Seminar

Abstract

This talk presents a continuous mathematical model for the Green Vehicle Routing Problem. The presented model is a more general case of the discretized pollution routing problem widely studied in the literature, that determines the routes and schedules for a fleet of fossil-fuel powered vehicles under a comprehensive objective function including both operational and environmental costs. We present a linearization method based on an inner polyhedral approximation to the non-linear relation between the travel time and travel speed. The approximation error in this linearization method is guaranteed to be within a given parameter ε, which can be as low as 0.01% in our experiments. We also demonstrate how the non-linear consumption rate (FCR) of a fossil-fuel powered vehicle can be bounded linearly by the speed and load of the vehicle while ensuring an approximation error within the same parameter ε. Based on these linearization methods, we propose a ε-accurate linear mathematical model in which decision variables such as travel speeds, travel times, arrival/departure/waiting times, vehicle loads, and FCRs are optimized concurrently on the continuous domain. A theoretical analysis is provided to show that solutions found by the new model are feasible and guaranteed to be within a predefined maximum gap of the optimal ones, and the optimal solutions of many instances are reported for the first time.

Short Bio

Abdullah Konak is a Professor of Information Sciences and Technology at the Pennsylvania State University, Berks.  Dr. Konak received his degrees in Industrial Engineering, B.S. from Yildiz Technical University, Turkey, M.S. from Bradley University, and Ph.D. from the University of Pittsburgh. Dr. Konak also held visiting positions at Lehigh University and the Chinese University of Hong Kong.    

Dr. Konak’s current research interest is in the application of Operations Research techniques to complex problems, including such topics as network design, network reliability, facilities design, green logistics, and data mining.  Dr. Konak has published papers in leading journals such as Operations Research Letters, Informs Journal on Computing, Europan Journal of Operations Research, Computers and Operations Research, IIE Transactions, IEEE Transactions on Reliability, International Journal of Production Research, and Production Economics.  He has been a principal investigator in sponsored projects from the National Science Foundation, the National Security Agency, the US Department of Labor, and Venture Well. 

Dr. Konak currently teaches courses on Database Management Systems, Cybersecurity, Agent Based Modelling, and Entrepreneurship. He is a member of INFORMS and IEEE.