Variable neighborhood search (VNS) is a metaheuristic for solving combinatorial and global optimization problems whose basic idea is a systematic change o...

Let <i>Q = D + A</i> denote the signless Laplacian matrix of a graph <i>G</i> of order <i>n</i>, where <i>D</i> is the diagonal matrix of the degrees and <i...

The <i>Vehicle routing Problem</i> (VRP) was introduced 50 years ago by Dantzig and Ramser under the title "The Truck Dispatching Problem". The study of the ...

Given a set of scheduled flights that must be operated by the same aircraft type, the aircraft routing problem (ARP) consists of building anonymous aircraft ...

This paper presents an efficient approach for realistic modelling of internal transport systems. The weakness of the former methods in tracking the traffic w...

Khalifeh, Yousefi-Azari, Ashrafi and Wagner [European J. Combin. 30 (2009) 1149-1163] conjectured that for a connected graph <i>G</i> on <i>n</i> vertices...

The proximity <img src="/cgi-bin/mimetex.cgi?\pi"> of a graph <i>G</i> is the minimum average distance from a vertex of <i>G</i> to all others. Similarly, th...

In the <i>Vehicle Routing Problem with Deliveries, Selective Pickups and Time Windows</i>, the set of customers is the union of <i>delivery customers</i> and...

During the last three decades, the computer has been widely used in spectral graph theory. Many results about graph eigenvalues were first conjectured, and i...

In-house production or outsourcing are important strategic decisions for planning production and capacity in business organizations. Outsourcing to overseas ...

It is observed that mutations in the formulations of test problems over time are not infrequent. Ensuing problems are illustrated with examples from geometri...

Finding maximum likelihood parameter values for Finite Mixture Model (FMM) is often done with the Expectation Maximization (EM) algorithm. However the choice...

We consider an inventory routing problem in discrete time where a supplier has to serve a set of customers over a time horizon. A capacity constraint for th...

A profit and a demand are associated with each arc of a set of profitable arcs of a given graph. A travel time is associated with each arc of the graph. A fl...

The Dutch railway network experiences about three large disruptions per day on average. In this paper, we present an algorithm to reschedule the crews when s...

The <i>Generalized Vehicle Routing Problem</i> (GVRP) is an extension of the classical <i>Vehicle Routing Problem</i> (VRP) in which the vertex set is partit...

This work presents an exact branch-cut-and-price algorithm for the vehicle routing problem with time windows (VRPTW) where the well-known clique inequalities...

We compare the effectiveness and efficiency of alternative operational dispatching policies that are integrated into the design phase of a circular material ...

This paper presents an overview of the column generation method developed at the GERAD research center in Montr&#39;eal for solving large scale vehicle routing ...

We consider a maritime inventory routing problem in the liquefied natural gas (LNG) business. Here, an actor is responsible for the routing of the fleet of s...