A strong maximum principle for differential equations with nonstandard p(x)-growth conditions

In this paper, with some special technics, we give a strong maximum principle for the equations with nonstandard p(x)-growth conditions−div(φ(x,|∇u|)∇u)+d(x)f(x,u)=0in Ω, where φ(x,s), d(x), f(x,u) satisfy some conditions.