Hub location

1) The Uncapacitated Multiple Allocation Hub Location Problem (UMAHLP).

In Cánovas et al. (2007), we give an exact algorithm for the UMAHLP. The nice property of these approach, based on a dual-ascent strategy, is that it does not rely on any external solver but it is self-contained: a heuristic embedded in a branch-and-bound framework. At the moment of the research, this algorithm was able to move the size of the largest solved instances from 50 nodes to 120 nodes.

The research material of this paper can be downloaded from here:

• Code (in C++): aftumahlp.cpp.
• Original files: CAB data, AP data.
• All the files used in the paper: umahlp.zip.

2) The p-Median Uncapacitated Multiple Allocation Hub Location Problem.

In García et al. (2012), we give an exact algorithmfor solving the UMAHLP in under a condition of p-median. We give a formulation with only two indices and, based on a radius formulation, developed an exact branch-and-cut method. We even manage to solve some instances with more than 100 nodes.

The research material of this paper can be downloaded from here:

• Code (in C++): zhubs.zip.
• Results of the compuational study (complete): final_study.zip.