Computational Optimization and Applications

, Volume 35, Issue 2, pp 239–260 | Cite as

Solving the p-Median Problem with a Semi-Lagrangian Relaxation

  • C. BeltranEmail author
  • C. Tadonki
  • J. Ph. Vial


Lagrangian relaxation is commonly used in combinatorial optimization to generate lower bounds for a minimization problem. We study a modified Lagrangian relaxation which generates an optimal integer solution. We call it semi-Lagrangian relaxation and illustrate its practical value by solving large-scale instances of the p-median problem.


Lagrangian relaxation combinatorial optimization p-median problem 


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© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  1. 1.Logilab, HECUniversity of GenevaSwitzerland
  2. 2.Centre Universitaire InformatiqueUniversity of GenevaSwitzerland

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