Dr. Halit Üster from the Department of Engineering Management, Information, and Systems at Southern Methodist University will present the IMSE seminar on Monday, November 25, 2019 at 1:15pm in Nedderman Hall, Room 106. Dr. Üster’s presentation title, abstract, and biographical sketch are below.
All students and faculty are encouraged to attend. Attendance is expected for GTAs and on-campus GRAs. There will be signature sheets for GTA’s located in the room. Please sign in to note your attendance.
Title: Capacitated Relay Network Design with Link Imbalance Constraints in Truckload Transportation: A Lagrangean Decomposition Approach
Author: Halit Üster
Location: Nedderman Hall Room 106
Date: Monday, November 25, 2019
Time: 1:15pm
Abstract: High driver turnover and driver shortage are chronic and costly problems in truckload trucking industry. Extended on-the-road times with low-quality of life, irregular schedules, and low get-home rates for the drivers are commonly attributed as the main culprits in both academic and industry literature. Among its other benefits, use of a relay network can help to alleviate the turnover, and in turn, the shortage problems by reducing the drivers’ away-from-home times and providing them with predictable schedules without sacrificing their mileage accumulation on which a driver’s pay is based. In this study, we consider the strategic design of a relay network that can provide an effective underlying structure to facilitate the intended efficient truckload operations acceptable to all stakeholders (drivers, company, and customers). In doing so, we explicitly consider design characteristics that are important in the operational setting including driver tour lengths, load imbalance on the relay connections, and the route circuity levels. To solve our resulting mixed integer programming model, we develop a Lagrangean Decomposition based algorithm that produces tight lower bounds and incorporates an effective heuristic to generate near-optimal solutions. Our numerical tests illustrate that large size problems can be solved with small optimality gaps within reasonable runtimes. Moreover, based on our computational experiments, we present analyses on the influence of input data parameters on algorithmic performance and the network characteristics, trade-offs between imbalance requirements and cost components, and the effects of link capacity on design.
Biographical Sketch: Halit Üster is a Professor in the Department of Engineering Management, Information, and Systems (EMIS) at Southern Methodist University (SMU). His research interests are in the areas of logistics, design of networked systems, and applied optimization. His publications appeared in Transportation Science, IIE Transactions, Naval Research Logistics, INFORMS Journal on Computing, and IEEE/ACM Transactions on Networking, among others. His research has been funded by National Science Foundation, US Department of Agriculture, and industry. Previously, he was on the faculty of ISE Department at Texas A&M until 2014 and was a visiting professor at the IEMS Department of Northwestern during 2009-2010 where he was named Eshbach Society Distinguished Visiting Scholar in the McCormick School of Engineering & Applied Science. He was a recipient of the Caterpillar Teaching Excellence Award in Look College of Engineering of TAMU in 2011 and INFORMS Moving Spirit Award. He serves as an Associate Editor for IISE Transactions and Transportation Science and also serves INFORMS community in varying capacities. Üster is a member of INFORMS and IISE.
Industrial, Manufacturing, and Systems Engineering (IMSE) Department 