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Old Dominion University

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Articles 91 - 120 of 213

Full-Text Articles in Digital Communications and Networking

An Extensible Framework For Creating Personal Archives Of Web Resources Requiring Authentication, Matthew Ryan Kelly Jul 2012

An Extensible Framework For Creating Personal Archives Of Web Resources Requiring Authentication, Matthew Ryan Kelly

Computer Science Theses & Dissertations

The key factors for the success of the World Wide Web are its large size and the lack of a centralized control over its contents. In recent years, many advances have been made in preserving web content but much of this content (namely, social media content) was not archived, or still to this day is not being archived,for various reasons. Tools built to accomplish this frequently break because of the dynamic structure of social media websites. Because many social media websites exhibit a commonality in hierarchy of the content, it would be worthwhile to setup a means to reference this …


Visualizing Digital Collections At Archive-It, Kalpesh Padia Jul 2012

Visualizing Digital Collections At Archive-It, Kalpesh Padia

Computer Science Theses & Dissertations

Archive-It, a subscription service from the Internet Archive, allows users to create,maintain, and view digital collections of web resources. The current interface of Archive-It is largely text-based, supporting drill-down navigation using lists of URIs.While this interface provides good searching capabilities, it is not efficient for browsing. In the absence of keywords, a user has to spend large amount of time trying to locate a web page of interest. In order to provide a better visual experience to the user, we have studied the underlying characteristics of Archive-It collections and implemented six different visualizations (treemap, time cloud, bubble chart, image plot, …


Using The Web Infrastructure For Real Time Recovery Of Missing Web Pages, Martin Klein Jul 2011

Using The Web Infrastructure For Real Time Recovery Of Missing Web Pages, Martin Klein

Computer Science Theses & Dissertations

Given the dynamic nature of the World Wide Web, missing web pages, or "404 Page not Found" responses, are part of our web browsing experience. It is our intuition that information on the web is rarely completely lost, it is just missing. In whole or in part, content often moves from one URI to another and hence it just needs to be (re-)discovered. We evaluate several methods for a \justin- time" approach to web page preservation. We investigate the suitability of lexical signatures and web page titles to rediscover missing content. It is understood that web pages change over time …


A Framework For Dynamic Traffic Monitoring Using Vehicular Ad-Hoc Networks, Mohammad Hadi Arbabi Jul 2011

A Framework For Dynamic Traffic Monitoring Using Vehicular Ad-Hoc Networks, Mohammad Hadi Arbabi

Computer Science Theses & Dissertations

Traffic management centers (TMCs) need high-quality data regarding the status of roadways for monitoring and delivering up-to-date traffic conditions to the traveling public. Currently this data is measured at static points on the roadway using technologies that have significant maintenance requirements. To obtain an accurate picture of traffic on any road section at any time requires a real-time probe of vehicles traveling in that section. We envision a near-term future where network communication devices are commonly included in new vehicles. These devices will allow vehicles to form vehicular networks allowing communication among themselves, other vehicles, and roadside units (RSUs) to …


Data Aggregation And Dissemination In Vehicular Ad-Hoc Networks, Khaled Ibrahim Apr 2011

Data Aggregation And Dissemination In Vehicular Ad-Hoc Networks, Khaled Ibrahim

Computer Science Theses & Dissertations

Vehicular Ad-Hoc Networks (VANETs) are a fast growing technology that many governments and automobile manufacturers are investing in to provide not only safer and more secure roads, but also informational and entertainment-based applications for drivers. The applications developed for VANETs can be classified into multiple categories (safety, informational, entertainment). Most VANET applications, regardless of their category, depend on having certain vehicular data(vehicular speed, X position and Y position) available. Although these applications appear to use the same vehicular data, the characteristics of this data (i.e., amount, accuracy, and update rate) will vary based on the application category. For …


Performance Analysis For Wimax Wireless Systems With Multiple Receive Antennas, Selcuk Taskin Apr 2011

Performance Analysis For Wimax Wireless Systems With Multiple Receive Antennas, Selcuk Taskin

Electrical & Computer Engineering Theses & Dissertations

Broadband wireless access has become the best way to meet the growing demand for fast Internet connections. WiMAX is one of the most promising broadband access technologies that allows fast deployment as well as low maintenance costs. WiMAX allows efficient use available bandwidth by using orthogonal frequency division multiplexing (OFDM) which is an efficient multi-carrier modulation technique. Diversity is a method for improving the reliability of a signal in fading environments by using two or more communication channels and is usually achieved by multiple antenna techniques.

