This paper describes an attribute based tabu search heuristic for the generalized minimum spanning tree problem (GMSTP) known to be NP-hard. Given a graph whose vertex set is partitioned into clusters, the GMSTP consists of designing a minimum cost tree spanning all clusters. An attribute based...

Mailbox collection is a complex and costly operation in most postal services. The authors recently undertook a study aimed at improving this operation at the Canada Post Corporation (CPC). This paper describes an improvement to the clustering and routing algorithm currently in use. Various...

The dynamic Pickup and Delivery Problem with Time Windows (PDPTW) is faced by courier companies serving same-day pickup and delivery requests for the transport of letters and small parcels. This article focuses on the dynamic PDPTW for which future requests are not stochastically modelled or...

This article describes a tabu search heuristic for the dial-a-ride problem with the following characteristics. Users specify transportation requests between origins and destinations. They may provide a time window on their desired departure or arrival time. Transportation is supplied by a fleet...