A NEW OSCILLATION CRITERION FOR FIRST ORDER NEUTRAL DELAY DIFFERENTIAL EQUATION

In this paper, a new sufficient condition for the oscillation of all solutions of first order neutral delay differential equations is obtained. Secondly, the result can also be extended to a general neutral differential equation, and many known results in the literatures are improved.     

带时滞机器人模型解的展开

研究一个带有时滞机器人模型解的性质, 其中机器人的动力学行为由一组含有时滞的微分方程描述.通过引入Hilbert状态空间将其写成一个发展方程, 利用半群理论得到抽象发展方程的适定性. 通过对系统算子的谱作细致分析,得到谱的渐近表达式, 并证明系统的本征函数并不构成空间的基.但我们证明了对时间大于5倍时滞时, 方程的解按照本征向量的展开式.     

GLOBAL ATTRACTIVITY FOR AMULTIPLICATIVE DELAY DIFFERENTIAL POPULATION MODEL

1IntroductionInthispaper-wegiveasufficientconditionwhichguaranteestheg10balattractivityofthepositiveequilibriumofamu1tiplicativede1ayLogisticequation:wasproposedbyHutchinson[1]asamode1fortliegrowthofasing1especies.Equation(1.2)anditsgeneralizati0nhavereceivedandc0ntinuestoreceivegreatattenti0nssee,forexample[1,2,3,8].Inanattempttointroduceseveralenioronmentalnegativefeedbackeffects,manyau-thorshaveinvestigatedthefollowingequation[4,5,7]:However-itisn0tknownwhetherseveraleniv0ronmentalintraspe…     

脉冲中立型时滞微分方程的正解的存在性

本文证明了线性脉冲中立型微分方程 [y(t)+p(t)y(t-τ)-r(t)y(t-ρ)]′+q(t)y(t-σ)=0,t≥0,t≠t_k, y(t_k~+)-y(t_k)=b_ky(t_k),k=1,2,…正解的存在性等价于一类非脉冲中立型方程正解的存在性,应用这一结果,建立了此类线性脉冲中立型微分方程正解存在性的若干充分条件。     

A DELAY DIFFERENTIAL INEQUALITY

In this paper, we obtain a slight generalization of the celebrated Halanay delay differential inequality[1]. Using this inequality, Liapunov function and vector Liapunov function, we show that our result can be applied to the stability behavior of solutions of some delay differential systems. And also, we attempt to relax some restrictions of dv/dt, which is necessary under Liapunov function's method on the delay differential systems.     

ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF NONLINEAR DELAY DIFFERENTIAL EQUATIONS

Sufficient conditions are established for the asymptotic behavior of solutionsof nonlinear delay differential equations x′(t)+sum from i=1 to m(pi(t)x(t-т_i))=F(t,x_t),t≥0where 0<т_1<т_2<…<т_m≤r,pi∈C([0,∞)),i=1,2,…,m,F∈C([0,∞)×C_0,R).C_0=C([-r,0],R)equipped with the sup norm ||·|| forsome r>0. A new result is established, some known results are improved.     

Asymptotic Properties of Delay Differential Equations

The aim of this paper is to deduce oscillatory and asymptotic behavior of the solutions of the ordinary differential equation and the delay differential equation by comparing these equations with a set of the first order advanced differential inequalities.     

OSCILLATION OF SECOND ORDER DELAY DIFFERENCE EQUATIONS

ＯＳＣＩＬＬＡＴＩＯＮＯＦＳＥＣＯＮＤＯＲＤＥＲＤＥＬＡＹＤＩＦＦＥＲＥＮＣＥＥＱＵＡＴＩＯＮＳＷａｎｇＸｉａｎｇｄｏｎｇ（王向东）（ＺｈｅｎｇｚｈｏｕＩｎｓｔｉｔｕｔｅｏｆＬｉｇｈｔＩｎｄｕｓｔｒｙ）＆ＳｈｉＹｏｎｇｓｈｅｎｇ（石永生）（Ｌｉｎｇｌ...     

Pseudo–almost‐periodic solutions for delayed differential equations with integrable dichotomies and bi–almost‐periodic Green functions

Using the existence of integrable bi–almost‐periodic Green functions of linear homogeneous differential equations and the contraction fixed point, we are able to prove the existence of almost and pseudo–almost‐periodic mild solutions under quite general hypotheses for the differential equation with constant delay in a Banach space X, where τ>0 is a fixed constant. The results extend the corresponding ones in the case of exponential dichotomy. Some examples illustrate the importance of the concepts.     

