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Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer Dec 2006

Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer

Theses and Dissertations

In a world full of digital information we should be able to easily collect, organize, annotate, and leverage information from many different sources. This should be easy to do and not interrupt our normal workflow. A system to support information collection and organization should be user-friendly and as unobtrusive as possible, while still allowing for flexible and intelligent annotation. It should also be able to leverage the inherent information content of a collection of annotated information. We present a system that will demonstrate how these ideas can come together to make information collection easier and more productive. The system facilitates …


Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson Dec 2006

Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson

Theses and Dissertations

The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris …


Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen Dec 2006

Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen

Theses and Dissertations

Given a sentence, a paraphrase generation system produces a sentence that says the same thing but usually in a different way. The paraphrase generation problem can be formulated in the machine translation paradigm; instead of translation of English to a foreign language, the system translates an English sentence (for example) to another English sentence. Quirk et al. (2004) demonstrated this approach to generate almost 90% acceptable paraphrases. However, most of the sentences had little variation from the original input sentence. Leveraging syntactic information, this thesis project presents an approach that successfully generated more varied paraphrase sentences than the approach of …


Contour Encoded Compression And Transmission, Christopher B. Nelson Nov 2006

Contour Encoded Compression And Transmission, Christopher B. Nelson

Theses and Dissertations

As the need for digital libraries, especially genealogical libraries, continues to rise, the need for efficient document image compression is becoming more and more apparent. In addition, because many digital library users access them from dial-up Internet connections, efficient strategies for compression and progressive transmission become essential to facilitate browsing operations. To meet this need, we developed a novel method for representing document images in a parametric form. Like other “hybrid" image compression operations, the Contour Encoded Compression and Transmission (CECAT) system first divides images into foreground and background layers. The emphasis of this thesis revolves around improving the compression …


A Performance Evaluation Of Dynamic Transport Switching For Multi-Transport Devices, Lei Wang Nov 2006

A Performance Evaluation Of Dynamic Transport Switching For Multi-Transport Devices, Lei Wang

Theses and Dissertations

Multi-transport devices are becoming more common, but sophisticated software is needed to fully realize the advantages of these devices. In this paper, we examine the performance of dynamic transport switching, which selects the best available transport for communication between two devices. We simulate transport switching within the Quality of Transport (QoT) architecture and show that it can effectively mitigate the effects of congestion and interference for connections between two multi-transport devices. We then evaluate dynamic transport switching overhead to characterize its effect on application throughput. Based on these insights, we identify several limitations of the QoT architecture and present solutions …


On-Line Electronic Document Collaboration And Annotation, Trev R. Harmon Nov 2006

On-Line Electronic Document Collaboration And Annotation, Trev R. Harmon

Theses and Dissertations

The Internet provides a powerful medium for communication and collaboration. The ability one has to connect and interact with web-based tools from anywhere in the world makes the Internet ideal for such tasks. However, the lack of native tools can be a hindrance when deploying collaborative initiatives, as many current projects require specialized software in order to operate. This thesis demonstrates, with the comparably recent advances in browser technology and Document Object Model (DOM) implementation, a web-based collaborative annotation system can be developed that can be accessed by a user through a standards-compliant web browser. Such a system, demonstrated to …


Digital Receipts: A System To Detect The Compromise Of Digital Certificates, Nathaniel Allen Seeley Nov 2006

Digital Receipts: A System To Detect The Compromise Of Digital Certificates, Nathaniel Allen Seeley

Theses and Dissertations

The ease of copying digital materials creates difficulty in detecting the theft of digital certificates. Uneducated users frequently fail to protect their digital certificate keys by not encrypting them, storing them in insecure places, and using them unwisely. In addition, there is no way to prove that protocols involving certificates are completely secure. This thesis introduces a system to ameliorate these problems by detecting the compromise of digital certificates. It leverages dual logging messages sent via side channels to a trusted third party. This third party correlates these messages and automatically detects when an imposter presents a certificate based on …


