Constraint programming (CP) based column generation uses CP to solve the pricing subproblem. We consider a set partitioning formulation with a huge number of variables, each of which can be generated by solving a CP subproblem. We propose two customized search strategies to solve the CP subproblem, which aim to improve the coordination between the master problem and the subproblem. Specifically...

This article presents a column generation algorithm to calculate new improved lower bounds to the solution of maximal covering location problems formulated as a p-median problem. This reformulation leads to instances that are difficult for column generation methods. The traditional column generation method is compared with the new approach, where the reduced cost criterion used at the column se...

In this paper, we address a new integration of column generation and Lagrangian relaxation for solving flowshop scheduling problems to minimize the total weighted tardiness. In the proposed method, the initial columns are generated by using near-optimal dual variables for linear programming relaxation of Dantzig-Wolfe decomposition derived by the Lagrangian relaxation method. The column generat...

We study resource allocation in cellular systems and consider the problem of finding a power efficient scheduling in an uplink single carrier frequency division multiple access system (SC-FDMA). Due to the discrete nature of this problem and its computational difficulty, particularly in a real-time setting, the use of suboptimal algorithms is common practice. We aim at an effective way of gaugi...

This paper presents a column generation-based heuristics for the Vehicle Routing and scheduling Problem with Soft Time Windows (VRPSTW). The subproblem has been solved using a modified stochastic push forward insertion heuristics that incorporates the early and late arrival penalties. The useful dual information (shadow prices) from the column generation master problem guides the heuristic subp...

In this work we present a way of accelerating a column generation algorithm for the linear minimum cost multicommodity flow problem. We use a new model that, besides the usual variables corresponding to flows on paths, has a polynomial number of extra variables, corresponding to flows on circuits. Those extra variables are explicitly considered in the restricted master problem, from the beginni...