypothesis by application of the second mean-value theorem of calculus and the majority of other Omega functions in the suppositions, but makes their derivation correct. The corresponding calculations together with a short recapitulation of the main steps to the basic equations for the restrictions of the mean-value functions and the application to piece-wise constant Omega functions (staircase functions) are represented. 展开更多
关键词 RIEMANN HYPOTHESIS ZEROS of Modified BESSEL FUNCTIONS almost-periodic FUNCTIONS
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WEIGHTED PSEUDO ALMOST-PERIODIC SOLUTIONS OF SHUNTING INHIBITORY CELLULAR NEURAL NETWORKS WITH MIXED DELAYS 被引量:1
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作者 Mohammed Salah M'HAMDI Chaouki AOUITI +2 位作者 Abderrahmane TOUATI Adel M. ALIMI Vaclav SNASEL 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1662-1682,共21页
In this paper, we prove the existence and the global exponential stability of the unique weighted pseudo almost-periodic solution of shunting inhibitory cellular neural networks with mixed time-varying delays comprisi... In this paper, we prove the existence and the global exponential stability of the unique weighted pseudo almost-periodic solution of shunting inhibitory cellular neural networks with mixed time-varying delays comprising different discrete and distributed time delays. Some sufficient conditions are given for the existence and the global exponential stability of the weighted pseudo almost-periodic solution by employing fixed point theorem and differential inequality techniques. The results of this paper complement the previously known ones. Finally, an illustrative example is given to demonstrate the effectiveness of our results. 展开更多
关键词 weighted pseudo almost-periodic solution shunting inhibitory cellular neuralnetworks mixed delays global exponential stability
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Banach空间中立型泛函微分方程的概周期温和解 被引量:2
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作者 张留伟 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第1期30-34,共5页
借助于一般的谱分解技巧,利用线性算子半群理论研究了Banach空间X中立型泛函微分方程一致连续的有界温和解的存在性与唯一性,得到了当X没有与c0同构的子空间时方程概周期温和解存在与唯一的谱条件,推广了线性微分方程的现有结果。
关键词 概周期 Carleman谱 线性算子半群 中立型泛函微分方程
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一类时滞捕食-食饵系统的概周期解的存在唯一性和全局吸引性 被引量:2
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作者 杨喜陶 《生物数学学报》 2016年第4期527-537,共11页
利用微分不等式及Liapunov泛函,研究了一类具有时滞和Modified Leslie-Gower HollingⅡ功能性反应捕食-食饵系统,获得了系统一致持久及解全局吸引的充分条件,对于这类概周期系统,建立了存在全局吸引的唯一正概周期解的准则.
关键词 时滞 LIAPUNOV泛函 一致持久 全局吸引 概周期
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Attractivity and Oscillation of Almost-periodic Solution for a Discrete Model of Hematopoiesis
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作者 HONG Peng-hua WENG Pei-xuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期20-26,共7页
By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity ... By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity and oscillation are investigated. 展开更多
关键词 discrete model of hematopoiesis almost-periodic solution existence ATTRACTIVITY OSCILLATION
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具有逐段常量的三阶微分方程解的周期性和概周期性(英文)
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作者 张宝 李洪旭 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第1期1-6,共6页
本文研究具有逐段常量的三阶微分方程x^(t)- a^2x′(t)=bx(2[t+1/2]),通过方程对应的差分方程给出了方程解的具体形式, 并由此得到了关于方程解的周期性和概周期性的一些结果.
关键词 三阶微分方程 逐段常量 周期性 概周期性
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差分方程解的稳定性、有界性及概周期解的存在性 被引量:1
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作者 杨喜陶 《数学物理学报(A辑)》 CSCD 北大核心 2008年第5期870-878,共9页
作者通过Liapunov泛函建立了一类高维差分方程解一致稳定、一致渐近稳定及指数渐近稳定的充要条件.此外,作者还证明了解的一致渐近稳定性蕴含解的有界性,同时也给出了概周期差分方程存在概周期解的一个充分条件.
关键词 差分方程 稳定性 有界性 概周期 LIAPUNOV泛函
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函数f(x)与|f(x)|概周期性研究
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作者 李冬辉 《河南教育学院学报(自然科学版)》 2010年第3期8-9,共2页
给出了函数的概周期定义和两个简单性质,研究了函数f(x)与绝对值|f(x)|函数概周期性之间的关系,得出了相应的结论.
关键词 函数 概周期 关系 周期性 绝对值
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Existence and exponential stability of almost-periodic solutions for MAM neural network with distributed delays on time scales 被引量:1
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作者 GAO Jin WANG Qi-ru LIN Yuan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第1期70-82,共13页
This paper is concerned with multidirectional associative memory neural network with distributed delays on almost-periodic time scales.Some sufficient conditions on the existence,uniqueness and the global exponential ... This paper is concerned with multidirectional associative memory neural network with distributed delays on almost-periodic time scales.Some sufficient conditions on the existence,uniqueness and the global exponential stability of almost-periodic solutions are established.An example is presented to illustrate the feasibility and effectiveness of the obtained results. 展开更多
关键词 multidirectional associative memory neural networks time scales almost-periodic solutions exponential stability.
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非线性时滞积分方程正的概周期解的存在性
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作者 郭肖肖 宋小明 赵增勤 《曲阜师范大学学报(自然科学版)》 CAS 2013年第2期43-46,50,共5页
利用一种新的不动点定理及单调迭代方法,结合锥理论,研究了非线性时滞积分概周期方程,获得了其正解的存在性定理,改进和推广了某些已知结果.
关键词 混合单调算子 单调迭代技巧 概周期 锥理论
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