Bruno Oliveira

A heuristic framework for a class of vehicle routing problems

Categories Combinatorial Optimization, Meta Heuristics, Transportation Tags , , ,

We propose GenericILS, a general-purpose heuristic framework for generating high-quality upper bounds for Vehicle Routing Problems whose pricing subproblems are modeled, in column-generation-based exact algorithms, as resource-constrained shortest path problems described through Resource Extension Functions (REFs), the standard device for encoding constraints in branch-and-price algorithms. GenericILS reuses REFs implemented for the exact method, without a … Read more

Hybrid iterated local search algorithm for the vehicle routing problem with lockers

Categories Combinatorial Optimization, Integer Programming, Meta Heuristics Tags , , ,

In the Vehicle Routing Problem (VRP) with Lockers, the vertices in a graph are divided into two key subsets: a customer set and a locker set, with lockers serving as alternative delivery points for the customer’s parcel. This paper presents a generic VRP with lockers, where a customer’s parcel can be delivered either to its … Read more

New cuts and a branch-cut-and-price model for the Multi Vehicle Covering Tour Problem

Categories Combinatorial Optimization, Cutting Plane Approaches, Integer Programming Tags , , , ,

The Multi-Vehicle Covering Tour Problem (m-CTP) involves a graph in which the set of vertices is partitioned into a depot and three distinct subsets representing customers, mandatory facilities, and optional facilities. Each customer is linked to a specific subset of optional facilities that define its coverage set. The goal is to determine a set of … Read more