In this thesis, receiver side diversity combining methods are studied and the performance of …


A Study Of Diversity Techniques For Lte Wireless Systems, Ferhat Kaplan Apr 2011

A Study Of Diversity Techniques For Lte Wireless Systems, Ferhat Kaplan

Electrical & Computer Engineering Theses & Dissertations

The demand of attaining information and the wish to communicating anytime and anywhere has caused numerous innovations in the digital communication world. Today, approximately half of the people on earth somehow use wireless technology which is in every part of our lives. LTE (Long Term Evolution) and WIMAX (Worldwide Interoperability for Microwave Access) standards are the two leading wireless technologies, which support high data rates, multimedia applications, and voice video communications at very high speeds, also called 4G cellular systems in the global market.

These high expectations from wireless technology have revealed multiple antenna techniques which improve the performance and …


Electronic Warfare By Using Unmanned Aerial Vehicles, Aydin Meric Apr 2011

Electronic Warfare By Using Unmanned Aerial Vehicles, Aydin Meric

Electrical & Computer Engineering Theses & Dissertations

Technology continues to evolve rapidly by the day. Developments in technology should be followed closely if a country wants to become more powerful. Nowadays nobody can afford to ignore the importance of Electronic Warfare and Unmanned Aerial Vehicles (UAV) in military applications. Both of them play a crucial role in military operations that they can change the course of a war.

There are different kinds of Electronic Warfare methods that can be applied according to the situations and any evolving circumstances. In the beginning Electronic Warfare was used mainly for defensive purposes, but these days Electronic Warfare is used for …


Solving The Vehicle Re-Identification Problem By Using Neural Networks, Tanweer Rashid Apr 2011

Solving The Vehicle Re-Identification Problem By Using Neural Networks, Tanweer Rashid

Computational Modeling & Simulation Engineering Theses & Dissertations

Vehicle re-identification is the process by which vehicle attributes measured at one point on a road network are compared to vehicle attributes measured at another point in an effort to match vehicles without using any unique identifiers such as license plate numbers. A match is made if the two measurements are estimated to belong to the same vehicle. Vehicle attributes can be sensor readings such as loop induction signatures, or they can also be actual vehicle characteristics such as length, weight, number of axles, etc. This research makes use of vehicle length, travel time, axle spacing and axle weights for …


Design And Implement A Cost-Effective Wireless Communication Project On A Pic Training System, Steve Hsiung, Walter F. Deal, Lacides Agustin Osorio, Mathew Henderson Jan 2011

Design And Implement A Cost-Effective Wireless Communication Project On A Pic Training System, Steve Hsiung, Walter F. Deal, Lacides Agustin Osorio, Mathew Henderson

Engineering Technology Faculty Publications

Wireless communication becomes popular and widely used in almost every electronic product in our daily life. The RF communication is one of the major wireless applications in consumer products. Usually, it is integrated with an embedded system (microcontroller) to control various applications such as temperature sensing, data logging, data exchange, actuator activation, and user interaction wirelessly. A project based model can be used as an effective instructional strategy to enhance learning about complex RF concepts and technologies. The project method can lead to improved understanding and create interest by actively engaging the student with hands-on and problem solving and critical …


Special Issue On Information Dissemination And New Services In P2p Systems, Min Song, Sachin Shetty, Wenbin Jiang, E. K. Park Jan 2011

