in Applied Mathematics, all three of them from the Universite Chouaib Doukkali , El Jadida, Morocco, in 1997 and 1999, respectivelly. Then I received the DEA and the doctoral degree, both in applied sciences and from the Ecole Polytechnique de Louvain , Universite Catholic de Louvain , Louvain-La-Neuve, Belgium, in 2001