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Theses and Dissertations

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Full-Text Articles in Computer Sciences

Utilizing The Digital Fingerprint Method For Secure Key Generation, Jennifer C. Anilao Mar 2010

Utilizing The Digital Fingerprint Method For Secure Key Generation, Jennifer C. Anilao

Theses and Dissertations

This research examines a new way to generate an uncloneable secure key by taking advantage of the delay characteristics of individual transistors. The user profiles the circuit to deduce the glitch count of each output line for each number of selectable buffers added to the circuit. The user can then use this information to generate a specific glitch count on each output line, which is passed to an encryption algorithm as its key. The results detail tests of two configurations for adding a selectable amount of buffers into each glitch circuit in order to induce additional delay. One configuration adds …

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Performance Of Scattering Matrix Decomposition And Color Spaces For Synthetic Aperture Radar Imagery, Manuel E. Arriagada Mar 2010

Performance Of Scattering Matrix Decomposition And Color Spaces For Synthetic Aperture Radar Imagery, Manuel E. Arriagada

Theses and Dissertations

Polarimetrc Synthetic Aperture Radar (SAR) has been shown to be a powerful tool in remote sensing because uses up to four simultaneous measurements giving additional degrees of freedom for processing. Typically, polarization decomposition techniques are applied to the polarization-dependent data to form colorful imagery that is easy for operators systems to interpret. Yet, the presumption is that the SAR system operates with maximum bandwidth which requires extensive processing for near- or real-time application. In this research, color space selection is investigated when processing sparse polarimetric SAR data as in the case of the publicly available \Gotcha Volumetric SAR Data Set, …

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Frequency Diverse Array Radar: Signal Characterization And Measurement Accuracy, Steven H. Brady Mar 2010

Frequency Diverse Array Radar: Signal Characterization And Measurement Accuracy, Steven H. Brady

Theses and Dissertations

Radar systems provide an important remote sensing capability, and are crucial to the layered sensing vision; a concept of operation that aims to apply the right number of the right types of sensors, in the right places, at the right times for superior battle space situational awareness. The layered sensing vision poses a range of technical challenges, including radar, that are yet to be addressed. To address the radar-specific design challenges, the research community responded with waveform diversity; a relatively new field of study which aims reduce the cost of remote sensing while improving performance. Early work suggests that the …

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Interactive Television News, Derek L. Bunn Mar 2010

Interactive Television News, Derek L. Bunn

Theses and Dissertations

We design and evaluate a way to modify television news to make it interactive for viewers. We allow them to get more of what they want and less of what they don't want. This allows news to break constraints imposed by television broadcast schedules. Our solution is to augment the existing news broadcast structure in the following ways: add a video headlines menu, provide on-demand access to additional story content, provide interactive navigation controls between stories, and a control overlay. For news producers we create a video annotation program and process to help create the interactive news. We use the …

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Automated Measurement Of Midline Shift In Brain Ct Images And Its Application In Computer-Aided Medical Decision Making, Chen Wenan Mar 2010

Automated Measurement Of Midline Shift In Brain Ct Images And Its Application In Computer-Aided Medical Decision Making, Chen Wenan

Theses and Dissertations

The severity of traumatic brain injury (TBI) is known to be characterized by the shift of the middle line in brain as the ventricular system often changes in size and position, depending on the location of the original injury. In this thesis, the focus is given to processing of the CT (Computer Tomography) brain images to automatically calculate midline shift in pathological cases and use it to predict Intracranial Pressure (ICP). The midline shift measurement can be divided into three steps. First the ideal midline of the brain, i.e., the midline before injury, is found via a hierarchical search based …

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Studying The Performance Of Wireless Mesh Networks Using The Hxh Transport Control Protocol, Timothy Scott Larsen Feb 2010

Studying The Performance Of Wireless Mesh Networks Using The Hxh Transport Control Protocol, Timothy Scott Larsen

Theses and Dissertations

As the need to remain connected increases, more and more people are turning to wireless mesh networks because they reduce the need for network infrastructure. Unfortunately, TCP does not perform well in such networks. HxH, an alternate protocol, has shown great promise in simulations, but since it relies on exploiting passive feedback, real measurements are needed to determine how effective the protocol really is. This thesis uses a measurement study on a wireless mesh network to characterize the performance of the HxH protocol in real-world networks. Several aspects of the HxH protocol do in fact perform well on real networks, …

