In the United States, many transit agencies are considering integrating their demand-responsive service with traditional fixed-route service. In some cases, it may be advantageous to the transit agency or to the passenger to coordinate traditional demand-responsive transit service with fixed -route service. The demand-responsive service connects passengers from their origin to the fixed route s...

Title of dissertation: PARALLEL AND SERIAL ALGORITHMS FOR VEHICLE ROUTING PROBLEMS Christopher Groër, Doctor of Philosophy, 2008 Dissertation directed by: Professor Bruce Golden Robert H. Smith School of Business The vehicle routing problem (VRP) is a widely studied combinatorial optimization problem that has many applications. Due to its intrinsic difficulty and the size of problems encountere...

The vehicle routing problem with time windows (VRPTW) is an extension of the vehicle routing problem (VRP) with earliest, latest, and service times for customers. The VRPTW routes a set of vehicles to service customers having earliest, latest service times. The objective of the problem is to minimize the number of vehicles and the distance travelled to service the customers. The constraints of ...

We introduce a new concept in column generation for handling complex large scale optimization problems, called two-stage column generation, where columns for the compact and extensive formulation are simultaneously generated. The new framework is specifically conceived for tackling complex problems that cannot be efficiently solved by standard column generation and exploits the relationship bet...

Vehicle speed plays a significant role on fuel consumption and greenhouse gas emissions in freight transportation. We study a general joint routing and speed optimization problem with the goal of minimizing the total fuel, emission, and labor costs; the fuel consumption and emission rate is allowed to be an arbitrary strictly convex function of vehicle speed. We propose a novel set partitioning...

In this paper, we study an integrated production scheduling and delivery routing problem. The manufacturer has to schedule a set of jobs on a single machine without preemption and to deliver them to multiple customers. A single vehicle with limited capacity is used for the delivery. For each job are associated: a processing time, a size and a specific customer location. The problem consists the...

Column generation algorithms have been specially designed for solving mathematical programs with a huge number of variables. Unfortunately, this method suffers from slow convergence that limits its efficiency and usability. Several accelerating approaches are proposed in the literature such as stabilization-based techniques. A more classical approach, known as “intensification”, consists in ins...

The purpose of this paper is to develop structural classi ̄cation of Stochastic Vehicle Routing Problem (SVRP) by di®erent domains and attributes. This research used a systematic review and meta-analysis on SVRP literatures. This includes browsing relevant researches and publications, screening related articles, identifying domains, attributes and categorising the articles based on the identi ̄ed...