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Full-Text Articles in Computer Engineering

Radar - A Novel Admission Control And Handoff Management Scheme For Multimedia Leo Satellite Networks, Syed Rashidali Rizvi Dec 2005

Radar - A Novel Admission Control And Handoff Management Scheme For Multimedia Leo Satellite Networks, Syed Rashidali Rizvi

Computer Science Theses & Dissertations

Low Earth Orbit (LEO) satellite networks are deployed as an enhancement to terrestrial wireless networks in order to provide broadband services to users regardless of their location. In addition to global coverage, these satellite systems support communications with hand-held devices and offer low cost-per-minute access cost, making them promising platforms for Personal Communication Services (PCS). LEO satellites are expected to support multimedia traffic and to provide their users with some form of Quality of Service (QoS) guarantees. However, the limited bandwidth of the satellite channel, satellite rotation around the Earth and mobility of end-users makes QoS provisioning and mobility management …


Robust And Efficient Localization Techniques For Cellular And Wireless Sensor Networks, Haseebulla M. Khan Dec 2005

Robust And Efficient Localization Techniques For Cellular And Wireless Sensor Networks, Haseebulla M. Khan

Computer Science Theses & Dissertations

Localization in wireless networks refers to a collection of tasks that, collectively, determines the location of a mobile user, striving to hide the effects of mobility from the user and/or application. Localization has become an important issue and has drawn considerable attention, as many applications including E-911, cargo tracking, locating patients, location-sensitive billing, etc., require knowledge of the location of user/objects. It was realized, quite a while back, that extending emergency 911-like services (E-911) to continually growing mobile population is one of the extremely important localization applications. The bulk of the proposed solutions to emergency location management in wireless environments …


A Performance Evaluation Of A Homogeneous Wireless Network Using Opnet It Guru, Roy Lee Gentry Jr. Nov 2005

A Performance Evaluation Of A Homogeneous Wireless Network Using Opnet It Guru, Roy Lee Gentry Jr.

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Roy Lee Gentry Jr. on November 30, 2005.


An Analytical Model Of Mac Protocol Dependant Power Consumption In Multi-Hop Ad Hoc Wireless Sensor Networks, Komlan Egoh Aug 2005

An Analytical Model Of Mac Protocol Dependant Power Consumption In Multi-Hop Ad Hoc Wireless Sensor Networks, Komlan Egoh

Theses

Power efficiency is the most constraining requirement for viable operation of battery-powered networked sensors. Conventionally, dynamic power management (DPM) is used to put sensor nodes into different states such as active, idle, and sleep, each consuming a certain level of power. Within the active state, communication operational states, such as receive and transmit consume different levels of nodal power. This thesis shows how DPM states and protocol operational states can be combined into a single stochastic model to finely evaluate the power consumption performance of a medium access control (MAC) protocol. The model is formulated as a semi-Markov decision process …


Evaluation Of Coding Scheme For Mimo Radar, Suresh Kumar Harikrishnan Aug 2005

Evaluation Of Coding Scheme For Mimo Radar, Suresh Kumar Harikrishnan

Theses

Multiple Input Multiple Output (MIMO) antenna systems have shown a great potential for wireless communication. These systems support high capacity, increased diversity and interference suppression. Recently it has been proposed MIMO constellations for Radar. MIMO Radar is not only a new research field, but also a very promising approach in terms of overcoming Radar Cross Section (RCS) fluctuations with diversity. This thesis explores the potential of coding schemes for MIMO Radar.

The ambiguity functions measures related to MIMO Radar are used to evaluate how much diversity gain can be coherently achieved with certain coding schemes. The results of this analysis …


A Conceptual Framework For Analysis Of System Safety Interoperability Of United States Navy's Combat Systems, Showkat Shanaz Alborzi Jul 2005

A Conceptual Framework For Analysis Of System Safety Interoperability Of United States Navy's Combat Systems, Showkat Shanaz Alborzi

Engineering Management & Systems Engineering Theses & Dissertations

Today's political and military reality requires the optimal use of our legacy systems. The objective is to maximize the effectiveness of our operations by efficient allocation, placement and the use of our forces and war-fighting systems. The synergism drawn from the capabilities of the legacy complex systems enables today's war-fighting needs to be met without substantial increase in cost or resources. This synergism can be realized by the effective integration and interoperation of legacy systems into a larger, more complex system of systems.

However, the independently developed legacy systems in this new tactical environment often have different data types, languages, …


Dream: A Theoretical Analysis, Xueying Qi Jul 2005

Dream: A Theoretical Analysis, Xueying Qi

Computer Science Theses & Dissertations

A Mobile Ad-hoc Network (MANET, for short) is a collection of mobile nodes deployed in support of a short-lived special-purpose operation. Examples include search-and-rescue missions, law-enforcement, multimedia classrooms, and among many others. Unlike cellular or satellite networks, MANET do not rely on any form of pre-existing infrastructure. The mobility of nodes combined with the lack of infrastructure makes routing in MANET notoriously difficult. It was recently suggested that routing in MANET can use to advantage geographic information that the nodes may acquire either by endowing them with a GPS chip or simply by using known localization algorithms. Distance Routing Effect …


Opal: In Vivo Based Preservation Framework For Locating Lost Web Pages, Terry L. Harrison Jul 2005

Opal: In Vivo Based Preservation Framework For Locating Lost Web Pages, Terry L. Harrison

Computer Science Theses & Dissertations

We present Opal, a framework for interactively locating missing web pages (http status code 404). Opal is an example of "in vivo" preservation: harnessing the collective behavior of web archives, commercial search engines, and research projects for the purpose of preservation. Opal servers learn from their experiences and are able to share their knowledge with other Opal servers using the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). Using cached copies that can be found on the web, Opal creates lexical signatures which are then used to search for similar versions of the web page. Using the OAI-PMH to facilitate …


Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya May 2005

Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya

Theses

A wireless ad-hoc network is a cooperative communication network deployed with a specific purpose. It is characterized by dynamically changing topology with no fixed infrastructure which exhibits a perfectly vulnerable state for a number of different kinds of attacks.

