奇数阶中立型微分方程的线性化振动性(英文)

考虑奇数阶非线性中立型方程我们建立了方程（１．１）的一个线性化振动结论以及存在正解的充分条件．     

一阶中立型时滞微分方程的振动性

分别获得了中立型时滞微分方程「ｘ（ｔ）＋ｐｘ（ｔ－γ」’＋ｑ（ｔ）ｘ（ｔ－σ）＝０的振动性和非振动性的充分条件,其中ｐ〉０,ｑ（ｔ）是一个正的周期函数。     

中立型时滞微分方程解的振动性

1.引言 近十多年来,时滞微分方程的振动理论得到了迅速发展,但大部分是针对滞后型的。对中立型情况的研究结果还比较少,其中变系数方程的结果则更少。关于中立型方程解的振动性研究,不仅具有理论上的意义,从应用的观点来看也是十分重要的。例如,可以参看文献[3]和[6]。 最近,阮炯,Grammatikopoulos,Grove和Ladas,及Ladas和Sficas分别研究了中立型时滞微分方程     

一阶中立型时滞微分方程的振动性

通过构造适当的变换及有效函数,研究了一阶中立型时滞微分方程[x(t)-c(t)x(t-r)]′+p(t)f(x(t-τ))+∑ni=1qi(t)}f(x(t-σi))=0的振动性,获得了此方程所有解振动的n族充分条件.     

中立型时滞微分方程的振动性

本文讨论一类一阶中立型时滞微分方程的振动性，建立了此类方程一切解振动的几族充分条件，作为其推论的结果改进了文［１］，［２］，［３］的相应定理。     

二阶非线性中立型时滞微分方程的振动性

考虑二阶非线性中立型时滞分方程[a(t)|(z(t) p(t)x(t-τ))‘|^a-1(x(t) p(t)x(t-τ))‘]‘ q(t)|x(t-σ）|^a-1x(t-σ)=0(*)本文获得了方程（*)所有解振动的充分条件,推广并改进了[1]的结果。     

中立型时滞双曲微分方程的振动性

考虑一类中立型时滞双曲微分方程,得到了该方程振动的一个充分条件。     

一阶中立型时滞差分方程的线性化振动性定理

本文考虑一类非线性中立型时滞差分方程,证明了在一定条件下,若与此方程相关的一个线性差分方程的每个解振动,则该非线性差分方程的每个解也振动。     

奇数阶中立型差分方程的线性化振动性定理

本文得到了奇数阶中立型差分方程的一个线性化振动性定理,是Ｇｙ氹ｒｉ和Ｌａｄａｓ在文［２］中所提公开问题的一个离散结果     

非线性偶阶中立型时滞偏微分方程的振动性

建立了一类非线性偶阶中立型时滞偏微分方程的若干新的振动准则,所得的结果推广和改进了文献中的一些振动结果。     

LINEARIZED OSCILLATIONS FOR ODD-ORDER NEUTRAL DELAY DIFFERENTIAL EQUATIONS WITH ASYMPTOTIC PERIODICCOEFFICIENTS

1IntroductionSince1987,thelinearizedoscillationtheoryofnonlineardelaydifferentialequations(DDEs)hasabsorbedmanymathematicians(see[1,2]),itisparalleltotheso-calledlinearizedstabilitytheory,andhasbecomeamainstudyofoscillationtheoryofDDEs.ByusingthenecessaryandsufficientconditionsfortheoscillationoflinearDDEswithconstantcoefficients,theliteraturesconcentratedtoprovethatcertainnonlinearDDEhasthesameoscillatorycharacterasanassociatedlinearizedDDEwithconstantcoefficients.However)whenthelineari…     

LINEARIZED OSCILLATIONS FOR NEUTRAL DIFFERENTIAL EQUATIONS

Consider the nonlinear neutral delay differential equationwhere P, Q ∈ C([t0,∞),R), τ > 0, δ > 0. We obtain a linearized oscillation result by an associate linear equation in the case when liminfP(t) = p0 ∈[-1,0).     

LINEARIZED OSCILLATION FOR ODD-ORDER NEUTRAL DIFFERENTIAL EQUATIONS

By an associate linear equation, we obtain a linearized oscillation result of certain odd-order nonlinear neutral delay differential equation. The result answers partially an open problem proposed by Gyori and Ladas.     

奇数阶中立型差分方程的线性化振动性

考虑奇数阶中立型差分方程△^m(xn-png(xn-k)) qnh(xn-1)=0,1,…，其中{Pn},{qn}是正实数列，h,g∈C(R,R），k,l是非负整数，m是奇数，证明了在一定的条件下该方程的振动性与其相对应的一个常系数线性差分方程的振动性等价，并给出了其应用。     

OSCILLATION THEOREMS FOR DELAY AND NEUTRAL DELAY DIFFERENTIAL EQUATIONS

Oscillation criteria for the delay differential equationx′(t)+p(t)x(t-т(t))=0,where p, т are non-negative real-valued continuous functions are investigated inthe case when the numbers k=integral from n=t-т(t) to t(p(s)ds),L=integral from n=t-т(t) to t(p(s)ds)satisfy 0≤k<1/e and 1/e≤L<1. The present result improves almost allresults of the literature concerning it. Furthermore, it is established that allsolutions of the odd-order neutral delay differential equation(x(t)-px(t-т))~(n)+Q(t)x(t-σ)=0,where 0≤p<1,т,σ∈(0,∞)and Q(t)≥0,are oscillatory ifintegral from n=t-σ to t ((t-s)~(n-1)Q(s)ds>(1/e)(1-p)(n-1))!.This result generalizes a theorem of Gopalsamy et. al (Czech. Math. J., 42(1992),313-323)and also extends a very well-known result of Ladas (ApplicableAnalysls, 9(1979),93-98).     

二阶拟线性中立型时滞微分方程的振动性

考虑二阶中立型时滞微分方程[a(t)|(x(t) p(t)x(t-τ)）′|^α-1(x(t) p(t)x(t-τ））′]′ f(t,x(t-σ））=0(E)其中α，τ，σ是非负常数，a(t),p(t)∈C([t0,∞），R），f(t,x)∈C(R,R)。建立了方程（E）的一些新的振动条件。     

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.     

MONOTONE ITERATIVE TECHNIQUE FOR NONLINEAR NEUTRAL DELAY DIFFERENTIAL EQUATIONS

1Introductiondescently,themonotoneiteratiyetechniqueissuccessfultoprovetheexistenceofextremalsolutionsofvariousnonlinearproblemforordinarydifferentialequations,delaydifferentialequations,integro-differentialequationsetc.,see[1--101.Inthispapertweshallconsidertheexistenceofextremalsolutionsoftheinitialvalueproblem(IVPforshort)fornonlinearneutraldelaydifferentialequationswherefEC[IOxRxRxR,R],CO=C[[--a,0],R],IO=[to,to T],to20,T>0,a<0,T<0,--a=adn{a,T},I=f--a,0]andforanyteIO,u(t s)ECO,sE…