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Graph-Based Global Illumination, Brian C. Ricks Jan 2010

Graph-Based Global Illumination, Brian C. Ricks

Theses and Dissertations

The slow render times of global illumination algorithms make them impractical in most commercial and academic settings. We propose a novel framework for calculating the computational complexity of global illumination algorithms and show that no other recent improvements have reduced this complexity. We further show that many algorithms use a tree as their rendering paradigm. We propose a new rendering algorithm, pipe casting, which calculates light paths using a graph instead of a tree. Pipe casting significantly reduces both computational complexity and actual render time of rendering. Using an L2 pixel-wise error comparison, on average our algorithm can render a …

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Hybrid Matching And Risk Assessment Of The Misspelled Names Hmra, Cihan Varol Dec 2009

Hybrid Matching And Risk Assessment Of The Misspelled Names Hmra, Cihan Varol

Theses and Dissertations

Companies acquire personal information from phone, World Wide Web, or email in order to sell or send an advertisement about their product. However, when this information is acquired, moved, copied or edited, the data may loose its quality. Often, the use of data administrators or a tool that has limited capabilities to correct the mistyped information can cause many problems. Moreover, most of the correction techniques are particularly implemented for the words used in daily conversations. Since personal names have different characteristics compared to general text, firstly, we proposed a hybrid matching algorithm (PNRS) which employs phonetic encoding, string matching …

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Real Time Network Monitoring And Reporting System, Ricky Lee Massengale Sr. Dec 2009

Real Time Network Monitoring And Reporting System, Ricky Lee Massengale Sr.

Theses and Dissertations

With the ability of modern system developers to develop intelligent programs that allows machines to learn, modify and evolve themselves, current trends of reactionary methods to detect and eradicate malicious software code from infected machines is proving to be too costly. Addressing malicious software after an attack is the current methodology and should be a fallback approach. A modern approach should be to perpetually monitor the "enterprise network backbone" traffic and broadcast alerts while taking protective and pre-emptive measures, in the event that the traffic falls out of the bounds of pre-described norms. This work demonstrates that a synergy approach …

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Large-Scale Distributed Coalition Formation, Daniel R. Karrels Dec 2009

Large-Scale Distributed Coalition Formation, Daniel R. Karrels

Theses and Dissertations

The CyberCraft project is an effort to construct a large scale Distributed Multi-Agent System (DMAS) to provide autonomous Cyberspace defense and mission assurance for the DoD. It employs a small but flexible agent structure that is dynamically reconfigurable to accommodate new tasks and policies. This document describes research into developing protocols and algorithms to ensure continued mission execution in a system of one million or more agents, focusing on protocols for coalition formation and Command and Control. It begins by building large-scale routing algorithms for a Hierarchical Peer to Peer structured overlay network, called Resource-Clustered Chord (RC-Chord). RC-Chord introduces the …

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Interactive Football Summarization, Brandon B. Moon Dec 2009

Interactive Football Summarization, Brandon B. Moon

Theses and Dissertations

Football fans do not have the time to watch every game in its entirety and need an effective solution that summarizes them the story of the game. Human-generated summaries are often too short, requiring time and resources to create. We utilize the advantages of Interactive TV to create an automatic football summarization service that is cohesive, provides context, covers the necessary plays, and is concise. First, we construct a degree of interest function that ranks each play based on detailed, play-by-play game events as well as viewing statistics collected from an interactive viewing environment. This allows us to select the …

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Bisecting Document Clustering Using Model-Based Methods, Aaron Samuel Davis Dec 2009

Bisecting Document Clustering Using Model-Based Methods, Aaron Samuel Davis

Theses and Dissertations

We all have access to large collections of digital text documents, which are useful only if we can make sense of them all and distill important information from them. Good document clustering algorithms that organize such information automatically in meaningful ways can make a difference in how effective we are at using that information. In this paper we use model-based document clustering algorithms as a base for bisecting methods in order to identify increasingly cohesive clusters from larger, more diverse clusters. We specifically use the EM algorithm and Gibbs Sampling on a mixture of multinomials as the base clustering algorithms …

