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10th Cologne-Twente Workshop on Graphs and Combinatorial Optimization CTW 2011 Villa Mondragone, Frascati, June 14-16, 2011 Proceedings of the Conference Ludovica Adacher, Marta Flamini, Gianmaria Leo, Gaia Nicosia, Andrea Pacifici, Veronica Piccialli (Eds.) 10th Cologne-Twente Workshop on Graphs and Combinatorial Optimization (CTW 2011) Villa Mondragone, Frascati, June 14-16, 2011 The Cologne-Twente Workshop (CTW) on Graphs and Combinatorial Optimiza- tion started off as a series of workshops on theory and applications of discrete algo- rithms, graphs and combinatorial structures in the wide sense, organized by either Koln¨ University or Twente University. The first nine editions of CTW have been held in Cologne (2001, 2005, and 2010); Enschede (2003 and 2007); Menaggio (2004); Lambrecht (2006); Gargnano (2008) and Paris (2009). The 10th edition of the workshop will be hosted by Universita` di Roma “Tor Vergata”, in Villa Mondragone, an historical villa located in Frascati (Rome), Italy, from June 14 to 16, 2011. As in previous editions, a special issue of Discrete Applied Mathematics (DAM) will be devoted to CTW 2011, containing full-length versions of selected presen- tations given at the workshop and possibly other contributions related to the work- shop topics. CTW 2011 will honor the memory of Prof. Bruno Simeone (Universita` degli Studi di Roma “La Sapienza”) who recently passed away. We are grateful to Bruno’s friends and colleagues who are commemorating his fundamental contributions in the field of combinatorial optimization and graph theory of the last four decades. We wish to thank the members of the Program Committee: U. Faigle (Universitat¨ zu Koln),¨ J. Hurink (Universiteit Twente), L. Liberti (Ecole´ Polytechnique), F. Maffioli (Politecnico di Milano), G. Righini (Universita` degli Studi di Milano), R. Schrader (Universitat¨ zu Koln),¨ R. Schultz (Universitat¨ Duisburg-Essen), for setting up such an attractive program. Special thanks also go to some volunteering referees. LUDOVICA ADACHER, MARTA FLAMINI, GIANMARIA LEO, GAIA NICOSIA, ANDREA PACIFICI, VERONICA PICCIALLI Universita` di Roma “Tor Vergata” e “Roma Tre”, Roma, Italy, June 6, 2011 Organization The CTW 2011 conference is co-organized by the Universita` di Roma “Tor Ver- gata” and Universita` “Roma Tre”. The conference is hosted by Villa Mondragone in Frascati, thanks to a sponsorship of Universita` di Roma “Tor Vergata”. We are also grateful to Microsoft for their partial support the workshop. Scientific Committee Ulrich Faigle (U. Cologne), • Johann L. Hurink (U. Twente), • Leo Liberti (Ecole´ Polytechnique, Paris) • Francesco Maffioli (Politecnico, Milano), • Gaia Nicosia (U. Roma Tre), • Andrea Pacifici (U. Roma Tor Vergata), • Giovanni Righini (U. Milano), • Rainer Schrader (U. Cologne), • Rudiger Schultz (U. Duisburg-Essen) • Organizing Committee Ludovica Adacher (U. Roma Tre), • Marta Flamini (U. Uninettuno), • Gianmaria Leo (U. Roma Tor Vergata), • Gaia Nicosia (U. Roma Tre), • Andrea Pacifici (U. Roma Tor Vergata), • Veronica Piccialli (U. Roma Tor Vergata) • Table of contents Memorial Session Talks Becker R. Research work with Bruno Simeone 1 Crama Y. Control and voting power in complex shareholding networks 4 Hansen P. Bruno Simeone’s Work in Clustering 8 Golumbic M. Graph sandwich problems 10 Boros E. Incompatibility graphs and data mining 11 Serafini P. Separating negative and positive points with the minimum number of boxes 12 Contributed Abstracts Abrardo A, M. Belleschi and P. Detti Resources and transmission formats allocation in OFDMA networks 19 Adacher L. and M. Flamini Modeling and solving aircrafts scheduling problem in ground control 23 Addis B., G. Carello and F. Malucelli Network design with SRG based protection 27 Agnetis A., P. Detti, M. Pranzo and P. Martineau Scheduling problems with unreliable jobs and machines 32 Alba M., F. Clautiaux, M. Dell’Amico and M. Iori Models and Algorithms for the Bin Packing Problem with Fragile Objects 36 Albano A. and A. Do Lago New upper bound for the number