OSCILLATION OF FIRST ORDER NONLINEAR IMPULSIVE DIFFERENTIAL EQUATIONS WITH MIXED ARGUMENT

This paper devotes to study the oscillatory behavior of solutions of a first order nonlinear impulsive differential equation with mixed argument. First, without assuming the deviating argument to be retarded or advanced, a sufficient condition is established for all solutions of the differential equation to be oscillatory. Next, a sufficient condition for the differential equation to have nonoscillatoty solution is given. Finally, a sufficient and necessary condition for all solutions of the differential equation to be oscillatory is obtained.     

ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATION

In this paper, a class of higher order linear differential equation is investigated. The order and the hyper-order of the solutions of the equation are exactly estimated under some certain conditions.     

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。     

一类二阶非线性微分系统解的有界性

研究了如下一类二阶非线性微分系统解的有界性.得到了(E)的所有解有界的新的充分条件和充分必要条件.所获结果能够应用于Lienard类型方程它改进与扩展了[1-5]等文献中的相应结果.     

一类非线性系统解的有界性

研究了一类非线性微分系统解的有界性 ,所获结果可应用于Li啨ｎａｒｄ类型的方程 ,改进与扩展了众多已有文献中的结果     

不稳定型二阶中立型方程正解的存在性与有界振动

本文研究一类不稳定型二阶中立型微分方程正解的存在性与有界振动．证明了在一定条件下不稳定型二阶中立型方程总存在无界正解，并给出了保证其方程的一切有界解都振动的充分条件，改进了文［１，２］中的有关条件．     

二阶延迟微分方程θ-方法的TH-稳定性

This paper is concerned with the TH-stability of second order delay differential equation. A sufficient condition such that the system is asymptotically stable is derived. Furthermore, a sufficient condition is obtained for the hnear θ-method to be TH-stable. Finally, the plot of stability region for the particular case is presented.     

四阶非线性微分方程周期解的存在性

应用构造Ｌｉａｐｕｎｏｖ函数的方法，给出了四阶非线性微分方程存在周期解的一组充分条件．     

Oscillation criteria for even order differential equations

Summary Three theorems concerning oscillatory properties of solutions of even order ordinary differential equations are given. One theorem gives sufficient conditions for all solutions of (*) y⁽²ⁿ⁾(x) + f(y(x))p(x) = 0 to possess an infinite number of zeroes on the positive x axis. Another theorem gives sufficient conditions for all solutions of the general homogeneous linear equation of order 2n to have the same oscillatory property. Finally a necessary condition is given for (*) to have a solution with a last zero. This research was carried out under the support of Grant NSF GP-2067 with the National Science Foundation.     

特殊形式的倒向随机微分方程在金融市场中的应用

首先,针对一类线性倒向随机微分方程,给出了g-鞅同鞅之间相互联系所满足的充分条件.通过该条件得到了经典的Black-Scholes模型下未定权益的公平价格过程以及最优增长投资策略的价格过程.其次,引入了带惩罚的非线性倒向随机微分方程,并通过惩罚比率的不同取值来讨论相关的经济学意义.     

二阶微分方程非振动的必要与充分条件

本文证明了一个微分恒等式，得到了二阶非线性微分方程非振动的一个充要条件，研究了一类二阶微分方程的振动性质，推广了现有的结果。     

ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATIONS

In this paper, authors investigate the order of growth and the hyper order of solutions of a class of the higher order linear differential equation, and improve results of M. Ozawa^[6], G. Gundersen^[7] and J.K. Langley^[8], Li Chun-hong^[11].     

Ascoli-Arzela定理的一个推广及应用

给出了无穷区间上一类抽象连续函数族相对紧性判断的一个充分必要条件，并应用它获得了抽象空间上一阶微分方程的终值问题和Ｆｒｅｄｈｏｌｍ型积分方程解的存在性。     

高阶中立型时滞差分方程解的振动性

研究了一类具有变系数的高阶中立型时滞差分方程解的振动性，给出了其有界解振动的两个充分条件。     

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.     

具有时滞的利率-流通量方程的建立及其应用

本文对金融网络建立了带有时滞的利率-流通量方程，应用时滞微分方程理论，我们得到金融网络中，各节点利率最终将稳定于其基本利率的充分必要条件；给出了各节点利率均振动的充分必要条件以及存在周期解的充分必要条件。     

On the dominance of roots of characteristic equations for neutral functional differential equations

We present a sufficient condition for a zero of a function that arises typically as the characteristic equation of a linear functional differential equations of neutral type, to be simple and dominant. This knowledge is useful in order to derive the asymptotic behaviour of solutions of such equations. A simple characteristic equation, arisen from the study of delay equations with small delay, is analyzed in greater detail.     

中立型泛函微分方程周期解问题

利用Fourier级数理论研究了一类k-阶线性中立型泛函微分方程周期解问题,给出了周期解存在唯一性的充要条件。利用此结果并结合Schauder不动点原理,进一步研究了一类k-阶非线性中立型泛函微分方程,得到了存在周期解的新的结果。这些结果改进和推广了近期文献中的已有结论。     

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.     

关于—类三阶混合型方程和变系数双曲型方程的边值问题

本文先扼要介绍一类三阶双曲抛物混合型偏微分方程的边值问题，然后讨论了与之有关的一类变系数三阶双曲型方程以特征线为支柱的边值问题，得到了有唯一解时此变系数应满足的充分必要条件。