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Noninvasive Estimation Of Pulmonary Artery Pressure Using Heart Sound Analysis, Aaron W. Dennis Dec 2009

Noninvasive Estimation Of Pulmonary Artery Pressure Using Heart Sound Analysis, Aaron W. Dennis

Theses and Dissertations

Right-heart catheterization is the most accurate method for estimating pulmonary artery pressure (PAP). Because it is an invasive procedure it is expensive, exposes patients to the risk of infection, and is not suited for long-term monitoring situations. Medical researchers have shown that PAP influences the characteristics of heart sounds. This suggests that heart sound analysis is a potential noninvasive solution to the PAP estimation problem. This thesis describes the development of a prototype system, called PAPEr, which estimates PAP noninvasively using heart sound analysis. PAPEr uses patient data with machine learning algorithms to build models of how PAP affects heart …

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Warning Based Browser Extension To Protect User Data Against Phishing Attacks, Sree Rama Konduri Dec 2009

Warning Based Browser Extension To Protect User Data Against Phishing Attacks, Sree Rama Konduri

Theses and Dissertations

There are currently many anti-phishing tools to combat against the phishing and web scams. Many of which are browser extensions that warn users when they are using suspected phishing websites. But most of the users are ignoring the warnings of the phishing site and providing their valuable credentials. Therefore, the focus of this research is to develop a browser extension, which manipulates the user credentials, whenever a user ignores anti-phishing tools warnings about malicious websites. This browser extension will protect user's information from being handed to attackers.

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Statistical Tools For Linking Engine-Generated Malware To Its Engine, Edna Chelangat Milgo Dec 2009

Statistical Tools For Linking Engine-Generated Malware To Its Engine, Edna Chelangat Milgo

Theses and Dissertations

Malware-generating engines challenge typical malware analysts by requiring them to quickly extract and upload to their customers' machines, a signature for each of a possibly vast number of never-before-seen malware instances that an engine can generate in a short amount of time In this thesis we propose and evaluate two methods for linking variants of engine-generated malware to its engine. The proposed methods use the w-gram frequency vector (NFV) of the opcode mnemonics of an engine-generated malware in- stance as a feature vector for the instance. An NFV is a tuple that maps «-grams with their frequencies. The in-formation contained …

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Open Access Fiber To The Home Networking, Roger E. Timmerman Dec 2009

Open Access Fiber To The Home Networking, Roger E. Timmerman

Theses and Dissertations

The concept of open-access networks appeals to communities that want to invest in and improve their access to modern telecommunications services. By investing in, or building their own open-access telecommunications networks, communities can create an environment where several telecommunications service providers can co-exist on a common open-access infrastructure. This model promotes innovation and competition among several smaller service providers rather than having a monopoly or oligopoly from those companies that can afford the investment of infrastructure in the community. This research provides an analysis of two large open-access fiber-to-the-home networks in Utah to determine a set of recommendations and best-practices …

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Using Operator Teams For Supervisory Control, Jonathan M. Whetten Nov 2009

Using Operator Teams For Supervisory Control, Jonathan M. Whetten

Theses and Dissertations

Robots and other automated systems have potential use in many different fields. As the scope of robot applications that robots are used for increases, there is a growing desire to have human operators manage multiple robots. Typical methods of enabling operators to multi-task in this way involve some combination of user interfaces that support human cognition and advanced robot autonomy. Our research explores a complementary method of managing multiple robots by utilizing operator teams. The evidence suggests that for appropriate task scenarios, two cooperating operators can be more than twice as effective as one operator working alone.

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An Empirical Study Of Instance Hardness, Michael Reed Smith Nov 2009

An Empirical Study Of Instance Hardness, Michael Reed Smith

Theses and Dissertations

Most widely accepted measures of performance for learning algorithms, such as accuracy and area under the ROC curve, provide information about behavior at the data set level. They say nothing about which instances are misclassified, whether two learning algorithms with the same classification accuracy on a data set misclassify the same instances, or whether there are instances misclassified by all learning algorithms. These questions about behavior at the instance level motivate our empirical analysis of instance hardness, a measure of expected classification accuracy for an instance. We analyze the classification of 57 data sets using 9 learning algorithms. Of …

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An Online Credential Repository For Role-Based Delegation, Guangxu Zhou Zhou Nov 2009