of maximal bicliques of a bipartite graph 40 Albrecht K. and U. Faigle Binary Betting Strategies with Optimal Logarithmic Growth 44 Amaldi E., S. Coniglio and L. Taccari Formulations and heuristics for the k-Piecewise Affine Model Fitting problem 48 Amaldi E., C. Iuliano and R. Rizzi On cycle bases with limited edge overlap 52 Arbib C., G. Felici and M. Servilio Sorting Common Operations to Minimize Tardy Jobs 56 Argiroffo G. and A. Wagler Generalized row family inequalities for the set covering polyhedron 60 Bauer J. One Minimum-Cost Network Flow Problem to Identify a Graph’s Connected Components 64 Bermudo S. and H. Fernau Computing the differential of a graph 68 B´ına W. Enumeration of Labeled Split Graphs and Counts of Important Superclasses 72 Boehme T. and J. Schreyer Local Computation of Vertex Colorings 76 Bonomo F., G. Oriolo and C. Snels A primal algorithm for the minimum weight clique cover problem on a class of claw-free perfect graphs 80 Bonomo F. and J. L. Szwarcfiter Characterization of classical graph classes by weighted clique graphs 84 Bruglieri M., P. Cappanera and M. Nonato The gateway location problem for hazardous material transportation 88 Calamoneri T. and B. Sinaimeri Labeling of Oriented Planar Graphs 93 Cano R. G., G. Kunigami, C.C. De Souza and P. J. De Rezende Effective drawing of proportional symbol maps using GRASP 97 Carli M. and F. Pascucci Sensor Network Localization Using Compressed Extended Kalman Filter 101 Cello M., G. Gnecco, M. Marchese and M. Sanguineti A Generalized Stochastic Knapsack Problem with Application in Call Admission Control 105 Cerioli M.R., H. Nobrega and P. Viana A partial characterization by forbidden subgraphs of edge path graphs 109 Ceselli A., G. Righini and E. Tresoldi Combined Location and Routing Problems in Drug Distribution 113 Coniglio S. The impact of the norm on the k-Hyperplane Clustering problem: relaxations, restrictions, approximation factors, and exact formulations 118 Cordone R. and G. Lulli A Lagrangian Relaxation Approach for Gene Regulatory Networks 122 Costa A., P. Hansen and L. Liberti Bound constraints for Point Packing in a Square 126 Couturier J. F. and D. Kratsch Bicolored independent sets and bicliques 130 Cullenbine C. , K. Wood and A. Newman New Results for the Directed Network Diversion Problem 134 De Santis M., S. Lucidi and F. Rinaldi A New Feasibility Pump-Like Heuristic for Mixed Integer Problems 138 De Santis M., S. Lucidi and F. Rinaldi Continuous Reformulations for Zero-one Programming Problems 142 Dell’Olmo P., R. Cerulli and F. Carrabs The maximum labeled clique problem 146 Factorovich P., I. Mendez-D´ ´ıaz and P. Zabala The Pickup and Delivery Problem with Incompatibility Constraints 150 Faigle U. and A. Schoenhuth Representations of Power Series over Word Algebras 154 Gamst M. and N. Kjeldsen N. The Boat and Barge Problem 158 Gaudilliere A., A. Iovanella, B. Scoppola, E. Scoppola and M. Viale A Probabilistic Cellular Automata algorithm for the clique problem 162 Golovach P., M. Kaminski and D. Thilikos Odd cyclic surface separators in planar graphs 165 Hossain S. Computing Derivatives via Compression : An Exact Scheme 168 Kern W. and X. Qiu Improved Taxation Rate for Bin Packing Games 173 Kochol M. Decomposition of Tutte Polynomial 177 Kosuch S. Approximability of the Two-Stage Knapsack problem with discretely distributed weights 180 Laurent M. and A. Varvitsiotis Computing the Grothendieck constant of some graph classes 184 Liberti L., B. Masson, C. Lavor and A. Mucherino Branch-and-Prune trees with bounded width 189 Lozovanu D. and S. Pickl Discounted Markov Decision Processes and Algorithms for Solving Stochastic Control Problem on Networks 194 Mendez-D´ ´ıaz I., J. J. Miranda Bront, P. Toth and P. Zabala Infeasible path formulations for the time-dependent TSP with time windows 198 Milanic M. A hereditary view on efficient domination 203 Monaci M. and U. Pferschy On the Robust Knapsack Problem 207 Mucherino A., I. Wohlers, G. Klau and R. Andonov Sparsifying Distance Matrices for Protein-Protein Structure Alignments 211 Narayanan N. Minimally 