Advances in Difference Equations
Volume 2008 (2008), Article ID 816091, 11 pages
doi:10.1155/2008/816091

Almost-periodic weak solutions of second-order neutral delay-differential equations with piecewise constant argument

Li Wang and Chuanyi Zhang

Department of Mathematics, Harbin Institute of Technology, Harbin 150001, China

Abstract

We investigate the existence of almost-periodic weak solutions of second-order neutral delay-differential equations with piecewise constant argument of the form (x(t)+x(t1))′′=qx(2[(t+1)/2])+f(t), where [] denotes the greatest integer function, q is a real nonzero constant, and f(t) is almost periodic.