We show the optimality of state dependent echelon base stock policies in uncapacitated serial inventory systems with Markov modulated demand and Markov modulated stochastic leadtimes in the absence of order crossing. Our results cover finite time horizon problems as well as infinite time horizon formulations, with either a discounted or an average cost criterion. We employ a novel approach, bas...

We show the optimality of state-dependent echelon base-stock policies in uncapacitated serial inventory systems with Markov-modulated demand and Markov-modulated stochastic lead times in the absence of order crossing. Our results cover finite-time horizon problems as well as infinite-time horizon formulations, with either a discounted or an average cost criterion. We employ a novel approach, ba...

We consider energy efficient base station sleeping and clustering problems in cooperative cellular networks where clusters of base stations jointly transmit to users. Our key idea of energy saving is to exploit a spatio-temporal fluctuation of traffic demand, which is to use minimal energy to provide capacity only slightly greater than varying traffic demand. Then, energy saving is possible wit...

I this paper we examine the impact of different types of advance demand information on firm profit and on the benefits of resource flexibility. Specifically, we consider a firm that must choose capacities of resources that will be used to satisfy stochastic demand for multiple products, where demands follow a multivariate normal distribution. Prior to the capacity decision, the firm receives in...

A stream is a continuous version of a supply chain. It is like a series inventory system, but stock can be held at any point along a continuum, not just at discrete stages. We assume stationary parameters and aim to minimize the long-run average total cost. We show that a stationary continuous-stage echelon base-stock policy is optimal. That is, at each geographic point along the supply stream,...

We consider a capacitated supply system that produces a single item that is demanded by several classes of customers. Each customer class may have a different backorder cost, so stock allocation arises as a key decision problem. We model the supply system as a multicustomer make-to-stock queue. Using dynamic programming, we show that the optimal allocation policy has a simple and intuitive stru...

In this work, optimal control theory is used to derive the optimal production rate in a manu‐ facturing system presenting the following features: the demand rate during a certain period depends on the demand rate of the previous period (dependent demand), the demand rate depends on the inventory level, items in inventory are subject to deterioration, and the firm can adopt a periodic or a conti...

We examine a single-item, periodic-review inventory system with stochastic leadtimes, in which a replenishment order is delivered immediately or one period later, depending probabilistically on costly effort. The objective is to determine an inventory policy and an effort-choice strategy that minimize the expected total costs. Our analytical and computational analysis suggests that (i) a state-...

Nominal government debt, including the monetary base, is a residual claim to government surpluses. Thus, the value of Þat money can be determined in a completely frictionless economy, just like the price of stock. The main theoretical objection to this Þscal theory of the price level is that it mistreats the government’s intertemporal budget constraint. I show that the valuation equation for no...

A finite horizon inventory model for a single deteriorating product is studied. The system is under periodic review and there is a positive fixed order cost associated with any placed order. The demand in successive periods is independent and identically distributed. A constant fraction of any positive leftover stock is deteriorated at the end of each period. Any unsatisfied demand is partially...