In this paper, we suggest and
analyze a new alternating direction scheme for the separable constrained
convex programming problem. The theme of this paper is twofold. First, we
consider the square-quadratic proximal (SQP) method. Next, by combining the
alternating direction method with SQP method, we propose a descent SQP
alternating direction method by using the same descent direction as in [6]
with a new step size ?k. Under appropriate conditions, the global
convergence of the proposed method is proved. We show the O(1/t) convergence
rate for the SQP alternating direction method. Some preliminary
computational results are given to illustrate the efficiency of the proposed
method.