This paper presents an inventory-control model which includes a Markovian model of the supply system. As that system evolves over time, so do the replenishment leadtimes. The optimal policy has the same structure as in standard models, but its parameters change dynamically to reflect current...

We study a basic (r, q) system, in which the demand is a Poisson process and the leadtimes are independent, identically-distributed random variables. The key issue is the joint effect of the leadtime variance and the lot size q on performance. We know that, under a simple base-stock policy (with...

This paper studies a periodic-review, serial supply chain in which materials are ordered and shipped according to (R,nQ) policies. Three information scenarios are considered, depending on the level of information available: echelon, local, and quasilocal. In the echelon scenario, each stage can...

We consider a multiproduct assemble-to-order (ATO) system, in which inventory is kept only at the component level and the finished products are assembled in response to customer demands. In addition to stochastic demand for finished products, the system experiences stochastic returns of subsets...

Consider an inventory system with multiple supply sources and Poisson demand. The replenishment lead times from each source are stochastic, representing congestion and disruption. We develop performance evaluation and optimization tools for a family of reasonable order policies. These policies...

This paper explores the interest rate sensitivity of the prices of bonds and other securities when the instantaneous interest rate follows a Markov process. We show that whenever the interest rate describes a diffusion process the sensitivity of zero-coupon bonds increases with maturity. More...