This thesis proposes a novel technique of achieving security in wireless mobile ad hoc networks by integrating a simple clustering and a voting mechanism together. The purpose of forming a cluster is to facilitate security in the network and the voting is performed to support the decision making process in the cluster. A procedure of forming small homogenous clusters throughout the …


Using A Pda To Control Home Appliances, Atif Albraiki May 2005

Using A Pda To Control Home Appliances, Atif Albraiki

Honors Capstone Projects - All

The Personal Digital Assistant (PDA) is a handheld device that gives users different organizational capabilities. Over the years, the functionality of PDAs has expanded tremendously to include internet connectivity and different computer applications. The purpose of my honors thesis, combined with my engineering senior design project, was to include a new functionality to the PDA and use it to control different home appliances. The goal of the project was to develop a PDA program that will communicate with a PC program, and have the PC program communicate with a microcontroller to control home appliances. My part of the project was …


Clustering And Hybrid Routing In Mobile Ad Hoc Networks, Lan Wang Apr 2005

Clustering And Hybrid Routing In Mobile Ad Hoc Networks, Lan Wang

Computer Science Theses & Dissertations

This dissertation focuses on clustering and hybrid routing in Mobile Ad Hoc Networks (MANET). Specifically, we study two different network-layer virtual infrastructures proposed for MANET: the explicit cluster infrastructure and the implicit zone infrastructure. In the first part of the dissertation, we propose a novel clustering scheme based on a number of properties of diameter-2 graphs to provide a general-purpose virtual infrastructure for MANET. Compared to virtual infrastructures with central nodes, our virtual infrastructure is more symmetric and stable, but still light-weight. In our clustering scheme, cluster initialization naturally blends into cluster maintenance, showing the unity between these two operations. …


Lightweight Federation Of Non-Cooperating Digital Libraries, Rong Shi Apr 2005

Lightweight Federation Of Non-Cooperating Digital Libraries, Rong Shi

Computer Science Theses & Dissertations

This dissertation studies the challenges and issues faced in federating heterogeneous digital libraries (DLs). The objective of this research is to demonstrate the feasibility of interoperability among non-cooperating DLs by presenting a lightweight, data driven approach, or Data Centered Interoperability (DCI). We build a Lightweight Federated Digital Library (LFDL) system to provide federated search service for existing digital libraries with no prior coordination.

We describe the motivation, architecture, design and implementation of the LFDL. We develop, deploy, and evaluate key services of the federation. The major difference to existing DL interoperability approaches is one where we do not insist on …


Geolocation Of A Node On A Local Area Network, John R. Clarson Mar 2005

Geolocation Of A Node On A Local Area Network, John R. Clarson

Theses and Dissertations

Geolocation is the process of identifying a node using only its Internet Protocol (IP) address. Locating a node on a LAN poses particular challenges due to the small scale of the problem and the increased significance of queuing delay. This study builds upon existing research in the area of geolocation and develops a heuristic tailored to the difficulties inherent in LANs called the LAN Time to Location Heuristic (LTTLH). LTTLH uses several polling nodes to measure latencies to end nodes, known locations within the LAN. The Euclidean distance algorithm is used to compare the results with the latency of a …


Online Multimedia Communication System, Yin-Wei Yang Jan 2005

Online Multimedia Communication System, Yin-Wei Yang

Theses Digitization Project

Online Multimedia Communication System is a project aimed at providing people the ability to store and share their multimedia files. The users and administrator can modify and view the files and database information from a normal web browser. Furthermore, this site offers a secure environment to keep all the users' information private.


Websat: Web-Based Systems Administration Tool, Juyong Jeong Jan 2005

Websat: Web-Based Systems Administration Tool, Juyong Jeong

Theses Digitization Project

Discusses the development of WebSAT (Web-based systems administration tool), a computer network tool that allows systems administrators to create and delete accounts, disable and enable existing accounts, manage disk space conveniently, monitor the status of all network printers, and monitor network security. The WebSAT application was implemented using PHP, a server-side embedded scripting language, with a MySQL database.


An Investigation Into The Use Of B-Nodes And State Models For Computer Network Technology And Education, Gurpreet Kohli Jan 2005

An Investigation Into The Use Of B-Nodes And State Models For Computer Network Technology And Education, Gurpreet Kohli

Theses: Doctorates and Masters

This thesis consists of a series of internationally published, peer reviewed, conference research papers and one journal paper. The papers evaluate and further develop two modelling methods for use in Information Technology (IT) design and for the educational and training needs of students within the area of computer and network technology. The IT age requires technical talent to fill positions such as network managers, web administrators, e-commerce consultants and network security experts as IT is changing rapidly, and this is placing considerable demands on higher educational institutions, both within Australia and internationally, to respond to these changes.


Energy-Efficient Self-Organization Protocols For Sensor Networks, Qingwen Xu Jan 2005

Energy-Efficient Self-Organization Protocols For Sensor Networks, Qingwen Xu

Computer Science Theses & Dissertations

A Wireless Sensor Network (WSN, for short) consists of a large number of very small sensor devices deployed in an area of interest for gathering and delivery information. The fundamental goal of a WSN is to produce, over an extended period of time, global information from local data obtained by individual sensors. The WSN technology will have a significant impact on a wide array of applications on the efficiency of many civilian and military applications including combat field surveillance, intrusion detection, disaster management among many others. The basic management problem in the WSN is to balance the utility of the …