A supplier has a periodic review inventory system that provides several lead-time options to its customers. The inventory replenishment lead time is a multiple of the inventory review cycle. Customers are classified into two groups: short lead-time customers requiring the product immediately and long lead-time customers who allow the supplier the flexibility to deliver immediately or in the nex...

In this paper, we describe the first computationally efficient policies for stochastic inventory models with lost sales and replenishment lead times that admit worst-case performance guarantees. In particular, we introduce dual-balancing policies for lost-sales models that are conceptually similar to dual-balancing policies recently introduced for a broad class of inventory models in which dema...

Energy harvesting has attached considerably attention for its wide application in wireless green communications. Equipped with a rechargeable battery, a source node can harvest energy from ambient environments and rely on this free and regenerative energy supply to transmit packets. Due to the uncertainty of available energy from harvesting, however, it could induce intolerably large latency an...

The WiMAX, also known as IEEE 802.16, provides a mechanism for deploying high-speed wireless mesh network, (an ubiquitous wireless network) in metropolitan areas. WiMAX technology can be used as “last mile ubiquitous” broadband connections to deliver streaming audio or video to clients. Thus, Quality of Service (QoS) is very important for WiMAX networks. Providing QoS in multi-hop WiMAX network...

The practical experiences reveal that the inflation is non-deterministic and variable. Therefore, a mathematical model for the optimal production for an inventory control system of deteriorating items is formulated under time-varying and stochastic inflation environment. The demand rate is a function of inflation and the time horizon is finite. In the real situation, some but not all customers ...

Multiuser diversity refers to a type of diversity present across different users in a fading environment. This diversity can be exploited by scheduling transmissions so that users transmit when their channel conditions are favorable. Using such an approach leads to a system capacity that increases with the number of users. However, such scheduling requires centralized control. In this paper, we...

In wireless networks, multiple stations contend for access to the shared channel. In the cases of collisions, the associated collision cost is much higher than wired networks since stations cannot detect the collision without explicit feedback from the receiver. For this reason, more efficient contention resolution algorithms are desired for wireless networks to reduce the collision probability...

Packet Fair Queueing (PFQ) algorithms are the most popular and well studied scheduling algorithms for integrated services networks for two reasons: (1) With reservation, they can provide per-flow end-to-end delay guarantees for real-time traffic flows. (2) Without reservation, they can provide protection among competing best-effort flows while allowing dynamic bandwidth sharing. However, PFQ al...

Fiber-Wireless (FiWi) networks typically combine an optical access network with a wireless access network so as to build on the respective strengths of the optical and wireless network technologies. Prior analytical throughput-delay studies of FiWi networks have typically considered heavy-loaded traffic models, i.e., constantly backlogged source nodes. In contrast, in this paper we present a mo...

This paper shows how to set basestock levels in a multiproduct system with setups and random yield. The system is represented by a polling model and the inventory level of each product is controlled using a basestock policy. When the queue is empty, the inventory level is equal to the basestock level, thus the server will continue to serve the queue until it is empty. If the capacity of the que...