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Theses and Dissertations

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Full-Text Articles in Computer Sciences

Flexible Storylines, Ivan Dmitrievich Romashka May 2011

Flexible Storylines, Ivan Dmitrievich Romashka

Theses and Dissertations

A long-standing goal of computer-based entertainment is the creation of a story where a user is in control of portions of the storyline. These non-linear stories give a user an opportunity to adapt the story to his or her interests, schedule and needs. The Internet has made non-linear video a reality. Different approaches have been taken to create and play non-linear video stories. They suffer from lack of simplicity, smoothness, and television-like experience in story creation and presentation. Flexible Storylines provide a way to easily create and present non-linear video stories. The creation of these stories is done using a …


Proofs Of Correctness For Three Decentralized Authentication Protocols Using Strand Spaces, Pavan Kumar Vankamamidi May 2011

Proofs Of Correctness For Three Decentralized Authentication Protocols Using Strand Spaces, Pavan Kumar Vankamamidi

Theses and Dissertations

Security is a major concern is today's online world. As online activities become increasingly sensitive, service providers rely on security protocols to ensure confidentiality, integrity and authentication of their users and data. Greater assurance is provided when these protocols are verified to be correct. Strand Spaces is a method to formally analyze security protocols. The arguments are based on the messages being transmitted and received while assuming that the underlying cryptographic primitives are secure. This thesis demonstrates that the protocols Luau, pwdArmor and Kiwi are secure using Strand Spaces methodology.


Social Capital In Online Communities, Matthew Scott Smith May 2011

Social Capital In Online Communities, Matthew Scott Smith

Theses and Dissertations

Social capital is the value of the relationships we create and maintain within our social networks to gain access to and mobilize needed resources (e.g., jobs, moral support). Quantifying, and subsequently leveraging, social capital are challenging problems in the social sciences. Most work so far has focused on analyses from static surveys of limited numbers of participants. The explosion of online social media means that it is now possible to collect rich data about people's connections and interactions, in a completely ubiquitous, non-intrusive manner. Such dynamic social data opens the door to the more accurate measuring and tracking of social …


Accelerated Large-Scale Multiple Sequence Alignment With Reconfigurable Computing, G Scott Lloyd May 2011

Accelerated Large-Scale Multiple Sequence Alignment With Reconfigurable Computing, G Scott Lloyd

Theses and Dissertations

Multiple Sequence Alignment (MSA) is a fundamental analysis method used in bioinformatics and many comparative genomic applications. The time to compute an optimal MSA grows exponentially with respect to the number of sequences. Consequently, producing timely results on large problems requires more efficient algorithms and the use of parallel computing resources. Reconfigurable computing hardware provides one approach to the acceleration of biological sequence alignment. Other acceleration methods typically encounter scaling problems that arise from the overhead of inter-process communication and from the lack of parallelism. Reconfigurable computing allows a greater scale of parallelism with many custom processing elements that have …


Computational Modeling Of Mulitsensory Processing Using Network Of Spiking Neurons, Hun Ki Lim May 2011

Computational Modeling Of Mulitsensory Processing Using Network Of Spiking Neurons, Hun Ki Lim

Theses and Dissertations

Multisensory processing in the brain underlies a wide variety of perceptual phenomena, but little is known about the underlying mechanisms of how multisensory neurons are generated and how the neurons integrate sensory information from environmental events. This lack of knowledge is due to the difficulty of biological experiments to manipulate and test the characteristics of multisensory processing. By using a computational model of multisensory processing this research seeks to provide insight into the mechanisms of multisensory processing. From a computational perspective, modeling of brain functions involves not only the computational model itself but also the conceptual definition of the brain …


Coherent Turbulence: Synthesizing Tree Motion In The Wind Using Cfd And Noise, Anthony Frank Selino May 2011

Coherent Turbulence: Synthesizing Tree Motion In The Wind Using Cfd And Noise, Anthony Frank Selino

Theses and Dissertations

Animating trees in wind has long been a problem in computer graphics. Progress on this problem is important for both visual effects and biomechanics and may inform future work on two-way coupling between turbulent flows and deformable objects. Synthetic turbulence added to a coarse fluid simulation has been used to produce convincing animations of turbulent flows, but only considers one-way coupling between fluid and solid. We produce accurate animations of tree motion by creating a two-way coupling between synthetic turbulence and semipermeable proxy geometry. The resulting animations exhibit global wind sheltering effects and branch tips have motion paths which match …


