المنشورات و المؤلفات

We study the behavior at infinity in time of any global solution θ in C (R , H^{ 2−2α} R^2) of the surface quasigeostrophic equation with subcritical exponent 2/3 ≤ α ≤ 1. We prove that the limit of θ is 0 in the space H^{ 2−2α} R^2. Moreover, we...
This paper gives a solution, without the use of the three-term recurrence relation, of the problem posed in Ismail (Classical and Quantum Orthogonal Poly- nomials in One Variable, Cambridge University Press, Cambridge, 2005) (Problem 24.8.2, p. 658...
In this work, we give a unification and generalization of Laguerre and Hermite polynomials for which the orthogonal property is replaced by the d-orthogonality. We state some properties of these new polyno- mials.    
In this Note, we prove that all the components of a d-symmetric classical d-orthogonal are classical and in the case where the sequence is m-symmetric and d-orthogonal, we prove that the first component of an m-symmetric classical d-orthogonal is...
We study the regularity of the solutions of the surface quasi-geostrophic equation with subcritical exponent 1/2 < α ≤ 1. We prove that if the initial data is small enough in the critical space Ḣ_{ 2−2α} (R^2 ), then the regularity of the...
Let M be the group of Mobius transformations on the extented plane and f_M={f^n, n in Z} the cyclic subgroup of M generated by f , for f in M. If  f_M   is finite of order n, f is called an n-cycle. We prove in the first part that if f is an n-cycle...