Detailed schedule

Thursday 30 January:

• p-center problem with failure foresight and capacity constraints
  Antonio M. Rodriguez-chia (Université Libre de Bruxelles (ULB))
  Co-authors: I. Espejo (U. de Cádiz); A. Marín (U. de Murcia)
  
• Improved Results for the Traveling Umpire Problem
  Sam Van Malderen (KU Leuven, Department of Computer Science, CODeS & iMinds-ITEC)
  Co-authors: Tony Wauters, Greet Vanden Berghe
  
• Integrated task scheduling and personnel rostering problems
  Pieter Smet (KU Leuven, campus Gent)
  Co-authors: Greet Vanden Berghe
  

• A high-level, modular and declarative modeling framework for routing problems
  Christophe Ponsard (CETIC)
  Co-authors: Renaud De Landtsheer, Yoann Guyot
  
• Cloud optimization with OptaPlanner
  Geoffrey De Smet (Red Hat)
  
• Using factorial number system to solve permutation optimization problems
  Mohand Mezmaz (University of Mons)
  Co-authors: R. Leroy, M. Mezmaz, N. Melab and D. Tuyttens
  

• The City Bike Repositioning Problem
  Darpana Dilip (Unversity of Antwerp)
  Co-authors: Prof. dr. Kenneth Sörensen
  
• Exact and meta-heuristic algorithm for the multi-depot heterogeneous dial-a-ride problem
  Kris Braekers (Universiteit Hasselt)
  Co-authors: An Caris, Gerrit K. Janssens
  
• Operational Effects of Variations in Service Level Criteria for the Dial-a-Ride Problem
  Yves Molenbruch (Hasselt University)
  Co-authors: An Caris, Kris Braekers
  

• ILS for water distribution network optimisation
  Annelies De Corte (University of Antwerp)
  Co-authors: Kenneth Sörensen
  
• Effects of Carbon Footprint Reduction on Supply Chain Network Design
  Jean-sébastien Tancrez (Louvain School of Management, Université catholique de Louvain)
  Co-authors: Joana M. Comas-Marti, Ralf W. Seifert
  
• A system-dynamics analysis of the energy transition in Belgium after Fukushima
  Pierre L. Kunsch (ULB)
  Co-authors: Jean Friesewinkel
  

• Early detection of university students in potential difficulty
  Anne-sophie Hoffait (HEC - University of Liege)
  Co-authors: M;Schyns
  
• MediaCycle : A tool for interactive browsing of multimedia libraries.
  Xavier Siebert (Faculté Polytechnique de Mons)
  Co-authors: Thierry Ravet, Christian Frisson, Stéphane Dupont
  
• First species counterpoint music generation with VNS and vertical viewpoints
  Dorien Herremans (Universiteit Antwerpen)
  Co-authors: Kenneth Sörensen, Darrell Conklin
  
• A Choquet integral for the comparison of decisional maps
  Valerie Brison (UMONS)
  Co-authors: Marc Pirlot
  

• Motivations for the development of a multi-objective algorithm configurator
  Nguyen Thi Thanh Dang (KU Leuven KULAK)
  Co-authors: Patrick De Causmaecker
  
• Multi-Objective Optimization for the Design of 3D-Stacked Integrated Circuits
  Nguyen Anh Vu Doan (Université libre de Bruxelles)
  Co-authors: Dragomir Milojevic, Frederic Robert, Yves De Smet
  
• Design safer and greener road projects by using a multiobjective optimization approach
  Renaud Sarrazin (University of Brussels)
  Co-authors: Yves De Smet
  
• Deconstructing Multi-Objective Evolutionary Algorithms
  Manuel LÓpez-ibaÑez (Université Libre de Bruxelles)
  Co-authors: Leonardo C. T. Bezerra and Thomas Stützle
  

• A relax-and-fix heuristic for the three-dimensional bin-packing model with transportation constraints
  Célia Paquay (HEC - University of Liege)
  Co-authors: M. Schyns and S. Limbourg
  