Processing And Classification Of Physiological Signals Using Wavelet Transform And Machine Learning Algorithms, Abed Al-Raoof Bsoul Apr 2011

Processing And Classification Of Physiological Signals Using Wavelet Transform And Machine Learning Algorithms, Abed Al-Raoof Bsoul

Theses and Dissertations

Over the last century, physiological signals have been broadly analyzed and processed not only to assess the function of the human physiology, but also to better diagnose illnesses or injuries and provide treatment options for patients. In particular, Electrocardiogram (ECG), blood pressure (BP) and impedance are among the most important biomedical signals processed and analyzed. The majority of studies that utilize these signals attempt to diagnose important irregularities such as arrhythmia or blood loss by processing one of these signals. However, the relationship between them is not yet fully studied using computational methods. Therefore, a system that extract and combine …


A Speculative Approach To Parallelization In Particle Swarm Optimization, Matthew J. Gardner Apr 2011

A Speculative Approach To Parallelization In Particle Swarm Optimization, Matthew J. Gardner

Theses and Dissertations

Particle swarm optimization (PSO) has previously been parallelized primarily by distributing the computation corresponding to particles across multiple processors. In this thesis we present a speculative approach to the parallelization of PSO that we refer to as SEPSO. In our approach, we refactor PSO such that the computation needed for iteration t+1 can be done concurrently with the computation needed for iteration t. Thus we can perform two iterations of PSO at once. Even with some amount of wasted computation, we show that this approach to parallelization in PSO often outperforms the standard parallelization of simply adding particles to the …


Outdoor Scenes For Data Visualization, Benjamin A. Hillery Apr 2011

Outdoor Scenes For Data Visualization, Benjamin A. Hillery

Theses and Dissertations

Recent cognitive research indicates that the human brain possesses special abilities for processing information relating to outdoor scenes. Simulated outdoor scenes are presented as an effective method of displaying higher dimensional data in an efficient and comprehensible manner. We demonstrate novel methods of using outdoor objects and scenes to display multidimensional content in a way that that is intuitive for humans to understand, and to exploit various cues commonly found in scenes from the natural world to communicate the values of multiple variables.


Real-Time Fundamental Frequency Estimation Algorithm For Disconnected Speech, Thomas Skjei Apr 2011

Real-Time Fundamental Frequency Estimation Algorithm For Disconnected Speech, Thomas Skjei

Theses and Dissertations

A new algorithm is presented for real-time fundamental frequency estimation of speech signals. This method extends and alters the YIN algorithm, which uses the autocorrelation-based difference function, by adding features to reduce latency, correct predictable errors, and make it structurally appropriate for real-time processing scenarios. The algorithm is shown to reduce the error rate of its predecessor while demonstrating latencies sufficient for real-time processing. The results indicate that the algorithm can be realized as a real-time estimator of spoken pitch and pitch variation, which has applications including diagnosis and biofeedback-based therapy of many speech disorders.


Easy To Find: Creating Query-Based Multi-Document Summaries To Enhance Web Search, Rani Majed Qumsiyeh Mar 2011

Easy To Find: Creating Query-Based Multi-Document Summaries To Enhance Web Search, Rani Majed Qumsiyeh

Theses and Dissertations

Current web search engines, such as Google, Yahoo!, and Bing, rank the set of documents S retrieved in response to a user query Q and display each document with a title and a snippet, which serves as an abstract of the corresponding document in S. Snippets, however, are not as useful as they are designed for, i.e., to assist search engine users to quickly identify results of interest, if they exist, without browsing through the documents in S, since they (i) often include very similar information and (ii) do not capture the main content of the corresponding documents. …


A Multi Agent System For Flow-Based Intrusion Detection Using Reputation And Evolutionary Computation, David Hancock Mar 2011

A Multi Agent System For Flow-Based Intrusion Detection Using Reputation And Evolutionary Computation, David Hancock

Theses and Dissertations

The rising sophistication of cyber threats as well as the improvement of physical computer network properties present increasing challenges to contemporary Intrusion Detection (ID) techniques. To respond to these challenges, a multi agent system (MAS) coupled with flow-based ID techniques may effectively complement traditional ID systems. This paper develops: 1) a scalable software architecture for a new, self-organized, multi agent, flow-based ID system; and 2) a network simulation environment suitable for evaluating implementations of this MAS architecture and for other research purposes. Self-organization is achieved via 1) a reputation system that influences agent mobility in the search for effective vantage …


