Oscillations of higher order nonlinear functional differential equations with impulses

https://doi.org/10.1016/j.amc.2007.01.029Get rights and content

Abstract

The present paper is devoted to the investigation of the oscillation of a kind of very extensively higher order nonlinear functional differential equations with impulses, some interesting results are obtained. The results extend and improve the earlier publications. Two examples are given to illustrate the theory.

Introduction

The oscillations of classical second order nonlinear (linear) ODE (FDE) has been extensively studied in the literature, e.g., Refs. [1], [2], [3], [4], [5], [6], [7], [8], [9], [10].

However, impulsive effect likewise exists in a wide variety of evolutionary processes in which states are changed abruptly at certain moments of time, involving such field as medicine and biology, economics, mechanics, electronics, and telecommunications, etc. Many interesting results on impulsive effect have been gained in [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23]. Those papers have only first or second order ODE (FDE) with impulses. But papers devoted to the study of the oscillations of differential equation of higher order with impulses are quite rare.

Papers devoted to the study of the oscillations of higher order nonlinear ODE with impulses has been done in [24]. But it is not considered with delay effect and the main difficulty for higher order FDE comes from every order differential coefficient relation. Therefore, it is necessary to consider both impulsive effect and delay effect on the oscillations of differential equation.

In the paper, we mainly study a kind of very extensively higher order nonlinear FDE with impulses under the conditions (A), (B), (C). We can always find some suitable impulse functions such that all the solutions of the equation can become oscillatory under the impulse control. The results extend and improve the earlier publications. Two example are given to illustrate the theory.

Section snippets

Main results

We consider the following systems:[r(t)|x(2n-1)(t)|α-1x(2n-1)(t)]+f(t,x(t),x(t-τ))=0,tt0,ttk,x(i)(tk+)=gk(i)(x(i)(tk)),i=0,1,,2n-1,k=1,2,x(i)(t0+)=x0(i),x(t)=ϕ(t),t0-τtt0,wherex(i)(t)=limh0-x(i-1)(t+h)-x(i-1)(t)h,x(i)(t+)=limh0+x(i-1)(t+h)-x(i-1)(t)h.ϕ:[t0-τ,t0]R has at most finite discontinuous points of the first kind and is left continuous at these points. α>0,τ>0,0<t0<t1<t2<<tk<,k=1,2,,limktk=+,x(0)(t)=x(t), n is a natural number. Here, we always assume that the following

Example

Example 1

Considerx(2n)(t)+14tx3(t-12)=0,t12,tk,k=1,2,x(k+)=x(k),x(i)(k+)=kk+1x(i)(k),i=1,,2n-1.x(12)=x0,x(i)(12)=x0(i),x(t)=ϕ(t),t[12,1]where ak(0)=bk(0)=1,ak(i)=bk(i)=kk+1,i=1,2,,2n-1,p(t)=14t,tk=k,φ(x)=x3,r(t)=1,α=1,t0=12. It is obvious that the condition (A), (B) are satisfied, for condition (C) when i>1,ak(i)=bk(i-1)=kk+1(t1-t0)+(t2-t1)+(t3-t2)++(tm+1-tm)+=12+1++1+=+.When i=1,ak(1)=kk+1,bk(0)=1(t1-t0)+12(t2-t1)+13(t3-t2)++1m+1(tm+1-tm)+=12+12+13++1m+1+=+.From the above,the condition

References (26)

  • I.V. Kamenev

    A criterion for the oscillation of solutions of second order ordinary differential equations

    Mat. Zametki

    (1970)
  • I.V. Kamenev

    Some specifically nonlinear oscillation theorem

    Mat. Zametki

    (1971)
  • C.C. Travis

    A note on second order nonlinear oscillation

    Math. Japan.

    (1973)
  • Cited by (4)

    Foundation item: This work was partially supported by Natural Science Foundation of Guangdong (011471) and Natural Science Foundation of Guangdong Higher Education (0120), Science and Technology Plan Project of Guangzhou (2006J1-C0341).

    View full text