This research developed a Water Quality Index (WQI) for public supply in the Vale do Rio Pardo Region, RS, Brazil (WQI-VRP), from database of 13th Regional Health Coordination, totaling 1175 samples. A filtration process resulted 285 samples with variables free residual chlorine, turbidity, apparent color, pH, fluoride, total coliforms and Escherichia coli. For water consumption purposes, by Sa...

In this paper, a novel methodology is proposed to solve a cooperative multi-depot vehicle routing problem. We establish a mathematical model for multi-owner VRP in which each owner (i.e. player) manages single or multiple depots. The basic idea consists of offering an option that owners cooperatively manage the VRP to save their costs. We present cooperative game theory techniques for cost savi...

In order to conquer the premature convergence problem and lower the cost of computing of the basic Ant Colony Algorithm (ACA), we present an adaptive ant colony algorithm, named AACA, coupled with a Pareto Local Search (PLS) algorithm and apply to the Vehicle Routing Problem (VRP) and Capacitated VRP (CVRP). By using the information entropy, the algorithm adjusts the pheromone updating strategy...

As a key factor of logistics distribution, vehicle routing problem (VRP) is a hot research topic in management and computation science. In this paper the principle and algorithm process of firefly algorithm are introduced in detail. Then the algorithm process and solving steps are designed for vehicle routing problem with time windows (VRPTW), including the coding and design of disturbance mech...

We describe a special variant of the Vehicle Routing Problem (VRP), where there are many customers per road segment. A metaheuristic tabu search algorithm for the VRP is given, and aggregation of customers is used to better the performance, with respect to both time and solution quality. The methods are tested on test instances from the literature as well as a portfolio of new test instances es...

Vehicle Routing Problem (VRP) is one of the key issues in optimization of modern logistics system. In this paper, a modified VRP model with hard time window is established and a Hybrid Optimization Algorithm (HOA) based on Fractal Space Filling Curves (SFC) method and Genetic Algorithm (GA) is introduced. By incorporating the proposed algorithm, SFC method can find an initial and feasible solut...

In this paper the classical Vehicle Routing Problem (VRP) is extended to cover the more realistic case of uncertainty about customer demands. This case is modelled as a VRP with stochastic demands and tackled with a heuristic solution approach based on Ant Colony Optimization (ACO). The main issues studied in this paper are the modelling of the uncertainty (i) in terms of its influence on the p...

This work introduces the Green Vehicle Routing Problem (GVRP). The GVRP is an extension of the well-known vehicle routing problem (VRP). Moreover, the GVRP includes an objective function that minimizes weighted distance. Minimizing weighted distance reduces fuel consumption and consequently CO2 emissions. Therefore, the GVRP is more environmentally friendly than traditional versions of the VRP....