Dr. Sıla Çetinkaya from Southern Methodist University will present at the Seminar Monday November 27 at 1:15pm in Room 114 of the W. A. Baker Chemistry Research Building (CRB). Dr. Çetinkaya’s presentation title, abstract, and biographical sketch are below.
Title: On the Integration of Inbound Replenishment and Outbound Transportation Decisions: Premises, Models, and Dynamic Optimization
Author: Sıla Çetinkaya
Location: W. A. Baker Chemistry Research Building (CRB) Room 114
Date: Monday, November 27
Time: 1:15pm – 2:15pm
Abstract: We consider a joint stock replenishment and shipment scheduling problem applicable under a vendor-managed inventory (VMI) contract where the vendor has flexibility over the timing and quantity of resupply at a group of retailers located in a given geographical region. The retailers face stochastic demands. Under the VMI contract of interest, employing a temporal shipment consolidation strategy allows the vendor to hold smaller orders from the retailers and to release them in a combined shipment to realize transportation scale economies. Although the general class of problems of interest has been investigated using renewal theory in the previous literature, computation of exact optimal policies has remained an open problem for over fifteen years. We formulate the problem via a stochastic dynamic programming approach. We examine the optimal joint policy specifying the vendor’s inbound replenishment and outbound dispatch quantities in successive periods so that transportation economies of scale due to shipment consolidation are realized without excessive inventory holding and/or order delay. We characterize the structure of the optimal policy as a zoned, state-dependent threshold policy that falls in a new class of policies in stochastic inventory control theory. The results extend the existing theory and concepts of generalized convexity while also generalizing Scarf’s seminal work on the notion of K-convexity and optimality of (s,S) policies.
Biographical Sketch: Sila Çetinkaya is Chair and Professor of EMIS in the SMU Lyle School of Engineering. She holds courtesy appointments with ITOM in the SMU Cox School of Business and with Internal Medicine in the UT Southwestern Medical Center. She also serves as Senior Fellow in the SMU Hunt Institute for Engineering and Humanity. She joined SMU in 2014 from TAMU—after 17 years of service—where she was Professor of Industrial and Systems Engineering. She obtained her Ph.D. in Management Science and Systems in 1996 from McMaster University in Canada. She received an MS in Industrial Engineering in 1991 from Bilkent University and a B.S. in Industrial Engineering in 1989 from Istanbul Technical University in Turkey. Dr. Çetinkaya’s research interests include supply chain and healthcare operations, stochastic optimal control theory, and applied probability. Her publications appeared in reputable outlets of industrial engineering and management science including Operations Research, Management Science, Interfaces, Production and Operations Management, IISE Transactions, and Naval Research Logistics, among others. Her research and teaching activities have been funded by multiple government and industry grants. Her early career accomplishments were recognized by NSF CAREER Award in 2001 and IISE Outstanding Young Industrial Engineer Award in 2003. Çetinkaya was named IISE Fellow in 2012 for professional leadership and outstanding contributions to industrial engineering. She is a department editor of IISE Transactions and an associate editor of Naval Research Logistics.