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8 Cologne-Twente Workshop on Graphs and Combinatorial Optimization CTW09 Proceedings of the Conference 8th Cologne-Twente Workshop on Graphs and Combinatorial Optimization CTW09 Ecole´ Polytechnique and CNAM Paris, France, June 2-4, 2009 Proceedings of the Conference Sonia Cafieri, Antonio Mucherino, Giacomo Nannicini, Fabien Tarissan, Leo Liberti (Eds.) 8th Cologne-Twente Workshop on Graphs and Combinatorial Optimization (CTW09) Ecole´ Polytechnique and CNAM Paris, France, June 2-4, 2009 The Cologne-Twente Workshop (CTW) on Graphs and Combinatorial Opti- mization started off as a series of workshops organized bi-annually by either K¨oln University or Twente University. As its importance grew over time, it re-centered its geographical focus by including northern Italy (CTW04 in Menaggio, on the lake Como and CTW08 in Gargnano, on the Garda lake). This year, CTW (in its eighth edition) will be staged in France for the first time: more precisely in the heart of Paris, at the Conservatoire National d’Arts et M´etiers (CNAM), between 2nd and 4th June 2009, by a mixed organizing committee with members from LIX, Ecole´ Polytechnique and CEDRIC, CNAM. As tradition warrants, a special issue of Discrete Applied Mathematics (DAM) will be devoted to CTW09, containing full-length versions of selected presentations given at the workshop and possibly other contributions related to the workshop topics. The deadline for submission to this issue will be posted in due time on the CTW09 website http://www.lix.polytechnique.fr/ctw09. The Proceedings Editors wish to thank the members of the Program Commit- tee: U. Faigle (Universit¨at zu K¨oln), J. Hurink (Universiteit Twente), L. Liberti (Ecole´ Polytechnique), F. Maffioli (Politecnico di Milano), G. Righini (Universit`a degli Studi di Milano), R. Schrader (Universit¨at zu K¨oln), R. Schultz (Universit¨at Duisburg-Essen), for setting up such an attractive program. Special thanks also go to the anonymous referees. This conference was partially sponsored by: the Digiteo (www.digiteo.fr) foundation, CNRS, and the Thales Chair at LIX. Editors: SONIA CAFIERI ANTONIO MUCHERINO GIACOMO NANNICINI FABIEN TARISSAN LEO LIBERTI LIX, Ecole´ Polytechnique Paris, May 2009 Organization The CTW09 conference is co-organized by the Laboratoire d’Informatique (LIX) at Ecole´ Polytechnique and by the Centre d’Etude et Recherche en Informa- tique du CNAM (CEDRIC) at the Conservatoire National d’Arts et Mtiers (CNAM). Scientific Committee U. Faigle (Universit¨at zu Koln) • J.L. Hurink (Universiteit Twente) • L. Liberti (Ecole´ Polytechnique, Paris) • F. Maffioli (Politecnico di Milano) • G. Righini (Universit`adegli Studi di Milano) • R. Schrader (Universit¨at zu Koln) • R. Schultz (Universit¨at Duisburg-Essen) • Organizing Committee S. Cafieri (LIX, Ecole´ Polytechnique) • M.-C. Costa (CEDRIC, CNAM) • C. D¨urr (LIX, Ecole´ Polytechnique) • L. Liberti (Chair – LIX, Ecole´ Polytechnique) • A. Mucherino (LIX, Ecole´ Polytechnique) • G. Nannicini (LIX, Ecole´ Polytechnique) • C. Picouleau (CEDRIC, CNAM) • M.