Malicious And Malfunctioning Node Detection Via Observed Physical Layer Data, Tyler J. Hardy Mar 2011

Malicious And Malfunctioning Node Detection Via Observed Physical Layer Data, Tyler J. Hardy

Theses and Dissertations

There are many mechanisms that can cause inadequate or unreliable information in sensor networks. A user of the network might be interested in detecting and classifying specific sensors nodes causing these problems. Several network layer based trust methods have been developed in previous research to assess these issues; in contrast this work develops a trust protocol based on observations of physical layer data collected by the sensors. Observations of physical layer data are used for decisions and calculations, and are based on just the measurements collected by the sensors. Although this information is packaged and distributed on the network layer, …


Holistic Network Defense: Fusing Host And Network Features For Attack Classification, Jenny W. Ji Mar 2011

Holistic Network Defense: Fusing Host And Network Features For Attack Classification, Jenny W. Ji

Theses and Dissertations

This work presents a hybrid network-host monitoring strategy, which fuses data from both the network and the host to recognize malware infections. This work focuses on three categories: Normal, Scanning, and Infected. The network-host sensor fusion is accomplished by extracting 248 features from network traffic using the Fullstats Network Feature generator and from the host using text mining, looking at the frequency of the 500 most common strings and analyzing them as word vectors. Improvements to detection performance are made by synergistically fusing network features obtained from IP packet flows and host features, obtained from text mining port, processor, logon …


An Architecture For Improving Timeliness And Relevance Of Cyber Incident Notifications, James L. Miller Mar 2011

An Architecture For Improving Timeliness And Relevance Of Cyber Incident Notifications, James L. Miller

Theses and Dissertations

This research proposes a communications architecture to deliver timely and relevant cyber incident notifications to dependent mission stakeholders. This architecture, modeled in Unified Modeling Language (UML), eschews the traditional method of pushing notifications via message as dictated in Air Force Instruction 33-138. It instead shifts to a pull or publish and subscribe method of making notifications. Shifting this paradigm improves the notification process by empowering mission owners to identify those resources on which they depend for mission accomplishment, provides a direct conduit between providing and dependent mission owners for notifications when an incident occurs, and provides a shared representation for …


Evaluating Information Assurance Control Effectiveness On An Air Force Supervisory Control And Data Acquisition (Scada) System, Jason R. Nielsen Mar 2011

Evaluating Information Assurance Control Effectiveness On An Air Force Supervisory Control And Data Acquisition (Scada) System, Jason R. Nielsen

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems are increasingly being connected to corporate networks which has dramatically expanded their attack surface to remote cyber attack. Adversaries are targeting these systems with increasing frequency and sophistication. This thesis seeks to answer the research question addressing which Information Assurance (IA) controls are most significant for network defenders and SCADA system managers/operators to focus on in order to increase the security of critical infrastructure systems against a Stuxnet-like cyber attack. This research applies the National Institute of Science and Technology (NIST) IA controls to an attack tree modeled on a remote Stuxnet-like cyber …


Defensive Cyber Battle Damage Assessment Through Attack Methodology Modeling, Ryan T. Ostler Mar 2011

Defensive Cyber Battle Damage Assessment Through Attack Methodology Modeling, Ryan T. Ostler

Theses and Dissertations

Due to the growing sophisticated capabilities of advanced persistent cyber threats, it is necessary to understand and accurately assess cyber attack damage to digital assets. This thesis proposes a Defensive Cyber Battle Damage Assessment (DCBDA) process which utilizes the comprehensive understanding of all possible cyber attack methodologies captured in a Cyber Attack Methodology Exhaustive List (CAMEL). This research proposes CAMEL to provide detailed knowledge of cyber attack actions, methods, capabilities, forensic evidence and evidence collection methods. This product is modeled as an attack tree called the Cyber Attack Methodology Attack Tree (CAMAT). The proposed DCBDA process uses CAMAT to analyze …


Android Protection System: A Signed Code Security Mechanism For Smartphone Applications, Jonathan D. Stueckle Mar 2011

Android Protection System: A Signed Code Security Mechanism For Smartphone Applications, Jonathan D. Stueckle

Theses and Dissertations

This research develops the Android Protection System (APS), a hardware-implemented application security mechanism on Android smartphones. APS uses a hash-based white-list approach to protect mobile devices from unapproved application execution. Functional testing confirms this implementation allows approved content to execute on the mobile device while blocking unapproved content. Performance benchmarking shows system overhead during application installation increases linearly as the application package size increases. APS presents no noticeable performance degradation during application execution. The security mechanism degrades system performance only during application installation, when users expect delay. APS is implemented within the default Android application installation process. Applications are hashed …