2-connected graphs and colouring problems 215 Nicoloso S. and U. Pietropaoli Bipartite finite Toeplitz graphs 219 Nobili P. and A. Sassano A reduction algorithm for the weighted stable set problem in claw-free graphs 223 Petrosyan P. and R. Kamalian Edge-chromatic sums of regular and bipartite graphs 227 Puerto J., F. Ricca and A. Scozzari Range minimization problems in path-facility location on trees 231 Roda F., P. Hansen and L. Liberti The price of equity in the Hazmat 235 Saputro S.W., R. Simanjuntak , S. Uttunggadewa, H. Assiyatun, E. Tri Baskoro, A.N.M Salman On graph of order-n with the metric dimension n 3 239 − Scheidweiler R. and E. Triesch Matchings in balanced hypergraphs 244 Sevastyanov S. and B. Lin Efficient enumeration of optimal and approximate solutions of a scheduling problem 248 Skupien´ Z. Majorization and the minimum number of dominating sets 252 Stephan R. Reducing the minimum T-cut problem to polynomial size linear programming 255 Torres L. and A. Wagler The dynamics of deterministic systems from a hypergraph theoretical point of view 259 Touati-Moungla N. and D. Brockhoff An Evolutionary Algorithm for the Multiobjective Risk-Equity Constrained Routing Problem 263 Van Zuylen A., F. Schalekamp and D. P. Williamson Popular Ranking 267 Vanhove S. and V. Fack Locally optimal dissimilar paths in road networks 271 Yasar Diner O. and D. Dyer Searching Circulant Graphs 275 Detailed Conference Program 279 Index of authors 289 Memorial Session Talks Research Work with Bruno Simeone Ronald I. Becker AIMS (African Institute for Mathematical Sciences),6-8 Melrose Road, Muizenberg 7945, South Africa Department of Mathematics and Applied Mathematics University of Cape Town, Rondebosch 7701, South Africa [email protected] Key words: Graph Partitioning, Continuous Partitioning, Tree Partitioning, Grid Graph partitioning, Optimization, Graph Colouring, Gerrymandering 1 Introductory Remarks I collaborated with Bruno Simeone and his research group for a period of more than 20 years.
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  • Jgrapht--A Java Library for Graph Data Structures and Algorithms

    Jgrapht--A Java Library for Graph Data Structures and Algorithms

    JGraphT - A Java library for graph data structures and algorithms Dimitrios Michail1, Joris Kinable2,3, Barak Naveh4, and John V Sichi5 1Dept. of Informatics and Telematics Harokopio University of Athens, Greece [email protected] 2Dept. of Industrial Engineering and Innovation Sciences Eindhoven University of Technology, The Netherlands [email protected] 3Robotics Institute Carnegie Mellon University, Pittsburgh, USA 4barak [email protected] 5The JGraphT project [email protected] Abstract Mathematical software and graph-theoretical algorithmic packages to efficiently model, analyze and query graphs are crucial in an era where large-scale spatial, societal and economic network data are abundantly available. One such package is JGraphT, a pro- gramming library which contains very efficient and generic graph data-structures along with a large collection of state-of-the-art algorithms. The library is written in Java with stability, interoperability and performance in mind. A distinctive feature of this library is its ability to model vertices and edges as arbitrary objects, thereby permitting natural representations of many common networks including transportation, social and biologi- cal networks. Besides classic graph algorithms such as shortest-paths and spanning-tree algorithms, the library contains numerous advanced algorithms: graph and subgraph iso- morphism; matching and flow problems; approximation algorithms for NP-hard problems arXiv:1904.08355v2 [cs.DS] 3 Feb 2020 such as independent set and TSP; and several more exotic algorithms such as Berge graph detection. Due to its versatility and generic design, JGraphT is currently used in large- scale commercial products, as well as non-commercial and academic research projects. In this work we describe in detail the design and underlying structure of the library, and discuss its most important features and algorithms.