In this paper, we consider the mobility effect with a jointly optimal design of cross-layer congestion control, routing and scheduling for ad-hoc networks. We first formulate the rate constraint and scheduling constraint. In this way, we use multi-commodity flow variables. Then formulate resource allocation in networks with fixed wireless channel and single-rate devices. Because of entrance of ...

In this work, we explore network traffic shaping mechanisms that deliver packets at pre-determined intervals; allowing the network interface to transition to a lower power consuming sleep state. We focus our efforts on commodity devices, IEEE 802.11b ad hoc mode and popular streaming formats. We argue that factors such as the lack of scheduling clock phase synchronization among the participants...

The paper studies the core-Walras equivalence problem in the commodity space framework of Banach spaces, allocations being defined as Pettis integrable functions. In particular, a core-Walras equivalence result for a certain class of commodity spaces is established, without requiring that the commodity space be separable. The class covered by this result includes the Lp(μ) spaces, 1 ≤ p < ∞, μ ...

A well known problem with revealed preference methods is that when data are found to satisfy their restrictions it is hard to know whether this should be viewed as a triumph for economic theory, or a warning that these conditions are so undemanding that almost anything goes. This paper allows researchers to make this distinction. Our approach builds on theoretical support in the form of an axio...

The government of Malawi in 2004 initiated an ICT-based Malawi Agricultural Commodity Exchange (MACE), a market information service project, to improve access by farmers to market information. MACE was intended to improve the efficiency of agricultural markets as part of the strategy to improve food security. This study uses quantitative methods to examine whether MACE has contributed to effici...

This paper presents a new low cost e-mail system for the HF band (3–30 MHz) based on free software and commodity hardware. The core of the system is a 2500 bps OFDM data modem enhanced by turbo codes and a powerful ARQ protocol. The modem has been deeply tested with a Watterson HF channel simulator [?, ], studying the impact of different configurable parameters and comparing its codification st...

In an economy with commodity-pairwise trading posts and transaction costs, commodity money is endogenously determined in general equilibrium. Absent double coincidence of wants, the lowtransaction cost commodity (with the narrowest proportional bid/ask price spread) becomes the common medium of exchange. JEL Classification: C62, E40

Executive Summary The lack of market information represents a significant impediment to market access especially for smallholder poor farmers: it substantially increases transaction costs and reduces market efficiency. For any one crop, the marketing chain consists of multiple middlemen, each taking a margin at every stage of the chain, and price variations in space and time are often large and...

Renewable resources from agriculture have the potential to be an attractive alternative source of raw materials for industry. Their efficient use is important, since acreage for cultivation is limited. For such applications, supply planning can pose specific problems for processors of raw materials, because many crops are only seasonally available. Harvest quality and quantity as well as sales ...