Spear Phishing Attack Detection, David T. Merritt Mar 2011

Spear Phishing Attack Detection, David T. Merritt

Theses and Dissertations

This thesis addresses the problem of identifying email spear phishing attacks, which are indicative of cyber espionage. Spear phishing consists of targeted emails sent to entice a victim to open a malicious file attachment or click on a malicious link that leads to a compromise of their computer. Current detection methods fail to detect emails of this kind consistently. The SPEar phishing Attack Detection system (SPEAD) is developed to analyze all incoming emails on a network for the presence of spear phishing attacks. SPEAD analyzes the following file types: Windows Portable Executable and Common Object File Format (PE/COFF), Adobe Reader, …


Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert Mar 2011

Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert

Theses and Dissertations

Side Channel Analysis (SCA) is a method by which an adversary can gather information about a processor by examining the activity being done on a microchip though the environment surrounding the chip. Side Channel Analysis attacks use SCA to attack a microcontroller when it is processing cryptographic code, and can allow an attacker to gain secret information, like a crypto-algorithm's key. The purpose of this thesis is to test proposed dynamic hardware methods to increase the hardware security of a microprocessor such that the software code being run on the microprocessor can be made more secure without having to change …


Kernelized Locality-Sensitive Hashing For Fast Image Landmark Association, Mark A. Weems Mar 2011

Kernelized Locality-Sensitive Hashing For Fast Image Landmark Association, Mark A. Weems

Theses and Dissertations

As the concept of war has evolved, navigation in urban environments where GPS may be degraded is increasingly becoming more important. Two existing solutions are vision-aided navigation and vision-based Simultaneous Localization and Mapping (SLAM). The problem, however, is that vision-based navigation techniques can require excessive amounts of memory and increased computational complexity resulting in a decrease in speed. This research focuses on techniques to improve such issues by speeding up and optimizing the data association process in vision-based SLAM. Specifically, this work studies the current methods that algorithms use to associate a current robot pose to that of one previously …


Measuring The Utility Of A Cyber Incident Mission Impact Assessment (Cimia) Process For Mission Assurance, Christy L. Peterson Mar 2011

Measuring The Utility Of A Cyber Incident Mission Impact Assessment (Cimia) Process For Mission Assurance, Christy L. Peterson

Theses and Dissertations

Information is a critical asset on which virtually all modern organizations depend upon to meet their operational mission objectives. Military organizations, in particular, have embedded Information and Communications Technologies (ICT) into their core mission processes as a means to increase their operational efficiency, exploit automation, improve decision quality, and shorten the kill chain. However, the extreme dependence upon ICT results in an environment where a cyber incident can result in severe mission degradation, or possibly failure, with catastrophic consequences to life, limb, and property. These consequences can be minimized by maintaining real-time situational awareness of mission critical resources so appropriate …


Advances In Software Engineering, Alban Krasniqi Mar 2011

Advances In Software Engineering, Alban Krasniqi

Theses and Dissertations

Inxhinieria Softuerike është aplikimi i një qasje sistematike të disiplinuar, të matshme për zhvillimin, operimin dhe mirëmbajtjen e softuerit. Për rreth çdo aktivitet është një strukturë komplekse të cilat janë të mbështetura dhe të lidhura me aktivitetet dhe shqetësimet ekonomike, organizative, menaxheriale dhe një strukture komplekse të kufizuar. Ne ketë punim jemi munduar qe ti trajtojmë disa tema qe i gjejmë të trajtuara rrallë neper literaturat qe ofrohen sot ne fushën e inxhinierisë softuerike . Duke pas parasysh se Inxhinieria Softuerike përfshin një diapazon të gjere mirëpo nder pozitat me kryesore është ajo e menaxhimit te projekteve ne me ane …


Advanced I/O Techniques For Efficient And Highly Available Process Crash Recovery Protocols, Jason Warren Cornwell Mar 2011

Advanced I/O Techniques For Efficient And Highly Available Process Crash Recovery Protocols, Jason Warren Cornwell

Theses and Dissertations

As the number of CPU cores in high-performance computing platforms continues to grow, the availability and reliability of these systems become a primary concern. As such, some solutions are physical (ie. power backup) and some are software driven. Lawrence Berkeley National Laboratory has created a system-level fault-tolerant checkpoint/restart implementation for Linux Clusters. This allows processes to restart computations at the last known checkpoint in the event the system crashes. The checkpoint data creation is highly dependent on system input and output operations. This paper proposes: (i) a technique to improve the efficiency of these I/O operations and (ii) an alternative …