Learning In Short-Time Horizons With Measurable Costs, Patrick Bowen Mullen Nov 2006

Learning In Short-Time Horizons With Measurable Costs, Patrick Bowen Mullen

Theses and Dissertations

Dynamic pricing is a difficult problem for machine learning. The environment is noisy, dynamic and has a measurable cost associated with exploration that necessitates that learning be done in short-time horizons. These short-time horizons force the learning algorithms to make pricing decisions based on scarce data. In this work, various machine learning algorithms are compared in the context of dynamic pricing. These algorithms include the Kalman filter, artificial neural networks, particle swarm optimization and genetic algorithms. The majority of these algorithms have been modified to handle the pricing problem. The results show that these adaptations allow the learning algorithms to …


Improving Error Discovery Using Guided Model Checking, Neha Shyam Rungta Sep 2006

Improving Error Discovery Using Guided Model Checking, Neha Shyam Rungta

Theses and Dissertations

State exploration in directed software model checking is guided using a heuristic function to move states near errors to the front of the search queue. Distance heuristic functions rank states based on the number of transitions needed to move the current program state into an error location. Lack of calling context information causes the heuristic function to underestimate the true distance to the error; however, inlining functions at call sites in the control flow graph to capture calling context leads to exponential growth in the computation. This paper presents a new algorithm that implicitly inlines functions at call sites to …


Vision-Based Rendering: Using Computational Stereo To Actualize Ibr View Synthesis, Kevin L. Steele Aug 2006

Vision-Based Rendering: Using Computational Stereo To Actualize Ibr View Synthesis, Kevin L. Steele

Theses and Dissertations

Computer graphics imagery (CGI) has enabled many useful applications in training, defense, and entertainment. One such application, CGI simulation, is a real-time system that allows users to navigate through and interact with a virtual rendition of an existing environment. Creating such systems is difficult, but particularly burdensome is the task of designing and constructing the internal representation of the simulation content. Authoring this content on a computer usually requires great expertise and many man-hours of labor. Computational stereo and image-based rendering offer possibilities to automatically create simulation content without user assistance. However, these technologies have largely been limited to creating …


Vectorization Of Raster Images Using B-Spline Surfaces, Curtis A. Armstrong Jul 2006

Vectorization Of Raster Images Using B-Spline Surfaces, Curtis A. Armstrong

Theses and Dissertations

A system has been developed for converting raster images into vector images. Raster images are made of pixels, while vector images are made of smoother shapes. The image is first segmented, and the segments are layered. The boundary of each segment is approximated with a periodic B-Spline curve. This curve is then used to create a B-Spline surface to approximate the interior of the segment. The algorithm fits each B-Spline to the colors of the image using least-squares approximation. The color and shape of each B-Spline surface are extrapolated into regions behind other segments. The result is a vector image …


Characterizing Dynamic Power And Data Rate Policies For Wirelessusb Networks, Jeffrey L. Barlow Jul 2006

Characterizing Dynamic Power And Data Rate Policies For Wirelessusb Networks, Jeffrey L. Barlow

Theses and Dissertations

Wireless communication is increasingly ubiquitous. However, mobility depends intrinsically on battery life. Power can be conserved at the Media Access Control (MAC) layer by intelligently adjusting transmission power level and data rate encoding. WirelessUSB is a low-power, low-latency wireless technology developed by Cypress Semiconductor Corporation for human interface devices such as keyboards and mice. WirelessUSB devices conserve power by employing power-efficient hardware, dynamic power level adjustment and dynamic data rate adjustment. We characterize the effects on power consumption of dynamically adjusting node power using two dynamic power negotiation techniques as well as two reactive techniques. We also characterize the effects …


Local Url Resolution Protocol, Joseph Clark Ekstrom Jul 2006

Local Url Resolution Protocol, Joseph Clark Ekstrom

Theses and Dissertations

DOGMA is a resource management system designed to create a supercomputer like system from unused desktop computers. Scalability is one of the challenges faced by DOGMA because it uses a strict client/server architecture. Distributing large files over a client server architecture is problematic since available network bandwidth is limited. The Local URL Resolution Protocol(LURP) addresses this problem for environments where there are high node densities. LURP implements a locality aware Peer-to-Peer file distribution model to increase the speed of file distribution while reducing the overall network congestion.


