IE-OPIM Joint Graduate Seminar: Murat Fadıloğlu (Yaşar University)
“Continuous Time Control of Tandem Production Lines”
Joint work with Özge Büyükdağlı
Date: Wednesday, October 14, 2015
Time: 13:40 – 14:30
Location: FENS G035
Abstract: We consider the problem of production control and stock rationing in a make-to-stock production system with several customer classes that generate independent Poisson demands. The production system under consideration consists of a tandem production line with a finished goods buffer at the end. The tandem line is composed of workstations with exponential production times and intermediate buffers. At decision epochs, in conjunction with the stock allocation decision for the finished goods, the control specifies whether to continue or stop production at each workstation. We model the system using continuous-time Markov control methodology. Via uniformization technique, we transform the problem into a discrete-time dynamic program. We propose an efficient and succinct LP formulation to the infinite horizon problem. Through numerical experiments, we investigate the character of the optimal policy. We then consider random machine breakdowns for the workstations of the tandem line. We report how the introduction of the breakdowns changes the optimal production and rationing policies in order to hedge the system against the additional uncertainty. The number of stations that can be considered with our approach is limited due to the curse of dimensionality that plagues as well the performance analysis of similar systems. However, observations from the smaller size experiments carries the prospect of obtaining insights that can prove useful with larger size systems.
Bio: Murat Fadıloğlu is Professor of Industrial Engineering at Yaşar University. He holds a B.S. in Electrical Engineering from Bilkent University, and a Ph.D. in Industrial and Systems Engineering from University of Florida. His research interests include performance evaluation of inventory/production systems, queueing models, stochastic modeling, dynamic programming, optimal control and supply chain management. He teaches courses on stochastic modeling, probability theory, analytical reasoning, and algorithms and computation.