Special Issue On Information Dissemination And New Services In P2p Systems, Min Song, Sachin Shetty, Wenbin Jiang, E. K. Park

Electrical & Computer Engineering Faculty Publications

Information dissemination is an important P2P application that has received considerable research attention in recent years. P2P information dissemination systems range from simple file sharing applications to more complex systems that allows users to securely and efficiently publish, organize, index, search, update and retrieve data in a distributed storage medium. For complex P2P information dissemination systems, there is a need for features which include security, anonymity, fairness, scalability, resource management, and organization capabilities. For effective information dissemination, following features of P2P systems and infrastructure need to be updated: distributed object location and routing mechanisms, novel approaches to content replication, caching …


Vehicular Ad Hoc Networks, Syed R. Rizvi, Stephan Olariu, Christina M. Oinotti, Shaharuddin Salleh, Mona E. Rizvi, Zainab Zaidi Jan 2011

Vehicular Ad Hoc Networks, Syed R. Rizvi, Stephan Olariu, Christina M. Oinotti, Shaharuddin Salleh, Mona E. Rizvi, Zainab Zaidi

Computer Science Faculty Publications

(First paragraph) Vehicular ad hoc networks (VANETs) have recently been proposed as one of the promising ad hoc networking techniques that can provide both drivers and passengers with a safe and enjoyable driving experience. VANETs can be used for many applications with vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. In the United States, motor vehicle traffic crashes are the leading cause of death for all motorists between two and thirty-four years of age. In 2009, the National Highway Traffic Safety Administration (NHTSA) reported that 33,808 people were killed in motor vehicle traffic crashes. The US Department of Transportation (US-DOT) estimates that …


Spectrum Adaptation In Cognitive Radio Systems With Operating Constraints, Deepak R. Joshi Jan 2011

Spectrum Adaptation In Cognitive Radio Systems With Operating Constraints, Deepak R. Joshi

Electrical & Computer Engineering Theses & Dissertations

The explosion of high-data-rate-demanding wireless applications such as smart-phones and wireless Internet access devices, together with growth of existing wireless services, are creating a shortage of the scarce Radio Frequency (RF) spectrum. However, several spectrum measurement campaigns revealed that current spectrum usage across time and frequency is inefficient, creating the artificial shortage of the spectrum because of the traditional exclusive "command-and-control" model of using the spectrum. Therefore, a new concept of Cognitive Radio (CR) has been emerging recently in which unlicensed users temporarily borrow spectrum from the licensed Primary Users (PU) based on the Dynamic Spectrum Access (DSA) technique that …


Providing Location Security In Vehicular Ad Hoc Networks, Gongjun Yan Apr 2010

Providing Location Security In Vehicular Ad Hoc Networks, Gongjun Yan

Computer Science Theses & Dissertations

Location is fundamental information in Vehicular Ad-hoc Networks (VANETs). Almost all VANET applications rely on location information. Therefore it is of importance to ensure location information integrity, meaning that location information is original (from the generator), correct (not bogus or fabricated) and unmodified (value not changed). We present validation mechanisms to provide location integrity for VANETs. In the initial mechanism, we assume that all vehicles are equipped with a radar, a GPS receiver, and a transceiver. Since radar has a limited radar range and transceiver has a limited transmission range, we build network cells as a security unit as well …


A Genetic Algorithm Approach For Optimized Routing, Pavithra Gudur Apr 2010

A Genetic Algorithm Approach For Optimized Routing, Pavithra Gudur

Electrical & Computer Engineering Theses & Dissertations

Genetic Algorithms find several applications in a variety of fields, such as engineering, management, finance, chemistry, scheduling, data mining and so on, where optimization plays a key role. This technique represents a numerical optimization technique that is modeled after the natural process of selection based on the Darwinian principle of evolution. The Genetic Algorithm (GA) is one among several optimization techniques and attempts to obtain the desired solution by generating a set of possible candidate solutions or populations. These populations are then compared and the best solutions from the set are retained. Subsequently, new candidate solutions are produced, and the …


