Oscillation of the solutions of parabolic differential equations of neutral type

摘要

Sufficient conditions are obtained for the oscillation of the solutions of linear parabolic differential equations of neutral type of the form ∂∂t[u - Σi=1mλi(t)u(x,t-τi]=a(t)▵u+Σi=1sai(ft)▵u(x,t-pi)-p(x,t)u-Σi=1kpi(x,t)u(x,t-σi), (x,t)ϵΩ×(0,∞), where Ω is a bounded domain in Rn with a piecewise smooth boundary.