• A Heuristic Approach to Minimize the Number of Shifts in Container Ship Stowage Plans
  Jan Christiaens (KU Leuven)
  Co-authors: J. Verstichel, G. Vanden Berghe
  
• Time Development of new Hydrogen Transmission Pipeline Networks for Franc
  Daniel De Wolf (Université du Littoral Côte d'Opale)
  Co-authors: Jean ANDRE, Stephane AURAY,Mohamed-Mahmoud MEMMAH
  
• Solution methods for the cycle trip planning problem
  Cédric Verbeeck (Ghent University)
  Co-authors: P. Vansteenwegen, E.-H. Aghezzaf
  

• Heuristics for Varian's Index
  Bart Smeulders (KU Leuven)
  Co-authors: Frits C.R. Spieksma
  
• Investment in Shares by MULTIMOORA Multiple Objectives Optimization
  Willem K. M. Brauers (Vilnius Gediminas Technical University and University of Antwerp)
  
• Estimating collaborative profits under varying partner characteristics and strategies
  Christine Vanovermeire (University of Antwerp)
  Co-authors: Daniel Palhazi Cuervo; Kenneth Sörensen
  
• Gain sharing in a collaborative selective vehicle routing problem
  Christof Defryn (University of Antwerp)
  Co-authors: Kenneth Sörensen
  

• A Branch-and-Price Algorithm for the Network Pricing Problem with Connected Toll Arcs
  Alessia Violin (Université Libre de Bruxelles)
  Co-authors: Bernard Fortz, Martine Labbé
  
• Maximizing User Benefits by Changes in Incomplete Networks
  Corrinne Luteyn (KU Leuven)
  Co-authors: Pieter Vansteenwegen
  
• Models for traffic engineering with multiple spanning tree protocols
  Martim Moniz (Université Libre de Bruxelles)
  Co-authors: Bernard Fortz; Luís Gouveia
  
• Optimal capacitated ring trees
  Alessandro Hill (University of Antwerp)
  Co-authors: Stefan Voss
  

• Quadratic reformulations of nonlinear binary optimization problems
  Yves Crama (HEC - University of Liege)
  Co-authors: M. Anthony, E. Boros, A. Gruber
  
• A Conic Optimization Approach to SKU Rationalization
  Tanguy Kegelart (Université catholique de Louvain, Louvain School of Management)
  Co-authors: Mathieu Van Vyve
  
• A hybrid piecewise-linear/Newton's method with corrected Jacobian matrix for multi-period water production and distribution in large networks
  Derek Verleye (Ghent University)
  Co-authors: Derek Verleye
  

• Learning a majority rule model from large sets of assignment examples
  Olivier Sobrie (University of Mons / Ecole Centrale Paris)
  Co-authors: Olivier Sobrie
  
• Understanding people’s preferences: an integrated algorithm for the optimal design of discrete choice experiments with partial profiles
  Daniel Palhazi Cuervo (University of Antwerp)
  Co-authors: Peter Goos, Roselinde Kessels and Kenneth Sörensen
  
• An empirical distribution-based approximation of PROMETHEE II's net flow scores
  Stefan Eppe (Université libre de Bruxelles)
  Co-authors: Yves De Smet
  

• An iterative approach to generate k dissimilar VRP solutions
  Luca Talarico (University of Antwerp)
  Co-authors: K. Sörensen, J. Springael
  
• Improved Model for the Maximum Covering and Patrol Routing Problem
  Reginald Dewil (KU Leuven)
  Co-authors: P. Vansteenwegen, D. Cattrysse, D. Van Oudheusden
  
• The impact of preprocessing for solving the train routing problem
  Thijs Dewilde (KU Leuven)
  Co-authors: S. Burggraeve, T. Ameye, P. Sels, D. Cattrysse, P. Vansteenwegen
  

• Number of non-equivalent colorings of a graph
  Hadrien Mélot (Université de Mons, Departement d'Informatique, Faculté des Sciences)
  Co-authors: A. Hertz
  