Embedding Gps Data Into Speech Signal, Kagan Can Apr 2010

Embedding Gps Data Into Speech Signal, Kagan Can

Electrical & Computer Engineering Theses & Dissertations

Communication between deployed troops is very important on a battlefield. The real time knowledge of the location of the communicating patter is also very important in many situations because if you do not know the exact position of your units you cannot give correct orders. A minor error in an order can cause fatal results or lead to defeat. In many cases the position of the units is given through the speech channel by simply speaking the coordinates of the location. This can cause misunderstandings due to misinterpretation of the speech and makes it unsafe to rely on such communications. …


Transmitter Optimization In Multiuser Wireless Systems With Quality Of Service Constraints, Danda B. Rawat Jan 2010

Transmitter Optimization In Multiuser Wireless Systems With Quality Of Service Constraints, Danda B. Rawat

Electrical & Computer Engineering Theses & Dissertations

In this dissertation, transmitter adaptation for optimal resource allocation in wireless communication systems are investigated. First, a multiple access channel model is considered where many transmitters communicate with a single receiver. This scenario is a basic component of a. wireless network in which multiple users simultaneously access the resources of a wireless service provider. Adaptive algorithms for transmitter optimization to meet Quality-of-Service (QoS) requirements in a distributed manner are studied. Second, an interference channel model is considered where multiple interfering transmitter-receiver pairs co-exist such that a given transmitter communicates with its intended receiver in the presence of interference from other …


Security In Ad Hoc Networks And Pervasive Computing, Isaac Z. Wu, X.-Y. Li, M. Song, C.-M. Liu Jan 2010

Security In Ad Hoc Networks And Pervasive Computing, Isaac Z. Wu, X.-Y. Li, M. Song, C.-M. Liu

Electrical & Computer Engineering Faculty Publications

Pervasive computing is an exciting and blooming research field, in which innovative techniques and applications are continuously emerging and aim to provide ambient and personalized services to users with high quality. Ad hoc networks are wireless, self-organizing systems formed by cooperating nodes within communication range of each other that form temporary networks. Their topology is dynamic, decentralized, ever changing and the nodes may move around arbitrarily. The last few years have witnessed a wealth of research ideas on ad hoc networking that are moving rapidly into implemented standards. Technology under development for ad hoc networks and pervasive computing is making …


Fault-Tolerance And Recovery In Wireless Sensor Networks, Kevin M. Somervill Oct 2009

Fault-Tolerance And Recovery In Wireless Sensor Networks, Kevin M. Somervill

Electrical & Computer Engineering Theses & Dissertations

The topic of Wireless Sensor Networks (WSNs) has gained considerable attention in the research community due to the variety of applications and interesting challenges in developing and deploying such networks. The typical WSN is significantly energy constrained and often deployed in harsh or even hostile environments, resulting in sensor nodes that are prone to failure. Failing nodes alter the topology of the network resulting in segmented routing paths and lost messages, ultimately reducing network efficiency. These issues spur the desire to develop energy-efficient, Fault-Tolerant (FT) algorithms that enable the network to persist in spite of the failed nodes. This work …


Virtual Wired Transmission Scheme - A Novel Technique For Efficient Mobile Adhoc Networks, Manikya Vinay Rali Jul 2009

Virtual Wired Transmission Scheme - A Novel Technique For Efficient Mobile Adhoc Networks, Manikya Vinay Rali

Electrical & Computer Engineering Theses & Dissertations

This thesis proposes a method called virtual wired transmission scheme for ad hoc networks. The scheme is an efficient method to improve network performance parameters such as energy efficiency, capacity, interference, network throughput, etc. Performance parameters improvement can be done at different layers of the network architecture for mobile ad hoc networks. However most of the research efforts are concentrated on Physical, MAC and Network layers. In this thesis, a MAC protocol with a major MAC layer modification is proposed in combination with the usage of directional antennas, developing a novel method called virtual wired transmission scheme. In virtual wired …


