Before revision:  Then, the approach with a hierarchical ADMM that contains outer loop iteration by the augmented Lagrangian method (ALM) , and inner loop iteration by three-block semi-proximal ADMM, is utilized to solve the resulting relaxed nonconvex optimization problem.
After revision:  Then, a hierarchical ADMM that contains outer loop iteration by the augmented Lagrangian method (ALM) , and inner loop iteration by three-block semi-proximal ADMM, is utilized to solve the resulting relaxed nonconvex optimization problem.