摘要

In this article we study the weak solutions of elliptic equation -Delta u = 2 partial derivative delta 0/partial derivative nu in Omega, u = 0 on partial derivative Omega where Omega is an open bounded C-2 domain of R-N with N >= 2 containing the origin, v is a unit vector and (partial derivative delta 0)(partial derivative nu) is defined in the distribution sense, i.e. = partial derivative zeta(0)/partial derivative nu, for all zeta is an element of C-0(1)(Omega). We prove that this problem admits a unique weak solution u in the sense that integral(Omega)u(-Delta)xi dx = 2 partial derivative xi(0)/partial derivative nu, for all xi is an element of C-0(2)(Omega). Moreover, u has an anisotropic singularity and can be approximated, as t -> 0(+), by the solutions of -Delta u = delta 1t nu - delta t nu/t in Omega, u = 0 on partial derivative Omega.