A Simulation Study Of Convergence Speed For Distributed Codeword Adaptation Algorithms In Cdma Wireless Systems, Sahana Maharjan Jul 2009

A Simulation Study Of Convergence Speed For Distributed Codeword Adaptation Algorithms In Cdma Wireless Systems, Sahana Maharjan

Electrical & Computer Engineering Theses & Dissertations

In this thesis we present a side-by-side comparison of interference avoidance (IA) algorithms for distributed codeword adaptation in Code Division Multiple Access (CDMA) systems. In CDMA systems, the interference is determined by the values of the cross-correlation of codewords assigned to users, and various algorithms can be used for codeword optimization. The IA algorithms for codeword adaptation considered are the eigen-algorithm, the Minimum Mean Square Error (MMSE) update, and the adaptive IA algorithm, for which we investigate convergence speed using the extensive simulations of several uplink CDMA system scenarios. The results of this thesis were presented at the Fourth IEEE …


Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson Jun 2009

Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson

Computer Science Presentations

PDF of a powerpoint presentation from the 2009 ACM/IEEE Joint Conference on Digital Libraries, Austin, Texas, June 15-19, 2009. Also available on Slideshare.


Adding Escience Assets To The Data Web, Herbert H. Van De Sompel, Carl Lagoze, Michael L. Nelson, Simeon Warner, Robert Sanderson, Pete Johnston Apr 2009

Adding Escience Assets To The Data Web, Herbert H. Van De Sompel, Carl Lagoze, Michael L. Nelson, Simeon Warner, Robert Sanderson, Pete Johnston

Computer Science Faculty Publications

Aggregations of Web resources are increasingly important in scholarship as it adopts new methods that are data-centric, collaborative, and networked-based. The same notion of aggregations of resources is common to the mashed-up, socially networked information environment of Web 2.0. We present a mechanism to identify and describe aggregations of Web resources that has resulted from the Open Archives Initiative - Object Reuse and Exchange (OAI-ORE) project. The OAI-ORE specifications are based on the principles of the Architecture of the World Wide Web, the Semantic Web, and the Linked Data effort. Therefore, their incorporation into the cyberinfrastructure that supports eScholarship will …


A Hidden Markov Model Based Approach To Detect Rogue Access Points, Gayathri Shivaraj Apr 2009

A Hidden Markov Model Based Approach To Detect Rogue Access Points, Gayathri Shivaraj

Electrical & Computer Engineering Theses & Dissertations

One of the most challenging security concerns for network administrators is the presence of Rogue access points. The challenge is to detect and disable a Rogue access point before it can cause hazardous damage to the network. This thesis proposes a statistically based approach to detect Rogue access points using a Hidden Markov Model, which is applied to passively measure packet-header data collected at a gateway router or any monitoring point. This approach utilizes variations in packet inter-arrival time to differentiate between authorized access points and Rouge access points. This approach used the inter-arrival time of a packet as a …


A Hurricane Evacuation Route System Real-Time Monitoring And Distribution Of Load, Anup Khanal Apr 2009

A Hurricane Evacuation Route System Real-Time Monitoring And Distribution Of Load, Anup Khanal

Electrical & Computer Engineering Theses & Dissertations

Hurricane evacuation is one of the major steps in diminishing the devastating effects of hurricanes on lives and properties. The challenge in evacuating a large number of people in a short time is the severe congestion faced in the transportation network, leading to long delays and shortages. Standard hurricane evacuation plans focus on how to best utilize the main arteries. The research challenge is to not overload the fastest routes and to utilize all the routes efficiently. The evacuation routing system proposed in this thesis focuses on distributing the traffic load throughout the network, utilizing alternative routes not considered in …


Implementation Requirements For The Notice Architecture In Vehicular Communications, Dusadee Treeumnuk Apr 2009

Implementation Requirements For The Notice Architecture In Vehicular Communications, Dusadee Treeumnuk