An Online Credential Repository For Role-Based Delegation, Guangxu Zhou Zhou

Theses and Dissertations

In large scaled organizations deployed with Role-based Access Control, it is desired to have role delegation services within the domain of the corporation. But there is no widely accepted delegation model yet due to the complicated properties of authorization. The delegation model needs to bridge resources, policies, owners and users perfectly which demands more dimensions to be managed than the authentication process conducts. In this research work, we are proposing a prototype that enables delegation service for group users communicating with multicasting channels, the Role-based Access Control applied for both the communications and the user credentials of authorization. We combined …

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Feature-Based Interactive Terrain Sketching, Daniel B. Adams Nov 2009

Feature-Based Interactive Terrain Sketching, Daniel B. Adams

Theses and Dissertations

Procedural generation techniques are able to quickly and cheaply produce large areas of terrain. However, these techniques produce results that are not easily directable and often require artists to edit the results by hand to achieve the desired layout. This paper proposes a sketch-based system for controlling fractal terrain that allows for a wide variety of terrain feature types. Artists sketch features rather than constrained points or elevations. The system is interactive, provides quick on-demand previews of the terrain, and allows for iterative design modifications. Interaction between features is handled in a realistic fashion. An arbitrary vertex insertion order midpoint …

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Guided Testing For Automatic Error Discovery In Concurrent Software, Neha Shyam Rungta Sep 2009

Guided Testing For Automatic Error Discovery In Concurrent Software, Neha Shyam Rungta

Theses and Dissertations

The quality and reliability of software systems, in terms of their functional correctness, critically relies on the effectiveness of the testing tools and techniques to detect errors in the system before deployment. A lack of testing tools for concurrent programs that systematically control thread scheduling choices has not allowed concurrent software development to keep abreast with hardware trends of multi-core and multi-processor technologies. This motivates a need for the development of systematic testing techniques that detect errors in concurrent programs. The work in this dissertation presents a potentially scalable technique that can be used to detect concurrency errors in production …

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Application Of Dual-Tree Complex Wavelet Transforms To Burst Detection And Rf Fingerprint Classification, Randall W. Klein Aug 2009

Application Of Dual-Tree Complex Wavelet Transforms To Burst Detection And Rf Fingerprint Classification, Randall W. Klein

Theses and Dissertations

This work addresses various Open Systems Interconnection (OSI) Physical (PHY) layer mechanisms to extract and exploit RF waveform features (”fingerprints”) that are inherently unique to specific devices and that may be used to provide hardware specific identification (manufacturer, model, and/or serial number). This is addressed by applying a Dual-Tree Complex Wavelet Transform (DT-CWT) to improve burst detection and RF fingerprint classification. A ”Denoised VT” technique is introduced to improve performance at lower SNRs, with denoising implemented using a DT-CWT decomposition prior to Traditional VT processing. A newly developed Wavelet Domain (WD) fingerprinting technique is presented using statistical WD fingerprints with …

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Kiwivault: Encryption Software For Portable Storage Devices, Trevor Bradshaw Florence Aug 2009

Kiwivault: Encryption Software For Portable Storage Devices, Trevor Bradshaw Florence

Theses and Dissertations

While many people use USB flash drives, most do not protect their stored documents. Solutions for protecting flash drives exist but inherently limit functionality found in unprotected drives such as portability, usability, and the ability to share documents between multiple people. In addition, other drawbacks are introduced such as the possibility of losing access to protected documents if a password is lost. Assuming protecting portable documents is important, in order for people to be willing to protect their documents they should be required to make as few sacrifices in functionality as possible. We introduce KiwiVault, a USB flash drive encryption …

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Supporting Remote Manipulation: An Ecological Approach, John A. Atherton Aug 2009

Supporting Remote Manipulation: An Ecological Approach, John A. Atherton

Theses and Dissertations

User interfaces for remote robotic manipulation widely lack sufficient support for situation awareness and, consequently, can induce high mental workload. With poor situation awareness, operators may fail to notice task-relevant features in the environment often leading the robot to collide with the environment. With high workload, operators may not perform well over long periods of time and may feel stressed. We present an ecological visualization that improves operator situation awareness. Our user study shows that operators using the ecological interface collided with the environment on average half as many times compared with a typical interface, even with a poorly calibrated …