• Price on symmetrisation and average distance
  Romain Absil (UMons)
  
• Solving the Elementary Longest Path as a Mixed Integer Program
  Quoc Trung Bui (Université catholique de Louvain )
  Co-authors: Yves Deville, Pham Quang Dung
  

• Dynamic Programming for Scheduling Locks in Sequence
  Ward Passchyn (KU Leuven)
  Co-authors: F.C.R. Spieksma
  
• A Combinatorial Benders' decomposition for the lock scheduling problem
  Jannes Verstichel (KU Leuven campus Gent)
  Co-authors: Joris Kinable, Patrick De Causmaecker, Greet Vanden Berghe
  
• A dynamic programming algorithm for a robotic cell problem with batch transfer
  Nacira Chikhi (USTHB /AMCD&RO UVHC/LAMIH)
  Co-authors: M. Abbas, A. Bekrar, R. Benmansour and S.Hanafi
  

• Diffusion approximation of the virtual delay in two queueing systems coupled by their service process
  Ben Lauwens (Koninklijke Militaire School)
  
• Analysis of a discrete-time queue with constant service capacity
  Sabine Wittevrongel (Ghent University)
  Co-authors: H. Bruneel, W. Rogiest, J. Walraevens and S. Wittevrongel
  
• A discrete-time queueing model with constant service times and blocking
  Willem Mélange (Ghent University)
  Co-authors: Herwig Bruneel, Dieter Claeys, Joris Walraevens
  

• On weak ordering by choosing from valued outranking relations
  Raymond Bisdorff (University of Luxembourg)
  
• An interpretable axiomatization of the h-index
  Thierry Marchant (Ghent University)
  Co-authors: Denis Bouyssou
  
• Multicriteria clustering: a summary of recent investigations
  Yves De Smet (Université Libre de Bruxelles)
  

• Competitive analysis of on-line algorithms : applications to Operations Research.
  Claudio Telha Cornejo (Université Catolique de Louvain)
  Co-authors: Mathieu Van Vyve
  
• Novel Formulations for Stackelberg Security Games
  Carlos Casorrán-amilburu (ULB)
  Co-authors: Bernard Fortz, Martine Labbé, Fernando Ordóñez
  
• On the complexity of separation: the three-index assignment problem
  Frits Spieksma (KU Leuven)
  Co-authors: T. Dokka and I. Mourtos
  

• CP Approach for the Multi-Item Discrete Lot-Sizing Problem with Sequence-Dependent Changeover Costs
  Vinasetan Houndji (Université Catholique de Louvain)
  Co-authors: Pierre Schaus, Laurence Wolsey
  
• Local search approaches for 2D nesting problems
  Tony Wauters (KU Leuven, Department of Computer Science, CODeS - iMinds-ITEC)
  Co-authors: Sam Van Malderen, Greet Vanden Berghe
  
• Exact resolution of the Cover Printing Problem
  Arnaud Vandaele (UMONS, Faculté Polytechnique)
  Co-authors: Daniel Tuyttens
  

• The carry-over effect does exist in tennis
  Dries Goossens (Ghent University)
  Co-authors: Frits Spieksma
  
• Alternative Pairwise Decomposition Techniques for Label Ranking
  Massimo Gurrieri (UMONS)
  Co-authors: Philippe Fortemps, Xavier Siebert
  
• Constrained Clustering using Column Generation
  Behrouz Babaki (KU Leuven)
  Co-authors: Tias Guns, Siegfried Nijssen
  
