Physical Sciences and Mathematics Commons^™

Vision-Based Human Directed Robot Guidance, Richard B. Arthur

Theses and Dissertations

This paper describes methods to track a user-defined point in the vision of a robot as it drives forward. This tracking allows a robot to keep itself directed at that point while driving so that it can get to that user-defined point. I develop and present two new multi-scale algorithms for tracking arbitrary points between two frames of video, as well as through a video sequence. The multi-scale algorithms do not use the traditional pyramid image, but instead use a data structure called an integral image (also known as a summed area table). The first algorithm uses edge-detection to track …

Analysis And Comparison Of Three Acoustic Energy Density Probes, Lance Lester Locey

Theses and Dissertations

Traditional methods for the investigation of sound fields generally rely on a microphone to convert sound pressure into an electrical signal which can be recorded, displayed, and so forth. The squared sound pressure is directly related to potential energy density. Consequently, the measurement of sound pressure alone does not inherently provide insight into the total energy density of the sound field. Specifically, no information about the kinetic energy density of the sound field is available from this measurement alone. However, it is possible to use two microphones to estimate particle velocity. The squared particle velocity magnitude is directly related to …

Network-Layer Selective Security, Casey T. Deccio

Theses and Dissertations

The Internet and other large computer networks have become an integral part of numerous daily processes. Security at the network layer is necessary to maintain infrastructure survivability in the case of cyber attacks aimed at routing protocols. In order to minimize undesired overhead associated with added security at this level, the notion of selective security is proposed. This thesis identifies elements in network topologies that are most important to the survivability of the network. The results show that the strategic placement of network security at critical elements will improve overall network survivability without the necessity of universal deployment.

Rapid And Convenient Method For Preparing Masters For Microcontact Printing With 1–12 Μm Features, Lloyd W. Zilch, Ghaleb A. Husseini, Yit-Yian Lua, Michael V. Lee, Kevin R. Gertsch, Bennion R. Cannon, Robert M. Perry, Eric T. Sevy, Matthew C. Asplund, Adam T. Woolley, Matthew R. Linford

Faculty Publications

Mechanical scribing can be employed to create surfaces with recessed features. Through replica molding elastomeric copies of these scribed surfaces are created that function as stamps for microcontact printing. It is shown that this new method for creating masters for microcontact printing can be performed with a computer-controlled milling machine (CNC), making this method particularly straightforward and accessible to a large technical community that does not need to work in a particle free environment. Thus, no clean room, or other specialized equipment is required, as is commonly needed to prepare masters. Time-of-flight secondary ion mass spectrometry confirms surface pattering by …

Evidence Of Linear Lattice Expansion And Covalency Enhancement In Rutile Tio2 Nanocrystals, Guangshe Li, Juliana Boerio-Goates, Brian F. Woodfield, Liping Li

Faculty Publications

Lattice variations and bonding characteristics in rutile TiO2 nanocrystals were examined by x-ray diffraction and x-ray photoelectron spectroscopy. With a reduction in the physical dimensions, rutile TiO2 nanocrystals show a linear lattice expansion and an anomalous covalency enhancement in apparent contradiction to the ionicity increase in BaTiO3 and CuO nanocrystals as reported recently by S. Tsunekawa et al. [Phys. Rev. Lett. 2000, 85, 3440] and V. R. Palkar et al. [Phys. Rev. B 1996, 53, 2167]. A surface defect dipole model is proposed to explain these physical phenomena in terms of the strong interactions among the surface dipoles that produce …

Jumpstarting Phylogenetic Analysis, Mark J. Clement, Keith A. Crandall, Kevin Seppi, Quinn O. Snell

Faculty Publications

When a new epidemic strikes, it is often important to determine the relationship between the current organism and others that have been successfully treated previously. The phylogenetic analysis problem generates the most likely family tree for a group of organisms based on DNA sequence data. This process can take a prohibitively long period of time with current algorithms. If trees resulting from prior searches are used to seed the search, correct trees can be found much more quickly. This jumpstarting algorithm can generate superior phylogenetic solutions much more quickly than existing algorithms.