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A Hop-By-Hop Architecture For Multicast Transport In Ad Hoc Wireless Networks, Manoj Kumar Pandey Jul 2009

A Hop-By-Hop Architecture For Multicast Transport In Ad Hoc Wireless Networks, Manoj Kumar Pandey

Theses and Dissertations

Ad hoc wireless networks are increasingly being used to provide connectivity where a wired networking infrastructure is either unavailable or inaccessible. Many deployments utilize group communication, where several senders communicate with several receivers; multicasting has long been seen as an efficient way to provide this service. While there has been a great deal of research on multicast routing in ad hoc networks, relatively little attention has been paid to the design of multicast transport protocols, which provide reliability and congestion control. In this dissertation we design and implement a complete multicast transport architecture that includes both routing and transport protocols. …

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Musical Query-By-Content Using Self-Organizing Maps, Kyle B. Dickerson Jul 2009

Musical Query-By-Content Using Self-Organizing Maps, Kyle B. Dickerson

Theses and Dissertations

The ever-increasing density of computer storage devices has allowed the average user to store enormous quantities of multimedia content, and a large amount of this content is usually music. Current search techniques for musical content rely on meta-data tags which describe artist, album, year, genre, etc. Query-by-content systems, however, allow users to search based upon the actual acoustical content of the songs. Recent systems have mainly depended upon textual representations of the queries and targets in order to apply common string-matching algorithms and are often confined to a single query style (e.g., humming). These methods also lose much of the …

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Finding Alternatives To The Hard Disk Drive For Virtual Memory, Bruce Albert Embry Jul 2009

Finding Alternatives To The Hard Disk Drive For Virtual Memory, Bruce Albert Embry

Theses and Dissertations

Current computer systems fill the demand of operating systems and applications for ever greater amounts of random access memory by paging the least recently used data to the hard disk drive. This paging process is called "virtual memory," to indicate that the hard disk drive is used to create the illusion that the computer has more random access memory than it actually has. Unfortunately, the fastest hard disk drives are over five orders of magnitude slower than the DRAM they are emulating. When the demand for memory increases to the point that processes are being continually saved to disk and …

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Radio Determination On Mini-Uav Platforms: Tracking And Locating Radio Transmitters, Braden Russell Huber Jun 2009

Radio Determination On Mini-Uav Platforms: Tracking And Locating Radio Transmitters, Braden Russell Huber

Theses and Dissertations

Aircraft in the US are equipped with Emergency Locator Transmitters (ELTs). In emergency situations these beacons are activated, providing a radio signal that can be used to locate the aircraft. Recent developments in UAV technologies have enabled mini-UAVs (5-foot wingspan) to possess a high level of autonomy. Due to the small size of these aircraft they are human-packable and can be easily transported and deployed in the field. Using a custom-built Radio Direction Finder, we gathered readings from a known transmitter and used them to compare various Bayesian reasoning-based filtering algorithms. Using a custom-developed simulator, we were able to test …

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A Functional Framework For Content Management, Robert Emer Broadbent Jun 2009

A Functional Framework For Content Management, Robert Emer Broadbent

Theses and Dissertations

This thesis proposes a functional framework for content management. This framework provides concepts and vocabulary for analysis and description of content management systems. The framework is derived from an analysis of eight content management systems. It describes forty-five conceptual functions organized into five functional groups. The functionality derived from the analysis of the content management systems is described using the vocabulary provided by the functional framework. Coverage of the concepts in the existing systems is verified. The utility of the framework is validated through the creation of a prototype that implements sufficient functionality to support a set of specific use …

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An Efficient And Effective Implementation Of The Trust System For Power Grid Compartmentalization, Juan M. Carlos Gonzalez Jun 2009

An Efficient And Effective Implementation Of The Trust System For Power Grid Compartmentalization, Juan M. Carlos Gonzalez

Theses and Dissertations

As utility companies develop and incorporate new technologies, such as moving to utility Internet technology based architecture and standard; it is crucial that we do so with history in mind. We know that traditional utility protection and control systems were not designed with security in their top priorities. This presents a danger in an environment where near real-time responses are required to ensure safe operations. As a consequence, system security becomes a burden to the system rather than necessary protection. Unfortunately, technology implementation is not the only concern. The number of utility privately-owned companies has multiplied as the market has …

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