A Microformatted Registry Alternative, Thomas R. Warne Jul 2006

A Microformatted Registry Alternative, Thomas R. Warne

Theses and Dissertations

To effectively use Web services, providers and consumers need to be connected by a registry. Several registry solutions exist today, including UDDI and WSIL. Also, many organizations simply use Web pages to list available Web services and their descriptions. This research describes a microformat for representing Web service description documents. These microformatted documents can be converted back to the original format for use by machines. They can also contain additional information, making them more useful to people. A registry, allowing indexing and searching of microformatted service descriptions, is also described. The benefits of this solution include: using existing standards; allowing …


Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham Jul 2006

Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham

Theses and Dissertations

Phylogenetic analysis is a central tool in studies of comparative genomics. When a new region of DNA is isolated and sequenced, researchers are often forced to throw away months of computation on an existing phylogeny of homologous sequences in order to incorporate this new sequence. The previously constructed trees are often discarded, and the researcher begins the search again from scratch. The jumpstarting algorithm uses trees from the prior search as a starting point for a new phylogenetic search. This technique drastically decreases search time for large data sets. This kind of analysis is necessary as researchers analyze tree of …


Improving Record Linkage Through Pedigrees, Burdette N. Pixton Jul 2006

Improving Record Linkage Through Pedigrees, Burdette N. Pixton

Theses and Dissertations

Record linkage, in a genealogical context, is the process of identifying individuals from multiple sources which refer to the same real-world entity. Current solutions focus on the individuals in question and on complex rules developed by human experts. Genealogical databases are highly-structured with relationships existing between the individuals and other instances. These relationships can be utilized and human involvement greatly minimized by using a filtered structured neural network. These neural networks, using traditional back-propagation methods, are biased in a way to make the network human readable. The results show an increase in precision and recall when pedigree data is available …


Markov Approximations: The Characterization Of Undermodeling Errors, Lei Lei Jul 2006

Markov Approximations: The Characterization Of Undermodeling Errors, Lei Lei

Theses and Dissertations

This thesis is concerned with characterizing the quality of Hidden Markov modeling when learning from limited data. It introduces a new perspective on different sources of errors to describe the impact of undermodeling. Our view is that modeling errors can be decomposed into two primary sources of errors: the approximation error and the estimation error. This thesis takes a first step towards exploring the approximation error of low order HMMs that best approximate the true system of a HMM. We introduce the notion minimality and show that best approximations of the true system with complexity greater or equal to the …


Reinforcement Programming: A New Technique In Automatic Algorithm Development, Spencer Kesson White Jul 2006

Reinforcement Programming: A New Technique In Automatic Algorithm Development, Spencer Kesson White

Theses and Dissertations

Reinforcement programming is a new technique for using computers to automatically create algorithms. By using the principles of reinforcement learning and Q-learning, reinforcement programming learns programs based on example inputs and outputs. State representations and actions are provided. A transition function and rewards are defined. The system is trained until the system converges on a policy that can be directly implemented as a computer program. The efficiency of reinforcement programming is demonstrated by comparing a generalized in-place iterative sort learned through genetic programming to a sorting algorithm of the same type created using reinforcement programming. The sort learned by reinforcement …


Brand X, A Cross-Layer Architecture For Quality Of Transport (Qot), Gregory Arthur De Hart Jun 2006

Brand X, A Cross-Layer Architecture For Quality Of Transport (Qot), Gregory Arthur De Hart