An Ecological Display For Robot Teleoperation, Robert W. Ricks

Theses and Dissertations

This thesis presents an interface for effectively teleoperating robots that combines an ecological display of range and video information with quickening based on dead-reckoning prediction. This display is built by viewing range and video information from a virtual camera trailing the robot. This is rendered in 3-D by using standard hardware acceleration and 3-D graphics software. Our studies demonstrate that this interface improves performance for most people, including those that do not have much previous experience with robotics. These studies involved 32 test subjects in a simulated environment and 8 in the real world. Subjects were required to drive the …

A Qualitative Method For Dynamic Transport Selection In Heterogeneous Wireless Environments, Heidi R. Duffin

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. During an active session, the goal is to keep the device connected over the best transport currently available. To accomplish that, this thesis introduces a two-phase decision making protocol. In phase one, intra-device prioritization, users indicate the relative importance of criteria such as speed, power, service charge, or signal …

An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston

Faculty Publications

An unusually large specimen of the rare digitate to bladed Aulocopella winnipegensis Rauff and three relatively normal sized specimens of ashtray-shaped Hudsonospongia? sp. constitute the first record of demosponges from the Upper Ordovician Beaverfoot Formation in southeastern British Columbia and the first record of these taxa from western Canada. Gross form and canal structure are well preserved, but dolomitization and (or) coarse microsphaeroidal silicification have obliterated spicules and other structural details. We interpret these sponges as epifaunal recliners, without means of attachment to the substrate, a life mode rarely encountered in the modern sponge biota.

T-Spline Simplification And Local Refinement, David L. Cardon, G. Thomas Finnigan, Nicholas S. North, Thomas W. Sederberg, Jianmin Zheng, Tom Lyche

Faculty Publications

A typical NURBS surface model has a large percentage of superfluous control points that significantly interfere with the design process. This paper presents an algorithm for eliminating such superfluous control points, producing a T-spline. The algorithm can remove substantially more control points than competing methods such as B-spline wavelet decomposition. The paper also presents a new T-spline local refinement algorithm and answers two fundamental open questions on T-spline theory.

Instructing Teachers Of Children With Disabilities Within The Church Of Jesus Christ Of Latter-Day Saints, Katie E. Sampson

Theses and Dissertations

This study investigates benefits of in-service training on LDS primary teachers' ability to state an objective, obtain and keep attention, use wait time, incorporate active participation, teach to the multiple intelligences, and employ positive behavior management techniques. Two groups of 30 viewed either a video-tape or read a handout. Pre and post surveys were used to determine mean gain.
Using an ANCOVA, comparisons were made of overall mean gain for each group. Results showed participants made a gain of approximately 1/2 point per question on a 4-point scale on the video and the handout (video gain = .6032 p<.01; handout gain = .6264 p<.01). The results of this study support the hypothesis that teachers receiving one in-service will increase their perception of their ability to teach students with special needs.

Capillary Liquid Chromatography Using Micro Size Particles, Yanqiao Xiang

Theses and Dissertations

High speed and/or high efficiency separations can be realized using small particles (~ 1 µm) in liquid chromatography (LC). However, due to the large pressure drop caused by small particles, conventional LC pumping systems cannot satisfy the pressure requirements needed to drive the mobile phase through the column. Use of ultrahigh pressure, elevated temperature, or both can overcome these pressure limitations and allow the use of very small particles for high speed and/or high efficiency separations.

In this dissertation, the use of ultrahigh pressures with and without elevated temperatures in capillary LC is described. Very fast separations of various samples …

Feature Weighting Using Neural Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

In this work we propose a feature weighting method for classification tasks by extracting relevant information from a trained neural network. This method weights an attribute based on strengths (weights) of related links in the neural network, in which an important feature is typically connected to strong links and has more impact on the outputs. This method is applied to feature weighting br the nearest neighbor classifier and is tested on 15 real-world classification tasks. The results show that it can improve the nearest neighbor classifier on 14 of the 15 tested tasks, and also outperforms the neural network on …

Using Permutations Instead Of Student’S T Distribution For P-Values In Paired-Difference Algorithm Comparisons, Tony R. Martinez, Joshua Menke

Faculty Publications

The paired-difference t-test is commonly used in the machine learning community to determine whether one learning algorithm is better than another on a given learning task. This paper suggests the use of the permutation test instead hecause it calculates the exact p-value instead of an estimate. The permutation test is also distribution free and the time complexity is trivial for the commonly used 10-fold cross-validation paired-difference test. Results of experiments on real-world problems suggest it is not uncommon to see the t-test estimate deviate up to 30-50% from the exact p-value.