Programming Language Fragmentation And Developer Productivity: An Empirical Study, Jonathan L. Krein Feb 2011

Programming Language Fragmentation And Developer Productivity: An Empirical Study, Jonathan L. Krein

Theses and Dissertations

In an effort to increase both the quality of software applications and the efficiency with which applications can be written, developers often incorporate multiple programming languages into software projects. Although language specialization arguably introduces benefits, the total impact of the resulting language fragmentation (working concurrently in multiple programming languages) on developer performance is unclear. For instance, developers may solve problems more efficiently when they have multiple language paradigms at their disposal. However, the overhead of maintaining efficiency in more than one language may outweigh those benefits. This thesis represents a first step toward understanding the relationship between language fragmentation and …


Relationships Among Learning Algorithms And Tasks, Jun Won Lee Jan 2011

Relationships Among Learning Algorithms And Tasks, Jun Won Lee

Theses and Dissertations

Metalearning aims to obtain knowledge of the relationship between the mechanism of learning and the concrete contexts in which that mechanisms is applicable. As new mechanisms of learning are continually added to the pool of learning algorithms, the chances of encountering behavior similarity among algorithms are increased. Understanding the relationships among algorithms and the interactions between algorithms and tasks help to narrow down the space of algorithms to search for a given learning task. In addition, this process helps to disclose factors contributing to the similar behavior of different algorithms. We first study general characteristics of learning tasks and their …


Parallel Particle Swarm Optimization And Large Swarms, Andrew W. Mcnabb Jan 2011

Parallel Particle Swarm Optimization And Large Swarms, Andrew W. Mcnabb

Theses and Dissertations

Optimization is the search for the maximum or minimum of a given objective function. Particle Swarm Optimization (PSO) is a simple and effective evolutionary algorithm, but it may take hours or days to optimize difficult objective functions which are deceptive or expensive. Deceptive functions may be highly multimodal and multidimensional, and PSO requires extensive exploration to avoid being trapped in local optima. Expensive functions, whose computational complexity may arise from dependence on detailed simulations or large datasets, take a long time to evaluate. For deceptive or expensive objective functions, PSO must be parallelized to use multiprocessor systems and clusters efficiently. …


A Reusable Persistence Framework For Replicating Empirical Studies On Data From Open Source Repositories, Scott Bong-Soo Chun Dec 2010

A Reusable Persistence Framework For Replicating Empirical Studies On Data From Open Source Repositories, Scott Bong-Soo Chun

Theses and Dissertations

Empirical research is inexact and error-prone leading researchers to agree that replication of experiments is a necessary step to validating empirical results. Unfortunately, replicating experiments requires substantial investments in manpower and time. These resource requirements can be reduced by incorporating component reuse when building tools for empirical experimentation. Bokeo is an initiative within the Sequoia Lab of the BYU Computer Science Department to develop a platform to assist in the empirical study of software engineering. The i3Persistence Framework is a component of Bokeo which enables researchers to easily build and rapidly deploy tools for empirical experiments by providing an easy-to-use …


Capture And Access Of Multiple Screen Presentations, Kelv H. Cutler Dec 2010

Capture And Access Of Multiple Screen Presentations, Kelv H. Cutler

Theses and Dissertations

Knowledge transferred during meetings is often ephemeral in nature and thus must be captured if it is to be retained. Ideally, a capture solution should be able to 1) accommodate any number of screens without sacrificing image quality and 2) allow dynamic access to a complete media capture while the capture is taking place. Both students and employees can benefit from the information captured during the lectures and meetings for enhanced discussion and afterward for knowledge retention. Current systems do not support multiple screen capture well, and no system supports dynamic access to the active meeting capture during the meeting. …


Trusted Mobile Overlays, Robert Scott Robertson Dec 2010

Trusted Mobile Overlays, Robert Scott Robertson

Theses and Dissertations

Sensitive information is increasingly moving online and as data moves further from the control of its owner, there are increased opportunities for it to fall into malicious hands. The Web is comprised of three untrusted components where there is a risk of information compromise: networks, service providers, and clients. This thesis presents Trusted Mobile Overlays: a system that leverages trusted mobile devices to protect users from these untrusted components of the Web, while minimizing deployment difficulties. It presents a high-level design of the system as well as a prototype that implements the design.