Theses and Dissertations

Computing devices are commonly equipped with multiple transport technologies such as IrDA, Bluetooth and WiFi. Transport switching technologies, such as Quality of Transport (QoT), take advantage of this heterogeneity to keep network sessions active as users move in and out of range of various transports or as the networking environment changes. Autonomous transport switching technologies rely on information regarding current network status and the ambient wireless environment in order to make intelligent decisions. This thesis proposes Brand X, a cross-layer architecture designed for a QoT environment to provide timely and accurate environment information in order to facilitate autonomous transport switching. …


A Dynamic Attribute-Based Load Shedding And Data Recovery Scheme For Data Stream Management Systems, Amit Ahuja Jun 2006

A Dynamic Attribute-Based Load Shedding And Data Recovery Scheme For Data Stream Management Systems, Amit Ahuja

Theses and Dissertations

Data streams being transmitted over a network channel with capacity less than the data rate of the data streams is very common when using network channels such as dial-up, low bandwidth wireless links. Not only does this lower capacity creates delays but also causes sequential network problems such as packet losses, network congestion, errors in data packets giving rise to other problems and creating a cycle of problems hard to break out from. In this thesis, we present a new approach for shedding the less informative attribute data from a data stream with a fixed schema to maintain a data …


Guided Interactive Machine Learning, Aaron J. Pace Jun 2006

Guided Interactive Machine Learning, Aaron J. Pace

Theses and Dissertations

This thesis describes a combination of two current areas of research: the Crayons image classifier system and active learning. Currently Crayons provides no guidance to the user in what pixels should be labeled or when the task is complete. This work focuses on two main areas: 1) active learning for user guidance, and 2) accuracy estimation as a measure of completion. First, I provide a study through simulation and user experiments of seven active learning techniques as they relate to Crayons. Three of these techniques were specifically designed for use in Crayons. These three perform comparably to the others and …


Ontology-Based Free-Form Query Processing For The Semantic Web, Mark S. Vickers Jun 2006

Ontology-Based Free-Form Query Processing For The Semantic Web, Mark S. Vickers

Theses and Dissertations

With the onset of the semantic web, the problem of making semantic content effectively searchable for the general public emerges. Demanding an understanding of ontologies or familiarity with a new query language would likely frustrate semantic web users and prevent widespread success. Given this need, this thesis describes AskOntos, which is a system that uses extraction ontologies to convert conjunctive, free-form queries into structured queries for semantically annotated web pages. AskOntos then executes these structured queries and provides answers as tables of extracted values. In experiments conducted AskOntos was able to translate queries with a precision of 88% and a …


Image Vectorization, Brian L. Price May 2006

Image Vectorization, Brian L. Price

Theses and Dissertations

We present a new technique for creating an editable vector graphic from an object in a raster image. Object selection is performed interactively in subsecond time by calling graph cut with each mouse movement. A renderable mesh is then computed automatically for the selected object and each of its (sub)objects by (1) generating a coarse object mesh; (2) performing recursive graph cut segmentation and hierarchical ordering of subobjects; (3) applying error-driven mesh refinement to each (sub)object. The result is a fully layered object hierarchy that facilitates object-level editing without leaving holes. Object-based vectorization compares favorably with current approaches in the …


Temporal Data Mining In A Dynamic Feature Space, Brent K. Wenerstrom May 2006

Temporal Data Mining In A Dynamic Feature Space, Brent K. Wenerstrom

Theses and Dissertations

Many interesting real-world applications for temporal data mining are hindered by concept drift. One particular form of concept drift is characterized by changes to the underlying feature space. Seemingly little has been done to address this issue. This thesis presents FAE, an incremental ensemble approach to mining data subject to concept drift. FAE achieves better accuracies over four large datasets when compared with a similar incremental learning algorithm.


