A parallel subgradient algorithm for Lagrangean dual function of the p-median problem

نویسندگان

  • Saïd Hanafi
  • Claudio Sterle
  • Anton Ushakov
  • Igor Vasil'ev
چکیده

In this paper we address a parallel version of subgradient algorithm to maximize Lagrangean dual function for the p-median problem. The parallelization is performed according to the sceme master-slave and using the Message Passing Interface. Computational results for very large-scale instances are given, showing the efficacy of the designed algorithm.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Ergodic, primal convergence in dual subgradient schemes for convex programming

Lagrangean dualization and subgradient optimization techniques are frequently used within the field of computational optimization for finding approximate solutions to large, structured optimization problems. The dual subgradient scheme does not automatically produce primal feasible solutions; there is an abundance of techniques for computing such solutions (via penalty functions, tangential app...

متن کامل

Lagrangean/surrogate relaxation for generalized assignment problems

This work presents Lagrangean/surrogate relaxation to the problem of maximum pro®t assignment of n tasks to m agents (n > m), such that each task is assigned to only one agent subject to capacity constraints on the agents. The Lagrangean/surrogate relaxation combines usual Lagrangean and surrogate relaxations relaxing ®rst a set of constraints in the surrogate way. Then, the Lagrangean relaxati...

متن کامل

A column generation approach to capacitated p-median problems

The Capacitated p-median problem (CPMP) seeks to solve the optimal location of p facilities, considering distances and capacities for the service to be given by each median. In this paper we present a column generation approach to CPMP. The identified restricted master problem optimizes the covering of 1-median clusters satisfying the capacity constraints, and new columns are generated consider...

متن کامل

A hybrid Lagrangean heuristic with GRASP and path-relinking for set k-covering

The set multicovering or set k-covering problem is an extension of the classical set covering problem, in which each object is required to be covered at least k times. The problem finds applications in the design of communication networks and in computational biology. We describe a GRASP with pathrelinking heuristic for the set k-covering problem, as well as the template of a family of Lagrange...

متن کامل

An Application of Lagrangean Decomposition to the Scheduling of Hot Charged Rolling in Steel Production

-In this paper a Lagrangean decomposition technique for solving the scheduling problem for Hot Charged Rolling (HCR) in the continuous casting process which involves sequencing and grouping. This Lagrangian relaxation algorithm is proposed that incorporate two sets of constraints into the objective function after applying the variable splitting technique. The relaxed problem has a special struc...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Stud. Inform. Univ.

دوره 9  شماره 

صفحات  -

تاریخ انتشار 2011