Composite-variable modeling for large-scale problems in transportation and logistics

Numerous important real-world problems are found in the areas of transportation and logistics. Many of these problems pose tremendous challenges due to characteristics such as complex networks, tightly constrained resources, and very large numbers of heavily inter-connected decisions. As a result, mathematical models can be critical in solving these problems. These models, however, can be computationally challenging or even intractable. In this thesis we discuss how greater tractability can sometimes be achieved with composite-variable models - models in which individual binary variables encompass multiple decisions. In Part I, we discuss common challenges found in solving large-scale transportation and logistics problems. We introduce the idea of composite variables and discuss the potential benefits of composite-variable models. We also note some of the drawbacks of these models and discuss approaches to addressing these drawbacks. In Parts II and III, we demonstrate these ideas using two real-world examples, one from airline planning and the other from service parts logistics. We build on our experience from these two applications in Part IV, providing some broader insights for composite-variable modeling. We focus in particular on the dominance property seen in the service parts logistics example and on the fact that we can relax the integrality of the composite variables in the airline planning example. In both cases, we introduce broader classes of problems in which these properties can also be found. We offer conclusions in Part V.

Department dc:contributor.department

Sloan School of Management.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2002

Author dc:creator

• Cohn, Amy Ellen Mainville, 1969-

Advisor dc:contributor.advisor

• Cynthia Barnhart.

• Sloan School of Management.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/8529

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/8529