-C. Plateau (GdF) • J. Printz (CMSL, CNAM) • E. Rayssac (LIX, Ecole´ Polytechnique) • F. Tarissan (LIX, Ecole´ Polytechnique) • Table of Contents Traveling Salesman Problem Lecture Hall A, Tue 2, 08:45–10:15 C. Dong, C. Ernst, G. Jaeger,¨ D. Richter, P. Molitor Effective Heuristics for Large Euclidean TSP Instances Based on Pseudo Backbones 3 M. Casazza, A. Ceselli, M. Nunkesser Efficient Algorithms for the Double Traveling Salesman ProblemwithMultipleStacks 7 M. Bruglieri, A. Colorni, A. Lue The Parking Warden Tour Problem 11 Graph Theory I Lecture Hall B, Tue 2, 08:45–10:15 I. Sau, D. Thilikos OnSelf-DualityofBranchwidtinGraphsofBoundedGenus 19 S. Nikolopoulos, C. Papadopoulos A Simple Linear-Time Recognition Algorithm for Weakly Quasi-ThresholdGraphs 23 H. Gropp From Sainte-Lagu¨eto Claude Berge — French Graph Theory in theTwentiethCentury 28 Combinatorial Optimization Lecture Hall A, Tue 2, 10:30–12:30 J. Maßberg, T. Nieberg Colored Independent Sets 35 V. Lozin A Note on the Parameterized Complexity of the Maximum Independent Set Problem 40 G. Nicosia, A. Pacifici, U. Pferschy On Multi-Agent Knapsack Problems 44 L. Simonetti, Y. Frota, C. Souza An Exact Method for the Minimum Caterpillar Spanning Problem 48 Coloring I Lecture Hall B, Tue 2, 10:30–12:30 R. Machado, C. de Figueiredo NP-Completeness of Determining the Total Chromatic Number of Graphs that do not Contain a Cycle with a Unique Chord 55 R. Kang, T. Muller¨ Acyclic and Frugal Colourings of Graphs 60 P. Petrosyan, H. Sargsyan On Resistance of Graphs 64 E. Bampas, A. Pagourtzis, G. Pierrakos, V. Syrgkanis Colored Resource Allocation Games 68 Cutting and Packing Lecture Hall A, Tue 2, 14:00–15:30 C. Arbib, F. Marinelli, C. Scoppola A Lower Bound for the Cutting Stock Problem with a Limited Number of Open Stacks 75 H. Fernau, D. Raible Packing Paths: Recycling Saves Time 79 J. Schneider, J. Maßberg Rectangle Packing with Additional Restrictions 84 Paths Lecture Hall B, Tue 2, 14:00–15:30 F. Usberti, P. Franc¸a, A. Franc¸a The Open Capacitated Arc Routing Problem 89 M. Maischberger OptimisingNodeCoordinatesfortheShortestPathProblem 93 R. Bhandari The Sliding Shortest Path Algorithms 97 Quadratic Programming Lecture Hall A, Tue 2, 15:45–16:45 W. Ben-Ameur, J. Neto A Polynomial-Time Recursive Algorithm for some Unconstrained Quadratic Optimization Problems 105 I. Schuele, H. Ewe, K.-H. Kuefer Finding Tight RLT Formulations for Quadratic Semi-AssignmentProblems 109 Trees Lecture Hall B, Tue 2, 15:45–16:45 V. Borozan, R. Muthu, Y. Manoussakis, C. Martinhon, A. Abouelaoualim, R. Saad Colored Trees in Edge-Colored Graphs 115 K. Cameron, J. Fawcett Intermediate Trees 120 Plenary Session I Lecture Hall A, Tue 2, 16:45–17:30 A. Lodi Bilevel Programming and Maximally Violated Valid Inequalities 125 Integer Programming Lecture Hall A, Wed 3, 08:45–10:15 R. Schultz Decomposition Methods for Stochastic Integer Programs with Dominance Constraints 137 S. Kosuch, A. Lisser On a Two-Stage Stochastic Knapsack Problem with ProbabilisticConstraint 140 G. Cornuejols,´ L. Liberti, G. Nannicini Improved Strategies for Branching on General Disjunctions 144 Graph Theory II Lecture Hall B, Wed 3, 08:45–10:15 G. Katona, I. Horvath´ Extremal Stable Graphs 149 V.A. Leoni, M.P. Dobson, Gr. Nasini Recognizing Edge-Perfect Graphs: some Polynomial Instances 153 M. Freitas, N. Abreu, R. Del-Vecchio Some Infinite Families of Q-Integral Graphs 157 Applications Lecture Hall A, Wed 3, 10:30–12:30 A. Ceselli, R. Cordone, M. Cremonini Balanced Clustering for Efficient Detection of Scientific Plagiarism 163 V. Cacchiani, A. Caprara, M. Fischetti Robustness in Train Timetabling 171 F. Roda, L. Liberti, F. Raimondi CombinatorialOptimizationBasedRecommenderSystems 175 G. Righini, R. Cordone, F. Ficarelli Bounds and Solutions for Strategic, Tactical