Radio Communications

In the last decades the restless evolution of information and communication technologies (ICT) brought to a deep transformation of our habits. The growth of the Internet and the advances in hardware and software implementations modified our way to communicate and to share information. In this book, an overview of the major issues faced today by researchers in the field of radio communications is given through 35 high quality chapters written by specialists working in universities and research centers all over the world. Various aspects will be deeply discussed: channel modeling, beamforming, multiple antennas, cooperative networks, opportunistic scheduling, advanced admission control, handover management, systems performance assessment, routing issues in mobility conditions, localization, web security. Advanced techniques for the radio resource management will be discussed both in single and multiple radio technologies; either in infrastructure, mesh or ad hoc networks

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

ACUTA Journal of Telecommunications in Higher Education

In This Issue UConn Looks at Little Details for Big Savings A Framework for Managing Best Practices Auditing, Honesty, and Big Savings Leveraging SIP within Existing Networks: Reflecting on the University Network Merging Faces of Telecom Service Providers How Three Schools Make Profitable Use of the Web Developing Accounting and Planning Systems to Control Network Costs lnstitutional Excellence Award: The Advanced Network Services Registry at KU Are You Ready for Best Practices? Interview President\u27s Message From the Executive Directo

High-Throughput Air-to-Ground Connectivity for Aircraft

Permanent connectivity to the Internet has become the defacto standard in the second decade of the 21st century. However, on-board aircraft connectivity is still limited. While the number of airlines offering in-flight connectivity increases, the current performance is insufficient to satisfy several hundreds of passengers simultaneously. There are several options to connect aircraft to the ground, i.e. direct air-to-ground, satellites and relaying via air-to-air links. However, each single solution is insufficient. The direct air-to-ground coverage is limited to the continent and coastal regions, while the satellite links are limited in the minimum size of the spot beams and air-to-air links need to be combined with a link to the ground. Moreover, even if a direct air-to-ground or satellite link is available, the peak throughput offered on each link is rarely achieved, as the capacity needs to be shared with other aircraft flying in the same coverage area. The main challenge in achieving a high throughput per aircraft lies in the throughput allocation. All aircraft should receive a fair share of the available throughput. More specifically, as an aircraft contains a network itself, a weighted share according to the aircraft size should be provided. To address this problem, an integrated air-to-ground network, which is able to provide a high throughput to aircraft, is proposed here. Therefore, this work introduces a weighted-fair throughput allocation scheme to provide such a desired allocation. While various aspects of aircraft connectivity are studied in literature, this work is the first to address an integrated air-to-ground network to provide high-throughput connectivity to aircraft. This work models the problem of throughput allocation as a mixed integer linear program. Two throughput allocation schemes are proposed, a centralized optimal solution and a distributed heuristic solution. For the optimal solution, two different objectives are introduced, a max-min-based and a threshold-based objective. The optimal solution is utilized as a benchmark for the achievable throughput for small scenarios, while the heuristic solution offers a distributed approach and can process scenarios with a higher number of aircraft. Additionally, an option for weighted-fair throughput allocation is included. Hence, large aircraft obtain a larger share of the throughput than smaller ones. This leads to fair throughput allocation with respect to the size of the aircraft. To analyze the performance of throughput allocation in the air-to-ground network, this work introduces an air-to-ground network model. It models the network realistically, but independent from specific network implementations, such as 5G or WiFi. It is also adaptable to different scenarios. The aircraft network is studied based on captured flight traces. Extensive and representative parameter studies are conducted, including, among others, different link setups, geographic scenarios, aircraft capabilities, link distances and link capacities. The results show that the throughput can be distributed optimally during high-aircraft-density times using the optimal solution and close to optimal using the heuristic solution. The mean throughput during these times in the optimal reference scenario with low Earth orbit satellites is 20 Mbps via direct air-to-ground links and 4 Mbps via satellite links, which corresponds to 10.7% and 1.9% of the maximum link throughput, respectively. Nevertheless, during low-aircraft-density times, which are less challenging, the throughput can reach more than 200 Mbps. Therefore, the challenge is on providing a high throughput during high-aircraft-density times. In the larger central European scenario, using the heuristic scheme, a minimum of 22.9 Mbps, i.e. 3.2% of the maximum capacity, can be provided to all aircraft during high-aircraft-density times. Moreover, the critical parameters to obtain a high throughput are presented. For instance, this work shows that multi-hop air-to-air links are dispensable for aircraft within direct air-to-ground coverage. While the computation time of the optimal solution limits the number of aircraft in the scenario, larger scenarios can be studied using the heuristic scheme. The results using the weighted-fair throughput allocation show that the introduction of weights enables a user-fair throughput allocation instead of an aircraft-fair throughput allocation. As a conclusion, using the air-to-ground model and the two introduced throughput allocation schemes, the achievable weighted-fair throughput per aircraft and the respective link choices can be quantified

A Model for Managing Information Flow on the World Wide Web

Metadata merged with duplicate record (http://hdl.handle.net/10026.1/330) on 20.12.2016 by CS (TIS).This is a digitised version of a thesis that was deposited in the University Library. If you are the author please contact PEARL Admin ([email protected]) to discuss options.This thesis considers the nature of information management on the World Wide Web. The web has evolved into a global information system that is completely unregulated, permitting anyone to publish whatever information they wish. However, this information is almost entirely unmanaged, which, together with the enormous number of users who access it, places enormous strain on the web's architecture. This has led to the exposure of inherent flaws, which reduce its effectiveness as an information system. The thesis presents a thorough analysis of the state of this architecture, and identifies three flaws that could render the web unusable: link rot; a shrinking namespace; and the inevitable increase of noise in the system. A critical examination of existing solutions to these flaws is provided, together with a discussion on why the solutions have not been deployed or adopted. The thesis determines that they have failed to take into account the nature of the information flow between information provider and consumer, or the open philosophy of the web. The overall aim of the research has therefore been to design a new solution to these flaws in the web, based on a greater understanding of the nature of the information that flows upon it. The realization of this objective has included the development of a new model for managing information flow on the web, which is used to develop a solution to the flaws. The solution comprises three new additions to the web's architecture: a temporal referencing scheme; an Oracle Server Network for more effective web browsing; and a Resource Locator Service, which provides automatic transparent resource migration. The thesis describes their design and operation, and presents the concept of the Request Router, which provides a new way of integrating such distributed systems into the web's existing architecture without breaking it. The design of the Resource Locator Service, including the development of new protocols for resource migration, is covered in great detail, and a prototype system that has been developed to prove the effectiveness of the design is presented. The design is further validated by comprehensive performance measurements of the prototype, which show that it will scale to manage a web whose size is orders of magnitude greater than it is today

2009-2010, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2009-2010.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1429/thumbnail.jp

2006-2007, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2006-2007.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1426/thumbnail.jp

2010-2011, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2010-2011.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1430/thumbnail.jp

2007-2008, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2007-2008.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1427/thumbnail.jp