Softprop: Softmax Neural Network Backpropagation Learning, Tony R. Martinez, Michael E. Rimer

Faculty Publications

Multi-layer backpropagation, like many learning algorithms that can create complex decision surfaces, is prone to overfitting. Softprop is a novel learning approach presented here that is reminiscent of the softmax explore-exploit Q-learning search heuristic It fits the problem while delaying settling into error minima to achieve better generalization and more robust learning. This is accomplished by blending standard SSE optimization with lazy training, a new objective function well suited to learning classification tasks, to form a more stable learning model. Over several machine learning data sets, softprop reduces classification error by 17.1 percent and the variance in results by 38.6 …

Probabilistic Methodology For Record Linkage Determining Robustness Of Weights, Krista Peine Jensen

Theses and Dissertations

Record linkage is the process that joins separately recorded pieces of information for a particular individual from one or more sources. To facilitate record linkage, a reliable computer based approach is ideal. In genealogical research computerized record linkage is useful in combing information for an individual across multiple censuses.

In creating a computerized method for linking censuse records it needs to be determined if weights calculated from one geographical area, can be used to link records from another geographical area. Research performed by Marcie Francis calculates field weights using census records from 1910 and 1920 for Ascension Parish Louisiana. These …

On The Variability Of The Fine Structure Constant, Jason Lott Evans

Theses and Dissertations

This thesis addresses the issue of the time variability of the fine structure constant, alpha. Recent claims of a varying alpha are set against the established standards of quantum electrodynamical theory and experiments. A study of the feasibility of extracting data on the time dependence of alpha using particles in Penning traps is compared to the results obtained by existing methods, including those using astrophysical data and those obtained in atomic clock experiments. Suggestions are made on the nature of trapped particles and the trapping fields.

Preserving Trust Across Multiple Sessions In Open Systems, Fuk-Wing Thomas Chan

Theses and Dissertations

Trust negotiation, a new authentication paradigm, enables strangers on the Internet to establish trust through the gradual disclosure of digital credentials and access control policies. Previous research in trust negotiation does not address issues in preserving trust across multiple sessions. This thesis discusses issues in preserving trust between parties who were previously considered strangers. It also describes the design and implementation of trust preservation in TrustBuilder, a prototype trust negotiation system. Preserving trust information can reduce the frequency and cost of renegotiation. A scenario is presented that demonstrates that a server supporting trust preservation can recoup the cost of the …

Hiring Practices For Graphic Designers In Utah County, Utah, Landon T. Densley

Theses and Dissertations

The purpose of this study was to show how hiring standards of evidence for graphic designers in Utah County compared with the national standards of evidence. The four major national standards of evidence for hiring graphic designers, identified by American Institute of Graphic Arts (AIGA) and Goldfarb, in order of importance are portfolio, recommendations, personality, and education. The data from this study revealed that Utah County employer's standards of evidence matched up closely to national standards of evidence, but the order of importance was slightly different because personality was ranked ahead of recommendations and education.

A Numerical Scheme For Mullins-Sekerka Flow In Three Space Dimensions, Sarah Marie Brown

Theses and Dissertations

The Mullins-Sekerka problem, also called two-sided Hele-Shaw flow, arises in modeling a binary material with two stable concentration phases. A coarsening process occurs, and large particles grow while smaller particles eventually dissolve. Single particles become spherical. This process is described by evolving harmonic functions within the two phases with the moving interface driven by the jump in the normal derivatives of the harmonic functions at the interface. The harmonic functions are continuous across the interface, taking on values equal to the mean curvature of the interface. This dissertation reformulates the three-dimensional problem as one on the two-dimensional interface by using …

Grouping Search-Engine Returned Citations For Person-Name Queries, Reema Al-Kamha

Theses and Dissertations

In this thesis we present a technique to group search-engine returned citations for person-name queries, such that the search-engine returned citations in each group belong to the same person. To group the returned citations we use a multi-faceted approach that considers evidence from three facets: (1) attributes, (2) links, and (3) page similarity. For each facet we generate a confidence matrix. Then we construct a final confidence matrix for all facets. Using a threshold, we apply a grouping algorithm on the final confidence matrix. The output is a group of search-engine returned citations, such that the citations in each group …

Psl(2,7)-Extensions With Certain Ramification At Two Primes, Glen E. Simpson

Theses and Dissertations

We conduct a parallel Hunter search in order to find a degree 7 number field K ramified at primes q and p with discriminant d(K)=q^6 p^2 where q=11 and 2

Choosing A Starting Configuration For Particle Swarm Optimization, Mark Richards, Dan A. Ventura

Faculty Publications

The performance of Particle Swarm Optimization can be improved by strategically selecting the starting positions of the particles. This work suggests the use of generators from centroidal Voronoi tessellations as the starting points for the swarm. The performance of swarms initialized with this method is compared with the standard PSO algorithm on several standard test functions. Results suggest that CVT initialization improves PSO performance in high-dimensional spaces.

