The Capacitated Arc Routing Problem (CARP) is a very hard vehicle routing problem raised for instance by urban waste collection. In addition to the total route length (the only criterion minimized in the academic problem), waste management companies seek to minimize also the length of the longest trip. A bi-objective genetic algorithm is presented for this more realistic CARP, never studied bef...

This paper studies an arc routing problem with capacity constraints and time-dependent service costs. This problem is motivated by winter gritting applications where the ‘‘timing’’ of each intervention is crucial. The exact problem-solving approach reported here first transforms the arc routing problem into an equivalent node routing problem. Then, a column generation scheme is used to solve th...

Arc routing problems (ARPs) arise naturally in several applications where streets require maintenance, or customers located along road must be serviced. The undirected rural postman problem (URPP) is to determine a least cost tour traversing at least once each edge that requires a service. When demands are put on the edges and this total demand must be covered by a fleet of identical vehicles o...

Arc Routing Problems on mixed graphs have been modelled in the literature either using just one variable per edge or associating to each edge two variables, each one representing its traversal in the corresponding direction. In this paper, and using the Mixed General Routing Problem as an example, we compare theoretical and computationally both formulations as well as the lower bounds obtained ...

The increasing use of electric vehicles in road and air transportation, especially last-mile delivery city mobility, raises new operational challenges due to the limited capacity batteries. These limitations impose additional driving range constraints when optimizing distribution mobility plans. During last years, several researchers from Computer Science, Artificial Intelligence, Operations Re...

The Capacitated Arc Routing Problem with Refill Points (CARP-RP) is a new variant of the Capacitated Arc Routing Problem (CARP). In a CARP situation, the vehicle servicing arcs has a finite capacity, and hence has to return to the depot or a secondary station to be refilled (or emptied). In contrast, in the CARP-RP, the vehicle servicing arcs must be refilled on the spot by using a second vehic...

Mixed Capacitated Arc Routing Problem (MCARP) models arise in distribution or collecting problems where activities are performed by vehicles, with limited capacity, and are continuously distributed along some predefined links (routes, streets) of an associated network. Considering directed as well as undirected required links, it is a generalization of the well known Capacitated Arc Routing pro...

This article explores a structural neighborhood decomposition for arc routing problems, in which the decisions about traversal orientations during services are made optimally as part of neighbor evaluation procedures. Using memory structures, bidirectional dynamic programming, and lower bounds, we show that a large neighborhood involving classical moves on the sequences of services along with o...

The paper studies hybrid solution methods for a general class of arc routing problems arising in the context of garbage collection. Important differences of basic local optimizers for arc oriented compared to node oriented problems are worked out. The initial problem is split into its routing (sequencing) and clustering part. For both problems meta-procedures that make use of the modified local...