Trust Negotiation For Open Database Access Control, Paul A. Porter May 2006

Trust Negotiation For Open Database Access Control, Paul A. Porter

Theses and Dissertations

Hippocratic databases are designed to protect the privacy of the individuals whose personal information they contain. This thesis presents a model for providing and enforcing access control in an open Hippocratic database system. Previously unknown individuals can gain access to information in the database by authenticating to roles through trust negotiation. Allowing qualified strangers to access the database increases the usefulness of the system without compromising privacy. This thesis presents the design and implementation of two methods for filtering information from database queries. First, we extend a query modification method for use in an open database system. Second, we introduce …


No Free Lunch, Bayesian Inference, And Utility: A Decision-Theoretic Approach To Optimization, Christopher Kenneth Monson Apr 2006

No Free Lunch, Bayesian Inference, And Utility: A Decision-Theoretic Approach To Optimization, Christopher Kenneth Monson

Theses and Dissertations

Existing approaches to continuous optimization are essentially mechanisms for deciding which locations should be sampled in order to obtain information about a target function's global optimum. These methods, while often effective in particular domains, generally base their decisions on heuristics developed in consideration of ill-defined desiderata rather than on explicitly defined goals or models of the available information that may be used to achieve them. The problem of numerical optimization is essentially one of deciding what information to gather, then using that information to infer the location of the global optimum. That being the case, it makes sense to model …


Clustering Of Database Query Results, Kristine Jean Daniels Apr 2006

Clustering Of Database Query Results, Kristine Jean Daniels

Theses and Dissertations

Increasingly more users are accessing database systems for interactive and exploratory data retrieval. While performing searches on these systems, users are required to use broad queries to get their desired results. Broad queries often result in too many items forcing the user to spend unnecessary time sifting through these items to find the relevant results. This problem, of finding a desired data item within many items, is referred to as "information overload". Most users experience information overload when viewing these database query results. This thesis shows that users information overload can be reduced by clustering database query results. …


A Selective Approach To Bandwidth Overbooking, Feng Huang Mar 2006

A Selective Approach To Bandwidth Overbooking, Feng Huang

Theses and Dissertations

Overbooking is a technique used by network providers to increase bandwidth utilization. If the overbooking factor is chosen appropriately, additional virtual circuits can be admitted without degrading quality of service for existing customers. Most existing implementations use a single factor to accept a linear fraction of traffic requests. High values of this factor may cause the degradation of quality of service whereas low overbooking factors will result in underutilization of bandwidth. Network providers often select overbooking factors based only on aggregate average virtual circuit utilization. This paper proposes a selective overbooking scheme based on trunk size and usage profile. Experiments …


User Datagram Protocol With Congestion Control, Spencer L. Cox Mar 2006

User Datagram Protocol With Congestion Control, Spencer L. Cox

Theses and Dissertations

Communication through the Internet is one of the dominant methods of exchanging information. Whether at an individual or large corporate level the Internet has become essential to gathering and disseminating information. TCP and UDP are the transport layer protocols responsible for transit of nearly all Internet communications. Due to the growth of real-time audio and video applications, UDP is being used more frequently as a transport protocol. As UDP traffic increases potential problems arise. Unlike TCP, UDP has no mechanism for congestion control leading to wasted bandwidth and poor performance for other competing protocols. This thesis defines a congestion control …


Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake Mar 2006

Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake

Theses and Dissertations

Learning algorithms based on the Fourier transform attempt to learn functions by approximating the largest coefficients of their Fourier representations. Nearly all previous work in Fourier-based learning has been in the theoretical realm, where properties of the transform have made it possible to prove many interesting learnability results. The real-world usefulness of Fourier-based methods, however, has not been thoroughly explored. This thesis explores methods for the practical application of Fourier-based learning. The primary contribution of this thesis is a new search algorithm for finding the largest coefficients of a function's Fourier representation. Although the search space is exponentially large, empirical …