Showing papers in "Electronic Notes in Discrete Mathematics in 2018"

TL;DR: In this article, the authors proposed a genetic algorithm to address a green vehicle routing problem (G-VRP) which aims to minimise the CO2 emissions per route by incorporating elements of local and population search heuristics.

TL;DR: This paper presents the scenario which a drone works in collaboration with a delivery truck to distribute parcels, and an implementation of the Randomized Variable Neighborhood Descent (RVND) heuristic is used as a local search to obtain the problem solution.

TL;DR: The proposed algorithm uses Randomized Variable Neighborhood Descent (RVND) as local search method and it is tested in classical instances of the problem and the obtained results are presented and discussed in this paper.

TL;DR: Two state-of-the-art multiobjective evolutionary algorithms are presented to solve a variant of the urban waste collection problem considering priorities and the conflicting goals of minimizing the total distance while maximizing the Quality of Service.

TL;DR: Improve previously known compact models and present computational results, based on telecommunication backbone networks, showing that the proposed models are much more efficiently solved and enable us to obtain optimal solutions for networks up to 200 nodes and p values up to 20 critical nodes within a few minutes in the worst cases.

TL;DR: The main goal of this paper is the definition of new classes of valid inequalities for strengthening the linear formulation of the 2E-CVRP, the two-echelon variant of the well known Capacitated Vehicle Routing Problem.

TL;DR: This paper addresses the optimization of cable connections between turbines in an offshore wind park with new features that have been recently proposed by Vattenfall's experts using a Mixed-Integer Linear Programming paradigm.

TL;DR: This work proposes an Integer Linear Programming (ILP) model for RTTSP based on Light Robustness, an effective technique introduced in [Fischetti, M., and M. Monaci, Light robustness], and test the proposed ILP model on real-world data of the Wuhan-Guangzhou high-speed railway corridor under different demand scenarios.

TL;DR: This study proposes a new column generation model with lightpaths (i.e., paths provisioned with a given number of spectrum slots in the context of RSA), in which the lightpath generators can be efficiently solved using a shortest path algorithm.

TL;DR: This work formulate the CSPTP as an integer linear programming (ILP) model and present valid inequalities for the problem and shows that the ILP model consistently outperforms existing exact algorithms for the C SPTP and finds optimal solutions for most instances.

TL;DR: This short paper proposes a simpler Variable Neighborhood Search heuristic where all the computational effort is spent on searching for feasible solutions and shows that the proposed heuristic is competitive with the best heuristic in the literature.

TL;DR: This paper addresses the Hybrid Flow Shop Problem through the Multi-objective Variable Neighborhood Search metaheuristic (MOVNS) and considere two evaluation criteria under simultaneous analysis: the minimization of the makespan and the weighted sum of tardiness.

TL;DR: The GVRSP considers heterogeneous vehicles, time-varying traffic congestion, capacity constraints and the delivery can be fractionated, and allows vehicles to stop on arcs, so vehicle is allowed to travel an arc in multiple time periods.

TL;DR: An adaptive local search heuristic is proposed in which, in each iteration, a Greedy Randomized Adaptive Search Procedure is used to generate the initial solution, and a mean-risk model in which only the first and the second moment of the travel times distribution are required to be known.

TL;DR: This article presents an entropy-based summary function which may help to decide the most relevant Betti numbers from finite samples of a given manifold.

TL;DR: A heuristic solution algorithm based on a fairly general graph model is developed for the retrieval of articles from a warehouse to fulfill customer orders of a large e-commerce business.

TL;DR: Preliminary results show that biclustering can help to identify features with low class-discrimination power, which it is useful for reducing the complexity of QSAR models without losing prediction accuracy.

TL;DR: This work considers the problem of placing Virtual Network Function instances (services) and routing the demands so as to guarantee that demands can reach the requested services.

TL;DR: A hybrid heuristic that combines ideas from the sample average approximation method and from relax-and-fix approaches is proposed and preliminary tests based on randomly generated instances show that it performs better than the classical sample approximation algorithm for hard instances.

TL;DR: A MILP formulation, an exact and 2-approximation algorithms, and test them using classical instances from the literature to find a robust solution that minimizes the maximal regret over all possible combinations of values for the columns benefit.

TL;DR: The statistical analysis indicates that the proposed ILS-VND hybrid metaheuristic outperforms the references metaheuristics for the most scenarios.

TL;DR: A variable neighborhood descent (VND) inspired algorithm which improves the state-of-art biased random-key genetic algorithm (BRKGA) for the three-dimensional bin packing problem and shows significantly superior average fitness through the generations.

TL;DR: This paper addresses a novel hybrid metaheuristic combining the Genetic algorithm and Modified Variable Neighborhood Search for the vehicle routing problem with cross-docking by proposing four shaking and two neighbourhood structures in a modified version of the VNS.

TL;DR: A new formulation where the route of each vehicle is decomposed into a sequence of simpler substructures called clusters is investigated, mitigating the combinatorial explosion of feasible solutions.

TL;DR: Two Integer Linear Programming formulations for the Minimum Sum Coloring Problem are studied and it is shown that the linear programming relaxation of the second formulation provides tight lower bounds which allow to solved some hard instances of the literature.

TL;DR: A sequential value correction heuristic is proposed that outperforms the benchmark algorithm specifically designed for the same problem and some insight is given on the structure of the Pareto-optimal sets of the considered classes of instances.

TL;DR: Integral preserving property for a subclass of analytic functions defined by this q-operator is proved and special new q-integral operators are obtained as consequences.

TL;DR: The asymptotics of the number of possible endpoints of a random walk on a metric graph with incommensurable edge lengths is found.

TL;DR: In this paper, the authors classified empty 4-simplices of width at least three and width two, and showed that there are two two-parameter families that project to the second dilation of a unimodular triangle.

TL;DR: It is demonstrated that the result by Zelikovskij concerning Konigs problem for abelian permutation groups, reported in a recent survey, is false and two results are proposed which concern the same topic in a more general setting.