and OperationalAmbulanceLocation 180 Coloring II Lecture Hall B, Wed 3, 10:30–12:30 E. Hoshino, C. de Souza, Y. Frota A Branch-and-Price Approach for the Partition Coloring Problem 187 M. Soto, A. Rossi, M. Sevaux Two Upper Bounds on the Chromatic Number 191 F. Bonomo, G.A. Duran,´ J. Marenco, M. Valencia-Pabon MinimumSumSetColoringonsomeSubclassesofBlockGraphs 195 A. Lyons Acyclic and Star Colorings of Joins of Graphs and an AlgorithmforCographs 199 Exact Algorithms Lecture Hall A, Wed 3, 14:00–15:30 H. Fernau, S. Gaspers, D. Kratsch, M. Liedloff, D. Raible Exact Exponential-Time Algorithms for Finding Bicliques inaGraph 205 L. Bianco, M. Caramia An Exact Algorithm to Minimize the Makespan in Project Scheduling with Scarce Resources and Feeding Precedence Relations 210 R. Macedo, C. Alves, V. de Carvalho Exact Algorithms for Vehicle Routing Problems with DifferentServiceConstraints 215 Networks I Lecture Hall B, Wed 3, 14:00–15:30 D. Lozovanu, S. Pickl Algorithmic Solutions of Discrete Control Problems on StochasticNetworks 221 L. Belgacem, I. Charon, O. Hudry Routing and Wavelength Assignment in Optical Networks by Independent Sets in Conflict Graphs 225 A. Guedes, L. Markenzon, L. Faria Recognition of Reducible Flow Hypergraphs 229 Complexity Lecture Hall A, Wed 3, 15:45–16:45 A. Scozzari, F. Tardella On the Complexity of Graph-Based Bounds for the Probability BoundingProblem 235 B. Engels, S. Krumke, R. Schrader, C. Zeck Integer Flow with Multipliers: The Special Case of Multipliers1and2 239 Polyhedra Lecture Hall B, Wed 3, 15:45–16:45 R. Stephan Classification of 0/1-Facets of the Hop Constrained Path Polytope Defined on an Acyclic Digraph 247 A. Galluccio, C. Gentile, M. Macina, P. Ventura The k-GearCompositionandtheStableSetPolytope 251 Plenary Session II Lecture Hall A, Wed 3, 16:45–17:30 M. Habib DiameterandCenterComputationsinNetworks 257 Polynomial-time Algorithms Lecture Hall A, Thu 4, 08:45–10:15 M. Bodirsky, G. Nordh, T. von Oertzen Integer Programming with 2-Variable Equations and 1-VariableInequalities 261 D. Muller¨ FasterMin-MaxResourceSharingandApplications 265 A. Bettinelli, L. Liberti, F. Raimondi, D. Savourey The Anonymous Subgraph Problem 269 Graph Theory III Lecture Hall B, Thu 4, 08:45–10:15 A. Rafael, F.-T. Desamparados, J.A. Vilches TheNumberofExcellentDiscreteMorseFunctionsonGraphs 277 F. Bonomo, G.A. Duran,´ L.N. Grippo, M.D. Safe Partial Characterizations of Circle Graphs 281 T. Shigezumi, Y. Uno, O. Watanabe A Replacement Model for a Scale-Free Property of Cliques 285 Graph Theory IV Lecture Hall A, Thu 4, 10:30–12:30 A. Darmann, U. Pferschy, J. Schauer, G. Woeginger CombinatorialOptimizationProblemswithConflictGraphs 293 J.M. Sigarreta, I. Gonzlez Yero, S. Bermudo, J.A. Rodr´ıguez-Velazquez´ On the Decomposition of Graphs into Offensive k-Alliances 297 M. Brinkmeier 2 ( ) Increasing the Edge Connectivity by One in (λ n log ∗ n) ExpectedTime 301 O G V. Giakoumakis, O. El Mounir Enumerating all Finite Sets of Minimal Prime Extensions of Graphs 305 Networks II Lecture Hall B, Thu 4, 10:30–12:30 C. Bentz On Planar and Directed Multicuts with few Source-Sink Pairs 313 F. Usberti, J. Gonzlez, C.L. Filho, C. Cavellucci Maintenance Resources Allocation on Power Distribution Networks with a Multi-Objective Framework 317 E. Grande, P.B. Mirchandani, A. Pacifici Column Generation for the Multicommodity Min-cost Flow OverTimeProblem 321 F.
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