二阶线性中立时滞方程非振动解的存在性

考虑具有正负系数的中立时滞微分方程这里P∈R和τ∈(0,∞),σ1,σ2∈[0,∞)且Q1,Q2∈C([t0,∞),R+).对于上面方程非振动解的存在性,得到一个用,∫sQids <∞,i=1,2,来表达的充分条件。这个结果去掉了M.R.S.Kulenovic和S.Hadziomerspahic文中一个相当强的假设,改进了其中的相关定理.     

非线性刚性变延迟微分方程单支方法的数值稳定性

现有文献中对于非线性延迟微分方程渐近稳定性及其数值方法的稳定性研究大都局限于常延迟的情形,例如可参见匡蛟勋[1-3],黄乘明[4],Torelli[5]等人的大量工作.1994年A.Iserles[6] 首次研究了比例延迟微分方程数值方法的线性稳定性,随后有相当多的文献对比例延迟微分方程的各种数值方法的线性稳定性进行了讨论.1997年Zennaro[7]首次研究了非线性刚性变延迟微分方程的渐近稳定性,但该文中对于延迟量的限制十分苛刻,同时该文也首次研究了非线性刚性变延迟微分方程Runge-Kutta方法的非线性稳定性. 本文目的是试图在上述基础上进一步研究非线性刚性变延迟微分方程的渐近稳定性及其数值方法的稳定性.首先在第二节我们给出了非线性刚性变延迟微分方程模型问题（2.1）渐     

种群动力系统的数值解的振动性分析

本文主要研究下面动力系统的非线性延迟微分方程x't(t)+αVmx(t)p(t-τ)/βp+xp(t-τ)=λ,t≥0 数值解的振动性.这是由Mackey和Glass[1]提出来的关于动力系统疾病的方程.本文得到了数值方法振动的条件.同时对非振动的数值解的性质也做了研究,为了验证得到的结果,给出了数值算例.     

CONDITIONS FOR OSCILLATION OF NEUTRAL DELAY DIFFERENTIAL EQUATIONS

In this paper,we study one type of odd-order neutral delay differential equation. Suffcient conditions for the oscillation of every solution to this type of differential equation are given.     

OSCILLATION FOR NEUTRAL DELAY DIFFERENTIAL EQUATION WITH POSITIVE AND NEGATIVE COEFFICIENTS

In this paper, a new oscillating result is established for the first order neutral delay differential equation with positive and negative coefficients, which improves and generalizes several results in the literatures.     

A PRIORI BOUNDS FOR PERIODIC SOLUTIONS TO A FUNCTIONAL DIFFERENTIAL EQUATION WITH DELAY

A priori bounds are established for periodic solutions to a functional differential equation with delay.By means of these bounds,an existence theorem for periodic solutions is obtained using Mawhin’s continuation theorem.Our work generalizes the known result.     

含多个函数时滞的随机延迟微分方程的矩稳定性

本文考虑具有多个函数时滞的中立型随机延迟微分方程p阶矩稳定性.运用Razumikhin方法,建立了一此新的矩稳定性判别法,并以线性方程为例解释了所得判别法的应用.     

ASYMPTOTIC BEHAVIOR OF SOLUTIONS FOR A CLASS OF DELAY DIFFERENCE EQUATION

We propose a class of delay difference equation with piecewise constant nonlinearity. Such a delay difference equation can be regarded as the discrete analog of a differential equation. The convergence of solutions and the existence of asymptotically stable periodic solutions are investigated for such a class of difference equation.     

时间延迟扩散-波动分数阶微分方程有限差分方法

本文提出求解时间延迟扩散-波动分数阶微分方程有限差分方法，方程中对时间的一阶导函数用α阶（0 < α < 1） Caputo分数阶导数代替.文章中利用Lubich线性多步法对分数阶微分进行差分离散，且文章利用分段区间证明该方法是稳定的，且利用数值实验加以验证.     

OSCILLATORY AND ASYMPTOTIC BEHAVIOR OF A CLASS OF FIRST ORDER NEUTRAL DIFFERENTIAL EQUATION WITH PIECEWISE CONSTANT DELAY

The oscillatory and asymptotic behavior of a class of first order nonlinear neutral differential equation with piecewise constant delay and with diverse deviating arguments are considered. We prove that all solutions of the equation are nonoscillatory and give sufficient criteria for asymptotic behavior of nonoscillatory solutions of equation.     

超线性时滞微分方程解的振动性

研究一阶超线性时滞微分方程x′(t) p(t)[x(t—γ)]^α＝0(α＞1)解的振动性及非振动性,获得了保证其所有解振动的“almost sharp”准则,并应用所得结果于混合型时滞微分方程x′（t） ∑^ni=1pi（t）[x（t-γi]^αi=0,得到一族振动准则。