In pickup and delivery problems vehicles have to transport loads from origins to destinations without transshipment at intermediate locations In this paper we discuss several characteristics that distinguish them from standard vehicle routing problems and present a survey of the problem types and solution methods found in

The problem of designing a set of routes with minimum cost to serve a collection of customers with a fleet of vehicles is a fundamental challenge when the number of customers to be dropped or picked up is not known during the planning horizon. The purpose of this paper is to develop a vehicle routing Problem (VRP) model that addresses stochastic simultaneous pickup and delivery in the urban pub...

Pickup and delivery problems discussed in the literature often allow for only particularly simple solutions in terms of the sequence of visited locations. We study the very simplest pickup and delivery paths which are concatenations of short patterns visiting one or two requests. This restricted variant, still N P -hard, is close to the traveling salesman problem with the additional choice of w...

We consider a pickup and delivery vehicle routing problem commonly encountered in real-world logistics operations. The problem involves a set of practical complications that have received little attention in the vehicle routing literature. In this problem, there are multiple carriers and multiple vehicle types available to cover a set of pickup and delivery orders, each of which has multiple pi...

Through the analysis of Travelling Salesman Problem with Pickup and Delivery (TSPD) in the related research, two kinds of logistics systems including whole logistics system and partial logistics system under one-to-many logistic network are considered. And mathematical model is set up, then, nested cost optimization model is set up in order to meet the constraint condition of nested order cycle...

We consider a network in which a set of vehicles is responsible for the pickup and delivery of messages that arrive according to Poisson process with message pickup and delivery locations distributed uniformly at random in a region of bounded area A. The vehicles are required to pickup and deliver the messages so that the average delay is minimized. In this paper, we provide lower bounds on the...