IE-OPIM Joint Graduate Seminar
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IE-OPIM Joint Graduate Seminar: Ayhan Özgür Toy (Bilgi University)

 A Serial Inventory System with Lead Time Dependent Backordering: A Reduced-State Approximation

Date: Wednesday, November 25, 2015
Time: 13:40 – 14:30
Location: FENS G035

Abstract: We consider a serial inventory system under continuous review (S-1,S) policies at all echelons facing Poisson demand generated from a population in which customers have waiting time tolerances. In case of a stock out at the lower echelon, a customer, upon arrival, is quoted the remaining lead time. If the waiting time tolerance of the customer exceeds the quotation, the demand is backordered; otherwise, it is lost. Using the method of supplementary variables, we define the stochastic process representing the inventory system and construct the operating characteristics of the latter. Based on the solution structures for the special cases, we propose an approximate solution for the general serial system with lead time dependent backordering. An extensive numerical study indicates that the proposed approximation performs very well. Our numerical study provides additional insights about the sensitivity and allocation of stock levels across echelon.

Bio: Özgür Toy is a faculty member in the Industrial Engineering Department of İstanbul Bilgi University. He received his PhD degree at Bilkent University, MS degree at the US Naval Post Graduate School, and BS degree at the Naval Academy. His research interests are supply chain management, inventory control and quality control systems. His detailed CV can be found at