Incremental Policy Learning: An Equilibrium Selection Algorithm For Reinforcement Learning Agents With Common Interests, Nancy Fulda, Dan A. Ventura

Faculty Publications

We present an equilibrium selection algorithm for reinforcement learning agents that incrementally adjusts the probability of executing each action based on the desirability of the outcome obtained in the last time step. The algorithm assumes that at least one coordination equilibrium exists and requires that the agents have a heuristic for determining whether or not the equilibrium was obtained. In deterministic environments with one or more strict coordination equilibria, the algorithm will learn to play an optimal equilibrium as long as the heuristic is accurate. Empirical data demonstrate that the algorithm is also effective in stochastic environments and is able …

Learning Multiple Correct Classifications From Incomplete Data Using Weakened Implicit Negatives, Dan A. Ventura, Stephen Whiting

Faculty Publications

Classification problems with output class overlap create problems for standard neural network approaches. We present a modification of a simple feed-forward neural network that is capable of learning problems with output overlap, including problems exhibiting hierarchical class structures in the output. Our method of applying weakened implicit negatives to address overlap and ambiguity allows the algorithm to learn a large portion of the hierarchical structure from very incomplete data. Our results show an improvement of approximately 58% over a standard backpropagation network on the hierarchical problem.

Task-Focused Summarization Of Email, Eric K. Ringger, Richard Campbell, Simon Corston-Oliver, Michael Gamon

Faculty Publications

We describe SmartMail, a prototype system for automatically identifying action items (tasks) in email messages. SmartMail presents the user with a task-focused summary of a message. The summary consists of a list of action items extracted from the message. The user can add these action items to their “to do” list.

Load Balancing Parallel Explicit State Model Checking, Rahul Kumar

Theses and Dissertations

This research first identifies some of the key concerns about the techniques and algorithms developed for distributed and parallel model checking; specifically, the inherent problem with load balancing and large queue sizes resultant in a static partition algorithm. This research then presents a load balancing algorithm to improve the run time performance in distributed model checking, reduce maximum queue size, and reduce the number of states expanded before error discovery. The load balancing algorithm is based on Generalized Dimension Exchange (GDE). This research presents an empirical analysis of the GDE based load balancing algorithm on three different supercomputing architectures---distributed memory …

Platinum Group Element Mineralization In "Ballrooms" Of The J-M Reef Of The Stillwater Complex, Montana, Matthew P. Harper

Theses and Dissertations

The J-M Reef of the Stillwater Complex, Montana (a large layered mafic intrusion), is one of the highest grade platinum group element (PGE) deposits known in the world, producing primarily palladium and platinum in a 3.4:1 ratio. "Ballrooms" of the Stillwater Complex are anomalously wide areas within or stratigraphically below the J-M Reef that host platinum group element mineralization. Ballrooms have two typical morphologies (type 1 and type 2); the first is an abrupt thickening of the mineralization that extends below the Reef Package and the second is a gentle widening of the Reef Package and associated reef mineralization to …

A New Approach To Lie Symmetry Groups Of Minimal Surfaces, Robert D. Berry

Theses and Dissertations

The Lie symmetry groups of minimal surfaces by way of planar harmonic functions are determined. It is shown that a symmetry group acting on the minimal surfaces is isomorphic with H × H^2 — the analytic functions and the harmonic functions. A subgroup of this gives a generalization of the associated family which is examined.

Solving Large Mdps Quickly With Partitioned Value Iteration, David Wingate

Theses and Dissertations

Value iteration is not typically considered a viable algorithm for solving large-scale MDPs because it converges too slowly. However, its performance can be dramatically improved by eliminating redundant or useless backups, and by backing up states in the right order. We present several methods designed to help structure value dependency, and present a systematic study of companion prioritization techniques which focus computation in useful regions of the state space. In order to scale to solve ever larger problems, we evaluate all enhancements and methods in the context of parallelizability. Using the enhancements, we discover that in many instances the limiting …