Electrical & Computer Engineering Theses & Dissertations

Many studies have been focusing on Vehicular Ad-Hoc Networking (VANET) in order to increase the quality of traffic and life on the road. An important aspect in vehicular communications is maintaining the privacy and security of VANET. NOTICE is an emerging architecture promising efficient traffic notification as well as strong immunity to malicious attacks, leading to improvement of safety and reduction of traffic congestion on roadways. To enable secure traffic notification, the NOTICE system employs vehicle-to-infrastructure (V2I) communication rather than vehicle-to-vehicle (V2V) communication like in traditional VANET. The infrastructure consists of sensor belts which are embedded in the roadway and …


Supporting Protocols For Structuring And Intelligent Information Dissemination In Vehicular Ad Hoc Networks, Filip Cuckov Jan 2009

Supporting Protocols For Structuring And Intelligent Information Dissemination In Vehicular Ad Hoc Networks, Filip Cuckov

Electrical & Computer Engineering Theses & Dissertations

The goal of this dissertation is the presentation of supporting protocols for structuring and intelligent data dissemination in vehicular ad hoc networks (VANETs). The protocols are intended to first introduce a structure in VANETs, and thus promote the spatial reuse of network resources. Segmenting a flat VANET in multiple cluster structures allows for more efficient use of the available bandwidth, which can effectively increase the capacity of the network. The cluster structures can also improve the scalability of the underlying communication protocols. The structuring and maintenance of the network introduces additional overhead. The aim is to provide a mechanism for …


Multicast Encryption Infrastructure For Security In Sensor Networks, Richard R. Brooks, Brijesh Pillai, Matthew Pirretti, Michele C. Weigle Jan 2009

Multicast Encryption Infrastructure For Security In Sensor Networks, Richard R. Brooks, Brijesh Pillai, Matthew Pirretti, Michele C. Weigle

Computer Science Faculty Publications

Designing secure sensor networks is difficult. We propose an approach that uses multicast communications and requires fewer encryptions than pairwise communications. The network is partitioned into multicast regions; each region is managed by a sensor node chosen to act as a keyserver. The keyservers solicit nodes in their neighborhood to join the local multicast tree. The keyserver generates a binary tree of keys to maintain communication within the multicast region using a shared key. Our approach supports a distributed key agreement protocol that identifies the compromised keys and supports membership changes with minimum system overhead. We evaluate the overhead of …


High-Performance Broadcast And Multicast Protocols For Multi-Radio Multi-Channel Wireless Mesh Networks, Jun Wang Jan 2009

High-Performance Broadcast And Multicast Protocols For Multi-Radio Multi-Channel Wireless Mesh Networks, Jun Wang

Electrical & Computer Engineering Theses & Dissertations

Recently, wireless mesh networks (WMNs) have attracted much attention. A vast amount of unicast, multicast and broadcast protocols has been developed for WMNs or mobile ad hoc networks (MANETs). First of all, broadcast and multicast in wireless networks are fundamentally different from the way in which wired networks function due to the well-known wireless broadcast/multicast advantage. Moreover, most broadcast and multicast protocols in wireless networks assume a single-radio single-channel and single-rate network model, or a generalized physical model, which does not take into account the impact of interference. This dissertation focuses on high-performance broadcast and multicast protocols designed for multi-radio …


Biomarker Identification For Prostate Cancer Using An Efficient Feature Selection Algorithm, Vamsi Krishnam Raju Mantena Oct 2008

Biomarker Identification For Prostate Cancer Using An Efficient Feature Selection Algorithm, Vamsi Krishnam Raju Mantena

Electrical & Computer Engineering Theses & Dissertations

In recent years, there has been an increased interest in using protein mass spectrometry to identify biomarkers that discriminate diseased from healthy individuals. A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathological processes, or pharmacological responses to a therapeutic intervention. Identifying biomarkers will be an important step towards disease characterization and patient management. One challenge of biomarker identification is how to handle the high dimensional mass spectral data. In this thesis, we applied an efficient feature selection algorithm to mass spectrometry data obtained from prostate tissue samples to identify prostate …