@techreport{TR-IC-00-04,
  number = {IC-00-04},
  author = {Tallys H. Yunes and Arnaldo V. Moura and Cid C. Souza},
  title = {Modeling and Solving a Crew Rostering Problem with Constraint Logic Programming},
  month = {March},
  year = {2000}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 15 pages.
    \par\selectlanguage{english}\textbf{Abstract}
      This article describes the crew rostering problem stemming from
      the operation of a Brazilian bus company that serves a major
      urban area in the city of Belo Horizonte. The problem is solved
      by means of Integer Programming (IP) and Constraint Logic
      Programming (CLP) approaches, whose models are discussed in
      detail. Lower bounds obtained with a Linear Programming
      relaxation of the problem are used in order to evaluate the
      quality of the solutions found. We also present a hybrid column
      generation approach for the problem, combining IP and CLP over a
      set partitioning formulation. Experiments are conducted upon
      real data sets and computational results are evaluated,
      comparing the performance of these three solution methods.
  }
}