【摘要】 如果u是半线性抛物型方程u₁=Δu+f（u）的解,则函数P=φ（|u|²）+z（t）F（u）满足一个抛物型微分不等式,从而关于它成立极值原理。更多还原

【Abstract】 Under appropriate assumptions on the functions z(t),φ(s) and F(u), the functional P(x,t)=φ(|u|~2)+z(t)F(u) satisfies a parabolic maximum principle if u is a solution of the semi-linear parabolic equation u_t=△u+f(u) and f(u) is such that f′(u)≤0.更多还原