• Geometrical lower bound for the nonnegative rank of slack matrices
  Julien Dewez (Université catholique de Louvain)
  Co-authors: Nicolas Gillis, François Glineur
  Abstract:
  The nonnegative rank of an element-wise nonnegative matrix is the minimum number of nonnegative rank-one factors needed to reconstruct it exactly. Computing this rank and a related factorization is NP-hard. However it can be used to describe an extension of a convex polytope, i.e., a higher-dimensional polytope which projects onto the original polytope, with minimum number of facets. These extensions for polytopes have important applications in combinatorial optimization. More precisely, many combinatorial optimization problems can be formulated as the optimization of a linear objective function over a polytope which may have a very large number of facets (possibly increasing exponentially with the size of the problem). Because of the high number of facets, computing the optimal solution of this linear optimization problem can be very time consuming. However, if one can find an extension for this polytope with a moderate number of facets (growing for example polynomially with the size of the problem), one can solve the optimization problem over the extension efficiently, and project its optimal solution back to the original polytope of feasible solutions. Therefore, we would like to know the extension complexity of the polytope of feasible solutions, i.e., the minimum number of facets of any extension of this polytope. In particular, if the extension complexity grows exponentially with the size of the problem, then the polytope of feasible solutions does not admit any extension with a polynomial number of facets and we will not able to solve the problem in polynomial time with this approach. Crucially, the extension complexity of a polytope is also the nonnegative rank of a particular matrix called the slack matrix. The extension complexity is then also NP-hard to compute in general. In this talk, we introduce a new geometrical lower bound on the extension complexity of a polytope which relies on the monotone behavior of the f-vector of a convex polytope under projections (where the f-vector is the collection of the numbers of k-faces of the polytope). This new lower bound improves upon existing lower bounds and, in some cases, implies optimality of the best known extension.
  

• Hyper-Criticism: A critical reflection on todays Hyper-heuristics.
  Willem Van Onsem (KU Leuven)
  Co-authors: Bart Demoen and Patrick De Causmaecker
  
• Towards a Lightning-Inspired Meta-heuristic
  Mohand Mezmaz (University of Mons)
  Co-authors: M. Mezmaz, A. Vandaele, D. Tuyttens, S. Itani and N. Melab
  
• A simple and high-performing competitive--cooperative hybrid algorithm for black-box continuous optimization
  Thomas Stützle (Université Libre de Bruxelles (ULB))
  Co-authors: Tianjun Liao
  
• Some Heuristic Algorithms for the 0-1Knapsack Sharing Problem
  Christophe Wilbaut (University of Valenciennes)
  Co-authors: S. Hanafi, A. Fréville,B. Haddar, M. Khemakhem
  

• Horizontal cooperation in logistics : Order sharing through joint route planning
  Lotte Verdonck (Hasselt University)
  Co-authors: An Caris, Katrien Ramaekers, Gerrit K. Janssens
  
• Multi-period vehicle assignment with stochastic load availability
  Thierry Pironet (HEC - University of Liege)
  Co-authors: Yves CRAMA
  
• An Exact Bi-directional Dynamic Programming Algorithm for an Elementary Shortest Path Problem with Variable Service Start Time
  Hande Küçükaydin (University of Liège)
  Co-authors: Yasemin Arda, Yves Crama
  
• Incorporating axle weight restrictions in a two-dimensional CVRP
  Hanne Pollaris (Hasselt University)
  Co-authors: Kris Braekers, An Caris, Gerrit K. Janssens
  

• IP Techniques for Nurse Rostering Problem
  Tulio Toffolo (KU Leuven)
  Co-authors: Haroldo G. Santos, Rafael Martinelli, Rafael A.M. Gomes, Greet Vanden Berghe
  
• Using computer simulation to test a short stay unit
  Gilles Sinnaeve (Université Catholique de Louvain)
  Co-authors: Claire Beguin, Philippe Chevalier & Marianne Philippe
  
• SIMEDIS disaster management simulator: aeronautical catastrophe
  Christophe Ullrich (Royal Military Academy)
  Co-authors: C. Ullrich, F. Van Utterbeeck, E. Dhondt and M. Debacker
  
• Integrating patient-to-room assignment planning with elective admission scheduling
  Wim Vancroonenburg (KU Leuven)
  Co-authors: Patrick De Causmaecker, Frits Spieksma, Greet Vanden Berghe